Commit | Line | Data |
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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1a189b97 RK |
2 | #ifndef __LINUX_PWM_H |
3 | #define __LINUX_PWM_H | |
4 | ||
0bcf168b | 5 | #include <linux/err.h> |
d1cd2142 | 6 | #include <linux/mutex.h> |
7299ab70 TR |
7 | #include <linux/of.h> |
8 | ||
3a3d1a4e | 9 | struct pwm_capture; |
62099abf | 10 | struct seq_file; |
3a3d1a4e | 11 | |
0c2498f1 SH |
12 | struct pwm_chip; |
13 | ||
0aa0869c PA |
14 | /** |
15 | * enum pwm_polarity - polarity of a PWM signal | |
16 | * @PWM_POLARITY_NORMAL: a high signal for the duration of the duty- | |
17 | * cycle, followed by a low signal for the remainder of the pulse | |
18 | * period | |
19 | * @PWM_POLARITY_INVERSED: a low signal for the duration of the duty- | |
20 | * cycle, followed by a high signal for the remainder of the pulse | |
21 | * period | |
22 | */ | |
23 | enum pwm_polarity { | |
24 | PWM_POLARITY_NORMAL, | |
25 | PWM_POLARITY_INVERSED, | |
26 | }; | |
27 | ||
e39c0df1 BB |
28 | /** |
29 | * struct pwm_args - board-dependent PWM arguments | |
30 | * @period: reference period | |
31 | * @polarity: reference polarity | |
32 | * | |
33 | * This structure describes board-dependent arguments attached to a PWM | |
34 | * device. These arguments are usually retrieved from the PWM lookup table or | |
35 | * device tree. | |
36 | * | |
37 | * Do not confuse this with the PWM state: PWM arguments represent the initial | |
38 | * configuration that users want to use on this PWM device rather than the | |
39 | * current PWM hardware state. | |
40 | */ | |
41 | struct pwm_args { | |
a9d887dc | 42 | u64 period; |
e39c0df1 BB |
43 | enum pwm_polarity polarity; |
44 | }; | |
45 | ||
f051c466 TR |
46 | enum { |
47 | PWMF_REQUESTED = 1 << 0, | |
09a7e4a3 | 48 | PWMF_EXPORTED = 1 << 1, |
f051c466 TR |
49 | }; |
50 | ||
43a276b0 BB |
51 | /* |
52 | * struct pwm_state - state of a PWM channel | |
53 | * @period: PWM period (in nanoseconds) | |
54 | * @duty_cycle: PWM duty cycle (in nanoseconds) | |
55 | * @polarity: PWM polarity | |
09a7e4a3 | 56 | * @enabled: PWM enabled status |
9e40ee18 CG |
57 | * @usage_power: If set, the PWM driver is only required to maintain the power |
58 | * output but has more freedom regarding signal form. | |
59 | * If supported, the signal can be optimized, for example to | |
60 | * improve EMI by phase shifting individual channels. | |
43a276b0 BB |
61 | */ |
62 | struct pwm_state { | |
a9d887dc GDS |
63 | u64 period; |
64 | u64 duty_cycle; | |
43a276b0 | 65 | enum pwm_polarity polarity; |
09a7e4a3 | 66 | bool enabled; |
9e40ee18 | 67 | bool usage_power; |
43a276b0 BB |
68 | }; |
69 | ||
04883802 TR |
70 | /** |
71 | * struct pwm_device - PWM channel object | |
72 | * @label: name of the PWM device | |
73 | * @flags: flags associated with the PWM device | |
74 | * @hwpwm: per-chip relative index of the PWM device | |
75 | * @pwm: global index of the PWM device | |
76 | * @chip: PWM chip providing this PWM device | |
77 | * @chip_data: chip-private data associated with the PWM device | |
e39c0df1 | 78 | * @args: PWM arguments |
3ad1f3a3 UKK |
79 | * @state: last applied state |
80 | * @last: last implemented state (for PWM_DEBUG) | |
04883802 | 81 | */ |
f051c466 | 82 | struct pwm_device { |
6bc7064a TR |
83 | const char *label; |
84 | unsigned long flags; | |
