diff options
Diffstat (limited to 'include/media/v4l2-event.h')
| -rw-r--r-- | include/media/v4l2-event.h | 63 |
1 files changed, 16 insertions, 47 deletions
diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h index 6741910c3a18..3a0e2588361c 100644 --- a/include/media/v4l2-event.h +++ b/include/media/v4l2-event.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* * v4l2-event.h * @@ -6,15 +7,6 @@ * Copyright (C) 2009--2010 Nokia Corporation. * * Contact: Sakari Ailus <sakari.ailus@iki.fi> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * version 2 as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. */ #ifndef V4L2_EVENT_H @@ -24,40 +16,6 @@ #include <linux/videodev2.h> #include <linux/wait.h> -/* - * Overview: - * - * Events are subscribed per-filehandle. An event specification consists of a - * type and is optionally associated with an object identified through the - * 'id' field. So an event is uniquely identified by the (type, id) tuple. - * - * The v4l2-fh struct has a list of subscribed events. The v4l2_subscribed_event - * struct is added to that list, one for every subscribed event. - * - * Each v4l2_subscribed_event struct ends with an array of v4l2_kevent structs. - * This array (ringbuffer, really) is used to store any events raised by the - * driver. The v4l2_kevent struct links into the 'available' list of the - * v4l2_fh struct so VIDIOC_DQEVENT will know which event to dequeue first. - * - * Finally, if the event subscription is associated with a particular object - * such as a V4L2 control, then that object needs to know about that as well - * so that an event can be raised by that object. So the 'node' field can - * be used to link the v4l2_subscribed_event struct into a list of that - * object. - * - * So to summarize: - * - * struct v4l2_fh has two lists: one of the subscribed events, and one of the - * pending events. - * - * struct v4l2_subscribed_event has a ringbuffer of raised (pending) events of - * that particular type. - * - * If struct v4l2_subscribed_event is associated with a specific object, then - * that object will have an internal list of struct v4l2_subscribed_event so - * it knows who subscribed an event to that object. - */ - struct v4l2_fh; struct v4l2_subdev; struct v4l2_subscribed_event; @@ -68,11 +26,13 @@ struct video_device; * @list: List node for the v4l2_fh->available list. * @sev: Pointer to parent v4l2_subscribed_event. * @event: The event itself. + * @ts: The timestamp of the event. */ struct v4l2_kevent { struct list_head list; struct v4l2_subscribed_event *sev; struct v4l2_event event; + u64 ts; }; /** @@ -118,7 +78,7 @@ struct v4l2_subscribed_event { unsigned int elems; unsigned int first; unsigned int in_use; - struct v4l2_kevent events[]; + struct v4l2_kevent events[] __counted_by(elems); }; /** @@ -141,7 +101,7 @@ int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event, * * .. note:: * The driver's only responsibility is to fill in the type and the data - * fields.The other fields will be filled in by V4L2. + * fields. The other fields will be filled in by V4L2. */ void v4l2_event_queue(struct video_device *vdev, const struct v4l2_event *ev); @@ -156,11 +116,20 @@ void v4l2_event_queue(struct video_device *vdev, const struct v4l2_event *ev); * * .. note:: * The driver's only responsibility is to fill in the type and the data - * fields.The other fields will be filled in by V4L2. + * fields. The other fields will be filled in by V4L2. */ void v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *ev); /** + * v4l2_event_wake_all - Wake all filehandles. + * + * Used when unregistering a video device. + * + * @vdev: pointer to &struct video_device + */ +void v4l2_event_wake_all(struct video_device *vdev); + +/** * v4l2_event_pending - Check if an event is available * * @fh: pointer to &struct v4l2_fh @@ -218,7 +187,7 @@ int v4l2_event_subdev_unsubscribe(struct v4l2_subdev *sd, struct v4l2_event_subscription *sub); /** * v4l2_src_change_event_subscribe - helper function that calls - * v4l2_event_subscribe() if the event is %V4L2_EVENT_SOURCE_CHANGE. + * v4l2_event_subscribe() if the event is %V4L2_EVENT_SOURCE_CHANGE. * * @fh: pointer to struct v4l2_fh * @sub: pointer to &struct v4l2_event_subscription |