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);
188 static inline int clk_notifier_register(struct clk *clk,
189 struct notifier_block *nb)
194 static inline int clk_notifier_unregister(struct clk *clk,
195 struct notifier_block *nb)
200 static inline int devm_clk_notifier_register(struct device *dev,
202 struct notifier_block *nb)
207 static inline long clk_get_accuracy(struct clk *clk)
212 static inline long clk_set_phase(struct clk *clk, int phase)
217 static inline long clk_get_phase(struct clk *clk)
222 static inline int clk_set_duty_cycle(struct clk *clk, unsigned int num,
228 static inline unsigned int clk_get_scaled_duty_cycle(struct clk *clk,
234 static inline bool clk_is_match(const struct clk *p, const struct clk *q)
241 #ifdef CONFIG_HAVE_CLK_PREPARE
243 * clk_prepare - prepare a clock source
246 * This prepares the clock source for use.
248 * Must not be called from within atomic context.
250 int clk_prepare(struct clk *clk);
251 int __must_check clk_bulk_prepare(int num_clks,
252 const struct clk_bulk_data *clks);
255 * clk_is_enabled_when_prepared - indicate if preparing a clock also enables it.
258 * Returns true if clk_prepare() implicitly enables the clock, effectively
259 * making clk_enable()/clk_disable() no-ops, false otherwise.
261 * This is of interest mainly to the power management code where actually
262 * disabling the clock also requires unpreparing it to have any material
265 * Regardless of the value returned here, the caller must always invoke
266 * clk_enable() or clk_prepare_enable() and counterparts for usage counts
269 bool clk_is_enabled_when_prepared(struct clk *clk);
271 static inline int clk_prepare(struct clk *clk)
277 static inline int __must_check
278 clk_bulk_prepare(int num_clks, const struct clk_bulk_data *clks)
284 static inline bool clk_is_enabled_when_prepared(struct clk *clk)
291 * clk_unprepare - undo preparation of a clock source
294 * This undoes a previously prepared clock. The caller must balance
295 * the number of prepare and unprepare calls.
297 * Must not be called from within atomic context.
299 #ifdef CONFIG_HAVE_CLK_PREPARE
300 void clk_unprepare(struct clk *clk);
301 void clk_bulk_unprepare(int num_clks, const struct clk_bulk_data *clks);
303 static inline void clk_unprepare(struct clk *clk)
307 static inline void clk_bulk_unprepare(int num_clks,
308 const struct clk_bulk_data *clks)
314 #ifdef CONFIG_HAVE_CLK
316 * clk_get - lookup and obtain a reference to a clock producer.
317 * @dev: device for clock "consumer"
318 * @id: clock consumer ID
320 * Returns a struct clk corresponding to the clock producer, or
321 * valid IS_ERR() condition containing errno. The implementation
322 * uses @dev and @id to determine the clock consumer, and thereby
323 * the clock producer. (IOW, @id may be identical strings, but
324 * clk_get may return different clock producers depending on @dev.)
326 * Drivers must assume that the clock source is not enabled.
328 * clk_get should not be called from within interrupt context.
330 struct clk *clk_get(struct device *dev, const char *id);
333 * clk_bulk_get - lookup and obtain a number of references to clock producer.
334 * @dev: device for clock "consumer"
335 * @num_clks: the number of clk_bulk_data
336 * @clks: the clk_bulk_data table of consumer
338 * This helper function allows drivers to get several clk consumers in one
339 * operation. If any of the clk cannot be acquired then any clks
340 * that were obtained will be freed before returning to the caller.
342 * Returns 0 if all clocks specified in clk_bulk_data table are obtained
343 * successfully, or valid IS_ERR() condition containing errno.
344 * The implementation uses @dev and @clk_bulk_data.id to determine the
345 * clock consumer, and thereby the clock producer.
346 * The clock returned is stored in each @clk_bulk_data.clk field.
348 * Drivers must assume that the clock source is not enabled.
350 * clk_bulk_get should not be called from within interrupt context.
352 int __must_check clk_bulk_get(struct device *dev, int num_clks,
353 struct clk_bulk_data *clks);
355 * clk_bulk_get_all - lookup and obtain all available references to clock
357 * @dev: device for clock "consumer"
358 * @clks: pointer to the clk_bulk_data table of consumer
360 * This helper function allows drivers to get all clk consumers in one
361 * operation. If any of the clk cannot be acquired then any clks
362 * that were obtained will be freed before returning to the caller.
