From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752388Ab1IUDuR (ORCPT ); Tue, 20 Sep 2011 23:50:17 -0400 Received: from oproxy9.bluehost.com ([69.89.24.6]:42239 "HELO oproxy9.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751561Ab1IUDuP (ORCPT ); Tue, 20 Sep 2011 23:50:15 -0400 Date: Wed, 21 Sep 2011 09:20:01 +0530 From: Jesse Barnes To: Keith Packard Cc: Dave Airlie , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [Intel-gfx] [PATCH 6/9] drm/i915: Make sure eDP power is on before using aux channel Message-ID: <20110921092001.0b65bd3f@jbarnes-x220> In-Reply-To: <1316470923-27832-7-git-send-email-keithp@keithp.com> References: <1316470923-27832-1-git-send-email-keithp@keithp.com> <1316470923-27832-7-git-send-email-keithp@keithp.com> X-Mailer: Claws Mail 3.7.8 (GTK+ 2.24.6; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Identified-User: {10642:box514.bluehost.com:virtuous:virtuousgeek.org} {sentby:smtp auth 192.55.60.111 authed with jbarnes@virtuousgeek.org} Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 19 Sep 2011 15:22:00 -0700 Keith Packard wrote: > The eDP panel may not be able to respond to aux channel communications > unless it has power supplied. During mode setting, power may be > cut-off during panel power sequencing. Make sure that any aux channel > communications will work by forcing vdd power active as needed. > > This also delays after turning power on and off to ensure that the > panel is keeping up. > > Signed-off-by: Keith Packard This one mixes up lots of cleanups plus the EDID read with the power changes. I'm worried about the VDD smashing as well; we have lots of bugs in the PPS hardware around VDD vs full PPS. We need to make sure appropriate delays are in place when transitioning from one to another. In what paths are we trying to do accesses without power applied? Looks like mainly edid? I see the next patch handles the timing stuff, I assume it's ok. Jesse