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]; | |
78 | radix_tree_delete(&pwm_tree, pwm->pwm); | |
0c2498f1 SH |
79 | } |
80 | ||
f051c466 TR |
81 | bitmap_clear(allocated_pwms, chip->base, chip->npwm); |
82 | ||
83 | kfree(chip->pwms); | |
84 | chip->pwms = NULL; | |
85 | } | |
86 | ||
8138d2dd TR |
87 | static struct pwm_chip *pwmchip_find_by_name(const char *name) |
88 | { | |
89 | struct pwm_chip *chip; | |
90 | ||
91 | if (!name) | |
92 | return NULL; | |
93 | ||
94 | mutex_lock(&pwm_lock); | |
95 | ||
96 | list_for_each_entry(chip, &pwm_chips, list) { | |
97 | const char *chip_name = dev_name(chip->dev); | |
98 | ||
99 | if (chip_name && strcmp(chip_name, name) == 0) { | |
100 | mutex_unlock(&pwm_lock); | |
101 | return chip; | |
102 | } | |
103 | } | |
104 | ||
105 | mutex_unlock(&pwm_lock); | |
106 | ||
107 | return NULL; | |
108 | } | |
109 | ||
f051c466 TR |
110 | static int pwm_device_request(struct pwm_device *pwm, const char *label) |
111 | { | |
112 | int err; | |
113 | ||
114 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) | |
115 | return -EBUSY; | |
116 | ||
117 | if (!try_module_get(pwm->chip->ops->owner)) | |
118 | return -ENODEV; | |
119 | ||
120 | if (pwm->chip->ops->request) { | |
121 | err = pwm->chip->ops->request(pwm->chip, pwm); | |
122 | if (err) { | |
123 | module_put(pwm->chip->ops->owner); | |
124 | return err; | |
125 | } | |
126 | } | |
127 | ||
128 | set_bit(PWMF_REQUESTED, &pwm->flags); | |
129 | pwm->label = label; | |
130 | ||
e39c0df1 BB |
131 | /* |
132 | * FIXME: This should be removed once all PWM users properly make use | |
133 | * of struct pwm_args to initialize the PWM device. As long as this is | |
134 | * here, the PWM state and hardware state can get out of sync. | |
135 | */ | |
136 | pwm_apply_args(pwm); | |
137 | ||
f051c466 TR |
138 | return 0; |
139 | } | |
140 | ||
83af2402 PA |
141 | struct pwm_device * |
142 | of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args) | |
143 | { | |
144 | struct pwm_device *pwm; | |
145 | ||
146 | if (pc->of_pwm_n_cells < 3) | |
147 | return ERR_PTR(-EINVAL); | |
148 | ||
149 | if (args->args[0] >= pc->npwm) | |
150 | return ERR_PTR(-EINVAL); | |
151 | ||
152 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); | |
153 | if (IS_ERR(pwm)) | |
154 | return pwm; | |
155 | ||
e39c0df1 | 156 | pwm->args.period = args->args[1]; |
83af2402 | 157 | |
208be769 | 158 | if (args->args[2] & PWM_POLARITY_INVERTED) |
e39c0df1 | 159 | pwm->args.polarity = PWM_POLARITY_INVERSED; |
83af2402 | 160 | else |
e39c0df1 | 161 | pwm->args.polarity = PWM_POLARITY_NORMAL; |
83af2402 PA |
162 | |
163 | return pwm; | |
164 | } | |
417328c3 | 165 | EXPORT_SYMBOL_GPL(of_pwm_xlate_with_flags); |
83af2402 | 166 | |
e50d3523 SK |
167 | static struct pwm_device * |
168 | of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args) | |
7299ab70 TR |
169 | { |
170 | struct pwm_device *pwm; | |
171 | ||
172 | if (pc->of_pwm_n_cells < 2) | |
173 | return ERR_PTR(-EINVAL); | |
174 | ||
175 | if (args->args[0] >= pc->npwm) | |
176 | return ERR_PTR(-EINVAL); | |
177 | ||
178 | pwm = pwm_request_from_chip(pc, args->args[0], NULL); | |
179 | if (IS_ERR(pwm)) | |
180 | return pwm; | |
181 | ||
e39c0df1 | 182 | pwm->args.period = args->args[1]; |
7299ab70 TR |
183 | |
184 | return pwm; | |
185 | } | |
186 | ||
dfeb86ec | 187 | static void of_pwmchip_add(struct pwm_chip *chip) |
7299ab70 TR |
188 | { |
189 | if (!chip->dev || !chip->dev->of_node) | |
190 | return; | |
191 | ||
192 | if (!chip->of_xlate) { | |
193 | chip->of_xlate = of_pwm_simple_xlate; | |
194 | chip->of_pwm_n_cells = 2; | |
195 | } | |
196 | ||
197 | of_node_get(chip->dev->of_node); | |
198 | } | |
199 | ||
dfeb86ec | 200 | static void of_pwmchip_remove(struct pwm_chip *chip) |
