Commit | Line | Data |
---|---|---|
0c2498f1 SH |
1 | /* |
2 | * Generic pwmlib implementation | |
3 | * | |
4 | * Copyright (C) 2011 Sascha Hauer <s.hauer@pengutronix.de> | |
f051c466 | 5 | * Copyright (C) 2011-2012 Avionic Design GmbH |
0c2498f1 SH |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2, or (at your option) | |
10 | * any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; see the file COPYING. If not, write to | |
19 | * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. | |
20 | */ | |
21 | ||
22 | #include <linux/module.h> | |
23 | #include <linux/pwm.h> | |
f051c466 | 24 | #include <linux/radix-tree.h> |
0c2498f1 SH |
25 | #include <linux/list.h> |
26 | #include <linux/mutex.h> | |
27 | #include <linux/err.h> | |
28 | #include <linux/slab.h> | |
29 | #include <linux/device.h> | |
62099abf TR |
30 | #include <linux/debugfs.h> |
31 | #include <linux/seq_file.h> | |
0c2498f1 | 32 | |
208be769 | 33 | #include <dt-bindings/pwm/pwm.h> |
0c2498f1 | 34 | |
208be769 | 35 | #define MAX_PWMS 1024 |
83af2402 | 36 | |
8138d2dd TR |
37 | static DEFINE_MUTEX(pwm_lookup_lock); |
38 | static LIST_HEAD(pwm_lookup_list); | |
0c2498f1 | 39 | static DEFINE_MUTEX(pwm_lock); |
f051c466 TR |
40 | static LIST_HEAD(pwm_chips); |
41 | static DECLARE_BITMAP(allocated_pwms, MAX_PWMS); | |
42 | static RADIX_TREE(pwm_tree, GFP_KERNEL); | |
0c2498f1 | 43 | |
f051c466 | 44 | static struct pwm_device *pwm_to_device(unsigned int pwm) |
0c2498f1 | 45 | { |
f051c466 TR |
46 | return radix_tree_lookup(&pwm_tree, pwm); |
47 | } | |
48 | ||
49 | static int alloc_pwms(int pwm, unsigned int count) | |
50 | { | |
51 | unsigned int from = 0; | |
52 | unsigned int start; | |
53 | ||
54 | if (pwm >= MAX_PWMS) | |
55 | return -EINVAL; | |
56 | ||
57 | if (pwm >= 0) | |
58 | from = pwm; | |
0c2498f1 | 59 | |
f051c466 TR |
60 | start = bitmap_find_next_zero_area(allocated_pwms, MAX_PWMS, from, |
61 | count, 0); | |
62 | ||
63 | if (pwm >= 0 && start != pwm) | |
64 | return -EEXIST; | |
65 | ||
66 | if (start + count > MAX_PWMS) | |
67 | return -ENOSPC; | |
68 | ||
69 | return start; | |
70 | } | |
71 | ||
72 | static void free_pwms(struct pwm_chip *chip) | |
73 | { | |
74 | unsigned int i; | |
75 | ||
76 | for (i = 0; i < chip->npwm; i++) { | |
77 | struct pwm_device *pwm = &chip->pwms[i]; | |
83a98864 | 78 | |
f051c466 | 79 | radix_tree_delete(&pwm_tree, pwm->pwm); |
0c2498f1 SH |
80 | } |
81 | ||
f051c466 TR |
82 | bitmap_clear(allocated_pwms, chip->base, chip->npwm); |
83 | ||
84 | kfree(chip->pwms); | |
85 | chip->pwms = NULL; | |
86 | } | |
87 | ||
8138d2dd TR |
88 | static struct pwm_chip *pwmchip_find_by_name(const char *name) |
89 | { | |
90 | struct pwm_chip *chip; | |
91 | ||
92 | if (!name) | |
93 | return NULL; | |
94 | ||
95 | mutex_lock(&pwm_lock); | |
96 | ||
97 | list_for_each_entry(chip, &pwm_chips, list) { | |
98 | const char *chip_name = dev_name(chip->dev); | |
99 | ||
100 | if (chip_name && strcmp(chip_name, name) == 0) { | |
101 | mutex_unlock(&pwm_lock); | |
102 | return chip; | |
103 | } | |
104 | } | |
105 | ||
106 | mutex_unlock(&pwm_lock); | |
107 | ||
108 | return NULL; | |
109 | } | |
110 | ||
f051c466 TR |
111 | static int pwm_device_request(struct pwm_device *pwm, const char *label) |
112 | { | |
113 | int err; | |
114 | ||
115 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) | |
116 | return -EBUSY; | |
117 | ||
118 | if (!try_module_get(pwm->chip->ops->owner)) | |
119 | return -ENODEV; | |
120 | ||
121 | if (pwm->chip->ops->request) { | |
122 | err = pwm->chip->ops->request(pwm->chip, pwm); | |
123 | if (err) { | |
124 | module_put(pwm->chip->ops->owner); | |
125 | return err; | |
126 | } | |
127 | } | |
128 | ||
129 | set_bit(PWMF_REQUESTED, &pwm->flags); | |
130 | pwm->label = label; | |
131 | ||
132 | return 0; | |
133 | } | |
134 | ||
83af2402 PA |
135 | struct pwm_device * |
136 | of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) | |
137 | { | |
138 | struct pwm_device *pwm; | |
139 | ||
42883cbc | 140 | /* check, whether the driver supports a third cell for flags */ |
83af2402 PA |
141 | if (pc->of_pwm_n_cells < 3) |
142 | return ERR_PTR(-EINVAL); | |
143 | ||
42883cbc LW |
144 | /* flags in the third cell are optional */ |
145 | if (args->args_count < 2) | |
146 | return ERR_PTR(-EINVAL); | |
147 | ||
83af2402 PA |
148 | if (args->args[0] >= pc->npwm) |
149 | return ERR_PTR(-EINVAL); | |
150 | ||
151 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); | |
152 | if (IS_ERR(pwm)) | |
