Re: [PATCH v2 2/2] iio: adc: ti-ads1119: Add driver

[Jonathan Cameron]

On Mon, 10 Jun 2024 10:26:29 -0300
João Paulo Gonçalves <jpaulo.silvagoncalves@xxxxxxxxx> wrote:

> Hi Jonathan,
> 
> Thanks for the review!
> 
> > > +
> > > +static int ads1119_validate_gain(struct ads1119_state *st, int scale, int uscale)
> > > +{
> > > +	int gain = 1000000 / ((scale * 1000000) + uscale);
> > > +
> > > +	switch (gain) {
> > > +	case 1:
> > > +	case 4:
> > > +		return gain;  
> > Odd to calculate it if we don't need it
> > 		return MICRO / (scale * MICRO + uscale);
> > use constants as it's easy to drop a 0 in these without anyone noticing.
> >  
> > > +	default:
> > > +		return -EINVAL;
> > > +	}
> > > +}
> > > +  
> 
> Just a minor. I do use the calculated value on write_raw() by storing it as the
> new channel gain and would still need to validate it as scale/uscale comes from
> userspace. Maybe I can just remove the validate_gain function and do the check
> directly on write_raw(). What do you think?

If that's the only caller, sure, move it to write raw.

Jonathan

> 
> Regards,
> João Paulo Gonçalves
>