Link Layer Validation Device is a standard device for testing of Super
Speed Link Layer tests. These nodes are available in sysfs only when lvs
driver is bound with root hub device.

What:		/sys/bus/usb/devices/.../get_dev_desc
Date:		March 2014
Contact:	Pratyush Anand <pratyush.anand@gmail.com>
Description:
		Write to this node to issue "Get Device Descriptor"
		for Link Layer Validation device. It is needed for TD.7.06.

What:		/sys/bus/usb/devices/.../u1_timeout
Date:		March 2014
Contact:	Pratyush Anand <pratyush.anand@gmail.com>
Description:
		Set "U1 timeout" for the downstream port where Link Layer
		Validation device is connected. Timeout value must be between 0
		and 127. It is needed for TD.7.18, TD.7.19, TD.7.20 and TD.7.21.

What:		/sys/bus/usb/devices/.../u2_timeout
Date:		March 2014
Contact:	Pratyush Anand <pratyush.anand@gmail.com>
Description:
		Set "U2 timeout" for the downstream port where Link Layer
		Validation device is connected. Timeout value must be between 0
		and 127. It is needed for TD.7.18, TD.7.19, TD.7.20 and TD.7.21.

What:		/sys/bus/usb/devices/.../hot_reset
Date:		March 2014
Contact:	Pratyush Anand <pratyush.anand@gmail.com>
Description:
		Write to this node to issue "Reset" for Link Layer Validation
		device. It is needed for TD.7.29, TD.7.31, TD.7.34 and TD.7.35.

What:		/sys/bus/usb/devices/.../u3_entry
Date:		March 2014
Contact:	Pratyush Anand <pratyush.anand@gmail.com>
Description:
		Write to this node to issue "U3 entry" for Link Layer
		Validation device. It is needed for TD.7.35 and TD.7.36.

What:		/sys/bus/usb/devices/.../u3_exit
Date:		March 2014
Contact:	Pratyush Anand <pratyush.anand@gmail.com>
Description:
		Write to this node to issue "U3 exit" for Link Layer
		Validation device. It is needed for TD.7.36.