From cf579dfb82550e34de7ccf3ef090d8b834ccd3a9 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 29 Jan 2012 20:38:29 +0100 Subject: PM / Sleep: Introduce "late suspend" and "early resume" of devices The current device suspend/resume phases during system-wide power transitions appear to be insufficient for some platforms that want to use the same callback routines for saving device states and related operations during runtime suspend/resume as well as during system suspend/resume. In principle, they could point their .suspend_noirq() and .resume_noirq() to the same callback routines as their .runtime_suspend() and .runtime_resume(), respectively, but at least some of them require device interrupts to be enabled while the code in those routines is running. It also makes sense to have device suspend-resume callbacks that will be executed with runtime PM disabled and with device interrupts enabled in case someone needs to run some special code in that context during system-wide power transitions. Apart from this, .suspend_noirq() and .resume_noirq() were introduced as a workaround for drivers using shared interrupts and failing to prevent their interrupt handlers from accessing suspended hardware. It appears to be better not to use them for other porposes, or we may have to deal with some serious confusion (which seems to be happening already). For the above reasons, introduce new device suspend/resume phases, "late suspend" and "early resume" (and analogously for hibernation) whose callback will be executed with runtime PM disabled and with device interrupts enabled and whose callback pointers generally may point to runtime suspend/resume routines. Signed-off-by: Rafael J. Wysocki Reviewed-by: Mark Brown Reviewed-by: Kevin Hilman --- drivers/base/power/main.c | 247 +++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 225 insertions(+), 22 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index e2cc3d2e0ecc..b462c0e341cb 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -47,6 +47,7 @@ typedef int (*pm_callback_t)(struct device *); LIST_HEAD(dpm_list); LIST_HEAD(dpm_prepared_list); LIST_HEAD(dpm_suspended_list); +LIST_HEAD(dpm_late_early_list); LIST_HEAD(dpm_noirq_list); struct suspend_stats suspend_stats; @@ -245,6 +246,40 @@ static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state) return NULL; } +/** + * pm_late_early_op - Return the PM operation appropriate for given PM event. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + * + * Runtime PM is disabled for @dev while this function is being executed. + */ +static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops, + pm_message_t state) +{ + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + return ops->suspend_late; + case PM_EVENT_RESUME: + return ops->resume_early; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATE_CALLBACKS + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + return ops->freeze_late; + case PM_EVENT_HIBERNATE: + return ops->poweroff_late; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + return ops->thaw_early; + case PM_EVENT_RESTORE: + return ops->restore_early; +#endif /* CONFIG_HIBERNATE_CALLBACKS */ + } + + return NULL; +} + /** * pm_noirq_op - Return the PM operation appropriate for given PM event. * @ops: PM operations to choose from. @@ -374,21 +409,21 @@ static int device_resume_noirq(struct device *dev, pm_message_t state) TRACE_RESUME(0); if (dev->pm_domain) { - info = "EARLY power domain "; + info = "noirq power domain "; callback = pm_noirq_op(&dev->pm_domain->ops, state); } else if (dev->type && dev->type->pm) { - info = "EARLY type "; + info = "noirq type "; callback = pm_noirq_op(dev->type->pm, state); } else if (dev->class && dev->class->pm) { - info = "EARLY class "; + info = "noirq class "; callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - info = "EARLY bus "; + info = "noirq bus "; callback = pm_noirq_op(dev->bus->pm, state); } if (!callback && dev->driver && dev->driver->pm) { - info = "EARLY driver "; + info = "noirq driver "; callback = pm_noirq_op(dev->driver->pm, state); } @@ -399,13 +434,13 @@ static int device_resume_noirq(struct device *dev, pm_message_t state) } /** - * dpm_resume_noirq - Execute "early resume" callbacks for non-sysdev devices. + * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices. * @state: PM transition of the system being carried out. * - * Call the "noirq" resume handlers for all devices marked as DPM_OFF_IRQ and + * Call the "noirq" resume handlers for all devices in dpm_noirq_list and * enable device drivers to receive interrupts. */ -void dpm_resume_noirq(pm_message_t state) +static void dpm_resume_noirq(pm_message_t state) { ktime_t starttime = ktime_get(); @@ -415,7 +450,7 @@ void dpm_resume_noirq(pm_message_t state) int error; get_device(dev); - list_move_tail(&dev->power.entry, &dpm_suspended_list); + list_move_tail(&dev->power.entry, &dpm_late_early_list); mutex_unlock(&dpm_list_mtx); error = device_resume_noirq(dev, state); @@ -423,6 +458,80 @@ void dpm_resume_noirq(pm_message_t state) suspend_stats.failed_resume_noirq++; dpm_save_failed_step(SUSPEND_RESUME_NOIRQ); dpm_save_failed_dev(dev_name(dev)); + pm_dev_err(dev, state, " noirq", error); + } + + mutex_lock(&dpm_list_mtx); + put_device(dev); + } + mutex_unlock(&dpm_list_mtx); + dpm_show_time(starttime, state, "noirq"); + resume_device_irqs(); +} + +/** + * device_resume_early - Execute an "early resume" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * + * Runtime PM is disabled for @dev while this function is being executed. + */ +static int device_resume_early(struct device *dev, pm_message_t