Re: [RFC] dynamic device power management proposal

[Pavel Machek <pavel@ucw.cz>]

Hi!

> > > > That's not how the USB implementation works.  Although a timestamp like 
> > > > the one you describe is going to be added.
> > > 
> > > I sort of like this idea -- it seems that it is low overhead.
> > > Of course it requires every device driver to be changed.
> > > Instead we could maybe hook the generic driver entry points
> > > and do this in the framework -- dunno if that is viable.
> > 
> > No, you can't get around changing all the drivers.
> > 
> > Generic entry points are for _system_ suspend, and if you try to abuse
> > them for runtime PM, you'll have to audit/change all the drivers.
> 
> Is this your position regarding USB autosuspend, too? Should we use
> other methods than suspend/resume?

Well, you should have audited USB drivers when enabling autosuspend...
But I believe you did that so you are pretty much okay.

(With autosuspend, you can get situation when request from userland
comes in even when device is suspended; some devices will need
fixing).

								Pavel
-- 
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