IWM_AGG_SSN_TO_TXQ_IDX
idx = IWM_AGG_SSN_TO_TXQ_IDX(ssn);
if (ring->cur != IWM_AGG_SSN_TO_TXQ_IDX(ssn)) {
KASSERT(ring->cur == IWM_AGG_SSN_TO_TXQ_IDX(ssn));
iwm_txq_advance(sc, txq, IWM_AGG_SSN_TO_TXQ_IDX(ssn));
iwm_txq_advance(sc, ring, IWM_AGG_SSN_TO_TXQ_IDX(ssn));
idx = IWM_AGG_SSN_TO_TXQ_IDX(seq);
end_idx = IWM_AGG_SSN_TO_TXQ_IDX(ssn);
iwm_txq_advance(sc, ring, IWM_AGG_SSN_TO_TXQ_IDX(ssn));