diff options
author | Rafael J. Wysocki <rjw@sisk.pl> | 2011-07-15 23:59:09 +0200 |
---|---|---|
committer | Rafael J. Wysocki <rjw@sisk.pl> | 2011-07-15 23:59:09 +0200 |
commit | ba1389d74f34c0c6e95cc135a332cd29c29d9c20 (patch) | |
tree | 53813843d22cfcfe6d466a5daa44c646f8157980 /drivers/base | |
parent | f0c077a8b7f9dce590c760a7b2f3c417dffa52d1 (diff) | |
parent | 5ca80817e231723f1399bff495854ba2171103ca (diff) |
Merge branch 'pm-domains' into for-linus
* pm-domains: (33 commits)
ARM / shmobile: Return -EBUSY from A4LC power off if A3RV is active
PM / Domains: Take .power_off() error code into account
ARM / shmobile: Use genpd_queue_power_off_work()
ARM / shmobile: Use pm_genpd_poweroff_unused()
PM / Domains: Introduce function to power off all unused PM domains
PM / Domains: Queue up power off work only if it is not pending
PM / Domains: Improve handling of wakeup devices during system suspend
PM / Domains: Do not restore all devices on power off error
PM / Domains: Allow callbacks to execute all runtime PM helpers
PM / Domains: Do not execute device callbacks under locks
PM / Domains: Make failing pm_genpd_prepare() clean up properly
PM / Domains: Set device state to "active" during system resume
ARM: mach-shmobile: sh7372 A3RV requires A4LC
PM / Domains: Export pm_genpd_poweron() in header
ARM: mach-shmobile: sh7372 late pm domain off
ARM: mach-shmobile: Runtime PM late init callback
ARM: mach-shmobile: sh7372 D4 support
ARM: mach-shmobile: sh7372 A4MP support
ARM: mach-shmobile: sh7372: make sure that fsi is peripheral of spu2
ARM: mach-shmobile: sh7372 A3SG support
...
Diffstat (limited to 'drivers/base')
-rw-r--r-- | drivers/base/power/Makefile | 1 | ||||
-rw-r--r-- | drivers/base/power/clock_ops.c | 234 | ||||
-rw-r--r-- | drivers/base/power/domain.c | 1273 | ||||
-rw-r--r-- | drivers/base/power/generic_ops.c | 98 | ||||
-rw-r--r-- | drivers/base/power/main.c | 30 | ||||
-rw-r--r-- | drivers/base/power/runtime.c | 12 |
6 files changed, 1524 insertions, 124 deletions
diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile index 3647e114d0e..2639ae79a37 100644 --- a/drivers/base/power/Makefile +++ b/drivers/base/power/Makefile @@ -3,6 +3,7 @@ obj-$(CONFIG_PM_SLEEP) += main.o wakeup.o obj-$(CONFIG_PM_RUNTIME) += runtime.o obj-$(CONFIG_PM_TRACE_RTC) += trace.o obj-$(CONFIG_PM_OPP) += opp.o +obj-$(CONFIG_PM_GENERIC_DOMAINS) += domain.o obj-$(CONFIG_HAVE_CLK) += clock_ops.o ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG
\ No newline at end of file diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index ad367c4139b..a846b2f95cf 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -15,9 +15,9 @@ #include <linux/slab.h> #include <linux/err.h> -#ifdef CONFIG_PM_RUNTIME +#ifdef CONFIG_PM -struct pm_runtime_clk_data { +struct pm_clk_data { struct list_head clock_list; struct mutex lock; }; @@ -36,25 +36,25 @@ struct pm_clock_entry { enum pce_status status; }; -static struct pm_runtime_clk_data *__to_prd(struct device *dev) +static struct pm_clk_data *__to_pcd(struct device *dev) { return dev ? dev->power.subsys_data : NULL; } /** - * pm_runtime_clk_add - Start using a device clock for runtime PM. - * @dev: Device whose clock is going to be used for runtime PM. + * pm_clk_add - Start using a device clock for power management. + * @dev: Device whose clock is going to be used for power management. * @con_id: Connection ID of the clock. * * Add the clock represented by @con_id to the list of clocks used for - * the runtime PM of @dev. + * the power management of @dev. */ -int pm_runtime_clk_add(struct device *dev, const char *con_id) +int pm_clk_add(struct device *dev, const char *con_id) { - struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; - if (!prd) + if (!pcd) return -EINVAL; ce = kzalloc(sizeof(*ce), GFP_KERNEL); @@ -73,20 +73,20 @@ int pm_runtime_clk_add(struct device *dev, const char *con_id) } } - mutex_lock(&prd->lock); - list_add_tail(&ce->node, &prd->clock_list); - mutex_unlock(&prd->lock); + mutex_lock(&pcd->lock); + list_add_tail(&ce->node, &pcd->clock_list); + mutex_unlock(&pcd->lock); return 0; } /** - * __pm_runtime_clk_remove - Destroy runtime PM clock entry. - * @ce: Runtime PM clock entry to destroy. + * __pm_clk_remove - Destroy PM clock entry. + * @ce: PM clock entry to destroy. * - * This routine must be called under the mutex protecting the runtime PM list - * of clocks corresponding the the @ce's device. + * This routine must be called under the mutex protecting the PM list of clocks + * corresponding the the @ce's device. */ -static void __pm_runtime_clk_remove(struct pm_clock_entry *ce) +static void __pm_clk_remove(struct pm_clock_entry *ce) { if (!ce) return; @@ -108,95 +108,99 @@ static void __pm_runtime_clk_remove(struct pm_clock_entry *ce) } /** - * pm_runtime_clk_remove - Stop using a device clock for runtime PM. - * @dev: Device whose clock should not be used for runtime PM any more. + * pm_clk_remove - Stop using a device clock for power management. + * @dev: Device whose clock should not be used for PM any more. * @con_id: Connection ID of the clock. * * Remove the clock represented by @con_id from the list of clocks used for - * the runtime PM of @dev. + * the power management of @dev. */ -void pm_runtime_clk_remove(struct device *dev, const char *con_id) +void pm_clk_remove(struct device *dev, const char *con_id) { - struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; - if (!prd) + if (!pcd) return; - mutex_lock(&prd->lock); + mutex_lock(&pcd->lock); - list_for_each_entry(ce, &prd->clock_list, node) { + list_for_each_entry(ce, &pcd->clock_list, node) { if (!con_id && !ce->con_id) { - __pm_runtime_clk_remove(ce); + __pm_clk_remove(ce); break; } else if (!con_id || !ce->con_id) { continue; } else if (!strcmp(con_id, ce->con_id)) { - __pm_runtime_clk_remove(ce); + __pm_clk_remove(ce); break; } } - mutex_unlock(&prd->lock); + mutex_unlock(&pcd->lock); } /** - * pm_runtime_clk_init - Initialize a device's list of runtime PM clocks. - * @dev: Device to initialize the list of runtime PM clocks for. + * pm_clk_init - Initialize a device's list of power management clocks. + * @dev: Device to initialize the list of PM clocks for. * - * Allocate a struct pm_runtime_clk_data object, initialize its lock member and + * Allocate a struct pm_clk_data object, initialize its lock member and * make the @dev's power.subsys_data field point to it. */ -int pm_runtime_clk_init(struct device *dev) +int pm_clk_init(struct device *dev) { - struct pm_runtime_clk_data *prd; + struct pm_clk_data *pcd; - prd = kzalloc(sizeof(*prd), GFP_KERNEL); - if (!prd) { - dev_err(dev, "Not enough memory fo runtime PM data.\n"); + pcd = kzalloc(sizeof(*pcd), GFP_KERNEL); + if (!pcd) { + dev_err(dev, "Not enough memory for PM clock data.\n"); return -ENOMEM; } - INIT_LIST_HEAD(&prd->clock_list); - mutex_init(&prd->lock); - dev->power.subsys_data = prd; + INIT_LIST_HEAD(&pcd->clock_list); + mutex_init(&pcd->lock); + dev->power.subsys_data = pcd; return 0; } /** - * pm_runtime_clk_destroy - Destroy a device's list of runtime PM clocks. - * @dev: Device to destroy the list of runtime PM clocks for. + * pm_clk_destroy - Destroy a device's list of power management clocks. + * @dev: Device to destroy the list of PM clocks for. * * Clear the @dev's power.subsys_data field, remove the list of clock entries - * from the struct pm_runtime_clk_data object pointed to by it before and free + * from the struct pm_clk_data object pointed to by it before and free * that object. */ -void pm_runtime_clk_destroy(struct device *dev) +void pm_clk_destroy(struct