Re: [regression, bisected] adb trackpad disappears after suspend to ram

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Friday 29 May 2009, Jan Scholz wrote:
> Benjamin Herrenschmidt <benh@kernel.crashing.org> writes:
> 
> >> We are too late in the cycle to revert this commit and it really is needed to
> >> fix a more serious issue.  Nevertheless knowing that it caused the problem to
> >> appear on your system is also important.
> >> 
> >> Ben, do you have an idea what may be going on here?  Does __disable_irq() mask
> >> the interrupt on this platform?
> >
> > I suppose so :-) I'll have to check what's going on, it's not
> > immediately clear to me.
> >
> > Cheers,
> > Ben.
> >
> >> 
> >> I'd like to see a boot log, preferably containing a suspend-resume in which
> >> the problem was reproduced.
> 
> Here is a log from booting, through several suspend cycles, until the
> trackpad disappeared. The first few suspends were done while X was
> running but from the console. As you can tell from lines like
>    May 28 23:51:26 [kernel] adb devices: [2]: 2 c4 [3]: 3 1 [7]: 7 1f
> the trackpad was still present. The last suspend was done from within X,
> here the trackpad did not make it.
>    May 28 23:58:09 [kernel] adb devices: [2]: 2 c4 [7]: 7 1f
> However, there have been cases, although not in this log, were the
> trackpad has been alive even when suspending from within X.

This means the problem is probably timing-related.

Can you please try to comment out suspend_device_irqs() and
resume_device_irqs()  in drivers/base/power/main.c and see if that changes
anything?  It's not entirely safe (well, that's why the calls are there after
all), but hopefully the box won't hang during this test.

Best,
Rafael