Re: Changes to PM layer break userspace

From: Arjan van de Ven
Date: Thu Dec 28 2006 - 11:06:05 EST


On Thu, 2006-12-28 at 13:31 +0000, Alan wrote:
> > Seems to me anyone really desperate to put PCI devices into a low
> > power mode, without driver support at the "ifdown" level, would be
> > able just "rmmod driver; setpci".
>
> Incorrect for very obvious reasons - there may be two devices driven by
> the same driver one up and one down.

btw this same "incorrect" applies to the sysfs method, that also does a
more or less uncontrolled/uncoordinated power state switch.

All the more reason to have the "normal" device interfaces do the right
thing, so that the kernel has a standing chance to coordinate it
properly.

--
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