From mboxrd@z Thu Jan 1 00:00:00 1970 From: Liu Xinyun Subject: fix backlight resets to minium when changing resolution Date: Wed, 10 Nov 2010 00:42:50 +0800 Message-ID: <20101109164250.GA8905@woliu-sh> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga03.intel.com (mga03.intel.com [143.182.124.21]) by gabe.freedesktop.org (Postfix) with ESMTP id 862B99E78A for ; Tue, 9 Nov 2010 08:43:58 -0800 (PST) Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Chris Wilson Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org It is reported as https://bugs.freedesktop.org/show_bug.cgi?id=29716. find the regression and here is the fix, maybe ugly. diff --git a/src/intel_display.c b/src/intel_display.c index d32224e..4a159bf 100644 --- a/src/intel_display.c +++ b/src/intel_display.c @@ -339,6 +339,8 @@ intel_crtc_apply(xf86CrtcPtr crtc) if (output->crtc != crtc) continue; + /* Turn on any outputs on this crtc that may have been disabled */ + intel_output_dpms(output, DPMSModeOn); intel_output = output->driver_private; output_ids[output_count] = -------- this regression is caused by this commit. In fact, KMS doesn't not handle backlight properly as we think. I don't know where to put the code, so I use above code in xf86-intel-driver to fix this issue. In fact, KMS initialize mode as DPMSOFF, and X set to it to ON after start. And if any mode is changed, it will set to 'correct' status: OFF. Thus xrandr can not change backlight any more. So a better solution shoule be there. Any suggestion? 19c48d3b3f33582baa87a9b3a9189e320e4cea45 is the first bad commit commit 19c48d3b3f33582baa87a9b3a9189e320e4cea45 Author: Chris Wilson Date: Mon Aug 9 10:13:58 2010 +0100 display: outputs are enabled automatically by KMS When an output is attached to a crtc and that crtc is enabled, the output is automatically enabled so we can remove the redundant manual dpms on. Signed-off-by: Chris Wilson Regards, Xinyun