Commit 4d71a4a1 authored by Jacek Anaszewski's avatar Jacek Anaszewski Committed by Bryan Wu
Browse files

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: default avatarJacek Anaszewski <j.anaszewski@samsung.com>
Acked-by: default avatarKyungmin Park <kyungmin.park@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: default avatarBryan Wu <cooloney@gmail.com>
parent acd899e4

drivers/leds/led-class.c

+6 −4
Original line number Diff line number Diff line
@@ -55,7 +55,7 @@ static ssize_t brightness_store(struct device *dev, 


	if (state == LED_OFF)

		led_trigger_remove(led_cdev);

	__led_set_brightness(led_cdev, state);

	led_set_brightness(led_cdev, state);



	ret = size;

unlock:
@@ -109,7 +109,7 @@ static void led_timer_function(unsigned long data) 
	unsigned long delay;



	if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {

		__led_set_brightness(led_cdev, LED_OFF);

		led_set_brightness_async(led_cdev, LED_OFF);

		return;

	}
@@ -132,7 +132,7 @@ static void led_timer_function(unsigned long data) 
		delay = led_cdev->blink_delay_off;

	}



	__led_set_brightness(led_cdev, brightness);

	led_set_brightness_async(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 +
@@ -158,7 +158,7 @@ static void set_brightness_delayed(struct work_struct *ws) 


	led_stop_software_blink(led_cdev);



	__led_set_brightness(led_cdev, led_cdev->delayed_set_value);

	led_set_brightness_async(led_cdev, led_cdev->delayed_set_value);

}



/**
@@ -233,6 +233,8 @@ int led_classdev_register(struct device *parent, struct led_classdev *led_cdev) 
	if (!led_cdev->max_brightness)

		led_cdev->max_brightness = LED_FULL;



	led_cdev->flags |= SET_BRIGHTNESS_ASYNC;



	led_update_brightness(led_cdev);



	INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);

drivers/leds/led-core.c

+15 −3
Original line number Diff line number Diff line
@@ -42,13 +42,13 @@ static void led_set_software_blink(struct led_classdev *led_cdev, 


	/* never on - just set to off */

	if (!delay_on) {

		__led_set_brightness(led_cdev, LED_OFF);

		led_set_brightness_async(led_cdev, LED_OFF);

		return;

	}



	/* never off - just set to brightness */

	if (!delay_off) {

		__led_set_brightness(led_cdev, led_cdev->blink_brightness);

		led_set_brightness_async(led_cdev, led_cdev->blink_brightness);

		return;

	}
@@ -117,6 +117,8 @@ EXPORT_SYMBOL_GPL(led_stop_software_blink); 
void led_set_brightness(struct led_classdev *led_cdev,

			enum led_brightness brightness)

{

	int ret = 0;



	/* delay brightness setting if need to stop soft-blink timer */

	if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) {

		led_cdev->delayed_set_value = brightness;
@@ -124,7 +126,17 @@ void led_set_brightness(struct led_classdev *led_cdev, 
		return;

	}



	__led_set_brightness(led_cdev, brightness);

	if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) {

		led_set_brightness_async(led_cdev, brightness);

		return;

	} else if (led_cdev->flags & SET_BRIGHTNESS_SYNC)

		ret = led_set_brightness_sync(led_cdev, brightness);

	else

		ret = -EINVAL;



	if (ret < 0)

		dev_dbg(led_cdev->dev, "Setting LED brightness failed (%d)\n",

			ret);

}

EXPORT_SYMBOL(led_set_brightness);

drivers/leds/leds.h

+16 −4
Original line number Diff line number Diff line
@@ -17,16 +17,28 @@ 
#include <linux/rwsem.h>

#include <linux/leds.h>



static inline void __led_set_brightness(struct led_classdev *led_cdev,

static inline void led_set_brightness_async(struct led_classdev *led_cdev,

					enum led_brightness value)

{

	if (value > led_cdev->max_brightness)

		value = led_cdev->max_brightness;

	led_cdev->brightness = value;

	led_cdev->brightness = min(value, led_cdev->max_brightness);



	if (!(led_cdev->flags & LED_SUSPENDED))

		led_cdev->brightness_set(led_cdev, value);

}



static inline int led_set_brightness_sync(struct led_classdev *led_cdev,

					enum led_brightness value)

{

	int ret = 0;



	led_cdev->brightness = min(value, led_cdev->max_brightness);



	if (!(led_cdev->flags & LED_SUSPENDED))

		ret = led_cdev->brightness_set_sync(led_cdev,

						led_cdev->brightness);

	return ret;

}



static inline int led_get_brightness(struct led_classdev *led_cdev)

{

	return led_cdev->brightness;

drivers/leds/trigger/ledtrig-backlight.c

+4 −4
Original line number Diff line number Diff line
@@ -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;

}

drivers/leds/trigger/ledtrig-default-on.c

+1 −1
Original line number Diff line number Diff line
@@ -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 = {

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