[mirror_ubuntu-bionic-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);

	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 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
a4aae5af	125	gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
27bfa889	126
1de7d802 BB	127	return pwm_enable(drvdata->pwm);
	128	}
	129
	130	static int pwm_regulator_disable(struct regulator_dev *dev)
	131	{
	132	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	133
	134	pwm_disable(drvdata->pwm);
	135
a4aae5af	136	gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
27bfa889	137
1de7d802 BB	138	return 0;
	139	}
	140
	141	static int pwm_regulator_is_enabled(struct regulator_dev *dev)
	142	{
	143	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
	144
27bfa889 AC	145	if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
	146	return false;
	147
1de7d802 BB	148	return pwm_is_enabled(drvdata->pwm);
	149	}
	150
4773be18 LJ	151	static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
	152	{
	153	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	154	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	155	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	156	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
d9070fdb	157	int min_uV = rdev->constraints->min_uV;
ea398e28 BB	158	int max_uV = rdev->constraints->max_uV;
ea398e28 BB	159	int diff_uV = max_uV - min_uV;
d9070fdb	160	struct pwm_state pstate;
ea398e28 BB	161	unsigned int diff_duty;
ea398e28 BB	162	unsigned int voltage;
4773be18	163
d9070fdb BB	164	pwm_get_state(drvdata->pwm, &pstate);
d9070fdb BB	165
ea398e28 BB	166	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
	167
	168	/*
	169	* The dutycycle for min_uV might be greater than the one for max_uV.
	170	* This is happening when the user needs an inversed polarity, but the
	171	* PWM device does not support inversing it in hardware.
	172	*/
	173	if (max_uV_duty < min_uV_duty) {
	174	voltage = min_uV_duty - voltage;
	175	diff_duty = min_uV_duty - max_uV_duty;
	176	} else {
	177	voltage = voltage - min_uV_duty;
	178	diff_duty = max_uV_duty - min_uV_duty;
	179	}
	180
	181	voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);
	182
	183	return voltage + min_uV;
4773be18 LJ	184	}
	185
	186	static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
ea398e28 BB	187	int req_min_uV, int req_max_uV,
ea398e28 BB	188	unsigned int *selector)
4773be18 LJ	189	{
4773be18 LJ	190	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
ea398e28 BB	191	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
	192	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
	193	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
ea398e28 BB	194	int min_uV = rdev->constraints->min_uV;
	195	int max_uV = rdev->constraints->max_uV;
	196	int diff_uV = max_uV - min_uV;
3f4eb39b	197	struct pwm_state pstate;
ea398e28 BB	198	unsigned int diff_duty;
ea398e28 BB	199	unsigned int dutycycle;
4773be18 LJ	200	int ret;
4773be18 LJ	201
3f4eb39b	202	pwm_init_state(drvdata->pwm, &pstate);
fd786fb0	203
ea398e28 BB	204	/*
	205	* The dutycycle for min_uV might be greater than the one for max_uV.
	206	* This is happening when the user needs an inversed polarity, but the
	207	* PWM device does not support inversing it in hardware.
	208	*/
	209	if (max_uV_duty < min_uV_duty)
	210	diff_duty = min_uV_duty - max_uV_duty;
	211	else
	212	diff_duty = max_uV_duty - min_uV_duty;
	213
	214	dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
	215	diff_duty,
	216	diff_uV);
	217
	218	if (max_uV_duty < min_uV_duty)
	219	dutycycle = min_uV_duty - dutycycle;
	220	else
	221	dutycycle = min_uV_duty + dutycycle;
	222
	223	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
4773be18	224
3f4eb39b	225	ret = pwm_apply_state(drvdata->pwm, &pstate);
4773be18	226	if (ret) {
5bf59bd5	227	dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
4773be18 LJ	228	return ret;
	229	}
	230
4773be18 LJ	231	return 0;
	232	}
	233
f9178dad	234	static struct regulator_ops pwm_regulator_voltage_table_ops = {
aa66cc66 CZ	235	.set_voltage_sel = pwm_regulator_set_voltage_sel,
	236	.get_voltage_sel = pwm_regulator_get_voltage_sel,
	237	.list_voltage = pwm_regulator_list_voltage,
	238	.map_voltage = regulator_map_voltage_iterate,
1de7d802 BB	239	.enable = pwm_regulator_enable,
	240	.disable = pwm_regulator_disable,
	241	.is_enabled = pwm_regulator_is_enabled,
aa66cc66 CZ	242	};
aa66cc66 CZ	243
4773be18 LJ	244	static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
	245	.get_voltage = pwm_regulator_get_voltage,
	246	.set_voltage = pwm_regulator_set_voltage,
1de7d802 BB	247	.enable = pwm_regulator_enable,
	248	.disable = pwm_regulator_disable,
	249	.is_enabled = pwm_regulator_is_enabled,
4773be18 LJ	250	};
4773be18 LJ	251
b6f55e74	252	static struct regulator_desc pwm_regulator_desc = {
aa66cc66	253	.name = "pwm-regulator",
aa66cc66 CZ	254	.type = REGULATOR_VOLTAGE,
	255	.owner = THIS_MODULE,
	256	.supply_name = "pwm",
	257	};
	258
f9178dad LJ	259	static int pwm_regulator_init_table(struct platform_device *pdev,
	260	struct pwm_regulator_data *drvdata)
	261	{
	262	struct device_node *np = pdev->dev.of_node;
