Merge pull request #3681 from karalabe/usb-hidapi

accounts/usbwallet: swap karalabe/gousb to karalabe/hid

83 files changed, 5659 insertions, 1838 deletions

diff --git a/accounts/usbwallet/ledger_hub.go b/accounts/usbwallet/ledger_hub.go
index ad5940cd4..70396d314 100644
--- a/accounts/usbwallet/ledger_hub.go
+++ b/accounts/usbwallet/ledger_hub.go
@@ -18,18 +18,16 @@
 // wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
 // https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
 
-// +build !ios
-
 package usbwallet
 
 import (
-	"fmt"
+	"errors"
 	"sync"
 	"time"
 
 	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/event"
-	"github.com/karalabe/gousb/usb"
+	"github.com/karalabe/hid"
 )
 
 // LedgerScheme is the protocol scheme prefixing account and wallet URLs.
@@ -49,8 +47,6 @@ const ledgerRefreshThrottling = 500 * time.Millisecond
 
 // LedgerHub is a accounts.Backend that can find and handle Ledger hardware wallets.
 type LedgerHub struct {
-	ctx *usb.Context // Context interfacing with a libusb instance
-
 	refreshed   time.Time               // Time instance when the list of wallets was last refreshed
 	wallets     []accounts.Wallet       // List of Ledger devices currently tracking
 	updateFeed  event.Feed              // Event feed to notify wallet additions/removals
@@ -63,18 +59,13 @@ type LedgerHub struct {
 
 // NewLedgerHub creates a new hardware wallet manager for Ledger devices.
 func NewLedgerHub() (*LedgerHub, error) {
-	// Initialize the USB library to access Ledgers through
-	ctx, err := usb.NewContext()
-	if err != nil {
-		return nil, err
+	if !hid.Supported() {
+		return nil, errors.New("unsupported platform")
 	}
-	// Create the USB hub, start and return it
 	hub := &LedgerHub{
-		ctx:  ctx,
 		quit: make(chan chan error),
 	}
 	hub.refreshWallets()
-
 	return hub, nil
 }
 
@@ -104,31 +95,23 @@ func (hub *LedgerHub) refreshWallets() {
 		return
 	}
 	// Retrieve the current list of Ledger devices
-	var devIDs []deviceID
-	var busIDs []uint16
-
-	hub.ctx.ListDevices(func(desc *usb.Descriptor) bool {
-		// Gather Ledger devices, don't connect any just yet
+	var ledgers []hid.DeviceInfo
+	for _, info := range hid.Enumerate(0, 0) { // Can't enumerate directly, one valid ID is the 0 wildcard
 		for _, id := range ledgerDeviceIDs {
-			if desc.Vendor == id.Vendor && desc.Product == id.Product {
-				devIDs = append(devIDs, deviceID{Vendor: desc.Vendor, Product: desc.Product})
-				busIDs = append(busIDs, uint16(desc.Bus)<<8+uint16(desc.Address))
-				return false
+			if info.VendorID == id.Vendor && info.ProductID == id.Product {
+				ledgers = append(ledgers, info)
+				break
 			}
 		}
-		// Not ledger, ignore and don't connect either
-		return false
-	})
+	}
 	// Transform the current list of wallets into the new one
 	hub.lock.Lock()
 
-	wallets := make([]accounts.Wallet, 0, len(devIDs))
+	wallets := make([]accounts.Wallet, 0, len(ledgers))
 	events := []accounts.WalletEvent{}
 
-	for i := 0; i < len(devIDs); i++ {
-		devID, busID := devIDs[i], busIDs[i]
-
-		url := accounts.URL{Scheme: LedgerScheme, Path: fmt.Sprintf("%03d:%03d", busID>>8, busID&0xff)}
+	for _, ledger := range ledgers {
+		url := accounts.URL{Scheme: LedgerScheme, Path: ledger.Path}
 
 		// Drop wallets in front of the next device or those that failed for some reason
 		for len(hub.wallets) > 0 && (hub.wallets[0].URL().Cmp(url) < 0 || hub.wallets[0].(*ledgerWallet).failed()) {
@@ -137,7 +120,7 @@ func (hub *LedgerHub) refreshWallets() {
 		}
 		// If there are no more wallets or the device is before the next, wrap new wallet
 		if len(hub.wallets) == 0 || hub.wallets[0].URL().Cmp(url) > 0 {
-			wallet := &ledgerWallet{context: hub.ctx, hardwareID: devID, locationID: busID, url: &url}
+			wallet := &ledgerWallet{url: &url, info: ledger}
 
 			events = append(events, accounts.WalletEvent{Wallet: wallet, Arrive: true})
 			wallets = append(wallets, wallet)
diff --git a/accounts/usbwallet/ledger_wallet.go b/accounts/usbwallet/ledger_wallet.go
index a667f580a..235086d1e 100644
--- a/accounts/usbwallet/ledger_wallet.go
+++ b/accounts/usbwallet/ledger_wallet.go
@@ -18,8 +18,6 @@
 // wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
 // https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
 
-// +build !ios
-
 package usbwallet
 
 import (
@@ -39,7 +37,7 @@ import (
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
 	"github.com/ethereum/go-ethereum/rlp"
-	"github.com/karalabe/gousb/usb"
+	"github.com/karalabe/hid"
 	"golang.org/x/net/context"
 )
 
@@ -74,22 +72,22 @@ const (
 	ledgerP2ReturnAddressChainCode  ledgerParam2 = 0x01 // Require a user confirmation before returning the address
 )
 
-// errReplyInvalidHeader is the error message returned by a Ledfer data exchange
+// errReplyInvalidHeader is the error message returned by a Ledger data exchange
 // if the device replies with a mismatching header. This usually means the device
 // is in browser mode.
 var errReplyInvalidHeader = errors.New("invalid reply header")
 
+// errInvalidVersionReply is the error message returned by a Ledger version retrieval
+// when a response does arrive, but it does not contain the expected data.
+var errInvalidVersionReply = errors.New("invalid version reply")
+
 // ledgerWallet represents a live USB Ledger hardware wallet.
 type ledgerWallet struct {
-	context    *usb.Context  // USB context to interface libusb through
-	hardwareID deviceID      // USB identifiers to identify this device type
-	locationID uint16        // USB bus and address to identify this device instance
-	url        *accounts.URL // Textual URL uniquely identifying this wallet
+	url *accounts.URL // Textual URL uniquely identifying this wallet
 
-	device  *usb.Device  // USB device advertising itself as a Ledger wallet
-	input   usb.Endpoint // Input endpoint to send data to this device
-	output  usb.Endpoint // Output endpoint to receive data from this device
-	failure error        // Any failure that would make the device unusable
+	info    hid.DeviceInfo // Known USB device infos about the wallet
+	device  *hid.Device    // USB device advertising itself as a Ledger wallet
+	failure error          // Any failure that would make the device unusable
 
 	version  [3]byte                                    // Current version of the Ledger Ethereum app (zero if app is offline)
 	browser  bool                                       // Flag whether the Ledger is in browser mode (reply channel mismatch)
@@ -183,59 +181,12 @@ func (w *ledgerWallet) Open(passphrase string) error {
 		return accounts.ErrWalletAlreadyOpen
 	}
 	// Otherwise iterate over all USB devices and find this again (no way to directly do this)
-	// Iterate over all attached devices and fetch those seemingly Ledger
-	devices, err := w.context.ListDevices(func(desc *usb.Descriptor) bool {
-		// Only open this single specific device
-		return desc.Vendor == w.hardwareID.Vendor && desc.Product == w.hardwareID.Product &&
-			uint16(desc.Bus)<<8+uint16(desc.Address) == w.locationID
-	})
+	device, err := w.info.Open()
 	if err != nil {
 		return err
 	}
-	if len(devices) == 0 {
-		return accounts.ErrUnknownWallet
-	}
-	// Device opened, attach to the input and output endpoints
-	device := devices[0]
-
-	var invalid string
-	switch {
-	case len(device.Descriptor.Configs) == 0:
-		invalid = "no endpoint config available"
-	case len(device.Descriptor.Configs[0].Interfaces) == 0:
-		invalid = "no endpoint interface available"
-	case len(device.Descriptor.Configs[0].Interfaces[0].Setups) == 0:
-		invalid = "no endpoint setup available"
-	case len(device.Descriptor.Configs[0].Interfaces[0].Setups[0].Endpoints) < 2:
-		invalid = "not enough IO endpoints available"
-	}
-	if invalid != "" {
-		device.Close()
-		return fmt.Errorf("ledger wallet [%s] invalid: %s", w.url, invalid)
-	}
-	// Open the input and output endpoints to the device
-	input, err := device.OpenEndpoint(
-		device.Descriptor.Configs[0].Config,
-		device.Descriptor.Configs[0].Interfaces[0].Number,
-		device.Descriptor.Configs[0].Interfaces[0].Setups[0].Number,
-		device.Descriptor.Configs[0].Interfaces[0].Setups[0].Endpoints[1].Address,
-	)
-	if err != nil {
-		device.Close()
-		return fmt.Errorf("ledger wallet [%s] input open failed: %v", w.url, err)
-	}
-	output, err := device.OpenEndpoint(
-		device.Descriptor.Configs[0].Config,
-		device.Descriptor.Configs[0].Interfaces[0].Number,
-		device.Descriptor.Configs[0].Interfaces[0].Setups[0].Number,
-		device.Descriptor.Configs[0].Interfaces[0].Setups[0].Endpoints[0].Address,
-	)
-	if err != nil {
-		device.Close()
-		return fmt.Errorf("ledger wallet [%s] output open failed: %v", w.url, err)
-	}
 	// Wallet seems to be successfully opened, guess if the Ethereum app is running
-	w.device, w.input, w.output = device, input, output
+	w.device = device
 	w.commsLock = make(chan struct{}, 1)
 	w.commsLock <- struct{}{} // Enable lock
 
@@ -298,13 +249,13 @@ func (w *ledgerWallet) heartbeat() {
 		w.commsLock <- struct{}{}
 		w.stateLock.RUnlock()
 
-		if err == usb.ERROR_IO || err == usb.ERROR_NO_DEVICE {
+		if err != nil && err != errInvalidVersionReply {
 			w.stateLock.Lock() // Lock state to tear the wallet down
 			w.failure = err
 			w.close()
 			w.stateLock.Unlock()
 		}
-		// Ignore uninteresting errors
+		// Ignore non hardware related errors
 		err = nil
 	}
 	// In case of error, wait for termination
@@ -363,13 +314,13 @@ func (w *ledgerWallet) close() error {
 		return nil
 	}
 	// Close the device, clear everything, then return
-	err := w.device.Close()
+	w.device.Close()
+	w.device = nil
 
-	w.device, w.input, w.output = nil, nil, nil
 	w.browser, w.version = false, [3]byte{}
 	w.accounts, w.paths = nil, nil
 
-	return err
+	return nil
 }
 
 // Accounts implements accounts.Wallet, returning the list of accounts pinned to
@@ -664,7 +615,7 @@ func (w *ledgerWallet) ledgerVersion() ([3]byte, error) {
 		return [3]byte{}, err
 	}
 	if len(reply) != 4 {
-		return [3]byte{}, errors.New("reply not of correct size")
+		return [3]byte{}, errInvalidVersionReply
 	}
 	// Cache the version for future reference
 	var version [3]byte
@@ -768,10 +719,6 @@ func (w *ledgerWallet) ledgerDerive(derivationPath []uint32) (common.Address, er
 //   signature R | 32 bytes
 //   signature S | 32 bytes
 func (w *ledgerWallet) ledgerSign(derivationPath []uint32, address common.Address, tx *types.Transaction, chainID *big.Int) (*types.Transaction, error) {
-	// We need to modify the timeouts to account for user feedback
-	defer func(old time.Duration) { w.device.ReadTimeout = old }(w.device.ReadTimeout)
-	w.device.ReadTimeout = time.Hour * 24 * 30 // Timeout requires a Ledger power cycle, only if you must
-
 	// Flatten the derivation path into the Ledger request
 	path := make([]byte, 1+4*len(derivationPath))
 	path[0] = byte(len(derivationPath))
@@ -903,9 +850,9 @@ func (w *ledgerWallet) ledgerExchange(opcode ledgerOpcode, p1 ledgerParam1, p2 l
 		}
 		// Send over to the device
 		if glog.V(logger.Detail) {
-			glog.Infof("-> %03d.%03d: %x", w.device.Bus, w.device.Address, chunk)
+			glog.Infof("-> %s: %x", w.device.Path, chunk)
 		}
-		if _, err := w.input.Write(chunk); err != nil {
+		if _, err := w.device.Write(chunk); err != nil {
 			return nil, err
 		}
 	}
@@ -914,11 +861,11 @@ func (w *ledgerWallet) ledgerExchange(opcode ledgerOpcode, p1 ledgerParam1, p2 l
 	chunk = chunk[:64] // Yeah, we surely have enough space
 	for {
 		// Read the next chunk from the Ledger wallet
-		if _, err := io.ReadFull(w.output, chunk); err != nil {
+		if _, err := io.ReadFull(w.device, chunk); err != nil {
 			return nil, err
 		}
 		if glog.V(logger.Detail) {
-			glog.Infof("<- %03d.%03d: %x", w.device.Bus, w.device.Address, chunk)
+			glog.Infof("<- %s: %x", w.device.Path, chunk)
 		}
 		// Make sure the transport header matches
 		if chunk[0] != 0x01 || chunk[1] != 0x01 || chunk[2] != 0x05 {
diff --git a/accounts/usbwallet/usbwallet.go b/accounts/usbwallet/usbwallet.go
index 3989f3d02..938ab1e6a 100644
--- a/accounts/usbwallet/usbwallet.go
+++ b/accounts/usbwallet/usbwallet.go
@@ -14,16 +14,12 @@
 // You should have received a copy of the GNU Lesser General Public License
 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 
-// +build !ios
-
 // Package usbwallet implements support for USB hardware wallets.
 package usbwallet
 
