1 | /* |
2 | * linux/include/linux/clk.h |
3 | * |
4 | * Copyright (C) 2004 ARM Limited. |
5 | * Written by Deep Blue Solutions Limited. |
6 | * Copyright (C) 2011-2012 Linaro Ltd <mturquette@linaro.org> |
7 | * |
8 | * This program is free software; you can redistribute it and/or modify |
9 | * it under the terms of the GNU General Public License version 2 as |
10 | * published by the Free Software Foundation. |
11 | */ |
12 | #ifndef __LINUX_CLK_H |
13 | #define __LINUX_CLK_H |
14 | |
15 | #include <linux/err.h> |
16 | #include <linux/kernel.h> |
17 | #include <linux/notifier.h> |
18 | |
19 | struct device; |
20 | struct clk; |
21 | struct device_node; |
22 | struct of_phandle_args; |
23 | |
24 | /** |
25 | * DOC: clk notifier callback types |
26 | * |
27 | * PRE_RATE_CHANGE - called immediately before the clk rate is changed, |
28 | * to indicate that the rate change will proceed. Drivers must |
29 | * immediately terminate any operations that will be affected by the |
30 | * rate change. Callbacks may either return NOTIFY_DONE, NOTIFY_OK, |
31 | * NOTIFY_STOP or NOTIFY_BAD. |
32 | * |
33 | * ABORT_RATE_CHANGE: called if the rate change failed for some reason |
34 | * after PRE_RATE_CHANGE. In this case, all registered notifiers on |
35 | * the clk will be called with ABORT_RATE_CHANGE. Callbacks must |
36 | * always return NOTIFY_DONE or NOTIFY_OK. |
37 | * |
38 | * POST_RATE_CHANGE - called after the clk rate change has successfully |
39 | * completed. Callbacks must always return NOTIFY_DONE or NOTIFY_OK. |
40 | * |
41 | */ |
42 | #define PRE_RATE_CHANGE BIT(0) |
43 | #define POST_RATE_CHANGE BIT(1) |
44 | #define ABORT_RATE_CHANGE BIT(2) |
45 | |
46 | /** |
47 | * struct clk_notifier - associate a clk with a notifier |
48 | * @clk: struct clk * to associate the notifier with |
49 | * @notifier_head: a blocking_notifier_head for this clk |
50 | * @node: linked list pointers |
51 | * |
52 | * A list of struct clk_notifier is maintained by the notifier code. |
53 | * An entry is created whenever code registers the first notifier on a |
54 | * particular @clk. Future notifiers on that @clk are added to the |
55 | * @notifier_head. |
56 | */ |
57 | struct clk_notifier { |
58 | struct clk *clk; |
59 | struct srcu_notifier_head notifier_head; |
60 | struct list_head node; |
61 | }; |
62 | |
63 | /** |
64 | * struct clk_notifier_data - rate data to pass to the notifier callback |
65 | * @clk: struct clk * being changed |
66 | * @old_rate: previous rate of this clk |
67 | * @new_rate: new rate of this clk |
68 | * |
69 | * For a pre-notifier, old_rate is the clk's rate before this rate |
70 | * change, and new_rate is what the rate will be in the future. For a |
71 | * post-notifier, old_rate and new_rate are both set to the clk's |
72 | * current rate (this was done to optimize the implementation). |
73 | */ |
74 | struct clk_notifier_data { |
75 | struct clk *clk; |
76 | unsigned long old_rate; |
77 | unsigned long new_rate; |
78 | }; |
79 | |
80 | /** |
81 | * struct clk_bulk_data - Data used for bulk clk operations. |
82 | * |
83 | * @id: clock consumer ID |
84 | * @clk: struct clk * to store the associated clock |
85 | * |
86 | * The CLK APIs provide a series of clk_bulk_() API calls as |
87 | * a convenience to consumers which require multiple clks. This |
88 | * structure is used to manage data for these calls. |
89 | */ |
90 | struct clk_bulk_data { |
91 | const char *id; |
92 | struct clk *clk; |
93 | }; |
94 | |
95 | #ifdef CONFIG_COMMON_CLK |
96 | |
97 | /** |
98 | * clk_notifier_register: register a clock rate-change notifier callback |
99 | * @clk: clock whose rate we are interested in |
100 | * @nb: notifier block with callback function pointer |
101 | * |
102 | * ProTip: debugging across notifier chains can be frustrating. Make sure that |
103 | * your notifier callback function prints a nice big warning in case of |
104 | * failure. |
105 | */ |
106 | int clk_notifier_register(struct clk *clk, struct notifier_block *nb); |
107 | |
108 | /** |
109 | * clk_notifier_unregister: unregister a clock rate-change notifier callback |
