[linux-2.6-block.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_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;
	unsigned int ramp_delay = rdev->constraints->ramp_delay;
	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;
	int old_uV = pwm_regulator_get_voltage(rdev);
	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;
	}

	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(req_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->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
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	24
ea398e28 BB	25	struct pwm_continuous_reg_data {
	26	unsigned int min_uV_dutycycle;
	27	unsigned int max_uV_dutycycle;
	28	unsigned int dutycycle_unit;
	29	};
	30
aa66cc66	31	struct pwm_regulator_data {
4773be18	32	/* Shared */
aa66cc66	33	struct pwm_device *pwm;
4773be18 LJ	34
	35	/* Voltage table */
	36	struct pwm_voltages *duty_cycle_table;
f907a0a9	37
ea398e28 BB	38	/* Continuous mode info */
	39	struct pwm_continuous_reg_data continuous;
	40
f907a0a9 LD	41	/* regulator descriptor */
	42	struct regulator_desc desc;
	43
	44	/* Regulator ops */
	45	struct regulator_ops ops;
	46
aa66cc66	47	int state;
4773be18	48
27bfa889 AC	49	/* Enable GPIO */
27bfa889 AC	50	struct gpio_desc *enb_gpio;
aa66cc66 CZ	51	};
	52
	53	struct pwm_voltages {
	54	unsigned int uV;
	55	unsigned int dutycycle;
	56	};
	57
4773be18 LJ	58	/**
	59	* Voltage table call-backs
	60	*/
87248991 BB	61	static void pwm_regulator_init_state(struct regulator_dev *rdev)
	62	{
	63	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
	64	struct pwm_state pwm_state;
	65	unsigned int dutycycle;
	66	int i;
	67
	68	pwm_get_state(drvdata->pwm, &pwm_state);
	69	dutycycle = pwm_get_relative_duty_cycle(&pwm_state, 100);
	70
	71	for (i = 0; i < rdev->desc->n_voltages; i++) {
	72	if (dutycycle == drvdata->duty_cycle_table[i].dutycycle) {
	73	drvdata->state = i;
	74	return;
	75	}
	76	}
	77	}
	78
ab101e35	79	static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
aa66cc66	80	{
ab101e35	81	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66	82
87248991 BB	83	if (drvdata->state < 0)
	84	pwm_regulator_init_state(rdev);
	85
aa66cc66 CZ	86	return drvdata->state;
	87	}
	88
ab101e35	89	static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
aa66cc66 CZ	90	unsigned selector)
aa66cc66 CZ	91	{
ab101e35	92	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
3f4eb39b	93	struct pwm_state pstate;
aa66cc66 CZ	94	int ret;
aa66cc66 CZ	95
3f4eb39b BB	96	pwm_init_state(drvdata->pwm, &pstate);
	97	pwm_set_relative_duty_cycle(&pstate,
	98	drvdata->duty_cycle_table[selector].dutycycle, 100);
aa66cc66	99
3f4eb39b	100	ret = pwm_apply_state(drvdata->pwm, &pstate);
aa66cc66	101	if (ret) {
5bf59bd5	102	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
aa66cc66 CZ	103	return ret;
	104	}
	105
	106	drvdata->state = selector;
	107
aa66cc66 CZ	108	return 0;
	109	}
	110
ab101e35	111	static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
aa66cc66 CZ	112	unsigned selector)
aa66cc66 CZ	113	{
ab101e35	114	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
aa66cc66	115
ab101e35	116	if (selector >= rdev->desc->n_voltages)
aa66cc66 CZ	117	return -EINVAL;
	118
	119	return drvdata->duty_cycle_table[selector].uV;
	120	}
4773be18	121
1de7d802 BB	122	static int pwm_regulator_enable(struct regulator_dev *dev)
