On Fri, 5 Jul 2013, Larry Keegan wrote:

> Dear Chaps,
> 
> I have a Microsoft Basic Optical mouse. When I used an earlier kernel
> (2.6 series) it just worked. However, now that I'm using 3.4.51 it
> suffers from USB disconnects and reconnects every 62 seconds precisely.
> These disconnects do not occur whilst the mouse device is open. I have
> tried two different wired mice in different USB slots of different
> computers with different motherboard types, all to no avail.

Can you post a usbmon trace showing some of those disconnects and 
reconnects?

> What is interesting is that if I connect either mouse to the computer
> via a hub, the timing of the disconnects becomes irregular and
> unpredictable. I often find all the devices on the bus (ie. everything
> but the root hub) disconnect themselves at much the same time as the
> mouse does. Often the mouse doesn't reconnect to the bus. In any case
> plugging in either mouse makes that entire bus distinctly unreliable.
> This problem is not peculiar to any particular hub model.
> 
> I am using a virgin kernel and am not using a well-known user-space
> distribution. I use udev to set up my device nodes, but that's all. To
> me, this has a distinct whiff of USB suspend problems. I have attempted
> to turn off USB suspend by repeatedly writing 'on' to all the
> 'power/control' files under /sys/bus/usb/devices. It did not help. I
> also re-compiled the kernel with power management and usb suspend
> support removed. This didn't help either.

That's a pretty clear indication that USB suspend is _not_ involved.

> I'd appreciate some advice.

It's possible this is an electrical problem -- the bus may not provide
enough power for all the devices on it.

Alan Stern

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