[linux.git] / drivers / leds / leds-gpio.c

/*
 * LEDs driver for GPIOs
 *
 * Copyright (C) 2007 8D Technologies inc.
 * Raphael Assenat <[email protected]>
 * Copyright (C) 2008 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/leds.h>
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/err.h>

struct gpio_led_data {
	struct led_classdev cdev;
	unsigned gpio;
	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);
};

static void gpio_led_work(struct work_struct *work)
{
	struct gpio_led_data	*led_dat =
		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);
		led_dat->blinking = 0;
	} else
		gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level);
}

static void gpio_led_set(struct led_classdev *led_cdev,
	enum led_brightness value)
{
	struct gpio_led_data *led_dat =
		container_of(led_cdev, struct gpio_led_data, cdev);
	int level;

	if (value == LED_OFF)
		level = 0;
	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.
	 */
	if (led_dat->can_sleep) {
		led_dat->new_level = level;
		schedule_work(&led_dat->work);
	} else {
		if (led_dat->blinking) {
			led_dat->platform_gpio_blink_set(led_dat->gpio, level,
							 NULL, NULL);
			led_dat->blinking = 0;
		} else
			gpio_set_value(led_dat->gpio, level);
	}
}

static int gpio_blink_set(struct led_classdev *led_cdev,
	unsigned long *delay_on, unsigned long *delay_off)
{
	struct gpio_led_data *led_dat =
		container_of(led_cdev, struct gpio_led_data, cdev);

	led_dat->blinking = 1;
	return led_dat->platform_gpio_blink_set(led_dat->gpio, GPIO_LED_BLINK,
						delay_on, delay_off);
}

static int create_gpio_led(const struct gpio_led *template,
	struct gpio_led_data *led_dat, struct device *parent,
	int (*blink_set)(unsigned, int, unsigned long *, unsigned long *))
{
	int ret, state;

	led_dat->gpio = -1;

	/* skip leds that aren't available */
	if (!gpio_is_valid(template->gpio)) {
		dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n",
				template->gpio, template->name);
		return 0;
	}

	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->blinking = 0;
	if (blink_set) {
		led_dat->platform_gpio_blink_set = blink_set;
		led_dat->cdev.blink_set = gpio_blink_set;
	}
	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;
	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 = devm_gpio_request_one(parent, template->gpio,
				    (led_dat->active_low ^ state) ?
				    GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
				    template->name);
	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;
}

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);
}

struct gpio_leds_priv {
	int num_leds;
	struct gpio_led_data leds[];
};

static inline int sizeof_gpio_leds_priv(int num_leds)
{
	return sizeof(struct gpio_leds_priv) +
		(sizeof(struct gpio_led_data) * num_leds);
}

/* Code to create from OpenFirmware platform devices */
#ifdef CONFIG_OF_GPIO
static struct gpio_leds_priv *gpio_leds_create_of(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node, *child;
	struct gpio_leds_priv *priv;
	int count, ret;

	/* count LEDs in this device, so we know how much to allocate */
	count = of_get_child_count(np);
	if (!count)
		return ERR_PTR(-ENODEV);

	for_each_child_of_node(np, child)
		if (of_get_gpio(child, 0) == -EPROBE_DEFER)
			return ERR_PTR(-EPROBE_DEFER);

	priv = devm_kzalloc(&pdev->dev, sizeof_gpio_leds_priv(count),
			GFP_KERNEL);
	if (!priv)
		return ERR_PTR(-ENOMEM);

	for_each_child_of_node(np, child) {
		struct gpio_led led = {};
		enum of_gpio_flags flags;
		const char *state;

		led.gpio = of_get_gpio_flags(child, 0, &flags);
		led.active_low = flags & OF_GPIO_ACTIVE_LOW;
		led.name = of_get_property(child, "label", NULL) ? : child->name;
		led.default_trigger =
			of_get_property(child, "linux,default-trigger", NULL);
		state = of_get_property(child, "default-state", NULL);
		if (state) {
			if (!strcmp(state, "keep"))
				led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
			else if (!strcmp(state, "on"))
				led.default_state = LEDS_GPIO_DEFSTATE_ON;
			else
				led.default_state = LEDS_GPIO_DEFSTATE_OFF;
		}