7299ab70 | 201 | { |
8d6cc073 | 202 | if (chip->dev) |
7299ab70 TR |
203 | of_node_put(chip->dev->of_node); |
204 | } | |
205 | ||
f051c466 TR |
206 | /** |
207 | * pwm_set_chip_data() - set private chip data for a PWM | |
208 | * @pwm: PWM device | |
209 | * @data: pointer to chip-specific data | |
04883802 TR |
210 | * |
211 | * Returns: 0 on success or a negative error code on failure. | |
f051c466 TR |
212 | */ |
213 | int pwm_set_chip_data(struct pwm_device *pwm, void *data) | |
214 | { | |
215 | if (!pwm) | |
216 | return -EINVAL; | |
217 | ||
218 | pwm->chip_data = data; | |
219 | ||
220 | return 0; | |
221 | } | |
928c4477 | 222 | EXPORT_SYMBOL_GPL(pwm_set_chip_data); |
f051c466 TR |
223 | |
224 | /** | |
225 | * pwm_get_chip_data() - get private chip data for a PWM | |
226 | * @pwm: PWM device | |
04883802 TR |
227 | * |
228 | * Returns: A pointer to the chip-private data for the PWM device. | |
f051c466 TR |
229 | */ |
230 | void *pwm_get_chip_data(struct pwm_device *pwm) | |
231 | { | |
232 | return pwm ? pwm->chip_data : NULL; | |
0c2498f1 | 233 | } |
928c4477 | 234 | EXPORT_SYMBOL_GPL(pwm_get_chip_data); |
0c2498f1 SH |
235 | |
236 | /** | |
b6a00fae | 237 | * pwmchip_add_with_polarity() - register a new PWM chip |
0c2498f1 | 238 | * @chip: the PWM chip to add |
b6a00fae | 239 | * @polarity: initial polarity of PWM channels |
f051c466 TR |
240 | * |
241 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base | |
b6a00fae TK |
242 | * will be used. The initial polarity for all channels is specified by the |
243 | * @polarity parameter. | |
04883802 TR |
244 | * |
245 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 | 246 | */ |
b6a00fae TK |
247 | int pwmchip_add_with_polarity(struct pwm_chip *chip, |
248 | enum pwm_polarity polarity) | |
0c2498f1 SH |
249 | { |
250 | struct pwm_device *pwm; | |
f051c466 TR |
251 | unsigned int i; |
252 | int ret; | |
0c2498f1 | 253 | |
f051c466 | 254 | if (!chip || !chip->dev || !chip->ops || !chip->ops->config || |
533acc0e | 255 | !chip->ops->enable || !chip->ops->disable || !chip->npwm) |
f051c466 | 256 | return -EINVAL; |
0c2498f1 SH |
257 | |
258 | mutex_lock(&pwm_lock); | |
259 | ||
f051c466 TR |
260 | ret = alloc_pwms(chip->base, chip->npwm); |
261 | if (ret < 0) | |
262 | goto out; | |
263 | ||
264 | chip->pwms = kzalloc(chip->npwm * sizeof(*pwm), GFP_KERNEL); | |
265 | if (!chip->pwms) { | |
266 | ret = -ENOMEM; | |
0c2498f1 SH |
267 | goto out; |
268 | } | |
269 | ||
f051c466 TR |
270 | chip->base = ret; |
271 | ||
272 | for (i = 0; i < chip->npwm; i++) { | |
273 | pwm = &chip->pwms[i]; | |
274 | ||
275 | pwm->chip = chip; | |
276 | pwm->pwm = chip->base + i; | |
277 | pwm->hwpwm = i; | |
b6a00fae | 278 | pwm->polarity = polarity; |
d1cd2142 | 279 | mutex_init(&pwm->lock); |
0c2498f1 | 280 | |
f051c466 TR |
281 | radix_tree_insert(&pwm_tree, pwm->pwm, pwm); |
282 | } | |
283 | ||
284 | bitmap_set(allocated_pwms, chip->base, chip->npwm); | |
285 | ||
286 | INIT_LIST_HEAD(&chip->list); | |
287 | list_add(&chip->list, &pwm_chips); | |
0c2498f1 | 288 | |
f051c466 TR |
289 | ret = 0; |
290 | ||
7299ab70 TR |
291 | if (IS_ENABLED(CONFIG_OF)) |
292 | of_pwmchip_add(chip); | |
293 | ||
76abbdde HS |
294 | pwmchip_sysfs_export(chip); |
295 | ||
f051c466 TR |
296 | out: |
297 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
298 | return ret; |
299 | } | |
b6a00fae TK |
300 | EXPORT_SYMBOL_GPL(pwmchip_add_with_polarity); |
301 | ||
302 | /** | |
303 | * pwmchip_add() - register a new PWM chip | |
304 | * @chip: the PWM chip to add | |
305 | * | |
306 | * Register a new PWM chip. If chip->base < 0 then a dynamically assigned base | |
307 | * will be used. The initial polarity for all channels is normal. | |
04883802 TR |
308 | * |
