xref: /linux-6.15/include/linux/regmap.h (revision d89dffa9)
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 spi_device;
23 struct regmap;
24 struct regmap_range_cfg;
25 
26 /* An enum of all the supported cache types */
27 enum regcache_type {
28 	REGCACHE_NONE,
29 	REGCACHE_RBTREE,
30 	REGCACHE_COMPRESSED
31 };
32 
33 /**
34  * Default value for a register.  We use an array of structs rather
35  * than a simple array as many modern devices have very sparse
36  * register maps.
37  *
38  * @reg: Register address.
39  * @def: Register default value.
40  */
41 struct reg_default {
42 	unsigned int reg;
43 	unsigned int def;
44 };
45 
46 #ifdef CONFIG_REGMAP
47 
48 enum regmap_endian {
49 	/* Unspecified -> 0 -> Backwards compatible default */
50 	REGMAP_ENDIAN_DEFAULT = 0,
51 	REGMAP_ENDIAN_BIG,
52 	REGMAP_ENDIAN_LITTLE,
53 	REGMAP_ENDIAN_NATIVE,
54 };
55 
56 /**
57  * Configuration for the register map of a device.
58  *
59  * @name: Optional name of the regmap. Useful when a device has multiple
60  *        register regions.
61  *
62  * @reg_bits: Number of bits in a register address, mandatory.
63  * @reg_stride: The register address stride. Valid register addresses are a
64  *              multiple of this value. If set to 0, a value of 1 will be
65  *              used.
66  * @pad_bits: Number of bits of padding between register and value.
67  * @val_bits: Number of bits in a register value, mandatory.
68  *
69  * @writeable_reg: Optional callback returning true if the register
70  *                 can be written to.
71  * @readable_reg: Optional callback returning true if the register
72  *                can be read from.
73  * @volatile_reg: Optional callback returning true if the register
74  *                value can't be cached.
75  * @precious_reg: Optional callback returning true if the rgister
76  *                should not be read outside of a call from the driver
77  *                (eg, a clear on read interrupt status register).
78  *
79  * @max_register: Optional, specifies the maximum valid register index.
80  * @reg_defaults: Power on reset values for registers (for use with
81  *                register cache support).
82  * @num_reg_defaults: Number of elements in reg_defaults.
83  *
84  * @read_flag_mask: Mask to be set in the top byte of the register when doing
85  *                  a read.
86  * @write_flag_mask: Mask to be set in the top byte of the register when doing
87  *                   a write. If both read_flag_mask and write_flag_mask are
88  *                   empty the regmap_bus default masks are used.
89  * @use_single_rw: If set, converts the bulk read and write operations into
90  *		    a series of single read and write operations. This is useful
91  *		    for device that does not support bulk read and write.
92  *
93  * @cache_type: The actual cache type.
94  * @reg_defaults_raw: Power on reset values for registers (for use with
95  *                    register cache support).
96  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
97  * @reg_format_endian: Endianness for formatted register addresses. If this is
98  *                     DEFAULT, the @reg_format_endian_default value from the
99  *                     regmap bus is used.
100  * @val_format_endian: Endianness for formatted register values. If this is
101  *                     DEFAULT, the @reg_format_endian_default value from the
102  *                     regmap bus is used.
103  *
104  * @ranges: Array of configuration entries for virtual address ranges.
105  * @num_ranges: Number of range configuration entries.
106  */
107 struct regmap_config {
108 	const char *name;
109 
110 	int reg_bits;
111 	int reg_stride;
112 	int pad_bits;
113 	int val_bits;
114 
115 	bool (*writeable_reg)(struct device *dev, unsigned int reg);
116 	bool (*readable_reg)(struct device *dev, unsigned int reg);
117 	bool (*volatile_reg)(struct device *dev, unsigned int reg);
118 	bool (*precious_reg)(struct device *dev, unsigned int reg);
119 
120 	unsigned int max_register;
121 	const struct reg_default *reg_defaults;
122 	unsigned int num_reg_defaults;
123 	enum regcache_type cache_type;
124 	const void *reg_defaults_raw;
125 	unsigned int num_reg_defaults_raw;
126 
127 	u8 read_flag_mask;
128 	u8 write_flag_mask;
129 
130 	bool use_single_rw;
131 
132 	enum regmap_endian reg_format_endian;
133 	enum regmap_endian val_format_endian;
134 
135 	const struct regmap_range_cfg *ranges;
136 	unsigned int n_ranges;
137 };
138 
139 /**
140  * Configuration for indirectly accessed or paged registers.
141  * Registers, mapped to this virtual range, are accessed in two steps:
142  *     1. page selector register update;
143  *     2. access through data window registers.
144  *
145  * @range_min: Address of the lowest register address in virtual range.
146  * @range_max: Address of the highest register in virtual range.
