leds: Add support for setting brightness in a synchronous way

There are use cases when setting a LED brightness has to
have immediate effect (e.g. setting a torch LED brightness).
This patch extends LED subsystem to support such operations.
The LED subsystem internal API __led_set_brightness is changed
to led_set_brightness_async and new led_set_brightness_sync API
is added.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

6 files changed, 17 insertions, 15 deletions

diff --git a/drivers/leds/trigger/ledtrig-backlight.c b/drivers/leds/trigger/ledtrig-backlight.c
index 47e55aa9eefa..59eca17d9661 100644
--- a/drivers/leds/trigger/ledtrig-backlight.c
+++ b/drivers/leds/trigger/ledtrig-backlight.c
@@ -51,9 +51,9 @@ static int fb_notifier_callback(struct notifier_block *p,
 
         if ((n->old_status == UNBLANK) ^ n->invert) {
                 n->brightness = led->brightness;
-                __led_set_brightness(led, LED_OFF);
+                led_set_brightness_async(led, LED_OFF);
         } else {
-                __led_set_brightness(led, n->brightness);
+                led_set_brightness_async(led, n->brightness);
         }
 
         n->old_status = new_status;
@@ -89,9 +89,9 @@ static ssize_t bl_trig_invert_store(struct device *dev,
 
         /* After inverting, we need to update the LED. */
         if ((n->old_status == BLANK) ^ n->invert)
-                __led_set_brightness(led, LED_OFF);
+                led_set_brightness_async(led, LED_OFF);
         else
-                __led_set_brightness(led, n->brightness);
+                led_set_brightness_async(led, n->brightness);
 
         return num;
 }
diff --git a/drivers/leds/trigger/ledtrig-default-on.c b/drivers/leds/trigger/ledtrig-default-on.c
index 81a91be8e18d..6f38f883aaf1 100644
--- a/drivers/leds/trigger/ledtrig-default-on.c
+++ b/drivers/leds/trigger/ledtrig-default-on.c
@@ -19,7 +19,7 @@
 
 static void defon_trig_activate(struct led_classdev *led_cdev)
 {
-        __led_set_brightness(led_cdev, led_cdev->max_brightness);
+        led_set_brightness_async(led_cdev, led_cdev->max_brightness);
 }
 
 static struct led_trigger defon_led_trigger = {
diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
index c86c41826476..4cc7040746c6 100644
--- a/drivers/leds/trigger/ledtrig-gpio.c
+++ b/drivers/leds/trigger/ledtrig-gpio.c
@@ -54,12 +54,12 @@ static void gpio_trig_work(struct work_struct *work)
 
         if (tmp) {
                 if (gpio_data->desired_brightness)
-                        __led_set_brightness(gpio_data->led,
+                        led_set_brightness_async(gpio_data->led,
                                            gpio_data->desired_brightness);
                 else
-                        __led_set_brightness(gpio_data->led, LED_FULL);
+                        led_set_brightness_async(gpio_data->led, LED_FULL);
         } else {
-                __led_set_brightness(gpio_data->led, LED_OFF);
+                led_set_brightness_async(gpio_data->led, LED_OFF);
         }
 }
 
diff --git a/drivers/leds/trigger/ledtrig-heartbeat.c b/drivers/leds/trigger/ledtrig-heartbeat.c
index 5c8464a33172..fea6871d2609 100644
--- a/drivers/leds/trigger/ledtrig-heartbeat.c
+++ b/drivers/leds/trigger/ledtrig-heartbeat.c
@@ -74,7 +74,7 @@ static void led_heartbeat_function(unsigned long data)
                 break;
         }
 
-        __led_set_brightness(led_cdev, brightness);
+        led_set_brightness_async(led_cdev, brightness);
         mod_timer(&heartbeat_data->timer, jiffies + delay);
 }
 
diff --git a/drivers/leds/trigger/ledtrig-oneshot.c b/drivers/leds/trigger/ledtrig-oneshot.c
index cb4c7466692a..fbd02cdc3ad7 100644
--- a/drivers/leds/trigger/ledtrig-oneshot.c
+++ b/drivers/leds/trigger/ledtrig-oneshot.c
@@ -63,9 +63,9 @@ static ssize_t led_invert_store(struct device *dev,
         oneshot_data->invert = !!state;
 
         if (oneshot_data->invert)
-                __led_set_brightness(led_cdev, LED_FULL);
+                led_set_brightness_async(led_cdev, LED_FULL);
         else
-                __led_set_brightness(led_cdev, LED_OFF);
+                led_set_brightness_async(led_cdev, LED_OFF);
 
         return size;
 }
diff --git a/drivers/leds/trigger/ledtrig-transient.c b/drivers/leds/trigger/ledtrig-transient.c
index e5abc00bb00c..3c34de404d18 100644
--- a/drivers/leds/trigger/ledtrig-transient.c
+++ b/drivers/leds/trigger/ledtrig-transient.c
@@ -41,7 +41,7 @@ static void transient_timer_function(unsigned long data)
         struct transient_trig_data *transient_data = led_cdev->trigger_data;
 
         transient_data->activate = 0;
-        __led_set_brightness(led_cdev, transient_data->restore_state);
+        led_set_brightness_async(led_cdev, transient_data->restore_state);
 }
 
 static ssize_t transient_activate_show(struct device *dev,
@@ -72,7 +72,8 @@ static ssize_t transient_activate_store(struct device *dev,
         if (state == 0 && transient_data->activate == 1) {
                 del_timer(&transient_data->timer);
                 transient_data->activate = state;
-                __led_set_brightness(led_cdev, transient_data->restore_state);
+                led_set_brightness_async(led_cdev,
+                                        transient_data->restore_state);
                 return size;
         }
 
@@ -80,7 +81,7 @@ static ssize_t transient_activate_store(struct device *dev,
         if (state == 1 && transient_data->activate == 0 &&
             transient_data->duration != 0) {
                 transient_data->activate = state;
-                __led_set_brightness(led_cdev, transient_data->state);
+                led_set_brightness_async(led_cdev, transient_data->state);
                 transient_data->restore_state =
                     (transient_data->state == LED_FULL) ? LED_OFF : LED_FULL;
                 mod_timer(&transient_data->timer,
@@ -203,7 +204,8 @@ static void transient_trig_deactivate(struct led_classdev *led_cdev)
 
         if (led_cdev->activated) {
                 del_timer_sync(&transient_data->timer);
-                __led_set_brightness(led_cdev, transient_data->restore_state);
+                led_set_brightness_async(led_cdev,
+                                        transient_data->restore_state);
                 device_remove_file(led_cdev->dev, &dev_attr_activate);
                 device_remove_file(led_cdev->dev, &dev_attr_duration);
                 device_remove_file(led_cdev->dev, &dev_attr_state);