[PATCH v4 2/2] dt-bindings: drm/bridge: Document Cadence DSI bridge bindings

[Boris Brezillon]

Document the bindings used for the Cadence DSI bridge.

Signed-off-by: Boris Brezillon <boris.brezillon at free-electrons.com>
---
Hi Rob,

I dropped your A-b because two important things changed in this
version:
* the clk names have changed (they are now prefixed with dsi_)
* compatible no longer contains the IP version

Feel free to add it back.

Regards,

Boris

Changes in v4:
- Rename DSI clks (suggested by Tomi)
- Drop the IP version in the compatible since it can be extracted from
  a register (suggested by Andrzej)

Changes in v3:
- Fix clock names in the example
- Document how to represent DSI devices that are controller through
  an external bus like I2C or SPI

Changes in v2:
- None
---
 .../bindings/display/bridge/cdns,dsi.txt           | 109 +++++++++++++++++++++
 1 file changed, 109 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt

diff --git a/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
new file mode 100644
index 000000000000..50bb3189f2ee
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/cdns,dsi.txt
@@ -0,0 +1,109 @@
+Cadence DSI bridge
+==================
+
+The Cadence DSI bridge is a DPI to DSI bridge supporting up to 4 DSI lanes.
+
+Required properties:
+- compatible: should be set to "cdns,dsi".
+- reg: physical base address and length of the controller's registers.
+- interrupts: interrupt line connected to the DSI bridge.
+- clocks: DSI bridge clocks.
+- clock-names: must contain "dsi_p_clk" and "dsi_sys_clk".
+- phys: phandle link to the MIPI D-PHY controller.
+- phy-names: must contain "dphy".
+- #address-cells: must be set to 1.
+- #size-cells: must be set to 0.
+
+Required subnodes:
+- ports: Ports as described in Documentation/devicetree/bindings/graph.txt.
+  2 ports are available:
+  * port 0: this port is only needed if some of your DSI devices are
+	    controlled through  an external bus like I2C or SPI. Can have at
+	    most 4 endpoints. The endpoint number is directly encoding the
+	    DSI virtual channel used by this device.
+  * port 1: represents the DPI input.
+  Other ports will be added later to support the new kind of inputs.
+
+- one subnode per DSI device connected on the DSI bus. Each DSI device should
+  contain a reg property encoding its virtual channel.
+
+Example:
+
+	dsi0: dsi at fd0c0000 {
+		compatible = "cdns,dsi-1.3.1";
+		reg = <0x0 0xfd0c0000 0x0 0x1000>;
+		clocks = <&pclk>, <&sysclk>;
+		clock-names = "dsi_p_clk", "dsi_sys_clk";
+		interrupts = <1>;
+		phys = <&dphy1>;
+		phy-names = "dphy";
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port at 1 {
+				reg = <1>;
+				dsi0_dpi_input: endpoint {
+					remote-endpoint = <&xxx_dpi_output>;
+				};
+			};
+		};
+
+		panel: dsi-dev at 0 {
+			compatible = "<vendor,panel>";
+			reg = <0>;
+		};
+	};
+
+or
+
+	dsi0: dsi at fd0c0000 {
+		compatible = "cdns,dsi";
+		reg = <0x0 0xfd0c0000 0x0 0x1000>;
+		clocks = <&pclk>, <&sysclk>;
+		clock-names = "sys_p_clk", "dsi_sys_clk";
+		interrupts = <1>;
+		phys = <&dphy1>;
+		phy-names = "dphy";
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port at 0 {
+				reg = <0>;
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				dsi0_output: endpoint at 0 {
+					reg = <0>;
+					remote-endpoint = <&dsi_panel_input>;
+				};
+			};
+
+			port at 1 {
+				reg = <1>;
+				dsi0_dpi_input: endpoint {
+					remote-endpoint = <&xxx_dpi_output>;
+				};
+			};
+		};
+	};
+
+	i2c at xxx {
+		panel: panel at 59 {
+			compatible = "<vendor,panel>";
+			reg = <0x59>;
+
+			port {
+				dsi_panel_input: endpoint {
+					remote-endpoint = <&dsi0_output>;
+				};
+			};
+		};
+	};
-- 
2.11.0