147  *
148  * @page_sel_reg: Register with selector field.
149  * @page_sel_mask: Bit shift for selector value.
150  * @page_sel_shift: Bit mask for selector value.
151  *
152  * @window_start: Address of first (lowest) register in data window.
153  * @window_len: Number of registers in data window.
154  */
155 struct regmap_range_cfg {
156 	/* Registers of virtual address range */
157 	unsigned int range_min;
158 	unsigned int range_max;
159 
160 	/* Page selector for indirect addressing */
161 	unsigned int selector_reg;
162 	unsigned int selector_mask;
163 	int selector_shift;
164 
165 	/* Data window (per each page) */
166 	unsigned int window_start;
167 	unsigned int window_len;
168 };
169 
170 typedef int (*regmap_hw_write)(void *context, const void *data,
171 			       size_t count);
172 typedef int (*regmap_hw_gather_write)(void *context,
173 				      const void *reg, size_t reg_len,
174 				      const void *val, size_t val_len);
175 typedef int (*regmap_hw_read)(void *context,
176 			      const void *reg_buf, size_t reg_size,
177 			      void *val_buf, size_t val_size);
178 typedef void (*regmap_hw_free_context)(void *context);
179 
180 /**
181  * Description of a hardware bus for the register map infrastructure.
182  *
183  * @fast_io: Register IO is fast. Use a spinlock instead of a mutex
184  *           to perform locking.
185  * @write: Write operation.
186  * @gather_write: Write operation with split register/value, return -ENOTSUPP
187  *                if not implemented  on a given device.
188  * @read: Read operation.  Data is returned in the buffer used to transmit
189  *         data.
190  * @read_flag_mask: Mask to be set in the top byte of the register when doing
191  *                  a read.
192  * @reg_format_endian_default: Default endianness for formatted register
193  *     addresses. Used when the regmap_config specifies DEFAULT. If this is
194  *     DEFAULT, BIG is assumed.
195  * @val_format_endian_default: Default endianness for formatted register
196  *     values. Used when the regmap_config specifies DEFAULT. If this is
197  *     DEFAULT, BIG is assumed.
198  */
199 struct regmap_bus {
200 	bool fast_io;
201 	regmap_hw_write write;
202 	regmap_hw_gather_write gather_write;
203 	regmap_hw_read read;
204 	regmap_hw_free_context free_context;
205 	u8 read_flag_mask;
206 	enum regmap_endian reg_format_endian_default;
207 	enum regmap_endian val_format_endian_default;
208 };
209 
210 struct regmap *regmap_init(struct device *dev,
211 			   const struct regmap_bus *bus,
212 			   void *bus_context,
213 			   const struct regmap_config *config);
214 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
215 			       const struct regmap_config *config);
216 struct regmap *regmap_init_spi(struct spi_device *dev,
217 			       const struct regmap_config *config);
218 struct regmap *regmap_init_mmio(struct device *dev,
219 				void __iomem *regs,
220 				const struct regmap_config *config);
221 
222 struct regmap *devm_regmap_init(struct device *dev,
223 				const struct regmap_bus *bus,
224 				void *bus_context,
225 				const struct regmap_config *config);
226 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
227 				    const struct regmap_config *config);
228 struct regmap *devm_regmap_init_spi(struct spi_device *dev,
229 				    const struct regmap_config *config);
230 struct regmap *devm_regmap_init_mmio(struct device *dev,
231 				     void __iomem *regs,
232 				     const struct regmap_config *config);
233 
234 void regmap_exit(struct regmap *map);
235 int regmap_reinit_cache(struct regmap *map,
236 			const struct regmap_config *config);
237 struct regmap *dev_get_regmap(struct device *dev, const char *name);
238 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
239 int regmap_raw_write(struct regmap *map, unsigned int reg,
240 		     const void *val, size_t val_len);
241 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
242 			size_t val_count);
243 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
244 int regmap_raw_read(struct regmap *map, unsigned int reg,
245 		    void *val, size_t val_len);
246 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
247 		     size_t val_count);
248 int regmap_update_bits(struct regmap *map, unsigned int reg,
249 		       unsigned int mask, unsigned int val);
250 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
251 			     unsigned int mask, unsigned int val,
252 			     bool *change);
253 int regmap_get_val_bytes(struct regmap *map);
254 
255 int regcache_sync(struct regmap *map);
256 int regcache_sync_region(struct regmap *map, unsigned int min,
257 			 unsigned int max);
258 void regcache_cache_only(struct regmap *map, bool enable);
259 void regcache_cache_bypass(struct regmap *map, bool enable);
260 void regcache_mark_dirty(struct regmap *map);
261 
262 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
263 			  int num_regs);
264 
265 /**
266  * Description of an IRQ for the generic regmap irq_chip.
