leds: core: Add led_set_brightness_nosleep{nopm} functions
This patch adds led_set_brightness_nosleep() and led_set_brightness_nopm()
functions, that guarantee setting LED brightness in a non-blocking way.
The latter is used from pm_ops context and doesn't modify the brightness
cached in the struct led_classdev. Its execution always ends up with
a call to brightness setting op - either directly or through
a set_brightness_work, regardless of LED_SUSPENDED flag state.
The patch also replaces led_set_brightness_async() with
led_set_brightness_nosleep() in all places where the most vital was setting
brightness in a non sleeping way but not necessarily asynchronously, which
is not needed for non-blocking drivers.
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
index 7cf5924..3d16859 100644
--- a/drivers/leds/led-core.c
+++ b/drivers/leds/led-core.c
@@ -32,7 +32,7 @@
unsigned long delay;
if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
- led_set_brightness_async(led_cdev, LED_OFF);
+ led_set_brightness_nosleep(led_cdev, LED_OFF);
return;
}
@@ -60,7 +60,7 @@
delay = led_cdev->blink_delay_off;
}
- led_set_brightness_async(led_cdev, brightness);
+ led_set_brightness_nosleep(led_cdev, brightness);
/* Return in next iteration if led is in one-shot mode and we are in
* the final blink state so that the led is toggled each delay_on +
@@ -110,13 +110,14 @@
/* never on - just set to off */
if (!delay_on) {
- led_set_brightness_async(led_cdev, LED_OFF);
+ led_set_brightness_nosleep(led_cdev, LED_OFF);
return;
}
/* never off - just set to brightness */
if (!delay_off) {
- led_set_brightness_async(led_cdev, led_cdev->blink_brightness);
+ led_set_brightness_nosleep(led_cdev,
+ led_cdev->blink_brightness);
return;
}
@@ -217,7 +218,7 @@
}
if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) {
- led_set_brightness_async(led_cdev, brightness);
+ led_set_brightness_nosleep(led_cdev, brightness);
return;
} else if (led_cdev->flags & SET_BRIGHTNESS_SYNC)
ret = led_set_brightness_sync(led_cdev, brightness);
@@ -230,6 +231,33 @@
}
EXPORT_SYMBOL_GPL(led_set_brightness);
+void led_set_brightness_nopm(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ /* Use brightness_set op if available, it is guaranteed not to sleep */
+ if (led_cdev->brightness_set) {
+ led_cdev->brightness_set(led_cdev, value);
+ return;
+ }
+
+ /* If brightness setting can sleep, delegate it to a work queue task */
+ led_cdev->delayed_set_value = value;
+ schedule_work(&led_cdev->set_brightness_work);
+}
+EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
+
+void led_set_brightness_nosleep(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ led_cdev->brightness = min(value, led_cdev->max_brightness);
+
+ if (led_cdev->flags & LED_SUSPENDED)
+ return;
+
+ led_set_brightness_nopm(led_cdev, led_cdev->brightness);
+}
+EXPORT_SYMBOL_GPL(led_set_brightness_nosleep);
+
int led_update_brightness(struct led_classdev *led_cdev)
{
int ret = 0;
