Commit | Line | Data |
---|---|---|
d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
aa66cc66 CZ |
2 | /* |
3 | * Regulator driver for PWM Regulators | |
4 | * | |
5 | * Copyright (C) 2014 - STMicroelectronics Inc. | |
6 | * | |
7 | * Author: Lee Jones <lee.jones@linaro.org> | |
aa66cc66 CZ |
8 | */ |
9 | ||
10 | #include <linux/module.h> | |
11 | #include <linux/init.h> | |
12 | #include <linux/err.h> | |
13 | #include <linux/regulator/driver.h> | |
14 | #include <linux/regulator/machine.h> | |
15 | #include <linux/regulator/of_regulator.h> | |
16 | #include <linux/of.h> | |
17 | #include <linux/of_device.h> | |
18 | #include <linux/pwm.h> | |
27bfa889 | 19 | #include <linux/gpio/consumer.h> |
aa66cc66 | 20 | |
ea398e28 BB |
21 | struct pwm_continuous_reg_data { |
22 | unsigned int min_uV_dutycycle; | |
23 | unsigned int max_uV_dutycycle; | |
24 | unsigned int dutycycle_unit; | |
25 | }; | |
26 | ||
aa66cc66 | 27 | struct pwm_regulator_data { |
4773be18 | 28 | /* Shared */ |
aa66cc66 | 29 | struct pwm_device *pwm; |
4773be18 LJ |
30 | |
31 | /* Voltage table */ | |
32 | struct pwm_voltages *duty_cycle_table; | |
f907a0a9 | 33 | |
ea398e28 BB |
34 | /* Continuous mode info */ |
35 | struct pwm_continuous_reg_data continuous; | |
36 | ||
f907a0a9 LD |
37 | /* regulator descriptor */ |
38 | struct regulator_desc desc; | |
39 | ||
aa66cc66 | 40 | int state; |
4773be18 | 41 | |
27bfa889 AC |
42 | /* Enable GPIO */ |
43 | struct gpio_desc *enb_gpio; | |
aa66cc66 CZ |
44 | }; |
45 | ||
46 | struct pwm_voltages { | |
47 | unsigned int uV; | |
48 | unsigned int dutycycle; | |
49 | }; | |
50 | ||
4773be18 LJ |
51 | /** |
52 | * Voltage table call-backs | |
53 | */ | |
87248991 BB |
54 | static 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 | ||
ab101e35 | 72 | static int pwm_regulator_get_voltage_sel(struct regulator_dev *rdev) |
aa66cc66 | 73 | { |
ab101e35 | 74 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); |
aa66cc66 | 75 | |
87248991 BB |
76 | if (drvdata->state < 0) |
77 | pwm_regulator_init_state(rdev); | |
78 | ||
aa66cc66 CZ |
79 | return drvdata->state; |
80 | } | |
81 | ||
ab101e35 | 82 | static int pwm_regulator_set_voltage_sel(struct regulator_dev *rdev, |
aa66cc66 CZ |
83 | unsigned selector) |
84 | { | |
ab101e35 | 85 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); |
3f4eb39b | 86 | struct pwm_state pstate; |
aa66cc66 CZ |
87 | int ret; |
88 | ||
3f4eb39b BB |
89 | pwm_init_state(drvdata->pwm, &pstate); |
90 | pwm_set_relative_duty_cycle(&pstate, | |
91 | drvdata->duty_cycle_table[selector].dutycycle, 100); | |
aa66cc66 | 92 | |
3f4eb39b | 93 | ret = pwm_apply_state(drvdata->pwm, &pstate); |
aa66cc66 | 94 | if (ret) { |
5bf59bd5 | 95 | dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret); |
aa66cc66 CZ |
96 | return ret; |
97 | } | |
98 | ||
99 | drvdata->state = selector; | |
100 | ||
aa66cc66 CZ |
101 | return 0; |
102 | } | |
103 | ||