-import "github.com/karalabe/gousb/usb"
-
 // deviceID is a combined vendor/product identifier to uniquely identify a USB
 // hardware device.
 type deviceID struct {
-	Vendor  usb.ID // The Vendor identifer
-	Product usb.ID // The Product identifier
+	Vendor  uint16 // The Vendor identifer
+	Product uint16 // The Product identifier
 }
diff --git a/accounts/usbwallet/usbwallet_ios.go b/accounts/usbwallet/usbwallet_ios.go
deleted file mode 100644
index 17d342903..000000000
--- a/accounts/usbwallet/usbwallet_ios.go
+++ /dev/null
@@ -1,38 +0,0 @@
-// Copyright 2017 The go-ethereum Authors
-// This file is part of the go-ethereum library.
-//
-// The go-ethereum library is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-//
-// The go-ethereum library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU Lesser General Public License for more details.
-//
-// You should have received a copy of the GNU Lesser General Public License
-// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
-
-// This file contains the implementation for interacting with the Ledger hardware
-// wallets. The wire protocol spec can be found in the Ledger Blue GitHub repo:
-// https://raw.githubusercontent.com/LedgerHQ/blue-app-eth/master/doc/ethapp.asc
-
-// +build ios
-
-package usbwallet
-
-import (
-	"errors"
-
-	"github.com/ethereum/go-ethereum/accounts"
-)
-
-// Here be dragons! There is no USB support on iOS.
-
-// ErrIOSNotSupported is returned for all USB hardware backends on iOS.
-var ErrIOSNotSupported = errors.New("no USB support on iOS")
-
-func NewLedgerHub() (accounts.Backend, error) {
-	return nil, ErrIOSNotSupported
-}
diff --git a/vendor/github.com/karalabe/gousb/.gitignore b/vendor/github.com/karalabe/gousb/.gitignore
deleted file mode 100644
index dbec55fb6..000000000
--- a/vendor/github.com/karalabe/gousb/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-*.sw[op]
diff --git a/vendor/github.com/karalabe/gousb/.travis.yml b/vendor/github.com/karalabe/gousb/.travis.yml
deleted file mode 100644
index 2029cc478..000000000
--- a/vendor/github.com/karalabe/gousb/.travis.yml
+++ /dev/null
@@ -1,12 +0,0 @@
-language: go
-
-matrix:
-  include:
-    - os: linux
-      dist: trusty
-      go: 1.7.4
-    - os: osx
-      go: 1.7.4
-
-script:
-  - go test -v -test.run='BCD|Parse' ./...
diff --git a/vendor/github.com/karalabe/gousb/LICENSE b/vendor/github.com/karalabe/gousb/LICENSE
deleted file mode 100644
index d64569567..000000000
--- a/vendor/github.com/karalabe/gousb/LICENSE
+++ /dev/null
@@ -1,202 +0,0 @@
-
-                                 Apache License
-                           Version 2.0, January 2004
-                        http://www.apache.org/licenses/
-
-   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
-
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-      outstanding shares, or (iii) beneficial ownership of such entity.
-
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-      on Your own behalf and on Your sole responsibility, not on behalf
-      of any other Contributor, and only if You agree to indemnify,
-      defend, and hold each Contributor harmless for any liability
-      incurred by, or claims asserted against, such Contributor by reason
-      of your accepting any such warranty or additional liability.
-
-   END OF TERMS AND CONDITIONS
-
-   APPENDIX: How to apply the Apache License to your work.
-
-      To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "[]"
-      replaced with your own identifying information. (Don't include
-      the brackets!)  The text should be enclosed in the appropriate
-      comment syntax for the file format. We also recommend that a
-      file or class name and description of purpose be included on the
-      same "printed page" as the copyright notice for easier
-      identification within third-party archives.
-
-   Copyright [yyyy] [name of copyright owner]
-
-   Licensed under the Apache License, Version 2.0 (the "License");
-   you may not use this file except in compliance with the License.
-   You may obtain a copy of the License at
-
-       http://www.apache.org/licenses/LICENSE-2.0
-
-   Unless required by applicable law or agreed to in writing, software
-   distributed under the License is distributed on an "AS IS" BASIS,
-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-   See the License for the specific language governing permissions and
-   limitations under the License.
diff --git a/vendor/github.com/karalabe/gousb/README.md b/vendor/github.com/karalabe/gousb/README.md
deleted file mode 100644
index 05f333003..000000000
--- a/vendor/github.com/karalabe/gousb/README.md
+++ /dev/null
@@ -1,47 +0,0 @@
-Introduction
-============
-
-[![Travis Build Status][travisimg]][travis]
-[![AppVeyor Build Status][appveyorimg]][appveyor]
-[![GoDoc][docimg]][doc]
-
-The gousb package is an attempt at wrapping the `libusb` library into a Go-like binding in a fully self-contained, go-gettable package. Supported platforms include Linux, macOS and Windows as well as the mobile platforms Android and iOS.
-
-This package is a fork of [`github.com/kylelemons/gousb`](https://github.com/kylelemons/gousb), which at the moment seems to be unmaintained. The current fork is different from the upstream package as it contains code to embed `libusb` directly into the Go package (thus becoming fully self-cotnained and go-gettable), as well as it features a few contributions and bugfixes that never really got addressed in the upstream package, but which address important issues nonetheless.
-
-*Note, if @kylelemons decides to pick development of the upstream project up again, consider all commits made by me to this repo as ready contributions. I cannot vouch for other commits as the upstream repo needs a signed CLA for Google.*
-
-[travisimg]:   https://travis-ci.org/karalabe/gousb.svg?branch=master
-[travis]:      https://travis-ci.org/karalabe/gousb
-[appveyorimg]: https://ci.appveyor.com/api/projects/status/84k9xse10rl72gn2/branch/master?svg=true
-[appveyor]:    https://ci.appveyor.com/project/karalabe/gousb
-[docimg]:      https://godoc.org/github.com/karalabe/gousb?status.svg
-[doc]:         https://godoc.org/github.com/karalabe/gousb
-
-Installation
-============
-
-Example: lsusb
---------------
-The gousb project provides a simple but useful example: lsusb.  This binary will list the USB devices connected to your system and various interesting tidbits about them, their configurations, endpoints, etc.  To install it, run the following command:
-
-    go get -v github.com/karalabe/gousb/lsusb
-
-gousb
------
-If you installed the lsusb example, both libraries below are already installed.
-
-Installing the primary gousb package is really easy:
-
-    go get -v github.com/karalabe/gousb/usb
-
-There is also a `usbid` package that will not be installed by default by this command, but which provides useful information including the human-readable vendor and product codes for detected hardware.  It's not installed by default and not linked into the `usb` package by default because it adds ~400kb to the resulting binary.  If you want both, they can be installed thus:
-
-    go get -v github.com/karalabe/gousb/usb{,id}
-
-Documentation
-=============
-The documentation can be viewed via local godoc or via the excellent [godoc.org](http://godoc.org/):
-
-- [usb](http://godoc.org/github.com/karalabe/gousb/usb)
-- [usbid](http://godoc.org/pkg/github.com/karalabe/gousb/usbid)
diff --git a/vendor/github.com/karalabe/gousb/appveyor.yml b/vendor/github.com/karalabe/gousb/appveyor.yml
deleted file mode 100644
index b24986202..000000000
--- a/vendor/github.com/karalabe/gousb/appveyor.yml
+++ /dev/null
@@ -1,34 +0,0 @@
-os: Visual Studio 2015
-
-# Clone directly into GOPATH.
-clone_folder: C:\gopath\src\github.com\karalabe\gousb
-clone_depth: 5
-version: "{branch}.{build}"
-environment:
-  global:
-    GOPATH: C:\gopath
-    CC: gcc.exe
-  matrix:
-    - GOARCH: amd64
-      MSYS2_ARCH: x86_64
-      MSYS2_BITS: 64
-      MSYSTEM: MINGW64
-      PATH: C:\msys64\mingw64\bin\;%PATH%
-    - GOARCH: 386
-      MSYS2_ARCH: i686
-      MSYS2_BITS: 32
-      MSYSTEM: MINGW32
-      PATH: C:\msys64\mingw32\bin\;%PATH%
-
-install:
-  - rmdir C:\go /s /q
-  - appveyor DownloadFile https://storage.googleapis.com/golang/go1.7.4.windows-%GOARCH%.zip
-  - 7z x go1.7.4.windows-%GOARCH%.zip -y -oC:\ > NUL
-  - go version
-  - gcc --version
-
-build_script:
-  - go install ./...
-
-test_script:
-  - go test -v -test.run="BCD|Parse" ./...
diff --git a/vendor/github.com/karalabe/gousb/usb/config.go b/vendor/github.com/karalabe/gousb/usb/config.go
deleted file mode 100644
index 840bce63c..000000000
--- a/vendor/github.com/karalabe/gousb/usb/config.go
+++ /dev/null
@@ -1,153 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-/*
-#ifndef OS_WINDOWS
-	#include "os/threads_posix.h"
-#endif
-#include "libusbi.h"
-#include "libusb.h"
-*/
-import "C"
-
-import (
-	"fmt"
-	"reflect"
-	"unsafe"
-)
-
-type EndpointInfo struct {
-	Address       uint8
-	Attributes    uint8
-	MaxPacketSize uint16
-	MaxIsoPacket  uint32
-	PollInterval  uint8
-	RefreshRate   uint8
-	SynchAddress  uint8
-}
-
-func (e EndpointInfo) Number() int {
-	return int(e.Address) & ENDPOINT_NUM_MASK
-}
-
-func (e EndpointInfo) Direction() EndpointDirection {
-	return EndpointDirection(e.Address) & ENDPOINT_DIR_MASK
-}
-
-func (e EndpointInfo) String() string {
-	return fmt.Sprintf("Endpoint %d %-3s %s - %s %s [%d %d]",
-		e.Number(), e.Direction(),
-		TransferType(e.Attributes)&TRANSFER_TYPE_MASK,
-		IsoSyncType(e.Attributes)&ISO_SYNC_TYPE_MASK,
-		IsoUsageType(e.Attributes)&ISO_USAGE_TYPE_MASK,
-		e.MaxPacketSize, e.MaxIsoPacket,
-	)
-}
-
-type InterfaceInfo struct {
-	Number uint8
-	Setups []InterfaceSetup
-}
-
-func (i InterfaceInfo) String() string {
-	return fmt.Sprintf("Interface %02x (%d setups)", i.Number, len(i.Setups))
-}
-
-type InterfaceSetup struct {
-	Number     uint8
-	Alternate  uint8
-	IfClass    uint8
-	IfSubClass uint8
-	IfProtocol uint8
-	Endpoints  []EndpointInfo
-}
-
-func (a InterfaceSetup) String() string {
-	return fmt.Sprintf("Interface %02x Setup %02x", a.Number, a.Alternate)
-}
-
-type ConfigInfo struct {
-	Config     uint8
-	Attributes uint8
-	MaxPower   uint8
-	Interfaces []InterfaceInfo
-}
-
-func (c ConfigInfo) String() string {
-	return fmt.Sprintf("Config %02x", c.Config)
-}
-
-func newConfig(dev *C.libusb_device, cfg *C.struct_libusb_config_descriptor) ConfigInfo {
-	c := ConfigInfo{
-		Config:     uint8(cfg.bConfigurationValue),
-		Attributes: uint8(cfg.bmAttributes),
-		MaxPower:   uint8(cfg.MaxPower),
-	}
-
-	var ifaces []C.struct_libusb_interface
-	*(*reflect.SliceHeader)(unsafe.Pointer(&ifaces)) = reflect.SliceHeader{
-		Data: uintptr(unsafe.Pointer(cfg._interface)),
-		Len:  int(cfg.bNumInterfaces),
-		Cap:  int(cfg.bNumInterfaces),
-	}
-	c.Interfaces = make([]InterfaceInfo, 0, len(ifaces))
-	for _, iface := range ifaces {
-		if iface.num_altsetting == 0 {
-			continue
-		}
-
-		var alts []C.struct_libusb_interface_descriptor
-		*(*reflect.SliceHeader)(unsafe.Pointer(&alts)) = reflect.SliceHeader{
-			Data: uintptr(unsafe.Pointer(iface.altsetting)),
-			Len:  int(iface.num_altsetting),
-			Cap:  int(iface.num_altsetting),
-		}
-		descs := make([]InterfaceSetup, 0, len(alts))
-		for _, alt := range alts {
-			i := InterfaceSetup{
-				Number:     uint8(alt.bInterfaceNumber),
-				Alternate:  uint8(alt.bAlternateSetting),
-				IfClass:    uint8(alt.bInterfaceClass),
-				IfSubClass: uint8(alt.bInterfaceSubClass),
-				IfProtocol: uint8(alt.bInterfaceProtocol),
-			}
-			var ends []C.struct_libusb_endpoint_descriptor
-			*(*reflect.SliceHeader)(unsafe.Pointer(&ends)) = reflect.SliceHeader{
-				Data: uintptr(unsafe.Pointer(alt.endpoint)),
-				Len:  int(alt.bNumEndpoints),
-				Cap:  int(alt.bNumEndpoints),
-			}
-			i.Endpoints = make([]EndpointInfo, 0, len(ends))
-			for _, end := range ends {
-				i.Endpoints = append(i.Endpoints, EndpointInfo{
-					Address:       uint8(end.bEndpointAddress),
-					Attributes:    uint8(end.bmAttributes),
-					MaxPacketSize: uint16(end.wMaxPacketSize),
-					//MaxIsoPacket:  uint32(C.libusb_get_max_iso_packet_size(dev, C.uchar(end.bEndpointAddress))),
-					PollInterval: uint8(end.bInterval),
-					RefreshRate:  uint8(end.bRefresh),
-					SynchAddress: uint8(end.bSynchAddress),
-				})
-			}
-			descs = append(descs, i)
-		}
-		c.Interfaces = append(c.Interfaces, InterfaceInfo{
-			Number: descs[0].Number,
-			Setups: descs,
-		})
-	}
-	return c
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/constants.go b/vendor/github.com/karalabe/gousb/usb/constants.go
deleted file mode 100644
index 7f0287d5c..000000000
--- a/vendor/github.com/karalabe/gousb/usb/constants.go
+++ /dev/null
@@ -1,183 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-// #include "libusb.h"
-import "C"
-
-type Class uint8
-
-const (
-	CLASS_PER_INTERFACE Class = C.LIBUSB_CLASS_PER_INTERFACE
-	CLASS_AUDIO         Class = C.LIBUSB_CLASS_AUDIO
-	CLASS_COMM          Class = C.LIBUSB_CLASS_COMM
-	CLASS_HID           Class = C.LIBUSB_CLASS_HID
-	CLASS_PRINTER       Class = C.LIBUSB_CLASS_PRINTER
-	CLASS_PTP           Class = C.LIBUSB_CLASS_PTP
-	CLASS_MASS_STORAGE  Class = C.LIBUSB_CLASS_MASS_STORAGE
-	CLASS_HUB           Class = C.LIBUSB_CLASS_HUB
-	CLASS_DATA          Class = C.LIBUSB_CLASS_DATA
-	CLASS_WIRELESS      Class = C.LIBUSB_CLASS_WIRELESS
-	CLASS_APPLICATION   Class = C.LIBUSB_CLASS_APPLICATION
-	CLASS_VENDOR_SPEC   Class = C.LIBUSB_CLASS_VENDOR_SPEC
-)
-
-var classDescription = map[Class]string{
-	CLASS_PER_INTERFACE: "per-interface",
-	CLASS_AUDIO:         "audio",
-	CLASS_COMM:          "communications",
-	CLASS_HID:           "human interface device",
-	CLASS_PRINTER:       "printer dclass",
-	CLASS_PTP:           "picture transfer protocol",
-	CLASS_MASS_STORAGE:  "mass storage",
-	CLASS_HUB:           "hub",
-	CLASS_DATA:          "data",
-	CLASS_WIRELESS:      "wireless",
-	CLASS_APPLICATION:   "application",
-	CLASS_VENDOR_SPEC:   "vendor-specific",
-}
-
-func (c Class) String() string {
-	return classDescription[c]
-}
-
-type DescriptorType uint8
-
-const (
-	DT_DEVICE    DescriptorType = C.LIBUSB_DT_DEVICE
-	DT_CONFIG    DescriptorType = C.LIBUSB_DT_CONFIG
-	DT_STRING    DescriptorType = C.LIBUSB_DT_STRING
-	DT_INTERFACE DescriptorType = C.LIBUSB_DT_INTERFACE
-	DT_ENDPOINT  DescriptorType = C.LIBUSB_DT_ENDPOINT
-	DT_HID       DescriptorType = C.LIBUSB_DT_HID
-	DT_REPORT    DescriptorType = C.LIBUSB_DT_REPORT
-	DT_PHYSICAL  DescriptorType = C.LIBUSB_DT_PHYSICAL
-	DT_HUB       DescriptorType = C.LIBUSB_DT_HUB
-)
-
-var descriptorTypeDescription = map[DescriptorType]string{
-	DT_DEVICE:    "device",
-	DT_CONFIG:    "configuration",
-	DT_STRING:    "string",
-	DT_INTERFACE: "interface",
-	DT_ENDPOINT:  "endpoint",
-	DT_HID:       "HID",
-	DT_REPORT:    "HID report",
-	DT_PHYSICAL:  "physical",
-	DT_HUB:       "hub",
-}
-
-func (dt DescriptorType) String() string {
-	return descriptorTypeDescription[dt]
-}
-
-type EndpointDirection uint8
-
-const (
-	ENDPOINT_NUM_MASK                   = 0x03
-	ENDPOINT_DIR_IN   EndpointDirection = C.LIBUSB_ENDPOINT_IN
-	ENDPOINT_DIR_OUT  EndpointDirection = C.LIBUSB_ENDPOINT_OUT
-	ENDPOINT_DIR_MASK EndpointDirection = 0x80
-)
-
-var endpointDirectionDescription = map[EndpointDirection]string{
-	ENDPOINT_DIR_IN:  "IN",
-	ENDPOINT_DIR_OUT: "OUT",
-}
-
-func (ed EndpointDirection) String() string {
-	return endpointDirectionDescription[ed]
-}
-
-type TransferType uint8
-
-const (
-	TRANSFER_TYPE_CONTROL     TransferType = C.LIBUSB_TRANSFER_TYPE_CONTROL
-	TRANSFER_TYPE_ISOCHRONOUS TransferType = C.LIBUSB_TRANSFER_TYPE_ISOCHRONOUS
-	TRANSFER_TYPE_BULK        TransferType = C.LIBUSB_TRANSFER_TYPE_BULK
-	TRANSFER_TYPE_INTERRUPT   TransferType = C.LIBUSB_TRANSFER_TYPE_INTERRUPT
-	TRANSFER_TYPE_MASK        TransferType = 0x03
-)
-
-var transferTypeDescription = map[TransferType]string{
-	TRANSFER_TYPE_CONTROL:     "control",
-	TRANSFER_TYPE_ISOCHRONOUS: "isochronous",
-	TRANSFER_TYPE_BULK:        "bulk",
-	TRANSFER_TYPE_INTERRUPT:   "interrupt",
-}
-
-func (tt TransferType) String() string {
-	return transferTypeDescription[tt]
-}
-
-type IsoSyncType uint8
-
-const (
-	ISO_SYNC_TYPE_NONE     IsoSyncType = C.LIBUSB_ISO_SYNC_TYPE_NONE << 2
-	ISO_SYNC_TYPE_ASYNC    IsoSyncType = C.LIBUSB_ISO_SYNC_TYPE_ASYNC << 2
-	ISO_SYNC_TYPE_ADAPTIVE IsoSyncType = C.LIBUSB_ISO_SYNC_TYPE_ADAPTIVE << 2
-	ISO_SYNC_TYPE_SYNC     IsoSyncType = C.LIBUSB_ISO_SYNC_TYPE_SYNC << 2
-	ISO_SYNC_TYPE_MASK     IsoSyncType = 0x0C
-)
-
-var isoSyncTypeDescription = map[IsoSyncType]string{
-	ISO_SYNC_TYPE_NONE:     "unsynchronized",
-	ISO_SYNC_TYPE_ASYNC:    "asynchronous",
-	ISO_SYNC_TYPE_ADAPTIVE: "adaptive",
-	ISO_SYNC_TYPE_SYNC:     "synchronous",
-}
-
-func (ist IsoSyncType) String() string {
-	return isoSyncTypeDescription[ist]
-}
-
-type IsoUsageType uint8
-
-const (
-	ISO_USAGE_TYPE_DATA     IsoUsageType = C.LIBUSB_ISO_USAGE_TYPE_DATA << 4
-	ISO_USAGE_TYPE_FEEDBACK IsoUsageType = C.LIBUSB_ISO_USAGE_TYPE_FEEDBACK << 4
-	ISO_USAGE_TYPE_IMPLICIT IsoUsageType = C.LIBUSB_ISO_USAGE_TYPE_IMPLICIT << 4
-	ISO_USAGE_TYPE_MASK     IsoUsageType = 0x30
-)
-
-var isoUsageTypeDescription = map[IsoUsageType]string{
-	ISO_USAGE_TYPE_DATA:     "data",
-	ISO_USAGE_TYPE_FEEDBACK: "feedback",
-	ISO_USAGE_TYPE_IMPLICIT: "implicit data",
-}
-
-func (iut IsoUsageType) String() string {
-	return isoUsageTypeDescription[iut]
-}
-
-type RequestType uint8
-
-const (
-	REQUEST_TYPE_STANDARD = C.LIBUSB_REQUEST_TYPE_STANDARD
-	REQUEST_TYPE_CLASS    = C.LIBUSB_REQUEST_TYPE_CLASS
-	REQUEST_TYPE_VENDOR   = C.LIBUSB_REQUEST_TYPE_VENDOR
-	REQUEST_TYPE_RESERVED = C.LIBUSB_REQUEST_TYPE_RESERVED
-)
-
-var requestTypeDescription = map[RequestType]string{
-	REQUEST_TYPE_STANDARD: "standard",
-	REQUEST_TYPE_CLASS:    "class",
-	REQUEST_TYPE_VENDOR:   "vendor",
-	REQUEST_TYPE_RESERVED: "reserved",
-}
-
-func (rt RequestType) String() string {
-	return requestTypeDescription[rt]
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/debug.go b/vendor/github.com/karalabe/gousb/usb/debug.go
deleted file mode 100644
index e7de8e522..000000000
--- a/vendor/github.com/karalabe/gousb/usb/debug.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-// To enable internal debugging:
-//   -ldflags "-X github.com/karalabe/gousb/usb.debugInternal true"
-
-import (
-	"io"
-	"io/ioutil"
-	"log" // TODO(kevlar): make a logger
-	"os"
-)
-
-var debug *log.Logger
-var debugInternal string
-
-func init() {
-	var out io.Writer = ioutil.Discard
-	if debugInternal != "" {
-		out = os.Stderr
-	}
-	debug = log.New(out, "usb", log.LstdFlags|log.Lshortfile)
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/descriptor.go b/vendor/github.com/karalabe/gousb/usb/descriptor.go
deleted file mode 100644
index 2551dfc23..000000000
--- a/vendor/github.com/karalabe/gousb/usb/descriptor.go
+++ /dev/null
@@ -1,77 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-/*
-#ifndef OS_WINDOWS
-	#include "os/threads_posix.h"
-#endif
-#include "libusbi.h"
-#include "libusb.h"
-*/
-import "C"
-
-type Descriptor struct {
-	// Bus information
-	Bus     uint8 // The bus on which the device was detected
-	Address uint8 // The address of the device on the bus
-
-	// Version information
-	Spec   BCD // USB Specification Release Number
-	Device BCD // The device version
-
-	// Product information
-	Vendor  ID // The Vendor identifer
-	Product ID // The Product identifier
-
-	// Protocol information
-	Class    uint8 // The class of this device
-	SubClass uint8 // The sub-class (within the class) of this device
-	Protocol uint8 // The protocol (within the sub-class) of this device
-
-	// Configuration information
-	Configs []ConfigInfo
-}
-
-func newDescriptor(dev *C.libusb_device) (*Descriptor, error) {
-	var desc C.struct_libusb_device_descriptor
-	if errno := C.libusb_get_device_descriptor(dev, &desc); errno < 0 {
-		return nil, usbError(errno)
-	}
-
-	// Enumerate configurations
-	var cfgs []ConfigInfo
-	for i := 0; i < int(desc.bNumConfigurations); i++ {
-		var cfg *C.struct_libusb_config_descriptor
-		if errno := C.libusb_get_config_descriptor(dev, C.uint8_t(i), &cfg); errno < 0 {
-			return nil, usbError(errno)
-		}
-		cfgs = append(cfgs, newConfig(dev, cfg))
-		C.libusb_free_config_descriptor(cfg)
-	}
-
-	return &Descriptor{
-		Bus:      uint8(C.libusb_get_bus_number(dev)),
-		Address:  uint8(C.libusb_get_device_address(dev)),
-		Spec:     BCD(desc.bcdUSB),
-		Device:   BCD(desc.bcdDevice),
-		Vendor:   ID(desc.idVendor),
-		Product:  ID(desc.idProduct),
-		Class:    uint8(desc.bDeviceClass),
-		SubClass: uint8(desc.bDeviceSubClass),
-		Protocol: uint8(desc.bDeviceProtocol),
-		Configs:  cfgs,
-	}, nil
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/device.go b/vendor/github.com/karalabe/gousb/usb/device.go
deleted file mode 100644
index b4c4131fa..000000000
--- a/vendor/github.com/karalabe/gousb/usb/device.go
+++ /dev/null
@@ -1,295 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-/*
-#ifndef OS_WINDOWS
-	#include "os/threads_posix.h"
-#endif
-#include "libusbi.h"
-#include "libusb.h"
-*/
-import "C"
-
-import (
-	"fmt"
-	"reflect"
-	"sync"
-	"time"
-	"unsafe"
-)
-
-var DefaultReadTimeout = 1 * time.Second
-var DefaultWriteTimeout = 1 * time.Second
-var DefaultControlTimeout = 250 * time.Millisecond //5 * time.Second
-
-type Device struct {
-	handle *C.libusb_device_handle
-
-	// Embed the device information for easy access
-	*Descriptor
-
-	// Timeouts
-	ReadTimeout    time.Duration
-	WriteTimeout   time.Duration
-	ControlTimeout time.Duration
-
-	// Claimed interfaces
-	lock    *sync.Mutex
-	claimed map[uint8]int
-
-	// Detached kernel interfaces
-	detached map[uint8]int
-}
-
-func newDevice(handle *C.libusb_device_handle, desc *Descriptor) (*Device, error) {
-	ifaces := 0
-	d := &Device{
-		handle:         handle,
-		Descriptor:     desc,
-		ReadTimeout:    DefaultReadTimeout,
-		WriteTimeout:   DefaultWriteTimeout,
-		ControlTimeout: DefaultControlTimeout,
-		lock:           new(sync.Mutex),
-		claimed:        make(map[uint8]int, ifaces),
-		detached:       make(map[uint8]int),
-	}
-
-	if err := d.detachKernelDriver(); err != nil {
-		d.Close()
-		return nil, err
-	}
-
-	return d, nil
-}
-
-// detachKernelDriver detaches any active kernel drivers, if supported by the platform.
-// If there are any errors, like Context.ListDevices, only the final one will be returned.
-func (d *Device) detachKernelDriver() (err error) {
-	for _, cfg := range d.Configs {
-		for _, iface := range cfg.Interfaces {
-			switch activeErr := C.libusb_kernel_driver_active(d.handle, C.int(iface.Number)); activeErr {
-			case C.LIBUSB_ERROR_NOT_SUPPORTED:
-				// no need to do any futher checking, no platform support
-				return
-			case 0:
-				continue
-			case 1:
-				switch detachErr := C.libusb_detach_kernel_driver(d.handle, C.int(iface.Number)); detachErr {
-				case C.LIBUSB_ERROR_NOT_SUPPORTED:
-					// shouldn't ever get here, should be caught by the outer switch
-					return
-				case 0:
-					d.detached[iface.Number]++
-				case C.LIBUSB_ERROR_NOT_FOUND:
-					// this status is returned if libusb's driver is already attached to the device
-					d.detached[iface.Number]++
-				default:
-					err = fmt.Errorf("usb: detach kernel driver: %s", usbError(detachErr))
-				}
-			default:
-				err = fmt.Errorf("usb: active kernel driver check: %s", usbError(activeErr))
-			}
-		}
-	}
-
-	return
-}
-
-// attachKernelDriver re-attaches kernel drivers to any previously detached interfaces, if supported by the platform.
-// If there are any errors, like Context.ListDevices, only the final one will be returned.
-func (d *Device) attachKernelDriver() (err error) {
-	for iface := range d.detached {
-		switch attachErr := C.libusb_attach_kernel_driver(d.handle, C.int(iface)); attachErr {
-		case C.LIBUSB_ERROR_NOT_SUPPORTED:
-			// no need to do any futher checking, no platform support
-			return
-		case 0:
-			continue
-		default:
-			err = fmt.Errorf("usb: attach kernel driver: %s", usbError(attachErr))
-		}
-	}
-
-	return
-}
-
-func (d *Device) Reset() error {
-	if errno := C.libusb_reset_device(d.handle); errno != 0 {
-		return usbError(errno)
-	}
-	return nil
-}
-
-func (d *Device) Control(rType, request uint8, val, idx uint16, data []byte) (int, error) {
-	//log.Printf("control xfer: %d:%d/%d:%d %x", idx, rType, request, val, string(data))
-	dataSlice := (*reflect.SliceHeader)(unsafe.Pointer(&data))
-	n := C.libusb_control_transfer(
-		d.handle,
-		C.uint8_t(rType),
-		C.uint8_t(request),
-		C.uint16_t(val),
-		C.uint16_t(idx),
-		(*C.uchar)(unsafe.Pointer(dataSlice.Data)),
-		C.uint16_t(len(data)),
-		C.uint(d.ControlTimeout/time.Millisecond))
-	if n < 0 {
-		return int(n), usbError(n)
-	}
-	return int(n), nil
-}
-
-// ActiveConfig returns the config id (not the index) of the active configuration.
-// This corresponds to the ConfigInfo.Config field.
-func (d *Device) ActiveConfig() (uint8, error) {
-	var cfg C.int
-	if errno := C.libusb_get_configuration(d.handle, &cfg); errno < 0 {
-		return 0, usbError(errno)
-	}
-	return uint8(cfg), nil
-}
-
-// SetConfig attempts to change the active configuration.
-// The cfg provided is the config id (not the index) of the configuration to set,
-// which corresponds to the ConfigInfo.Config field.
-func (d *Device) SetConfig(cfg uint8) error {
-	if errno := C.libusb_set_configuration(d.handle, C.int(cfg)); errno < 0 {
-		return usbError(errno)
-	}
-	return nil
-}
-
-// Close the device.
-func (d *Device) Close() error {
-	if d.handle == nil {
-		return fmt.Errorf("usb: double close on device")
-	}
-	d.lock.Lock()
-	defer d.lock.Unlock()
-	for iface := range d.claimed {
-		C.libusb_release_interface(d.handle, C.int(iface))
-	}
-	d.attachKernelDriver()
-	C.libusb_close(d.handle)
-	d.handle = nil
-	return nil
-}
-
-func (d *Device) OpenEndpoint(conf, iface, setup, epoint uint8) (Endpoint, error) {
-	end := &endpoint{
-		Device: d,
-	}
-
-	var setAlternate bool
-	for _, c := range d.Configs {
-		if c.Config != conf {
-			continue
-		}
-		debug.Printf("found conf: %#v\n", c)
-		for _, i := range c.Interfaces {
-			if i.Number != iface {
-				continue
-			}
-			debug.Printf("found iface: %#v\n", i)
-			for i, s := range i.Setups {
-				if s.Alternate != setup {
-					continue
-				}
-				setAlternate = i != 0
-
-				debug.Printf("found setup: %#v [default: %v]\n", s, !setAlternate)
-				for _, e := range s.Endpoints {
-					debug.Printf("ep %02x search: %#v\n", epoint, s)
-					if e.Address != epoint {
-						continue
-					}
-					end.InterfaceSetup = s
-					end.EndpointInfo = e
-					switch tt := TransferType(e.Attributes) & TRANSFER_TYPE_MASK; tt {
-					case TRANSFER_TYPE_BULK:
-						end.xfer = bulk_xfer
-					case TRANSFER_TYPE_INTERRUPT:
-						end.xfer = interrupt_xfer
-					case TRANSFER_TYPE_ISOCHRONOUS:
-						end.xfer = isochronous_xfer
-					default:
-						return nil, fmt.Errorf("usb: %s transfer is unsupported", tt)
-					}
-					goto found
-				}
-				return nil, fmt.Errorf("usb: unknown endpoint %02x", epoint)
-			}
-			return nil, fmt.Errorf("usb: unknown setup %02x", setup)
-		}
-		return nil, fmt.Errorf("usb: unknown interface %02x", iface)
-	}
-	return nil, fmt.Errorf("usb: unknown configuration %02x", conf)
-
-found:
-
-	// Set the configuration
-	var activeConf C.int
-	if errno := C.libusb_get_configuration(d.handle, &activeConf); errno < 0 {
-		return nil, fmt.Errorf("usb: getcfg: %s", usbError(errno))
-	}
-	if int(activeConf) != int(conf) {
-		if errno := C.libusb_set_configuration(d.handle, C.int(conf)); errno < 0 {
-			return nil, fmt.Errorf("usb: setcfg: %s", usbError(errno))
-		}
-	}
-
-	// Claim the interface
-	if errno := C.libusb_claim_interface(d.handle, C.int(iface)); errno < 0 {
-		return nil, fmt.Errorf("usb: claim: %s", usbError(errno))
-	}
-
-	// Increment the claim count
-	d.lock.Lock()
-	d.claimed[iface]++
-	d.lock.Unlock() // unlock immediately because the next calls may block
-
-	// Choose the alternate
-	if setAlternate {
-		if errno := C.libusb_set_interface_alt_setting(d.handle, C.int(iface), C.int(setup)); errno < 0 {
-			debug.Printf("altsetting error: %s", usbError(errno))
-			return nil, fmt.Errorf("usb: setalt: %s", usbError(errno))
-		}
-	}
-
-	return end, nil
-}
-
-func (d *Device) GetStringDescriptor(desc_index int) (string, error) {
-
-	// allocate 200-byte array limited the length of string descriptor
-	goBuffer := make([]byte, 200)
-
-	// get string descriptor from libusb. if errno < 0 then there are any errors.
-	// if errno >= 0; it is a length of result string descriptor
-	errno := C.libusb_get_string_descriptor_ascii(
-		d.handle,
-		C.uint8_t(desc_index),
-		(*C.uchar)(unsafe.Pointer(&goBuffer[0])),
-		200)
-
-	// if any errors occur
-	if errno < 0 {
-		return "", fmt.Errorf("usb: getstr: %s", usbError(errno))
-	}
-	// convert slice of byte to string with limited length from errno
-	stringDescriptor := string(goBuffer[:errno])
-
-	return stringDescriptor, nil
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/endpoint.go b/vendor/github.com/karalabe/gousb/usb/endpoint.go
deleted file mode 100644
index 12b4ccf95..000000000
--- a/vendor/github.com/karalabe/gousb/usb/endpoint.go
+++ /dev/null
@@ -1,100 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-// #include "libusb.h"
-import "C"
-
-import (
-	"fmt"
-	"reflect"
-	"time"
-	"unsafe"
-)
-
-type Endpoint interface {
-	Read(b []byte) (int, error)
-	Write(b []byte) (int, error)
-	Interface() InterfaceSetup
-	Info() EndpointInfo
-}
-
-type endpoint struct {
-	*Device
-	InterfaceSetup
-	EndpointInfo
-	xfer func(*endpoint, []byte, time.Duration) (int, error)
-}
-