153 | return pwm; | |
154 | ||
e39c0df1 | 155 | pwm->args.period = args->args[1]; |
42883cbc | 156 | pwm->args.polarity = PWM_POLARITY_NORMAL; |
83af2402 | 157 | |
42883cbc | 158 | if (args->args_count > 2 && args->args[2] & PWM_POLARITY_INVERTED) |
e39c0df1 | 159 | pwm->args.polarity = PWM_POLARITY_INVERSED; |
83af2402 PA |
160 | |
161 | return pwm; | |
162 | } | |
417328c3 | 163 | EXPORT_SYMBOL_GPL(of_pwm_xlate_with_flags); |
83af2402 | 164 | |
e50d3523 SK |
165 | static struct pwm_device * |
166 | of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args) | |
7299ab70 TR |
167 | { |
168 | struct pwm_device *pwm; | |
169 | ||
42883cbc | 170 | /* sanity check driver support */ |
7299ab70 TR |
171 | if (pc->of_pwm_n_cells < 2) |
172 | return ERR_PTR(-EINVAL); | |
173 | ||
42883cbc LW |
174 | /* all cells are required */ |
175 | if (args->args_count != pc->of_pwm_n_cells) | |
176 | return ERR_PTR(-EINVAL); | |
177 | ||
7299ab70 TR |
178 | if (args->args[0] >= pc->npwm) |
179 | return ERR_PTR(-EINVAL); | |
180 | ||
181 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); | |
182 | if (IS_ERR(pwm)) | |
183 | return pwm; | |
184 | ||
e39c0df1 | 185 | pwm->args.period = args->args[1]; |
7299ab70 TR |
186 | |
187 | return pwm; | |
188 | } | |
189 | ||
dfeb86ec | 190 | static void of_pwmchip_add(struct pwm_chip *chip) |
7299ab70 TR |
191 | { |
192 | if (!chip->dev || !chip->dev->of_node) | |
193 | return; | |
194 | ||
195 | if (!chip->of_xlate) { | |
196 | chip->of_xlate = of_pwm_simple_xlate; | |
197 | chip->of_pwm_n_cells = 2; | |
198 | } | |
199 | ||
200 | of_node_get(chip->dev->of_node); | |
201 | } | |
202 | ||
dfeb86ec | 203 | static void of_pwmchip_remove(struct pwm_chip *chip) |
7299ab70 | 204 | { |
8d6cc073 | 205 | if (chip->dev) |
7299ab70 TR |
206 | of_node_put(chip->dev->of_node); |
207 | } | |
208 | ||
f051c466 TR |
209 | /** |
210 | * pwm_set_chip_data() - set private chip data for a PWM | |
211 | * @pwm: PWM device | |
212 | * @data: pointer to chip-specific data | |
04883802 TR |
213 | * |
214 | * Returns: 0 on success or a negative error code on failure. | |
f051c466 TR |
215 | */ |
216 | int pwm_set_chip_data(struct pwm_device *pwm, void *data) | |
217 | { | |
218 | if (!pwm) | |
219 | return -EINVAL; | |
220 | ||
221 | pwm->chip_data = data; | |
222 | ||
223 | return 0; | |
224 | } | |
928c4477 | 225 | EXPORT_SYMBOL_GPL(pwm_set_chip_data); |
f051c466 TR |
226 | |
227 | /** | |
228 | * pwm_get_chip_data() - get private chip data for a PWM | |
229 | * @pwm: PWM device | |
04883802 TR |
230 | * |
231 | * Returns: A pointer to the chip-private data for the PWM device. | |
f051c466 TR |
232 | */ |
233 | void *pwm_get_chip_data(struct pwm_device *pwm) | |
234 | { | |
235 | return pwm ? pwm->chip_data : NULL; | |
0c2498f1 | 236 | } |
928c4477 | 237 | EXPORT_SYMBOL_GPL(pwm_get_chip_data); |
0c2498f1 | 238 | |
5ec803ed BB |
239 | static bool pwm_ops_check(const struct pwm_ops *ops) |
240 | { | |
241 | /* driver supports legacy, non-atomic operation */ | |
242 | if (ops->config && ops->enable && ops->disable) | |
243 | return true; | |
244 | ||
245 | /* driver supports atomic operation */ | |
246 | if (ops->apply) | |
247 | return true; | |
248 | ||
249 | return false; | |
250 | } | |
251 | ||
0c2498f1 | 252 | /** |
b6a00fae | 253 | * pwmchip_add_with_polarity() - register a new PWM chip |
0c2498f1 | 254 | * @chip: the PWM chip to add |
b6a00fae | 255 | * @polarity: initial polarity of PWM channels |
f051c466 TR |
256 | * |
257 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base | |
b6a00fae TK |
258 | * will be used. The initial polarity for all channels is specified by the |
259 | * @polarity parameter. | |
04883802 TR |
260 | * |
261 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 | 262 | */ |
b6a00fae TK |
263 | int pwmchip_add_with_polarity(struct pwm_chip *chip, |
264 | enum pwm_polarity polarity) | |
0c2498f1 SH |
265 | { |
266 | struct pwm_device *pwm; | |
f051c466 TR |
267 | unsigned int i; |
268 | int ret; | |
0c2498f1 | 269 | |
5ec803ed BB |
270 | if (!chip || !chip->dev || !chip->ops || !chip->npwm) |
271 | return -EINVAL; | |
272 | ||
273 | if (!pwm_ops_check(chip->ops)) | |
f051c466 | 274 | return -EINVAL; |
0c2498f1 SH |
275 | |
276 | mutex_lock(&pwm_lock); | |
277 | ||
f051c466 TR |
278 | ret = alloc_pwms(chip->base, chip->npwm); |
279 | if (ret < 0) | |
280 | goto out; | |
281 | ||
2907f8ab | 282 | chip->pwms = kcalloc(chip->npwm, sizeof(*pwm), GFP_KERNEL); |
f051c466 TR |
283 | if (!chip->pwms) { |
