dt-bindings: display: Add Allwinner MIPI-DSI bindings

The Allwinner SoCs usually come with a DSI encoder. Add a binding for it.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/cdc5402570199f5c08211f29d9182ea5948d3c40.1522835818.git-series.maxime.ripard@bootlin.com

Documentation/devicetree/bindings/display/sunxi/sun6i-dsi.txt

+Allwinner A31 DSI Encoder
+=========================
+
+The DSI pipeline consists of two separate blocks: the DSI controller
+itself, and its associated D-PHY.
+
+DSI Encoder
+-----------
+
+The DSI Encoder generates the DSI signal from the TCON's.
+
+Required properties:
+  - compatible: value must be one of:
+    * allwinner,sun6i-a31-mipi-dsi
+  - reg: base address and size of memory-mapped region
+  - interrupts: interrupt associated to this IP
+  - clocks: phandles to the clocks feeding the DSI encoder
+    * bus: the DSI interface clock
+    * mod: the DSI module clock
+  - clock-names: the clock names mentioned above
+  - phys: phandle to the D-PHY
+  - phy-names: must be "dphy"
+  - resets: phandle to the reset controller driving the encoder
+
+  - ports: A ports node with endpoint definitions as defined in
+    Documentation/devicetree/bindings/media/video-interfaces.txt. The
+    first port should be the input endpoint, usually coming from the
+    associated TCON.
+
+Any MIPI-DSI device attached to this should be described according to
+the bindings defined in ../mipi-dsi-bus.txt
+
+D-PHY
+-----
+
+Required properties:
+  - compatible: value must be one of:
+    * allwinner,sun6i-a31-mipi-dphy
+  - reg: base address and size of memory-mapped region
+  - clocks: phandles to the clocks feeding the DSI encoder
+    * bus: the DSI interface clock
+    * mod: the DSI module clock
+  - clock-names: the clock names mentioned above
+  - resets: phandle to the reset controller driving the encoder
+
+Example:
+
+dsi0: dsi@1ca0000 {
+	compatible = "allwinner,sun6i-a31-mipi-dsi";
+	reg = <0x01ca0000 0x1000>;
+	interrupts = <GIC_SPI 89 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&ccu CLK_BUS_MIPI_DSI>,
+		 <&ccu CLK_DSI_SCLK>;
+	clock-names = "bus", "mod";
+	resets = <&ccu RST_BUS_MIPI_DSI>;
+	phys = <&dphy0>;
+	phy-names = "dphy";
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	panel@0 {
+		compatible = "bananapi,lhr050h41", "ilitek,ili9881c";
+		reg = <0>;
+		power-gpios = <&pio 1 7 GPIO_ACTIVE_HIGH>; /* PB07 */
+		reset-gpios = <&r_pio 0 5 GPIO_ACTIVE_LOW>; /* PL05 */
+		backlight = <&pwm_bl>;
+	};
+
+	ports {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		port@0 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <0>;
+
+			dsi0_in_tcon0: endpoint {
+				remote-endpoint = <&tcon0_out_dsi0>;
+			};
+		};
+	};
+};
+
+dphy0: d-phy@1ca1000 {
+	compatible = "allwinner,sun6i-a31-mipi-dphy";
+	reg = <0x01ca1000 0x1000>;
+	clocks = <&ccu CLK_BUS_MIPI_DSI>,
+		 <&ccu CLK_DSI_DPHY>;
+	clock-names = "bus", "mod";
+	resets = <&ccu RST_BUS_MIPI_DSI>;
+	#phy-cells = <0>;
+};