drm/bridge: Add sii902x DT bindings doc

Add Sii9022 DT bindings description.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
---
Changes since v6:
- make 'reset-gpios' optional

Changes since v1:
- rename doc file
- s/sil902/sii902/

diff --git a/Documentation/devicetree/bindings/display/bridge/sii902x.txt b/Documentation/devicetree/bindings/display/bridge/sii902x.txt
new file mode 100644 (file)
index 0000000..56a3e68
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt
@@ -0,0 +1,35 @@
+sii902x HDMI bridge bindings
+
+Required properties:
+       - compatible: "sil,sii9022"
+       - reg: i2c address of the bridge
+
+Optional properties:
+       - interrupts-extended or interrupt-parent + interrupts: describe
+         the interrupt line used to inform the host about hotplug events.
+       - reset-gpios: OF device-tree gpio specification for RST_N pin.
+
+Optional subnodes:
+       - video input: this subnode can contain a video input port node
+         to connect the bridge to a display controller output (See this
+         documentation [1]).
+
+[1]: Documentation/devicetree/bindings/media/video-interfaces.txt
+
+Example:
+       hdmi-bridge@39 {
+               compatible = "sil,sii9022";
+               reg = <0x39>;
+               reset-gpios = <&pioA 1 0>;
+               ports {
+                       #address-cells = <1>;
+                       #size-cells = <0>;
+
+                       port@0 {
+                               reg = <0>;
+                               bridge_in: endpoint {
+                                       remote-endpoint = <&dc_out>;
+                               };
+                       };
+               };
+       };