Commit | Line | Data |
---|---|---|
c82ee6d3 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
0c2498f1 SH |
2 | /* |
3 | * Generic pwmlib implementation | |
4 | * | |
5 | * Copyright (C) 2011 Sascha Hauer <s.hauer@pengutronix.de> | |
f051c466 | 6 | * Copyright (C) 2011-2012 Avionic Design GmbH |
0c2498f1 SH |
7 | */ |
8 | ||
4a6ef8e3 | 9 | #include <linux/acpi.h> |
0c2498f1 SH |
10 | #include <linux/module.h> |
11 | #include <linux/pwm.h> | |
f051c466 | 12 | #include <linux/radix-tree.h> |
0c2498f1 SH |
13 | #include <linux/list.h> |
14 | #include <linux/mutex.h> | |
15 | #include <linux/err.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/device.h> | |
62099abf TR |
18 | #include <linux/debugfs.h> |
19 | #include <linux/seq_file.h> | |
0c2498f1 | 20 | |
208be769 | 21 | #include <dt-bindings/pwm/pwm.h> |
0c2498f1 | 22 | |
208be769 | 23 | #define MAX_PWMS 1024 |
83af2402 | 24 | |
8138d2dd TR |
25 | static DEFINE_MUTEX(pwm_lookup_lock); |
26 | static LIST_HEAD(pwm_lookup_list); | |
0c2498f1 | 27 | static DEFINE_MUTEX(pwm_lock); |
f051c466 TR |
28 | static LIST_HEAD(pwm_chips); |
29 | static DECLARE_BITMAP(allocated_pwms, MAX_PWMS); | |
30 | static RADIX_TREE(pwm_tree, GFP_KERNEL); | |
0c2498f1 | 31 | |
f051c466 | 32 | static struct pwm_device *pwm_to_device(unsigned int pwm) |
0c2498f1 | 33 | { |
f051c466 TR |
34 | return radix_tree_lookup(&pwm_tree, pwm); |
35 | } | |
36 | ||
37 | static int alloc_pwms(int pwm, unsigned int count) | |
38 | { | |
39 | unsigned int from = 0; | |
40 | unsigned int start; | |
41 | ||
42 | if (pwm >= MAX_PWMS) | |
43 | return -EINVAL; | |
44 | ||
45 | if (pwm >= 0) | |
46 | from = pwm; | |
0c2498f1 | 47 | |
f051c466 TR |
48 | start = bitmap_find_next_zero_area(allocated_pwms, MAX_PWMS, from, |
49 | count, 0); | |
50 | ||
51 | if (pwm >= 0 && start != pwm) | |
52 | return -EEXIST; | |
53 | ||
54 | if (start + count > MAX_PWMS) | |
55 | return -ENOSPC; | |
56 | ||
57 | return start; | |
58 | } | |
59 | ||
60 | static void free_pwms(struct pwm_chip *chip) | |
61 | { | |
62 | unsigned int i; | |
63 | ||
64 | for (i = 0; i < chip->npwm; i++) { | |
65 | struct pwm_device *pwm = &chip->pwms[i]; | |
83a98864 | 66 | |
f051c466 | 67 | radix_tree_delete(&pwm_tree, pwm->pwm); |
0c2498f1 SH |
68 | } |
69 | ||
f051c466 TR |
70 | bitmap_clear(allocated_pwms, chip->base, chip->npwm); |
71 | ||
72 | kfree(chip->pwms); | |
73 | chip->pwms = NULL; | |
74 | } | |
75 | ||
8138d2dd TR |
76 | static struct pwm_chip *pwmchip_find_by_name(const char *name) |
77 | { | |
78 | struct pwm_chip *chip; | |
79 | ||
80 | if (!name) | |
81 | return NULL; | |
82 | ||
83 | mutex_lock(&pwm_lock); | |
84 | ||
85 | list_for_each_entry(chip, &pwm_chips, list) { | |
86 | const char *chip_name = dev_name(chip->dev); | |
87 | ||
88 | if (chip_name && strcmp(chip_name, name) == 0) { | |
89 | mutex_unlock(&pwm_lock); | |
90 | return chip; | |
91 | } | |
92 | } | |
93 | ||
94 | mutex_unlock(&pwm_lock); | |
95 | ||
96 | return NULL; | |
97 | } | |
98 | ||
f051c466 TR |
99 | static int pwm_device_request(struct pwm_device *pwm, const char *label) |
100 | { | |
101 | int err; | |
102 | ||
103 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) | |
104 | return -EBUSY; | |
105 | ||
106 | if (!try_module_get(pwm->chip->ops->owner)) | |
107 | return -ENODEV; | |
108 | ||
109 | if (pwm->chip->ops->request) { | |
110 | err = pwm->chip->ops->request(pwm->chip, pwm); | |
111 | if (err) { | |
112 | module_put(pwm->chip->ops->owner); | |
113 | return err; | |
114 | } | |
115 | } | |
116 | ||
117 | set_bit(PWMF_REQUESTED, &pwm->flags); | |
118 | pwm->label = label; | |
119 | ||
120 | return 0; | |
121 | } | |
122 | ||
83af2402 PA |
123 | struct pwm_device * |
124 | of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) | |
125 | { | |
126 | struct pwm_device *pwm; | |
127 | ||
42883cbc | 128 | /* check, whether the driver supports a third cell for flags */ |
83af2402 PA |
129 | if (pc->of_pwm_n_cells < 3) |
130 | return ERR_PTR(-EINVAL); | |
131 | ||
42883cbc LW |
132 | /* flags in the third cell are optional */ |
133 | if (args->args_count < 2) | |
134 | return ERR_PTR(-EINVAL); | |
135 | ||
83af2402 PA |
136 | if (args->args[0] >= pc->npwm) |
137 | return ERR_PTR(-EINVAL); | |
138 | ||
139 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); | |
140 | if (IS_ERR(pwm)) | |
141 | return pwm; | |
142 | ||
e39c0df1 | 143 | pwm->args.period = args->args[1]; |
42883cbc | 144 | pwm->args.polarity = PWM_POLARITY_NORMAL; |
83af2402 | 145 | |
42883cbc | 146 | if (args->args_count > 2 && args->args[2] & PWM_POLARITY_INVERTED) |
e39c0df1 | 147 | pwm->args.polarity = PWM_POLARITY_INVERSED; |
83af2402 PA |
148 | |
149 | return pwm; | |
150 | } | |
417328c3 | 151 | EXPORT_SYMBOL_GPL(of_pwm_xlate_with_flags); |
83af2402 | 152 | |
e50d3523 SK |
153 | static struct pwm_device * |
154 | of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args) | |
7299ab70 TR |
155 | { |
156 | struct pwm_device *pwm; | |
157 | ||
42883cbc | 158 | /* sanity check driver support */ |
7299ab70 TR |
159 | if (pc->of_pwm_n_cells < 2) |
160 | return ERR_PTR(-EINVAL); | |
161 | ||
42883cbc LW |
162 | /* all cells are required */ |
163 | if (args->args_count != pc->of_pwm_n_cells) | |
