clk-provider.h revision 9824cf73c3a5e677bee6fcba43c4807e01ff1b4a
1/*
2 *  linux/include/linux/clk-provider.h
3 *
4 *  Copyright (c) 2010-2011 Jeremy Kerr <jeremy.kerr@canonical.com>
5 *  Copyright (C) 2011-2012 Linaro Ltd <mturquette@linaro.org>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#ifndef __LINUX_CLK_PROVIDER_H
12#define __LINUX_CLK_PROVIDER_H
13
14#include <linux/clk.h>
15#include <linux/io.h>
16#include <linux/of.h>
17
18#ifdef CONFIG_COMMON_CLK
19
20/*
21 * flags used across common struct clk.  these flags should only affect the
22 * top-level framework.  custom flags for dealing with hardware specifics
23 * belong in struct clk_foo
24 */
25#define CLK_SET_RATE_GATE	BIT(0) /* must be gated across rate change */
26#define CLK_SET_PARENT_GATE	BIT(1) /* must be gated across re-parent */
27#define CLK_SET_RATE_PARENT	BIT(2) /* propagate rate change up one level */
28#define CLK_IGNORE_UNUSED	BIT(3) /* do not gate even if unused */
29#define CLK_IS_ROOT		BIT(4) /* root clk, has no parent */
30#define CLK_IS_BASIC		BIT(5) /* Basic clk, can't do a to_clk_foo() */
31#define CLK_GET_RATE_NOCACHE	BIT(6) /* do not use the cached clk rate */
32#define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */
33#define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */
34
35struct clk_hw;
36struct dentry;
37
38/**
39 * struct clk_ops -  Callback operations for hardware clocks; these are to
40 * be provided by the clock implementation, and will be called by drivers
41 * through the clk_* api.
42 *
43 * @prepare:	Prepare the clock for enabling. This must not return until
44 *		the clock is fully prepared, and it's safe to call clk_enable.
45 *		This callback is intended to allow clock implementations to
46 *		do any initialisation that may sleep. Called with
47 *		prepare_lock held.
48 *
49 * @unprepare:	Release the clock from its prepared state. This will typically
50 *		undo any work done in the @prepare callback. Called with
51 *		prepare_lock held.
52 *
53 * @is_prepared: Queries the hardware to determine if the clock is prepared.
54 *		This function is allowed to sleep. Optional, if this op is not
55 *		set then the prepare count will be used.
56 *
57 * @unprepare_unused: Unprepare the clock atomically.  Only called from
58 *		clk_disable_unused for prepare clocks with special needs.
59 *		Called with prepare mutex held. This function may sleep.
60 *
61 * @enable:	Enable the clock atomically. This must not return until the
62 *		clock is generating a valid clock signal, usable by consumer
63 *		devices. Called with enable_lock held. This function must not
64 *		sleep.
65 *
66 * @disable:	Disable the clock atomically. Called with enable_lock held.
67 *		This function must not sleep.
68 *
69 * @is_enabled:	Queries the hardware to determine if the clock is enabled.
70 *		This function must not sleep. Optional, if this op is not
71 *		set then the enable count will be used.
72 *
73 * @disable_unused: Disable the clock atomically.  Only called from
74 *		clk_disable_unused for gate clocks with special needs.
75 *		Called with enable_lock held.  This function must not
76 *		sleep.
77 *
78 * @recalc_rate	Recalculate the rate of this clock, by querying hardware. The
79 *		parent rate is an input parameter.  It is up to the caller to
80 *		ensure that the prepare_mutex is held across this call.
81 *		Returns the calculated rate.  Optional, but recommended - if
82 *		this op is not set then clock rate will be initialized to 0.
83 *
84 * @round_rate:	Given a target rate as input, returns the closest rate actually
85 *		supported by the clock. The parent rate is an input/output
86 *		parameter.