ab101e35 | 104 | static int pwm_regulator_list_voltage(struct regulator_dev *rdev, |
aa66cc66 CZ |
105 | unsigned selector) |
106 | { | |
ab101e35 | 107 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); |
aa66cc66 | 108 | |
ab101e35 | 109 | if (selector >= rdev->desc->n_voltages) |
aa66cc66 CZ |
110 | return -EINVAL; |
111 | ||
112 | return drvdata->duty_cycle_table[selector].uV; | |
113 | } | |
4773be18 | 114 | |
1de7d802 BB |
115 | static int pwm_regulator_enable(struct regulator_dev *dev) |
116 | { | |
117 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev); | |
118 | ||
a4aae5af | 119 | gpiod_set_value_cansleep(drvdata->enb_gpio, 1); |
27bfa889 | 120 | |
1de7d802 BB |
121 | return pwm_enable(drvdata->pwm); |
122 | } | |
123 | ||
124 | static 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 | ||
a4aae5af | 130 | gpiod_set_value_cansleep(drvdata->enb_gpio, 0); |
27bfa889 | 131 | |
1de7d802 BB |
132 | return 0; |
133 | } | |
134 | ||
135 | static int pwm_regulator_is_enabled(struct regulator_dev *dev) | |
136 | { | |
137 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(dev); | |
138 | ||
27bfa889 AC |
139 | if (drvdata->enb_gpio && !gpiod_get_value_cansleep(drvdata->enb_gpio)) |
140 | return false; | |
141 | ||
1de7d802 BB |
142 | return pwm_is_enabled(drvdata->pwm); |
143 | } | |
144 | ||
4773be18 LJ |
145 | static int pwm_regulator_get_voltage(struct regulator_dev *rdev) |
146 | { | |
147 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); | |
ea398e28 BB |
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; | |
d9070fdb | 151 | int min_uV = rdev->constraints->min_uV; |
ea398e28 BB |
152 | int max_uV = rdev->constraints->max_uV; |
153 | int diff_uV = max_uV - min_uV; | |
d9070fdb | 154 | struct pwm_state pstate; |
ea398e28 BB |
155 | unsigned int diff_duty; |
156 | unsigned int voltage; | |
4773be18 | 157 | |
d9070fdb BB |
158 | pwm_get_state(drvdata->pwm, &pstate); |
159 | ||
ea398e28 BB |
160 | voltage = pwm_get_relative_duty_cycle(&pstate, duty_unit); |
161 | ||
162 | /* | |
163 | * The dutycycle for min_uV might be greater than the one for max_uV. | |
164 | * This is happening when the user needs an inversed polarity, but the | |
165 | * PWM device does not support inversing it in hardware. | |
166 | */ | |
167 | if (max_uV_duty < min_uV_duty) { | |
168 | voltage = min_uV_duty - voltage; | |
169 | diff_duty = min_uV_duty - max_uV_duty; | |
170 | } else { | |
171 | voltage = voltage - min_uV_duty; | |
172 | diff_duty = max_uV_duty - min_uV_duty; | |
173 | } | |
174 | ||
175 | voltage = DIV_ROUND_CLOSEST_ULL((u64)voltage * diff_uV, diff_duty); | |
176 | ||
177 | return voltage + min_uV; | |
4773be18 LJ |
178 | } |
179 | ||
180 | static int pwm_regulator_set_voltage(struct regulator_dev *rdev, | |
ea398e28 BB |
181 | int req_min_uV, int req_max_uV, |
182 | unsigned int *selector) | |
4773be18 LJ |
183 | { |
184 | struct pwm_regulator_data *drvdata = rdev_get_drvdata(rdev); | |
ea398e28 BB |
185 | unsigned int min_uV_duty = drvdata->continuous.min_uV_dutycycle; |
