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Message-ID: <54CC57CE.2080001@interlinked.me>
Date: Fri, 30 Jan 2015 22:19:26 -0600
From: Elizabeth Myers <elizabeth@interlinked.me>
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To: Justin Hibbits <jrh29@alumni.cwru.edu>, Adrian Chadd <adrian@freebsd.org>
Subject: Re: Questions on adding backlight support for the i915 driver
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On 01/30/15 17:25, Justin Hibbits wrote:
> Would it make sense to have a generic 'backlight' driver framework
> that we plug into?  I wrote a backlight driver (well, 2, but both show
> up as dev.backlight in sysctl) for powerpc, but if we want to have
> even more individual backlight drivers, I think it makes sense to make
> them all look the same, with similar configuration properties.
> 
> - Justin

I was thinking the same thing myself. There's a lot of different
backlights out there, and acpi_video(4) obviously can't cover them all,
which seems to define the de facto "standard" MIB for brightness sysctls
(which upower presently uses).

I hate to bikeshed, but I would humbly suggest adding an MIB hierarchy
such as hw.backlight.<hw_type>.<backlight_no>.brightness (and maybe
brightness_raw for advanced users who want/need more control).

--
Cheers,
Elizabeth