[deliverable/linux.git] / drivers / regulator / pwm-regulator.c

/*
 * Regulator driver for PWM Regulators
 *
 * Copyright (C) 2014 - STMicroelectronics Inc.
 *
 * Author: Lee Jones <lee.jones@linaro.org>
 *
 * 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/delay.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/pwm.h>
#include <linux/gpio/consumer.h>

struct pwm_regulator_data {
	/*  Shared */
	struct pwm_device *pwm;

	/* Voltage table */
	struct pwm_voltages *duty_cycle_table;

	/* regulator descriptor */
	struct regulator_desc desc;

	/* Regulator ops */
	struct regulator_ops ops;

	int state;

	/* Continuous voltage */
	int volt_uV;

	/* Enable GPIO */
	struct gpio_desc *enb_gpio;
};

struct pwm_voltages {
	unsigned int uV;
	unsigned int dutycycle;
};

/**
 * Voltage table call-backs
 */
static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);

	return drvdata->state;
}

static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
					 unsigned selector)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	struct pwm_args pargs;
	int dutycycle;
	int ret;

	pwm_get_args(drvdata->pwm, &pargs);

	dutycycle = (pargs.period *
		    drvdata->duty_cycle_table[selector].dutycycle) / 100;

	ret = pwm_config(drvdata->pwm, dutycycle, pargs.period);
	if (ret) {
		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
		return ret;
	}

	drvdata->state = selector;

	return 0;
}

static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
				      unsigned selector)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);

	if (selector >= rdev->desc->n_voltages)
		return -EINVAL;

	return drvdata->duty_cycle_table[selector].uV;
}

static int pwm_regulator_enable(struct regulator_dev *dev)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);

	if (drvdata->enb_gpio)
		gpiod_set_value_cansleep(drvdata->enb_gpio, 1);

	return pwm_enable(drvdata->pwm);
}

static int pwm_regulator_disable(struct regulator_dev *dev)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);

	pwm_disable(drvdata->pwm);

	if (drvdata->enb_gpio)
		gpiod_set_value_cansleep(drvdata->enb_gpio, 0);

	return 0;
}

static int pwm_regulator_is_enabled(struct regulator_dev *dev)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);

	if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
		return false;

	return pwm_is_enabled(drvdata->pwm);
}

static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);

	return drvdata->volt_uV;
}

static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
					int min_uV, int max_uV,
					unsigned *selector)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	unsigned int ramp_delay = rdev->constraints->ramp_delay;
	struct pwm_args pargs;
	unsigned int req_diff = min_uV - rdev->constraints->min_uV;
	unsigned int diff;
	unsigned int duty_pulse;
	u64 req_period;
	u32 rem;
	int old_uV = pwm_regulator_get_voltage(rdev);
	int ret;

	pwm_get_args(drvdata->pwm, &pargs);
	diff = rdev->constraints->max_uV - rdev->constraints->min_uV;

	/* First try to find out if we get the iduty cycle time which is
	 * factor of PWM period time. If (request_diff_to_min * pwm_period)
	 * is perfect divided by voltage_range_diff then it is possible to
	 * get duty cycle time which is factor of PWM period. This will help
	 * to get output voltage nearer to requested value as there is no
	 * calculation loss.
	 */
	req_period = req_diff * pargs.period;
	div_u64_rem(req_period, diff, &rem);
	if (!rem) {
		do_div(req_period, diff);
		duty_pulse = (unsigned int)req_period;
	} else {
		duty_pulse = (pargs.period / 100) * ((req_diff * 100) / diff);
	}

	ret = pwm_config(drvdata->pwm, duty_pulse, pargs.period);
	if (ret) {
		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
		return ret;
	}

	drvdata->volt_uV = min_uV;

	if ((ramp_delay == 0) || !pwm_regulator_is_enabled(rdev))
		return 0;

	/* Ramp delay is in uV/uS. Adjust to uS and delay */
	ramp_delay = DIV_ROUND_UP(abs(min_uV - old_uV), ramp_delay);
	usleep_range(ramp_delay, ramp_delay + DIV_ROUND_UP(ramp_delay, 10));

	return 0;
}

static struct regulator_ops pwm_regulator_voltage_table_ops = {
	.set_voltage_sel = pwm_regulator_set_voltage_sel,
	.get_voltage_sel = pwm_regulator_get_voltage_sel,
	.list_voltage    = pwm_regulator_list_voltage,
	.map_voltage     = regulator_map_voltage_iterate,
	.enable          = pwm_regulator_enable,
	.disable         = pwm_regulator_disable,
	.is_enabled      = pwm_regulator_is_enabled,
};

