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-rw-r--r--Documentation/ABI/testing/sysfs-bus-usb27
1 files changed, 20 insertions, 7 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index 3a4abfc44f5e..0bd731cbb50c 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -134,19 +134,21 @@ Description:
enabled for the device. Developer can write y/Y/1 or n/N/0 to
the file to enable/disable the feature.
-What: /sys/bus/usb/devices/.../power/usb3_hardware_lpm
-Date: June 2015
+What: /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u1
+ /sys/bus/usb/devices/.../power/usb3_hardware_lpm_u2
+Date: November 2015
Contact: Kevin Strasser <kevin.strasser@linux.intel.com>
+ Lu Baolu <baolu.lu@linux.intel.com>
Description:
If CONFIG_PM is set and a USB 3.0 lpm-capable device is plugged
in to a xHCI host which supports link PM, it will check if U1
and U2 exit latencies have been set in the BOS descriptor; if
- the check is is passed and the host supports USB3 hardware LPM,
+ the check is passed and the host supports USB3 hardware LPM,
USB3 hardware LPM will be enabled for the device and the USB
- device directory will contain a file named
- power/usb3_hardware_lpm. The file holds a string value (enable
- or disable) indicating whether or not USB3 hardware LPM is
- enabled for the device.
+ device directory will contain two files named
+ power/usb3_hardware_lpm_u1 and power/usb3_hardware_lpm_u2. These
+ files hold a string value (enable or disable) indicating whether
+ or not USB3 hardware LPM U1 or U2 is enabled for the device.
What: /sys/bus/usb/devices/.../removable
Date: February 2012
@@ -187,6 +189,17 @@ Description:
The file will read "hotplug", "wired" and "not used" if the
information is available, and "unknown" otherwise.
+What: /sys/bus/usb/devices/.../(hub interface)/portX/usb3_lpm_permit
+Date: November 2015
+Contact: Lu Baolu <baolu.lu@linux.intel.com>
+Description:
+ Some USB3.0 devices are not friendly to USB3 LPM. usb3_lpm_permit
+ attribute allows enabling/disabling usb3 lpm of a port. It takes
+ effect both before and after a usb device is enumerated. Supported
+ values are "0" if both u1 and u2 are NOT permitted, "u1" if only u1
+ is permitted, "u2" if only u2 is permitted, "u1_u2" if both u1 and
+ u2 are permitted.
+
What: /sys/bus/usb/devices/.../power/usb2_lpm_l1_timeout
Date: May 2013
Contact: Mathias Nyman <mathias.nyman@linux.intel.com>