-func (e *endpoint) Read(buf []byte) (int, error) {
-	if EndpointDirection(e.Address)&ENDPOINT_DIR_MASK != ENDPOINT_DIR_IN {
-		return 0, fmt.Errorf("usb: read: not an IN endpoint")
-	}
-
-	return e.xfer(e, buf, e.ReadTimeout)
-}
-
-func (e *endpoint) Write(buf []byte) (int, error) {
-	if EndpointDirection(e.Address)&ENDPOINT_DIR_MASK != ENDPOINT_DIR_OUT {
-		return 0, fmt.Errorf("usb: write: not an OUT endpoint")
-	}
-
-	return e.xfer(e, buf, e.WriteTimeout)
-}
-
-func (e *endpoint) Interface() InterfaceSetup { return e.InterfaceSetup }
-func (e *endpoint) Info() EndpointInfo        { return e.EndpointInfo }
-
-// TODO(kevlar): (*Endpoint).Close
-
-func bulk_xfer(e *endpoint, buf []byte, timeout time.Duration) (int, error) {
-	if len(buf) == 0 {
-		return 0, nil
-	}
-
-	data := (*reflect.SliceHeader)(unsafe.Pointer(&buf)).Data
-
-	var cnt C.int
-	if errno := C.libusb_bulk_transfer(
-		e.handle,
-		C.uchar(e.Address),
-		(*C.uchar)(unsafe.Pointer(data)),
-		C.int(len(buf)),
-		&cnt,
-		C.uint(timeout/time.Millisecond)); errno < 0 {
-		return 0, usbError(errno)
-	}
-	return int(cnt), nil
-}
-
-func interrupt_xfer(e *endpoint, buf []byte, timeout time.Duration) (int, error) {
-	if len(buf) == 0 {
-		return 0, nil
-	}
-
-	data := (*reflect.SliceHeader)(unsafe.Pointer(&buf)).Data
-
-	var cnt C.int
-	if errno := C.libusb_interrupt_transfer(
-		e.handle,
-		C.uchar(e.Address),
-		(*C.uchar)(unsafe.Pointer(data)),
-		C.int(len(buf)),
-		&cnt,
-		C.uint(timeout/time.Millisecond)); errno < 0 {
-		return 0, usbError(errno)
-	}
-	return int(cnt), nil
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/error.go b/vendor/github.com/karalabe/gousb/usb/error.go
deleted file mode 100644
index 30d47bce3..000000000
--- a/vendor/github.com/karalabe/gousb/usb/error.go
+++ /dev/null
@@ -1,92 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-import (
-	"fmt"
-)
-
-// #include "libusb.h"
-import "C"
-
-type usbError C.int
-
-func (e usbError) Error() string {
-	return fmt.Sprintf("libusb: %s [code %d]", usbErrorString[e], int(e))
-}
-
-const (
-	SUCCESS             usbError = C.LIBUSB_SUCCESS
-	ERROR_IO            usbError = C.LIBUSB_ERROR_IO
-	ERROR_INVALID_PARAM usbError = C.LIBUSB_ERROR_INVALID_PARAM
-	ERROR_ACCESS        usbError = C.LIBUSB_ERROR_ACCESS
-	ERROR_NO_DEVICE     usbError = C.LIBUSB_ERROR_NO_DEVICE
-	ERROR_NOT_FOUND     usbError = C.LIBUSB_ERROR_NOT_FOUND
-	ERROR_BUSY          usbError = C.LIBUSB_ERROR_BUSY
-	ERROR_TIMEOUT       usbError = C.LIBUSB_ERROR_TIMEOUT
-	ERROR_OVERFLOW      usbError = C.LIBUSB_ERROR_OVERFLOW
-	ERROR_PIPE          usbError = C.LIBUSB_ERROR_PIPE
-	ERROR_INTERRUPTED   usbError = C.LIBUSB_ERROR_INTERRUPTED
-	ERROR_NO_MEM        usbError = C.LIBUSB_ERROR_NO_MEM
-	ERROR_NOT_SUPPORTED usbError = C.LIBUSB_ERROR_NOT_SUPPORTED
-	ERROR_OTHER         usbError = C.LIBUSB_ERROR_OTHER
-)
-
-var usbErrorString = map[usbError]string{
-	C.LIBUSB_SUCCESS:             "success",
-	C.LIBUSB_ERROR_IO:            "i/o error",
-	C.LIBUSB_ERROR_INVALID_PARAM: "invalid param",
-	C.LIBUSB_ERROR_ACCESS:        "bad access",
-	C.LIBUSB_ERROR_NO_DEVICE:     "no device",
-	C.LIBUSB_ERROR_NOT_FOUND:     "not found",
-	C.LIBUSB_ERROR_BUSY:          "device or resource busy",
-	C.LIBUSB_ERROR_TIMEOUT:       "timeout",
-	C.LIBUSB_ERROR_OVERFLOW:      "overflow",
-	C.LIBUSB_ERROR_PIPE:          "pipe error",
-	C.LIBUSB_ERROR_INTERRUPTED:   "interrupted",
-	C.LIBUSB_ERROR_NO_MEM:        "out of memory",
-	C.LIBUSB_ERROR_NOT_SUPPORTED: "not supported",
-	C.LIBUSB_ERROR_OTHER:         "unknown error",
-}
-
-type TransferStatus uint8
-
-const (
-	LIBUSB_TRANSFER_COMPLETED TransferStatus = C.LIBUSB_TRANSFER_COMPLETED
-	LIBUSB_TRANSFER_ERROR     TransferStatus = C.LIBUSB_TRANSFER_ERROR
-	LIBUSB_TRANSFER_TIMED_OUT TransferStatus = C.LIBUSB_TRANSFER_TIMED_OUT
-	LIBUSB_TRANSFER_CANCELLED TransferStatus = C.LIBUSB_TRANSFER_CANCELLED
-	LIBUSB_TRANSFER_STALL     TransferStatus = C.LIBUSB_TRANSFER_STALL
-	LIBUSB_TRANSFER_NO_DEVICE TransferStatus = C.LIBUSB_TRANSFER_NO_DEVICE
-	LIBUSB_TRANSFER_OVERFLOW  TransferStatus = C.LIBUSB_TRANSFER_OVERFLOW
-)
-
-var transferStatusDescription = map[TransferStatus]string{
-	LIBUSB_TRANSFER_COMPLETED: "transfer completed without error",
-	LIBUSB_TRANSFER_ERROR:     "transfer failed",
-	LIBUSB_TRANSFER_TIMED_OUT: "transfer timed out",
-	LIBUSB_TRANSFER_CANCELLED: "transfer was cancelled",
-	LIBUSB_TRANSFER_STALL:     "halt condition detected (endpoint stalled) or control request not supported",
-	LIBUSB_TRANSFER_NO_DEVICE: "device was disconnected",
-	LIBUSB_TRANSFER_OVERFLOW:  "device sent more data than requested",
-}
-
-func (ts TransferStatus) String() string {
-	return transferStatusDescription[ts]
-}
-
-func (ts TransferStatus) Error() string {
-	return "libusb: " + ts.String()
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/iso.c b/vendor/github.com/karalabe/gousb/usb/iso.c
deleted file mode 100644
index 054486318..000000000
--- a/vendor/github.com/karalabe/gousb/usb/iso.c
+++ /dev/null
@@ -1,79 +0,0 @@
-#include "libusb.h"
-#include <stdio.h>
-#include <string.h>
-
-void print_xfer(struct libusb_transfer *xfer);
-void iso_callback(void *);
-
-void callback(struct libusb_transfer *xfer) {
-	//printf("Callback!\n");
-	//print_xfer(xfer);
-	iso_callback(xfer->user_data);
-}
-
-int submit(struct libusb_transfer *xfer) {
-	xfer->callback = &callback;
-	xfer->status = -1;
-	//print_xfer(xfer);
-	//printf("Transfer submitted\n");
-
-	/* fake
-	strcpy(xfer->buffer, "hello");
-	xfer->actual_length = 5;
-	callback(xfer);
-	return 0; */
-	return libusb_submit_transfer(xfer);
-}
-
-void print_xfer(struct libusb_transfer *xfer) {
-	int i;
-
-	printf("Transfer:\n");
-	printf("  dev_handle:   %p\n", xfer->dev_handle);
-	printf("  flags:        %08x\n", xfer->flags);
-	printf("  endpoint:     %x\n", xfer->endpoint);
-	printf("  type:         %x\n", xfer->type);
-	printf("  timeout:      %dms\n", xfer->timeout);
-	printf("  status:       %x\n", xfer->status);
-	printf("  length:       %d (act: %d)\n", xfer->length, xfer->actual_length);
-	printf("  callback:     %p\n", xfer->callback);
-	printf("  user_data:    %p\n", xfer->user_data);
-	printf("  buffer:       %p\n", xfer->buffer);
-	printf("  num_iso_pkts: %d\n", xfer->num_iso_packets);
-	printf("  packets:\n");
-	for (i = 0; i < xfer->num_iso_packets; i++) {
-		printf("    [%04d] %d (act: %d) %x\n", i,
-			xfer->iso_packet_desc[i].length,
-			xfer->iso_packet_desc[i].actual_length,
-			xfer->iso_packet_desc[i].status);
-	}
-}
-
-int extract_data(struct libusb_transfer *xfer, void *raw, int max, unsigned char *status) {
-	int i;
-	int copied = 0;
-	unsigned char *in = xfer->buffer;
-	unsigned char *out = raw;
-	for (i = 0; i < xfer->num_iso_packets; i++) {
-		struct libusb_iso_packet_descriptor pkt = xfer->iso_packet_desc[i];
-
-		// Copy the data
-		int len = pkt.actual_length;
-		if (len > max) {
-			len = max;
-		}
-		memcpy(out, in, len);
-		copied += len;
-
-		// Increment offsets
-		in += pkt.length;
-		out += len;
-
-		// Extract first error
-		if (pkt.status == 0 || *status != 0) {
-			continue;
-		}
-		*status = pkt.status;
-	}
-	return copied;
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/iso.go b/vendor/github.com/karalabe/gousb/usb/iso.go
deleted file mode 100644
index 1ba694e0e..000000000
--- a/vendor/github.com/karalabe/gousb/usb/iso.go
+++ /dev/null
@@ -1,148 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-/*
-#include "libusb.h"
-
-int submit(struct libusb_transfer *xfer);
-void print_xfer(struct libusb_transfer *xfer);
-int extract_data(struct libusb_transfer *xfer, void *data, int max, unsigned char *status);
-*/
-import "C"
-
-import (
-	"fmt"
-	"log"
-	"time"
-	"unsafe"
-)
-
-//export iso_callback
-func iso_callback(cptr unsafe.Pointer) {
-	ch := *(*chan struct{})(cptr)
-	close(ch)
-}
-
-func (end *endpoint) allocTransfer() *Transfer {
-	// Use libusb_get_max_iso_packet_size ?
-	const (
-		iso_packets = 8       // 128 // 242
-		packet_size = 2 * 960 // 1760
-	)
-
-	xfer := C.libusb_alloc_transfer(C.int(iso_packets))
-	if xfer == nil {
-		log.Printf("usb: transfer allocation failed?!")
-		return nil
-	}
-
-	buf := make([]byte, iso_packets*packet_size)
-	done := make(chan struct{}, 1)
-
-	xfer.dev_handle = end.Device.handle
-	xfer.endpoint = C.uchar(end.Address)
-	xfer._type = C.LIBUSB_TRANSFER_TYPE_ISOCHRONOUS
-
-	xfer.buffer = (*C.uchar)((unsafe.Pointer)(&buf[0]))
-	xfer.length = C.int(len(buf))
-	xfer.num_iso_packets = iso_packets
-
-	C.libusb_set_iso_packet_lengths(xfer, packet_size)
-	/*
-		pkts := *(*[]C.struct_libusb_packet_descriptor)(unsafe.Pointer(&reflect.SliceHeader{
-			Data: uintptr(unsafe.Pointer(&xfer.iso_packet_desc)),
-			Len:  iso_packets,
-			Cap:  iso_packets,
-		}))
-	*/
-
-	t := &Transfer{
-		xfer: xfer,
-		done: done,
-		buf:  buf,
-	}
-	xfer.user_data = (unsafe.Pointer)(&t.done)
-
-	return t
-}
-
-type Transfer struct {
-	xfer *C.struct_libusb_transfer
-	pkts []*C.struct_libusb_packet_descriptor
-	done chan struct{}
-	buf  []byte
-}
-
-func (t *Transfer) Submit(timeout time.Duration) error {
-	//log.Printf("iso: submitting %#v", t.xfer)
-	t.xfer.timeout = C.uint(timeout / time.Millisecond)
-	if errno := C.submit(t.xfer); errno < 0 {
-		return usbError(errno)
-	}
-	return nil
-}
-
-func (t *Transfer) Wait(b []byte) (n int, err error) {
-	select {
-	case <-time.After(10 * time.Second):
-		return 0, fmt.Errorf("wait timed out after 10s")
-	case <-t.done:
-	}
-	// Non-iso transfers:
-	//n = int(t.xfer.actual_length)
-	//copy(b, ((*[1 << 16]byte)(unsafe.Pointer(t.xfer.buffer)))[:n])
-
-	//C.print_xfer(t.xfer)
-	/*
-		buf, offset := ((*[1 << 16]byte)(unsafe.Pointer(t.xfer.buffer))), 0
-		for i, pkt := range *t.pkts {
-			log.Printf("Type is %T", t.pkts)
-			n += copy(b[n:], buf[offset:][:pkt.actual_length])
-			offset += pkt.Length
-			if pkt.status != 0 && err == nil {
-				err = error(TransferStatus(pkt.status))
-			}
-		}
-	*/
-	var status uint8
-	n = int(C.extract_data(t.xfer, unsafe.Pointer(&b[0]), C.int(len(b)), (*C.uchar)(unsafe.Pointer(&status))))
-	if status != 0 {
-		err = TransferStatus(status)
-	}
-	return n, err
-}
-
-func (t *Transfer) Close() error {
-	C.libusb_free_transfer(t.xfer)
-	return nil
-}
-
-func isochronous_xfer(e *endpoint, buf []byte, timeout time.Duration) (int, error) {
-	t := e.allocTransfer()
-	defer t.Close()
-
-	if err := t.Submit(timeout); err != nil {
-		log.Printf("iso: xfer failed to submit: %s", err)
-		return 0, err
-	}
-
-	n, err := t.Wait(buf)
-	if err != nil {
-		log.Printf("iso: xfer failed: %s", err)
-		return 0, err
-	}
-	return n, err
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/misc.go b/vendor/github.com/karalabe/gousb/usb/misc.go
deleted file mode 100644
index 6e25431bf..000000000
--- a/vendor/github.com/karalabe/gousb/usb/misc.go
+++ /dev/null
@@ -1,47 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-import (
-	"fmt"
-)
-
-type BCD uint16
-
-const (
-	USB_2_0 BCD = 0x0200
-	USB_1_1 BCD = 0x0110
-	USB_1_0 BCD = 0x0100
-)
-
-func (d BCD) Int() (i int) {
-	ten := 1
-	for o := uint(0); o < 4; o++ {
-		n := ((0xF << (o * 4)) & d) >> (o * 4)
-		i += int(n) * ten
-		ten *= 10
-	}
-	return
-}
-
-func (d BCD) String() string {
-	return fmt.Sprintf("%02x.%02x", int(d>>8), int(d&0xFF))
-}
-
-type ID uint16
-
-func (id ID) String() string {
-	return fmt.Sprintf("%04x", int(id))
-}
diff --git a/vendor/github.com/karalabe/gousb/usb/usb.go b/vendor/github.com/karalabe/gousb/usb/usb.go
deleted file mode 100644
index 366827e69..000000000
--- a/vendor/github.com/karalabe/gousb/usb/usb.go
+++ /dev/null
@@ -1,178 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package usb provides a wrapper around libusb-1.0.
-package usb
-
-/*
-#cgo CFLAGS: -I../internal/libusb/libusb
-#cgo CFLAGS: -DDEFAULT_VISIBILITY=""
-#cgo linux CFLAGS: -DOS_LINUX -D_GNU_SOURCE -DPOLL_NFDS_TYPE=int
-#cgo darwin CFLAGS: -DOS_DARWIN -DPOLL_NFDS_TYPE=int
-#cgo darwin LDFLAGS: -framework CoreFoundation -framework IOKit -lobjc
-#cgo openbsd CFLAGS: -DOS_OPENBSD -DPOLL_NFDS_TYPE=int
-#cgo windows CFLAGS: -DOS_WINDOWS -DUSE_USBDK -DPOLL_NFDS_TYPE=int
-
-#if defined(OS_LINUX) || defined(OS_DARWIN) || defined(OS_OPENBSD)
-	#include <sys/poll.h>
-	#include "os/threads_posix.c"
-	#include "os/poll_posix.c"
-#elif defined(OS_WINDOWS)
-	#include "os/threads_windows.c"
-	#include "os/poll_windows.c"
-#endif
-
-#ifdef OS_LINUX
-	#include "os/linux_usbfs.c"
-	#include "os/linux_netlink.c"
-#elif OS_DARWIN
-	#include "os/darwin_usb.c"
-#elif OS_OPENBSD
-	#include "os/openbsd_usb.c"
-#elif OS_WINDOWS
-	#include "os/windows_nt_common.c"
-	#include "os/windows_usbdk.c"
-#endif
-
-#include "core.c"
-#include "descriptor.c"
-#include "hotplug.c"
-#include "io.c"
-#include "strerror.c"
-#include "sync.c"
-*/
-import "C"
-
-import (
-	"log"
-	"reflect"
-	"unsafe"
-)
-
-type Context struct {
-	ctx  *C.libusb_context
-	done chan struct{}
-}
-
-func (c *Context) Debug(level int) {
-	C.libusb_set_debug(c.ctx, C.int(level))
-}
-
-func NewContext() (*Context, error) {
-	c := &Context{
-		done: make(chan struct{}),
-	}
-
-	if errno := C.libusb_init(&c.ctx); errno != 0 {
-		return nil, usbError(errno)
-	}
-
-	go func() {
-		tv := C.struct_timeval{
-			tv_sec:  0,
-			tv_usec: 100000,
-		}
-		for {
-			select {
-			case <-c.done:
-				return
-			default:
-			}
-			if errno := C.libusb_handle_events_timeout_completed(c.ctx, &tv, nil); errno < 0 {
-				log.Printf("handle_events: error: %s", usbError(errno))
-				continue
-			}
-			//log.Printf("handle_events returned")
-		}
-	}()
-
-	return c, nil
-}
-
-// ListDevices calls each with each enumerated device.
-// If the function returns true, the device is opened and a Device is returned if the operation succeeds.
-// Every Device returned (whether an error is also returned or not) must be closed.
-// If there are any errors enumerating the devices,
-// the final one is returned along with any successfully opened devices.
-func (c *Context) ListDevices(each func(desc *Descriptor) bool) ([]*Device, error) {
-	var list **C.libusb_device
-	cnt := C.libusb_get_device_list(c.ctx, &list)
-	if cnt < 0 {
-		return nil, usbError(cnt)
-	}
-	defer C.libusb_free_device_list(list, 1)
-
-	var slice []*C.libusb_device
-	*(*reflect.SliceHeader)(unsafe.Pointer(&slice)) = reflect.SliceHeader{
-		Data: uintptr(unsafe.Pointer(list)),
-		Len:  int(cnt),
-		Cap:  int(cnt),
-	}
-
-	var reterr error
-	var ret []*Device
-	for _, dev := range slice {
-		desc, err := newDescriptor(dev)
-		if err != nil {
-			reterr = err
-			continue
-		}
-
-		if each(desc) {
-			var handle *C.libusb_device_handle
-			if errno := C.libusb_open(dev, &handle); errno != 0 {
-				reterr = usbError(errno)
-				continue
-			}
-			if dev, err := newDevice(handle, desc); err != nil {
-				reterr = err
-			} else {
-				ret = append(ret, dev)
-			}
-		}
-	}
-	return ret, reterr
-}
-
-// OpenDeviceWithVidPid opens Device from specific VendorId and ProductId.
-// If there are any errors, it'll returns at second value.
-func (c *Context) OpenDeviceWithVidPid(vid, pid int) (*Device, error) {
-
-	handle := C.libusb_open_device_with_vid_pid(c.ctx, (C.uint16_t)(vid), (C.uint16_t)(pid))
-	if handle == nil {
-		return nil, ERROR_NOT_FOUND
-	}
-
-	dev := C.libusb_get_device(handle)
-	if dev == nil {
-		return nil, ERROR_NO_DEVICE
-	}
-
-	desc, err := newDescriptor(dev)
-
-	// return an error from nil-handle and nil-device
-	if err != nil {
-		return nil, err
-	}
-	return newDevice(handle, desc)
-}
-
-func (c *Context) Close() error {
-	close(c.done)
-	if c.ctx != nil {
-		C.libusb_exit(c.ctx)
-	}
-	c.ctx = nil
-	return nil
-}
diff --git a/vendor/github.com/karalabe/hid/LICENSE.md b/vendor/github.com/karalabe/hid/LICENSE.md
new file mode 100644
index 000000000..025ad35e9
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/LICENSE.md
@@ -0,0 +1,8 @@
+The components of `hid` are licensed as such:
+
+ * `hidapi` is released under the [3-clause BSD](https://github.com/signal11/hidapi/blob/master/LICENSE-bsd.txt) license.
+ * `libusb` is released under the [GNU GPL 2.1](https://github.com/libusb/libusb/blob/master/COPYING)license.
+ * `go.hid` is released under the [2-clause BSD](https://github.com/GeertJohan/go.hid/blob/master/LICENSE) license.
+ * `gowchar` is released under the [3-clause BSD](https://github.com/orofarne/gowchar/blob/master/LICENSE) license.
+
+Given the above, `hid` is licensed under GNU GPL 2.1 or later on Linux and 3-clause BSD on other platforms.
diff --git a/vendor/github.com/karalabe/hid/README.md b/vendor/github.com/karalabe/hid/README.md
new file mode 100644
index 000000000..2c3cbb8ae
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/README.md
@@ -0,0 +1,41 @@
+[![GoDoc][docimg]][docurl]
+
+[docimg]: https://godoc.org/github.com/karalabe/hid?status.svg
+[docurl]: https://godoc.org/github.com/karalabe/hid
+
+# Gopher Interface Devices (USB HID)
+
+The `hid` package is a cross platform library for accessing and communicating with USB Human Interface
+Devices (HID). It is an alternative package to [`gousb`](https://github.com/karalabe/gousb) for use
+cases where devices support this ligher mode of operation (e.g. input devices, hardware crypto wallets).
+
+The package wraps [`hidapi`](https://github.com/signal11/hidapi) for accessing OS specific USB HID APIs
+directly instead of using low level USB constructs, which might have permission issues on some platforms.
+On Linux the package also wraps [`libusb`](https://github.com/libusb/libusb). Both of these dependencies
+are vendored directly into the repository and wrapped using CGO, making the `hid` package self-contained
+and go-gettable.
+
+Supported platforms at the moment are Linux, macOS and Windows (exclude constraints are also specified
+for Android and iOS to allow smoother vendoring into cross platform projects).
+
+## Acknowledgements
+
+Although the `hid` package is an implementation from scratch, it was heavily inspired by the existing
+[`go.hid`](https://github.com/GeertJohan/go.hid) library, which seems abandoned since 2015; is incompatible
+with Go 1.6+; and has various external dependencies. Given its inspirational roots, I thought it important
+to give credit to the author of said package too.
+
+Wide character support in the `hid` package is done via the [`gowchar`](https://github.com/orofarne/gowchar)
+library, unmaintained since 2013; non buildable with a modern Go release and failing `go vet` checks. As
+such, `gowchar` was also vendored in inline (copyright headers and origins preserved).
+
+## License
+
+The components of `hid` are licensed as such:
+
+ * `hidapi` is released under the [3-clause BSD](https://github.com/signal11/hidapi/blob/master/LICENSE-bsd.txt) license.
+ * `libusb` is released under the [GNU GPL 2.1](https://github.com/libusb/libusb/blob/master/COPYING)license.
+ * `go.hid` is released under the [2-clause BSD](https://github.com/GeertJohan/go.hid/blob/master/LICENSE) license.
+ * `gowchar` is released under the [3-clause BSD](https://github.com/orofarne/gowchar/blob/master/LICENSE) license.
+
+Given the above, `hid` is licensed under GNU GPL 2.1 or later on Linux and 3-clause BSD on other platforms.
diff --git a/vendor/github.com/karalabe/hid/hid.go b/vendor/github.com/karalabe/hid/hid.go
new file mode 100644
index 000000000..be75f949d
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hid.go
@@ -0,0 +1,37 @@
+// hid - Gopher Interface Devices (USB HID)
+// Copyright (c) 2017 Péter Szilágyi. All rights reserved.
+//
+// This file is released under the 3-clause BSD license. Note however that Linux
+// support depends on libusb, released under GNU GPL 2.1 or later.
+
+// Package hid provides an interface for USB HID devices.
+package hid
+
+import "errors"
+
+// ErrDeviceClosed is returned for operations where the device closed before or
+// during the execution.
+var ErrDeviceClosed = errors.New("hid: device closed")
+
+// ErrUnsupportedPlatform is returned for all operations where the underlying
+// operating system is not supported by the library.
+var ErrUnsupportedPlatform = errors.New("hid: unsupported platform")
+
+// DeviceInfo is a hidapi info structure.
+type DeviceInfo struct {
+	Path         string // Platform-specific device path
+	VendorID     uint16 // Device Vendor ID
+	ProductID    uint16 // Device Product ID
+	Release      uint16 // Device Release Number in binary-coded decimal, also known as Device Version Number
+	Serial       string // Serial Number
+	Manufacturer string // Manufacturer String
+	Product      string // Product string
+	UsagePage    uint16 // Usage Page for this Device/Interface (Windows/Mac only)
+	Usage        uint16 // Usage for this Device/Interface (Windows/Mac only)
+
+	// The USB interface which this logical device
+	// represents. Valid on both Linux implementations
+	// in all cases, and valid on the Windows implementation
+	// only if the device contains more than one interface.
+	Interface int
+}
diff --git a/vendor/github.com/karalabe/hid/hid_disabled.go b/vendor/github.com/karalabe/hid/hid_disabled.go
new file mode 100644
index 000000000..0798bad1b
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hid_disabled.go
@@ -0,0 +1,53 @@
+// hid - Gopher Interface Devices (USB HID)
+// Copyright (c) 2017 Péter Szilágyi. All rights reserved.
+//
+// This file is released under the 3-clause BSD license. Note however that Linux
+// support depends on libusb, released under GNU GPL 2.1 or later.
+
+// +build !linux
+// +build !darwin ios
+// +build !windows
+
+package hid
+
+// Supported returns whether this platform is supported by the HID library or not.
+// The goal of this method is to allow programatically handling platforms that do
+// not support USB HID and not having to fall back to build constraints.
+func Supported() bool {
+	return false
+}
+
+// Enumerate returns a list of all the HID devices attached to the system which
+// match the vendor and product id. On platforms that this file implements the
+// function is a noop and returns an empty list always.
+func Enumerate(vendorID uint16, productID uint16) []DeviceInfo {
+	return nil
+}
+
+// Device is a live HID USB connected device handle. On platforms that this file
+// implements the type lacks the actual HID device and all methods are noop.
+type Device struct {
+	DeviceInfo // Embed the infos for easier access
+}
+
+// Open connects to an HID device by its path name. On platforms that this file
+// implements the method just returns an error.
+func (info DeviceInfo) Open() (*Device, error) {
+	return nil, ErrUnsupportedPlatform
+}
+
+// Close releases the HID USB device handle. On platforms that this file implements
+// the method is just a noop.
+func (dev *Device) Close() {}
+
+// Write sends an output report to a HID device. On platforms that this file
+// implements the method just returns an error.
+func (dev *Device) Write(b []byte) (int, error) {
+	return 0, ErrUnsupportedPlatform
+}
+
+// Read retrieves an input report from a HID device. On platforms that this file
+// implements the method just returns an error.
+func (dev *Device) Read(b []byte) (int, error) {
+	return 0, ErrUnsupportedPlatform
+}
diff --git a/vendor/github.com/karalabe/hid/hid_enabled.go b/vendor/github.com/karalabe/hid/hid_enabled.go
new file mode 100644
index 000000000..3bc0ff381
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hid_enabled.go
@@ -0,0 +1,216 @@
+// hid - Gopher Interface Devices (USB HID)
+// Copyright (c) 2017 Péter Szilágyi. All rights reserved.
+//
+// This file is released under the 3-clause BSD license. Note however that Linux
+// support depends on libusb, released under GNU GPL 2.1 or later.
+
+// +build !ios
+// +build linux darwin windows
+
+package hid
+
+/*
+#cgo CFLAGS: -I./hidapi/hidapi
+
+#cgo linux CFLAGS: -I./libusb/libusb -DDEFAULT_VISIBILITY="" -DOS_LINUX -D_GNU_SOURCE -DPOLL_NFDS_TYPE=int
+#cgo darwin CFLAGS: -DOS_DARWIN
+#cgo darwin LDFLAGS: -framework CoreFoundation -framework IOKit
+#cgo windows CFLAGS: -DOS_WINDOWS
+#cgo windows LDFLAGS: -lsetupapi
+
+#ifdef OS_LINUX
+	#include <sys/poll.h>
+	#include "os/threads_posix.c"
+	#include "os/poll_posix.c"
+
+	#include "os/linux_usbfs.c"
+	#include "os/linux_netlink.c"
+
+	#include "core.c"
+	#include "descriptor.c"
+	#include "hotplug.c"
+	#include "io.c"
+	#include "strerror.c"
+	#include "sync.c"
+
+	#include "hidapi/libusb/hid.c"
+#elif OS_DARWIN
+	#include "hidapi/mac/hid.c"
+#elif OS_WINDOWS
+	#include "hidapi/windows/hid.c"
+#endif
+*/
+import "C"
+import (
+	"errors"
+	"runtime"
+	"sync"
+	"unsafe"
+)
+
+func init() {
+	// Initialize the HIDAPI library
+	C.hid_init()
+}
+
+// Supported returns whether this platform is supported by the HID library or not.
+// The goal of this method is to allow programatically handling platforms that do
+// not support USB HID and not having to fall back to build constraints.
+func Supported() bool {
+	return true
+}
+
+// Enumerate returns a list of all the HID devices attached to the system which
+// match the vendor and product id:
+//  - If the vendor id is set to 0 then any vendor matches.
+//  - If the product id is set to 0 then any product matches.
+//  - If the vendor and product id are both 0, all HID devices are returned.
+func Enumerate(vendorID uint16, productID uint16) []DeviceInfo {
+	// Gather all device infos and ensure they are freed before returning
+	head := C.hid_enumerate(C.ushort(vendorID), C.ushort(productID))
+	if head == nil {
+		return nil
+	}
+	defer C.hid_free_enumeration(head)
+
+	// Iterate the list and retrieve the device details
+	var infos []DeviceInfo
+	for ; head != nil; head = head.next {
+		info := DeviceInfo{
+			Path:      C.GoString(head.path),
+			VendorID:  uint16(head.vendor_id),
+			ProductID: uint16(head.product_id),
+			Release:   uint16(head.release_number),
+			UsagePage: uint16(head.usage_page),
+			Usage:     uint16(head.usage),
+			Interface: int(head.interface_number),
+		}
+		if head.serial_number != nil {
+			info.Serial, _ = wcharTToString(head.serial_number)
+		}
+		if head.product_string != nil {
+			info.Product, _ = wcharTToString(head.product_string)
+		}
+		if head.manufacturer_string != nil {
+			info.Manufacturer, _ = wcharTToString(head.manufacturer_string)
+		}
+		infos = append(infos, info)
+	}
+	return infos
+}
+
+// Open connects to an HID device by its path name.
+func (info DeviceInfo) Open() (*Device, error) {
+	path := C.CString(info.Path)
+	defer C.free(unsafe.Pointer(path))
+
+	device := C.hid_open_path(path)
+	if device == nil {
+		return nil, errors.New("hidapi: failed to open device")
+	}
+	return &Device{
+		DeviceInfo: info,
+		device:     device,
+	}, nil
+}
+
+// Device is a live HID USB connected device handle.
+type Device struct {
+	DeviceInfo // Embed the infos for easier access
+
+	device *C.hid_device // Low level HID device to communicate through
+	lock   sync.Mutex
+}
+
+// Close releases the HID USB device handle.
+func (dev *Device) Close() {
+	dev.lock.Lock()
+	defer dev.lock.Unlock()
+
+	if dev.device != nil {
+		C.hid_close(dev.device)
+		dev.device = nil
+	}
+}
+
+// Write sends an output report to a HID device.
+//
+// Write will send the data on the first OUT endpoint, if one exists. If it does
+// not, it will send the data through the Control Endpoint (Endpoint 0).
+func (dev *Device) Write(b []byte) (int, error) {
+	// Abort if nothing to write
+	if len(b) == 0 {
+		return 0, nil
+	}
+	// Abort if device closed in between
+	dev.lock.Lock()
+	device := dev.device
+	dev.lock.Unlock()
+
+	if device == nil {
+		return 0, ErrDeviceClosed
+	}
+	// Prepend a HID report ID on Windows, other OSes don't need it
+	var report []byte
+	if runtime.GOOS == "windows" {
+		report = append([]byte{0x00}, b...)
+	} else {
+		report = b
+	}
+	// Execute the write operation
+	written := int(C.hid_write(device, (*C.uchar)(&report[0]), C.size_t(len(report))))
+	if written == -1 {
+		// If the write failed, verify if closed or other error
+		dev.lock.Lock()
+		device = dev.device
+		dev.lock.Unlock()
+
+		if device == nil {
+			return 0, ErrDeviceClosed
+		}
+		// Device not closed, some other error occurred
+		message := C.hid_error(device)
+		if message == nil {
+			return 0, errors.New("hidapi: unknown failure")
+		}
+		failure, _ := wcharTToString(message)
+		return 0, errors.New("hidapi: " + failure)
+	}
+	return written, nil
+}
+
+// Read retrieves an input report from a HID device.
+func (dev *Device) Read(b []byte) (int, error) {
+	// Aborth if nothing to read
+	if len(b) == 0 {
+		return 0, nil
+	}
+	// Abort if device closed in between
+	dev.lock.Lock()
+	device := dev.device
+	dev.lock.Unlock()
+
+	if device == nil {
+		return 0, ErrDeviceClosed
+	}
+	// Execute the read operation
+	read := int(C.hid_read(device, (*C.uchar)(&b[0]), C.size_t(len(b))))
+	if read == -1 {
+		// If the read failed, verify if closed or other error
+		dev.lock.Lock()
+		device = dev.device
+		dev.lock.Unlock()
+
+		if device == nil {
+			return 0, ErrDeviceClosed
+		}
+		// Device not closed, some other error occurred
+		message := C.hid_error(device)
+		if message == nil {
+			return 0, errors.New("hidapi: unknown failure")
+		}
+		failure, _ := wcharTToString(message)
+		return 0, errors.New("hidapi: " + failure)
+	}
+	return read, nil
+}
diff --git a/vendor/github.com/karalabe/hid/hidapi/AUTHORS.txt b/vendor/github.com/karalabe/hid/hidapi/AUTHORS.txt
new file mode 100644
index 000000000..7acafd78c
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/AUTHORS.txt
@@ -0,0 +1,16 @@
+
+HIDAPI Authors:
+
+Alan Ott <alan@signal11.us>:
+	Original Author and Maintainer
+	Linux, Windows, and Mac implementations
+
+Ludovic Rousseau <rousseau@debian.org>:
+	Formatting for Doxygen documentation
+	Bug fixes