110 | * @clk: clock whose rate we are no longer interested in |
111 | * @nb: notifier block which will be unregistered |
112 | */ |
113 | int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb); |
114 | |
115 | /** |
116 | * clk_get_accuracy - obtain the clock accuracy in ppb (parts per billion) |
117 | * for a clock source. |
118 | * @clk: clock source |
119 | * |
120 | * This gets the clock source accuracy expressed in ppb. |
121 | * A perfect clock returns 0. |
122 | */ |
123 | long clk_get_accuracy(struct clk *clk); |
124 | |
125 | /** |
126 | * clk_set_phase - adjust the phase shift of a clock signal |
127 | * @clk: clock signal source |
128 | * @degrees: number of degrees the signal is shifted |
129 | * |
130 | * Shifts the phase of a clock signal by the specified degrees. Returns 0 on |
131 | * success, -EERROR otherwise. |
132 | */ |
133 | int clk_set_phase(struct clk *clk, int degrees); |
134 | |
135 | /** |
136 | * clk_get_phase - return the phase shift of a clock signal |
137 | * @clk: clock signal source |
138 | * |
139 | * Returns the phase shift of a clock node in degrees, otherwise returns |
140 | * -EERROR. |
141 | */ |
142 | int clk_get_phase(struct clk *clk); |
143 | |
144 | /** |
145 | * clk_set_duty_cycle - adjust the duty cycle ratio of a clock signal |
146 | * @clk: clock signal source |
147 | * @num: numerator of the duty cycle ratio to be applied |
148 | * @den: denominator of the duty cycle ratio to be applied |
149 | * |
150 | * Adjust the duty cycle of a clock signal by the specified ratio. Returns 0 on |
151 | * success, -EERROR otherwise. |
152 | */ |
153 | int clk_set_duty_cycle(struct clk *clk, unsigned int num, unsigned int den); |
154 | |
155 | /** |
156 | * clk_get_duty_cycle - return the duty cycle ratio of a clock signal |
157 | * @clk: clock signal source |
158 | * @scale: scaling factor to be applied to represent the ratio as an integer |
159 | * |
160 | * Returns the duty cycle ratio multiplied by the scale provided, otherwise |
161 | * returns -EERROR. |
162 | */ |
163 | int clk_get_scaled_duty_cycle(struct clk *clk, unsigned int scale); |
164 | |
165 | /** |
166 | * clk_is_match - check if two clk's point to the same hardware clock |
167 | * @p: clk compared against q |
168 | * @q: clk compared against p |
169 | * |
170 | * Returns true if the two struct clk pointers both point to the same hardware |
171 | * clock node. Put differently, returns true if @p and @q |
172 | * share the same &struct clk_core object. |
173 | * |
174 | * Returns false otherwise. Note that two NULL clks are treated as matching. |
175 | */ |
176 | bool clk_is_match(const struct clk *p, const struct clk *q); |
177 | |
178 | #else |
179 | |
180 | static inline int clk_notifier_register(struct clk *clk, |
181 | struct notifier_block *nb) |
182 | { |
183 | return -ENOTSUPP; |
184 | } |
185 | |
186 | static inline int clk_notifier_unregister(struct clk *clk, |
187 | struct notifier_block *nb) |
188 | { |
189 | return -ENOTSUPP; |
190 | } |
191 | |
192 | static inline long clk_get_accuracy(struct clk *clk) |
193 | { |
194 | return -ENOTSUPP; |
195 | } |
196 | |
197 | static inline long clk_set_phase(struct clk *clk, int phase) |
198 | { |
199 | return -ENOTSUPP; |
200 | } |
201 | |
202 | static inline long clk_get_phase(struct clk *clk) |
203 | { |
204 | return -ENOTSUPP; |
205 | } |
206 | |
207 | static inline int clk_set_duty_cycle(struct clk *clk, unsigned int num, |
208 | unsigned int den) |
209 | { |
210 | return -ENOTSUPP; |
211 | } |
212 | |
213 | static inline unsigned int clk_get_scaled_duty_cycle(struct clk *clk, |
214 | unsigned int scale) |
215 | { |
216 | return 0; |
217 | } |
218 | |
219 | static inline bool clk_is_match(const struct clk *p, const struct clk *q) |
220 | { |
221 | return p == q; |
222 | } |
223 | |
224 | #endif |
225 | |
226 | /** |
227 | * clk_prepare - prepare a clock source |
228 | * @clk: clock source |
229 | * |
230 | * This prepares the clock source for use. |
231 | * |
232 | * Must not be called from within atomic context. |
233 | */ |
234 | #ifdef CONFIG_HAVE_CLK_PREPARE |
235 | int clk_prepare(struct clk *clk); |
