[deliverable/linux.git] / drivers / video / backlight / pwm_bl.c

/*
 * linux/drivers/video/backlight/pwm_bl.c
 *
 * simple PWM based backlight control, board code has to setup
 * 1) pin configuration so PWM waveforms can output
 * 2) platform_data being correctly configured
 *
 * 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/gpio.h>
#include <linux/of_gpio.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <linux/err.h>
#include <linux/pwm.h>
#include <linux/pwm_backlight.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>

struct pwm_bl_data {
	struct pwm_device	*pwm;
	struct device		*dev;
	unsigned int		period;
	unsigned int		lth_brightness;
	unsigned int		*levels;
	bool			enabled;
	struct regulator	*power_supply;
	int			enable_gpio;
	unsigned long		enable_gpio_flags;
	int			(*notify)(struct device *,
					  int brightness);
	void			(*notify_after)(struct device *,
					int brightness);
	int			(*check_fb)(struct device *, struct fb_info *);
	void			(*exit)(struct device *);
};

static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness,
				   int max)
{
	int duty_cycle, err;

	if (pb->enabled)
		return;

	if (pb->levels) {
		duty_cycle = pb->levels[brightness];
		max = pb->levels[max];
	} else {
		duty_cycle = brightness;
	}

	duty_cycle = (duty_cycle * (pb->period - pb->lth_brightness) / max) +
		     pb->lth_brightness;

	pwm_config(pb->pwm, duty_cycle, pb->period);

	err = regulator_enable(pb->power_supply);
	if (err < 0)
		dev_err(pb->dev, "failed to enable power supply\n");

	if (gpio_is_valid(pb->enable_gpio)) {
		if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
			gpio_set_value(pb->enable_gpio, 0);
		else
			gpio_set_value(pb->enable_gpio, 1);
	}

	pwm_enable(pb->pwm);
	pb->enabled = true;
}

static void pwm_backlight_power_off(struct pwm_bl_data *pb)
{
	if (!pb->enabled)
		return;

	pwm_config(pb->pwm, 0, pb->period);
	pwm_disable(pb->pwm);

	if (gpio_is_valid(pb->enable_gpio)) {
		if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
			gpio_set_value(pb->enable_gpio, 1);
		else
			gpio_set_value(pb->enable_gpio, 0);
	}

	regulator_disable(pb->power_supply);
	pb->enabled = false;
}

static int pwm_backlight_update_status(struct backlight_device *bl)
{
	struct pwm_bl_data *pb = bl_get_data(bl);
	int brightness = bl->props.brightness;
	int max = bl->props.max_brightness;

	if (bl->props.power != FB_BLANK_UNBLANK ||
	    bl->props.fb_blank != FB_BLANK_UNBLANK ||
	    bl->props.state & BL_CORE_FBBLANK)
		brightness = 0;

	if (pb->notify)
		brightness = pb->notify(pb->dev, brightness);

	if (brightness > 0)
		pwm_backlight_power_on(pb, brightness, max);
	else
		pwm_backlight_power_off(pb);

	if (pb->notify_after)
		pb->notify_after(pb->dev, brightness);

	return 0;
}

static int pwm_backlight_get_brightness(struct backlight_device *bl)
{
	return bl->props.brightness;
}

static int pwm_backlight_check_fb(struct backlight_device *bl,
				  struct fb_info *info)
{
	struct pwm_bl_data *pb = bl_get_data(bl);

	return !pb->check_fb || pb->check_fb(pb->dev, info);
}

static const struct backlight_ops pwm_backlight_ops = {
	.update_status	= pwm_backlight_update_status,
	.get_brightness	= pwm_backlight_get_brightness,
	.check_fb	= pwm_backlight_check_fb,
};

#ifdef CONFIG_OF
static int pwm_backlight_parse_dt(struct device *dev,
				  struct platform_pwm_backlight_data *data)
{
	struct device_node *node = dev->of_node;
	enum of_gpio_flags flags;
	struct property *prop;
	int length;
	u32 value;
	int ret;

	if (!node)
		return -ENODEV;

	memset(data, 0, sizeof(*data));