164 | return ERR_PTR(-EINVAL); | |
165 | ||
7299ab70 TR |
166 | if (args->args[0] >= pc->npwm) |
167 | return ERR_PTR(-EINVAL); | |
168 | ||
169 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); | |
170 | if (IS_ERR(pwm)) | |
171 | return pwm; | |
172 | ||
e39c0df1 | 173 | pwm->args.period = args->args[1]; |
7299ab70 TR |
174 | |
175 | return pwm; | |
176 | } | |
177 | ||
dfeb86ec | 178 | static void of_pwmchip_add(struct pwm_chip *chip) |
7299ab70 TR |
179 | { |
180 | if (!chip->dev || !chip->dev->of_node) | |
181 | return; | |
182 | ||
183 | if (!chip->of_xlate) { | |
184 | chip->of_xlate = of_pwm_simple_xlate; | |
185 | chip->of_pwm_n_cells = 2; | |
186 | } | |
187 | ||
188 | of_node_get(chip->dev->of_node); | |
189 | } | |
190 | ||
dfeb86ec | 191 | static void of_pwmchip_remove(struct pwm_chip *chip) |
7299ab70 | 192 | { |
8d6cc073 | 193 | if (chip->dev) |
7299ab70 TR |
194 | of_node_put(chip->dev->of_node); |
195 | } | |
196 | ||
f051c466 TR |
197 | /** |
198 | * pwm_set_chip_data() - set private chip data for a PWM | |
199 | * @pwm: PWM device | |
200 | * @data: pointer to chip-specific data | |
04883802 TR |
201 | * |
202 | * Returns: 0 on success or a negative error code on failure. | |
f051c466 TR |
203 | */ |
204 | int pwm_set_chip_data(struct pwm_device *pwm, void *data) | |
205 | { | |
206 | if (!pwm) | |
207 | return -EINVAL; | |
208 | ||
209 | pwm->chip_data = data; | |
210 | ||
211 | return 0; | |
212 | } | |
928c4477 | 213 | EXPORT_SYMBOL_GPL(pwm_set_chip_data); |
f051c466 TR |
214 | |
215 | /** | |
216 | * pwm_get_chip_data() - get private chip data for a PWM | |
217 | * @pwm: PWM device | |
04883802 TR |
218 | * |
219 | * Returns: A pointer to the chip-private data for the PWM device. | |
f051c466 TR |
220 | */ |
221 | void *pwm_get_chip_data(struct pwm_device *pwm) | |
222 | { | |
223 | return pwm ? pwm->chip_data : NULL; | |
0c2498f1 | 224 | } |
928c4477 | 225 | EXPORT_SYMBOL_GPL(pwm_get_chip_data); |
0c2498f1 | 226 | |
5ec803ed BB |
227 | static bool pwm_ops_check(const struct pwm_ops *ops) |
228 | { | |
229 | /* driver supports legacy, non-atomic operation */ | |
230 | if (ops->config && ops->enable && ops->disable) | |
231 | return true; | |
232 | ||
233 | /* driver supports atomic operation */ | |
234 | if (ops->apply) | |
235 | return true; | |
236 | ||
237 | return false; | |
238 | } | |
239 | ||
0c2498f1 | 240 | /** |
b6a00fae | 241 | * pwmchip_add_with_polarity() - register a new PWM chip |
0c2498f1 | 242 | * @chip: the PWM chip to add |
b6a00fae | 243 | * @polarity: initial polarity of PWM channels |
f051c466 TR |
244 | * |
245 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base | |
b6a00fae TK |
246 | * will be used. The initial polarity for all channels is specified by the |
247 | * @polarity parameter. | |
04883802 TR |
248 | * |
249 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 | 250 | */ |
b6a00fae TK |
251 | int pwmchip_add_with_polarity(struct pwm_chip *chip, |
252 | enum pwm_polarity polarity) | |
0c2498f1 SH |
253 | { |
254 | struct pwm_device *pwm; | |
f051c466 TR |
255 | unsigned int i; |
256 | int ret; | |
0c2498f1 | 257 | |
5ec803ed BB |
258 | if (!chip || !chip->dev || !chip->ops || !chip->npwm) |
259 | return -EINVAL; | |
260 | ||
261 | if (!pwm_ops_check(chip->ops)) | |
f051c466 | 262 | return -EINVAL; |
0c2498f1 SH |
263 | |
264 | mutex_lock(&pwm_lock); | |
265 | ||
f051c466 TR |
266 | ret = alloc_pwms(chip->base, chip->npwm); |
267 | if (ret < 0) | |
268 | goto out; | |
269 | ||
2907f8ab | 270 | chip->pwms = kcalloc(chip->npwm, sizeof(*pwm), GFP_KERNEL); |
f051c466 TR |
271 | if (!chip->pwms) { |
272 | ret = -ENOMEM; | |
0c2498f1 SH |
273 | goto out; |
274 | } | |
275 | ||
f051c466 TR |
276 | chip->base = ret; |
277 | ||
278 | for (i = 0; i < chip->npwm; i++) { | |
279 | pwm = &chip->pwms[i]; | |
280 | ||
281 | pwm->chip = chip; | |
282 | pwm->pwm = chip->base + i; | |
283 | pwm->hwpwm = i; | |
43a276b0 | 284 | pwm->state.polarity = polarity; |
0c2498f1 | 285 | |
15fa8a43 BB |
286 | if (chip->ops->get_state) |
287 | chip->ops->get_state(chip, pwm, &pwm->state); | |
0c2498f1 | 288 | |
f051c466 TR |
289 | radix_tree_insert(&pwm_tree, pwm->pwm, pwm); |
290 | } | |
291 | ||
292 | bitmap_set(allocated_pwms, chip->base, chip->npwm); | |
293 | ||
294 | INIT_LIST_HEAD(&chip->list); | |
295 | list_add(&chip->list, &pwm_chips); | |
0c2498f1 | 296 | |
f051c466 TR |
297 | ret = 0; |
298 | ||
7299ab70 TR |
299 | if (IS_ENABLED(CONFIG_OF)) |
300 | of_pwmchip_add(chip); | |
301 | ||
f051c466 TR |
302 | out: |
303 | mutex_unlock(&pwm_lock); | |
347ab948 PH |
304 | |
305 | if (!ret) | |
306 | pwmchip_sysfs_export(chip); | |
307 | ||
0c2498f1 SH |
308 | return ret; |
309 | } | |
b6a00fae TK |
310 | EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity); |
311 | ||
312 | /** | |
313 | * pwmchip_add() - register a new PWM chip | |
314 | * @chip: the PWM chip to add | |
315 | * | |
316 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base | |
317 | * will be used. The initial polarity for all channels is normal. | |
04883802 TR |
318 | * |
319 | * Returns: 0 on success or a negative error code on failure. | |
b6a00fae TK |
320 | */ |
321 | int pwmchip_add(struct pwm_chip *chip) | |
