ADV_HOST_SCSIID
orig_id = ffs(ADV_INB(adv, ADV_HOST_SCSIID)) - 1;
ADV_OUTB(adv, ADV_HOST_SCSIID, tid);
if (ADV_INB(adv, ADV_HOST_SCSIID) == (0x01 << tid)) {
ADV_OUTB(adv, ADV_HOST_SCSIID, orig_id);