309 | * Returns: 0 on success or a negative error code on failure. | |
b6a00fae TK |
310 | */ |
311 | int pwmchip_add(struct pwm_chip *chip) | |
312 | { | |
313 | return pwmchip_add_with_polarity(chip, PWM_POLARITY_NORMAL); | |
314 | } | |
0c2498f1 SH |
315 | EXPORT_SYMBOL_GPL(pwmchip_add); |
316 | ||
317 | /** | |
318 | * pwmchip_remove() - remove a PWM chip | |
319 | * @chip: the PWM chip to remove | |
320 | * | |
321 | * Removes a PWM chip. This function may return busy if the PWM chip provides | |
322 | * a PWM device that is still requested. | |
04883802 TR |
323 | * |
324 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 SH |
325 | */ |
326 | int pwmchip_remove(struct pwm_chip *chip) | |
327 | { | |
f051c466 | 328 | unsigned int i; |
0c2498f1 SH |
329 | int ret = 0; |
330 | ||
331 | mutex_lock(&pwm_lock); | |
332 | ||
f051c466 TR |
333 | for (i = 0; i < chip->npwm; i++) { |
334 | struct pwm_device *pwm = &chip->pwms[i]; | |
0c2498f1 | 335 | |
f051c466 TR |
336 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) { |
337 | ret = -EBUSY; | |
338 | goto out; | |
339 | } | |
0c2498f1 SH |
340 | } |
341 | ||
f051c466 | 342 | list_del_init(&chip->list); |
7299ab70 TR |
343 | |
344 | if (IS_ENABLED(CONFIG_OF)) | |
345 | of_pwmchip_remove(chip); | |
346 | ||
f051c466 | 347 | free_pwms(chip); |
0c2498f1 | 348 | |
76abbdde HS |
349 | pwmchip_sysfs_unexport(chip); |
350 | ||
0c2498f1 SH |
351 | out: |
352 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
353 | return ret; |
354 | } | |
355 | EXPORT_SYMBOL_GPL(pwmchip_remove); | |
356 | ||
357 | /** | |
358 | * pwm_request() - request a PWM device | |
04883802 | 359 | * @pwm: global PWM device index |
0c2498f1 | 360 | * @label: PWM device label |
8138d2dd TR |
361 | * |
362 | * This function is deprecated, use pwm_get() instead. | |
04883802 TR |
363 | * |
364 | * Returns: A pointer to a PWM device or an ERR_PTR()-encoded error code on | |
365 | * failure. | |
0c2498f1 | 366 | */ |
f051c466 | 367 | struct pwm_device *pwm_request(int pwm, const char *label) |
0c2498f1 | 368 | { |
f051c466 TR |
369 | struct pwm_device *dev; |
370 | int err; | |
371 | ||
372 | if (pwm < 0 || pwm >= MAX_PWMS) | |
373 | return ERR_PTR(-EINVAL); | |
0c2498f1 SH |
374 | |
375 | mutex_lock(&pwm_lock); | |
376 | ||
f051c466 TR |
377 | dev = pwm_to_device(pwm); |
378 | if (!dev) { | |
379 | dev = ERR_PTR(-EPROBE_DEFER); | |
0c2498f1 SH |
380 | goto out; |
381 | } | |
382 | ||
f051c466 TR |
383 | err = pwm_device_request(dev, label); |
384 | if (err < 0) | |
385 | dev = ERR_PTR(err); | |
0c2498f1 | 386 | |
f051c466 TR |
387 | out: |
388 | mutex_unlock(&pwm_lock); | |
0c2498f1 | 389 | |
f051c466 TR |
390 | return dev; |
391 | } | |
392 | EXPORT_SYMBOL_GPL(pwm_request); | |
0c2498f1 | 393 | |
f051c466 TR |
394 | /** |
395 | * pwm_request_from_chip() - request a PWM device relative to a PWM chip | |
396 | * @chip: PWM chip | |
397 | * @index: per-chip index of the PWM to request | |
398 | * @label: a literal description string of this PWM | |
399 | * | |
04883802 TR |
400 | * Returns: A pointer to the PWM device at the given index of the given PWM |
401 | * chip. A negative error code is returned if the index is not valid for the | |
402 | * specified PWM chip or if the PWM device cannot be requested. | |
f051c466 TR |
403 | */ |
404 | struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, | |
405 | unsigned int index, | |
406 | const char *label) | |
407 | { | |
408 | struct pwm_device *pwm; | |
409 | int err; | |
0c2498f1 | 410 | |
f051c466 TR |
411 | if (!chip || index >= chip->npwm) |
412 | return ERR_PTR(-EINVAL); | |
0c2498f1 | 413 | |
f051c466 TR |
414 | mutex_lock(&pwm_lock); |
415 | pwm = &chip->pwms[index]; | |
0c2498f1 | 416 | |
f051c466 TR |
