wiki:windows_backend

Version 38 (modified by pbatard, 3 years ago) (diff)

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Windows backend

About

The aim of this project is to bring a Windows backend to the mainline libusb 1.0 branch, so that libusb 1.0 can easily be used on Windows platforms.

Status

The Windows backend is now in pre-release stages. As of 2010.02.17, it include all of the main libusb v1.0 features, for both HID and WinUSB devices, apart from isochronous transfers (which is a limitation from the WinUSB Microsoft API).
It currently supports all Windows platforms from Windows XP, including 64 bit versions of Windows (Windows 2003 is untested).

Source

The current development Windows backend is available in the ​libusb main git repository under ​libusb-pbatard.git.

For those not familiar with git, here are the git commands you can use retrieve and compile the Windows branch: 

git clone git://git.libusb.org/libusb-pbatard.git ; retrieve development branch (this only needs to be done once)
git pull                                          ; keep in sync with the remote tree

On Windows, if you don't want to use git on the commandline, you can use ​TortoiseGit to access and keep in sync with the git repository.
Note that before you can install ​TortoiseGit you need to install ​MSysGit and make sure that, during the installation of MSysGit, when prompted to adjust the PATH environment, you select "Run Git from the Windows Command Prompt" (2nd option). Also, in the general settings of ​TortoiseGit, the MSysGit path must point to the MSysGit bin directory (eg: C:Program Files (x86)Gitin")

Also note that, for MinGW and cygwin, as per the official libusb 1.0 project, you need to run './autogen.sh' in order to have configure and Makefile created for you.

The following development environment are currently supported for libusb 1.0 on Windows:

To create projects relying on libusb 1.0, please refer to how the executables are compiled for the various environments above.

Finally, to access your USB devices with libusb-winusb, you need to download the ​WinUSB driver files, customize the .inf for your device, and then install the driver.
For more information on how to setup the WinUSB driver for your device, please see the WinUSB Driver Installation page or see the README file that comes with the driver.

Note: If you have downloaded a development version prior to r169, you will also need ​pthread-win32 to compile this source (except on cygwin). Note that the version of the DLL to use then is VC2, not GC
For convenience, precompiled versions of pthread-win32 for 32 bit and 64 bit Windows platforms are provided ​here. If you are unfamiliar with pthread to use, please download this archive.
The requirement for pthread-win32 has been removed from development version r169 and later, so, whenever possible, please ensure you use the latest source.

Development Considerations

  • For the first release, only ​WinUSB and HID access will be supported, with provisions for other access modes to be included later. This should cover most devices however.
  • Windows' handling of composite devices is done with multiple drivers (VID_####&PID_####&MI_##), descendants of the usbccgp.sys driver (Composite Generic Parent). For more info, see "2. How Windows handles a composite device" at ​http://www.cygnal.org/ubb/Forum9/HTML/001050.html.
  • Because Windows does not provide a native poll() function, and cygwin is the only development environment that provides such a call, the use of libusb file descriptors with poll() on cygwin is NOT supported. If you do need to manually poll the libusb file descriptors on Windows, you can use the undocumented _libusb_poll() function (same parameters as poll() from UNIX), but please note that the function will only accept libusb file descriptors and it is not possible to _libusb_poll() to poll for generic file descriptors. We might provide native Windows Event to wait on in a future version of libusb for Windows.

Known Restrictions

  • IOCTL_USB_GET_NODE_CONNECTION_INFORMATION ​appears to be broken in MinGW-w64 (x64 platforms).
  • WinUSB does not support multiple concurrent applications (as per the ​WinUSB Howto whitepaper).
  • WinUSB does not support isochronous transfers.
  • Windows does not allow read or write access to HID keyboards and mice
  • Windows does not allow generic USB access to HID devices or interfaces for which the OS has a specific, non generic driver (eg. HID audio devices)

To Do

  • automated WinUSB driver installation
  • hotplug detection

Done

  • full pthread-win32 dependency removal
  • multithreading/concurrent access
  • HID
  • device enumeration
  • descriptors retrieval
  • composite devices & interface selection
  • poll and pipe
  • control transfers
  • bulk/interrupt transfers
  • device reset
  • transfer cancellation
  • MSVC compatibility

Development's status log

  • [2010.01.14 and later] Please consult the ​git log or the raw Activity Log.
  • [2009.12.13 to 2010.01.13] Tracked on the the ​Work-In-Progress SVN Repository (no longer maintained).
  • [2009.12.12]
    • Back on track after resubmission of git patches and timer related fixes.
  • [2009.12.04]
  • [2009.12.03]
    • matching of libusb enumerated devices with WinUSB GUID devices (WIP)
    • ​WinUSB driver cleanup & documentation.
  • [2009.12.02]
    • WinUSB generic device installation (x86 & x64)
    • retrieval of device handles for use with WinUSB
    • WinUSB init
  • [2009.12.01]
    • configuration descriptors retrieval
    • initial possible API breakdown & more code cleanup
  • [2009.11.30]
    • Added clock_gettime() with hires timer detection for monotonic and GetSystemTimeAsFileTime?() (100 ns resolution) for realtime.
    • Moved the USB 2.0 root hub caps detection into set_hcd_device_descriptor()
  • [2009.11.29]
    • First release with working lsusb enumeration

Mailing list

The libusb-devel mailing list exists for the users of the library, plus developers interested in contributing to the library itself.

Attachments

Download all attachments as: .zip