[PATCH v4 2/5] dt-bindings: video: Add for rockchip display subsytem

[Mark yao <mark.yao@rock-chips.com>]

This add a display subsystem comprise the all display interface nodes.

Signed-off-by: Mark Yao <mark.yao@rock-chips.com>
---
Changes in v2:
- add DRM master device node to list all display nodes that comprise
  the graphics subsystem.

Changes in v3: None

Changes in v4: None

 .../devicetree/bindings/video/rockchip-drm.txt     |   19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/video/rockchip-drm.txt

diff --git a/Documentation/devicetree/bindings/video/rockchip-drm.txt b/Documentation/devicetree/bindings/video/rockchip-drm.txt
new file mode 100644
index 0000000..7fff582
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/rockchip-drm.txt
@@ -0,0 +1,19 @@
+Rockchip DRM master device
+================================
+
+The Rockchip DRM master device is a virtual device needed to list all
+vop devices or other display interface nodes that comprise the
+graphics subsystem.
+
+Required properties:
+- compatible: Should be "rockchip,display-subsystem"
+- ports: Should contain a list of phandles pointing to display interface port
+  of vop devices. vop definitions as defined in
+  Documentation/devicetree/bindings/video/rockchip-vop.txt
+
+example:
+
+display-subsystem {
+	compatible = "rockchip,display-subsystem";
+	ports = <&vopl_out>, <&vopb_out>;
+};
-- 
1.7.9.5