	123	{
	124	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	125
27bfa889 AC	126	if (drvdata->enb_gpio)
	127	gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
	128
1de7d802 BB	129	return pwm_enable(drvdata->pwm);
	130	}
	131
	132	static int pwm_regulator_disable(struct regulator_dev *dev)
	133	{
	134	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	135
	136	pwm_disable(drvdata->pwm);
	137
27bfa889 AC	138	if (drvdata->enb_gpio)
	139	gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
	140
1de7d802 BB	141	return 0;
	142	}
	143
	144	static int pwm_regulator_is_enabled(struct regulator_dev *dev)
	145	{
	146	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	147
27bfa889 AC	148	if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
	149	return false;
	150
1de7d802 BB	151	return pwm_is_enabled(drvdata->pwm);
	152	}
	153
4773be18 LJ	154	static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
	155	{
	156	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	157	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	158	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	159	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
d9070fdb	160	int min_uV = rdev->constraints->min_uV;
ea398e28 BB	161	int max_uV = rdev->constraints->max_uV;
ea398e28 BB	162	int diff_uV = max_uV - min_uV;
d9070fdb	163	struct pwm_state pstate;
ea398e28 BB	164	unsigned int diff_duty;
ea398e28 BB	165	unsigned int voltage;
4773be18	166
d9070fdb BB	167	pwm_get_state(drvdata->pwm, &pstate);
d9070fdb BB	168
ea398e28 BB	169	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
	170
	171	/*
	172	* The dutycycle for min_uV might be greater than the one for max_uV.
	173	* This is happening when the user needs an inversed polarity, but the
	174	* PWM device does not support inversing it in hardware.
	175	*/
	176	if (max_uV_duty < min_uV_duty) {
	177	voltage = min_uV_duty - voltage;
	178	diff_duty = min_uV_duty - max_uV_duty;
	179	} else {
	180	voltage = voltage - min_uV_duty;
	181	diff_duty = max_uV_duty - min_uV_duty;
	182	}
	183
	184	voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);
	185
	186	return voltage + min_uV;
4773be18 LJ	187	}
	188
	189	static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
ea398e28 BB	190	int req_min_uV, int req_max_uV,
ea398e28 BB	191	unsigned int *selector)
4773be18 LJ	192	{
4773be18 LJ	193	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	194	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	195	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	196	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
4773be18	197	unsigned int ramp_delay = rdev->constraints->ramp_delay;
ea398e28 BB	198	int min_uV = rdev->constraints->min_uV;
	199	int max_uV = rdev->constraints->max_uV;
	200	int diff_uV = max_uV - min_uV;
3f4eb39b	201	struct pwm_state pstate;
c2588393	202	int old_uV = pwm_regulator_get_voltage(rdev);
ea398e28 BB	203	unsigned int diff_duty;
ea398e28 BB	204	unsigned int dutycycle;
4773be18 LJ	205	int ret;
4773be18 LJ	206
3f4eb39b	207	pwm_init_state(drvdata->pwm, &pstate);
fd786fb0	208
ea398e28 BB	209	/*
	210	* The dutycycle for min_uV might be greater than the one for max_uV.
	211	* This is happening when the user needs an inversed polarity, but the
	212	* PWM device does not support inversing it in hardware.