186 | unsigned int max_uV_duty = drvdata->continuous.max_uV_dutycycle; | |
187 | unsigned int duty_unit = drvdata->continuous.dutycycle_unit; | |
ea398e28 BB |
188 | int min_uV = rdev->constraints->min_uV; |
189 | int max_uV = rdev->constraints->max_uV; | |
190 | int diff_uV = max_uV - min_uV; | |
3f4eb39b | 191 | struct pwm_state pstate; |
ea398e28 BB |
192 | unsigned int diff_duty; |
193 | unsigned int dutycycle; | |
4773be18 LJ |
194 | int ret; |
195 | ||
3f4eb39b | 196 | pwm_init_state(drvdata->pwm, &pstate); |
fd786fb0 | 197 | |
ea398e28 BB |
198 | /* |
199 | * The dutycycle for min_uV might be greater than the one for max_uV. | |
200 | * This is happening when the user needs an inversed polarity, but the | |
201 | * PWM device does not support inversing it in hardware. | |
202 | */ | |
203 | if (max_uV_duty < min_uV_duty) | |
204 | diff_duty = min_uV_duty - max_uV_duty; | |
205 | else | |
206 | diff_duty = max_uV_duty - min_uV_duty; | |
207 | ||
208 | dutycycle = DIV_ROUND_CLOSEST_ULL((u64)(req_min_uV - min_uV) * | |
209 | diff_duty, | |
210 | diff_uV); | |
211 | ||
212 | if (max_uV_duty < min_uV_duty) | |
213 | dutycycle = min_uV_duty - dutycycle; | |
214 | else | |
215 | dutycycle = min_uV_duty + dutycycle; | |
216 | ||
217 | pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit); | |
4773be18 | 218 | |
3f4eb39b | 219 | ret = pwm_apply_state(drvdata->pwm, &pstate); |
4773be18 | 220 | if (ret) { |
5bf59bd5 | 221 | dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret); |
4773be18 LJ |
222 | return ret; |
223 | } | |
224 | ||
4773be18 LJ |
225 | return 0; |
226 | } | |
227 | ||
638aef7a | 228 | static const struct regulator_ops pwm_regulator_voltage_table_ops = { |
aa66cc66 CZ |
229 | .set_voltage_sel = pwm_regulator_set_voltage_sel, |
230 | .get_voltage_sel = pwm_regulator_get_voltage_sel, | |
231 | .list_voltage = pwm_regulator_list_voltage, | |
232 | .map_voltage = regulator_map_voltage_iterate, | |
1de7d802 BB |
233 | .enable = pwm_regulator_enable, |
234 | .disable = pwm_regulator_disable, | |
235 | .is_enabled = pwm_regulator_is_enabled, | |
aa66cc66 CZ |
236 | }; |
237 | ||
638aef7a | 238 | static const struct regulator_ops pwm_regulator_voltage_continuous_ops = { |
4773be18 LJ |
239 | .get_voltage = pwm_regulator_get_voltage, |
240 | .set_voltage = pwm_regulator_set_voltage, | |
1de7d802 BB |
241 | .enable = pwm_regulator_enable, |
242 | .disable = pwm_regulator_disable, | |
243 | .is_enabled = pwm_regulator_is_enabled, | |
4773be18 LJ |
244 | }; |
245 | ||
638aef7a | 246 | static const struct regulator_desc pwm_regulator_desc = { |
aa66cc66 | 247 | .name = "pwm-regulator", |
aa66cc66 CZ |
248 | .type = REGULATOR_VOLTAGE, |
249 | .owner = THIS_MODULE, | |
250 | .supply_name = "pwm", | |
251 | }; | |
252 | ||
f9178dad LJ |
253 | static int pwm_regulator_init_table(struct platform_device *pdev, |
254 | struct pwm_regulator_data *drvdata) | |
255 | { | |