236 | int __must_check clk_bulk_prepare(int num_clks, |
237 | const struct clk_bulk_data *clks); |
238 | #else |
239 | static inline int clk_prepare(struct clk *clk) |
240 | { |
241 | might_sleep(); |
242 | return 0; |
243 | } |
244 | |
245 | static inline int __must_check clk_bulk_prepare(int num_clks, struct clk_bulk_data *clks) |
246 | { |
247 | might_sleep(); |
248 | return 0; |
249 | } |
250 | #endif |
251 | |
252 | /** |
253 | * clk_unprepare - undo preparation of a clock source |
254 | * @clk: clock source |
255 | * |
256 | * This undoes a previously prepared clock. The caller must balance |
257 | * the number of prepare and unprepare calls. |
258 | * |
259 | * Must not be called from within atomic context. |
260 | */ |
261 | #ifdef CONFIG_HAVE_CLK_PREPARE |
262 | void clk_unprepare(struct clk *clk); |
263 | void clk_bulk_unprepare(int num_clks, const struct clk_bulk_data *clks); |
264 | #else |
265 | static inline void clk_unprepare(struct clk *clk) |
266 | { |
267 | might_sleep(); |
268 | } |
269 | static inline void clk_bulk_unprepare(int num_clks, struct clk_bulk_data *clks) |
270 | { |
271 | might_sleep(); |
272 | } |
273 | #endif |
274 | |
275 | #ifdef CONFIG_HAVE_CLK |
276 | /** |
277 | * clk_get - lookup and obtain a reference to a clock producer. |
278 | * @dev: device for clock "consumer" |
279 | * @id: clock consumer ID |
280 | * |
281 | * Returns a struct clk corresponding to the clock producer, or |
282 | * valid IS_ERR() condition containing errno. The implementation |
283 | * uses @dev and @id to determine the clock consumer, and thereby |
284 | * the clock producer. (IOW, @id may be identical strings, but |
285 | * clk_get may return different clock producers depending on @dev.) |
286 | * |
287 | * Drivers must assume that the clock source is not enabled. |
288 | * |
289 | * clk_get should not be called from within interrupt context. |
290 | */ |
291 | struct clk *clk_get(struct device *dev, const char *id); |
292 | |
293 | /** |
294 | * clk_bulk_get - lookup and obtain a number of references to clock producer. |
295 | * @dev: device for clock "consumer" |
296 | * @num_clks: the number of clk_bulk_data |
297 | * @clks: the clk_bulk_data table of consumer |
298 | * |
299 | * This helper function allows drivers to get several clk consumers in one |
300 | * operation. If any of the clk cannot be acquired then any clks |
301 | * that were obtained will be freed before returning to the caller. |
302 | * |
303 | * Returns 0 if all clocks specified in clk_bulk_data table are obtained |
304 | * successfully, or valid IS_ERR() condition containing errno. |
305 | * The implementation uses @dev and @clk_bulk_data.id to determine the |
306 | * clock consumer, and thereby the clock producer. |
307 | * The clock returned is stored in each @clk_bulk_data.clk field. |
308 | * |
309 | * Drivers must assume that the clock source is not enabled. |
310 | * |
311 | * clk_bulk_get should not be called from within interrupt context. |
312 | */ |
313 | int __must_check clk_bulk_get(struct device *dev, int num_clks, |
314 | struct clk_bulk_data *clks); |
315 | /** |
316 | * clk_bulk_get_all - lookup and obtain all available references to clock |
317 | * producer. |
318 | * @dev: device for clock "consumer" |
319 | * @clks: pointer to the clk_bulk_data table of consumer |
320 | * |
321 | * This helper function allows drivers to get all clk consumers in one |
322 | * operation. If any of the clk cannot be acquired then any clks |
323 | * that were obtained will be freed before returning to the caller. |
324 | * |
325 | * Returns a positive value for the number of clocks obtained while the |
326 | * clock references are stored in the clk_bulk_data table in @clks field. |
327 | * Returns 0 if there're none and a negative value if something failed. |
328 | * |
329 | * Drivers must assume that the clock source is not enabled. |
330 | * |
331 | * clk_bulk_get should not be called from within interrupt context. |
332 | */ |
333 | int __must_check clk_bulk_get_all(struct device *dev, |
334 | struct clk_bulk_data **clks); |
335 | /** |
