I'm unable to see USB devices connected to the internal USB headers on
a PC Engines APU2c2 board. The same devices work as expected when
connected to the external USB ports.
I have a TinyCore Linux USB stick handy that I used to update the
board's firmware. If I boot it and run `lsusb` then I can see my
devices using all of the internal and external USB headers/ports.
So it would seem that the internal headers are wired up and working,
but for some reason I can't use them via ehci. Note that the external
USB ports are USB3, so devices appear via xhci. It could therefore be
a wider issue with ehci on this board.
Install OpenBSD 6.0 on a PC Engines APU2c2 board. Connect a supported
USB 2.0 device to the internal J11 header, using pins 1,3,5,7 or 2,4,6,8
as described on p6 of the APU2c schematic available at the following