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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Regulator driver for PWM Regulators
  4 *
  5 * Copyright (C) 2014 - STMicroelectronics Inc.
  6 *
  7 * Author: Lee Jones <lee.jones@linaro.org>
 
 
 
 
  8 */
  9
 
 10#include <linux/module.h>
 11#include <linux/init.h>
 12#include <linux/err.h>
 13#include <linux/platform_device.h>
 14#include <linux/regulator/driver.h>
 15#include <linux/regulator/machine.h>
 16#include <linux/regulator/of_regulator.h>
 17#include <linux/of.h>
 
 18#include <linux/pwm.h>
 19#include <linux/gpio/consumer.h>
 20
 21struct pwm_continuous_reg_data {
 22	unsigned int min_uV_dutycycle;
 23	unsigned int max_uV_dutycycle;
 24	unsigned int dutycycle_unit;
 25};
 26
 27struct pwm_regulator_data {
 28	/*  Shared */
 29	struct pwm_device *pwm;
 30
 31	/* Voltage table */
 32	struct pwm_voltages *duty_cycle_table;
 33
 34	/* Continuous mode info */
 35	struct pwm_continuous_reg_data continuous;
 36
 37	/* regulator descriptor */
 38	struct regulator_desc desc;
 39
 
 
 
 40	int state;
 41
 42	/* Enable GPIO */
 43	struct gpio_desc *enb_gpio;
 44};
 45
 46struct pwm_voltages {
 47	unsigned int uV;
 48	unsigned int dutycycle;
 49};
 50
 51/*
 52 * Voltage table call-backs
 53 */
 54static void pwm_regulator_init_state(struct regulator_dev *rdev)
 55{
 56	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
 57	struct pwm_state pwm_state;
 58	unsigned int dutycycle;
 59	int i;
 60
 61	pwm_get_state(drvdata->pwm, &pwm_state);
 62	dutycycle = pwm_get_relative_duty_cycle(&pwm_state, 100);
 63
 64	for (i = 0; i < rdev->desc->n_voltages; i++) {
 65		if (dutycycle == drvdata->duty_cycle_table[i].dutycycle) {
 66			drvdata->state = i;
 67			return;
 68		}
 69	}
 70}
 71
 72static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
 73{
 74	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
 75
 76	if (drvdata->state < 0)
 77		pwm_regulator_init_state(rdev);
 78
 79	return drvdata->state;
 80}
 81
 82static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
 83					 unsigned selector)
 84{
 85	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
 86	struct pwm_state pstate;
 
 87	int ret;
 88
 89	pwm_init_state(drvdata->pwm, &pstate);
 90	pwm_set_relative_duty_cycle(&pstate,
 91			drvdata->duty_cycle_table[selector].dutycycle, 100);
 
 92
 93	ret = pwm_apply_might_sleep(drvdata->pwm, &pstate);
 94	if (ret) {
 95		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
 96		return ret;
 97	}
 98
 99	drvdata->state = selector;
100
101	return 0;
102}
103
104static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
105				      unsigned selector)
106{
107	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
108
109	if (selector >= rdev->desc->n_voltages)
110		return -EINVAL;
111
112	return drvdata->duty_cycle_table[selector].uV;
113}
114
115static int pwm_regulator_enable(struct regulator_dev *dev)
116{
117	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
118
119	gpiod_set_value_cansleep(drvdata->enb_gpio, 1);
120
121	return pwm_enable(drvdata->pwm);
122}
123
124static int pwm_regulator_disable(struct regulator_dev *dev)
125{
126	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
127
128	pwm_disable(drvdata->pwm);
129
130	gpiod_set_value_cansleep(drvdata->enb_gpio, 0);
131
132	return 0;
133}
134
135static int pwm_regulator_is_enabled(struct regulator_dev *dev)
136{
137	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
138
139	if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio))
140		return false;
141
142	return pwm_is_enabled(drvdata->pwm);
143}
144
145static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
 
 
 