322 | { | |
323 | return pwmchip_add_with_polarity(chip, PWM_POLARITY_NORMAL); | |
324 | } | |
0c2498f1 SH |
325 | EXPORT_SYMBOL_GPL(pwmchip_add); |
326 | ||
327 | /** | |
328 | * pwmchip_remove() - remove a PWM chip | |
329 | * @chip: the PWM chip to remove | |
330 | * | |
331 | * Removes a PWM chip. This function may return busy if the PWM chip provides | |
332 | * a PWM device that is still requested. | |
04883802 TR |
333 | * |
334 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 SH |
335 | */ |
336 | int pwmchip_remove(struct pwm_chip *chip) | |
337 | { | |
f051c466 | 338 | unsigned int i; |
0c2498f1 SH |
339 | int ret = 0; |
340 | ||
347ab948 | 341 | pwmchip_sysfs_unexport(chip); |
0733424c | 342 | |
0c2498f1 SH |
343 | mutex_lock(&pwm_lock); |
344 | ||
f051c466 TR |
345 | for (i = 0; i < chip->npwm; i++) { |
346 | struct pwm_device *pwm = &chip->pwms[i]; | |
0c2498f1 | 347 | |
f051c466 TR |
348 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) { |
349 | ret = -EBUSY; | |
350 | goto out; | |
351 | } | |
0c2498f1 SH |
352 | } |
353 | ||
f051c466 | 354 | list_del_init(&chip->list); |
7299ab70 TR |
355 | |
356 | if (IS_ENABLED(CONFIG_OF)) | |
357 | of_pwmchip_remove(chip); | |
358 | ||
f051c466 | 359 | free_pwms(chip); |
0c2498f1 | 360 | |
0c2498f1 SH |
361 | out: |
362 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
363 | return ret; |
364 | } | |
365 | EXPORT_SYMBOL_GPL(pwmchip_remove); | |
366 | ||
367 | /** | |
368 | * pwm_request() - request a PWM device | |
04883802 | 369 | * @pwm: global PWM device index |
0c2498f1 | 370 | * @label: PWM device label |
8138d2dd TR |
371 | * |
372 | * This function is deprecated, use pwm_get() instead. | |
04883802 TR |
373 | * |
374 | * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on | |
375 | * failure. | |
0c2498f1 | 376 | */ |
f051c466 | 377 | struct pwm_device *pwm_request(int pwm, const char *label) |
0c2498f1 | 378 | { |
f051c466 TR |
379 | struct pwm_device *dev; |
380 | int err; | |
381 | ||
382 | if (pwm < 0 || pwm >= MAX_PWMS) | |
383 | return ERR_PTR(-EINVAL); | |
0c2498f1 SH |
384 | |
385 | mutex_lock(&pwm_lock); | |
386 | ||
f051c466 TR |
387 | dev = pwm_to_device(pwm); |
388 | if (!dev) { | |
389 | dev = ERR_PTR(-EPROBE_DEFER); | |
0c2498f1 SH |
390 | goto out; |
391 | } | |
392 | ||
f051c466 TR |
393 | err = pwm_device_request(dev, label); |
394 | if (err < 0) | |
395 | dev = ERR_PTR(err); | |
0c2498f1 | 396 | |
f051c466 TR |
397 | out: |
398 | mutex_unlock(&pwm_lock); | |
0c2498f1 | 399 | |
f051c466 TR |
400 | return dev; |
401 | } | |
402 | EXPORT_SYMBOL_GPL(pwm_request); | |
0c2498f1 | 403 | |
f051c466 TR |
404 | /** |
405 | * pwm_request_from_chip() - request a PWM device relative to a PWM chip | |
406 | * @chip: PWM chip | |
407 | * @index: per-chip index of the PWM to request | |
408 | * @label: a literal description string of this PWM | |
409 | * | |
04883802 TR |
410 | * Returns: A pointer to the PWM device at the given index of the given PWM |
411 | * chip. A negative error code is returned if the index is not valid for the | |
412 | * specified PWM chip or if the PWM device cannot be requested. | |
f051c466 TR |
413 | */ |
414 | struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, | |
415 | unsigned int index, | |
416 | const char *label) | |
417 | { | |
418 | struct pwm_device *pwm; | |
419 | int err; | |
0c2498f1 | 420 | |
f051c466 TR |
421 | if (!chip || index >= chip->npwm) |
422 | return ERR_PTR(-EINVAL); | |
0c2498f1 | 423 | |
f051c466 TR |
424 | mutex_lock(&pwm_lock); |
425 | pwm = &chip->pwms[index]; | |
0c2498f1 | 426 | |
f051c466 TR |
427 | err = pwm_device_request(pwm, label); |
428 | if (err < 0) | |
429 | pwm = ERR_PTR(err); | |
430 | ||
431 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
432 | return pwm; |
433 | } | |
f051c466 | 434 | EXPORT_SYMBOL_GPL(pwm_request_from_chip); |
0c2498f1 SH |
435 | |
436 | /** | |
437 | * pwm_free() - free a PWM device | |
438 | * @pwm: PWM device | |
8138d2dd TR |
439 | * |
440 | * This function is deprecated, use pwm_put() instead. | |
0c2498f1 SH |
441 | */ |
442 | void pwm_free(struct pwm_device *pwm) | |
443 | { | |
8138d2dd | 444 | pwm_put(pwm); |
0c2498f1 SH |
445 | } |
446 | EXPORT_SYMBOL_GPL(pwm_free); | |
447 | ||
448 | /** | |
5ec803ed | 449 | * pwm_apply_state() - atomically apply a new state to a PWM device |
0c2498f1 | 450 | * @pwm: PWM device |
5ec803ed BB |
451 | * @state: new state to apply. This can be adjusted by the PWM driver |
452 | * if the requested config is not achievable, for example, | |
453 | * ->duty_cycle and ->period might be approximated. | |
0c2498f1 | 454 | */ |
5ec803ed | 455 | int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state) |
0c2498f1 | 456 | { |
76abbdde HS |
457 | int err; |
458 | ||
ef2bf499 BN |
459 | if (!pwm || !state || !state->period || |
460 | state->duty_cycle > state->period) | |
f051c466 TR |
461 | return -EINVAL; |
462 | ||
309b32fb UKK |
463 | if (state->period == pwm->state.period && |
464 | state->duty_cycle == pwm->state.duty_cycle && | |
465 | state->polarity == pwm->state.polarity && | |
466 | state->enabled == pwm->state.enabled) | |
5ec803ed | 467 | return 0; |
76abbdde | 468 | |
5ec803ed BB |