device *dev) { - struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce, *c; - if (!prd) + if (!pcd) return; dev->power.subsys_data = NULL; - mutex_lock(&prd->lock); + mutex_lock(&pcd->lock); - list_for_each_entry_safe_reverse(ce, c, &prd->clock_list, node) - __pm_runtime_clk_remove(ce); + list_for_each_entry_safe_reverse(ce, c, &pcd->clock_list, node) + __pm_clk_remove(ce); - mutex_unlock(&prd->lock); + mutex_unlock(&pcd->lock); - kfree(prd); + kfree(pcd); } +#endif /* CONFIG_PM */ + +#ifdef CONFIG_PM_RUNTIME + /** - * pm_runtime_clk_acquire - Acquire a device clock. + * pm_clk_acquire - Acquire a device clock. * @dev: Device whose clock is to be acquired. * @con_id: Connection ID of the clock. */ -static void pm_runtime_clk_acquire(struct device *dev, +static void pm_clk_acquire(struct device *dev, struct pm_clock_entry *ce) { ce->clk = clk_get(dev, ce->con_id); @@ -209,24 +213,24 @@ static void pm_runtime_clk_acquire(struct device *dev, } /** - * pm_runtime_clk_suspend - Disable clocks in a device's runtime PM clock list. + * pm_clk_suspend - Disable clocks in a device's PM clock list. * @dev: Device to disable the clocks for. */ -int pm_runtime_clk_suspend(struct device *dev) +int pm_clk_suspend(struct device *dev) { - struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; dev_dbg(dev, "%s()\n", __func__); - if (!prd) + if (!pcd) return 0; - mutex_lock(&prd->lock); + mutex_lock(&pcd->lock); - list_for_each_entry_reverse(ce, &prd->clock_list, node) { + list_for_each_entry_reverse(ce, &pcd->clock_list, node) { if (ce->status == PCE_STATUS_NONE) - pm_runtime_clk_acquire(dev, ce); + pm_clk_acquire(dev, ce); if (ce->status < PCE_STATUS_ERROR) { clk_disable(ce->clk); @@ -234,30 +238,30 @@ int pm_runtime_clk_suspend(struct device *dev) } } - mutex_unlock(&prd->lock); + mutex_unlock(&pcd->lock); return 0; } /** - * pm_runtime_clk_resume - Enable clocks in a device's runtime PM clock list. + * pm_clk_resume - Enable clocks in a device's PM clock list. * @dev: Device to enable the clocks for. */ -int pm_runtime_clk_resume(struct device *dev) +int pm_clk_resume(struct device *dev) { - struct pm_runtime_clk_data *prd = __to_prd(dev); + struct pm_clk_data *pcd = __to_pcd(dev); struct pm_clock_entry *ce; dev_dbg(dev, "%s()\n", __func__); - if (!prd) + if (!pcd) return 0; - mutex_lock(&prd->lock); + mutex_lock(&pcd->lock); - list_for_each_entry(ce, &prd->clock_list, node) { + list_for_each_entry(ce, &pcd->clock_list, node) { if (ce->status == PCE_STATUS_NONE) - pm_runtime_clk_acquire(dev, ce); + pm_clk_acquire(dev, ce); if (ce->status < PCE_STATUS_ERROR) { clk_enable(ce->clk); @@ -265,28 +269,28 @@ int pm_runtime_clk_resume(struct device *dev) } } - mutex_unlock(&prd->lock); + mutex_unlock(&pcd->lock); return 0; } /** - * pm_runtime_clk_notify - Notify routine for device addition and removal. + * pm_clk_notify - Notify routine for device addition and removal. * @nb: Notifier block object this function is a member of. * @action: Operation being carried out by the caller. * @data: Device the routine is being run for. * * For this function to work, @nb must be a member of an object of type * struct pm_clk_notifier_block containing all of the requisite data. - * Specifically, the pwr_domain member of that object is copied to the device's - * pwr_domain field and its con_ids member is used to populate the device's list - * of runtime PM clocks, depending on @action. + * Specifically, the pm_domain member of that object is copied to the device's + * pm_domain field and its con_ids member is used to populate the device's list + * of PM clocks, depending on @action. * - * If the device's pwr_domain field is already populated with a value different + * If the device's pm_domain field is already populated with a value different * from the