static ssize_t pwc_video_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct pwc_device *pdev = video_drvdata(file);
if (!pdev->udev)
return -ENODEV;
if (pwc_test_n_set_capt_file(pdev, file))
return -EBUSY;
return vb2_read(&pdev->vb_queue, buf, count, ppos,
file->f_flags & O_NONBLOCK);
}
ssize_t vb2_fop_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
struct video_device *vdev = video_devdata(file);
struct mutex *lock = vdev->queue->lock ? vdev->queue->lock : vdev->lock;
int err = -EBUSY;
if (!(vdev->queue->io_modes & VB2_READ))
return -EINVAL;
if (lock && mutex_lock_interruptible(lock))
return -ERESTARTSYS;
if (vb2_queue_is_busy(vdev, file))
goto exit;
err = vb2_read(vdev->queue, buf, count, ppos,
file->f_flags & O_NONBLOCK);
if (vdev->queue->fileio)
vdev->queue->owner = file->private_data;
exit:
if (lock)
mutex_unlock(lock);
return err;
}