Initial import

1 files changed, 125 insertions, 0 deletions

diff --git a/drivers/media/v4l2-core/v4l2-fh.c b/drivers/media/v4l2-core/v4l2-fh.c
new file mode 100644
index 000000000..c97067a25
--- /dev/null
+++ b/drivers/media/v4l2-core/v4l2-fh.c
@@ -0,0 +1,125 @@
+/*
+ * v4l2-fh.c
+ *
+ * V4L2 file handles.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/bitops.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ioctl.h>
+
+void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
+{
+	fh->vdev = vdev;
+	/* Inherit from video_device. May be overridden by the driver. */
+	fh->ctrl_handler = vdev->ctrl_handler;
+	INIT_LIST_HEAD(&fh->list);
+	set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
+	/*
+	 * determine_valid_ioctls() does not know if struct v4l2_fh
+	 * is used by this driver, but here we do. So enable the
+	 * prio ioctls here.
+	 */
+	set_bit(_IOC_NR(VIDIOC_G_PRIORITY), vdev->valid_ioctls);
+	set_bit(_IOC_NR(VIDIOC_S_PRIORITY), vdev->valid_ioctls);
+	fh->prio = V4L2_PRIORITY_UNSET;
+	init_waitqueue_head(&fh->wait);
+	INIT_LIST_HEAD(&fh->available);
+	INIT_LIST_HEAD(&fh->subscribed);
+	fh->sequence = -1;
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_init);
+
+void v4l2_fh_add(struct v4l2_fh *fh)
+{
+	unsigned long flags;
+
+	v4l2_prio_open(fh->vdev->prio, &fh->prio);
+	spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+	list_add(&fh->list, &fh->vdev->fh_list);
+	spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_add);
+
+int v4l2_fh_open(struct file *filp)
+{
+	struct video_device *vdev = video_devdata(filp);
+	struct v4l2_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL);
+
+	filp->private_data = fh;
+	if (fh == NULL)
+		return -ENOMEM;
+	v4l2_fh_init(fh, vdev);
+	v4l2_fh_add(fh);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_open);
+
+void v4l2_fh_del(struct v4l2_fh *fh)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+	list_del_init(&fh->list);
+	spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+	v4l2_prio_close(fh->vdev->prio, fh->prio);
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_del);
+
+void v4l2_fh_exit(struct v4l2_fh *fh)
+{
+	if (fh->vdev == NULL)
+		return;
+	v4l2_event_unsubscribe_all(fh);
+	fh->vdev = NULL;
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_exit);
+
+int v4l2_fh_release(struct file *filp)
+{
+	struct v4l2_fh *fh = filp->private_data;
+
+	if (fh) {
+		v4l2_fh_del(fh);
+		v4l2_fh_exit(fh);
+		kfree(fh);
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_release);
+
+int v4l2_fh_is_singular(struct v4l2_fh *fh)
+{
+	unsigned long flags;
+	int is_singular;
+
+	if (fh == NULL || fh->vdev == NULL)
+		return 0;
+	spin_lock_irqsave(&fh->vdev->fh_lock, flags);
+	is_singular = list_is_singular(&fh->list);
+	spin_unlock_irqrestore(&fh->vdev->fh_lock, flags);
+	return is_singular;
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_is_singular);