From 655fe4effe0f1f40e4f6ca6b3cc64a7fe0032183 Mon Sep 17 00:00:00 2001 From: Kevin Strasser Date: Tue, 16 Jun 2015 10:35:30 -0700 Subject: usbcore: add sysfs support to xHCI usb3 hardware LPM Add a sysfs node to make it easier to verify if LPM is supported and being enabled for USB 3.0 devices. Signed-off-by: Kevin Strasser Signed-off-by: Greg Kroah-Hartman --- Documentation/ABI/testing/sysfs-bus-usb | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'Documentation/ABI/testing/sysfs-bus-usb') diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb index e5cc7633d013..e935625f5995 100644 --- a/Documentation/ABI/testing/sysfs-bus-usb +++ b/Documentation/ABI/testing/sysfs-bus-usb @@ -114,6 +114,20 @@ 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 +Contact: Kevin Strasser +Description: + If CONFIG_PM_RUNTIME 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, 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. + What: /sys/bus/usb/devices/.../removable Date: February 2012 Contact: Matthew Garrett -- cgit v1.2.3