364 * Returns a positive value for the number of clocks obtained while the
365 * clock references are stored in the clk_bulk_data table in @clks field.
366 * Returns 0 if there're none and a negative value if something failed.
368 * Drivers must assume that the clock source is not enabled.
370 * clk_bulk_get should not be called from within interrupt context.
372 int __must_check clk_bulk_get_all(struct device *dev,
373 struct clk_bulk_data **clks);
376 * clk_bulk_get_optional - lookup and obtain a number of references to clock producer
377 * @dev: device for clock "consumer"
378 * @num_clks: the number of clk_bulk_data
379 * @clks: the clk_bulk_data table of consumer
381 * Behaves the same as clk_bulk_get() except where there is no clock producer.
382 * In this case, instead of returning -ENOENT, the function returns 0 and
383 * NULL for a clk for which a clock producer could not be determined.
385 int __must_check clk_bulk_get_optional(struct device *dev, int num_clks,
386 struct clk_bulk_data *clks);
388 * devm_clk_bulk_get - managed get multiple clk consumers
389 * @dev: device for clock "consumer"
390 * @num_clks: the number of clk_bulk_data
391 * @clks: the clk_bulk_data table of consumer
393 * Return 0 on success, an errno on failure.
395 * This helper function allows drivers to get several clk
396 * consumers in one operation with management, the clks will
397 * automatically be freed when the device is unbound.
399 int __must_check devm_clk_bulk_get(struct device *dev, int num_clks,
400 struct clk_bulk_data *clks);
402 * devm_clk_bulk_get_optional - managed get multiple optional consumer clocks
403 * @dev: device for clock "consumer"
404 * @num_clks: the number of clk_bulk_data
405 * @clks: pointer to the clk_bulk_data table of consumer
407 * Behaves the same as devm_clk_bulk_get() except where there is no clock
408 * producer. In this case, instead of returning -ENOENT, the function returns
409 * NULL for given clk. It is assumed all clocks in clk_bulk_data are optional.
411 * Returns 0 if all clocks specified in clk_bulk_data table are obtained
412 * successfully or for any clk there was no clk provider available, otherwise
413 * returns valid IS_ERR() condition containing errno.
414 * The implementation uses @dev and @clk_bulk_data.id to determine the
415 * clock consumer, and thereby the clock producer.
416 * The clock returned is stored in each @clk_bulk_data.clk field.
418 * Drivers must assume that the clock source is not enabled.
420 * clk_bulk_get should not be called from within interrupt context.
422 int __must_check devm_clk_bulk_get_optional(struct device *dev, int num_clks,
423 struct clk_bulk_data *clks);
425 * devm_clk_bulk_get_all - managed get multiple clk consumers
426 * @dev: device for clock "consumer"
427 * @clks: pointer to the clk_bulk_data table of consumer
429 * Returns a positive value for the number of clocks obtained while the
430 * clock references are stored in the clk_bulk_data table in @clks field.
431 * Returns 0 if there're none and a negative value if something failed.
433 * This helper function allows drivers to get several clk
434 * consumers in one operation with management, the clks will
435 * automatically be freed when the device is unbound.
438 int __must_check devm_clk_bulk_get_all(struct device *dev,
439 struct clk_bulk_data **clks);
442 * devm_clk_get - lookup and obtain a managed reference to a clock producer.
443 * @dev: device for clock "consumer"
444 * @id: clock consumer ID
446 * Context: May sleep.
448 * Return: a struct clk corresponding to the clock producer, or
449 * valid IS_ERR() condition containing errno. The implementation
450 * uses @dev and @id to determine the clock consumer, and thereby
451 * the clock producer. (IOW, @id may be identical strings, but
452 * clk_get may return different clock producers depending on @dev.)
454 * Drivers must assume that the clock source is neither prepared nor
457 * The clock will automatically be freed when the device is unbound
460 struct clk *devm_clk_get(struct device *dev, const char *id);
463 * devm_clk_get_prepared - devm_clk_get() + clk_prepare()
464 * @dev: device for clock "consumer"
465 * @id: clock consumer ID
467 * Context: May sleep.
469 * Return: a struct clk corresponding to the clock producer, or
470 * valid IS_ERR() condition containing errno. The implementation
471 * uses @dev and @id to determine the clock consumer, and thereby
472 * the clock producer. (IOW, @id may be identical strings, but
473 * clk_get may return different clock producers depending on @dev.)
