Commit 5c51277a authored by Mika Westerberg's avatar Mika Westerberg Committed by Rafael J. Wysocki
Browse files

leds: leds-gpio: Add support for GPIO descriptors 



GPIO descriptors are the preferred way over legacy GPIO numbers
nowadays. Convert the driver to use GPIO descriptors internally but
still allow passing legacy GPIO numbers from platform data to support
existing platforms.

Signed-off-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: default avatarAlexandre Courbot <acourbot@nvidia.com>
Acked-by: default avatarBryan Wu <cooloney@gmail.com>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Acked-by: default avatarGrant Likely <grant.likely@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent c479ff09

drivers/leds/leds-gpio.c

+45 −35
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
 */

#include <linux/err.h>

#include <linux/gpio.h>

#include <linux/gpio/consumer.h>

#include <linux/kernel.h>

#include <linux/leds.h>

#include <linux/module.h>
@@ -24,11 +25,10 @@ 


struct gpio_led_data {

	struct led_classdev cdev;

	unsigned gpio;

	struct gpio_desc *gpiod;

	struct work_struct work;

	u8 new_level;

	u8 can_sleep;

	u8 active_low;

	u8 blinking;

	int (*platform_gpio_blink_set)(unsigned gpio, int state,

			unsigned long *delay_on, unsigned long *delay_off);
@@ -40,12 +40,16 @@ static void gpio_led_work(struct work_struct *work) 
		container_of(work, struct gpio_led_data, work);



	if (led_dat->blinking) {

		led_dat->platform_gpio_blink_set(led_dat->gpio,

						 led_dat->new_level,

						 NULL, NULL);

		int gpio = desc_to_gpio(led_dat->gpiod);

		int level = led_dat->new_level;



		if (gpiod_is_active_low(led_dat->gpiod))

			level = !level;



		led_dat->platform_gpio_blink_set(gpio, level, NULL, NULL);

		led_dat->blinking = 0;

	} else

		gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level);

		gpiod_set_value_cansleep(led_dat->gpiod, led_dat->new_level);

}



static void gpio_led_set(struct led_classdev *led_cdev,
@@ -60,9 +64,6 @@ static void gpio_led_set(struct led_classdev *led_cdev, 
	else

		level = 1;



	if (led_dat->active_low)

		level = !level;



	/* Setting GPIOs with I2C/etc requires a task context, and we don't

	 * seem to have a reliable way to know if we're already in one; so

	 * let's just assume the worst.
@@ -72,11 +73,16 @@ static void gpio_led_set(struct led_classdev *led_cdev, 
		schedule_work(&led_dat->work);

	} else {

		if (led_dat->blinking) {

			led_dat->platform_gpio_blink_set(led_dat->gpio, level,

							 NULL, NULL);

			int gpio = desc_to_gpio(led_dat->gpiod);



			if (gpiod_is_active_low(led_dat->gpiod))

				level = !level;



			led_dat->platform_gpio_blink_set(gpio, level, NULL,

							 NULL);

			led_dat->blinking = 0;

		} else

			gpio_set_value(led_dat->gpio, level);

			gpiod_set_value(led_dat->gpiod, level);

	}

}
@@ -85,9 +91,10 @@ static int gpio_blink_set(struct led_classdev *led_cdev, 
{

	struct gpio_led_data *led_dat =

		container_of(led_cdev, struct gpio_led_data, cdev);

	int gpio = desc_to_gpio(led_dat->gpiod);



	led_dat->blinking = 1;

	return led_dat->platform_gpio_blink_set(led_dat->gpio, GPIO_LED_BLINK,

	return led_dat->platform_gpio_blink_set(gpio, GPIO_LED_BLINK,

						delay_on, delay_off);

}
@@ -97,7 +104,8 @@ static int create_gpio_led(const struct gpio_led *template, 
{

	int ret, state;



	led_dat->gpio = -1;

	if (!template->gpiod) {

		unsigned long flags = 0;



		/* skip leds that aren't available */

		if (!gpio_is_valid(template->gpio)) {
@@ -106,15 +114,23 @@ static int create_gpio_led(const struct gpio_led *template, 
			return 0;

		}



	ret = devm_gpio_request(parent, template->gpio, template->name);

		if (template->active_low)

			flags |= GPIOF_ACTIVE_LOW;



		ret = devm_gpio_request_one(parent, template->gpio, flags,

					    template->name);

		if (ret < 0)

			return ret;



		led_dat->gpiod = gpio_to_desc(template->gpio);

		if (IS_ERR(led_dat->gpiod))

			return PTR_ERR(led_dat->gpiod);

	}



	led_dat->cdev.name = template->name;

	led_dat->cdev.default_trigger = template->default_trigger;

	led_dat->gpio = template->gpio;

	led_dat->can_sleep = gpio_cansleep(template->gpio);

	led_dat->active_low = template->active_low;

	led_dat->gpiod = template->gpiod;

	led_dat->can_sleep = gpiod_cansleep(template->gpiod);

	led_dat->blinking = 0;

	if (blink_set) {

		led_dat->platform_gpio_blink_set = blink_set;
@@ -122,30 +138,24 @@ static int create_gpio_led(const struct gpio_led *template, 
	}

	led_dat->cdev.brightness_set = gpio_led_set;

	if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)

		state = !!gpio_get_value_cansleep(led_dat->gpio) ^ led_dat->active_low;

		state = !!gpiod_get_value_cansleep(led_dat->gpiod);

	else

		state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);

	led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;

	if (!template->retain_state_suspended)

		led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;



	ret = gpio_direction_output(led_dat->gpio, led_dat->active_low ^ state);

	ret = gpiod_direction_output(led_dat->gpiod, state);

	if (ret < 0)

		return ret;



	INIT_WORK(&led_dat->work, gpio_led_work);



	ret = led_classdev_register(parent, &led_dat->cdev);

	if (ret < 0)

		return ret;



	return 0;

	return led_classdev_register(parent, &led_dat->cdev);

}



static void delete_gpio_led(struct gpio_led_data *led)

{

	if (!gpio_is_valid(led->gpio))

		return;

	led_classdev_unregister(&led->cdev);

	cancel_work_sync(&led->work);

}

include/linux/leds.h

+1 −0
Original line number Diff line number Diff line
@@ -261,6 +261,7 @@ struct gpio_led { 
	unsigned	retain_state_suspended : 1;

	unsigned	default_state : 2;

	/* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */

	struct gpio_desc *gpiod;

};

#define LEDS_GPIO_DEFSTATE_OFF		0

#define LEDS_GPIO_DEFSTATE_ON		1

CRA Git | Maintained and supported by SUSTech CRA and CCSE