Re: [PATCH v3] dt-bindings: drm/bridge: Update reg-name and reg description list for cdns,mhdp8546 compatible

[Krzysztof Kozlowski <krzk@kernel.org>]

On Fri, Nov 21, 2025 at 06:04:37PM +0530, Harikrishna Shenoy wrote:
> Remove j721e-intg register name from reg-name list for cdns,mhdp8546
> compatible. The j721e-integ registers are specific to TI SoCs, so they
> are not required for compatibles other than ti,j721e-mhdp8546.
> 
> Update reg and reg-names top level constraints with lists according
> to compatibles.
> 
> Move the register name constraints and reg description list to the
> appropriate compatibility sections to ensure the correct register
> names are used with each compatible value also adding the DSC register
> to make bindings align with what the hardware supports.
> 
> Fixes: 7169d082e7e6 ("dt-bindings: drm/bridge: MHDP8546 bridge binding changes for HDCP")
> Signed-off-by: Harikrishna Shenoy <h-shenoy@ti.com>
> ---
> 
> Links to some discussions pointing to need for a fixes patch: 
> https://lore.kernel.org/all/20250903220312.GA2903503-robh@kernel.org/
> https://lore.kernel.org/all/d2367789-6b54-4fc2-bb7c-609c0fe084d3@ti.com/
> 
> Link to v2:
> <https://lore.kernel.org/all/20251119122447.514729-1-h-shenoy@ti.com/>
> 
> Changelog v2 --> v3:
> -Add the reg description list and reg-name list in top level constraints
> using oneOf for either of compatible.
> Logs after testing some cases: https://gist.github.com/h-shenoy/a422f7278859cd95447e674963caabd9
> 
> Link to v1:
> <https://lore.kernel.org/all/20251107131535.1841393-1-h-shenoy@ti.com/>
> 
> Changelog v1 --> v2:
> -Update the reg description list for each compatible and add register space
> for dsc to make the bindings reflect what hardware supports although 
> the driver doesn't support dsc yet.
> 
> Note: j721e-integ are not optional registers for ti-compatible.
> 
>  .../display/bridge/cdns,mhdp8546.yaml         | 85 ++++++++++++++-----
>  1 file changed, 66 insertions(+), 19 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
> index c2b369456e4e2..632595ef32f63 100644
> --- a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
> @@ -17,23 +17,45 @@ properties:
>        - ti,j721e-mhdp8546
>  
>    reg:
> -    minItems: 1
> -    items:
> -      - description:
> -          Register block of mhdptx apb registers up to PHY mapped area (AUX_CONFIG_P).
> -          The AUX and PMA registers are not part of this range, they are instead
> -          included in the associated PHY.
> -      - description:
> -          Register block for DSS_EDP0_INTG_CFG_VP registers in case of TI J7 SoCs.
> -      - description:
> -          Register block of mhdptx sapb registers.
> +    oneOf:
> +      - minItems: 2
> +      - items:

This is wrong syntax. You created here a list, so you now allow
anything with minItems 2.

> +          - description:
> +              Register block of mhdptx apb registers up to PHY mapped area (AUX_CONFIG_P).
> +              The AUX and PMA registers are not part of this range, they are instead
> +              included in the associated PHY.
> +          - description:
> +              Register block for DSS_EDP0_INTG_CFG_VP registers in case of TI J7 SoCs.
> +          - description:
> +              Register block of mhdptx sapb registers.
> +          - description:
> +              Register block for mhdptx DSC encoder registers.
> +
> +      - minItems: 1

Actually anything with minItems 1... I asked for list of TWO, not FOUR,
items. Or if syntax is getting to complicated, just min and maxItems.


> +      - items:
> +          - description:
> +              Register block of mhdptx apb registers up to PHY mapped area (AUX_CONFIG_P).
> +              The AUX and PMA registers are not part of this range, they are instead
> +              included in the associated PHY.
> +          - description:
> +              Register block of mhdptx sapb registers.
> +          - description:
> +              Register block for mhdptx DSC encoder registers.
>  
>    reg-names:
> -    minItems: 1
> -    items:
> -      - const: mhdptx
> -      - const: j721e-intg
> -      - const: mhdptx-sapb
> +    oneOf:
> +      - minItems: 2
> +      - items:

Also wrong.

> +          - const: mhdptx
> +          - const: j721e-intg
> +          - const: mhdptx-sapb
> +          - const: dsc
> +
> +      - minItems: 1
> +      - items:
> +          - const: mhdptx
> +          - const: mhdptx-sapb
> +          - const: dsc
>  
>    clocks:
>      maxItems: 1
> @@ -100,18 +122,43 @@ allOf:
>        properties:
>          reg:
>            minItems: 2
> -          maxItems: 3

Your commit msg says you "remove" but here you ADD one more item, thus
growing this 3->4.

How remove can result in 3 becoming 4?


Best regards,
Krzysztof