Powercycling USB device on hub

Hans Petter Selasky hselasky at c2i.net
Thu Jul 21 10:51:18 UTC 2011

On Thursday 21 July 2011 12:47:55 Peer Stritzinger wrote:
> Hi,
> On Wed, Jul 20, 2011 at 3:19 PM, Hans Petter Selasky <hselasky at c2i.net> 
> > On Wednesday 20 July 2011 14:30:37 Peer Stritzinger wrote:
> >>...
> >>
> > Using the usbconfig utility in 8 stable and 9 current, you can set the
> > configuration to 255 which means unconfigured and then 0 for the root
> > HUB. For non-root HUBs you can BUS-reset the devices usbconfig -d X.Y
> > reset or set_config aswell.


> Do I understand this right: I reset the USB Hub device to powercycle
> all devices connected to it?

Yes. That is correct.

> >There is also a power_off command, but your device might
> >
> > not come back after that.
> This would probably really not help since I try to reboot a USB device
> with hung software, so it won't recognize any commands itself.

Have you tried usbconfig -d X.Y reset ?

Do a power_off command before the parent HUB reset, if the parent HUB reset is 
not enough. Beware that some motherboards hardwire the powersupply to the USB 
port. I.E. it is not possible to power-cycle the root HUB USB port.


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