Re: [PATCH 01/12] dt-bindings: display: st: add new compatible to LTDC device

[Rob Herring <robh@kernel.org>]

On Fri, Jul 25, 2025 at 12:03:53PM +0200, Raphael Gallais-Pou wrote:
> The new STMicroelectronics SoC features a display controller similar to
> the one used in previous SoCs.  Because there is additional registers,
> it is incompatible with existing IPs.
> 
> Add the new name to the list of compatible string.
> 
> Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
> ---
>  .../devicetree/bindings/display/st,stm32-ltdc.yaml | 37 +++++++++++++++++++---
>  1 file changed, 33 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml b/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
> index d6ea4d62a2cfae26353c9f20a326a4329fed3a2f..546f57cb7a402b82e868aa05f874c65b8da19444 100644
> --- a/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
> +++ b/Documentation/devicetree/bindings/display/st,stm32-ltdc.yaml
> @@ -12,7 +12,9 @@ maintainers:
>  
>  properties:
>    compatible:
> -    const: st,stm32-ltdc
> +    enum:
> +      - st,stm32-ltdc
> +      - st,stm32mp25-ltdc
>  
>    reg:
>      maxItems: 1
> @@ -24,11 +26,12 @@ properties:
>      minItems: 1
>  
>    clocks:
> -    maxItems: 1
> +    minItems: 1
> +    maxItems: 4
>  
>    clock-names:
> -    items:
> -      - const: lcd
> +    minItems: 1
> +    maxItems: 4
>  
>    resets:
>      maxItems: 1
> @@ -51,6 +54,32 @@ required:
>    - resets
>    - port
>  
> +if:
> +  properties:
> +    compatible:
> +      contains:
> +        enum:
> +          - st,stm32-ltdc
> +then:
> +  properties:
> +    clocks:
> +      maxItems: 1
> +    clock-names:
> +      maxItems: 1
> +      items:
> +        - const: lcd
> +else:
> +  properties:
> +    clocks:
> +      maxItems: 4
> +    clock-names:
> +      maxItems: 4
> +      items:
> +      - const: bus
> +      - const: lcd

Why can't 'lcd' be 1st so you aren't changing positions? Keep the items 
list at the top level and just use minItems/maxItems in the if/then 
schemas.

> +      - const: ref
> +      - const: lvds
> +
>  additionalProperties: false
>  
>  examples:
> 
> -- 
> 2.25.1
>