static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
	.get_voltage = pwm_regulator_get_voltage,
	.set_voltage = pwm_regulator_set_voltage,
	.enable          = pwm_regulator_enable,
	.disable         = pwm_regulator_disable,
	.is_enabled      = pwm_regulator_is_enabled,
};

static struct regulator_desc pwm_regulator_desc = {
	.name		= "pwm-regulator",
	.type		= REGULATOR_VOLTAGE,
	.owner		= THIS_MODULE,
	.supply_name    = "pwm",
};

static int pwm_regulator_init_table(struct platform_device *pdev,
				    struct pwm_regulator_data *drvdata)
{
	struct device_node *np = pdev->dev.of_node;
	struct pwm_voltages *duty_cycle_table;
	unsigned int length = 0;
	int ret;

	of_find_property(np, "voltage-table", &length);

	if ((length < sizeof(*duty_cycle_table)) ||
	    (length % sizeof(*duty_cycle_table))) {
		dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
			length);
		return -EINVAL;
	}

	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
	if (!duty_cycle_table)
		return -ENOMEM;

	ret = of_property_read_u32_array(np, "voltage-table",
					 (u32 *)duty_cycle_table,
					 length / sizeof(u32));
	if (ret) {
		dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
		return ret;
	}

	drvdata->duty_cycle_table	= duty_cycle_table;
	memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
	       sizeof(drvdata->ops));
	drvdata->desc.ops = &drvdata->ops;
	drvdata->desc.n_voltages	= length / sizeof(*duty_cycle_table);

	return 0;
}

static int pwm_regulator_init_continuous(struct platform_device *pdev,
					 struct pwm_regulator_data *drvdata)
{
	memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
	       sizeof(drvdata->ops));
	drvdata->desc.ops = &drvdata->ops;
	drvdata->desc.continuous_voltage_range = true;

	return 0;
}

static int pwm_regulator_probe(struct platform_device *pdev)
{
	const struct regulator_init_data *init_data;
	struct pwm_regulator_data *drvdata;
	struct regulator_dev *regulator;
	struct regulator_config config = { };
	struct device_node *np = pdev->dev.of_node;
	enum gpiod_flags gpio_flags;
	int ret;

	if (!np) {
		dev_err(&pdev->dev, "Device Tree node missing\n");
		return -EINVAL;
	}

	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
	if (!drvdata)
		return -ENOMEM;

	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));

	if (of_find_property(np, "voltage-table", NULL))
		ret = pwm_regulator_init_table(pdev, drvdata);
	else
		ret = pwm_regulator_init_continuous(pdev, drvdata);
	if (ret)
		return ret;

	init_data = of_get_regulator_init_data(&pdev->dev, np,
					       &drvdata->desc);
	if (!init_data)
		return -ENOMEM;

	config.of_node = np;
	config.dev = &pdev->dev;
	config.driver_data = drvdata;
	config.init_data = init_data;

	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
	if (IS_ERR(drvdata->pwm)) {
		ret = PTR_ERR(drvdata->pwm);
		dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
		return ret;
	}

	if (init_data->constraints.boot_on || init_data->constraints.always_on)
		gpio_flags = GPIOD_OUT_HIGH;
	else
		gpio_flags = GPIOD_OUT_LOW;
	drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
						    gpio_flags);
	if (IS_ERR(drvdata->enb_gpio)) {
		ret = PTR_ERR(drvdata->enb_gpio);
		dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
		return ret;
	}

	/*
	 * FIXME: pwm_apply_args() should be removed when switching to the
	 * atomic PWM API.
	 */
	pwm_apply_args(drvdata->pwm);

	regulator = devm_regulator_register(&pdev->dev,
					    &drvdata->desc, &config);
	if (IS_ERR(regulator)) {
		ret = PTR_ERR(regulator);
		dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
			drvdata->desc.name, ret);
		return ret;
	}

	return 0;
}

static const struct of_device_id pwm_of_match[] = {
	{ .compatible = "pwm-regulator" },
	{ },
};
MODULE_DEVICE_TABLE(of, pwm_of_match);

static struct platform_driver pwm_regulator_driver = {
	.driver = {
		.name		= "pwm-regulator",
		.of_match_table = of_match_ptr(pwm_of_match),
	},
	.probe = pwm_regulator_probe,
};

