[linux-pm] calling runtime PM from system PM methods

Alan Stern stern at rowland.harvard.edu
Fri Jun 10 10:17:56 PDT 2011


On Fri, 10 Jun 2011, Mark Brown wrote:

> > Well, this is a SHOULD, not a MUST.  If you want your driver to leave a
> > device in a low-power state, it can do so.  Just bear in mind that the
> > PM core's idea of the device's runtime power state may end up not
> > matching reality unless you're careful.
> 
> This is part of the trouble, it all feels like a lot more work than it
> should be for relatively common cases.  In the audio case we're fine as
> the subsystem implements a completely independent PM infrastructure
> which ignores the PM core except for system suspend (and sometimes
> ignores that), it's noticably harder to reason about what's going on
> when I go outside there and when I think about what I'm doing it always
> feels like it should be possible to factor it out of the drivers.

What would make the common cases easier?

Alan Stern



More information about the linux-pm mailing list