[mirror_ubuntu-jammy-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;

	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);

	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);

	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 const 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 const 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 const 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;
	drvdata->desc.ops = &pwm_regulator_voltage_table_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;

	drvdata->desc.ops = &pwm_regulator_voltage_continuous_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
aa66cc66	43	int state;
4773be18	44
27bfa889 AC	45	/* Enable GPIO */
27bfa889 AC	46	struct gpio_desc *enb_gpio;
aa66cc66 CZ	47	};
	48
	49	struct pwm_voltages {
	50	unsigned int uV;
	51	unsigned int dutycycle;
	52	};
	53
4773be18 LJ	54	/**
	55	* Voltage table call-backs
	56	*/
87248991 BB	57	static void pwm_regulator_init_state(struct regulator_dev *rdev)
	58	{
	59	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	60	struct pwm_state pwm_state;
	61	unsigned int dutycycle;
	62	int i;
	63
	64	pwm_get_state(drvdata->pwm, &pwm_state);
	65	dutycycle = pwm_get_relative_duty_cycle(&pwm_state, 100);
	66
	67	for (i = 0; i < rdev->desc->n_voltages; i++) {
	68	if (dutycycle == drvdata->duty_cycle_table[i].dutycycle) {
	69	drvdata->state = i;
	70	return;
	71	}
	72	}
	73	}
	74
ab101e35	75	static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
aa66cc66	76	{
ab101e35	77	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66	78
87248991 BB	79	if (drvdata->state < 0)
	80	pwm_regulator_init_state(rdev);
	81
aa66cc66 CZ	82	return drvdata->state;
	83	}
	84
ab101e35	85	static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
aa66cc66 CZ	86	unsigned selector)
aa66cc66 CZ	87	{
ab101e35	88	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
3f4eb39b	89	struct pwm_state pstate;
aa66cc66 CZ	90	int ret;
aa66cc66 CZ	91
3f4eb39b BB	92	pwm_init_state(drvdata->pwm, &pstate);
	93	pwm_set_relative_duty_cycle(&pstate,
	94	drvdata->duty_cycle_table[selector].dutycycle, 100);
aa66cc66	95
3f4eb39b	96	ret = pwm_apply_state(drvdata->pwm, &pstate);
aa66cc66	97	if (ret) {
5bf59bd5	98	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
aa66cc66 CZ	99	return ret;
	100	}
	101
	102	drvdata->state = selector;
	103
aa66cc66 CZ	104	return 0;
	105	}
	106
ab101e35	107	static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
aa66cc66 CZ	108	unsigned selector)
aa66cc66 CZ	109	{
ab101e35	110	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66	111
ab101e35	112	if (selector >= rdev->desc->n_voltages)
aa66cc66 CZ	113	return -EINVAL;
	114
	115	return drvdata->duty_cycle_table[selector].uV;
	116	}
4773be18	117
1de7d802 BB	118	static int pwm_regulator_enable(struct regulator_dev *dev)
	119	{
	120	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	121
a4aae5af	122	gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
27bfa889	123
1de7d802 BB	124	return pwm_enable(drvdata->pwm);
	125	}
	126
	127	static int pwm_regulator_disable(struct regulator_dev *dev)
	128	{
	129	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	130
	131	pwm_disable(drvdata->pwm);
	132
a4aae5af	133	gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
27bfa889	134
1de7d802 BB	135	return 0;
	136	}
	137
	138	static int pwm_regulator_is_enabled(struct regulator_dev *dev)
	139	{
	140	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	141
27bfa889 AC	142	if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
	143	return false;
	144
1de7d802 BB	145	return pwm_is_enabled(drvdata->pwm);
	146	}
	147
4773be18 LJ	148	static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
	149	{
	150	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	151	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	152	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	153	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
d9070fdb	154	int min_uV = rdev->constraints->min_uV;
ea398e28 BB	155	int max_uV = rdev->constraints->max_uV;
ea398e28 BB	156	int diff_uV = max_uV - min_uV;
d9070fdb	157	struct pwm_state pstate;
ea398e28 BB	158	unsigned int diff_duty;
ea398e28 BB	159	unsigned int voltage;
4773be18	160
d9070fdb BB	161	pwm_get_state(drvdata->pwm, &pstate);
d9070fdb BB	162
ea398e28 BB	163	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
	164
	165	/*
	166	* The dutycycle for min_uV might be greater than the one for max_uV.
	167	* This is happening when the user needs an inversed polarity, but the
	168	* PWM device does not support inversing it in hardware.
