Re: [PATCH 1/2] media: dt-bindings: media: camss: Restrict bus-type property

[Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>]

On 12/13/24 11:34, Krzysztof Kozlowski wrote:
> On Mon, Dec 09, 2024 at 01:01:05PM +0100, Luca Weiss wrote:
>> The CSIPHY of Qualcomm SoCs support both D-PHY and C-PHY standards for
>> CSI-2, but not any others so restrict the bus-type property describing
>> this to the supported values.
>>
>> The only exception here is MSM8916 which only supports D-PHY. C-PHY was
>> introduced with newer SoCs.
>>
>> Do note, that currently the Linux driver only supports D-PHY.
>>
>> Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
>> ---
>>   .../bindings/media/qcom,msm8916-camss.yaml         |  8 ++++++
>>   .../bindings/media/qcom,msm8953-camss.yaml         | 15 +++++++++++
>>   .../bindings/media/qcom,msm8996-camss.yaml         | 20 +++++++++++++++
>>   .../bindings/media/qcom,sc8280xp-camss.yaml        | 20 +++++++++++++++
>>   .../bindings/media/qcom,sdm660-camss.yaml          | 20 +++++++++++++++
>>   .../bindings/media/qcom,sdm845-camss.yaml          | 20 +++++++++++++++
>>   .../bindings/media/qcom,sm8250-camss.yaml          | 30 ++++++++++++++++++++++
>>   7 files changed, 133 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/media/qcom,msm8916-camss.yaml b/Documentation/devicetree/bindings/media/qcom,msm8916-camss.yaml
>> index 9cc0a968a401836814560c1af3ee84d946500b4f..3de2a3d2b5b761106975aab65ff614b2ef579ef5 100644
>> --- a/Documentation/devicetree/bindings/media/qcom,msm8916-camss.yaml
>> +++ b/Documentation/devicetree/bindings/media/qcom,msm8916-camss.yaml
>> @@ -94,6 +94,10 @@ properties:
>>                   minItems: 1
>>                   maxItems: 4
>>   
>> +              bus-type:
>> +                enum:
>> +                  - 4 # MEDIA_BUS_TYPE_CSI2_DPHY
>> +
>>               required:
>>                 - data-lanes
>>   
>> @@ -113,6 +117,10 @@ properties:
>>                   minItems: 1
>>                   maxItems: 4
>>   
>> +              bus-type:
>> +                enum:
>> +                  - 4 # MEDIA_BUS_TYPE_CSI2_DPHY
>> +

But is it really needed to specify the single supported bus-type?

I believe it is not, at least it's not ever done for other media devices
like sensors.

Here I would prefer to get a comment from Linux Media and/or DTB experts.

--
Best wishes,
Vladimir