Re: usb devices get redetected all the time in 2.6.0-test{7,9}

From: Soeren Sonnenburg
Date: Thu Oct 30 2003 - 01:29:24 EST


On Wed, 2003-10-29 at 21:01, Greg KH wrote:
> On Wed, Oct 29, 2003 at 08:15:26AM +0100, Soeren Sonnenburg wrote:
> > Hi.
> >
> > When I attach a camera to a 2.4. based machine hotplug starts up some
> > script to download images of that camera and fine thats it.
> >
> > In 2.6.0-testX I see kernel messages like:
> >
> > hub 2-0:1.0: new USB device on port 1, assigned address 2
> > bus usb: add device 2-1
> > bound device '2-1' to driver 'usb'
> > bus usb: add device 2-1:1.0
> > bus usb: remove device 2-1:1.0
> > bus usb: add device 2-1:1.0
> > bus usb: remove device 2-1:1.0
> > bus usb: add device 2-1:1.0
> > bus usb: remove device 2-1:1.0
> > bus usb: add device 2-1:1.0
> > [...]
> >
> > and several of these hotplug scripts get started... Is this a wanted
> > behaviour and something has to be fixed in userspace or is it a kernel
> > bug ?
>
> Does this settle down after a bit, or does the add/remove stuff keep
> going on for a while?

I realized that when I disable the hotplug script the camera is detected
only once (as it should).

The script fetches the directory listing off the camera... thus is
probably opening+closing the device once. So I wonder whether this could
somehow trigger an usb disconnect on close() making the usb driver to
redetect the device ?!

> Can you enable CONFIG_USB_DEBUG and see if you get any more information
> in the kernel debug log as to why this is happening?

If still needed I will do.

Soeren

-
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/