one stored in the struct pm_clk_notifier_block object, the function * does nothing. */ -static int pm_runtime_clk_notify(struct notifier_block *nb, +static int pm_clk_notify(struct notifier_block *nb, unsigned long action, void *data) { struct pm_clk_notifier_block *clknb; @@ -300,28 +304,28 @@ static int pm_runtime_clk_notify(struct notifier_block *nb, switch (action) { case BUS_NOTIFY_ADD_DEVICE: - if (dev->pwr_domain) + if (dev->pm_domain) break; - error = pm_runtime_clk_init(dev); + error = pm_clk_init(dev); if (error) break; - dev->pwr_domain = clknb->pwr_domain; + dev->pm_domain = clknb->pm_domain; if (clknb->con_ids[0]) { for (con_id = clknb->con_ids; *con_id; con_id++) - pm_runtime_clk_add(dev, *con_id); + pm_clk_add(dev, *con_id); } else { - pm_runtime_clk_add(dev, NULL); + pm_clk_add(dev, NULL); } break; case BUS_NOTIFY_DEL_DEVICE: - if (dev->pwr_domain != clknb->pwr_domain) + if (dev->pm_domain != clknb->pm_domain) break; - dev->pwr_domain = NULL; - pm_runtime_clk_destroy(dev); + dev->pm_domain = NULL; + pm_clk_destroy(dev); break; } @@ -330,6 +334,60 @@ static int pm_runtime_clk_notify(struct notifier_block *nb, #else /* !CONFIG_PM_RUNTIME */ +#ifdef CONFIG_PM + +/** + * pm_clk_suspend - Disable clocks in a device's PM clock list. + * @dev: Device to disable the clocks for. + */ +int pm_clk_suspend(struct device *dev) +{ + struct pm_clk_data *pcd = __to_pcd(dev); + struct pm_clock_entry *ce; + + dev_dbg(dev, "%s()\n", __func__); + + /* If there is no driver, the clocks are already disabled. */ + if (!pcd || !dev->driver) + return 0; + + mutex_lock(&pcd->lock); + + list_for_each_entry_reverse(ce, &pcd->clock_list, node) + clk_disable(ce->clk); + + mutex_unlock(&pcd->lock); + + return 0; +} + +/** + * pm_clk_resume - Enable clocks in a device's PM clock list. + * @dev: Device to enable the clocks for. + */ +int pm_clk_resume(struct device *dev) +{ + struct pm_clk_data *pcd = __to_pcd(dev); + struct pm_clock_entry *ce; + + dev_dbg(dev, "%s()\n", __func__); + + /* If there is no driver, the clocks should remain disabled. */ + if (!pcd || !dev->driver) + return 0; + + mutex_lock(&pcd->lock); + + list_for_each_entry(ce, &pcd->clock_list, node) + clk_enable(ce->clk); + + mutex_unlock(&pcd->lock); + + return 0; +} + +#endif /* CONFIG_PM */ + /** * enable_clock - Enable a device clock. * @dev: Device whose clock is to be enabled. @@ -365,7 +423,7 @@ static void disable_clock(struct device *dev, const char *con_id) } /** - * pm_runtime_clk_notify - Notify routine for device addition and removal. + * pm_clk_notify - Notify routine for device addition and removal. * @nb: Notifier block object this function is a member of. * @action: Operation being carried out by the caller. * @data: Device the routine is being run for. @@ -375,7 +433,7 @@ static void disable_clock(struct device *dev, const char *con_id) * Specifically, the con_ids member of that object is used to enable or disable * the device's clocks, depending on @action. */ -static int pm_runtime_clk_notify(struct notifier_block *nb, +static int pm_clk_notify(struct notifier_block *nb, unsigned long action, void *data) { struct pm_clk_notifier_block *clknb; @@ -411,21 +469,21 @@ static int pm_runtime_clk_notify(struct notifier_block *nb, #endif /* !CONFIG_PM_RUNTIME */ /** - * pm_runtime_clk_add_notifier - Add bus type notifier for runtime PM clocks. + * pm_clk_add_notifier - Add bus type notifier for power management clocks. * @bus: Bus type to add the notifier to. * @clknb: Notifier to be added to the given bus type. * * The nb member of @clknb is not expected to be initialized and its - * notifier_call member will be replaced with pm_runtime_clk_notify(). However, + * notifier_call member will be replaced with pm_clk_notify(). However, * the remaining members of @clknb