[PATCH 3/3] mfd: mc13xxx-core: Add i2c driver

[Marc Reilly]

Adds support for mc13xxx family ICs connected via i2c.

Signed-off-by: Marc Reilly <marc at cpdesign.com.au>
---
 drivers/mfd/Kconfig         |    8 +++-
 drivers/mfd/Makefile        |    1 +
 drivers/mfd/mc13xxx-i2c.c   |  120 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/mfd/mc13xxx.h |    5 ++-
 4 files changed, 132 insertions(+), 2 deletions(-)
 create mode 100644 drivers/mfd/mc13xxx-i2c.c

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 6cf84c8..08afc84 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -515,7 +515,7 @@ config MFD_MC13783
 
 config MFD_MC13XXX
 	tristate "Support Freescale MC13783 or MC13892"
-	depends on SPI_MASTER
+	depends on SPI_MASTER || I2C
 	select MFD_CORE
 	select MFD_MC13783
 	help
@@ -538,6 +538,12 @@ config MFD_MC13XXX_SPI
 	help
 	  Select this if your MC13xxx is connected via an SPI bus.
 
+config MFD_MC13XXX_I2C
+	tristate "I2C interface"
+	depends on I2C
+	help
+	  Select this if your MC13xxx is connected via an I2C bus.
+
 endchoice
 
 config ABX500_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 3856820..5db8b76 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_TWL6040_CORE)	+= twl6040-core.o twl6040-irq.o
 
 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..9965481
--- /dev/null
+++ b/drivers/mfd/mc13xxx-i2c.c
@@ -0,0 +1,120 @@
+/*
+ * Copyright 2009-2010 Creative Product Design
+ * Marc Reilly marc at 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/i2c.h>
+
+static int mc13xxx_i2c_reg_read(struct mc13xxx *mc13xxx, unsigned int offset,
+		u32 *val)
+{
+	int ret;
+	unsigned char buf[3] = {0, 0, 0};
+
+	ret = i2c_smbus_read_i2c_block_data(mc13xxx->i2cclient,
+			offset, 3, buf);
+	*val = buf[0] << 16 | buf[1] << 8 | buf[2];
+
+	return ret == 3 ? 0 : ret;
+}
+
+static int mc13xxx_i2c_reg_write(struct mc13xxx *mc13xxx, unsigned int offset,
+		u32 val)
+{
+	int ret;
+	unsigned char buf[3];
+
+	buf[0] = (val >> 16) & 0xff;
+	buf[1] = (val >> 8) & 0xff;
+	buf[2] = val & 0xff;
+
+	ret = i2c_smbus_write_i2c_block_data(mc13xxx->i2cclient,
+			offset, 3, buf);
+
+	return ret;
+}
+
+static int mc13xxx_i2c_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	struct mc13xxx *mc13xxx;
+	struct mc13xxx_platform_data *pdata = dev_get_platdata(&client->dev);
+	int ret;
+
+	if (!pdata) {
+		dev_err(&client->dev, "invalid platform data\n");
+		return -EINVAL;
+	}
+
+	mc13xxx = kzalloc(sizeof(*mc13xxx), GFP_KERNEL);
+	if (!mc13xxx)
+		return -ENOMEM;
+
+	dev_set_drvdata(&client->dev, mc13xxx);
+	mc13xxx->dev = &client->dev;
+	mc13xxx->i2cclient = client;
+	mc13xxx->read_dev = mc13xxx_i2c_reg_read;
+	mc13xxx->write_dev = mc13xxx_i2c_reg_write;
+
+	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);
+
+	free_irq(client->irq, mc13xxx);
+
+	mfd_remove_devices(&client->dev);
+
+	kfree(mc13xxx);
+
+	return 0;
+}
+
+static const struct i2c_device_id mc13xxx_i2c_idtable[] = {
+	{"mc13892", MC13XXX_ID_MC13892},
+	{ }
+};
+
+static struct i2c_driver mc13xxx_i2c_driver = {
+	.driver = {
+		.owner = THIS_MODULE,
+		.name = "mc13xxx-i2c"
+	},
+	.id_table = mc13xxx_i2c_idtable,
+	.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 at cpdesign.com.au");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mfd/mc13xxx.h b/include/linux/mfd/mc13xxx.h
index abf77d3..c17fc60 100644
--- a/include/linux/mfd/mc13xxx.h
+++ b/include/linux/mfd/mc13xxx.h
@@ -76,7 +76,10 @@ enum mc13xxx_id {
 };
 
 struct mc13xxx {
-	struct spi_device *spidev;
+	union {
+		struct spi_device *spidev;
+		struct i2c_client *i2cclient;
+	};
 
 	struct device *dev;
 	enum mc13xxx_id ictype;
-- 
1.7.3.4