469 | if (pwm->chip->ops->apply) { |
470 | err = pwm->chip->ops->apply(pwm->chip, pwm, state); | |
471 | if (err) | |
472 | return err; | |
0c2498f1 | 473 | |
5ec803ed BB |
474 | pwm->state = *state; |
475 | } else { | |
476 | /* | |
477 | * FIXME: restore the initial state in case of error. | |
478 | */ | |
479 | if (state->polarity != pwm->state.polarity) { | |
480 | if (!pwm->chip->ops->set_polarity) | |
481 | return -ENOTSUPP; | |
482 | ||
483 | /* | |
484 | * Changing the polarity of a running PWM is | |
485 | * only allowed when the PWM driver implements | |
486 | * ->apply(). | |
487 | */ | |
488 | if (pwm->state.enabled) { | |
489 | pwm->chip->ops->disable(pwm->chip, pwm); | |
490 | pwm->state.enabled = false; | |
491 | } | |
492 | ||
493 | err = pwm->chip->ops->set_polarity(pwm->chip, pwm, | |
494 | state->polarity); | |
495 | if (err) | |
496 | return err; | |
497 | ||
498 | pwm->state.polarity = state->polarity; | |
499 | } | |
76abbdde | 500 | |
5ec803ed BB |
501 | if (state->period != pwm->state.period || |
502 | state->duty_cycle != pwm->state.duty_cycle) { | |
503 | err = pwm->chip->ops->config(pwm->chip, pwm, | |
504 | state->duty_cycle, | |
505 | state->period); | |
506 | if (err) | |
507 | return err; | |
0aa0869c | 508 | |
5ec803ed BB |
509 | pwm->state.duty_cycle = state->duty_cycle; |
510 | pwm->state.period = state->period; | |
511 | } | |
0aa0869c | 512 | |
5ec803ed BB |
513 | if (state->enabled != pwm->state.enabled) { |
514 | if (state->enabled) { | |
515 | err = pwm->chip->ops->enable(pwm->chip, pwm); | |
516 | if (err) | |
517 | return err; | |
518 | } else { | |
519 | pwm->chip->ops->disable(pwm->chip, pwm); | |
520 | } | |
d1cd2142 | 521 | |
5ec803ed BB |
522 | pwm->state.enabled = state->enabled; |
523 | } | |
d1cd2142 | 524 | } |
0aa0869c | 525 | |
459a25af | 526 | return 0; |
0aa0869c | 527 | } |
5ec803ed | 528 | EXPORT_SYMBOL_GPL(pwm_apply_state); |
0aa0869c | 529 | |
3a3d1a4e LJ |
530 | /** |
531 | * pwm_capture() - capture and report a PWM signal | |
532 | * @pwm: PWM device | |
533 | * @result: structure to fill with capture result | |
534 | * @timeout: time to wait, in milliseconds, before giving up on capture | |
535 | * | |
536 | * Returns: 0 on success or a negative error code on failure. | |
537 | */ | |
538 | int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, | |
539 | unsigned long timeout) | |
540 | { | |
541 | int err; | |
542 | ||
543 | if (!pwm || !pwm->chip->ops) | |
544 | return -EINVAL; | |
545 | ||
546 | if (!pwm->chip->ops->capture) | |
547 | return -ENOSYS; | |
548 | ||
549 | mutex_lock(&pwm_lock); | |
550 | err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout); | |
551 | mutex_unlock(&pwm_lock); | |
552 | ||
553 | return err; | |
554 | } | |
555 | EXPORT_SYMBOL_GPL(pwm_capture); | |
556 | ||
0c2498f1 | 557 | /** |
5ec803ed | 558 | * pwm_adjust_config() - adjust the current PWM config to the PWM arguments |
0c2498f1 | 559 | * @pwm: PWM device |
04883802 | 560 | * |
5ec803ed BB |
561 | * This function will adjust the PWM config to the PWM arguments provided |
562 | * by the DT or PWM lookup table. This is particularly useful to adapt | |
563 | * the bootloader config to the Linux one. | |
0c2498f1 | 564 | */ |
5ec803ed | 565 | int pwm_adjust_config(struct pwm_device *pwm) |
0c2498f1 | 566 | { |
5ec803ed BB |
567 | struct pwm_state state; |
568 | struct pwm_args pargs; | |
d1cd2142 | 569 | |
5ec803ed BB |
570 | pwm_get_args(pwm, &pargs); |
571 | pwm_get_state(pwm, &state); | |
d1cd2142 | 572 | |
5ec803ed BB |
573 | /* |
574 | * If the current period is zero it means that either the PWM driver | |
575 | * does not support initial state retrieval or the PWM has not yet | |
576 | * been configured. | |
577 | * | |
578 | * In either case, we setup the new period and polarity, and assign a | |
579 | * duty cycle of 0. | |
580 | */ | |
581 | if (!state.period) { | |
582 | state.duty_cycle = 0; | |
583 | state.period = pargs.period; | |
584 | state.polarity = pargs.polarity; | |
d1cd2142 | 585 | |
5ec803ed | 586 | return pwm_apply_state(pwm, &state); |
d1cd2142 JR |
587 | } |
588 | ||
5ec803ed BB |
589 | /* |
590 | * Adjust the PWM duty cycle/period based on the period value provided | |
591 | * in PWM args. | |
592 | */ | |
593 | if (pargs.period != state.period) { | |
594 | u64 dutycycle = (u64)state.duty_cycle * pargs.period; | |
0c2498f1 | 595 | |
5ec803ed BB |
596 | do_div(dutycycle, state.period); |
597 | state.duty_cycle = dutycycle; | |
598 | state.period = pargs.period; | |
599 | } | |
0c2498f1 | 600 | |
5ec803ed BB |
601 | /* |
602 | * If the polarity changed, we should also change the duty cycle. | |
603 | */ | |
604 | if (pargs.polarity != state.polarity) { | |
605 | state.polarity = pargs.polarity; | |
606 | state.duty_cycle = state.period - state.duty_cycle; | |
09a7e4a3 | 607 | } |
5ec803ed BB |
608 | |
609 | return pwm_apply_state(pwm, &state); | |
0c2498f1 | 610 | } |
5ec803ed | 611 | EXPORT_SYMBOL_GPL(pwm_adjust_config); |
62099abf | 612 | |
7299ab70 TR |
613 | static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) |
614 | { | |
615 | struct pwm_chip *chip; | |
616 | ||
617 | mutex_lock(&pwm_lock); | |
618 | ||
619 | list_for_each_entry(chip, &pwm_chips, list) | |
