1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * linux/include/linux/clk.h
5 * Copyright (C) 2004 ARM Limited.
6 * Written by Deep Blue Solutions Limited.
7 * Copyright (C) 2011-2012 Linaro Ltd <mturquette@linaro.org>
12 #include <linux/err.h>
13 #include <linux/kernel.h>
14 #include <linux/notifier.h>
19 struct of_phandle_args;
22 * DOC: clk notifier callback types
24 * PRE_RATE_CHANGE - called immediately before the clk rate is changed,
25 * to indicate that the rate change will proceed. Drivers must
26 * immediately terminate any operations that will be affected by the
27 * rate change. Callbacks may either return NOTIFY_DONE, NOTIFY_OK,
28 * NOTIFY_STOP or NOTIFY_BAD.
30 * ABORT_RATE_CHANGE: called if the rate change failed for some reason
31 * after PRE_RATE_CHANGE. In this case, all registered notifiers on
32 * the clk will be called with ABORT_RATE_CHANGE. Callbacks must
33 * always return NOTIFY_DONE or NOTIFY_OK.
35 * POST_RATE_CHANGE - called after the clk rate change has successfully
36 * completed. Callbacks must always return NOTIFY_DONE or NOTIFY_OK.
39 #define PRE_RATE_CHANGE BIT(0)
40 #define POST_RATE_CHANGE BIT(1)
41 #define ABORT_RATE_CHANGE BIT(2)
44 * struct clk_notifier - associate a clk with a notifier
45 * @clk: struct clk * to associate the notifier with
46 * @notifier_head: a blocking_notifier_head for this clk
47 * @node: linked list pointers
49 * A list of struct clk_notifier is maintained by the notifier code.
50 * An entry is created whenever code registers the first notifier on a
51 * particular @clk. Future notifiers on that @clk are added to the
56 struct srcu_notifier_head notifier_head;
57 struct list_head node;
61 * struct clk_notifier_data - rate data to pass to the notifier callback
62 * @clk: struct clk * being changed
63 * @old_rate: previous rate of this clk
64 * @new_rate: new rate of this clk
66 * For a pre-notifier, old_rate is the clk's rate before this rate
67 * change, and new_rate is what the rate will be in the future. For a
68 * post-notifier, old_rate and new_rate are both set to the clk's
69 * current rate (this was done to optimize the implementation).
71 struct clk_notifier_data {
73 unsigned long old_rate;
74 unsigned long new_rate;
78 * struct clk_bulk_data - Data used for bulk clk operations.
80 * @id: clock consumer ID
81 * @clk: struct clk * to store the associated clock
83 * The CLK APIs provide a series of clk_bulk_() API calls as
84 * a convenience to consumers which require multiple clks. This
85 * structure is used to manage data for these calls.
87 struct clk_bulk_data {
92 #ifdef CONFIG_COMMON_CLK
95 * clk_notifier_register - register a clock rate-change notifier callback
96 * @clk: clock whose rate we are interested in
97 * @nb: notifier block with callback function pointer
99 * ProTip: debugging across notifier chains can be frustrating. Make sure that
100 * your notifier callback function prints a nice big warning in case of
103 int clk_notifier_register(struct clk *clk, struct notifier_block *nb);
106 * clk_notifier_unregister - unregister a clock rate-change notifier callback
107 * @clk: clock whose rate we are no longer interested in
108 * @nb: notifier block which will be unregistered
110 int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb);
113 * devm_clk_notifier_register - register a managed rate-change notifier callback
114 * @dev: device for clock "consumer"
115 * @clk: clock whose rate we are interested in
116 * @nb: notifier block with callback function pointer
118 * Returns 0 on success, -EERROR otherwise
120 int devm_clk_notifier_register(struct device *dev, struct clk *clk,
121 struct notifier_block *nb);
124 * clk_get_accuracy - obtain the clock accuracy in ppb (parts per billion)
125 * for a clock source.
128 * This gets the clock source accuracy expressed in ppb.