	/* determine the number of brightness levels */
	prop = of_find_property(node, "brightness-levels", &length);
	if (!prop)
		return -EINVAL;

	data->max_brightness = length / sizeof(u32);

	/* read brightness levels from DT property */
	if (data->max_brightness > 0) {
		size_t size = sizeof(*data->levels) * data->max_brightness;

		data->levels = devm_kzalloc(dev, size, GFP_KERNEL);
		if (!data->levels)
			return -ENOMEM;

		ret = of_property_read_u32_array(node, "brightness-levels",
						 data->levels,
						 data->max_brightness);
		if (ret < 0)
			return ret;

		ret = of_property_read_u32(node, "default-brightness-level",
					   &value);
		if (ret < 0)
			return ret;

		data->dft_brightness = value;
		data->max_brightness--;
	}

	data->enable_gpio = of_get_named_gpio_flags(node, "enable-gpios", 0,
						    &flags);
	if (data->enable_gpio == -EPROBE_DEFER)
		return -EPROBE_DEFER;

	if (gpio_is_valid(data->enable_gpio) && (flags & OF_GPIO_ACTIVE_LOW))
		data->enable_gpio_flags |= PWM_BACKLIGHT_GPIO_ACTIVE_LOW;

	return 0;
}

static struct of_device_id pwm_backlight_of_match[] = {
	{ .compatible = "pwm-backlight" },
	{ }
};

MODULE_DEVICE_TABLE(of, pwm_backlight_of_match);
#else
static int pwm_backlight_parse_dt(struct device *dev,
				  struct platform_pwm_backlight_data *data)
{
	return -ENODEV;
}
#endif

static int pwm_backlight_probe(struct platform_device *pdev)
{
	struct platform_pwm_backlight_data *data = pdev->dev.platform_data;
	struct platform_pwm_backlight_data defdata;
	struct backlight_properties props;
	struct backlight_device *bl;
	struct pwm_bl_data *pb;
	unsigned int max;
	int ret;

	if (!data) {
		ret = pwm_backlight_parse_dt(&pdev->dev, &defdata);
		if (ret < 0) {
			dev_err(&pdev->dev, "failed to find platform data\n");
			return ret;
		}

		data = &defdata;
	}

	if (data->init) {
		ret = data->init(&pdev->dev);
		if (ret < 0)
			return ret;
	}

	pb = devm_kzalloc(&pdev->dev, sizeof(*pb), GFP_KERNEL);
	if (!pb) {
		dev_err(&pdev->dev, "no memory for state\n");
		ret = -ENOMEM;
		goto err_alloc;
	}

	if (data->levels) {
		max = data->levels[data->max_brightness];
		pb->levels = data->levels;
	} else
		max = data->max_brightness;

	pb->enable_gpio = data->enable_gpio;
	pb->enable_gpio_flags = data->enable_gpio_flags;
	pb->notify = data->notify;
	pb->notify_after = data->notify_after;
	pb->check_fb = data->check_fb;
	pb->exit = data->exit;
	pb->dev = &pdev->dev;
	pb->enabled = false;

	if (gpio_is_valid(pb->enable_gpio)) {
		unsigned long flags;

		if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
			flags = GPIOF_OUT_INIT_HIGH;
		else
			flags = GPIOF_OUT_INIT_LOW;

		ret = gpio_request_one(pb->enable_gpio, flags, "enable");
		if (ret < 0) {
			dev_err(&pdev->dev, "failed to request GPIO#%d: %d\n",
				pb->enable_gpio, ret);
			goto err_alloc;
		}
	}

	pb->power_supply = devm_regulator_get(&pdev->dev, "power");
	if (IS_ERR(pb->power_supply)) {
		ret = PTR_ERR(pb->power_supply);
		goto err_gpio;
	}

	pb->pwm = devm_pwm_get(&pdev->dev, NULL);
	if (IS_ERR(pb->pwm)) {
		dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");

		pb->pwm = pwm_request(data->pwm_id, "pwm-backlight");
		if (IS_ERR(pb->pwm)) {
			dev_err(&pdev->dev, "unable to request legacy PWM\n");
			ret = PTR_ERR(pb->pwm);
			goto err_gpio;
		}
	}

	dev_dbg(&pdev->dev, "got pwm for backlight\n");

