From patchwork Sun Jan 6 02:48:28 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Lu X-Patchwork-Id: 209722 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 88DF52C0082 for ; Sun, 6 Jan 2013 13:48:44 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755956Ab3AFCsj (ORCPT ); Sat, 5 Jan 2013 21:48:39 -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 S1755625Ab3AFCsg (ORCPT ); Sat, 5 Jan 2013 21:48:36 -0500 Received: from azsmga002.ch.intel.com ([10.2.17.35]) by azsmga101.ch.intel.com with ESMTP; 05 Jan 2013 18:48:35 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,417,1355126400"; d="scan'208";a="188108663" Received: from aaronlu.sh.intel.com ([10.239.36.111]) by AZSMGA002.ch.intel.com with ESMTP; 05 Jan 2013 18:48:33 -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 8/9] libata: no poll when ODD is powered off Date: Sun, 6 Jan 2013 10:48:28 +0800 Message-Id: <1357440509-28108-9-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-ide-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org When the ODD is powered off, any action the user did to the ODD that would generate a media event will trigger an ACPI interrupt, so the poll for media event is no longer necessary. And the poll will also cause a runtime status change, which will stop the ODD from staying in powered off state, so the poll should better be stopped. But since we don't have access to the gendisk structure in LLDs, here comes the event_driven flag for scsi device. This flag serves as a capability of the device, conveyed by the LLDs to upper layer. It is set when LLDs know that this device will no longer generate any media related events, so that the check_events can simply return 0 without bothering the device, effectively silence the poll. Signed-off-by: Aaron Lu --- drivers/ata/libata-zpodd.c | 8 ++++++++ drivers/scsi/sr.c | 6 +++++- include/scsi/scsi_device.h | 1 + 3 files changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/ata/libata-zpodd.c b/drivers/ata/libata-zpodd.c index 3c39987..5843a18 100644 --- a/drivers/ata/libata-zpodd.c +++ b/drivers/ata/libata-zpodd.c @@ -177,6 +177,13 @@ void zpodd_pre_poweroff(struct ata_device *dev) { struct zpodd *zpodd = dev->zpodd; + /* + * Silence the media change poll, as we will be notified when + * user wants to use the ODD so there is no meaning to poll + * it when it is powered off + */ + dev->sdev->event_driven = true; + zpodd->powered_off = true; device_set_run_wake(&dev->sdev->sdev_gendev, true); acpi_pm_device_run_wake(&dev->sdev->sdev_gendev, true); @@ -209,6 +216,7 @@ void zpodd_post_resume(struct ata_device *dev) zpodd->last_ready = 0; zpodd->zp_ready = false; + dev->sdev->event_driven = false; } static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context) diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 4d1a610..b034274 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -594,7 +594,11 @@ static unsigned int sr_block_check_events(struct gendisk *disk, unsigned int clearing) { struct scsi_cd *cd = scsi_cd(disk); - return cdrom_check_events(&cd->cdi, clearing); + + if (!cd->device->event_driven) + return cdrom_check_events(&cd->cdi, clearing); + else + return 0; } static int sr_block_revalidate_disk(struct gendisk *disk) diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index e65c62e..1756151 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -160,6 +160,7 @@ struct scsi_device { unsigned can_power_off:1; /* Device supports runtime power off */ unsigned wce_default_on:1; /* Cache is ON by default */ unsigned no_dif:1; /* T10 PI (DIF) should be disabled */ + unsigned event_driven:1; /* No need to poll the device */ DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */ struct list_head event_list; /* asserted events */