129 * A perfect clock returns 0.
131 long clk_get_accuracy(struct clk *clk);
134 * clk_set_phase - adjust the phase shift of a clock signal
135 * @clk: clock signal source
136 * @degrees: number of degrees the signal is shifted
138 * Shifts the phase of a clock signal by the specified degrees. Returns 0 on
139 * success, -EERROR otherwise.
141 int clk_set_phase(struct clk *clk, int degrees);
144 * clk_get_phase - return the phase shift of a clock signal
145 * @clk: clock signal source
147 * Returns the phase shift of a clock node in degrees, otherwise returns
150 int clk_get_phase(struct clk *clk);
153 * clk_set_duty_cycle - adjust the duty cycle ratio of a clock signal
154 * @clk: clock signal source
155 * @num: numerator of the duty cycle ratio to be applied
156 * @den: denominator of the duty cycle ratio to be applied
158 * Adjust the duty cycle of a clock signal by the specified ratio. Returns 0 on
159 * success, -EERROR otherwise.
161 int clk_set_duty_cycle(struct clk *clk, unsigned int num, unsigned int den);
164 * clk_get_scaled_duty_cycle - return the duty cycle ratio of a clock signal
165 * @clk: clock signal source
166 * @scale: scaling factor to be applied to represent the ratio as an integer
168 * Returns the duty cycle ratio multiplied by the scale provided, otherwise
171 int clk_get_scaled_duty_cycle(struct clk *clk, unsigned int scale);
174 * clk_is_match - check if two clk's point to the same hardware clock
175 * @p: clk compared against q
176 * @q: clk compared against p
178 * Returns true if the two struct clk pointers both point to the same hardware
179 * clock node. Put differently, returns true if @p and @q
180 * share the same &struct clk_core object.
182 * Returns false otherwise. Note that two NULL clks are treated as matching.
184 bool clk_is_match(const struct clk *p, const struct clk *q);
187 * clk_rate_exclusive_get - get exclusivity over the rate control of a
191 * This function allows drivers to get exclusive control over the rate of a
192 * provider. It prevents any other consumer to execute, even indirectly,
193 * opereation which could alter the rate of the provider or cause glitches
195 * If exlusivity is claimed more than once on clock, even by the same driver,
196 * the rate effectively gets locked as exclusivity can't be preempted.
198 * Must not be called from within atomic context.
200 * Returns success (0) or negative errno.
202 int clk_rate_exclusive_get(struct clk *clk);
205 * clk_rate_exclusive_put - release exclusivity over the rate control of a
209 * This function allows drivers to release the exclusivity it previously got
210 * from clk_rate_exclusive_get()
212 * The caller must balance the number of clk_rate_exclusive_get() and
213 * clk_rate_exclusive_put() calls.
215 * Must not be called from within atomic context.
217 void clk_rate_exclusive_put(struct clk *clk);
221 static inline int clk_notifier_register(struct clk *clk,
222 struct notifier_block *nb)
227 static inline int clk_notifier_unregister(struct clk *clk,
228 struct notifier_block *nb)
233 static inline int devm_clk_notifier_register(struct device *dev,
235 struct notifier_block *nb)
240 static inline long clk_get_accuracy(struct clk *clk)
245 static inline long clk_set_phase(struct clk *clk, int phase)
250 static inline long clk_get_phase(struct clk *clk)
255 static inline int clk_set_duty_cycle(struct clk *clk, unsigned int num,
261 static inline unsigned int clk_get_scaled_duty_cycle(struct clk *clk,
267 static inline bool clk_is_match(const struct clk *p, const struct clk *q)
272 static inline int clk_rate_exclusive_get(struct clk *clk)
277 static inline void clk_rate_exclusive_put(struct clk *clk) {}
281 #ifdef CONFIG_HAVE_CLK_PREPARE
283 * clk_prepare - prepare a clock source
286 * This prepares the clock source for use.
288 * Must not be called from within atomic context.
