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 <pavel@xxxxxx> --- 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 <rpurdie@xxxxxxxxx> 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 <rpurdie@xxxxxxxxx> 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 <rpurdie@xxxxxxxxx> 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 -- To unsubscribe from this list: send the line "unsubscribe linux-leds" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
