USB Stack
The USB stack is the component that provides the communication between USB devices and their respective drivers and applications. It consists of multiple files, each with a distinct function. The USB stack in ReactOS is currently limited. This page documents the development of the new USB stack. Development work on a USB 3 stack is in progress.
Warning: With current versions of ReactOS, USB support is NOT advanced enough to successfully work with complex USB devices such as web-cameras, sound cards and etc. Please mind that system may crash due problem caused by such USB-device. If possible, it is better to avoid using USB devices together with ReactOS, unless this is the main purpose of your experiment.
NOTE: There is a known issue with booting ReactOS from the internal HDD with a USB storage device connected which causes ROS to lose the boot device. Until this problem is fixed or a workaround is developed, please unplug any USB storage devices during boot!
Contents
Overview
The goal is to develop a USB stack which:
- is USB 1.1 – 2.0 compliant
- uses WDM (NT 5) API
- is compatible with all USB devices and drivers (which adhere to the standard)
The entire stack will be fully documented and the implementation progress detailed on this page.
Goals
- Primary Goal: USBHID (human input devices) and storage functionality working (Alpha).
- Secondary Goal: Audio and other support added.
- Beyond: testing and debugging.
Due to the complexity and size, no release dates will be provided as of now.
Status
USB Core Status
- There are 2 USB specifications for the USB 1.1 standard. Devices that are used in this standard are mice, keyboards, etc.
- OHCI (Open Host Controller Interface Standard) – All transfers types are implemented (bulk, iso, control, interrupt)
- UHCI (Universal Host Controller Interface Standard) – Totally missing. Though it should be do-able to use OHCI driver as a base and use Haiku driver
- EHCI (Enhanced Host Controller Interface) – Implemented transfer types: bulk & control. Interrupt & Isochronous transfers are not implemented. Due to the missing transfer types, devices who utilize those transfer types will not be available.
- USBHUB – driver for managing port and hubs – Implementation state is unknown – Michel Martin has more information on that
USB Mass Storage Support Status
USB Mass Storage is implemented in USBSTOR driver and is fully working. Tested in WinXP + USBEHCI + USBSTOR. Mass storage support requires bulk and control transfers, which are implemented in USBEHCI.
HID Status
The HID framework is built on 5 drivers
- HIDUSB – this is the interface driver for the USB bus. Currently supported devices are mice. Basic keyboard support should also work currently.
- HIDCLASS – this is the class driver for HIDUSB and others. Functionality for mice & keyboard is implemented, though support for sending output reports is not implemented.
- MOUHID – mouse function driver for USB hid standard – Fully implemented and working.
- KBDHID – keyboard function driver for the hid standard – 90% implemented, needs KbdHid_InsertScanCodes implemented for keyboard scan code dispatching to kbdclass and led status indicator support (which requires sending output reports).
- HIDPARSE – driver for parsing report descriptors – functionality implemented for mice, keyboard support needs HidParser_TranslateUsage fully implemented for modifier state (caps lock, num lock, scroll lock).
What already works
- Mouse support has been tested in WinXP with ReactOS USBOHCI + HIDUSB + HIDCLASS + MOUHID + HIDPARSE and is working. The USB + HID stack also works in ReactOS.
- Basic Keyboard support is nearly ready.
- USB Mass storage support – Needs mountmgr / partmgr driver implemented. Will also need mountvol and other missing PnP stuff. - needs a few more issues to be resolved
See Also
Links
- History of USB in ReactOS April 9th, 2009
- More news about USB April 22nd, 2010
- New USB Drivers April 28th, 2011
- Two of Four host controller interface drivers completed January 23rd, 2012
- USB Working January 26, 2012
- USB branch merged at r55555 February 12th, 2012
- USB branch merged with trunk February 28th, 2012
References
- USB.org specifications
- XEN PV USB Drivers
- Roadmap for Developing USB Drivers (Archived)
- Windows Driver Kit (Driver Development Kit)
- USB Driver Stack for Windows XP and later (Archived)
- USB Device Stack for Windows XP and later (Archived)
- USB 3.0 xHCI specifications