	/*
	 * The DT case will set the pwm_period_ns field to 0 and store the
	 * period, parsed from the DT, in the PWM device. For the non-DT case,
	 * set the period from platform data.
	 */
	if (data->pwm_period_ns > 0)
		pwm_set_period(pb->pwm, data->pwm_period_ns);

	pb->period = pwm_get_period(pb->pwm);
	pb->lth_brightness = data->lth_brightness * (pb->period / max);

	memset(&props, 0, sizeof(struct backlight_properties));
	props.type = BACKLIGHT_RAW;
	props.max_brightness = data->max_brightness;
	bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, pb,
				       &pwm_backlight_ops, &props);
	if (IS_ERR(bl)) {
		dev_err(&pdev->dev, "failed to register backlight\n");
		ret = PTR_ERR(bl);
		goto err_gpio;
	}

	if (data->dft_brightness > data->max_brightness) {
		dev_warn(&pdev->dev,
			 "invalid default brightness level: %u, using %u\n",
			 data->dft_brightness, data->max_brightness);
		data->dft_brightness = data->max_brightness;
	}

	bl->props.brightness = data->dft_brightness;
	backlight_update_status(bl);

	platform_set_drvdata(pdev, bl);
	return 0;

err_gpio:
	if (gpio_is_valid(pb->enable_gpio))
		gpio_free(pb->enable_gpio);
err_alloc:
	if (data->exit)
		data->exit(&pdev->dev);
	return ret;
}

static int pwm_backlight_remove(struct platform_device *pdev)
{
	struct backlight_device *bl = platform_get_drvdata(pdev);
	struct pwm_bl_data *pb = bl_get_data(bl);

	backlight_device_unregister(bl);
	pwm_backlight_power_off(pb);

	if (pb->exit)
		pb->exit(&pdev->dev);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int pwm_backlight_suspend(struct device *dev)
{
	struct backlight_device *bl = dev_get_drvdata(dev);
	struct pwm_bl_data *pb = bl_get_data(bl);

	if (pb->notify)
		pb->notify(pb->dev, 0);

	pwm_backlight_power_off(pb);

	if (pb->notify_after)
		pb->notify_after(pb->dev, 0);

	return 0;
}

static int pwm_backlight_resume(struct device *dev)
{
	struct backlight_device *bl = dev_get_drvdata(dev);

	backlight_update_status(bl);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(pwm_backlight_pm_ops, pwm_backlight_suspend,
			 pwm_backlight_resume);

static struct platform_driver pwm_backlight_driver = {
	.driver		= {
		.name		= "pwm-backlight",
		.owner		= THIS_MODULE,
		.pm		= &pwm_backlight_pm_ops,
		.of_match_table	= of_match_ptr(pwm_backlight_of_match),
	},
	.probe		= pwm_backlight_probe,
	.remove		= pwm_backlight_remove,
};

module_platform_driver(pwm_backlight_driver);