336 | * devm_clk_bulk_get - managed get multiple clk consumers |
337 | * @dev: device for clock "consumer" |
338 | * @num_clks: the number of clk_bulk_data |
339 | * @clks: the clk_bulk_data table of consumer |
340 | * |
341 | * Return 0 on success, an errno on failure. |
342 | * |
343 | * This helper function allows drivers to get several clk |
344 | * consumers in one operation with management, the clks will |
345 | * automatically be freed when the device is unbound. |
346 | */ |
347 | int __must_check devm_clk_bulk_get(struct device *dev, int num_clks, |
348 | struct clk_bulk_data *clks); |
349 | /** |
350 | * devm_clk_bulk_get_all - managed get multiple clk consumers |
351 | * @dev: device for clock "consumer" |
352 | * @clks: pointer to the clk_bulk_data table of consumer |
353 | * |
354 | * Returns a positive value for the number of clocks obtained while the |
355 | * clock references are stored in the clk_bulk_data table in @clks field. |
356 | * Returns 0 if there're none and a negative value if something failed. |
357 | * |
358 | * This helper function allows drivers to get several clk |
359 | * consumers in one operation with management, the clks will |
360 | * automatically be freed when the device is unbound. |
361 | */ |
362 | |
363 | int __must_check devm_clk_bulk_get_all(struct device *dev, |
364 | struct clk_bulk_data **clks); |
365 | |
366 | /** |
367 | * devm_clk_get - lookup and obtain a managed reference to a clock producer. |
368 | * @dev: device for clock "consumer" |
369 | * @id: clock consumer ID |
370 | * |
371 | * Returns a struct clk corresponding to the clock producer, or |
372 | * valid IS_ERR() condition containing errno. The implementation |
373 | * uses @dev and @id to determine the clock consumer, and thereby |
374 | * the clock producer. (IOW, @id may be identical strings, but |
375 | * clk_get may return different clock producers depending on @dev.) |
376 | * |
377 | * Drivers must assume that the clock source is not enabled. |
378 | * |
379 | * devm_clk_get should not be called from within interrupt context. |
380 | * |
381 | * The clock will automatically be freed when the device is unbound |
382 | * from the bus. |
383 | */ |
384 | struct clk *devm_clk_get(struct device *dev, const char *id); |
385 | |
386 | /** |
387 | * devm_clk_get_optional - lookup and obtain a managed reference to an optional |
388 | * clock producer. |
389 | * @dev: device for clock "consumer" |
390 | * @id: clock consumer ID |
391 | * |
392 | * Behaves the same as devm_clk_get() except where there is no clock producer. |
393 | * In this case, instead of returning -ENOENT, the function returns NULL. |
394 | */ |
395 | struct clk *devm_clk_get_optional(struct device *dev, const char *id); |
396 | |
397 | /** |
398 | * devm_get_clk_from_child - lookup and obtain a managed reference to a |
399 | * clock producer from child node. |
400 | * @dev: device for clock "consumer" |
401 | * @np: pointer to clock consumer node |
402 | * @con_id: clock consumer ID |
403 | * |
404 | * This function parses the clocks, and uses them to look up the |
405 | * struct clk from the registered list of clock providers by using |
406 | * @np and @con_id |
407 | * |
408 | * The clock will automatically be freed when the device is unbound |
409 | * from the bus. |
410 | */ |
411 | struct clk *devm_get_clk_from_child(struct device *dev, |
412 | struct device_node *np, const char *con_id); |
413 | /** |
414 | * clk_rate_exclusive_get - get exclusivity over the rate control of a |
415 | * producer |
416 | * @clk: clock source |
417 | * |
418 | * This function allows drivers to get exclusive control over the rate of a |
419 | * provider. It prevents any other consumer to execute, even indirectly, |
420 | * opereation which could alter the rate of the provider or cause glitches |
421 | * |
422 | * If exlusivity is claimed more than once on clock, even by the same driver, |
423 | * the rate effectively gets locked as exclusivity can't be preempted. |
424 | * |
425 | * Must not be called from within atomic context. |
426 | * |
427 | * Returns success (0) or negative errno. |
428 | */ |
