devicetree/bindings: display: Add bindings for LVDS panels

LVDS is a physical layer specification defined in ANSI/TIA/EIA-644-A.
Multiple incompatible data link layers have been used over time to
transmit image data to LVDS panels. This binding supports display panels
compatible with the JEIDA-59-1999, Open-LDI and VESA SWPG
specifications.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/display/panel/panel-lvds.txt

@@ -0,0 +1,120 @@
+LVDS Display Panel
+==================
+
+LVDS is a physical layer specification defined in ANSI/TIA/EIA-644-A. Multiple
+incompatible data link layers have been used over time to transmit image data
+to LVDS panels. This bindings supports display panels compatible with the
+following specifications.
+
+[JEIDA] "Digital Interface Standards for Monitor", JEIDA-59-1999, February
+1999 (Version 1.0), Japan Electronic Industry Development Association (JEIDA)
+[LDI] "Open LVDS Display Interface", May 1999 (Version 0.95), National
+Semiconductor
+[VESA] "VESA Notebook Panel Standard", October 2007 (Version 1.0), Video
+Electronics Standards Association (VESA)
+
+Device compatible with those specifications have been marketed under the
+FPD-Link and FlatLink brands.
+
+
+Required properties:
+
+- compatible: Shall contain "panel-lvds" in addition to a mandatory
+  panel-specific compatible string defined in individual panel bindings. The
+  "panel-lvds" value shall never be used on its own.
+- width-mm: See panel-common.txt.
+- height-mm: See panel-common.txt.
+- data-mapping: The color signals mapping order, "jeida-18", "jeida-24"
+  or "vesa-24".
+
+Optional properties:
+
+- label: See panel-common.txt.
+- gpios: See panel-common.txt.
+- backlight: See panel-common.txt.
+- data-mirror: If set, reverse the bit order described in the data mappings
+  below on all data lanes, transmitting bits for slots 6 to 0 instead of
+  0 to 6.
+
+Required nodes:
+
+- panel-timing: See panel-common.txt.
+- ports: See panel-common.txt. These bindings require a single port subnode
+  corresponding to the panel LVDS input.
+
+
+LVDS data mappings are defined as follows.
+
+- "jeida-18" - 18-bit data mapping compatible with the [JEIDA], [LDI] and
+  [VESA] specifications. Data are transferred as follows on 3 LVDS lanes.
+
+Slot	    0       1       2       3       4       5       6
+	________________                         _________________
+Clock	                \_______________________/
+	  ______  ______  ______  ______  ______  ______  ______
+DATA0	><__G0__><__R5__><__R4__><__R3__><__R2__><__R1__><__R0__><
+DATA1	><__B1__><__B0__><__G5__><__G4__><__G3__><__G2__><__G1__><
+DATA2	><_CTL2_><_CTL1_><_CTL0_><__B5__><__B4__><__B3__><__B2__><
+
+- "jeida-24" - 24-bit data mapping compatible with the [DSIM] and [LDI]
+  specifications. Data are transferred as follows on 4 LVDS lanes.
+
+Slot	    0       1       2       3       4       5       6
+	________________                         _________________
+Clock	                \_______________________/
+	  ______  ______  ______  ______  ______  ______  ______
+DATA0	><__G2__><__R7__><__R6__><__R5__><__R4__><__R3__><__R2__><
+DATA1	><__B3__><__B2__><__G7__><__G6__><__G5__><__G4__><__G3__><
+DATA2	><_CTL2_><_CTL1_><_CTL0_><__B7__><__B6__><__B5__><__B4__><
+DATA3	><_CTL3_><__B1__><__B0__><__G1__><__G0__><__R1__><__R0__><
+
+- "vesa-24" - 24-bit data mapping compatible with the [VESA] specification.
+  Data are transferred as follows on 4 LVDS lanes.
+
+Slot	    0       1       2       3       4       5       6
+	________________                         _________________
+Clock	                \_______________________/
+	  ______  ______  ______  ______  ______  ______  ______
+DATA0	><__G0__><__R5__><__R4__><__R3__><__R2__><__R1__><__R0__><
+DATA1	><__B1__><__B0__><__G5__><__G4__><__G3__><__G2__><__G1__><
+DATA2	><_CTL2_><_CTL1_><_CTL0_><__B5__><__B4__><__B3__><__B2__><
+DATA3	><_CTL3_><__B7__><__B6__><__G7__><__G6__><__R7__><__R6__><
+
+Control signals are mapped as follows.
+
+CTL0: HSync
+CTL1: VSync
+CTL2: Data Enable
+CTL3: 0
+
+
+Example
+-------
+
+panel {
+	compatible = "mitsubishi,aa121td01", "panel-lvds";
+
+	width-mm = <261>;
+	height-mm = <163>;
+
+	data-mapping = "jeida-24";
+
+	panel-timing {
+		/* 1280x800 @60Hz */
+		clock-frequency = <71000000>;
+		hactive = <1280>;
+		vactive = <800>;
+		hsync-len = <70>;
+		hfront-porch = <20>;
+		hback-porch = <70>;
+		vsync-len = <5>;
+		vfront-porch = <3>;
+		vback-porch = <15>;
+	};
+
+	port {
+		panel_in: endpoint {
+			remote-endpoint = <&lvds_encoder>;
+		};
+	};
+};