From patchwork Thu Apr 28 23:54:55 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rafael Wysocki X-Patchwork-Id: 740132 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.3) with ESMTP id p3SNud1s032355 for ; Thu, 28 Apr 2011 23:56:40 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758235Ab1D1X4J (ORCPT ); Thu, 28 Apr 2011 19:56:09 -0400 Received: from ogre.sisk.pl ([217.79.144.158]:33824 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758167Ab1D1Xzy (ORCPT ); Thu, 28 Apr 2011 19:55:54 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by ogre.sisk.pl (Postfix) with ESMTP id 993EA1AD390; Fri, 29 Apr 2011 01:52:39 +0200 (CEST) Received: from ogre.sisk.pl ([127.0.0.1]) by localhost (ogre.sisk.pl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 30942-09; Fri, 29 Apr 2011 01:52:14 +0200 (CEST) Received: from ferrari.rjw.lan (220-bem-13.acn.waw.pl [82.210.184.220]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ogre.sisk.pl (Postfix) with ESMTP id 1BE8D1AD3EF; Fri, 29 Apr 2011 01:52:14 +0200 (CEST) From: "Rafael J. Wysocki" To: Linux PM mailing list Subject: [RFC][PATCH 1/2] PM / Runtime: Support for generic I/O power domains Date: Fri, 29 Apr 2011 01:54:55 +0200 User-Agent: KMail/1.13.6 (Linux/2.6.39-rc5+; KDE/4.6.0; x86_64; ; ) Cc: Greg KH , LKML , Kevin Hilman , Grant Likely , Magnus Damm , linux-sh@vger.kernel.org References: <201104290154.12966.rjw@sisk.pl> In-Reply-To: <201104290154.12966.rjw@sisk.pl> MIME-Version: 1.0 Message-Id: <201104290154.56145.rjw@sisk.pl> X-Virus-Scanned: amavisd-new at ogre.sisk.pl using MkS_Vir for Linux Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.41]); Thu, 28 Apr 2011 23:56:40 +0000 (UTC) From: Rafael J. Wysocki Introcude common headers, helper functions and callbacks allowing platforms to use simple generic power domains for runtime power management. Introduce struct generic_power_domain to be used for representing power domains that each contain a number of devices and may be master domains or subdomains with respect to other power domains. Among other things, this structure includes callbacks to be provided by platforms for performing specific tasks related to power management (i.e. ->stop_device() may disable a device's clocks, while ->start_device() may enable them, ->power_on() is supposed to remove power from the entire power domain and ->power_off() is supposed to restore it). Introduce functions that can be used as power domain runtime PM callbacks, pm_genpd_runtime_suspend() and pm_genpd_runtime_resume(), as well as helper functions for the initialization of a power domain represented by a struct generic_power_domain object, adding a device to or removing a device from it and adding or removing subdomains. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/Makefile | 2 drivers/base/power/domain.c | 416 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/pm.h | 3 include/linux/pm_domain.h | 82 ++++++++ 4 files changed, 501 insertions(+), 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux-2.6/include/linux/pm_domain.h =================================================================== --- /dev/null +++ linux-2.6/include/linux/pm_domain.h @@ -0,0 +1,82 @@ +/* + * pm_domain.h - Definitions and headers related to device power domains. + * + * Copyright (C) 2011 Rafael J. Wysocki , Renesas Electronics Corp. + * + * This file is released under the GPLv2. + */ + +#ifndef _LINUX_PM_DOMAIN_H +#define _LINUX_PM_DOMAIN_H + +#include + +struct dev_power_governor { + bool (*power_down_ok)(struct dev_power_domain *domain); +}; + +struct generic_power_domain { + struct dev_power_domain domain; + struct list_head node; + struct generic_power_domain *master; + struct list_head subdomain_list; + struct list_head device_list; + struct mutex lock; + struct dev_power_governor *gov; + bool power_is_off; + int (*power_off)(struct dev_power_domain *domain); + int (*power_on)(struct dev_power_domain *domain); + int (*start_device)(struct device *dev); + int (*stop_device)(struct device *dev); +}; + +struct dev_list_entry { + struct list_head node; + struct device *dev; +}; + +#ifdef CONFIG_PM_RUNTIME +extern int pm_genpd_runtime_suspend(struct device *dev); +extern int pm_genpd_runtime_resume(struct device *dev); +#else +#define pm_genpd_runtime_suspend NULL; +#define pm_genpd_runtime_resume NULL; +#endif + +#ifdef CONFIG_PM +extern int pm_genpd_add_device(struct generic_power_domain *genpd, + struct device *dev); +extern int pm_genpd_remove_device(struct generic_power_domain *genpd, + struct device *dev); +extern int pm_genpd_add_subdomain(struct generic_power_domain *genpd, + struct generic_power_domain *new_subdomain); +extern int pm_genpd_remove_subdomain(struct generic_power_domain *genpd, + struct generic_power_domain *target); +extern void pm_genpd_init(struct generic_power_domain *genpd, + struct dev_power_governor *gov, bool is_off); +#else +static inline int pm_genpd_add_device(struct generic_power_domain *genpd, + struct device *dev) +{ + return -ENOSYS; +} +static inline int pm_genpd_remove_device(struct generic_power_domain *genpd, + struct device *dev) +{ + return -ENOSYS; +} +static inline int pm_genpd_add_subdomain(struct generic_power_domain *genpd, + struct generic_power_domain *new_sd) +{ + return -ENOSYS; +} +static inline int pm_genpd_remove_subdomain(struct generic_power_domain *genpd, + struct generic_power_domain *target) +{ + return -ENOSYS; +} +static inline void pm_genpd_init(struct generic_power_domain *genpd, + struct dev_power_governor *gov, bool is_off) {} +#endif + +#endif /* _LINUX_PM_DOMAIN_H */ Index: linux-2.6/include/linux/pm.h =================================================================== --- linux-2.6.orig/include/linux/pm.h +++ linux-2.6/include/linux/pm.h @@ -472,7 +472,8 @@ extern void update_pm_runtime_accounting * subsystem-level and driver-level callbacks. */ struct dev_power_domain { - struct dev_pm_ops ops; + struct dev_pm_ops ops; + void *platform_data; }; /* Index: linux-2.6/drivers/base/power/Makefile =================================================================== --- linux-2.6.orig/drivers/base/power/Makefile +++ linux-2.6/drivers/base/power/Makefile @@ -1,4 +1,4 @@ -obj-$(CONFIG_PM) += sysfs.o generic_ops.o +obj-$(CONFIG_PM) += sysfs.o generic_ops.o domain.o obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o obj-$(CONFIG_PM_RUNTIME) += runtime.o obj-$(CONFIG_PM_TRACE_RTC) += trace.o Index: linux-2.6/drivers/base/power/domain.c =================================================================== --- /dev/null +++ linux-2.6/drivers/base/power/domain.c @@ -0,0 +1,416 @@ +/* + * drivers/base/power/domain.c - Common code related to device power domains. + * + * Copyright (C) 2011 Rafael J. Wysocki , Renesas Electronics Corp. + * + * This file is released under the GPLv2. + */ + +#include +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_PM_RUNTIME + +/** + * __pm_genpd_restore_device - Restore a pre-suspend state of a device. + * @dev: Device to restore the state of. + * @genpd: Power domain the device belongs to. + */ +static void __pm_genpd_restore_device(struct device *dev, + struct generic_power_domain *genpd) +{ + struct device_driver *drv = dev->driver; + + if (genpd->start_device) + genpd->start_device(dev); + + if (drv && drv->pm && drv->pm->runtime_resume) + drv->pm->runtime_resume(dev); + + if (genpd->stop_device) + genpd->stop_device(dev); +} + +/** + * __pm_genpd_poweroff - Remove power from a given power domain. + * @genpd: Power domain to power down. + * + * If all of the @genpd's devices have been suspended and all of its subdomains + * have been powered down, run the runtime suspend callbacks provided by all of + * the @genpd's devices' drivers and remove power from @genpd. + */ +static int __pm_genpd_poweroff(struct generic_power_domain *genpd) +{ + struct generic_power_domain *subdomain; + struct dev_list_entry *dle; + int ret; + + if (genpd->power_is_off) + return 0; + + list_for_each_entry(dle, &genpd->device_list, node) + if (!pm_runtime_suspended(dle->dev)) + return -EBUSY; + + list_for_each_entry_reverse(subdomain, &genpd->subdomain_list, node) { + mutex_lock(&subdomain->lock); + ret = __pm_genpd_poweroff(subdomain); + mutex_unlock(&subdomain->lock); + if (ret) + return ret; + } + + if (genpd->gov && genpd->gov->power_down_ok) { + if (!genpd->gov->power_down_ok(&genpd->domain)) + return -EAGAIN; + } + + list_for_each_entry_reverse(dle, &genpd->device_list, node) { + struct device *dev = dle->dev; + struct device_driver *drv = dev->driver; + + if (genpd->start_device) + genpd->start_device(dev); + + if (drv && drv->pm && drv->pm->runtime_suspend) + ret = drv->pm->runtime_suspend(dev); + + if (genpd->stop_device) + genpd->stop_device(dev); + + if (ret) + goto err_dev; + } + + if (genpd->power_off) + genpd->power_off(&genpd->domain); + + genpd->power_is_off = true; + + return 0; + + err_dev: + list_for_each_entry_continue(dle, &genpd->device_list, node) + __pm_genpd_restore_device(dle->dev, genpd); + + return ret; +} + +/** + * pm_genpd_poweroff - Remove power from a given power domain and its masters. + * @genpd: Power domain to power down. + * + * Try to remove power from @genpd and all of its masters in order to save as + * much power as possible. + */ +static int pm_genpd_poweroff(struct generic_power_domain *genpd) +{ + struct generic_power_domain *master; + int ret; + + mutex_lock(&genpd->lock); + master = genpd->master; + if (master) { + mutex_unlock(&genpd->lock); + return pm_genpd_poweroff(master); + } + ret = __pm_genpd_poweroff(genpd); + mutex_unlock(&genpd->lock); + + return ret; +} + +/** + * pm_genpd_runtime_suspend - Suspend a device belonging to I/O power domain. + * @dev: Device to suspend. + * + * Carry out a runtime suspend of a device under the assumption that its + * pwr_domain field points to the domain member of an object of type + * struct generic_power_domain representing a power domain consisting of I/O + * devices. + */ +int pm_genpd_runtime_suspend(struct device *dev) +{ + struct generic_power_domain *genpd; + + dev_dbg(dev, "%s()\n", __func__); + + if (IS_ERR_OR_NULL(dev->pwr_domain)) + return -EINVAL; + + genpd = container_of(dev->pwr_domain, + struct generic_power_domain, domain); + + if (genpd->stop_device) { + int ret = genpd->stop_device(dev); + if (ret) + return ret; + } + + return pm_genpd_poweroff(genpd); +} + +/** + * __pm_genpd_poweron - Restore power for a given power domain. + * @genpd: Power domain to power up. + * + * Restore power for @genpd and run runtime resume callbacks provided by all of + * its devices' drivers. + */ +static int __pm_genpd_poweron(struct generic_power_domain *genpd) +{ + struct dev_list_entry *dle; + + if (!genpd->power_is_off) + return 0; + + if (genpd->power_on) { + int ret = genpd->power_on(&genpd->domain); + if (ret) + return ret; + } + + genpd->power_is_off = false; + + list_for_each_entry(dle, &genpd->device_list, node) + __pm_genpd_restore_device(dle->dev, genpd); + + return 0; +} + +/** + * pm_genpd_poweron - Restore power for a given power domain and its masters. + * @genpd: Power domain to power up. + * + * Restore power for @genpd and all of its masters so that it is possible to + * resume a device belonging to it. + */ +static int pm_genpd_poweron(struct generic_power_domain *genpd) +{ + struct generic_power_domain *master; + int ret; + + mutex_lock(&genpd->lock); + master = genpd->master; + if (master) { + mutex_unlock(&genpd->lock); + + ret = pm_genpd_poweron(master); + if (ret) + return ret; + + mutex_lock(&genpd->lock); + } + ret = __pm_genpd_poweron(genpd); + mutex_unlock(&genpd->lock); + + return ret; +} + +/** + * pm_genpd_runtime_resume - Resume a device belonging to I/O power domain. + * @dev: Device to suspend. + * + * Carry out a runtime resume of a device under the assumption that its + * pwr_domain field points to the domain member of an object of type + * struct generic_power_domain representing a power domain consisting of I/O + * devices. + */ +int pm_genpd_runtime_resume(struct device *dev) +{ + struct generic_power_domain *genpd; + int ret; + + dev_dbg(dev, "%s()\n", __func__); + + if (IS_ERR_OR_NULL(dev->pwr_domain)) + return -EINVAL; + + genpd = container_of(dev->pwr_domain, + struct generic_power_domain, domain); + + ret = pm_genpd_poweron(genpd); + if (ret) + return ret; + + if (genpd->start_device) + genpd->start_device(dev); + + return 0; +} + +#endif /* CONFIG_PM_RUNTIME */ + +/** + * pm_genpd_add_device - Add a device to an I/O power domain. + * @genpd: Power domain to add the device to. + * @dev: Device to be added. + */ +int pm_genpd_add_device(struct generic_power_domain *genpd, struct device *dev) +{ + struct dev_list_entry *dle; + int ret = 0; + + dev_dbg(dev, "%s()\n", __func__); + + if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev)) + return -EINVAL; + + mutex_lock(&genpd->lock); + + list_for_each_entry(dle, &genpd->device_list, node) + if (dle->dev == dev) { + ret = -EINVAL; + goto out; + } + + dle = kzalloc(sizeof(*dle), GFP_KERNEL); + if (!dle) { + ret = -ENOMEM; + goto out; + } + + dle->dev = dev; + list_add_tail(&dle->node, &genpd->device_list); + + spin_lock_irq(&dev->power.lock); + dev->pwr_domain = &genpd->domain; + spin_unlock_irq(&dev->power.lock); + + out: + mutex_unlock(&genpd->lock); + + return ret; +} + +/** + * pm_genpd_remove_device - Remove a device from an I/O power domain. + * @genpd: Power domain to remove the device from. + * @dev: Device to be removed. + */ +int pm_genpd_remove_device(struct generic_power_domain *genpd, + struct device *dev) +{ + struct dev_list_entry *dle; + int ret = -EINVAL; + + dev_dbg(dev, "%s()\n", __func__); + + if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev)) + return -EINVAL; + + mutex_lock(&genpd->lock); + + list_for_each_entry(dle, &genpd->device_list, node) { + if (dle->dev != dev) + continue; + + spin_lock_irq(&dev->power.lock); + dev->pwr_domain = NULL; + spin_unlock_irq(&dev->power.lock); + + list_del(&dle->node); + kfree(dle); + + ret = 0; + break; + } + + mutex_unlock(&genpd->lock); + + return ret; +} + +/** + * pm_genpd_add_subdomain - Add a subdomain to an I/O power domain. + * @genpd: Master power domain to add the subdomain to. + * @new_subdomain: Subdomain to be added. + */ +int pm_genpd_add_subdomain(struct generic_power_domain *genpd, + struct generic_power_domain *new_subdomain) +{ + struct generic_power_domain *subdomain; + int ret = 0; + + if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(new_subdomain)) + return -EINVAL; + + mutex_lock(&genpd->lock); + + list_for_each_entry(subdomain, &genpd->subdomain_list, node) + if (subdomain == new_subdomain) { + ret = -EINVAL; + goto out; + } + + mutex_lock(&new_subdomain->lock); + list_add_tail(&new_subdomain->node, &genpd->subdomain_list); + new_subdomain->master = genpd; + mutex_unlock(&new_subdomain->lock); + + out: + mutex_unlock(&genpd->lock); + + return ret; +} + +/** + * pm_genpd_remove_subdomain - Remove a subdomain from an I/O power domain. + * @genpd: Master power domain to remove the subdomain from. + * @target: Subdomain to be removed. + */ +int pm_genpd_remove_subdomain(struct generic_power_domain *genpd, + struct generic_power_domain *target) +{ + struct generic_power_domain *subdomain; + int ret = -EINVAL; + + if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(target)) + return -EINVAL; + + mutex_lock(&genpd->lock); + + list_for_each_entry(subdomain, &genpd->subdomain_list, node) { + if (subdomain != target) + continue; + + mutex_lock(&subdomain->lock); + list_del(&subdomain->node); + subdomain->master = NULL; + mutex_unlock(&subdomain->lock); + + ret = 0; + break; + } + + mutex_unlock(&genpd->lock); + + return ret; +} + +/** + * pm_genpd_init - Initialize an I/O power domain object. + * @genpd: Power domain object to initialize. + */ +void pm_genpd_init(struct generic_power_domain *genpd, + struct dev_power_governor *gov, bool is_off) +{ + if (IS_ERR_OR_NULL(genpd)) + return; + + INIT_LIST_HEAD(&genpd->node); + genpd->master = NULL; + INIT_LIST_HEAD(&genpd->device_list); + INIT_LIST_HEAD(&genpd->subdomain_list); + mutex_init(&genpd->lock); + genpd->gov = gov; + genpd->power_is_off = is_off; + genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend; + genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume; + genpd->domain.ops.runtime_idle = pm_generic_runtime_idle; +}