xref: /linux-6.15/include/linux/regmap.h (revision 8cd3c556)
1 #ifndef __LINUX_REGMAP_H
2 #define __LINUX_REGMAP_H
3 
4 /*
5  * Register map access API
6  *
7  * Copyright 2011 Wolfson Microelectronics plc
8  *
9  * Author: Mark Brown <[email protected]>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  */
15 
16 #include <linux/list.h>
17 #include <linux/rbtree.h>
18 
19 struct module;
20 struct device;
21 struct i2c_client;
22 struct irq_domain;
23 struct spi_device;
24 struct regmap;
25 struct regmap_range_cfg;
26 struct regmap_field;
27 
28 /* An enum of all the supported cache types */
29 enum regcache_type {
30 	REGCACHE_NONE,
31 	REGCACHE_RBTREE,
32 	REGCACHE_COMPRESSED,
33 	REGCACHE_FLAT,
34 };
35 
36 /**
37  * Default value for a register.  We use an array of structs rather
38  * than a simple array as many modern devices have very sparse
39  * register maps.
40  *
41  * @reg: Register address.
42  * @def: Register default value.
43  */
44 struct reg_default {
45 	unsigned int reg;
46 	unsigned int def;
47 };
48 
49 #ifdef CONFIG_REGMAP
50 
51 enum regmap_endian {
52 	/* Unspecified -> 0 -> Backwards compatible default */
53 	REGMAP_ENDIAN_DEFAULT = 0,
54 	REGMAP_ENDIAN_BIG,
55 	REGMAP_ENDIAN_LITTLE,
56 	REGMAP_ENDIAN_NATIVE,
57 };
58 
59 /**
60  * A register range, used for access related checks
61  * (readable/writeable/volatile/precious checks)
62  *
63  * @range_min: address of first register
64  * @range_max: address of last register
65  */
66 struct regmap_range {
67 	unsigned int range_min;
68 	unsigned int range_max;
69 };
70 
71 /*
72  * A table of ranges including some yes ranges and some no ranges.
73  * If a register belongs to a no_range, the corresponding check function
74  * will return false. If a register belongs to a yes range, the corresponding
75  * check function will return true. "no_ranges" are searched first.
76  *
77  * @yes_ranges : pointer to an array of regmap ranges used as "yes ranges"
78  * @n_yes_ranges: size of the above array
79  * @no_ranges: pointer to an array of regmap ranges used as "no ranges"
80  * @n_no_ranges: size of the above array
81  */
82 struct regmap_access_table {
83 	const struct regmap_range *yes_ranges;
84 	unsigned int n_yes_ranges;
85 	const struct regmap_range *no_ranges;
86 	unsigned int n_no_ranges;
87 };
88 
89 typedef void (*regmap_lock)(void *);
90 typedef void (*regmap_unlock)(void *);
91 
92 /**
93  * Configuration for the register map of a device.
94  *
95  * @name: Optional name of the regmap. Useful when a device has multiple
96  *        register regions.
97  *
98  * @reg_bits: Number of bits in a register address, mandatory.
99  * @reg_stride: The register address stride. Valid register addresses are a
100  *              multiple of this value. If set to 0, a value of 1 will be
101  *              used.
102  * @pad_bits: Number of bits of padding between register and value.
103  * @val_bits: Number of bits in a register value, mandatory.
104  *
105  * @writeable_reg: Optional callback returning true if the register
106  *		   can be written to. If this field is NULL but wr_table
107  *		   (see below) is not, the check is performed on such table
108  *                 (a register is writeable if it belongs to one of the ranges
109  *                  specified by wr_table).
110  * @readable_reg: Optional callback returning true if the register
111  *		  can be read from. If this field is NULL but rd_table
112  *		   (see below) is not, the check is performed on such table
113  *                 (a register is readable if it belongs to one of the ranges
114  *                  specified by rd_table).