256 | struct device_node *np = pdev->dev.of_node; | |
257 | struct pwm_voltages *duty_cycle_table; | |
60cb65eb | 258 | unsigned int length = 0; |
f9178dad LJ |
259 | int ret; |
260 | ||
261 | of_find_property(np, "voltage-table", &length); | |
262 | ||
263 | if ((length < sizeof(*duty_cycle_table)) || | |
264 | (length % sizeof(*duty_cycle_table))) { | |
5bf59bd5 | 265 | dev_err(&pdev->dev, "voltage-table length(%d) is invalid\n", |
f9178dad LJ |
266 | length); |
267 | return -EINVAL; | |
268 | } | |
269 | ||
270 | duty_cycle_table = devm_kzalloc(&pdev->dev, length, GFP_KERNEL); | |
271 | if (!duty_cycle_table) | |
272 | return -ENOMEM; | |
273 | ||
274 | ret = of_property_read_u32_array(np, "voltage-table", | |
275 | (u32 *)duty_cycle_table, | |
276 | length / sizeof(u32)); | |
277 | if (ret) { | |
5bf59bd5 | 278 | dev_err(&pdev->dev, "Failed to read voltage-table: %d\n", ret); |
f9178dad LJ |
279 | return ret; |
280 | } | |
281 | ||
87248991 | 282 | drvdata->state = -EINVAL; |
f9178dad | 283 | drvdata->duty_cycle_table = duty_cycle_table; |
638aef7a | 284 | drvdata->desc.ops = &pwm_regulator_voltage_table_ops; |
f907a0a9 | 285 | drvdata->desc.n_voltages = length / sizeof(*duty_cycle_table); |
f9178dad LJ |
286 | |
287 | return 0; | |
288 | } | |
289 | ||
4773be18 LJ |
290 | static int pwm_regulator_init_continuous(struct platform_device *pdev, |
291 | struct pwm_regulator_data *drvdata) | |
292 | { | |
ea398e28 BB |
293 | u32 dutycycle_range[2] = { 0, 100 }; |
294 | u32 dutycycle_unit = 100; | |
295 | ||
638aef7a | 296 | drvdata->desc.ops = &pwm_regulator_voltage_continuous_ops; |
f907a0a9 | 297 | drvdata->desc.continuous_voltage_range = true; |
4773be18 | 298 | |
ea398e28 BB |
299 | of_property_read_u32_array(pdev->dev.of_node, |
300 | "pwm-dutycycle-range", | |
301 | dutycycle_range, 2); | |
302 | of_property_read_u32(pdev->dev.of_node, "pwm-dutycycle-unit", | |
303 | &dutycycle_unit); | |
304 | ||
305 | if (dutycycle_range[0] > dutycycle_unit || | |
306 | dutycycle_range[1] > dutycycle_unit) | |
307 | return -EINVAL; | |
308 | ||
309 | drvdata->continuous.dutycycle_unit = dutycycle_unit; | |
310 | drvdata->continuous.min_uV_dutycycle = dutycycle_range[0]; | |
311 | drvdata->continuous.max_uV_dutycycle = dutycycle_range[1]; | |
312 | ||
4773be18 LJ |
313 | return 0; |
314 | } | |
315 | ||
aa66cc66 CZ |
316 | static int pwm_regulator_probe(struct platform_device *pdev) |
317 | { | |
5ad2cb14 | 318 | const struct regulator_init_data *init_data; |
aa66cc66 | 319 | struct pwm_regulator_data *drvdata; |
aa66cc66 CZ |
320 | struct regulator_dev *regulator; |
321 | struct regulator_config config = { }; | |
322 | struct device_node *np = pdev->dev.of_node; | |
27bfa889 | 323 | enum gpiod_flags gpio_flags; |
f9178dad | 324 | int ret; |
aa66cc66 CZ |
325 | |
326 | if (!np) { | |
327 | dev_err(&pdev->dev, "Device Tree node missing\n"); | |
328 | return -EINVAL; | |
329 | } | |
330 | ||
331 | drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL); | |