	263	struct pwm_voltages *duty_cycle_table;
60cb65eb	264	unsigned int length = 0;
f9178dad LJ	265	int ret;
	266
	267	of_find_property(np, "voltage-table", &length);
	268
	269	if ((length < sizeof(*duty_cycle_table)) \|\|
	270	(length % sizeof(*duty_cycle_table))) {
5bf59bd5	271	dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n",
f9178dad LJ	272	length);
	273	return -EINVAL;
	274	}
	275
	276	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
	277	if (!duty_cycle_table)
	278	return -ENOMEM;
	279
	280	ret = of_property_read_u32_array(np, "voltage-table",
	281	(u32 *)duty_cycle_table,
	282	length / sizeof(u32));
	283	if (ret) {
5bf59bd5	284	dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret);
f9178dad LJ	285	return ret;
	286	}
	287
87248991	288	drvdata->state = -EINVAL;
f9178dad	289	drvdata->duty_cycle_table = duty_cycle_table;
f907a0a9 LD	290	memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
	291	sizeof(drvdata->ops));
	292	drvdata->desc.ops = &drvdata->ops;
	293	drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table);
f9178dad LJ	294
	295	return 0;
	296	}
	297
4773be18 LJ	298	static int pwm_regulator_init_continuous(struct platform_device *pdev,
	299	struct pwm_regulator_data *drvdata)
	300	{
ea398e28 BB	301	u32 dutycycle_range[2] = { 0, 100 };
	302	u32 dutycycle_unit = 100;
	303
f907a0a9 LD	304	memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
	305	sizeof(drvdata->ops));
	306	drvdata->desc.ops = &drvdata->ops;
	307	drvdata->desc.continuous_voltage_range = true;
4773be18	308
ea398e28 BB	309	of_property_read_u32_array(pdev->dev.of_node,
	310	"pwm-dutycycle-range",
	311	dutycycle_range, 2);
	312	of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
	313	&dutycycle_unit);
	314
	315	if (dutycycle_range[0] > dutycycle_unit \|\|
	316	dutycycle_range[1] > dutycycle_unit)
	317	return -EINVAL;
	318
	319	drvdata->continuous.dutycycle_unit = dutycycle_unit;
	320	drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
	321	drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];
	322
4773be18 LJ	323	return 0;
	324	}
	325
aa66cc66 CZ	326	static int pwm_regulator_probe(struct platform_device *pdev)
aa66cc66 CZ	327	{
5ad2cb14	328	const struct regulator_init_data *init_data;
aa66cc66	329	struct pwm_regulator_data *drvdata;
aa66cc66 CZ	330	struct regulator_dev *regulator;
	331	struct regulator_config config = { };
	332	struct device_node *np = pdev->dev.of_node;
27bfa889	333	enum gpiod_flags gpio_flags;
f9178dad	334	int ret;
aa66cc66 CZ	335
	336	if (!np) {
	337	dev_err(&pdev->dev, "Device Tree node missing\n");
	338	return -EINVAL;
	339	}
	340
	341	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
	342	if (!drvdata)
	343	return -ENOMEM;
	344
f907a0a9 LD	345	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
f907a0a9 LD	346
4773be18	347	if (of_find_property(np, "voltage-table", NULL))
f9178dad	348	ret = pwm_regulator_init_table(pdev, drvdata);
4773be18 LJ	349	else
	350	ret = pwm_regulator_init_continuous(pdev, drvdata);
	351	if (ret)
	352	return ret;
aa66cc66	353
5ad2cb14	354	init_data = of_get_regulator_init_data(&pdev->dev, np,
f907a0a9	355	&drvdata->desc);
5ad2cb14	356	if (!init_data)
aa66cc66 CZ	357	return -ENOMEM;
	358
	359	config.of_node = np;
	360	config.dev = &pdev->dev;
	361	config.driver_data = drvdata;
5ad2cb14	362	config.init_data = init_data;
aa66cc66 CZ	363
	364	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
	365	if (IS_ERR(drvdata->pwm)) {
5bf59bd5 LD	366	ret = PTR_ERR(drvdata->pwm);
	367	dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret);
	368	return ret;
aa66cc66 CZ	369	}
aa66cc66 CZ	370
27bfa889 AC	371	if (init_data->constraints.boot_on \|\| init_data->constraints.always_on)
	372	gpio_flags = GPIOD_OUT_HIGH;
	373	else
	374	gpio_flags = GPIOD_OUT_LOW;
	375	drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
	376	gpio_flags);
	377	if (IS_ERR(drvdata->enb_gpio)) {
	378	ret = PTR_ERR(drvdata->enb_gpio);
	379	dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret);
	380	return ret;
	381	}
	382
fd4f99c4 BB	383	ret = pwm_adjust_config(drvdata->pwm);
	384	if (ret)
	385	return ret;
8c12ad8e	386
aa66cc66	387	regulator = devm_regulator_register(&pdev->dev,
f907a0a9	388	&drvdata->desc, &config);
aa66cc66	389	if (IS_ERR(regulator)) {
5bf59bd5 LD	390	ret = PTR_ERR(regulator);
	391	dev_err(&pdev->dev, "Failed to register regulator %s: %d\n",
	392	drvdata->desc.name, ret);
	393	return ret;
aa66cc66 CZ	394	}
	395
	396	return 0;
	397	}
	398
	399	static const struct of_device_id pwm_of_match[] = {
	400	{ .compatible = "pwm-regulator" },
	401	{ },
	402	};
	403	MODULE_DEVICE_TABLE(of, pwm_of_match);
	404
	405	static struct platform_driver pwm_regulator_driver = {
	406	.driver = {
	407	.name = "pwm-regulator",
aa66cc66 CZ	408	.of_match_table = of_match_ptr(pwm_of_match),
	409	},
	410	.probe = pwm_regulator_probe,
	411	};
	412
	413	module_platform_driver(pwm_regulator_driver);
	414
	415	MODULE_LICENSE("GPL");
	416	MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
	417	MODULE_DESCRIPTION("PWM Regulator Driver");
	418	MODULE_ALIAS("platform:pwm-regulator");