UBT_HCI_EVENT_COMPL_HEAD_SIZE
evt->header.length = resp_len + UBT_HCI_EVENT_COMPL_HEAD_SIZE;
if (evt->header.length == resp_len + UBT_HCI_EVENT_COMPL_HEAD_SIZE)
datalen = evt->header.length - UBT_HCI_EVENT_COMPL_HEAD_SIZE;
evt->header.length = resp_len + UBT_HCI_EVENT_COMPL_HEAD_SIZE;
evt->header.length == resp_len + UBT_HCI_EVENT_COMPL_HEAD_SIZE)