module_platform_driver(pwm_regulator_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
MODULE_DESCRIPTION("PWM Regulator Driver");
MODULE_ALIAS("platform:pwm-regulator");
Commit	Line	Data
aa66cc66 CZ	1	/*
	2	* Regulator driver for PWM Regulators
	3	*
	4	* Copyright (C) 2014 - STMicroelectronics Inc.
	5	*
	6	* Author: Lee Jones <lee.jones@linaro.org>
	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
4773be18	13	#include <linux/delay.h>
aa66cc66 CZ	14	#include <linux/module.h>
	15	#include <linux/init.h>
	16	#include <linux/err.h>
	17	#include <linux/regulator/driver.h>
	18	#include <linux/regulator/machine.h>
	19	#include <linux/regulator/of_regulator.h>
	20	#include <linux/of.h>
	21	#include <linux/of_device.h>
	22	#include <linux/pwm.h>
27bfa889	23	#include <linux/gpio/consumer.h>
aa66cc66 CZ	24
aa66cc66 CZ	25	struct pwm_regulator_data {
4773be18	26	/* Shared */
aa66cc66	27	struct pwm_device *pwm;
4773be18 LJ	28
	29	/* Voltage table */
	30	struct pwm_voltages *duty_cycle_table;
f907a0a9 LD	31
	32	/* regulator descriptor */
	33	struct regulator_desc desc;
	34
	35	/* Regulator ops */
	36	struct regulator_ops ops;
	37
aa66cc66	38	int state;
4773be18 LJ	39
4773be18 LJ	40	/* Continuous voltage */
4773be18	41	int volt_uV;
27bfa889 AC	42
	43	/* Enable GPIO */
	44	struct gpio_desc *enb_gpio;
aa66cc66 CZ	45	};
	46
	47	struct pwm_voltages {
	48	unsigned int uV;
	49	unsigned int dutycycle;
	50	};
	51
4773be18 LJ	52	/**
	53	* Voltage table call-backs
	54	*/
ab101e35	55	static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
aa66cc66	56	{
ab101e35	57	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66 CZ	58
	59	return drvdata->state;
	60	}
	61
ab101e35	62	static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
aa66cc66 CZ	63	unsigned selector)
aa66cc66 CZ	64	{
ab101e35	65	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
8c12ad8e	66	struct pwm_args pargs;
aa66cc66 CZ	67	int dutycycle;
	68	int ret;
	69
8c12ad8e	70	pwm_get_args(drvdata->pwm, &pargs);
aa66cc66	71
8c12ad8e	72	dutycycle = (pargs.period *
aa66cc66 CZ	73	drvdata->duty_cycle_table[selector].dutycycle) / 100;
aa66cc66 CZ	74
8c12ad8e	75	ret = pwm_config(drvdata->pwm, dutycycle, pargs.period);
aa66cc66	76	if (ret) {
5bf59bd5	77	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
aa66cc66 CZ	78	return ret;
	79	}
	80
	81	drvdata->state = selector;
	82
aa66cc66 CZ	83	return 0;
	84	}
	85
ab101e35	86	static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
aa66cc66 CZ	87	unsigned selector)
aa66cc66 CZ	88	{
ab101e35	89	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66	90
ab101e35	91	if (selector >= rdev->desc->n_voltages)
aa66cc66 CZ	92	return -EINVAL;
	93
	94	return drvdata->duty_cycle_table[selector].uV;
	95	}
4773be18	96
1de7d802 BB	97	static int pwm_regulator_enable(struct regulator_dev *dev)
	98	{
	99	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	100
27bfa889 AC	101	if (drvdata->enb_gpio)
	102	gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
	103
1de7d802 BB	104	return pwm_enable(drvdata->pwm);
	105	}
	106
	107	static int pwm_regulator_disable(struct regulator_dev *dev)
	108	{
	109	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	110
	111	pwm_disable(drvdata->pwm);
	112
27bfa889 AC	113	if (drvdata->enb_gpio)
	114	gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
	115
1de7d802 BB	116	return 0;
	117	}
	118
	119	static int pwm_regulator_is_enabled(struct regulator_dev *dev)
	120	{
	121	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	122
27bfa889 AC	123	if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
	124	return false;
	125
1de7d802 BB	126	return pwm_is_enabled(drvdata->pwm);
	127	}
	128
4773be18 LJ	129	static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
	130	{
	131	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	132
	133	return drvdata->volt_uV;