should be populated prior to calling this * routine. */ -void pm_runtime_clk_add_notifier(struct bus_type *bus, +void pm_clk_add_notifier(struct bus_type *bus, struct pm_clk_notifier_block *clknb) { if (!bus || !clknb) return; - clknb->nb.notifier_call = pm_runtime_clk_notify; + clknb->nb.notifier_call = pm_clk_notify; bus_register_notifier(bus, &clknb->nb); } diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c new file mode 100644 index 00000000000..be8714aa9dd --- /dev/null +++ b/drivers/base/power/domain.c @@ -0,0 +1,1273 @@ +/* + * drivers/base/power/domain.c - Common code related to device power domains. + * + * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp. + * + * This file is released under the GPLv2. + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/pm_runtime.h> +#include <linux/pm_domain.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/sched.h> +#include <linux/suspend.h> + +static LIST_HEAD(gpd_list); +static DEFINE_MUTEX(gpd_list_lock); + +#ifdef CONFIG_PM + +static struct generic_pm_domain *dev_to_genpd(struct device *dev) +{ + if (IS_ERR_OR_NULL(dev->pm_domain)) + return ERR_PTR(-EINVAL); + + return pd_to_genpd(dev->pm_domain); +} + +static void genpd_sd_counter_dec(struct generic_pm_domain *genpd) +{ + if (!WARN_ON(genpd->sd_count == 0)) + genpd->sd_count--; +} + +static void genpd_acquire_lock(struct generic_pm_domain *genpd) +{ + DEFINE_WAIT(wait); + + mutex_lock(&genpd->lock); + /* + * Wait for the domain to transition into either the active, + * or the power off state. + */ + for (;;) { + prepare_to_wait(&genpd->status_wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + if (genpd->status == GPD_STATE_ACTIVE + || genpd->status == GPD_STATE_POWER_OFF) + break; + mutex_unlock(&genpd->lock); + + schedule(); + + mutex_lock(&genpd->lock); + } + finish_wait(&genpd->status_wait_queue, &wait); +} + +static void genpd_release_lock(struct generic_pm_domain *genpd) +{ + mutex_unlock(&genpd->lock); +} + +static void genpd_set_active(struct generic_pm_domain *genpd) +{ + if (genpd->resume_count == 0) + genpd->status = GPD_STATE_ACTIVE; +} + +/** + * pm_genpd_poweron - Restore power to a given PM domain and its parents. + * @genpd: PM domain to power up. + * + * Restore power to @genpd and all of its parents so that it is possible to + * resume a device belonging to it. + */ +int pm_genpd_poweron(struct generic_pm_domain *genpd) +{ + struct generic_pm_domain *parent = genpd->parent; + DEFINE_WAIT(wait); + int ret = 0; + + start: + if (parent) { + genpd_acquire_lock(parent); + mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING); + } else { + mutex_lock(&genpd->lock); + } + + if (genpd->status == GPD_STATE_ACTIVE + || (genpd->prepared_count > 0 && genpd->suspend_power_off)) + goto out; + + if (genpd->status != GPD_STATE_POWER_OFF) { + genpd_set_active(genpd); + goto out; + } + + if (parent && parent->status != GPD_STATE_ACTIVE) { + mutex_unlock(&genpd->lock); + genpd_release_lock(parent); + + ret = pm_genpd_poweron(parent); + if (ret) + return ret; + + goto start; + } + + if (genpd->power_on) { + int ret = genpd->power_on(genpd); + if (ret) + goto out; + } + + genpd_set_active(genpd); + if (parent) + parent->sd_count++; + + out: + mutex_unlock(&genpd->lock); + if (parent) + genpd_release_lock(parent); + + return ret; +} + +#endif /* CONFIG_PM */ + +#ifdef CONFIG_PM_RUNTIME + +/** + * __pm_genpd_save_device - Save the pre-suspend state of a device. + * @dle: Device list entry of the device to save the state of. + * @genpd: PM domain the device belongs to. + */ +static int __pm_genpd_save_device(struct dev_list_entry *dle, + struct generic_pm_domain *genpd) + __releases(&genpd->lock) __acquires(&genpd->lock) +{ + struct device *dev = dle->dev; + struct device_driver *drv = dev->driver; + int ret = 