146{
147	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
148	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
149	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
150	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
151	int min_uV = rdev->constraints->min_uV;
152	int max_uV = rdev->constraints->max_uV;
153	int diff_uV = max_uV - min_uV;
154	struct pwm_state pstate;
155	unsigned int diff_duty;
156	unsigned int voltage;
157
158	pwm_get_state(drvdata->pwm, &pstate);
159
160	if (!pstate.enabled) {
161		if (pstate.polarity == PWM_POLARITY_INVERSED)
162			pstate.duty_cycle = pstate.period;
163		else
164			pstate.duty_cycle = 0;
165	}
166
167	voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit);
168	if (voltage < min(max_uV_duty, min_uV_duty) ||
169	    voltage > max(max_uV_duty, min_uV_duty))
170		return -ENOTRECOVERABLE;
171
172	/*
173	 * The dutycycle for min_uV might be greater than the one for max_uV.
174	 * This is happening when the user needs an inversed polarity, but the
175	 * PWM device does not support inversing it in hardware.
176	 */
177	if (max_uV_duty < min_uV_duty) {
178		voltage = min_uV_duty - voltage;
179		diff_duty = min_uV_duty - max_uV_duty;
180	} else {
181		voltage = voltage - min_uV_duty;
182		diff_duty = max_uV_duty - min_uV_duty;
183	}
184
185	voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty);
 
 
186
187	return voltage + min_uV;
188}
189
190static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
191				     int req_min_uV, int req_max_uV,
192				     unsigned int *selector)
193{
194	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
195	unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle;
196	unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle;
197	unsigned int duty_unit = drvdata->continuous.dutycycle_unit;
198	int min_uV = rdev->constraints->min_uV;
199	int max_uV = rdev->constraints->max_uV;
200	int diff_uV = max_uV - min_uV;
201	struct pwm_state pstate;
202	unsigned int diff_duty;
203	unsigned int dutycycle;
204	int ret;
205
206	pwm_init_state(drvdata->pwm, &pstate);
207
208	/*
209	 * The dutycycle for min_uV might be greater than the one for max_uV.
210	 * This is happening when the user needs an inversed polarity, but the
211	 * PWM device does not support inversing it in hardware.
212	 */
213	if (max_uV_duty < min_uV_duty)
214		diff_duty = min_uV_duty - max_uV_duty;
215	else
216		diff_duty = max_uV_duty - min_uV_duty;
217
218	dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) *
219					  diff_duty,
220					  diff_uV);
221
222	if (max_uV_duty < min_uV_duty)
223		dutycycle = min_uV_duty - dutycycle;
224	else
225		dutycycle = min_uV_duty + dutycycle;
226
227	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
 
 
 
 
228
229	ret = pwm_apply_might_sleep(drvdata->pwm, &pstate);
230	if (ret) {
231		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
232		return ret;
233	}
 
 
 
 
234
235	return 0;
236}
237
238static const struct regulator_ops pwm_regulator_voltage_table_ops = {
239	.set_voltage_sel = pwm_regulator_set_voltage_sel,
240	.get_voltage_sel = pwm_regulator_get_voltage_sel,
241	.list_voltage    = pwm_regulator_list_voltage,
242	.map_voltage     = regulator_map_voltage_iterate,
243	.enable          = pwm_regulator_enable,
244	.disable         = pwm_regulator_disable,
245	.is_enabled      = pwm_regulator_is_enabled,
246};
247
248static const struct regulator_ops pwm_regulator_voltage_continuous_ops = {
249	.get_voltage = pwm_regulator_get_voltage,
250	.set_voltage = pwm_regulator_set_voltage,
251	.enable          = pwm_regulator_enable,
252	.disable         = pwm_regulator_disable,
253	.is_enabled      = pwm_regulator_is_enabled,
254};
255
256static const struct regulator_desc pwm_regulator_desc = {
257	.name		= "pwm-regulator",
258	.type		= REGULATOR_VOLTAGE,
259	.owner		= THIS_MODULE,
260	.supply_name    = "pwm",
261};
262
263static int pwm_regulator_init_table(struct platform_device *pdev,
264				    struct pwm_regulator_data *drvdata)
265{
266	struct device_node *np = pdev->dev.of_node;
267	struct pwm_voltages *duty_cycle_table;
268	unsigned int length = 0;
269	int ret;
270
271	of_find_property(np, "voltage-table", &length);
272
273	if ((length < sizeof(*duty_cycle_table)) ||
274	    (length % sizeof(*duty_cycle_table)))
275		return dev_err_probe(&pdev->dev, -EINVAL,
276				     "voltage-table length(%d) is invalid\n",
277				     length);
 