115  * @volatile_reg: Optional callback returning true if the register
116  *		  value can't be cached. If this field is NULL but
117  *		  volatile_table (see below) is not, the check is performed on
118  *                such table (a register is volatile if it belongs to one of
119  *                the ranges specified by volatile_table).
120  * @precious_reg: Optional callback returning true if the rgister
121  *		  should not be read outside of a call from the driver
122  *		  (eg, a clear on read interrupt status register). If this
123  *                field is NULL but precious_table (see below) is not, the
124  *                check is performed on such table (a register is precious if
125  *                it belongs to one of the ranges specified by precious_table).
126  * @lock:	  Optional lock callback (overrides regmap's default lock
127  *		  function, based on spinlock or mutex).
128  * @unlock:	  As above for unlocking.
129  * @lock_arg:	  this field is passed as the only argument of lock/unlock
130  *		  functions (ignored in case regular lock/unlock functions
131  *		  are not overridden).
132  * @reg_read:	  Optional callback that if filled will be used to perform
133  *           	  all the reads from the registers. Should only be provided for
134  *		  devices whos read operation cannot be represented as a simple read
135  *		  operation on a bus such as SPI, I2C, etc. Most of the devices do
136  * 		  not need this.
137  * @reg_write:	  Same as above for writing.
138  * @fast_io:	  Register IO is fast. Use a spinlock instead of a mutex
139  *	     	  to perform locking. This field is ignored if custom lock/unlock
140  *	     	  functions are used (see fields lock/unlock of struct regmap_config).
141  *		  This field is a duplicate of a similar file in
142  *		  'struct regmap_bus' and serves exact same purpose.
143  *		   Use it only for "no-bus" cases.
144  * @max_register: Optional, specifies the maximum valid register index.
145  * @wr_table:     Optional, points to a struct regmap_access_table specifying
146  *                valid ranges for write access.
147  * @rd_table:     As above, for read access.
148  * @volatile_table: As above, for volatile registers.
149  * @precious_table: As above, for precious registers.
150  * @reg_defaults: Power on reset values for registers (for use with
151  *                register cache support).
152  * @num_reg_defaults: Number of elements in reg_defaults.
153  *
154  * @read_flag_mask: Mask to be set in the top byte of the register when doing
155  *                  a read.
156  * @write_flag_mask: Mask to be set in the top byte of the register when doing
157  *                   a write. If both read_flag_mask and write_flag_mask are
158  *                   empty the regmap_bus default masks are used.
159  * @use_single_rw: If set, converts the bulk read and write operations into
160  *		    a series of single read and write operations. This is useful
161  *		    for device that does not support bulk read and write.
162  *
163  * @cache_type: The actual cache type.
164  * @reg_defaults_raw: Power on reset values for registers (for use with
165  *                    register cache support).
166  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
167  * @reg_format_endian: Endianness for formatted register addresses. If this is
168  *                     DEFAULT, the @reg_format_endian_default value from the
169  *                     regmap bus is used.
170  * @val_format_endian: Endianness for formatted register values. If this is
171  *                     DEFAULT, the @reg_format_endian_default value from the
172  *                     regmap bus is used.
173  *
174  * @ranges: Array of configuration entries for virtual address ranges.
175  * @num_ranges: Number of range configuration entries.