290 int clk_prepare(struct clk *clk);
291 int __must_check clk_bulk_prepare(int num_clks,
292 const struct clk_bulk_data *clks);
295 * clk_is_enabled_when_prepared - indicate if preparing a clock also enables it.
298 * Returns true if clk_prepare() implicitly enables the clock, effectively
299 * making clk_enable()/clk_disable() no-ops, false otherwise.
301 * This is of interest mainly to the power management code where actually
302 * disabling the clock also requires unpreparing it to have any material
305 * Regardless of the value returned here, the caller must always invoke
306 * clk_enable() or clk_prepare_enable() and counterparts for usage counts
309 bool clk_is_enabled_when_prepared(struct clk *clk);
311 static inline int clk_prepare(struct clk *clk)
317 static inline int __must_check
318 clk_bulk_prepare(int num_clks, const struct clk_bulk_data *clks)
324 static inline bool clk_is_enabled_when_prepared(struct clk *clk)
331 * clk_unprepare - undo preparation of a clock source
334 * This undoes a previously prepared clock. The caller must balance
335 * the number of prepare and unprepare calls.
337 * Must not be called from within atomic context.
339 #ifdef CONFIG_HAVE_CLK_PREPARE
340 void clk_unprepare(struct clk *clk);
341 void clk_bulk_unprepare(int num_clks, const struct clk_bulk_data *clks);
343 static inline void clk_unprepare(struct clk *clk)
347 static inline void clk_bulk_unprepare(int num_clks,
348 const struct clk_bulk_data *clks)
354 #ifdef CONFIG_HAVE_CLK
356 * clk_get - lookup and obtain a reference to a clock producer.
357 * @dev: device for clock "consumer"
358 * @id: clock consumer ID
360 * Returns a struct clk corresponding to the clock producer, or
361 * valid IS_ERR() condition containing errno. The implementation
362 * uses @dev and @id to determine the clock consumer, and thereby
363 * the clock producer. (IOW, @id may be identical strings, but
364 * clk_get may return different clock producers depending on @dev.)
366 * Drivers must assume that the clock source is not enabled.
368 * clk_get should not be called from within interrupt context.
370 struct clk *clk_get(struct device *dev, const char *id);
373 * clk_bulk_get - lookup and obtain a number of references to clock producer.
374 * @dev: device for clock "consumer"
375 * @num_clks: the number of clk_bulk_data
376 * @clks: the clk_bulk_data table of consumer
378 * This helper function allows drivers to get several clk consumers in one
379 * operation. If any of the clk cannot be acquired then any clks
380 * that were obtained will be freed before returning to the caller.
382 * Returns 0 if all clocks specified in clk_bulk_data table are obtained
383 * successfully, or valid IS_ERR() condition containing errno.
384 * The implementation uses @dev and @clk_bulk_data.id to determine the
385 * clock consumer, and thereby the clock producer.
386 * The clock returned is stored in each @clk_bulk_data.clk field.
388 * Drivers must assume that the clock source is not enabled.
390 * clk_bulk_get should not be called from within interrupt context.
392 int __must_check clk_bulk_get(struct device *dev, int num_clks,
393 struct clk_bulk_data *clks);
395 * clk_bulk_get_all - lookup and obtain all available references to clock
397 * @dev: device for clock "consumer"
398 * @clks: pointer to the clk_bulk_data table of consumer
400 * This helper function allows drivers to get all clk consumers in one
401 * operation. If any of the clk cannot be acquired then any clks
402 * that were obtained will be freed before returning to the caller.
404 * Returns a positive value for the number of clocks obtained while the
405 * clock references are stored in the clk_bulk_data table in @clks field.
406 * Returns 0 if there're none and a negative value if something failed.
408 * Drivers must assume that the clock source is not enabled.
410 * clk_bulk_get should not be called from within interrupt context.
