Merge branch 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel...

[sfrench/cifs-2.6.git] / Documentation / ABI / testing / sysfs-class-led

diff --git a/Documentation/ABI/testing/sysfs-class-led b/Documentation/ABI/testing/sysfs-class-led
index 491cdeedc195041a7f611f10490cc4ca569aeb9a..5f67f7ab277bc51af0bdb8ccb94ae03f6936ad6c 100644 (file)
--- a/Documentation/ABI/testing/sysfs-class-led
+++ b/Documentation/ABI/testing/sysfs-class-led
@@ -23,6 +23,23 @@ Description:
                If the LED does not support different brightness levels, this
                should be 1.
 
+What:          /sys/class/leds/<led>/brightness_hw_changed
+Date:          January 2017
+KernelVersion: 4.11
+Description:
+               Last hardware set brightness level for this LED. Some LEDs
+               may be changed autonomously by hardware/firmware. Only LEDs
+               where this happens and the driver can detect this, will have
+               this file.
+
+               This file supports poll() to detect when the hardware changes
+               the brightness.
+
+               Reading this file will return the last brightness level set
+               by the hardware, this may be different from the current
+               brightness. Reading this file when no hw brightness change
+               event has happened will return an ENODATA error.
+
 What:          /sys/class/leds/<led>/trigger
 Date:          March 2006
 KernelVersion: 2.6.17