417 | err = pwm_device_request(pwm, label); |
418 | if (err < 0) | |
419 | pwm = ERR_PTR(err); | |
420 | ||
421 | mutex_unlock(&pwm_lock); | |
0c2498f1 SH |
422 | return pwm; |
423 | } | |
f051c466 | 424 | EXPORT_SYMBOL_GPL(pwm_request_from_chip); |
0c2498f1 SH |
425 | |
426 | /** | |
427 | * pwm_free() - free a PWM device | |
428 | * @pwm: PWM device | |
8138d2dd TR |
429 | * |
430 | * This function is deprecated, use pwm_put() instead. | |
0c2498f1 SH |
431 | */ |
432 | void pwm_free(struct pwm_device *pwm) | |
433 | { | |
8138d2dd | 434 | pwm_put(pwm); |
0c2498f1 SH |
435 | } |
436 | EXPORT_SYMBOL_GPL(pwm_free); | |
437 | ||
438 | /** | |
439 | * pwm_config() - change a PWM device configuration | |
440 | * @pwm: PWM device | |
441 | * @duty_ns: "on" time (in nanoseconds) | |
442 | * @period_ns: duration (in nanoseconds) of one cycle | |
04883802 TR |
443 | * |
444 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 SH |
445 | */ |
446 | int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) | |
447 | { | |
76abbdde HS |
448 | int err; |
449 | ||
c2d476a9 | 450 | if (!pwm || duty_ns < 0 || period_ns <= 0 || duty_ns > period_ns) |
f051c466 TR |
451 | return -EINVAL; |
452 | ||
76abbdde HS |
453 | err = pwm->chip->ops->config(pwm->chip, pwm, duty_ns, period_ns); |
454 | if (err) | |
455 | return err; | |
456 | ||
457 | pwm->duty_cycle = duty_ns; | |
458 | pwm->period = period_ns; | |
459 | ||
460 | return 0; | |
0c2498f1 SH |
461 | } |
462 | EXPORT_SYMBOL_GPL(pwm_config); | |
463 | ||
0aa0869c PA |
464 | /** |
465 | * pwm_set_polarity() - configure the polarity of a PWM signal | |
466 | * @pwm: PWM device | |
467 | * @polarity: new polarity of the PWM signal | |
468 | * | |
04883802 TR |
469 | * Note that the polarity cannot be configured while the PWM device is |
470 | * enabled. | |
471 | * | |
472 | * Returns: 0 on success or a negative error code on failure. | |
0aa0869c PA |
473 | */ |
474 | int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity) | |
475 | { | |
76abbdde HS |
476 | int err; |
477 | ||
0aa0869c PA |
478 | if (!pwm || !pwm->chip->ops) |
479 | return -EINVAL; | |
480 | ||
481 | if (!pwm->chip->ops->set_polarity) | |
482 | return -ENOSYS; | |
483 | ||
d1cd2142 JR |
484 | mutex_lock(&pwm->lock); |
485 | ||
486 | if (pwm_is_enabled(pwm)) { | |
487 | err = -EBUSY; | |
488 | goto unlock; | |
489 | } | |
0aa0869c | 490 | |
76abbdde HS |
491 | err = pwm->chip->ops->set_polarity(pwm->chip, pwm, polarity); |
492 | if (err) | |
d1cd2142 | 493 | goto unlock; |
76abbdde HS |
494 | |
495 | pwm->polarity = polarity; | |
496 | ||
d1cd2142 JR |
497 | unlock: |
498 | mutex_unlock(&pwm->lock); | |
499 | return err; | |
0aa0869c PA |
500 | } |
501 | EXPORT_SYMBOL_GPL(pwm_set_polarity); | |
502 | ||
0c2498f1 SH |
503 | /** |
504 | * pwm_enable() - start a PWM output toggling | |
505 | * @pwm: PWM device | |
04883802 TR |
506 | * |
507 | * Returns: 0 on success or a negative error code on failure. | |
0c2498f1 SH |
508 | */ |
509 | int pwm_enable(struct pwm_device *pwm) | |
510 | { | |
d1cd2142 JR |
511 | int err = 0; |
512 | ||
513 | if (!pwm) | |
514 | return -EINVAL; | |
515 | ||
516 | mutex_lock(&pwm->lock); | |
517 | ||
518 | if (!test_and_set_bit(PWMF_ENABLED, &pwm->flags)) { | |
519 | err = pwm->chip->ops->enable(pwm->chip, pwm); | |
520 | if (err) | |
521 | clear_bit(PWMF_ENABLED, &pwm->flags); | |
522 | } | |
523 | ||
524 | mutex_unlock(&pwm->lock); | |
0c2498f1 | 525 | |
d1cd2142 | 526 | return err; |
0c2498f1 SH |
527 | } |
528 | EXPORT_SYMBOL_GPL(pwm_enable); | |
529 | ||
530 | /** | |
531 | * pwm_disable() - stop a PWM output toggling | |
532 | * @pwm: PWM device | |
533 | */ | |
534 | void pwm_disable(struct pwm_device *pwm) | |
535 | { | |
f051c466 TR |
