Moved i2c driver out of cpu/mpc86xx/i2c.c into drivers/fsl_i2c.c

in an effort to begin to unify the umpteen FSL I2C drivers that
are all otherwise very similar.

Signed-off-by: Jon Loeliger <jdl@freescale.com>

1 files changed, 247 insertions, 0 deletions

diff --git a/drivers/fsl_i2c.c b/drivers/fsl_i2c.c
new file mode 100644
index 0000000..72b2556
--- /dev/null
+++ b/drivers/fsl_i2c.c
@@ -0,0 +1,247 @@
+/*
+ * Copyright 2006 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+
+#include <common.h>
+#include <command.h>
+
+#ifdef CONFIG_HARD_I2C
+
+#include <asm/io.h>
+#include <asm/fsl_i2c.h>
+
+#define I2C_TIMEOUT	(CFG_HZ / 4)
+
+#define I2C	((struct fsl_i2c *)(CFG_IMMR + CFG_I2C_OFFSET))
+
+
+void
+i2c_init(int speed, int slaveadd)
+{
+	/* stop I2C controller */
+	writeb(0x0 , &I2C->cr);
+
+	/* set clock */
+	writeb(0x3f, &I2C->fdr);
+
+	/* set default filter */
+	writeb(0x10, &I2C->dfsrr);
+
+	/* write slave address */
+	writeb(slaveadd, &I2C->adr);
+
+	/* clear status register */
+	writeb(0x0, &I2C->sr);
+
+	/* start I2C controller */
+	writeb(I2C_CR_MEN, &I2C->cr);
+}
+
+static __inline__ int
+i2c_wait4bus(void)
+{
+	ulong timeval = get_timer (0);
+
+	while (readb(&I2C->sr) & I2C_SR_MBB) {
+		if (get_timer(timeval) > I2C_TIMEOUT) {
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static __inline__ int
+i2c_wait(int write)
+{
+	u32 csr;
+	ulong timeval = get_timer(0);
+
+	do {
+		csr = readb(&I2C->sr);
+		if (!(csr & I2C_SR_MIF))
+			continue;
+
+		writeb(0x0, &I2C->sr);
+
+		if (csr & I2C_SR_MAL) {
+			debug("i2c_wait: MAL\n");
+			return -1;
+		}
+
+		if (!(csr & I2C_SR_MCF))	{
+			debug("i2c_wait: unfinished\n");
+			return -1;
+		}
+
+		if (write == I2C_WRITE && (csr & I2C_SR_RXAK)) {
+			debug("i2c_wait: No RXACK\n");
+			return -1;
+		}
+
+		return 0;
+	} while (get_timer (timeval) < I2C_TIMEOUT);
+
+	debug("i2c_wait: timed out\n");
+	return -1;
+}
+
+static __inline__ int
+i2c_write_addr (u8 dev, u8 dir, int rsta)
+{
+	writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX
+	       | (rsta ? I2C_CR_RSTA : 0),
+	       &I2C->cr);
+
+	writeb((dev << 1) | dir, &I2C->dr);
+
+	if (i2c_wait(I2C_WRITE) < 0)
+		return 0;
+
+	return 1;
+}
+
+static __inline__ int
+__i2c_write(u8 *data, int length)
+{
+	int i;
+
+	writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX,
+	       &I2C->cr);
+
+	for (i = 0; i < length; i++) {
+		writeb(data[i], &I2C->dr);
+
+		if (i2c_wait(I2C_WRITE) < 0)
+			break;
+	}
+
+	return i;
+}
+
+static __inline__ int
+__i2c_read(u8 *data, int length)
+{
+	int i;
+
+	writeb(I2C_CR_MEN | I2C_CR_MSTA | ((length == 1) ? I2C_CR_TXAK : 0),
+	       &I2C->cr);
+
+	/* dummy read */
+	readb(&I2C->dr);
+
+	for (i = 0; i < length; i++) {
+		if (i2c_wait(I2C_READ) < 0)
+			break;
+
+		/* Generate ack on last next to last byte */
+		if (i == length - 2)
+			writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_TXAK,
+			       &I2C->cr);
+
+		/* Generate stop on last byte */
+		if (i == length - 1)
+			writeb(I2C_CR_MEN | I2C_CR_TXAK, &I2C->cr);
+
+		data[i] = readb(&I2C->dr);
+	}
+
+	return i;
+}
+
+int
+i2c_read(u8 dev, uint addr, int alen, u8 *data, int length)
+{
+	int i = 0;
+	u8 *a = (u8*)&addr;
+
+	if (i2c_wait4bus () < 0)
+		goto exit;
+
+	if (i2c_write_addr(dev, I2C_WRITE, 0) == 0)
+		goto exit;
+
+	if (__i2c_write(&a[4 - alen], alen) != alen)
+		goto exit;
+
+	if (i2c_write_addr(dev, I2C_READ, 1) == 0)
+		goto exit;
+
+	i = __i2c_read(data, length);
+
+ exit:
+	writeb(I2C_CR_MEN, &I2C->cr);
+
+	return !(i == length);
+}
+
+int
+i2c_write(u8 dev, uint addr, int alen, u8 *data, int length)
+{
+	int i = 0;
+	u8 *a = (u8*)&addr;
+
+	if (i2c_wait4bus() < 0)
+		goto exit;
+
+	if (i2c_write_addr(dev, I2C_WRITE, 0) == 0)
+		goto exit;
+
+	if (__i2c_write(&a[4 - alen], alen) != alen)
+		goto exit;
+
+	i = __i2c_write(data, length);
+
+ exit:
+	writeb(I2C_CR_MEN, &I2C->cr);
+
+	return !(i == length);
+}
+
+int
+i2c_probe(uchar chip)
+{
+	int tmp;
+
+	/*
+	 * Try to read the first location of the chip.  The underlying
+	 * driver doesn't appear to support sending just the chip address
+	 * and looking for an <ACK> back.
+	 */
+	udelay(10000);
+
+	return i2c_read(chip, 0, 1, (uchar *)&tmp, 1);
+}
+
+uchar
+i2c_reg_read(uchar i2c_addr, uchar reg)
+{
+	uchar buf[1];
+
+	i2c_read(i2c_addr, reg, 1, buf, 1);
+
+	return buf[0];
+}
+
+void
+i2c_reg_write(uchar i2c_addr, uchar reg, uchar val)
+{
+	i2c_write(i2c_addr, reg, 1, &val, 1);
+}
+
+#endif /* CONFIG_HARD_I2C */