620 | if (chip->dev && chip->dev->of_node == np) { | |
621 | mutex_unlock(&pwm_lock); | |
622 | return chip; | |
623 | } | |
624 | ||
625 | mutex_unlock(&pwm_lock); | |
626 | ||
627 | return ERR_PTR(-EPROBE_DEFER); | |
628 | } | |
629 | ||
b2c200e3 FG |
630 | static struct device_link *pwm_device_link_add(struct device *dev, |
631 | struct pwm_device *pwm) | |
632 | { | |
633 | struct device_link *dl; | |
634 | ||
635 | if (!dev) { | |
636 | /* | |
637 | * No device for the PWM consumer has been provided. It may | |
638 | * impact the PM sequence ordering: the PWM supplier may get | |
639 | * suspended before the consumer. | |
640 | */ | |
641 | dev_warn(pwm->chip->dev, | |
642 | "No consumer device specified to create a link to\n"); | |
643 | return NULL; | |
644 | } | |
645 | ||
646 | dl = device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER); | |
647 | if (!dl) { | |
648 | dev_err(dev, "failed to create device link to %s\n", | |
649 | dev_name(pwm->chip->dev)); | |
650 | return ERR_PTR(-EINVAL); | |
651 | } | |
652 | ||
653 | return dl; | |
654 | } | |
655 | ||
7299ab70 | 656 | /** |
8eb96127 | 657 | * of_pwm_get() - request a PWM via the PWM framework |
b2c200e3 | 658 | * @dev: device for PWM consumer |
7299ab70 TR |
659 | * @np: device node to get the PWM from |
660 | * @con_id: consumer name | |
661 | * | |
662 | * Returns the PWM device parsed from the phandle and index specified in the | |
663 | * "pwms" property of a device tree node or a negative error-code on failure. | |
664 | * Values parsed from the device tree are stored in the returned PWM device | |
665 | * object. | |
666 | * | |
667 | * If con_id is NULL, the first PWM device listed in the "pwms" property will | |
668 | * be requested. Otherwise the "pwm-names" property is used to do a reverse | |
669 | * lookup of the PWM index. This also means that the "pwm-names" property | |
670 | * becomes mandatory for devices that look up the PWM device via the con_id | |
671 | * parameter. | |
04883802 TR |
672 | * |
673 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
674 | * error code on failure. | |
7299ab70 | 675 | */ |
b2c200e3 FG |
676 | struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np, |
677 | const char *con_id) | |
7299ab70 TR |
678 | { |
679 | struct pwm_device *pwm = NULL; | |
680 | struct of_phandle_args args; | |
b2c200e3 | 681 | struct device_link *dl; |
7299ab70 TR |
682 | struct pwm_chip *pc; |
683 | int index = 0; | |
684 | int err; | |
685 | ||
686 | if (con_id) { | |
687 | index = of_property_match_string(np, "pwm-names", con_id); | |
688 | if (index < 0) | |
689 | return ERR_PTR(index); | |
690 | } | |
691 | ||
692 | err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index, | |
693 | &args); | |
694 | if (err) { | |
f2dafc09 | 695 | pr_err("%s(): can't parse \"pwms\" property\n", __func__); |
7299ab70 TR |
696 | return ERR_PTR(err); |
697 | } | |
698 | ||
699 | pc = of_node_to_pwmchip(args.np); | |
700 | if (IS_ERR(pc)) { | |
93c292ef JB |
701 | if (PTR_ERR(pc) != -EPROBE_DEFER) |
702 | pr_err("%s(): PWM chip not found\n", __func__); | |
703 | ||
7299ab70 TR |
704 | pwm = ERR_CAST(pc); |
705 | goto put; | |
706 | } | |
707 | ||
7299ab70 TR |
708 | pwm = pc->of_xlate(pc, &args); |
709 | if (IS_ERR(pwm)) | |
710 | goto put; | |
711 | ||
b2c200e3 FG |
712 | dl = pwm_device_link_add(dev, pwm); |
713 | if (IS_ERR(dl)) { | |
714 | /* of_xlate ended up calling pwm_request_from_chip() */ | |
715 | pwm_free(pwm); | |
716 | pwm = ERR_CAST(dl); | |
717 | goto put; | |
718 | } | |
719 | ||
7299ab70 TR |
720 | /* |
721 | * If a consumer name was not given, try to look it up from the | |
722 | * "pwm-names" property if it exists. Otherwise use the name of | |
723 | * the user device node. | |
724 | */ | |
725 | if (!con_id) { | |
726 | err = of_property_read_string_index(np, "pwm-names", index, | |
727 | &con_id); | |
728 | if (err < 0) | |
729 | con_id = np->name; | |
730 | } | |
731 | ||
732 | pwm->label = con_id; | |
733 | ||
734 | put: | |
735 | of_node_put(args.np); | |
736 | ||
737 | return pwm; | |
738 | } | |
8eb96127 | 739 | EXPORT_SYMBOL_GPL(of_pwm_get); |
7299ab70 | 740 | |
4a6ef8e3 NV |
741 | #if IS_ENABLED(CONFIG_ACPI) |
742 | static struct pwm_chip *device_to_pwmchip(struct device *dev) | |
743 | { | |
744 | struct pwm_chip *chip; | |
745 | ||
746 | mutex_lock(&pwm_lock); | |
747 | ||
748 | list_for_each_entry(chip, &pwm_chips, list) { | |
749 | struct acpi_device *adev = ACPI_COMPANION(chip->dev); | |
750 | ||
751 | if ((chip->dev == dev) || (adev && &adev->dev == dev)) { | |
752 | mutex_unlock(&pwm_lock); | |
753 | return chip; | |
754 | } | |
755 | } | |
756 | ||
757 | mutex_unlock(&pwm_lock); | |
758 | ||
759 | return ERR_PTR(-EPROBE_DEFER); | |
760 | } | |
761 | #endif | |
762 | ||
763 | /** | |
764 | * acpi_pwm_get() - request a PWM via parsing "pwms" property in ACPI | |
765 | * @fwnode: firmware node to get the "pwm" property from | |
766 | * | |
767 | * Returns the PWM device parsed from the fwnode and index specified in the | |
768 | * "pwms" property or a negative error-code on failure. | |
769 | * Values parsed from the device tree are stored in the returned PWM device | |