267  *
268  * @reg_offset: Offset of the status/mask register within the bank
269  * @mask:       Mask used to flag/control the register.
270  */
271 struct regmap_irq {
272 	unsigned int reg_offset;
273 	unsigned int mask;
274 };
275 
276 /**
277  * Description of a generic regmap irq_chip.  This is not intended to
278  * handle every possible interrupt controller, but it should handle a
279  * substantial proportion of those that are found in the wild.
280  *
281  * @name:        Descriptive name for IRQ controller.
282  *
283  * @status_base: Base status register address.
284  * @mask_base:   Base mask register address.
285  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
286  * @wake_base:   Base address for wake enables.  If zero unsupported.
287  * @irq_reg_stride:  Stride to use for chips where registers are not contiguous.
288  *
289  * @num_regs:    Number of registers in each control bank.
290  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
291  *               assigned based on the index in the array of the interrupt.
292  * @num_irqs:    Number of descriptors.
293  */
294 struct regmap_irq_chip {
295 	const char *name;
296 
297 	unsigned int status_base;
298 	unsigned int mask_base;
299 	unsigned int ack_base;
300 	unsigned int wake_base;
301 	unsigned int irq_reg_stride;
302 
303 	int num_regs;
304 
305 	const struct regmap_irq *irqs;
306 	int num_irqs;
307 };
308 
309 struct regmap_irq_chip_data;
310 
311 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
312 			int irq_base, const struct regmap_irq_chip *chip,
313 			struct regmap_irq_chip_data **data);
314 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
315 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
316 int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq);
317 
318 #else
319 
320 /*
321  * These stubs should only ever be called by generic code which has
322  * regmap based facilities, if they ever get called at runtime
323  * something is going wrong and something probably needs to select
324  * REGMAP.
325  */
326 
327 static inline int regmap_write(struct regmap *map, unsigned int reg,
328 			       unsigned int val)
329 {
330 	WARN_ONCE(1, "regmap API is disabled");
331 	return -EINVAL;
332 }
333 
334 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
335 				   const void *val, size_t val_len)
336 {
337 	WARN_ONCE(1, "regmap API is disabled");
338 	return -EINVAL;
339 }
340 
341 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
342 				    const void *val, size_t val_count)
343 {
344 	WARN_ONCE(1, "regmap API is disabled");
345 	return -EINVAL;
346 }
347 
348 static inline int regmap_read(struct regmap *map, unsigned int reg,
349 			      unsigned int *val)
350 {
351 	WARN_ONCE(1, "regmap API is disabled");
352 	return -EINVAL;
353 }
354 
355 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
356 				  void *val, size_t val_len)
357 {
358 	WARN_ONCE(1, "regmap API is disabled");
359 	return -EINVAL;
360 }
361 
362 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
363 				   void *val, size_t val_count)
364 {
365 	WARN_ONCE(1, "regmap API is disabled");
366 	return -EINVAL;
367 }
368 
369 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
370 				     unsigned int mask, unsigned int val)
371 {
372 	WARN_ONCE(1, "regmap API is disabled");
373 	return -EINVAL;
374 }
375 
376 static inline int regmap_update_bits_check(struct regmap *map,
377 					   unsigned int reg,
378 					   unsigned int mask, unsigned int val,
379 					   bool *change)
380 {
381 	WARN_ONCE(1, "regmap API is disabled");
382 	return -EINVAL;
383 }
384 
385 static inline int regmap_get_val_bytes(struct regmap *map)
386 {
387 	WARN_ONCE(1, "regmap API is disabled");
388 	return -EINVAL;
389 }
390 
391 static inline int regcache_sync(struct regmap *map)
392 {
393 	WARN_ONCE(1, "regmap API is disabled");
394 	return -EINVAL;
395 }
396 
397 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
398 				       unsigned int max)
399 {
400 	WARN_ONCE(1, "regmap API is disabled");
401 	return -EINVAL;
402 }
403 
404 static inline void regcache_cache_only(struct regmap *map, bool enable)
405 {
406 	WARN_ONCE(1, "regmap API is disabled");
407 }
408 
409 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
410 {
411 	WARN_ONCE(1, "regmap API is disabled");
412 }
413 
414 static inline void regcache_mark_dirty(struct regmap *map)
415 {
416 	WARN_ONCE(1, "regmap API is disabled");
417 }
418 
419 static inline int regmap_register_patch(struct regmap *map,
420 					const struct reg_default *regs,
421 					int num_regs)
422 {
423 	WARN_ONCE(1, "regmap API is disabled");
424 	return -EINVAL;
425 }
426 
427 static inline struct regmap *dev_get_regmap(struct device *dev,
428 					    const char *name)
429 {
430 	return NULL;
431 }
432 
433 #endif
434 
435 #endif
436