Re: [PATCH v2] i2c: xiic: improve error message when transfer fails to start

[Michal Simek <michal.simek@xxxxxxx>]

On 5/13/24 18:03, marc.ferland@xxxxxxxxx wrote:
> From: Marc Ferland <marc.ferland@xxxxxxxxxxxx>
>
> xiic_start_xfer can fail for different reasons:
>
> - EBUSY: bus is busy or i2c messages still in tx_msg or rx_msg
> - ETIMEDOUT: timed-out trying to clear the RX fifo
> - EINVAL: wrong clock settings
>
> Both EINVAL and ETIMEDOUT will currently print a specific error
> message followed by a generic one, for example:
>
>      Failed to clear rx fifo
>      Error xiic_start_xfer
>
> however EBUSY will simply output the generic message:
>
>      Error xiic_start_xfer
>
> which is not really helpful.
>
> This commit adds a new error message when a busy condition is detected
> and also removes the generic message since it does not provide any
> relevant information to the user.
>
> Signed-off-by: Marc Ferland <marc.ferland@xxxxxxxxxxxx>
> ---
> Changes in v2:
>   - add a message where the error actually occurs (suggested by
>     Andi Shyti)
>   - remove the generic message completely (Andi Shyti)
>
>   drivers/i2c/busses/i2c-xiic.c | 9 +++++----
>   1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c
> index b9ad935d7ff3..afb242be456d 100644
> --- a/drivers/i2c/busses/i2c-xiic.c
> +++ b/drivers/i2c/busses/i2c-xiic.c
> @@ -1114,8 +1114,11 @@ static int xiic_start_xfer(struct xiic_i2c *i2c, struct i2c_msg *msgs, int num)
>   	mutex_lock(&i2c->lock);
>   
>   	ret = xiic_busy(i2c);
> -	if (ret)
> +	if (ret) {
> +		dev_err(i2c->adap.dev.parent,
> +			"cannot start a transfer while busy\n");
>   		goto out;
> +	}
>   
>   	i2c->tx_msg = msgs;
>   	i2c->rx_msg = NULL;
> @@ -1173,10 +1176,8 @@ static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
>   		return err;
>   
>   	err = xiic_start_xfer(i2c, msgs, num);
> -	if (err < 0) {
> -		dev_err(adap->dev.parent, "Error xiic_start_xfer\n");
> +	if (err < 0)
>   		goto out;
> -	}
>   
>   	err = wait_for_completion_timeout(&i2c->completion, XIIC_XFER_TIMEOUT);
>   	mutex_lock(&i2c->lock);


Acked-by: Michal Simek <michal.simek@xxxxxxx>

Thanks,
Michal