[PATCH v7 2/8] drm/sun8i: Add DT bindings documentation of Allwinner DE2

[laurent.pinchart@ideasonboard.com (Laurent Pinchart)]

Hi Jean-Fran?ois,

Thank you for the patch.

On Monday 28 Nov 2016 19:02:39 Jean-Francois Moine wrote:
> Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
> ---
>  .../bindings/display/sunxi/sun8i-de2.txt           | 121 ++++++++++++++++++
>  1 file changed, 121 insertions(+)
>  create mode 100644
> Documentation/devicetree/bindings/display/sunxi/sun8i-de2.txt
> 
> diff --git a/Documentation/devicetree/bindings/display/sunxi/sun8i-de2.txt
> b/Documentation/devicetree/bindings/display/sunxi/sun8i-de2.txt new file
> mode 100644
> index 0000000..edf38b8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/sunxi/sun8i-de2.txt
> @@ -0,0 +1,121 @@
> +Allwinner sun8i Display Engine 2 subsystem
> +==========================================
> +
> +The Allwinner DE2 subsystem contains a display controller (DE2),
> +one or two LCD controllers (Timing CONtrollers) and their external
> +interfaces (encoders/connectors).
> +
> +          +-----------+
> +          | DE2       |
> +          |           |
> +          | +-------+ |
> +  plane --->|       | |   +------+
> +          | | mixer |---->| TCON |---> encoder  ---> display
> +  plane --->|       | |   +------+     connector     device
> +          | +-------+ |
> +          |           |
> +          | +-------+ |
> +  plane --->|       | |   +------+
> +          | | mixer |---->| TCON |---> encoder  ---> display
> +  plane --->|       | |   +------+     connector     device
> +          | +-------+ |
> +          +-----------+
> +
> +The DE2 contains a processor which mixes the input planes and creates
> +the images which are sent to the TCONs.
> +From the software point of vue, there are 2 independent real-time
> +mixers, each one being statically associated to one TCON.
> +
> +The TCONs adjust the image format to the one of the display device.
> +
> +Display controller (DE2)
> +========================
> +
> +Required properties:
> +
> +- compatible: value should be one of the following
> +		"allwinner,sun8i-a83t-display-engine"
> +		"allwinner,sun8i-h3-display-engine"
> +
> +- reg: base address and size of the I/O memory
> +
> +- clocks: must include clock specifiers corresponding to entries in the
> +		clock-names property.
> +
> +- clock-names: must contain
> +		"bus": bus gate
> +		"clock": clock
> +
> +- resets: phandle to the reset of the device
> +
> +- ports: must contain a list of 2 phandles, indexed by mixer number,
> +	and pointing to display interface ports of TCONs
> +
> +LCD controller (TCON)
> +=====================
> +
> +Required properties:
> +
> +- compatible: should be
> +		"allwinner,sun8i-a83t-tcon"
> +
> +- reg: base address and size of the I/O memory
> +
> +- clocks: must include clock specifiers corresponding to entries in the
> +		clock-names property.
> +
> +- clock-names: must contain
> +		"bus": bus gate
> +		"clock": pixel clock
> +
> +- resets: phandle to the reset of the device
> +
> +- interrupts: interrupt number for the TCON
> +
> +- port: port node with endpoint definitions as defined in
> +	Documentation/devicetree/bindings/media/video-interfaces.txt
> +
> +Example:
> +
> +	de: de-controller at 01000000 {
> +		compatible = "allwinner,sun8i-h3-display-engine";
> +		reg = <0x01000000 0x400000>;
> +		clocks = <&ccu CLK_BUS_DE>, <&ccu CLK_DE>;
> +		clock-names = "bus", "clock";
> +		resets = <&ccu RST_BUS_DE>;
> +		ports = <&tcon0_p>, <&tcon1_p>;

This isn't how the OF graph DT bindings are used. You should instead have

	ports {
		#address-cells = <1>;
		#size-cells = <0>;
		port at 0 {
			de_out_0: endpoint {
				remote_endpoint = <&tcon0_hdmi>;
			};
		};
		port at 1 {
			/* No endpoint as the port is not connected */
		};
	};

> +	};
> +
> +	tcon0: lcd-controller at 01c0c000 {
> +		compatible = "allwinner,sun8i-a83t-tcon";
> +		reg = <0x01c0c000 0x400>;
> +		clocks = <&ccu CLK_BUS_TCON0>, <&ccu CLK_TCON0>;
> +		clock-names = "bus", "clock";
> +		resets = <&ccu RST_BUS_TCON0>;
> +		interrupts = <GIC_SPI 86 IRQ_TYPE_LEVEL_HIGH>;
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +		tcon0_p: port {
> +			tcon0_hdmi: endpoint {
> +				remote-endpoint = <&hdmi_tcon0>;
> +			};
> +		};

and here

	port {
		tcon0_hdmi: endpoint {
			remote-endpoint = <&de_out_0>;
		};
	};

> +	};
> +
> +	/* not used */
> +	tcon1: lcd-controller at 01c0d000 {
> +		compatible = "allwinner,sun8i-h3-tcon";
> +		reg = <0x01c0d000 0x400>;
> +		clocks = <&ccu CLK_BUS_TCON1>,
> +			 <&ccu CLK_TCON0>;	/* no clock */
> +		clock-names = "bus", "clock";
> +		interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
> +		status = "disabled";
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +		tcon1_p: port {
> +			endpoint {
> +				/* empty */
> +			};
> +		};

and here

	port {
		/* No endpoint as the port is not connected */
	};

(although I'm not sure why you don't connect it)

> +	};

-- 
Regards,

Laurent Pinchart