475 * The returned clk (if valid) is prepared. Drivers must however assume
476 * that the clock is not enabled.
478 * The clock will automatically be unprepared and freed when the device
479 * is unbound from the bus.
481 struct clk *devm_clk_get_prepared(struct device *dev, const char *id);
484 * devm_clk_get_enabled - devm_clk_get() + clk_prepare_enable()
485 * @dev: device for clock "consumer"
486 * @id: clock consumer ID
488 * Context: May sleep.
490 * Return: a struct clk corresponding to the clock producer, or
491 * valid IS_ERR() condition containing errno. The implementation
492 * uses @dev and @id to determine the clock consumer, and thereby
493 * the clock producer. (IOW, @id may be identical strings, but
494 * clk_get may return different clock producers depending on @dev.)
496 * The returned clk (if valid) is prepared and enabled.
498 * The clock will automatically be disabled, unprepared and freed
499 * when the device is unbound from the bus.
501 struct clk *devm_clk_get_enabled(struct device *dev, const char *id);
504 * devm_clk_get_optional - lookup and obtain a managed reference to an optional
506 * @dev: device for clock "consumer"
507 * @id: clock consumer ID
509 * Context: May sleep.
511 * Return: a struct clk corresponding to the clock producer, or
512 * valid IS_ERR() condition containing errno. The implementation
513 * uses @dev and @id to determine the clock consumer, and thereby
514 * the clock producer. If no such clk is found, it returns NULL
515 * which serves as a dummy clk. That's the only difference compared
518 * Drivers must assume that the clock source is neither prepared nor
521 * The clock will automatically be freed when the device is unbound
524 struct clk *devm_clk_get_optional(struct device *dev, const char *id);
527 * devm_clk_get_optional_prepared - devm_clk_get_optional() + clk_prepare()
528 * @dev: device for clock "consumer"
529 * @id: clock consumer ID
531 * Context: May sleep.
533 * Return: a struct clk corresponding to the clock producer, or
534 * valid IS_ERR() condition containing errno. The implementation
535 * uses @dev and @id to determine the clock consumer, and thereby
536 * the clock producer. If no such clk is found, it returns NULL
537 * which serves as a dummy clk. That's the only difference compared
538 * to devm_clk_get_prepared().
540 * The returned clk (if valid) is prepared. Drivers must however
541 * assume that the clock is not enabled.
543 * The clock will automatically be unprepared and freed when the
544 * device is unbound from the bus.
546 struct clk *devm_clk_get_optional_prepared(struct device *dev, const char *id);
549 * devm_clk_get_optional_enabled - devm_clk_get_optional() +
550 * clk_prepare_enable()
551 * @dev: device for clock "consumer"
552 * @id: clock consumer ID
554 * Context: May sleep.
556 * Return: a struct clk corresponding to the clock producer, or
557 * valid IS_ERR() condition containing errno. The implementation
558 * uses @dev and @id to determine the clock consumer, and thereby
559 * the clock producer. If no such clk is found, it returns NULL
560 * which serves as a dummy clk. That's the only difference compared
561 * to devm_clk_get_enabled().
563 * The returned clk (if valid) is prepared and enabled.
565 * The clock will automatically be disabled, unprepared and freed
566 * when the device is unbound from the bus.
568 struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id);
571 * devm_get_clk_from_child - lookup and obtain a managed reference to a
572 * clock producer from child node.
573 * @dev: device for clock "consumer"
574 * @np: pointer to clock consumer node
575 * @con_id: clock consumer ID
577 * This function parses the clocks, and uses them to look up the
578 * struct clk from the registered list of clock providers by using
581 * The clock will automatically be freed when the device is unbound
584 struct clk *devm_get_clk_from_child(struct device *dev,
585 struct device_node *np, const char *con_id);
587 * clk_rate_exclusive_get - get exclusivity over the rate control of a
591 * This function allows drivers to get exclusive control over the rate of a
592 * provider. It prevents any other consumer to execute, even indirectly,
593 * opereation which could alter the rate of the provider or cause glitches
595 * If exlusivity is claimed more than once on clock, even by the same driver,
596 * the rate effectively gets locked as exclusivity can't be preempted.
598 * Must not be called from within atomic context.
600 * Returns success (0) or negative errno.
