Re: [PATCH 3/3] iio: addac: ad74413r: correct comparator gpio getters mask usage

[Andy Shevchenko]

On Mon, Jan 10, 2022 at 6:55 PM Cosmin Tanislav <demonsingur@xxxxxxxxx> wrote:
> On 1/9/22 14:13, Andy Shevchenko wrote:
> > On Fri, Jan 7, 2022 at 7:34 AM Cosmin Tanislav <demonsingur@xxxxxxxxx> wrote:

...

> >> -       status &= AD74413R_DIN_COMP_OUT_SHIFT_X(real_offset);
> >> +       status &= BIT(real_offset);
> >
> > But this is completely different.
>
> What do you mean by this is completely different?
>
> It was broken before, it is fixed now. Indeed, I'm missing
> the Fixes tag, if that's what you meant.

Yeah, I explained myself below. I think you got the idea.

...

> >> +       bitmap_zero(bits, chip->ngpio);
> >> +
> >>          for_each_set_bit(offset, mask, chip->ngpio) {
> >>                  unsigned int real_offset = st->comp_gpio_offsets[offset];
> >>
> >>                  if (val & BIT(real_offset))
> >> -                       *bits |= offset;
> >> +                       *bits |= BIT(offset);
> >
> > So, how was it working before? If it fixes, it should go with the
> > Fixes tag and before patch 2.
> >
> > On top of that, you may try to see if one of bitmap_*() APIs can be
> > suitable here to perform the above in a more optimal way.
> > (At least this conditional can be replaced with __asign_bit() call,
> > but I think refactoring the entire loop may reveal a better approach)
>
> I can replace the if and bitmap_zero with __assign_bit, as you
> suggested. I'm not familiar with bitmap APIs, do you have a suggestion?

For now I'm lacking any new suggestions. If you don't see any better
approaches, let's go with __assign_bit().

-- 
With Best Regards,
Andy Shevchenko