include/linux/clk.h

1 /* SPDX-License-Identifier: GPL-2.0-only */
7  *  Copyright (C) 2011-2012 Linaro Ltd <mturquette@linaro.org>
24  * PRE_RATE_CHANGE - called immediately before the clk rate is changed,
35  * POST_RATE_CHANGE - called after the clk rate change has successfully
44  * struct clk_notifier - associate a clk with a notifier
61  * struct clk_notifier_data - rate data to pass to the notifier callback
66  * For a pre-notifier, old_rate is the clk's rate before this rate
68  * post-notifier, old_rate and new_rate are both set to the clk's
78  * struct clk_bulk_data - Data used for bulk clk operations.
95  * clk_notifier_register - register a clock rate-change notifier callback
106  * clk_notifier_unregister - unregister a clock rate-change notifier callback
113  * devm_clk_notifier_register - register a managed rate-change notifier callback
118  * Returns 0 on success, -EERROR otherwise
124  * clk_get_accuracy - obtain the clock accuracy in ppb (parts per billion)
134  * clk_set_phase - adjust the phase shift of a clock signal
138  * Shifts the phase of a clock signal by the specified degrees. Returns 0 on
139  * success, -EERROR otherwise.
144  * clk_get_phase - return the phase shift of a clock signal
147  * Returns the phase shift of a clock node in degrees, otherwise returns
148  * -EERROR.
153  * clk_set_duty_cycle - adjust the duty cycle ratio of a clock signal
159  * success, -EERROR otherwise.
164  * clk_get_scaled_duty_cycle - return the duty cycle ratio of a clock signal
169  * returns -EERROR.
174  * clk_is_match - check if two clk's point to the same hardware clock
187  * clk_rate_exclusive_get - get exclusivity over the rate control of a
200  * Returns success (0) or negative errno.
205  * clk_rate_exclusive_put - release exclusivity over the rate control of a
224 	return -ENOTSUPP;  in clk_notifier_register()
230 	return -ENOTSUPP;  in clk_notifier_unregister()
237 	return -ENOTSUPP;  in devm_clk_notifier_register()
242 	return -ENOTSUPP;  in clk_get_accuracy()
245 static inline long clk_set_phase(struct clk *clk, int phase)  in clk_set_phase()  argument
247 	return -ENOTSUPP;  in clk_set_phase()
252 	return -ENOTSUPP;  in clk_get_phase()
258 	return -ENOTSUPP;  in clk_set_duty_cycle()
283  * clk_prepare - prepare a clock source
295  * clk_is_enabled_when_prepared - indicate if preparing a clock also enables it.
299  * making clk_enable()/clk_disable() no-ops, false otherwise.
331  * clk_unprepare - undo preparation of a clock source
356  * clk_get - lookup and obtain a reference to a clock producer.
373  * clk_bulk_get - lookup and obtain a number of references to clock producer.
395  * clk_bulk_get_all - lookup and obtain all available references to clock
406  * Returns 0 if there're none and a negative value if something failed.
416  * clk_bulk_get_optional - lookup and obtain a number of references to clock producer
422  * In this case, instead of returning -ENOENT, the function returns 0 and
428  * devm_clk_bulk_get - managed get multiple clk consumers
442  * devm_clk_bulk_get_optional - managed get multiple optional consumer clocks
448  * producer.  In this case, instead of returning -ENOENT, the function returns
465  * devm_clk_bulk_get_all - managed get multiple clk consumers
471  * Returns 0 if there're none and a negative value if something failed.
482  * devm_clk_get - lookup and obtain a managed reference to a clock producer.
503  * devm_clk_get_prepared - devm_clk_get() + clk_prepare()
524  * devm_clk_get_enabled - devm_clk_get() + clk_prepare_enable()
544  * devm_clk_get_optional - lookup and obtain a managed reference to an optional
567  * devm_clk_get_optional_prepared - devm_clk_get_optional() + clk_prepare()
589  * devm_clk_get_optional_enabled - devm_clk_get_optional() +
611  * devm_get_clk_from_child - lookup and obtain a managed reference to a
628  * clk_enable - inform the system when the clock source should be running.
635  * Returns success (0) or negative errno.
640  * clk_bulk_enable - inform the system when the set of clks should be running.
646  * Returns success (0) or negative errno.
652  * clk_disable - inform the system when the clock source is no longer required.
668  * clk_bulk_disable - inform the system when the set of clks is no
686  * clk_get_rate - obtain the current clock rate (in Hz) for a clock source.
693  * clk_put	- "free" the clock source
705  * clk_bulk_put	- "free" the clock source
718  * clk_bulk_put_all - "free" all the clock source
731  * devm_clk_put	- "free" a managed clock source
749  * clk_round_rate - adjust a rate to the exact rate a clock can provide
767  * Returns rounded clock rate in Hz, or negative errno.
772  * clk_set_rate - set the clock rate for a clock source
776  * Updating the rate starts at the top-most affected clock and then
777  * walks the tree down to the bottom-most clock that needs updating.
779  * Returns success (0) or negative errno.
784  * clk_set_rate_exclusive- set the clock rate and claim exclusivity over
796  * Returns success (0) or negative errno.
801  * clk_has_parent - check if a clock is a possible parent for another
813  * clk_set_rate_range - set a rate range for a clock source
818  * Returns success (0) or negative errno.
823  * clk_set_min_rate - set a minimum clock rate for a clock source
827  * Returns success (0) or negative errno.
832  * clk_set_max_rate - set a maximum clock rate for a clock source
836  * Returns success (0) or negative errno.
841  * clk_set_parent - set the parent clock source for this clock
845  * Returns success (0) or negative errno.
850  * clk_get_parent - get the parent clock source for this clock
859  * clk_get_sys - get a clock based upon the device name
876  * clk_save_context - save clock context for poweroff
885  * clk_restore_context - restore clock context after poweroff
1067 /* clk_prepare_enable helps cases using clk_enable in non-atomic context. */
1082 /* clk_disable_unprepare helps cases using clk_disable in non-atomic context. */
1112  * clk_drop_range - Reset any range set on that clock
1115  * Returns success (0) or negative errno.
1123  * clk_get_optional - lookup and obtain a reference to an optional clock
1129  * this case, instead of returning -ENOENT, the function returns NULL.
1135 	if (clk == ERR_PTR(-ENOENT))  in clk_get_optional()
1148 	return ERR_PTR(-ENOENT);  in of_clk_get()
1153 	return ERR_PTR(-ENOENT);  in of_clk_get_by_name()
1157 	return ERR_PTR(-ENOENT);  in of_clk_get_from_provider()