[mirror_ubuntu-zesty-kernel.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/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_continuous_reg_data {
	unsigned int min_uV_dutycycle;
	unsigned int max_uV_dutycycle;
	unsigned int dutycycle_unit;
};

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

	/* Voltage table */
	struct pwm_voltages *duty_cycle_table;

	/* Continuous mode info */
	struct pwm_continuous_reg_data continuous;

	/* regulator descriptor */
	struct regulator_desc desc;

	/* Regulator ops */
	struct regulator_ops ops;

	int state;

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

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

/**
 * Voltage table call-backs
 */
static void pwm_regulator_init_state(struct regulator_dev *rdev)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	struct pwm_state pwm_state;
	unsigned int dutycycle;
	int i;

	pwm_get_state(drvdata->pwm, &pwm_state);
	dutycycle = pwm_get_relative_duty_cycle(&pwm_state, 100);

	for (i = 0; i < rdev->desc->n_voltages; i++) {
		if (dutycycle == drvdata->duty_cycle_table[i].dutycycle) {
			drvdata->state = i;
			return;
		}
	}
}

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

	if (drvdata->state < 0)
		pwm_regulator_init_state(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_state pstate;
	int ret;

	pwm_init_state(drvdata->pwm, &pstate);
	pwm_set_relative_duty_cycle(&pstate,
			drvdata->duty_cycle_table[selector].dutycycle, 100);

	ret = pwm_apply_state(drvdata->pwm, &pstate);
	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);
	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
	int min_uV = rdev->constraints->min_uV;
	int max_uV = rdev->constraints->max_uV;
	int diff_uV = max_uV - min_uV;
	struct pwm_state pstate;
	unsigned int diff_duty;
	unsigned int voltage;

	pwm_get_state(drvdata->pwm, &pstate);

	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);

	/*
	 * The dutycycle for min_uV might be greater than the one for max_uV.
	 * This is happening when the user needs an inversed polarity, but the
	 * PWM device does not support inversing it in hardware.
	 */
	if (max_uV_duty < min_uV_duty) {
		voltage = min_uV_duty - voltage;
		diff_duty = min_uV_duty - max_uV_duty;
	} else {
		voltage = voltage - min_uV_duty;
		diff_duty = max_uV_duty - min_uV_duty;
	}

	voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);

	return voltage + min_uV;
}

static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
				     int req_min_uV, int req_max_uV,
				     unsigned int *selector)
{
	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
	int min_uV = rdev->constraints->min_uV;
	int max_uV = rdev->constraints->max_uV;
	int diff_uV = max_uV - min_uV;
	struct pwm_state pstate;
	unsigned int diff_duty;
	unsigned int dutycycle;
	int ret;

	pwm_init_state(drvdata->pwm, &pstate);

	/*
	 * The dutycycle for min_uV might be greater than the one for max_uV.
	 * This is happening when the user needs an inversed polarity, but the
	 * PWM device does not support inversing it in hardware.
	 */
	if (max_uV_duty < min_uV_duty)
		diff_duty = min_uV_duty - max_uV_duty;
	else
		diff_duty = max_uV_duty - min_uV_duty;

	dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
					  diff_duty,
					  diff_uV);

	if (max_uV_duty < min_uV_duty)
		dutycycle = min_uV_duty - dutycycle;
	else
		dutycycle = min_uV_duty + dutycycle;

	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);

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

	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->state			= -EINVAL;
	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)
{
	u32 dutycycle_range[2] = { 0, 100 };
	u32 dutycycle_unit = 100;

	memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
	       sizeof(drvdata->ops));
	drvdata->desc.ops = &drvdata->ops;
	drvdata->desc.continuous_voltage_range = true;

	of_property_read_u32_array(pdev->dev.of_node,
				   "pwm-dutycycle-range",
				   dutycycle_range, 2);
	of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
			     &dutycycle_unit);

	if (dutycycle_range[0] > dutycycle_unit ||
	    dutycycle_range[1] > dutycycle_unit)
		return -EINVAL;

	drvdata->continuous.dutycycle_unit = dutycycle_unit;
	drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
	drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];

