Hi!

quoted

quoted

quoted

+++ b/drivers/leds/trigger/ledtrig-backlight.c

@@ -114,6 +114,8 @@ static int bl_trig_activate(struct led_classdev *led)
 	n->old_status = UNBLANK;
 	n->notifier.notifier_call = fb_notifier_callback;
 
+	led_set_brightness(led, LED_ON);
+

This looks fishy.

Maybe you should use a default-state = "keep" instead? (and you'll have
to support it in the LED driver).

That'll give you proper "don't touch the LED if it was turned on" behavior,
which is what you seem to want.

Actually no, that's not what I want. LED should go on if the display
is active, as soon as trigger is activated.

Unfortunately, I have see no good way to tell if the display is
active (and display is usually active when trigger is activated).

default-state DT property can be also set to "on"
(see Documentation/devicetree/bindings/leds/common.txt).

Yes, except that it does not work with all drivers :-(. In particular,
it does not work with lm3532.

We should really move more of the device tree parsing into core, so
that there's one place to fix...
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
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