From 77f827de07432a74821cf0f831d699544b2d474f Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 6 Aug 2012 01:39:57 +0200 Subject: [PATCH] PM / Domains: Add power off/on function for system core suspend stage Introduce function pm_genpd_syscore_switch() and two wrappers around it, pm_genpd_syscore_poweroff() and pm_genpd_syscore_poweron(), allowing the callers to let the generic PM domains framework know that the given device is not necessary any more and its PM domain can be turned off (the former) or that the given device will be required immediately, so its PM domain has to be turned on (the latter) during the system core (syscore) stage of system suspend (or hibernation) and resume. These functions will be used for handling devices registered as clock sources and clock event devices that belong to PM domains. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/domain.c | 57 +++++++++++++++++++++++++++++++++---- include/linux/pm_domain.h | 16 +++++++++++ kernel/power/Kconfig | 4 +++ 3 files changed, 71 insertions(+), 6 deletions(-) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 55c39f5b7a59..515c8ecf01ce 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -697,6 +697,24 @@ static inline void genpd_power_off_work_fn(struct work_struct *work) {} #ifdef CONFIG_PM_SLEEP +/** + * pm_genpd_present - Check if the given PM domain has been initialized. + * @genpd: PM domain to check. + */ +static bool pm_genpd_present(struct generic_pm_domain *genpd) +{ + struct generic_pm_domain *gpd; + + if (IS_ERR_OR_NULL(genpd)) + return false; + + list_for_each_entry(gpd, &gpd_list, gpd_list_node) + if (gpd == genpd) + return true; + + return false; +} + static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd, struct device *dev) { @@ -750,9 +768,10 @@ static int genpd_thaw_dev(struct generic_pm_domain *genpd, struct device *dev) * Check if the given PM domain can be powered off (during system suspend or * hibernation) and do that if so. Also, in that case propagate to its masters. * - * This function is only called in "noirq" stages of system power transitions, - * so it need not acquire locks (all of the "noirq" callbacks are executed - * sequentially, so it is guaranteed that it will never run twice in parallel). + * This function is only called in "noirq" and "syscore" stages of system power + * transitions, so it need not acquire locks (all of the "noirq" callbacks are + * executed sequentially, so it is guaranteed that it will never run twice in + * parallel). */ static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd) { @@ -780,9 +799,10 @@ static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd) * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters. * @genpd: PM domain to power on. * - * This function is only called in "noirq" stage of system power transitions, so - * it need not acquire locks (all of the "noirq" callbacks are executed - * sequentially, so it is guaranteed that it will never run twice in parallel). + * This function is only called in "noirq" and "syscore" stages of system power + * transitions, so it need not acquire locks (all of the "noirq" callbacks are + * executed sequentially, so it is guaranteed that it will never run twice in + * parallel). */ static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd) { @@ -1272,6 +1292,31 @@ static void pm_genpd_complete(struct device *dev) } } +/** + * pm_genpd_syscore_switch - Switch power during system core suspend or resume. + * @dev: Device that normally is marked as "always on" to switch power for. + * + * This routine may only be called during the system core (syscore) suspend or + * resume phase for devices whose "always on" flags are set. + */ +void pm_genpd_syscore_switch(struct device *dev, bool suspend) +{ + struct generic_pm_domain *genpd; + + genpd = dev_to_genpd(dev); + if (!pm_genpd_present(genpd)) + return; + + if (suspend) { + genpd->suspended_count++; + pm_genpd_sync_poweroff(genpd); + } else { + pm_genpd_sync_poweron(genpd); + genpd->suspended_count--; + } +} +EXPORT_SYMBOL_GPL(pm_genpd_syscore_switch); + #else #define pm_genpd_prepare NULL diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index a7d6172922d4..ab83cf3dfaac 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -258,4 +258,20 @@ static inline void genpd_queue_power_off_work(struct generic_pm_domain *gpd) {} static inline void pm_genpd_poweroff_unused(void) {} #endif +#ifdef CONFIG_PM_GENERIC_DOMAINS_SLEEP +extern void pm_genpd_syscore_switch(struct device *dev, bool suspend); +#else +static inline void pm_genpd_syscore_switch(struct device *dev, bool suspend) {} +#endif + +static inline void pm_genpd_syscore_poweroff(struct device *dev) +{ + pm_genpd_syscore_switch(dev, true); +} + +static inline void pm_genpd_syscore_poweron(struct device *dev) +{ + pm_genpd_syscore_switch(dev, false); +} + #endif /* _LINUX_PM_DOMAIN_H */ diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index a70518c9d82f..5dfdc9ea180b 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -263,6 +263,10 @@ config PM_GENERIC_DOMAINS bool depends on PM +config PM_GENERIC_DOMAINS_SLEEP + def_bool y + depends on PM_SLEEP && PM_GENERIC_DOMAINS + config PM_GENERIC_DOMAINS_RUNTIME def_bool y depends on PM_RUNTIME && PM_GENERIC_DOMAINS