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authorLinus Torvalds <torvalds@linux-foundation.org>2017-02-20 17:31:23 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-02-20 17:31:23 -0800
commit7aa7d608112baf63a0b1278955f9619427373807 (patch)
treeb6a7ed4233ddf3a6760bd72aed93d4b83b1f7c45 /Documentation/ABI/testing
parent85adbcd54f0982040c8cc7a086f01554b8f64427 (diff)
parentfb3d769173d26268d7bf068094a599bb28b2ac63 (diff)
Merge tag 'leds_for_4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds
Pull LED updates from Jacek Anaszewski: "New features and improvements: - add new optional brightness_hw_changed attribute for the LEDs that may have their brightness level changed autonomously (outside of kernel control) by hardware / firmware. The attribute supports userspace notifications through POLLPRI events - add led_brightness_hw_mon tool that demonstrates how to use the aforementioned feature - add LED_ON enum for LEDs that can be only turned on/off, and don't allow setting other brightness levels - allow for adjusting heartbeat trigger blink brightness level Fixes and cleanups: - avoid harmless maybe-uninitialized warning in leds-ktd2692.c - add context to the existing example entries in common LED bindings to make the documentation more clear" * tag 'leds_for_4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds: leds: ledtrig-heartbeat: Make top brightness adjustable tools/leds: Add led_hw_brightness_mon program leds: class: Add new optional brightness_hw_changed attribute leds: ktd2692: avoid harmless maybe-uninitialized warning leds: add LED_ON brightness as boolean value DT: leds: Improve examples by adding some context
Diffstat (limited to 'Documentation/ABI/testing')
-rw-r--r--Documentation/ABI/testing/sysfs-class-led17
1 files changed, 17 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-led b/Documentation/ABI/testing/sysfs-class-led
index 491cdeedc195..5f67f7ab277b 100644
--- 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