From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephan Diestelhorst Subject: Re: [PATCH] SATA / AHCI: Do not play with the link PM during suspend to RAM Date: Tue, 17 Aug 2010 14:10:20 +0200 Message-ID: <201008171410.21382.stephan.diestelhorst@amd.com> References: <201007091750.05020.stephan.diestelhorst@amd.com> <201008171319.25080.rjw@sisk.pl> <4C6A7281.3030804@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Return-path: Received: from tx2ehsobe002.messaging.microsoft.com ([65.55.88.12]:51029 "EHLO TX2EHSOBE004.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751379Ab0HQMKc (ORCPT ); Tue, 17 Aug 2010 08:10:32 -0400 In-Reply-To: <4C6A7281.3030804@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: "Rafael J. Wysocki" , "linux-kernel@vger.kernel.org" , "linux-ide@vger.kernel.org" , "linux-pm@lists.osdl.org" , Stephan Diestelhorst Hi, On Tuesday 17 August 2010, 13:29:05 Tejun Heo wrote: > Hello, > > On 08/17/2010 01:19 PM, Rafael J. Wysocki wrote: > > Well, I wonder what the real reason for doing the link power management > > thing at this particular point in the suspend code path is. It just seems to > > disable the link power management, but then the controller is put into a > > low-power state and is reset from scratch during resume, so I'm not quite > > sure how skipping that code could possibly lead to any problems. > > > Perhaps we could move the link PM manipulation to the prepare stage > > of suspend? > > Yeah, one possibility is that the devices misbehave if they receive > LPM commands while suspended. Does commenting out sd_suspend resolve > the issue too? If you want me to test anything... let me know. Since I do not know much about the ATA code, I do not know what to change where. (A simple grep for sd_suspend in drivers/ata didn't turn up anything.) Thanks, Stephan -- Stephan Diestelhorst, AMD Operating System Research Center stephan.diestelhorst@amd.com, Tel. +49 (0)351 448 356 719 Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach General Managers: Alberto Bozzo, Andrew Bowd Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632