In case we receive NACK on DATA we shouldn't be resetting the controller, rather we should issue STOP command. This will terminate the current transaction and -EIO is returned. While at that handle the SMBus Quick Command properly. We shouldn't be setting the XLP9XX_I2C_CMD_READ/WRITE for such transactions. Signed-off-by: George Cherian <george.cherian@xxxxxxxxxx> --- drivers/i2c/busses/i2c-xlp9xx.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-xlp9xx.c b/drivers/i2c/busses/i2c-xlp9xx.c index 42dd1fa..eb8913e 100644 --- a/drivers/i2c/busses/i2c-xlp9xx.c +++ b/drivers/i2c/busses/i2c-xlp9xx.c @@ -352,7 +352,9 @@ static int xlp9xx_i2c_xfer_msg(struct xlp9xx_i2c_dev *priv, struct i2c_msg *msg, /* set cmd reg */ cmd = XLP9XX_I2C_CMD_START; - cmd |= (priv->msg_read ? XLP9XX_I2C_CMD_READ : XLP9XX_I2C_CMD_WRITE); + if (msg->len) + cmd |= (priv->msg_read ? + XLP9XX_I2C_CMD_READ : XLP9XX_I2C_CMD_WRITE); if (last_msg) cmd |= XLP9XX_I2C_CMD_STOP; @@ -361,12 +363,12 @@ static int xlp9xx_i2c_xfer_msg(struct xlp9xx_i2c_dev *priv, struct i2c_msg *msg, timeleft = msecs_to_jiffies(XLP9XX_I2C_TIMEOUT_MS); timeleft = wait_for_completion_timeout(&priv->msg_complete, timeleft); - if (priv->msg_err) { + if (priv->msg_err & XLP9XX_I2C_INTEN_BUSERR) { dev_dbg(priv->dev, "transfer error %x!\n", priv->msg_err); - if (priv->msg_err & XLP9XX_I2C_INTEN_BUSERR) - xlp9xx_i2c_init(priv); - return (priv->msg_err & XLP9XX_I2C_INTEN_NACKADDR) ? - -ENXIO : -EIO; + xlp9xx_write_i2c_reg(priv, XLP9XX_I2C_CMD, XLP9XX_I2C_CMD_STOP); + return -EIO; + } else if (priv->msg_err & XLP9XX_I2C_INTEN_NACKADDR) { + return -ENXIO; } if (timeleft == 0) { -- 2.1.4