Re: Cut power to a USB port?

From: Andrew Barr
Date: Tue Jan 02 2007 - 10:29:00 EST


On Tue, 2007-01-02 at 00:32 -0800, Greg KH wrote:
> On Mon, Jan 01, 2007 at 03:56:25PM -0500, Andrew Barr wrote:
> > I have a simple question perhaps someone can help me with here...
> >
> > I have one of those simple LED keyboard lamps that get their power from
> > the USB port. Is there some way in Linux, using files under /sys I would
> > imagine, to cut power to the USB port into which this lamp is plugged? I
> > know I would have to manually figure out what port it's plugged into, as
> > it is not a "real" USB device...e.g. it just draws power. I would like
> > to be able to programmatically switch the lamp on and off.
>
> Search the archives of the linux-usb-devel mailing list for a program
> that might do this for you (depending on your hardware.)

What search terms should I use? Searching on "power" and "port power" at
Gmane in the gmane.linux.usb.devel group doesn't readily give me
anything.

For the record, my hardware:

00:1d.0 USB Controller: Intel Corporation 82801DB/DBL/DBM
(ICH4/ICH4-L/ICH4-M) USB UHCI Controller #1 (rev 01)
00:1d.1 USB Controller: Intel Corporation 82801DB/DBL/DBM
(ICH4/ICH4-L/ICH4-M) USB UHCI Controller #2 (rev 01)
00:1d.2 USB Controller: Intel Corporation 82801DB/DBL/DBM
(ICH4/ICH4-L/ICH4-M) USB UHCI Controller #3 (rev 01)
00:1d.7 USB Controller: Intel Corporation 82801DB/DBM (ICH4/ICH4-M) USB2
EHCI Controller (rev 01)

IBM Thinkpad R51 2883-ELU.

Regards,
Andrew

> good luck,
>
> greg k-h

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/