+	Correctness fixes
+
+
+For a comprehensive list of contributions, see the commit list at github:
+	http://github.com/signal11/hidapi/commits/master
+
diff --git a/vendor/github.com/karalabe/hid/hidapi/LICENSE-bsd.txt b/vendor/github.com/karalabe/hid/hidapi/LICENSE-bsd.txt
new file mode 100644
index 000000000..538cdf95c
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/LICENSE-bsd.txt
@@ -0,0 +1,26 @@
+Copyright (c) 2010, Alan Ott, Signal 11 Software
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice,
+      this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+    * Neither the name of Signal 11 Software nor the names of its
+      contributors may be used to endorse or promote products derived from
+      this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/karalabe/hid/hidapi/LICENSE-gpl3.txt b/vendor/github.com/karalabe/hid/hidapi/LICENSE-gpl3.txt
new file mode 100644
index 000000000..94a9ed024
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/LICENSE-gpl3.txt
@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
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+
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+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
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+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
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+  14. Revised Versions of this License.
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+  Each version is given a distinguishing version number.  If the
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+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
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+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
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+to choose that version for the Program.
+
+  Later license versions may give you additional or different
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+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
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+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
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+  17. Interpretation of Sections 15 and 16.
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+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.
diff --git a/vendor/github.com/karalabe/hid/hidapi/LICENSE-orig.txt b/vendor/github.com/karalabe/hid/hidapi/LICENSE-orig.txt
new file mode 100644
index 000000000..e3f338082
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/LICENSE-orig.txt
@@ -0,0 +1,9 @@
+ HIDAPI - Multi-Platform library for
+ communication with HID devices.
+
+ Copyright 2009, Alan Ott, Signal 11 Software.
+ All Rights Reserved.
+ 
+ This software may be used by anyone for any reason so
+ long as the copyright notice in the source files
+ remains intact.
diff --git a/vendor/github.com/karalabe/hid/hidapi/LICENSE.txt b/vendor/github.com/karalabe/hid/hidapi/LICENSE.txt
new file mode 100644
index 000000000..e1676d4c4
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/LICENSE.txt
@@ -0,0 +1,13 @@
+HIDAPI can be used under one of three licenses.
+
+1. The GNU General Public License, version 3.0, in LICENSE-gpl3.txt
+2. A BSD-Style License, in LICENSE-bsd.txt.
+3. The more liberal original HIDAPI license. LICENSE-orig.txt
+
+The license chosen is at the discretion of the user of HIDAPI. For example:
+1. An author of GPL software would likely use HIDAPI under the terms of the
+GPL.
+
+2. An author of commercial closed-source software would likely use HIDAPI
+under the terms of the BSD-style license or the original HIDAPI license.
+
diff --git a/vendor/github.com/karalabe/hid/hidapi/README.txt b/vendor/github.com/karalabe/hid/hidapi/README.txt
new file mode 100644
index 000000000..f19dae4ab
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/README.txt
@@ -0,0 +1,339 @@
+         HIDAPI library for Windows, Linux, FreeBSD and Mac OS X
+        =========================================================
+
+About
+======
+
+HIDAPI is a multi-platform library which allows an application to interface
+with USB and Bluetooth HID-Class devices on Windows, Linux, FreeBSD, and Mac
+OS X.  HIDAPI can be either built as a shared library (.so or .dll) or
+can be embedded directly into a target application by adding a single source
+file (per platform) and a single header.
+
+HIDAPI has four back-ends:
+	* Windows (using hid.dll)
+	* Linux/hidraw (using the Kernel's hidraw driver)
+	* Linux/libusb (using libusb-1.0)
+	* FreeBSD (using libusb-1.0)
+	* Mac (using IOHidManager)
+
+On Linux, either the hidraw or the libusb back-end can be used. There are
+tradeoffs, and the functionality supported is slightly different.
+
+Linux/hidraw (linux/hid.c):
+This back-end uses the hidraw interface in the Linux kernel.  While this
+back-end will support both USB and Bluetooth, it has some limitations on
+kernels prior to 2.6.39, including the inability to send or receive feature
+reports.  In addition, it will only communicate with devices which have
+hidraw nodes associated with them.  Keyboards, mice, and some other devices
+which are blacklisted from having hidraw nodes will not work. Fortunately,
+for nearly all the uses of hidraw, this is not a problem.
+
+Linux/FreeBSD/libusb (libusb/hid.c):
+This back-end uses libusb-1.0 to communicate directly to a USB device. This
+back-end will of course not work with Bluetooth devices.
+
+HIDAPI also comes with a Test GUI. The Test GUI is cross-platform and uses
+Fox Toolkit (http://www.fox-toolkit.org).  It will build on every platform
+which HIDAPI supports.  Since it relies on a 3rd party library, building it
+is optional but recommended because it is so useful when debugging hardware.
+
+What Does the API Look Like?
+=============================
+The API provides the the most commonly used HID functions including sending
+and receiving of input, output, and feature reports.  The sample program,
+which communicates with a heavily hacked up version of the Microchip USB
+Generic HID sample looks like this (with error checking removed for
+simplicity):
+
+#ifdef WIN32
+#include <windows.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include "hidapi.h"
+
+#define MAX_STR 255
+
+int main(int argc, char* argv[])
+{
+	int res;
+	unsigned char buf[65];
+	wchar_t wstr[MAX_STR];
+	hid_device *handle;
+	int i;
+
+	// Initialize the hidapi library
+	res = hid_init();
+
+	// Open the device using the VID, PID,
+	// and optionally the Serial number.
+	handle = hid_open(0x4d8, 0x3f, NULL);
+
+	// Read the Manufacturer String
+	res = hid_get_manufacturer_string(handle, wstr, MAX_STR);
+	wprintf(L"Manufacturer String: %s\n", wstr);
+
+	// Read the Product String
+	res = hid_get_product_string(handle, wstr, MAX_STR);
+	wprintf(L"Product String: %s\n", wstr);
+
+	// Read the Serial Number String
+	res = hid_get_serial_number_string(handle, wstr, MAX_STR);
+	wprintf(L"Serial Number String: (%d) %s\n", wstr[0], wstr);
+
+	// Read Indexed String 1
+	res = hid_get_indexed_string(handle, 1, wstr, MAX_STR);
+	wprintf(L"Indexed String 1: %s\n", wstr);
+
+	// Toggle LED (cmd 0x80). The first byte is the report number (0x0).
+	buf[0] = 0x0;
+	buf[1] = 0x80;
+	res = hid_write(handle, buf, 65);
+
+	// Request state (cmd 0x81). The first byte is the report number (0x0).
+	buf[0] = 0x0;
+	buf[1] = 0x81;
+	res = hid_write(handle, buf, 65);
+
+	// Read requested state
+	res = hid_read(handle, buf, 65);
+
+	// Print out the returned buffer.
+	for (i = 0; i < 4; i++)
+		printf("buf[%d]: %d\n", i, buf[i]);
+
+	// Finalize the hidapi library
+	res = hid_exit();
+
+	return 0;
+}
+
+If you have your own simple test programs which communicate with standard
+hardware development boards (such as those from Microchip, TI, Atmel,
+FreeScale and others), please consider sending me something like the above
+for inclusion into the HIDAPI source.  This will help others who have the
+same hardware as you do.
+
+License
+========
+HIDAPI may be used by one of three licenses as outlined in LICENSE.txt.
+
+Download
+=========
+HIDAPI can be downloaded from github
+	git clone git://github.com/signal11/hidapi.git
+
+Build Instructions
+===================
+
+This section is long. Don't be put off by this. It's not long because it's
+complicated to build HIDAPI; it's quite the opposite.  This section is long
+because of the flexibility of HIDAPI and the large number of ways in which
+it can be built and used.  You will likely pick a single build method.
+
+HIDAPI can be built in several different ways. If you elect to build a
+shared library, you will need to build it from the HIDAPI source
+distribution.  If you choose instead to embed HIDAPI directly into your
+application, you can skip the building and look at the provided platform
+Makefiles for guidance.  These platform Makefiles are located in linux/
+libusb/ mac/ and windows/ and are called Makefile-manual.  In addition,
+Visual Studio projects are provided.  Even if you're going to embed HIDAPI
+into your project, it is still beneficial to build the example programs.
+
+
+Prerequisites:
+---------------
+
+	Linux:
+	-------
+	On Linux, you will need to install development packages for libudev,
+	libusb and optionally Fox-toolkit (for the test GUI). On
+	Debian/Ubuntu systems these can be installed by running:
+	    sudo apt-get install libudev-dev libusb-1.0-0-dev libfox-1.6-dev
+
+	If you downloaded the source directly from the git repository (using
+	git clone), you'll need Autotools:
+	    sudo apt-get install autotools-dev autoconf automake libtool
+
+	FreeBSD:
+	---------
+	On FreeBSD you will need to install GNU make, libiconv, and
+	optionally Fox-Toolkit (for the test GUI). This is done by running
+	the following:
+	    pkg_add -r gmake libiconv fox16
+
+	If you downloaded the source directly from the git repository (using
+	git clone), you'll need Autotools:
+	    pkg_add -r autotools
+
+	Mac:
+	-----
+	On Mac, you will need to install Fox-Toolkit if you wish to build
+	the Test GUI. There are two ways to do this, and each has a slight
+	complication. Which method you use depends on your use case.
+
+	If you wish to build the Test GUI just for your own testing on your
+	own computer, then the easiest method is to install Fox-Toolkit
+	using ports:
+		sudo port install fox
+
+	If you wish to build the TestGUI app bundle to redistribute to
+	others, you will need to install Fox-toolkit from source.  This is
+	because the version of fox that gets installed using ports uses the
+	ports X11 libraries which are not compatible with the Apple X11
+	libraries.  If you install Fox with ports and then try to distribute
+	your built app bundle, it will simply fail to run on other systems.
+	To install Fox-Toolkit manually, download the source package from
+	http://www.fox-toolkit.org, extract it, and run the following from
+	within the extracted source:
+		./configure && make && make install
+
+	Windows:
+	---------
+	On Windows, if you want to build the test GUI, you will need to get
+	the hidapi-externals.zip package from the download site.  This
+	contains pre-built binaries for Fox-toolkit.  Extract
+	hidapi-externals.zip just outside of hidapi, so that
+	hidapi-externals and hidapi are on the same level, as shown:
+
+	     Parent_Folder
+	       |
+	       +hidapi
+	       +hidapi-externals
+
+	Again, this step is not required if you do not wish to build the
+	test GUI.
+
+
+Building HIDAPI into a shared library on Unix Platforms:
+---------------------------------------------------------
+
+On Unix-like systems such as Linux, FreeBSD, Mac, and even Windows, using
+Mingw or Cygwin, the easiest way to build a standard system-installed shared
+library is to use the GNU Autotools build system.  If you checked out the
+source from the git repository, run the following:
+
+	./bootstrap
+	./configure
+	make
+	make install     <----- as root, or using sudo
+
+If you downloaded a source package (ie: if you did not run git clone), you
+can skip the ./bootstrap step.
+
+./configure can take several arguments which control the build. The two most
+likely to be used are:
+	--enable-testgui
+		Enable build of the Test GUI. This requires Fox toolkit to
+		be installed.  Instructions for installing Fox-Toolkit on
+		each platform are in the Prerequisites section above.
+
+	--prefix=/usr
+		Specify where you want the output headers and libraries to
+		be installed. The example above will put the headers in
+		/usr/include and the binaries in /usr/lib. The default is to
+		install into /usr/local which is fine on most systems.
+
+Building the manual way on Unix platforms:
+-------------------------------------------
+
+Manual Makefiles are provided mostly to give the user and idea what it takes
+to build a program which embeds HIDAPI directly inside of it. These should
+really be used as examples only. If you want to build a system-wide shared
+library, use the Autotools method described above.
+
+	To build HIDAPI using the manual makefiles, change to the directory
+	of your platform and run make. For example, on Linux run:
+		cd linux/
+		make -f Makefile-manual
+
+	To build the Test GUI using the manual makefiles:
+		cd testgui/
+		make -f Makefile-manual
+
+Building on Windows:
+---------------------
+
+To build the HIDAPI DLL on Windows using Visual Studio, build the .sln file
+in the windows/ directory.
+
+To build the Test GUI on windows using Visual Studio, build the .sln file in
+the testgui/ directory.
+
+To build HIDAPI using MinGW or Cygwin using Autotools, use the instructions
+in the section titled "Building HIDAPI into a shared library on Unix
+Platforms" above.  Note that building the Test GUI with MinGW or Cygwin will
+require the Windows procedure in the Prerequisites section above (ie:
+hidapi-externals.zip).
+
+To build HIDAPI using MinGW using the Manual Makefiles, see the section
+"Building the manual way on Unix platforms" above.
+
+HIDAPI can also be built using the Windows DDK (now also called the Windows
+Driver Kit or WDK). This method was originally required for the HIDAPI build
+but not anymore. However, some users still prefer this method. It is not as
+well supported anymore but should still work. Patches are welcome if it does
+not. To build using the DDK:
+
+   1. Install the Windows Driver Kit (WDK) from Microsoft.
+   2. From the Start menu, in the Windows Driver Kits folder, select Build
+      Environments, then your operating system, then the x86 Free Build
+      Environment (or one that is appropriate for your system).
+   3. From the console, change directory to the windows/ddk_build/ directory,
+      which is part of the HIDAPI distribution.
+   4. Type build.
+   5. You can find the output files (DLL and LIB) in a subdirectory created
+      by the build system which is appropriate for your environment. On
+      Windows XP, this directory is objfre_wxp_x86/i386.
+
+Cross Compiling
+================
+
+This section talks about cross compiling HIDAPI for Linux using autotools.
+This is useful for using HIDAPI on embedded Linux targets.  These
+instructions assume the most raw kind of embedded Linux build, where all
+prerequisites will need to be built first.  This process will of course vary
+based on your embedded Linux build system if you are using one, such as
+OpenEmbedded or Buildroot.
+
+For the purpose of this section, it will be assumed that the following
+environment variables are exported.
+
+	$ export STAGING=$HOME/out
+	$ export HOST=arm-linux
+
+STAGING and HOST can be modified to suit your setup.
+
+Prerequisites
+--------------
+
+Note that the build of libudev is the very basic configuration.
+
+Build Libusb. From the libusb source directory, run:
+	./configure --host=$HOST --prefix=$STAGING
+	make
+	make install
+
+Build libudev. From the libudev source directory, run:
+	./configure --disable-gudev --disable-introspection --disable-hwdb \
+		 --host=$HOST --prefix=$STAGING
+	make
+	make install
+
+Building HIDAPI
+----------------
+
+Build HIDAPI:
+
+	PKG_CONFIG_DIR= \
+	PKG_CONFIG_LIBDIR=$STAGING/lib/pkgconfig:$STAGING/share/pkgconfig \
+	PKG_CONFIG_SYSROOT_DIR=$STAGING \
+	./configure --host=$HOST --prefix=$STAGING
+
+
+Signal 11 Software - 2010-04-11
+                     2010-07-28
+                     2011-09-10
+                     2012-05-01
+                     2012-07-03
diff --git a/vendor/github.com/karalabe/hid/hidapi/hidapi/hidapi.h b/vendor/github.com/karalabe/hid/hidapi/hidapi/hidapi.h
new file mode 100644
index 000000000..e5bc2dc40
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/hidapi/hidapi.h
@@ -0,0 +1,391 @@
+/*******************************************************
+ HIDAPI - Multi-Platform library for
+ communication with HID devices.
+
+ Alan Ott
+ Signal 11 Software
+
+ 8/22/2009
+
+ Copyright 2009, All Rights Reserved.
+
+ At the discretion of the user of this library,
+ this software may be licensed under the terms of the
+ GNU General Public License v3, a BSD-Style license, or the
+ original HIDAPI license as outlined in the LICENSE.txt,
+ LICENSE-gpl3.txt, LICENSE-bsd.txt, and LICENSE-orig.txt
+ files located at the root of the source distribution.
+ These files may also be found in the public source
+ code repository located at:
+        http://github.com/signal11/hidapi .
+********************************************************/
+
+/** @file
+ * @defgroup API hidapi API
+ */
+
+#ifndef HIDAPI_H__
+#define HIDAPI_H__
+
+#include <wchar.h>
+
+#ifdef _WIN32
+      #define HID_API_EXPORT __declspec(dllexport)
+      #define HID_API_CALL
+#else
+      #define HID_API_EXPORT /**< API export macro */
+      #define HID_API_CALL /**< API call macro */
+#endif
+
+#define HID_API_EXPORT_CALL HID_API_EXPORT HID_API_CALL /**< API export and call macro*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+		struct hid_device_;
+		typedef struct hid_device_ hid_device; /**< opaque hidapi structure */
+
+		/** hidapi info structure */
+		struct hid_device_info {
+			/** Platform-specific device path */
+			char *path;
+			/** Device Vendor ID */
+			unsigned short vendor_id;
+			/** Device Product ID */
+			unsigned short product_id;
+			/** Serial Number */
+			wchar_t *serial_number;
+			/** Device Release Number in binary-coded decimal,
+			    also known as Device Version Number */
+			unsigned short release_number;
+			/** Manufacturer String */
+			wchar_t *manufacturer_string;
+			/** Product string */
+			wchar_t *product_string;
+			/** Usage Page for this Device/Interface
+			    (Windows/Mac only). */
+			unsigned short usage_page;
+			/** Usage for this Device/Interface
+			    (Windows/Mac only).*/
+			unsigned short usage;
+			/** The USB interface which this logical device
+			    represents. Valid on both Linux implementations
+			    in all cases, and valid on the Windows implementation
+			    only if the device contains more than one interface. */
+			int interface_number;
+
+			/** Pointer to the next device */
+			struct hid_device_info *next;
+		};
+
+
+		/** @brief Initialize the HIDAPI library.
+
+			This function initializes the HIDAPI library. Calling it is not
+			strictly necessary, as it will be called automatically by
+			hid_enumerate() and any of the hid_open_*() functions if it is
+			needed.  This function should be called at the beginning of
+			execution however, if there is a chance of HIDAPI handles
+			being opened by different threads simultaneously.
+			
+			@ingroup API
+
+			@returns
+				This function returns 0 on success and -1 on error.
+		*/
+		int HID_API_EXPORT HID_API_CALL hid_init(void);
+
+		/** @brief Finalize the HIDAPI library.
+
+			This function frees all of the static data associated with
+			HIDAPI. It should be called at the end of execution to avoid
+			memory leaks.
+
+			@ingroup API
+
+		    @returns
+				This function returns 0 on success and -1 on error.
+		*/
+		int HID_API_EXPORT HID_API_CALL hid_exit(void);
+
+		/** @brief Enumerate the HID Devices.
+
+			This function returns a linked list of all the HID devices
+			attached to the system which match vendor_id and product_id.
+			If @p vendor_id is set to 0 then any vendor matches.
+			If @p product_id is set to 0 then any product matches.
+			If @p vendor_id and @p product_id are both set to 0, then
+			all HID devices will be returned.
+
+			@ingroup API
+			@param vendor_id The Vendor ID (VID) of the types of device
+				to open.
+			@param product_id The Product ID (PID) of the types of
+				device to open.
+
+		    @returns
+		    	This function returns a pointer to a linked list of type
+		    	struct #hid_device, containing information about the HID devices
+		    	attached to the system, or NULL in the case of failure. Free
+		    	this linked list by calling hid_free_enumeration().
+		*/
+		struct hid_device_info HID_API_EXPORT * HID_API_CALL hid_enumerate(unsigned short vendor_id, unsigned short product_id);
+
+		/** @brief Free an enumeration Linked List
+
+		    This function frees a linked list created by hid_enumerate().
+
+			@ingroup API
+		    @param devs Pointer to a list of struct_device returned from
+		    	      hid_enumerate().
+		*/
+		void  HID_API_EXPORT HID_API_CALL hid_free_enumeration(struct hid_device_info *devs);
+
+		/** @brief Open a HID device using a Vendor ID (VID), Product ID
+			(PID) and optionally a serial number.
+
+			If @p serial_number is NULL, the first device with the
+			specified VID and PID is opened.
+
+			@ingroup API
+			@param vendor_id The Vendor ID (VID) of the device to open.
+			@param product_id The Product ID (PID) of the device to open.
+			@param serial_number The Serial Number of the device to open
+				               (Optionally NULL).
+
+			@returns
+				This function returns a pointer to a #hid_device object on
+				success or NULL on failure.
+		*/
+		HID_API_EXPORT hid_device * HID_API_CALL hid_open(unsigned short vendor_id, unsigned short product_id, const wchar_t *serial_number);
+
+		/** @brief Open a HID device by its path name.
+
+			The path name be determined by calling hid_enumerate(), or a
+			platform-specific path name can be used (eg: /dev/hidraw0 on
+			Linux).
+
+			@ingroup API
+		    @param path The path name of the device to open
+
+			@returns
+				This function returns a pointer to a #hid_device object on
+				success or NULL on failure.
+		*/
+		HID_API_EXPORT hid_device * HID_API_CALL hid_open_path(const char *path);
+
+		/** @brief Write an Output report to a HID device.
+
+			The first byte of @p data[] must contain the Report ID. For
+			devices which only support a single report, this must be set
+			to 0x0. The remaining bytes contain the report data. Since
+			the Report ID is mandatory, calls to hid_write() will always
+			contain one more byte than the report contains. For example,
+			if a hid report is 16 bytes long, 17 bytes must be passed to
+			hid_write(), the Report ID (or 0x0, for devices with a
+			single report), followed by the report data (16 bytes). In
+			this example, the length passed in would be 17.
+
+			hid_write() will send the data on the first OUT endpoint, if
+			one exists. If it does not, it will send the data through
+			the Control Endpoint (Endpoint 0).
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param data The data to send, including the report number as
+				the first byte.
+			@param length The length in bytes of the data to send.
+
+			@returns
+				This function returns the actual number of bytes written and
+				-1 on error.
+		*/
+		int  HID_API_EXPORT HID_API_CALL hid_write(hid_device *device, const unsigned char *data, size_t length);
+
+		/** @brief Read an Input report from a HID device with timeout.
+
+			Input reports are returned
+			to the host through the INTERRUPT IN endpoint. The first byte will
+			contain the Report number if the device uses numbered reports.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param data A buffer to put the read data into.
+			@param length The number of bytes to read. For devices with
+				multiple reports, make sure to read an extra byte for
+				the report number.
+			@param milliseconds timeout in milliseconds or -1 for blocking wait.
+
+			@returns
+				This function returns the actual number of bytes read and
+				-1 on error. If no packet was available to be read within
+				the timeout period, this function returns 0.
+		*/
+		int HID_API_EXPORT HID_API_CALL hid_read_timeout(hid_device *dev, unsigned char *data, size_t length, int milliseconds);
+
+		/** @brief Read an Input report from a HID device.
+
+			Input reports are returned
+		    to the host through the INTERRUPT IN endpoint. The first byte will
+			contain the Report number if the device uses numbered reports.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param data A buffer to put the read data into.
+			@param length The number of bytes to read. For devices with
+				multiple reports, make sure to read an extra byte for
+				the report number.
+
+			@returns
+				This function returns the actual number of bytes read and
+				-1 on error. If no packet was available to be read and
+				the handle is in non-blocking mode, this function returns 0.
+		*/
+		int  HID_API_EXPORT HID_API_CALL hid_read(hid_device *device, unsigned char *data, size_t length);
+
+		/** @brief Set the device handle to be non-blocking.
+
+			In non-blocking mode calls to hid_read() will return
+			immediately with a value of 0 if there is no data to be
+			read. In blocking mode, hid_read() will wait (block) until
+			there is data to read before returning.
+
+			Nonblocking can be turned on and off at any time.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param nonblock enable or not the nonblocking reads
+			 - 1 to enable nonblocking
+			 - 0 to disable nonblocking.
+
+			@returns
+				This function returns 0 on success and -1 on error.
+		*/
+		int  HID_API_EXPORT HID_API_CALL hid_set_nonblocking(hid_device *device, int nonblock);
+
+		/** @brief Send a Feature report to the device.
+
+			Feature reports are sent over the Control endpoint as a
+			Set_Report transfer.  The first byte of @p data[] must
+			contain the Report ID. For devices which only support a
+			single report, this must be set to 0x0. The remaining bytes
+			contain the report data. Since the Report ID is mandatory,
+			calls to hid_send_feature_report() will always contain one
+			more byte than the report contains. For example, if a hid
+			report is 16 bytes long, 17 bytes must be passed to
+			hid_send_feature_report(): the Report ID (or 0x0, for
+			devices which do not use numbered reports), followed by the
+			report data (16 bytes). In this example, the length passed
+			in would be 17.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param data The data to send, including the report number as
+				the first byte.
+			@param length The length in bytes of the data to send, including
+				the report number.
+
+			@returns
+				This function returns the actual number of bytes written and
+				-1 on error.
+		*/
+		int HID_API_EXPORT HID_API_CALL hid_send_feature_report(hid_device *device, const unsigned char *data, size_t length);
+
+		/** @brief Get a feature report from a HID device.
+
+			Set the first byte of @p data[] to the Report ID of the
+			report to be read.  Make sure to allow space for this
+			extra byte in @p data[]. Upon return, the first byte will
+			still contain the Report ID, and the report data will
+			start in data[1].
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param data A buffer to put the read data into, including
+				the Report ID. Set the first byte of @p data[] to the
+				Report ID of the report to be read, or set it to zero
+				if your device does not use numbered reports.
+			@param length The number of bytes to read, including an
+				extra byte for the report ID. The buffer can be longer
+				than the actual report.
+
+			@returns
+				This function returns the number of bytes read plus
+				one for the report ID (which is still in the first
+				byte), or -1 on error.
+		*/
+		int HID_API_EXPORT HID_API_CALL hid_get_feature_report(hid_device *device, unsigned char *data, size_t length);
+
+		/** @brief Close a HID device.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+		*/
+		void HID_API_EXPORT HID_API_CALL hid_close(hid_device *device);
+
+		/** @brief Get The Manufacturer String from a HID device.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param string A wide string buffer to put the data into.
+			@param maxlen The length of the buffer in multiples of wchar_t.
+
+			@returns
+				This function returns 0 on success and -1 on error.
+		*/
+		int HID_API_EXPORT_CALL hid_get_manufacturer_string(hid_device *device, wchar_t *string, size_t maxlen);
+
+		/** @brief Get The Product String from a HID device.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param string A wide string buffer to put the data into.
+			@param maxlen The length of the buffer in multiples of wchar_t.
+
+			@returns
+				This function returns 0 on success and -1 on error.
+		*/
+		int HID_API_EXPORT_CALL hid_get_product_string(hid_device *device, wchar_t *string, size_t maxlen);
+
+		/** @brief Get The Serial Number String from a HID device.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param string A wide string buffer to put the data into.
+			@param maxlen The length of the buffer in multiples of wchar_t.
+
+			@returns
+				This function returns 0 on success and -1 on error.
+		*/
+		int HID_API_EXPORT_CALL hid_get_serial_number_string(hid_device *device, wchar_t *string, size_t maxlen);
+