770 | * object. | |
771 | * | |
772 | * This is analogous to of_pwm_get() except con_id is not yet supported. | |
773 | * ACPI entries must look like | |
774 | * Package () {"pwms", Package () | |
775 | * { <PWM device reference>, <PWM index>, <PWM period> [, <PWM flags>]}} | |
776 | * | |
777 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
778 | * error code on failure. | |
779 | */ | |
780 | static struct pwm_device *acpi_pwm_get(struct fwnode_handle *fwnode) | |
781 | { | |
782 | struct pwm_device *pwm = ERR_PTR(-ENODEV); | |
783 | #if IS_ENABLED(CONFIG_ACPI) | |
784 | struct fwnode_reference_args args; | |
785 | struct acpi_device *acpi; | |
786 | struct pwm_chip *chip; | |
787 | int ret; | |
788 | ||
789 | memset(&args, 0, sizeof(args)); | |
790 | ||
791 | ret = __acpi_node_get_property_reference(fwnode, "pwms", 0, 3, &args); | |
792 | if (ret < 0) | |
793 | return ERR_PTR(ret); | |
794 | ||
795 | acpi = to_acpi_device_node(args.fwnode); | |
796 | if (!acpi) | |
797 | return ERR_PTR(-EINVAL); | |
798 | ||
799 | if (args.nargs < 2) | |
800 | return ERR_PTR(-EPROTO); | |
801 | ||
802 | chip = device_to_pwmchip(&acpi->dev); | |
803 | if (IS_ERR(chip)) | |
804 | return ERR_CAST(chip); | |
805 | ||
806 | pwm = pwm_request_from_chip(chip, args.args[0], NULL); | |
807 | if (IS_ERR(pwm)) | |
808 | return pwm; | |
809 | ||
810 | pwm->args.period = args.args[1]; | |
811 | pwm->args.polarity = PWM_POLARITY_NORMAL; | |
812 | ||
813 | if (args.nargs > 2 && args.args[2] & PWM_POLARITY_INVERTED) | |
814 | pwm->args.polarity = PWM_POLARITY_INVERSED; | |
815 | #endif | |
816 | ||
817 | return pwm; | |
818 | } | |
819 | ||
8138d2dd TR |
820 | /** |
821 | * pwm_add_table() - register PWM device consumers | |
822 | * @table: array of consumers to register | |
823 | * @num: number of consumers in table | |
824 | */ | |
c264f111 | 825 | void pwm_add_table(struct pwm_lookup *table, size_t num) |
8138d2dd TR |
826 | { |
827 | mutex_lock(&pwm_lookup_lock); | |
828 | ||
829 | while (num--) { | |
830 | list_add_tail(&table->list, &pwm_lookup_list); | |
831 | table++; | |
832 | } | |
833 | ||
834 | mutex_unlock(&pwm_lookup_lock); | |
835 | } | |
836 | ||
efb0de55 SK |
837 | /** |
838 | * pwm_remove_table() - unregister PWM device consumers | |
839 | * @table: array of consumers to unregister | |
840 | * @num: number of consumers in table | |
841 | */ | |
842 | void pwm_remove_table(struct pwm_lookup *table, size_t num) | |
843 | { | |
844 | mutex_lock(&pwm_lookup_lock); | |
845 | ||
846 | while (num--) { | |
847 | list_del(&table->list); | |
848 | table++; | |
849 | } | |
850 | ||
851 | mutex_unlock(&pwm_lookup_lock); | |
852 | } | |
853 | ||
8138d2dd TR |
854 | /** |
855 | * pwm_get() - look up and request a PWM device | |
856 | * @dev: device for PWM consumer | |
857 | * @con_id: consumer name | |
858 | * | |
7299ab70 TR |
859 | * Lookup is first attempted using DT. If the device was not instantiated from |
860 | * a device tree, a PWM chip and a relative index is looked up via a table | |
861 | * supplied by board setup code (see pwm_add_table()). | |
8138d2dd TR |
862 | * |
863 | * Once a PWM chip has been found the specified PWM device will be requested | |
864 | * and is ready to be used. | |
04883802 TR |
865 | * |
866 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
867 | * error code on failure. | |
8138d2dd TR |
868 | */ |
869 | struct pwm_device *pwm_get(struct device *dev, const char *con_id) | |
870 | { | |
e50d3523 | 871 | const char *dev_id = dev ? dev_name(dev) : NULL; |
69efb343 HG |
872 | struct pwm_device *pwm; |
873 | struct pwm_chip *chip; | |
b2c200e3 | 874 | struct device_link *dl; |
8138d2dd | 875 | unsigned int best = 0; |
70145f87 | 876 | struct pwm_lookup *p, *chosen = NULL; |
8138d2dd | 877 | unsigned int match; |
b526a314 | 878 | int err; |
8138d2dd | 879 | |
7299ab70 TR |
880 | /* look up via DT first */ |
881 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) | |
b2c200e3 | 882 | return of_pwm_get(dev, dev->of_node, con_id); |
7299ab70 | 883 | |
4a6ef8e3 | 884 | /* then lookup via ACPI */ |
6cf9481b HG |
885 | if (dev && is_acpi_node(dev->fwnode)) { |
886 | pwm = acpi_pwm_get(dev->fwnode); | |
887 | if (!IS_ERR(pwm) || PTR_ERR(pwm) != -ENOENT) | |
888 | return pwm; | |
889 | } | |
7299ab70 | 890 | |
8138d2dd TR |
891 | /* |
892 | * We look up the provider in the static table typically provided by | |
893 | * board setup code. We first try to lookup the consumer device by | |
894 | * name. If the consumer device was passed in as NULL or if no match | |
895 | * was found, we try to find the consumer by directly looking it up | |
896 | * by name. | |
897 | * | |
898 | * If a match is found, the provider PWM chip is looked up by name | |
899 | * and a PWM device is requested using the PWM device per-chip index. | |
900 | * | |
901 | * The lookup algorithm was shamelessly taken from the clock | |
902 | * framework: | |
903 | * | |
904 | * We do slightly fuzzy matching here: | |
905 | * An entry with a NULL ID is assumed to be a wildcard. | |
906 | * If an entry has a device ID, it must match | |
907 | * If an entry has a connection ID, it must match | |
908 | * Then we take the most specific entry - with the following order | |