	213	*/
	214	if (max_uV_duty < min_uV_duty)
	215	diff_duty = min_uV_duty - max_uV_duty;
	216	else
	217	diff_duty = max_uV_duty - min_uV_duty;
	218
	219	dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
	220	diff_duty,
	221	diff_uV);
	222
	223	if (max_uV_duty < min_uV_duty)
	224	dutycycle = min_uV_duty - dutycycle;
	225	else
	226	dutycycle = min_uV_duty + dutycycle;
	227
	228	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
4773be18	229
3f4eb39b	230	ret = pwm_apply_state(drvdata->pwm, &pstate);
4773be18	231	if (ret) {
5bf59bd5	232	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
4773be18 LJ	233	return ret;
	234	}
	235
c2588393 DA	236	if ((ramp_delay == 0) \|\| !pwm_regulator_is_enabled(rdev))
	237	return 0;
	238
	239	/* Ramp delay is in uV/uS. Adjust to uS and delay */
ea398e28	240	ramp_delay = DIV_ROUND_UP(abs(req_min_uV - old_uV), ramp_delay);
c2588393	241	usleep_range(ramp_delay, ramp_delay + DIV_ROUND_UP(ramp_delay, 10));
4773be18 LJ	242
	243	return 0;
	244	}
	245
f9178dad	246	static struct regulator_ops pwm_regulator_voltage_table_ops = {
aa66cc66 CZ	247	.set_voltage_sel = pwm_regulator_set_voltage_sel,
	248	.get_voltage_sel = pwm_regulator_get_voltage_sel,
	249	.list_voltage = pwm_regulator_list_voltage,
	250	.map_voltage = regulator_map_voltage_iterate,
1de7d802 BB	251	.enable = pwm_regulator_enable,
	252	.disable = pwm_regulator_disable,
	253	.is_enabled = pwm_regulator_is_enabled,
aa66cc66 CZ	254	};
aa66cc66 CZ	255
4773be18 LJ	256	static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
	257	.get_voltage = pwm_regulator_get_voltage,
	258	.set_voltage = pwm_regulator_set_voltage,
1de7d802 BB	259	.enable = pwm_regulator_enable,
	260	.disable = pwm_regulator_disable,
	261	.is_enabled = pwm_regulator_is_enabled,
4773be18 LJ	262	};
4773be18 LJ	263
b6f55e74	264	static struct regulator_desc pwm_regulator_desc = {
aa66cc66	265	.name = "pwm-regulator",
aa66cc66 CZ	266	.type = REGULATOR_VOLTAGE,
	267	.owner = THIS_MODULE,
	268	.supply_name = "pwm",
	269	};
	270
f9178dad LJ	271	static int pwm_regulator_init_table(struct platform_device *pdev,
	272	struct pwm_regulator_data *drvdata)
	273	{
	274	struct device_node *np = pdev->dev.of_node;
	275	struct pwm_voltages *duty_cycle_table;
60cb65eb	276	unsigned int length = 0;
f9178dad LJ	277	int ret;
	278
	279	of_find_property(np, "voltage-table", &length);
	280
	281	if ((length < sizeof(*duty_cycle_table)) \|\|
	282	(length % sizeof(*duty_cycle_table))) {
5bf59bd5	283	dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
f9178dad LJ	284	length);
	285	return -EINVAL;
	286	}
	287
	288	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
	289	if (!duty_cycle_table)
	290	return -ENOMEM;
	291
	292	ret = of_property_read_u32_array(np, "voltage-table",
	293	(u32 *)duty_cycle_table,
	294	length / sizeof(u32));
	295	if (ret) {
5bf59bd5	296	dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
f9178dad LJ	297	return ret;
	298	}
	299
87248991	300	drvdata->state = -EINVAL;
f9178dad	301	drvdata->duty_cycle_table = duty_cycle_table;
f907a0a9 LD	302	memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
	303	sizeof(drvdata->ops));
	304	drvdata->desc.ops = &drvdata->ops;
	305	drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table);
f9178dad LJ	306
	307	return 0;
	308	}
	309
4773be18 LJ	310	static int pwm_regulator_init_continuous(struct platform_device *pdev,
	311	struct pwm_regulator_data *drvdata)
	312	{
ea398e28 BB	313	u32 dutycycle_range[2] = { 0, 100 };
	314	u32 dutycycle_unit = 100;
	315
f907a0a9 LD	316	memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
	317	sizeof(drvdata->ops));
