#include <dc1394/juju/firewire-cdev.h>
Add a descriptor block and optionally a preceding immediate key to the local node's configuration ROM.
The field specifies the upper 8 bits of the descriptor root directory pointer and the and fields specify the contents. The should be of the form 0xXX000000. The offset part of the root directory entry will be filled in by the kernel.
If not 0, the field specifies an immediate key which will be inserted before the root directory pointer.
If successful, the kernel adds the descriptor and writes back a handle to the kernel-side object to be used for later removal of the descriptor block and immediate key.