[U-Boot] [PATCH 13/24] mxc_i2c: check for arbitration lost

Troy Kisky
2012-06-22T04:12:08Z

No need to continue waiting if arbitration lost.

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
---
drivers/i2c/mxc_i2c.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
index 2bff2b8..df033ea 100644
--- a/drivers/i2c/mxc_i2c.c
+++ b/drivers/i2c/mxc_i2c.c
@@ -54,6 +54,7 @@ struct mxc_i2c_regs {

#define I2SR_ICF (1 << 7)
#define I2SR_IBB (1 << 5)
+#define I2SR_IAL (1 << 4)
#define I2SR_IIF (1 << 1)
#define I2SR_RX_NO_AK (1 << 0)

@@ -164,6 +165,12 @@ static unsigned wait_for_sr_state(struct mxc_i2c_regs *i2c_regs, unsigned state)
ulong start_time = get_timer(0);
for (;;) {
sr = readb(&i2c_regs->i2sr);
+ if (sr & I2SR_IAL) {
+ writeb(sr & ~I2SR_IAL, &i2c_regs->i2sr);
+ printf("%s: Arbitration lost sr=%x cr=%x state=%x\n",
+ __func__, sr, readb(&i2c_regs->i2cr), state);
+ return -ERESTART;
+ }
if ((sr & (state >> 8)) == (unsigned char)state)
return sr;
elapsed = get_timer(start_time);
--
1.7.9.5