536 | if (pwm && test_and_clear_bit(PWMF_ENABLED, &pwm->flags)) |
537 | pwm->chip->ops->disable(pwm->chip, pwm); | |
0c2498f1 SH |
538 | } |
539 | EXPORT_SYMBOL_GPL(pwm_disable); | |
62099abf | 540 | |
7299ab70 TR |
541 | static struct pwm_chip *of_node_to_pwmchip(struct device_node *np) |
542 | { | |
543 | struct pwm_chip *chip; | |
544 | ||
545 | mutex_lock(&pwm_lock); | |
546 | ||
547 | list_for_each_entry(chip, &pwm_chips, list) | |
548 | if (chip->dev && chip->dev->of_node == np) { | |
549 | mutex_unlock(&pwm_lock); | |
550 | return chip; | |
551 | } | |
552 | ||
553 | mutex_unlock(&pwm_lock); | |
554 | ||
555 | return ERR_PTR(-EPROBE_DEFER); | |
556 | } | |
557 | ||
558 | /** | |
8eb96127 | 559 | * of_pwm_get() - request a PWM via the PWM framework |
7299ab70 TR |
560 | * @np: device node to get the PWM from |
561 | * @con_id: consumer name | |
562 | * | |
563 | * Returns the PWM device parsed from the phandle and index specified in the | |
564 | * "pwms" property of a device tree node or a negative error-code on failure. | |
565 | * Values parsed from the device tree are stored in the returned PWM device | |
566 | * object. | |
567 | * | |
568 | * If con_id is NULL, the first PWM device listed in the "pwms" property will | |
569 | * be requested. Otherwise the "pwm-names" property is used to do a reverse | |
570 | * lookup of the PWM index. This also means that the "pwm-names" property | |
571 | * becomes mandatory for devices that look up the PWM device via the con_id | |
572 | * parameter. | |
04883802 TR |
573 | * |
574 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
575 | * error code on failure. | |
7299ab70 | 576 | */ |
8eb96127 | 577 | struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id) |
7299ab70 TR |
578 | { |
579 | struct pwm_device *pwm = NULL; | |
580 | struct of_phandle_args args; | |
581 | struct pwm_chip *pc; | |
582 | int index = 0; | |
583 | int err; | |
584 | ||
585 | if (con_id) { | |
586 | index = of_property_match_string(np, "pwm-names", con_id); | |
587 | if (index < 0) | |
588 | return ERR_PTR(index); | |
589 | } | |
590 | ||
591 | err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index, | |
592 | &args); | |
593 | if (err) { | |
594 | pr_debug("%s(): can't parse \"pwms\" property\n", __func__); | |
595 | return ERR_PTR(err); | |
596 | } | |
597 | ||
598 | pc = of_node_to_pwmchip(args.np); | |
599 | if (IS_ERR(pc)) { | |
600 | pr_debug("%s(): PWM chip not found\n", __func__); | |
601 | pwm = ERR_CAST(pc); | |
602 | goto put; | |
603 | } | |
604 | ||
605 | if (args.args_count != pc->of_pwm_n_cells) { | |
606 | pr_debug("%s: wrong #pwm-cells for %s\n", np->full_name, | |
607 | args.np->full_name); | |
608 | pwm = ERR_PTR(-EINVAL); | |
609 | goto put; | |
610 | } | |
611 | ||
612 | pwm = pc->of_xlate(pc, &args); | |
613 | if (IS_ERR(pwm)) | |
614 | goto put; | |
615 | ||
616 | /* | |
617 | * If a consumer name was not given, try to look it up from the | |
618 | * "pwm-names" property if it exists. Otherwise use the name of | |
619 | * the user device node. | |
620 | */ | |
621 | if (!con_id) { | |
622 | err = of_property_read_string_index(np, "pwm-names", index, | |
623 | &con_id); | |
624 | if (err < 0) | |
625 | con_id = np->name; | |
626 | } | |
627 | ||
628 | pwm->label = con_id; | |
629 | ||
630 | put: | |
631 | of_node_put(args.np); | |
632 | ||
633 | return pwm; | |
634 | } | |
8eb96127 | 635 | EXPORT_SYMBOL_GPL(of_pwm_get); |
7299ab70 | 636 | |
8138d2dd TR |
637 | /** |
638 | * pwm_add_table() - register PWM device consumers | |
639 | * @table: array of consumers to register | |
640 | * @num: number of consumers in table | |
641 | */ | |
c264f111 | 642 | void pwm_add_table(struct pwm_lookup *table, size_t num) |
8138d2dd TR |
643 | { |
644 | mutex_lock(&pwm_lookup_lock); | |