	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;
	}

	ret = pwm_adjust_config(drvdata->pwm);
	if (ret)
		return ret;

	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
	13	#include <linux/module.h>
	14	#include <linux/init.h>
	15	#include <linux/err.h>
	16	#include <linux/regulator/driver.h>
	17	#include <linux/regulator/machine.h>
	18	#include <linux/regulator/of_regulator.h>
	19	#include <linux/of.h>
	20	#include <linux/of_device.h>
	21	#include <linux/pwm.h>
27bfa889	22	#include <linux/gpio/consumer.h>
aa66cc66	23
ea398e28 BB	24	struct pwm_continuous_reg_data {
	25	unsigned int min_uV_dutycycle;
	26	unsigned int max_uV_dutycycle;
	27	unsigned int dutycycle_unit;
	28	};
	29
aa66cc66	30	struct pwm_regulator_data {
4773be18	31	/* Shared */
aa66cc66	32	struct pwm_device *pwm;
4773be18 LJ	33
	34	/* Voltage table */
	35	struct pwm_voltages *duty_cycle_table;
f907a0a9	36
ea398e28 BB	37	/* Continuous mode info */
	38	struct pwm_continuous_reg_data continuous;
	39
f907a0a9 LD	40	/* regulator descriptor */
	41	struct regulator_desc desc;
	42
	43	/* Regulator ops */
	44	struct regulator_ops ops;
	45
aa66cc66	46	int state;
4773be18	47
27bfa889 AC	48	/* Enable GPIO */
27bfa889 AC	49	struct gpio_desc *enb_gpio;
aa66cc66 CZ	50	};
	51
	52	struct pwm_voltages {
	53	unsigned int uV;
	54	unsigned int dutycycle;
	55	};
	56
4773be18 LJ	57	/**
	58	* Voltage table call-backs
	59	*/
87248991 BB	60	static void pwm_regulator_init_state(struct regulator_dev *rdev)
	61	{
	62	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	63	struct pwm_state pwm_state;
	64	unsigned int dutycycle;
	65	int i;
	66
	67	pwm_get_state(drvdata->pwm, &pwm_state);
	68	dutycycle = pwm_get_relative_duty_cycle(&pwm_state, 100);
	69
	70	for (i = 0; i < rdev->desc->n_voltages; i++) {
	71	if (dutycycle == drvdata->duty_cycle_table[i].dutycycle) {
	72	drvdata->state = i;
	73	return;
	74	}
	75	}
	76	}
	77
ab101e35	78	static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
aa66cc66	79	{
ab101e35	80	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66	81
87248991 BB	82	if (drvdata->state < 0)
	83	pwm_regulator_init_state(rdev);
	84
aa66cc66 CZ	85	return drvdata->state;
	86	}
	87
ab101e35	88	static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
aa66cc66 CZ	89	unsigned selector)
aa66cc66 CZ	90	{
ab101e35	91	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
3f4eb39b	92	struct pwm_state pstate;
aa66cc66 CZ	93	int ret;
aa66cc66 CZ	94
3f4eb39b BB	95	pwm_init_state(drvdata->pwm, &pstate);
	96	pwm_set_relative_duty_cycle(&pstate,
	97	drvdata->duty_cycle_table[selector].dutycycle, 100);
aa66cc66	98
3f4eb39b	99	ret = pwm_apply_state(drvdata->pwm, &pstate);
aa66cc66	100	if (ret) {
5bf59bd5	101	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
aa66cc66 CZ	102	return ret;
	103	}
	104
	105	drvdata->state = selector;
	106
aa66cc66 CZ	107	return 0;
	108	}
	109
ab101e35	110	static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
aa66cc66 CZ	111	unsigned selector)
aa66cc66 CZ	112	{
ab101e35	113	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66	114
ab101e35	115	if (selector >= rdev->desc->n_voltages)
aa66cc66 CZ	116	return -EINVAL;
	117
	118	return drvdata->duty_cycle_table[selector].uV;
	119	}
4773be18	120
1de7d802 BB	121	static int pwm_regulator_enable(struct regulator_dev *dev)
	122	{
	123	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	124
