[PATCH v3 1/5] dt-bindings: display: verisilicon,dc: generalize for single-output variants

[Krzysztof Kozlowski]

On Mon, Jun 08, 2026 at 10:32:33AM +0800, Joey Lu wrote:
> The existing schema hard-codes the five-clock/three-reset/dual-port
> topology of the DC8200 IP block, preventing reuse for single-output
> variants such as the Verisilicon DCUltraLite used in the Nuvoton MA35D1
> SoC.
> 
> Rework the schema so that variant-specific constraints are expressed via
> allOf/if blocks:
> 
> - Add nuvoton,ma35d1-dcu to the SoC-specific compatible enum.  The
>   generic verisilicon,dc fallback remains the driver-binding string.
> - Relax the top-level clocks/resets definitions to minItems ranges so
>   the base schema accepts both variants.
> - Keep ports in the global required list and keep additionalProperties
>   tightened to unevaluatedProperties.
> - Add an allOf/if block for thead,th1520-dc8200: five-clock (core, axi,
>   ahb, pix0, pix1), three-reset (core, axi, ahb).
> - Add an allOf/if block for nuvoton,ma35d1-dcu: two-clock (core, pix0),
>   one-reset (core).
> - Fix a stray space in the port at 0 description.
> - Add a DT example for the Nuvoton MA35D1 DCU Lite using ports/port at 0.
> 
> Signed-off-by: Joey Lu <a0987203069 at gmail.com>
> ---
>  .../bindings/display/verisilicon,dc.yaml      | 103 +++++++++++++++---
>  1 file changed, 90 insertions(+), 13 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/verisilicon,dc.yaml b/Documentation/devicetree/bindings/display/verisilicon,dc.yaml
> index 9dc35ab973f2..db0260d874c5 100644
> --- a/Documentation/devicetree/bindings/display/verisilicon,dc.yaml
> +++ b/Documentation/devicetree/bindings/display/verisilicon,dc.yaml
> @@ -17,7 +17,8 @@ properties:
>      items:
>        - enum:
>            - thead,th1520-dc8200
> -      - const: verisilicon,dc # DC IPs have discoverable ID/revision registers
> +          - nuvoton,ma35d1-dcu
> +      - const: verisilicon,dc  # DC IPs have discoverable ID/revision registers

Why do you need to change indentation? Why introducing irrelevant
changes to the diff?

>  
>    reg:
>      maxItems: 1
> @@ -26,6 +27,7 @@ properties:
>      maxItems: 1
>  
>    clocks:
> +    minItems: 2
>      items:
>        - description: DC Core clock
>        - description: DMA AXI bus clock

That's not true anymore. In such case the list should also be defined
per variant and here only min/maxItems.


> @@ -34,24 +36,19 @@ properties:
>        - description: Pixel clock of output 1
>  
>    clock-names:
> -    items:
> -      - const: core
> -      - const: axi
> -      - const: ahb
> -      - const: pix0
> -      - const: pix1
> +    minItems: 2
> +    maxItems: 5
>  
>    resets:
> +    minItems: 1
>      items:
>        - description: DC Core reset
>        - description: DMA AXI bus reset
>        - description: Configuration AHB bus reset
>  
>    reset-names:
> -    items:
> -      - const: core
> -      - const: axi
> -      - const: ahb

This stays, with minItems. Variants only need min/maxItems



> +    minItems: 1
> +    maxItems: 3
>  
>    ports:
>      $ref: /schemas/graph.yaml#/properties/ports
> @@ -59,7 +56,7 @@ properties:
>      properties:
>        port at 0:
>          $ref: /schemas/graph.yaml#/properties/port
> -        description: The first output channel , endpoint 0 should be
> +        description: The first output channel, endpoint 0 should be
>            used for DPI format output and endpoint 1 should be used
>            for DP format output.
>  
> @@ -77,7 +74,60 @@ required:
>    - clock-names
>    - ports
>  
> -additionalProperties: false
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: thead,th1520-dc8200
> +    then:
> +      properties:
> +        clocks:
> +          minItems: 5
> +          maxItems: 5
> +
> +        clock-names:
> +          items:
> +            - const: core
> +            - const: axi
> +            - const: ahb
> +            - const: pix0
> +            - const: pix1
> +
> +        resets:
> +          minItems: 3
> +          maxItems: 3
> +
> +        reset-names:

minItems: 3

> +          items:
> +            - const: core
> +            - const: axi
> +            - const: ahb
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: nuvoton,ma35d1-dcu
> +    then:
> +      properties:
> +        clocks:
> +          minItems: 2
> +          maxItems: 2
> +
> +        clock-names:
> +          items:
> +            - const: core
> +            - const: pix0
> +
> +        resets:
> +          maxItems: 1
> +
> +        reset-names:

maxItems: 1

> +          items:
> +            - const: core
> +
> +unevaluatedProperties: false

Stop making random changes to the binding.

Best regards,
Krzysztof