From 4266129964b8238526936d723de65b419d8069c6 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 31 May 2011 16:27:44 -0300 Subject: [media] DocBook: Move all media docbook stuff into its own directory This patch addresses several issues pointed by Randy Dunlap at changeset ece722c: - In the generated index.html file, "media" is listed first, but it should be listed in alphabetical order, not first. - The generated files are (hidden) in .tmpmedia/ - The link from the top-level index.html file to "media" is to media/index.html, but the file is actually in .tmpmedia/media/index.html - Please build docs with and without using "O=builddir" and test that. - Would it be possible for media to have its own Makefile instead of merging into this one? Due to the way cleandocs target works, I had to rename the media DocBook to media_api, otherwise cleandocs would remove the /media directory. Thanks-to: Randy Dunlap Signed-off-by: Mauro Carvalho Chehab --- Documentation/DocBook/media/v4l/dev-event.xml | 31 +++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 Documentation/DocBook/media/v4l/dev-event.xml (limited to 'Documentation/DocBook/media/v4l/dev-event.xml') diff --git a/Documentation/DocBook/media/v4l/dev-event.xml b/Documentation/DocBook/media/v4l/dev-event.xml new file mode 100644 index 000000000000..be5a98fb4fab --- /dev/null +++ b/Documentation/DocBook/media/v4l/dev-event.xml @@ -0,0 +1,31 @@ + Event Interface + + The V4L2 event interface provides means for 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. + + + To receive events, the events the user is interested in first must + be subscribed using the &VIDIOC-SUBSCRIBE-EVENT; ioctl. Once an event is + subscribed, the events of subscribed types are dequeueable using the + &VIDIOC-DQEVENT; ioctl. Events may be unsubscribed using + VIDIOC_UNSUBSCRIBE_EVENT ioctl. The special event type V4L2_EVENT_ALL may + be used to unsubscribe all the events the driver supports. + + The event subscriptions and event queues are specific to file + handles. Subscribing an event on one file handle does not affect + 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. + + -- cgit v1.2.3