176  */
177 struct regmap_config {
178 	const char *name;
179 
180 	int reg_bits;
181 	int reg_stride;
182 	int pad_bits;
183 	int val_bits;
184 
185 	bool (*writeable_reg)(struct device *dev, unsigned int reg);
186 	bool (*readable_reg)(struct device *dev, unsigned int reg);
187 	bool (*volatile_reg)(struct device *dev, unsigned int reg);
188 	bool (*precious_reg)(struct device *dev, unsigned int reg);
189 	regmap_lock lock;
190 	regmap_unlock unlock;
191 	void *lock_arg;
192 
193 	int (*reg_read)(void *context, unsigned int reg, unsigned int *val);
194 	int (*reg_write)(void *context, unsigned int reg, unsigned int val);
195 
196 	bool fast_io;
197 
198 	unsigned int max_register;
199 	const struct regmap_access_table *wr_table;
200 	const struct regmap_access_table *rd_table;
201 	const struct regmap_access_table *volatile_table;
202 	const struct regmap_access_table *precious_table;
203 	const struct reg_default *reg_defaults;
204 	unsigned int num_reg_defaults;
205 	enum regcache_type cache_type;
206 	const void *reg_defaults_raw;
207 	unsigned int num_reg_defaults_raw;
208 
209 	u8 read_flag_mask;
210 	u8 write_flag_mask;
211 
212 	bool use_single_rw;
213 
214 	enum regmap_endian reg_format_endian;
215 	enum regmap_endian val_format_endian;
216 
217 	const struct regmap_range_cfg *ranges;
218 	unsigned int num_ranges;
219 };
220 
221 /**
222  * Configuration for indirectly accessed or paged registers.
223  * Registers, mapped to this virtual range, are accessed in two steps:
224  *     1. page selector register update;
225  *     2. access through data window registers.
226  *
227  * @name: Descriptive name for diagnostics
228  *
229  * @range_min: Address of the lowest register address in virtual range.
230  * @range_max: Address of the highest register in virtual range.
231  *
232  * @page_sel_reg: Register with selector field.
233  * @page_sel_mask: Bit shift for selector value.
234  * @page_sel_shift: Bit mask for selector value.
235  *
236  * @window_start: Address of first (lowest) register in data window.
237  * @window_len: Number of registers in data window.
238  */
239 struct regmap_range_cfg {
240 	const char *name;
241 
242 	/* Registers of virtual address range */
243 	unsigned int range_min;
244 	unsigned int range_max;
245 
246 	/* Page selector for indirect addressing */
247 	unsigned int selector_reg;
248 	unsigned int selector_mask;
249 	int selector_shift;
250 
251 	/* Data window (per each page) */
252 	unsigned int window_start;
253 	unsigned int window_len;
254 };
255 
256 struct regmap_async;
257 
258 typedef int (*regmap_hw_write)(void *context, const void *data,
259 			       size_t count);
260 typedef int (*regmap_hw_gather_write)(void *context,
261 				      const void *reg, size_t reg_len,
262 				      const void *val, size_t val_len);
263 typedef int (*regmap_hw_async_write)(void *context,
264 				     const void *reg, size_t reg_len,
265 				     const void *val, size_t val_len,
266 				     struct regmap_async *async);
267 typedef int (*regmap_hw_read)(void *context,
268 			      const void *reg_buf, size_t reg_size,
269 			      void *val_buf, size_t val_size);
270 typedef struct regmap_async *(*regmap_hw_async_alloc)(void);
271 typedef void (*regmap_hw_free_context)(void *context);
272 
273 /**
274  * Description of a hardware bus for the register map infrastructure.
275  *
276  * @fast_io: Register IO is fast. Use a spinlock instead of a mutex
277  *	     to perform locking. This field is ignored if custom lock/unlock
278  *	     functions are used (see fields lock/unlock of
279  *	     struct regmap_config).
280  * @write: Write operation.
281  * @gather_write: Write operation with split register/value, return -ENOTSUPP
282  *                if not implemented  on a given device.
283  * @async_write: Write operation which completes asynchronously, optional and
284  *               must serialise with respect to non-async I/O.
285  * @read: Read operation.  Data is returned in the buffer used to transmit
286  *         data.
287  * @async_alloc: Allocate a regmap_async() structure.
288  * @read_flag_mask: Mask to be set in the top byte of the register when doing
289  *                  a read.
290  * @reg_format_endian_default: Default endianness for formatted register
291  *     addresses. Used when the regmap_config specifies DEFAULT. If this is
292  *     DEFAULT, BIG is assumed.
293  * @val_format_endian_default: Default endianness for formatted register
294  *     values. Used when the regmap_config specifies DEFAULT. If this is
295  *     DEFAULT, BIG is assumed.
