Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752666Ab1FYW4b (ORCPT ); Sat, 25 Jun 2011 18:56:31 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:58327 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752575Ab1FYW41 (ORCPT ); Sat, 25 Jun 2011 18:56:27 -0400 From: "Rafael J. Wysocki" To: Linux PM mailing list Subject: [PATCH 2/3] PM / Runtime: Return special error code if runtime PM is disabled Date: Sun, 26 Jun 2011 00:55:52 +0200 User-Agent: KMail/1.13.6 (Linux/3.0.0-rc4+; KDE/4.6.0; x86_64; ; ) Cc: Tejun Heo , Alan Stern , Greg KH , LKML , Magnus Damm , Kevin Hilman , linux-scsi@vger.kernel.org References: <201106260054.20578.rjw@sisk.pl> In-Reply-To: <201106260054.20578.rjw@sisk.pl> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201106260055.52859.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4321 Lines: 112 From: Rafael J. Wysocki Some callers of pm_runtime_get_sync() and other runtime PM helper functions, scsi_autopm_get_host() and scsi_autopm_get_device() in particular, need to distinguish error codes returned when runtime PM is disabled (i.e. power.disable_depth is nonzero for the given device) from error codes returned in other situations. For this reason, make the runtime PM helper functions return -EACCES when power.disable_depth is nonzero and ensure that this error code won't be returned by them in any other circumstances. Modify scsi_autopm_get_host() and scsi_autopm_get_device() to check the error code returned by pm_runtime_get_sync() and ignore -EACCES. Signed-off-by: Rafael J. Wysocki --- Documentation/power/runtime_pm.txt | 6 ++++-- drivers/base/power/runtime.c | 9 +++++---- drivers/scsi/scsi_pm.c | 8 ++++---- 3 files changed, 13 insertions(+), 10 deletions(-) Index: linux-2.6/drivers/base/power/runtime.c =================================================================== --- linux-2.6.orig/drivers/base/power/runtime.c +++ linux-2.6/drivers/base/power/runtime.c @@ -135,8 +135,9 @@ static int rpm_check_suspend_allowed(str if (dev->power.runtime_error) retval = -EINVAL; - else if (atomic_read(&dev->power.usage_count) > 0 - || dev->power.disable_depth > 0) + else if (dev->power.disable_depth > 0) + retval = -EACCES; + else if (atomic_read(&dev->power.usage_count) > 0) retval = -EAGAIN; else if (!pm_children_suspended(dev)) retval = -EBUSY; @@ -262,7 +263,7 @@ static int rpm_callback(int (*cb)(struct spin_lock_irq(&dev->power.lock); } dev->power.runtime_error = retval; - return retval; + return retval != -EACCES ? retval : -EIO; } /** @@ -458,7 +459,7 @@ static int rpm_resume(struct device *dev if (dev->power.runtime_error) retval = -EINVAL; else if (dev->power.disable_depth > 0) - retval = -EAGAIN; + retval = -EACCES; if (retval) goto out; Index: linux-2.6/drivers/scsi/scsi_pm.c =================================================================== --- linux-2.6.orig/drivers/scsi/scsi_pm.c +++ linux-2.6/drivers/scsi/scsi_pm.c @@ -144,9 +144,9 @@ int scsi_autopm_get_device(struct scsi_d int err; err = pm_runtime_get_sync(&sdev->sdev_gendev); - if (err < 0) + if (err < 0 && err !=-EACCES) pm_runtime_put_sync(&sdev->sdev_gendev); - else if (err > 0) + else err = 0; return err; } @@ -173,9 +173,9 @@ int scsi_autopm_get_host(struct Scsi_Hos int err; err = pm_runtime_get_sync(&shost->shost_gendev); - if (err < 0) + if (err < 0 && err !=-EACCES) pm_runtime_put_sync(&shost->shost_gendev); - else if (err > 0) + else err = 0; return err; } Index: linux-2.6/Documentation/power/runtime_pm.txt =================================================================== --- linux-2.6.orig/Documentation/power/runtime_pm.txt +++ linux-2.6/Documentation/power/runtime_pm.txt @@ -291,7 +291,8 @@ drivers/base/power/runtime.c and include - execute the subsystem-level suspend callback for the device; returns 0 on success, 1 if the device's run-time PM status was already 'suspended', or error code on failure, where -EAGAIN or -EBUSY means it is safe to attempt - to suspend the device again in future + to suspend the device again in future and -EACCES means that disable_depth + is different from 0 int pm_runtime_autosuspend(struct device *dev); - same as pm_runtime_suspend() except that the autosuspend delay is taken @@ -304,7 +305,8 @@ drivers/base/power/runtime.c and include success, 1 if the device's run-time PM status was already 'active' or error code on failure, where -EAGAIN means it may be safe to attempt to resume the device again in future, but 'power.runtime_error' should be - checked additionally + checked additionally, and -EACCES means that disable_depth is different + from 0 int pm_request_idle(struct device *dev); - submit a request to execute the subsystem-level idle callback for the -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/