[PATCH v4 2/4] dt-bindings: media: i2c: Add bindings for IMI RDACM20

[Kieran Bingham]

From: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>

The IMI RDACM20 is a Gigabit Multimedia Serial Link (GMSL) camera
capable of transmitting video and I2C control messages on a coax cable
physical link for automotive applications.

Document its device tree binding interface.

Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

---
v2:
 - Provide imi vendor prefix
 - Fix minor spelling

v3:
 - update binding descriptions
---
 .../bindings/media/i2c/imi,rdacm20.txt        | 65 +++++++++++++++++++
 .../devicetree/bindings/vendor-prefixes.txt   |  1 +
 2 files changed, 66 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/media/i2c/imi,rdacm20.txt

diff --git a/Documentation/devicetree/bindings/media/i2c/imi,rdacm20.txt b/Documentation/devicetree/bindings/media/i2c/imi,rdacm20.txt
new file mode 100644
index 000000000000..23915da4c3bf
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/i2c/imi,rdacm20.txt
@@ -0,0 +1,65 @@
+IMI D&D RDACM20 Automotive Camera Platform
+------------------------------------------
+
+The IMI D&D RDACM20 is a GMSL-compatible camera designed for automotive
+applications. It encloses a Maxim Integrated MAX9271 GMSL serializer, an
+Omnivision OV10635 camera sensor and an embedded MCU, and connects to a remote
+GMSL endpoint through a coaxial cable.
+
+                                                     IMI RDACM20
+ ---------------                               --------------------------------
+|      GMSL     |   <---  Video Stream        |       <- Video--------\        |
+|               |< ====== GMSL Link ======== >|MAX9271<- I2C bus-> <-->OV10635 |
+| de-serializer |   <---  I2C messages --->   |                   \<-->MCU     |
+ ---------------                               --------------------------------
+
+The RDACM20 transmits video data generated by the embedded camera sensor on the
+GMSL serial channel to a remote GMSL de-serializer, as well as it receives and
+transmits I2C messages encapsulated in the GMSL bidirectional control channel.
+
+All I2C traffic received on the GMSL link not directed to the serializer is
+propagated on the local I2C bus to the embedded camera sensor and MCU. All
+I2C traffic generated on the local I2C bus not directed to the serializer is
+propagated to the remote de-serializer encapsulated in the GMSL control channel.
+
+The RDACM20 DT node should be a direct child of the GMSL Deserializer's I2C bus
+corresponding to the GMSL link that the camera is attached to.
+
+Required Properties:
+
+- compatible: Shall be "imi,rdacm20".
+- reg: Pair of I2C device addresses, the first to be assigned to the serializer
+  the second to be assigned to the camera sensor.
+
+Connection to the remote GMSL endpoint are modelled using the OF graph bindings
+in accordance with the video interface bindings defined in
+Documentation/devicetree/bindings/media/video-interfaces.txt.
+
+The device node contains a single "port" child node with a single "endpoint"
+sub-device.
+
+Required endpoint properties:
+
+- remote-endpoint: phandle to the remote GMSL endpoint sub-node in the remote
+  node port.
+
+Example:
+-------
+
+	i2c@0 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		reg = <0>;
+
+		camera@51 {
+			compatible = "imi,rdacm20";
+			reg = <0x51 0x61>;
+
+			port {
+				rdacm20_out0: endpoint {
+					remote-endpoint = <&max9286_in0>;
+				};
+			};
+
+		};
+	};
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 2c3fc512e746..34b0ed876850 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -171,6 +171,7 @@ idt	Integrated Device Technologies, Inc.
 ifi	Ingenieurburo Fur Ic-Technologie (I/F/I)
 ilitek	ILI Technology Corporation (ILITEK)
 img	Imagination Technologies Ltd.
+imi	Integrated Micro-Electronics Inc.
 infineon Infineon Technologies
 inforce	Inforce Computing
 ingenic	Ingenic Semiconductor
-- 
2.17.1