412 int __must_check clk_bulk_get_all(struct device *dev,
413 struct clk_bulk_data **clks);
416 * clk_bulk_get_optional - lookup and obtain a number of references to clock producer
417 * @dev: device for clock "consumer"
418 * @num_clks: the number of clk_bulk_data
419 * @clks: the clk_bulk_data table of consumer
421 * Behaves the same as clk_bulk_get() except where there is no clock producer.
422 * In this case, instead of returning -ENOENT, the function returns 0 and
423 * NULL for a clk for which a clock producer could not be determined.
425 int __must_check clk_bulk_get_optional(struct device *dev, int num_clks,
426 struct clk_bulk_data *clks);
428 * devm_clk_bulk_get - managed get multiple clk consumers
429 * @dev: device for clock "consumer"
430 * @num_clks: the number of clk_bulk_data
431 * @clks: the clk_bulk_data table of consumer
433 * Return 0 on success, an errno on failure.
435 * This helper function allows drivers to get several clk
436 * consumers in one operation with management, the clks will
437 * automatically be freed when the device is unbound.
439 int __must_check devm_clk_bulk_get(struct device *dev, int num_clks,
440 struct clk_bulk_data *clks);
442 * devm_clk_bulk_get_optional - managed get multiple optional consumer clocks
443 * @dev: device for clock "consumer"
444 * @num_clks: the number of clk_bulk_data
445 * @clks: pointer to the clk_bulk_data table of consumer
447 * Behaves the same as devm_clk_bulk_get() except where there is no clock
448 * producer. In this case, instead of returning -ENOENT, the function returns
449 * NULL for given clk. It is assumed all clocks in clk_bulk_data are optional.
451 * Returns 0 if all clocks specified in clk_bulk_data table are obtained
452 * successfully or for any clk there was no clk provider available, otherwise
453 * returns valid IS_ERR() condition containing errno.
454 * The implementation uses @dev and @clk_bulk_data.id to determine the
455 * clock consumer, and thereby the clock producer.
456 * The clock returned is stored in each @clk_bulk_data.clk field.
458 * Drivers must assume that the clock source is not enabled.
460 * clk_bulk_get should not be called from within interrupt context.
462 int __must_check devm_clk_bulk_get_optional(struct device *dev, int num_clks,
463 struct clk_bulk_data *clks);
465 * devm_clk_bulk_get_all - managed get multiple clk consumers
466 * @dev: device for clock "consumer"
467 * @clks: pointer to the clk_bulk_data table of consumer
469 * Returns a positive value for the number of clocks obtained while the
470 * clock references are stored in the clk_bulk_data table in @clks field.
471 * Returns 0 if there're none and a negative value if something failed.
473 * This helper function allows drivers to get several clk
474 * consumers in one operation with management, the clks will
475 * automatically be freed when the device is unbound.
478 int __must_check devm_clk_bulk_get_all(struct device *dev,
479 struct clk_bulk_data **clks);
482 * devm_clk_get - lookup and obtain a managed reference to a clock producer.
483 * @dev: device for clock "consumer"
484 * @id: clock consumer ID
486 * Returns a struct clk corresponding to the clock producer, or
487 * valid IS_ERR() condition containing errno. The implementation
488 * uses @dev and @id to determine the clock consumer, and thereby
489 * the clock producer. (IOW, @id may be identical strings, but
490 * clk_get may return different clock producers depending on @dev.)
492 * Drivers must assume that the clock source is not enabled.
494 * devm_clk_get should not be called from within interrupt context.
496 * The clock will automatically be freed when the device is unbound
499 struct clk *devm_clk_get(struct device *dev, const char *id);
502 * devm_clk_get_prepared - devm_clk_get() + clk_prepare()
503 * @dev: device for clock "consumer"
504 * @id: clock consumer ID
506 * Context: May sleep.
508 * Return: a struct clk corresponding to the clock producer, or
509 * valid IS_ERR() condition containing errno. The implementation
510 * uses @dev and @id to determine the clock consumer, and thereby
511 * the clock producer. (IOW, @id may be identical strings, but
512 * clk_get may return different clock producers depending on @dev.)
