Re: Linux 3.11-rc2

[Martin Steigerwald <Martin@lichtvoll.de>]

Am Montag, 22. Juli 2013, 15:37:42 schrieb Rafael J. Wysocki:
> On Monday, July 22, 2013 03:15:38 PM Martin Steigerwald wrote:
> > Am Montag, 22. Juli 2013, 15:02:22 schrieb Rafael J. Wysocki:
> > > On Monday, July 22, 2013 12:08:40 AM James Hogan wrote:
> > > > On 21 July 2013 20:53, Linus Torvalds <torvalds@linux-foundation.org>
> > 
> > wrote:
> > > > >  (b) we had a late change to how ACPI backlight handling is done on
> > > > > 
> > > > > certain machines, and while this kind of thing really shouldn't be
> > > > > done outside the merge window, I ended up pulling it anyway. But I'd
> > > > > *really* like to have people test this thing particularly on laptops
> > > > > with intel-based graphics. It should only matter (and hopefully
> > > > > improve things) for the newer ones with BIOSes designed for Windows
> > > > > 8,
> > > > > but hey, the more testing, the better. Backlight handling has beenin
> > > > > painful before, so I'm mentioning this explicitly.
> > > > 
> > > > 8c5bd7a "ACPI / video / i915: No ACPI backlight if firmware expects
> > > > Windows 8" breaks backlight control for me because
> > > > /sys/class/backlight/acpi_video0 disappears, and
> > > > /sys/class/backlight/intel_backlight doesn't seem to have any effect.
> > > > 
> > > > Note that acpi_video0 only worked because I was applying "[PATCH]
> > > > drm/i915: quirk no PCH_PWM_ENABLE for Dell XPS13 backlight" [1], so
> > > > strictly speaking mainline already didn't work.
> > > 
> > > James, sorry for breaking things for you.  The patch you're mentioning
> > > is
> > > going to hit the mainline at one point anyway I suppose.
> > 
> > Dunno whether thats related, but after locking screen today and screen
> > blanker kicking in (just a blank screen), I was not able to reactivate
> > the display again by typing a key or so unless I closed the laptop
> > display lid, let the machine suspend (to ram) and opened it again.
> 
> > Plain 3.11-rc2 on ThinkPad T520:
> Well, please try to revert commits efaa14c and 8c5bd7a (in this order) and
> see if that helps.

Okay. Done that. It does help.

Thanks,
-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA  B82F 991B EAAC A599 84C7