[U-Boot] [PATCH 03/24] mxc_i2c: create tx_byte function

Troy Kisky
2012-06-22T04:11:58Z

Use tx_byte function instead of having 3 copies
of the code.

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
---
drivers/i2c/mxc_i2c.c | 72 +++++++++++++++----------------------------------
1 file changed, 21 insertions(+), 51 deletions(-)

diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
index 0b46c9c..0fd508a 100644
--- a/drivers/i2c/mxc_i2c.c
+++ b/drivers/i2c/mxc_i2c.c
@@ -33,6 +33,7 @@
#include <common.h>
#include <asm/arch/clock.h>
#include <asm/arch/imx-regs.h>
+#include <asm/errno.h>
#include <asm/io.h>
#include <i2c.h>

@@ -207,17 +208,21 @@ int i2c_imx_trx_complete(void)
udelay(1);
}

- return 1;
+ return -ETIMEDOUT;
}

-/*
- * Check if the transaction was ACKed
- */
-int i2c_imx_acked(void)
+static int tx_byte(struct mxc_i2c_regs *i2c_regs, u8 byte)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
+ unsigned ret;

- return readb(&i2c_regs->i2sr) & I2SR_RX_NO_AK;
+ writeb(byte, &i2c_regs->i2dr);
+ ret = i2c_imx_trx_complete();
+ if (ret < 0)
+ return ret;
+ ret = readb(&i2c_regs->i2sr);
+ if (ret & I2SR_RX_NO_AK)
+ return -ENODEV;
+ return 0;
}

/*
@@ -271,30 +276,6 @@ void i2c_imx_stop(void)
}

/*
- * Set chip address and access mode
- *
- * read = 1: READ access
- * read = 0: WRITE access
- */
-int i2c_imx_set_chip_addr(uchar chip, int read)
-{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
- int ret;
-
- writeb((chip << 1) | read, &i2c_regs->i2dr);
-
- ret = i2c_imx_trx_complete();
- if (ret)
- return ret;
-
- ret = i2c_imx_acked();
- if (ret)
- return ret;
-
- return ret;
-}
-
-/*
* Write register address
*/
int i2c_imx_set_reg_addr(uint addr, int alen)
@@ -303,14 +284,8 @@ int i2c_imx_set_reg_addr(uint addr, int alen)
int ret = 0;

while (alen--) {
- writeb((addr >> (alen * 8)) & 0xff, &i2c_regs->i2dr);
-
- ret = i2c_imx_trx_complete();
- if (ret)
- break;
-
- ret = i2c_imx_acked();
- if (ret)
+ ret = tx_byte(i2c_regs, (addr >> (alen * 8)) & 0xff);
+ if (ret < 0)
break;
}

@@ -322,13 +297,14 @@ int i2c_imx_set_reg_addr(uint addr, int alen)
*/
int i2c_probe(uchar chip)
{
+ struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
int ret;

ret = i2c_imx_start();
if (ret)
return ret;

- ret = i2c_imx_set_chip_addr(chip, 0);
+ ret = tx_byte(i2c_regs, chip << 1);
if (ret)
return ret;

@@ -352,7 +328,7 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
return ret;

/* write slave address */
- ret = i2c_imx_set_chip_addr(chip, 0);
+ ret = tx_byte(i2c_regs, chip << 1);
if (ret)
return ret;

@@ -364,7 +340,7 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
temp |= I2CR_RSTA;
writeb(temp, &i2c_regs->i2cr);

- ret = i2c_imx_set_chip_addr(chip, 1);
+ ret = tx_byte(i2c_regs, (chip << 1) | 1);
if (ret)
return ret;

@@ -419,7 +395,7 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
return ret;

/* write slave address */
- ret = i2c_imx_set_chip_addr(chip, 0);
+ ret = tx_byte(i2c_regs, chip << 1);
if (ret)
return ret;

@@ -428,14 +404,8 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
return ret;

for (i = 0; i < len; i++) {
- writeb(buf[i], &i2c_regs->i2dr);
-
- ret = i2c_imx_trx_complete();
- if (ret)
- return ret;
-
- ret = i2c_imx_acked();
- if (ret)
+ ret = tx_byte(i2c_regs, buf[i]);
+ if (ret < 0)
return ret;
}

--
1.7.9.5