909 | * of precedence: dev+con > dev only > con only. | |
910 | */ | |
911 | mutex_lock(&pwm_lookup_lock); | |
912 | ||
913 | list_for_each_entry(p, &pwm_lookup_list, list) { | |
914 | match = 0; | |
915 | ||
916 | if (p->dev_id) { | |
917 | if (!dev_id || strcmp(p->dev_id, dev_id)) | |
918 | continue; | |
919 | ||
920 | match += 2; | |
921 | } | |
922 | ||
923 | if (p->con_id) { | |
924 | if (!con_id || strcmp(p->con_id, con_id)) | |
925 | continue; | |
926 | ||
927 | match += 1; | |
928 | } | |
929 | ||
930 | if (match > best) { | |
70145f87 | 931 | chosen = p; |
8138d2dd TR |
932 | |
933 | if (match != 3) | |
934 | best = match; | |
935 | else | |
936 | break; | |
937 | } | |
938 | } | |
939 | ||
69efb343 HG |
940 | mutex_unlock(&pwm_lookup_lock); |
941 | ||
942 | if (!chosen) | |
943 | return ERR_PTR(-ENODEV); | |
3796ce1d | 944 | |
70145f87 | 945 | chip = pwmchip_find_by_name(chosen->provider); |
b526a314 HG |
946 | |
947 | /* | |
948 | * If the lookup entry specifies a module, load the module and retry | |
949 | * the PWM chip lookup. This can be used to work around driver load | |
950 | * ordering issues if driver's can't be made to properly support the | |
951 | * deferred probe mechanism. | |
952 | */ | |
953 | if (!chip && chosen->module) { | |
954 | err = request_module(chosen->module); | |
955 | if (err == 0) | |
956 | chip = pwmchip_find_by_name(chosen->provider); | |
957 | } | |
958 | ||
70145f87 | 959 | if (!chip) |
69efb343 | 960 | return ERR_PTR(-EPROBE_DEFER); |
3796ce1d | 961 | |
70145f87 GU |
962 | pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id); |
963 | if (IS_ERR(pwm)) | |
69efb343 | 964 | return pwm; |
8138d2dd | 965 | |
b2c200e3 FG |
966 | dl = pwm_device_link_add(dev, pwm); |
967 | if (IS_ERR(dl)) { | |
968 | pwm_free(pwm); | |
969 | return ERR_CAST(dl); | |
970 | } | |
971 | ||
fbd45a12 BB |
972 | pwm->args.period = chosen->period; |
973 | pwm->args.polarity = chosen->polarity; | |
974 | ||
8138d2dd TR |
975 | return pwm; |
976 | } | |
977 | EXPORT_SYMBOL_GPL(pwm_get); | |
978 | ||
979 | /** | |
980 | * pwm_put() - release a PWM device | |
981 | * @pwm: PWM device | |
982 | */ | |
983 | void pwm_put(struct pwm_device *pwm) | |
984 | { | |
985 | if (!pwm) | |
986 | return; | |
987 | ||
988 | mutex_lock(&pwm_lock); | |
989 | ||
990 | if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) { | |
e50d3523 | 991 | pr_warn("PWM device already freed\n"); |
8138d2dd TR |
992 | goto out; |
993 | } | |
994 | ||
995 | if (pwm->chip->ops->free) | |
996 | pwm->chip->ops->free(pwm->chip, pwm); | |
997 | ||
e926b12c | 998 | pwm_set_chip_data(pwm, NULL); |
8138d2dd TR |
999 | pwm->label = NULL; |
1000 | ||
1001 | module_put(pwm->chip->ops->owner); | |
1002 | out: | |
1003 | mutex_unlock(&pwm_lock); | |
1004 | } | |
1005 | EXPORT_SYMBOL_GPL(pwm_put); | |
1006 | ||
6354316d AC |
1007 | static void devm_pwm_release(struct device *dev, void *res) |
1008 | { | |
1009 | pwm_put(*(struct pwm_device **)res); | |
1010 | } | |
1011 | ||
1012 | /** | |
1013 | * devm_pwm_get() - resource managed pwm_get() | |
1014 | * @dev: device for PWM consumer | |
1015 | * @con_id: consumer name | |
1016 | * | |
1017 | * This function performs like pwm_get() but the acquired PWM device will | |
1018 | * automatically be released on driver detach. | |
04883802 TR |
1019 | * |
1020 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
1021 | * error code on failure. | |
6354316d AC |
1022 | */ |
1023 | struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id) | |
1024 | { | |
1025 | struct pwm_device **ptr, *pwm; | |
1026 | ||
77f0b9d2 | 1027 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
6354316d AC |
1028 | if (!ptr) |
1029 | return ERR_PTR(-ENOMEM); | |
1030 | ||
1031 | pwm = pwm_get(dev, con_id); | |
1032 | if (!IS_ERR(pwm)) { | |
1033 | *ptr = pwm; | |
1034 | devres_add(dev, ptr); | |
1035 | } else { | |
1036 | devres_free(ptr); | |
1037 | } | |
1038 | ||
1039 | return pwm; | |
1040 | } | |
1041 | EXPORT_SYMBOL_GPL(devm_pwm_get); | |
1042 | ||
261a5edd PU |
1043 | /** |
1044 | * devm_of_pwm_get() - resource managed of_pwm_get() | |
1045 | * @dev: device for PWM consumer | |
1046 | * @np: device node to get the PWM from | |
1047 | * @con_id: consumer name | |
1048 | * | |
1049 | * This function performs like of_pwm_get() but the acquired PWM device will | |
1050 | * automatically be released on driver detach. | |
04883802 TR |
1051 | * |
1052 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
1053 | * error code on failure. | |
261a5edd PU |
1054 | */ |
1055 | struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, | |
1056 | const char *con_id) | |
1057 | { | |
1058 | struct pwm_device **ptr, *pwm; | |
1059 | ||
77f0b9d2 | 1060 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
261a5edd PU |
1061 | if (!ptr) |
1062 | return ERR_PTR(-ENOMEM); | |
1063 | ||
b2c200e3 | 1064 | pwm = of_pwm_get(dev, np, con_id); |
261a5edd PU |
1065 | if (!IS_ERR(pwm)) { |
1066 | *ptr = pwm; | |
1067 | devres_add(dev, ptr); | |
1068 | } else { | |
1069 | devres_free(ptr); | |
1070 | } | |
1071 | ||
1072 | return pwm; | |
1073 | } | |
1074 | EXPORT_SYMBOL_GPL(devm_of_pwm_get); | |
1075 | ||
4a6ef8e3 NV |
1076 | /** |