	169	*/
	170	if (max_uV_duty < min_uV_duty) {
	171	voltage = min_uV_duty - voltage;
	172	diff_duty = min_uV_duty - max_uV_duty;
	173	} else {
	174	voltage = voltage - min_uV_duty;
	175	diff_duty = max_uV_duty - min_uV_duty;
	176	}
	177
	178	voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);
	179
	180	return voltage + min_uV;
4773be18 LJ	181	}
	182
	183	static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
ea398e28 BB	184	int req_min_uV, int req_max_uV,
ea398e28 BB	185	unsigned int *selector)
4773be18 LJ	186	{
4773be18 LJ	187	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	188	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	189	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	190	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
ea398e28 BB	191	int min_uV = rdev->constraints->min_uV;
	192	int max_uV = rdev->constraints->max_uV;
	193	int diff_uV = max_uV - min_uV;
3f4eb39b	194	struct pwm_state pstate;
ea398e28 BB	195	unsigned int diff_duty;
ea398e28 BB	196	unsigned int dutycycle;
4773be18 LJ	197	int ret;
4773be18 LJ	198
3f4eb39b	199	pwm_init_state(drvdata->pwm, &pstate);
fd786fb0	200
ea398e28 BB	201	/*
	202	* The dutycycle for min_uV might be greater than the one for max_uV.
	203	* This is happening when the user needs an inversed polarity, but the
	204	* PWM device does not support inversing it in hardware.
	205	*/
	206	if (max_uV_duty < min_uV_duty)
	207	diff_duty = min_uV_duty - max_uV_duty;
	208	else
	209	diff_duty = max_uV_duty - min_uV_duty;
	210
	211	dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
	212	diff_duty,
	213	diff_uV);
	214
	215	if (max_uV_duty < min_uV_duty)
	216	dutycycle = min_uV_duty - dutycycle;
	217	else
	218	dutycycle = min_uV_duty + dutycycle;
	219
	220	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
4773be18	221
3f4eb39b	222	ret = pwm_apply_state(drvdata->pwm, &pstate);
4773be18	223	if (ret) {
5bf59bd5	224	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
4773be18 LJ	225	return ret;
	226	}
	227
4773be18 LJ	228	return 0;
	229	}
	230
638aef7a	231	static const struct regulator_ops pwm_regulator_voltage_table_ops = {
aa66cc66 CZ	232	.set_voltage_sel = pwm_regulator_set_voltage_sel,
	233	.get_voltage_sel = pwm_regulator_get_voltage_sel,
	234	.list_voltage = pwm_regulator_list_voltage,
	235	.map_voltage = regulator_map_voltage_iterate,
1de7d802 BB	236	.enable = pwm_regulator_enable,
	237	.disable = pwm_regulator_disable,
	238	.is_enabled = pwm_regulator_is_enabled,
aa66cc66 CZ	239	};
aa66cc66 CZ	240
638aef7a	241	static const struct regulator_ops pwm_regulator_voltage_continuous_ops = {
4773be18 LJ	242	.get_voltage = pwm_regulator_get_voltage,
4773be18 LJ	243	.set_voltage = pwm_regulator_set_voltage,
1de7d802 BB	244	.enable = pwm_regulator_enable,
	245	.disable = pwm_regulator_disable,
	246	.is_enabled = pwm_regulator_is_enabled,
4773be18 LJ	247	};
4773be18 LJ	248
638aef7a	249	static const struct regulator_desc pwm_regulator_desc = {
aa66cc66	250	.name = "pwm-regulator",
aa66cc66 CZ	251	.type = REGULATOR_VOLTAGE,
	252	.owner = THIS_MODULE,
	253	.supply_name = "pwm",
	254	};
	255
f9178dad LJ	256	static int pwm_regulator_init_table(struct platform_device *pdev,
	257	struct pwm_regulator_data *drvdata)
	258	{
	259	struct device_node *np = pdev->dev.of_node;
	260	struct pwm_voltages *duty_cycle_table;
60cb65eb	261	unsigned int length = 0;
f9178dad LJ	262	int ret;
	263
	264	of_find_property(np, "voltage-table", &length);
	265
	266	if ((length < sizeof(*duty_cycle_table)) \|\|
	267	(length % sizeof(*duty_cycle_table))) {
5bf59bd5	268	dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
f9178dad LJ	269	length);
	270	return -EINVAL;
	271	}
	272
	273	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
	274	if (!duty_cycle_table)
	275	return -ENOMEM;
	276
	277	ret = of_property_read_u32_array(np, "voltage-table",
	278	(u32 *)duty_cycle_table,
	279	length / sizeof(u32));
	280	if (ret) {
5bf59bd5	281	dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
f9178dad LJ	282	return ret;
	283	}
	284
87248991	285	drvdata->state = -EINVAL;
f9178dad	286	drvdata->duty_cycle_table = duty_cycle_table;
