Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 205 insertions, 0 deletions

diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h
new file mode 100644
index 000000000..17833e886
--- /dev/null
+++ b/include/media/v4l2-event.h
@@ -0,0 +1,205 @@
+/*
+ * v4l2-event.h
+ *
+ * V4L2 events.
+ *
+ * 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
+#define V4L2_EVENT_H
+
+#include <linux/types.h>
+#include <linux/videodev2.h>
+#include <linux/wait.h>
+
+struct v4l2_fh;
+struct v4l2_subdev;
+struct v4l2_subscribed_event;
+struct video_device;
+
+/**
+ * struct v4l2_kevent - Internal kernel event struct.
+ * @list:	List node for the v4l2_fh->available list.
+ * @sev:	Pointer to parent v4l2_subscribed_event.
+ * @event:	The event itself.
+ */
+struct v4l2_kevent {
+	struct list_head	list;
+	struct v4l2_subscribed_event *sev;
+	struct v4l2_event	event;
+};
+
+/**
+ * struct v4l2_subscribed_event_ops - Subscribed event operations.
+ *
+ * @add:	Optional callback, called when a new listener is added
+ * @del:	Optional callback, called when a listener stops listening
+ * @replace:	Optional callback that can replace event 'old' with event 'new'.
+ * @merge:	Optional callback that can merge event 'old' into event 'new'.
+ */
+struct v4l2_subscribed_event_ops {
+	int  (*add)(struct v4l2_subscribed_event *sev, unsigned int elems);
+	void (*del)(struct v4l2_subscribed_event *sev);
+	void (*replace)(struct v4l2_event *old, const struct v4l2_event *new);
+	void (*merge)(const struct v4l2_event *old, struct v4l2_event *new);
+};
+
+/**
+ * struct v4l2_subscribed_event - Internal struct representing a subscribed
+ *		event.
+ *
+ * @list:	List node for the v4l2_fh->subscribed list.
+ * @type:	Event type.
+ * @id:	Associated object ID (e.g. control ID). 0 if there isn't any.
+ * @flags:	Copy of v4l2_event_subscription->flags.
+ * @fh:	Filehandle that subscribed to this event.
+ * @node:	List node that hooks into the object's event list
+ *		(if there is one).
+ * @ops:	v4l2_subscribed_event_ops
+ * @elems:	The number of elements in the events array.
+ * @first:	The index of the events containing the oldest available event.
+ * @in_use:	The number of queued events.
+ * @events:	An array of @elems events.
+ */
+struct v4l2_subscribed_event {
+	struct list_head	list;
+	u32			type;
+	u32			id;
+	u32			flags;
+	struct v4l2_fh		*fh;
+	struct list_head	node;
+	const struct v4l2_subscribed_event_ops *ops;
+	unsigned int		elems;
+	unsigned int		first;
+	unsigned int		in_use;
+	struct v4l2_kevent	events[];
+};
+
+/**
+ * v4l2_event_dequeue - Dequeue events from video device.
+ *
+ * @fh: pointer to struct v4l2_fh
+ * @event: pointer to struct v4l2_event
+ * @nonblocking: if not zero, waits for an event to arrive
+ */
+int v4l2_event_dequeue(struct v4l2_fh *fh, struct v4l2_event *event,
+		       int nonblocking);
+
+/**
+ * v4l2_event_queue - Queue events to video device.
+ *
+ * @vdev: pointer to &struct video_device
+ * @ev: pointer to &struct v4l2_event
+ *
+ * The event will be queued for all &struct v4l2_fh file handlers.
+ *
+ * .. 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.
+ */
+void v4l2_event_queue(struct video_device *vdev, const struct v4l2_event *ev);
+
+/**
+ * v4l2_event_queue_fh - Queue events to video device.
+ *
+ * @fh: pointer to &struct v4l2_fh
+ * @ev: pointer to &struct v4l2_event
+ *
+ *
+ * The event will be queued only for the specified &struct v4l2_fh file handler.
+ *
+ * .. 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.
+ */
+void v4l2_event_queue_fh(struct v4l2_fh *fh, const struct v4l2_event *ev);
+
+/**
+ * v4l2_event_pending - Check if an event is available
+ *
+ * @fh: pointer to &struct v4l2_fh
+ *
+ * Returns the number of pending events.
+ */
+int v4l2_event_pending(struct v4l2_fh *fh);
+
+/**
+ * v4l2_event_subscribe - Subscribes to an event
+ *
+ * @fh: pointer to &struct v4l2_fh
+ * @sub: pointer to &struct v4l2_event_subscription
+ * @elems: size of the events queue
+ * @ops: pointer to &v4l2_subscribed_event_ops
+ *
+ * .. note::
+ *
+ *    if @elems is zero, the framework will fill in a default value,
+ *    with is currently 1 element.
+ */
+int v4l2_event_subscribe(struct v4l2_fh *fh,
+			 const struct v4l2_event_subscription *sub,
+			 unsigned int elems,
+			 const struct v4l2_subscribed_event_ops *ops);
+/**
+ * v4l2_event_unsubscribe - Unsubscribes to an event
+ *
+ * @fh: pointer to &struct v4l2_fh
+ * @sub: pointer to &struct v4l2_event_subscription
+ */
+int v4l2_event_unsubscribe(struct v4l2_fh *fh,
+			   const struct v4l2_event_subscription *sub);
+/**
+ * v4l2_event_unsubscribe_all - Unsubscribes to all events
+ *
+ * @fh: pointer to &struct v4l2_fh
+ */
+void v4l2_event_unsubscribe_all(struct v4l2_fh *fh);
+
+/**
+ * v4l2_event_subdev_unsubscribe - Subdev variant of v4l2_event_unsubscribe()
+ *
+ * @sd: pointer to &struct v4l2_subdev
+ * @fh: pointer to &struct v4l2_fh
+ * @sub: pointer to &struct v4l2_event_subscription
+ *
+ * .. note::
+ *
+ *	This function should be used for the &struct v4l2_subdev_core_ops
+ *	%unsubscribe_event field.
+ */
+int v4l2_event_subdev_unsubscribe(struct v4l2_subdev *sd,
+				  struct v4l2_fh *fh,
+				  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.
+ *
+ * @fh: pointer to struct v4l2_fh
+ * @sub: pointer to &struct v4l2_event_subscription
+ */
+int v4l2_src_change_event_subscribe(struct v4l2_fh *fh,
+				    const struct v4l2_event_subscription *sub);
+/**
+ * v4l2_src_change_event_subdev_subscribe - Variant of v4l2_event_subscribe(),
+ *	meant to subscribe only events of the type %V4L2_EVENT_SOURCE_CHANGE.
+ *
+ * @sd: pointer to &struct v4l2_subdev
+ * @fh: pointer to &struct v4l2_fh
+ * @sub: pointer to &struct v4l2_event_subscription
+ */
+int v4l2_src_change_event_subdev_subscribe(struct v4l2_subdev *sd,
+					   struct v4l2_fh *fh,
+					   struct v4l2_event_subscription *sub);
+#endif /* V4L2_EVENT_H */