[U-Boot] [PATCH 04/24] mxc_i2c: clear i2sr before waiting for bit

Troy Kisky troy.kisky at boundarydevices.com
Fri Jun 22 06:11:59 CEST 2012


Let's clear the sr register before waiting for
bit to be set, instead of clearing it after
hardware sets it. No real operational difference here,
but allows combining of i2c_imx_trx_complete and
i2c_imx_bus_busy in later patches.

Signed-off-by: Troy Kisky <troy.kisky at boundarydevices.com>
---
 drivers/i2c/mxc_i2c.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
index 0fd508a..bae9335 100644
--- a/drivers/i2c/mxc_i2c.c
+++ b/drivers/i2c/mxc_i2c.c
@@ -200,10 +200,8 @@ int i2c_imx_trx_complete(void)
 	int timeout = I2C_MAX_TIMEOUT;
 
 	while (timeout--) {
-		if (readb(&i2c_regs->i2sr) & I2SR_IIF) {
-			writeb(0, &i2c_regs->i2sr);
+		if (readb(&i2c_regs->i2sr) & I2SR_IIF)
 			return 0;
-		}
 
 		udelay(1);
 	}
@@ -215,6 +213,7 @@ static int tx_byte(struct mxc_i2c_regs *i2c_regs, u8 byte)
 {
 	unsigned ret;
 
+	writeb(0, &i2c_regs->i2sr);
 	writeb(byte, &i2c_regs->i2dr);
 	ret = i2c_imx_trx_complete();
 	if (ret < 0)
-- 
1.7.9.5



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