Re: [PATCH v3 2/3] dt-bindings: display: panel: Add binding document for Xinpeng XPP055C272

[Maxime Ripard]

On Tue, Dec 17, 2019 at 04:08:49PM +0100, Heiko Stübner wrote:
> Am Dienstag, 17. Dezember 2019, 15:24:46 CET schrieb Maxime Ripard:
> > Hi,
> >
> > On Tue, Dec 17, 2019 at 03:07:02PM +0100, Heiko Stuebner wrote:
> > > From: Heiko Stuebner <heiko.stuebner@xxxxxxxxxxxxxxxxxxxxx>
> > >
> > > The XPP055C272 is a 5.5" 720x1280 DSI display.
> > >
> > > changes in v2:
> > > - add size info into binding title (Sam)
> > > - add more required properties (Sam)
> > >
> > > Signed-off-by: Heiko Stuebner <heiko.stuebner@xxxxxxxxxxxxxxxxxxxxx>
> > > Reviewed-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
> > > ---
> > >  .../display/panel/xinpeng,xpp055c272.yaml     | 48 +++++++++++++++++++
> > >  1 file changed, 48 insertions(+)
> > >  create mode 100644 Documentation/devicetree/bindings/display/panel/xinpeng,xpp055c272.yaml
> > >
> > > diff --git a/Documentation/devicetree/bindings/display/panel/xinpeng,xpp055c272.yaml b/Documentation/devicetree/bindings/display/panel/xinpeng,xpp055c272.yaml
> > > new file mode 100644
> > > index 000000000000..2d0fc97d735c
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/display/panel/xinpeng,xpp055c272.yaml
> > > @@ -0,0 +1,48 @@
> > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/display/panel/sony,acx424akp.yaml#
> >
> > The ID doesn't match the file name.
> >
> > Did you run dt_bindings_check?
>
> Thanks for that pointer ... I did run dtbs_check on the binding and was
> sooo happy to not find any panel errors in the pages of other dt errors
> but till now didn't realize that there's also a dtbinding_check.

dt_bindings_check is a sanity check on the bindings
themselves. dtbs_check is using those bindings to check the device
trees.

dtbs_check used to have a dependency on dt_bindings_check, but it got
removed recently.

Maxime

>
> Will keep that in mind for future bindings  - and of course fix things
> in the next version.
>
>
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: Xinpeng XPP055C272 5.5in 720x1280 DSI panel
> > > +
> > > +maintainers:
> > > +  - Heiko Stuebner <heiko.stuebner@xxxxxxxxxxxxxxxxxxxxx>
> > > +
> > > +allOf:
> > > +  - $ref: panel-common.yaml#
> > > +
> > > +properties:
> > > +  compatible:
> > > +    const: xinpeng,xpp055c272
> > > +  reg: true
> > > +  backlight: true
> > > +  port: true
> >
> > What is the port supposed to be doing?
>
> Hooking the display up to the dsi controller. But you're right,
> works without port as well with these single-dsi displays.
>
> I just remember needing one for the Gru-Scarlet display that needed
> to connect to two dsi controllers.
>
> So I'll drop the port node here and from my board devicetree.

It's not really what I meant though :)

If it's needed then we should definitely have it, but we should
document our expectations here: is it the input port ? output? in
which case do we want to use it since it's optional, etc.

Maxime