514 * The returned clk (if valid) is prepared. Drivers must however assume
515 * that the clock is not enabled.
517 * The clock will automatically be unprepared and freed when the device
518 * is unbound from the bus.
520 struct clk *devm_clk_get_prepared(struct device *dev, const char *id);
523 * devm_clk_get_enabled - devm_clk_get() + clk_prepare_enable()
524 * @dev: device for clock "consumer"
525 * @id: clock consumer ID
527 * Context: May sleep.
529 * Return: a struct clk corresponding to the clock producer, or
530 * valid IS_ERR() condition containing errno. The implementation
531 * uses @dev and @id to determine the clock consumer, and thereby
532 * the clock producer. (IOW, @id may be identical strings, but
533 * clk_get may return different clock producers depending on @dev.)
535 * The returned clk (if valid) is prepared and enabled.
537 * The clock will automatically be disabled, unprepared and freed
538 * when the device is unbound from the bus.
540 struct clk *devm_clk_get_enabled(struct device *dev, const char *id);
543 * devm_clk_get_optional - lookup and obtain a managed reference to an optional
545 * @dev: device for clock "consumer"
546 * @id: clock consumer ID
548 * Behaves the same as devm_clk_get() except where there is no clock producer.
549 * In this case, instead of returning -ENOENT, the function returns NULL.
551 struct clk *devm_clk_get_optional(struct device *dev, const char *id);
554 * devm_clk_get_optional_prepared - devm_clk_get_optional() + clk_prepare()
555 * @dev: device for clock "consumer"
556 * @id: clock consumer ID
558 * Context: May sleep.
560 * Return: a struct clk corresponding to the clock producer, or
561 * valid IS_ERR() condition containing errno. The implementation
562 * uses @dev and @id to determine the clock consumer, and thereby
563 * the clock producer. If no such clk is found, it returns NULL
564 * which serves as a dummy clk. That's the only difference compared
565 * to devm_clk_get_prepared().
567 * The returned clk (if valid) is prepared. Drivers must however
568 * assume that the clock is not enabled.
570 * The clock will automatically be unprepared and freed when the
571 * device is unbound from the bus.
573 struct clk *devm_clk_get_optional_prepared(struct device *dev, const char *id);
576 * devm_clk_get_optional_enabled - devm_clk_get_optional() +
577 * clk_prepare_enable()
578 * @dev: device for clock "consumer"
579 * @id: clock consumer ID
581 * Context: May sleep.
583 * Return: a struct clk corresponding to the clock producer, or
584 * valid IS_ERR() condition containing errno. The implementation
585 * uses @dev and @id to determine the clock consumer, and thereby
586 * the clock producer. If no such clk is found, it returns NULL
587 * which serves as a dummy clk. That's the only difference compared
588 * to devm_clk_get_enabled().
590 * The returned clk (if valid) is prepared and enabled.
592 * The clock will automatically be disabled, unprepared and freed
593 * when the device is unbound from the bus.
595 struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id);
598 * devm_get_clk_from_child - lookup and obtain a managed reference to a
599 * clock producer from child node.
600 * @dev: device for clock "consumer"
601 * @np: pointer to clock consumer node
602 * @con_id: clock consumer ID
604 * This function parses the clocks, and uses them to look up the
605 * struct clk from the registered list of clock providers by using
608 * The clock will automatically be freed when the device is unbound
611 struct clk *devm_get_clk_from_child(struct device *dev,
612 struct device_node *np, const char *con_id);
615 * clk_enable - inform the system when the clock source should be running.
618 * If the clock can not be enabled/disabled, this should return success.
620 * May be called from atomic contexts.
622 * Returns success (0) or negative errno.
624 int clk_enable(struct clk *clk);
627 * clk_bulk_enable - inform the system when the set of clks should be running.
628 * @num_clks: the number of clk_bulk_data
629 * @clks: the clk_bulk_data table of consumer
631 * May be called from atomic contexts.
633 * Returns success (0) or negative errno.
