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
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										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:
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										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).
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											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:
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										Writing a device ID to this file will attempt to
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										dynamically add a new device ID to a USB device driver.
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										This may allow the driver to support more hardware than
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										was included in the driver's static device ID support
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										table at compile time. The format for the device ID is:
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										idVendor idProduct bInterfaceClass.
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										The vendor ID and device ID fields are required, the
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										interface class is optional.
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										Upon successfully adding an ID, the driver will probe
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										for the device and attempt to bind to it.  For example:
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										# echo "8086 10f5" > /sys/bus/usb/drivers/foo/new_id
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											2012-05-13 12:34:59 +02:00
										 
									 
								 
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										Reading from this file will list all dynamically added
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										device IDs in the same format, with one entry per
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										line. For example:
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										# cat /sys/bus/usb/drivers/foo/new_id
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										8086 10f5
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										dead beef 06
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										f00d cafe
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										The list will be truncated at PAGE_SIZE bytes due to
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										sysfs restrictions.
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											2011-10-23 14:22:29 +02:00
										 
									 
								 
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								What:		/sys/bus/usb-serial/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:
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										For serial USB drivers, this attribute appears under the
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										extra bus folder "usb-serial" in sysfs; apart from that
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										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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											2012-05-13 12:34:59 +02:00
										 
									 
								 
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										Reading from this file will list the dynamically added
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										device IDs, exactly like reading from the entry
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										"/sys/bus/usb/drivers/.../new_id"
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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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											2013-03-28 15:31:13 -04:00
										 
									 
								 
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										If CONFIG_PM_RUNTIME is set and a USB 2.0 lpm-capable device
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											2011-09-23 14:19:53 -07:00
										 
									 
								 
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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.
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											2012-02-03 17:11:54 -05:00
										 
									 
								 
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								What:		/sys/bus/usb/devices/.../removable
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								Date:		February 2012
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								Contact:	Matthew Garrett <mjg@redhat.com>
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								Description:
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										Some information about whether a given USB device is
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										physically fixed to the platform can be inferred from a
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											2012-04-10 00:22:13 +09:00
										 
									 
								 
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										combination of hub descriptor bits and platform-specific data
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											2012-02-03 17:11:54 -05:00
										 
									 
								 
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										such as ACPI. This file will read either "removable" or
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										"fixed" if the information is available, and "unknown"
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											2012-04-10 00:22:13 +09:00
										 
									 
								 
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										otherwise.
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											2012-07-05 17:17:24 -07:00
										 
									 
								 
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								What:		/sys/bus/usb/devices/.../ltm_capable
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								Date:		July 2012
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								Contact:	Sarah Sharp <sarah.a.sharp@linux.intel.com>
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								Description:
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										USB 3.0 devices may optionally support Latency Tolerance
							 | 
						
					
						
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										Messaging (LTM).  They indicate their support by setting a bit
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										in the bmAttributes field of their SuperSpeed BOS descriptors.
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										If that bit is set for the device, ltm_capable will read "yes".
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										If the device doesn't support LTM, the file will read "no".
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										The file will be present for all speeds of USB devices, and will
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							 | 
							
							
										always read "no" for USB 1.1 and USB 2.0 devices.
							 | 
						
					
						
							
								
									
										
										
										
											2012-09-05 13:44:31 +08:00
										 
									 
								 
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								What:		/sys/bus/usb/devices/.../(hub interface)/portX
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								Date:		August 2012
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							 | 
							
							
								Contact:	Lan Tianyu <tianyu.lan@intel.com>
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								Description:
							 | 
						
					
						
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										The /sys/bus/usb/devices/.../(hub interface)/portX
							 | 
						
					
						
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										is usb port device's sysfs directory.
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											2013-01-20 01:53:32 +08:00
										 
									 
								 
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								What:		/sys/bus/usb/devices/.../(hub interface)/portX/connect_type
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								Date:		January 2013
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								Contact:	Lan Tianyu <tianyu.lan@intel.com>
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								Description:
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										Some platforms provide usb port connect types through ACPI.
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										This attribute is to expose these information to user space.
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										The file will read "hotplug", "wired" and "not used" if the
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										information is available, and "unknown" otherwise.
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											2013-05-23 17:14:31 +03:00
										 
									 
								 
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								What:		/sys/bus/usb/devices/.../power/usb2_lpm_l1_timeout
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								Date:		May 2013
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								Contact:	Mathias Nyman <mathias.nyman@linux.intel.com>
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								Description:
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										USB 2.0 devices may support hardware link power management (LPM)
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										L1 sleep state. The usb2_lpm_l1_timeout attribute allows
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										tuning the timeout for L1 inactivity timer (LPM timer), e.g.
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										needed inactivity time before host requests the device to go to L1 sleep.
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										Useful for power management tuning.
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										Supported values are 0 - 65535 microseconds.
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								What:		/sys/bus/usb/devices/.../power/usb2_lpm_besl
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								Date:		May 2013
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								Contact:	Mathias Nyman <mathias.nyman@linux.intel.com>
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								Description:
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										USB 2.0 devices that support hardware link power management (LPM)
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										L1 sleep state now use a best effort service latency value (BESL) to
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										indicate the best effort to resumption of service to the device after the
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										initiation of the resume event.
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										If the device does not have a preferred besl value then the host can select
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										one instead. This usb2_lpm_besl attribute allows to tune the host selected besl
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										value in order to tune power saving and service latency.
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										Supported values are 0 - 15.
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										More information on how besl values map to microseconds can be found in
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										USB 2.0 ECN Errata for Link Power Management, section 4.10)
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