284 | ret = -ENOMEM; | |
0c2498f1 SH |
285 | goto out; |
286 | } | |
287 | ||
f051c466 TR |
288 | chip->base = ret; |
289 | ||
290 | for (i = 0; i < chip->npwm; i++) { | |
291 | pwm = &chip->pwms[i]; | |
292 | ||
293 | pwm->chip = chip; | |
294 | pwm->pwm = chip->base + i; | |
295 | pwm->hwpwm = i; | |
43a276b0 | 296 | pwm->state.polarity = polarity; |
0c2498f1 | 297 | |
15fa8a43 BB |
298 | if (chip->ops->get_state) |
299 | chip->ops->get_state(chip, pwm, &pwm->state); | |
0c2498f1 | 300 | |
f051c466 TR |
301 | radix_tree_insert(&pwm_tree, pwm->pwm, pwm); |
302 | } | |
303 | ||
304 | bitmap_set(allocated_pwms, chip->base, chip->npwm); | |
305 | ||
306 | INIT_LIST_HEAD(&chip->list); | |
307 | list_add(&chip->list, &pwm_chips); | |
0c2498f1 | 308 | |
f051c466 TR |
309 | ret = 0; |
310 | ||
7299ab70 TR |
311 | if (IS_ENABLED(CONFIG_OF)) |
312 | of_pwmchip_add(chip); | |
313 | ||
76abbdde HS |
314 | pwmchip_sysfs_export(chip); |
315 | ||
f051c466 TR |
316 | out: |
317 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
318 | return ret; |
319 | } | |
b6a00fae TK |
320 | EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity); |
321 | ||
322 | /** | |
323 | * pwmchip_add() - register a new PWM chip | |
324 | * @chip: the PWM chip to add | |
325 | * | |
326 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base | |
327 | * will be used. The initial polarity for all channels is normal. | |
04883802 TR |
328 | * |
329 | * Returns: 0 on success or a negative error code on failure. | |
b6a00fae TK |
330 | */ |
331 | int pwmchip_add(struct pwm_chip *chip) | |
332 | { | |
333 | return pwmchip_add_with_polarity(chip, PWM_POLARITY_NORMAL); | |
334 | } | |
0c2498f1 SH |
335 | EXPORT_SYMBOL_GPL(pwmchip_add); |
336 | ||
337 | /** | |
338 | * pwmchip_remove() - remove a PWM chip | |
339 | * @chip: the PWM chip to remove | |
340 | * | |
341 | * Removes a PWM chip. This function may return busy if the PWM chip provides | |
342 | * a PWM device that is still requested. | |
04883802 TR |
343 | * |
344 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 SH |
345 | */ |
346 | int pwmchip_remove(struct pwm_chip *chip) | |
347 | { | |
f051c466 | 348 | unsigned int i; |
0c2498f1 SH |
349 | int ret = 0; |
350 | ||
0733424c DH |
351 | pwmchip_sysfs_unexport_children(chip); |
352 | ||
0c2498f1 SH |
353 | mutex_lock(&pwm_lock); |
354 | ||
f051c466 TR |
355 | for (i = 0; i < chip->npwm; i++) { |
356 | struct pwm_device *pwm = &chip->pwms[i]; | |
0c2498f1 | 357 | |
f051c466 TR |
358 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) { |
359 | ret = -EBUSY; | |
360 | goto out; | |
361 | } | |
0c2498f1 SH |
362 | } |
363 | ||
f051c466 | 364 | list_del_init(&chip->list); |
7299ab70 TR |
365 | |
366 | if (IS_ENABLED(CONFIG_OF)) | |
367 | of_pwmchip_remove(chip); | |
368 | ||
f051c466 | 369 | free_pwms(chip); |
0c2498f1 | 370 | |
76abbdde HS |
371 | pwmchip_sysfs_unexport(chip); |
372 | ||
0c2498f1 SH |
373 | out: |
374 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
375 | return ret; |
376 | } | |
377 | EXPORT_SYMBOL_GPL(pwmchip_remove); | |
378 | ||
379 | /** | |
380 | * pwm_request() - request a PWM device | |
04883802 | 381 | * @pwm: global PWM device index |
0c2498f1 | 382 | * @label: PWM device label |
8138d2dd TR |
383 | * |
384 | * This function is deprecated, use pwm_get() instead. | |
04883802 TR |
385 | * |
386 | * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on | |
387 | * failure. | |
0c2498f1 | 388 | */ |
f051c466 | 389 | struct pwm_device *pwm_request(int pwm, const char *label) |
0c2498f1 | 390 | { |
f051c466 TR |
391 | struct pwm_device *dev; |
392 | int err; | |
393 | ||
394 | if (pwm < 0 || pwm >= MAX_PWMS) | |
395 | return ERR_PTR(-EINVAL); | |
0c2498f1 SH |
396 | |
397 | mutex_lock(&pwm_lock); | |
398 | ||
f051c466 TR |
399 | dev = pwm_to_device(pwm); |
400 | if (!dev) { | |
401 | dev = ERR_PTR(-EPROBE_DEFER); | |
0c2498f1 SH |
402 | goto out; |
403 | } | |
404 | ||
f051c466 TR |
405 | err = pwm_device_request(dev, label); |
406 | if (err < 0) | |
407 | dev = ERR_PTR(err); | |
0c2498f1 | 408 | |
f051c466 TR |
409 | out: |
410 | mutex_unlock(&pwm_lock); | |
0c2498f1 | 411 | |
f051c466 TR |
412 | return dev; |
413 | } | |
414 | EXPORT_SYMBOL_GPL(pwm_request); | |
0c2498f1 | 415 | |
f051c466 TR |
416 | /** |
417 | * pwm_request_from_chip() - request a PWM device relative to a PWM chip | |
418 | * @chip: PWM chip | |
419 | * @index: per-chip index of the PWM to request | |
420 | * @label: a literal description string of this PWM | |