85 | unsigned int hwpwm; | |
86 | unsigned int pwm; | |
87 | struct pwm_chip *chip; | |
88 | void *chip_data; | |
89 | ||
e39c0df1 | 90 | struct pwm_args args; |
43a276b0 | 91 | struct pwm_state state; |
3ad1f3a3 | 92 | struct pwm_state last; |
f051c466 TR |
93 | }; |
94 | ||
43a276b0 BB |
95 | /** |
96 | * pwm_get_state() - retrieve the current PWM state | |
97 | * @pwm: PWM device | |
98 | * @state: state to fill with the current PWM state | |
1a7a6e80 UKK |
99 | * |
100 | * The returned PWM state represents the state that was applied by a previous call to | |
101 | * pwm_apply_state(). Drivers may have to slightly tweak that state before programming it to | |
102 | * hardware. If pwm_apply_state() was never called, this returns either the current hardware | |
103 | * state (if supported) or the default settings. | |
43a276b0 BB |
104 | */ |
105 | static inline void pwm_get_state(const struct pwm_device *pwm, | |
106 | struct pwm_state *state) | |
107 | { | |
108 | *state = pwm->state; | |
109 | } | |
110 | ||
5c31252c BB |
111 | static inline bool pwm_is_enabled(const struct pwm_device *pwm) |
112 | { | |
09a7e4a3 BB |
113 | struct pwm_state state; |
114 | ||
115 | pwm_get_state(pwm, &state); | |
116 | ||
117 | return state.enabled; | |
5c31252c BB |
118 | } |
119 | ||
a9d887dc | 120 | static inline void pwm_set_period(struct pwm_device *pwm, u64 period) |
f051c466 TR |
121 | { |
122 | if (pwm) | |
43a276b0 | 123 | pwm->state.period = period; |
f051c466 TR |
124 | } |
125 | ||
a9d887dc | 126 | static inline u64 pwm_get_period(const struct pwm_device *pwm) |
f051c466 | 127 | { |
43a276b0 BB |
128 | struct pwm_state state; |
129 | ||
130 | pwm_get_state(pwm, &state); | |
131 | ||
132 | return state.period; | |
f051c466 TR |
133 | } |
134 | ||
76abbdde HS |
135 | static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty) |
136 | { | |
137 | if (pwm) | |
43a276b0 | 138 | pwm->state.duty_cycle = duty; |
76abbdde HS |
139 | } |
140 | ||
a9d887dc | 141 | static inline u64 pwm_get_duty_cycle(const struct pwm_device *pwm) |
76abbdde | 142 | { |
43a276b0 BB |
143 | struct pwm_state state; |
144 | ||
145 | pwm_get_state(pwm, &state); | |
146 | ||
147 | return state.duty_cycle; | |
76abbdde HS |
148 | } |
149 | ||
011e7631 BB |
150 | static inline enum pwm_polarity pwm_get_polarity(const struct pwm_device *pwm) |
151 | { | |
43a276b0 BB |
152 | struct pwm_state state; |
153 | ||
154 | pwm_get_state(pwm, &state); | |
155 | ||
156 | return state.polarity; | |
011e7631 BB |
157 | } |
158 | ||
e39c0df1 BB |
159 | static inline void pwm_get_args(const struct pwm_device *pwm, |
160 | struct pwm_args *args) | |
161 | { | |
162 | *args = pwm->args; | |
163 | } | |
164 | ||
a6a0dbbc BB |
165 | /** |
166 | * pwm_init_state() - prepare a new state to be applied with pwm_apply_state() | |
167 | * @pwm: PWM device | |
168 | * @state: state to fill with the prepared PWM state | |
169 | * | |
170 | * This functions prepares a state that can later be tweaked and applied | |
171 | * to the PWM device with pwm_apply_state(). This is a convenient function | |
172 | * that first retrieves the current PWM state and the replaces the period | |
173 | * and polarity fields with the reference values defined in pwm->args. | |
174 | * Once the function returns, you can adjust the ->enabled and ->duty_cycle | |