635 int __must_check clk_bulk_enable(int num_clks,
636 const struct clk_bulk_data *clks);
639 * clk_disable - inform the system when the clock source is no longer required.
642 * Inform the system that a clock source is no longer required by
643 * a driver and may be shut down.
645 * May be called from atomic contexts.
647 * Implementation detail: if the clock source is shared between
648 * multiple drivers, clk_enable() calls must be balanced by the
649 * same number of clk_disable() calls for the clock source to be
652 void clk_disable(struct clk *clk);
655 * clk_bulk_disable - inform the system when the set of clks is no
657 * @num_clks: the number of clk_bulk_data
658 * @clks: the clk_bulk_data table of consumer
660 * Inform the system that a set of clks is no longer required by
661 * a driver and may be shut down.
663 * May be called from atomic contexts.
665 * Implementation detail: if the set of clks is shared between
666 * multiple drivers, clk_bulk_enable() calls must be balanced by the
667 * same number of clk_bulk_disable() calls for the clock source to be
670 void clk_bulk_disable(int num_clks, const struct clk_bulk_data *clks);
673 * clk_get_rate - obtain the current clock rate (in Hz) for a clock source.
674 * This is only valid once the clock source has been enabled.
677 unsigned long clk_get_rate(struct clk *clk);
680 * clk_put - "free" the clock source
683 * Note: drivers must ensure that all clk_enable calls made on this
684 * clock source are balanced by clk_disable calls prior to calling
687 * clk_put should not be called from within interrupt context.
689 void clk_put(struct clk *clk);
692 * clk_bulk_put - "free" the clock source
693 * @num_clks: the number of clk_bulk_data
694 * @clks: the clk_bulk_data table of consumer
696 * Note: drivers must ensure that all clk_bulk_enable calls made on this
697 * clock source are balanced by clk_bulk_disable calls prior to calling
700 * clk_bulk_put should not be called from within interrupt context.
702 void clk_bulk_put(int num_clks, struct clk_bulk_data *clks);
705 * clk_bulk_put_all - "free" all the clock source
706 * @num_clks: the number of clk_bulk_data
707 * @clks: the clk_bulk_data table of consumer
709 * Note: drivers must ensure that all clk_bulk_enable calls made on this
710 * clock source are balanced by clk_bulk_disable calls prior to calling
713 * clk_bulk_put_all should not be called from within interrupt context.
715 void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks);
718 * devm_clk_put - "free" a managed clock source
719 * @dev: device used to acquire the clock
720 * @clk: clock source acquired with devm_clk_get()
722 * Note: drivers must ensure that all clk_enable calls made on this
723 * clock source are balanced by clk_disable calls prior to calling
726 * clk_put should not be called from within interrupt context.
728 void devm_clk_put(struct device *dev, struct clk *clk);
731 * The remaining APIs are optional for machine class support.
736 * clk_round_rate - adjust a rate to the exact rate a clock can provide
738 * @rate: desired clock rate in Hz
740 * This answers the question "if I were to pass @rate to clk_set_rate(),
741 * what clock rate would I end up with?" without changing the hardware
742 * in any way. In other words:
744 * rate = clk_round_rate(clk, r);
748 * clk_set_rate(clk, r);
749 * rate = clk_get_rate(clk);
751 * are equivalent except the former does not modify the clock hardware
754 * Returns rounded clock rate in Hz, or negative errno.
756 long clk_round_rate(struct clk *clk, unsigned long rate);
759 * clk_set_rate - set the clock rate for a clock source
761 * @rate: desired clock rate in Hz
763 * Updating the rate starts at the top-most affected clock and then
764 * walks the tree down to the bottom-most clock that needs updating.
766 * Returns success (0) or negative errno.
768 int clk_set_rate(struct clk *clk, unsigned long rate);
771 * clk_set_rate_exclusive- set the clock rate and claim exclusivity over
774 * @rate: desired clock rate in Hz
776 * This helper function allows drivers to atomically set the rate of a producer
777 * and claim exclusivity over the rate control of the producer.
