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

["Luca Weiss" <luca.weiss@fairphone.com>]

On Fri Dec 13, 2024 at 10:34 AM CET, 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
> > +
> >              required:
> >                - data-lanes
> >  
> > diff --git a/Documentation/devicetree/bindings/media/qcom,msm8953-camss.yaml b/Documentation/devicetree/bindings/media/qcom,msm8953-camss.yaml
> > index 8856fba385b1123d748199b46c5009c97700ad9b..6d776b0ca71140c0816b246dbaf41ef376205bba 100644
> > --- a/Documentation/devicetree/bindings/media/qcom,msm8953-camss.yaml
> > +++ b/Documentation/devicetree/bindings/media/qcom,msm8953-camss.yaml
> > @@ -112,6 +112,11 @@ properties:
> >                  minItems: 1
> >                  maxItems: 4
> >  
> > +              bus-type:
> > +                enum:
> > +                  - 1 # MEDIA_BUS_TYPE_CSI2_CPHY
>
> Just 1
>
> > +                  - 4 # MEDIA_BUS_TYPE_CSI2_DPHY
>
> Just 4
>
> The type and meaning is already stated by video-interfaces and the
> binding headers.

This is actually something I find rather curious why this is not done
more obvious, e.g. there's basically no link that a '4' is
MEDIA_BUS_TYPE_CSI2_DPHY from dt-bindings/media/video-interfaces.h

video-interfaces.yaml only states "- 4 # MIPI CSI-2 D-PHY" and it's then
the users excercise to find MEDIA_BUS_TYPE_CSI2_DPHY for that.

Regards
Luca

>
> Anyway:
>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>
> Best regards,
> Krzysztof