MODULE_DESCRIPTION("PWM based Backlight Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pwm-backlight");
Commit	Line	Data
42796d37	1	/*
	2	* linux/drivers/video/backlight/pwm_bl.c
	3	*
	4	* simple PWM based backlight control, board code has to setup
	5	* 1) pin configuration so PWM waveforms can output
b8cdd877	6	* 2) platform_data being correctly configured
42796d37	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
8265b2e4 TR	13	#include <linux/gpio.h>
8265b2e4 TR	14	#include <linux/of_gpio.h>
42796d37	15	#include <linux/module.h>
	16	#include <linux/kernel.h>
	17	#include <linux/init.h>
	18	#include <linux/platform_device.h>
	19	#include <linux/fb.h>
	20	#include <linux/backlight.h>
	21	#include <linux/err.h>
	22	#include <linux/pwm.h>
	23	#include <linux/pwm_backlight.h>
22ceeee1	24	#include <linux/regulator/consumer.h>
5a0e3ad6	25	#include <linux/slab.h>
42796d37	26
	27	struct pwm_bl_data {
	28	struct pwm_device *pwm;
cfc3899f	29	struct device *dev;
42796d37	30	unsigned int period;
fef7764f	31	unsigned int lth_brightness;
3e3ed6cd	32	unsigned int *levels;
97c38437	33	bool enabled;
22ceeee1	34	struct regulator *power_supply;
8265b2e4 TR	35	int enable_gpio;
8265b2e4 TR	36	unsigned long enable_gpio_flags;
cfc3899f BD	37	int (notify)(struct device ,
cfc3899f BD	38	int brightness);
cc7993f6 DL	39	void (notify_after)(struct device ,
cc7993f6 DL	40	int brightness);
ef0a5e80	41	int (check_fb)(struct device , struct fb_info *);
3e3ed6cd	42	void (exit)(struct device );
42796d37	43	};
42796d37	44
62b744a8 TR	45	static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness,
	46	int max)
	47	{
	48	int duty_cycle, err;
	49
97c38437 TR	50	if (pb->enabled)
	51	return;
	52
62b744a8 TR	53	if (pb->levels) {
	54	duty_cycle = pb->levels[brightness];
	55	max = pb->levels[max];
	56	} else {
	57	duty_cycle = brightness;
	58	}
	59
	60	duty_cycle = (duty_cycle * (pb->period - pb->lth_brightness) / max) +
	61	pb->lth_brightness;
	62
	63	pwm_config(pb->pwm, duty_cycle, pb->period);
8265b2e4	64
22ceeee1 TR	65	err = regulator_enable(pb->power_supply);
	66	if (err < 0)
	67	dev_err(pb->dev, "failed to enable power supply\n");
	68
8265b2e4 TR	69	if (gpio_is_valid(pb->enable_gpio)) {
	70	if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
	71	gpio_set_value(pb->enable_gpio, 0);
	72	else
	73	gpio_set_value(pb->enable_gpio, 1);
	74	}
	75
62b744a8	76	pwm_enable(pb->pwm);
97c38437	77	pb->enabled = true;
62b744a8 TR	78	}
	79
	80	static void pwm_backlight_power_off(struct pwm_bl_data *pb)
	81	{
97c38437 TR	82	if (!pb->enabled)
	83	return;
	84
62b744a8 TR	85	pwm_config(pb->pwm, 0, pb->period);
62b744a8 TR	86	pwm_disable(pb->pwm);
97c38437	87
8265b2e4 TR	88	if (gpio_is_valid(pb->enable_gpio)) {
	89	if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
	90	gpio_set_value(pb->enable_gpio, 1);
	91	else
	92	gpio_set_value(pb->enable_gpio, 0);
	93	}
	94
22ceeee1	95	regulator_disable(pb->power_supply);
97c38437	96	pb->enabled = false;
62b744a8 TR	97	}
62b744a8 TR	98
42796d37	99	static int pwm_backlight_update_status(struct backlight_device *bl)
42796d37	100	{
