diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt
index 6c4866b49eb57..ae3a2cc4f3ed3 100644
--- a/Documentation/video4linux/v4l2-framework.txt
+++ b/Documentation/video4linux/v4l2-framework.txt
@@ -768,6 +768,7 @@ types exist:
 VFL_TYPE_GRABBER: videoX for video input/output devices
 VFL_TYPE_VBI: vbiX for vertical blank data (i.e. closed captions, teletext)
 VFL_TYPE_RADIO: radioX for radio tuners
+VFL_TYPE_SDR: swradioX for Software Defined Radio tuners
 
 The last argument gives you a certain amount of control over the device
 device node number used (i.e. the X in videoX). Normally you will pass -1