RE: [PATCH v3 2/8] dt-bindings: display: Add idk-2121wr binding

[Fabrizio Castro <fabrizio.castro@xxxxxxxxxxxxxx>]

Hi Laurent,

Thank you for your feedback!

> From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Sent: 07 November 2019 18:12
> Subject: Re: [PATCH v3 2/8] dt-bindings: display: Add idk-2121wr binding
> 
> Hi Fabrizio,
> 
> Thank you for the patch.
> 
> On Wed, Aug 28, 2019 at 07:36:36PM +0100, Fabrizio Castro wrote:
> > Add binding for the idk-2121wr LVDS panel from Advantech.
> >
> > Some panel-specific documentation can be found here:
> > https://buy.advantech.eu/Displays/Embedded-LCD-Kits-High-Brightness/model-IDK-2121WR-K2FHA2E.htm
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro@xxxxxxxxxxxxxx>
> >
> > ---
> > v2->v3:
> > * new patch
> > ---
> >  .../display/panel/advantech,idk-2121wr.yaml        | 90 ++++++++++++++++++++++
> >  1 file changed, 90 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/display/panel/advantech,idk-2121wr.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/display/panel/advantech,idk-2121wr.yaml
> b/Documentation/devicetree/bindings/display/panel/advantech,idk-2121wr.yaml
> > new file mode 100644
> > index 0000000..b2ccdc8
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/display/panel/advantech,idk-2121wr.yaml
> > @@ -0,0 +1,90 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/display/panel/advantech,idk-2121wr.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Advantech IDK-2121WR 21.5" Full-HD dual-LVDS panel
> > +
> > +maintainers:
> > +  - Fabrizio Castro <fabrizio.castro@xxxxxxxxxxxxxx>
> > +  - Thierry Reding <thierry.reding@xxxxxxxxx>
> > +
> > +description: |
> > +  The IDK-2121WR from Advantech is a Full-HD dual-LVDS panel.
> > +
> > +  The panels expects odd pixels from the first port, and even pixels from
> 
> s/panels/panel/
> Maybe s/from the/on the/g ?

Will fix

> 
> > +  the second port, therefore the ports must be marked accordingly.
> > +
> > +allOf:
> > +  - $ref: lvds.yaml#
> > +  - $ref: ../bus-timings/lvds.yaml#
> > +
> > +properties:
> > +  compatible:
> > +    items:
> > +      - const: advantech,idk-2121wr
> > +      - {} # panel-lvds, but not listed here to avoid false select
> > +
> > +  data-mapping:
> > +    const: vesa-24
> > +
> > +  width-mm:
> > +    const: 476
> > +
> > +  height-mm:
> > +    const: 268
> > +
> > +  panel-timing: true
> > +  ports: true
> > +
> > +additionalProperties: false
> > +
> > +required:
> > +  - compatible
> 
> Shouldn't data-mapping, width-mm, height-mm and ports be required too ?

Those are required by lvds.yaml, and this file has a reference to it.
Anyhow, I think the best course of action is to merge this with the
generic bus-timings/lvds.yaml for the time being, and maybe split
them back later on once we have another use case.

Thanks,
Fab

> 
> As you mentioned in the cover letter, validating ports, port and the new
> dual-lvds-*-pixels properties would be nice. I'm not YAML schema
> specialist, so I'm fine with a best effort approach here, but as far as
> I understand Rob proposed a way forward, could you try it ?
> 
> Apart from that, the bindings look sne to me, so
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> 
> once the above issues get addressed.
> 
> > +
> > +examples:
> > +  - |+
> > +    panel-lvds {
> > +      compatible = "advantech,idk-2121wr", "panel-lvds";
> > +
> > +      width-mm = <476>;
> > +      height-mm = <268>;
> > +
> > +      data-mapping = "vesa-24";
> > +
> > +      panel-timing {
> > +        clock-frequency = <148500000>;
> > +        hactive = <1920>;
> > +        vactive = <1080>;
> > +        hsync-len = <44>;
> > +        hfront-porch = <88>;
> > +        hback-porch = <148>;
> > +        vfront-porch = <4>;
> > +        vback-porch = <36>;
> > +        vsync-len = <5>;
> > +      };
> > +
> > +      ports {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        port@0 {
> > +          reg = <0>;
> > +          dual-lvds-odd-pixels;
> > +          panel_in0: endpoint {
> > +            remote-endpoint = <&lvds0_out>;
> > +          };
> > +        };
> > +
> > +        port@1 {
> > +          reg = <1>;
> > +          dual-lvds-even-pixels;
> > +          panel_in1: endpoint {
> > +            remote-endpoint = <&lvds1_out>;
> > +          };
> > +        };
> > +      };
> > +    };
> > +
> > +...
> 
> --
> Regards,
> 
> Laurent Pinchart