On Mon, 3 Feb 2014, Josh Bendavid wrote:

> > This shows one of two things: Either your OHCI controller isn't working
> > right (it's issuing IRQs when it's not supposed to) or some other
> > hardware component in your PC is using IRQ 21 when it's not supposed
> > to.
> > 
> > Here's how to tell which is the case.  Enable CONFIG_DUMMY_IRQ in the
> > kernel.  Then shortly after booting, before the "nobody cared" error
> > occurs, do this:
> > 
> >     echo 0000:00:06.0 >/sys/bus/pci/drivers/ohci-pci/unbind
> >     modprobe dummy-irq irq=21
> > 
> > If the "nobody cared" error still occurs, this will prove that the OHCI
> > controller isn't at fault; something else is.  If it doesn't occur,
> > this will prove that the OHCI controller is malfunctioning.

> Indeed doing this the number of interrupts stops increasing, and no error
> occurs.  The dmesg contains the output below.  This therefore means that
> there is a problem with the controller?  Would you suggest I try the
> possible workaround patch you had posted earlier?

The dmesg output is normal.  And yes, lack of any error does indicate 
that something is wrong with your controller.

I don't think this problem can be fixed by a simple workaround.  I've
been considering adding an I/O watchdog to ohci-hcd, because it ought
to help with some issues experienced by other people with buggy OHCI
controllers.  It's _possible_ that this might also help with your
problem -- without knowing exactly what is going wrong in the hardware,
I can't say for certain.

For now, you may be able to bypass the problem by getting a USB-2 hub 
and plugging the infrared and Logitech receivers into it rather than 
directly into the computer.

Alan Stern

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