87 *
88 * @determine_rate: Given a target rate as input, returns the closest rate
89 *		actually supported by the clock, and optionally the parent clock
90 *		that should be used to provide the clock rate.
91 *
92 * @set_parent:	Change the input source of this clock; for clocks with multiple
93 *		possible parents specify a new parent by passing in the index
94 *		as a u8 corresponding to the parent in either the .parent_names
95 *		or .parents arrays.  This function in affect translates an
96 *		array index into the value programmed into the hardware.
97 *		Returns 0 on success, -EERROR otherwise.
98 *
99 * @get_parent:	Queries the hardware to determine the parent of a clock.  The
100 *		return value is a u8 which specifies the index corresponding to
101 *		the parent clock.  This index can be applied to either the
102 *		.parent_names or .parents arrays.  In short, this function
103 *		translates the parent value read from hardware into an array
104 *		index.  Currently only called when the clock is initialized by
105 *		__clk_init.  This callback is mandatory for clocks with
106 *		multiple parents.  It is optional (and unnecessary) for clocks
107 *		with 0 or 1 parents.
108 *
109 * @set_rate:	Change the rate of this clock. The requested rate is specified
110 *		by the second argument, which should typically be the return
111 *		of .round_rate call.  The third argument gives the parent rate
112 *		which is likely helpful for most .set_rate implementation.
113 *		Returns 0 on success, -EERROR otherwise.
114 *
115 * @set_rate_and_parent: Change the rate and the parent of this clock. The
116 *		requested rate is specified by the second argument, which
117 *		should typically be the return of .round_rate call.  The
118 *		third argument gives the parent rate which is likely helpful
119 *		for most .set_rate_and_parent implementation. The fourth
120 *		argument gives the parent index. This callback is optional (and
121 *		unnecessary) for clocks with 0 or 1 parents as well as
122 *		for clocks that can tolerate switching the rate and the parent
123 *		separately via calls to .set_parent and .set_rate.
124 *		Returns 0 on success, -EERROR otherwise.
125 *
126 * @recalc_accuracy: Recalculate the accuracy of this clock. The clock accuracy
127 *		is expressed in ppb (parts per billion). The parent accuracy is
128 *		an input parameter.
129 *		Returns the calculated accuracy.  Optional - if	this op is not
130 *		set then clock accuracy will be initialized to parent accuracy
131 *		or 0 (perfect clock) if clock has no parent.
132 *
133 * @get_phase:	Queries the hardware to get the current phase of a clock.
134 *		Returned values are 0-359 degrees on success, negative
135 *		error codes on failure.
136 *
137 * @set_phase:	Shift the phase this clock signal in degrees specified
138 *		by the second argument. Valid values for degrees are
139 *		0-359. Return 0 on success, otherwise -EERROR.
140 *
141 * @init:	Perform platform-specific initialization magic.
142 *		This is not not used by any of the basic clock types.
143 *		Please consider other ways of solving initialization problems
144 *		before using this callback, as its use is discouraged.
145 *
146 * @debug_init:	Set up type-specific debugfs entries for this clock.  This
147 *		is called once, after the debugfs directory entry for this
148 *		clock has been created.  The dentry pointer representing that
149 *		directory is provided as an argument.  Called with
150 *		prepare_lock held.  Returns 0 on success, -EERROR otherwise.
151 *
152 *
153 * The clk_enable/clk_disable and clk_prepare/clk_unprepare pairs allow
154 * implementations to split any work between atomic (enable) and sleepable
155 * (prepare) contexts.  If enabling a clock requires code that might sleep,
156 * this must be done in clk_prepare.  Clock enable code that will never be
157 * called in a sleepable context may be implemented in clk_enable.
158 *
159 * Typically, drivers will call clk_prepare when a clock may be needed later
160 * (eg. when a device is opened), and clk_enable when the clock is actually
161 * required (eg. from an interrupt). Note that clk_prepare MUST have been
162 * called before clk_enable.
