From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: Screen extremely dim on Dell Latitude D630 after upgrading to Linux kernel-3.14 Date: Mon, 26 May 2014 12:57:42 +0300 Message-ID: <8738fw276x.fsf@intel.com> References: <537E5B6D.1030408@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id A816A6E285 for ; Mon, 26 May 2014 02:58:13 -0700 (PDT) In-Reply-To: <537E5B6D.1030408@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Marc Milgram , intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Thu, 22 May 2014, Marc Milgram wrote: > After upgrading to linux Kernel-3.14, the screen on my Dell Latitude > D630 was nearly unreadably dim. When I Boot the 3.13 kernel, my screen > is bright. Please file a new bug on DRM/Intel at [1]. Please attach /sys/kernel/debug/dri/0/i915_opregion and dmesg with drm.debug=0xe module parameter set. Also include info whether max_brightness changes for you between 3.13 and 3.14. Do the later 3.15-rc kernels work for you? BR, Jani. [1] https://bugs.freedesktop.org/enter_bug.cgi?product=DRI > > I opened a Bug here: https://bugzilla.redhat.com/show_bug.cgi?id=1094066 > and others have chimed in that they have the same problem. > > I bisected the kernel, and found the following commit is responsible for > this problem: > > b35684b8fa94e04f55fd38bf672b737741d2f9e2 is the first bad commit > commit b35684b8fa94e04f55fd38bf672b737741d2f9e2 > Author: Jani Nikula > > Date: Thu Nov 14 12:13:41 2013 +0200 > > drm/i915: do full backlight setup at enable time > > We should now have all the information we need to do a full > initialization of the backlight registers. > > v2: Keep QUIRK_NO_PCH_PWM_ENABLE for now (Imre). > > Signed-off-by: Jani Nikula > > Reviewed-by: Imre Deak > > Signed-off-by: Daniel Vetter > > > :040000 040000 0aae5515ca62ff1bfd2e1c2769e30c58b016ffeb 01c2f8cd145f8cf29730908d52e7e89b787a059e M drivers > > I can find my way around the kernel, but haven't hit this area before. > > Any help is appreciated. > > Marc Milgram > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Jani Nikula, Intel Open Source Technology Center