2007-03-13 16:39:15 -04:00
										 
									 
								 
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							 | 
							
								
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								What:		/sys/bus/usb/devices/.../power/autosuspend
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								Date:		March 2007
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								KernelVersion:	2.6.21
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								Contact:	Alan Stern <stern@rowland.harvard.edu>
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							| 
								
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								Description:
							 | 
						
					
						
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							 | 
							
							
										Each USB device directory will contain a file named
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										power/autosuspend.  This file holds the time (in seconds)
							 | 
						
					
						
							| 
								
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							 | 
							
								
							 | 
							
							
										the device must be idle before it will be autosuspended.
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							 | 
							
							
										0 means the device will be autosuspended as soon as
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										possible.  Negative values will prevent the device from
							 | 
						
					
						
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							 | 
							
							
										being autosuspended at all, and writing a negative value
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										will resume the device if it is already suspended.
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										The autosuspend delay for newly-created devices is set to
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							 | 
							
							
										the value of the usbcore.autosuspend module parameter.
							 | 
						
					
						
							
								
									
										
										
										
											2007-03-20 14:59:39 -04:00
										 
									 
								 
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											2007-05-30 15:39:33 -04:00
										 
									 
								 
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								What:		/sys/bus/usb/devices/.../power/persist
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								Date:		May 2007
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								KernelVersion:	2.6.23
							 | 
						
					
						
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								Contact:	Alan Stern <stern@rowland.harvard.edu>
							 | 
						
					
						
							| 
								
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								Description:
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							 | 
							
							
										If CONFIG_USB_PERSIST is set, then each USB device directory
							 | 
						
					
						
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										will contain a file named power/persist.  The file holds a
							 | 
						
					
						
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							 | 
							
								
							 | 
							
								
							 | 
							
							
										boolean value (0 or 1) indicating whether or not the
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										"USB-Persist" facility is enabled for the device.  Since the
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							 | 
							
							
										facility is inherently dangerous, it is disabled by default
							 | 
						
					
						
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							 | 
							
							
										for all devices except hubs.  For more information, see
							 | 
						
					
						
							| 
								
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							 | 
							
								
							 | 
							
							
										Documentation/usb/persist.txt.
							 | 
						
					
						
							
								
									
										
										
										
											2008-01-17 10:24:38 -08:00
										 
									 
								 
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								What:		/sys/bus/usb/device/.../power/connected_duration
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								Date:		January 2008
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								KernelVersion:	2.6.25
							 | 
						
					
						
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							 | 
							
							
								Contact:	Sarah Sharp <sarah.a.sharp@intel.com>
							 | 
						
					
						
							| 
								
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								Description:
							 | 
						
					
						
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							 | 
							
							
										If CONFIG_PM and CONFIG_USB_SUSPEND are enabled, then this file
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										is present.  When read, it returns the total time (in msec)
							 | 
						
					
						
							| 
								
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							 | 
							
								
							 | 
							
							
										that the USB device has been connected to the machine.  This
							 | 
						
					
						
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							 | 
							
							
										file is read-only.
							 | 
						
					
						
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							 | 
							
							
								Users:
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										PowerTOP <power@bughost.org>
							 | 
						
					
						
							| 
								
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							 | 
							
								
							 | 
							
							
										http://www.lesswatts.org/projects/powertop/
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								What:		/sys/bus/usb/device/.../power/active_duration
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								Date:		January 2008
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								KernelVersion:	2.6.25
							 | 
						
					
						
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							 | 
							
							
								Contact:	Sarah Sharp <sarah.a.sharp@intel.com>
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							| 
								
							 | 
							
								
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							 | 
							
							
								Description:
							 | 
						
					
						
							| 
								
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							 | 
							
								
							 | 
							
							
										If CONFIG_PM and CONFIG_USB_SUSPEND are enabled, then this file
							 | 
						
					
						
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							 | 
							
								
							 | 
							
								
							 | 
							
							
										is present.  When read, it returns the total time (in msec)
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										that the USB device has been active, i.e. not in a suspended
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							 | 
							
							
										state.  This file is read-only.
							 | 
						
					
						
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										Tools can use this file and the connected_duration file to
							 | 
						
