/* Ring the door bell to notify XHCI there is a transaction to be executed. */
EFI_STATUS EFIAPI XhcRingDoorBell(IN USB_XHCI_INSTANCE *Xhc, IN UINT8 SlotId, IN UINT8 Dci)
/* Ring the door bell to notify XHCI there is a transaction to be executed. */
EFI_STATUS EFIAPI XhcRingDoorBell(IN USB_XHCI_INSTANCE *Xhc, IN UINT8 SlotId, IN UINT8 Dci)
{
  if (SlotId == 0) {
    XhcWriteDoorBellReg (Xhc, 0, 0);
  } else {
    XhcWriteDoorBellReg (Xhc, SlotId * sizeof (UINT32), Dci);
  }
  return EFI_SUCCESS;
}