Re: [PATCH 1/7] dt-bindings: phy: qcom,sc8280xp-qmp-usb43dp: Add ports and orientation-switch

From: Bjorn Andersson
Date: Thu Apr 27 2023 - 15:52:46 EST


On Wed, Apr 26, 2023 at 11:21:29AM +0100, Bryan O'Donoghue wrote:
> On Tue, Apr 25, 2023 at 4:40 AM Bjorn Andersson
> <quic_bjorande@xxxxxxxxxxx> wrote:
> >
> > The QMP combo phy can be connected to a TCPM, a USB controller and a
> > DisplayPort controller for handling USB Type-C orientation switching
> > and propagating HPD signals.
> >
> > Extend the binding to allow these connections to be described.
> >
> > Signed-off-by: Bjorn Andersson <quic_bjorande@xxxxxxxxxxx>
> > ---
> > .../phy/qcom,sc8280xp-qmp-usb43dp-phy.yaml | 51 +++++++++++++++++++
> > 1 file changed, 51 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb43dp-phy.yaml b/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb43dp-phy.yaml
> > index 3cd5fc3e8fab..c037ac90ce7f 100644
> > --- a/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb43dp-phy.yaml
> > +++ b/Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-usb43dp-phy.yaml
> > @@ -60,6 +60,26 @@ properties:
> > description:
> > See include/dt-bindings/dt-bindings/phy/phy-qcom-qmp.h
> >
> > + orientation-switch:
> > + description:
> > + Flag the PHY as possible handler of USB Type-C orientation switching
> > + type: boolean
> > +
> > + ports:
> > + $ref: /schemas/graph.yaml#/properties/ports
> > + properties:
> > + port@0:
> > + $ref: /schemas/graph.yaml#/properties/port
> > + description: Output endpoint of the PHY
> > +
> > + port@1:
> > + $ref: /schemas/graph.yaml#/$defs/port-base
> > + description: Incoming endpoint from the USB controller
>
> Do you really need this one ?
>
> The controller doesn't process orientation switching.
>

I don't have a need for it, as we can deal with role switching by
connecting connector/port@0 to the dwc3.

But if we ever have a need to describe the dwc3 -> QMP -> connector path
in the of_graph I think it would look prettier to have USB input as
port@1 and DP input as port@2...

Do you have a concern with keeping it around in the DT (the
implementation doesn't need to care)?

Regards,
Bjorn