 
278
279	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
280	if (!duty_cycle_table)
281		return -ENOMEM;
282
283	ret = of_property_read_u32_array(np, "voltage-table",
284					 (u32 *)duty_cycle_table,
285					 length / sizeof(u32));
286	if (ret)
287		return dev_err_probe(&pdev->dev, ret,
288				     "Failed to read voltage-table\n");
 
289
290	drvdata->state			= -ENOTRECOVERABLE;
291	drvdata->duty_cycle_table	= duty_cycle_table;
292	drvdata->desc.ops = &pwm_regulator_voltage_table_ops;
 
 
293	drvdata->desc.n_voltages	= length / sizeof(*duty_cycle_table);
294
295	return 0;
296}
297
298static int pwm_regulator_init_continuous(struct platform_device *pdev,
299					 struct pwm_regulator_data *drvdata)
300{
301	u32 dutycycle_range[2] = { 0, 100 };
302	u32 dutycycle_unit = 100;
303
304	drvdata->desc.ops = &pwm_regulator_voltage_continuous_ops;
305	drvdata->desc.continuous_voltage_range = true;
306
307	of_property_read_u32_array(pdev->dev.of_node,
308				   "pwm-dutycycle-range",
309				   dutycycle_range, 2);
310	of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit",
311			     &dutycycle_unit);
312
313	if (dutycycle_range[0] > dutycycle_unit ||
314	    dutycycle_range[1] > dutycycle_unit)
315		return -EINVAL;
316
317	drvdata->continuous.dutycycle_unit = dutycycle_unit;
318	drvdata->continuous.min_uV_dutycycle = dutycycle_range[0];
319	drvdata->continuous.max_uV_dutycycle = dutycycle_range[1];
320
321	return 0;
322}
323
324static int pwm_regulator_init_boot_on(struct platform_device *pdev,
325				      struct pwm_regulator_data *drvdata,
326				      const struct regulator_init_data *init_data)
327{
328	struct pwm_state pstate;
329
330	if (!init_data->constraints.boot_on || drvdata->enb_gpio)
331		return 0;
332
333	pwm_get_state(drvdata->pwm, &pstate);
334	if (pstate.enabled)
335		return 0;
336
337	/*
338	 * Update the duty cycle so the output does not change
339	 * when the regulator core enables the regulator (and
340	 * thus the PWM channel).
341	 */
342	if (pstate.polarity == PWM_POLARITY_INVERSED)
343		pstate.duty_cycle = pstate.period;
344	else
345		pstate.duty_cycle = 0;
346
347	return pwm_apply_might_sleep(drvdata->pwm, &pstate);
348}
349
350static int pwm_regulator_probe(struct platform_device *pdev)
351{
352	const struct regulator_init_data *init_data;
353	struct pwm_regulator_data *drvdata;
354	struct regulator_dev *regulator;
355	struct regulator_config config = { };
356	struct device_node *np = pdev->dev.of_node;
357	enum gpiod_flags gpio_flags;
358	int ret;
359
360	if (!np)
361		return dev_err_probe(&pdev->dev, -EINVAL,
362				     "Device Tree node missing\n");
 
