diff --git a/Documentation/devicetree/bindings/display/imx/fsl,imx-fb.txt b/Documentation/devicetree/bindings/display/imx/fsl,imx-fb.txt
index 7a5c0e204c8edf031c263a4129966445fdd9d0f9..e5a8b363d82972dc64133b69be7cc190f4470f56 100644
--- a/Documentation/devicetree/bindings/display/imx/fsl,imx-fb.txt
+++ b/Documentation/devicetree/bindings/display/imx/fsl,imx-fb.txt
@@ -13,6 +13,8 @@ Required nodes:
 	Additional, the display node has to define properties:
 	- bits-per-pixel: Bits per pixel
 	- fsl,pcr: LCDC PCR value
+	A display node may optionally define
+	- fsl,aus-mode: boolean to enable AUS mode (only for imx21)
 
 Optional properties:
 - lcd-supply: Regulator for LCD supply voltage.