e6e3dbf9	101	struct pwm_bl_data *pb = bl_get_data(bl);
42796d37	102	int brightness = bl->props.brightness;
	103	int max = bl->props.max_brightness;
	104
0132267d AC	105	if (bl->props.power != FB_BLANK_UNBLANK \|\|
	106	bl->props.fb_blank != FB_BLANK_UNBLANK \|\|
	107	bl->props.state & BL_CORE_FBBLANK)
42796d37	108	brightness = 0;
42796d37	109
3b73125a	110	if (pb->notify)
cfc3899f	111	brightness = pb->notify(pb->dev, brightness);
3b73125a	112
62b744a8 TR	113	if (brightness > 0)
	114	pwm_backlight_power_on(pb, brightness, max);
	115	else
	116	pwm_backlight_power_off(pb);
cc7993f6 DL	117
	118	if (pb->notify_after)
	119	pb->notify_after(pb->dev, brightness);
	120
42796d37	121	return 0;
	122	}
	123
	124	static int pwm_backlight_get_brightness(struct backlight_device *bl)
	125	{
	126	return bl->props.brightness;
	127	}
	128
ef0a5e80 RM	129	static int pwm_backlight_check_fb(struct backlight_device *bl,
	130	struct fb_info *info)
	131	{
e6e3dbf9	132	struct pwm_bl_data *pb = bl_get_data(bl);
ef0a5e80 RM	133
	134	return !pb->check_fb \|\| pb->check_fb(pb->dev, info);
	135	}
	136
9905a43b	137	static const struct backlight_ops pwm_backlight_ops = {
42796d37	138	.update_status = pwm_backlight_update_status,
42796d37	139	.get_brightness = pwm_backlight_get_brightness,
ef0a5e80	140	.check_fb = pwm_backlight_check_fb,
42796d37	141	};
42796d37	142
3e3ed6cd TR	143	#ifdef CONFIG_OF
	144	static int pwm_backlight_parse_dt(struct device *dev,
	145	struct platform_pwm_backlight_data *data)
	146	{
	147	struct device_node *node = dev->of_node;
8265b2e4	148	enum of_gpio_flags flags;
3e3ed6cd TR	149	struct property *prop;
	150	int length;
	151	u32 value;
	152	int ret;
	153
	154	if (!node)
	155	return -ENODEV;
	156
	157	memset(data, 0, sizeof(*data));
	158
	159	/* determine the number of brightness levels */
	160	prop = of_find_property(node, "brightness-levels", &length);
	161	if (!prop)
	162	return -EINVAL;
	163
	164	data->max_brightness = length / sizeof(u32);
	165
	166	/* read brightness levels from DT property */
	167	if (data->max_brightness > 0) {
	168	size_t size = sizeof(data->levels) data->max_brightness;
	169
	170	data->levels = devm_kzalloc(dev, size, GFP_KERNEL);
	171	if (!data->levels)
	172	return -ENOMEM;
	173
	174	ret = of_property_read_u32_array(node, "brightness-levels",
	175	data->levels,
	176	data->max_brightness);
	177	if (ret < 0)
	178	return ret;
	179
	180	ret = of_property_read_u32(node, "default-brightness-level",
	181	&value);
	182	if (ret < 0)
	183	return ret;
	184
3e3ed6cd TR	185	data->dft_brightness = value;
	186	data->max_brightness--;
	187	}
	188
8265b2e4 TR	189	data->enable_gpio = of_get_named_gpio_flags(node, "enable-gpios", 0,
	190	&flags);
	191	if (data->enable_gpio == -EPROBE_DEFER)
	192	return -EPROBE_DEFER;
	193
	194	if (gpio_is_valid(data->enable_gpio) && (flags & OF_GPIO_ACTIVE_LOW))
	195	data->enable_gpio_flags \|= PWM_BACKLIGHT_GPIO_ACTIVE_LOW;
3e3ed6cd TR	196
	197	return 0;
	198	}
	199
	200	static struct of_device_id pwm_backlight_of_match[] = {
	201	{ .compatible = "pwm-backlight" },
	202	{ }
	203	};
	204
	205	MODULE_DEVICE_TABLE(of, pwm_backlight_of_match);
	206	#else
