From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756865Ab1HaQbf (ORCPT ); Wed, 31 Aug 2011 12:31:35 -0400 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:54026 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756322Ab1HaQbc (ORCPT ); Wed, 31 Aug 2011 12:31:32 -0400 Date: Wed, 31 Aug 2011 17:31:29 +0100 From: Mark Brown To: Arnd Bergmann Cc: Stephen Warren , Ben Dooks , Dilan Lee , "linux-i2c@vger.kernel.org" , "linux-tegra@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Colin Cross Subject: Re: [PATCH] i2c/tegra: I2C driver uses the suspend_noirq/resume_noirq Message-ID: <20110831163129.GY2061@opensource.wolfsonmicro.com> References: <1312586102-27907-1-git-send-email-swarren@nvidia.com> <74CDBE0F657A3D45AFBB94109FB122FF04B3279D4F@HQMAIL01.nvidia.com> <201108311828.40783.arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201108311828.40783.arnd@arndb.de> X-Cookie: You have a truly strong individuality. User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 31, 2011 at 06:28:40PM +0200, Arnd Bergmann wrote: > Sorry, I normally like to give my opinion on everything, but I really don't > have a clue what this one is about. I don't understand i2c or power management ;-) The issue is that due to our sequencing suspend and resume using the control heirachy rather than dependencies we attempt to suspend the I2C controller prior to some devices that need it. As we don't have a good solution for this at the minute where it's an issue we've been avoiding it by using the _noirq() suspend and resume functions for the controller to reorder their suspend with respect to the rest of the system. It's not great but practically speaking it works.