mfd: tps65912: Add new mfd device

The tps65912 chip is a power management IC. It contains the following
components:

- Regulators
- GPIO controller

The core driver is registered as a platform driver, it provides communication
through I2C and SPI interfaces.

Signed-off-by: Margarita Olaya Cabrera <magi@slimlogic.co.uk>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/tps65912-spi.c b/drivers/mfd/tps65912-spi.c
new file mode 100644
index 0000000..6d71e0d
--- /dev/null
+++ b/drivers/mfd/tps65912-spi.c
@@ -0,0 +1,142 @@
+/*
+ * tps65912-spi.c  --  SPI access for TI TPS65912x PMIC
+ *
+ * Copyright 2011 Texas Instruments Inc.
+ *
+ * Author: Margarita Olaya Cabrera <magi@slimlogic.co.uk>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ *  This driver is based on wm8350 implementation.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/spi/spi.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/tps65912.h>
+
+static int tps65912_spi_write(struct tps65912 *tps65912, u8 addr,
+							int bytes, void *src)
+{
+	struct spi_device *spi = tps65912->control_data;
+	u8 *data = (u8 *) src;
+	int ret;
+	/* bit 23 is the read/write bit */
+	unsigned long spi_data = 1 << 23 | addr << 15 | *data;
+	struct spi_transfer xfer;
+	struct spi_message msg;
+	u32 tx_buf, rx_buf;
+
+	tx_buf = spi_data;
+	rx_buf = 0;
+
+	xfer.tx_buf	= &tx_buf;
+	xfer.rx_buf	= NULL;
+	xfer.len	= sizeof(unsigned long);
+	xfer.bits_per_word = 24;
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+
+	ret = spi_sync(spi, &msg);
+	return ret;
+}
+
+static int tps65912_spi_read(struct tps65912 *tps65912, u8 addr,
+							int bytes, void *dest)
+{
+	struct spi_device *spi = tps65912->control_data;
+	/* bit 23 is the read/write bit */
+	unsigned long spi_data = 0 << 23 | addr << 15;
+	struct spi_transfer xfer;
+	struct spi_message msg;
+	int ret;
+	u8 *data = (u8 *) dest;
+	u32 tx_buf, rx_buf;
+
+	tx_buf = spi_data;
+	rx_buf = 0;
+
+	xfer.tx_buf	= &tx_buf;
+	xfer.rx_buf	= &rx_buf;
+	xfer.len	= sizeof(unsigned long);
+	xfer.bits_per_word = 24;
+
+	spi_message_init(&msg);
+	spi_message_add_tail(&xfer, &msg);
+
+	if (spi == NULL)
+		return 0;
+
+	ret = spi_sync(spi, &msg);
+	if (ret == 0)
+		*data = (u8) (rx_buf & 0xFF);
+	return ret;
+}
+
+static int __devinit tps65912_spi_probe(struct spi_device *spi)
+{
+	struct tps65912 *tps65912;
+
+	tps65912 = kzalloc(sizeof(struct tps65912), GFP_KERNEL);
+	if (tps65912 == NULL)
+		return -ENOMEM;
+
+	tps65912->dev = &spi->dev;
+	tps65912->control_data = spi;
+	tps65912->read = tps65912_spi_read;
+	tps65912->write = tps65912_spi_write;
+
+	spi_set_drvdata(spi, tps65912);
+
+	return tps65912_device_init(tps65912);
+}
+
+static int __devexit tps65912_spi_remove(struct spi_device *spi)
+{
+	struct tps65912 *tps65912 = spi_get_drvdata(spi);
+
+	tps65912_device_exit(tps65912);
+
+	return 0;
+}
+
+static struct spi_driver tps65912_spi_driver = {
+	.driver = {
+		.name = "tps65912",
+		.bus = &spi_bus_type,
+		.owner = THIS_MODULE,
+	},
+	.probe	= tps65912_spi_probe,
+	.remove = __devexit_p(tps65912_spi_remove),
+};
+
+static int __init tps65912_spi_init(void)
+{
+	int ret;
+
+	ret = spi_register_driver(&tps65912_spi_driver);
+	if (ret != 0)
+		pr_err("Failed to register TPS65912 SPI driver: %d\n", ret);
+
+	return 0;
+}
+/* init early so consumer devices can complete system boot */
+subsys_initcall(tps65912_spi_init);
+
+static void __exit tps65912_spi_exit(void)
+{
+	spi_unregister_driver(&tps65912_spi_driver);
+}
+module_exit(tps65912_spi_exit);
+
+MODULE_AUTHOR("Margarita Olaya	<magi@slimlogic.co.uk>");
+MODULE_DESCRIPTION("SPI support for TPS65912 chip family mfd");
+MODULE_LICENSE("GPL");