	134	}
	135
	136	static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
	137	int min_uV, int max_uV,
	138	unsigned *selector)
	139	{
	140	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	141	unsigned int ramp_delay = rdev->constraints->ramp_delay;
8c12ad8e	142	struct pwm_args pargs;
fd786fb0 LD	143	unsigned int req_diff = min_uV - rdev->constraints->min_uV;
	144	unsigned int diff;
	145	unsigned int duty_pulse;
	146	u64 req_period;
	147	u32 rem;
c2588393	148	int old_uV = pwm_regulator_get_voltage(rdev);
4773be18 LJ	149	int ret;
4773be18 LJ	150
8c12ad8e	151	pwm_get_args(drvdata->pwm, &pargs);
fd786fb0 LD	152	diff = rdev->constraints->max_uV - rdev->constraints->min_uV;
	153
	154	/* First try to find out if we get the iduty cycle time which is
	155	* factor of PWM period time. If (request_diff_to_min * pwm_period)
	156	* is perfect divided by voltage_range_diff then it is possible to
	157	* get duty cycle time which is factor of PWM period. This will help
	158	* to get output voltage nearer to requested value as there is no
	159	* calculation loss.
	160	*/
bc0868c6	161	req_period = req_diff * pargs.period;
fd786fb0 LD	162	div_u64_rem(req_period, diff, &rem);
	163	if (!rem) {
	164	do_div(req_period, diff);
	165	duty_pulse = (unsigned int)req_period;
	166	} else {
bc0868c6	167	duty_pulse = (pargs.period / 100) * ((req_diff * 100) / diff);
fd786fb0	168	}
4773be18	169
bc0868c6	170	ret = pwm_config(drvdata->pwm, duty_pulse, pargs.period);
4773be18	171	if (ret) {
5bf59bd5	172	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
4773be18 LJ	173	return ret;
	174	}
	175
4773be18 LJ	176	drvdata->volt_uV = min_uV;
4773be18 LJ	177
c2588393 DA	178	if ((ramp_delay == 0) \|\| !pwm_regulator_is_enabled(rdev))
	179	return 0;
	180
	181	/* Ramp delay is in uV/uS. Adjust to uS and delay */
	182	ramp_delay = DIV_ROUND_UP(abs(min_uV - old_uV), ramp_delay);
	183	usleep_range(ramp_delay, ramp_delay + DIV_ROUND_UP(ramp_delay, 10));
4773be18 LJ	184
	185	return 0;
	186	}
	187
f9178dad	188	static struct regulator_ops pwm_regulator_voltage_table_ops = {
aa66cc66 CZ	189	.set_voltage_sel = pwm_regulator_set_voltage_sel,
	190	.get_voltage_sel = pwm_regulator_get_voltage_sel,
	191	.list_voltage = pwm_regulator_list_voltage,
	192	.map_voltage = regulator_map_voltage_iterate,
1de7d802 BB	193	.enable = pwm_regulator_enable,
	194	.disable = pwm_regulator_disable,
	195	.is_enabled = pwm_regulator_is_enabled,
aa66cc66 CZ	196	};
aa66cc66 CZ	197
4773be18 LJ	198	static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
	199	.get_voltage = pwm_regulator_get_voltage,
	200	.set_voltage = pwm_regulator_set_voltage,
1de7d802 BB	201	.enable = pwm_regulator_enable,
	202	.disable = pwm_regulator_disable,
	203	.is_enabled = pwm_regulator_is_enabled,
4773be18 LJ	204	};
4773be18 LJ	205
b6f55e74	206	static struct regulator_desc pwm_regulator_desc = {
aa66cc66	207	.name = "pwm-regulator",
aa66cc66 CZ	208	.type = REGULATOR_VOLTAGE,
	209	.owner = THIS_MODULE,
	210	.supply_name = "pwm",
	211	};
	212
f9178dad LJ	213	static int pwm_regulator_init_table(struct platform_device *pdev,
	214	struct pwm_regulator_data *drvdata)
	215	{
	216	struct device_node *np = pdev->dev.of_node;
	217	struct pwm_voltages *duty_cycle_table;
60cb65eb	218	unsigned int length = 0;
f9178dad LJ	219	int ret;
	220
	221	of_find_property(np, "voltage-table", &length);
	222
	223	if ((length < sizeof(*duty_cycle_table)) \|\|
	224	(length % sizeof(*duty_cycle_table))) {
5bf59bd5	225	dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
f9178dad LJ	226	length);
	227	return -EINVAL;
	228	}
	229
	230	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
	231	if (!duty_cycle_table)
	232	return -ENOMEM;
	233
	234	ret = of_property_read_u32_array(np, "voltage-table",
	235	(u32 *)duty_cycle_table,
	236	length / sizeof(u32));
	237	if (ret) {