					
						
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							 | 
							
							
										compute the percentage of time that a device has been active.
							 | 
						
					
						
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										For example,
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										echo $((100 * `cat active_duration` / `cat connected_duration`))
							 | 
						
					
						
							| 
								
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							 | 
							
								
							 | 
							
							
										will give an integer percentage.  Note that this does not
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							 | 
							
							
										account for counter wrap.
							 | 
						
					
						
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								Users:
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										PowerTOP <power@bughost.org>
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							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										http://www.lesswatts.org/projects/powertop/
							 | 
						
					
						
							
								
									
										
										
										
											2008-09-17 16:34:41 +01:00
										 
									 
								 
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											2008-10-06 14:45:46 -07:00
										 
									 
								 
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								What:		/sys/bus/usb/device/<busnum>-<devnum>...:<config num>-<interface num>/supports_autosuspend
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								Date:		January 2008
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								KernelVersion:	2.6.27
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							 | 
							
							
								Contact:	Sarah Sharp <sarah.a.sharp@intel.com>
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							| 
								
							 | 
							
								
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							 | 
							
							
								Description:
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							 | 
							
							
										When read, this file returns 1 if the interface driver
							 | 
						
					
						
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							 | 
							
								
							 | 
							
								
							 | 
							
							
										for this interface supports autosuspend.  It also
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							 | 
							
							
										returns 1 if no driver has claimed this interface, as an
							 | 
						
					
						
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							 | 
							
							
										unclaimed interface will not stop the device from being
							 | 
						
					
						
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							 | 
							
							
										autosuspended if all other interface drivers are idle.
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										The file returns 0 if autosuspend support has not been
							 | 
						
					
						
							| 
								
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							 | 
							
								
							 | 
							
							
										added to the driver.
							 | 
						
					
						
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								Users:
							 | 
						
					
						
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										USB PM tool
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										git://git.moblin.org/users/sarah/usb-pm-tool/
							 | 
						
					
						
							
								
									
										
										
										
											2008-10-20 16:07:19 +01:00
										 
									 
								 
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											2008-09-17 16:34:41 +01:00
										 
									 
								 
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								What:		/sys/bus/usb/device/.../authorized
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								Date:		July 2008
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								KernelVersion:	2.6.26
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								Contact:	David Vrabel <david.vrabel@csr.com>
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								Description:
							 | 
						
					
						
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										Authorized devices are available for use by device
							 | 
						
					
						
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							 | 
							
							
										drivers, non-authorized one are not.  By default, wired
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							 | 
							
							
										USB devices are authorized.
							 | 
						
					
						
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										Certified Wireless USB devices are not authorized
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										initially and should be (by writing 1) after the
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										device has been authenticated.
							 | 
						
					
						
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								What:		/sys/bus/usb/device/.../wusb_cdid
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								Date:		July 2008
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								KernelVersion:	2.6.27
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								Contact:	David Vrabel <david.vrabel@csr.com>
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								Description:
							 | 
						
					
						
							| 
								
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							 | 
							
							
										For Certified Wireless USB devices only.
							 | 
						
					
						
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										A devices's CDID, as 16 space-separated hex octets.
							 | 
						
					
						
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								What:		/sys/bus/usb/device/.../wusb_ck
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								Date:		July 2008
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								KernelVersion:	2.6.27
							 | 
						
					
						
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								Contact:	David Vrabel <david.vrabel@csr.com>
							 | 
						
					
						
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								Description:
							 | 
						
					
						
							| 
								
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							 | 
							
							
										For Certified Wireless USB devices only.
							 | 
						
					
						
							| 
								
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										Write the device's connection key (CK) to start the
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										authentication of the device.  The CK is 16
							 | 
						
					
						
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							 | 
							
								
							 | 
							
								
							 | 
							
							
										space-separated hex octets.
							 | 
						
					
						
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								What:		/sys/bus/usb/device/.../wusb_disconnect
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								Date:		July 2008
							 | 
						
					
						
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								KernelVersion:	2.6.27
							 | 
						
					
						
							| 
								
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								Contact:	David Vrabel <david.vrabel@csr.com>
							 | 
						