		ret = create_gpio_led(&led, &priv->leds[priv->num_leds++],
				      &pdev->dev, NULL);
		if (ret < 0) {
			of_node_put(child);
			goto err;
		}
	}

	return priv;

err:
	for (count = priv->num_leds - 2; count >= 0; count--)
		delete_gpio_led(&priv->leds[count]);
	return ERR_PTR(-ENODEV);
}

static const struct of_device_id of_gpio_leds_match[] = {
	{ .compatible = "gpio-leds", },
	{},
};
#else /* CONFIG_OF_GPIO */
static struct gpio_leds_priv *gpio_leds_create_of(struct platform_device *pdev)
{
	return ERR_PTR(-ENODEV);
}
#endif /* CONFIG_OF_GPIO */


static int gpio_led_probe(struct platform_device *pdev)
{
	struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
	struct gpio_leds_priv *priv;
	struct pinctrl *pinctrl;
	int i, ret = 0;

	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
	if (IS_ERR(pinctrl))
		dev_warn(&pdev->dev,
			"pins are not configured from the driver\n");

	if (pdata && pdata->num_leds) {
		priv = devm_kzalloc(&pdev->dev,
				sizeof_gpio_leds_priv(pdata->num_leds),
					GFP_KERNEL);
		if (!priv)
			return -ENOMEM;

		priv->num_leds = pdata->num_leds;
		for (i = 0; i < priv->num_leds; i++) {
			ret = create_gpio_led(&pdata->leds[i],
					      &priv->leds[i],
					      &pdev->dev, pdata->gpio_blink_set);
			if (ret < 0) {
				/* On failure: unwind the led creations */
				for (i = i - 1; i >= 0; i--)
					delete_gpio_led(&priv->leds[i]);
				return ret;
			}
		}
	} else {
		priv = gpio_leds_create_of(pdev);
		if (IS_ERR(priv))
			return PTR_ERR(priv);
	}

	platform_set_drvdata(pdev, priv);

	return 0;
}

static int gpio_led_remove(struct platform_device *pdev)
{
	struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < priv->num_leds; i++)
		delete_gpio_led(&priv->leds[i]);

	platform_set_drvdata(pdev, NULL);

	return 0;
}

static struct platform_driver gpio_led_driver = {
	.probe		= gpio_led_probe,
	.remove		= gpio_led_remove,
	.driver		= {
		.name	= "leds-gpio",
		.owner	= THIS_MODULE,
		.of_match_table = of_match_ptr(of_gpio_leds_match),
	},
};

module_platform_driver(gpio_led_driver);