1077 | * devm_fwnode_pwm_get() - request a resource managed PWM from firmware node | |
1078 | * @dev: device for PWM consumer | |
1079 | * @fwnode: firmware node to get the PWM from | |
1080 | * @con_id: consumer name | |
1081 | * | |
1082 | * Returns the PWM device parsed from the firmware node. See of_pwm_get() and | |
1083 | * acpi_pwm_get() for a detailed description. | |
1084 | * | |
1085 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
1086 | * error code on failure. | |
1087 | */ | |
1088 | struct pwm_device *devm_fwnode_pwm_get(struct device *dev, | |
1089 | struct fwnode_handle *fwnode, | |
1090 | const char *con_id) | |
1091 | { | |
1092 | struct pwm_device **ptr, *pwm = ERR_PTR(-ENODEV); | |
1093 | ||
1094 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); | |
1095 | if (!ptr) | |
1096 | return ERR_PTR(-ENOMEM); | |
1097 | ||
1098 | if (is_of_node(fwnode)) | |
1099 | pwm = of_pwm_get(dev, to_of_node(fwnode), con_id); | |
1100 | else if (is_acpi_node(fwnode)) | |
1101 | pwm = acpi_pwm_get(fwnode); | |
1102 | ||
1103 | if (!IS_ERR(pwm)) { | |
1104 | *ptr = pwm; | |
1105 | devres_add(dev, ptr); | |
1106 | } else { | |
1107 | devres_free(ptr); | |
1108 | } | |
1109 | ||
1110 | return pwm; | |
1111 | } | |
1112 | EXPORT_SYMBOL_GPL(devm_fwnode_pwm_get); | |
1113 | ||
6354316d AC |
1114 | static int devm_pwm_match(struct device *dev, void *res, void *data) |
1115 | { | |
1116 | struct pwm_device **p = res; | |
1117 | ||
1118 | if (WARN_ON(!p || !*p)) | |
1119 | return 0; | |
1120 | ||
1121 | return *p == data; | |
1122 | } | |
1123 | ||
1124 | /** | |
1125 | * devm_pwm_put() - resource managed pwm_put() | |
1126 | * @dev: device for PWM consumer | |
1127 | * @pwm: PWM device | |
1128 | * | |
1129 | * Release a PWM previously allocated using devm_pwm_get(). Calling this | |
1130 | * function is usually not needed because devm-allocated resources are | |
1131 | * automatically released on driver detach. | |
1132 | */ | |
1133 | void devm_pwm_put(struct device *dev, struct pwm_device *pwm) | |
1134 | { | |
1135 | WARN_ON(devres_release(dev, devm_pwm_release, devm_pwm_match, pwm)); | |
1136 | } | |
1137 | EXPORT_SYMBOL_GPL(devm_pwm_put); | |
1138 | ||
62099abf TR |
1139 | #ifdef CONFIG_DEBUG_FS |
1140 | static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) | |
1141 | { | |
1142 | unsigned int i; | |
1143 | ||
1144 | for (i = 0; i < chip->npwm; i++) { | |
1145 | struct pwm_device *pwm = &chip->pwms[i]; | |
39100cee BB |
1146 | struct pwm_state state; |
1147 | ||
1148 | pwm_get_state(pwm, &state); | |
62099abf TR |
1149 | |
1150 | seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label); | |
1151 | ||
1152 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) | |
adcba1e3 | 1153 | seq_puts(s, " requested"); |
62099abf | 1154 | |
39100cee | 1155 | if (state.enabled) |
adcba1e3 | 1156 | seq_puts(s, " enabled"); |
62099abf | 1157 | |
23e3523f HS |
1158 | seq_printf(s, " period: %u ns", state.period); |
1159 | seq_printf(s, " duty: %u ns", state.duty_cycle); | |
1160 | seq_printf(s, " polarity: %s", | |
1161 | state.polarity ? "inverse" : "normal"); | |
1162 | ||
adcba1e3 | 1163 | seq_puts(s, "\n"); |
62099abf TR |
1164 | } |
1165 | } | |
1166 | ||
1167 | static void *pwm_seq_start(struct seq_file *s, loff_t *pos) | |
1168 | { | |
1169 | mutex_lock(&pwm_lock); | |
1170 | s->private = ""; | |
1171 | ||
1172 | return seq_list_start(&pwm_chips, *pos); | |
1173 | } | |
1174 | ||
1175 | static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
1176 | { | |
1177 | s->private = "\n"; | |
1178 | ||
1179 | return seq_list_next(v, &pwm_chips, pos); | |
1180 | } | |
1181 | ||
1182 | static void pwm_seq_stop(struct seq_file *s, void *v) | |
1183 | { | |
1184 | mutex_unlock(&pwm_lock); | |
1185 | } | |
1186 | ||
1187 | static int pwm_seq_show(struct seq_file *s, void *v) | |
1188 | { | |
1189 | struct pwm_chip *chip = list_entry(v, struct pwm_chip, list); | |
1190 | ||
1191 | seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private, | |
1192 | chip->dev->bus ? chip->dev->bus->name : "no-bus", | |
1193 | dev_name(chip->dev), chip->npwm, | |
1194 | (chip->npwm != 1) ? "s" : ""); | |
1195 | ||
cc2d2247 | 1196 | pwm_dbg_show(chip, s); |
62099abf TR |
1197 | |
1198 | return 0; | |
1199 | } | |
1200 | ||
1201 | static const struct seq_operations pwm_seq_ops = { | |
1202 | .start = pwm_seq_start, | |
1203 | .next = pwm_seq_next, | |
1204 | .stop = pwm_seq_stop, | |
1205 | .show = pwm_seq_show, | |
1206 | }; | |
1207 | ||
1208 | static int pwm_seq_open(struct inode *inode, struct file *file) | |
1209 | { | |
1210 | return seq_open(file, &pwm_seq_ops); | |
1211 | } | |
1212 | ||
1213 | static const struct file_operations pwm_debugfs_ops = { | |
1214 | .owner = THIS_MODULE, | |
1215 | .open = pwm_seq_open, | |
1216 | .read = seq_read, | |
1217 | .llseek = seq_lseek, | |
1218 | .release = seq_release, | |
1219 | }; | |
1220 | ||
1221 | static int __init pwm_debugfs_init(void) | |
1222 | { | |
1223 | debugfs_create_file("pwm", S_IFREG | S_IRUGO, NULL, NULL, | |
1224 | &pwm_debugfs_ops); | |
1225 | ||
1226 | return 0; | |
1227 | } | |
62099abf TR |
1228 | subsys_initcall(pwm_debugfs_init); |
1229 | #endif /* CONFIG_DEBUG_FS */ |