[PATCH RFC v2 1/5] dt-bindings: display: panel: Fix port binding

[Kory Maincent]

On Mon, 28 Apr 2025 09:32:21 +0200
Krzysztof Kozlowski <krzk at kernel.org> wrote:

> On Thu, Apr 24, 2025 at 05:07:39PM GMT, Kory Maincent wrote:
> > Faced a binding error check while adding the data-lanes property in the
> > ilitek,ili9881c binding. See the next patch for the binding changes.
> > Here is the error:
> > Documentation/devicetree/bindings/display/panel/ilitek,ili9881c.example.dtb:
> > panel at 0: port:endpoint: Unevaluated properties are not allowed
> > ('data-lanes' was unexpected)  
> 
> There is no error at this point so your rationale is not correct. You
> cannot use possible error as reason to fix something... You can use
> instead other arguments that the binding is incomplete or incorrect.

As I have said in the cover letter, I faced this error and this patch fixed it
but I didn't get the ins and outs.
Indeed, I didn't understand the conflict between the port definition in
panel-common and the panel binding change from the 2nd patch.

> > Change the reference of properties/port to $defs/port-base to makes it
> > work.
> > The only difference between port and port-base is the unevaluatedProperty
> > set to false. I have tried to use properties/port in both panel-common
> > and ilitek,ili9881c bindings but the error is still there. The only way
> > to not face the error is to use $defs/port-base reference. I don't
> > really understand the ins and outs, maybe it is a issue from the binding
> > check tool.
> > 
> > Signed-off-by: Kory Maincent <kory.maincent at bootlin.com>
> > ---
> > 
> > Changes in v2:
> > - New patch
> > ---
> >  Documentation/devicetree/bindings/display/panel/panel-common.yaml | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git
> > a/Documentation/devicetree/bindings/display/panel/panel-common.yaml
> > b/Documentation/devicetree/bindings/display/panel/panel-common.yaml index
> > 087415753d606ce67bceabaa9b0ba7d463282f92..635f67ced0cb7103684a1415ab740d83409a7dbb
> > 100644 ---
> > a/Documentation/devicetree/bindings/display/panel/panel-common.yaml +++
> > b/Documentation/devicetree/bindings/display/panel/panel-common.yaml @@
> > -76,7 +76,7 @@ properties: # Connectivity port:
> > -    $ref: /schemas/graph.yaml#/properties/port
> > +    $ref: /schemas/graph.yaml#/$defs/port-base  
> 
> This allows anything in the port in every other binding, so is not
> correct. You need to fully describe the port here with
> additionalProps:false, probably. Just like every other binding with
> port-base is doing.

Yeah that was expected.
As I said I tried with port-base but it throw me this error and I didn't manage
to remove it with only the panel binding change for now.

Regards,
-- 
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com