+		/** @brief Get a string from a HID device, based on its string index.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+			@param string_index The index of the string to get.
+			@param string A wide string buffer to put the data into.
+			@param maxlen The length of the buffer in multiples of wchar_t.
+
+			@returns
+				This function returns 0 on success and -1 on error.
+		*/
+		int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *device, int string_index, wchar_t *string, size_t maxlen);
+
+		/** @brief Get a string describing the last error which occurred.
+
+			@ingroup API
+			@param device A device handle returned from hid_open().
+
+			@returns
+				This function returns a string containing the last error
+				which occurred or NULL if none has occurred.
+		*/
+		HID_API_EXPORT const wchar_t* HID_API_CALL hid_error(hid_device *device);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
+
diff --git a/vendor/github.com/karalabe/hid/hidapi/libusb/hid.c b/vendor/github.com/karalabe/hid/hidapi/libusb/hid.c
new file mode 100644
index 000000000..474dff41c
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/libusb/hid.c
@@ -0,0 +1,1512 @@
+/*******************************************************
+ HIDAPI - Multi-Platform library for
+ communication with HID devices.
+
+ Alan Ott
+ Signal 11 Software
+
+ 8/22/2009
+ Linux Version - 6/2/2010
+ Libusb Version - 8/13/2010
+ FreeBSD Version - 11/1/2011
+
+ Copyright 2009, All Rights Reserved.
+
+ At the discretion of the user of this library,
+ this software may be licensed under the terms of the
+ GNU General Public License v3, a BSD-Style license, or the
+ original HIDAPI license as outlined in the LICENSE.txt,
+ LICENSE-gpl3.txt, LICENSE-bsd.txt, and LICENSE-orig.txt
+ files located at the root of the source distribution.
+ These files may also be found in the public source
+ code repository located at:
+        http://github.com/signal11/hidapi .
+********************************************************/
+
+/* C */
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <locale.h>
+#include <errno.h>
+
+/* Unix */
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/utsname.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <wchar.h>
+
+/* GNU / LibUSB */
+#include <libusb.h>
+#ifndef __ANDROID__
+#include <iconv.h>
+#endif
+
+#include "hidapi.h"
+
+#ifdef __ANDROID__
+
+/* Barrier implementation because Android/Bionic don't have pthread_barrier.
+   This implementation came from Brent Priddy and was posted on
+   StackOverflow. It is used with his permission. */
+typedef int pthread_barrierattr_t;
+typedef struct pthread_barrier {
+    pthread_mutex_t mutex;
+    pthread_cond_t cond;
+    int count;
+    int trip_count;
+} pthread_barrier_t;
+
+static int pthread_barrier_init(pthread_barrier_t *barrier, const pthread_barrierattr_t *attr, unsigned int count)
+{
+	if(count == 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if(pthread_mutex_init(&barrier->mutex, 0) < 0) {
+		return -1;
+	}
+	if(pthread_cond_init(&barrier->cond, 0) < 0) {
+		pthread_mutex_destroy(&barrier->mutex);
+		return -1;
+	}
+	barrier->trip_count = count;
+	barrier->count = 0;
+
+	return 0;
+}
+
+static int pthread_barrier_destroy(pthread_barrier_t *barrier)
+{
+	pthread_cond_destroy(&barrier->cond);
+	pthread_mutex_destroy(&barrier->mutex);
+	return 0;
+}
+
+static int pthread_barrier_wait(pthread_barrier_t *barrier)
+{
+	pthread_mutex_lock(&barrier->mutex);
+	++(barrier->count);
+	if(barrier->count >= barrier->trip_count)
+	{
+		barrier->count = 0;
+		pthread_cond_broadcast(&barrier->cond);
+		pthread_mutex_unlock(&barrier->mutex);
+		return 1;
+	}
+	else
+	{
+		pthread_cond_wait(&barrier->cond, &(barrier->mutex));
+		pthread_mutex_unlock(&barrier->mutex);
+		return 0;
+	}
+}
+
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef DEBUG_PRINTF
+#define LOG(...) fprintf(stderr, __VA_ARGS__)
+#else
+#define LOG(...) do {} while (0)
+#endif
+
+#ifndef __FreeBSD__
+#define DETACH_KERNEL_DRIVER
+#endif
+
+/* Uncomment to enable the retrieval of Usage and Usage Page in
+hid_enumerate(). Warning, on platforms different from FreeBSD
+this is very invasive as it requires the detach
+and re-attach of the kernel driver. See comments inside hid_enumerate().
+libusb HIDAPI programs are encouraged to use the interface number
+instead to differentiate between interfaces on a composite HID device. */
+/*#define INVASIVE_GET_USAGE*/
+
+/* Linked List of input reports received from the device. */
+struct input_report {
+	uint8_t *data;
+	size_t len;
+	struct input_report *next;
+};
+
+
+struct hid_device_ {
+	/* Handle to the actual device. */
+	libusb_device_handle *device_handle;
+
+	/* Endpoint information */
+	int input_endpoint;
+	int output_endpoint;
+	int input_ep_max_packet_size;
+
+	/* The interface number of the HID */
+	int interface;
+
+	/* Indexes of Strings */
+	int manufacturer_index;
+	int product_index;
+	int serial_index;
+
+	/* Whether blocking reads are used */
+	int blocking; /* boolean */
+
+	/* Read thread objects */
+	pthread_t thread;
+	pthread_mutex_t mutex; /* Protects input_reports */
+	pthread_cond_t condition;
+	pthread_barrier_t barrier; /* Ensures correct startup sequence */
+	int shutdown_thread;
+	int cancelled;
+	struct libusb_transfer *transfer;
+
+	/* List of received input reports. */
+	struct input_report *input_reports;
+};
+
+static libusb_context *usb_context = NULL;
+
+uint16_t get_usb_code_for_current_locale(void);
+static int return_data(hid_device *dev, unsigned char *data, size_t length);
+
+static hid_device *new_hid_device(void)
+{
+	hid_device *dev = calloc(1, sizeof(hid_device));
+	dev->blocking = 1;
+
+	pthread_mutex_init(&dev->mutex, NULL);
+	pthread_cond_init(&dev->condition, NULL);
+	pthread_barrier_init(&dev->barrier, NULL, 2);
+
+	return dev;
+}
+
+static void free_hid_device(hid_device *dev)
+{
+	/* Clean up the thread objects */
+	pthread_barrier_destroy(&dev->barrier);
+	pthread_cond_destroy(&dev->condition);
+	pthread_mutex_destroy(&dev->mutex);
+
+	/* Free the device itself */
+	free(dev);
+}
+
+#if 0
+/*TODO: Implement this funciton on hidapi/libusb.. */
+static void register_error(hid_device *device, const char *op)
+{
+
+}
+#endif
+
+#ifdef INVASIVE_GET_USAGE
+/* Get bytes from a HID Report Descriptor.
+   Only call with a num_bytes of 0, 1, 2, or 4. */
+static uint32_t get_bytes(uint8_t *rpt, size_t len, size_t num_bytes, size_t cur)
+{
+	/* Return if there aren't enough bytes. */
+	if (cur + num_bytes >= len)
+		return 0;
+
+	if (num_bytes == 0)
+		return 0;
+	else if (num_bytes == 1) {
+		return rpt[cur+1];
+	}
+	else if (num_bytes == 2) {
+		return (rpt[cur+2] * 256 + rpt[cur+1]);
+	}
+	else if (num_bytes == 4) {
+		return (rpt[cur+4] * 0x01000000 +
+		        rpt[cur+3] * 0x00010000 +
+		        rpt[cur+2] * 0x00000100 +
+		        rpt[cur+1] * 0x00000001);
+	}
+	else
+		return 0;
+}
+
+/* Retrieves the device's Usage Page and Usage from the report
+   descriptor. The algorithm is simple, as it just returns the first
+   Usage and Usage Page that it finds in the descriptor.
+   The return value is 0 on success and -1 on failure. */
+static int get_usage(uint8_t *report_descriptor, size_t size,
+                     unsigned short *usage_page, unsigned short *usage)
+{
+	unsigned int i = 0;
+	int size_code;
+	int data_len, key_size;
+	int usage_found = 0, usage_page_found = 0;
+
+	while (i < size) {
+		int key = report_descriptor[i];
+		int key_cmd = key & 0xfc;
+
+		//printf("key: %02hhx\n", key);
+
+		if ((key & 0xf0) == 0xf0) {
+			/* This is a Long Item. The next byte contains the
+			   length of the data section (value) for this key.
+			   See the HID specification, version 1.11, section
+			   6.2.2.3, titled "Long Items." */
+			if (i+1 < size)
+				data_len = report_descriptor[i+1];
+			else
+				data_len = 0; /* malformed report */
+			key_size = 3;
+		}
+		else {
+			/* This is a Short Item. The bottom two bits of the
+			   key contain the size code for the data section
+			   (value) for this key.  Refer to the HID
+			   specification, version 1.11, section 6.2.2.2,
+			   titled "Short Items." */
+			size_code = key & 0x3;
+			switch (size_code) {
+			case 0:
+			case 1:
+			case 2:
+				data_len = size_code;
+				break;
+			case 3:
+				data_len = 4;
+				break;
+			default:
+				/* Can't ever happen since size_code is & 0x3 */
+				data_len = 0;
+				break;
+			};
+			key_size = 1;
+		}
+
+		if (key_cmd == 0x4) {
+			*usage_page  = get_bytes(report_descriptor, size, data_len, i);
+			usage_page_found = 1;
+			//printf("Usage Page: %x\n", (uint32_t)*usage_page);
+		}
+		if (key_cmd == 0x8) {
+			*usage = get_bytes(report_descriptor, size, data_len, i);
+			usage_found = 1;
+			//printf("Usage: %x\n", (uint32_t)*usage);
+		}
+
+		if (usage_page_found && usage_found)
+			return 0; /* success */
+
+		/* Skip over this key and it's associated data */
+		i += data_len + key_size;
+	}
+
+	return -1; /* failure */
+}
+#endif /* INVASIVE_GET_USAGE */
+
+#if defined(__FreeBSD__) && __FreeBSD__ < 10
+/* The libusb version included in FreeBSD < 10 doesn't have this function. In
+   mainline libusb, it's inlined in libusb.h. This function will bear a striking
+   resemblance to that one, because there's about one way to code it.
+
+   Note that the data parameter is Unicode in UTF-16LE encoding.
+   Return value is the number of bytes in data, or LIBUSB_ERROR_*.
+ */
+static inline int libusb_get_string_descriptor(libusb_device_handle *dev,
+	uint8_t descriptor_index, uint16_t lang_id,
+	unsigned char *data, int length)
+{
+	return libusb_control_transfer(dev,
+		LIBUSB_ENDPOINT_IN | 0x0, /* Endpoint 0 IN */
+		LIBUSB_REQUEST_GET_DESCRIPTOR,
+		(LIBUSB_DT_STRING << 8) | descriptor_index,
+		lang_id, data, (uint16_t) length, 1000);
+}
+
+#endif
+
+
+/* Get the first language the device says it reports. This comes from
+   USB string #0. */
+static uint16_t get_first_language(libusb_device_handle *dev)
+{
+	uint16_t buf[32];
+	int len;
+
+	/* Get the string from libusb. */
+	len = libusb_get_string_descriptor(dev,
+			0x0, /* String ID */
+			0x0, /* Language */
+			(unsigned char*)buf,
+			sizeof(buf));
+	if (len < 4)
+		return 0x0;
+
+	return buf[1]; /* First two bytes are len and descriptor type. */
+}
+
+static int is_language_supported(libusb_device_handle *dev, uint16_t lang)
+{
+	uint16_t buf[32];
+	int len;
+	int i;
+
+	/* Get the string from libusb. */
+	len = libusb_get_string_descriptor(dev,
+			0x0, /* String ID */
+			0x0, /* Language */
+			(unsigned char*)buf,
+			sizeof(buf));
+	if (len < 4)
+		return 0x0;
+
+
+	len /= 2; /* language IDs are two-bytes each. */
+	/* Start at index 1 because there are two bytes of protocol data. */
+	for (i = 1; i < len; i++) {
+		if (buf[i] == lang)
+			return 1;
+	}
+
+	return 0;
+}
+
+
+/* This function returns a newly allocated wide string containing the USB
+   device string numbered by the index. The returned string must be freed
+   by using free(). */
+static wchar_t *get_usb_string(libusb_device_handle *dev, uint8_t idx)
+{
+	char buf[512];
+	int len;
+	wchar_t *str = NULL;
+
+#ifndef __ANDROID__ /* we don't use iconv on Android */
+	wchar_t wbuf[256];
+	/* iconv variables */
+	iconv_t ic;
+	size_t inbytes;
+	size_t outbytes;
+	size_t res;
+#ifdef __FreeBSD__
+	const char *inptr;
+#else
+	char *inptr;
+#endif
+	char *outptr;
+#endif
+
+	/* Determine which language to use. */
+	uint16_t lang;
+	lang = get_usb_code_for_current_locale();
+	if (!is_language_supported(dev, lang))
+		lang = get_first_language(dev);
+
+	/* Get the string from libusb. */
+	len = libusb_get_string_descriptor(dev,
+			idx,
+			lang,
+			(unsigned char*)buf,
+			sizeof(buf));
+	if (len < 0)
+		return NULL;
+
+#ifdef __ANDROID__
+
+	/* Bionic does not have iconv support nor wcsdup() function, so it
+	   has to be done manually.  The following code will only work for
+	   code points that can be represented as a single UTF-16 character,
+	   and will incorrectly convert any code points which require more
+	   than one UTF-16 character.
+
+	   Skip over the first character (2-bytes).  */
+	len -= 2;
+	str = malloc((len / 2 + 1) * sizeof(wchar_t));
+	int i;
+	for (i = 0; i < len / 2; i++) {
+		str[i] = buf[i * 2 + 2] | (buf[i * 2 + 3] << 8);
+	}
+	str[len / 2] = 0x00000000;
+
+#else
+
+	/* buf does not need to be explicitly NULL-terminated because
+	   it is only passed into iconv() which does not need it. */
+
+	/* Initialize iconv. */
+	ic = iconv_open("WCHAR_T", "UTF-16LE");
+	if (ic == (iconv_t)-1) {
+		LOG("iconv_open() failed\n");
+		return NULL;
+	}
+
+	/* Convert to native wchar_t (UTF-32 on glibc/BSD systems).
+	   Skip the first character (2-bytes). */
+	inptr = buf+2;
+	inbytes = len-2;
+	outptr = (char*) wbuf;
+	outbytes = sizeof(wbuf);
+	res = iconv(ic, &inptr, &inbytes, &outptr, &outbytes);
+	if (res == (size_t)-1) {
+		LOG("iconv() failed\n");
+		goto err;
+	}
+
+	/* Write the terminating NULL. */
+	wbuf[sizeof(wbuf)/sizeof(wbuf[0])-1] = 0x00000000;
+	if (outbytes >= sizeof(wbuf[0]))
+		*((wchar_t*)outptr) = 0x00000000;
+
+	/* Allocate and copy the string. */
+	str = wcsdup(wbuf);
+
+err:
+	iconv_close(ic);
+
+#endif
+
+	return str;
+}
+
+static char *make_path(libusb_device *dev, int interface_number)
+{
+	char str[64];
+	snprintf(str, sizeof(str), "%04x:%04x:%02x",
+		libusb_get_bus_number(dev),
+		libusb_get_device_address(dev),
+		interface_number);
+	str[sizeof(str)-1] = '\0';
+
+	return strdup(str);
+}
+
+
+int HID_API_EXPORT hid_init(void)
+{
+	if (!usb_context) {
+		const char *locale;
+
+		/* Init Libusb */
+		if (libusb_init(&usb_context))
+			return -1;
+
+		/* Set the locale if it's not set. */
+		locale = setlocale(LC_CTYPE, NULL);
+		if (!locale)
+			setlocale(LC_CTYPE, "");
+	}
+
+	return 0;
+}
+
+int HID_API_EXPORT hid_exit(void)
+{
+	if (usb_context) {
+		libusb_exit(usb_context);
+		usb_context = NULL;
+	}
+
+	return 0;
+}
+
+struct hid_device_info  HID_API_EXPORT *hid_enumerate(unsigned short vendor_id, unsigned short product_id)
+{
+	libusb_device **devs;
+	libusb_device *dev;
+	libusb_device_handle *handle;
+	ssize_t num_devs;
+	int i = 0;
+
+	struct hid_device_info *root = NULL; /* return object */
+	struct hid_device_info *cur_dev = NULL;
+
+	if(hid_init() < 0)
+		return NULL;
+
+	num_devs = libusb_get_device_list(usb_context, &devs);
+	if (num_devs < 0)
+		return NULL;
+	while ((dev = devs[i++]) != NULL) {
+		struct libusb_device_descriptor desc;
+		struct libusb_config_descriptor *conf_desc = NULL;
+		int j, k;
+		int interface_num = 0;
+
+		int res = libusb_get_device_descriptor(dev, &desc);
+		unsigned short dev_vid = desc.idVendor;
+		unsigned short dev_pid = desc.idProduct;
+
+		res = libusb_get_active_config_descriptor(dev, &conf_desc);
+		if (res < 0)
+			libusb_get_config_descriptor(dev, 0, &conf_desc);
+		if (conf_desc) {
+			for (j = 0; j < conf_desc->bNumInterfaces; j++) {
+				const struct libusb_interface *intf = &conf_desc->interface[j];
+				for (k = 0; k < intf->num_altsetting; k++) {
+					const struct libusb_interface_descriptor *intf_desc;
+					intf_desc = &intf->altsetting[k];
+					if (intf_desc->bInterfaceClass == LIBUSB_CLASS_HID) {
+						interface_num = intf_desc->bInterfaceNumber;
+
+						/* Check the VID/PID against the arguments */
+						if ((vendor_id == 0x0 || vendor_id == dev_vid) &&
+						    (product_id == 0x0 || product_id == dev_pid)) {
+							struct hid_device_info *tmp;
+
+							/* VID/PID match. Create the record. */
+							tmp = calloc(1, sizeof(struct hid_device_info));
+							if (cur_dev) {
+								cur_dev->next = tmp;
+							}
+							else {
+								root = tmp;
+							}
+							cur_dev = tmp;
+
+							/* Fill out the record */
+							cur_dev->next = NULL;
+							cur_dev->path = make_path(dev, interface_num);
+
+							res = libusb_open(dev, &handle);
+
+							if (res >= 0) {
+								/* Serial Number */
+								if (desc.iSerialNumber > 0)
+									cur_dev->serial_number =
+										get_usb_string(handle, desc.iSerialNumber);
+
+								/* Manufacturer and Product strings */
+								if (desc.iManufacturer > 0)
+									cur_dev->manufacturer_string =
+										get_usb_string(handle, desc.iManufacturer);
+								if (desc.iProduct > 0)
+									cur_dev->product_string =
+										get_usb_string(handle, desc.iProduct);
+
+#ifdef INVASIVE_GET_USAGE
+{
+							/*
+							This section is removed because it is too
+							invasive on the system. Getting a Usage Page
+							and Usage requires parsing the HID Report
+							descriptor. Getting a HID Report descriptor
+							involves claiming the interface. Claiming the
+							interface involves detaching the kernel driver.
+							Detaching the kernel driver is hard on the system
+							because it will unclaim interfaces (if another
+							app has them claimed) and the re-attachment of
+							the driver will sometimes change /dev entry names.
+							It is for these reasons that this section is
+							#if 0. For composite devices, use the interface
+							field in the hid_device_info struct to distinguish
+							between interfaces. */
+								unsigned char data[256];
+#ifdef DETACH_KERNEL_DRIVER
+								int detached = 0;
+								/* Usage Page and Usage */
+								res = libusb_kernel_driver_active(handle, interface_num);
+								if (res == 1) {
+									res = libusb_detach_kernel_driver(handle, interface_num);
+									if (res < 0)
+										LOG("Couldn't detach kernel driver, even though a kernel driver was attached.");
+									else
+										detached = 1;
+								}
+#endif
+								res = libusb_claim_interface(handle, interface_num);
+								if (res >= 0) {
+									/* Get the HID Report Descriptor. */
+									res = libusb_control_transfer(handle, LIBUSB_ENDPOINT_IN|LIBUSB_RECIPIENT_INTERFACE, LIBUSB_REQUEST_GET_DESCRIPTOR, (LIBUSB_DT_REPORT << 8)|interface_num, 0, data, sizeof(data), 5000);
+									if (res >= 0) {
+										unsigned short page=0, usage=0;
+										/* Parse the usage and usage page
+										   out of the report descriptor. */
+										get_usage(data, res,  &page, &usage);
+										cur_dev->usage_page = page;
+										cur_dev->usage = usage;
+									}
+									else
+										LOG("libusb_control_transfer() for getting the HID report failed with %d\n", res);
+
+									/* Release the interface */
+									res = libusb_release_interface(handle, interface_num);
+									if (res < 0)
+										LOG("Can't release the interface.\n");
+								}
+								else
+									LOG("Can't claim interface %d\n", res);
+#ifdef DETACH_KERNEL_DRIVER
+								/* Re-attach kernel driver if necessary. */
+								if (detached) {
+									res = libusb_attach_kernel_driver(handle, interface_num);
+									if (res < 0)
+										LOG("Couldn't re-attach kernel driver.\n");
+								}
+#endif
+}
+#endif /* INVASIVE_GET_USAGE */
+
+								libusb_close(handle);
+							}
+							/* VID/PID */
+							cur_dev->vendor_id = dev_vid;
+							cur_dev->product_id = dev_pid;
+
+							/* Release Number */
+							cur_dev->release_number = desc.bcdDevice;
+
+							/* Interface Number */
+							cur_dev->interface_number = interface_num;
+						}
+					}
+				} /* altsettings */
+			} /* interfaces */
+			libusb_free_config_descriptor(conf_desc);
+		}
+	}
+
+	libusb_free_device_list(devs, 1);
+
+	return root;
+}
+
+void  HID_API_EXPORT hid_free_enumeration(struct hid_device_info *devs)
+{
+	struct hid_device_info *d = devs;
+	while (d) {
+		struct hid_device_info *next = d->next;
+		free(d->path);
+		free(d->serial_number);
+		free(d->manufacturer_string);
+		free(d->product_string);
+		free(d);
+		d = next;
+	}
+}
+
+hid_device * hid_open(unsigned short vendor_id, unsigned short product_id, const wchar_t *serial_number)
+{
+	struct hid_device_info *devs, *cur_dev;
+	const char *path_to_open = NULL;
+	hid_device *handle = NULL;
+
+	devs = hid_enumerate(vendor_id, product_id);
+	cur_dev = devs;
+	while (cur_dev) {
+		if (cur_dev->vendor_id == vendor_id &&
+		    cur_dev->product_id == product_id) {
+			if (serial_number) {
+				if (cur_dev->serial_number &&
+				    wcscmp(serial_number, cur_dev->serial_number) == 0) {
+					path_to_open = cur_dev->path;
+					break;
+				}
+			}
+			else {
+				path_to_open = cur_dev->path;
+				break;
+			}
+		}
+		cur_dev = cur_dev->next;
+	}
+
+	if (path_to_open) {
+		/* Open the device */
+		handle = hid_open_path(path_to_open);
+	}
+
+	hid_free_enumeration(devs);
+
+	return handle;
+}
+
+static void read_callback(struct libusb_transfer *transfer)
+{
+	hid_device *dev = transfer->user_data;
+	int res;
+
+	if (transfer->status == LIBUSB_TRANSFER_COMPLETED) {
+
+		struct input_report *rpt = malloc(sizeof(*rpt));
+		rpt->data = malloc(transfer->actual_length);
+		memcpy(rpt->data, transfer->buffer, transfer->actual_length);
+		rpt->len = transfer->actual_length;
+		rpt->next = NULL;
+
+		pthread_mutex_lock(&dev->mutex);
+
+		/* Attach the new report object to the end of the list. */
+		if (dev->input_reports == NULL) {
+			/* The list is empty. Put it at the root. */
+			dev->input_reports = rpt;
+			pthread_cond_signal(&dev->condition);
+		}
+		else {
+			/* Find the end of the list and attach. */
+			struct input_report *cur = dev->input_reports;
+			int num_queued = 0;
+			while (cur->next != NULL) {
+				cur = cur->next;
+				num_queued++;
+			}
+			cur->next = rpt;
+
+			/* Pop one off if we've reached 30 in the queue. This
+			   way we don't grow forever if the user never reads
+			   anything from the device. */
+			if (num_queued > 30) {
+				return_data(dev, NULL, 0);
+			}
+		}
+		pthread_mutex_unlock(&dev->mutex);
+	}
+	else if (transfer->status == LIBUSB_TRANSFER_CANCELLED) {
+		dev->shutdown_thread = 1;
+		dev->cancelled = 1;
+		return;
+	}
+	else if (transfer->status == LIBUSB_TRANSFER_NO_DEVICE) {
+		dev->shutdown_thread = 1;
+		dev->cancelled = 1;
+		return;
+	}
+	else if (transfer->status == LIBUSB_TRANSFER_TIMED_OUT) {
+		//LOG("Timeout (normal)\n");
+	}
+	else {
+		LOG("Unknown transfer code: %d\n", transfer->status);
+	}
+
+	/* Re-submit the transfer object. */
+	res = libusb_submit_transfer(transfer);
+	if (res != 0) {
+		LOG("Unable to submit URB. libusb error code: %d\n", res);
+		dev->shutdown_thread = 1;
+		dev->cancelled = 1;
+	}
+}
+
+
+static void *read_thread(void *param)
+{
+	hid_device *dev = param;
+	unsigned char *buf;
+	const size_t length = dev->input_ep_max_packet_size;
+
+	/* Set up the transfer object. */
+	buf = malloc(length);
+	dev->transfer = libusb_alloc_transfer(0);
+	libusb_fill_interrupt_transfer(dev->transfer,
+		dev->device_handle,
+		dev->input_endpoint,
+		buf,
+		length,
+		read_callback,
+		dev,
+		5000/*timeout*/);
+
+	/* Make the first submission. Further submissions are made
+	   from inside read_callback() */
+	libusb_submit_transfer(dev->transfer);
+
+	/* Notify the main thread that the read thread is up and running. */
+	pthread_barrier_wait(&dev->barrier);
+
+	/* Handle all the events. */
+	while (!dev->shutdown_thread) {
+		int res;
+		res = libusb_handle_events(usb_context);
+		if (res < 0) {
+			/* There was an error. */
+			LOG("read_thread(): libusb reports error # %d\n", res);
+
+			/* Break out of this loop only on fatal error.*/
+			if (res != LIBUSB_ERROR_BUSY &&
+			    res != LIBUSB_ERROR_TIMEOUT &&
+			    res != LIBUSB_ERROR_OVERFLOW &&
+			    res != LIBUSB_ERROR_INTERRUPTED) {
+				break;
+			}
+		}
+	}
+
+	/* Cancel any transfer that may be pending. This call will fail
+	   if no transfers are pending, but that's OK. */
+	libusb_cancel_transfer(dev->transfer);
+
+	while (!dev->cancelled)
+		libusb_handle_events_completed(usb_context, &dev->cancelled);
+
+	/* Now that the read thread is stopping, Wake any threads which are
+	   waiting on data (in hid_read_timeout()). Do this under a mutex to
+	   make sure that a thread which is about to go to sleep waiting on
+	   the condition actually will go to sleep before the condition is
+	   signaled. */
+	pthread_mutex_lock(&dev->mutex);
+	pthread_cond_broadcast(&dev->condition);
+	pthread_mutex_unlock(&dev->mutex);
+
+	/* The dev->transfer->buffer and dev->transfer objects are cleaned up
+	   in hid_close(). They are not cleaned up here because this thread
+	   could end either due to a disconnect or due to a user
+	   call to hid_close(). In both cases the objects can be safely
+	   cleaned up after the call to pthread_join() (in hid_close()), but
+	   since hid_close() calls libusb_cancel_transfer(), on these objects,
+	   they can not be cleaned up here. */
+
+	return NULL;
+}
+
+
+hid_device * HID_API_EXPORT hid_open_path(const char *path)
+{
+	hid_device *dev = NULL;
+
+	libusb_device **devs;
+	libusb_device *usb_dev;
+	int res;
+	int d = 0;
+	int good_open = 0;
+
+	if(hid_init() < 0)
+		return NULL;
+
+	dev = new_hid_device();
+
+	libusb_get_device_list(usb_context, &devs);
+	while ((usb_dev = devs[d++]) != NULL) {
+		struct libusb_device_descriptor desc;
+		struct libusb_config_descriptor *conf_desc = NULL;
+		int i,j,k;
+		libusb_get_device_descriptor(usb_dev, &desc);
+
+		if (libusb_get_active_config_descriptor(usb_dev, &conf_desc) < 0)
+			continue;
+		for (j = 0; j < conf_desc->bNumInterfaces; j++) {
+			const struct libusb_interface *intf = &conf_desc->interface[j];
+			for (k = 0; k < intf->num_altsetting; k++) {
+				const struct libusb_interface_descriptor *intf_desc;
+				intf_desc = &intf->altsetting[k];
+				if (intf_desc->bInterfaceClass == LIBUSB_CLASS_HID) {
+					char *dev_path = make_path(usb_dev, intf_desc->bInterfaceNumber);
+					if (!strcmp(dev_path, path)) {
+						/* Matched Paths. Open this device */
+
+						/* OPEN HERE */
+						res = libusb_open(usb_dev, &dev->device_handle);
+						if (res < 0) {
+							LOG("can't open device\n");
+							free(dev_path);
+							break;
+						}
+						good_open = 1;
+#ifdef DETACH_KERNEL_DRIVER
+						/* Detach the kernel driver, but only if the
+						   device is managed by the kernel */
+						if (libusb_kernel_driver_active(dev->device_handle, intf_desc->bInterfaceNumber) == 1) {
+							res = libusb_detach_kernel_driver(dev->device_handle, intf_desc->bInterfaceNumber);
+							if (res < 0) {
+								libusb_close(dev->device_handle);
+								LOG("Unable to detach Kernel Driver\n");
+								free(dev_path);
+								good_open = 0;
+								break;
+							}
+						}
+#endif
+						res = libusb_claim_interface(dev->device_handle, intf_desc->bInterfaceNumber);
+						if (res < 0) {
+							LOG("can't claim interface %d: %d\n", intf_desc->bInterfaceNumber, res);
+							free(dev_path);
+							libusb_close(dev->device_handle);
+							good_open = 0;
+							break;
+						}
+
+						/* Store off the string descriptor indexes */
+						dev->manufacturer_index = desc.iManufacturer;
+						dev->product_index      = desc.iProduct;
+						dev->serial_index       = desc.iSerialNumber;
+
+						/* Store off the interface number */
+						dev->interface = intf_desc->bInterfaceNumber;
+
+						/* Find the INPUT and OUTPUT endpoints. An
+						   OUTPUT endpoint is not required. */
+						for (i = 0; i < intf_desc->bNumEndpoints; i++) {
+							const struct libusb_endpoint_descriptor *ep
+								= &intf_desc->endpoint[i];
+
+							/* Determine the type and direction of this
+							   endpoint. */
+							int is_interrupt =
+								(ep->bmAttributes & LIBUSB_TRANSFER_TYPE_MASK)
+							      == LIBUSB_TRANSFER_TYPE_INTERRUPT;
+							int is_output =
+								(ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK)
+							      == LIBUSB_ENDPOINT_OUT;
+							int is_input =
+								(ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK)
+							      == LIBUSB_ENDPOINT_IN;
+
+							/* Decide whether to use it for input or output. */
+							if (dev->input_endpoint == 0 &&
+							    is_interrupt && is_input) {
+								/* Use this endpoint for INPUT */
+								dev->input_endpoint = ep->bEndpointAddress;
+								dev->input_ep_max_packet_size = ep->wMaxPacketSize;
+							}
+							if (dev->output_endpoint == 0 &&
+							    is_interrupt && is_output) {
+								/* Use this endpoint for OUTPUT */
+								dev->output_endpoint = ep->bEndpointAddress;
+							}
+						}
+
+						pthread_create(&dev->thread, NULL, read_thread, dev);
+
+						/* Wait here for the read thread to be initialized. */
+						pthread_barrier_wait(&dev->barrier);
+
+					}
+					free(dev_path);
+				}
+			}
+		}
+		libusb_free_config_descriptor(conf_desc);
+
+	}
+
+	libusb_free_device_list(devs, 1);
+
+	/* If we have a good handle, return it. */
+	if (good_open) {
+		return dev;
+	}
+	else {
+		/* Unable to open any devices. */
+		free_hid_device(dev);
+		return NULL;
+	}
+}
+
+
+int HID_API_EXPORT hid_write(hid_device *dev, const unsigned char *data, size_t length)
+{
+	int res;
+	int report_number = data[0];
+	int skipped_report_id = 0;
+
+	if (report_number == 0x0) {
+		data++;
+		length--;
+		skipped_report_id = 1;
+	}
+
+
+	if (dev->output_endpoint <= 0) {
+		/* No interrupt out endpoint. Use the Control Endpoint */
+		res = libusb_control_transfer(dev->device_handle,
+			LIBUSB_REQUEST_TYPE_CLASS|LIBUSB_RECIPIENT_INTERFACE|LIBUSB_ENDPOINT_OUT,
+			0x09/*HID Set_Report*/,
+			(2/*HID output*/ << 8) | report_number,
+			dev->interface,
+			(unsigned char *)data, length,
+			1000/*timeout millis*/);
+
+		if (res < 0)
+			return -1;
+
+		if (skipped_report_id)
+			length++;
+
+		return length;
+	}
+	else {
+		/* Use the interrupt out endpoint */
+		int actual_length;
+		res = libusb_interrupt_transfer(dev->device_handle,
+			dev->output_endpoint,
+			(unsigned char*)data,
+			length,
+			&actual_length, 1000);
+
+		if (res < 0)
+			return -1;
+
+		if (skipped_report_id)
+			actual_length++;
+
+		return actual_length;
+	}
+}
+
