Re: [PATCH v7 22/27] dt-bindings: allwinner: add H616 DE33 mixer binding

[Andre Przywara <andre.przywara@arm.com>]

On Mon, 17 Feb 2025 07:36:22 +1300
Ryan Walklin <ryan@testtoast.com> wrote:

Hi,

> The Allwinner H616 and variants have a new display engine revision
> (DE33).
> 
> The mixer configuration registers are significantly different to the DE3
> and DE2 revisions, being split into separate top and display blocks,
> therefore a fallback for the mixer compatible is not provided.
> 
> Add a display engine mixer binding for the DE33.
> 
> Signed-off-by: Ryan Walklin <ryan@testtoast.com>
> Acked-by: Conor Dooley <conor.dooley@microchip.com>
> Reviewed-by: Chen-Yu Tsai <wens@csie.org>
> 
> ---
> Changelog v2..v3:
> - Separate content into three patches for three separate subsystems
> 
> Changelog v5..v6:
> - increase reg maxItems to 3 and add conditional for h616-de33
> ---
>  .../allwinner,sun8i-a83t-de2-mixer.yaml       | 21 ++++++++++++++++++-
>  1 file changed, 20 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/allwinner,sun8i-a83t-de2-mixer.yaml b/Documentation/devicetree/bindings/display/allwinner,sun8i-a83t-de2-mixer.yaml
> index b75c1ec686ad2..274f5e6327333 100644
> --- a/Documentation/devicetree/bindings/display/allwinner,sun8i-a83t-de2-mixer.yaml
> +++ b/Documentation/devicetree/bindings/display/allwinner,sun8i-a83t-de2-mixer.yaml
> @@ -24,9 +24,11 @@ properties:
>        - allwinner,sun50i-a64-de2-mixer-0
>        - allwinner,sun50i-a64-de2-mixer-1
>        - allwinner,sun50i-h6-de3-mixer-0
> +      - allwinner,sun50i-h616-de33-mixer-0
>  
>    reg:
> -    maxItems: 1
> +    minItems: 1
> +    maxItems: 3

What are those three regions? I wonder if we should have reg-names here,
to fix the order, and to document them on the way?

>  
>    clocks:
>      items:
> @@ -61,6 +63,23 @@ properties:
>      required:
>        - port@1
>  
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          enum:
> +            - allwinner,sun50i-h616-de33-mixer-0
> +
> +    then:
> +      properties:
> +        reg:
> +          maxItems: 3

Should we override minItems here as well? I guess any driver would need
all three region to work?

Cheers,
Andre

> +
> +    else:
> +      properties:
> +        reg:
> +          maxItems: 1
> +
>  required:
>    - compatible
>    - reg