Re: [PATCH 1/4] dt-bindings: mmc: spacemit-sdhci: Add clock-frequency property

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] Introduction of a redundant custom clock configuration property, bypassing standard Device Tree mechanisms.
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commit 1745887406b566692891c256f7b9ab7126926f90
Author: Long Wan <long.wan@linux.spacemit.com>

dt-bindings: mmc: spacemit-sdhci: Add clock-frequency property

This commit introduces a custom clock-frequency property to the
spacemit-sdhci device tree binding. The property is intended to define the
initial rate of the IO clock based on board layout validation.

> diff --git a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> index 34d202af909f2..f35bf7ce08dd8 100644
> --- a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> +++ b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
> @@ -29,6 +29,13 @@ properties:
>        - description: core clock, used by internal controller
>        - description: io clock, output for SD, SDIO, eMMC device
>  
> +  clock-frequency:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      Rate of the io clock in Hz. When present the io clock is programmed to
> +      this rate, allowing a board to select the rate its layout was validated
> +      at.

[Severity: Medium]
Does this property reinvent standard clock configuration mechanisms?

In modern Device Tree design, setting the initial rate of a clock provider
consumed by a device is typically achieved using the standard assigned-clocks
and assigned-clock-rates properties, which the core clock framework processes
automatically.

Alternatively, if the goal is to cap the bus frequency for signal integrity,
the standard MMC max-frequency property should be used. Repurposing
clock-frequency to manually parse and call clk_set_rate() creates a
non-standard ABI for clock configuration and duplicates core functionality.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260902-07-k3-sdhci-dts-v1-0-4e7909cf4233@kernel.org?part=1