+/* Helper function, to simplify hid_read().
+   This should be called with dev->mutex locked. */
+static int return_data(hid_device *dev, unsigned char *data, size_t length)
+{
+	/* Copy the data out of the linked list item (rpt) into the
+	   return buffer (data), and delete the liked list item. */
+	struct input_report *rpt = dev->input_reports;
+	size_t len = (length < rpt->len)? length: rpt->len;
+	if (len > 0)
+		memcpy(data, rpt->data, len);
+	dev->input_reports = rpt->next;
+	free(rpt->data);
+	free(rpt);
+	return len;
+}
+
+static void cleanup_mutex(void *param)
+{
+	hid_device *dev = param;
+	pthread_mutex_unlock(&dev->mutex);
+}
+
+
+int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t length, int milliseconds)
+{
+	int bytes_read = -1;
+
+#if 0
+	int transferred;
+	int res = libusb_interrupt_transfer(dev->device_handle, dev->input_endpoint, data, length, &transferred, 5000);
+	LOG("transferred: %d\n", transferred);
+	return transferred;
+#endif
+
+	pthread_mutex_lock(&dev->mutex);
+	pthread_cleanup_push(&cleanup_mutex, dev);
+
+	/* There's an input report queued up. Return it. */
+	if (dev->input_reports) {
+		/* Return the first one */
+		bytes_read = return_data(dev, data, length);
+		goto ret;
+	}
+
+	if (dev->shutdown_thread) {
+		/* This means the device has been disconnected.
+		   An error code of -1 should be returned. */
+		bytes_read = -1;
+		goto ret;
+	}
+
+	if (milliseconds == -1) {
+		/* Blocking */
+		while (!dev->input_reports && !dev->shutdown_thread) {
+			pthread_cond_wait(&dev->condition, &dev->mutex);
+		}
+		if (dev->input_reports) {
+			bytes_read = return_data(dev, data, length);
+		}
+	}
+	else if (milliseconds > 0) {
+		/* Non-blocking, but called with timeout. */
+		int res;
+		struct timespec ts;
+		clock_gettime(CLOCK_REALTIME, &ts);
+		ts.tv_sec += milliseconds / 1000;
+		ts.tv_nsec += (milliseconds % 1000) * 1000000;
+		if (ts.tv_nsec >= 1000000000L) {
+			ts.tv_sec++;
+			ts.tv_nsec -= 1000000000L;
+		}
+
+		while (!dev->input_reports && !dev->shutdown_thread) {
+			res = pthread_cond_timedwait(&dev->condition, &dev->mutex, &ts);
+			if (res == 0) {
+				if (dev->input_reports) {
+					bytes_read = return_data(dev, data, length);
+					break;
+				}
+
+				/* If we're here, there was a spurious wake up
+				   or the read thread was shutdown. Run the
+				   loop again (ie: don't break). */
+			}
+			else if (res == ETIMEDOUT) {
+				/* Timed out. */
+				bytes_read = 0;
+				break;
+			}
+			else {
+				/* Error. */
+				bytes_read = -1;
+				break;
+			}
+		}
+	}
+	else {
+		/* Purely non-blocking */
+		bytes_read = 0;
+	}
+
+ret:
+	pthread_mutex_unlock(&dev->mutex);
+	pthread_cleanup_pop(0);
+
+	return bytes_read;
+}
+
+int HID_API_EXPORT hid_read(hid_device *dev, unsigned char *data, size_t length)
+{
+	return hid_read_timeout(dev, data, length, dev->blocking ? -1 : 0);
+}
+
+int HID_API_EXPORT hid_set_nonblocking(hid_device *dev, int nonblock)
+{
+	dev->blocking = !nonblock;
+
+	return 0;
+}
+
+
+int HID_API_EXPORT hid_send_feature_report(hid_device *dev, const unsigned char *data, size_t length)
+{
+	int res = -1;
+	int skipped_report_id = 0;
+	int report_number = data[0];
+
+	if (report_number == 0x0) {
+		data++;
+		length--;
+		skipped_report_id = 1;
+	}
+
+	res = libusb_control_transfer(dev->device_handle,
+		LIBUSB_REQUEST_TYPE_CLASS|LIBUSB_RECIPIENT_INTERFACE|LIBUSB_ENDPOINT_OUT,
+		0x09/*HID set_report*/,
+		(3/*HID feature*/ << 8) | report_number,
+		dev->interface,
+		(unsigned char *)data, length,
+		1000/*timeout millis*/);
+
+	if (res < 0)
+		return -1;
+
+	/* Account for the report ID */
+	if (skipped_report_id)
+		length++;
+
+	return length;
+}
+
+int HID_API_EXPORT hid_get_feature_report(hid_device *dev, unsigned char *data, size_t length)
+{
+	int res = -1;
+	int skipped_report_id = 0;
+	int report_number = data[0];
+
+	if (report_number == 0x0) {
+		/* Offset the return buffer by 1, so that the report ID
+		   will remain in byte 0. */
+		data++;
+		length--;
+		skipped_report_id = 1;
+	}
+	res = libusb_control_transfer(dev->device_handle,
+		LIBUSB_REQUEST_TYPE_CLASS|LIBUSB_RECIPIENT_INTERFACE|LIBUSB_ENDPOINT_IN,
+		0x01/*HID get_report*/,
+		(3/*HID feature*/ << 8) | report_number,
+		dev->interface,
+		(unsigned char *)data, length,
+		1000/*timeout millis*/);
+
+	if (res < 0)
+		return -1;
+
+	if (skipped_report_id)
+		res++;
+
+	return res;
+}
+
+
+void HID_API_EXPORT hid_close(hid_device *dev)
+{
+	if (!dev)
+		return;
+
+	/* Cause read_thread() to stop. */
+	dev->shutdown_thread = 1;
+	libusb_cancel_transfer(dev->transfer);
+
+	/* Wait for read_thread() to end. */
+	pthread_join(dev->thread, NULL);
+
+	/* Clean up the Transfer objects allocated in read_thread(). */
+	free(dev->transfer->buffer);
+	libusb_free_transfer(dev->transfer);
+
+	/* release the interface */
+	libusb_release_interface(dev->device_handle, dev->interface);
+
+	/* Close the handle */
+	libusb_close(dev->device_handle);
+
+	/* Clear out the queue of received reports. */
+	pthread_mutex_lock(&dev->mutex);
+	while (dev->input_reports) {
+		return_data(dev, NULL, 0);
+	}
+	pthread_mutex_unlock(&dev->mutex);
+
+	free_hid_device(dev);
+}
+
+
+int HID_API_EXPORT_CALL hid_get_manufacturer_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return hid_get_indexed_string(dev, dev->manufacturer_index, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_product_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return hid_get_indexed_string(dev, dev->product_index, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_serial_number_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return hid_get_indexed_string(dev, dev->serial_index, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *dev, int string_index, wchar_t *string, size_t maxlen)
+{
+	wchar_t *str;
+
+	str = get_usb_string(dev->device_handle, string_index);
+	if (str) {
+		wcsncpy(string, str, maxlen);
+		string[maxlen-1] = L'\0';
+		free(str);
+		return 0;
+	}
+	else
+		return -1;
+}
+
+
+HID_API_EXPORT const wchar_t * HID_API_CALL  hid_error(hid_device *dev)
+{
+	return NULL;
+}
+
+
+struct lang_map_entry {
+	const char *name;
+	const char *string_code;
+	uint16_t usb_code;
+};
+
+#define LANG(name,code,usb_code) { name, code, usb_code }
+static struct lang_map_entry lang_map[] = {
+	LANG("Afrikaans", "af", 0x0436),
+	LANG("Albanian", "sq", 0x041C),
+	LANG("Arabic - United Arab Emirates", "ar_ae", 0x3801),
+	LANG("Arabic - Bahrain", "ar_bh", 0x3C01),
+	LANG("Arabic - Algeria", "ar_dz", 0x1401),
+	LANG("Arabic - Egypt", "ar_eg", 0x0C01),
+	LANG("Arabic - Iraq", "ar_iq", 0x0801),
+	LANG("Arabic - Jordan", "ar_jo", 0x2C01),
+	LANG("Arabic - Kuwait", "ar_kw", 0x3401),
+	LANG("Arabic - Lebanon", "ar_lb", 0x3001),
+	LANG("Arabic - Libya", "ar_ly", 0x1001),
+	LANG("Arabic - Morocco", "ar_ma", 0x1801),
+	LANG("Arabic - Oman", "ar_om", 0x2001),
+	LANG("Arabic - Qatar", "ar_qa", 0x4001),
+	LANG("Arabic - Saudi Arabia", "ar_sa", 0x0401),
+	LANG("Arabic - Syria", "ar_sy", 0x2801),
+	LANG("Arabic - Tunisia", "ar_tn", 0x1C01),
+	LANG("Arabic - Yemen", "ar_ye", 0x2401),
+	LANG("Armenian", "hy", 0x042B),
+	LANG("Azeri - Latin", "az_az", 0x042C),
+	LANG("Azeri - Cyrillic", "az_az", 0x082C),
+	LANG("Basque", "eu", 0x042D),
+	LANG("Belarusian", "be", 0x0423),
+	LANG("Bulgarian", "bg", 0x0402),
+	LANG("Catalan", "ca", 0x0403),
+	LANG("Chinese - China", "zh_cn", 0x0804),
+	LANG("Chinese - Hong Kong SAR", "zh_hk", 0x0C04),
+	LANG("Chinese - Macau SAR", "zh_mo", 0x1404),
+	LANG("Chinese - Singapore", "zh_sg", 0x1004),
+	LANG("Chinese - Taiwan", "zh_tw", 0x0404),
+	LANG("Croatian", "hr", 0x041A),
+	LANG("Czech", "cs", 0x0405),
+	LANG("Danish", "da", 0x0406),
+	LANG("Dutch - Netherlands", "nl_nl", 0x0413),
+	LANG("Dutch - Belgium", "nl_be", 0x0813),
+	LANG("English - Australia", "en_au", 0x0C09),
+	LANG("English - Belize", "en_bz", 0x2809),
+	LANG("English - Canada", "en_ca", 0x1009),
+	LANG("English - Caribbean", "en_cb", 0x2409),
+	LANG("English - Ireland", "en_ie", 0x1809),
+	LANG("English - Jamaica", "en_jm", 0x2009),
+	LANG("English - New Zealand", "en_nz", 0x1409),
+	LANG("English - Phillippines", "en_ph", 0x3409),
+	LANG("English - Southern Africa", "en_za", 0x1C09),
+	LANG("English - Trinidad", "en_tt", 0x2C09),
+	LANG("English - Great Britain", "en_gb", 0x0809),
+	LANG("English - United States", "en_us", 0x0409),
+	LANG("Estonian", "et", 0x0425),
+	LANG("Farsi", "fa", 0x0429),
+	LANG("Finnish", "fi", 0x040B),
+	LANG("Faroese", "fo", 0x0438),
+	LANG("French - France", "fr_fr", 0x040C),
+	LANG("French - Belgium", "fr_be", 0x080C),
+	LANG("French - Canada", "fr_ca", 0x0C0C),
+	LANG("French - Luxembourg", "fr_lu", 0x140C),
+	LANG("French - Switzerland", "fr_ch", 0x100C),
+	LANG("Gaelic - Ireland", "gd_ie", 0x083C),
+	LANG("Gaelic - Scotland", "gd", 0x043C),
+	LANG("German - Germany", "de_de", 0x0407),
+	LANG("German - Austria", "de_at", 0x0C07),
+	LANG("German - Liechtenstein", "de_li", 0x1407),
+	LANG("German - Luxembourg", "de_lu", 0x1007),
+	LANG("German - Switzerland", "de_ch", 0x0807),
+	LANG("Greek", "el", 0x0408),
+	LANG("Hebrew", "he", 0x040D),
+	LANG("Hindi", "hi", 0x0439),
+	LANG("Hungarian", "hu", 0x040E),
+	LANG("Icelandic", "is", 0x040F),
+	LANG("Indonesian", "id", 0x0421),
+	LANG("Italian - Italy", "it_it", 0x0410),
+	LANG("Italian - Switzerland", "it_ch", 0x0810),
+	LANG("Japanese", "ja", 0x0411),
+	LANG("Korean", "ko", 0x0412),
+	LANG("Latvian", "lv", 0x0426),
+	LANG("Lithuanian", "lt", 0x0427),
+	LANG("F.Y.R.O. Macedonia", "mk", 0x042F),
+	LANG("Malay - Malaysia", "ms_my", 0x043E),
+	LANG("Malay – Brunei", "ms_bn", 0x083E),
+	LANG("Maltese", "mt", 0x043A),
+	LANG("Marathi", "mr", 0x044E),
+	LANG("Norwegian - Bokml", "no_no", 0x0414),
+	LANG("Norwegian - Nynorsk", "no_no", 0x0814),
+	LANG("Polish", "pl", 0x0415),
+	LANG("Portuguese - Portugal", "pt_pt", 0x0816),
+	LANG("Portuguese - Brazil", "pt_br", 0x0416),
+	LANG("Raeto-Romance", "rm", 0x0417),
+	LANG("Romanian - Romania", "ro", 0x0418),
+	LANG("Romanian - Republic of Moldova", "ro_mo", 0x0818),
+	LANG("Russian", "ru", 0x0419),
+	LANG("Russian - Republic of Moldova", "ru_mo", 0x0819),
+	LANG("Sanskrit", "sa", 0x044F),
+	LANG("Serbian - Cyrillic", "sr_sp", 0x0C1A),
+	LANG("Serbian - Latin", "sr_sp", 0x081A),
+	LANG("Setsuana", "tn", 0x0432),
+	LANG("Slovenian", "sl", 0x0424),
+	LANG("Slovak", "sk", 0x041B),
+	LANG("Sorbian", "sb", 0x042E),
+	LANG("Spanish - Spain (Traditional)", "es_es", 0x040A),
+	LANG("Spanish - Argentina", "es_ar", 0x2C0A),
+	LANG("Spanish - Bolivia", "es_bo", 0x400A),
+	LANG("Spanish - Chile", "es_cl", 0x340A),
+	LANG("Spanish - Colombia", "es_co", 0x240A),
+	LANG("Spanish - Costa Rica", "es_cr", 0x140A),
+	LANG("Spanish - Dominican Republic", "es_do", 0x1C0A),
+	LANG("Spanish - Ecuador", "es_ec", 0x300A),
+	LANG("Spanish - Guatemala", "es_gt", 0x100A),
+	LANG("Spanish - Honduras", "es_hn", 0x480A),
+	LANG("Spanish - Mexico", "es_mx", 0x080A),
+	LANG("Spanish - Nicaragua", "es_ni", 0x4C0A),
+	LANG("Spanish - Panama", "es_pa", 0x180A),
+	LANG("Spanish - Peru", "es_pe", 0x280A),
+	LANG("Spanish - Puerto Rico", "es_pr", 0x500A),
+	LANG("Spanish - Paraguay", "es_py", 0x3C0A),
+	LANG("Spanish - El Salvador", "es_sv", 0x440A),
+	LANG("Spanish - Uruguay", "es_uy", 0x380A),
+	LANG("Spanish - Venezuela", "es_ve", 0x200A),
+	LANG("Southern Sotho", "st", 0x0430),
+	LANG("Swahili", "sw", 0x0441),
+	LANG("Swedish - Sweden", "sv_se", 0x041D),
+	LANG("Swedish - Finland", "sv_fi", 0x081D),
+	LANG("Tamil", "ta", 0x0449),
+	LANG("Tatar", "tt", 0X0444),
+	LANG("Thai", "th", 0x041E),
+	LANG("Turkish", "tr", 0x041F),
+	LANG("Tsonga", "ts", 0x0431),
+	LANG("Ukrainian", "uk", 0x0422),
+	LANG("Urdu", "ur", 0x0420),
+	LANG("Uzbek - Cyrillic", "uz_uz", 0x0843),
+	LANG("Uzbek – Latin", "uz_uz", 0x0443),
+	LANG("Vietnamese", "vi", 0x042A),
+	LANG("Xhosa", "xh", 0x0434),
+	LANG("Yiddish", "yi", 0x043D),
+	LANG("Zulu", "zu", 0x0435),
+	LANG(NULL, NULL, 0x0),
+};
+
+uint16_t get_usb_code_for_current_locale(void)
+{
+	char *locale;
+	char search_string[64];
+	char *ptr;
+	struct lang_map_entry *lang;
+
+	/* Get the current locale. */
+	locale = setlocale(0, NULL);
+	if (!locale)
+		return 0x0;
+
+	/* Make a copy of the current locale string. */
+	strncpy(search_string, locale, sizeof(search_string));
+	search_string[sizeof(search_string)-1] = '\0';
+
+	/* Chop off the encoding part, and make it lower case. */
+	ptr = search_string;
+	while (*ptr) {
+		*ptr = tolower(*ptr);
+		if (*ptr == '.') {
+			*ptr = '\0';
+			break;
+		}
+		ptr++;
+	}
+
+	/* Find the entry which matches the string code of our locale. */
+	lang = lang_map;
+	while (lang->string_code) {
+		if (!strcmp(lang->string_code, search_string)) {
+			return lang->usb_code;
+		}
+		lang++;
+	}
+
+	/* There was no match. Find with just the language only. */
+	/* Chop off the variant. Chop it off at the '_'. */
+	ptr = search_string;
+	while (*ptr) {
+		*ptr = tolower(*ptr);
+		if (*ptr == '_') {
+			*ptr = '\0';
+			break;
+		}
+		ptr++;
+	}
+
+#if 0 /* TODO: Do we need this? */
+	/* Find the entry which matches the string code of our language. */
+	lang = lang_map;
+	while (lang->string_code) {
+		if (!strcmp(lang->string_code, search_string)) {
+			return lang->usb_code;
+		}
+		lang++;
+	}
+#endif
+
+	/* Found nothing. */
+	return 0x0;
+}
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/vendor/github.com/karalabe/hid/hidapi/mac/hid.c b/vendor/github.com/karalabe/hid/hidapi/mac/hid.c
new file mode 100644
index 000000000..e0756a158
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/mac/hid.c
@@ -0,0 +1,1110 @@
+/*******************************************************
+ HIDAPI - Multi-Platform library for
+ communication with HID devices.
+
+ Alan Ott
+ Signal 11 Software
+
+ 2010-07-03
+
+ Copyright 2010, All Rights Reserved.
+
+ At the discretion of the user of this library,
+ this software may be licensed under the terms of the
+ GNU General Public License v3, a BSD-Style license, or the
+ original HIDAPI license as outlined in the LICENSE.txt,
+ LICENSE-gpl3.txt, LICENSE-bsd.txt, and LICENSE-orig.txt
+ files located at the root of the source distribution.
+ These files may also be found in the public source
+ code repository located at:
+        http://github.com/signal11/hidapi .
+********************************************************/
+
+/* See Apple Technical Note TN2187 for details on IOHidManager. */
+
+#include <IOKit/hid/IOHIDManager.h>
+#include <IOKit/hid/IOHIDKeys.h>
+#include <IOKit/IOKitLib.h>
+#include <CoreFoundation/CoreFoundation.h>
+#include <wchar.h>
+#include <locale.h>
+#include <pthread.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <dlfcn.h>
+
+#include "hidapi.h"
+
+/* Barrier implementation because Mac OSX doesn't have pthread_barrier.
+   It also doesn't have clock_gettime(). So much for POSIX and SUSv2.
+   This implementation came from Brent Priddy and was posted on
+   StackOverflow. It is used with his permission. */
+typedef int pthread_barrierattr_t;
+typedef struct pthread_barrier {
+    pthread_mutex_t mutex;
+    pthread_cond_t cond;
+    int count;
+    int trip_count;
+} pthread_barrier_t;
+
+static int pthread_barrier_init(pthread_barrier_t *barrier, const pthread_barrierattr_t *attr, unsigned int count)
+{
+	if(count == 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if(pthread_mutex_init(&barrier->mutex, 0) < 0) {
+		return -1;
+	}
+	if(pthread_cond_init(&barrier->cond, 0) < 0) {
+		pthread_mutex_destroy(&barrier->mutex);
+		return -1;
+	}
+	barrier->trip_count = count;
+	barrier->count = 0;
+
+	return 0;
+}
+
+static int pthread_barrier_destroy(pthread_barrier_t *barrier)
+{
+	pthread_cond_destroy(&barrier->cond);
+	pthread_mutex_destroy(&barrier->mutex);
+	return 0;
+}
+
+static int pthread_barrier_wait(pthread_barrier_t *barrier)
+{
+	pthread_mutex_lock(&barrier->mutex);
+	++(barrier->count);
+	if(barrier->count >= barrier->trip_count)
+	{
+		barrier->count = 0;
+		pthread_cond_broadcast(&barrier->cond);
+		pthread_mutex_unlock(&barrier->mutex);
+		return 1;
+	}
+	else
+	{
+		pthread_cond_wait(&barrier->cond, &(barrier->mutex));
+		pthread_mutex_unlock(&barrier->mutex);
+		return 0;
+	}
+}
+
+static int return_data(hid_device *dev, unsigned char *data, size_t length);
+
+/* Linked List of input reports received from the device. */
+struct input_report {
+	uint8_t *data;
+	size_t len;
+	struct input_report *next;
+};
+
+struct hid_device_ {
+	IOHIDDeviceRef device_handle;
+	int blocking;
+	int uses_numbered_reports;
+	int disconnected;
+	CFStringRef run_loop_mode;
+	CFRunLoopRef run_loop;
+	CFRunLoopSourceRef source;
+	uint8_t *input_report_buf;
+	CFIndex max_input_report_len;
+	struct input_report *input_reports;
+
+	pthread_t thread;
+	pthread_mutex_t mutex; /* Protects input_reports */
+	pthread_cond_t condition;
+	pthread_barrier_t barrier; /* Ensures correct startup sequence */
+	pthread_barrier_t shutdown_barrier; /* Ensures correct shutdown sequence */
+	int shutdown_thread;
+};
+
+static hid_device *new_hid_device(void)
+{
+	hid_device *dev = calloc(1, sizeof(hid_device));
+	dev->device_handle = NULL;
+	dev->blocking = 1;
+	dev->uses_numbered_reports = 0;
+	dev->disconnected = 0;
+	dev->run_loop_mode = NULL;
+	dev->run_loop = NULL;
+	dev->source = NULL;
+	dev->input_report_buf = NULL;
+	dev->input_reports = NULL;
+	dev->shutdown_thread = 0;
+
+	/* Thread objects */
+	pthread_mutex_init(&dev->mutex, NULL);
+	pthread_cond_init(&dev->condition, NULL);
+	pthread_barrier_init(&dev->barrier, NULL, 2);
+	pthread_barrier_init(&dev->shutdown_barrier, NULL, 2);
+
+	return dev;
+}
+
+static void free_hid_device(hid_device *dev)
+{
+	if (!dev)
+		return;
+
+	/* Delete any input reports still left over. */
+	struct input_report *rpt = dev->input_reports;
+	while (rpt) {
+		struct input_report *next = rpt->next;
+		free(rpt->data);
+		free(rpt);
+		rpt = next;
+	}
+
+	/* Free the string and the report buffer. The check for NULL
+	   is necessary here as CFRelease() doesn't handle NULL like
+	   free() and others do. */
+	if (dev->run_loop_mode)
+		CFRelease(dev->run_loop_mode);
+	if (dev->source)
+		CFRelease(dev->source);
+	free(dev->input_report_buf);
+
+	/* Clean up the thread objects */
+	pthread_barrier_destroy(&dev->shutdown_barrier);
+	pthread_barrier_destroy(&dev->barrier);
+	pthread_cond_destroy(&dev->condition);
+	pthread_mutex_destroy(&dev->mutex);
+
+	/* Free the structure itself. */
+	free(dev);
+}
+
+static	IOHIDManagerRef hid_mgr = 0x0;
+
+
+#if 0
+static void register_error(hid_device *device, const char *op)
+{
+
+}
+#endif
+
+
+static int32_t get_int_property(IOHIDDeviceRef device, CFStringRef key)
+{
+	CFTypeRef ref;
+	int32_t value;
+
+	ref = IOHIDDeviceGetProperty(device, key);
+	if (ref) {
+		if (CFGetTypeID(ref) == CFNumberGetTypeID()) {
+			CFNumberGetValue((CFNumberRef) ref, kCFNumberSInt32Type, &value);
+			return value;
+		}
+	}
+	return 0;
+}
+
+static unsigned short get_vendor_id(IOHIDDeviceRef device)
+{
+	return get_int_property(device, CFSTR(kIOHIDVendorIDKey));
+}
+
+static unsigned short get_product_id(IOHIDDeviceRef device)
+{
+	return get_int_property(device, CFSTR(kIOHIDProductIDKey));
+}
+
+static int32_t get_max_report_length(IOHIDDeviceRef device)
+{
+	return get_int_property(device, CFSTR(kIOHIDMaxInputReportSizeKey));
+}
+
+static int get_string_property(IOHIDDeviceRef device, CFStringRef prop, wchar_t *buf, size_t len)
+{
+	CFStringRef str;
+
+	if (!len)
+		return 0;
+
+	str = IOHIDDeviceGetProperty(device, prop);
+
+	buf[0] = 0;
+
+	if (str) {
+		CFIndex str_len = CFStringGetLength(str);
+		CFRange range;
+		CFIndex used_buf_len;
+		CFIndex chars_copied;
+
+		len --;
+
+		range.location = 0;
+		range.length = ((size_t)str_len > len)? len: (size_t)str_len;
+		chars_copied = CFStringGetBytes(str,
+			range,
+			kCFStringEncodingUTF32LE,
+			(char)'?',
+			FALSE,
+			(UInt8*)buf,
+			len * sizeof(wchar_t),
+			&used_buf_len);
+
+		if (chars_copied == len)
+			buf[len] = 0; /* len is decremented above */
+		else
+			buf[chars_copied] = 0;
+
+		return 0;
+	}
+	else
+		return -1;
+
+}
+
+static int get_serial_number(IOHIDDeviceRef device, wchar_t *buf, size_t len)
+{
+	return get_string_property(device, CFSTR(kIOHIDSerialNumberKey), buf, len);
+}
+
+static int get_manufacturer_string(IOHIDDeviceRef device, wchar_t *buf, size_t len)
+{
+	return get_string_property(device, CFSTR(kIOHIDManufacturerKey), buf, len);
+}
+
+static int get_product_string(IOHIDDeviceRef device, wchar_t *buf, size_t len)
+{
+	return get_string_property(device, CFSTR(kIOHIDProductKey), buf, len);
+}
+
+
+/* Implementation of wcsdup() for Mac. */
+static wchar_t *dup_wcs(const wchar_t *s)
+{
+	size_t len = wcslen(s);
+	wchar_t *ret = malloc((len+1)*sizeof(wchar_t));
+	wcscpy(ret, s);
+
+	return ret;
+}
+
+/* hidapi_IOHIDDeviceGetService()
+ *
+ * Return the io_service_t corresponding to a given IOHIDDeviceRef, either by:
+ * - on OS X 10.6 and above, calling IOHIDDeviceGetService()
+ * - on OS X 10.5, extract it from the IOHIDDevice struct
+ */
+static io_service_t hidapi_IOHIDDeviceGetService(IOHIDDeviceRef device)
+{
+	static void *iokit_framework = NULL;
+	static io_service_t (*dynamic_IOHIDDeviceGetService)(IOHIDDeviceRef device) = NULL;
+
+	/* Use dlopen()/dlsym() to get a pointer to IOHIDDeviceGetService() if it exists.
+	 * If any of these steps fail, dynamic_IOHIDDeviceGetService will be left NULL
+	 * and the fallback method will be used.
+	 */
+	if (iokit_framework == NULL) {
+		iokit_framework = dlopen("/System/Library/IOKit.framework/IOKit", RTLD_LAZY);
+
+		if (iokit_framework != NULL)
+			dynamic_IOHIDDeviceGetService = dlsym(iokit_framework, "IOHIDDeviceGetService");
+	}
+
+	if (dynamic_IOHIDDeviceGetService != NULL) {
+		/* Running on OS X 10.6 and above: IOHIDDeviceGetService() exists */
+		return dynamic_IOHIDDeviceGetService(device);
+	}
+	else
+	{
+		/* Running on OS X 10.5: IOHIDDeviceGetService() doesn't exist.
+		 *
+		 * Be naughty and pull the service out of the IOHIDDevice.
+		 * IOHIDDevice is an opaque struct not exposed to applications, but its
+		 * layout is stable through all available versions of OS X.
+		 * Tested and working on OS X 10.5.8 i386, x86_64, and ppc.
+		 */
+		struct IOHIDDevice_internal {
+			/* The first field of the IOHIDDevice struct is a
+			 * CFRuntimeBase (which is a private CF struct).
+			 *
+			 * a, b, and c are the 3 fields that make up a CFRuntimeBase.
+			 * See http://opensource.apple.com/source/CF/CF-476.18/CFRuntime.h
+			 *
+			 * The second field of the IOHIDDevice is the io_service_t we're looking for.
+			 */
+			uintptr_t a;
+			uint8_t b[4];
+#if __LP64__
+			uint32_t c;
+#endif
+			io_service_t service;
+		};
+		struct IOHIDDevice_internal *tmp = (struct IOHIDDevice_internal *)device;
+
+		return tmp->service;
+	}
+}
+
+/* Initialize the IOHIDManager. Return 0 for success and -1 for failure. */
+static int init_hid_manager(void)
+{
+	/* Initialize all the HID Manager Objects */
+	hid_mgr = IOHIDManagerCreate(kCFAllocatorDefault, kIOHIDOptionsTypeNone);
+	if (hid_mgr) {
+		IOHIDManagerSetDeviceMatching(hid_mgr, NULL);
+		IOHIDManagerScheduleWithRunLoop(hid_mgr, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
+		return 0;
+	}
+
+	return -1;
+}
+
+/* Initialize the IOHIDManager if necessary. This is the public function, and
+   it is safe to call this function repeatedly. Return 0 for success and -1
+   for failure. */
+int HID_API_EXPORT hid_init(void)
+{
+	if (!hid_mgr) {
+		return init_hid_manager();
+	}
+
+	/* Already initialized. */
+	return 0;
+}
+
+int HID_API_EXPORT hid_exit(void)
+{
+	if (hid_mgr) {
+		/* Close the HID manager. */
+		IOHIDManagerClose(hid_mgr, kIOHIDOptionsTypeNone);
+		CFRelease(hid_mgr);
+		hid_mgr = NULL;
+	}
+
+	return 0;
+}
+
+static void process_pending_events(void) {
+	SInt32 res;
+	do {
+		res = CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0.001, FALSE);
+	} while(res != kCFRunLoopRunFinished && res != kCFRunLoopRunTimedOut);
+}
+
+struct hid_device_info  HID_API_EXPORT *hid_enumerate(unsigned short vendor_id, unsigned short product_id)
+{
+	struct hid_device_info *root = NULL; /* return object */
+	struct hid_device_info *cur_dev = NULL;
+	CFIndex num_devices;
+	int i;
+
+	/* Set up the HID Manager if it hasn't been done */
+	if (hid_init() < 0)
+		return NULL;
+
+	/* give the IOHIDManager a chance to update itself */
+	process_pending_events();
+
+	/* Get a list of the Devices */
+	IOHIDManagerSetDeviceMatching(hid_mgr, NULL);
+	CFSetRef device_set = IOHIDManagerCopyDevices(hid_mgr);
+
+	/* Convert the list into a C array so we can iterate easily. */
+	num_devices = CFSetGetCount(device_set);
+	IOHIDDeviceRef *device_array = calloc(num_devices, sizeof(IOHIDDeviceRef));
+	CFSetGetValues(device_set, (const void **) device_array);
+
+	/* Iterate over each device, making an entry for it. */
+	for (i = 0; i < num_devices; i++) {
+		unsigned short dev_vid;
+		unsigned short dev_pid;
+		#define BUF_LEN 256
+		wchar_t buf[BUF_LEN];
+
+		IOHIDDeviceRef dev = device_array[i];
+
+        if (!dev) {
+            continue;
+        }
+		dev_vid = get_vendor_id(dev);
+		dev_pid = get_product_id(dev);
+
+		/* Check the VID/PID against the arguments */
+		if ((vendor_id == 0x0 || vendor_id == dev_vid) &&
+		    (product_id == 0x0 || product_id == dev_pid)) {
+			struct hid_device_info *tmp;
+			io_object_t iokit_dev;
+			kern_return_t res;
+			io_string_t path;
+
+			/* VID/PID match. Create the record. */
+			tmp = malloc(sizeof(struct hid_device_info));
+			if (cur_dev) {
+				cur_dev->next = tmp;
+			}
+			else {
+				root = tmp;
+			}
+			cur_dev = tmp;
+
+			/* Get the Usage Page and Usage for this device. */
+			cur_dev->usage_page = get_int_property(dev, CFSTR(kIOHIDPrimaryUsagePageKey));
+			cur_dev->usage = get_int_property(dev, CFSTR(kIOHIDPrimaryUsageKey));
+
+			/* Fill out the record */
+			cur_dev->next = NULL;
+
+			/* Fill in the path (IOService plane) */
+			iokit_dev = hidapi_IOHIDDeviceGetService(dev);
+			res = IORegistryEntryGetPath(iokit_dev, kIOServicePlane, path);
+			if (res == KERN_SUCCESS)
+				cur_dev->path = strdup(path);
+			else
+				cur_dev->path = strdup("");
+
+			/* Serial Number */
+			get_serial_number(dev, buf, BUF_LEN);
+			cur_dev->serial_number = dup_wcs(buf);
+
+			/* Manufacturer and Product strings */
+			get_manufacturer_string(dev, buf, BUF_LEN);
+			cur_dev->manufacturer_string = dup_wcs(buf);
+			get_product_string(dev, buf, BUF_LEN);
+			cur_dev->product_string = dup_wcs(buf);
+
+			/* VID/PID */
+			cur_dev->vendor_id = dev_vid;
+			cur_dev->product_id = dev_pid;
+
+			/* Release Number */
+			cur_dev->release_number = get_int_property(dev, CFSTR(kIOHIDVersionNumberKey));
+
+			/* Interface Number (Unsupported on Mac)*/
+			cur_dev->interface_number = -1;
+		}
+	}
+
+	free(device_array);
+	CFRelease(device_set);
+
+	return root;
+}
+
+void  HID_API_EXPORT hid_free_enumeration(struct hid_device_info *devs)
+{
+	/* This function is identical to the Linux version. Platform independent. */
+	struct hid_device_info *d = devs;
+	while (d) {
+		struct hid_device_info *next = d->next;
+		free(d->path);
+		free(d->serial_number);
+		free(d->manufacturer_string);
+		free(d->product_string);
+		free(d);
+		d = next;
+	}
+}
+
+hid_device * HID_API_EXPORT hid_open(unsigned short vendor_id, unsigned short product_id, const wchar_t *serial_number)
+{
+	/* This function is identical to the Linux version. Platform independent. */
+	struct hid_device_info *devs, *cur_dev;
+	const char *path_to_open = NULL;
+	hid_device * handle = NULL;
+
+	devs = hid_enumerate(vendor_id, product_id);
+	cur_dev = devs;
+	while (cur_dev) {
+		if (cur_dev->vendor_id == vendor_id &&
+		    cur_dev->product_id == product_id) {
+			if (serial_number) {
+				if (wcscmp(serial_number, cur_dev->serial_number) == 0) {
+					path_to_open = cur_dev->path;
+					break;
+				}
+			}
+			else {
+				path_to_open = cur_dev->path;
+				break;
+			}
+		}
+		cur_dev = cur_dev->next;
+	}
+
+	if (path_to_open) {
+		/* Open the device */
+		handle = hid_open_path(path_to_open);
+	}
+
+	hid_free_enumeration(devs);
+
+	return handle;
+}
+
+static void hid_device_removal_callback(void *context, IOReturn result,
+                                        void *sender)
+{
+	/* Stop the Run Loop for this device. */
+	hid_device *d = context;
+
+	d->disconnected = 1;
+	CFRunLoopStop(d->run_loop);
+}
+
+/* The Run Loop calls this function for each input report received.
+   This function puts the data into a linked list to be picked up by
+   hid_read(). */
+static void hid_report_callback(void *context, IOReturn result, void *sender,
+                         IOHIDReportType report_type, uint32_t report_id,
+                         uint8_t *report, CFIndex report_length)
+{
+	struct input_report *rpt;
+	hid_device *dev = context;
+
+	/* Make a new Input Report object */
+	rpt = calloc(1, sizeof(struct input_report));
+	rpt->data = calloc(1, report_length);
+	memcpy(rpt->data, report, report_length);
+	rpt->len = report_length;
+	rpt->next = NULL;
+
+	/* Lock this section */
+	pthread_mutex_lock(&dev->mutex);
+
+	/* Attach the new report object to the end of the list. */
+	if (dev->input_reports == NULL) {
+		/* The list is empty. Put it at the root. */
+		dev->input_reports = rpt;
+	}
+	else {
+		/* Find the end of the list and attach. */
+		struct input_report *cur = dev->input_reports;
+		int num_queued = 0;
+		while (cur->next != NULL) {
+			cur = cur->next;
+			num_queued++;
+		}
+		cur->next = rpt;
+
+		/* Pop one off if we've reached 30 in the queue. This
+		   way we don't grow forever if the user never reads
+		   anything from the device. */
+		if (num_queued > 30) {
+			return_data(dev, NULL, 0);
+		}
+	}
