dt-bindings: display: convert Atmel's HLCDC to DT schema

# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)

%YAML 1.2

---

$id: http://devicetree.org/schemas/display/atmel/atmel,hlcdc-display-controller.yaml#

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

title: Atmel's High LCD Controller (HLCDC)

maintainers:

  - Nicolas Ferre <nicolas.ferre@microchip.com>

  - Alexandre Belloni <alexandre.belloni@bootlin.com>

  - Claudiu Beznea <claudiu.beznea@tuxon.dev>

description:

  The LCD Controller (LCDC) consists of logic for transferring LCD image

  data from an external display buffer to a TFT LCD panel. The LCDC has one

  display input buffer per layer that fetches pixels through the single bus

  host interface and a look-up table to allow palletized display

  configurations.

properties:

  compatible:

    const: atmel,hlcdc-display-controller

  '#address-cells':

    const: 1

  '#size-cells':

    const: 0

  port@0:

    $ref: /schemas/graph.yaml#/$defs/port-base

    unevaluatedProperties: false

    description:

      Output endpoint of the controller, connecting the LCD panel signals.

    properties:

      '#address-cells':

        const: 1

      '#size-cells':

        const: 0

      reg:

        maxItems: 1

      endpoint:

        $ref: /schemas/media/video-interfaces.yaml#

        unevaluatedProperties: false

        description:

          Endpoint connecting the LCD panel signals.

        properties:

          bus-width:

            enum: [ 12, 16, 18, 24 ]

required:

  - '#address-cells'

  - '#size-cells'

  - compatible

  - port@0

additionalProperties: false

Device-Tree bindings for Atmel's HLCDC (High LCD Controller) DRM driver

The Atmel HLCDC Display Controller is subdevice of the HLCDC MFD device.

See ../../mfd/atmel-hlcdc.txt for more details.

Required properties:

 - compatible: value should be "atmel,hlcdc-display-controller"

 - pinctrl-names: the pin control state names. Should contain "default".

 - pinctrl-0: should contain the default pinctrl states.

 - #address-cells: should be set to 1.

 - #size-cells: should be set to 0.

Required children nodes:

 Children nodes are encoding available output ports and their connections

 to external devices using the OF graph representation (see ../graph.txt).

 At least one port node is required.

Optional properties in grandchild nodes:

 Any endpoint grandchild node may specify a desired video interface

 according to ../../media/video-interfaces.txt, specifically

 - bus-width: recognized values are <12>, <16>, <18> and <24>, and

   override any output mode selection heuristic, forcing "rgb444",

   "rgb565", "rgb666" and "rgb888" respectively.

Example:

	hlcdc: hlcdc@f0030000 {

		compatible = "atmel,sama5d3-hlcdc";

		reg = <0xf0030000 0x2000>;

		interrupts = <36 IRQ_TYPE_LEVEL_HIGH 0>;

		clocks = <&lcdc_clk>, <&lcdck>, <&clk32k>;

		clock-names = "periph_clk","sys_clk", "slow_clk";

		hlcdc-display-controller {

			compatible = "atmel,hlcdc-display-controller";

			pinctrl-names = "default";

			pinctrl-0 = <&pinctrl_lcd_base &pinctrl_lcd_rgb888>;

			#address-cells = <1>;

			#size-cells = <0>;

			port@0 {

				#address-cells = <1>;

				#size-cells = <0>;

				reg = <0>;

				hlcdc_panel_output: endpoint@0 {

					reg = <0>;

					remote-endpoint = <&panel_input>;

				};

			};

		};

		hlcdc_pwm: hlcdc-pwm {

			compatible = "atmel,hlcdc-pwm";

			pinctrl-names = "default";

			pinctrl-0 = <&pinctrl_lcd_pwm>;

			#pwm-cells = <3>;

		};

	};

Example 2: With a video interface override to force rgb565; as above

but with these changes/additions:

	&hlcdc {

		hlcdc-display-controller {

			pinctrl-names = "default";

			pinctrl-0 = <&pinctrl_lcd_base &pinctrl_lcd_rgb565>;

			port@0 {

				hlcdc_panel_output: endpoint@0 {

					bus-width = <16>;

				};

			};

		};

	};