dma_setup
sc->dma_setup = dma_setup;
int (*dma_setup) (struct edma_softc *, struct tcd_conf *);
sc->edma_sc->dma_setup(sc->edma_sc, sc->tcd);
if (dma_setup(sc))
ch->dma_setup = 0;
ch->dma_setup = 0;
ch->dma_setup = 0;
if (!ch->dma_setup) {
ch->dma_setup = 1;
int dma_setup, dma_active, dma_chan;