429 | int clk_rate_exclusive_get(struct clk *clk); |
430 | |
431 | /** |
432 | * clk_rate_exclusive_put - release exclusivity over the rate control of a |
433 | * producer |
434 | * @clk: clock source |
435 | * |
436 | * This function allows drivers to release the exclusivity it previously got |
437 | * from clk_rate_exclusive_get() |
438 | * |
439 | * The caller must balance the number of clk_rate_exclusive_get() and |
440 | * clk_rate_exclusive_put() calls. |
441 | * |
442 | * Must not be called from within atomic context. |
443 | */ |
444 | void clk_rate_exclusive_put(struct clk *clk); |
445 | |
446 | /** |
447 | * clk_enable - inform the system when the clock source should be running. |
448 | * @clk: clock source |
449 | * |
450 | * If the clock can not be enabled/disabled, this should return success. |
451 | * |
452 | * May be called from atomic contexts. |
453 | * |
454 | * Returns success (0) or negative errno. |
455 | */ |
456 | int clk_enable(struct clk *clk); |
457 | |
458 | /** |
459 | * clk_bulk_enable - inform the system when the set of clks should be running. |
460 | * @num_clks: the number of clk_bulk_data |
461 | * @clks: the clk_bulk_data table of consumer |
462 | * |
463 | * May be called from atomic contexts. |
464 | * |
465 | * Returns success (0) or negative errno. |
466 | */ |
467 | int __must_check clk_bulk_enable(int num_clks, |
468 | const struct clk_bulk_data *clks); |
469 | |
470 | /** |
471 | * clk_disable - inform the system when the clock source is no longer required. |
472 | * @clk: clock source |
473 | * |
474 | * Inform the system that a clock source is no longer required by |
475 | * a driver and may be shut down. |
476 | * |
477 | * May be called from atomic contexts. |
478 | * |
479 | * Implementation detail: if the clock source is shared between |
480 | * multiple drivers, clk_enable() calls must be balanced by the |
481 | * same number of clk_disable() calls for the clock source to be |
482 | * disabled. |
483 | */ |
484 | void clk_disable(struct clk *clk); |
485 | |
486 | /** |
487 | * clk_bulk_disable - inform the system when the set of clks is no |
488 | * longer required. |
489 | * @num_clks: the number of clk_bulk_data |
490 | * @clks: the clk_bulk_data table of consumer |
491 | * |
492 | * Inform the system that a set of clks is no longer required by |
493 | * a driver and may be shut down. |
494 | * |
495 | * May be called from atomic contexts. |
496 | * |
497 | * Implementation detail: if the set of clks is shared between |
498 | * multiple drivers, clk_bulk_enable() calls must be balanced by the |
499 | * same number of clk_bulk_disable() calls for the clock source to be |
500 | * disabled. |
501 | */ |
502 | void clk_bulk_disable(int num_clks, const struct clk_bulk_data *clks); |
503 | |
504 | /** |
505 | * clk_get_rate - obtain the current clock rate (in Hz) for a clock source. |
506 | * This is only valid once the clock source has been enabled. |
507 | * @clk: clock source |
508 | */ |
509 | unsigned long clk_get_rate(struct clk *clk); |
510 | |
511 | /** |
512 | * clk_put - "free" the clock source |
513 | * @clk: clock source |
514 | * |
515 | * Note: drivers must ensure that all clk_enable calls made on this |
516 | * clock source are balanced by clk_disable calls prior to calling |
517 | * this function. |
518 | * |
519 | * clk_put should not be called from within interrupt context. |
520 | */ |
521 | void clk_put(struct clk *clk); |
522 | |
523 | /** |
524 | * clk_bulk_put - "free" the clock source |
525 | * @num_clks: the number of clk_bulk_data |
526 | * @clks: the clk_bulk_data table of consumer |
527 | * |
528 | * Note: drivers must ensure that all clk_bulk_enable calls made on this |
529 | * clock source are balanced by clk_bulk_disable calls prior to calling |
530 | * this function. |
531 | * |
532 | * clk_bulk_put should not be called from within interrupt context. |
533 | */ |
534 | void clk_bulk_put(int num_clks, struct clk_bulk_data *clks); |
535 | |
536 | /** |
537 | * clk_bulk_put_all - "free" all the clock source |
538 | * @num_clks: the number of clk_bulk_data |
