Re: [linux-pm] runtime PM usage_count during driver_probe_device()?

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

On Friday, July 01, 2011, Alan Stern wrote:
> On Fri, 1 Jul 2011, Rafael J. Wysocki wrote:
> 
> > Hi,
> > 
> > On Friday, July 01, 2011, Kevin Hilman wrote:
> > > Alan Stern <stern@rowland.harvard.edu> writes:
> > > 
> > > > On Fri, 1 Jul 2011, Kevin Hilman wrote:
> > > >
> > > >> OK, so the ->probe() part has been explained and makes sense, but I
> > > >> would expect ->remove() to be similarily protected (as the documentation
> > > >> states.)  But that is not the case.  Is that a bug?  If so, patch below
> > > >> makes the code match the documentation.
> > > >
> > > > I suspect it is a bug, but it's hard to be sure.  It's so _blatantly_ 
> > > > wrong that it looks like it was done deliberately.
> > > 
> > > heh
> > 
> > I seem to remeber having a problem with the pm_runtime_put_sync() after
> > drv->remove(dev) ...
> > 
> > So the code in question was introduced by
> > 
> > commit e1866b33b1e89f077b7132daae3dfd9a594e9a1a
> > Author: Rafael J. Wysocki <rjw@sisk.pl>
> > Date:   Fri Apr 29 00:33:45 2011 +0200
> > 
> >     PM / Runtime: Rework runtime PM handling during driver removal
> > 
> > with a long changelog explaining the reason why.  Which seems to make sense. ;-)
> 
> Okay, that seems fair enough.  Looks like the documentation needs to be 
> updated to match, though.

Yes, it does.

> And we probably still want to make sure that access to the 
> power/control and related attribute files is mutually exclusive with 
> probe and remove.

I agree.

Thanks,
Rafael