	207	static int pwm_backlight_parse_dt(struct device *dev,
	208	struct platform_pwm_backlight_data *data)
	209	{
	210	return -ENODEV;
	211	}
	212	#endif
	213
42796d37	214	static int pwm_backlight_probe(struct platform_device *pdev)
	215	{
	216	struct platform_pwm_backlight_data *data = pdev->dev.platform_data;
3e3ed6cd TR	217	struct platform_pwm_backlight_data defdata;
3e3ed6cd TR	218	struct backlight_properties props;
42796d37	219	struct backlight_device *bl;
42796d37	220	struct pwm_bl_data *pb;
3e3ed6cd	221	unsigned int max;
3b73125a	222	int ret;
42796d37	223
14563a4e	224	if (!data) {
3e3ed6cd TR	225	ret = pwm_backlight_parse_dt(&pdev->dev, &defdata);
	226	if (ret < 0) {
	227	dev_err(&pdev->dev, "failed to find platform data\n");
	228	return ret;
	229	}
	230
	231	data = &defdata;
14563a4e	232	}
42796d37	233
3b73125a PZ	234	if (data->init) {
	235	ret = data->init(&pdev->dev);
	236	if (ret < 0)
	237	return ret;
	238	}
	239
ce969228	240	pb = devm_kzalloc(&pdev->dev, sizeof(*pb), GFP_KERNEL);
3b73125a	241	if (!pb) {
14563a4e	242	dev_err(&pdev->dev, "no memory for state\n");
3b73125a PZ	243	ret = -ENOMEM;
	244	goto err_alloc;
	245	}
42796d37	246
3e3ed6cd TR	247	if (data->levels) {
	248	max = data->levels[data->max_brightness];
	249	pb->levels = data->levels;
	250	} else
	251	max = data->max_brightness;
	252
8265b2e4 TR	253	pb->enable_gpio = data->enable_gpio;
8265b2e4 TR	254	pb->enable_gpio_flags = data->enable_gpio_flags;
3b73125a	255	pb->notify = data->notify;
cc7993f6	256	pb->notify_after = data->notify_after;
ef0a5e80	257	pb->check_fb = data->check_fb;
3e3ed6cd	258	pb->exit = data->exit;
cfc3899f	259	pb->dev = &pdev->dev;
97c38437	260	pb->enabled = false;
42796d37	261
8265b2e4 TR	262	if (gpio_is_valid(pb->enable_gpio)) {
	263	unsigned long flags;
	264
	265	if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
	266	flags = GPIOF_OUT_INIT_HIGH;
	267	else
	268	flags = GPIOF_OUT_INIT_LOW;
	269
	270	ret = gpio_request_one(pb->enable_gpio, flags, "enable");
	271	if (ret < 0) {
	272	dev_err(&pdev->dev, "failed to request GPIO#%d: %d\n",
	273	pb->enable_gpio, ret);
	274	goto err_alloc;
	275	}
	276	}
	277
22ceeee1 TR	278	pb->power_supply = devm_regulator_get(&pdev->dev, "power");
	279	if (IS_ERR(pb->power_supply)) {
	280	ret = PTR_ERR(pb->power_supply);
	281	goto err_gpio;
	282	}
	283
60ce7028	284	pb->pwm = devm_pwm_get(&pdev->dev, NULL);
43bda1a6	285	if (IS_ERR(pb->pwm)) {
3e3ed6cd TR	286	dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
	287
	288	pb->pwm = pwm_request(data->pwm_id, "pwm-backlight");
	289	if (IS_ERR(pb->pwm)) {
	290	dev_err(&pdev->dev, "unable to request legacy PWM\n");
	291	ret = PTR_ERR(pb->pwm);
8265b2e4	292	goto err_gpio;
3e3ed6cd TR	293	}
	294	}
	295
	296	dev_dbg(&pdev->dev, "got pwm for backlight\n");
	297
	298	/*
	299	* The DT case will set the pwm_period_ns field to 0 and store the
	300	* period, parsed from the DT, in the PWM device. For the non-DT case,
	301	* set the period from platform data.
	302	*/
	303	if (data->pwm_period_ns > 0)
	304	pwm_set_period(pb->pwm, data->pwm_period_ns);
	305
	306	pb->period = pwm_get_period(pb->pwm);
