ath_tx_findrix
an->an_mcastrix = ath_tx_findrix(sc, tp->mcastrate);
an->an_mgmtrix = ath_tx_findrix(sc, tp->mgmtrate);
sc->sc_protrix = ath_tx_findrix(sc, 2*2);
sc->sc_protrix = ath_tx_findrix(sc, 2*1);
extern int ath_tx_findrix(const struct ath_softc *sc, uint8_t rate);
rix = ath_tx_findrix(sc, tp->ucastrate);
rix = ath_tx_findrix(sc, tp->mcastrate);
cix = ath_tx_findrix(sc, bf->bf_state.bfs_ctsrate0);
rix = ath_tx_findrix(sc, params->ibp_rate0);
rix = ath_tx_findrix(sc, params->ibp_rate1);
rix = ath_tx_findrix(sc, params->ibp_rate2);
rix = ath_tx_findrix(sc, params->ibp_rate3);