163 */
164struct clk_ops {
165	int		(*prepare)(struct clk_hw *hw);
166	void		(*unprepare)(struct clk_hw *hw);
167	int		(*is_prepared)(struct clk_hw *hw);
168	void		(*unprepare_unused)(struct clk_hw *hw);
169	int		(*enable)(struct clk_hw *hw);
170	void		(*disable)(struct clk_hw *hw);
171	int		(*is_enabled)(struct clk_hw *hw);
172	void		(*disable_unused)(struct clk_hw *hw);
173	unsigned long	(*recalc_rate)(struct clk_hw *hw,
174					unsigned long parent_rate);
175	long		(*round_rate)(struct clk_hw *hw, unsigned long rate,
176					unsigned long *parent_rate);
177	long		(*determine_rate)(struct clk_hw *hw, unsigned long rate,
178					unsigned long *best_parent_rate,
179					struct clk **best_parent_clk);
180	int		(*set_parent)(struct clk_hw *hw, u8 index);
181	u8		(*get_parent)(struct clk_hw *hw);
182	int		(*set_rate)(struct clk_hw *hw, unsigned long rate,
183				    unsigned long parent_rate);
184	int		(*set_rate_and_parent)(struct clk_hw *hw,
185				    unsigned long rate,
186				    unsigned long parent_rate, u8 index);
187	unsigned long	(*recalc_accuracy)(struct clk_hw *hw,
188					   unsigned long parent_accuracy);
189	int		(*get_phase)(struct clk_hw *hw);
190	int		(*set_phase)(struct clk_hw *hw, int degrees);
191	void		(*init)(struct clk_hw *hw);
192	int		(*debug_init)(struct clk_hw *hw, struct dentry *dentry);
193};
194
195/**
196 * struct clk_init_data - holds init data that's common to all clocks and is
197 * shared between the clock provider and the common clock framework.
198 *
199 * @name: clock name
200 * @ops: operations this clock supports
201 * @parent_names: array of string names for all possible parents
202 * @num_parents: number of possible parents
203 * @flags: framework-level hints and quirks
204 */
205struct clk_init_data {
206	const char		*name;
207	const struct clk_ops	*ops;
208	const char		**parent_names;
209	u8			num_parents;
210	unsigned long		flags;
211};
212
213/**
214 * struct clk_hw - handle for traversing from a struct clk to its corresponding
215 * hardware-specific structure.  struct clk_hw should be declared within struct
216 * clk_foo and then referenced by the struct clk instance that uses struct
217 * clk_foo's clk_ops
218 *
219 * @clk: pointer to the struct clk instance that points back to this struct
220 * clk_hw instance
221 *
222 * @init: pointer to struct clk_init_data that contains the init data shared
223 * with the common clock framework.
224 */
225struct clk_hw {
226	struct clk *clk;
227	const struct clk_init_data *init;
228};
229
230/*
231 * DOC: Basic clock implementations common to many platforms
232 *
233 * Each basic clock hardware type is comprised of a structure describing the
234 * clock hardware, implementations of the relevant callbacks in struct clk_ops,
235 * unique flags for that hardware type, a registration function and an
236 * alternative macro for static initialization
237 */
238
239/**
240 * struct clk_fixed_rate - fixed-rate clock
241 * @hw:		handle between common and hardware-specific interfaces
242 * @fixed_rate:	constant frequency of clock
243 */
244struct clk_fixed_rate {
245	struct		clk_hw hw;
246	unsigned long	fixed_rate;
247	unsigned long	fixed_accuracy;
248	u8		flags;
249};
250
251extern const struct clk_ops clk_fixed_rate_ops;
252struct clk *clk_register_fixed_rate(struct device *dev, const char *name,
253		const char *parent_name, unsigned long flags,
254		unsigned long fixed_rate);
255struct clk *clk_register_fixed_rate_with_accuracy(struct device *dev,
256		const char *name, const char *parent_name, unsigned long flags,
257		unsigned long fixed_rate, unsigned long fixed_accuracy);
258
259void of_fixed_clk_setup(struct device_node *np);
260
261/**
262 * struct clk_gate - gating clock
263 *
264 * @hw:		handle between common and hardware-specific interfaces
265 * @reg:	register controlling gate
266 * @bit_idx:	single bit controlling gate
267 * @flags:	hardware-specific flags
268 * @lock:	register lock
269 *
270 * Clock which can gate its output.  Implements .enable & .disable
271 *
272 * Flags:
273 * CLK_GATE_SET_TO_DISABLE - by default this clock sets the bit at bit_idx to
274 *	enable the clock.  Setting this flag does the opposite: setting the bit
275 *	disable the clock and clearing it enables the clock
276 * CLK_GATE_HIWORD_MASK - The gate settings are only in lower 16-bit
277 *	of this register, and mask of gate bits are in higher 16-bit of this
278 *	register.  While setting the gate bits, higher 16-bit should also be
279 *	updated to indicate changing gate bits.