645 | ||
646 | while (num--) { | |
647 | list_add_tail(&table->list, &pwm_lookup_list); | |
648 | table++; | |
649 | } | |
650 | ||
651 | mutex_unlock(&pwm_lookup_lock); | |
652 | } | |
653 | ||
efb0de55 SK |
654 | /** |
655 | * pwm_remove_table() - unregister PWM device consumers | |
656 | * @table: array of consumers to unregister | |
657 | * @num: number of consumers in table | |
658 | */ | |
659 | void pwm_remove_table(struct pwm_lookup *table, size_t num) | |
660 | { | |
661 | mutex_lock(&pwm_lookup_lock); | |
662 | ||
663 | while (num--) { | |
664 | list_del(&table->list); | |
665 | table++; | |
666 | } | |
667 | ||
668 | mutex_unlock(&pwm_lookup_lock); | |
669 | } | |
670 | ||
8138d2dd TR |
671 | /** |
672 | * pwm_get() - look up and request a PWM device | |
673 | * @dev: device for PWM consumer | |
674 | * @con_id: consumer name | |
675 | * | |
7299ab70 TR |
676 | * Lookup is first attempted using DT. If the device was not instantiated from |
677 | * a device tree, a PWM chip and a relative index is looked up via a table | |
678 | * supplied by board setup code (see pwm_add_table()). | |
8138d2dd TR |
679 | * |
680 | * Once a PWM chip has been found the specified PWM device will be requested | |
681 | * and is ready to be used. | |
04883802 TR |
682 | * |
683 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
684 | * error code on failure. | |
8138d2dd TR |
685 | */ |
686 | struct pwm_device *pwm_get(struct device *dev, const char *con_id) | |
687 | { | |
688 | struct pwm_device *pwm = ERR_PTR(-EPROBE_DEFER); | |
e50d3523 | 689 | const char *dev_id = dev ? dev_name(dev) : NULL; |
8138d2dd TR |
690 | struct pwm_chip *chip = NULL; |
691 | unsigned int best = 0; | |
70145f87 | 692 | struct pwm_lookup *p, *chosen = NULL; |
8138d2dd TR |
693 | unsigned int match; |
694 | ||
7299ab70 TR |
695 | /* look up via DT first */ |
696 | if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) | |
8eb96127 | 697 | return of_pwm_get(dev->of_node, con_id); |
7299ab70 | 698 | |
8138d2dd TR |
699 | /* |
700 | * We look up the provider in the static table typically provided by | |
701 | * board setup code. We first try to lookup the consumer device by | |
702 | * name. If the consumer device was passed in as NULL or if no match | |
703 | * was found, we try to find the consumer by directly looking it up | |
704 | * by name. | |
705 | * | |
706 | * If a match is found, the provider PWM chip is looked up by name | |
707 | * and a PWM device is requested using the PWM device per-chip index. | |
708 | * | |
709 | * The lookup algorithm was shamelessly taken from the clock | |
710 | * framework: | |
711 | * | |
712 | * We do slightly fuzzy matching here: | |
713 | * An entry with a NULL ID is assumed to be a wildcard. | |
714 | * If an entry has a device ID, it must match | |
715 | * If an entry has a connection ID, it must match | |
716 | * Then we take the most specific entry - with the following order | |
717 | * of precedence: dev+con > dev only > con only. | |
718 | */ | |
719 | mutex_lock(&pwm_lookup_lock); | |
720 | ||
721 | list_for_each_entry(p, &pwm_lookup_list, list) { | |
722 | match = 0; | |
723 | ||
724 | if (p->dev_id) { | |
725 | if (!dev_id || strcmp(p->dev_id, dev_id)) | |
726 | continue; | |
727 | ||
728 | match += 2; | |
729 | } | |
730 | ||
731 | if (p->con_id) { | |
732 | if (!con_id || strcmp(p->con_id, con_id)) | |
733 | continue; | |
734 | ||
735 | match += 1; | |
736 | } | |
737 | ||
738 | if (match > best) { | |
70145f87 | 739 | chosen = p; |
8138d2dd TR |
740 | |
741 | if (match != 3) | |
742 | best = match; | |
743 | else | |
744 | break; | |
745 | } | |
746 | } | |
747 | ||
655a0355 TR |
748 | if (!chosen) { |
749 | pwm = ERR_PTR(-ENODEV); | |
70145f87 | 750 | goto out; |
