/* * 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);