539 | * @clks: the clk_bulk_data table of consumer |
540 | * |
541 | * Note: drivers must ensure that all clk_bulk_enable calls made on this |
542 | * clock source are balanced by clk_bulk_disable calls prior to calling |
543 | * this function. |
544 | * |
545 | * clk_bulk_put_all should not be called from within interrupt context. |
546 | */ |
547 | void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks); |
548 | |
549 | /** |
550 | * devm_clk_put - "free" a managed clock source |
551 | * @dev: device used to acquire the clock |
552 | * @clk: clock source acquired with devm_clk_get() |
553 | * |
554 | * Note: drivers must ensure that all clk_enable calls made on this |
555 | * clock source are balanced by clk_disable calls prior to calling |
556 | * this function. |
557 | * |
558 | * clk_put should not be called from within interrupt context. |
559 | */ |
560 | void devm_clk_put(struct device *dev, struct clk *clk); |
561 | |
562 | /* |
563 | * The remaining APIs are optional for machine class support. |
564 | */ |
565 | |
566 | |
567 | /** |
568 | * clk_round_rate - adjust a rate to the exact rate a clock can provide |
569 | * @clk: clock source |
570 | * @rate: desired clock rate in Hz |
571 | * |
572 | * This answers the question "if I were to pass @rate to clk_set_rate(), |
573 | * what clock rate would I end up with?" without changing the hardware |
574 | * in any way. In other words: |
575 | * |
576 | * rate = clk_round_rate(clk, r); |
577 | * |
578 | * and: |
579 | * |
580 | * clk_set_rate(clk, r); |
581 | * rate = clk_get_rate(clk); |
582 | * |
583 | * are equivalent except the former does not modify the clock hardware |
584 | * in any way. |
585 | * |
586 | * Returns rounded clock rate in Hz, or negative errno. |
587 | */ |
588 | long clk_round_rate(struct clk *clk, unsigned long rate); |
589 | |
590 | /** |
591 | * clk_set_rate - set the clock rate for a clock source |
592 | * @clk: clock source |
593 | * @rate: desired clock rate in Hz |
594 | * |
595 | * Returns success (0) or negative errno. |
596 | */ |
597 | int clk_set_rate(struct clk *clk, unsigned long rate); |
598 | |
599 | /** |
600 | * clk_set_rate_exclusive- set the clock rate and claim exclusivity over |
601 | * clock source |
602 | * @clk: clock source |
603 | * @rate: desired clock rate in Hz |
604 | * |
605 | * This helper function allows drivers to atomically set the rate of a producer |
606 | * and claim exclusivity over the rate control of the producer. |
607 | * |
608 | * It is essentially a combination of clk_set_rate() and |
609 | * clk_rate_exclusite_get(). Caller must balance this call with a call to |
610 | * clk_rate_exclusive_put() |
611 | * |
612 | * Returns success (0) or negative errno. |
613 | */ |
614 | int clk_set_rate_exclusive(struct clk *clk, unsigned long rate); |
615 | |
616 | /** |
617 | * clk_has_parent - check if a clock is a possible parent for another |
618 | * @clk: clock source |
619 | * @parent: parent clock source |
620 | * |
621 | * This function can be used in drivers that need to check that a clock can be |
622 | * the parent of another without actually changing the parent. |
623 | * |
624 | * Returns true if @parent is a possible parent for @clk, false otherwise. |
625 | */ |
626 | bool clk_has_parent(struct clk *clk, struct clk *parent); |
627 | |
628 | /** |
629 | * clk_set_rate_range - set a rate range for a clock source |
630 | * @clk: clock source |
631 | * @min: desired minimum clock rate in Hz, inclusive |
632 | * @max: desired maximum clock rate in Hz, inclusive |
633 | * |
634 | * Returns success (0) or negative errno. |
635 | */ |
636 | int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max); |
637 | |
638 | /** |
639 | * clk_set_min_rate - set a minimum clock rate for a clock source |
640 | * @clk: clock source |
641 | * @rate: desired minimum clock rate in Hz, inclusive |
642 | * |
643 | * Returns success (0) or negative errno. |
644 | */ |
645 | int clk_set_min_rate(struct clk *clk, unsigned long rate); |
646 | |
647 | /** |
648 | * clk_set_max_rate - set a maximum clock rate for a clock source |
649 | * @clk: clock source |
