[linux-2.6-block.git] / drivers / leds / leds-gpio.c

/*
 * LEDs driver for GPIOs
 *
 * Copyright (C) 2007 8D Technologies inc.
 * Raphael Assenat <raph@8d.com>
 * 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/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 <asm/gpio.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 __devinit 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)) {
		printk(KERN_INFO "Skipping unavailable LED gpio %d (%s)\n",
				template->gpio, template->name);
		return 0;
	}

	ret = gpio_request(template->gpio, template->name);
	if (ret < 0)
		return ret;

	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 = gpio_direction_output(led_dat->gpio, led_dat->active_low ^ state);
	if (ret < 0)
		goto err;
		
	INIT_WORK(&led_dat->work, gpio_led_work);

	ret = led_classdev_register(parent, &led_dat->cdev);
	if (ret < 0)
		goto err;

	return 0;
err:
	gpio_free(led_dat->gpio);
	return ret;
}

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);
	gpio_free(led->gpio);
}

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 * __devinit gpio_leds_create_of(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node, *child;
	struct gpio_leds_priv *priv;
	int count = 0, ret;

	/* count LEDs in this device, so we know how much to allocate */
	for_each_child_of_node(np, child)
		count++;
	if (!count)
		return NULL;

	priv = kzalloc(sizeof_gpio_leds_priv(count), GFP_KERNEL);
	if (!priv)
		return NULL;

	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]);
	kfree(priv);
	return NULL;
}

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


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

	if (pdata && pdata->num_leds) {
		priv = kzalloc(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]);
				kfree(priv);
				return ret;
			}
		}
	} else {
		priv = gpio_leds_create_of(pdev);
		if (!priv)
			return -ENODEV;
	}

	platform_set_drvdata(pdev, priv);

	return 0;
}

static int __devexit gpio_led_remove(struct platform_device *pdev)
{
	struct gpio_leds_priv *priv = dev_get_drvdata(&pdev->dev);
	int i;

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

	dev_set_drvdata(&pdev->dev, NULL);
	kfree(priv);

	return 0;
}

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

MODULE_ALIAS("platform:leds-gpio");

static int __init gpio_led_init(void)
{
	return platform_driver_register(&gpio_led_driver);
}

static void __exit gpio_led_exit(void)
{
	platform_driver_unregister(&gpio_led_driver);
}

module_init(gpio_led_init);
module_exit(gpio_led_exit);

MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
MODULE_DESCRIPTION("GPIO LED driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
22e03f3b RA	1	/*
	2	* LEDs driver for GPIOs
	3	*
	4	* Copyright (C) 2007 8D Technologies inc.
	5	* Raphael Assenat <raph@8d.com>
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>
	16	#include <linux/leds.h>
a314c5c0 GL	17	#include <linux/of_platform.h>
a314c5c0 GL	18	#include <linux/of_gpio.h>
5a0e3ad6	19	#include <linux/slab.h>
00852279	20	#include <linux/workqueue.h>
54f4dedb	21	#include <linux/module.h>
00852279	22
22e03f3b RA	23	#include <asm/gpio.h>
	24
	25	struct gpio_led_data {
	26	struct led_classdev cdev;
	27	unsigned gpio;
00852279 DB	28	struct work_struct work;
	29	u8 new_level;
	30	u8 can_sleep;
22e03f3b	31	u8 active_low;
2146325d BH	32	u8 blinking;
2146325d BH	33	int (*platform_gpio_blink_set)(unsigned gpio, int state,
ca3259b3	34	unsigned long delay_on, unsigned long delay_off);
22e03f3b RA	35	};
22e03f3b RA	36
00852279 DB	37	static void gpio_led_work(struct work_struct *work)
	38	{
	39	struct gpio_led_data *led_dat =
	40	container_of(work, struct gpio_led_data, work);
	41
2146325d BH	42	if (led_dat->blinking) {
	43	led_dat->platform_gpio_blink_set(led_dat->gpio,
	44	led_dat->new_level,
	45	NULL, NULL);
	46	led_dat->blinking = 0;
	47	} else
	48	gpio_set_value_cansleep(led_dat->gpio, led_dat->new_level);
00852279	49	}
22e03f3b RA	50
	51	static void gpio_led_set(struct led_classdev *led_cdev,
	52	enum led_brightness value)
	53	{
	54	struct gpio_led_data *led_dat =
	55	container_of(led_cdev, struct gpio_led_data, cdev);
	56	int level;
	57
	58	if (value == LED_OFF)
	59	level = 0;
	60	else
	61	level = 1;
	62
	63	if (led_dat->active_low)
	64	level = !level;
	65
306dd85c DB	66	/* Setting GPIOs with I2C/etc requires a task context, and we don't
	67	* seem to have a reliable way to know if we're already in one; so
	68	* let's just assume the worst.
	69	*/
00852279	70	if (led_dat->can_sleep) {
306dd85c DB	71	led_dat->new_level = level;
306dd85c DB	72	schedule_work(&led_dat->work);
2146325d BH	73	} else {
	74	if (led_dat->blinking) {
	75	led_dat->platform_gpio_blink_set(led_dat->gpio, level,
	76	NULL, NULL);
	77	led_dat->blinking = 0;
	78	} else
	79	gpio_set_value(led_dat->gpio, level);
	80	}
22e03f3b RA	81	}
22e03f3b RA	82
ca3259b3 HVR	83	static int gpio_blink_set(struct led_classdev *led_cdev,
	84	unsigned long delay_on, unsigned long delay_off)
	85	{
	86	struct gpio_led_data *led_dat =
	87	container_of(led_cdev, struct gpio_led_data, cdev);
	88
2146325d BH	89	led_dat->blinking = 1;
	90	return led_dat->platform_gpio_blink_set(led_dat->gpio, GPIO_LED_BLINK,
	91	delay_on, delay_off);
ca3259b3 HVR	92	}
ca3259b3 HVR	93
a7d878af TP	94	static int __devinit create_gpio_led(const struct gpio_led *template,
a7d878af TP	95	struct gpio_led_data led_dat, struct device parent,
2146325d	96	int (blink_set)(unsigned, int, unsigned long , unsigned long *))
a7d878af	97	{
ed88bae6	98	int ret, state;
a7d878af	99
0b4634fc DES	100	led_dat->gpio = -1;
0b4634fc DES	101
d379ee8a DB	102	/* skip leds that aren't available */
d379ee8a DB	103	if (!gpio_is_valid(template->gpio)) {
2fea0922	104	printk(KERN_INFO "Skipping unavailable LED gpio %d (%s)\n",
d379ee8a	105	template->gpio, template->name);
ac15e950	106	return 0;
d379ee8a DB	107	}
d379ee8a DB	108
a7d878af TP	109	ret = gpio_request(template->gpio, template->name);
	110	if (ret < 0)
	111	return ret;
	112
	113	led_dat->cdev.name = template->name;
	114	led_dat->cdev.default_trigger = template->default_trigger;
	115	led_dat->gpio = template->gpio;
	116	led_dat->can_sleep = gpio_cansleep(template->gpio);
	117	led_dat->active_low = template->active_low;
2146325d	118	led_dat->blinking = 0;
a7d878af TP	119	if (blink_set) {
	120	led_dat->platform_gpio_blink_set = blink_set;
	121	led_dat->cdev.blink_set = gpio_blink_set;
	122	}
	123	led_dat->cdev.brightness_set = gpio_led_set;
ed88bae6	124	if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP)
dabc69c2	125	state = !!gpio_get_value_cansleep(led_dat->gpio) ^ led_dat->active_low;
ed88bae6 TP	126	else
	127	state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
	128	led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
defb512d RP	129	if (!template->retain_state_suspended)
defb512d RP	130	led_dat->cdev.flags \|= LED_CORE_SUSPENDRESUME;
a7d878af	131
ed88bae6	132	ret = gpio_direction_output(led_dat->gpio, led_dat->active_low ^ state);
