From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Subject: PROBLEM: Acer D255E Backlight out for 10 seconds with ACPI Date: Wed, 26 Sep 2012 16:48:53 -0400 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: Received: from mail-bk0-f46.google.com ([209.85.214.46]:41961 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751303Ab2IZUsz (ORCPT ); Wed, 26 Sep 2012 16:48:55 -0400 Received: by bkcjk13 with SMTP id jk13so629732bkc.19 for ; Wed, 26 Sep 2012 13:48:54 -0700 (PDT) Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linux-acpi@vger.kernel.org Hello, Apologies if this was sent to the wrong place. With an Acer AOD255E netbook, the backlight goes out for exactly 10 seconds before returning while booting. This is a backlight issue and not KMS, as I can shine a flashlight at the screen and still see boot text scrolling. With "acpi=off" appended to the kernel line, this no longer occurs (Fn key backlight controls still work with this appended). With every other acpi option I have tried, this still occurs though. This includes "acpi_backlight" and "acpi_display_output". With "acpi_backlight=vendor" the entry in /sys/class/backlight changes from acpi_video0 to acer_wmi, but backlight still goes out. Otherwise backlight works correctly. Kernel version (I have reproduced it with several other older kernels as well on different distributions): Linux version 3.5.4-1-ARCH (tobias@T-POWA-LX) (gcc version 4.7.1 20120721 (prerelease) (GCC) ) #1 SMP PREEMPT Sat Sep 15 08:12:04 CEST 2012 I compiled the system information from /proc and lspci here (You can also find a dmesg comparision between a regular boot and one with acpi disabled here): http://pastebin.com/u/vxl I'll also point you to the Ubuntu bug report I filed awhile back while using that. It contains information on the exact same system (running Ubuntu rather than Arch Linux): https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1034222 Thanks for your time.