296  * @async_size: Size of struct used for async work.
297  */
298 struct regmap_bus {
299 	bool fast_io;
300 	regmap_hw_write write;
301 	regmap_hw_gather_write gather_write;
302 	regmap_hw_async_write async_write;
303 	regmap_hw_read read;
304 	regmap_hw_free_context free_context;
305 	regmap_hw_async_alloc async_alloc;
306 	u8 read_flag_mask;
307 	enum regmap_endian reg_format_endian_default;
308 	enum regmap_endian val_format_endian_default;
309 };
310 
311 struct regmap *regmap_init(struct device *dev,
312 			   const struct regmap_bus *bus,
313 			   void *bus_context,
314 			   const struct regmap_config *config);
315 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
316 			       const struct regmap_config *config);
317 struct regmap *regmap_init_spi(struct spi_device *dev,
318 			       const struct regmap_config *config);
319 struct regmap *regmap_init_mmio_clk(struct device *dev, const char *clk_id,
320 				    void __iomem *regs,
321 				    const struct regmap_config *config);
322 
323 struct regmap *devm_regmap_init(struct device *dev,
324 				const struct regmap_bus *bus,
325 				void *bus_context,
326 				const struct regmap_config *config);
327 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
328 				    const struct regmap_config *config);
329 struct regmap *devm_regmap_init_spi(struct spi_device *dev,
330 				    const struct regmap_config *config);
331 struct regmap *devm_regmap_init_mmio_clk(struct device *dev, const char *clk_id,
332 					 void __iomem *regs,
333 					 const struct regmap_config *config);
334 
335 /**
336  * regmap_init_mmio(): Initialise register map
337  *
338  * @dev: Device that will be interacted with
339  * @regs: Pointer to memory-mapped IO region
340  * @config: Configuration for register map
341  *
342  * The return value will be an ERR_PTR() on error or a valid pointer to
343  * a struct regmap.
344  */
345 static inline struct regmap *regmap_init_mmio(struct device *dev,
346 					void __iomem *regs,
347 					const struct regmap_config *config)
348 {
349 	return regmap_init_mmio_clk(dev, NULL, regs, config);
350 }
351 
352 /**
353  * devm_regmap_init_mmio(): Initialise managed register map
354  *
355  * @dev: Device that will be interacted with
356  * @regs: Pointer to memory-mapped IO region
357  * @config: Configuration for register map
358  *
359  * The return value will be an ERR_PTR() on error or a valid pointer
360  * to a struct regmap.  The regmap will be automatically freed by the
361  * device management code.
362  */
363 static inline struct regmap *devm_regmap_init_mmio(struct device *dev,
364 					void __iomem *regs,
365 					const struct regmap_config *config)
366 {
367 	return devm_regmap_init_mmio_clk(dev, NULL, regs, config);
368 }
369 
370 void regmap_exit(struct regmap *map);
371 int regmap_reinit_cache(struct regmap *map,
372 			const struct regmap_config *config);
373 struct regmap *dev_get_regmap(struct device *dev, const char *name);
374 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
375 int regmap_raw_write(struct regmap *map, unsigned int reg,
376 		     const void *val, size_t val_len);
377 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
378 			size_t val_count);
379 int regmap_raw_write_async(struct regmap *map, unsigned int reg,
380 			   const void *val, size_t val_len);
381 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
382 int regmap_raw_read(struct regmap *map, unsigned int reg,
383 		    void *val, size_t val_len);
384 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
385 		     size_t val_count);
386 int regmap_update_bits(struct regmap *map, unsigned int reg,
387 		       unsigned int mask, unsigned int val);
388 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
389 			     unsigned int mask, unsigned int val,
390 			     bool *change);
391 int regmap_get_val_bytes(struct regmap *map);
392 int regmap_async_complete(struct regmap *map);
393 bool regmap_can_raw_write(struct regmap *map);
394 
395 int regcache_sync(struct regmap *map);
396 int regcache_sync_region(struct regmap *map, unsigned int min,
397 			 unsigned int max);
398 int regcache_drop_region(struct regmap *map, unsigned int min,
399 			 unsigned int max);
400 void regcache_cache_only(struct regmap *map, bool enable);
401 void regcache_cache_bypass(struct regmap *map, bool enable);
402 void regcache_mark_dirty(struct regmap *map);
403 
404 bool regmap_check_range_table(struct regmap *map, unsigned int reg,
405 			      const struct regmap_access_table *table);
406 
407 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
408 			  int num_regs);
409 
410 static inline bool regmap_reg_in_range(unsigned int reg,
411 				       const struct regmap_range *range)
412 {
413 	return reg >= range->range_min && reg <= range->range_max;
414 }
415 
416 bool regmap_reg_in_ranges(unsigned int reg,
417 			  const struct regmap_range *ranges,
418 			  unsigned int nranges);
419 
420 /**
421  * Description of an register field
422  *
423  * @reg: Offset of the register within the regmap bank
424  * @lsb: lsb of the register field.
