Re: [PATCH] PM: add synchronous runtime interface for interrupt handlers

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

On Sunday, October 03, 2010, Alan Stern wrote:
> On Sun, 3 Oct 2010, Rafael J. Wysocki wrote:
> 
> > On Saturday, October 02, 2010, Alan Stern wrote:
> > > On Fri, 1 Oct 2010, Rafael J. Wysocki wrote:
> > ...
> > > > At the moment it suspends when the network cable is removed from the device
> > > > and the hack I mentioned is used during the resume after the cable has been
> > > > reinserted (it checks if the cable is still there and schedules suspend if not).
> > > 
> > > That does seem like a strange hack.  Instead of scheduling a suspend,
> > > why not simply do a suspend as soon as you learn that the cable has
> > > been removed again?  Is there a problem about the connection status
> > > bouncing?
> > 
> > I don't remember 100%, but ISTR there was a problem with that.
> 
> Regardless, it seems like the sort of thing autosuspend would handle
> easily with no need for idle notifications.  Just call
> pm_runtime_mark_last_busy when the cable is plugged in, then do the
> runtime resume, and then call pm_request_autosuspend.  The check for 
> the cable being disconnected would have to move from the runtime_idle 
> callback to the runtime_suspend callback -- but then the runtime_idle 
> callback wouldn't have to be present at all.

It would be necessary because of the PCI bus type's implementation of it.

Anyway, I'll have a look, but I don't use the hardware any more, so testing
would be rather hard. :-)

Thanks,
Rafael