From d4f2d87a8b46c14c4307c690c92bd08229f66ecf Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 1 Jul 2011 22:13:29 +0200 Subject: PM / Domains: Wakeup devices support for system sleep transitions There is the problem how to handle devices set up to wake up the system from sleep states during system-wide power transitions. In some cases, those devices can be turned off entirely, because the wakeup signals will be generated on their behalf anyway. In some other cases, they will generate wakeup signals if their clocks are stopped, but only if power is not removed from them. Finally, in some cases, they can only generate wakeup signals if power is not removed from them and their clocks are enabled. To allow platform-specific code to decide whether or not to put wakeup devices (and their PM domains) into low-power state during system-wide transitions, such as system suspend, introduce a new generic PM domain callback, .active_wakeup(), that will be used during the "noirq" phase of system suspend and hibernation (after image creation) to decide what to do with wakeup devices. Specifically, if this callback is present and returns "true", the generic PM domain code will not execute .stop_device() for the given wakeup device and its PM domain won't be powered off. Signed-off-by: Rafael J. Wysocki Acked-by: Kevin Hilman --- drivers/base/power/domain.c | 8 ++++++++ include/linux/pm_domain.h | 1 + 2 files changed, 9 insertions(+) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 33086e9afaf6..1aed94c73cfc 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -450,6 +450,10 @@ static int pm_genpd_suspend_noirq(struct device *dev) if (ret) return ret; + if (device_may_wakeup(dev) + && genpd->active_wakeup && genpd->active_wakeup(dev)) + return 0; + if (genpd->stop_device) genpd->stop_device(dev); @@ -670,6 +674,10 @@ static int pm_genpd_dev_poweroff_noirq(struct device *dev) if (ret) return ret; + if (device_may_wakeup(dev) + && genpd->active_wakeup && genpd->active_wakeup(dev)) + return 0; + if (genpd->stop_device) genpd->stop_device(dev); diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 7961b0dac437..98491ee35102 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -38,6 +38,7 @@ struct generic_pm_domain { int (*power_on)(struct generic_pm_domain *domain); int (*start_device)(struct device *dev); int (*stop_device)(struct device *dev); + bool (*active_wakeup)(struct device *dev); }; static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd) -- cgit v1.2.2