425  * @reg: msb of the register field.
426  */
427 struct reg_field {
428 	unsigned int reg;
429 	unsigned int lsb;
430 	unsigned int msb;
431 };
432 
433 #define REG_FIELD(_reg, _lsb, _msb) {		\
434 				.reg = _reg,	\
435 				.lsb = _lsb,	\
436 				.msb = _msb,	\
437 				}
438 
439 struct regmap_field *regmap_field_alloc(struct regmap *regmap,
440 		struct reg_field reg_field);
441 void regmap_field_free(struct regmap_field *field);
442 
443 struct regmap_field *devm_regmap_field_alloc(struct device *dev,
444 		struct regmap *regmap, struct reg_field reg_field);
445 void devm_regmap_field_free(struct device *dev,	struct regmap_field *field);
446 
447 int regmap_field_read(struct regmap_field *field, unsigned int *val);
448 int regmap_field_write(struct regmap_field *field, unsigned int val);
449 
450 /**
451  * Description of an IRQ for the generic regmap irq_chip.
452  *
453  * @reg_offset: Offset of the status/mask register within the bank
454  * @mask:       Mask used to flag/control the register.
455  */
456 struct regmap_irq {
457 	unsigned int reg_offset;
458 	unsigned int mask;
459 };
460 
461 /**
462  * Description of a generic regmap irq_chip.  This is not intended to
463  * handle every possible interrupt controller, but it should handle a
464  * substantial proportion of those that are found in the wild.
465  *
466  * @name:        Descriptive name for IRQ controller.
467  *
468  * @status_base: Base status register address.
469  * @mask_base:   Base mask register address.
470  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
471  * @wake_base:   Base address for wake enables.  If zero unsupported.
472  * @irq_reg_stride:  Stride to use for chips where registers are not contiguous.
473  * @runtime_pm:  Hold a runtime PM lock on the device when accessing it.
474  *
475  * @num_regs:    Number of registers in each control bank.
476  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
477  *               assigned based on the index in the array of the interrupt.
478  * @num_irqs:    Number of descriptors.
479  */
480 struct regmap_irq_chip {
481 	const char *name;
482 
483 	unsigned int status_base;
484 	unsigned int mask_base;
485 	unsigned int ack_base;
486 	unsigned int wake_base;
487 	unsigned int irq_reg_stride;
488 	unsigned int mask_invert;
489 	unsigned int wake_invert;
490 	bool runtime_pm;
491 
492 	int num_regs;
493 
494 	const struct regmap_irq *irqs;
495 	int num_irqs;
496 };
497 
498 struct regmap_irq_chip_data;
499 
500 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
501 			int irq_base, const struct regmap_irq_chip *chip,
502 			struct regmap_irq_chip_data **data);
503 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
504 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
505 int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq);
506 struct irq_domain *regmap_irq_get_domain(struct regmap_irq_chip_data *data);
507 
508 #else
509 
510 /*
511  * These stubs should only ever be called by generic code which has
512  * regmap based facilities, if they ever get called at runtime
513  * something is going wrong and something probably needs to select
514  * REGMAP.