363
364	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
365	if (!drvdata)
366		return -ENOMEM;
367
368	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
369
370	if (of_property_present(np, "voltage-table"))
371		ret = pwm_regulator_init_table(pdev, drvdata);
372	else
373		ret = pwm_regulator_init_continuous(pdev, drvdata);
374	if (ret)
375		return ret;
376
377	init_data = of_get_regulator_init_data(&pdev->dev, np,
378					       &drvdata->desc);
379	if (!init_data)
380		return -ENOMEM;
381
382	config.of_node = np;
383	config.dev = &pdev->dev;
384	config.driver_data = drvdata;
385	config.init_data = init_data;
386
387	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
388	if (IS_ERR(drvdata->pwm))
389		return dev_err_probe(&pdev->dev, PTR_ERR(drvdata->pwm),
390				     "Failed to get PWM\n");
391
392	if (init_data->constraints.boot_on || init_data->constraints.always_on)
393		gpio_flags = GPIOD_OUT_HIGH;
394	else
395		gpio_flags = GPIOD_OUT_LOW;
396	drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
397						    gpio_flags);
398	if (IS_ERR(drvdata->enb_gpio)) {
399		ret = PTR_ERR(drvdata->enb_gpio);
400		return dev_err_probe(&pdev->dev, ret, "Failed to get enable GPIO\n");
401	}
402
403	ret = pwm_adjust_config(drvdata->pwm);
404	if (ret)
405		return ret;
406
407	ret = pwm_regulator_init_boot_on(pdev, drvdata, init_data);
408	if (ret)
409		return dev_err_probe(&pdev->dev, ret,
410				     "Failed to apply boot_on settings\n");
411
412	regulator = devm_regulator_register(&pdev->dev,
413					    &drvdata->desc, &config);
414	if (IS_ERR(regulator)) {
415		ret = PTR_ERR(regulator);
416		return dev_err_probe(&pdev->dev, ret,
417				     "Failed to register regulator %s\n",
418				     drvdata->desc.name);
419	}
420
421	return 0;
422}
423
424static const struct of_device_id __maybe_unused pwm_of_match[] = {
425	{ .compatible = "pwm-regulator" },
426	{ },
427};
428MODULE_DEVICE_TABLE(of, pwm_of_match);
429
430static struct platform_driver pwm_regulator_driver = {
431	.driver = {
432		.name		= "pwm-regulator",
433		.probe_type	= PROBE_PREFER_ASYNCHRONOUS,
434		.of_match_table = of_match_ptr(pwm_of_match),
435	},
436	.probe = pwm_regulator_probe,
437};
438
439module_platform_driver(pwm_regulator_driver);
440
441MODULE_LICENSE("GPL");
442MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
443MODULE_DESCRIPTION("PWM Regulator Driver");
444MODULE_ALIAS("platform:pwm-regulator");
v4.6
 
  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/delay.h>
 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>
 
 
 
 
 
 
 
 23
 24struct pwm_regulator_data {
 25	/*  Shared */
 26	struct pwm_device *pwm;
 27
 28	/* Voltage table */
 29	struct pwm_voltages *duty_cycle_table;
 30
 
 
 
 31	/* regulator descriptor */
 32	struct regulator_desc desc;
 33
 34	/* Regulator ops */
 35	struct regulator_ops ops;
 36
 37	int state;
 38
 39	/* Continuous voltage */
 40	int volt_uV;
 41};
 42
 43struct pwm_voltages {
 44	unsigned int uV;
 45	unsigned int dutycycle;
 46};
 47
 48/**
 49 * Voltage table call-backs
 50 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 51static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev)
 52{
 53	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
 54
 
 
 
 55	return drvdata->state;
 56}
 57
 58static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev,
 59					 unsigned selector)
 60{
 61	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
 62	unsigned int pwm_reg_period;
 63	int dutycycle;
 64	int ret;
 65
 66	pwm_reg_period = pwm_get_period(drvdata->pwm);
 67
 68	dutycycle = (pwm_reg_period *
 69		    drvdata->duty_cycle_table[selector].dutycycle) / 100;
 70
 71	ret = pwm_config(drvdata->pwm, dutycycle, pwm_reg_period);
 72	if (ret) {
 73		dev_err(&rdev->dev, "Failed to configure PWM\n");
 74		return ret;
 75	}
 76
 77	drvdata->state = selector;
 78
 79	return 0;
 80}
 81
 82static int pwm_regulator_list_voltage(struct regulator_dev *rdev,
 83				      unsigned selector)
 84{
 85	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
 86
 87	if (selector >= rdev->desc->n_voltages)
 88		return -EINVAL;
 89
 90	return drvdata->duty_cycle_table[selector].uV;
 91}
 92
 93static int pwm_regulator_enable(struct regulator_dev *dev)
 94{
 95	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
 96
 
