Re: [PATCH v2 1/5] iio: chemical: sgp40: Do not convert I2C errors to EIO

[Joshua Crofts]

On Mon, 2 Nov 2026 11:12:54 +0200
Jaakko Koivisto <jmatko@xxxxxx> wrote:

> Any negative error returned by i2c_master_send() in
> sgp40_measure_resistance_raw() was caught by the
> branch guarding against short sends, and the error
> was subsequently replaced with -EIO.

Please wrap the commit message to ~75 characters per line next
time. Otherwise LGTM.

Reviewed-by: Joshua Crofts <crofts@xxxxxxxxxx>

> Check for any negative errors first and propagate
> the error without conversion.
> 
> Fixes: 1081b9d97152 ("iio: chemical: Add driver support for sgp40")
>

Also, no blank lines in the tag block.

> Signed-off-by: Jaakko Koivisto <jmatko@xxxxxx>
> ---
> Tested by forcing i2c clock to ground. The resulting ETIMEDOUT and
> EREMOTEIO are now correctly communicated to userspace instead of
> converting to EIO.
> 
>  drivers/iio/chemical/sgp40.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/iio/chemical/sgp40.c b/drivers/iio/chemical/sgp40.c
> index b2b5e32a9eb2..3a239fb6847f 100644
> --- a/drivers/iio/chemical/sgp40.c
> +++ b/drivers/iio/chemical/sgp40.c
> @@ -187,6 +187,8 @@ static int sgp40_measure_resistance_raw(struct sgp40_data *data, u16 *resistance
>  	mutex_unlock(&data->lock);
>  
>  	ret = i2c_master_send(client, (const char *)&tg, sizeof(tg));
> +	if (ret < 0)
> +		return ret;
>  	if (ret != sizeof(tg)) {
>  		dev_warn(data->dev, "i2c_master_send ret: %d sizeof: %zu\n", ret, sizeof(tg));
>  		return -EIO;



-- 
Kind regards,
Joshua Crofts