RE: [PATCH v4 08/13] dt-bindings: display: bridge: Repurpose lvds-encoder

[Fabrizio Castro <fabrizio.castro@bp.renesas.com>]

Hi Laurent,

Thank you for your feedback!

> From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Sent: 19 November 2019 00:08
> Subject: Re: [PATCH v4 08/13] dt-bindings: display: bridge: Repurpose lvds-encoder
> 
> Hi Fabrizio,
> 
> Thank you for the patch.
> 
> On Wed, Nov 13, 2019 at 03:51:27PM +0000, Fabrizio Castro wrote:
> > In an effort to repurpose lvds-encoder.c to also serve the
> > function of LVDS decoders, we ended up defining a new "generic"
> > compatible string ("lvds-decoder"), therefore adapt the dt schema
> > to allow for the new compatible string.
> >
> > Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> >
> > ---
> > v3->v4:
> > * Improved title and description according to Laurent's comments
> > * Reworked definition of the compatible property
> > v2->v3:
> > * Extracted conversion to lvds-codec as per Rob's comment
> > v1->v2:
> > * Converted to dt-schema as per Neil's comment
> > ---
> >  .../{lvds-transmitter.yaml => lvds-codec.yaml}     | 54 +++++++++++++++++-----
> >  1 file changed, 42 insertions(+), 12 deletions(-)
> >  rename Documentation/devicetree/bindings/display/bridge/{lvds-transmitter.yaml => lvds-codec.yaml} (61%)
> >
> > diff --git a/Documentation/devicetree/bindings/display/bridge/lvds-transmitter.yaml
> b/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
> > similarity index 61%
> > rename from Documentation/devicetree/bindings/display/bridge/lvds-transmitter.yaml
> > rename to Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
> > index 27de616..0ecc8a4 100644
> > --- a/Documentation/devicetree/bindings/display/bridge/lvds-transmitter.yaml
> > +++ b/Documentation/devicetree/bindings/display/bridge/lvds-codec.yaml
> > @@ -1,17 +1,17 @@
> >  # SPDX-License-Identifier: GPL-2.0
> >  %YAML 1.2
> >  ---
> > -$id: http://devicetree.org/schemas/display/bridge/lvds-transmitter.yaml#
> > +$id: http://devicetree.org/schemas/display/bridge/lvds-codec.yaml#
> >  $schema: http://devicetree.org/meta-schemas/core.yaml#
> >
> > -title: Parallel to LVDS Encoder
> > +title: Transparent LVDS encoders and decoders
> >
> >  maintainers:
> >    - Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> >
> >  description: |
> > -  This binding supports the parallel to LVDS encoders that don't require any
> > -  configuration.
> > +  This binding supports transparent LVDS encoders and decoders that don't
> > +  require any configuration.
> >
> >    LVDS is a physical layer specification defined in ANSI/TIA/EIA-644-A. Multiple
> >    incompatible data link layers have been used over time to transmit image data
> > @@ -33,12 +33,14 @@ properties:
> >      description: |
> >        Must list the device specific compatible string first, followed by the
> >        generic compatible string.
> > -    items:
> > -      - enum:
> > -        - ti,ds90c185       # For the TI DS90C185 FPD-Link Serializer
> > -        - ti,ds90c187       # For the TI DS90C187 FPD-Link Serializer
> > -        - ti,sn75lvds83     # For the TI SN75LVDS83 FlatLink transmitter
> > -      - const: lvds-encoder # Generic LVDS encoder compatible fallback
> > +    oneOf:
> > +      - items:
> > +        - enum:
> > +          - ti,ds90c185       # For the TI DS90C185 FPD-Link Serializer
> > +          - ti,ds90c187       # For the TI DS90C187 FPD-Link Serializer
> > +          - ti,sn75lvds83     # For the TI SN75LVDS83 FlatLink transmitter
> > +        - const: lvds-encoder # Generic LVDS encoder compatible fallback
> > +      - const: lvds-decoder   # Generic LVDS decoders compatible fallback
> >
> >    ports:
> >      type: object
> > @@ -49,12 +51,14 @@ properties:
> >        port@0:
> >          type: object
> >          description: |
> > -          Port 0 is for parallel input
> > +          With LVDS encoders port 0 is for parallel input
> > +          With LVDS decoders port 0 is for LVDS input
> 
> How about
> 
>           For LVDS encoders, port 0 is the parallel input
>           For LVDS decoders, port 0 is the LVDS input

It's ok with me

> 
> >
> >        port@1:
> >          type: object
> >          description: |
> > -          Port 1 is for LVDS output
> > +          With LVDS encoders port 1 is for LVDS output
> > +          With LVDS decoders port 1 is for parallel output
> 
> And similarly here ?

Here too

> 
> If you're fine with this change there's no need to resubmit, I'll change
> this when applying, and

Yes please.

Thanks,
Fab

> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
> >
> >      required:
> >        - port@0
> > @@ -96,4 +100,30 @@ examples:
> >        };
> >      };
> >
> > +  - |
> > +    lvds-decoder {
> > +      compatible = "lvds-decoder";
> > +
> > +      ports {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        port@0 {
> > +          reg = <0>;
> > +
> > +          lvds_dec_in: endpoint {
> > +            remote-endpoint = <&display_out_lvds>;
> > +          };
> > +        };
> > +
> > +        port@1 {
> > +          reg = <1>;
> > +
> > +          lvds_dec_out: endpoint {
> > +            remote-endpoint = <&rgb_panel_in>;
> > +          };
> > +        };
> > +      };
> > +    };
> > +
> >  ...
> 
> --
> Regards,
> 
> Laurent Pinchart