Messages in this thread | | | Date | Fri, 5 Jun 2009 14:39:09 +0100 | Subject | Re: [PATCH] eeepc-laptop: enable camera by default | From | Alan Jenkins <> |
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On 6/5/09, Corentin Chary <corentin.chary@gmail.com> wrote: > On Fri, Jun 5, 2009 at 2:44 PM, Pekka Enberg<penberg@cs.helsinki.fi> wrote: >> Hi Corentin, >> >> On Fri, 2009-06-05 at 13:46 +0200, Corentin Chary wrote: >>> First, I think a one line >>> set_acpi(CM_ASL_CAMERA, 1); >>> with a small comment is better. (If it fails, it's because there no >>> camera, so we don't mind). >> >> OK, I've included an updated version of the patch. >> >> On Fri, 2009-06-05 at 13:46 +0200, Corentin Chary wrote: >>> Anyway, I'm not sure it's a good idea to enable the camera by default. >>> It depends how many power the camera is using (when idle). Coud you >>> check that (with power top maybe ?). >> >> People who prefer power savings over functional camera can always >> disable it. If you look at the amount of "my camera doesn't" work bug >> reports, I think it's pretty evident that we should enable it by default >> or provide a config option that does it. > > Ok, your right, I'll apply that one > >> That said, I am more than happy to measure this but I need a little bit >> more information to get started as I have never used powertop. So what >> is it exactly you want me to do? > > PowerTop (with a corretly configured kernel) will give you a power > usage estimate. > > CONFIG_NO_HZ=y > CONFIG_TIMER_STATS=y > CONFIG_DEBUG_KERNEL=y > > For propers results, shutdown all services and just keep a shell > (without X or network). > You can also test that with and without the camera driver.
Hmm, this relies on good acpi battery information, I hope your EeePC is better than mine in that regard.
The ideal solution is if USB auto-suspend could be used to save the same amount. Google says there was a patch for uvcvideo last year [1]. I'll see what the current status is on my model and report back :-).
[1] <http://lists.berlios.de/pipermail/linux-uvc-devel/2008-January/002707.html>
Alan
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