332 | if (!drvdata) | |
333 | return -ENOMEM; | |
334 | ||
f907a0a9 LD |
335 | memcpy(&drvdata->desc, &pwm_regulator_desc, sizeof(drvdata->desc)); |
336 | ||
4773be18 | 337 | if (of_find_property(np, "voltage-table", NULL)) |
f9178dad | 338 | ret = pwm_regulator_init_table(pdev, drvdata); |
4773be18 LJ |
339 | else |
340 | ret = pwm_regulator_init_continuous(pdev, drvdata); | |
341 | if (ret) | |
342 | return ret; | |
aa66cc66 | 343 | |
5ad2cb14 | 344 | init_data = of_get_regulator_init_data(&pdev->dev, np, |
f907a0a9 | 345 | &drvdata->desc); |
5ad2cb14 | 346 | if (!init_data) |
aa66cc66 CZ |
347 | return -ENOMEM; |
348 | ||
349 | config.of_node = np; | |
350 | config.dev = &pdev->dev; | |
351 | config.driver_data = drvdata; | |
5ad2cb14 | 352 | config.init_data = init_data; |
aa66cc66 CZ |
353 | |
354 | drvdata->pwm = devm_pwm_get(&pdev->dev, NULL); | |
355 | if (IS_ERR(drvdata->pwm)) { | |
5bf59bd5 | 356 | ret = PTR_ERR(drvdata->pwm); |
0cd71b9a JH |
357 | if (ret == -EPROBE_DEFER) |
358 | dev_dbg(&pdev->dev, | |
359 | "Failed to get PWM, deferring probe\n"); | |
360 | else | |
361 | dev_err(&pdev->dev, "Failed to get PWM: %d\n", ret); | |
5bf59bd5 | 362 | return ret; |
aa66cc66 CZ |
363 | } |
364 | ||
27bfa889 AC |
365 | if (init_data->constraints.boot_on || init_data->constraints.always_on) |
366 | gpio_flags = GPIOD_OUT_HIGH; | |
367 | else | |
368 | gpio_flags = GPIOD_OUT_LOW; | |
369 | drvdata->enb_gpio = devm_gpiod_get_optional(&pdev->dev, "enable", | |
370 | gpio_flags); | |
371 | if (IS_ERR(drvdata->enb_gpio)) { | |
372 | ret = PTR_ERR(drvdata->enb_gpio); | |
373 | dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", ret); | |
374 | return ret; | |
375 | } | |
376 | ||
fd4f99c4 BB |
377 | ret = pwm_adjust_config(drvdata->pwm); |
378 | if (ret) | |
379 | return ret; | |
8c12ad8e | 380 | |
aa66cc66 | 381 | regulator = devm_regulator_register(&pdev->dev, |
f907a0a9 | 382 | &drvdata->desc, &config); |
aa66cc66 | 383 | if (IS_ERR(regulator)) { |
5bf59bd5 LD |
384 | ret = PTR_ERR(regulator); |
385 | dev_err(&pdev->dev, "Failed to register regulator %s: %d\n", | |
386 | drvdata->desc.name, ret); | |
387 | return ret; | |
aa66cc66 CZ |
388 | } |
389 | ||
390 | return 0; | |
391 | } | |
392 | ||
393 | static const struct of_device_id pwm_of_match[] = { | |
394 | { .compatible = "pwm-regulator" }, | |
395 | { }, | |
396 | }; | |
397 | MODULE_DEVICE_TABLE(of, pwm_of_match); | |
398 | ||
399 | static struct platform_driver pwm_regulator_driver = { | |
400 | .driver = { | |
401 | .name = "pwm-regulator", | |
aa66cc66 CZ |
402 | .of_match_table = of_match_ptr(pwm_of_match), |
403 | }, | |
404 | .probe = pwm_regulator_probe, | |
405 | }; | |
406 | ||
407 | module_platform_driver(pwm_regulator_driver); | |
408 | ||
409 | MODULE_LICENSE("GPL"); | |
410 | MODULE_AUTHOR("Lee Jones <lee.jones@linaro.org>"); | |
411 | MODULE_DESCRIPTION("PWM Regulator Driver"); | |
412 | MODULE_ALIAS("platform:pwm-regulator"); |