From: Scot Doyle <lkml14@scotdoyle.com>
Date: Thu, 3 Jul 2014 23:27:51 +0000 (+0000)
Subject: drm/i915: Acer C720 and C720P have controllable backlights
X-Git-Tag: v3.15.6~18
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=31b66c21cde8100f2ae64600c66bf58c8f5b5d5d;p=thirdparty%2Fkernel%2Fstable.git

drm/i915: Acer C720 and C720P have controllable backlights

commit 2e93a1aa9ca455aa3ad0294bcd6d66f38bf8b758 upstream.

The Acer C720 and C720P Chromebooks (with Celeron 2955U CPU) have a
controllable backlight although their VBT reports otherwise. Apply quirk
to ignore the backlight presence check during backlight setup.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79813
Tested-by: James Duley <jagduley@gmail.com>
Tested-by: Michael Mullin <masmullin@gmail.com>
Signed-off-by: Scot Doyle <lkml14@scotdoyle.com>
CC: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
[danvet: Add cc: stable because the regressing commit is in 3.15.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 7d7d98c70ef66..3c58d0972e9d2 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -11245,6 +11245,9 @@ static struct intel_quirk intel_quirks[] = {
 
 	/* Acer Aspire 5336 */
 	{ 0x2a42, 0x1025, 0x048a, quirk_invert_brightness },
+
+	/* Acer C720 and C720P Chromebooks (Celeron 2955U) have backlights */
+	{ 0x0a06, 0x1025, 0x0a11, quirk_backlight_present },
 };
 
 static void intel_init_quirks(struct drm_device *dev)