421 | * | |
04883802 TR |
422 | * Returns: A pointer to the PWM device at the given index of the given PWM |
423 | * chip. A negative error code is returned if the index is not valid for the | |
424 | * specified PWM chip or if the PWM device cannot be requested. | |
f051c466 TR |
425 | */ |
426 | struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, | |
427 | unsigned int index, | |
428 | const char *label) | |
429 | { | |
430 | struct pwm_device *pwm; | |
431 | int err; | |
0c2498f1 | 432 | |
f051c466 TR |
433 | if (!chip || index >= chip->npwm) |
434 | return ERR_PTR(-EINVAL); | |
0c2498f1 | 435 | |
f051c466 TR |
436 | mutex_lock(&pwm_lock); |
437 | pwm = &chip->pwms[index]; | |
0c2498f1 | 438 | |
f051c466 TR |
439 | err = pwm_device_request(pwm, label); |
440 | if (err < 0) | |
441 | pwm = ERR_PTR(err); | |
442 | ||
443 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
444 | return pwm; |
445 | } | |
f051c466 | 446 | EXPORT_SYMBOL_GPL(pwm_request_from_chip); |
0c2498f1 SH |
447 | |
448 | /** | |
449 | * pwm_free() - free a PWM device | |
450 | * @pwm: PWM device | |
8138d2dd TR |
451 | * |
452 | * This function is deprecated, use pwm_put() instead. | |
0c2498f1 SH |
453 | */ |
454 | void pwm_free(struct pwm_device *pwm) | |
455 | { | |
8138d2dd | 456 | pwm_put(pwm); |
0c2498f1 SH |
457 | } |
458 | EXPORT_SYMBOL_GPL(pwm_free); | |
459 | ||
460 | /** | |
5ec803ed | 461 | * pwm_apply_state() - atomically apply a new state to a PWM device |
0c2498f1 | 462 | * @pwm: PWM device |
5ec803ed BB |
463 | * @state: new state to apply. This can be adjusted by the PWM driver |
464 | * if the requested config is not achievable, for example, | |
465 | * ->duty_cycle and ->period might be approximated. | |
0c2498f1 | 466 | */ |
5ec803ed | 467 | int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state) |
0c2498f1 | 468 | { |
76abbdde HS |
469 | int err; |
470 | ||
ef2bf499 BN |
471 | if (!pwm || !state || !state->period || |
472 | state->duty_cycle > state->period) | |
f051c466 TR |
473 | return -EINVAL; |
474 | ||
309b32fb UKK |
475 | if (state->period == pwm->state.period && |
476 | state->duty_cycle == pwm->state.duty_cycle && | |
477 | state->polarity == pwm->state.polarity && | |
478 | state->enabled == pwm->state.enabled) | |
5ec803ed | 479 | return 0; |
76abbdde | 480 | |
5ec803ed BB |
481 | if (pwm->chip->ops->apply) { |
482 | err = pwm->chip->ops->apply(pwm->chip, pwm, state); | |
483 | if (err) | |
484 | return err; | |
0c2498f1 | 485 | |
5ec803ed BB |
486 | pwm->state = *state; |
487 | } else { | |
488 | /* | |
489 | * FIXME: restore the initial state in case of error. | |
490 | */ | |
491 | if (state->polarity != pwm->state.polarity) { | |
492 | if (!pwm->chip->ops->set_polarity) | |
493 | return -ENOTSUPP; | |
494 | ||
495 | /* | |
496 | * Changing the polarity of a running PWM is | |
497 | * only allowed when the PWM driver implements | |
498 | * ->apply(). | |
499 | */ | |
500 | if (pwm->state.enabled) { | |
501 | pwm->chip->ops->disable(pwm->chip, pwm); | |
502 | pwm->state.enabled = false; | |
503 | } | |
504 | ||
505 | err = pwm->chip->ops->set_polarity(pwm->chip, pwm, | |
506 | state->polarity); | |
507 | if (err) | |
508 | return err; | |
509 | ||
510 | pwm->state.polarity = state->polarity; | |
511 | } | |
76abbdde | 512 | |
5ec803ed BB |
513 | if (state->period != pwm->state.period || |
514 | state->duty_cycle != pwm->state.duty_cycle) { | |
515 | err = pwm->chip->ops->config(pwm->chip, pwm, | |
516 | state->duty_cycle, | |
517 | state->period); | |
518 | if (err) | |
519 | return err; | |
0aa0869c | 520 | |
5ec803ed BB |
521 | pwm->state.duty_cycle = state->duty_cycle; |
522 | pwm->state.period = state->period; | |
523 | } | |
0aa0869c | 524 | |
5ec803ed BB |
525 | if (state->enabled != pwm->state.enabled) { |
526 | if (state->enabled) { | |
527 | err = pwm->chip->ops->enable(pwm->chip, pwm); | |
528 | if (err) | |
529 | return err; | |
530 | } else { | |
531 | pwm->chip->ops->disable(pwm->chip, pwm); | |
532 | } | |
d1cd2142 | 533 | |
5ec803ed BB |
534 | pwm->state.enabled = state->enabled; |
535 | } | |
d1cd2142 | 536 | } |
0aa0869c | 537 | |
459a25af | 538 | return 0; |
0aa0869c | 539 | } |
5ec803ed | 540 | EXPORT_SYMBOL_GPL(pwm_apply_state); |
0aa0869c | 541 | |
3a3d1a4e LJ |
542 | /** |
543 | * pwm_capture() - capture and report a PWM signal | |
544 | * @pwm: PWM device | |
545 | * @result: structure to fill with capture result | |
