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>
16 #include <linux/init.h>
18 static int regmap_i2c_write(struct device *dev, const void *data, size_t count)
20 struct i2c_client *i2c = to_i2c_client(dev);
23 ret = i2c_master_send(i2c, data, count);
32 static int regmap_i2c_gather_write(struct device *dev,
33 const void *reg, size_t reg_size,
34 const void *val, size_t val_size)
36 struct i2c_client *i2c = to_i2c_client(dev);
37 struct i2c_msg xfer[2];
40 /* If the I2C controller can't do a gather tell the core, it
41 * will substitute in a linear write for us.
43 if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_PROTOCOL_MANGLING))
46 xfer[0].addr = i2c->addr;
48 xfer[0].len = reg_size;
49 xfer[0].buf = (void *)reg;
51 xfer[1].addr = i2c->addr;
52 xfer[1].flags = I2C_M_NOSTART;
53 xfer[1].len = val_size;
54 xfer[1].buf = (void *)val;
56 ret = i2c_transfer(i2c->adapter, xfer, 2);
65 static int regmap_i2c_read(struct device *dev,
66 const void *reg, size_t reg_size,
67 void *val, size_t val_size)
69 struct i2c_client *i2c = to_i2c_client(dev);
70 struct i2c_msg xfer[2];
73 xfer[0].addr = i2c->addr;
75 xfer[0].len = reg_size;
76 xfer[0].buf = (void *)reg;
78 xfer[1].addr = i2c->addr;
79 xfer[1].flags = I2C_M_RD;
80 xfer[1].len = val_size;
83 ret = i2c_transfer(i2c->adapter, xfer, 2);
92 static struct regmap_bus regmap_i2c = {
93 .write = regmap_i2c_write,
94 .gather_write = regmap_i2c_gather_write,
95 .read = regmap_i2c_read,
100 * regmap_init_i2c(): Initialise register map
102 * @i2c: Device that will be interacted with
103 * @config: Configuration for register map
105 * The return value will be an ERR_PTR() on error or a valid pointer to
108 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
109 const struct regmap_config *config)
111 return regmap_init(&i2c->dev, ®map_i2c, config);
113 EXPORT_SYMBOL_GPL(regmap_init_i2c);
115 MODULE_LICENSE("GPL");