diff options
| -rw-r--r-- | drivers/base/regmap/Kconfig | 4 | ||||
| -rw-r--r-- | drivers/base/regmap/Makefile | 1 | ||||
| -rw-r--r-- | drivers/base/regmap/regmap-i2c.c | 115 | ||||
| -rw-r--r-- | include/linux/regmap.h | 4 |
4 files changed, 124 insertions, 0 deletions
diff --git a/drivers/base/regmap/Kconfig b/drivers/base/regmap/Kconfig index fc0eb1d484dd..03cf1abed401 100644 --- a/drivers/base/regmap/Kconfig +++ b/drivers/base/regmap/Kconfig @@ -3,4 +3,8 @@ # subsystems should select the appropriate symbols. config REGMAP + default y if REGMAP_I2C bool + +config REGMAP_I2C + tristate diff --git a/drivers/base/regmap/Makefile b/drivers/base/regmap/Makefile index 7532e13e0f00..ee5109d20f4e 100644 --- a/drivers/base/regmap/Makefile +++ b/drivers/base/regmap/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_REGMAP) += regmap.o +obj-$(CONFIG_REGMAP_I2C) += regmap-i2c.o diff --git a/drivers/base/regmap/regmap-i2c.c b/drivers/base/regmap/regmap-i2c.c new file mode 100644 index 000000000000..c2231ff06cbc --- /dev/null +++ b/drivers/base/regmap/regmap-i2c.c @@ -0,0 +1,115 @@ +/* + * Register map access API - I2C support + * + * 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/regmap.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/init.h> + +static int regmap_i2c_write(struct device *dev, const void *data, size_t count) +{ + struct i2c_client *i2c = to_i2c_client(dev); + int ret; + + ret = i2c_master_send(i2c, data, count); + if (ret == count) + return 0; + else if (ret < 0) + return ret; + else + return -EIO; +} + +static int regmap_i2c_gather_write(struct device *dev, + const void *reg, size_t reg_size, + const void *val, size_t val_size) +{ + struct i2c_client *i2c = to_i2c_client(dev); + struct i2c_msg xfer[2]; + int ret; + + /* If the I2C controller can't do a gather tell the core, it + * will substitute in a linear write for us. + */ + if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_PROTOCOL_MANGLING)) + return -ENOTSUPP; + + xfer[0].addr = i2c->addr; + xfer[0].flags = 0; + xfer[0].len = reg_size; + xfer[0].buf = (void *)reg; + + xfer[1].addr = i2c->addr; + xfer[1].flags = I2C_M_NOSTART; + xfer[1].len = val_size; + xfer[1].buf = (void *)val; + + ret = i2c_transfer(i2c->adapter, xfer, 2); + if (ret == 2) + return 0; + if (ret < 0) + return ret; + else + return -EIO; +} + +static int regmap_i2c_read(struct device *dev, + const void *reg, size_t reg_size, + void *val, size_t val_size) +{ + struct i2c_client *i2c = to_i2c_client(dev); + struct i2c_msg xfer[2]; + int ret; + + xfer[0].addr = i2c->addr; + xfer[0].flags = 0; + xfer[0].len = reg_size; + xfer[0].buf = (void *)reg; + + xfer[1].addr = i2c->addr; + xfer[1].flags = I2C_M_RD; + xfer[1].len = val_size; + xfer[1].buf = val; + + ret = i2c_transfer(i2c->adapter, xfer, 2); + if (ret == 2) + return 0; + else if (ret < 0) + return ret; + else + return -EIO; +} + +static struct regmap_bus regmap_i2c = { + .type = &i2c_bus_type, + .write = regmap_i2c_write, + .gather_write = regmap_i2c_gather_write, + .read = regmap_i2c_read, + .owner = THIS_MODULE, +}; + +/** + * regmap_init_i2c(): Initialise register map + * + * @i2c: Device that will be interacted with + * @config: Configuration for register map + * + * The return value will be an ERR_PTR() on error or a valid pointer to + * a struct regmap. + */ +struct regmap *regmap_init_i2c(struct i2c_client *i2c, + const struct regmap_config *config) +{ + return regmap_init(&i2c->dev, ®map_i2c, config); +} +EXPORT_SYMBOL_GPL(regmap_init_i2c); + diff --git a/include/linux/regmap.h b/include/linux/regmap.h index a26c1d001401..5ba61f22c703 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -17,6 +17,8 @@ #include <linux/list.h> #include <linux/module.h> +struct i2c_client; + struct regmap_config { int reg_bits; int val_bits; @@ -59,6 +61,8 @@ struct regmap_bus { 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); 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, |