dt-bindings: extcon: Add support for cros-ec device

This patch add documentation for binding of USB Type C cable detection
mechanism is using EXTCON subsystem. The device can detect the presence
of display out but it may also detect other external accessories when
external accessories is attached or detached.

Signed-off-by: Benson Leung <[email protected]>
Signed-off-by: Enric Balletbo i Serra <[email protected]>
Reviewed-by: Chanwoo Choi <[email protected]>
Acked-by: Rob Herring <[email protected]>
Signed-off-by: Chanwoo Choi <[email protected]>

1 files changed, 24 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/extcon/extcon-usbc-cros-ec.txt b/Documentation/devicetree/bindings/extcon/extcon-usbc-cros-ec.txt
new file mode 100644
index 000000000000..8e8625c00dfa
--- /dev/null
+++ b/Documentation/devicetree/bindings/extcon/extcon-usbc-cros-ec.txt
@@ -0,0 +1,24 @@
+ChromeOS EC USB Type-C cable and accessories detection
+
+On ChromeOS systems with USB Type C ports, the ChromeOS Embedded Controller is
+able to detect the state of external accessories such as display adapters
+or USB devices when said accessories are attached or detached.
+
+The node for this device must be under a cros-ec node like google,cros-ec-spi
+or google,cros-ec-i2c.
+
+Required properties:
+- compatible:		Should be "google,extcon-usbc-cros-ec".
+- google,usb-port-id:	Specifies the USB port ID to use.
+
+Example:
+	cros-ec@0 {
+		compatible = "google,cros-ec-i2c";
+
+		...
+
+		extcon {
+			compatible = "google,extcon-usbc-cros-ec";
+			google,usb-port-id = <0>;
+		};
+	}