280 */
281struct clk_gate {
282	struct clk_hw hw;
283	void __iomem	*reg;
284	u8		bit_idx;
285	u8		flags;
286	spinlock_t	*lock;
287};
288
289#define CLK_GATE_SET_TO_DISABLE		BIT(0)
290#define CLK_GATE_HIWORD_MASK		BIT(1)
291
292extern const struct clk_ops clk_gate_ops;
293struct clk *clk_register_gate(struct device *dev, const char *name,
294		const char *parent_name, unsigned long flags,
295		void __iomem *reg, u8 bit_idx,
296		u8 clk_gate_flags, spinlock_t *lock);
297
298struct clk_div_table {
299	unsigned int	val;
300	unsigned int	div;
301};
302
303/**
304 * struct clk_divider - adjustable divider clock
305 *
306 * @hw:		handle between common and hardware-specific interfaces
307 * @reg:	register containing the divider
308 * @shift:	shift to the divider bit field
309 * @width:	width of the divider bit field
310 * @table:	array of value/divider pairs, last entry should have div = 0
311 * @lock:	register lock
312 *
313 * Clock with an adjustable divider affecting its output frequency.  Implements
314 * .recalc_rate, .set_rate and .round_rate
315 *
316 * Flags:
317 * CLK_DIVIDER_ONE_BASED - by default the divisor is the value read from the
318 *	register plus one.  If CLK_DIVIDER_ONE_BASED is set then the divider is
319 *	the raw value read from the register, with the value of zero considered
320 *	invalid, unless CLK_DIVIDER_ALLOW_ZERO is set.
321 * CLK_DIVIDER_POWER_OF_TWO - clock divisor is 2 raised to the value read from
322 *	the hardware register
323 * CLK_DIVIDER_ALLOW_ZERO - Allow zero divisors.  For dividers which have
324 *	CLK_DIVIDER_ONE_BASED set, it is possible to end up with a zero divisor.
325 *	Some hardware implementations gracefully handle this case and allow a
326 *	zero divisor by not modifying their input clock
327 *	(divide by one / bypass).
328 * CLK_DIVIDER_HIWORD_MASK - The divider settings are only in lower 16-bit
329 *	of this register, and mask of divider bits are in higher 16-bit of this
330 *	register.  While setting the divider bits, higher 16-bit should also be
331 *	updated to indicate changing divider bits.
332 * CLK_DIVIDER_ROUND_CLOSEST - Makes the best calculated divider to be rounded
333 *	to the closest integer instead of the up one.
334 * CLK_DIVIDER_READ_ONLY - The divider settings are preconfigured and should
335 *	not be changed by the clock framework.
