From patchwork Sun Jan 6 02:48:29 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Lu X-Patchwork-Id: 1936931 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id E4309400F6 for ; Sun, 6 Jan 2013 02:48:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755168Ab3AFCsk (ORCPT ); Sat, 5 Jan 2013 21:48:40 -0500 Received: from mga03.intel.com ([143.182.124.21]:43075 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755935Ab3AFCsi (ORCPT ); Sat, 5 Jan 2013 21:48:38 -0500 Received: from azsmga002.ch.intel.com ([10.2.17.35]) by azsmga101.ch.intel.com with ESMTP; 05 Jan 2013 18:48:37 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,417,1355126400"; d="scan'208";a="188108669" Received: from aaronlu.sh.intel.com ([10.239.36.111]) by AZSMGA002.ch.intel.com with ESMTP; 05 Jan 2013 18:48:35 -0800 From: Aaron Lu To: Jeff Garzik , James Bottomley , "Rafael J. Wysocki" , Alan Stern , Tejun Heo Cc: Aaron Lu , Jeff Wu , linux-ide@vger.kernel.org, linux-pm@vger.kernel.org, linux-scsi@vger.kernel.org, linux-acpi@vger.kernel.org, Aaron Lu Subject: [PATCH v11 9/9] libata: do not suspend port if normal ODD is attached Date: Sun, 6 Jan 2013 10:48:29 +0800 Message-Id: <1357440509-28108-10-git-send-email-aaron.lu@intel.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1357440509-28108-1-git-send-email-aaron.lu@intel.com> References: <1357440509-28108-1-git-send-email-aaron.lu@intel.com> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org For ODDs, the upper layer will poll for media change every a few seconds, which will make it enter and leave suspend state very oftern. And as each suspend will also cause a hard/soft reset, the gain of runtime suspend is very little while the ODD may mis-function after constantly being reset. So the idle callback here will not proceed to suspend if a non-ZPODD capable ODD is attached to the port. Signed-off-by: Aaron Lu --- drivers/ata/libata-core.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 65a362e..f664a90 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -5408,8 +5408,27 @@ static int ata_port_resume(struct device *dev) return rc; } +/* + * For ODDs, the upper layer will poll for media change every a few seconds, + * which will make it enter and leave suspend state every a few seconds. And + * as each suspend will cause a hard/soft reset, the gain of runtime suspend + * is very little and the ODD may mis-function after constantly being reset. + * So the idle callback here will not proceed to suspend if a non-ZPODD capable + * ODD is attached to the port. + */ static int ata_port_runtime_idle(struct device *dev) { + struct ata_port *ap = to_ata_port(dev); + struct ata_link *link; + struct ata_device *adev; + + ata_for_each_link(link, ap, HOST_FIRST) { + ata_for_each_dev(adev, link, ENABLED) + if (adev->class == ATA_DEV_ATAPI && + !zpodd_dev_enabled(adev)) + return -EBUSY; + } + return pm_runtime_suspend(dev); }