Date: Tue, 27 Jan 2015 00:38:16 -0600 From: "Andrew Wilcox" <AWilcox@Wilcox-Tech.com> To: "'Ranjan1018 .'" <214748mv@gmail.com>, "'Adrian Chadd'" <adrian@freebsd.org>, "'freebsd-current'" <freebsd-current@freebsd.org> Cc: 'Konstantin Belousov' <kib@freebsd.org> Subject: RE: drm2 regression: backlight adjustment on ivybridge no longer works Message-ID: <000e01d039fb$d5959930$80c0cb90$@Wilcox-Tech.com> In-Reply-To: <CACyC=qYMT3VFx4GxypJ6F61pKSaxE0JKBK%2BudDMPSh4_ASAi6w@mail.gmail.com> References: <CAJ-VmomfBrBN6HVBq5FoRf1nRqvrhiDOw6RHjfs13j-9cqi1vg@mail.gmail.com> <CACyC=qYMT3VFx4GxypJ6F61pKSaxE0JKBK%2BudDMPSh4_ASAi6w@mail.gmail.com>
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Ranjan1018 . sent: 26 January 2015 06:19:
> 2015-01-24 23:25 GMT+01:00 Adrian Chadd <adrian@freebsd.org>:
> > The backlight adjustment doesn't work on my ivybridge mobile laptop=20
> > (Lenovo X230) after the dri update.
> >
> I have the same issue on my Samsung Ativ 2 laptop.
I have a Sandy Bridge laptop (Apple MacBook Pro 8,2) - HD 3000:
vgapci0@pci0:0:2:0: class=3D0x030000 card=3D0x00db106b =
chip=3D0x01268086 rev=3D0x09 hdr=3D0x00
vendor =3D 'Intel Corporation'
device =3D '2nd Generation Core Processor Family Integrated =
Graphics Controller'
class =3D display
subclass =3D VGA
It is running: FreeBSD pwyll.foxkit.us 11.0-CURRENT #1 r277781M: Mon =
Jan 26 18:41:15 CST 2015 =
root@pwyll.foxkit.us:/usr/obj/usr/src/sys/GENERIC amd64
I have no issues using acpi_video's sysctls =
(hw.acpi.video.lcd0.brightness) to adjust backlight, though it does not =
have good granularity. The stepping is about 7, so it goes as =
13%..20%..27%..35%..etc.
> > The "intel_backlight" program from intel-gpu-tools" also no longer=20
> > changes the backlight value.
This program works fine for me on both an older kernel (r277523) and =
this kernel (r277781), after applying some patches to allow the library =
to build on FreeBSD. It also has better granularity (the stepping is =
2-3).
If there is anything I can do/run to aide in debugging why it works for =
me but not others, let me know.
Best,
Andrew
--
Andrew Wilcox, C/C++/Python developer, kernel hacker
Blog: http://blog.foxkit.us/ WWW: http://foxkit.us/=20
GitHub: https://github.com/awilfox
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