655a0355 | 751 | } |
3796ce1d | 752 | |
70145f87 GU |
753 | chip = pwmchip_find_by_name(chosen->provider); |
754 | if (!chip) | |
755 | goto out; | |
3796ce1d | 756 | |
e39c0df1 BB |
757 | pwm->args.period = chosen->period; |
758 | pwm->args.polarity = chosen->polarity; | |
759 | ||
70145f87 GU |
760 | pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id); |
761 | if (IS_ERR(pwm)) | |
762 | goto out; | |
8138d2dd | 763 | |
70145f87 GU |
764 | out: |
765 | mutex_unlock(&pwm_lookup_lock); | |
8138d2dd TR |
766 | return pwm; |
767 | } | |
768 | EXPORT_SYMBOL_GPL(pwm_get); | |
769 | ||
770 | /** | |
771 | * pwm_put() - release a PWM device | |
772 | * @pwm: PWM device | |
773 | */ | |
774 | void pwm_put(struct pwm_device *pwm) | |
775 | { | |
776 | if (!pwm) | |
777 | return; | |
778 | ||
779 | mutex_lock(&pwm_lock); | |
780 | ||
781 | if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) { | |
e50d3523 | 782 | pr_warn("PWM device already freed\n"); |
8138d2dd TR |
783 | goto out; |
784 | } | |
785 | ||
786 | if (pwm->chip->ops->free) | |
787 | pwm->chip->ops->free(pwm->chip, pwm); | |
788 | ||
789 | pwm->label = NULL; | |
790 | ||
791 | module_put(pwm->chip->ops->owner); | |
792 | out: | |
793 | mutex_unlock(&pwm_lock); | |
794 | } | |
795 | EXPORT_SYMBOL_GPL(pwm_put); | |
796 | ||
6354316d AC |
797 | static void devm_pwm_release(struct device *dev, void *res) |
798 | { | |
799 | pwm_put(*(struct pwm_device **)res); | |
800 | } | |
801 | ||
802 | /** | |
803 | * devm_pwm_get() - resource managed pwm_get() | |
804 | * @dev: device for PWM consumer | |
805 | * @con_id: consumer name | |
806 | * | |
807 | * This function performs like pwm_get() but the acquired PWM device will | |
808 | * automatically be released on driver detach. | |
04883802 TR |
809 | * |
810 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
811 | * error code on failure. | |
6354316d AC |
812 | */ |
813 | struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id) | |
814 | { | |
815 | struct pwm_device **ptr, *pwm; | |
816 | ||
77f0b9d2 | 817 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
6354316d AC |
818 | if (!ptr) |
819 | return ERR_PTR(-ENOMEM); | |
820 | ||
821 | pwm = pwm_get(dev, con_id); | |
822 | if (!IS_ERR(pwm)) { | |
823 | *ptr = pwm; | |
824 | devres_add(dev, ptr); | |
825 | } else { | |
826 | devres_free(ptr); | |
827 | } | |
828 | ||
829 | return pwm; | |
830 | } | |
831 | EXPORT_SYMBOL_GPL(devm_pwm_get); | |
832 | ||
261a5edd PU |
833 | /** |
834 | * devm_of_pwm_get() - resource managed of_pwm_get() | |
835 | * @dev: device for PWM consumer | |
836 | * @np: device node to get the PWM from | |
837 | * @con_id: consumer name | |
838 | * | |
839 | * This function performs like of_pwm_get() but the acquired PWM device will | |
840 | * automatically be released on driver detach. | |
04883802 TR |
841 | * |
842 | * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded | |
843 | * error code on failure. | |
261a5edd PU |
844 | */ |
845 | struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, | |
846 | const char *con_id) | |
847 | { | |
848 | struct pwm_device **ptr, *pwm; | |
849 | ||
77f0b9d2 | 850 | ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL); |
261a5edd PU |
851 | if (!ptr) |
852 | return ERR_PTR(-ENOMEM); | |
853 | ||
854 | pwm = of_pwm_get(np, con_id); | |
855 | if (!IS_ERR(pwm)) { | |
856 | *ptr = pwm; | |
857 | devres_add(dev, ptr); | |
858 | } else { | |
859 | devres_free(ptr); | |
860 | } | |
861 | ||
862 | return pwm; | |
863 | } | |
864 | EXPORT_SYMBOL_GPL(devm_of_pwm_get); | |
865 | ||
6354316d AC |
866 | static int devm_pwm_match(struct device *dev, void *res, void *data) |
867 | { | |
868 | struct pwm_device **p = res; | |
869 | ||
870 | if (WARN_ON(!p || !*p)) | |
