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 */ |
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) |
90 | { | |
ab101e35 | 91 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); |
3f4eb39b | 92 | struct pwm_state pstate; |
aa66cc66 CZ |
93 | int ret; |
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) |
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; |
159 | int diff_uV = max_uV - min_uV; | |
d9070fdb | 160 | struct pwm_state pstate; |
ea398e28 BB |
161 | unsigned int diff_duty; |
162 | unsigned int voltage; | |
4773be18 | 163 | |
d9070fdb BB |
164 | pwm_get_state(drvdata->pwm, &pstate); |
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, |
188 | unsigned int *selector) | |
4773be18 LJ |
189 | { |
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; |
199 | unsigned int dutycycle; | |
4773be18 LJ |
200 | int ret; |
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 | }; |
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 | }; |
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) |
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)); |
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 | } |
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"); |