[PATCH 2/4] dt-bindings: mmc: spacemit,sdhci: Add tx delay property

Krzysztof Kozlowski krzk at kernel.org
Thu Sep 3 06:00:39 PDT 2026


On Wed, Sep 02, 2026 at 07:03:13AM +0000, Yixun Lan wrote:
> From: Long Wan <long.wan at linux.spacemit.com>
> 
> Introduce a vendor specific property to configure the step count of TX
> delay line which should be applied before RX tuning, compensating for
> board level trace differences. The TX delay line result comes from test
> out of real board which vary from different hardware layout.
> 
> Signed-off-by: Long Wan <long.wan at linux.spacemit.com>
> Signed-off-by: Yixun Lan <dlan at kernel.org>
> ---
>  Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> index f35bf7ce08dd..3399a2d076dc 100644
> --- a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> +++ b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> @@ -63,6 +63,16 @@ properties:
>    pinctrl-1:
>      description: Optional pinctrl state for 1.8V UHS operation with "uhs" name
>  
> +  spacemit,tx-delay:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    minimum: 0
> +    maximum: 255

default: 0, I guess?

Best regards,
Krzysztof




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