0; + + if (dle->need_restore) + return 0; + + mutex_unlock(&genpd->lock); + + if (drv && drv->pm && drv->pm->runtime_suspend) { + if (genpd->start_device) + genpd->start_device(dev); + + ret = drv->pm->runtime_suspend(dev); + + if (genpd->stop_device) + genpd->stop_device(dev); + } + + mutex_lock(&genpd->lock); + + if (!ret) + dle->need_restore = true; + + return ret; +} + +/** + * __pm_genpd_restore_device - Restore the pre-suspend state of a device. + * @dle: Device list entry of the device to restore the state of. + * @genpd: PM domain the device belongs to. + */ +static void __pm_genpd_restore_device(struct dev_list_entry *dle, + struct generic_pm_domain *genpd) + __releases(&genpd->lock) __acquires(&genpd->lock) +{ + struct device *dev = dle->dev; + struct device_driver *drv = dev->driver; + + if (!dle->need_restore) + return; + + mutex_unlock(&genpd->lock); + + if (drv && drv->pm && drv->pm->runtime_resume) { + if (genpd->start_device) + genpd->start_device(dev); + + drv->pm->runtime_resume(dev); + + if (genpd->stop_device) + genpd->stop_device(dev); + } + + mutex_lock(&genpd->lock); + + dle->need_restore = false; +} + +/** + * genpd_abort_poweroff - Check if a PM domain power off should be aborted. + * @genpd: PM domain to check. + * + * Return true if a PM domain's status changed to GPD_STATE_ACTIVE during + * a "power off" operation, which means that a "power on" has occured in the + * meantime, or if its resume_count field is different from zero, which means + * that one of its devices has been resumed in the meantime. + */ +static bool genpd_abort_poweroff(struct generic_pm_domain *genpd) +{ + return genpd->status == GPD_STATE_ACTIVE || genpd->resume_count > 0; +} + +/** + * genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff(). + * @genpd: PM domait to power off. + * + * Queue up the execution of pm_genpd_poweroff() unless it's already been done + * before. + */ +void genpd_queue_power_off_work(struct generic_pm_domain *genpd) +{ + if (!work_pending(&genpd->power_off_work)) + queue_work(pm_wq, &genpd->power_off_work); +} + +/** + * pm_genpd_poweroff - Remove power from a given PM domain. + * @genpd: PM 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_pm_domain *genpd) + __releases(&genpd->lock) __acquires(&genpd->lock) +{ + struct generic_pm_domain *parent; + struct dev_list_entry *dle; + unsigned int not_suspended; + int ret = 0; + + start: + /* + * Do not try to power off the domain in the following situations: + * (1) The domain is already in the "power off" state. + * (2) System suspend is in progress. + * (3) One of the domain's devices is being resumed right now. + */ + if (genpd->status == GPD_STATE_POWER_OFF || genpd->prepared_count > 0 + || genpd->resume_count > 0) + return 0; + + if (genpd->sd_count > 0) + return -EBUSY; + + not_suspended = 0; + list_for_each_entry(dle, &genpd->dev_list, node) + if (dle->dev->driver && !pm_runtime_suspended(dle->dev)) + not_suspended++; + + if (not_suspended > genpd->in_progress) + return -EBUSY; + + if (genpd->poweroff_task) { + /* + * Another instance of pm_genpd_poweroff() is executing + * callbacks, so tell it to start over and return. + */ + genpd->status = GPD_STATE_REPEAT; + return 0; + } + + if (genpd->gov && genpd->gov->power_down_ok) { + if (!genpd->gov->power_down_ok(&genpd->domain)) + return -EAGAIN; + } + + genpd->status = GPD_STATE_BUSY; + genpd->poweroff_task = current; + + list_for_each_entry_reverse(dle, &genpd->dev_list, node) { + ret = __pm_genpd_save_device(dle, genpd); + if (ret) { + genpd_set_active(genpd); + goto out; + } + + if (genpd_abort_poweroff(genpd)) + goto out; + + if (genpd->status == GPD_STATE_REPEAT) { + genpd->poweroff_task = NULL; + goto start; + } + } + + parent = genpd->parent; + if (parent) { + mutex_unlock(&genpd->lock); + + genpd_acquire_lock(parent); + mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING); + + if (genpd_abort_poweroff(genpd)) { + genpd_release_lock(parent); + goto out; + } + } + + if (genpd->power_off) { + ret = genpd->power_off(genpd); + if (ret == -EBUSY) { + genpd_set_active(genpd); + if (parent) + genpd_release_lock(parent); + + goto out; + } + } + + genpd->status = GPD_STATE_POWER_OFF; + + if (parent) { + genpd_sd_counter_dec(parent); + if (parent->sd_count == 0) + genpd_queue_power_off_work(parent); + + genpd_release_lock(parent); + } + + out: + genpd->poweroff_task = NULL; + wake_up_all(&genpd->status_wait_queue); + return ret; +} + +/** + * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0. + * @work: Work structure used for scheduling the execution of this function. + */ +static void genpd_power_off_work_fn(struct work_struct *work) +{ + struct generic_pm_domain *genpd; + + genpd = container_of(work, struct generic_pm_domain, power_off_work); + + genpd_acquire_lock(genpd); + pm_genpd_poweroff(genpd); + genpd_release_lock(genpd); +} + +/** + * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain. + * @dev: Device to suspend. + * + * Carry out a runtime suspend of a device under the assumption that its + * pm_domain field points to the domain member of an object of type + * struct generic_pm_domain representing a PM domain consisting of I/O devices. + */ +static int pm_genpd_runtime_suspend(struct device *dev) +{ + struct generic_pm_domain *genpd; + + dev_dbg(dev, "%s()\n", __func__); + + genpd = dev_to_genpd(dev); + if (IS_ERR(genpd)) + return -EINVAL; + + if (genpd->stop_device) { + int ret = genpd->stop_device(dev); + if (ret) + return ret; + } + + mutex_lock(&genpd->lock); + genpd->in_progress++; + pm_genpd_poweroff(genpd); + genpd->in_progress--; + mutex_unlock(&genpd->lock); + + return 0; +} + +/** + * __pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain. + * @dev: Device to resume. + * @genpd: PM domain the device belongs to. + */ +static void __pm_genpd_runtime_resume(struct device *dev, + struct generic_pm_domain *genpd) +{ + struct dev_list_entry *dle; + + list_for_each_entry(dle, &genpd->dev_list, node) { + if (dle->dev == dev) { + __pm_genpd_restore_device(dle, genpd); + break; + } + } +} + +/** + * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain. + * @dev: Device to resume. + * + * Carry out a runtime resume of a device under the assumption that its + * pm_domain field points to the domain member of an object of type + * struct generic_pm_domain representing a PM domain consisting of I/O devices. + */ +static int pm_genpd_runtime_resume(struct device *dev) +{ + struct generic_pm_domain *genpd; + DEFINE_WAIT(wait); + int ret; + + dev_dbg(dev, "%s()\n", __func__); + + genpd = dev_to_genpd(dev); + if (IS_ERR(genpd)) + return -EINVAL; + + ret = pm_genpd_poweron(genpd); + if (ret) + return ret; + + mutex_lock(&genpd->lock); + genpd->status = GPD_STATE_BUSY; + genpd->resume_count++; + for (;;) { + prepare_to_wait(&genpd->status_wait_queue, &wait, + TASK_UNINTERRUPTIBLE); + /* + * If current is the powering off task, we have been called + * reentrantly from one of the device callbacks, so we should + * not wait. + */ + if (!genpd->poweroff_task || genpd->poweroff_task == current) + break; + mutex_unlock(&genpd->lock); + + schedule(); + + mutex_lock(&genpd->lock); + } + finish_wait(&genpd->status_wait_queue, &wait); + __pm_genpd_runtime_resume(dev, genpd); + genpd->resume_count--; + genpd_set_active(genpd); + wake_up_all(&genpd->status_wait_queue); + mutex_unlock(&genpd->lock); + + if (genpd->start_device) + genpd->start_device(dev); + + return 0; +} + +#else + +static inline void genpd_power_off_work_fn(struct work_struct *work) {} +static inline void __pm_genpd_runtime_resume(struct device *dev, + struct generic_pm_domain *genpd) {} + +#define pm_genpd_runtime_suspend NULL +#define pm_genpd_runtime_resume NULL + +#endif /* CONFIG_PM_RUNTIME */ + +#ifdef CONFIG_PM_SLEEP + +/** + * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its parents. + * @genpd: PM domain to power off, if possible. + * + * 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 parent. + * + * 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). + */ +static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd) +{ + struct generic_pm_domain *parent = genpd->parent; + + if (genpd->status == GPD_STATE_POWER_OFF) + return; + + if (genpd->suspended_count != genpd->device_count || genpd->sd_count > 0) + return; + + if (genpd->power_off) + genpd->power_off(genpd); + + genpd->status = GPD_STATE_POWER_OFF; + if (parent) { + genpd_sd_counter_dec(parent); + pm_genpd_sync_poweroff(parent); + } +} + +/** + * resume_needed - Check whether to resume a device before system suspend. + * @dev: Device to check. + * @genpd: PM domain the device belongs to. + * + * There are two cases in which a device that can wake up the system from sleep + * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled + * to wake up the system and it has to remain active for this purpose while the + * system is in the sleep state and (2) if the device is not enabled to wake up + * the system from sleep states and it generally doesn't generate wakeup signals + * by itself (those signals are generated on its behalf by other parts of the + * system). In the latter case it may be necessary to reconfigure the device's + * wakeup settings during system suspend, because it may have been set up to + * signal remote wakeup from the system's working state as needed by runtime PM. + * Return 'true' in either of the above cases. + */ +static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd) +{ + bool active_wakeup; + + if (!device_can_wakeup(dev)) + return false; + + active_wakeup = genpd->active_wakeup && genpd->active_wakeup(dev); + return device_may_wakeup(dev) ? active_wakeup : !active_wakeup; +} + +/** + * pm_genpd_prepare - Start power transition of a device in a PM domain. + * @dev: Device to start the transition of. + * + * Start a power transition of a device (during a system-wide power transition) + * under the assumption that its pm_domain field points to the domain member of + * an object of type struct generic_pm_domain representing a PM domain + * consisting of I/O devices. + */ +static int pm_genpd_prepare(struct device *dev) +{ + struct generic_pm_domain *genpd; + int ret; + + dev_dbg(dev, "%s()\n", __func__); + + genpd = dev_to_genpd(dev); + if (IS_ERR(genpd)) + return -EINVAL; + + /* + * If a wakeup request is pending for the device, it should be woken up + * at this point and a system wakeup event should be reported if it's + * set up to wake up the system from sleep states. + */ + pm_runtime_get_noresume(dev); + if (pm_runtime_barrier(dev) && device_may_wakeup(dev)) + pm_wakeup_event(dev, 0); + + if (pm_wakeup_pending()) { + pm_runtime_put_sync(dev); + return -EBUSY; + } + + if (resume_needed(dev, genpd)) + pm_runtime_resume(dev); + + genpd_acquire_lock(genpd); + + if (genpd->prepared_count++ == 0) + genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF; + + genpd_release_lock(genpd); + + if (genpd->suspend_power_off) { + pm_runtime_put_noidle(dev); + return 0; + } + + /* + * The PM domain must be in the GPD_STATE_ACTIVE state at this point, + * so pm_genpd_poweron() will return immediately, but if the device + * is suspended (e.g. it's been stopped by .stop_device()), we need + * to make it operational. + */ + pm_runtime_resume(dev); + __pm_runtime_disable(dev, false); + + ret = pm_generic_prepare(dev); + if (ret) { + mutex_lock(&genpd->lock); + + if (--g |