175 | * fields according to your needs before calling pwm_apply_state(). | |
176 | * | |
177 | * ->duty_cycle is initially set to zero to avoid cases where the current | |
178 | * ->duty_cycle value exceed the pwm_args->period one, which would trigger | |
179 | * an error if the user calls pwm_apply_state() without adjusting ->duty_cycle | |
180 | * first. | |
181 | */ | |
182 | static inline void pwm_init_state(const struct pwm_device *pwm, | |
183 | struct pwm_state *state) | |
184 | { | |
185 | struct pwm_args args; | |
186 | ||
187 | /* First get the current state. */ | |
188 | pwm_get_state(pwm, state); | |
189 | ||
190 | /* Then fill it with the reference config */ | |
191 | pwm_get_args(pwm, &args); | |
192 | ||
193 | state->period = args.period; | |
194 | state->polarity = args.polarity; | |
195 | state->duty_cycle = 0; | |
9e40ee18 | 196 | state->usage_power = false; |
a6a0dbbc BB |
197 | } |
198 | ||
f6f3bddf BB |
199 | /** |
200 | * pwm_get_relative_duty_cycle() - Get a relative duty cycle value | |
201 | * @state: PWM state to extract the duty cycle from | |
202 | * @scale: target scale of the relative duty cycle | |
203 | * | |
204 | * This functions converts the absolute duty cycle stored in @state (expressed | |
205 | * in nanosecond) into a value relative to the period. | |
206 | * | |
207 | * For example if you want to get the duty_cycle expressed in percent, call: | |
208 | * | |
209 | * pwm_get_state(pwm, &state); | |
210 | * duty = pwm_get_relative_duty_cycle(&state, 100); | |
211 | */ | |
212 | static inline unsigned int | |
213 | pwm_get_relative_duty_cycle(const struct pwm_state *state, unsigned int scale) | |
214 | { | |
215 | if (!state->period) | |
216 | return 0; | |
217 | ||
218 | return DIV_ROUND_CLOSEST_ULL((u64)state->duty_cycle * scale, | |
219 | state->period); | |
220 | } | |
221 | ||
222 | /** | |
223 | * pwm_set_relative_duty_cycle() - Set a relative duty cycle value | |
224 | * @state: PWM state to fill | |
225 | * @duty_cycle: relative duty cycle value | |
226 | * @scale: scale in which @duty_cycle is expressed | |
227 | * | |
228 | * This functions converts a relative into an absolute duty cycle (expressed | |
229 | * in nanoseconds), and puts the result in state->duty_cycle. | |
230 | * | |
231 | * For example if you want to configure a 50% duty cycle, call: | |
232 | * | |
233 | * pwm_init_state(pwm, &state); | |
234 | * pwm_set_relative_duty_cycle(&state, 50, 100); | |
235 | * pwm_apply_state(pwm, &state); | |
236 | * | |
237 | * This functions returns -EINVAL if @duty_cycle and/or @scale are | |
238 | * inconsistent (@scale == 0 or @duty_cycle > @scale). | |
239 | */ | |
240 | static inline int | |
241 | pwm_set_relative_duty_cycle(struct pwm_state *state, unsigned int duty_cycle, | |
242 | unsigned int scale) | |
243 | { | |
244 | if (!scale || duty_cycle > scale) | |
245 | return -EINVAL; | |
246 | ||
247 | state->duty_cycle = DIV_ROUND_CLOSEST_ULL((u64)duty_cycle * | |
248 | state->period, | |
249 | scale); | |
250 | ||
251 | return 0; | |
252 | } | |
253 | ||
0c2498f1 SH |
254 | /** |
255 | * struct pwm_ops - PWM controller operations | |
256 | * @request: optional hook for requesting a PWM | |
257 | * @free: optional hook for freeing a PWM | |
3a3d1a4e | 258 | * @capture: capture and report PWM signal |
27938fd8 | 259 | * @apply: atomically apply a new PWM config |
15fa8a43 BB |
