From b766586b1a87c5417ee6d1f3806f06ccfc335277 Mon Sep 17 00:00:00 2001 From: Hans Verkuil Date: Wed, 18 Mar 2015 07:05:31 -0300 Subject: [PATCH] [media] DocBook media: improve event documentation It always annoyed me that the event type documentation was separate from the struct v4l2_event documentation. This patch moves it all to one place, VIDIOC_DQEVENT. This makes much more sense. Also changed the 'changes-flags' ref to 'ctrl-changes-flags' since this referred to control changes. There is a src-changes-flags as well, so 'changes-flags' was a bit vague. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/DocBook/media/v4l/compat.xml | 2 +- Documentation/DocBook/media/v4l/vidioc-dqevent.xml | 115 ++++++++++++++++++++- .../DocBook/media/v4l/vidioc-subscribe-event.xml | 111 +------------------- 3 files changed, 115 insertions(+), 113 deletions(-) diff --git a/Documentation/DocBook/media/v4l/compat.xml b/Documentation/DocBook/media/v4l/compat.xml index 350dfb3d71ea..a0aef85d33c1 100644 --- a/Documentation/DocBook/media/v4l/compat.xml +++ b/Documentation/DocBook/media/v4l/compat.xml @@ -2491,7 +2491,7 @@ that used it. It was originally scheduled for removal in 2.6.35. Added V4L2_EVENT_CTRL_CH_RANGE control event - changes flag. See . + changes flag. See . diff --git a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml b/Documentation/DocBook/media/v4l/vidioc-dqevent.xml index b036f8963353..a31eea07d455 100644 --- a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml +++ b/Documentation/DocBook/media/v4l/vidioc-dqevent.xml @@ -64,7 +64,7 @@ __u32 type - Type of the event. + Type of the event, see . union @@ -154,6 +154,113 @@ + + Event Types + + &cs-def; + + + V4L2_EVENT_ALL + 0 + All events. V4L2_EVENT_ALL is valid only for + VIDIOC_UNSUBSCRIBE_EVENT for unsubscribing all events at once. + + + + V4L2_EVENT_VSYNC + 1 + This event is triggered on the vertical sync. + This event has a &v4l2-event-vsync; associated with it. + + + + V4L2_EVENT_EOS + 2 + This event is triggered when the end of a stream is reached. + This is typically used with MPEG decoders to report to the application + when the last of the MPEG stream has been decoded. + + + + V4L2_EVENT_CTRL + 3 + This event requires that the id + matches the control ID from which you want to receive events. + This event is triggered if the control's value changes, if a + button control is pressed or if the control's flags change. + This event has a &v4l2-event-ctrl; associated with it. This struct + contains much of the same information as &v4l2-queryctrl; and + &v4l2-control;. + + If the event is generated due to a call to &VIDIOC-S-CTRL; or + &VIDIOC-S-EXT-CTRLS;, then the event will not be sent to + the file handle that called the ioctl function. This prevents + nasty feedback loops. If you do want to get the + event, then set the V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK + flag. + + + This event type will ensure that no information is lost when + more events are raised than there is room internally. In that + case the &v4l2-event-ctrl; of the second-oldest event is kept, + but the changes field of the + second-oldest event is ORed with the changes + field of the oldest event. + + + + V4L2_EVENT_FRAME_SYNC + 4 + + Triggered immediately when the reception of a + frame has begun. This event has a + &v4l2-event-frame-sync; associated with it. + + If the hardware needs to be stopped in the case of a + buffer underrun it might not be able to generate this event. + In such cases the frame_sequence + field in &v4l2-event-frame-sync; will not be incremented. This + causes two consecutive frame sequence numbers to have n times + frame interval in between them. + + + + V4L2_EVENT_SOURCE_CHANGE + 5 + + This event is triggered when a source parameter change is + detected during runtime by the video device. It can be a + runtime resolution change triggered by a video decoder or the + format change happening on an input connector. + This event requires that the id + matches the input index (when used with a video device node) + or the pad index (when used with a subdevice node) from which + you want to receive events. + + This event has a &v4l2-event-src-change; associated + with it. The changes bitfield denotes + what has changed for the subscribed pad. If multiple events + occurred before application could dequeue them, then the changes + will have the ORed value of all the events generated. + + + + V4L2_EVENT_MOTION_DET + 6 + + Triggered whenever the motion detection state for one or more of the regions + changes. This event has a &v4l2-event-motion-det; associated with it. + + + + V4L2_EVENT_PRIVATE_START + 0x08000000 + Base event number for driver-private events. + + + +