MODULE_AUTHOR("Raphael Assenat <[email protected]>, Trent Piepho <[email protected]>");
MODULE_DESCRIPTION("GPIO LED driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:leds-gpio");
Commit	Line	Data
22e03f3b RA	1	/*
	2	* LEDs driver for GPIOs
	3	*
	4	* Copyright (C) 2007 8D Technologies inc.
	5	* Raphael Assenat <[email protected]>
a7d878af	6	* Copyright (C) 2008 Freescale Semiconductor, Inc.
22e03f3b RA	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*
	12	*/
	13	#include <linux/kernel.h>
	14	#include <linux/init.h>
	15	#include <linux/platform_device.h>
16db7f90	16	#include <linux/gpio.h>
22e03f3b	17	#include <linux/leds.h>
a314c5c0 GL	18	#include <linux/of_platform.h>
a314c5c0 GL	19	#include <linux/of_gpio.h>
5a0e3ad6	20	#include <linux/slab.h>
00852279	21	#include <linux/workqueue.h>
54f4dedb	22	#include <linux/module.h>
8fe4554f	23	#include <linux/pinctrl/consumer.h>
04553e92	24	#include <linux/err.h>
00852279	25
22e03f3b RA	26	struct gpio_led_data {
	27	struct led_classdev cdev;
	28	unsigned gpio;
00852279 DB	29	struct work_struct work;
	30	u8 new_level;
	31	u8 can_sleep;
22e03f3b	32	u8 active_low;
2146325d BH	33	u8 blinking;
2146325d BH	34	int (*platform_gpio_blink_set)(unsigned gpio, int state,
ca3259b3	35	unsigned long delay_on, unsigned long delay_off);
22e03f3b RA	36	};
22e03f3b RA	37
00852279 DB	38	static void gpio_led_work(struct work_struct *work)
	39	{
	40	struct gpio_led_data *led_dat =
	41	container_of(work, struct gpio_led_data, work);
	42
2146325d BH	43	if (led_dat->blinking) {
	44	led_dat->platform_gpio_blink_set(led_dat->gpio,
	45	led_dat->new_level,
	46	NULL, NULL);
	47	led_dat->blinking = 0;
	48	} else
	49	gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level);
00852279	50	}
22e03f3b RA	51
	52	static void gpio_led_set(struct led_classdev *led_cdev,
	53	enum led_brightness value)
	54	{
	55	struct gpio_led_data *led_dat =
	56	container_of(led_cdev, struct gpio_led_data, cdev);
	57	int level;
	58
	59	if (value == LED_OFF)
	60	level = 0;
	61	else
	62	level = 1;
	63
	64	if (led_dat->active_low)
	65	level = !level;
	66
306dd85c DB	67	/* Setting GPIOs with I2C/etc requires a task context, and we don't
	68	* seem to have a reliable way to know if we're already in one; so
	69	* let's just assume the worst.
	70	*/
00852279	71	if (led_dat->can_sleep) {
306dd85c DB	72	led_dat->new_level = level;
306dd85c DB	73	schedule_work(&led_dat->work);
2146325d BH	74	} else {
	75	if (led_dat->blinking) {
	76	led_dat->platform_gpio_blink_set(led_dat->gpio, level,
	77	NULL, NULL);
	78	led_dat->blinking = 0;
	79	} else
	80	gpio_set_value(led_dat->gpio, level);
	81	}
22e03f3b RA	82	}
22e03f3b RA	83
ca3259b3 HVR	84	static int gpio_blink_set(struct led_classdev *led_cdev,
	85	unsigned long delay_on, unsigned long delay_off)
	86	{
	87	struct gpio_led_data *led_dat =
	88	container_of(led_cdev, struct gpio_led_data, cdev);
	89
2146325d BH	90	led_dat->blinking = 1;
	91	return led_dat->platform_gpio_blink_set(led_dat->gpio, GPIO_LED_BLINK,
	92	delay_on, delay_off);
ca3259b3 HVR	93	}
ca3259b3 HVR	94
98ea1ea2	95	static int create_gpio_led(const struct gpio_led *template,
a7d878af	96	struct gpio_led_data led_dat, struct device parent,
2146325d	97	int (blink_set)(unsigned, int, unsigned long , unsigned long *))
a7d878af	98	{
ed88bae6	99	int ret, state;
a7d878af	100
0b4634fc DB	101	led_dat->gpio = -1;
0b4634fc DB	102
d379ee8a DB	103	/* skip leds that aren't available */
d379ee8a DB	104	if (!gpio_is_valid(template->gpio)) {
