1 files changed, 79 insertions, 0 deletions

diff --git a/drivers/media/video/v4l2-fh.c b/drivers/media/video/v4l2-fh.c
new file mode 100644
index 000000000000..d78f184f40c5
--- /dev/null
+++ b/drivers/media/video/v4l2-fh.c
@@ -0,0 +1,79 @@
+/*
+ * v4l2-fh.c
+ *
+ * V4L2 file handles.
+ *
+ * Copyright (C) 2009--2010 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
+ *
+ * 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 <media/v4l2-dev.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ioctl.h>
+
+int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
+{
+        fh->vdev = vdev;
+        INIT_LIST_HEAD(&fh->list);
+        set_bit(V4L2_FL_USES_V4L2_FH, &fh->vdev->flags);
+
+        /*
+         * fh->events only needs to be initialized if the driver
+         * supports the VIDIOC_SUBSCRIBE_EVENT ioctl.
+         */
+        if (vdev->ioctl_ops && vdev->ioctl_ops->vidioc_subscribe_event)
+                return v4l2_event_init(fh);
+
+        fh->events = NULL;
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_init);
+
+void v4l2_fh_add(struct v4l2_fh *fh)
+{
+        unsigned long flags;
+
+        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);
+
+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);
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_del);
+
+void v4l2_fh_exit(struct v4l2_fh *fh)
+{
+        if (fh->vdev == NULL)
+                return;
+
+        fh->vdev = NULL;
+
+        v4l2_event_free(fh);
+}
+EXPORT_SYMBOL_GPL(v4l2_fh_exit);