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;
}
static int
uvc_v4l2_open(struct file *file)
{
struct video_device *vdev = video_devdata(file);
struct uvc_device *uvc = video_get_drvdata(vdev);
struct uvc_file_handle *handle;
int ret;
handle = kzalloc(sizeof(*handle), GFP_KERNEL);
if (handle == NULL)
return -ENOMEM;
ret = v4l2_fh_init(&handle->vfh, vdev);
if (ret < 0)
goto error;
ret = v4l2_event_init(&handle->vfh);
if (ret < 0)
goto error;
ret = v4l2_event_alloc(&handle->vfh, 8);
if (ret < 0)
goto error;
v4l2_fh_add(&handle->vfh);
handle->device = &uvc->video;
file->private_data = &handle->vfh;
uvc_function_connect(uvc);
return 0;
error:
v4l2_fh_exit(&handle->vfh);
return ret;
}
static int subdev_open(struct file *file)
{
struct video_device *vdev = video_devdata(file);
struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev);
struct v4l2_subdev_fh *subdev_fh;
#if defined(CONFIG_MEDIA_CONTROLLER)
struct media_entity *entity = NULL;
#endif
int ret;
if (!sd->initialized)
return -EAGAIN;
subdev_fh = kzalloc(sizeof(*subdev_fh), GFP_KERNEL);
if (subdev_fh == NULL)
return -ENOMEM;
ret = subdev_fh_init(subdev_fh, sd);
if (ret) {
kfree(subdev_fh);
return ret;
}
ret = v4l2_fh_init(&subdev_fh->vfh, vdev);
if (ret)
goto err;
if (sd->flags & V4L2_SUBDEV_FL_HAS_EVENTS) {
ret = v4l2_event_init(&subdev_fh->vfh);
if (ret)
goto err;
ret = v4l2_event_alloc(&subdev_fh->vfh, sd->nevents);
if (ret)
goto err;
}
v4l2_fh_add(&subdev_fh->vfh);
file->private_data = &subdev_fh->vfh;
#if defined(CONFIG_MEDIA_CONTROLLER)
if (sd->v4l2_dev->mdev) {
entity = media_entity_get(&sd->entity);
if (!entity) {
ret = -EBUSY;
goto err;
}
}
#endif
ret = v4l2_subdev_call(sd, file, open, subdev_fh);
if (ret < 0 && ret != -ENOIOCTLCMD)
goto err;
return 0;
err:
#if defined(CONFIG_MEDIA_CONTROLLER)
if (entity)
media_entity_put(entity);
#endif
v4l2_fh_del(&subdev_fh->vfh);
v4l2_fh_exit(&subdev_fh->vfh);
subdev_fh_free(subdev_fh);
kfree(subdev_fh);
return ret;
}
