Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / media / v4l2-core / v4l2-fh.c

diff --git a/kernel/drivers/media/v4l2-core/v4l2-fh.c b/kernel/drivers/media/v4l2-core/v4l2-fh.c
new file mode 100644 (file)
index 0000000..c97067a
--- /dev/null
+++ b/kernel/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);