650 | * @rate: desired maximum clock rate in Hz, inclusive |
651 | * |
652 | * Returns success (0) or negative errno. |
653 | */ |
654 | int clk_set_max_rate(struct clk *clk, unsigned long rate); |
655 | |
656 | /** |
657 | * clk_set_parent - set the parent clock source for this clock |
658 | * @clk: clock source |
659 | * @parent: parent clock source |
660 | * |
661 | * Returns success (0) or negative errno. |
662 | */ |
663 | int clk_set_parent(struct clk *clk, struct clk *parent); |
664 | |
665 | /** |
666 | * clk_get_parent - get the parent clock source for this clock |
667 | * @clk: clock source |
668 | * |
669 | * Returns struct clk corresponding to parent clock source, or |
670 | * valid IS_ERR() condition containing errno. |
671 | */ |
672 | struct clk *clk_get_parent(struct clk *clk); |
673 | |
674 | /** |
675 | * clk_get_sys - get a clock based upon the device name |
676 | * @dev_id: device name |
677 | * @con_id: connection ID |
678 | * |
679 | * Returns a struct clk corresponding to the clock producer, or |
680 | * valid IS_ERR() condition containing errno. The implementation |
681 | * uses @dev_id and @con_id to determine the clock consumer, and |
682 | * thereby the clock producer. In contrast to clk_get() this function |
683 | * takes the device name instead of the device itself for identification. |
684 | * |
685 | * Drivers must assume that the clock source is not enabled. |
686 | * |
687 | * clk_get_sys should not be called from within interrupt context. |
688 | */ |
689 | struct clk *clk_get_sys(const char *dev_id, const char *con_id); |
690 | |
691 | /** |
692 | * clk_save_context - save clock context for poweroff |
693 | * |
694 | * Saves the context of the clock register for powerstates in which the |
695 | * contents of the registers will be lost. Occurs deep within the suspend |
696 | * code so locking is not necessary. |
697 | */ |
698 | int clk_save_context(void); |
699 | |
700 | /** |
701 | * clk_restore_context - restore clock context after poweroff |
702 | * |
703 | * This occurs with all clocks enabled. Occurs deep within the resume code |
704 | * so locking is not necessary. |
705 | */ |
706 | void clk_restore_context(void); |
707 | |
708 | #else /* !CONFIG_HAVE_CLK */ |
709 | |
710 | static inline struct clk *clk_get(struct device *dev, const char *id) |
711 | { |
712 | return NULL; |
713 | } |
714 | |
715 | static inline int __must_check clk_bulk_get(struct device *dev, int num_clks, |
716 | struct clk_bulk_data *clks) |
717 | { |
718 | return 0; |
719 | } |
720 | |
721 | static inline int __must_check clk_bulk_get_all(struct device *dev, |
722 | struct clk_bulk_data **clks) |
723 | { |
724 | return 0; |
725 | } |
726 | |
727 | static inline struct clk *devm_clk_get(struct device *dev, const char *id) |
728 | { |
729 | return NULL; |
730 | } |
731 | |
732 | static inline struct clk *devm_clk_get_optional(struct device *dev, |
733 | const char *id) |
734 | { |
735 | return NULL; |
736 | } |
737 | |
738 | static inline int __must_check devm_clk_bulk_get(struct device *dev, int num_clks, |
739 | struct clk_bulk_data *clks) |
740 | { |
741 | return 0; |
742 | } |
743 | |
744 | static inline int __must_check devm_clk_bulk_get_all(struct device *dev, |
745 | struct clk_bulk_data **clks) |
746 | { |
747 | |
748 | return 0; |
749 | } |
750 | |
751 | static inline struct clk *devm_get_clk_from_child(struct device *dev, |
752 | struct device_node *np, const char *con_id) |
753 | { |
754 | return NULL; |
755 | } |
756 | |
757 | static inline void clk_put(struct clk *clk) {} |
758 | |
759 | static inline void clk_bulk_put(int num_clks, struct clk_bulk_data *clks) {} |
760 | |
761 | static inline void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks) {} |
762 | |
763 | static inline void devm_clk_put(struct device *dev, struct clk *clk) {} |
764 | |
765 | |
766 | static inline int clk_rate_exclusive_get(struct clk *clk) |
767 | { |
768 | return 0; |
769 | } |
770 | |
771 | static inline void clk_rate_exclusive_put(struct clk *clk) {} |
772 | |
773 | static inline int clk_enable(struct clk *clk) |
774 | { |
775 | return 0; |
