RE: [PATCH v4 1/2] dt-bindings: it6505: add properties to restrict output bandwidth

From: allen.chen
Date: Thu Oct 13 2022 - 23:28:46 EST


Hi

-----Original Message-----
From: Rob Herring <robh@xxxxxxxxxx>
Sent: Friday, October 14, 2022 3:20 AM
To: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>; Allen Chen (陳柏宇) <allen.chen@xxxxxxxxxx>
Cc: Pin-yen Lin <treapking@xxxxxxxxxxxx>; Jau-Chih Tseng (曾昭智) <Jau-Chih.Tseng@xxxxxxxxxx>; Kenneth Hung (洪家倫) <Kenneth.Hung@xxxxxxxxxx>; Hermes Wu (吳佳宏) <Hermes.Wu@xxxxxxxxxx>; Andrzej Hajda <andrzej.hajda@xxxxxxxxx>; Neil Armstrong <narmstrong@xxxxxxxxxxxx>; Robert Foss <robert.foss@xxxxxxxxxx>; Jonas Karlman <jonas@xxxxxxxxx>; Jernej Skrabec <jernej.skrabec@xxxxxxxxx>; David Airlie <airlied@xxxxxxxx>; Daniel Vetter <daniel@xxxxxxxx>; Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx>; open list:DRM DRIVERS <dri-devel@xxxxxxxxxxxxxxxxxxxxx>; open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS <devicetree@xxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx>
Subject: Re: [PATCH v4 1/2] dt-bindings: it6505: add properties to restrict output bandwidth

On Thu, Oct 13, 2022 at 02:05:45PM +0300, Laurent Pinchart wrote:
> Hi Allen,
>
> Thank you for the patch.
>
> On Thu, Oct 13, 2022 at 06:51:13PM +0800, allen wrote:
> > From: allen chen <allen.chen@xxxxxxxxxx>
> >
> > Add properties to restrict dp output data-lanes and clock.
> >
> > Signed-off-by: Pin-Yen Lin <treapking@xxxxxxxxxxxx>
> > Signed-off-by: Allen Chen <allen.chen@xxxxxxxxxx>
> > ---
> > .../bindings/display/bridge/ite,it6505.yaml | 43 +++++++++++++++++++
> > 1 file changed, 43 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> > b/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> > index 833d11b2303a7..f2c3d1d10359e 100644
> > ---
> > a/Documentation/devicetree/bindings/display/bridge/ite,it6505.yaml
> > +++ b/Documentation/devicetree/bindings/display/bridge/ite,it6505.ya
> > +++ ml
> > @@ -52,10 +52,51 @@ properties:
> > maxItems: 1
> > description: extcon specifier for the Power Delivery
> >
> > + data-lanes:
> > + oneOf:
> > + - minItems: 1
> > + maxItems: 1
> > + uniqueItems: true
> > + items:
> > + enum:
> > + - 0
> > + - 1
> > + description: For one lane operation.
> > +
> > + - minItems: 2
> > + maxItems: 2
> > + uniqueItems: true
> > + items:
> > + enum:
> > + - 0
> > + - 1
> > + description: For two lanes operation.
> > +
> > + - minItems: 4
> > + maxItems: 4
> > + uniqueItems: true
> > + items:
> > + enum:
> > + - 0
> > + - 1
> > + - 2
> > + - 3
> > + description: For four lanes operation.
>
> The data lanes should be in the output endpoint. If there's no output
> port, one should be added.
>
==> In this dt-binding, our output point is "extcon" so doesn't have output endpoint.
I don't know how to add the endpoint.
If need to add the endpoint to this dt-binding, what is your recommend about adding the endpoint?
By the way, Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> said we could put "data-lanes" here.
> > +
> > port:
> > $ref: /schemas/graph.yaml#/properties/port

To fix the error, this must be:

$ref: /schemas/graph.yaml#/$defs/port-base
unevaluatedProperties: false

> > description: A port node pointing to DPI host port node
> >
> > + properties:
> > + endpoint:
> > + $ref: /schemas/graph.yaml#/$defs/endpoint-base
> > +
> > + properties:
> > + link-frequencies:
> > + minItems: 1
> > + maxItems: 1
> > + description: Allowed max link frequencies in Hz.
> > +
> > required:
> > - compatible
> > - ovdd-supply
> > @@ -84,10 +125,12 @@ examples:
> > pwr18-supply = <&it6505_pp18_reg>;
> > reset-gpios = <&pio 179 1>;
> > extcon = <&usbc_extcon>;
> > + data-lanes = <0 1>;
> >
> > port {
> > it6505_in: endpoint {
> > remote-endpoint = <&dpi_out>;
> > + link-frequencies = /bits/ 64 <150000000>;
> > };
> > };
> > };
>
> --
> Regards,
>
> Laurent Pinchart
>