During i2c read the original pattern was: 1. write i2c slave address 2. wait for transmit complete + clear IIF 3. wait for receive acknowledge 4. wait for IIF interrupt Due to the clear of the I2SR register, the IIF flag was cleared, too. So in step 4 the Interrupt wasn't detected. To fix this problem, we move the clean of IIF before the writing of the slave address. So that it looks this way: 0. clear IIF 1. write i2c slave address 2. wait for transmit complete 3. wait for receive acknowledge 4. wait for IIF interrupt Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- drivers/i2c/i2c-imx.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/i2c-imx.c b/drivers/i2c/i2c-imx.c index 387c598..14d5260 100644 --- a/drivers/i2c/i2c-imx.c +++ b/drivers/i2c/i2c-imx.c @@ -177,8 +177,6 @@ static int i2c_imx_trx_complete(struct i2c_adapter *adapter) dev_err(adapter->dev, "<%s> TXR timeout\n", __func__); return -EIO; } - - writeb(0x0, base + IMX_I2C_I2SR); } return 0; @@ -360,6 +358,9 @@ static int i2c_imx_read(struct i2c_adapter *adapter, struct i2c_msg *msgs) "<%s> write slave address: addr=0x%02x\n", __func__, (msgs->addr << 1) | 0x01); + /* clear IIF */ + writeb(0x0, base + IMX_I2C_I2SR); + /* write slave address */ writeb((msgs->addr << 1) | 0x01, base + IMX_I2C_I2DR); -- 1.6.5.4 _______________________________________________ u-boot-v2 mailing list u-boot-v2@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/u-boot-v2
