From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: 2.6.30-rc1 (latest git): thinkpad-acpi: cannot control brightness with hotkeys (BISECTED) Date: Wed, 15 Apr 2009 21:01:25 +0100 Message-ID: <20090415200125.GA31483@srcf.ucam.org> References: <49E10684.5090101@gmail.com> <20090411150555.8b13ed18.akpm@linux-foundation.org> <20090412161448.GC26502@khazad-dum.debian.net> <49E234ED.5010105@gmail.com> <1239585695.5564.5.camel@localhost.localdomain> <49E3575A.60204@gmail.com> <20090413203450.GC16152@khazad-dum.debian.net> <49E5234E.5070303@gmail.com> <20090415164939.GA27807@srcf.ucam.org> <49E63BCB.9090801@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from cavan.codon.org.uk ([93.93.128.6]:33732 "EHLO vavatch.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752895AbZDOUBi (ORCPT ); Wed, 15 Apr 2009 16:01:38 -0400 Content-Disposition: inline In-Reply-To: <49E63BCB.9090801@gmail.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Niel Lambrechts Cc: Henrique de Moraes Holschuh , yakui_zhao , Andrew Morton , "linux.kernel" , "linux-acpi@vger.kernel.org" On Wed, Apr 15, 2009 at 09:55:55PM +0200, Niel Lambrechts wrote: > The behaviour seems slightly different from before your 74a365b3f354 > commit in that /sys/class/backlight remains empty until i915 gets loaded > for the first time, the contents then persist even if i915 is unloaded. > Perhaps the directory was populated by a different kernel module, since > when I did the bisect yesterday the directory would be there on boot > before I started X or loaded i915. In the past the directory would be created when the acpi video driver was loaded, but probably wouldn't work. Doing it that way is a violation of the opregion spec and causes some machines to break in a horrible manner, so I'd prefer not to go back to that version... > I'm not sure if that matters to any other user-space app. (or if > ideally one is supposed to be able to control brightness in the console > without having to load i915), but it's fine for controlling brightness > in Xorg. If you use modesetting then you shouldn't need to launch X to get working brightness control. The problem with the old-style world is that you won't get interrupts until X comes up. -- Matthew Garrett | mjg59@srcf.ucam.org