Re: [PATCH v2 4/8] iio: inkern: return valid type on raw to processed conversion

["Liam Beguin" <liambeguin@gmail.com>]

On Wed Jun 9, 2021 at 4:32 PM EDT, Jonathan Cameron wrote:
> On Mon, 7 Jun 2021 10:47:14 -0400
> Liam Beguin <liambeguin@gmail.com> wrote:
>
> > From: Liam Beguin <lvb@xiphos.com>
> > 
> > iio_convert_raw_to_processed_unlocked() applies the offset and scale of
> > a channel on it's raw value.
> > The processed value returned is always an integer. Return IIO_VAL_INT so
> > that consumers can use this return value directly.
> > 
> > Signed-off-by: Liam Beguin <lvb@xiphos.com>
> This looks likely to cause breakage given that return value will go to
> consumers directly via iio_convert_raw_to_processed()
>
> Looks like this will break lmp91000 which checks for error as
>
> if (ret)
>

IIO_VAL_INT seems like a better return value here since the consumer
gets an integer. I can look at existing consumers and patch those too.
Or would you rather I drop this patch?

> > ---
> >  drivers/iio/inkern.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
> > index 0b5667f22b1d..00d234e87234 100644
> > --- a/drivers/iio/inkern.c
> > +++ b/drivers/iio/inkern.c
> > @@ -618,7 +618,7 @@ static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
> >  		 * raw value and return.
> >  		 */
> >  		*processed = raw * scale;
> > -		return 0;
> > +		return IIO_VAL_INT;
> >  	}
> >  
> >  	switch (scale_type) {
> > @@ -652,7 +652,7 @@ static int iio_convert_raw_to_processed_unlocked(struct iio_channel *chan,
> >  		return -EINVAL;
> >  	}
> >  
> > -	return 0;
> > +	return IIO_VAL_INT;
> >  }
> >  
> >  int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,