gpio_softc
if (e = ddi_soft_state_init(&statep, sizeof (struct gpio_softc), 1)) {
struct gpio_softc *softc;
struct gpio_softc *softc = NULL;
struct gpio_softc *softc;
struct gpio_softc *softc = getsoftc(instance);
((struct gpio_softc *)ddi_get_soft_state(statep, (minor)))