From patchwork Fri Apr 19 16:41:38 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 238052 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id DD4B82C01E4 for ; Sat, 20 Apr 2013 02:41:59 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UTENi-0001Js-4z; Fri, 19 Apr 2013 16:41:50 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UTENc-0001JT-Ts for kernel-team@lists.ubuntu.com; Fri, 19 Apr 2013 16:41:44 +0000 Received: from c-67-160-231-42.hsd1.ca.comcast.net ([67.160.231.42] helo=[192.168.1.7]) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1UTENc-000305-FW; Fri, 19 Apr 2013 16:41:44 +0000 Message-ID: <1366389698.4705.14.camel@fourier> Subject: [Raring SRU][PULL] fix XPS13-FHD backlight regression From: Kamal Mostafa To: kernel-team@lists.ubuntu.com Date: Fri, 19 Apr 2013 09:41:38 -0700 X-Mailer: Evolution 3.6.2-0ubuntu1 Mime-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com Bug reference: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1169376 XPS13 backlight stopped working after update 3.8.0-18.28 [IMPACT] My recent sauce patch for LP: #1162026 (Raring 9742db3) applied a quirk to fix the backlight controls on two variants of the Dell XPS13, but it turns out that the quirk is only appropriate for the original 768p model (there was some misunderstanding about which models needed it). The new Dell XPS13 "FHD" 1080p model is actually adversely affected by the quirk, yielding dark screen on boot and no backlight controls. This patch removes the 1080p model from the dmi quirk table, restoring its backlight behavior to normal functionality. [TESTCASE] The bug reporter in LP: #1169376 has confirmed that a test kernel with the patch applied fixes it for his 1080p model. I have confirmed that the original quirk patch still works on my 768p model. [Regression Potential] Low regression potential: the change only affects the Dell XPS 13 "FHD" 1080p model, returning its i915 backlight controls to the standard mainline (pre 3.8.0-18.28) behavior. Thanks, -Kamal -------- >8 ---------------------------------------------------- The following changes since commit 10e251b7b13b2c727d58a7d3ed4451667366ad12: UBUNTU: SAUCE: (no-up) ACPI: Disable Windows 8 compatibility for some Lenovo ThinkPads (2013-04-19 07:29:30 -0700) are available in the git repository at: git://kernel.ubuntu.com/kamal/ubuntu-raring.git lp1169376-xps13-fhd for you to fetch changes up to ba44c190aafad79f11e6b5477de26f81b8fdb3ac: UBUNTU: SAUCE: (no-up) drm/i915: quirk no PCH_PWM_ENABLE only Dell XPS13 SandyBridge (2013-04-19 08:52:52 -0700) ---------------------------------------------------------------- Kamal Mostafa (1): UBUNTU: SAUCE: (no-up) drm/i915: quirk no PCH_PWM_ENABLE only Dell XPS13 SandyBridge drivers/gpu/drm/i915/intel_display.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index d7231cb..b56b846 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -8893,9 +8893,8 @@ static const struct intel_dmi_quirk intel_dmi_quirks[] = { }; static struct intel_quirk intel_quirks[] = { - /* Dell XPS13 models */ + /* Dell XPS13 SandyBridge */ { 0x0116, 0x1028, 0x052e, quirk_no_pcm_pwm_enable }, - { 0x0166, 0x1028, 0x058b, quirk_no_pcm_pwm_enable }, /* HP Mini needs pipe A force quirk (LP: #322104) */ { 0x27ae, 0x103c, 0x361a, quirk_pipea_force },