Re: [PATCH v2] dt-bindings: mmc: Set maximum documented operating frequency as 384MHz

[Ulf Hansson]

On Tue, 26 Jul 2022 at 10:45, Bhupesh Sharma <bhupesh.sharma@xxxxxxxxxx> wrote:
>
> As Ulf noted in [1], the maximum operating frequency
> documented in the mmc-controller device-tree bindings
> should be updated to the maximum frequency supported
> by the mmc controller(s).
>
> Without this fix in place, the 'make dtbs_check' reports
> issues with 'max-frequency' value for ipq8074 sdhci node:
>
>   arch/arm64/boot/dts/qcom/ipq8074-hk01.dtb: mmc@7824900:
>    max-frequency:0:0: 384000000 is greater than the maximum of 200000000
>
> [1]. https://www.spinics.net/lists/kernel/msg4442049.html
>
> Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> Cc: Rob Herring <robh@xxxxxxxxxx>
> Signed-off-by: Bhupesh Sharma <bhupesh.sharma@xxxxxxxxxx>

Applied for next, thanks!

Kind regards
Uffe


> ---
>  - v1 can be viewed here: https://lore.kernel.org/linux-arm-msm/20220725180916.2850228-1-bhupesh.sharma@xxxxxxxxxx/
>  - Rebased on linux-next/master
>
>  .../devicetree/bindings/mmc/mmc-controller.yaml     | 13 ++++++++++---
>  1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> index ff5ce89e5111..802e3ca8be4d 100644
> --- a/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> +++ b/Documentation/devicetree/bindings/mmc/mmc-controller.yaml
> @@ -88,11 +88,18 @@ properties:
>      default: 1
>
>    max-frequency:
> -    description:
> -      Maximum operating frequency of the bus.
> +    description: |
> +      Maximum operating frequency of the bus:
> +        - for eMMC, the maximum supported frequency is 200MHz,
> +        - for SD/SDIO cards the SDR104 mode has a max supported
> +          frequency of 208MHz,
> +        - some mmc host controllers do support a max frequency upto
> +          384MHz.
> +      So, lets keep the maximum supported value here.
> +
>      $ref: /schemas/types.yaml#/definitions/uint32
>      minimum: 400000
> -    maximum: 200000000
> +    maximum: 384000000
>
>    disable-wp:
>      $ref: /schemas/types.yaml#/definitions/flag
> --
> 2.35.3
>