Thanks, lesto!

In case anyone's wondering, it's SPI0 that's causing the conflict. Switching it off allows UART2 to work properly.

I'm having the same problem here. UART2 works fine with 3.x kernel, but with 4.11.12 the GPIO pins seem to be misconfigured. This is what they look like: root@NanoPi-NEO2:~# gpio readall +-----+-----+----------+------+---+-NanoPi-NEO2--+------+----------+-----+-----+ | BCM | wPi | Name | Mode | V | ...