260 | * @get_state: get the current PWM state. This function is only |
261 | * called once per PWM device when the PWM chip is | |
262 | * registered. | |
0c2498f1 | 263 | * @owner: helps prevent removal of modules exporting active PWMs |
5d0a4c11 UKK |
264 | * @config: configure duty cycles and period length for this PWM |
265 | * @set_polarity: configure the polarity of this PWM | |
266 | * @enable: enable PWM output toggling | |
267 | * @disable: disable PWM output toggling | |
0c2498f1 SH |
268 | */ |
269 | struct pwm_ops { | |
6bc7064a TR |
270 | int (*request)(struct pwm_chip *chip, struct pwm_device *pwm); |
271 | void (*free)(struct pwm_chip *chip, struct pwm_device *pwm); | |
3a3d1a4e LJ |
272 | int (*capture)(struct pwm_chip *chip, struct pwm_device *pwm, |
273 | struct pwm_capture *result, unsigned long timeout); | |
5ec803ed | 274 | int (*apply)(struct pwm_chip *chip, struct pwm_device *pwm, |
71523d18 | 275 | const struct pwm_state *state); |
15fa8a43 BB |
276 | void (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm, |
277 | struct pwm_state *state); | |
6bc7064a | 278 | struct module *owner; |
5d0a4c11 UKK |
279 | |
280 | /* Only used by legacy drivers */ | |
281 | int (*config)(struct pwm_chip *chip, struct pwm_device *pwm, | |
282 | int duty_ns, int period_ns); | |
283 | int (*set_polarity)(struct pwm_chip *chip, struct pwm_device *pwm, | |
284 | enum pwm_polarity polarity); | |
285 | int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm); | |
286 | void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm); | |
0c2498f1 SH |
287 | }; |
288 | ||
289 | /** | |
f051c466 TR |
290 | * struct pwm_chip - abstract a PWM controller |
291 | * @dev: device providing the PWMs | |
f051c466 TR |
292 | * @ops: callbacks for this PWM controller |
293 | * @base: number of first PWM controlled by this chip | |
294 | * @npwm: number of PWMs controlled by this chip | |
04883802 TR |
295 | * @of_xlate: request a PWM device given a device tree PWM specifier |
296 | * @of_pwm_n_cells: number of cells expected in the device tree PWM specifier | |
5d0a4c11 UKK |
297 | * @list: list node for internal use |
298 | * @pwms: array of PWM devices allocated by the framework | |
0c2498f1 SH |
299 | */ |
300 | struct pwm_chip { | |
6bc7064a | 301 | struct device *dev; |
6bc7064a TR |
302 | const struct pwm_ops *ops; |
303 | int base; | |
304 | unsigned int npwm; | |
305 | ||
6bc7064a TR |
306 | struct pwm_device * (*of_xlate)(struct pwm_chip *pc, |
307 | const struct of_phandle_args *args); | |
308 | unsigned int of_pwm_n_cells; | |
5d0a4c11 UKK |
309 | |
310 | /* only used internally by the PWM framework */ | |
311 | struct list_head list; | |
312 | struct pwm_device *pwms; | |
0c2498f1 SH |
313 | }; |
314 | ||
3a3d1a4e LJ |
315 | /** |
316 | * struct pwm_capture - PWM capture data | |
317 | * @period: period of the PWM signal (in nanoseconds) | |
318 | * @duty_cycle: duty cycle of the PWM signal (in nanoseconds) | |
319 | */ | |
320 | struct pwm_capture { | |
321 | unsigned int period; | |
322 | unsigned int duty_cycle; | |
323 | }; | |
324 | ||
0bcf168b | 325 | #if IS_ENABLED(CONFIG_PWM) |
5ec803ed BB |
326 | /* PWM user APIs */ |
327 | struct pwm_device *pwm_request(int pwm_id, const char *label); | |
328 | void pwm_free(struct pwm_device *pwm); | |
71523d18 | 329 | int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state); |
5ec803ed BB |
330 | int pwm_adjust_config(struct pwm_device *pwm); |
331 | ||
332 | /** | |
333 | * pwm_config() - change a PWM device configuration | |
334 | * @pwm: PWM device | |
335 | * @duty_ns: "on" time (in nanoseconds) | |
336 | * @period_ns: duration (in nanoseconds) of one cycle | |
337 | * | |
338 | * Returns: 0 on success or a negative error code on failure. | |
339 | */ | |
340 | static inline int pwm_config(struct pwm_device *pwm, int duty_ns, | |
341 | int period_ns) | |
342 | { | |
343 | struct pwm_state state; | |
344 | ||
345 | if (!pwm) | |
346 | return -EINVAL; | |
347 | ||
ef2bf499 BN |
348 | if (duty_ns < 0 || period_ns < 0) |
349 | return -EINVAL; | |
350 | ||
5ec803ed BB |
351 | pwm_get_state(pwm, &state); |
352 | if (state.duty_cycle == duty_ns && state.period == period_ns) | |
353 | return 0; | |
354 | ||
355 | state.duty_cycle = duty_ns; | |
356 | state.period = period_ns; | |
357 | return pwm_apply_state(pwm, &state); | |
358 | } | |
359 | ||
5ec803ed BB |
360 | /** |
361 | * pwm_enable() - start a PWM output toggling | |
362 | * @pwm: PWM device | |
363 | * | |
364 | * Returns: 0 on success or a negative error code on failure. | |
365 | */ | |
366 | static inline int pwm_enable(struct pwm_device *pwm) | |
367 | { | |
368 | struct pwm_state state; | |
369 | ||
370 | if (!pwm) | |
371 | return -EINVAL; | |
372 | ||
373 | pwm_get_state(pwm, &state); | |
374 | if (state.enabled) | |
375 | return 0; | |
376 | ||
377 | state.enabled = true; | |
378 | return pwm_apply_state(pwm, &state); | |
379 | } | |
380 | ||
381 | /** | |
382 | * pwm_disable() - stop a PWM output toggling | |
383 | * @pwm: PWM device | |
384 | */ | |
385 | static inline void pwm_disable(struct pwm_device *pwm) | |
386 | { | |
387 | struct pwm_state state; | |
388 | ||
389 | if (!pwm) | |
390 | return; | |
391 | ||
392 | pwm_get_state(pwm, &state); | |
393 | if (!state.enabled) | |
394 | return; | |
395 | ||
396 | state.enabled = false; | |
397 | pwm_apply_state(pwm, &state); | |
398 | } | |
399 | ||
5ec803ed | 400 | /* PWM provider APIs */ |
3a3d1a4e LJ |
401 | int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result, |
402 | unsigned long timeout); | |
f051c466 TR |
403 | int pwm_set_chip_data(struct pwm_device *pwm, void *data); |
404 | void *pwm_get_chip_data(struct pwm_device *pwm); | |
405 | ||
0c2498f1 SH |
406 | int pwmchip_add(struct pwm_chip *chip); |
407 | int pwmchip_remove(struct pwm_chip *chip); | |
bcda91bf UKK |
408 | |
409 | int devm_pwmchip_add(struct device *dev, struct pwm_chip *chip); | |
410 | ||
f051c466 TR |
411 | struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, |
412 | unsigned int index, | |
413 | const char *label); | |
8138d2dd | 414 | |
83af2402 PA |
415 | struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc, |
416 | const struct of_phandle_args *args); | |
417 | ||
d4c0c470 | 418 | struct pwm_device *pwm_get(struct device *dev, const char *con_id); |
b2c200e3 FG |
419 | struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np, |
420 | const char *con_id); | |
8138d2dd TR |
421 | void pwm_put(struct pwm_device *pwm); |
422 | ||
d4c0c470 | 423 | struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id); |
261a5edd PU |
424 | struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np, |
425 | const char *con_id); | |
4a6ef8e3 NV |
