mcd_getqchan
if (mcd_getqchan(sc, &q, CD_TRACK_INFO) != 0)
if ((error = mcd_getqchan(sc, &q, ch->data_format)) != 0)
if ((error = mcd_getqchan(sc, &q, CD_CURRENT_POSITION)) != 0)
int mcd_getqchan(struct mcd_softc *, union mcd_qchninfo *, int);