Re: [PATCH V1 1/3] dt-bindings: ufs: qcom: Add reg and reg-names

[Ram Kumar Dwivedi]

On 30-Jul-25 2:41 PM, Krzysztof Kozlowski wrote:
> On 30/07/2025 10:22, Ram Kumar Dwivedi wrote:
>> Update the Qualcomm UFS device tree bindings to support Multi-Circular
>> Queue (MCQ) operation. This includes increasing the maximum number of
>> register entries from 2 to 3 and extending the accepted values for
>> reg-names to include "mcq_sqd" and "mcq_vs".
>>
>> These changes are required to enable MCQ support via Device Tree for
>> platforms such as SM8650 and SM8750.
>>
>> Signed-off-by: Ram Kumar Dwivedi <quic_rdwivedi@xxxxxxxxxxx>
>> ---
>>  .../devicetree/bindings/ufs/qcom,ufs.yaml     | 21 ++++++++++++-------
>>  1 file changed, 13 insertions(+), 8 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml b/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml
>> index 6c6043d9809e..de263118b552 100644
>> --- a/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml
>> +++ b/Documentation/devicetree/bindings/ufs/qcom,ufs.yaml
>> @@ -86,12 +86,17 @@ properties:
>>  
>>    reg:
>>      minItems: 1
>> -    maxItems: 2
>> +    maxItems: 3
>>  
>>    reg-names:
>> -    items:
>> -      - const: std
>> -      - const: ice
>> +    oneOf:
>> +      - items:
>> +          - const: std
>> +          - const: ice
>> +      - items:
>> +          - const: ufs_mem
>> +          - const: mcq_sqd
>> +          - const: mcq_vs
> 
> This is incompatible change and commit msg is inaccurate here. It says
> "extending" but you are not extending at all.
> 
> Recent qcom patches love to break ABI and impact users. No.
> 
> Best regards,
> Krzysztof


Hi Krzysztof,

Thanks for your feedback.

Regarding your concern about this being an incompatible change — could you please clarify what specific aspect you believe breaks compatibility? 
>From my side, I’ve carefully tested the patch and verified that it does not break any existing DTs. I ran the following command to validate against the schema:

make -j32 dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/ufs/qcom,ufs.yaml
make -j32 dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/ufs/qcom,ufs.yaml

There were no errors reported for any target DTB.

As for the commit message, I acknowledge your point and will revise it in the next patchset to more accurately reflect the nature of the change.

Best regards,
Ram.