[PATCH 2/2] arm64: dts: mediatek: mt8188-geralt: enable Wi-Fi card

[Chen-Yu Tsai]

On Wed, May 6, 2026 at 10:14 PM Icenowy Zheng <zhengxingda at iscas.ac.cn> wrote:
>
> 在 2026-05-04一的 15:34 +0800，Chen-Yu Tsai写道：
> > Hi,
> >
> > On Mon, May 4, 2026 at 3:28 PM Icenowy Zheng
> > <zhengxingda at iscas.ac.cn> wrote:
> > >
> > > The mainline pcie-mediatek-gen3 driver does not have code managing
> > > downstream device power / reset.
> > >
> > > As the Wi-Fi card on ciri is a fixed device, set the related
> > > regulator
> > > to always-on and use GPIO hog to set the status of its reset pin.
> >
> > The plan now is to model it as an M.2 E-key slot (even though the
> > chip
> > is actually soldered on the main board).
>
> Interestingly I saw a "PCI_PWRCTRL_GENERIC" driver in 7.1, although it
> does not support toggling #PERST now -- maybe this should be done and
> used instead? (Well it looks like the driver had existed for some time,
> but it was for "slots" previously)

#PERST currently is still left to the PCI controller drivers, since some
of them have dedicated functions for it, while others use the GPIO API.

If you check the history of the "PCI pwrctrl framework" [1], you will
see the design choice.

[1] https://lore.kernel.org/all/20260115-pci-pwrctrl-rework-v5-0-9d26da3ce903@oss.qualcomm.com/

> Thanks,
> Icenowy
>
> >
> > I have some of the patches ready, but I'm still working out the USB
> > side of it.
> >
> >
> > ChenYu
> >
> > > Signed-off-by: Icenowy Zheng <zhengxingda at iscas.ac.cn>
> > > ---
> > >  arch/arm64/boot/dts/mediatek/mt8188-geralt.dtsi | 11 +++++++++++
> > >  1 file changed, 11 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/mediatek/mt8188-geralt.dtsi
> > > b/arch/arm64/boot/dts/mediatek/mt8188-geralt.dtsi
> > > index 8e423504ec052..c25780098103b 100644
> > > --- a/arch/arm64/boot/dts/mediatek/mt8188-geralt.dtsi
> > > +++ b/arch/arm64/boot/dts/mediatek/mt8188-geralt.dtsi
> > > @@ -544,6 +544,11 @@ &mt6359codec {
> > >         mediatek,mic-type-2 = <2>; /* DMIC */
> > >  };
> > >
> > > +&mt6359_vcn18_ldo_reg {
> > > +       /* Used by WLAN */
> > > +       regulator-always-on;
> > > +};
> > > +
> > >  &mt6359_vcore_buck_reg {
> > >         regulator-always-on;
> > >  };
> > > @@ -1145,6 +1150,12 @@ pins-en-pp3300-wlan {
> > >                         output-low;
> > >                 };
> > >         };
> > > +
> > > +       wlan-reset-hog {
> > > +               gpio-hog;
> > > +               gpios = <145 GPIO_ACTIVE_HIGH>;
> > > +               output-high;
> > > +       };
> > >  };
> > >
> > >  &pmic {
> > > --
> > > 2.52.0
> > >
> > >
>