602 int clk_rate_exclusive_get(struct clk *clk);
605 * clk_rate_exclusive_put - release exclusivity over the rate control of a
609 * This function allows drivers to release the exclusivity it previously got
610 * from clk_rate_exclusive_get()
612 * The caller must balance the number of clk_rate_exclusive_get() and
613 * clk_rate_exclusive_put() calls.
615 * Must not be called from within atomic context.
617 void clk_rate_exclusive_put(struct clk *clk);
620 * clk_enable - inform the system when the clock source should be running.
623 * If the clock can not be enabled/disabled, this should return success.
625 * May be called from atomic contexts.
627 * Returns success (0) or negative errno.
629 int clk_enable(struct clk *clk);
632 * clk_bulk_enable - inform the system when the set of clks should be running.
633 * @num_clks: the number of clk_bulk_data
634 * @clks: the clk_bulk_data table of consumer
636 * May be called from atomic contexts.
638 * Returns success (0) or negative errno.
640 int __must_check clk_bulk_enable(int num_clks,
641 const struct clk_bulk_data *clks);
644 * clk_disable - inform the system when the clock source is no longer required.
647 * Inform the system that a clock source is no longer required by
648 * a driver and may be shut down.
650 * May be called from atomic contexts.
652 * Implementation detail: if the clock source is shared between
653 * multiple drivers, clk_enable() calls must be balanced by the
654 * same number of clk_disable() calls for the clock source to be
657 void clk_disable(struct clk *clk);
660 * clk_bulk_disable - inform the system when the set of clks is no
662 * @num_clks: the number of clk_bulk_data
663 * @clks: the clk_bulk_data table of consumer
665 * Inform the system that a set of clks is no longer required by
666 * a driver and may be shut down.
668 * May be called from atomic contexts.
670 * Implementation detail: if the set of clks is shared between
671 * multiple drivers, clk_bulk_enable() calls must be balanced by the
672 * same number of clk_bulk_disable() calls for the clock source to be
675 void clk_bulk_disable(int num_clks, const struct clk_bulk_data *clks);
678 * clk_get_rate - obtain the current clock rate (in Hz) for a clock source.
679 * This is only valid once the clock source has been enabled.
682 unsigned long clk_get_rate(struct clk *clk);
685 * clk_put - "free" the clock source
688 * Note: drivers must ensure that all clk_enable calls made on this
689 * clock source are balanced by clk_disable calls prior to calling
692 * clk_put should not be called from within interrupt context.
694 void clk_put(struct clk *clk);
697 * clk_bulk_put - "free" the clock source
698 * @num_clks: the number of clk_bulk_data
699 * @clks: the clk_bulk_data table of consumer
701 * Note: drivers must ensure that all clk_bulk_enable calls made on this
702 * clock source are balanced by clk_bulk_disable calls prior to calling
705 * clk_bulk_put should not be called from within interrupt context.
707 void clk_bulk_put(int num_clks, struct clk_bulk_data *clks);
710 * clk_bulk_put_all - "free" all the clock source
711 * @num_clks: the number of clk_bulk_data
712 * @clks: the clk_bulk_data table of consumer
714 * Note: drivers must ensure that all clk_bulk_enable calls made on this
715 * clock source are balanced by clk_bulk_disable calls prior to calling
718 * clk_bulk_put_all should not be called from within interrupt context.
720 void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks);
723 * devm_clk_put - "free" a managed clock source
724 * @dev: device used to acquire the clock
725 * @clk: clock source acquired with devm_clk_get()
727 * Note: drivers must ensure that all clk_enable calls made on this
728 * clock source are balanced by clk_disable calls prior to calling
731 * clk_put should not be called from within interrupt context.
733 void devm_clk_put(struct device *dev, struct clk *clk);
736 * The remaining APIs are optional for machine class support.
741 * clk_round_rate - adjust a rate to the exact rate a clock can provide
743 * @rate: desired clock rate in Hz
745 * This answers the question "if I were to pass @rate to clk_set_rate(),
746 * what clock rate would I end up with?" without changing the hardware
747 * in any way. In other words:
749 * rate = clk_round_rate(clk, r);
753 * clk_set_rate(clk, r);
754 * rate = clk_get_rate(clk);
756 * are equivalent except the former does not modify the clock hardware
759 * Returns rounded clock rate in Hz, or negative errno.
761 long clk_round_rate(struct clk *clk, unsigned long rate);
764 * clk_set_rate - set the clock rate for a clock source
766 * @rate: desired clock rate in Hz
768 * Updating the rate starts at the top-most affected clock and then
769 * walks the tree down to the bottom-most clock that needs updating.
