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

Harikrishna Shenoy posted 1 patch 3 months ago 
.../bindings/display/bridge/cdns,mhdp8546.yaml      | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
[PATCH] dt-bindings: drm/bridge: Update reg-name list for cdns,mhdp8546 compatible
Posted by Harikrishna Shenoy 3 months ago 
Remove j721e-intg register name from reg-name list for cdns,mhdp8546
compatible. The j721e-intg registers are specific to TI SoCs, so they
are not required for compatibles other than ti,j721e-mhdp8546.

Move the register name constraints to the appropriate compatibility
sections to ensure the correct register names are used with each
compatible value.

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/

 .../bindings/display/bridge/cdns,mhdp8546.yaml      | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
index c2b369456e4e2..2fdb4f7108ed5 100644
--- a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
+++ b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
@@ -30,10 +30,6 @@ properties:
 
   reg-names:
     minItems: 1
-    items:
-      - const: mhdptx
-      - const: j721e-intg
-      - const: mhdptx-sapb
 
   clocks:
     maxItems: 1
@@ -103,7 +99,10 @@ allOf:
           maxItems: 3
         reg-names:
           minItems: 2
-          maxItems: 3
+          items:
+            - const: mhdptx
+            - const: j721e-intg
+            - const: mhdptx-sapb
     else:
       properties:
         reg:
@@ -111,7 +110,9 @@ allOf:
           maxItems: 2
         reg-names:
           minItems: 1
-          maxItems: 2
+          items:
+            - const: mhdptx
+            - const: mhdptx-sapb
 
 required:
   - compatible
-- 
2.34.1
Re: [PATCH] dt-bindings: drm/bridge: Update reg-name list for cdns,mhdp8546 compatible
Posted by Krzysztof Kozlowski 3 months ago 
On 07/11/2025 14:15, Harikrishna Shenoy wrote:
> Remove j721e-intg register name from reg-name list for cdns,mhdp8546
> compatible. The j721e-intg registers are specific to TI SoCs, so they
> are not required for compatibles other than ti,j721e-mhdp8546.
> 
> Move the register name constraints to the appropriate compatibility
> sections to ensure the correct register names are used with each
> compatible value.
> 
> 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/
> 
>  .../bindings/display/bridge/cdns,mhdp8546.yaml      | 13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
> index c2b369456e4e2..2fdb4f7108ed5 100644
> --- a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
> +++ b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
> @@ -30,10 +30,6 @@ properties:
>  
>    reg-names:
>      minItems: 1
> -    items:
> -      - const: mhdptx
> -      - const: j721e-intg
> -      - const: mhdptx-sapb
>  
>    clocks:
>      maxItems: 1
> @@ -103,7 +99,10 @@ allOf:
>            maxItems: 3
>          reg-names:
>            minItems: 2
> -          maxItems: 3
> +          items:
> +            - const: mhdptx
> +            - const: j721e-intg
> +            - const: mhdptx-sapb
>      else:
>        properties:
>          reg:
> @@ -111,7 +110,9 @@ allOf:
>            maxItems: 2
>          reg-names:
>            minItems: 1
> -          maxItems: 2
> +          items:
> +            - const: mhdptx
> +            - const: mhdptx-sapb

This does not match regs now. Look which entry is the second - it is
always DSS_EDP0_INTG_CFG_VP.

Optional item should be the last, not the middle. That's why DT
maintainers ask (and it is even documented) to post complete bindings.
Complete means all registers, entire address space.

Best regards,
Krzysztof
Re: [PATCH] dt-bindings: drm/bridge: Update reg-name list for cdns,mhdp8546 compatible
Posted by Harikrishna shenoy 3 months ago 

On 07/11/25 18:57, Krzysztof Kozlowski wrote:
> On 07/11/2025 14:15, Harikrishna Shenoy wrote:
>> Remove j721e-intg register name from reg-name list for cdns,mhdp8546
>> compatible. The j721e-intg registers are specific to TI SoCs, so they
>> are not required for compatibles other than ti,j721e-mhdp8546.
>>
>> Move the register name constraints to the appropriate compatibility
>> sections to ensure the correct register names are used with each
>> compatible value.
>>
>> 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/
>>
>>   .../bindings/display/bridge/cdns,mhdp8546.yaml      | 13 +++++++------
>>   1 file changed, 7 insertions(+), 6 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
>> index c2b369456e4e2..2fdb4f7108ed5 100644
>> --- a/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
>> +++ b/Documentation/devicetree/bindings/display/bridge/cdns,mhdp8546.yaml
>> @@ -30,10 +30,6 @@ properties:
>>   
>>     reg-names:
>>       minItems: 1
>> -    items:
>> -      - const: mhdptx
>> -      - const: j721e-intg
>> -      - const: mhdptx-sapb
>>   
>>     clocks:
>>       maxItems: 1
>> @@ -103,7 +99,10 @@ allOf:
>>             maxItems: 3
>>           reg-names:
>>             minItems: 2
>> -          maxItems: 3
>> +          items:
>> +            - const: mhdptx
>> +            - const: j721e-intg
>> +            - const: mhdptx-sapb
>>       else:
>>         properties:
>>           reg:
>> @@ -111,7 +110,9 @@ allOf:
>>             maxItems: 2
>>           reg-names:
>>             minItems: 1
>> -          maxItems: 2
>> +          items:
>> +            - const: mhdptx
>> +            - const: mhdptx-sapb
> 
> This does not match regs now. Look which entry is the second - it is
> always DSS_EDP0_INTG_CFG_VP
> Optional item should be the last, not the middle. That's why DT

Hi Krzysztof,

Thanks for the review, will update the reg-description for 
ti,j721e-mhdp8546 j721e-intg is mandatory and for cdns,mhdp8546 
j721e-intg is
not needed, will update and separate the reg description list according
to compatibles as well.

> maintainers ask (and it is even documented) to post complete bindings.
> Complete means all registers, entire address space.
>

I understand the need to post complete bindings, but this is a fixes 
patch which tries to address the concerns raised in previous 
discussions, not sure if it would be appropriate to add other register
in address space like DSC which have not been updated in binding?

Regards,
Hari

> Best regards,
> Krzysztof

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