1Link Layer Validation Device is a standard device for testing of Super 2Speed Link Layer tests. These nodes are available in sysfs only when lvs 3driver is bound with root hub device. 4 5What: /sys/bus/usb/devices/.../get_dev_desc 6Date: March 2014 7Contact: Pratyush Anand <pratyush.anand@gmail.com> 8Description: 9 Write to this node to issue "Get Device Descriptor" 10 for Link Layer Validation device. It is needed for TD.7.06. 11 12What: /sys/bus/usb/devices/.../u1_timeout 13Date: March 2014 14Contact: Pratyush Anand <pratyush.anand@gmail.com> 15Description: 16 Set "U1 timeout" for the downstream port where Link Layer 17 Validation device is connected. Timeout value must be between 0 18 and 127. It is needed for TD.7.18, TD.7.19, TD.7.20 and TD.7.21. 19 20What: /sys/bus/usb/devices/.../u2_timeout 21Date: March 2014 22Contact: Pratyush Anand <pratyush.anand@gmail.com> 23Description: 24 Set "U2 timeout" for the downstream port where Link Layer 25 Validation device is connected. Timeout value must be between 0 26 and 127. It is needed for TD.7.18, TD.7.19, TD.7.20 and TD.7.21. 27 28What: /sys/bus/usb/devices/.../hot_reset 29Date: March 2014 30Contact: Pratyush Anand <pratyush.anand@gmail.com> 31Description: 32 Write to this node to issue "Reset" for Link Layer Validation 33 device. It is needed for TD.7.29, TD.7.31, TD.7.34 and TD.7.35. 34 35What: /sys/bus/usb/devices/.../u3_entry 36Date: March 2014 37Contact: Pratyush Anand <pratyush.anand@gmail.com> 38Description: 39 Write to this node to issue "U3 entry" for Link Layer 40 Validation device. It is needed for TD.7.35 and TD.7.36. 41 42What: /sys/bus/usb/devices/.../u3_exit 43Date: March 2014 44Contact: Pratyush Anand <pratyush.anand@gmail.com> 45Description: 46 Write to this node to issue "U3 exit" for Link Layer 47 Validation device. It is needed for TD.7.36. 48 49What: /sys/bus/usb/devices/.../enable_compliance 50Date: July 2017 51Description: 52 Write to this node to set the port to compliance mode to test 53 with Link Layer Validation device. It is needed for TD.7.34. 54 55What: /sys/bus/usb/devices/.../warm_reset 56Date: July 2017 57Description: 58 Write to this node to issue "Warm Reset" for Link Layer Validation 59 device. It may be needed to properly reset an xHCI 1.1 host port if 60 compliance mode needed to be explicitly enabled. 61