336 */
337struct clk_divider {
338	struct clk_hw	hw;
339	void __iomem	*reg;
340	u8		shift;
341	u8		width;
342	u8		flags;
343	const struct clk_div_table	*table;
344	spinlock_t	*lock;
345};
346
347#define CLK_DIVIDER_ONE_BASED		BIT(0)
348#define CLK_DIVIDER_POWER_OF_TWO	BIT(1)
349#define CLK_DIVIDER_ALLOW_ZERO		BIT(2)
350#define CLK_DIVIDER_HIWORD_MASK		BIT(3)
351#define CLK_DIVIDER_ROUND_CLOSEST	BIT(4)
352#define CLK_DIVIDER_READ_ONLY		BIT(5)
353
354extern const struct clk_ops clk_divider_ops;
355extern const struct clk_ops clk_divider_ro_ops;
356struct clk *clk_register_divider(struct device *dev, const char *name,
357		const char *parent_name, unsigned long flags,
358		void __iomem *reg, u8 shift, u8 width,
359		u8 clk_divider_flags, spinlock_t *lock);
360struct clk *clk_register_divider_table(struct device *dev, const char *name,
361		const char *parent_name, unsigned long flags,
362		void __iomem *reg, u8 shift, u8 width,
363		u8 clk_divider_flags, const struct clk_div_table *table,
364		spinlock_t *lock);
365
366/**
367 * struct clk_mux - multiplexer clock
368 *
369 * @hw:		handle between common and hardware-specific interfaces
370 * @reg:	register controlling multiplexer
371 * @shift:	shift to multiplexer bit field
372 * @width:	width of mutliplexer bit field
373 * @flags:	hardware-specific flags
374 * @lock:	register lock
375 *
376 * Clock with multiple selectable parents.  Implements .get_parent, .set_parent
377 * and .recalc_rate
378 *
379 * Flags:
380 * CLK_MUX_INDEX_ONE - register index starts at 1, not 0
381 * CLK_MUX_INDEX_BIT - register index is a single bit (power of two)
382 * CLK_MUX_HIWORD_MASK - The mux settings are only in lower 16-bit of this
383 *	register, and mask of mux bits are in higher 16-bit of this register.
384 *	While setting the mux bits, higher 16-bit should also be updated to
385 *	indicate changing mux bits.
386 */
387struct clk_mux {
388	struct clk_hw	hw;
389	void __iomem	*reg;
390	u32		*table;
391	u32		mask;
392	u8		shift;
393	u8		flags;
394	spinlock_t	*lock;
395};
396
397#define CLK_MUX_INDEX_ONE		BIT(0)
398#define CLK_MUX_INDEX_BIT		BIT(1)
399#define CLK_MUX_HIWORD_MASK		BIT(2)
400#define CLK_MUX_READ_ONLY	BIT(3) /* mux setting cannot be changed */
401
402extern const struct clk_ops clk_mux_ops;
403extern const struct clk_ops clk_mux_ro_ops;
404
405struct clk *clk_register_mux(struct device *dev, const char *name,
406		const char **parent_names, u8 num_parents, unsigned long flags,
407		void __iomem *reg, u8 shift, u8 width,
408		u8 clk_mux_flags, spinlock_t *lock);
409
410struct clk *clk_register_mux_table(struct device *dev, const char *name,
411		const char **parent_names, u8 num_parents, unsigned long flags,
412		void __iomem *reg, u8 shift, u32 mask,
413		u8 clk_mux_flags, u32 *table, spinlock_t *lock);
414
415void of_fixed_factor_clk_setup(struct device_node *node);
416
417/**
418 * struct clk_fixed_factor - fixed multiplier and divider clock
419 *
420 * @hw:		handle between common and hardware-specific interfaces
421 * @mult:	multiplier
422 * @div:	divider
423 *
424 * Clock with a fixed multiplier and divider. The output frequency is the
425 * parent clock rate divided by div and multiplied by mult.
