Re: S4 hang with uvcvideo causing "Unlink after no-IRQ? Controller is probably using the wrong IRQ."

[Brandon Philips <brandon@ifup.org>]

On 12:43 Sun 08 Mar 2009, Alan Stern wrote:
> On Sat, 7 Mar 2009, Brandon Philips wrote:
> > > Have you tried suspending just the two devices plugged into that EHCI 
> > > controller instead of suspending the entire system?  That would make it 
> > > a lot easier to carry out testing.
> > 
> > I tried to reproduce with s2ram suspend, echo suspend >
> > /sys/bus/usb/devices/.../power/level and /sys/power/pm_test levels but none of
> > them reproduced it. So, at this point the only way I can reproduce this is with
> > a full S4.
> 
> That's a little misleading.

Sorry, what I meant by "full" was `echo disk > /sys/power/state` with
none in /sys/power/pm_test

> Unless I misunderstood your log, the hang occurred _before_ your
> system entered S4.  In fact, it occurred before the memory image was
> written out to the disk.

Yes, this is correct. It freezes before the image is written.

> > Is there some other method I missed of testing?
> 
> How about echo disk >/sys/power/state with various settings in 
> /sys/power/disk?

First observation: I can't reproduce this bug with console=ttyS0,115200
console=tty0. Everything works great actually. Is writing to the serial
port causing just enough delay to hide the bug?

/sys/power/disk tests
---------------------
testproc	# OK
test		# Unlink after no-IRQ? ...
platform	# Unlink after no-IRQ? ...
reboot		# Unlink after no-IRQ? ...
shutdown	# Unlink after no-IRQ? ...

Cheers,

	Brandon