2 * Register map access API - I2C support
4 * Copyright 2011 Wolfson Microelectronics plc
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/regmap.h>
14 #include <linux/i2c.h>
15 #include <linux/module.h>
17 static int regmap_i2c_write(void *context, const void *data, size_t count)
19 struct device *dev = context;
20 struct i2c_client *i2c = to_i2c_client(dev);
23 ret = i2c_master_send(i2c, data, count);
32 static int regmap_i2c_gather_write(void *context,
33 const void *reg, size_t reg_size,
34 const void *val, size_t val_size)
36 struct device *dev = context;
37 struct i2c_client *i2c = to_i2c_client(dev);
38 struct i2c_msg xfer[2];
41 /* If the I2C controller can't do a gather tell the core, it
42 * will substitute in a linear write for us.
44 if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_NOSTART))
47 xfer[0].addr = i2c->addr;
49 xfer[0].len = reg_size;
50 xfer[0].buf = (void *)reg;
52 xfer[1].addr = i2c->addr;
53 xfer[1].flags = I2C_M_NOSTART;
54 xfer[1].len = val_size;
55 xfer[1].buf = (void *)val;
57 ret = i2c_transfer(i2c->adapter, xfer, 2);
66 static int regmap_i2c_read(void *context,
67 const void *reg, size_t reg_size,
68 void *val, size_t val_size)
70 struct device *dev = context;
71 struct i2c_client *i2c = to_i2c_client(dev);
72 struct i2c_msg xfer[2];
75 xfer[0].addr = i2c->addr;
77 xfer[0].len = reg_size;
78 xfer[0].buf = (void *)reg;
80 xfer[1].addr = i2c->addr;
81 xfer[1].flags = I2C_M_RD;
82 xfer[1].len = val_size;
85 ret = i2c_transfer(i2c->adapter, xfer, 2);
94 static struct regmap_bus regmap_i2c = {
95 .write = regmap_i2c_write,
96 .gather_write = regmap_i2c_gather_write,
97 .read = regmap_i2c_read,
101 * regmap_init_i2c(): Initialise register map
103 * @i2c: Device that will be interacted with
104 * @config: Configuration for register map
106 * The return value will be an ERR_PTR() on error or a valid pointer to
109 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
110 const struct regmap_config *config)
112 return regmap_init(&i2c->dev, ®map_i2c, &i2c->dev, config);
114 EXPORT_SYMBOL_GPL(regmap_init_i2c);
117 * devm_regmap_init_i2c(): Initialise managed register map
119 * @i2c: Device that will be interacted with
120 * @config: Configuration for register map
122 * The return value will be an ERR_PTR() on error or a valid pointer
123 * to a struct regmap. The regmap will be automatically freed by the
124 * device management code.
126 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
127 const struct regmap_config *config)
129 return devm_regmap_init(&i2c->dev, ®map_i2c, &i2c->dev, config);
131 EXPORT_SYMBOL_GPL(devm_regmap_init_i2c);
133 MODULE_LICENSE("GPL");