39de81a9	105	dev_info(parent, "Skipping unavailable LED gpio %d (%s)\n",
d379ee8a	106	template->gpio, template->name);
ac15e950	107	return 0;
d379ee8a DB	108	}
d379ee8a DB	109
a7d878af TP	110	led_dat->cdev.name = template->name;
	111	led_dat->cdev.default_trigger = template->default_trigger;
	112	led_dat->gpio = template->gpio;
	113	led_dat->can_sleep = gpio_cansleep(template->gpio);
	114	led_dat->active_low = template->active_low;
2146325d	115	led_dat->blinking = 0;
a7d878af TP	116	if (blink_set) {
	117	led_dat->platform_gpio_blink_set = blink_set;
	118	led_dat->cdev.blink_set = gpio_blink_set;
	119	}
	120	led_dat->cdev.brightness_set = gpio_led_set;
ed88bae6	121	if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)
dabc69c2	122	state = !!gpio_get_value_cansleep(led_dat->gpio) ^ led_dat->active_low;
ed88bae6 TP	123	else
	124	state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
	125	led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
defb512d RP	126	if (!template->retain_state_suspended)
defb512d RP	127	led_dat->cdev.flags \|= LED_CORE_SUSPENDRESUME;
a7d878af	128
e3b1d44c	129	ret = devm_gpio_request_one(parent, template->gpio,
2d7c22f6 JMC	130	(led_dat->active_low ^ state) ?
	131	GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW,
	132	template->name);
a7d878af	133	if (ret < 0)
a99d76f9 JH	134	return ret;
a99d76f9 JH	135
a7d878af TP	136	INIT_WORK(&led_dat->work, gpio_led_work);
	137
	138	ret = led_classdev_register(parent, &led_dat->cdev);
	139	if (ret < 0)
e3b1d44c	140	return ret;
a7d878af TP	141
a7d878af TP	142	return 0;
a7d878af TP	143	}
	144
	145	static void delete_gpio_led(struct gpio_led_data *led)
	146	{
d379ee8a DB	147	if (!gpio_is_valid(led->gpio))
d379ee8a DB	148	return;
a7d878af TP	149	led_classdev_unregister(&led->cdev);
a7d878af TP	150	cancel_work_sync(&led->work);
a7d878af TP	151	}
a7d878af TP	152
a314c5c0 GL	153	struct gpio_leds_priv {
	154	int num_leds;
	155	struct gpio_led_data leds[];
	156	};
22e03f3b	157
a314c5c0	158	static inline int sizeof_gpio_leds_priv(int num_leds)
22e03f3b	159	{
a314c5c0 GL	160	return sizeof(struct gpio_leds_priv) +
a314c5c0 GL	161	(sizeof(struct gpio_led_data) * num_leds);
22e03f3b RA	162	}
22e03f3b RA	163
a7d878af	164	/* Code to create from OpenFirmware platform devices */
2bcc7ed5	165	#ifdef CONFIG_OF_GPIO
98ea1ea2	166	static struct gpio_leds_priv gpio_leds_create_of(struct platform_device pdev)
a7d878af	167	{
a314c5c0 GL	168	struct device_node np = pdev->dev.of_node, child;
a314c5c0 GL	169	struct gpio_leds_priv *priv;
127aedc8	170	int count, ret;
a7d878af	171
a314c5c0	172	/* count LEDs in this device, so we know how much to allocate */
127aedc8	173	count = of_get_child_count(np);
a7d878af	174	if (!count)
04553e92 RS	175	return ERR_PTR(-ENODEV);
	176
	177	for_each_child_of_node(np, child)
	178	if (of_get_gpio(child, 0) == -EPROBE_DEFER)
	179	return ERR_PTR(-EPROBE_DEFER);
a7d878af	180
198b8611 SK	181	priv = devm_kzalloc(&pdev->dev, sizeof_gpio_leds_priv(count),
198b8611 SK	182	GFP_KERNEL);
a314c5c0	183	if (!priv)
04553e92	184	return ERR_PTR(-ENOMEM);
a7d878af	185
a7d878af	186	for_each_child_of_node(np, child) {
0493a4ff	187	struct gpio_led led = {};
a7d878af	188	enum of_gpio_flags flags;
ed88bae6	189	const char *state;
a7d878af TP	190
	191	led.gpio = of_get_gpio_flags(child, 0, &flags);
	192	led.active_low = flags & OF_GPIO_ACTIVE_LOW;
	193	led.name = of_get_property(child, "label", NULL) ? : child->name;
	194	led.default_trigger =
	195	of_get_property(child, "linux,default-trigger", NULL);
