Thanks very much DaneLLL and snarky.
The echo 6 suggestion yields the same result as before, even with the extra sudo flag.
DaneLLL: your link points to pretty much exactly what we’re trying to do: power-cycle the usb hub.
However, the corresponding regulator device on the Nano doesn’t seem to respond to writing to the ‘state’ file as shown here:
root@MA10014:/home/ubuntu# cat /sys/kernel/debug/regulator/vdd-usb-hub-en/regulator/state
enabled
root@MA10014:/home/ubuntu# echo disabled > /sys/kernel/debug/regulator/vdd-usb-hub-en/regulator/state
root@MA10014:/home/ubuntu# cat /sys/kernel/debug/regulator/vdd-usb-hub-en/regulator/state
disabled
root@MA10014:/home/ubuntu# echo disablebad > /sys/kernel/debug/regulator/vdd-usb-hub-en/regulator/state
root@MA10014:/home/ubuntu# cat /sys/kernel/debug/regulator/vdd-usb-hub-en/regulator/state
disabled
root@MA10014:/home/ubuntu# echo enabled > /sys/kernel/debug/regulator/vdd-usb-hub-en/regulator/state
root@MA10014:/home/ubuntu# cat /sys/kernel/debug/regulator/vdd-usb-hub-en/regulator/state
enabled
Is there anything else I need to do for that setting to take effect?
Thanks.