779 * It is essentially a combination of clk_set_rate() and
780 * clk_rate_exclusite_get(). Caller must balance this call with a call to
781 * clk_rate_exclusive_put()
783 * Returns success (0) or negative errno.
785 int clk_set_rate_exclusive(struct clk *clk, unsigned long rate);
788 * clk_has_parent - check if a clock is a possible parent for another
790 * @parent: parent clock source
792 * This function can be used in drivers that need to check that a clock can be
793 * the parent of another without actually changing the parent.
795 * Returns true if @parent is a possible parent for @clk, false otherwise.
797 bool clk_has_parent(struct clk *clk, struct clk *parent);
800 * clk_set_rate_range - set a rate range for a clock source
802 * @min: desired minimum clock rate in Hz, inclusive
803 * @max: desired maximum clock rate in Hz, inclusive
805 * Returns success (0) or negative errno.
807 int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max);
810 * clk_set_min_rate - set a minimum clock rate for a clock source
812 * @rate: desired minimum clock rate in Hz, inclusive
814 * Returns success (0) or negative errno.
816 int clk_set_min_rate(struct clk *clk, unsigned long rate);
819 * clk_set_max_rate - set a maximum clock rate for a clock source
821 * @rate: desired maximum clock rate in Hz, inclusive
823 * Returns success (0) or negative errno.
825 int clk_set_max_rate(struct clk *clk, unsigned long rate);
828 * clk_set_parent - set the parent clock source for this clock
830 * @parent: parent clock source
832 * Returns success (0) or negative errno.
834 int clk_set_parent(struct clk *clk, struct clk *parent);
837 * clk_get_parent - get the parent clock source for this clock
840 * Returns struct clk corresponding to parent clock source, or
841 * valid IS_ERR() condition containing errno.
843 struct clk *clk_get_parent(struct clk *clk);
846 * clk_get_sys - get a clock based upon the device name
847 * @dev_id: device name
848 * @con_id: connection ID
850 * Returns a struct clk corresponding to the clock producer, or
851 * valid IS_ERR() condition containing errno. The implementation
852 * uses @dev_id and @con_id to determine the clock consumer, and
853 * thereby the clock producer. In contrast to clk_get() this function
854 * takes the device name instead of the device itself for identification.
856 * Drivers must assume that the clock source is not enabled.
858 * clk_get_sys should not be called from within interrupt context.
860 struct clk *clk_get_sys(const char *dev_id, const char *con_id);
863 * clk_save_context - save clock context for poweroff
865 * Saves the context of the clock register for powerstates in which the
866 * contents of the registers will be lost. Occurs deep within the suspend
867 * code so locking is not necessary.
869 int clk_save_context(void);
872 * clk_restore_context - restore clock context after poweroff
874 * This occurs with all clocks enabled. Occurs deep within the resume code
875 * so locking is not necessary.
877 void clk_restore_context(void);
879 #else /* !CONFIG_HAVE_CLK */
881 static inline struct clk *clk_get(struct device *dev, const char *id)
886 static inline int __must_check clk_bulk_get(struct device *dev, int num_clks,
887 struct clk_bulk_data *clks)
892 static inline int __must_check clk_bulk_get_optional(struct device *dev,
893 int num_clks, struct clk_bulk_data *clks)
898 static inline int __must_check clk_bulk_get_all(struct device *dev,
899 struct clk_bulk_data **clks)
904 static inline struct clk *devm_clk_get(struct device *dev, const char *id)
909 static inline struct clk *devm_clk_get_prepared(struct device *dev,
915 static inline struct clk *devm_clk_get_enabled(struct device *dev,
921 static inline struct clk *devm_clk_get_optional(struct device *dev,
927 static inline struct clk *devm_clk_get_optional_prepared(struct device *dev,
933 static inline struct clk *devm_clk_get_optional_enabled(struct device *dev,
939 static inline int __must_check devm_clk_bulk_get(struct device *dev, int num_clks,
940 struct clk_bulk_data *clks)
945 static inline int __must_check devm_clk_bulk_get_optional(struct device *dev,
946 int num_clks, struct clk_bulk_data *clks)
951 static inline int __must_check devm_clk_bulk_get_all(struct device *dev,
952 struct clk_bulk_data **clks)
958 static inline struct clk *devm_get_clk_from_child(struct device *dev,
959 struct device_node *np, const char *con_id)
964 static inline void clk_put(struct clk *clk) {}
966 static inline void clk_bulk_put(int num_clks, struct clk_bulk_data *clks) {}
968 static inline void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks) {}
970 static inline void devm_clk_put(struct device *dev, struct clk *clk) {}
972 static inline int clk_enable(struct clk *clk)
977 static inline int __must_check clk_bulk_enable(int num_clks,
978 const struct clk_bulk_data *clks)
983 static inline void clk_disable(struct clk *clk) {}
986 static inline void clk_bulk_disable(int num_clks,
987 const struct clk_bulk_data *clks) {}
989 static inline unsigned long clk_get_rate(struct clk *clk)
994 static inline int clk_set_rate(struct clk *clk, unsigned long rate)
999 static inline int clk_set_rate_exclusive(struct clk *clk, unsigned long rate)
1004 static inline long clk_round_rate(struct clk *clk, unsigned long rate)
1009 static inline bool clk_has_parent(struct clk *clk, struct clk *parent)
1014 static inline int clk_set_rate_range(struct clk *clk, unsigned long min,
1020 static inline int clk_set_min_rate(struct clk *clk, unsigned long rate)
1025 static inline int clk_set_max_rate(struct clk *clk, unsigned long rate)
1030 static inline int clk_set_parent(struct clk *clk, struct clk *parent)
1035 static inline struct clk *clk_get_parent(struct clk *clk)
1040 static inline struct clk *clk_get_sys(const char *dev_id, const char *con_id)
1045 static inline int clk_save_context(void)
1050 static inline void clk_restore_context(void) {}
1054 /* clk_prepare_enable helps cases using clk_enable in non-atomic context. */
1055 static inline int clk_prepare_enable(struct clk *clk)
1059 ret = clk_prepare(clk);
1062 ret = clk_enable(clk);
1069 /* clk_disable_unprepare helps cases using clk_disable in non-atomic context. */
1070 static inline void clk_disable_unprepare(struct clk *clk)
1076 static inline int __must_check
1077 clk_bulk_prepare_enable(int num_clks, const struct clk_bulk_data *clks)
1081 ret = clk_bulk_prepare(num_clks, clks);
1084 ret = clk_bulk_enable(num_clks, clks);
1086 clk_bulk_unprepare(num_clks, clks);
1091 static inline void clk_bulk_disable_unprepare(int num_clks,
1092 const struct clk_bulk_data *clks)
1094 clk_bulk_disable(num_clks, clks);
1095 clk_bulk_unprepare(num_clks, clks);
1099 * clk_get_optional - lookup and obtain a reference to an optional clock
1101 * @dev: device for clock "consumer"
1102 * @id: clock consumer ID
1104 * Behaves the same as clk_get() except where there is no clock producer. In
1105 * this case, instead of returning -ENOENT, the function returns NULL.
1107 static inline struct clk *clk_get_optional(struct device *dev, const char *id)
1109 struct clk *clk = clk_get(dev, id);
1111 if (clk == ERR_PTR(-ENOENT))
1117 #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
1118 struct clk *of_clk_get(struct device_node *np, int index);
1119 struct clk *of_clk_get_by_name(struct device_node *np, const char *name);
1120 struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec);
1122 static inline struct clk *of_clk_get(struct device_node *np, int index)
1124 return ERR_PTR(-ENOENT);
1126 static inline struct clk *of_clk_get_by_name(struct device_node *np,
1129 return ERR_PTR(-ENOENT);
1131 static inline struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
1133 return ERR_PTR(-ENOENT);