Re: [PATCH] iio: pressure: hsc030pa: Fix i2c_transfer return value check

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 29 Jan 2026 17:01:46 +0200
Antoniu Miclaus <antoniu.miclaus@analog.com> wrote:

> The i2c_transfer() function returns the number of messages
> successfully transferred. The function sends 1 message but checks
> for ret == 2, which can never be true. This causes the function to
> always return an error (1) instead of success (0).
> 
> Fix the check to compare against the actual number of messages sent.
> 
> Fixes: 6362d96585e3 ("iio: pressure: driver for Honeywell HSC/SSC series")
> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>

Not a bug with any impact because the check is on ret < 0
at the caller. 

So this commit message needs adjustment to reflect that - little
point in anyone backporting it as a result.

If it were ever other than 1 or zero we'd want to do something subtler and
even though that doesn't happen I'd write the code differently to reflect the different
potential outcomes
> ---
>  drivers/iio/pressure/hsc030pa_i2c.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/pressure/hsc030pa_i2c.c b/drivers/iio/pressure/hsc030pa_i2c.c
> index a34ef4653f34..e780732c7b75 100644
> --- a/drivers/iio/pressure/hsc030pa_i2c.c
> +++ b/drivers/iio/pressure/hsc030pa_i2c.c
> @@ -35,7 +35,7 @@ static int hsc_i2c_recv(struct hsc_data *data)
>  
>  	ret = i2c_transfer(client->adapter, &msg, 1);
>  
> -	return (ret == 2) ? 0 : ret;
> +	return (ret == 1) ? 0 : ret;
That is
	if (ret < 0)
		return ret;

	if (ret != 1)
		return -EIO;

	return 0;

>  }
>  
>  static int hsc_i2c_probe(struct i2c_client *client)