 
 97	return pwm_enable(drvdata->pwm);
 98}
 99
100static int pwm_regulator_disable(struct regulator_dev *dev)
101{
102	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
103
104	pwm_disable(drvdata->pwm);
105
 
 
106	return 0;
107}
108
109static int pwm_regulator_is_enabled(struct regulator_dev *dev)
110{
111	struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev);
112
 
 
 
113	return pwm_is_enabled(drvdata->pwm);
114}
115
116/**
117 * Continuous voltage call-backs
118 */
119static int pwm_voltage_to_duty_cycle_percentage(struct regulator_dev *rdev, int req_uV)
120{
 
 
 
 
121	int min_uV = rdev->constraints->min_uV;
122	int max_uV = rdev->constraints->max_uV;
123	int diff = max_uV - min_uV;
 
 
 
 
 
 
 
 
 
 
 
 
124
125	return ((req_uV * 100) - (min_uV * 100)) / diff;
126}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
127
128static int pwm_regulator_get_voltage(struct regulator_dev *rdev)
129{
130	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
131
132	return drvdata->volt_uV;
133}
134
135static int pwm_regulator_set_voltage(struct regulator_dev *rdev,
136					int min_uV, int max_uV,
137					unsigned *selector)
138{
139	struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev);
140	unsigned int ramp_delay = rdev->constraints->ramp_delay;
141	unsigned int period = pwm_get_period(drvdata->pwm);
142	int duty_cycle;
 
 
 
 
 
 
143	int ret;
144
145	duty_cycle = pwm_voltage_to_duty_cycle_percentage(rdev, min_uV);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
146
147	ret = pwm_config(drvdata->pwm, (period / 100) * duty_cycle, period);
148	if (ret) {
149		dev_err(&rdev->dev, "Failed to configure PWM\n");
150		return ret;
151	}
152
153	ret = pwm_enable(drvdata->pwm);
154	if (ret) {
155		dev_err(&rdev->dev, "Failed to enable PWM\n");
156		return ret;
157	}
158	drvdata->volt_uV = min_uV;
159
160	/* Delay required by PWM regulator to settle to the new voltage */
161	usleep_range(ramp_delay, ramp_delay + 1000);
162
163	return 0;
164}
165
166static struct regulator_ops pwm_regulator_voltage_table_ops = {
167	.set_voltage_sel = pwm_regulator_set_voltage_sel,
168	.get_voltage_sel = pwm_regulator_get_voltage_sel,
169	.list_voltage    = pwm_regulator_list_voltage,
170	.map_voltage     = regulator_map_voltage_iterate,
171	.enable          = pwm_regulator_enable,
172	.disable         = pwm_regulator_disable,
173	.is_enabled      = pwm_regulator_is_enabled,
174};
175
176static struct regulator_ops pwm_regulator_voltage_continuous_ops = {
177	.get_voltage = pwm_regulator_get_voltage,
178	.set_voltage = pwm_regulator_set_voltage,
179	.enable          = pwm_regulator_enable,
180	.disable         = pwm_regulator_disable,
181	.is_enabled      = pwm_regulator_is_enabled,
182};
183
184static struct regulator_desc pwm_regulator_desc = {
185	.name		= "pwm-regulator",
186	.type		= REGULATOR_VOLTAGE,
187	.owner		= THIS_MODULE,
188	.supply_name    = "pwm",
189};
190
191static int pwm_regulator_init_table(struct platform_device *pdev,
192				    struct pwm_regulator_data *drvdata)
193{
194	struct device_node *np = pdev->dev.of_node;
195	struct pwm_voltages *duty_cycle_table;
196	unsigned int length = 0;
197	int ret;
198
199	of_find_property(np, "voltage-table", &length);
200
201	if ((length < sizeof(*duty_cycle_table)) ||
202	    (length % sizeof(*duty_cycle_table))) {
203		dev_err(&pdev->dev,
204			"voltage-table length(%d) is invalid\n",
205			length);
206		return -EINVAL;
207	}
208
209	duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL);
210	if (!duty_cycle_table)
211		return -ENOMEM;
212
213	ret = of_property_read_u32_array(np, "voltage-table",
214					 (u32 *)duty_cycle_table,
215					 length / sizeof(u32));
216	if (ret) {
217		dev_err(&pdev->dev, "Failed to read voltage-table\n");
218		return ret;
219	}
220
 
