leds: fix brightness changing when software blinking is active

The following sequence:
echo timer >/sys/class/leds/<name>/trigger
echo 1 >/sys/class/leds/<name>/brightness
should change the ON brightness for blinking.
The function led_set_brightness() was mistakenly initiating the
delayed blink stop procedure, which resulted in no blinking with
the timer trigger still active.

This patch fixes the problem by changing led_set_brightness()
to not initiate the delayed blink stop when brightness is not 0.

CC: Richard Purdie <[e-mail]>
CC: Kyungmin Park <[e-mail]>
CC: [e-mail]
CC: [e-mail]

Acked-by: Jacek Anaszewski <[e-mail]>
Signed-off-by: Stas Sergeev <[e-mail]>
Signed-off-by: Bryan Wu <[e-mail]>

drivers/leds/led-class.c

···
 	brightness = led_get_brightness(led_cdev);
 	if (!brightness) {
 		/* Time to switch the LED on. */
+		if (led_cdev->delayed_set_value) {
+			led_cdev->blink_brightness =
+					led_cdev->delayed_set_value;
+			led_cdev->delayed_set_value = 0;
+		}
 		brightness = led_cdev->blink_brightness;
 		delay = led_cdev->blink_delay_on;
 	} else {

drivers/leds/led-core.c

···
 {
 	int ret = 0;
 
-	/* delay brightness setting if need to stop soft-blink timer */
+	/* delay brightness if soft-blink is active */
 	if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) {
 		led_cdev->delayed_set_value = brightness;
-		schedule_work(&led_cdev->set_brightness_work);
+		if (brightness == LED_OFF)
+			schedule_work(&led_cdev->set_brightness_work);
 		return;
 	}