diff options
Diffstat (limited to 'Documentation/video4linux')
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 5155700..5b9205a 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -545,12 +545,11 @@ unregister them: This will remove the device nodes from sysfs (causing udev to remove them from /dev). -After video_unregister_device() returns no new opens can be done. - -However, in the case of USB devices some application might still have one -of these device nodes open. You should block all new accesses to read, -write, poll, etc. except possibly for certain ioctl operations like -queueing buffers. +After video_unregister_device() returns no new opens can be done. However, +in the case of USB devices some application might still have one of these +device nodes open. So after the unregister all file operations will return +an error as well, except for the ioctl and unlocked_ioctl file operations: +those will still be passed on since some buffer ioctls may still be needed. When the last user of the video device node exits, then the vdev->release() callback is called and you can do the final cleanup there. |