Messages in this thread Patch in this message | | | From | Mark Brown <> | Subject | [PATCH 2/4] regmap: Add I2C bus support | Date | Sat, 16 Jul 2011 11:48:38 +0900 |
| |
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Liam Girdwood <lrg@ti.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> --- MAINTAINERS | 1 + drivers/i2c/Kconfig | 4 ++ drivers/i2c/Makefile | 1 + drivers/i2c/i2c-regmap.c | 115 ++++++++++++++++++++++++++++++++++++++++++++++ include/linux/regmap.h | 2 + 5 files changed, 123 insertions(+), 0 deletions(-) create mode 100644 drivers/i2c/i2c-regmap.c
diff --git a/MAINTAINERS b/MAINTAINERS index b7eaf63..21d7698 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5318,6 +5318,7 @@ M: Mark Brown <broonie@opensource.wolfsonmicro.com> T: git git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git S: Supported F: drivers/base/regmap/ +F: drivers/i2c/i2c-regmap.c F: include/linux/regmap.h RFKILL diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig index 30f06e9..cba758b 100644 --- a/drivers/i2c/Kconfig +++ b/drivers/i2c/Kconfig @@ -6,6 +6,7 @@ menuconfig I2C tristate "I2C support" depends on HAS_IOMEM select RT_MUTEXES + select I2C_REGMAP if REGMAP ---help--- I2C (pronounce: I-square-C) is a slow serial bus protocol used in many micro controller applications and developed by Philips. SMBus, @@ -110,4 +111,7 @@ config I2C_DEBUG_BUS a problem with I2C support and want to see more of what is going on. +config I2C_REGMAP + tristate + endif # I2C diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index beee6b2..85d6699 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_I2C) += i2c-core.o obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o obj-$(CONFIG_I2C_MUX) += i2c-mux.o +obj-$(CONFIG_I2C_REGMAP) += i2c-regmap.o obj-y += algos/ busses/ muxes/ ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG diff --git a/drivers/i2c/i2c-regmap.c b/drivers/i2c/i2c-regmap.c new file mode 100644 index 0000000..6237003 --- /dev/null +++ b/drivers/i2c/i2c-regmap.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 + * + * @dev: 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 device *dev, + const struct regmap_config *config) +{ + return regmap_init(dev, ®map_i2c, config); +} +EXPORT_SYMBOL_GPL(regmap_init_i2c); + diff --git a/include/linux/regmap.h b/include/linux/regmap.h index a26c1d0..e509bac 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -59,6 +59,8 @@ 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 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, -- 1.7.5.4
| |