546 | * @timeout: time to wait, in milliseconds, before giving up on capture | |
547 | * | |
548 | * Returns: 0 on success or a negative error code on failure. | |
549 | */ | |
550 | int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, | |
551 | unsigned long timeout) | |
552 | { | |
553 | int err; | |
554 | ||
555 | if (!pwm || !pwm->chip->ops) | |
556 | return -EINVAL; | |
557 | ||
558 | if (!pwm->chip->ops->capture) | |
559 | return -ENOSYS; | |
560 | ||
561 | mutex_lock(&pwm_lock); | |
562 | err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout); | |
563 | mutex_unlock(&pwm_lock); | |
564 | ||
565 | return err; | |
566 | } | |
567 | EXPORT_SYMBOL_GPL(pwm_capture); | |
568 | ||
0c2498f1 | 569 | /** |
5ec803ed | 570 | * pwm_adjust_config() - adjust the current PWM config to the PWM arguments |
0c2498f1 | 571 | * @pwm: PWM device |
04883802 | 572 | * |
5ec803ed BB |
573 | * This function will adjust the PWM config to the PWM arguments provided |
574 | * by the DT or PWM lookup table. This is particularly useful to adapt | |
575 | * the bootloader config to the Linux one. | |
0c2498f1 | 576 | */ |
5ec803ed | 577 | int pwm_adjust_config(struct pwm_device *pwm) |
0c2498f1 | 578 | { |
5ec803ed BB |
579 | struct pwm_state state; |
580 | struct pwm_args pargs; | |
d1cd2142 | 581 | |
5ec803ed BB |
582 | pwm_get_args(pwm, &pargs); |
583 | pwm_get_state(pwm, &state); | |
d1cd2142 | 584 | |
5ec803ed BB |
585 | /* |
586 | * If the current period is zero it means that either the PWM driver | |
587 | * does not support initial state retrieval or the PWM has not yet | |
588 | * been configured. | |
589 | * | |
590 | * In either case, we setup the new period and polarity, and assign a | |
591 | * duty cycle of 0. | |
592 | */ | |
593 | if (!state.period) { | |
594 | state.duty_cycle = 0; | |
595 | state.period = pargs.period; | |
596 | state.polarity = pargs.polarity; | |
d1cd2142 | 597 | |
5ec803ed | 598 | return pwm_apply_state(pwm, &state); |
d1cd2142 JR |
599 | } |
600 | ||
5ec803ed BB |
601 | /* |
602 | * Adjust the PWM duty cycle/period based on the period value provided | |
603 | * in PWM args. | |
604 | */ | |
605 | if (pargs.period != state.period) { | |
606 | u64 dutycycle = (u64)state.duty_cycle * pargs.period; | |
0c2498f1 | 607 | |
5ec803ed BB |
608 | do_div(dutycycle, state.period); |
609 | state.duty_cycle = dutycycle; | |
610 | state.period = pargs.period; | |
611 | } | |
0c2498f1 | 612 | |
5ec803ed BB |
613 | /* |
614 | * If the polarity changed, we should also change the duty cycle. | |
615 | */ | |
616 | if (pargs.polarity != state.polarity) { | |
617 | state.polarity = pargs.polarity; | |
618 | state.duty_cycle = state.period - state.duty_cycle; | |
09a7e4a3 | 619 | } |
5ec803ed BB |
620 | |
621 | return pwm_apply_state(pwm, &state); | |
0c2498f1 | 622 | } |
5ec803ed | 623 | EXPORT_SYMBOL_GPL(pwm_adjust_config); |
62099abf | 624 | |
7299ab70 TR |
625 | static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) |
626 | { | |
627 | struct pwm_chip *chip; | |
628 | ||
629 | mutex_lock(&pwm_lock); | |
630 | ||
631 | list_for_each_entry(chip, &pwm_chips, list) | |
632 | if (chip->dev && chip->dev->of_node == np) { | |
633 | mutex_unlock(&pwm_lock); | |
634 | return chip; | |
635 | } | |
636 | ||
637 | mutex_unlock(&pwm_lock); | |
638 | ||
639 | return ERR_PTR(-EPROBE_DEFER); | |
640 | } | |
641 | ||
642 | /** | |
8eb96127 | 643 | * of_pwm_get() - request a PWM via the PWM framework |
7299ab70 TR |
644 | * @np: device node to get the PWM from |
645 | * @con_id: consumer name | |
646 | * | |
647 | * Returns the PWM device parsed from the phandle and index specified in the | |
648 | * "pwms" property of a device tree node or a negative error-code on failure. | |
649 | * Values parsed from the device tree are stored in the returned PWM device | |
650 | * object. | |
651 | * | |
652 | * If con_id is NULL, the first PWM device listed in the "pwms" property will | |
653 | * be requested. Otherwise the "pwm-names" property is used to do a reverse | |
654 | * lookup of the PWM index. This also means that the "pwm-names" property | |
655 | * becomes mandatory for devices that look up the PWM device via the con_id | |
656 | * parameter. | |
04883802 TR |
657 | * |
658 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
659 | * error code on failure. | |
7299ab70 | 660 | */ |
8eb96127 | 661 | struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) |
7299ab70 TR |
662 | { |
663 | struct pwm_device *pwm = NULL; | |
664 | struct of_phandle_args args; | |
