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<div class="moz-cite-prefix">On 10/06/2013 12:00 PM,
<a class="moz-txt-link-abbreviated" href="mailto:xorg-devel-request@lists.x.org">xorg-devel-request@lists.x.org</a> wrote:<br>
</div>
<blockquote
cite="mid:mailman.7.1381086023.17664.xorg-devel@lists.x.org"
type="cite">
<pre wrap=""><div class="moz-txt-sig">Message: 2
Date: Sun, 06 Oct 2013 11:17:13 -0700
From: Keith Packard <a moz-do-not-send="true" class="moz-txt-link-rfc2396E" href="mailto:keithp@keithp.com"><keithp@keithp.com></a>
To: Mark Kettenis <a moz-do-not-send="true" class="moz-txt-link-rfc2396E" href="mailto:mark.kettenis@xs4all.nl"><mark.kettenis@xs4all.nl></a>
Cc: <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:xorg-devel@lists.freedesktop.org">xorg-devel@lists.freedesktop.org</a>, <a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:kaccardi@gmail.com">kaccardi@gmail.com</a>,
<a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:arjan@linux.intel.com">arjan@linux.intel.com</a>
Subject: Re: [PATCH] Close non-keyboard devices on DPMS off
Message-ID: <a moz-do-not-send="true" class="moz-txt-link-rfc2396E" href="mailto:86siwe463a.fsf@miki.keithp.com"><86siwe463a.fsf@miki.keithp.com></a>
Content-Type: text/plain; charset="utf-8"
Mark Kettenis <a moz-do-not-send="true" class="moz-txt-link-rfc2396E" href="mailto:mark.kettenis@xs4all.nl"><mark.kettenis@xs4all.nl></a> writes:
</div></pre>
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<pre wrap=""><span class="moz-txt-citetags">> </span>Is that really desirable?
</pre>
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<pre wrap="">It has a couple of benefits -- the first is that touch screens and touch
pads often get input while your laptop screen is closed; this prevents
that from waking up the X server.
The second is that turning off input devices can allow the system to
shut down USB resources and save a bunch of power. I posted the patch so
that we could get measurements of the power savings.
</pre>
</blockquote>
<blockquote
cite="mid:mailman.7.1381086023.17664.xorg-devel@lists.x.org"
type="cite">
<blockquote type="cite" style="color: #000000;">
<pre wrap=""><span class="moz-txt-citetags">> </span>For me, moving the mouse has always been the most natural way to wake
<span class="moz-txt-citetags">> </span>up the screen.
</pre>
</blockquote>
<pre wrap="">Yeah, that's the usual way I wake my machine up as well. However, if you
try this on an OS X machine, you'll find that only the keyboard will
wake the machine up. So, it's not a universal policy at least.
</pre>
<blockquote type="cite" style="color: #000000;">
<pre wrap=""><span class="moz-txt-citetags">> </span>And I can imagine that touching the screen is the most
<span class="moz-txt-citetags">> </span>natural way to do it on a device with a touchscreen. Such devices
<span class="moz-txt-citetags">> </span>might not even have keyboard.
</pre>
</blockquote>
<pre wrap="">It's hard to imagine a device without <b class="moz-txt-star"><span class="moz-txt-tag">*</span>any<span class="moz-txt-tag">*</span></b> keys, but it's certainly
possible. The trick would be to figure out how to detect this
automatically; my machine lists six "keyboard" devices:
? Power Button id=6 [slave keyboard (3)]
? Power Button id=8 [slave keyboard (3)]
? Sleep Button id=9 [slave keyboard (3)]
? FaceTime HD Camera (Built-in) id=11 [slave keyboard (3)]
? Apple Inc. Apple Internal Keyboard / Trackpad id=12 [slave keyboard (3)]
? Video Bus id=7 [slave keyboard (3)]
I think the interesting part here is the potential for power savings
while the screen is blanked; getting some idea of how much closing the
other devices is worth would be really helpful in figuring out when to
make this choice.
<div class="moz-txt-sig">--
<a moz-do-not-send="true" class="moz-txt-link-abbreviated" href="mailto:keith.packard@intel.com">keith.packard@intel.com</a></div></pre>
</blockquote>
Keith, why do you want to fix something that isn't broken, by
breaking it? You say it's hard to imagine a device without *any*
keys, well such 'devices' are the ONLY kind of devices I ship
running the X server. These are not battery operated machines so
the advantage of saving power doesn't exist. What is wrong with
waking up a touchscreen driven computer by touching the screen?
There's nothing wrong with it! <br>
<br>
--Gene Mosher<br>
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