diff --git a/Documentation/DocBook/media/v4l/dev-event.xml b/Documentation/DocBook/media/v4l/dev-event.xml
index be5a98fb4fabb2e43c4355142a3216fb79d0407e..f14ae3fe107cf364b8c7d409eb7230f93257a73b 100644
--- a/Documentation/DocBook/media/v4l/dev-event.xml
+++ b/Documentation/DocBook/media/v4l/dev-event.xml
@@ -1,9 +1,10 @@
Event Interface
- The V4L2 event interface provides means for user to get
+ The V4L2 event interface provides a means for a user to get
immediately notified on certain conditions taking place on a device.
This might include start of frame or loss of signal events, for
- example.
+ example. Changes in the value or state of a V4L2 control can also be
+ reported through events.
To receive events, the events the user is interested in first must
@@ -15,12 +16,31 @@
The event subscriptions and event queues are specific to file
handles. Subscribing an event on one file handle does not affect
- other file handles.
-
+ other file handles.
The information on dequeueable events is obtained by using select or
poll system calls on video devices. The V4L2 events use POLLPRI events on
- poll system call and exceptions on select system call.
+ poll system call and exceptions on select system call.
+
+ Starting with kernel 3.1 certain guarantees can be given with
+ regards to events:
+
+ Each subscribed event has its own internal dedicated event queue.
+This means that flooding of one event type will not interfere with other
+event types.
+
+
+ If the internal event queue for a particular subscribed event
+becomes full, then the oldest event in that queue will be dropped.
+
+
+ Where applicable, certain event types can ensure that the payload
+of the oldest event that is about to be dropped will be merged with the payload
+of the next oldest event. Thus ensuring that no information is lost, but only an
+intermediate step leading up to that information. See the documentation for the
+event you want to subscribe to whether this is applicable for that event or not.
+
+