Re: [PATCH] Revert "dt-bindings: usb: mtk-xhci: Make all clocks required"

[Chunfeng Yun]

On Fri, 2022-07-08 at 15:26 -0400, Nícolas F. R. A. Prado wrote:
> This reverts commit ebc4969ae125e65fdb563f66f4bfa7aec95f7eb4. That
> commit was supposed to make the binding better reflect the MediaTek
> XHCI
> hardware block by requiring all clocks to be present. But doing that
> also causes too much noise in the devicetrees, since it requires
> updating old MediaTek DTs to add clock handles for the fixed clocks,
> and
> going forward every new clock added to the binding would require even
> more updates.
> 
> The commit also didn't update the example to match the changes,
> causing
> additional warnings.
> 
> Instead let's keep the clocks optional so that old devicetrees can
> keep
> omitting the fixed clocks, and we'll just add the clocks as required
> on
> new DTs.
> 
> Signed-off-by: Nícolas F. R. A. Prado <nfraprado@xxxxxxxxxxxxx>
> 
> ---
> 
>  Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml | 4
> +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/usb/mediatek,mtk-
> xhci.yaml b/Documentation/devicetree/bindings/usb/mediatek,mtk-
> xhci.yaml
> index 1444d18ef9bc..63cbc2b62d18 100644
> --- a/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml
> +++ b/Documentation/devicetree/bindings/usb/mediatek,mtk-xhci.yaml
> @@ -67,6 +67,7 @@ properties:
>      maxItems: 1
>  
>    clocks:
> +    minItems: 1
>      items:
>        - description: Controller clock used by normal mode
>        - description: Reference clock used by low power mode etc
> @@ -75,8 +76,9 @@ properties:
>        - description: controller clock
>  
>    clock-names:
> +    minItems: 1
>      items:
> -      - const: sys_ck
> +      - const: sys_ck  # required, the following ones are optional
>        - const: ref_ck
>        - const: mcu_ck
>        - const: dma_ck

Reviewed-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>

Thanks a lot