5bf59bd5	238	dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
f9178dad LJ	239	return ret;
	240	}
	241
	242	drvdata->duty_cycle_table = duty_cycle_table;
f907a0a9 LD	243	memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
	244	sizeof(drvdata->ops));
	245	drvdata->desc.ops = &drvdata->ops;
	246	drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table);
f9178dad LJ	247
	248	return 0;
	249	}
	250
4773be18 LJ	251	static int pwm_regulator_init_continuous(struct platform_device *pdev,
	252	struct pwm_regulator_data *drvdata)
	253	{
f907a0a9 LD	254	memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
	255	sizeof(drvdata->ops));
	256	drvdata->desc.ops = &drvdata->ops;
	257	drvdata->desc.continuous_voltage_range = true;
4773be18 LJ	258
	259	return 0;
	260	}
	261
aa66cc66 CZ	262	static int pwm_regulator_probe(struct platform_device *pdev)
aa66cc66 CZ	263	{
5ad2cb14	264	const struct regulator_init_data *init_data;
aa66cc66	265	struct pwm_regulator_data *drvdata;
aa66cc66 CZ	266	struct regulator_dev *regulator;
	267	struct regulator_config config = { };
	268	struct device_node *np = pdev->dev.of_node;
27bfa889	269	enum gpiod_flags gpio_flags;
f9178dad	270	int ret;
aa66cc66 CZ	271
	272	if (!np) {
	273	dev_err(&pdev->dev, "Device Tree node missing\n");
	274	return -EINVAL;
	275	}
	276
	277	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
	278	if (!drvdata)
	279	return -ENOMEM;
	280
f907a0a9 LD	281	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
f907a0a9 LD	282
4773be18	283	if (of_find_property(np, "voltage-table", NULL))
f9178dad	284	ret = pwm_regulator_init_table(pdev, drvdata);
4773be18 LJ	285	else
	286	ret = pwm_regulator_init_continuous(pdev, drvdata);
	287	if (ret)
	288	return ret;
aa66cc66	289
5ad2cb14	290	init_data = of_get_regulator_init_data(&pdev->dev, np,
f907a0a9	291	&drvdata->desc);
5ad2cb14	292	if (!init_data)
aa66cc66 CZ	293	return -ENOMEM;
	294
	295	config.of_node = np;
	296	config.dev = &pdev->dev;
	297	config.driver_data = drvdata;
5ad2cb14	298	config.init_data = init_data;
aa66cc66 CZ	299
	300	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
	301	if (IS_ERR(drvdata->pwm)) {
5bf59bd5 LD	302	ret = PTR_ERR(drvdata->pwm);
	303	dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
	304	return ret;
aa66cc66 CZ	305	}
aa66cc66 CZ	306
27bfa889 AC	307	if (init_data->constraints.boot_on \|\| init_data->constraints.always_on)
	308	gpio_flags = GPIOD_OUT_HIGH;
	309	else
	310	gpio_flags = GPIOD_OUT_LOW;
	311	drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
	312	gpio_flags);
	313	if (IS_ERR(drvdata->enb_gpio)) {
	314	ret = PTR_ERR(drvdata->enb_gpio);
	315	dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
	316	return ret;
	317	}
	318
8c12ad8e BB	319	/*
	320	* FIXME: pwm_apply_args() should be removed when switching to the
	321	* atomic PWM API.
	322	*/
	323	pwm_apply_args(drvdata->pwm);
	324
aa66cc66	325	regulator = devm_regulator_register(&pdev->dev,
f907a0a9	326	&drvdata->desc, &config);
aa66cc66	327	if (IS_ERR(regulator)) {
5bf59bd5 LD	328	ret = PTR_ERR(regulator);
	329	dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
	330	drvdata->desc.name, ret);
	331	return ret;
aa66cc66 CZ	332	}
	333
	334	return 0;
	335	}
	336
	337	static const struct of_device_id pwm_of_match[] = {
	338	{ .compatible = "pwm-regulator" },
	339	{ },
	340	};
	341	MODULE_DEVICE_TABLE(of, pwm_of_match);
	342
	343	static struct platform_driver pwm_regulator_driver = {
	344	.driver = {
	345	.name = "pwm-regulator",
aa66cc66 CZ	346	.of_match_table = of_match_ptr(pwm_of_match),
	347	},
	348	.probe = pwm_regulator_probe,
	349	};
	350
	351	module_platform_driver(pwm_regulator_driver);
	352
	353	MODULE_LICENSE("GPL");
	354	MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
	355	MODULE_DESCRIPTION("PWM Regulator Driver");
	356	MODULE_ALIAS("platform:pwm-regulator");