	318	drvdata->desc.ops = &drvdata->ops;
	319	drvdata->desc.continuous_voltage_range = true;
4773be18	320
ea398e28 BB	321	of_property_read_u32_array(pdev->dev.of_node,
	322	"pwm-dutycycle-range",
	323	dutycycle_range, 2);
	324	of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
	325	&dutycycle_unit);
	326
	327	if (dutycycle_range[0] > dutycycle_unit \|\|
	328	dutycycle_range[1] > dutycycle_unit)
	329	return -EINVAL;
	330
	331	drvdata->continuous.dutycycle_unit = dutycycle_unit;
	332	drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
	333	drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];
	334
4773be18 LJ	335	return 0;
	336	}
	337
aa66cc66 CZ	338	static int pwm_regulator_probe(struct platform_device *pdev)
aa66cc66 CZ	339	{
5ad2cb14	340	const struct regulator_init_data *init_data;
aa66cc66	341	struct pwm_regulator_data *drvdata;
aa66cc66 CZ	342	struct regulator_dev *regulator;
	343	struct regulator_config config = { };
	344	struct device_node *np = pdev->dev.of_node;
27bfa889	345	enum gpiod_flags gpio_flags;
f9178dad	346	int ret;
aa66cc66 CZ	347
	348	if (!np) {
	349	dev_err(&pdev->dev, "Device Tree node missing\n");
	350	return -EINVAL;
	351	}
	352
	353	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
	354	if (!drvdata)
	355	return -ENOMEM;
	356
f907a0a9 LD	357	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
f907a0a9 LD	358
4773be18	359	if (of_find_property(np, "voltage-table", NULL))
f9178dad	360	ret = pwm_regulator_init_table(pdev, drvdata);
4773be18 LJ	361	else
	362	ret = pwm_regulator_init_continuous(pdev, drvdata);
	363	if (ret)
	364	return ret;
aa66cc66	365
5ad2cb14	366	init_data = of_get_regulator_init_data(&pdev->dev, np,
f907a0a9	367	&drvdata->desc);
5ad2cb14	368	if (!init_data)
aa66cc66 CZ	369	return -ENOMEM;
	370
	371	config.of_node = np;
	372	config.dev = &pdev->dev;
	373	config.driver_data = drvdata;
5ad2cb14	374	config.init_data = init_data;
aa66cc66 CZ	375
	376	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
	377	if (IS_ERR(drvdata->pwm)) {
5bf59bd5 LD	378	ret = PTR_ERR(drvdata->pwm);
	379	dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
	380	return ret;
aa66cc66 CZ	381	}
aa66cc66 CZ	382
27bfa889 AC	383	if (init_data->constraints.boot_on \|\| init_data->constraints.always_on)
	384	gpio_flags = GPIOD_OUT_HIGH;
	385	else
	386	gpio_flags = GPIOD_OUT_LOW;
	387	drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
	388	gpio_flags);
	389	if (IS_ERR(drvdata->enb_gpio)) {
	390	ret = PTR_ERR(drvdata->enb_gpio);
	391	dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
	392	return ret;
	393	}
	394
fd4f99c4 BB	395	ret = pwm_adjust_config(drvdata->pwm);
	396	if (ret)
	397	return ret;
8c12ad8e	398
aa66cc66	399	regulator = devm_regulator_register(&pdev->dev,
f907a0a9	400	&drvdata->desc, &config);
aa66cc66	401	if (IS_ERR(regulator)) {
5bf59bd5 LD	402	ret = PTR_ERR(regulator);
	403	dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
	404	drvdata->desc.name, ret);
	405	return ret;
aa66cc66 CZ	406	}
	407
	408	return 0;
	409	}
	410
	411	static const struct of_device_id pwm_of_match[] = {
	412	{ .compatible = "pwm-regulator" },
	413	{ },
	414	};
	415	MODULE_DEVICE_TABLE(of, pwm_of_match);
	416
	417	static struct platform_driver pwm_regulator_driver = {
	418	.driver = {
	419	.name = "pwm-regulator",
aa66cc66 CZ	420	.of_match_table = of_match_ptr(pwm_of_match),
	421	},
	422	.probe = pwm_regulator_probe,
	423	};
	424
	425	module_platform_driver(pwm_regulator_driver);
	426
	427	MODULE_LICENSE("GPL");
	428	MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
	429	MODULE_DESCRIPTION("PWM Regulator Driver");
	430	MODULE_ALIAS("platform:pwm-regulator");