Hi Pavel,

Thanks for the patch.

On 10/03/2016 10:10 AM, Pavel Machek wrote:

sysfs-class-led fails to mention some important details. Also fix led
vs LED and english.

Signed-off-by: Pavel Machek <[email protected]>

--- a/Documentation/ABI/testing/sysfs-class-led
+++ b/Documentation/ABI/testing/sysfs-class-led
@@ -4,16 +4,25 @@ KernelVersion:        2.6.17
 Contact:       Richard Purdie <[email protected]>
 Description:
                Set the brightness of the LED. Most LEDs don't
-               have hardware brightness support so will just be turned on for
+               have hardware brightness support, so will just be turned on for
                non-zero brightness settings. The value is between 0 and
                /sys/class/leds/<led>/max_brightness.

+               Writing 0 to this file clears active trigger.
+
+               Writing non-zero to this file while trigger is active changes 
the
+               top brightness trigger is going to use.

This is true only in case of timer trigger, as it uses blink_brightness
property from struct led_classdev to cache current brightness, when the
the LED is in the off cycle. This is part of software blink fallback
functionality.

In case of heartbeat trigger max_brightness is always used for top level
brightness. We'd need to refactor the trigger a bit to allow for
different top brightness levels.

+               
+
 What:          /sys/class/leds/<led>/max_brightness
 Date:          March 2006
 KernelVersion: 2.6.17
 Contact:       Richard Purdie <[email protected]>
 Description:
-               Maximum brightness level for this led, default is 255 
(LED_FULL).
+               Maximum brightness level for this LED, default is 255 
(LED_FULL).
+
+               If the LED does not support different brightness levels, this
+               should be 1.

 What:          /sys/class/leds/<led>/trigger
 Date:          March 2006
@@ -21,7 +30,7 @@ KernelVersion:        2.6.17
 Contact:       Richard Purdie <[email protected]>
 Description:
                Set the trigger for this LED. A trigger is a kernel based source
-               of led events.
+               of LED events.
                You can change triggers in a similar manner to the way an IO
                scheduler is chosen. Trigger specific parameters can appear in
                /sys/class/leds/<led> once a given trigger is selected.



--
Best regards,
Jacek Anaszewski

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