dt-bindings: convert rockchip-drm.txt to rockchip-drm.yaml

Rockchip DRM master device

================================

The Rockchip DRM master device is a virtual device needed to list all

vop devices or other display interface nodes that comprise the

graphics subsystem.

Required properties:

- compatible: Should be "rockchip,display-subsystem"

- ports: Should contain a list of phandles pointing to display interface port

  of vop devices. vop definitions as defined in

  Documentation/devicetree/bindings/display/rockchip/rockchip-vop.txt

example:

display-subsystem {

	compatible = "rockchip,display-subsystem";

	ports = <&vopl_out>, <&vopb_out>;

};

# SPDX-License-Identifier: (GPL-2.0-only)

%YAML 1.2

---

$id: http://devicetree.org/schemas/display/rockchip/rockchip-drm.yaml#

$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Rockchip DRM master device

maintainers:

  - Sandy Huang <hjc@rock-chips.com>

  - Heiko Stuebner <heiko@sntech.de>

description: |

  The Rockchip DRM master device is a virtual device needed to list all

  vop devices or other display interface nodes that comprise the

  graphics subsystem.

properties:

  compatible:

    const: rockchip,display-subsystem

  ports:

    $ref: /schemas/types.yaml#/definitions/phandle-array

    description: |

      Should contain a list of phandles pointing to display interface port

      of vop devices. vop definitions as defined in

      Documentation/devicetree/bindings/display/rockchip/rockchip-vop.txt

required:

  - compatible

  - ports

additionalProperties: false

examples:

  - |

    display-subsystem {

        compatible = "rockchip,display-subsystem";

        ports = <&vopl_out>, <&vopb_out>;

    };