LoCoMo chip contains a tiny i2c controller destined to control M62332 DAC. Provide a separate I2C driver for this cell.
Reviewed-by: Wolfram Sang wsa@the-dreams.de Signed-off-by: Dmitry Eremin-Solenikov dbaryshkov@gmail.com --- drivers/i2c/busses/Kconfig | 12 ++++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-locomo.c | 135 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 148 insertions(+) create mode 100644 drivers/i2c/busses/i2c-locomo.c
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 2255af2..114d9da 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -602,6 +602,18 @@ config I2C_KEMPLD This driver can also be built as a module. If so, the module will be called i2c-kempld.
+config I2C_LOCOMO + tristate "I2C bus support for LoCoMo chips" + depends on MFD_LOCOMO + select I2C_ALGOBIT + help + Say yes if you will run the kernel on Sharp SL-5x00 family of devices. + + If you don't know what to do here, say N. + + This driver can also be built as a module. If so, the module + will be called i2c-locomo. + config I2C_MESON tristate "Amlogic Meson I2C controller" depends on ARCH_MESON diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index cdf941d..e09dcf6 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -58,6 +58,7 @@ obj-$(CONFIG_I2C_IMX) += i2c-imx.o obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o obj-$(CONFIG_I2C_JZ4780) += i2c-jz4780.o obj-$(CONFIG_I2C_KEMPLD) += i2c-kempld.o +obj-$(CONFIG_I2C_LOCOMO) += i2c-locomo.o obj-$(CONFIG_I2C_MESON) += i2c-meson.o obj-$(CONFIG_I2C_MPC) += i2c-mpc.o obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o diff --git a/drivers/i2c/busses/i2c-locomo.c b/drivers/i2c/busses/i2c-locomo.c new file mode 100644 index 0000000..d520513 --- /dev/null +++ b/drivers/i2c/busses/i2c-locomo.c @@ -0,0 +1,135 @@ +/* + * 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/i2c.h> +#include <linux/i2c-algo-bit.h> +#include <linux/kernel.h> +#include <linux/mfd/locomo.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +struct locomo_i2c { + struct regmap *regmap; + struct i2c_adapter adap; + struct i2c_algo_bit_data bit; +}; + +static void locomo_i2c_setsda(void *data, int state) +{ + struct locomo_i2c *li2c = data; + + regmap_update_bits(li2c->regmap, LOCOMO_DAC, + LOCOMO_DAC_SDAOEB, + state ? LOCOMO_DAC_SDAOEB : 0); +} + +static void locomo_i2c_setscl(void *data, int state) +{ + struct locomo_i2c *li2c = data; + + regmap_update_bits(li2c->regmap, LOCOMO_DAC, + LOCOMO_DAC_SCLOEB, + state ? LOCOMO_DAC_SCLOEB : 0); +} + +static int locomo_i2c_getsda(void *data) +{ + struct locomo_i2c *li2c = data; + unsigned int r; + + regmap_read(li2c->regmap, LOCOMO_DAC, &r); + + return !!(r & LOCOMO_DAC_SDA); +} + +static int locomo_i2c_probe(struct platform_device *dev) +{ + struct locomo_i2c *li2c; + int ret; + + li2c = devm_kzalloc(&dev->dev, sizeof(struct locomo_i2c), GFP_KERNEL); + if (li2c == NULL) + return -ENOMEM; + + li2c->regmap = dev_get_regmap(dev->dev.parent, NULL); + if (!li2c->regmap) + return -ENODEV; + + li2c->adap.owner = THIS_MODULE; + li2c->adap.dev.parent = &dev->dev; + li2c->adap.dev.of_node = dev->dev.of_node; + li2c->adap.algo_data = &li2c->bit; + li2c->adap.nr = 1; /* On poodle, 0 is pxa internal bus */ + + strlcpy(li2c->adap.name, "LoCoMo I2C", sizeof(li2c->adap.name)); + + li2c->bit.data = li2c; + li2c->bit.setsda = locomo_i2c_setsda; + li2c->bit.setscl = locomo_i2c_setscl; + li2c->bit.getsda = locomo_i2c_getsda; + li2c->bit.udelay = 6; + li2c->bit.timeout = HZ; + + ret = i2c_bit_add_numbered_bus(&li2c->adap); + if (ret) + return ret; + + platform_set_drvdata(dev, li2c); + + return 0; +} + +static int locomo_i2c_remove(struct platform_device *dev) +{ + struct locomo_i2c *li2c = platform_get_drvdata(dev); + + i2c_del_adapter(&li2c->adap); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int locomo_i2c_suspend(struct device *dev) +{ + struct locomo_i2c *li2c = dev_get_drvdata(dev); + + regmap_write(li2c->regmap, LOCOMO_DAC, 0x00); + + return 0; +} + +static int locomo_i2c_resume(struct device *dev) +{ + struct locomo_i2c *li2c = dev_get_drvdata(dev); + + regmap_write(li2c->regmap, LOCOMO_DAC, + LOCOMO_DAC_SDAOEB | LOCOMO_DAC_SCLOEB); + + return 0; +} +static SIMPLE_DEV_PM_OPS(locomo_i2c_pm, locomo_i2c_suspend, locomo_i2c_resume); +#define LOCOMO_I2C_PM (&locomo_i2c_pm) +#else +#define LOCOMO_I2C_PM NULL +#endif + + +static struct platform_driver locomo_i2c_driver = { + .driver = { + .name = "locomo-i2c", + .pm = LOCOMO_I2C_PM, + }, + .probe = locomo_i2c_probe, + .remove = locomo_i2c_remove, +}; + +module_platform_driver(locomo_i2c_driver); + +MODULE_DESCRIPTION("LoCoMo i2c bus driver"); +MODULE_AUTHOR("Dmitry Eremin-Solenikov dbaryshkov@gmail.com"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:locomo-i2c");