Re: [PATCH 1/2] dt-bindings: mmc: renesas,sdhi: Add mux-states property

From: Krzysztof Kozlowski

Date: Sun Nov 30 2025 - 03:22:45 EST


On 28/11/2025 17:15, Josua Mayer wrote:
> Add mux controller support for when sdio lines are muxed between a host
> and multiple cards.
>
> There are several devices supporting a choice of eMMC or SD on a single
> board by both dip switch and gpio, e.g. Renesas RZ/G2L SMARC SoM and
> SolidRun RZ/G2L SoM.
>
> In-tree dts for the Renesas boards currently rely on preprocessor macros
> to hog gpios and define the card.
>
> By adding mux-states property to sdio controller description, boards can
> correctly describe the mux that already exists in hardware - and drivers
> can coordinate between mux selection and probing for cards.
>
> Signed-off-by: Josua Mayer <josua@xxxxxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml b/Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml
> index c754ea71f51f7..55635c60ad73a 100644
> --- a/Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml
> +++ b/Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml
> @@ -106,6 +106,11 @@ properties:
> iommus:
> maxItems: 1
>
> + mux-states:
> + description:
> + mux controller node to route the SDIO signals from SoC to cards.
> + maxItems: 1
> +
> power-domains:
> maxItems: 1
>
> @@ -262,9 +267,17 @@ unevaluatedProperties: false
> examples:
> - |
> #include <dt-bindings/clock/r8a7790-cpg-mssr.h>
> + #include <dt-bindings/gpio/gpio.h>
> #include <dt-bindings/interrupt-controller/arm-gic.h>
> + #include <dt-bindings/pinctrl/rzg2l-pinctrl.h>
> #include <dt-bindings/power/r8a7790-sysc.h>
>
> + mux: mux-controller {
> + compatible = "gpio-mux";
> + #mux-state-cells = <1>;
> + mux-gpios = <&pinctrl RZG2L_GPIO(22, 1) GPIO_ACTIVE_LOW>;


Wrong indentation and not really relevant here, so just drop.

Best regards,
Krzysztof