[PATCH v5 1/9] dt-bindings: mmc: spacemit,sdhci: add pinctrl support for voltage switching
Krzysztof Kozlowski
krzk at kernel.org
Mon Mar 30 23:48:30 PDT 2026
On Mon, Mar 30, 2026 at 10:38:02AM +0200, Iker Pedrosa wrote:
> Document pinctrl properties to support voltage-dependent pin
> configuration switching for UHS-I SD card modes.
>
> Add optional pinctrl-names property with two states:
> - "default": For 3.3V operation with standard drive strength
> - "state_uhs": For 1.8V operation with optimized drive strength
>
> These pinctrl states allow the SDHCI driver to coordinate voltage
> switching with pin configuration changes, ensuring proper signal
> integrity during UHS-I mode transitions.
>
> Signed-off-by: Iker Pedrosa <ikerpedrosam at gmail.com>
> ---
> .../devicetree/bindings/mmc/spacemit,sdhci.yaml | 17 +++++++++++++++++
> 1 file changed, 17 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> index 9a055d963a7f0cdba4741c1e3e7269688dcd5f45..201ab97f0e88376a4680dcca7917e8b3172bd84a 100644
> --- a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> +++ b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> @@ -44,6 +44,20 @@ properties:
> - const: axi
> - const: sdh
>
> + pinctrl-names:
> + minItems: 1
> + maxItems: 2
> + items:
> + enum:
No, that's not enum but list. Look here:
> + - default
> + - state_uhs
Instead: uhs
> +
> + pinctrl-0:
> + description: Default pinctrl state for 3.3V operation
So first item must be default, not uhs
Best regards,
Krzysztof
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