[PATCH 2/2] arm64: dts: rockchip: Enable SDIO Wi-Fi on NanoPi R2S Plus

[Deomid "rojer" Ryabkov]

Hi Shawn,

agreed, it makes no sense here. will drop in v2, holding on for
feedback on patch 1.

On Tue, 27 Oct 2026 at 15:58, Shawn Lin <shawn.lin at rock-chips.com> wrote:
>
> Hi Deomid
>
> 在 2026/10/24 星期六 7:59, Deomid rojer Ryabkov 写道:
> > The NanoPi R2S Plus has an M.2 E-key slot wired to the sdmmc_ext
> > controller in 4-bit SDIO mode, where FriendlyElec fit an optional
> > Fn-Link 6222B-SRC (Realtek RTL8822CS) module:
> >
> >    - SDIO signalling at a fixed 1.8V (VCC_18)
> >    - WIFI_REG_ON on GPIO3_B0, 32kHz sleep clock from the RK805 CLKOUT2
> >
> > Enable the controller and add the power sequence. The SDIO pins need
> > 8mA drive strength for SDR104 tuning to succeed, as in the vendor
> > device tree [1]; with the SoC default of 4mA no sample phase works.
> >
> > On boards without the module the controller gives up after about 0.2s
> > ("mmc2: Failed to initialize a non-removable card"); nothing else is
> > affected.
> >
> > With the mmc core change for the module's CMD11 handling at a fixed
> > 1.8V [2], the module is tuned to SDR104 at 150 MHz and works with the
> > rtw88_8822cs driver; without it, it runs in high-speed mode at 50 MHz.
> >
> > [1] https://github.com/friendlyarm/kernel-rockchip/blob/9238df9d21e835bba35c8ba5248784387936cb2e/arch/arm64/boot/dts/rockchip/rk3328-nanopi-r2-rev24.dts#L144-L172
> > [2] https://lore.kernel.org/linux-mmc/20261023232813.2983368-1-rojer@rojer.me/
> > Signed-off-by: Deomid rojer Ryabkov <rojer at rojer.me>
> > ---
> >   .../dts/rockchip/rk3328-nanopi-r2s-plus.dts   | 56 +++++++++++++++++++
> >   1 file changed, 56 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/rockchip/rk3328-nanopi-r2s-plus.dts b/arch/arm64/boot/dts/rockchip/rk3328-nanopi-r2s-plus.dts
> > index 6ba4a74cb1f..db19a18ae45 100644
> > --- a/arch/arm64/boot/dts/rockchip/rk3328-nanopi-r2s-plus.dts
> > +++ b/arch/arm64/boot/dts/rockchip/rk3328-nanopi-r2s-plus.dts
> > @@ -17,6 +17,15 @@ / {
> >       aliases {
> >               mmc1 = &emmc;
> >       };
> > +
> > +     sdio_pwrseq: sdio-pwrseq {
> > +             compatible = "mmc-pwrseq-simple";
> > +             clocks = <&rk805 1>;
> > +             clock-names = "ext_clock";
> > +             pinctrl-names = "default";
> > +             pinctrl-0 = <&wifi_reg_on_h>;
> > +             reset-gpios = <&gpio3 RK_PB0 GPIO_ACTIVE_LOW>;
> > +     };
> >   };
> >
> >   &emmc {
> > @@ -34,3 +43,50 @@ &io_domains {
> >       vccio4-supply = <&vcc_io_33>;
> >       vccio6-supply = <&vcc_18>;
> >   };
> > +
> > +&pinctrl {
> > +     wifi {
> > +             wifi_reg_on_h: wifi-reg-on-h {
> > +                     rockchip,pins = <3 RK_PB0 RK_FUNC_GPIO &pcfg_pull_none>;
> > +             };
> > +     };
> > +};
> > +
> > +/*
> > + * SDR104 tuning fails with the default 4mA drive strength, use 8mA like the
> > + * vendor device tree.
> > + */
> > +&sdmmc0ext_bus4 {
> > +     rockchip,pins =
> > +             <3 RK_PA4 3 &pcfg_pull_up_8ma>,
> > +             <3 RK_PA5 3 &pcfg_pull_up_8ma>,
> > +             <3 RK_PA6 3 &pcfg_pull_up_8ma>,
> > +             <3 RK_PA7 3 &pcfg_pull_up_8ma>;
> > +};
> > +
> > +&sdmmc0ext_clk {
> > +     rockchip,pins = <3 RK_PA2 3 &pcfg_pull_none_8ma>;
> > +};
> > +
> > +&sdmmc0ext_cmd {
> > +     rockchip,pins = <3 RK_PA0 3 &pcfg_pull_up_8ma>;
> > +};
> > +
> > +/* Optional M.2 E-key SDIO Wi-Fi module (Fn-Link 6222B-SRC, RTL8822CS) */
> > +&sdmmc_ext {
> > +     bus-width = <4>;
> > +     cap-sd-highspeed;
> > +     cap-sdio-irq;
> > +     disable-wp;
>
> Drop disable-wp.
>
> Otherwise,
>
> Reviewed-by: Shawn Lin <shawn.lin at rock-chips.com>
>
> > +     keep-power-in-suspend;
> > +     mmc-pwrseq = <&sdio_pwrseq>;
> > +     no-mmc;
> > +     no-sd;
> > +     non-removable;
> > +     pinctrl-names = "default";
> > +     pinctrl-0 = <&sdmmc0ext_clk &sdmmc0ext_cmd &sdmmc0ext_bus4>;
> > +     sd-uhs-sdr104;
> > +     vmmc-supply = <&vcc_io_33>;
> > +     vqmmc-supply = <&vcc_18>;
> > +     status = "okay";
> > +};
>


-- 
Deomid "rojer" Ryabkov
rojer at rojer.me