776 | } |
777 | |
778 | static inline int __must_check clk_bulk_enable(int num_clks, struct clk_bulk_data *clks) |
779 | { |
780 | return 0; |
781 | } |
782 | |
783 | static inline void clk_disable(struct clk *clk) {} |
784 | |
785 | |
786 | static inline void clk_bulk_disable(int num_clks, |
787 | struct clk_bulk_data *clks) {} |
788 | |
789 | static inline unsigned long clk_get_rate(struct clk *clk) |
790 | { |
791 | return 0; |
792 | } |
793 | |
794 | static inline int clk_set_rate(struct clk *clk, unsigned long rate) |
795 | { |
796 | return 0; |
797 | } |
798 | |
799 | static inline int clk_set_rate_exclusive(struct clk *clk, unsigned long rate) |
800 | { |
801 | return 0; |
802 | } |
803 | |
804 | static inline long clk_round_rate(struct clk *clk, unsigned long rate) |
805 | { |
806 | return 0; |
807 | } |
808 | |
809 | static inline bool clk_has_parent(struct clk *clk, struct clk *parent) |
810 | { |
811 | return true; |
812 | } |
813 | |
814 | static inline int clk_set_parent(struct clk *clk, struct clk *parent) |
815 | { |
816 | return 0; |
817 | } |
818 | |
819 | static inline struct clk *clk_get_parent(struct clk *clk) |
820 | { |
821 | return NULL; |
822 | } |
823 | |
824 | static inline struct clk *clk_get_sys(const char *dev_id, const char *con_id) |
825 | { |
826 | return NULL; |
827 | } |
828 | |
829 | static inline int clk_save_context(void) |
830 | { |
831 | return 0; |
832 | } |
833 | |
834 | static inline void clk_restore_context(void) {} |
835 | |
836 | #endif |
837 | |
838 | /* clk_prepare_enable helps cases using clk_enable in non-atomic context. */ |
839 | static inline int clk_prepare_enable(struct clk *clk) |
840 | { |
841 | int ret; |
842 | |
843 | ret = clk_prepare(clk); |
844 | if (ret) |
845 | return ret; |
846 | ret = clk_enable(clk); |
847 | if (ret) |
848 | clk_unprepare(clk); |
849 | |
850 | return ret; |
851 | } |
852 | |
853 | /* clk_disable_unprepare helps cases using clk_disable in non-atomic context. */ |
854 | static inline void clk_disable_unprepare(struct clk *clk) |
855 | { |
856 | clk_disable(clk); |
857 | clk_unprepare(clk); |
858 | } |
859 | |
860 | static inline int __must_check clk_bulk_prepare_enable(int num_clks, |
861 | struct clk_bulk_data *clks) |
862 | { |
863 | int ret; |
864 | |
865 | ret = clk_bulk_prepare(num_clks, clks); |
866 | if (ret) |
867 | return ret; |
868 | ret = clk_bulk_enable(num_clks, clks); |
869 | if (ret) |
870 | clk_bulk_unprepare(num_clks, clks); |
871 | |
872 | return ret; |
873 | } |
874 | |
875 | static inline void clk_bulk_disable_unprepare(int num_clks, |
876 | struct clk_bulk_data *clks) |
877 | { |
878 | clk_bulk_disable(num_clks, clks); |
879 | clk_bulk_unprepare(num_clks, clks); |
880 | } |
881 | |
882 | /** |
883 | * clk_get_optional - lookup and obtain a reference to an optional clock |
884 | * producer. |
885 | * @dev: device for clock "consumer" |
886 | * @id: clock consumer ID |
887 | * |
888 | * Behaves the same as clk_get() except where there is no clock producer. In |
889 | * this case, instead of returning -ENOENT, the function returns NULL. |
890 | */ |
891 | static inline struct clk *clk_get_optional(struct device *dev, const char *id) |
892 | { |
893 | struct clk *clk = clk_get(dev, id); |
894 | |
895 | if (clk == ERR_PTR(-ENOENT)) |
896 | return NULL; |
897 | |
898 | return clk; |
899 | } |
900 | |
901 | #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) |
902 | struct clk *of_clk_get(struct device_node *np, int index); |
903 | struct clk *of_clk_get_by_name(struct device_node *np, const char *name); |
904 | struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec); |
905 | #else |
906 | static inline struct clk *of_clk_get(struct device_node *np, int index) |
907 | { |
908 | return ERR_PTR(-ENOENT); |
909 | } |
910 | static inline struct clk *of_clk_get_by_name(struct device_node *np, |
911 | const char *name) |
912 | { |
913 | return ERR_PTR(-ENOENT); |
914 | } |
915 | static inline struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec) |
916 | { |
917 | return ERR_PTR(-ENOENT); |
918 | } |
919 | #endif |
920 | |
921 | #endif |
922 | |