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Date: Mon, 16 Feb 2009 12:45:20 -0800
From: Arjan van de Ven <arjan@infradead.org>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Kyle Moffett <kyle@moffetthome.net>, Oliver Neukum <oliver@neukum.org>,
       Benjamin Herrenschmidt <benh@kernel.crashing.org>,
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Subject: Re: [RFD] Automatic suspend
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On Mon, 16 Feb 2009 15:39:15 -0500 (EST)
Alan Stern <stern@rowland.harvard.edu> wrote:

> On Mon, 16 Feb 2009, Kyle Moffett wrote:
> 
> > Userspace may not have a useful decision-making capability regarding
> > functionality versus power-saving, but the user it's talking to
> > might!
> > 
> > I think it would be very useful to have a mechanism for userspace to
> > find out "Link detection on this NIC costs ~50mW" and "No link has
> > been detected for the last 15 minutes", so that it can compile all
> > that sort of information and prompt the user what devices they would
> > like to disable.  Perhaps an "airline mode" sort of thing?
> 
> Even if drivers don't know how much power their devices consume (and
> generally I wouldn't expect them to), it still makes sense to offer
> userspace the discretionary power to force devices into a low-power
> mode.  USB does this.

"stop using it" isn't this discretionary power ?
(for NICs this is "ifconfig .. down")

-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org