Re: Repeated USB disconnect and reconnect with Wacom Intuos3 6x11 tablet

[Greg KH <greg@kroah.com>]

On Thu, Dec 15, 2005 at 03:42:54PM +0100, Denny Priebe wrote:
> On Tue, Dec 13, 2005 at 11:38:32AM -0800, Greg KH wrote with possible deletions:
> 
> Hello,
> 
> > > These disconnects and reconnects disappear as soon as there's 
> > > a process reading either /dev/input/mouse0 or /dev/input/event5 
> > > (mouse0 and event5 according to my setup).
> 
> > Sounds like a hardware problem, the kernel can't cause a device to
> > electronically disconnect itself like this.
> 
> thanks for your reply, Greg.
>  
> > I suggest plugging this into a different port, using a powered hub, or
> > checking that the cable is still good.
> 
> I tried what you have suggested. Unfortunately, this doesn't change 
> anything.
> 
> What confuses me a bit is that theses USB disconnects do not appear
> as soon as I read what the tablet provides.
> 
> Could it be that the usb driver doesn't check for a connect status change
> while there's a process reading /dev/input/{mouse,event}? so that I do not
> see these disconnects while reading the tablet data? 

No, it's an electronic signal happening on the USB hub, the hub notifies
the kernel when a disconnect happens, it has nothing to do with the
driver connected to the actual device.

So I really think that this is an electronic issue, sorry.  Can you
return this device and get a replacement one?

greg k-h
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