Re: [PATCH v11 2/7] dt-bindings: media: qcom,x1e80100-camss: Add support for combo-mode endpoints

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

On 3/26/26 03:28, Bryan O'Donoghue wrote:
> Qualcomm CSI2 PHYs support a mode where two sensors may be attached to the
> one CSIPHY.
> 
> When we have one endpoint we may have
> - DPHY 1, 2 or 4 data lanes + 1 clock lane
> - CPHY 3 wire data lane
> 
> When we have two endpoints this indicates the special fixed combo-mode.
> - DPHY endpoint0 => 2+1 and endpoint1 => 1+1 data-lane/clock-lane combination.
> 
> Reviewed-by: Christopher Obbard <christopher.obbard@linaro.org>
> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
> ---
>   .../bindings/media/qcom,x1e80100-camss.yaml        | 69 ++++++++++++++++++++--
>   1 file changed, 65 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml b/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml
> index c17b9757b2c86..f44138f522bba 100644
> --- a/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml
> +++ b/Documentation/devicetree/bindings/media/qcom,x1e80100-camss.yaml
> @@ -148,7 +148,8 @@ properties:
>       $ref: /schemas/graph.yaml#/properties/ports
>   
>       description:
> -      CSI input ports.
> +      CSI input ports. Supports either standard single sensor mode or
> +      Qualcomm's combo mode with one sensor in 2x1 + 1x1 data-lane, clock-lane mode.
>   
>       patternProperties:
>         "^port@[0-3]$":
> @@ -156,26 +157,86 @@ properties:
>           unevaluatedProperties: false
>   
>           description:
> -          Input port for receiving CSI data from a CSIPHY.
> +          Input port for receiving CSI data.
>   
>           properties:
> -          endpoint:
> +          endpoint@0:
>               $ref: video-interfaces.yaml#
>               unevaluatedProperties: false
>   
> +            description:
> +              Endpoint for receiving a single sensor input (or first leg of combo).
> +
>               properties:
>                 data-lanes:
>                   minItems: 1
> -                maxItems: 4
> +                maxItems: 4 # Base max allows 4 (for D-PHY)
> +
> +              clock-lanes:
> +                maxItems: 1
>   
>                 bus-type:
>                   enum:
>                     - 1 # MEDIA_BUS_TYPE_CSI2_CPHY
>                     - 4 # MEDIA_BUS_TYPE_CSI2_DPHY
>   
> +          endpoint@1:
> +            $ref: video-interfaces.yaml#
> +            unevaluatedProperties: false
> +
> +            description:
> +              Endpoint for receiving the second leg of a combo sensor input.
> +
> +            properties:
> +              data-lanes:
> +                maxItems: 1
> +
> +              clock-lanes:
> +                maxItems: 1
> +
> +              bus-type:
> +                const: 4 # Combo is D-PHY specific
> +

It's unclear why both 'bus-type' and 'phys' cell argument are needed
at the same time, they are equal and thus one of two is redundant.

-- 
Best wishes,
Vladimir