515  */
516 
517 static inline int regmap_write(struct regmap *map, unsigned int reg,
518 			       unsigned int val)
519 {
520 	WARN_ONCE(1, "regmap API is disabled");
521 	return -EINVAL;
522 }
523 
524 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
525 				   const void *val, size_t val_len)
526 {
527 	WARN_ONCE(1, "regmap API is disabled");
528 	return -EINVAL;
529 }
530 
531 static inline int regmap_raw_write_async(struct regmap *map, unsigned int reg,
532 					 const void *val, size_t val_len)
533 {
534 	WARN_ONCE(1, "regmap API is disabled");
535 	return -EINVAL;
536 }
537 
538 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
539 				    const void *val, size_t val_count)
540 {
541 	WARN_ONCE(1, "regmap API is disabled");
542 	return -EINVAL;
543 }
544 
545 static inline int regmap_read(struct regmap *map, unsigned int reg,
546 			      unsigned int *val)
547 {
548 	WARN_ONCE(1, "regmap API is disabled");
549 	return -EINVAL;
550 }
551 
552 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
553 				  void *val, size_t val_len)
554 {
555 	WARN_ONCE(1, "regmap API is disabled");
556 	return -EINVAL;
557 }
558 
559 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
560 				   void *val, size_t val_count)
561 {
562 	WARN_ONCE(1, "regmap API is disabled");
563 	return -EINVAL;
564 }
565 
566 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
567 				     unsigned int mask, unsigned int val)
568 {
569 	WARN_ONCE(1, "regmap API is disabled");
570 	return -EINVAL;
571 }
572 
573 static inline int regmap_update_bits_check(struct regmap *map,
574 					   unsigned int reg,
575 					   unsigned int mask, unsigned int val,
576 					   bool *change)
577 {
578 	WARN_ONCE(1, "regmap API is disabled");
579 	return -EINVAL;
580 }
581 
582 static inline int regmap_get_val_bytes(struct regmap *map)
583 {
584 	WARN_ONCE(1, "regmap API is disabled");
585 	return -EINVAL;
586 }
587 
588 static inline int regcache_sync(struct regmap *map)
589 {
590 	WARN_ONCE(1, "regmap API is disabled");
591 	return -EINVAL;
592 }
593 
594 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
595 				       unsigned int max)
596 {
597 	WARN_ONCE(1, "regmap API is disabled");
598 	return -EINVAL;
599 }
600 
601 static inline int regcache_drop_region(struct regmap *map, unsigned int min,
602 				       unsigned int max)
603 {
604 	WARN_ONCE(1, "regmap API is disabled");
605 	return -EINVAL;
606 }
607 
608 static inline void regcache_cache_only(struct regmap *map, bool enable)
609 {
610 	WARN_ONCE(1, "regmap API is disabled");
611 }
612 
613 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
614 {
615 	WARN_ONCE(1, "regmap API is disabled");
616 }
617 
618 static inline void regcache_mark_dirty(struct regmap *map)
619 {
620 	WARN_ONCE(1, "regmap API is disabled");
621 }
622 
623 static inline void regmap_async_complete(struct regmap *map)
624 {
625 	WARN_ONCE(1, "regmap API is disabled");
626 }
627 
628 static inline int regmap_register_patch(struct regmap *map,
629 					const struct reg_default *regs,
630 					int num_regs)
631 {
632 	WARN_ONCE(1, "regmap API is disabled");
633 	return -EINVAL;
634 }
635 
636 static inline struct regmap *dev_get_regmap(struct device *dev,
637 					    const char *name)
638 {
639 	return NULL;
640 }
641 
642 #endif
643 
644 #endif
645