665 | struct pwm_chip *pc; | |
666 | int index = 0; | |
667 | int err; | |
668 | ||
669 | if (con_id) { | |
670 | index = of_property_match_string(np, "pwm-names", con_id); | |
671 | if (index < 0) | |
672 | return ERR_PTR(index); | |
673 | } | |
674 | ||
675 | err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index, | |
676 | &args); | |
677 | if (err) { | |
f2dafc09 | 678 | pr_err("%s(): can't parse \"pwms\" property\n", __func__); |
7299ab70 TR |
679 | return ERR_PTR(err); |
680 | } | |
681 | ||
682 | pc = of_node_to_pwmchip(args.np); | |
683 | if (IS_ERR(pc)) { | |
93c292ef JB |
684 | if (PTR_ERR(pc) != -EPROBE_DEFER) |
685 | pr_err("%s(): PWM chip not found\n", __func__); | |
686 | ||
7299ab70 TR |
687 | pwm = ERR_CAST(pc); |
688 | goto put; | |
689 | } | |
690 | ||
7299ab70 TR |
691 | pwm = pc->of_xlate(pc, &args); |
692 | if (IS_ERR(pwm)) | |
693 | goto put; | |
694 | ||
695 | /* | |
696 | * If a consumer name was not given, try to look it up from the | |
697 | * "pwm-names" property if it exists. Otherwise use the name of | |
698 | * the user device node. | |
699 | */ | |
700 | if (!con_id) { | |
701 | err = of_property_read_string_index(np, "pwm-names", index, | |
702 | &con_id); | |
703 | if (err < 0) | |
704 | con_id = np->name; | |
705 | } | |
706 | ||
707 | pwm->label = con_id; | |
708 | ||
709 | put: | |
710 | of_node_put(args.np); | |
711 | ||
712 | return pwm; | |
713 | } | |
8eb96127 | 714 | EXPORT_SYMBOL_GPL(of_pwm_get); |
7299ab70 | 715 | |
8138d2dd TR |
716 | /** |
717 | * pwm_add_table() - register PWM device consumers | |
718 | * @table: array of consumers to register | |
719 | * @num: number of consumers in table | |
720 | */ | |
c264f111 | 721 | void pwm_add_table(struct pwm_lookup *table, size_t num) |
8138d2dd TR |
722 | { |
723 | mutex_lock(&pwm_lookup_lock); | |
724 | ||
725 | while (num--) { | |
726 | list_add_tail(&table->list, &pwm_lookup_list); | |
727 | table++; | |
728 | } | |
729 | ||
730 | mutex_unlock(&pwm_lookup_lock); | |
731 | } | |
732 | ||
efb0de55 SK |
733 | /** |
734 | * pwm_remove_table() - unregister PWM device consumers | |
735 | * @table: array of consumers to unregister | |
736 | * @num: number of consumers in table | |
737 | */ | |
738 | void pwm_remove_table(struct pwm_lookup *table, size_t num) | |
739 | { | |
740 | mutex_lock(&pwm_lookup_lock); | |
741 | ||
742 | while (num--) { | |
743 | list_del(&table->list); | |
744 | table++; | |
745 | } | |
746 | ||
747 | mutex_unlock(&pwm_lookup_lock); | |
748 | } | |
749 | ||
8138d2dd TR |
750 | /** |
751 | * pwm_get() - look up and request a PWM device | |
752 | * @dev: device for PWM consumer | |
753 | * @con_id: consumer name | |
754 | * | |
7299ab70 TR |
755 | * Lookup is first attempted using DT. If the device was not instantiated from |
756 | * a device tree, a PWM chip and a relative index is looked up via a table | |
757 | * supplied by board setup code (see pwm_add_table()). | |
8138d2dd TR |
758 | * |
759 | * Once a PWM chip has been found the specified PWM device will be requested | |
760 | * and is ready to be used. | |
04883802 TR |
761 | * |
762 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
763 | * error code on failure. | |
8138d2dd TR |
764 | */ |
765 | struct pwm_device *pwm_get(struct device *dev, const char *con_id) | |
766 | { | |
e50d3523 | 767 | const char *dev_id = dev ? dev_name(dev) : NULL; |
69efb343 HG |
768 | struct pwm_device *pwm; |
769 | struct pwm_chip *chip; | |
8138d2dd | 770 | unsigned int best = 0; |
70145f87 | 771 | struct pwm_lookup *p, *chosen = NULL; |
8138d2dd | 772 | unsigned int match; |
b526a314 | 773 | int err; |
8138d2dd | 774 | |
7299ab70 TR |
775 | /* look up via DT first */ |
776 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) | |
8eb96127 | 777 | return of_pwm_get(dev->of_node, con_id); |
7299ab70 | 778 | |
8138d2dd TR |
779 | /* |
780 | * We look up the provider in the static table typically provided by | |
781 | * board setup code. We first try to lookup the consumer device by | |
782 | * name. If the consumer device was passed in as NULL or if no match | |
783 | * was found, we try to find the consumer by directly looking it up | |
784 | * by name. | |
785 | * | |
786 | * If a match is found, the provider PWM chip is looked up by name | |
787 | * and a PWM device is requested using the PWM device per-chip index. | |
788 | * | |
789 | * The lookup algorithm was shamelessly taken from the clock | |
790 | * framework: | |
791 | * | |
792 | * We do slightly fuzzy matching here: | |
