SAGPIO_FER
oldfer = bus_space_read_4(ssp->sc_iot, ssp->sc_gpioh, SAGPIO_FER);
bus_space_write_4(ssp->sc_iot, ssp->sc_gpioh, SAGPIO_FER, 1 << 0);
bus_space_write_4(ssp->sc_iot, ssp->sc_gpioh, SAGPIO_FER, oldfer);
er = bus_space_read_4(ssp->sc_iot, ssp->sc_gpioh, SAGPIO_FER);
bus_space_write_4(ssp->sc_iot, ssp->sc_gpioh, SAGPIO_FER, er);
er = bus_space_read_4(ssp->sc_iot, ssp->sc_gpioh, SAGPIO_FER);
bus_space_write_4(ssp->sc_iot, ssp->sc_gpioh, SAGPIO_FER, er);