Re: [PATCH] pinctrl: mediatek: Fix fallback behavior for bias_set_combo

[Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>]

On Thu, Jul 1, 2021 at 3:21 PM Chen-Yu Tsai <wenst@xxxxxxxxxxxx> wrote:
>
> On Thu, Jul 1, 2021 at 2:55 PM Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx> wrote:
> >
> > Some pin doesn't support PUPD register, if it fails and fallbacks with
> > bias_set_combo case, it will call mtk_pinconf_bias_set_pupd_r1_r0() to
> > modify the PUPD pin again.
> >
> > Since the general bias set are either PU/PD or PULLSEL/PULLEN, try
> > bias_set or bias_set_rev1 for this fallback case.
> >
> > Fixes: 81bd1579b43e ("pinctrl: mediatek: Fix fallback call path")
> > Signed-off-by: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx>
> > ---
> >  drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c | 9 ++++++---
> >  1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> > index 5b3b048725cc8..0cdff487836fa 100644
> > --- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> > +++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> > @@ -926,9 +926,12 @@ int mtk_pinconf_adv_pull_set(struct mtk_pinctrl *hw,
> >                         if (err)
> >                                 return err;
> >                 } else if (hw->soc->bias_set_combo) {
> > -                       err = hw->soc->bias_set_combo(hw, desc, pullup, arg);
> > -                       if (err)
> > -                               return err;
> > +                       err = mtk_pinconf_bias_set_rev1(hw, desc, pullup);
> > +                       if (err) {
> > +                               err = mtk_pinconf_bias_set(hw, desc, pullup);
> > +                               if (err)
> > +                                       return err;
>
> You don't need to nest this. If mtk_pinconf_bias_set_rev1() succeeds,
> err would be 0 and the following if blocks would all be skipped. So:
>
> err = mtk_pinconf_bias_set_rev1();
> if (err)
>         err = mtk_pinconf_bias_set();
> if (err)
>         return err;
>
> Moreover, maybe you should rework the test for hw->soc->bias_set_combo,
> as it is no longer relevant to the code within the if block?
>

Thanks for the comments. It's addressed in v2.

We can try PU/PD and PULLSEL/PULLEN even for pins that don't support
them (eg. mt6797). They will return -ENOTSUPP in
mtk_hw_pin_field_lookup() so won't break current testing logic.

>
> ChenYu
>
> > +                       }
> >                 } else {
> >                         return -ENOTSUPP;
> >                 }
> > --
> > 2.32.0.93.g670b81a890-goog
> >
> >
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