twl-core: abstract twl4030 and add twlcore driver

Add a general twl device driver twlcore to call i2c send/write
functions.
Abstract twl4030 to call twlcore functions.

Fixed some code-styling issues pointed out by checkpatch.

Signed-off-by: Alexander Aring <a.aring@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 157 insertions, 0 deletions

diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
new file mode 100644
index 0000000000..cb2c03dfca
--- /dev/null
+++ b/drivers/mfd/twl-core.c
@@ -0,0 +1,157 @@
+/*
+ * Copyright (C) 2011 Alexander Aring <a.aring@phytec.de>
+ *
+ * Based on:
+ * Copyright (C) 2010 Michael Grzeschik <mgr@pengutronix.de>
+ *
+ * This file is released under the GPLv2
+ *
+ */
+
+#include <common.h>
+#include <init.h>
+#include <driver.h>
+#include <xfuncs.h>
+#include <errno.h>
+
+#include <i2c/i2c.h>
+#include <mfd/twl-core.h>
+
+#define to_twlcore(a)       container_of(a, struct twlcore, cdev)
+
+static struct twlcore *twl_dev;
+
+struct twlcore *twlcore_get(void)
+{
+	return twl_dev;
+}
+EXPORT_SYMBOL(twlcore_get);
+
+int twlcore_reg_read(struct twlcore *twlcore, u16 reg, u8 *val)
+{
+	int ret;
+	struct i2c_msg xfer_msg[2];
+	struct i2c_msg *msg;
+	int i2c_addr;
+	unsigned char buf = reg & 0xff;
+
+	i2c_addr = twlcore->client->addr + (reg / 0x100);
+
+	/* [MSG1] fill the register address data */
+	msg = &xfer_msg[0];
+	msg->addr = i2c_addr;
+	msg->len = 1;
+	msg->flags = 0;
+	msg->buf = &buf;
+	/* [MSG2] fill the data rx buffer */
+	msg = &xfer_msg[1];
+	msg->addr = i2c_addr;
+	msg->flags = I2C_M_RD;
+	msg->len = 1;	/* only n bytes */
+	msg->buf = val;
+	ret = i2c_transfer(twlcore->client->adapter, xfer_msg, 2);
+
+	/* i2c_transfer returns number of messages transferred */
+	if (ret < 0) {
+		pr_err("%s: failed to transfer all messages: %s\n",
+				__func__, strerror(-ret));
+		return ret;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(twlcore_reg_read);
+
+int twlcore_reg_write(struct twlcore *twlcore, u16 reg, u8 val)
+{
+	int ret;
+	struct i2c_msg xfer_msg[1];
+	struct i2c_msg *msg;
+	int i2c_addr;
+	u8 buf[2];
+
+	buf[0] = reg & 0xff;
+	buf[1] = val;
+
+	i2c_addr = twlcore->client->addr + (reg / 0x100);
+
+	/*
+	 * [MSG1]: fill the register address data
+	 * fill the data Tx buffer
+	 */
+	msg = xfer_msg;
+	msg->addr = i2c_addr;
+	msg->len = 2;
+	msg->flags = 0;
+	msg->buf = buf;
+	/* over write the first byte of buffer with the register address */
+	ret = i2c_transfer(twlcore->client->adapter, xfer_msg, 1);
+
+	/* i2c_transfer returns number of messages transferred */
+	if (ret < 0) {
+		pr_err("%s: failed to transfer all messages: %s\n",
+				__func__, strerror(-ret));
+		return ret;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(twlcore_reg_write);
+
+int twlcore_set_bits(struct twlcore *twlcore, u16 reg, u8 mask, u8 val)
+{
+	u8 tmp;
+	int ret;
+
+	ret = twlcore_reg_read(twlcore, reg, &tmp);
+	tmp = (tmp & ~mask) | val;
+
+	if (ret)
+		ret = twlcore_reg_write(twlcore, reg, tmp);
+
+	return ret;
+}
+EXPORT_SYMBOL(twlcore_set_bits);
+
+static ssize_t twl_read(struct cdev *cdev, void *_buf, size_t count,
+		ulong offset, ulong flags)
+{
+	struct twlcore *priv = to_twlcore(cdev);
+	u8 *buf = _buf;
+	size_t i;
+	int ret;
+
+	for (i = 0; i < count; i++) {
+		ret = twlcore_reg_read(priv, offset, buf);
+		if (ret)
+			return (ssize_t)ret;
+		buf++;
+		offset++;
+	}
+
+	return count;
+}
+
+static ssize_t twl_write(struct cdev *cdev, const void *_buf, size_t count,
+		ulong offset, ulong flags)
+{
+	struct twlcore *twlcore = to_twlcore(cdev);
+	const u8 *buf = _buf;
+	size_t i;
+	int ret;
+
+	for (i = 0; i < count; i++) {
+		ret = twlcore_reg_write(twlcore, offset, *buf);
+		if (ret)
+			return (ssize_t)ret;
+		buf++;
+		offset++;
+	}
+
+	return count;
+}
+
+struct file_operations twl_fops = {
+	.lseek	= dev_lseek_default,
+	.read	= twl_read,
+	.write	= twl_write,
+};
+EXPORT_SYMBOL(twl_fops);