793 | * An entry with a NULL ID is assumed to be a wildcard. | |
794 | * If an entry has a device ID, it must match | |
795 | * If an entry has a connection ID, it must match | |
796 | * Then we take the most specific entry - with the following order | |
797 | * of precedence: dev+con > dev only > con only. | |
798 | */ | |
799 | mutex_lock(&pwm_lookup_lock); | |
800 | ||
801 | list_for_each_entry(p, &pwm_lookup_list, list) { | |
802 | match = 0; | |
803 | ||
804 | if (p->dev_id) { | |
805 | if (!dev_id || strcmp(p->dev_id, dev_id)) | |
806 | continue; | |
807 | ||
808 | match += 2; | |
809 | } | |
810 | ||
811 | if (p->con_id) { | |
812 | if (!con_id || strcmp(p->con_id, con_id)) | |
813 | continue; | |
814 | ||
815 | match += 1; | |
816 | } | |
817 | ||
818 | if (match > best) { | |
70145f87 | 819 | chosen = p; |
8138d2dd TR |
820 | |
821 | if (match != 3) | |
822 | best = match; | |
823 | else | |
824 | break; | |
825 | } | |
826 | } | |
827 | ||
69efb343 HG |
828 | mutex_unlock(&pwm_lookup_lock); |
829 | ||
830 | if (!chosen) | |
831 | return ERR_PTR(-ENODEV); | |
3796ce1d | 832 | |
70145f87 | 833 | chip = pwmchip_find_by_name(chosen->provider); |
b526a314 HG |
834 | |
835 | /* | |
836 | * If the lookup entry specifies a module, load the module and retry | |
837 | * the PWM chip lookup. This can be used to work around driver load | |
838 | * ordering issues if driver's can't be made to properly support the | |
839 | * deferred probe mechanism. | |
840 | */ | |
841 | if (!chip && chosen->module) { | |
842 | err = request_module(chosen->module); | |
843 | if (err == 0) | |
844 | chip = pwmchip_find_by_name(chosen->provider); | |
845 | } | |
846 | ||
70145f87 | 847 | if (!chip) |
69efb343 | 848 | return ERR_PTR(-EPROBE_DEFER); |
3796ce1d | 849 | |
70145f87 GU |
850 | pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id); |
851 | if (IS_ERR(pwm)) | |
69efb343 | 852 | return pwm; |
8138d2dd | 853 | |
fbd45a12 BB |
854 | pwm->args.period = chosen->period; |
855 | pwm->args.polarity = chosen->polarity; | |
856 | ||
8138d2dd TR |
857 | return pwm; |
858 | } | |
859 | EXPORT_SYMBOL_GPL(pwm_get); | |
860 | ||
861 | /** | |
862 | * pwm_put() - release a PWM device | |
863 | * @pwm: PWM device | |
864 | */ | |
865 | void pwm_put(struct pwm_device *pwm) | |
866 | { | |
867 | if (!pwm) | |
868 | return; | |
869 | ||
870 | mutex_lock(&pwm_lock); | |
871 | ||
872 | if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) { | |
e50d3523 | 873 | pr_warn("PWM device already freed\n"); |
8138d2dd TR |
874 | goto out; |
875 | } | |
876 | ||
877 | if (pwm->chip->ops->free) | |
878 | pwm->chip->ops->free(pwm->chip, pwm); | |
879 | ||
880 | pwm->label = NULL; | |
881 | ||
882 | module_put(pwm->chip->ops->owner); | |
883 | out: | |
884 | mutex_unlock(&pwm_lock); | |
885 | } | |
886 | EXPORT_SYMBOL_GPL(pwm_put); | |
887 | ||
6354316d AC |
888 | static void devm_pwm_release(struct device *dev, void *res) |
889 | { | |
890 | pwm_put(*(struct pwm_device **)res); | |
891 | } | |
892 | ||
893 | /** | |
894 | * devm_pwm_get() - resource managed pwm_get() | |
895 | * @dev: device for PWM consumer | |
896 | * @con_id: consumer name | |
897 | * | |
898 | * This function performs like pwm_get() but the acquired PWM device will | |
899 | * automatically be released on driver detach. | |
04883802 TR |
900 | * |
901 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
902 | * error code on failure. | |
6354316d AC |
903 | */ |
904 | struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id) | |
905 | { | |
906 | struct pwm_device **ptr, *pwm; | |
907 | ||
77f0b9d2 | 908 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
6354316d AC |
909 | if (!ptr) |
910 | return ERR_PTR(-ENOMEM); | |
911 | ||
912 | pwm = pwm_get(dev, con_id); | |
913 | if (!IS_ERR(pwm)) { | |
914 | *ptr = pwm; | |
915 | devres_add(dev, ptr); | |
916 | } else { | |
917 | devres_free(ptr); | |
918 | } | |
919 | ||
920 | return pwm; | |
921 | } | |
922 | EXPORT_SYMBOL_GPL(devm_pwm_get); | |
923 | ||
261a5edd PU |
924 | /** |
925 | * devm_of_pwm_get() - resource managed of_pwm_get() | |
926 | * @dev: device for PWM consumer | |
927 | * @np: device node to get the PWM from | |
928 | * @con_id: consumer name | |
929 | * | |
930 | * This function performs like of_pwm_get() but the acquired PWM device will | |
931 | * automatically be released on driver detach. | |
04883802 TR |
932 | * |
933 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
934 | * error code on failure. | |
