Re: [Regression]: Changing brightness does not work with v3.16-rc4

[Julian Wollrath <jwollrath@web.de>]

Am Mon, 14 Jul 2014 20:21:19 +0200
schrieb "Rafael J. Wysocki" <rjw@rjwysocki.net>:

> On Saturday, July 12, 2014 06:24:52 PM Julian Wollrath wrote:
> > Hi,
> > 
> > > changing the brightness on my Thinkpad X230 with Intel HD4000
> > > graphics, stopped working after commit 886129a8eebe (ACPI / video:
> > > change acpi-video brightness_switch_enabled default to 0).
> > > Changing it back to 1, fixes the problem, if "acpi_osi=!Windows
> > > 2012" is also set. Before that commit just setting
> > > "acpi_osi=!Windows 2012" was enough to get changing the
> > > brightness working.
> >
> > small correction: It setting "acpi_osi=!Windows 2012" does only help
> > when using a kernel with commit 886129a8eebe as HEAD, with v3.16-rc4
> > setting video.brightness_switch_enabled=1 and acpi_osi=!Windows
> > 2012 or just one of them, does not make changing the brightness
> > work again.
> 
> And reverting commit 751109aad583 (ACPI / video: Change the default
> for video.use_native_backlight to 1) make that last problem go away,
> right?
> 
> We are going to rever commit 886129a8eebe for other reasons, so can
> you please revert it from 3.16-rc5 on your system and report back?
Yes, with both 751109aad583 and 886129a8eebe reverted, changing the
brightness works again.

Cheers,
Julian

> 
> Rafael
>