When I try to get the voltage from usb port with: # lsusb -v | grep 'Bus\MaxPower' [root@freeBSD ~]# lsusb -v | grep 'Bus\Maxpower' can't get debug descriptor: Input/output error can't get debug descriptor: Input/output error can't get debug descriptor: Input/output error can't get device qualifier: Input/output error can't get debug descriptor: Input/output error can't get device qualifier: Input/output error can't get debug descriptor: Input/output error
Try: lsusb -v |& grep 'Bus\Maxpower'