From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mark Brown <broonie@opensource.wolfsonmicro.com>
Subject: Re: [linux-pm] [RFC] input: syfs switches for SKE keypad
Date: Wed, 13 Oct 2010 10:57:37 +0100
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To: Sundar R IYER <sundar.iyer@stericsson.com>
Cc: Alan Stern <stern@rowland.harvard.edu>, "samu.p.onkalo@nokia.com" <samu.p.onkalo@nokia.com>, Linus WALLEIJ <linus.walleij@stericsson.com>, Naveen Kumar GADDIPATI <naveen.gaddipati@stericsson.com>, Dmitry Torokhov <dmitry.torokhov@gmail.com>, "linux-input@vger.kernel.org" <linux-input@vger.kernel.org>, Linux-pm mailing list <linux-pm@lists.linux-foundation.org>, Jayeeta BANDYOPADHYAY <jayeeta.banerjee@stericsson.com>

On Wed, Oct 13, 2010 at 08:16:20AM +0200, Sundar R IYER wrote:

> >> This isn't *really* about saving power in the individual device; it's
> >> more about stopping the device generating events that disrupt the rest
> >> of the system.  Suspending the device can be one way of doing that and
> >> is useful if it can be done but is not really the immediate goal here.

> >Runtime PM is _not_ a reliable way of preventing a device from
> >generating events.  It is meant for saving energy, nothing else.

> >If that's what this is about, then the answer is simple: Don't use
> >runtime PM to try to suppress events.

> I think it is unfair to discriminate here about saving power and turning off
> events. I believe putting the device into power save leads to, if device permits
> preventing generating events is valid to hook up run time PM.

This is the opposite way around to expectations - the expectation is
that runtime power management will flow from the device becoming idle
enough to turn off rather than the other way around.