pxa2x0_i2s_start_output
int pxa2x0_i2s_start_output(void *, void *, int, void (*)(void *), void *);
rv = pxa2x0_i2s_start_output(&sc->sc_i2s, block, bsize, intr, intrarg);
rv = pxa2x0_i2s_start_output(&sc->sc_i2s, block, bsize, intr, intrarg);