638aef7a	287	drvdata->desc.ops = &pwm_regulator_voltage_table_ops;
f907a0a9	288	drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table);
f9178dad LJ	289
	290	return 0;
	291	}
	292
4773be18 LJ	293	static int pwm_regulator_init_continuous(struct platform_device *pdev,
	294	struct pwm_regulator_data *drvdata)
	295	{
ea398e28 BB	296	u32 dutycycle_range[2] = { 0, 100 };
	297	u32 dutycycle_unit = 100;
	298
638aef7a	299	drvdata->desc.ops = &pwm_regulator_voltage_continuous_ops;
f907a0a9	300	drvdata->desc.continuous_voltage_range = true;
4773be18	301
ea398e28 BB	302	of_property_read_u32_array(pdev->dev.of_node,
	303	"pwm-dutycycle-range",
	304	dutycycle_range, 2);
	305	of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
	306	&dutycycle_unit);
	307
	308	if (dutycycle_range[0] > dutycycle_unit \|\|
	309	dutycycle_range[1] > dutycycle_unit)
	310	return -EINVAL;
	311
	312	drvdata->continuous.dutycycle_unit = dutycycle_unit;
	313	drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
	314	drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];
	315
4773be18 LJ	316	return 0;
	317	}
	318
aa66cc66 CZ	319	static int pwm_regulator_probe(struct platform_device *pdev)
aa66cc66 CZ	320	{
5ad2cb14	321	const struct regulator_init_data *init_data;
aa66cc66	322	struct pwm_regulator_data *drvdata;
aa66cc66 CZ	323	struct regulator_dev *regulator;
	324	struct regulator_config config = { };
	325	struct device_node *np = pdev->dev.of_node;
27bfa889	326	enum gpiod_flags gpio_flags;
f9178dad	327	int ret;
aa66cc66 CZ	328
	329	if (!np) {
	330	dev_err(&pdev->dev, "Device Tree node missing\n");
	331	return -EINVAL;
	332	}
	333
	334	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
	335	if (!drvdata)
	336	return -ENOMEM;
	337
f907a0a9 LD	338	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
f907a0a9 LD	339
4773be18	340	if (of_find_property(np, "voltage-table", NULL))
f9178dad	341	ret = pwm_regulator_init_table(pdev, drvdata);
4773be18 LJ	342	else
	343	ret = pwm_regulator_init_continuous(pdev, drvdata);
	344	if (ret)
	345	return ret;
aa66cc66	346
5ad2cb14	347	init_data = of_get_regulator_init_data(&pdev->dev, np,
f907a0a9	348	&drvdata->desc);
5ad2cb14	349	if (!init_data)
aa66cc66 CZ	350	return -ENOMEM;
	351
	352	config.of_node = np;
	353	config.dev = &pdev->dev;
	354	config.driver_data = drvdata;
5ad2cb14	355	config.init_data = init_data;
aa66cc66 CZ	356
	357	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
	358	if (IS_ERR(drvdata->pwm)) {
5bf59bd5 LD	359	ret = PTR_ERR(drvdata->pwm);
	360	dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
	361	return ret;
aa66cc66 CZ	362	}
aa66cc66 CZ	363
27bfa889 AC	364	if (init_data->constraints.boot_on \|\| init_data->constraints.always_on)
	365	gpio_flags = GPIOD_OUT_HIGH;
	366	else
	367	gpio_flags = GPIOD_OUT_LOW;
	368	drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
	369	gpio_flags);
	370	if (IS_ERR(drvdata->enb_gpio)) {
	371	ret = PTR_ERR(drvdata->enb_gpio);
	372	dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
	373	return ret;
	374	}
	375
fd4f99c4 BB	376	ret = pwm_adjust_config(drvdata->pwm);
	377	if (ret)
	378	return ret;
8c12ad8e	379
aa66cc66	380	regulator = devm_regulator_register(&pdev->dev,
f907a0a9	381	&drvdata->desc, &config);
aa66cc66	382	if (IS_ERR(regulator)) {
5bf59bd5 LD	383	ret = PTR_ERR(regulator);
	384	dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
	385	drvdata->desc.name, ret);
	386	return ret;
aa66cc66 CZ	387	}
	388
	389	return 0;
	390	}
	391
	392	static const struct of_device_id pwm_of_match[] = {
	393	{ .compatible = "pwm-regulator" },
	394	{ },
	395	};
	396	MODULE_DEVICE_TABLE(of, pwm_of_match);
	397
	398	static struct platform_driver pwm_regulator_driver = {
	399	.driver = {
	400	.name = "pwm-regulator",
aa66cc66 CZ	401	.of_match_table = of_match_ptr(pwm_of_match),
	402	},
	403	.probe = pwm_regulator_probe,
	404	};
	405
	406	module_platform_driver(pwm_regulator_driver);
	407
	408	MODULE_LICENSE("GPL");
	409	MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
	410	MODULE_DESCRIPTION("PWM Regulator Driver");
	411	MODULE_ALIAS("platform:pwm-regulator");