leds: support automatic start of blinking with ledtrig-timer

By setting initial values blink_delay_on and blink_delay_off in a
led_classdev struct, this change starts the blinking when the led is
initialized.

With this patch, you can initialize blink_delay_on and blink_delay_off in
led_classdev with default_trigger set to "timer", and the led will start
up blinking.  The current ledtrig-timer implementation ignores any initial
blink_delay_on/blink_delay_off settings, and requires setting
blink_delay_on/blink_delay_off (typically from userspace) before the led
blinks.

Signed-off-by: Esben Haabendal <eha@doredevelopment.dk>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index d5a4ade88991..dc3d3d83191a 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -131,7 +131,8 @@ static void led_set_software_blink(struct led_classdev *led_cdev,
         if (!led_cdev->blink_brightness)
                 led_cdev->blink_brightness = led_cdev->max_brightness;
 
-        if (delay_on == led_cdev->blink_delay_on &&
+        if (led_get_trigger_data(led_cdev) &&
+            delay_on == led_cdev->blink_delay_on &&
             delay_off == led_cdev->blink_delay_off)
                 return;