Re: [PATCH 1/8] dt-bindings: soc: qcom: eud: Add phy related bindings

[Krzysztof Kozlowski <krzk@kernel.org>]

On 01/08/2024 00:23, Elson Serrao wrote:
> 
> 
> On 7/30/2024 10:33 PM, Krzysztof Kozlowski wrote:
>> On 31/07/2024 00:24, Elson Roy Serrao wrote:
>>> Embedded USB Debugger(EUD) being a High-Speed USB  hub needs
>>> HS-Phy support for it's operation. Hence document phy bindings
>>> to support this.
>>>
>>> Signed-off-by: Elson Roy Serrao <quic_eserrao@quicinc.com>
>>
>> A nit, subject: drop second/last, redundant "bindings". The
>> "dt-bindings" prefix is already stating that these are bindings.
>> See also:
>> https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18
>>
> Ack
>>> ---
>>>  .../devicetree/bindings/soc/qcom/qcom,eud.yaml       | 12 ++++++++++++
>>>  1 file changed, 12 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
>>> index f2c5ec7e6437..fca5b608ec63 100644
>>> --- a/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
>>> +++ b/Documentation/devicetree/bindings/soc/qcom/qcom,eud.yaml
>>> @@ -29,6 +29,14 @@ properties:
>>>      description: EUD interrupt
>>>      maxItems: 1
>>>  
>>> +  phys:
>>> +    items:
>>> +      - description: USB2/HS PHY needed for EUD functionality
>>> +
>>> +  phy-names:
>>> +    items:
>>> +      - const: usb2-phy
>>> +
>>>    ports:
>>>      $ref: /schemas/graph.yaml#/properties/ports
>>>      description:
>>> @@ -48,6 +56,8 @@ properties:
>>>  required:
>>>    - compatible
>>>    - reg
>>> +  - phys
>>> +  - phy-names
>>
>> That's an ABI break and nothing in commit msg justified it.
>>
> 
> Hi Krzysztof
> 
> Thank you for the review.
> I see that the only user for EUD as of now is QC sc7280 SoC where phy property

Did you ask all customers and all users of Linux kernel?

> is missing and EUD node is disabled. As described in my cover letter, HS phy
> support is needed for EUD functionality and this is applicable to all SoCs
> where EUD is to be enabled. Hence phy would be a required property.

Nothing in commit msg explained that, but I have a bit hard time to
believe that this never worked. If that's the case, say it explicitly in
commit msg - this was always broken.

> Given that the changes in this series are directly applicable to sc7280 as well,
> I will re-enable/rectify EUD feature on sc7280 SoC first, by adhering it to this binding
> requirement. That would address the ABI break. 

I don't understand what you are saying here.

> Once the base framework is set I shall extend it to sm8450 SoC.


Best regards,
Krzysztof