					
						
							| 
								
							 | 
							
								
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							 | 
							
							
								Description:
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										For Certified Wireless USB devices only.
							 | 
						
					
						
							| 
								
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										Write a 1 to force the device to disconnect
							 | 
						
					
						
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							 | 
							
								
							 | 
							
							
										(equivalent to unplugging a wired USB device).
							 | 
						
					
						
							
								
									
										
										
										
											2009-11-22 01:28:52 +08:00
										 
									 
								 
							 | 
							
								
									
										
									
								
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											2011-10-23 14:22:29 +02:00
										 
									 
								 
							 | 
							
								
									
										
									
								
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								What:		/sys/bus/usb/drivers/.../new_id
							 | 
						
					
						
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								Date:		October 2011
							 | 
						
					
						
							| 
								
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								Contact:	linux-usb@vger.kernel.org
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								Description:
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										Writing a device ID to this file will attempt to
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										dynamically add a new device ID to a USB device driver.
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										This may allow the driver to support more hardware than
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										was included in the driver's static device ID support
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										table at compile time. The format for the device ID is:
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										idVendor idProduct bInterfaceClass.
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										The vendor ID and device ID fields are required, the
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										interface class is optional.
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										Upon successfully adding an ID, the driver will probe
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										for the device and attempt to bind to it.  For example:
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										# echo "8086 10f5" > /sys/bus/usb/drivers/foo/new_id
							 | 
						
					
						
							| 
								
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							 | 
							
							
								
							 | 
						
					
						
							| 
								
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								What:		/sys/bus/usb-serial/drivers/.../new_id
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								Date:		October 2011
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								Contact:	linux-usb@vger.kernel.org
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
								Description:
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										For serial USB drivers, this attribute appears under the
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										extra bus folder "usb-serial" in sysfs; apart from that
							 | 
						
					
						
							| 
								
							 | 
							
								
							 | 
							
								
							 | 
							
							
										difference, all descriptions from the entry
							 | 
						
					
						
							| 
								
							 | 
							
								
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										"/sys/bus/usb/drivers/.../new_id" apply.
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											2009-11-22 01:28:52 +08:00
										 
									 
								 
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								What:		/sys/bus/usb/drivers/.../remove_id
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								Date:		November 2009
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								Contact:	CHENG Renquan <rqcheng@smu.edu.sg>
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								Description:
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										Writing a device ID to this file will remove an ID
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										that was dynamically added via the new_id sysfs entry.
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										The format for the device ID is:
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										idVendor idProduct.	After successfully
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										removing an ID, the driver will no longer support the
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										device.  This is useful to ensure auto probing won't
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										match the driver to the device.  For example:
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										# echo "046d c315" > /sys/bus/usb/drivers/foo/remove_id
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											2010-01-16 01:33:03 +01:00
										 
									 
								 
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											2010-03-12 11:27:21 +01:00
										 
									 
								 
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								What:		/sys/bus/usb/device/.../avoid_reset_quirk
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											2010-01-16 01:33:03 +01:00
										 
									 
								 
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								Date:		December 2009
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								Contact:	Oliver Neukum <oliver@neukum.org>
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								Description:
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										Writing 1 to this file tells the kernel that this
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										device will morph into another mode when it is reset.
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										Drivers will not use reset for error handling for
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										such devices.
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								Users:
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										usb_modeswitch
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											2011-09-23 14:19:53 -07:00
										 
									 
								 
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								What:		/sys/bus/usb/devices/.../power/usb2_hardware_lpm
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								Date:		September 2011
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								Contact:	Andiry Xu <andiry.xu@amd.com>
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								Description:
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										If CONFIG_USB_SUSPEND is set and a USB 2.0 lpm-capable device
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										is plugged in to a xHCI host which support link PM, it will
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										perform a LPM test; if the test is passed and host supports
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										USB2 hardware LPM (xHCI 1.0 feature), USB2 hardware LPM will
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										be enabled for the device and the USB device directory will
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										contain a file named power/usb2_hardware_lpm.  The file holds
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										a string value (enable or disable) indicating whether or not
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										USB2 hardware LPM is enabled for the device. Developer can
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										write y/Y/1 or n/N/0 to the file to enable/disable the
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										feature.
							 |