leds: disable triggers on brightness set

Disable any active triggers when the brightness attribute is
set to zero.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Márton Németh <nm127@freemail.hu>
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>

1 files changed, 19 insertions, 4 deletions

diff --git a/drivers/leds/ledtrig-timer.c b/drivers/leds/ledtrig-timer.c
index 82c55d6e4902..706297765d93 100644
--- a/drivers/leds/ledtrig-timer.c
+++ b/drivers/leds/ledtrig-timer.c
@@ -25,6 +25,9 @@
 #include "leds.h"
 
 struct timer_trig_data {
+        int brightness_on;              /* LED brightness during "on" period.
+                                         * (LED_OFF < brightness_on <= LED_FULL)
+                                         */
         unsigned long delay_on;         /* milliseconds on */
         unsigned long delay_off;        /* milliseconds off */
         struct timer_list timer;
@@ -34,17 +37,26 @@ static void led_timer_function(unsigned long data)
 {
         struct led_classdev *led_cdev = (struct led_classdev *) data;
         struct timer_trig_data *timer_data = led_cdev->trigger_data;
-        unsigned long brightness = LED_OFF;
-        unsigned long delay = timer_data->delay_off;
+        unsigned long brightness;
+        unsigned long delay;
 
         if (!timer_data->delay_on || !timer_data->delay_off) {
                 led_set_brightness(led_cdev, LED_OFF);
                 return;
         }
 
-        if (!led_cdev->brightness) {
-                brightness = LED_FULL;
+        brightness = led_get_brightness(led_cdev);
+        if (!brightness) {
+                /* Time to switch the LED on. */
+                brightness = timer_data->brightness_on;
                 delay = timer_data->delay_on;
+        } else {
+                /* Store the current brightness value to be able
+                 * to restore it when the delay_off period is over.
+                 */
+                timer_data->brightness_on = brightness;
+                brightness = LED_OFF;
+                delay = timer_data->delay_off;
         }
 
         led_set_brightness(led_cdev, brightness);
@@ -156,6 +168,9 @@ static void timer_trig_activate(struct led_classdev *led_cdev)
         if (!timer_data)
                 return;
 
+        timer_data->brightness_on = led_get_brightness(led_cdev);
+        if (timer_data->brightness_on == LED_OFF)
+                timer_data->brightness_on = LED_FULL;
         led_cdev->trigger_data = timer_data;
 
         init_timer(&timer_data->timer);