Hi, > Are you saying that once you export these gpios the uart stops working? I'm sorry, I wasn't clear. Only exporting GPIO 3 disables UART. Exporting 85-88 causes reboot. And I have no info about 0-2 (it just most of gpio-reserved-ranges diables 0-3). Therefore probably only <85 4> should go to gpio-reserved-ranges. I'll send v2. Kind regards, Petr > We use gpio-reserved-ranges to denote GPIOs that are owned by TZ, so > touching their registers causes the device to reboot. And per the > gpiolib patch you reference, this would happen as we register the > gpiochip. > It sounds instead like what you want is to make sure that these pins are > considered busy, muxing in the uart (i.e define a state for uart). > Regards, > Bjorn