summaryrefslogtreecommitdiff
path: root/include/linux/regmap.h
blob: 690276a642cf75dd5dbfcd1d620b8a94880714fc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
#ifndef __LINUX_REGMAP_H
#define __LINUX_REGMAP_H

/*
 * Register map access API
 *
 * Copyright 2011 Wolfson Microelectronics plc
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/device.h>
#include <linux/list.h>

struct module;
struct i2c_client;
struct spi_device;

/* An enum of all the supported cache types */
enum regcache_type {
	REGCACHE_NONE,
	REGCACHE_INDEXED,
	REGCACHE_RBTREE,
	REGCACHE_LZO
};

/**
 * Default value for a register.  We use an array of structs rather
 * than a simple array as many modern devices have very sparse
 * register maps.
 *
 * @reg: Register address.
 * @def: Register default value.
 */
struct reg_default {
	unsigned int reg;
	unsigned int def;
};

/**
 * Configuration for the register map of a device.
 *
 * @reg_bits: Number of bits in a register address, mandatory.
 * @val_bits: Number of bits in a register value, mandatory.
 *
 * @writeable_reg: Optional callback returning true if the register
 *                 can be written to.
 * @readable_reg: Optional callback returning true if the register
 *                can be read from.
 * @volatile_reg: Optional callback returning true if the register
 *                value can't be cached.
 * @precious_reg: Optional callback returning true if the rgister
 *                should not be read outside of a call from the driver
 *                (eg, a clear on read interrupt status register).
 *
 * @max_register: Optional, specifies the maximum valid register index.
 * @reg_defaults: Power on reset values for registers (for use with
 *                register cache support).
 * @num_reg_defaults: Number of elements in reg_defaults.
 *
 * @read_flag_mask: Mask to be set in the top byte of the register when doing
 *                  a read.
 * @write_flag_mask: Mask to be set in the top byte of the register when doing
 *                   a write. If both read_flag_mask and write_flag_mask are
 *                   empty the regmap_bus default masks are used.
 *
 * @cache_type: The actual cache type.
 * @reg_defaults_raw: Power on reset values for registers (for use with
 *                    register cache support).
 * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
 */
struct regmap_config {
	int reg_bits;
	int val_bits;

	bool (*writeable_reg)(struct device *dev, unsigned int reg);
	bool (*readable_reg)(struct device *dev, unsigned int reg);
	bool (*volatile_reg)(struct device *dev, unsigned int reg);
	bool (*precious_reg)(struct device *dev, unsigned int reg);

	unsigned int max_register;
	struct reg_default *reg_defaults;
	unsigned int num_reg_defaults;
	enum regcache_type cache_type;
	const void *reg_defaults_raw;
	unsigned int num_reg_defaults_raw;

	u8 read_flag_mask;
	u8 write_flag_mask;
};

typedef int (*regmap_hw_write)(struct device *dev, const void *data,
			       size_t count);
typedef int (*regmap_hw_gather_write)(struct device *dev,
				      const void *reg, size_t reg_len,
				      const void *val, size_t val_len);
typedef int (*regmap_hw_read)(struct device *dev,
			      const void *reg_buf, size_t reg_size,
			      void *val_buf, size_t val_size);

/**
 * Description of a hardware bus for the register map infrastructure.
 *
 * @write: Write operation.
 * @gather_write: Write operation with split register/value, return -ENOTSUPP
 *                if not implemented  on a given device.
 * @read: Read operation.  Data is returned in the buffer used to transmit
 *         data.
 * @read_flag_mask: Mask to be set in the top byte of the register when doing
 *                  a read.
 */
struct regmap_bus {
	regmap_hw_write write;
	regmap_hw_gather_write gather_write;
	regmap_hw_read read;
	u8 read_flag_mask;
};

struct regmap *regmap_init(struct device *dev,
			   const struct regmap_bus *bus,
			   const struct regmap_config *config);
struct regmap *regmap_init_i2c(struct i2c_client *i2c,
			       const struct regmap_config *config);
struct regmap *regmap_init_spi(struct spi_device *dev,
			       const struct regmap_config *config);

void regmap_exit(struct regmap *map);
int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
int regmap_raw_write(struct regmap *map, unsigned int reg,
		     const void *val, size_t val_len);
int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
int regmap_raw_read(struct regmap *map, unsigned int reg,
		    void *val, size_t val_len);
int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
		     size_t val_count);
int regmap_update_bits(struct regmap *map, unsigned int reg,
		       unsigned int mask, unsigned int val);

int regcache_sync(struct regmap *map);
void regcache_cache_only(struct regmap *map, bool enable);
void regcache_cache_bypass(struct regmap *map, bool enable);

#endif