From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757864Ab2IGVfJ (ORCPT ); Fri, 7 Sep 2012 17:35:09 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:57797 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751101Ab2IGVfG (ORCPT ); Fri, 7 Sep 2012 17:35:06 -0400 MIME-Version: 1.0 In-Reply-To: <1347031330-19657-1-git-send-email-seth.forshee@canonical.com> References: <1347031330-19657-1-git-send-email-seth.forshee@canonical.com> Date: Fri, 7 Sep 2012 22:35:04 +0100 Message-ID: Subject: Re: [PATCH 0/7] Fixes for hybrid graphics Apple machines From: Dave Airlie To: Seth Forshee Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, David Airlie , Matthew Garrett , Daniel Vetter , Andreas Heider Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 7, 2012 at 4:22 PM, Seth Forshee wrote: > Many hybrid graphics Apple laptops fail to set up LVDS on the secondary > GPU due to missing or incorrect mode information for the panel at init > time. The only way to get the LVDS mode on these machines is via the > DDC, but this is muxed to the active GPU at boot. However, the graphics > mux on these machines supports muxing the i2c idependently of the > display, making it possible for the secondary graphics driver to read > the EDID without a full display switch. > > In order to support this, these patches modify vga_switcheroo to allow > muxing of the DDC idependently of the display. apple-gmux is updated to > support this new functionality, and drm_get_edid() is modified to switch > the DDC mux as needed. > > For this to work we also need to ensure that sufficient switcheroo > suport is available before initializing the secondary GPU. This is done > by adding any non-active GPUs that try to initialize before switcheroo > is ready to a list and initializing these devices once switcheroo > becomes ready. This behavior is restricted to Apple laptops to prevent > causing problems on other machines. I hate this idea, no delaying stuff. We either need to have some sort of enforced ordering or make some stuff only work built-in. But sticking things on a delayed list just in case seems wrong to me. Dave.