27bfa889 AC	125	if (drvdata->enb_gpio)
	126	gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
	127
1de7d802 BB	128	return pwm_enable(drvdata->pwm);
	129	}
	130
	131	static int pwm_regulator_disable(struct regulator_dev *dev)
	132	{
	133	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	134
	135	pwm_disable(drvdata->pwm);
	136
27bfa889 AC	137	if (drvdata->enb_gpio)
	138	gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
	139
1de7d802 BB	140	return 0;
	141	}
	142
	143	static int pwm_regulator_is_enabled(struct regulator_dev *dev)
	144	{
	145	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	146
27bfa889 AC	147	if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
	148	return false;
	149
1de7d802 BB	150	return pwm_is_enabled(drvdata->pwm);
	151	}
	152
4773be18 LJ	153	static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
	154	{
	155	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	156	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	157	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	158	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
d9070fdb	159	int min_uV = rdev->constraints->min_uV;
ea398e28 BB	160	int max_uV = rdev->constraints->max_uV;
ea398e28 BB	161	int diff_uV = max_uV - min_uV;
d9070fdb	162	struct pwm_state pstate;
ea398e28 BB	163	unsigned int diff_duty;
ea398e28 BB	164	unsigned int voltage;
4773be18	165
d9070fdb BB	166	pwm_get_state(drvdata->pwm, &pstate);
d9070fdb BB	167
ea398e28 BB	168	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
	169
	170	/*
	171	* The dutycycle for min_uV might be greater than the one for max_uV.
	172	* This is happening when the user needs an inversed polarity, but the
	173	* PWM device does not support inversing it in hardware.
	174	*/
	175	if (max_uV_duty < min_uV_duty) {
	176	voltage = min_uV_duty - voltage;
	177	diff_duty = min_uV_duty - max_uV_duty;
	178	} else {
	179	voltage = voltage - min_uV_duty;
	180	diff_duty = max_uV_duty - min_uV_duty;
	181	}
	182
	183	voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);
	184
	185	return voltage + min_uV;
4773be18 LJ	186	}
	187
	188	static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
ea398e28 BB	189	int req_min_uV, int req_max_uV,
ea398e28 BB	190	unsigned int *selector)
4773be18 LJ	191	{
4773be18 LJ	192	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	193	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	194	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	195	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
ea398e28 BB	196	int min_uV = rdev->constraints->min_uV;
	197	int max_uV = rdev->constraints->max_uV;
	198	int diff_uV = max_uV - min_uV;
3f4eb39b	199	struct pwm_state pstate;
ea398e28 BB	200	unsigned int diff_duty;
ea398e28 BB	201	unsigned int dutycycle;
4773be18 LJ	202	int ret;
4773be18 LJ	203
3f4eb39b	204	pwm_init_state(drvdata->pwm, &pstate);
fd786fb0	205
ea398e28 BB	206	/*
	207	* The dutycycle for min_uV might be greater than the one for max_uV.
	208	* This is happening when the user needs an inversed polarity, but the
	209	* PWM device does not support inversing it in hardware.
	210	*/
	211	if (max_uV_duty < min_uV_duty)
	212	diff_duty = min_uV_duty - max_uV_duty;
	213	else
	214	diff_duty = max_uV_duty - min_uV_duty;
	215
	216	dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
	217	diff_duty,
	218	diff_uV);
	219
	220	if (max_uV_duty < min_uV_duty)
	221	dutycycle = min_uV_duty - dutycycle;
	222	else
	223	dutycycle = min_uV_duty + dutycycle;
	224
	225	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
4773be18	226
3f4eb39b	227	ret = pwm_apply_state(drvdata->pwm, &pstate);
4773be18	228	if (ret) {
5bf59bd5	229	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
4773be18 LJ	230	return ret;
	231	}
	232
4773be18 LJ	233	return 0;
	234	}
	235
f9178dad	236	static struct regulator_ops pwm_regulator_voltage_table_ops = {
aa66cc66 CZ	237	.set_voltage_sel = pwm_regulator_set_voltage_sel,
	238	.get_voltage_sel = pwm_regulator_get_voltage_sel,
	239	.list_voltage = pwm_regulator_list_voltage,
	240	.map_voltage = regulator_map_voltage_iterate,
1de7d802 BB	241	.enable = pwm_regulator_enable,
	242	.disable = pwm_regulator_disable,
	243	.is_enabled = pwm_regulator_is_enabled,
aa66cc66 CZ	244	};
aa66cc66 CZ	245
4773be18 LJ	246	static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
	247	.get_voltage = pwm_regulator_get_voltage,
	248	.set_voltage = pwm_regulator_set_voltage,
1de7d802 BB	249	.enable = pwm_regulator_enable,
	250	.disable = pwm_regulator_disable,
	251	.is_enabled = pwm_regulator_is_enabled,
4773be18 LJ	252	};
4773be18 LJ	253
b6f55e74	254	static struct regulator_desc pwm_regulator_desc = {
aa66cc66	255	.name = "pwm-regulator",
aa66cc66 CZ	256	.type = REGULATOR_VOLTAGE,
	257	.owner = THIS_MODULE,
	258	.supply_name = "pwm",
	259	};
	260
f9178dad LJ	261	static int pwm_regulator_init_table(struct platform_device *pdev,
	262	struct pwm_regulator_data *drvdata)
	263	{
	264	struct device_node *np = pdev->dev.of_node;
	265	struct pwm_voltages *duty_cycle_table;
60cb65eb	266	unsigned int length = 0;
f9178dad LJ	267	int ret;
	268
	269	of_find_property(np, "voltage-table", &length);
	270
	271	if ((length < sizeof(*duty_cycle_table)) \|\|
	272	(length % sizeof(*duty_cycle_table))) {
5bf59bd5	273	dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
f9178dad LJ	274	length);
	275	return -EINVAL;
	276	}
	277
	278	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
	279	if (!duty_cycle_table)
	280	return -ENOMEM;
	281
	282	ret = of_property_read_u32_array(np, "voltage-table",
	283	(u32 *)duty_cycle_table,
	284	length / sizeof(u32));
	285	if (ret) {
5bf59bd5	286	dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
f9178dad LJ	287	return ret;
	288	}
	289
87248991	290	drvdata->state = -EINVAL;
f9178dad	291	drvdata->duty_cycle_table = duty_cycle_table;
f907a0a9 LD	292	memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
	293	sizeof(drvdata->ops));
	294	drvdata->desc.ops = &drvdata->ops;
	295	drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table);
f9178dad LJ	296
	297	return 0;
	298	}
	299
4773be18 LJ	300	static int pwm_regulator_init_continuous(struct platform_device *pdev,
	301	struct pwm_regulator_data *drvdata)
	302	{
ea398e28 BB	303	u32 dutycycle_range[2] = { 0, 100 };
	304	u32 dutycycle_unit = 100;
	305
f907a0a9 LD	306	memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
	307	sizeof(drvdata->ops));
	308	drvdata->desc.ops = &drvdata->ops;
	309	drvdata->desc.continuous_voltage_range = true;
4773be18	310
ea398e28 BB	311	of_property_read_u32_array(pdev->dev.of_node,
	312	"pwm-dutycycle-range",
	313	dutycycle_range, 2);
	314	of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
	315	&dutycycle_unit);
