Re: [linux-pm] runtime_pm_get_sync() from ISR with IRQs disabled?

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

On Friday, September 24, 2010, Kevin Hilman wrote:
> Alan Stern <stern@rowland.harvard.edu> writes:
> 
> > On Thu, 23 Sep 2010, Kevin Hilman wrote:
...
> >
> > You're trying to fight the runtime-PM design instead of using it as it 
> > was intended.  We already have an API for starting a resume from 
> > interrupt context, and that's what you should use.
> 
> It may seem like I'm trying to fight the design, but I'm actually trying
> to find ways to use it.  I want to use the API (and we're using it
> successfully in most of our drivers now.)  The problem is only in a few
> of these corner cases where using it introduces significant changes from
> previous behavior like introducing long, unbounded windows for missed
> interrupts.

This really sounds to me like you need _noirq() runtime PM callbacks
and some framework around them.

I'm not fundamentally against that, but it will require some time to introduce,
if we decide that it's really necessary.

I need to think a bit more about that, thanks for the example.

Rafael