leds: core: Add two new LED_BLINK_ flags

This patch adds LED_BLINK_BRIGHTNESS_CHANGE flag to indicate that blink
brightness has changed, and LED_BLINK_DISABLE flag to indicate that
blinking deactivation has been requested. In order to use the flags
led_timer_function and set_brightness_delayed callbacks as well as
led_set_brightness() function are being modified. The main goal of these
modifications is to prepare set_brightness_work for extension of the
scope of its responsibilities.

Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>

diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
index ee9309e..7cf5924 100644 (file)
--- a/drivers/leds/led-core.c
+++ b/drivers/leds/led-core.c
@@ -44,18 +44,18 @@ static void led_timer_function(unsigned long data)
        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 {
                /* Store the current brightness value to be able
                 * to restore it when the delay_off period is over.
+                * Do it only if there is no pending blink brightness
+                * change, to avoid overwriting the new value.
                 */
-               led_cdev->blink_brightness = brightness;
+               if (!(led_cdev->flags & LED_BLINK_BRIGHTNESS_CHANGE))
+                       led_cdev->blink_brightness = brightness;
+               else
+                       led_cdev->flags &= ~LED_BLINK_BRIGHTNESS_CHANGE;
                brightness = LED_OFF;
                delay = led_cdev->blink_delay_off;
        }
@@ -84,7 +84,11 @@ static void set_brightness_delayed(struct work_struct *ws)
        struct led_classdev *led_cdev =
                container_of(ws, struct led_classdev, set_brightness_work);
 
-       led_stop_software_blink(led_cdev);
+       if (led_cdev->flags & LED_BLINK_DISABLE) {
+               led_cdev->delayed_set_value = LED_OFF;
+               led_stop_software_blink(led_cdev);
+               led_cdev->flags &= ~LED_BLINK_DISABLE;
+       }
 
        led_set_brightness_async(led_cdev, led_cdev->delayed_set_value);
 }
@@ -192,11 +196,23 @@ void led_set_brightness(struct led_classdev *led_cdev,
 {
        int ret = 0;
 
-       /* delay brightness if soft-blink is active */
+       /*
+        * In case blinking is on delay brightness setting
+        * until the next timer tick.
+        */
        if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) {
-               led_cdev->delayed_set_value = brightness;
-               if (brightness == LED_OFF)
+               /*
+                * If we need to disable soft blinking delegate this to the
+                * work queue task to avoid problems in case we are called
+                * from hard irq context.
+                */
+               if (brightness == LED_OFF) {
+                       led_cdev->flags |= LED_BLINK_DISABLE;
                        schedule_work(&led_cdev->set_brightness_work);
+               } else {
+                       led_cdev->flags |= LED_BLINK_BRIGHTNESS_CHANGE;
+                       led_cdev->blink_brightness = brightness;
+               }
                return;
        }
 

diff --git a/include/linux/leds.h b/include/linux/leds.h
index fa359c7..7b67450 100644 (file)
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -44,10 +44,12 @@ struct led_classdev {
 #define LED_BLINK_ONESHOT      (1 << 17)
 #define LED_BLINK_ONESHOT_STOP (1 << 18)
 #define LED_BLINK_INVERT       (1 << 19)
-#define LED_SYSFS_DISABLE      (1 << 20)
-#define SET_BRIGHTNESS_ASYNC   (1 << 21)
-#define SET_BRIGHTNESS_SYNC    (1 << 22)
-#define LED_DEV_CAP_FLASH      (1 << 23)
+#define LED_BLINK_BRIGHTNESS_CHANGE (1 << 20)
+#define LED_BLINK_DISABLE      (1 << 21)
+#define LED_SYSFS_DISABLE      (1 << 22)
+#define SET_BRIGHTNESS_ASYNC   (1 << 23)
+#define SET_BRIGHTNESS_SYNC    (1 << 24)
+#define LED_DEV_CAP_FLASH      (1 << 25)
 
        /* Set LED brightness level */
        /* Must not sleep, use a workqueue if needed */