a7d878af TP	133	if (ret < 0)
a7d878af TP	134	goto err;
2146325d	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)
	140	goto err;
	141
	142	return 0;
	143	err:
	144	gpio_free(led_dat->gpio);
	145	return ret;
	146	}
	147
	148	static void delete_gpio_led(struct gpio_led_data *led)
	149	{
d379ee8a DB	150	if (!gpio_is_valid(led->gpio))
d379ee8a DB	151	return;
a7d878af TP	152	led_classdev_unregister(&led->cdev);
	153	cancel_work_sync(&led->work);
	154	gpio_free(led->gpio);
	155	}
	156
a314c5c0 GL	157	struct gpio_leds_priv {
	158	int num_leds;
	159	struct gpio_led_data leds[];
	160	};
22e03f3b	161
a314c5c0	162	static inline int sizeof_gpio_leds_priv(int num_leds)
22e03f3b	163	{
a314c5c0 GL	164	return sizeof(struct gpio_leds_priv) +
a314c5c0 GL	165	(sizeof(struct gpio_led_data) * num_leds);
22e03f3b RA	166	}
22e03f3b RA	167
a7d878af	168	/* Code to create from OpenFirmware platform devices */
2bcc7ed5	169	#ifdef CONFIG_OF_GPIO
a314c5c0	170	static struct gpio_leds_priv * __devinit gpio_leds_create_of(struct platform_device *pdev)
a7d878af	171	{
a314c5c0 GL	172	struct device_node np = pdev->dev.of_node, child;
a314c5c0 GL	173	struct gpio_leds_priv *priv;
a7d878af TP	174	int count = 0, ret;
a7d878af TP	175
a314c5c0	176	/* count LEDs in this device, so we know how much to allocate */
a7d878af TP	177	for_each_child_of_node(np, child)
	178	count++;
	179	if (!count)
a314c5c0	180	return NULL;
a7d878af	181
a314c5c0 GL	182	priv = kzalloc(sizeof_gpio_leds_priv(count), GFP_KERNEL);
	183	if (!priv)
	184	return NULL;
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--)
	218	delete_gpio_led(&priv->leds[count]);
	219	kfree(priv);
	220	return NULL;
	221	}
a7d878af	222
a314c5c0 GL	223	static const struct of_device_id of_gpio_leds_match[] = {
	224	{ .compatible = "gpio-leds", },
	225	{},
	226	};
2bcc7ed5	227	#else /* CONFIG_OF_GPIO */
a314c5c0 GL	228	static struct gpio_leds_priv * __devinit gpio_leds_create_of(struct platform_device *pdev)
	229	{
	230	return NULL;
	231	}
	232	#define of_gpio_leds_match NULL
2bcc7ed5	233	#endif /* CONFIG_OF_GPIO */
a7d878af	234
a314c5c0 GL	235
	236	static int __devinit gpio_led_probe(struct platform_device *pdev)
	237	{
	238	struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
	239	struct gpio_leds_priv *priv;
	240	int i, ret = 0;
	241
	242	if (pdata && pdata->num_leds) {
	243	priv = kzalloc(sizeof_gpio_leds_priv(pdata->num_leds),
	244	GFP_KERNEL);
	245	if (!priv)
	246	return -ENOMEM;
	247
	248	priv->num_leds = pdata->num_leds;
	249	for (i = 0; i < priv->num_leds; i++) {
	250	ret = create_gpio_led(&pdata->leds[i],
	251	&priv->leds[i],
	252	&pdev->dev, pdata->gpio_blink_set);
	253	if (ret < 0) {
	254	/* On failure: unwind the led creations */
	255	for (i = i - 1; i >= 0; i--)
	256	delete_gpio_led(&priv->leds[i]);
	257	kfree(priv);
	258	return ret;
	259	}
	260	}
	261	} else {
	262	priv = gpio_leds_create_of(pdev);
	263	if (!priv)
	264	return -ENODEV;
	265	}
	266
	267	platform_set_drvdata(pdev, priv);
	268
	269	return 0;
a7d878af TP	270	}
a7d878af TP	271
a314c5c0	272	static int __devexit gpio_led_remove(struct platform_device *pdev)
a7d878af	273	{
a314c5c0	274	struct gpio_leds_priv *priv = dev_get_drvdata(&pdev->dev);
a7d878af TP	275	int i;
a7d878af TP	276
a314c5c0 GL	277	for (i = 0; i < priv->num_leds; i++)
a314c5c0 GL	278	delete_gpio_led(&priv->leds[i]);
a7d878af	279
a314c5c0 GL	280	dev_set_drvdata(&pdev->dev, NULL);
a314c5c0 GL	281	kfree(priv);
a7d878af TP	282
	283	return 0;
	284	}
	285
a314c5c0 GL	286	static struct platform_driver gpio_led_driver = {
	287	.probe = gpio_led_probe,
	288	.remove = __devexit_p(gpio_led_remove),
	289	.driver = {
	290	.name = "leds-gpio",
	291	.owner = THIS_MODULE,
4018294b	292	.of_match_table = of_gpio_leds_match,
a7d878af	293	},
a7d878af	294	};
a314c5c0 GL	295
a314c5c0 GL	296	MODULE_ALIAS("platform:leds-gpio");
a7d878af	297
b2bdc3e7	298	static int __init gpio_led_init(void)
a7d878af	299	{
a314c5c0	300	return platform_driver_register(&gpio_led_driver);
a7d878af	301	}
a7d878af	302
b2bdc3e7	303	static void __exit gpio_led_exit(void)
a7d878af	304	{
b2bdc3e7	305	platform_driver_unregister(&gpio_led_driver);
b2bdc3e7 RP	306	}
	307
	308	module_init(gpio_led_init);
	309	module_exit(gpio_led_exit);
a7d878af TP	310
a7d878af TP	311	MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
22e03f3b RA	312	MODULE_DESCRIPTION("GPIO LED driver");
22e03f3b RA	313	MODULE_LICENSE("GPL");