426 * Implements .recalc_rate, .set_rate and .round_rate
427 */
428
429struct clk_fixed_factor {
430	struct clk_hw	hw;
431	unsigned int	mult;
432	unsigned int	div;
433};
434
435extern struct clk_ops clk_fixed_factor_ops;
436struct clk *clk_register_fixed_factor(struct device *dev, const char *name,
437		const char *parent_name, unsigned long flags,
438		unsigned int mult, unsigned int div);
439
440/**
441 * struct clk_fractional_divider - adjustable fractional divider clock
442 *
443 * @hw:		handle between common and hardware-specific interfaces
444 * @reg:	register containing the divider
445 * @mshift:	shift to the numerator bit field
446 * @mwidth:	width of the numerator bit field
447 * @nshift:	shift to the denominator bit field
448 * @nwidth:	width of the denominator bit field
449 * @lock:	register lock
450 *
451 * Clock with adjustable fractional divider affecting its output frequency.
452 */
453
454struct clk_fractional_divider {
455	struct clk_hw	hw;
456	void __iomem	*reg;
457	u8		mshift;
458	u32		mmask;
459	u8		nshift;
460	u32		nmask;
461	u8		flags;
462	spinlock_t	*lock;
463};
464
465extern const struct clk_ops clk_fractional_divider_ops;
466struct clk *clk_register_fractional_divider(struct device *dev,
467		const char *name, const char *parent_name, unsigned long flags,
468		void __iomem *reg, u8 mshift, u8 mwidth, u8 nshift, u8 nwidth,
469		u8 clk_divider_flags, spinlock_t *lock);
470
471/***
472 * struct clk_composite - aggregate clock of mux, divider and gate clocks
473 *
474 * @hw:		handle between common and hardware-specific interfaces
475 * @mux_hw:	handle between composite and hardware-specific mux clock
476 * @rate_hw:	handle between composite and hardware-specific rate clock
477 * @gate_hw:	handle between composite and hardware-specific gate clock
478 * @mux_ops:	clock ops for mux
479 * @rate_ops:	clock ops for rate
480 * @gate_ops:	clock ops for gate
481 */
482struct clk_composite {
483	struct clk_hw	hw;
484	struct clk_ops	ops;
485
486	struct clk_hw	*mux_hw;
487	struct clk_hw	*rate_hw;
488	struct clk_hw	*gate_hw;
489
490	const struct clk_ops	*mux_ops;
491	const struct clk_ops	*rate_ops;
492	const struct clk_ops	*gate_ops;
493};
494
495struct clk *clk_register_composite(struct device *dev, const char *name,
496		const char **parent_names, int num_parents,
497		struct clk_hw *mux_hw, const struct clk_ops *mux_ops,
498		struct clk_hw *rate_hw, const struct clk_ops *rate_ops,
499		struct clk_hw *gate_hw, const struct clk_ops *gate_ops,
500		unsigned long flags);
501
502/**
503 * clk_register - allocate a new clock, register it and return an opaque cookie
504 * @dev: device that is registering this clock
505 * @hw: link to hardware-specific clock data
506 *
507 * clk_register is the primary interface for populating the clock tree with new
508 * clock nodes.  It returns a pointer to the newly allocated struct clk which
509 * cannot be dereferenced by driver code but may be used in conjuction with the
510 * rest of the clock API.  In the event of an error clk_register will return an
511 * error code; drivers must test for an error code after calling clk_register.
