Host Controller Registration

Whenever the USB configuration method is run, it opens the USBD special file (/dev/usb0) and attempts to register each detected and available USB host controller with the USB System Driver through a USBD_REGISTER_HC IOCTL.

During the processing of the USBD_REGISTER_HC IOCTL, the USBD opens the host controller driver and requests for the registration of call vectors that are stored with in the Host controller driver through a HCD_REGISTER_HC IOCTL. After the call vectors are registered with the USBD, the USB System Driver (USBD) and the Host controller driver communicates through the call vectors.