AAU_MAX_XFER
error = bus_dmamap_create(sc->sc_dmat, AAU_MAX_XFER, AAU_MAX_SEGS,
AAU_MAX_XFER, AAU_IO_BOUNDARY, 0, &sc->sc_map_out);
error = bus_dmamap_create(sc->sc_dmat, AAU_MAX_XFER,
AAU_MAX_SEGS, AAU_MAX_XFER, AAU_IO_BOUNDARY, 0,
#define AAU_MAX_SEGS ((AAU_MAX_XFER / PAGE_SIZE) + 1)