512 */
513struct clk *clk_register(struct device *dev, struct clk_hw *hw);
514struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw);
515
516void clk_unregister(struct clk *clk);
517void devm_clk_unregister(struct device *dev, struct clk *clk);
518
519/* helper functions */
520const char *__clk_get_name(struct clk *clk);
521struct clk_hw *__clk_get_hw(struct clk *clk);
522u8 __clk_get_num_parents(struct clk *clk);
523struct clk *__clk_get_parent(struct clk *clk);
524struct clk *clk_get_parent_by_index(struct clk *clk, u8 index);
525unsigned int __clk_get_enable_count(struct clk *clk);
526unsigned int __clk_get_prepare_count(struct clk *clk);
527unsigned long __clk_get_rate(struct clk *clk);
528unsigned long __clk_get_accuracy(struct clk *clk);
529unsigned long __clk_get_flags(struct clk *clk);
530bool __clk_is_prepared(struct clk *clk);
531bool __clk_is_enabled(struct clk *clk);
532struct clk *__clk_lookup(const char *name);
533long __clk_mux_determine_rate(struct clk_hw *hw, unsigned long rate,
534			      unsigned long *best_parent_rate,
535			      struct clk **best_parent_p);
536
537/*
538 * FIXME clock api without lock protection
539 */
540int __clk_prepare(struct clk *clk);
541void __clk_unprepare(struct clk *clk);
542void __clk_reparent(struct clk *clk, struct clk *new_parent);
543unsigned long __clk_round_rate(struct clk *clk, unsigned long rate);
544
545struct of_device_id;
546
547typedef void (*of_clk_init_cb_t)(struct device_node *);
548
549struct clk_onecell_data {
550	struct clk **clks;
551	unsigned int clk_num;
552};
553
554extern struct of_device_id __clk_of_table;
555
556#define CLK_OF_DECLARE(name, compat, fn) OF_DECLARE_1(clk, name, compat, fn)
557
558#ifdef CONFIG_OF
559int of_clk_add_provider(struct device_node *np,
560			struct clk *(*clk_src_get)(struct of_phandle_args *args,
561						   void *data),
562			void *data);
563void of_clk_del_provider(struct device_node *np);
564struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
565				  void *data);
566struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data);
567int of_clk_get_parent_count(struct device_node *np);
568const char *of_clk_get_parent_name(struct device_node *np, int index);
569
570void of_clk_init(const struct of_device_id *matches);
571
572#else /* !CONFIG_OF */
573
574static inline int of_clk_add_provider(struct device_node *np,
575			struct clk *(*clk_src_get)(struct of_phandle_args *args,
576						   void *data),
577			void *data)
578{
579	return 0;
580}
581#define of_clk_del_provider(np) \
582	{ while (0); }
583static inline struct clk *of_clk_src_simple_get(
584	struct of_phandle_args *clkspec, void *data)
585{
586	return ERR_PTR(-ENOENT);
587}
588static inline struct clk *of_clk_src_onecell_get(
589	struct of_phandle_args *clkspec, void *data)
590{
591	return ERR_PTR(-ENOENT);
592}
593static inline const char *of_clk_get_parent_name(struct device_node *np,
594						 int index)
595{
596	return NULL;
597}
598#define of_clk_init(matches) \
599	{ while (0); }
600#endif /* CONFIG_OF */
601
602/*
603 * wrap access to peripherals in accessor routines
604 * for improved portability across platforms
605 */
606
607#if IS_ENABLED(CONFIG_PPC)
608
609static inline u32 clk_readl(u32 __iomem *reg)
610{
611	return ioread32be(reg);
612}
613
614static inline void clk_writel(u32 val, u32 __iomem *reg)
615{
616	iowrite32be(val, reg);
617}
618
619#else	/* platform dependent I/O accessors */
620
621static inline u32 clk_readl(u32 __iomem *reg)
622{
623	return readl(reg);
624}
625
626static inline void clk_writel(u32 val, u32 __iomem *reg)
627{
628	writel(val, reg);
629}
630
631#endif	/* platform dependent I/O accessors */
632
633#ifdef CONFIG_DEBUG_FS
634struct dentry *clk_debugfs_add_file(struct clk *clk, char *name, umode_t mode,
635				void *data, const struct file_operations *fops);
636#endif
637
638#endif /* CONFIG_COMMON_CLK */
639#endif /* CLK_PROVIDER_H */
640