Re: Panda ES board hang when using GPIO as interrupt

["Franky Lin" <frankyl@xxxxxxxxxxxx>]

On 06/28/2012 08:42 AM, Jon Hunter wrote:
> On 06/27/2012 07:41 PM, Franky Lin wrote:
> > On 06/26/2012 08:37 PM, Kevin Hilman wrote:
> > > "Franky Lin" <frankyl@xxxxxxxxxxxx> writes:
> > > > I noticed Kevin raised some similar cases on other platforms and also
> > > > provided two patches in the patch mail thread. But unfortunately those
> > > > two patches doesn't help in our case. I tested the driver with 3.5-rc3
> > > > mainline kernel and the issue is still there. I can only "fix" the
> > > > hang by either reverting the commit or disabling
> > > > CONFIG_PM_RUNTIME. Also, the hang only happens on Panda ES board. Old
> > > > Panda with 4430 works good.
> > > >
> > > > Any thoughts and suggestions?
> > >
> > > If reverting the patch fixes your problem, can you isolate down to which
> > > part of that patch causes the problem?  IOW, can you fix your problem if
> > > you undo just the hunk added in runtime_suspend or undo just the moved
> > > hunk runtime_resume?  Or is reverting both required?
> > >
> > > I suspect the added runtime_suspend hunk is causing the problems, so can
> > > you see if just undoing that part works[1].  If that works, I will give
> > > a bit more of a thinking on it tomorrow.
> >
> > runtime_suspend hunk is fine. The hang still exist after reverting it.
> > The culprit is the moved hunk in runtime_resume. Reverting it makes the
> > hang disappear.
>
> Thanks. From reviewing the code the only thing that appears suspect based
> upon your findings is the return if we find the context has not been lost.
> We are not checking if "workaround_enabled" is set before we return.
>
> Could you try the following change on top of v3.5-rc3?

The patch doesn't help. And I also managed to probe the signal. It's 
active when it hung.

> Also, could you add a print in the runtime_suspend/resume() functions so
> we can see how often these are being called. In my case, I really don't see
> these being exercised and I am wondering how often you see suspend/resume
> being called in your setup.

Well, the runtime_suspend/resume never get called during the test.

Thanks,
Franky


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel