Messages in this thread | | | Date | Mon, 22 Jun 2009 12:28:14 -0400 (EDT) | From | Alan Stern <> | Subject | Re: [patch update 3] PM: Introduce core framework for run-time PM of I/O devices |
| |
On Mon, 22 Jun 2009, Rafael J. Wysocki wrote:
> > Again, this boils down to how drivers decide to use the async > > interface. I can see justifications for both pm_request_resume_get > > (which would always increment the counter) and pm_request_resume (which > > would increment the counter only if a work item had to be queued). > > OK, so this means we should provide both at the core level and let the drivers > decide which one to use. > > I think in both cases the caller would be responsible for decrementing the > counter?
Sure. They could call pm_runtime_put just once at the end of their runtime_resume method (assuming they used pm_request_resume), or they could call it at every place where some deferred work was finished (assuming they used pm_request_resume_get).
> > Okay, we don't need it then. I forgot to mention in the previous > > message that there also has to be a pm_runtime_del() routine, which > > should cancel pending workqueue items and set the counter to some high > > value so that no new items are added. > > Should that be called by device_pm_remove()? I think so.
Yes. I suppose it could be named pm_runtime_remove. Either would be okay.
Alan Stern
| |