771 * Returns success (0) or negative errno.
773 int clk_set_rate(struct clk *clk, unsigned long rate);
776 * clk_set_rate_exclusive- set the clock rate and claim exclusivity over
779 * @rate: desired clock rate in Hz
781 * This helper function allows drivers to atomically set the rate of a producer
782 * and claim exclusivity over the rate control of the producer.
784 * It is essentially a combination of clk_set_rate() and
785 * clk_rate_exclusite_get(). Caller must balance this call with a call to
786 * clk_rate_exclusive_put()
788 * Returns success (0) or negative errno.
790 int clk_set_rate_exclusive(struct clk *clk, unsigned long rate);
793 * clk_has_parent - check if a clock is a possible parent for another
795 * @parent: parent clock source
797 * This function can be used in drivers that need to check that a clock can be
798 * the parent of another without actually changing the parent.
800 * Returns true if @parent is a possible parent for @clk, false otherwise.
802 bool clk_has_parent(struct clk *clk, struct clk *parent);
805 * clk_set_rate_range - set a rate range for a clock source
807 * @min: desired minimum clock rate in Hz, inclusive
808 * @max: desired maximum clock rate in Hz, inclusive
810 * Returns success (0) or negative errno.
812 int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max);
815 * clk_set_min_rate - set a minimum clock rate for a clock source
817 * @rate: desired minimum clock rate in Hz, inclusive
819 * Returns success (0) or negative errno.
821 int clk_set_min_rate(struct clk *clk, unsigned long rate);
824 * clk_set_max_rate - set a maximum clock rate for a clock source
826 * @rate: desired maximum clock rate in Hz, inclusive
828 * Returns success (0) or negative errno.
830 int clk_set_max_rate(struct clk *clk, unsigned long rate);
833 * clk_set_parent - set the parent clock source for this clock
835 * @parent: parent clock source
837 * Returns success (0) or negative errno.
839 int clk_set_parent(struct clk *clk, struct clk *parent);
842 * clk_get_parent - get the parent clock source for this clock
845 * Returns struct clk corresponding to parent clock source, or
846 * valid IS_ERR() condition containing errno.
848 struct clk *clk_get_parent(struct clk *clk);
851 * clk_get_sys - get a clock based upon the device name
852 * @dev_id: device name
853 * @con_id: connection ID
855 * Returns a struct clk corresponding to the clock producer, or
856 * valid IS_ERR() condition containing errno. The implementation
857 * uses @dev_id and @con_id to determine the clock consumer, and
858 * thereby the clock producer. In contrast to clk_get() this function
859 * takes the device name instead of the device itself for identification.
861 * Drivers must assume that the clock source is not enabled.
863 * clk_get_sys should not be called from within interrupt context.
865 struct clk *clk_get_sys(const char *dev_id, const char *con_id);
868 * clk_save_context - save clock context for poweroff
870 * Saves the context of the clock register for powerstates in which the
871 * contents of the registers will be lost. Occurs deep within the suspend
872 * code so locking is not necessary.
874 int clk_save_context(void);
877 * clk_restore_context - restore clock context after poweroff
879 * This occurs with all clocks enabled. Occurs deep within the resume code
880 * so locking is not necessary.
