{
    if(!(SYSCON->AHBCLKCTRL[0] & SYSCON_AHBCLKCTRL_GPIO4(1)))           // CLK already enabled?
    {
        SYSCON->AHBCLKCTRL[2] |= SYSCON_AHBCLKCTRL_GPIO4(1);            // Enable system clock for GPIO4
        SYSCON->PRESETCTRL[2] |= (SYSCON_PRESETCTRL_GPIO4_RST(1));__nop();  // Activate reset
        SYSCON->PRESETCTRL[2] &= ~(SYSCON_PRESETCTRL_GPIO4_RST(1));     // Deactivate reset
    }
    res = (void *) GPIO;
    break;
}