221	drvdata->duty_cycle_table	= duty_cycle_table;
222	memcpy(&drvdata->ops, &pwm_regulator_voltage_table_ops,
223	       sizeof(drvdata->ops));
224	drvdata->desc.ops = &drvdata->ops;
225	drvdata->desc.n_voltages	= length / sizeof(*duty_cycle_table);
226
227	return 0;
228}
229
230static int pwm_regulator_init_continuous(struct platform_device *pdev,
231					 struct pwm_regulator_data *drvdata)
232{
233	memcpy(&drvdata->ops, &pwm_regulator_voltage_continuous_ops,
234	       sizeof(drvdata->ops));
235	drvdata->desc.ops = &drvdata->ops;
 
236	drvdata->desc.continuous_voltage_range = true;
237
 
 
 
 
 
 
 
 
 
 
 
 
 
 
238	return 0;
239}
240
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
241static int pwm_regulator_probe(struct platform_device *pdev)
242{
243	const struct regulator_init_data *init_data;
244	struct pwm_regulator_data *drvdata;
245	struct regulator_dev *regulator;
246	struct regulator_config config = { };
247	struct device_node *np = pdev->dev.of_node;
 
248	int ret;
249
250	if (!np) {
251		dev_err(&pdev->dev, "Device Tree node missing\n");
252		return -EINVAL;
253	}
254
255	drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
256	if (!drvdata)
257		return -ENOMEM;
258
259	memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc));
260
261	if (of_find_property(np, "voltage-table", NULL))
262		ret = pwm_regulator_init_table(pdev, drvdata);
263	else
264		ret = pwm_regulator_init_continuous(pdev, drvdata);
265	if (ret)
266		return ret;
267
268	init_data = of_get_regulator_init_data(&pdev->dev, np,
269					       &drvdata->desc);
270	if (!init_data)
271		return -ENOMEM;
272
273	config.of_node = np;
274	config.dev = &pdev->dev;
275	config.driver_data = drvdata;
276	config.init_data = init_data;
277
278	drvdata->pwm = devm_pwm_get(&pdev->dev, NULL);
279	if (IS_ERR(drvdata->pwm)) {
280		dev_err(&pdev->dev, "Failed to get PWM\n");
281		return PTR_ERR(drvdata->pwm);
 
 
 
 
 
 
 
 
 
 
282	}
283
 
 
 
 
 
 
 
 
 
284	regulator = devm_regulator_register(&pdev->dev,
285					    &drvdata->desc, &config);
286	if (IS_ERR(regulator)) {
287		dev_err(&pdev->dev, "Failed to register regulator %s\n",
288			drvdata->desc.name);
289		return PTR_ERR(regulator);
 
290	}
291
292	return 0;
293}
294
295static const struct of_device_id pwm_of_match[] = {
296	{ .compatible = "pwm-regulator" },
297	{ },
298};
299MODULE_DEVICE_TABLE(of, pwm_of_match);
300
301static struct platform_driver pwm_regulator_driver = {
302	.driver = {
303		.name		= "pwm-regulator",
 
304		.of_match_table = of_match_ptr(pwm_of_match),
305	},
306	.probe = pwm_regulator_probe,
307};
308
309module_platform_driver(pwm_regulator_driver);
310
311MODULE_LICENSE("GPL");
312MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>");
313MODULE_DESCRIPTION("PWM Regulator Driver");
314MODULE_ALIAS("platform:pwm-regulator");