From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757502Ab2INOk4 (ORCPT ); Fri, 14 Sep 2012 10:40:56 -0400 Received: from cavan.codon.org.uk ([93.93.128.6]:60309 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751543Ab2INOkz (ORCPT ); Fri, 14 Sep 2012 10:40:55 -0400 Date: Fri, 14 Sep 2012 15:40:49 +0100 From: Matthew Garrett To: David Woodhouse Cc: Grant Likely , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Daniel Vetter , David Airlie Subject: Re: [PATCH] i915: Quirk out disconnected backlight Message-ID: <20120914144049.GB8195@srcf.ucam.org> References: <1347627426-3813-1-git-send-email-grant.likely@secretlab.ca> <20120914134853.GA6533@srcf.ucam.org> <1347632954.21322.44.camel@shinybook.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1347632954.21322.44.camel@shinybook.infradead.org> User-Agent: Mutt/1.5.20 (2009-06-14) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: mjg59@cavan.codon.org.uk X-SA-Exim-Scanned: No (on cavan.codon.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 14, 2012 at 03:29:14PM +0100, David Woodhouse wrote: > On Fri, 2012-09-14 at 14:48 +0100, Matthew Garrett wrote: > > On Fri, Sep 14, 2012 at 01:57:06PM +0100, Grant Likely wrote: > > > > > Tested on MacbookPro8,3. Without this patch both the intel_backlight and > > > gmux_backlight devices get registered and userspace doesn't know which > > > it should use. > > > > Userspace should be figuring out which one to use from the type field. > > It only does that if it's using gsd-backlight-helper to poke > at /sys/class/backlight directly. If X exposes a backlight, (as it does > for the Intel backlight), then gsd will just use that. Yeah, X should be doing the same. If it's not then it's broken. OTOH, I do agree that if we already know that we can't do anything with the backlight (as is clearly the case if the PWM field is 0) we should just disable it. -- Matthew Garrett | mjg59@srcf.ucam.org