Re: [PATCH 2/4] dt-bindings: display: ti: Add schema for AM625 OLDI Transmitter

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

Hi Aradhya,

Thank you for the patch.

On Sun, May 12, 2024 at 01:00:53AM +0530, Aradhya Bhatia wrote:
> Add devicetree binding schema for AM625 OLDI Transmitters.
> 
> Signed-off-by: Aradhya Bhatia <a-bhatia1@ti.com>
> ---
>  .../bindings/display/ti/ti,am625-oldi.yaml    | 153 ++++++++++++++++++
>  MAINTAINERS                                   |   1 +
>  2 files changed, 154 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/ti/ti,am625-oldi.yaml
> 
> diff --git a/Documentation/devicetree/bindings/display/ti/ti,am625-oldi.yaml b/Documentation/devicetree/bindings/display/ti/ti,am625-oldi.yaml
> new file mode 100644
> index 000000000000..0a96e600bc0b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/ti/ti,am625-oldi.yaml
> @@ -0,0 +1,153 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/display/ti/ti,am625-oldi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Texas Instruments AM625 OLDI Transmitter
> +
> +maintainers:
> +  - Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> +  - Aradhya Bhatia <a-bhatia1@ti.com>
> +
> +description: |
> +  The AM625 TI Keystone OpenLDI transmitter (OLDI TX) supports serialized RGB
> +  pixel data transmission between host and flat panel display over LVDS (Low
> +  Voltage Differential Sampling) interface. The OLDI TX consists of 7-to-1 data
> +  serializers, and 4-data and 1-clock LVDS outputs. It supports the LVDS output
> +  formats "jeida-18", "jeida-24" and "vesa-18", and can accept 24-bit RGB or
> +  padded and un-padded 18-bit RGB bus formats as input.
> +
> +properties:
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +    description: serial clock input for the OLDI transmitters
> +
> +  clock-names:
> +    const: s_clk
> +
> +  ti,companion-oldi:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      phandle to companion OLDI transmitter. This property is mandatory for the
> +      primarty OLDI TX if the OLDI TXes are expected to work either in dual-lvds
> +      mode or in clone mode. This property should point to the secondary OLDI
> +      TX.
> +
> +  ti,secondary-oldi:
> +    type: boolean
> +    description: Boolean property to mark an OLDI TX as secondary node.
> +
> +  ti,oldi-io-ctrl:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      phandle to syscon device node mapping OLDI IO_CTRL registers found in the
> +      control MMR region. This property is needed for OLDI interface to work.
> +
> +  ports:
> +    $ref: /schemas/graph.yaml#/properties/ports
> +
> +    properties:
> +      port@0:
> +        $ref: /schemas/graph.yaml#/properties/port
> +        description: Parallel RGB input port
> +
> +      port@1:
> +        $ref: /schemas/graph.yaml#/properties/port
> +        description: LVDS output port
> +
> +    required:
> +      - port@0
> +      - port@1
> +
> +allOf:
> +  - if:
> +      properties:
> +        ti,secondary-oldi: true
> +    then:
> +      properties:
> +        ti,companion-oldi: false
> +        ti,oldi-io-ctrl: false
> +        clocks: false
> +        clock-names: false
> +
> +    else:
> +      required:
> +        - ti,oldi-io-ctrl
> +        - clocks
> +        - clock-names
> +
> +required:
> +  - reg
> +  - ports
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/soc/ti,sci_pm_domain.h>
> +
> +    oldi_txes {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        oldi: oldi@0 {
> +            reg = <0>;
> +            clocks = <&k3_clks 186 0>;
> +            clock-names = "s_clk";
> +            ti,oldi-io-ctrl = <&dss_oldi_io_ctrl>;

What bus does this device live on ? Couldn't the I/O register space be
referenced by the reg property ?

> +            ports {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                port@0 {
> +                    reg = <0>;
> +                    oldi_in: endpoint {
> +                        remote-endpoint = <&dpi0_out>;
> +                    };
> +                };
> +            };
> +        };
> +    };
> +
> +  - |
> +    #include <dt-bindings/soc/ti,sci_pm_domain.h>
> +
> +    oldi_txes {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        oldi0: oldi@0 {
> +            reg = <0>;
> +            clocks = <&k3_clks 186 0>;
> +            clock-names = "s_clk";
> +            ti,companion-oldi = <&oldi1>;
> +            ti,oldi-io-ctrl = <&dss_oldi_io_ctrl>;
> +            ports {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                port@0 {
> +                    reg = <0>;
> +                    oldi0_in: endpoint {
> +                        remote-endpoint = <&dpi0_out0>;
> +                    };
> +                };
> +            };
> +        };
> +        oldi1: oldi@1 {
> +            reg = <1>;
> +            ti,secondary-oldi;
> +            ports {
> +                #address-cells = <1>;
> +                #size-cells = <0>;
> +                port@0 {
> +                    reg = <0>;
> +                    oldi1_in: endpoint {
> +                        remote-endpoint = <&dpi0_out1>;
> +                    };
> +                };
> +            };
> +        };
> +    };
> +
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index c675fc296b19..4426c4d41a7f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -7480,6 +7480,7 @@ M:	Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
>  L:	dri-devel@lists.freedesktop.org
>  S:	Maintained
>  T:	git https://gitlab.freedesktop.org/drm/misc/kernel.git
> +F:	Documentation/devicetree/bindings/display/ti/ti,am625-oldi.yaml
>  F:	Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml
>  F:	Documentation/devicetree/bindings/display/ti/ti,j721e-dss.yaml
>  F:	Documentation/devicetree/bindings/display/ti/ti,k2g-dss.yaml

-- 
Regards,

Laurent Pinchart