mfd: Add TPS6507x support

TPS6507x are multi function (PM, touchscreen) chipsets from TI.
This commit also changes the corresponding regulator driver from being
standalone to an MFD subdevice.

Signed-off-by: Todd Fischer <todd.fischer@ridgerun.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/tps6507x.c b/drivers/mfd/tps6507x.c
new file mode 100644
index 0000000..c59f745
--- /dev/null
+++ b/drivers/mfd/tps6507x.c
@@ -0,0 +1,156 @@
+/*
+ * tps6507x.c  --  TPS6507x chip family multi-function driver
+ *
+ *  Copyright (c) 2010 RidgeRun (todd.fischer@ridgerun.com)
+ *
+ * Author: Todd Fischer
+ *         todd.fischer@ridgerun.com
+ *
+ * Credits:
+ *
+ *    Using code from wm831x-*.c, wm8400-core, Wolfson Microelectronics PLC.
+ *
+ * For licencing details see kernel-base/COPYING
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/tps6507x.h>
+
+static struct mfd_cell tps6507x_devs[] = {
+	{
+		.name = "tps6507x-pmic",
+	},
+};
+
+
+static int tps6507x_i2c_read_device(struct tps6507x_dev *tps6507x, char reg,
+				  int bytes, void *dest)
+{
+	struct i2c_client *i2c = tps6507x->i2c_client;
+	struct i2c_msg xfer[2];
+	int ret;
+
+	/* Write register */
+	xfer[0].addr = i2c->addr;
+	xfer[0].flags = 0;
+	xfer[0].len = 1;
+	xfer[0].buf = &reg;
+
+	/* Read data */
+	xfer[1].addr = i2c->addr;
+	xfer[1].flags = I2C_M_RD;
+	xfer[1].len = bytes;
+	xfer[1].buf = dest;
+
+	ret = i2c_transfer(i2c->adapter, xfer, 2);
+	if (ret == 2)
+		ret = 0;
+	else if (ret >= 0)
+		ret = -EIO;
+
+	return ret;
+}
+
+static int tps6507x_i2c_write_device(struct tps6507x_dev *tps6507x, char reg,
+				   int bytes, void *src)
+{
+	struct i2c_client *i2c = tps6507x->i2c_client;
+	/* we add 1 byte for device register */
+	u8 msg[TPS6507X_MAX_REGISTER + 1];
+	int ret;
+
+	if (bytes > (TPS6507X_MAX_REGISTER + 1))
+		return -EINVAL;
+
+	msg[0] = reg;
+	memcpy(&msg[1], src, bytes);
+
+	ret = i2c_master_send(i2c, msg, bytes + 1);
+	if (ret < 0)
+		return ret;
+	if (ret != bytes + 1)
+		return -EIO;
+	return 0;
+}
+
+static int tps6507x_i2c_probe(struct i2c_client *i2c,
+			    const struct i2c_device_id *id)
+{
+	struct tps6507x_dev *tps6507x;
+	int ret = 0;
+
+	tps6507x = kzalloc(sizeof(struct tps6507x_dev), GFP_KERNEL);
+	if (tps6507x == NULL) {
+		kfree(i2c);
+		return -ENOMEM;
+	}
+
+	i2c_set_clientdata(i2c, tps6507x);
+	tps6507x->dev = &i2c->dev;
+	tps6507x->i2c_client = i2c;
+	tps6507x->read_dev = tps6507x_i2c_read_device;
+	tps6507x->write_dev = tps6507x_i2c_write_device;
+
+	ret = mfd_add_devices(tps6507x->dev, -1,
+			      tps6507x_devs, ARRAY_SIZE(tps6507x_devs),
+			      NULL, 0);
+
+	if (ret < 0)
+		goto err;
+
+	return ret;
+
+err:
+	mfd_remove_devices(tps6507x->dev);
+	kfree(tps6507x);
+	return ret;
+}
+
+static int tps6507x_i2c_remove(struct i2c_client *i2c)
+{
+	struct tps6507x_dev *tps6507x = i2c_get_clientdata(i2c);
+
+	mfd_remove_devices(tps6507x->dev);
+	kfree(tps6507x);
+
+	return 0;
+}
+
+static const struct i2c_device_id tps6507x_i2c_id[] = {
+       { "tps6507x", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, tps6507x_i2c_id);
+
+
+static struct i2c_driver tps6507x_i2c_driver = {
+	.driver = {
+		   .name = "tps6507x",
+		   .owner = THIS_MODULE,
+	},
+	.probe = tps6507x_i2c_probe,
+	.remove = tps6507x_i2c_remove,
+	.id_table = tps6507x_i2c_id,
+};
+
+static int __init tps6507x_i2c_init(void)
+{
+	return i2c_add_driver(&tps6507x_i2c_driver);
+}
+/* init early so consumer devices can complete system boot */
+subsys_initcall(tps6507x_i2c_init);
+
+static void __exit tps6507x_i2c_exit(void)
+{
+	i2c_del_driver(&tps6507x_i2c_driver);
+}
+module_exit(tps6507x_i2c_exit);
+
+MODULE_DESCRIPTION("TPS6507x chip family multi-function driver");
+MODULE_LICENSE("GPL");