mfd: Add mc13xxx i2c driver

Adds support for mc13xxx family ICs connected via i2c.

Signed-off-by: Marc Reilly <marc@cpdesign.com.au>
Acked-by: Oskar Schirmer <oskar@scara.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 9c8294c..ef86a74 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -597,7 +597,7 @@
 
 config MFD_MC13XXX
 	tristate "Support Freescale MC13783 and MC13892"
-	depends on SPI_MASTER
+	depends on SPI_MASTER || I2C
 	select MFD_CORE
 	select MFD_MC13783
 	help
@@ -615,6 +615,13 @@
 	help
 	  Select this if your MC13xxx is connected via an SPI bus.
 
+config MFD_MC13XXX_I2C
+	tristate "MC13xxx I2C interface" if I2C
+	default I2C
+	select REGMAP_I2C
+	help
+	  Select this if your MC13xxx is connected via an I2C bus.
+
 endif
 
 config ABX500_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 7ce5b5c..5dd6be7 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -55,6 +55,7 @@
 
 obj-$(CONFIG_MFD_MC13XXX)	+= mc13xxx-core.o
 obj-$(CONFIG_MFD_MC13XXX_SPI)	+= mc13xxx-spi.o
+obj-$(CONFIG_MFD_MC13XXX_I2C)	+= mc13xxx-i2c.o
 
 obj-$(CONFIG_MFD_CORE)		+= mfd-core.o
 
diff --git a/drivers/mfd/mc13xxx-i2c.c b/drivers/mfd/mc13xxx-i2c.c
new file mode 100644
index 0000000..d22501d
--- /dev/null
+++ b/drivers/mfd/mc13xxx-i2c.c
@@ -0,0 +1,128 @@
+/*
+ * Copyright 2009-2010 Creative Product Design
+ * Marc Reilly marc@cpdesign.com.au
+ *
+ * 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/slab.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/mc13xxx.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+
+#include "mc13xxx.h"
+
+static const struct i2c_device_id mc13xxx_i2c_device_id[] = {
+	{
+		.name = "mc13892",
+		.driver_data = MC13XXX_ID_MC13892,
+	}, {
+		/* sentinel */
+	}
+};
+MODULE_DEVICE_TABLE(i2c, mc13xxx_i2c_device_id);
+
+static const struct of_device_id mc13xxx_dt_ids[] = {
+	{
+		.compatible = "fsl,mc13892",
+		.data = (void *) &mc13xxx_i2c_device_id[0],
+	}, {
+		/* sentinel */
+	}
+};
+MODULE_DEVICE_TABLE(of, mc13xxx_dt_ids);
+
+static struct regmap_config mc13xxx_regmap_i2c_config = {
+	.reg_bits = 8,
+	.val_bits = 24,
+
+	.max_register = MC13XXX_NUMREGS,
+
+	.cache_type = REGCACHE_NONE,
+};
+
+static int mc13xxx_i2c_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	const struct of_device_id *of_id;
+	struct i2c_driver *idrv = to_i2c_driver(client->dev.driver);
+	struct mc13xxx *mc13xxx;
+	struct mc13xxx_platform_data *pdata = dev_get_platdata(&client->dev);
+	int ret;
+
+	of_id = of_match_device(mc13xxx_dt_ids, &client->dev);
+	if (of_id)
+		idrv->id_table = (const struct i2c_device_id*) of_id->data;
+
+	mc13xxx = kzalloc(sizeof(*mc13xxx), GFP_KERNEL);
+	if (!mc13xxx)
+		return -ENOMEM;
+
+	dev_set_drvdata(&client->dev, mc13xxx);
+
+	mc13xxx->dev = &client->dev;
+	mutex_init(&mc13xxx->lock);
+
+	mc13xxx->regmap = regmap_init_i2c(client, &mc13xxx_regmap_i2c_config);
+	if (IS_ERR(mc13xxx->regmap)) {
+		ret = PTR_ERR(mc13xxx->regmap);
+		dev_err(mc13xxx->dev, "Failed to initialize register map: %d\n",
+				ret);
+		dev_set_drvdata(&client->dev, NULL);
+		kfree(mc13xxx);
+		return ret;
+	}
+
+	ret = mc13xxx_common_init(mc13xxx, pdata, client->irq);
+
+	if (ret == 0 && (id->driver_data != mc13xxx->ictype))
+		dev_warn(mc13xxx->dev,
+				"device id doesn't match auto detection!\n");
+
+	return ret;
+}
+
+static int __devexit mc13xxx_i2c_remove(struct i2c_client *client)
+{
+	struct mc13xxx *mc13xxx = dev_get_drvdata(&client->dev);
+
+	mc13xxx_common_cleanup(mc13xxx);
+
+	return 0;
+}
+
+static struct i2c_driver mc13xxx_i2c_driver = {
+	.id_table = mc13xxx_i2c_device_id,
+	.driver = {
+		.owner = THIS_MODULE,
+		.name = "mc13xxx",
+		.of_match_table = mc13xxx_dt_ids,
+	},
+	.probe = mc13xxx_i2c_probe,
+	.remove = __devexit_p(mc13xxx_i2c_remove),
+};
+
+static int __init mc13xxx_i2c_init(void)
+{
+	return i2c_add_driver(&mc13xxx_i2c_driver);
+}
+subsys_initcall(mc13xxx_i2c_init);
+
+static void __exit mc13xxx_i2c_exit(void)
+{
+	i2c_del_driver(&mc13xxx_i2c_driver);
+}
+module_exit(mc13xxx_i2c_exit);
+
+MODULE_DESCRIPTION("i2c driver for Freescale MC13XXX PMIC");
+MODULE_AUTHOR("Marc Reilly <marc@cpdesign.com.au");
+MODULE_LICENSE("GPL v2");