ed88bae6 TP	196	state = of_get_property(child, "default-state", NULL);
	197	if (state) {
	198	if (!strcmp(state, "keep"))
	199	led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
a314c5c0	200	else if (!strcmp(state, "on"))
ed88bae6 TP	201	led.default_state = LEDS_GPIO_DEFSTATE_ON;
	202	else
	203	led.default_state = LEDS_GPIO_DEFSTATE_OFF;
	204	}
a7d878af	205
a314c5c0 GL	206	ret = create_gpio_led(&led, &priv->leds[priv->num_leds++],
a314c5c0 GL	207	&pdev->dev, NULL);
a7d878af TP	208	if (ret < 0) {
	209	of_node_put(child);
	210	goto err;
	211	}
	212	}
	213
a314c5c0	214	return priv;
a7d878af TP	215
a7d878af TP	216	err:
a314c5c0 GL	217	for (count = priv->num_leds - 2; count >= 0; count--)
a314c5c0 GL	218	delete_gpio_led(&priv->leds[count]);
04553e92	219	return ERR_PTR(-ENODEV);
a314c5c0	220	}
a7d878af	221
a314c5c0 GL	222	static const struct of_device_id of_gpio_leds_match[] = {
	223	{ .compatible = "gpio-leds", },
	224	{},
	225	};
2bcc7ed5	226	#else /* CONFIG_OF_GPIO */
98ea1ea2	227	static struct gpio_leds_priv gpio_leds_create_of(struct platform_device pdev)
a314c5c0	228	{
04553e92	229	return ERR_PTR(-ENODEV);
a314c5c0	230	}
2bcc7ed5	231	#endif /* CONFIG_OF_GPIO */
a7d878af	232
a314c5c0	233
98ea1ea2	234	static int gpio_led_probe(struct platform_device *pdev)
a314c5c0 GL	235	{
	236	struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
	237	struct gpio_leds_priv *priv;
8fe4554f	238	struct pinctrl *pinctrl;
a314c5c0 GL	239	int i, ret = 0;
a314c5c0 GL	240
8fe4554f AC	241	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
	242	if (IS_ERR(pinctrl))
	243	dev_warn(&pdev->dev,
	244	"pins are not configured from the driver\n");
	245
a314c5c0	246	if (pdata && pdata->num_leds) {
198b8611 SK	247	priv = devm_kzalloc(&pdev->dev,
	248	sizeof_gpio_leds_priv(pdata->num_leds),
	249	GFP_KERNEL);
a314c5c0 GL	250	if (!priv)
	251	return -ENOMEM;
	252
	253	priv->num_leds = pdata->num_leds;
	254	for (i = 0; i < priv->num_leds; i++) {
	255	ret = create_gpio_led(&pdata->leds[i],
	256	&priv->leds[i],
	257	&pdev->dev, pdata->gpio_blink_set);
	258	if (ret < 0) {
	259	/* On failure: unwind the led creations */
	260	for (i = i - 1; i >= 0; i--)
	261	delete_gpio_led(&priv->leds[i]);
a314c5c0 GL	262	return ret;
	263	}
	264	}
	265	} else {
	266	priv = gpio_leds_create_of(pdev);
04553e92 RS	267	if (IS_ERR(priv))
04553e92 RS	268	return PTR_ERR(priv);
a314c5c0 GL	269	}
	270
	271	platform_set_drvdata(pdev, priv);
	272
	273	return 0;
a7d878af TP	274	}
a7d878af TP	275
678e8a6b	276	static int gpio_led_remove(struct platform_device *pdev)
a7d878af	277	{
59c4dce1	278	struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
a7d878af TP	279	int i;
a7d878af TP	280
a314c5c0 GL	281	for (i = 0; i < priv->num_leds; i++)
a314c5c0 GL	282	delete_gpio_led(&priv->leds[i]);
a7d878af	283
59c4dce1	284	platform_set_drvdata(pdev, NULL);
a7d878af TP	285
	286	return 0;
	287	}
	288
a314c5c0 GL	289	static struct platform_driver gpio_led_driver = {
a314c5c0 GL	290	.probe = gpio_led_probe,
df07cf81	291	.remove = gpio_led_remove,
a314c5c0 GL	292	.driver = {
	293	.name = "leds-gpio",
	294	.owner = THIS_MODULE,
6ebcebdd	295	.of_match_table = of_match_ptr(of_gpio_leds_match),
a7d878af	296	},
a7d878af	297	};
a314c5c0	298
892a8843	299	module_platform_driver(gpio_led_driver);
a7d878af TP	300
a7d878af TP	301	MODULE_AUTHOR("Raphael Assenat <[email protected]>, Trent Piepho <[email protected]>");
22e03f3b RA	302	MODULE_DESCRIPTION("GPIO LED driver");
22e03f3b RA	303	MODULE_LICENSE("GPL");
892a8843	304	MODULE_ALIAS("platform:leds-gpio");