+
+	/* Signal a waiting thread that there is data. */
+	pthread_cond_signal(&dev->condition);
+
+	/* Unlock */
+	pthread_mutex_unlock(&dev->mutex);
+
+}
+
+/* This gets called when the read_thread's run loop gets signaled by
+   hid_close(), and serves to stop the read_thread's run loop. */
+static void perform_signal_callback(void *context)
+{
+	hid_device *dev = context;
+	CFRunLoopStop(dev->run_loop); /*TODO: CFRunLoopGetCurrent()*/
+}
+
+static void *read_thread(void *param)
+{
+	hid_device *dev = param;
+	SInt32 code;
+
+	/* Move the device's run loop to this thread. */
+	IOHIDDeviceScheduleWithRunLoop(dev->device_handle, CFRunLoopGetCurrent(), dev->run_loop_mode);
+
+	/* Create the RunLoopSource which is used to signal the
+	   event loop to stop when hid_close() is called. */
+	CFRunLoopSourceContext ctx;
+	memset(&ctx, 0, sizeof(ctx));
+	ctx.version = 0;
+	ctx.info = dev;
+	ctx.perform = &perform_signal_callback;
+	dev->source = CFRunLoopSourceCreate(kCFAllocatorDefault, 0/*order*/, &ctx);
+	CFRunLoopAddSource(CFRunLoopGetCurrent(), dev->source, dev->run_loop_mode);
+
+	/* Store off the Run Loop so it can be stopped from hid_close()
+	   and on device disconnection. */
+	dev->run_loop = CFRunLoopGetCurrent();
+
+	/* Notify the main thread that the read thread is up and running. */
+	pthread_barrier_wait(&dev->barrier);
+
+	/* Run the Event Loop. CFRunLoopRunInMode() will dispatch HID input
+	   reports into the hid_report_callback(). */
+	while (!dev->shutdown_thread && !dev->disconnected) {
+		code = CFRunLoopRunInMode(dev->run_loop_mode, 1000/*sec*/, FALSE);
+		/* Return if the device has been disconnected */
+		if (code == kCFRunLoopRunFinished) {
+			dev->disconnected = 1;
+			break;
+		}
+
+
+		/* Break if The Run Loop returns Finished or Stopped. */
+		if (code != kCFRunLoopRunTimedOut &&
+		    code != kCFRunLoopRunHandledSource) {
+			/* There was some kind of error. Setting
+			   shutdown seems to make sense, but
+			   there may be something else more appropriate */
+			dev->shutdown_thread = 1;
+			break;
+		}
+	}
+
+	/* Now that the read thread is stopping, Wake any threads which are
+	   waiting on data (in hid_read_timeout()). Do this under a mutex to
+	   make sure that a thread which is about to go to sleep waiting on
+	   the condition actually will go to sleep before the condition is
+	   signaled. */
+	pthread_mutex_lock(&dev->mutex);
+	pthread_cond_broadcast(&dev->condition);
+	pthread_mutex_unlock(&dev->mutex);
+
+	/* Wait here until hid_close() is called and makes it past
+	   the call to CFRunLoopWakeUp(). This thread still needs to
+	   be valid when that function is called on the other thread. */
+	pthread_barrier_wait(&dev->shutdown_barrier);
+
+	return NULL;
+}
+
+/* hid_open_path()
+ *
+ * path must be a valid path to an IOHIDDevice in the IOService plane
+ * Example: "IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/EHC1@1D,7/AppleUSBEHCI/PLAYSTATION(R)3 Controller@fd120000/IOUSBInterface@0/IOUSBHIDDriver"
+ */
+hid_device * HID_API_EXPORT hid_open_path(const char *path)
+{
+	hid_device *dev = NULL;
+	io_registry_entry_t entry = MACH_PORT_NULL;
+
+	dev = new_hid_device();
+
+	/* Set up the HID Manager if it hasn't been done */
+	if (hid_init() < 0)
+		return NULL;
+
+	/* Get the IORegistry entry for the given path */
+	entry = IORegistryEntryFromPath(kIOMasterPortDefault, path);
+	if (entry == MACH_PORT_NULL) {
+		/* Path wasn't valid (maybe device was removed?) */
+		goto return_error;
+	}
+
+	/* Create an IOHIDDevice for the entry */
+	dev->device_handle = IOHIDDeviceCreate(kCFAllocatorDefault, entry);
+	if (dev->device_handle == NULL) {
+		/* Error creating the HID device */
+		goto return_error;
+	}
+
+	/* Open the IOHIDDevice */
+	IOReturn ret = IOHIDDeviceOpen(dev->device_handle, kIOHIDOptionsTypeSeizeDevice);
+	if (ret == kIOReturnSuccess) {
+		char str[32];
+
+		/* Create the buffers for receiving data */
+		dev->max_input_report_len = (CFIndex) get_max_report_length(dev->device_handle);
+		dev->input_report_buf = calloc(dev->max_input_report_len, sizeof(uint8_t));
+
+		/* Create the Run Loop Mode for this device.
+		   printing the reference seems to work. */
+		sprintf(str, "HIDAPI_%p", dev->device_handle);
+		dev->run_loop_mode =
+			CFStringCreateWithCString(NULL, str, kCFStringEncodingASCII);
+
+		/* Attach the device to a Run Loop */
+		IOHIDDeviceRegisterInputReportCallback(
+			dev->device_handle, dev->input_report_buf, dev->max_input_report_len,
+			&hid_report_callback, dev);
+		IOHIDDeviceRegisterRemovalCallback(dev->device_handle, hid_device_removal_callback, dev);
+
+		/* Start the read thread */
+		pthread_create(&dev->thread, NULL, read_thread, dev);
+
+		/* Wait here for the read thread to be initialized. */
+		pthread_barrier_wait(&dev->barrier);
+
+		IOObjectRelease(entry);
+		return dev;
+	}
+	else {
+		goto return_error;
+	}
+
+return_error:
+	if (dev->device_handle != NULL)
+		CFRelease(dev->device_handle);
+
+	if (entry != MACH_PORT_NULL)
+		IOObjectRelease(entry);
+
+	free_hid_device(dev);
+	return NULL;
+}
+
+static int set_report(hid_device *dev, IOHIDReportType type, const unsigned char *data, size_t length)
+{
+	const unsigned char *data_to_send;
+	size_t length_to_send;
+	IOReturn res;
+
+	/* Return if the device has been disconnected. */
+	if (dev->disconnected)
+		return -1;
+
+	if (data[0] == 0x0) {
+		/* Not using numbered Reports.
+		   Don't send the report number. */
+		data_to_send = data+1;
+		length_to_send = length-1;
+	}
+	else {
+		/* Using numbered Reports.
+		   Send the Report Number */
+		data_to_send = data;
+		length_to_send = length;
+	}
+
+	if (!dev->disconnected) {
+		res = IOHIDDeviceSetReport(dev->device_handle,
+					   type,
+					   data[0], /* Report ID*/
+					   data_to_send, length_to_send);
+
+		if (res == kIOReturnSuccess) {
+			return length;
+		}
+		else
+			return -1;
+	}
+
+	return -1;
+}
+
+int HID_API_EXPORT hid_write(hid_device *dev, const unsigned char *data, size_t length)
+{
+	return set_report(dev, kIOHIDReportTypeOutput, data, length);
+}
+
+/* Helper function, so that this isn't duplicated in hid_read(). */
+static int return_data(hid_device *dev, unsigned char *data, size_t length)
+{
+	/* Copy the data out of the linked list item (rpt) into the
+	   return buffer (data), and delete the liked list item. */
+	struct input_report *rpt = dev->input_reports;
+	size_t len = (length < rpt->len)? length: rpt->len;
+	memcpy(data, rpt->data, len);
+	dev->input_reports = rpt->next;
+	free(rpt->data);
+	free(rpt);
+	return len;
+}
+
+static int cond_wait(const hid_device *dev, pthread_cond_t *cond, pthread_mutex_t *mutex)
+{
+	while (!dev->input_reports) {
+		int res = pthread_cond_wait(cond, mutex);
+		if (res != 0)
+			return res;
+
+		/* A res of 0 means we may have been signaled or it may
+		   be a spurious wakeup. Check to see that there's acutally
+		   data in the queue before returning, and if not, go back
+		   to sleep. See the pthread_cond_timedwait() man page for
+		   details. */
+
+		if (dev->shutdown_thread || dev->disconnected)
+			return -1;
+	}
+
+	return 0;
+}
+
+static int cond_timedwait(const hid_device *dev, pthread_cond_t *cond, pthread_mutex_t *mutex, const struct timespec *abstime)
+{
+	while (!dev->input_reports) {
+		int res = pthread_cond_timedwait(cond, mutex, abstime);
+		if (res != 0)
+			return res;
+
+		/* A res of 0 means we may have been signaled or it may
+		   be a spurious wakeup. Check to see that there's acutally
+		   data in the queue before returning, and if not, go back
+		   to sleep. See the pthread_cond_timedwait() man page for
+		   details. */
+
+		if (dev->shutdown_thread || dev->disconnected)
+			return -1;
+	}
+
+	return 0;
+
+}
+
+int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t length, int milliseconds)
+{
+	int bytes_read = -1;
+
+	/* Lock the access to the report list. */
+	pthread_mutex_lock(&dev->mutex);
+
+	/* There's an input report queued up. Return it. */
+	if (dev->input_reports) {
+		/* Return the first one */
+		bytes_read = return_data(dev, data, length);
+		goto ret;
+	}
+
+	/* Return if the device has been disconnected. */
+	if (dev->disconnected) {
+		bytes_read = -1;
+		goto ret;
+	}
+
+	if (dev->shutdown_thread) {
+		/* This means the device has been closed (or there
+		   has been an error. An error code of -1 should
+		   be returned. */
+		bytes_read = -1;
+		goto ret;
+	}
+
+	/* There is no data. Go to sleep and wait for data. */
+
+	if (milliseconds == -1) {
+		/* Blocking */
+		int res;
+		res = cond_wait(dev, &dev->condition, &dev->mutex);
+		if (res == 0)
+			bytes_read = return_data(dev, data, length);
+		else {
+			/* There was an error, or a device disconnection. */
+			bytes_read = -1;
+		}
+	}
+	else if (milliseconds > 0) {
+		/* Non-blocking, but called with timeout. */
+		int res;
+		struct timespec ts;
+		struct timeval tv;
+		gettimeofday(&tv, NULL);
+		TIMEVAL_TO_TIMESPEC(&tv, &ts);
+		ts.tv_sec += milliseconds / 1000;
+		ts.tv_nsec += (milliseconds % 1000) * 1000000;
+		if (ts.tv_nsec >= 1000000000L) {
+			ts.tv_sec++;
+			ts.tv_nsec -= 1000000000L;
+		}
+
+		res = cond_timedwait(dev, &dev->condition, &dev->mutex, &ts);
+		if (res == 0)
+			bytes_read = return_data(dev, data, length);
+		else if (res == ETIMEDOUT)
+			bytes_read = 0;
+		else
+			bytes_read = -1;
+	}
+	else {
+		/* Purely non-blocking */
+		bytes_read = 0;
+	}
+
+ret:
+	/* Unlock */
+	pthread_mutex_unlock(&dev->mutex);
+	return bytes_read;
+}
+
+int HID_API_EXPORT hid_read(hid_device *dev, unsigned char *data, size_t length)
+{
+	return hid_read_timeout(dev, data, length, (dev->blocking)? -1: 0);
+}
+
+int HID_API_EXPORT hid_set_nonblocking(hid_device *dev, int nonblock)
+{
+	/* All Nonblocking operation is handled by the library. */
+	dev->blocking = !nonblock;
+
+	return 0;
+}
+
+int HID_API_EXPORT hid_send_feature_report(hid_device *dev, const unsigned char *data, size_t length)
+{
+	return set_report(dev, kIOHIDReportTypeFeature, data, length);
+}
+
+int HID_API_EXPORT hid_get_feature_report(hid_device *dev, unsigned char *data, size_t length)
+{
+	CFIndex len = length;
+	IOReturn res;
+
+	/* Return if the device has been unplugged. */
+	if (dev->disconnected)
+		return -1;
+
+	res = IOHIDDeviceGetReport(dev->device_handle,
+	                           kIOHIDReportTypeFeature,
+	                           data[0], /* Report ID */
+	                           data, &len);
+	if (res == kIOReturnSuccess)
+		return len;
+	else
+		return -1;
+}
+
+
+void HID_API_EXPORT hid_close(hid_device *dev)
+{
+	if (!dev)
+		return;
+
+	/* Disconnect the report callback before close. */
+	if (!dev->disconnected) {
+		IOHIDDeviceRegisterInputReportCallback(
+			dev->device_handle, dev->input_report_buf, dev->max_input_report_len,
+			NULL, dev);
+		IOHIDDeviceRegisterRemovalCallback(dev->device_handle, NULL, dev);
+		IOHIDDeviceUnscheduleFromRunLoop(dev->device_handle, dev->run_loop, dev->run_loop_mode);
+		IOHIDDeviceScheduleWithRunLoop(dev->device_handle, CFRunLoopGetMain(), kCFRunLoopDefaultMode);
+	}
+
+	/* Cause read_thread() to stop. */
+	dev->shutdown_thread = 1;
+
+	/* Wake up the run thread's event loop so that the thread can exit. */
+	CFRunLoopSourceSignal(dev->source);
+	CFRunLoopWakeUp(dev->run_loop);
+
+	/* Notify the read thread that it can shut down now. */
+	pthread_barrier_wait(&dev->shutdown_barrier);
+
+	/* Wait for read_thread() to end. */
+	pthread_join(dev->thread, NULL);
+
+	/* Close the OS handle to the device, but only if it's not
+	   been unplugged. If it's been unplugged, then calling
+	   IOHIDDeviceClose() will crash. */
+	if (!dev->disconnected) {
+		IOHIDDeviceClose(dev->device_handle, kIOHIDOptionsTypeSeizeDevice);
+	}
+
+	/* Clear out the queue of received reports. */
+	pthread_mutex_lock(&dev->mutex);
+	while (dev->input_reports) {
+		return_data(dev, NULL, 0);
+	}
+	pthread_mutex_unlock(&dev->mutex);
+	CFRelease(dev->device_handle);
+
+	free_hid_device(dev);
+}
+
+int HID_API_EXPORT_CALL hid_get_manufacturer_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return get_manufacturer_string(dev->device_handle, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_product_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return get_product_string(dev->device_handle, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_serial_number_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	return get_serial_number(dev->device_handle, string, maxlen);
+}
+
+int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *dev, int string_index, wchar_t *string, size_t maxlen)
+{
+	/* TODO: */
+
+	return 0;
+}
+
+
+HID_API_EXPORT const wchar_t * HID_API_CALL  hid_error(hid_device *dev)
+{
+	/* TODO: */
+
+	return NULL;
+}
+
+
+
+
+
+
+
+#if 0
+static int32_t get_location_id(IOHIDDeviceRef device)
+{
+	return get_int_property(device, CFSTR(kIOHIDLocationIDKey));
+}
+
+static int32_t get_usage(IOHIDDeviceRef device)
+{
+	int32_t res;
+	res = get_int_property(device, CFSTR(kIOHIDDeviceUsageKey));
+	if (!res)
+		res = get_int_property(device, CFSTR(kIOHIDPrimaryUsageKey));
+	return res;
+}
+
+static int32_t get_usage_page(IOHIDDeviceRef device)
+{
+	int32_t res;
+	res = get_int_property(device, CFSTR(kIOHIDDeviceUsagePageKey));
+	if (!res)
+		res = get_int_property(device, CFSTR(kIOHIDPrimaryUsagePageKey));
+	return res;
+}
+
+static int get_transport(IOHIDDeviceRef device, wchar_t *buf, size_t len)
+{
+	return get_string_property(device, CFSTR(kIOHIDTransportKey), buf, len);
+}
+
+
+int main(void)
+{
+	IOHIDManagerRef mgr;
+	int i;
+
+	mgr = IOHIDManagerCreate(kCFAllocatorDefault, kIOHIDOptionsTypeNone);
+	IOHIDManagerSetDeviceMatching(mgr, NULL);
+	IOHIDManagerOpen(mgr, kIOHIDOptionsTypeNone);
+
+	CFSetRef device_set = IOHIDManagerCopyDevices(mgr);
+
+	CFIndex num_devices = CFSetGetCount(device_set);
+	IOHIDDeviceRef *device_array = calloc(num_devices, sizeof(IOHIDDeviceRef));
+	CFSetGetValues(device_set, (const void **) device_array);
+
+	for (i = 0; i < num_devices; i++) {
+		IOHIDDeviceRef dev = device_array[i];
+		printf("Device: %p\n", dev);
+		printf("  %04hx %04hx\n", get_vendor_id(dev), get_product_id(dev));
+
+		wchar_t serial[256], buf[256];
+		char cbuf[256];
+		get_serial_number(dev, serial, 256);
+
+
+		printf("  Serial: %ls\n", serial);
+		printf("  Loc: %ld\n", get_location_id(dev));
+		get_transport(dev, buf, 256);
+		printf("  Trans: %ls\n", buf);
+		make_path(dev, cbuf, 256);
+		printf("  Path: %s\n", cbuf);
+
+	}
+
+	return 0;
+}
+#endif
diff --git a/vendor/github.com/karalabe/hid/hidapi/windows/hid.c b/vendor/github.com/karalabe/hid/hidapi/windows/hid.c
new file mode 100755
index 000000000..86810d7e5
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/hidapi/windows/hid.c
@@ -0,0 +1,944 @@
+/*******************************************************
+ HIDAPI - Multi-Platform library for
+ communication with HID devices.
+
+ Alan Ott
+ Signal 11 Software
+
+ 8/22/2009
+
+ Copyright 2009, All Rights Reserved.
+ 
+ At the discretion of the user of this library,
+ this software may be licensed under the terms of the
+ GNU General Public License v3, a BSD-Style license, or the
+ original HIDAPI license as outlined in the LICENSE.txt,
+ LICENSE-gpl3.txt, LICENSE-bsd.txt, and LICENSE-orig.txt
+ files located at the root of the source distribution.
+ These files may also be found in the public source
+ code repository located at:
+        http://github.com/signal11/hidapi .
+********************************************************/
+
+#include <windows.h>
+
+#ifndef _NTDEF_
+typedef LONG NTSTATUS;
+#endif
+
+#ifdef __MINGW32__
+#include <ntdef.h>
+#include <winbase.h>
+#endif
+
+#ifdef __CYGWIN__
+#include <ntdef.h>
+#define _wcsdup wcsdup
+#endif
+
+/* The maximum number of characters that can be passed into the
+   HidD_Get*String() functions without it failing.*/
+#define MAX_STRING_WCHARS 0xFFF
+
+/*#define HIDAPI_USE_DDK*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+	#include <setupapi.h>
+	#include <winioctl.h>
+	#ifdef HIDAPI_USE_DDK
+		#include <hidsdi.h>
+	#endif
+
+	/* Copied from inc/ddk/hidclass.h, part of the Windows DDK. */
+	#define HID_OUT_CTL_CODE(id)  \
+		CTL_CODE(FILE_DEVICE_KEYBOARD, (id), METHOD_OUT_DIRECT, FILE_ANY_ACCESS)
+	#define IOCTL_HID_GET_FEATURE                   HID_OUT_CTL_CODE(100)
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+
+
+#include "hidapi.h"
+
+#undef MIN
+#define MIN(x,y) ((x) < (y)? (x): (y))
+
+#ifdef _MSC_VER
+	/* Thanks Microsoft, but I know how to use strncpy(). */
+	#pragma warning(disable:4996)
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef HIDAPI_USE_DDK
+	/* Since we're not building with the DDK, and the HID header
+	   files aren't part of the SDK, we have to define all this
+	   stuff here. In lookup_functions(), the function pointers
+	   defined below are set. */
+	typedef struct _HIDD_ATTRIBUTES{
+		ULONG Size;
+		USHORT VendorID;
+		USHORT ProductID;
+		USHORT VersionNumber;
+	} HIDD_ATTRIBUTES, *PHIDD_ATTRIBUTES;
+
+	typedef USHORT USAGE;
+	typedef struct _HIDP_CAPS {
+		USAGE Usage;
+		USAGE UsagePage;
+		USHORT InputReportByteLength;
+		USHORT OutputReportByteLength;
+		USHORT FeatureReportByteLength;
+		USHORT Reserved[17];
+		USHORT fields_not_used_by_hidapi[10];
+	} HIDP_CAPS, *PHIDP_CAPS;
+	typedef void* PHIDP_PREPARSED_DATA;
+	#define HIDP_STATUS_SUCCESS 0x110000
+
+	typedef BOOLEAN (__stdcall *HidD_GetAttributes_)(HANDLE device, PHIDD_ATTRIBUTES attrib);
+	typedef BOOLEAN (__stdcall *HidD_GetSerialNumberString_)(HANDLE device, PVOID buffer, ULONG buffer_len);
+	typedef BOOLEAN (__stdcall *HidD_GetManufacturerString_)(HANDLE handle, PVOID buffer, ULONG buffer_len);
+	typedef BOOLEAN (__stdcall *HidD_GetProductString_)(HANDLE handle, PVOID buffer, ULONG buffer_len);
+	typedef BOOLEAN (__stdcall *HidD_SetFeature_)(HANDLE handle, PVOID data, ULONG length);
+	typedef BOOLEAN (__stdcall *HidD_GetFeature_)(HANDLE handle, PVOID data, ULONG length);
+	typedef BOOLEAN (__stdcall *HidD_GetIndexedString_)(HANDLE handle, ULONG string_index, PVOID buffer, ULONG buffer_len);
+	typedef BOOLEAN (__stdcall *HidD_GetPreparsedData_)(HANDLE handle, PHIDP_PREPARSED_DATA *preparsed_data);
+	typedef BOOLEAN (__stdcall *HidD_FreePreparsedData_)(PHIDP_PREPARSED_DATA preparsed_data);
+	typedef NTSTATUS (__stdcall *HidP_GetCaps_)(PHIDP_PREPARSED_DATA preparsed_data, HIDP_CAPS *caps);
+	typedef BOOLEAN (__stdcall *HidD_SetNumInputBuffers_)(HANDLE handle, ULONG number_buffers);
+
+	static HidD_GetAttributes_ HidD_GetAttributes;
+	static HidD_GetSerialNumberString_ HidD_GetSerialNumberString;
+	static HidD_GetManufacturerString_ HidD_GetManufacturerString;
+	static HidD_GetProductString_ HidD_GetProductString;
+	static HidD_SetFeature_ HidD_SetFeature;
+	static HidD_GetFeature_ HidD_GetFeature;
+	static HidD_GetIndexedString_ HidD_GetIndexedString;
+	static HidD_GetPreparsedData_ HidD_GetPreparsedData;
+	static HidD_FreePreparsedData_ HidD_FreePreparsedData;
+	static HidP_GetCaps_ HidP_GetCaps;
+	static HidD_SetNumInputBuffers_ HidD_SetNumInputBuffers;
+
+	static HMODULE lib_handle = NULL;
+	static BOOLEAN initialized = FALSE;
+#endif /* HIDAPI_USE_DDK */
+
+struct hid_device_ {
+		HANDLE device_handle;
+		BOOL blocking;
+		USHORT output_report_length;
+		size_t input_report_length;
+		void *last_error_str;
+		DWORD last_error_num;
+		BOOL read_pending;
+		char *read_buf;
+		OVERLAPPED ol;
+};
+
+static hid_device *new_hid_device()
+{
+	hid_device *dev = (hid_device*) calloc(1, sizeof(hid_device));
+	dev->device_handle = INVALID_HANDLE_VALUE;
+	dev->blocking = TRUE;
+	dev->output_report_length = 0;
+	dev->input_report_length = 0;
+	dev->last_error_str = NULL;
+	dev->last_error_num = 0;
+	dev->read_pending = FALSE;
+	dev->read_buf = NULL;
+	memset(&dev->ol, 0, sizeof(dev->ol));
+	dev->ol.hEvent = CreateEvent(NULL, FALSE, FALSE /*initial state f=nonsignaled*/, NULL);
+
+	return dev;
+}
+
+static void free_hid_device(hid_device *dev)
+{
+	CloseHandle(dev->ol.hEvent);
+	CloseHandle(dev->device_handle);
+	LocalFree(dev->last_error_str);
+	free(dev->read_buf);
+	free(dev);
+}
+
+static void register_error(hid_device *device, const char *op)
+{
+	WCHAR *ptr, *msg;
+
+	FormatMessageW(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+		FORMAT_MESSAGE_FROM_SYSTEM |
+		FORMAT_MESSAGE_IGNORE_INSERTS,
+		NULL,
+		GetLastError(),
+		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+		(LPVOID)&msg, 0/*sz*/,
+		NULL);
+	
+	/* Get rid of the CR and LF that FormatMessage() sticks at the
+	   end of the message. Thanks Microsoft! */
+	ptr = msg;
+	while (*ptr) {
+		if (*ptr == '\r') {
+			*ptr = 0x0000;
+			break;
+		}
+		ptr++;
+	}
+
+	/* Store the message off in the Device entry so that
+	   the hid_error() function can pick it up. */
+	LocalFree(device->last_error_str);
+	device->last_error_str = msg;
+}
+
+#ifndef HIDAPI_USE_DDK
+static int lookup_functions()
+{
+	lib_handle = LoadLibraryA("hid.dll");
+	if (lib_handle) {
+#define RESOLVE(x) x = (x##_)GetProcAddress(lib_handle, #x); if (!x) return -1;
+		RESOLVE(HidD_GetAttributes);
+		RESOLVE(HidD_GetSerialNumberString);
+		RESOLVE(HidD_GetManufacturerString);
+		RESOLVE(HidD_GetProductString);
+		RESOLVE(HidD_SetFeature);
+		RESOLVE(HidD_GetFeature);
+		RESOLVE(HidD_GetIndexedString);
+		RESOLVE(HidD_GetPreparsedData);
+		RESOLVE(HidD_FreePreparsedData);
+		RESOLVE(HidP_GetCaps);
+		RESOLVE(HidD_SetNumInputBuffers);
+#undef RESOLVE
+	}
+	else
+		return -1;
+
+	return 0;
+}
+#endif
+
+static HANDLE open_device(const char *path, BOOL enumerate)
+{
+	HANDLE handle;
+	DWORD desired_access = (enumerate)? 0: (GENERIC_WRITE | GENERIC_READ);
+	DWORD share_mode = FILE_SHARE_READ|FILE_SHARE_WRITE;
+
+	handle = CreateFileA(path,
+		desired_access,
+		share_mode,
+		NULL,
+		OPEN_EXISTING,
+		FILE_FLAG_OVERLAPPED,/*FILE_ATTRIBUTE_NORMAL,*/
+		0);
+
+	return handle;
+}
+
+int HID_API_EXPORT hid_init(void)
+{
+#ifndef HIDAPI_USE_DDK
+	if (!initialized) {
+		if (lookup_functions() < 0) {
+			hid_exit();
+			return -1;
+		}
+		initialized = TRUE;
+	}
+#endif
+	return 0;
+}
+
+int HID_API_EXPORT hid_exit(void)
+{
+#ifndef HIDAPI_USE_DDK
+	if (lib_handle)
+		FreeLibrary(lib_handle);
+	lib_handle = NULL;
+	initialized = FALSE;
+#endif
+	return 0;
+}
+
+struct hid_device_info HID_API_EXPORT * HID_API_CALL hid_enumerate(unsigned short vendor_id, unsigned short product_id)
+{
+	BOOL res;
+	struct hid_device_info *root = NULL; /* return object */
+	struct hid_device_info *cur_dev = NULL;
+
+	/* Windows objects for interacting with the driver. */
+	GUID InterfaceClassGuid = {0x4d1e55b2, 0xf16f, 0x11cf, {0x88, 0xcb, 0x00, 0x11, 0x11, 0x00, 0x00, 0x30} };
+	SP_DEVINFO_DATA devinfo_data;
+	SP_DEVICE_INTERFACE_DATA device_interface_data;
+	SP_DEVICE_INTERFACE_DETAIL_DATA_A *device_interface_detail_data = NULL;
+	HDEVINFO device_info_set = INVALID_HANDLE_VALUE;
+	int device_index = 0;
+	int i;
+
+	if (hid_init() < 0)
+		return NULL;
+
+	/* Initialize the Windows objects. */
+	memset(&devinfo_data, 0x0, sizeof(devinfo_data));
+	devinfo_data.cbSize = sizeof(SP_DEVINFO_DATA);
+	device_interface_data.cbSize = sizeof(SP_DEVICE_INTERFACE_DATA);
+
+	/* Get information for all the devices belonging to the HID class. */
+	device_info_set = SetupDiGetClassDevsA(&InterfaceClassGuid, NULL, NULL, DIGCF_PRESENT | DIGCF_DEVICEINTERFACE);
+	
+	/* Iterate over each device in the HID class, looking for the right one. */
+	
+	for (;;) {
+		HANDLE write_handle = INVALID_HANDLE_VALUE;
+		DWORD required_size = 0;
+		HIDD_ATTRIBUTES attrib;
+
+		res = SetupDiEnumDeviceInterfaces(device_info_set,
+			NULL,
+			&InterfaceClassGuid,
+			device_index,
+			&device_interface_data);
+		
+		if (!res) {
+			/* A return of FALSE from this function means that
+			   there are no more devices. */
+			break;
+		}
+
+		/* Call with 0-sized detail size, and let the function
+		   tell us how long the detail struct needs to be. The
+		   size is put in &required_size. */
+		res = SetupDiGetDeviceInterfaceDetailA(device_info_set,
+			&device_interface_data,
+			NULL,
+			0,
+			&required_size,
+			NULL);
+
+		/* Allocate a long enough structure for device_interface_detail_data. */
+		device_interface_detail_data = (SP_DEVICE_INTERFACE_DETAIL_DATA_A*) malloc(required_size);
+		device_interface_detail_data->cbSize = sizeof(SP_DEVICE_INTERFACE_DETAIL_DATA_A);
+
+		/* Get the detailed data for this device. The detail data gives us
+		   the device path for this device, which is then passed into
+		   CreateFile() to get a handle to the device. */
+		res = SetupDiGetDeviceInterfaceDetailA(device_info_set,
+			&device_interface_data,
+			device_interface_detail_data,
+			required_size,
+			NULL,
+			NULL);
+
+		if (!res) {
+			/* register_error(dev, "Unable to call SetupDiGetDeviceInterfaceDetail");
+			   Continue to the next device. */
+			goto cont;
+		}
+
+		/* Make sure this device is of Setup Class "HIDClass" and has a
+		   driver bound to it. */
+		for (i = 0; ; i++) {
+			char driver_name[256];
+
+			/* Populate devinfo_data. This function will return failure
+			   when there are no more interfaces left. */
+			res = SetupDiEnumDeviceInfo(device_info_set, i, &devinfo_data);
+			if (!res)
+				goto cont;
+
+			res = SetupDiGetDeviceRegistryPropertyA(device_info_set, &devinfo_data,
+			               SPDRP_CLASS, NULL, (PBYTE)driver_name, sizeof(driver_name), NULL);
+			if (!res)
+				goto cont;
+
+			if (strcmp(driver_name, "HIDClass") == 0) {
+				/* See if there's a driver bound. */
+				res = SetupDiGetDeviceRegistryPropertyA(device_info_set, &devinfo_data,
+				           SPDRP_DRIVER, NULL, (PBYTE)driver_name, sizeof(driver_name), NULL);
+				if (res)
+					break;
+			}
+		}
+
+		//wprintf(L"HandleName: %s\n", device_interface_detail_data->DevicePath);
+
+		/* Open a handle to the device */
+		write_handle = open_device(device_interface_detail_data->DevicePath, TRUE);
+
+		/* Check validity of write_handle. */
+		if (write_handle == INVALID_HANDLE_VALUE) {
+			/* Unable to open the device. */
+			//register_error(dev, "CreateFile");
+			goto cont_close;
+		}		
+
+
+		/* Get the Vendor ID and Product ID for this device. */
+		attrib.Size = sizeof(HIDD_ATTRIBUTES);
+		HidD_GetAttributes(write_handle, &attrib);
+		//wprintf(L"Product/Vendor: %x %x\n", attrib.ProductID, attrib.VendorID);
+
+		/* Check the VID/PID to see if we should add this
+		   device to the enumeration list. */
+		if ((vendor_id == 0x0 || attrib.VendorID == vendor_id) &&
+		    (product_id == 0x0 || attrib.ProductID == product_id)) {
+
+			#define WSTR_LEN 512
+			const char *str;
+			struct hid_device_info *tmp;
+			PHIDP_PREPARSED_DATA pp_data = NULL;
+			HIDP_CAPS caps;
+			BOOLEAN res;
+			NTSTATUS nt_res;
+			wchar_t wstr[WSTR_LEN]; /* TODO: Determine Size */
+			size_t len;
+
+			/* VID/PID match. Create the record. */
+			tmp = (struct hid_device_info*) calloc(1, sizeof(struct hid_device_info));
+			if (cur_dev) {
+				cur_dev->next = tmp;
+			}
+			else {
+				root = tmp;
+			}
+			cur_dev = tmp;
+
+			/* Get the Usage Page and Usage for this device. */
+			res = HidD_GetPreparsedData(write_handle, &pp_data);
+			if (res) {
+				nt_res = HidP_GetCaps(pp_data, &caps);
+				if (nt_res == HIDP_STATUS_SUCCESS) {
+					cur_dev->usage_page = caps.UsagePage;
+					cur_dev->usage = caps.Usage;
+				}
+
+				HidD_FreePreparsedData(pp_data);
+			}
+			
+			/* Fill out the record */
+			cur_dev->next = NULL;
+			str = device_interface_detail_data->DevicePath;
+			if (str) {
+				len = strlen(str);
+				cur_dev->path = (char*) calloc(len+1, sizeof(char));
+				strncpy(cur_dev->path, str, len+1);
+				cur_dev->path[len] = '\0';
+			}
+			else
+				cur_dev->path = NULL;
+
+			/* Serial Number */
+			res = HidD_GetSerialNumberString(write_handle, wstr, sizeof(wstr));
+			wstr[WSTR_LEN-1] = 0x0000;
+			if (res) {
+				cur_dev->serial_number = _wcsdup(wstr);
+			}
+
+			/* Manufacturer String */
+			res = HidD_GetManufacturerString(write_handle, wstr, sizeof(wstr));
+			wstr[WSTR_LEN-1] = 0x0000;
+			if (res) {
+				cur_dev->manufacturer_string = _wcsdup(wstr);
+			}
+
+			/* Product String */
+			res = HidD_GetProductString(write_handle, wstr, sizeof(wstr));
+			wstr[WSTR_LEN-1] = 0x0000;
+			if (res) {
+				cur_dev->product_string = _wcsdup(wstr);
+			}
+
+			/* VID/PID */
+			cur_dev->vendor_id = attrib.VendorID;
+			cur_dev->product_id = attrib.ProductID;
+
+			/* Release Number */
+			cur_dev->release_number = attrib.VersionNumber;
+
+			/* Interface Number. It can sometimes be parsed out of the path
+			   on Windows if a device has multiple interfaces. See
+			   http://msdn.microsoft.com/en-us/windows/hardware/gg487473 or
+			   search for "Hardware IDs for HID Devices" at MSDN. If it's not
+			   in the path, it's set to -1. */
+			cur_dev->interface_number = -1;
+			if (cur_dev->path) {
+				char *interface_component = strstr(cur_dev->path, "&mi_");
+				if (interface_component) {
+					char *hex_str = interface_component + 4;
+					char *endptr = NULL;
+					cur_dev->interface_number = strtol(hex_str, &endptr, 16);
+					if (endptr == hex_str) {
+						/* The parsing failed. Set interface_number to -1. */
+						cur_dev->interface_number = -1;
+					}
+				}
+			}
+		}
+
+cont_close:
+		CloseHandle(write_handle);
+cont:
+		/* We no longer need the detail data. It can be freed */
+		free(device_interface_detail_data);
+
+		device_index++;
+
+	}
+
+	/* Close the device information handle. */
+	SetupDiDestroyDeviceInfoList(device_info_set);
+
+	return root;
+
+}
+
+void  HID_API_EXPORT HID_API_CALL hid_free_enumeration(struct hid_device_info *devs)
+{
+	/* TODO: Merge this with the Linux version. This function is platform-independent. */
+	struct hid_device_info *d = devs;