882 void clk_restore_context(void);
884 #else /* !CONFIG_HAVE_CLK */
886 static inline struct clk *clk_get(struct device *dev, const char *id)
891 static inline int __must_check clk_bulk_get(struct device *dev, int num_clks,
892 struct clk_bulk_data *clks)
897 static inline int __must_check clk_bulk_get_optional(struct device *dev,
898 int num_clks, struct clk_bulk_data *clks)
903 static inline int __must_check clk_bulk_get_all(struct device *dev,
904 struct clk_bulk_data **clks)
909 static inline struct clk *devm_clk_get(struct device *dev, const char *id)
914 static inline struct clk *devm_clk_get_prepared(struct device *dev,
920 static inline struct clk *devm_clk_get_enabled(struct device *dev,
926 static inline struct clk *devm_clk_get_optional(struct device *dev,
932 static inline struct clk *devm_clk_get_optional_prepared(struct device *dev,
938 static inline struct clk *devm_clk_get_optional_enabled(struct device *dev,
944 static inline int __must_check devm_clk_bulk_get(struct device *dev, int num_clks,
945 struct clk_bulk_data *clks)
950 static inline int __must_check devm_clk_bulk_get_optional(struct device *dev,
951 int num_clks, struct clk_bulk_data *clks)
956 static inline int __must_check devm_clk_bulk_get_all(struct device *dev,
957 struct clk_bulk_data **clks)
963 static inline struct clk *devm_get_clk_from_child(struct device *dev,
964 struct device_node *np, const char *con_id)
969 static inline void clk_put(struct clk *clk) {}
971 static inline void clk_bulk_put(int num_clks, struct clk_bulk_data *clks) {}
973 static inline void clk_bulk_put_all(int num_clks, struct clk_bulk_data *clks) {}
975 static inline void devm_clk_put(struct device *dev, struct clk *clk) {}
978 static inline int clk_rate_exclusive_get(struct clk *clk)
983 static inline void clk_rate_exclusive_put(struct clk *clk) {}
985 static inline int clk_enable(struct clk *clk)
990 static inline int __must_check clk_bulk_enable(int num_clks,
991 const struct clk_bulk_data *clks)
996 static inline void clk_disable(struct clk *clk) {}
999 static inline void clk_bulk_disable(int num_clks,
1000 const struct clk_bulk_data *clks) {}
1002 static inline unsigned long clk_get_rate(struct clk *clk)
1007 static inline int clk_set_rate(struct clk *clk, unsigned long rate)
1012 static inline int clk_set_rate_exclusive(struct clk *clk, unsigned long rate)
1017 static inline long clk_round_rate(struct clk *clk, unsigned long rate)
1022 static inline bool clk_has_parent(struct clk *clk, struct clk *parent)
1027 static inline int clk_set_rate_range(struct clk *clk, unsigned long min,
1033 static inline int clk_set_min_rate(struct clk *clk, unsigned long rate)
1038 static inline int clk_set_max_rate(struct clk *clk, unsigned long rate)
1043 static inline int clk_set_parent(struct clk *clk, struct clk *parent)
1048 static inline struct clk *clk_get_parent(struct clk *clk)
1053 static inline struct clk *clk_get_sys(const char *dev_id, const char *con_id)
1058 static inline int clk_save_context(void)
1063 static inline void clk_restore_context(void) {}
1067 /* clk_prepare_enable helps cases using clk_enable in non-atomic context. */
1068 static inline int clk_prepare_enable(struct clk *clk)
1072 ret = clk_prepare(clk);
1075 ret = clk_enable(clk);
1082 /* clk_disable_unprepare helps cases using clk_disable in non-atomic context. */
1083 static inline void clk_disable_unprepare(struct clk *clk)
1089 static inline int __must_check
1090 clk_bulk_prepare_enable(int num_clks, const struct clk_bulk_data *clks)
1094 ret = clk_bulk_prepare(num_clks, clks);
1097 ret = clk_bulk_enable(num_clks, clks);
1099 clk_bulk_unprepare(num_clks, clks);
1104 static inline void clk_bulk_disable_unprepare(int num_clks,
1105 const struct clk_bulk_data *clks)
1107 clk_bulk_disable(num_clks, clks);
1108 clk_bulk_unprepare(num_clks, clks);
1112 * clk_drop_range - Reset any range set on that clock
1113 * @clk: clock source
1115 * Returns success (0) or negative errno.
1117 static inline int clk_drop_range(struct clk *clk)
1119 return clk_set_rate_range(clk, 0, ULONG_MAX);
1123 * clk_get_optional - lookup and obtain a reference to an optional clock
1125 * @dev: device for clock "consumer"
1126 * @id: clock consumer ID
1128 * Behaves the same as clk_get() except where there is no clock producer. In
1129 * this case, instead of returning -ENOENT, the function returns NULL.
1131 static inline struct clk *clk_get_optional(struct device *dev, const char *id)
1133 struct clk *clk = clk_get(dev, id);
1135 if (clk == ERR_PTR(-ENOENT))
1141 #if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
1142 struct clk *of_clk_get(struct device_node *np, int index);
1143 struct clk *of_clk_get_by_name(struct device_node *np, const char *name);
1144 struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec);
1146 static inline struct clk *of_clk_get(struct device_node *np, int index)
1148 return ERR_PTR(-ENOENT);
1150 static inline struct clk *of_clk_get_by_name(struct device_node *np,
1153 return ERR_PTR(-ENOENT);
1155 static inline struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
1157 return ERR_PTR(-ENOENT);