From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerone Young Subject: Re: [Intel-gfx] [RFC PATCH 0/2] i915 brightness control Date: Sat, 05 Jun 2010 03:47:39 +0800 Message-ID: <1275680859.1828.1161.camel@laptop> References: <1275516702-27090-1-git-send-email-kamal@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from adelie.canonical.com ([91.189.90.139]:60519 "EHLO adelie.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754036Ab0FDTrq (ORCPT ); Fri, 4 Jun 2010 15:47:46 -0400 In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Pedro Ribeiro Cc: Kamal Mostafa , linux-acpi@vger.kernel.org, intel-gfx@lists.freedesktop.org On Thu, 2010-06-03 at 00:20 +0100, Pedro Ribeiro wrote: > On 2 June 2010 23:11, Kamal Mostafa wrote: > > Requesting comments on this idea (proposed by Matthew Garrett) and my > > implementation. Note especially the KNOWN PROBLEM with a "GM45" GPU. > > > > -Kamal > > > > ....... > > > > BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/568611 > > > > In order to avoid the often-dysfunctional native acpi brightness control > > methods, a new acpi_brightness_hook interface is made available. > > > > The i915 driver uses the new hook to take over brightness control. > > Boot with i915.brightness=0 to disable. > > > > KNOWN PROBLEM: > > - i915 opregion brightness control silently fails on GM45 (pci-id 0x2a42) > > > > [RFC PATCH 1/2] acpi/video: acpi_brightness_hook API > > [RFC PATCH 2/2] drm/i915: override acpi brightness control > > > > _______________________________________________ > > Intel-gfx mailing list > > Intel-gfx@lists.freedesktop.org > > http://lists.freedesktop.org/mailman/listinfo/intel-gfx > > > > Are you sure this is a good idea to enable it by default just because > of a problem with one manufacturer (Dell)? This issue is with many manufactures. From this bug you can see HP machines are effected also. https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/568611 > > My Lenovo laptop has fine brightness control with a GM45 and this may break it. > Might be safer only to enable it for laptops with known problems. > > > Regards, > Pedro > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html