Re: [PATCH V3 2/4] dt-bindings: mmc: controller: Add max-sd-hs-frequency property
From: Krzysztof Kozlowski
Date: Wed Jun 18 2025 - 03:43:37 EST
On 18/06/2025 09:28, Sarthak Garg wrote:
> Introduce a new optional device tree property `max-sd-hs-frequency` to
> limit the maximum frequency (in Hz) used for SD cards operating in
> High-Speed (HS) mode.
>
> This property is useful for platforms with vendor-specific hardware
> constraints, such as the presence of a level shifter that cannot
> reliably support the default 50 MHz HS frequency. It allows the host
> driver to cap the HS mode frequency accordingly.
>
> Signed-off-by: Sarthak Garg <quic_sartgarg@xxxxxxxxxxx>
> ---
> .../devicetree/bindings/mmc/mmc-controller-common.yaml | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml b/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml
> index 9a7235439759..1976f5f8c401 100644
> --- a/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml
> +++ b/Documentation/devicetree/bindings/mmc/mmc-controller-common.yaml
> @@ -93,6 +93,16 @@ properties:
> minimum: 400000
> maximum: 384000000
>
> + max-sd-hs-frequency:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: |
> + Maximum frequency (in Hz) to be used for SD cards operating in
> + High-Speed (HS) mode. This is useful for platforms with vendor-specific
> + limitations, such as the presence of a level shifter that cannot support
> + the default 50 MHz HS frequency or other.
> + minimum: 400000
> + maximum: 50000000
This might be fine, but your DTS suggests clearly this is SoC compatible
deducible, which I already said at v1.
So now you send v3 which is the same as v1, so you get the same comments.
Best regards,
Krzysztof