261a5edd PU |
935 | */ |
936 | struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, | |
937 | const char *con_id) | |
938 | { | |
939 | struct pwm_device **ptr, *pwm; | |
940 | ||
77f0b9d2 | 941 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
261a5edd PU |
942 | if (!ptr) |
943 | return ERR_PTR(-ENOMEM); | |
944 | ||
945 | pwm = of_pwm_get(np, con_id); | |
946 | if (!IS_ERR(pwm)) { | |
947 | *ptr = pwm; | |
948 | devres_add(dev, ptr); | |
949 | } else { | |
950 | devres_free(ptr); | |
951 | } | |
952 | ||
953 | return pwm; | |
954 | } | |
955 | EXPORT_SYMBOL_GPL(devm_of_pwm_get); | |
956 | ||
6354316d AC |
957 | static int devm_pwm_match(struct device *dev, void *res, void *data) |
958 | { | |
959 | struct pwm_device **p = res; | |
960 | ||
961 | if (WARN_ON(!p || !*p)) | |
962 | return 0; | |
963 | ||
964 | return *p == data; | |
965 | } | |
966 | ||
967 | /** | |
968 | * devm_pwm_put() - resource managed pwm_put() | |
969 | * @dev: device for PWM consumer | |
970 | * @pwm: PWM device | |
971 | * | |
972 | * Release a PWM previously allocated using devm_pwm_get(). Calling this | |
973 | * function is usually not needed because devm-allocated resources are | |
974 | * automatically released on driver detach. | |
975 | */ | |
976 | void devm_pwm_put(struct device *dev, struct pwm_device *pwm) | |
977 | { | |
978 | WARN_ON(devres_release(dev, devm_pwm_release, devm_pwm_match, pwm)); | |
979 | } | |
980 | EXPORT_SYMBOL_GPL(devm_pwm_put); | |
981 | ||
62099abf TR |
982 | #ifdef CONFIG_DEBUG_FS |
983 | static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) | |
984 | { | |
985 | unsigned int i; | |
986 | ||
987 | for (i = 0; i < chip->npwm; i++) { | |
988 | struct pwm_device *pwm = &chip->pwms[i]; | |
39100cee BB |
989 | struct pwm_state state; |
990 | ||
991 | pwm_get_state(pwm, &state); | |
62099abf TR |
992 | |
993 | seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label); | |
994 | ||
995 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) | |
adcba1e3 | 996 | seq_puts(s, " requested"); |
62099abf | 997 | |
39100cee | 998 | if (state.enabled) |
adcba1e3 | 999 | seq_puts(s, " enabled"); |
62099abf | 1000 | |
23e3523f HS |
1001 | seq_printf(s, " period: %u ns", state.period); |
1002 | seq_printf(s, " duty: %u ns", state.duty_cycle); | |
1003 | seq_printf(s, " polarity: %s", | |
1004 | state.polarity ? "inverse" : "normal"); | |
1005 | ||
adcba1e3 | 1006 | seq_puts(s, "\n"); |
62099abf TR |
1007 | } |
1008 | } | |
1009 | ||
1010 | static void *pwm_seq_start(struct seq_file *s, loff_t *pos) | |
1011 | { | |
1012 | mutex_lock(&pwm_lock); | |
1013 | s->private = ""; | |
1014 | ||
1015 | return seq_list_start(&pwm_chips, *pos); | |
1016 | } | |
1017 | ||
1018 | static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
1019 | { | |
1020 | s->private = "\n"; | |
1021 | ||
1022 | return seq_list_next(v, &pwm_chips, pos); | |
1023 | } | |
1024 | ||
1025 | static void pwm_seq_stop(struct seq_file *s, void *v) | |
1026 | { | |
1027 | mutex_unlock(&pwm_lock); | |
1028 | } | |
1029 | ||
1030 | static int pwm_seq_show(struct seq_file *s, void *v) | |
1031 | { | |
1032 | struct pwm_chip *chip = list_entry(v, struct pwm_chip, list); | |
1033 | ||
1034 | seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private, | |
1035 | chip->dev->bus ? chip->dev->bus->name : "no-bus", | |
1036 | dev_name(chip->dev), chip->npwm, | |
1037 | (chip->npwm != 1) ? "s" : ""); | |
1038 | ||
cc2d2247 | 1039 | pwm_dbg_show(chip, s); |
62099abf TR |
1040 | |
1041 | return 0; | |
1042 | } | |
1043 | ||
1044 | static const struct seq_operations pwm_seq_ops = { | |
1045 | .start = pwm_seq_start, | |
1046 | .next = pwm_seq_next, | |
1047 | .stop = pwm_seq_stop, | |
1048 | .show = pwm_seq_show, | |
1049 | }; | |
1050 | ||
1051 | static int pwm_seq_open(struct inode *inode, struct file *file) | |
1052 | { | |
1053 | return seq_open(file, &pwm_seq_ops); | |
1054 | } | |
1055 | ||
1056 | static const struct file_operations pwm_debugfs_ops = { | |
1057 | .owner = THIS_MODULE, | |
1058 | .open = pwm_seq_open, | |
1059 | .read = seq_read, | |
1060 | .llseek = seq_lseek, | |
1061 | .release = seq_release, | |
1062 | }; | |
1063 | ||
1064 | static int __init pwm_debugfs_init(void) | |
1065 | { | |
1066 | debugfs_create_file("pwm", S_IFREG | S_IRUGO, NULL, NULL, | |
1067 | &pwm_debugfs_ops); | |
1068 | ||
1069 | return 0; | |
1070 | } | |
62099abf TR |
1071 | subsys_initcall(pwm_debugfs_init); |
1072 | #endif /* CONFIG_DEBUG_FS */ |