426 | struct pwm_device *devm_fwnode_pwm_get(struct device *dev, |
427 | struct fwnode_handle *fwnode, | |
428 | const char *con_id); | |
0bcf168b | 429 | #else |
5ec803ed BB |
430 | static inline struct pwm_device *pwm_request(int pwm_id, const char *label) |
431 | { | |
432 | return ERR_PTR(-ENODEV); | |
433 | } | |
434 | ||
435 | static inline void pwm_free(struct pwm_device *pwm) | |
436 | { | |
437 | } | |
438 | ||
439 | static inline int pwm_apply_state(struct pwm_device *pwm, | |
440 | const struct pwm_state *state) | |
441 | { | |
442 | return -ENOTSUPP; | |
443 | } | |
444 | ||
445 | static inline int pwm_adjust_config(struct pwm_device *pwm) | |
446 | { | |
447 | return -ENOTSUPP; | |
448 | } | |
449 | ||
450 | static inline int pwm_config(struct pwm_device *pwm, int duty_ns, | |
451 | int period_ns) | |
452 | { | |
453 | return -EINVAL; | |
454 | } | |
455 | ||
3a3d1a4e LJ |
456 | static inline int pwm_capture(struct pwm_device *pwm, |
457 | struct pwm_capture *result, | |
458 | unsigned long timeout) | |
459 | { | |
460 | return -EINVAL; | |
461 | } | |
462 | ||
5ec803ed BB |
463 | static inline int pwm_enable(struct pwm_device *pwm) |
464 | { | |
465 | return -EINVAL; | |
466 | } | |
467 | ||
468 | static inline void pwm_disable(struct pwm_device *pwm) | |
469 | { | |
470 | } | |
471 | ||
0bcf168b TB |
472 | static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data) |
473 | { | |
474 | return -EINVAL; | |
475 | } | |
476 | ||
477 | static inline void *pwm_get_chip_data(struct pwm_device *pwm) | |
478 | { | |
479 | return NULL; | |
480 | } | |
481 | ||
482 | static inline int pwmchip_add(struct pwm_chip *chip) | |
483 | { | |
484 | return -EINVAL; | |
485 | } | |
486 | ||
487 | static inline int pwmchip_remove(struct pwm_chip *chip) | |
488 | { | |
489 | return -EINVAL; | |
490 | } | |
491 | ||
492 | static inline struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip, | |
493 | unsigned int index, | |
494 | const char *label) | |
495 | { | |
496 | return ERR_PTR(-ENODEV); | |
497 | } | |
498 | ||
499 | static inline struct pwm_device *pwm_get(struct device *dev, | |
500 | const char *consumer) | |
501 | { | |
502 | return ERR_PTR(-ENODEV); | |
503 | } | |
504 | ||
b2c200e3 FG |
505 | static inline struct pwm_device *of_pwm_get(struct device *dev, |
506 | struct device_node *np, | |
8eb96127 PU |
507 | const char *con_id) |
508 | { | |
509 | return ERR_PTR(-ENODEV); | |
510 | } | |
511 | ||
0bcf168b TB |
512 | static inline void pwm_put(struct pwm_device *pwm) |
513 | { | |
514 | } | |
515 | ||
516 | static inline struct pwm_device *devm_pwm_get(struct device *dev, | |
517 | const char *consumer) | |
518 | { | |
519 | return ERR_PTR(-ENODEV); | |
520 | } | |
521 | ||
261a5edd PU |
522 | static inline struct pwm_device *devm_of_pwm_get(struct device *dev, |
523 | struct device_node *np, | |
524 | const char *con_id) | |
525 | { | |
526 | return ERR_PTR(-ENODEV); | |
527 | } | |
528 | ||
4a6ef8e3 NV |
529 | static inline struct pwm_device * |
530 | devm_fwnode_pwm_get(struct device *dev, struct fwnode_handle *fwnode, | |
531 | const char *con_id) | |
532 | { | |
533 | return ERR_PTR(-ENODEV); | |
534 | } | |
0bcf168b | 535 | #endif |
6354316d | 536 | |
5ec803ed BB |
537 | static inline void pwm_apply_args(struct pwm_device *pwm) |
538 | { | |
33cdcee0 BB |
539 | struct pwm_state state = { }; |
540 | ||
