Re: [PATCH] dt-bindings: media: Convert video-mux to DT schema

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Rob,

Thank you for the patch.

On Thu, Mar 11, 2021 at 04:40:42PM -0700, Rob Herring wrote:
> Now that we have the graph schema, convert the video-mux binding to DT
> schema.
> 
> Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
> Cc: linux-media@vger.kernel.org
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
>  .../devicetree/bindings/media/video-mux.txt   | 60 ------------
>  .../devicetree/bindings/media/video-mux.yaml  | 93 +++++++++++++++++++
>  2 files changed, 93 insertions(+), 60 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/media/video-mux.txt
>  create mode 100644 Documentation/devicetree/bindings/media/video-mux.yaml
> 
> diff --git a/Documentation/devicetree/bindings/media/video-mux.txt b/Documentation/devicetree/bindings/media/video-mux.txt
> deleted file mode 100644
> index 63b9dc913e45..000000000000
> --- a/Documentation/devicetree/bindings/media/video-mux.txt
> +++ /dev/null
> @@ -1,60 +0,0 @@
> -Video Multiplexer
> -=================
> -
> -Video multiplexers allow to select between multiple input ports. Video received
> -on the active input port is passed through to the output port. Muxes described
> -by this binding are controlled by a multiplexer controller that is described by
> -the bindings in Documentation/devicetree/bindings/mux/mux-controller.txt
> -
> -Required properties:
> -- compatible : should be "video-mux"
> -- mux-controls : mux controller node to use for operating the mux
> -- #address-cells: should be <1>
> -- #size-cells: should be <0>
> -- port@*: at least three port nodes containing endpoints connecting to the
> -  source and sink devices according to of_graph bindings. The last port is
> -  the output port, all others are inputs.
> -
> -Optionally, #address-cells, #size-cells, and port nodes can be grouped under a
> -ports node as described in Documentation/devicetree/bindings/graph.txt.
> -
> -Example:
> -
> -	mux: mux-controller {
> -		compatible = "gpio-mux";
> -		#mux-control-cells = <0>;
> -
> -		mux-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>;
> -	};
> -
> -	video-mux {
> -		compatible = "video-mux";
> -		mux-controls = <&mux>;
> -		#address-cells = <1>;
> -		#size-cells = <0>;
> -
> -		port@0 {
> -			reg = <0>;
> -
> -			mux_in0: endpoint {
> -				remote-endpoint = <&video_source0_out>;
> -			};
> -		};
> -
> -		port@1 {
> -			reg = <1>;
> -
> -			mux_in1: endpoint {
> -				remote-endpoint = <&video_source1_out>;
> -			};
> -		};
> -
> -		port@2 {
> -			reg = <2>;
> -
> -			mux_out: endpoint {
> -				remote-endpoint = <&capture_interface_in>;
> -			};
> -		};
> -	};
> -};
> diff --git a/Documentation/devicetree/bindings/media/video-mux.yaml b/Documentation/devicetree/bindings/media/video-mux.yaml
> new file mode 100644
> index 000000000000..780fbbd46a38
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/video-mux.yaml
> @@ -0,0 +1,93 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/media/video-mux.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Video Multiplexer
> +
> +maintainers:
> +  - Sakari Ailus <sakari.ailus@linux.intel.com>
> +  - Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> +
> +description:
> +  Video multiplexers allow to select between multiple input ports. Video
> +  received on the active input port is passed through to the output port. Muxes
> +  described by this binding are controlled by a multiplexer controller.
> +
> +properties:
> +  compatible:
> +    const: video-mux
> +
> +  mux-controls:
> +    maxItems: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +  ports:
> +    $ref: /schemas/graph.yaml#/properties/ports
> +
> +    patternProperties:
> +      '^port@':
> +        $ref: /schemas/graph.yaml#/properties/port

Should we require at least port@0, port@1 and port@2 ?

> +
> +patternProperties:
> +  '^port@':
> +    $ref: /schemas/graph.yaml#/properties/port
> +    description:
> +      At least three port nodes containing endpoints connecting to the source
> +      and sink devices according to of_graph bindings. The last port is the
> +      output port, all others are inputs.
> +
> +required:
> +  - compatible
> +  - mux-controls

Should a constraint be added to ensure that either a ports node or
port@0, port@1 and port@2 nodes exists ?

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    mux: mux-controller {
> +        compatible = "gpio-mux";
> +        #mux-control-cells = <0>;
> +
> +        mux-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>;
> +    };
> +
> +    video-mux {
> +        compatible = "video-mux";
> +        mux-controls = <&mux>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        port@0 {
> +            reg = <0>;
> +
> +            mux_in0: endpoint {
> +                remote-endpoint = <&video_source0_out>;
> +            };
> +        };
> +
> +        port@1 {
> +            reg = <1>;
> +
> +            mux_in1: endpoint {
> +                remote-endpoint = <&video_source1_out>;
> +            };
> +        };
> +
> +        port@2 {
> +            reg = <2>;
> +
> +            mux_out: endpoint {
> +                remote-endpoint = <&capture_interface_in>;
> +            };
> +        };
> +    };
> +...

-- 
Regards,

Laurent Pinchart