871 | return 0; | |
872 | ||
873 | return *p == data; | |
874 | } | |
875 | ||
876 | /** | |
877 | * devm_pwm_put() - resource managed pwm_put() | |
878 | * @dev: device for PWM consumer | |
879 | * @pwm: PWM device | |
880 | * | |
881 | * Release a PWM previously allocated using devm_pwm_get(). Calling this | |
882 | * function is usually not needed because devm-allocated resources are | |
883 | * automatically released on driver detach. | |
884 | */ | |
885 | void devm_pwm_put(struct device *dev, struct pwm_device *pwm) | |
886 | { | |
887 | WARN_ON(devres_release(dev, devm_pwm_release, devm_pwm_match, pwm)); | |
888 | } | |
889 | EXPORT_SYMBOL_GPL(devm_pwm_put); | |
890 | ||
6e69ab13 FV |
891 | /** |
892 | * pwm_can_sleep() - report whether PWM access will sleep | |
893 | * @pwm: PWM device | |
894 | * | |
04883802 | 895 | * Returns: True if accessing the PWM can sleep, false otherwise. |
6e69ab13 FV |
896 | */ |
897 | bool pwm_can_sleep(struct pwm_device *pwm) | |
898 | { | |
ff01c944 | 899 | return true; |
6e69ab13 FV |
900 | } |
901 | EXPORT_SYMBOL_GPL(pwm_can_sleep); | |
902 | ||
62099abf TR |
903 | #ifdef CONFIG_DEBUG_FS |
904 | static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) | |
905 | { | |
906 | unsigned int i; | |
907 | ||
908 | for (i = 0; i < chip->npwm; i++) { | |
909 | struct pwm_device *pwm = &chip->pwms[i]; | |
910 | ||
911 | seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label); | |
912 | ||
913 | if (test_bit(PWMF_REQUESTED, &pwm->flags)) | |
adcba1e3 | 914 | seq_puts(s, " requested"); |
62099abf | 915 | |
5c31252c | 916 | if (pwm_is_enabled(pwm)) |
adcba1e3 | 917 | seq_puts(s, " enabled"); |
62099abf | 918 | |
adcba1e3 | 919 | seq_puts(s, "\n"); |
62099abf TR |
920 | } |
921 | } | |
922 | ||
923 | static void *pwm_seq_start(struct seq_file *s, loff_t *pos) | |
924 | { | |
925 | mutex_lock(&pwm_lock); | |
926 | s->private = ""; | |
927 | ||
928 | return seq_list_start(&pwm_chips, *pos); | |
929 | } | |
930 | ||
931 | static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos) | |
932 | { | |
933 | s->private = "\n"; | |
934 | ||
935 | return seq_list_next(v, &pwm_chips, pos); | |
936 | } | |
937 | ||
938 | static void pwm_seq_stop(struct seq_file *s, void *v) | |
939 | { | |
940 | mutex_unlock(&pwm_lock); | |
941 | } | |
942 | ||
943 | static int pwm_seq_show(struct seq_file *s, void *v) | |
944 | { | |
945 | struct pwm_chip *chip = list_entry(v, struct pwm_chip, list); | |
946 | ||
947 | seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private, | |
948 | chip->dev->bus ? chip->dev->bus->name : "no-bus", | |
949 | dev_name(chip->dev), chip->npwm, | |
950 | (chip->npwm != 1) ? "s" : ""); | |
951 | ||
952 | if (chip->ops->dbg_show) | |
953 | chip->ops->dbg_show(chip, s); | |
954 | else | |
955 | pwm_dbg_show(chip, s); | |
956 | ||
957 | return 0; | |
958 | } | |
959 | ||
960 | static const struct seq_operations pwm_seq_ops = { | |
961 | .start = pwm_seq_start, | |
962 | .next = pwm_seq_next, | |
963 | .stop = pwm_seq_stop, | |
964 | .show = pwm_seq_show, | |
965 | }; | |
966 | ||
967 | static int pwm_seq_open(struct inode *inode, struct file *file) | |
968 | { | |
969 | return seq_open(file, &pwm_seq_ops); | |
970 | } | |
971 | ||
972 | static const struct file_operations pwm_debugfs_ops = { | |
973 | .owner = THIS_MODULE, | |
974 | .open = pwm_seq_open, | |
975 | .read = seq_read, | |
976 | .llseek = seq_lseek, | |
977 | .release = seq_release, | |
978 | }; | |
979 | ||
980 | static int __init pwm_debugfs_init(void) | |
981 | { | |
982 | debugfs_create_file("pwm", S_IFREG | S_IRUGO, NULL, NULL, | |
983 | &pwm_debugfs_ops); | |
984 | ||
985 | return 0; | |
986 | } | |
62099abf TR |
987 | subsys_initcall(pwm_debugfs_init); |
988 | #endif /* CONFIG_DEBUG_FS */ |