5ec803ed BB |
541 | /* |
542 | * PWM users calling pwm_apply_args() expect to have a fresh config | |
543 | * where the polarity and period are set according to pwm_args info. | |
544 | * The problem is, polarity can only be changed when the PWM is | |
545 | * disabled. | |
546 | * | |
547 | * PWM drivers supporting hardware readout may declare the PWM device | |
548 | * as enabled, and prevent polarity setting, which changes from the | |
549 | * existing behavior, where all PWM devices are declared as disabled | |
550 | * at startup (even if they are actually enabled), thus authorizing | |
551 | * polarity setting. | |
552 | * | |
33cdcee0 BB |
553 | * To fulfill this requirement, we apply a new state which disables |
554 | * the PWM device and set the reference period and polarity config. | |
5ec803ed BB |
555 | * |
556 | * Note that PWM users requiring a smooth handover between the | |
557 | * bootloader and the kernel (like critical regulators controlled by | |
558 | * PWM devices) will have to switch to the atomic API and avoid calling | |
559 | * pwm_apply_args(). | |
560 | */ | |
33cdcee0 BB |
561 | |
562 | state.enabled = false; | |
563 | state.polarity = pwm->args.polarity; | |
564 | state.period = pwm->args.period; | |
9e40ee18 | 565 | state.usage_power = false; |
33cdcee0 BB |
566 | |
567 | pwm_apply_state(pwm, &state); | |
5ec803ed BB |
568 | } |
569 | ||
8138d2dd TR |
570 | struct pwm_lookup { |
571 | struct list_head list; | |
572 | const char *provider; | |
573 | unsigned int index; | |
574 | const char *dev_id; | |
575 | const char *con_id; | |
3796ce1d AB |
576 | unsigned int period; |
577 | enum pwm_polarity polarity; | |
b526a314 | 578 | const char *module; /* optional, may be NULL */ |
8138d2dd TR |
579 | }; |
580 | ||
b526a314 HG |
581 | #define PWM_LOOKUP_WITH_MODULE(_provider, _index, _dev_id, _con_id, \ |
582 | _period, _polarity, _module) \ | |
583 | { \ | |
584 | .provider = _provider, \ | |
585 | .index = _index, \ | |
586 | .dev_id = _dev_id, \ | |
587 | .con_id = _con_id, \ | |
588 | .period = _period, \ | |
589 | .polarity = _polarity, \ | |
590 | .module = _module, \ | |
8138d2dd TR |
591 | } |
592 | ||
b526a314 HG |
593 | #define PWM_LOOKUP(_provider, _index, _dev_id, _con_id, _period, _polarity) \ |
594 | PWM_LOOKUP_WITH_MODULE(_provider, _index, _dev_id, _con_id, _period, \ | |
595 | _polarity, NULL) | |
596 | ||
0bcf168b | 597 | #if IS_ENABLED(CONFIG_PWM) |
8138d2dd | 598 | void pwm_add_table(struct pwm_lookup *table, size_t num); |
efb0de55 | 599 | void pwm_remove_table(struct pwm_lookup *table, size_t num); |
0bcf168b TB |
600 | #else |
601 | static inline void pwm_add_table(struct pwm_lookup *table, size_t num) | |
602 | { | |
603 | } | |
efb0de55 SK |
604 | |
605 | static inline void pwm_remove_table(struct pwm_lookup *table, size_t num) | |
606 | { | |
607 | } | |
0c2498f1 SH |
608 | #endif |
609 | ||
76abbdde HS |
610 | #ifdef CONFIG_PWM_SYSFS |
611 | void pwmchip_sysfs_export(struct pwm_chip *chip); | |
612 | void pwmchip_sysfs_unexport(struct pwm_chip *chip); | |
613 | #else | |
614 | static inline void pwmchip_sysfs_export(struct pwm_chip *chip) | |
615 | { | |
616 | } | |
617 | ||
618 | static inline void pwmchip_sysfs_unexport(struct pwm_chip *chip) | |
619 | { | |
620 | } | |
621 | #endif /* CONFIG_PWM_SYSFS */ | |
622 | ||
5243ef8b | 623 | #endif /* __LINUX_PWM_H */ |