+ struct <structname>v4l2_event_vsync</structname> @@ -177,7 +284,7 @@ __u32 changes - A bitmask that tells what has changed. See . + A bitmask that tells what has changed. See . __u32 @@ -309,8 +416,8 @@
- - Changes +
+ Control Changes &cs-def; diff --git a/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml b/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml index d7c9365ecdbe..d0332f610929 100644 --- a/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml +++ b/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml @@ -60,7 +60,9 @@ __u32 type - Type of the event. + Type of the event, see . Note that +V4L2_EVENT_ALL can be used with VIDIOC_UNSUBSCRIBE_EVENT +for unsubscribing all events at once. __u32 @@ -84,113 +86,6 @@
- - Event Types - - &cs-def; - - - V4L2_EVENT_ALL - 0 - All events. V4L2_EVENT_ALL is valid only for - VIDIOC_UNSUBSCRIBE_EVENT for unsubscribing all events at once. - - - - V4L2_EVENT_VSYNC - 1 - This event is triggered on the vertical sync. - This event has a &v4l2-event-vsync; associated with it. - - - - V4L2_EVENT_EOS - 2 - This event is triggered when the end of a stream is reached. - This is typically used with MPEG decoders to report to the application - when the last of the MPEG stream has been decoded. - - - - V4L2_EVENT_CTRL - 3 - This event requires that the id - matches the control ID from which you want to receive events. - This event is triggered if the control's value changes, if a - button control is pressed or if the control's flags change. - This event has a &v4l2-event-ctrl; associated with it. This struct - contains much of the same information as &v4l2-queryctrl; and - &v4l2-control;. - - If the event is generated due to a call to &VIDIOC-S-CTRL; or - &VIDIOC-S-EXT-CTRLS;, then the event will not be sent to - the file handle that called the ioctl function. This prevents - nasty feedback loops. If you do want to get the - event, then set the V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK - flag. - - - This event type will ensure that no information is lost when - more events are raised than there is room internally. In that - case the &v4l2-event-ctrl; of the second-oldest event is kept, - but the changes field of the - second-oldest event is ORed with the changes - field of the oldest event. - - - - V4L2_EVENT_FRAME_SYNC - 4 - - Triggered immediately when the reception of a - frame has begun. This event has a - &v4l2-event-frame-sync; associated with it. - - If the hardware needs to be stopped in the case of a - buffer underrun it might not be able to generate this event. - In such cases the frame_sequence - field in &v4l2-event-frame-sync; will not be incremented. This - causes two consecutive frame sequence numbers to have n times - frame interval in between them. - - - - V4L2_EVENT_SOURCE_CHANGE - 5 - - This event is triggered when a source parameter change is - detected during runtime by the video device. It can be a - runtime resolution change triggered by a video decoder or the - format change happening on an input connector. - This event requires that the id - matches the input index (when used with a video device node) - or the pad index (when used with a subdevice node) from which - you want to receive events. - - This event has a &v4l2-event-src-change; associated - with it. The changes bitfield denotes - what has changed for the subscribed pad. If multiple events - occurred before application could dequeue them, then the changes - will have the ORed value of all the events generated. - - - - V4L2_EVENT_MOTION_DET - 6 - - Triggered whenever the motion detection state for one or more of the regions - changes. This event has a &v4l2-event-motion-det; associated with it. - - - - V4L2_EVENT_PRIVATE_START - 0x08000000 - Base event number for driver-private events. - - - -
- Event Flags -- 2.11.0