	307	pb->lth_brightness = data->lth_brightness * (pb->period / max);
42796d37	308
a19a6ee6	309	memset(&props, 0, sizeof(struct backlight_properties));
bb7ca747	310	props.type = BACKLIGHT_RAW;
a19a6ee6 MG	311	props.max_brightness = data->max_brightness;
	312	bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, pb,
	313	&pwm_backlight_ops, &props);
42796d37	314	if (IS_ERR(bl)) {
42796d37	315	dev_err(&pdev->dev, "failed to register backlight\n");
3b73125a	316	ret = PTR_ERR(bl);
8265b2e4	317	goto err_gpio;
42796d37	318	}
42796d37	319
83cfd726 PU	320	if (data->dft_brightness > data->max_brightness) {
	321	dev_warn(&pdev->dev,
	322	"invalid default brightness level: %u, using %u\n",
	323	data->dft_brightness, data->max_brightness);
	324	data->dft_brightness = data->max_brightness;
	325	}
	326
42796d37	327	bl->props.brightness = data->dft_brightness;
	328	backlight_update_status(bl);
	329
	330	platform_set_drvdata(pdev, bl);
	331	return 0;
3b73125a	332
8265b2e4 TR	333	err_gpio:
	334	if (gpio_is_valid(pb->enable_gpio))
	335	gpio_free(pb->enable_gpio);
3b73125a PZ	336	err_alloc:
	337	if (data->exit)
	338	data->exit(&pdev->dev);
	339	return ret;
42796d37	340	}
	341
	342	static int pwm_backlight_remove(struct platform_device *pdev)
	343	{
	344	struct backlight_device *bl = platform_get_drvdata(pdev);
e6e3dbf9	345	struct pwm_bl_data *pb = bl_get_data(bl);
42796d37	346
42796d37	347	backlight_device_unregister(bl);
62b744a8	348	pwm_backlight_power_off(pb);
668e63c6	349
3e3ed6cd TR	350	if (pb->exit)
3e3ed6cd TR	351	pb->exit(&pdev->dev);
668e63c6	352
42796d37	353	return 0;
	354	}
	355
c791126b	356	#ifdef CONFIG_PM_SLEEP
e2c17bc6	357	static int pwm_backlight_suspend(struct device *dev)
42796d37	358	{
e2c17bc6	359	struct backlight_device *bl = dev_get_drvdata(dev);
e6e3dbf9	360	struct pwm_bl_data *pb = bl_get_data(bl);
42796d37	361
82e8b542	362	if (pb->notify)
cfc3899f	363	pb->notify(pb->dev, 0);
668e63c6	364
62b744a8	365	pwm_backlight_power_off(pb);
668e63c6	366
cc7993f6 DL	367	if (pb->notify_after)
cc7993f6 DL	368	pb->notify_after(pb->dev, 0);
668e63c6	369
42796d37	370	return 0;
	371	}
	372
e2c17bc6	373	static int pwm_backlight_resume(struct device *dev)
42796d37	374	{
e2c17bc6	375	struct backlight_device *bl = dev_get_drvdata(dev);
42796d37	376
42796d37	377	backlight_update_status(bl);
668e63c6	378
42796d37	379	return 0;
42796d37	380	}
c791126b	381	#endif
e2c17bc6 MB	382
	383	static SIMPLE_DEV_PM_OPS(pwm_backlight_pm_ops, pwm_backlight_suspend,
	384	pwm_backlight_resume);
	385
42796d37	386	static struct platform_driver pwm_backlight_driver = {
42796d37	387	.driver = {
3e3ed6cd TR	388	.name = "pwm-backlight",
3e3ed6cd TR	389	.owner = THIS_MODULE,
3e3ed6cd	390	.pm = &pwm_backlight_pm_ops,
3e3ed6cd	391	.of_match_table = of_match_ptr(pwm_backlight_of_match),
42796d37	392	},
	393	.probe = pwm_backlight_probe,
	394	.remove = pwm_backlight_remove,
42796d37	395	};
42796d37	396
81178e02	397	module_platform_driver(pwm_backlight_driver);
42796d37	398
	399	MODULE_DESCRIPTION("PWM based Backlight Driver");
	400	MODULE_LICENSE("GPL");
8cd68198	401	MODULE_ALIAS("platform:pwm-backlight");