+	while (d) {
+		struct hid_device_info *next = d->next;
+		free(d->path);
+		free(d->serial_number);
+		free(d->manufacturer_string);
+		free(d->product_string);
+		free(d);
+		d = next;
+	}
+}
+
+
+HID_API_EXPORT hid_device * HID_API_CALL hid_open(unsigned short vendor_id, unsigned short product_id, const wchar_t *serial_number)
+{
+	/* TODO: Merge this functions with the Linux version. This function should be platform independent. */
+	struct hid_device_info *devs, *cur_dev;
+	const char *path_to_open = NULL;
+	hid_device *handle = NULL;
+	
+	devs = hid_enumerate(vendor_id, product_id);
+	cur_dev = devs;
+	while (cur_dev) {
+		if (cur_dev->vendor_id == vendor_id &&
+		    cur_dev->product_id == product_id) {
+			if (serial_number) {
+				if (wcscmp(serial_number, cur_dev->serial_number) == 0) {
+					path_to_open = cur_dev->path;
+					break;
+				}
+			}
+			else {
+				path_to_open = cur_dev->path;
+				break;
+			}
+		}
+		cur_dev = cur_dev->next;
+	}
+
+	if (path_to_open) {
+		/* Open the device */
+		handle = hid_open_path(path_to_open);
+	}
+
+	hid_free_enumeration(devs);
+	
+	return handle;
+}
+
+HID_API_EXPORT hid_device * HID_API_CALL hid_open_path(const char *path)
+{
+	hid_device *dev;
+	HIDP_CAPS caps;
+	PHIDP_PREPARSED_DATA pp_data = NULL;
+	BOOLEAN res;
+	NTSTATUS nt_res;
+
+	if (hid_init() < 0) {
+		return NULL;
+	}
+
+	dev = new_hid_device();
+
+	/* Open a handle to the device */
+	dev->device_handle = open_device(path, FALSE);
+
+	/* Check validity of write_handle. */
+	if (dev->device_handle == INVALID_HANDLE_VALUE) {
+		/* Unable to open the device. */
+		register_error(dev, "CreateFile");
+		goto err;
+	}
+
+	/* Set the Input Report buffer size to 64 reports. */
+	res = HidD_SetNumInputBuffers(dev->device_handle, 64);
+	if (!res) {
+		register_error(dev, "HidD_SetNumInputBuffers");
+		goto err;
+	}
+
+	/* Get the Input Report length for the device. */
+	res = HidD_GetPreparsedData(dev->device_handle, &pp_data);
+	if (!res) {
+		register_error(dev, "HidD_GetPreparsedData");
+		goto err;
+	}
+	nt_res = HidP_GetCaps(pp_data, &caps);
+	if (nt_res != HIDP_STATUS_SUCCESS) {
+		register_error(dev, "HidP_GetCaps");	
+		goto err_pp_data;
+	}
+	dev->output_report_length = caps.OutputReportByteLength;
+	dev->input_report_length = caps.InputReportByteLength;
+	HidD_FreePreparsedData(pp_data);
+
+	dev->read_buf = (char*) malloc(dev->input_report_length);
+
+	return dev;
+
+err_pp_data:
+		HidD_FreePreparsedData(pp_data);
+err:	
+		free_hid_device(dev);
+		return NULL;
+}
+
+int HID_API_EXPORT HID_API_CALL hid_write(hid_device *dev, const unsigned char *data, size_t length)
+{
+	DWORD bytes_written;
+	BOOL res;
+
+	OVERLAPPED ol;
+	unsigned char *buf;
+	memset(&ol, 0, sizeof(ol));
+
+	/* Make sure the right number of bytes are passed to WriteFile. Windows
+	   expects the number of bytes which are in the _longest_ report (plus
+	   one for the report number) bytes even if the data is a report
+	   which is shorter than that. Windows gives us this value in
+	   caps.OutputReportByteLength. If a user passes in fewer bytes than this,
+	   create a temporary buffer which is the proper size. */
+	if (length >= dev->output_report_length) {
+		/* The user passed the right number of bytes. Use the buffer as-is. */
+		buf = (unsigned char *) data;
+	} else {
+		/* Create a temporary buffer and copy the user's data
+		   into it, padding the rest with zeros. */
+		buf = (unsigned char *) malloc(dev->output_report_length);
+		memcpy(buf, data, length);
+		memset(buf + length, 0, dev->output_report_length - length);
+		length = dev->output_report_length;
+	}
+
+	res = WriteFile(dev->device_handle, buf, length, NULL, &ol);
+	
+	if (!res) {
+		if (GetLastError() != ERROR_IO_PENDING) {
+			/* WriteFile() failed. Return error. */
+			register_error(dev, "WriteFile");
+			bytes_written = -1;
+			goto end_of_function;
+		}
+	}
+
+	/* Wait here until the write is done. This makes
+	   hid_write() synchronous. */
+	res = GetOverlappedResult(dev->device_handle, &ol, &bytes_written, TRUE/*wait*/);
+	if (!res) {
+		/* The Write operation failed. */
+		register_error(dev, "WriteFile");
+		bytes_written = -1;
+		goto end_of_function;
+	}
+
+end_of_function:
+	if (buf != data)
+		free(buf);
+
+	return bytes_written;
+}
+
+
+int HID_API_EXPORT HID_API_CALL hid_read_timeout(hid_device *dev, unsigned char *data, size_t length, int milliseconds)
+{
+	DWORD bytes_read = 0;
+	size_t copy_len = 0;
+	BOOL res;
+
+	/* Copy the handle for convenience. */
+	HANDLE ev = dev->ol.hEvent;
+
+	if (!dev->read_pending) {
+		/* Start an Overlapped I/O read. */
+		dev->read_pending = TRUE;
+		memset(dev->read_buf, 0, dev->input_report_length);
+		ResetEvent(ev);
+		res = ReadFile(dev->device_handle, dev->read_buf, dev->input_report_length, &bytes_read, &dev->ol);
+		
+		if (!res) {
+			if (GetLastError() != ERROR_IO_PENDING) {
+				/* ReadFile() has failed.
+				   Clean up and return error. */
+				CancelIo(dev->device_handle);
+				dev->read_pending = FALSE;
+				goto end_of_function;
+			}
+		}
+	}
+
+	if (milliseconds >= 0) {
+		/* See if there is any data yet. */
+		res = WaitForSingleObject(ev, milliseconds);
+		if (res != WAIT_OBJECT_0) {
+			/* There was no data this time. Return zero bytes available,
+			   but leave the Overlapped I/O running. */
+			return 0;
+		}
+	}
+
+	/* Either WaitForSingleObject() told us that ReadFile has completed, or
+	   we are in non-blocking mode. Get the number of bytes read. The actual
+	   data has been copied to the data[] array which was passed to ReadFile(). */
+	res = GetOverlappedResult(dev->device_handle, &dev->ol, &bytes_read, TRUE/*wait*/);
+	
+	/* Set pending back to false, even if GetOverlappedResult() returned error. */
+	dev->read_pending = FALSE;
+
+	if (res && bytes_read > 0) {
+		if (dev->read_buf[0] == 0x0) {
+			/* If report numbers aren't being used, but Windows sticks a report
+			   number (0x0) on the beginning of the report anyway. To make this
+			   work like the other platforms, and to make it work more like the
+			   HID spec, we'll skip over this byte. */
+			bytes_read--;
+			copy_len = length > bytes_read ? bytes_read : length;
+			memcpy(data, dev->read_buf+1, copy_len);
+		}
+		else {
+			/* Copy the whole buffer, report number and all. */
+			copy_len = length > bytes_read ? bytes_read : length;
+			memcpy(data, dev->read_buf, copy_len);
+		}
+	}
+	
+end_of_function:
+	if (!res) {
+		register_error(dev, "GetOverlappedResult");
+		return -1;
+	}
+	
+	return copy_len;
+}
+
+int HID_API_EXPORT HID_API_CALL hid_read(hid_device *dev, unsigned char *data, size_t length)
+{
+	return hid_read_timeout(dev, data, length, (dev->blocking)? -1: 0);
+}
+
+int HID_API_EXPORT HID_API_CALL hid_set_nonblocking(hid_device *dev, int nonblock)
+{
+	dev->blocking = !nonblock;
+	return 0; /* Success */
+}
+
+int HID_API_EXPORT HID_API_CALL hid_send_feature_report(hid_device *dev, const unsigned char *data, size_t length)
+{
+	BOOL res = HidD_SetFeature(dev->device_handle, (PVOID)data, length);
+	if (!res) {
+		register_error(dev, "HidD_SetFeature");
+		return -1;
+	}
+
+	return length;
+}
+
+
+int HID_API_EXPORT HID_API_CALL hid_get_feature_report(hid_device *dev, unsigned char *data, size_t length)
+{
+	BOOL res;
+#if 0
+	res = HidD_GetFeature(dev->device_handle, data, length);
+	if (!res) {
+		register_error(dev, "HidD_GetFeature");
+		return -1;
+	}
+	return 0; /* HidD_GetFeature() doesn't give us an actual length, unfortunately */
+#else
+	DWORD bytes_returned;
+
+	OVERLAPPED ol;
+	memset(&ol, 0, sizeof(ol));
+
+	res = DeviceIoControl(dev->device_handle,
+		IOCTL_HID_GET_FEATURE,
+		data, length,
+		data, length,
+		&bytes_returned, &ol);
+
+	if (!res) {
+		if (GetLastError() != ERROR_IO_PENDING) {
+			/* DeviceIoControl() failed. Return error. */
+			register_error(dev, "Send Feature Report DeviceIoControl");
+			return -1;
+		}
+	}
+
+	/* Wait here until the write is done. This makes
+	   hid_get_feature_report() synchronous. */
+	res = GetOverlappedResult(dev->device_handle, &ol, &bytes_returned, TRUE/*wait*/);
+	if (!res) {
+		/* The operation failed. */
+		register_error(dev, "Send Feature Report GetOverLappedResult");
+		return -1;
+	}
+
+	/* bytes_returned does not include the first byte which contains the
+	   report ID. The data buffer actually contains one more byte than
+	   bytes_returned. */
+	bytes_returned++;
+
+	return bytes_returned;
+#endif
+}
+
+void HID_API_EXPORT HID_API_CALL hid_close(hid_device *dev)
+{
+	if (!dev)
+		return;
+	CancelIo(dev->device_handle);
+	free_hid_device(dev);
+}
+
+int HID_API_EXPORT_CALL HID_API_CALL hid_get_manufacturer_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	BOOL res;
+
+	res = HidD_GetManufacturerString(dev->device_handle, string, sizeof(wchar_t) * MIN(maxlen, MAX_STRING_WCHARS));
+	if (!res) {
+		register_error(dev, "HidD_GetManufacturerString");
+		return -1;
+	}
+
+	return 0;
+}
+
+int HID_API_EXPORT_CALL HID_API_CALL hid_get_product_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	BOOL res;
+
+	res = HidD_GetProductString(dev->device_handle, string, sizeof(wchar_t) * MIN(maxlen, MAX_STRING_WCHARS));
+	if (!res) {
+		register_error(dev, "HidD_GetProductString");
+		return -1;
+	}
+
+	return 0;
+}
+
+int HID_API_EXPORT_CALL HID_API_CALL hid_get_serial_number_string(hid_device *dev, wchar_t *string, size_t maxlen)
+{
+	BOOL res;
+
+	res = HidD_GetSerialNumberString(dev->device_handle, string, sizeof(wchar_t) * MIN(maxlen, MAX_STRING_WCHARS));
+	if (!res) {
+		register_error(dev, "HidD_GetSerialNumberString");
+		return -1;
+	}
+
+	return 0;
+}
+
+int HID_API_EXPORT_CALL HID_API_CALL hid_get_indexed_string(hid_device *dev, int string_index, wchar_t *string, size_t maxlen)
+{
+	BOOL res;
+
+	res = HidD_GetIndexedString(dev->device_handle, string_index, string, sizeof(wchar_t) * MIN(maxlen, MAX_STRING_WCHARS));
+	if (!res) {
+		register_error(dev, "HidD_GetIndexedString");
+		return -1;
+	}
+
+	return 0;
+}
+
+
+HID_API_EXPORT const wchar_t * HID_API_CALL  hid_error(hid_device *dev)
+{
+	return (wchar_t*)dev->last_error_str;
+}
+
+
+/*#define PICPGM*/
+/*#define S11*/
+#define P32
+#ifdef S11 
+  unsigned short VendorID = 0xa0a0;
+	unsigned short ProductID = 0x0001;
+#endif
+
+#ifdef P32
+  unsigned short VendorID = 0x04d8;
+	unsigned short ProductID = 0x3f;
+#endif
+
+
+#ifdef PICPGM
+  unsigned short VendorID = 0x04d8;
+  unsigned short ProductID = 0x0033;
+#endif
+
+
+#if 0
+int __cdecl main(int argc, char* argv[])
+{
+	int res;
+	unsigned char buf[65];
+
+	UNREFERENCED_PARAMETER(argc);
+	UNREFERENCED_PARAMETER(argv);
+
+	/* Set up the command buffer. */
+	memset(buf,0x00,sizeof(buf));
+	buf[0] = 0;
+	buf[1] = 0x81;
+	
+
+	/* Open the device. */
+	int handle = open(VendorID, ProductID, L"12345");
+	if (handle < 0)
+		printf("unable to open device\n");
+
+
+	/* Toggle LED (cmd 0x80) */
+	buf[1] = 0x80;
+	res = write(handle, buf, 65);
+	if (res < 0)
+		printf("Unable to write()\n");
+
+	/* Request state (cmd 0x81) */
+	buf[1] = 0x81;
+	write(handle, buf, 65);
+	if (res < 0)
+		printf("Unable to write() (2)\n");
+
+	/* Read requested state */
+	read(handle, buf, 65);
+	if (res < 0)
+		printf("Unable to read()\n");
+
+	/* Print out the returned buffer. */
+	for (int i = 0; i < 4; i++)
+		printf("buf[%d]: %d\n", i, buf[i]);
+
+	return 0;
+}
+#endif
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/AUTHORS b/vendor/github.com/karalabe/hid/libusb/AUTHORS
index 70d407bd1..70d407bd1 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/AUTHORS
+++ b/vendor/github.com/karalabe/hid/libusb/AUTHORS
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/COPYING b/vendor/github.com/karalabe/hid/libusb/COPYING
index 5ab7695ab..5ab7695ab 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/COPYING
+++ b/vendor/github.com/karalabe/hid/libusb/COPYING
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/config.h b/vendor/github.com/karalabe/hid/libusb/libusb/config.h
index e004f03cd..e004f03cd 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/config.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/config.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/core.c b/vendor/github.com/karalabe/hid/libusb/libusb/core.c
index d45bfe177..d45bfe177 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/core.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/core.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/descriptor.c b/vendor/github.com/karalabe/hid/libusb/libusb/descriptor.c
index 4c9435fff..4c9435fff 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/descriptor.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/descriptor.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/hotplug.c b/vendor/github.com/karalabe/hid/libusb/libusb/hotplug.c
index bbfd6e79a..bbfd6e79a 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/hotplug.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/hotplug.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/hotplug.h b/vendor/github.com/karalabe/hid/libusb/libusb/hotplug.h
index 2bec81b06..2bec81b06 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/hotplug.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/hotplug.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/io.c b/vendor/github.com/karalabe/hid/libusb/libusb/io.c
index eb1eabf1c..eb1eabf1c 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/io.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/io.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/libusb.h b/vendor/github.com/karalabe/hid/libusb/libusb/libusb.h
index c562690f9..c562690f9 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/libusb.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/libusb.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/libusbi.h b/vendor/github.com/karalabe/hid/libusb/libusb/libusbi.h
index 752e39887..752e39887 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/libusbi.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/libusbi.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/darwin_usb.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/darwin_usb.c
index b0219d1b0..b0219d1b0 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/darwin_usb.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/darwin_usb.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/darwin_usb.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/darwin_usb.h
index 118043421..118043421 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/darwin_usb.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/darwin_usb.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_pollfs.cpp b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_pollfs.cpp
index e0c771320..e0c771320 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_pollfs.cpp
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_pollfs.cpp
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb.h
index d51ae9eae..d51ae9eae 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb_backend.cpp b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb_backend.cpp
index d3de8cc08..d3de8cc08 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb_backend.cpp
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb_backend.cpp
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb_raw.cpp b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb_raw.cpp
index 77adbd1e6..77adbd1e6 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb_raw.cpp
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb_raw.cpp
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb_raw.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb_raw.h
index 5baf53d7c..5baf53d7c 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/haiku_usb_raw.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/haiku_usb_raw.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_netlink.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_netlink.c
index 60cf3ad1b..60cf3ad1b 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_netlink.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_netlink.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_udev.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_udev.c
index 61d953d8c..61d953d8c 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_udev.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_udev.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_usbfs.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_usbfs.c
index 6b89ba288..6b89ba288 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_usbfs.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_usbfs.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_usbfs.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_usbfs.h
index 8bd3ebcb1..8bd3ebcb1 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/linux_usbfs.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/linux_usbfs.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/netbsd_usb.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/netbsd_usb.c
index ad1ede73e..ad1ede73e 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/netbsd_usb.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/netbsd_usb.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/openbsd_usb.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/openbsd_usb.c
index c66025711..c66025711 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/openbsd_usb.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/openbsd_usb.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_posix.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_posix.c
index e2f55a57a..e2f55a57a 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_posix.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_posix.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_posix.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_posix.h
index 5b4b2c905..5b4b2c905 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_posix.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_posix.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_windows.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.c
index 982560751..982560751 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_windows.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_windows.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.h
index aa4c985da..aa4c985da 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/poll_windows.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/poll_windows.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/sunos_usb.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/sunos_usb.c
index cb608976b..cb608976b 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/sunos_usb.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/sunos_usb.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/sunos_usb.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/sunos_usb.h
index 574166031..574166031 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/sunos_usb.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/sunos_usb.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_posix.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_posix.c
index a4f270bbe..a4f270bbe 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_posix.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_posix.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_posix.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_posix.h
index 4c1514ea6..4c1514ea6 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_posix.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_posix.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_windows.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_windows.c
index 7c2e52dba..7c2e52dba 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_windows.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_windows.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_windows.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_windows.h
index e97ee7875..e97ee7875 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/threads_windows.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/threads_windows.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/wince_usb.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/wince_usb.c
index 0d466b8c9..0d466b8c9 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/wince_usb.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/wince_usb.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/wince_usb.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/wince_usb.h
index edcb9fcc4..edcb9fcc4 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/wince_usb.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/wince_usb.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_common.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_common.h
index 55344ca26..55344ca26 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_common.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_common.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_nt_common.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_nt_common.c
index d935394a6..d935394a6 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_nt_common.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_nt_common.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_nt_common.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_nt_common.h
index 52ea8708b..52ea8708b 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_nt_common.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_nt_common.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_usbdk.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_usbdk.c
index 7cc579387..7cc579387 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_usbdk.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_usbdk.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_usbdk.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_usbdk.h
index 04a9787f2..04a9787f2 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_usbdk.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_usbdk.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_winusb.c b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_winusb.c
index 0dce0ea6c..0dce0ea6c 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_winusb.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_winusb.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_winusb.h b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_winusb.h
index b7b9cd919..b7b9cd919 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/os/windows_winusb.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/os/windows_winusb.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/strerror.c b/vendor/github.com/karalabe/hid/libusb/libusb/strerror.c
index d2be0e2a0..d2be0e2a0 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/strerror.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/strerror.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/sync.c b/vendor/github.com/karalabe/hid/libusb/libusb/sync.c
index a609f65f4..a609f65f4 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/sync.c
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/sync.c
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/version.h b/vendor/github.com/karalabe/hid/libusb/libusb/version.h
index 6ce48a7d0..6ce48a7d0 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/version.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/version.h
diff --git a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/version_nano.h b/vendor/github.com/karalabe/hid/libusb/libusb/version_nano.h
index 0a5d1c992..0a5d1c992 100644
--- a/vendor/github.com/karalabe/gousb/internal/libusb/libusb/version_nano.h
+++ b/vendor/github.com/karalabe/hid/libusb/libusb/version_nano.h
diff --git a/vendor/github.com/karalabe/hid/wchar.go b/vendor/github.com/karalabe/hid/wchar.go
new file mode 100644
index 000000000..d103beff5
--- /dev/null
+++ b/vendor/github.com/karalabe/hid/wchar.go
@@ -0,0 +1,227 @@
+// This file is https://github.com/orofarne/gowchar/blob/master/gowchar.go
+//
+// It was vendored inline to work around CGO limitations that don't allow C types
+// to directly cross package API boundaries.
+//
+// The vendored file is licensed under the 3-clause BSD license, according to:
+// https://github.com/orofarne/gowchar/blob/master/LICENSE
+
+// +build !ios
+// +build linux darwin windows
+
+package hid
+
+/*
+#include <wchar.h>
+
+const size_t SIZEOF_WCHAR_T = sizeof(wchar_t);
+
+void gowchar_set (wchar_t *arr, int pos, wchar_t val)
+{
+	arr[pos] = val;
+}
+
+wchar_t gowchar_get (wchar_t *arr, int pos)
+{
+	return arr[pos];
+}
+*/
+import "C"
+
+import (
+	"fmt"
+	"unicode/utf16"
+	"unicode/utf8"
+)
+
+var sizeofWcharT C.size_t = C.size_t(C.SIZEOF_WCHAR_T)
+
+func stringToWcharT(s string) (*C.wchar_t, C.size_t) {
+	switch sizeofWcharT {
+	case 2:
+		return stringToWchar2(s) // Windows
+	case 4:
+		return stringToWchar4(s) // Unix
+	default:
+		panic(fmt.Sprintf("Invalid sizeof(wchar_t) = %v", sizeofWcharT))
+	}
+}
+
+func wcharTToString(s *C.wchar_t) (string, error) {
+	switch sizeofWcharT {
+	case 2:
+		return wchar2ToString(s) // Windows
+	case 4:
+		return wchar4ToString(s) // Unix
+	default:
+		panic(fmt.Sprintf("Invalid sizeof(wchar_t) = %v", sizeofWcharT))
+	}
+}
+
+func wcharTNToString(s *C.wchar_t, size C.size_t) (string, error) {
+	switch sizeofWcharT {
+	case 2:
+		return wchar2NToString(s, size) // Windows
+	case 4:
+		return wchar4NToString(s, size) // Unix
+	default:
+		panic(fmt.Sprintf("Invalid sizeof(wchar_t) = %v", sizeofWcharT))
+	}
+}
+
+// Windows
+func stringToWchar2(s string) (*C.wchar_t, C.size_t) {
+	var slen int
+	s1 := s
+	for len(s1) > 0 {
+		r, size := utf8.DecodeRuneInString(s1)
+		if er, _ := utf16.EncodeRune(r); er == '\uFFFD' {
+			slen += 1
+		} else {
+			slen += 2
+		}
+		s1 = s1[size:]
+	}
+	slen++ // \0
+	res := C.malloc(C.size_t(slen) * sizeofWcharT)
+	var i int
+	for len(s) > 0 {
+		r, size := utf8.DecodeRuneInString(s)
+		if r1, r2 := utf16.EncodeRune(r); r1 != '\uFFFD' {
+			C.gowchar_set((*C.wchar_t)(res), C.int(i), C.wchar_t(r1))
+			i++
+			C.gowchar_set((*C.wchar_t)(res), C.int(i), C.wchar_t(r2))
+			i++
+		} else {
+			C.gowchar_set((*C.wchar_t)(res), C.int(i), C.wchar_t(r))
+			i++
+		}
+		s = s[size:]
+	}
+	C.gowchar_set((*C.wchar_t)(res), C.int(slen-1), C.wchar_t(0)) // \0
+	return (*C.wchar_t)(res), C.size_t(slen)
+}
+
+// Unix
+func stringToWchar4(s string) (*C.wchar_t, C.size_t) {
+	slen := utf8.RuneCountInString(s)
+	slen++ // \0
+	res := C.malloc(C.size_t(slen) * sizeofWcharT)
+	var i int
+	for len(s) > 0 {
+		r, size := utf8.DecodeRuneInString(s)
+		C.gowchar_set((*C.wchar_t)(res), C.int(i), C.wchar_t(r))
+		s = s[size:]
+		i++
+	}
+	C.gowchar_set((*C.wchar_t)(res), C.int(slen-1), C.wchar_t(0)) // \0
+	return (*C.wchar_t)(res), C.size_t(slen)
+}
+
+// Windows
+func wchar2ToString(s *C.wchar_t) (string, error) {
+	var i int
+	var res string
+	for {
+		ch := C.gowchar_get(s, C.int(i))
+		if ch == 0 {
+			break
+		}
+		r := rune(ch)
+		i++
+		if !utf16.IsSurrogate(r) {
+			if !utf8.ValidRune(r) {
+				err := fmt.Errorf("Invalid rune at position %v", i)
+				return "", err
+			}
+			res += string(r)
+		} else {
+			ch2 := C.gowchar_get(s, C.int(i))
+			r2 := rune(ch2)
+			r12 := utf16.DecodeRune(r, r2)
+			if r12 == '\uFFFD' {
+				err := fmt.Errorf("Invalid surrogate pair at position %v", i-1)
+				return "", err
+			}
+			res += string(r12)
+			i++
+		}
+	}
+	return res, nil
+}
+
+// Unix
+func wchar4ToString(s *C.wchar_t) (string, error) {
+	var i int
+	var res string
+	for {
+		ch := C.gowchar_get(s, C.int(i))
+		if ch == 0 {
+			break
+		}
+		r := rune(ch)
+		if !utf8.ValidRune(r) {
+			err := fmt.Errorf("Invalid rune at position %v", i)
+			return "", err
+		}
+		res += string(r)
+		i++
+	}
+	return res, nil
+}
+
+// Windows
+func wchar2NToString(s *C.wchar_t, size C.size_t) (string, error) {
+	var i int
+	var res string
+	N := int(size)
+	for i < N {
+		ch := C.gowchar_get(s, C.int(i))
+		if ch == 0 {
+			break
+		}
+		r := rune(ch)
+		i++
+		if !utf16.IsSurrogate(r) {
+			if !utf8.ValidRune(r) {
+				err := fmt.Errorf("Invalid rune at position %v", i)
+				return "", err
+			}
+
+			res += string(r)
+		} else {
+			if i >= N {
+				err := fmt.Errorf("Invalid surrogate pair at position %v", i-1)
+				return "", err
+			}
+			ch2 := C.gowchar_get(s, C.int(i))
+			r2 := rune(ch2)
+			r12 := utf16.DecodeRune(r, r2)
+			if r12 == '\uFFFD' {
+				err := fmt.Errorf("Invalid surrogate pair at position %v", i-1)
+				return "", err
+			}
+			res += string(r12)
+			i++
+		}
+	}
+	return res, nil
+}
+
+// Unix
+func wchar4NToString(s *C.wchar_t, size C.size_t) (string, error) {
+	var i int
+	var res string
+	N := int(size)
+	for i < N {
+		ch := C.gowchar_get(s, C.int(i))
+		r := rune(ch)
+		if !utf8.ValidRune(r) {
+			err := fmt.Errorf("Invalid rune at position %v", i)
+			return "", err
+		}
+		res += string(r)
+		i++
+	}
+	return res, nil
+}
diff --git a/vendor/vendor.json b/vendor/vendor.json
index f44f0038a..e19d011f1 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -119,10 +119,11 @@
 			"revisionTime": "2016-06-03T03:41:37Z"
 		},
 		{
-			"checksumSHA1": "SdiKy93Lsh3ly7I2E7vhlyp2Xq8=",
-			"path": "github.com/karalabe/gousb/usb",
-			"revision": "ffa821b2e25aa1828ffca731f759a1ebfa410d73",
-			"revisionTime": "2017-01-24T16:09:49Z"
+			"checksumSHA1": "HKy8oSpuboe02Uqq+43zbIzD/AY=",
+			"path": "github.com/karalabe/hid",
+			"revision": "40280bf4f6fc762010efeb066cbff7490d467f03",
+			"revisionTime": "2017-02-17T09:52:56Z",
+			"tree": true
 		},
 		{
 			"checksumSHA1": "7hln62oZPZmyqEmgXaybf9WxQ7A=",