From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guillaume Millet Subject: Re: 8086:2a42 [Asus UL80VT] Backlight control does not work with Intel integrated card, but there are entries in /sys/class/backlight Date: Tue, 03 Dec 2013 11:10:36 +0100 Message-ID: <529DAE1C.1060501@crans.org> References: <529CBB15.7000904@crans.org> <529D5D36.3000101@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from redisdead.crans.org ([138.231.136.39]:35803 "EHLO redisdead.crans.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751496Ab3LCKKm (ORCPT ); Tue, 3 Dec 2013 05:10:42 -0500 In-Reply-To: <529D5D36.3000101@intel.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Aaron Lu Cc: ACPI Devel Mailing List Le 03/12/2013 05:25, Aaron Lu a =C3=A9crit : > On 12/03/2013 12:53 AM, Guillaume Millet wrote: >> Hello, I report an issue, in attempting to follow the instructions a= t >> https://wiki.ubuntu.com/Bugs/Upstream/kernel#KernelTeam.2BAC8-Kernel= TeamBugPolicies.Overview_on_Reporting_Bugs_Upstream >> >> [1.] 8086:2a42 [Asus UL80VT] Backlight control does not work with In= tel >> integrated card, but there are entries in /sys/class/backlight >> >> [2.] The screen brightness control has apparently never worked >> off-the-shelf on this laptop, Asus UL80VT-A1, which is an NVIDIA Opt= imus >> laptop (2 graphic cards). The use of the discrete Nvidia card is man= aged >> by Bumblebee (https://wiki.ubuntu.com/Bumblebee). It used to work wi= th >> the workaround suggested at >> http://wiki.daviddarts.com/Ubuntu_Maverick_on_the_Asus_UL30VT#Screen= _Brightness =20 >> which modifies asus-brn-down.sh to use the "setpci" method. >> Hotkeys are detected, showkey -s returns 0xe0 0x4c 0xe0 0xcc for Fn+= =465 >> and 0xe0 0x54 0xe0 0xd4 for Fn+F6. >> When the hotkeys are triggered, there is no brightness change but th= e >> KDE notification pops up with 3 or 4 levels. >> >> [X.] Other notes >> $ ls /sys/class/backlight/ >> acpi_video0 acpi_video1 intel_backlight >> >> $ cat /sys/class/backlight/intel_backlight/max_brightness >> 2583660 >> >> $ cat /sys/class/backlight/intel_backlight/brightness >> 121584 > With v3.12, does the intel_backlight interface work? > You can verify this by echoing some value to the brightness file and = see > if it has any effect. The value can be echoed is 0 - max_brightness. = Be > careful with very small values, it will black your screen. > > If it works, you can specify intel_backlight as the control interface > for X by creating a xorg.conf file like this: > $ cat /etc/Xorg/Xorg.conf > Section "Device" > Option "Backlight" "intel_backlight" > Identifier "Card0" > Driver "intel" > BusID "PCI:0:2:0" > EndSection The intel_backlight interface does work, by echoing a value between 0=20 and 2583660. The control interface for X also works with that addition in=20 /etc/X11/xorg.conf (Kubuntu). Wow, the issue was immediately solved by posting here. Thanks Aaron Lu! After, (out of curiosity) what should be modified so that X=20 automatically detect the correct control interface, in case of a new=20 installation for example ? -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html