	316
	317	if (dutycycle_range[0] > dutycycle_unit \|\|
	318	dutycycle_range[1] > dutycycle_unit)
	319	return -EINVAL;
	320
	321	drvdata->continuous.dutycycle_unit = dutycycle_unit;
	322	drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
	323	drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];
	324
4773be18 LJ	325	return 0;
	326	}
	327
aa66cc66 CZ	328	static int pwm_regulator_probe(struct platform_device *pdev)
aa66cc66 CZ	329	{
5ad2cb14	330	const struct regulator_init_data *init_data;
aa66cc66	331	struct pwm_regulator_data *drvdata;
aa66cc66 CZ	332	struct regulator_dev *regulator;
	333	struct regulator_config config = { };
	334	struct device_node *np = pdev->dev.of_node;
27bfa889	335	enum gpiod_flags gpio_flags;
f9178dad	336	int ret;
aa66cc66 CZ	337
	338	if (!np) {
	339	dev_err(&pdev->dev, "Device Tree node missing\n");
	340	return -EINVAL;
	341	}
	342
	343	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
	344	if (!drvdata)
	345	return -ENOMEM;
	346
f907a0a9 LD	347	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
f907a0a9 LD	348
4773be18	349	if (of_find_property(np, "voltage-table", NULL))
f9178dad	350	ret = pwm_regulator_init_table(pdev, drvdata);
4773be18 LJ	351	else
	352	ret = pwm_regulator_init_continuous(pdev, drvdata);
	353	if (ret)
	354	return ret;
aa66cc66	355
5ad2cb14	356	init_data = of_get_regulator_init_data(&pdev->dev, np,
f907a0a9	357	&drvdata->desc);
5ad2cb14	358	if (!init_data)
aa66cc66 CZ	359	return -ENOMEM;
	360
	361	config.of_node = np;
	362	config.dev = &pdev->dev;
	363	config.driver_data = drvdata;
5ad2cb14	364	config.init_data = init_data;
aa66cc66 CZ	365
	366	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
	367	if (IS_ERR(drvdata->pwm)) {
5bf59bd5 LD	368	ret = PTR_ERR(drvdata->pwm);
	369	dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
	370	return ret;
aa66cc66 CZ	371	}
aa66cc66 CZ	372
27bfa889 AC	373	if (init_data->constraints.boot_on \|\| init_data->constraints.always_on)
	374	gpio_flags = GPIOD_OUT_HIGH;
	375	else
	376	gpio_flags = GPIOD_OUT_LOW;
	377	drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
	378	gpio_flags);
	379	if (IS_ERR(drvdata->enb_gpio)) {
	380	ret = PTR_ERR(drvdata->enb_gpio);
	381	dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
	382	return ret;
	383	}
	384
fd4f99c4 BB	385	ret = pwm_adjust_config(drvdata->pwm);
	386	if (ret)
	387	return ret;
8c12ad8e	388
aa66cc66	389	regulator = devm_regulator_register(&pdev->dev,
f907a0a9	390	&drvdata->desc, &config);
aa66cc66	391	if (IS_ERR(regulator)) {
5bf59bd5 LD	392	ret = PTR_ERR(regulator);
	393	dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
	394	drvdata->desc.name, ret);
	395	return ret;
aa66cc66 CZ	396	}
	397
	398	return 0;
	399	}
	400
	401	static const struct of_device_id pwm_of_match[] = {
	402	{ .compatible = "pwm-regulator" },
	403	{ },
	404	};
	405	MODULE_DEVICE_TABLE(of, pwm_of_match);
	406
	407	static struct platform_driver pwm_regulator_driver = {
	408	.driver = {
	409	.name = "pwm-regulator",
aa66cc66 CZ	410	.of_match_table = of_match_ptr(pwm_of_match),
	411	},
	412	.probe = pwm_regulator_probe,
	413	};
	414
	415	module_platform_driver(pwm_regulator_driver);
	416
	417	MODULE_LICENSE("GPL");
	418	MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
	419	MODULE_DESCRIPTION("PWM Regulator Driver");
	420	MODULE_ALIAS("platform:pwm-regulator");