Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932706Ab1DMAF1 (ORCPT ); Tue, 12 Apr 2011 20:05:27 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:41656 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932282Ab1DMAF0 (ORCPT ); Tue, 12 Apr 2011 20:05:26 -0400 From: "Rafael J. Wysocki" To: Linux PM mailing list Subject: [RFC][PATCH] PM: Make power domain callbacks take precedence over subsystem ones Date: Wed, 13 Apr 2011 02:05:26 +0200 User-Agent: KMail/1.13.6 (Linux/2.6.39-rc3+; KDE/4.6.0; x86_64; ; ) Cc: Kevin Hilman , LKML , Grant Likely , Len Brown , linux-sh@vger.kernel.org, lethal@linux-sh.org, Magnus Damm , Alan Stern MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201104130205.26988.rjw@sisk.pl> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8762 Lines: 266 From: Rafael J. Wysocki Change the PM core's behavior related to power domains in such a way that, if a power domain is defined for a given device, its callbacks will be executed instead of and not in addition to the device subsystem's PM callbacks. The idea behind the initial implementation of power domains handling by the PM core was that power domain callbacks would be executed in addition to subsystem callbacks, so that it would be possible to extend the subsystem callbacks by using power domains. It turns out, however, that this wouldn't be really convenient in some important situations. For example, there are systems in which power can only be removed from entire power domains. On those systems it is not desirable to execute device drivers' PM callbacks until it is known that power is going to be removed from the devices in question, which means that they should be executed by power domain callbacks rather then by subsystem (e.g. bus type) PM callbacks, because subsystems generally have no information about what devices belong to which power domain. Thus, for instance, if the bus type in question is the platform bus type, its PM callbacks generally should not be called in addition to power domain callbacks, because they run device drivers' callbacks unconditionally if defined. While in principle the default subsystem PM callbacks, or a subset of them, may be replaced with different functions, it doesn't seem correct to do so, because that would change the subsystem's behavior with respect to all devices in the system, regardless of whether or not they belong to any power domains. Thus, the only remaining option is to make power domain callbacks take precedence over subsystem callbacks. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/main.c | 64 ++++++++++++++++++++----------------------- drivers/base/power/runtime.c | 29 ++++++------------- 2 files changed, 41 insertions(+), 52 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 @@ -168,7 +168,6 @@ static int rpm_check_suspend_allowed(str static int rpm_idle(struct device *dev, int rpmflags) { int (*callback)(struct device *); - int (*domain_callback)(struct device *); int retval; retval = rpm_check_suspend_allowed(dev); @@ -214,7 +213,9 @@ static int rpm_idle(struct device *dev, dev->power.idle_notification = true; - if (dev->type && dev->type->pm) + if (dev->pwr_domain) + callback = dev->pwr_domain->ops.runtime_idle; + else if (dev->type && dev->type->pm) callback = dev->type->pm->runtime_idle; else if (dev->class && dev->class->pm) callback = dev->class->pm->runtime_idle; @@ -223,19 +224,10 @@ static int rpm_idle(struct device *dev, else callback = NULL; - if (dev->pwr_domain) - domain_callback = dev->pwr_domain->ops.runtime_idle; - else - domain_callback = NULL; - - if (callback || domain_callback) { + if (callback) { spin_unlock_irq(&dev->power.lock); - if (domain_callback) - retval = domain_callback(dev); - - if (!retval && callback) - callback(dev); + callback(dev); spin_lock_irq(&dev->power.lock); } @@ -382,7 +374,9 @@ static int rpm_suspend(struct device *de __update_runtime_status(dev, RPM_SUSPENDING); - if (dev->type && dev->type->pm) + if (dev->pwr_domain) + callback = dev->pwr_domain->ops.runtime_suspend; + else if (dev->type && dev->type->pm) callback = dev->type->pm->runtime_suspend; else if (dev->class && dev->class->pm) callback = dev->class->pm->runtime_suspend; @@ -400,8 +394,6 @@ static int rpm_suspend(struct device *de else pm_runtime_cancel_pending(dev); } else { - if (dev->pwr_domain) - rpm_callback(dev->pwr_domain->ops.runtime_suspend, dev); no_callback: __update_runtime_status(dev, RPM_SUSPENDED); pm_runtime_deactivate_timer(dev); @@ -582,9 +574,8 @@ static int rpm_resume(struct device *dev __update_runtime_status(dev, RPM_RESUMING); if (dev->pwr_domain) - rpm_callback(dev->pwr_domain->ops.runtime_resume, dev); - - if (dev->type && dev->type->pm) + callback = dev->pwr_domain->ops.runtime_resume; + else if (dev->type && dev->type->pm) callback = dev->type->pm->runtime_resume; else if (dev->class && dev->class->pm) callback = dev->class->pm->runtime_resume; Index: linux-2.6/drivers/base/power/main.c =================================================================== --- linux-2.6.orig/drivers/base/power/main.c +++ linux-2.6/drivers/base/power/main.c @@ -425,10 +425,8 @@ static int device_resume_noirq(struct de if (dev->pwr_domain) { pm_dev_dbg(dev, state, "EARLY power domain "); - pm_noirq_op(dev, &dev->pwr_domain->ops, state); - } - - if (dev->type && dev->type->pm) { + error = pm_noirq_op(dev, &dev->pwr_domain->ops, state); + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "EARLY type "); error = pm_noirq_op(dev, dev->type->pm, state); } else if (dev->class && dev->class->pm) { @@ -516,7 +514,8 @@ static int device_resume(struct device * if (dev->pwr_domain) { pm_dev_dbg(dev, state, "power domain "); - pm_op(dev, &dev->pwr_domain->ops, state); + error = pm_op(dev, &dev->pwr_domain->ops, state); + goto End; } if (dev->type && dev->type->pm) { @@ -628,12 +627,11 @@ static void device_complete(struct devic { device_lock(dev); - if (dev->pwr_domain && dev->pwr_domain->ops.complete) { + if (dev->pwr_domain) { pm_dev_dbg(dev, state, "completing power domain "); - dev->pwr_domain->ops.complete(dev); - } - - if (dev->type && dev->type->pm) { + if (dev->pwr_domain->ops.complete) + dev->pwr_domain->ops.complete(dev); + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "completing type "); if (dev->type->pm->complete) dev->type->pm->complete(dev); @@ -731,7 +729,12 @@ static int device_suspend_noirq(struct d { int error; - if (dev->type && dev->type->pm) { + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "LATE power domain "); + error = pm_noirq_op(dev, &dev->pwr_domain->ops, state); + if (error) + return error; + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "LATE type "); error = pm_noirq_op(dev, dev->type->pm, state); if (error) @@ -748,11 +751,6 @@ static int device_suspend_noirq(struct d return error; } - if (dev->pwr_domain) { - pm_dev_dbg(dev, state, "LATE power domain "); - pm_noirq_op(dev, &dev->pwr_domain->ops, state); - } - return 0; } @@ -840,21 +838,27 @@ static int __device_suspend(struct devic goto End; } + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "power domain "); + error = pm_op(dev, &dev->pwr_domain->ops, state); + goto End; + } + if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "type "); error = pm_op(dev, dev->type->pm, state); - goto Domain; + goto End; } if (dev->class) { if (dev->class->pm) { pm_dev_dbg(dev, state, "class "); error = pm_op(dev, dev->class->pm, state); - goto Domain; + goto End; } else if (dev->class->suspend) { pm_dev_dbg(dev, state, "legacy class "); error = legacy_suspend(dev, state, dev->class->suspend); - goto Domain; + goto End; } } @@ -868,12 +872,6 @@ static int __device_suspend(struct devic } } - Domain: - if (!error && dev->pwr_domain) { - pm_dev_dbg(dev, state, "power domain "); - pm_op(dev, &dev->pwr_domain->ops, state); - } - End: device_unlock(dev); complete_all(&dev->power.completion); @@ -964,7 +962,14 @@ static int device_prepare(struct device device_lock(dev); - if (dev->type && dev->type->pm) { + if (dev->pwr_domain) { + pm_dev_dbg(dev, state, "preparing power domain "); + if (dev->pwr_domain->ops.prepare) + error = dev->pwr_domain->ops.prepare(dev); + suspend_report_result(dev->pwr_domain->ops.prepare, error); + if (error) + goto End; + } else if (dev->type && dev->type->pm) { pm_dev_dbg(dev, state, "preparing type "); if (dev->type->pm->prepare) error = dev->type->pm->prepare(dev); @@ -983,13 +988,6 @@ static int device_prepare(struct device if (dev->bus->pm->prepare) error = dev->bus->pm->prepare(dev); suspend_report_result(dev->bus->pm->prepare, error); - if (error) - goto End; - } - - if (dev->pwr_domain && dev->pwr_domain->ops.prepare) { - pm_dev_dbg(dev, state, "preparing power domain "); - dev->pwr_domain->ops.prepare(dev); } End: -- 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/