Re: [PATCH v8 1/2] dt-bindings: phy: qcom: Add CSI2 C-PHY/DPHY schema

[Vladimir Zapolskiy]

On 6/3/26 01:51, Bryan O'Donoghue wrote:
> On 02/06/2026 22:59, Vladimir Zapolskiy wrote:
> > On 5/23/26 05:48, Bryan O'Donoghue wrote:
> > > Add a base schema initially compatible with x1e80100 to describe MIPI CSI2
> > > PHY devices.
> > >
> > > The hardware can support both CPHY, DPHY and a special split-mode DPHY.
> > >
> > > The schema here defines three ports:
> > >
> > > port@0:
> > >        The first input port where a sensor is always required.
> > >
> > > port@1:
> > >        A second optional input port which if present implies DPHY split-mode.
> > >
> > > port@2:
> > >        A third always required output port which connects to the controller.
> >
> > This port numeration is imperfect, because port@0 and port@2 are required,
> > while middle port@1 is optional.
> >
> > Like it was stated before a number of times, it seems natural to operate
> > with two ports, where input port may have two endpoints rather than 3 ports,
> > also that approach solves the problem of a hole in the port numeration.
>
> Can you confirm this is what you are after ?
>
> port@0 {
>       #address-cells = <1>;
>       #size-cells = <0>;
>
>       endpoint@0 {              /* primary sensor */
>           reg = <0>;
>           data-lanes = <0 1 2 3>;
>           remote-endpoint = <&sensor0_out>;
>       };
>
>       endpoint@1 {              /* split-mode second sensor, optional */
>           reg = <1>;
>           data-lanes = <0>;
>           remote-endpoint = <&sensor1_out>;
>       };
> };
>
> port@1 {                     /* output to CAMSS, was port@2 */
>       endpoint { remote-endpoint = <&controller_in>; };
> };
>
> This works for me BTW.

Something like this will be a much better description, below are additional
notes:

1. for endpoints to sensors data-lanes and clock-lanes should be specified,
2. as it was stated before the numeration should start from 1,
3. output port may be just removed, otherwise there are supposed to be 3 (!)
links between the umbrella CAMSS and children CSIPHY devices, namely the
links are a) parent-child layout, b) phy connection and c) media endpoints,
it sounds as an excessive overload, where a simplification is possible.

--
Best wishes,
Vladimir