drm/i915: do not disable backlight on vgaswitcheroo switch off
On muxed systems, the other vgaswitcheroo client may depend on i915 to
handle the backlight. We began switching off the backlight since
commit a261b246ebd552fd5d5a8ed84cc931bb821c427f
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Jul 26 19:21:47 2012 +0200
drm/i915: disable all crtcs at suspend time
breaking backlight on discreet graphics in (some) muxed systems.
Keep the backlight on when the state is changed through vgaswitcheroo.
Note: The alternative would be to add a quirk table to achieve the same
based on system identifiers, but AFAICS it would asymptotically approach
effectively the same as this patch as more IDs are added, but with the
maintenance burden of the quirk table.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=55311
Tested-by: Fede <fedevx@yahoo.com>
Tested-by: Aximab <laurent.debian@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59785
Tested-by: sfievet <sebastien.fievet@free.fr>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
1 file changed