state) +{ + pm_callback_t callback = NULL; + char *info = NULL; + int error = 0; + + TRACE_DEVICE(dev); + TRACE_RESUME(0); + + if (dev->pm_domain) { + info = "early power domain "; + callback = pm_late_early_op(&dev->pm_domain->ops, state); + } else if (dev->type && dev->type->pm) { + info = "early type "; + callback = pm_late_early_op(dev->type->pm, state); + } else if (dev->class && dev->class->pm) { + info = "early class "; + callback = pm_late_early_op(dev->class->pm, state); + } else if (dev->bus && dev->bus->pm) { + info = "early bus "; + callback = pm_late_early_op(dev->bus->pm, state); + } + + if (!callback && dev->driver && dev->driver->pm) { + info = "early driver "; + callback = pm_late_early_op(dev->driver->pm, state); + } + + error = dpm_run_callback(callback, dev, state, info); + + TRACE_RESUME(error); + return error; +} + +/** + * dpm_resume_early - Execute "early resume" callbacks for all devices. + * @state: PM transition of the system being carried out. + */ +static void dpm_resume_early(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_late_early_list)) { + struct device *dev = to_device(dpm_late_early_list.next); + int error; + + get_device(dev); + list_move_tail(&dev->power.entry, &dpm_suspended_list); + mutex_unlock(&dpm_list_mtx); + + error = device_resume_early(dev, state); + if (error) { + suspend_stats.failed_resume_early++; + dpm_save_failed_step(SUSPEND_RESUME_EARLY); + dpm_save_failed_dev(dev_name(dev)); pm_dev_err(dev, state, " early", error); } @@ -431,9 +540,18 @@ void dpm_resume_noirq(pm_message_t state) } mutex_unlock(&dpm_list_mtx); dpm_show_time(starttime, state, "early"); - resume_device_irqs(); } -EXPORT_SYMBOL_GPL(dpm_resume_noirq); + +/** + * dpm_resume_start - Execute "noirq" and "early" device callbacks. + * @state: PM transition of the system being carried out. + */ +void dpm_resume_start(pm_message_t state) +{ + dpm_resume_noirq(state); + dpm_resume_early(state); +} +EXPORT_SYMBOL_GPL(dpm_resume_start); /** * device_resume - Execute "resume" callbacks for given device. @@ -716,21 +834,21 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state) char *info = NULL; if (dev->pm_domain) { - info = "LATE power domain "; + info = "noirq power domain "; callback = pm_noirq_op(&dev->pm_domain->ops, state); } else if (dev->type && dev->type->pm) { - info = "LATE type "; + info = "noirq type "; callback = pm_noirq_op(dev->type->pm, state); } else if (dev->class && dev->class->pm) { - info = "LATE class "; + info = "noirq class "; callback = pm_noirq_op(dev->class->pm, state); } else if (dev->bus && dev->bus->pm) { - info = "LATE bus "; + info = "noirq bus "; callback = pm_noirq_op(dev->bus->pm, state); } if (!callback && dev->driver && dev->driver->pm) { - info = "LATE driver "; + info = "noirq driver "; callback = pm_noirq_op(dev->driver->pm, state); } @@ -738,21 +856,21 @@ static int device_suspend_noirq(struct device *dev, pm_message_t state) } /** - * dpm_suspend_noirq - Execute "late suspend" callbacks for non-sysdev devices. + * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices. * @state: PM transition of the system being carried out. * * Prevent device drivers from receiving interrupts and call the "noirq" suspend * handlers for all non-sysdev devices. */ -int dpm_suspend_noirq(pm_message_t state) +static int dpm_suspend_noirq(pm_message_t state) { ktime_t starttime = ktime_get(); int error = 0; suspend_device_irqs(); mutex_lock(&dpm_list_mtx); - while (!list_empty(&dpm_suspended_list)) { - struct device *dev = to_device(dpm_suspended_list.prev); + while (!list_empty(&dpm_late_early_list)) { + struct device *dev = to_device(dpm_late_early_list.prev); get_device(dev); mutex_unlock(&dpm_list_mtx); @@ -761,7 +879,7 @@ int dpm_suspend_noirq(pm_message_t state) mutex_lock(&dpm_list_mtx); if (error) { - pm_dev_err(dev, state, " late", error); + pm_dev_err(dev, state, " noirq", error); suspend_stats.failed_suspend_noirq++; dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ); dpm_save_failed_dev(dev_name(dev)); @@ -775,11 +893,96 @@ int dpm_suspend_noirq(pm_message_t state) mutex_unlock(&dpm_list_mtx); if (error) dpm_resume_noirq(resume_event(state)); + else + dpm_show_time(starttime, state, "noirq"); + return error; +} + +/** + * device_suspend_late - Execute a "late suspend" callback for given device. + * @dev: Device to handle. + * @state: PM transition of the system being carried out. + * + * Runtime PM is disabled for @dev while this function is being executed. + */ +static int device_suspend_late(struct device *dev, pm_message_t state) +{ + pm_callback_t callback = NULL; + char *info = NULL; + + if (dev->pm_domain) { + info = "late power domain "; + callback = pm_late_early_op(&dev->pm_domain->ops, state); + } else if (dev->type && dev->type->pm) { + info = "late type "; + callback = pm_late_early_op(dev->type->pm, state); + } else if (dev->class && dev->class->pm) { + info = "late class "; + callback = pm_late_early_op(dev->class->pm, state); + } else if (dev->bus && dev->bus->pm) { + info = "late bus "; + callback = pm_late_early_op(dev->bus->pm, state); + } + + if (!callback && dev->driver && dev->driver->pm) { + info = "late driver "; + callback = pm_late_early_op(dev->driver->pm, state); + } + + return dpm_run_callback(callback, dev, state, info); +} + +/** + * dpm_suspend_late - Execute "late suspend" callbacks for all devices. + * @state: PM transition of the system being carried out. + */ +static int dpm_suspend_late(pm_message_t state) +{ + ktime_t starttime = ktime_get(); + int error = 0; + + mutex_lock(&dpm_list_mtx); + while (!list_empty(&dpm_suspended_list)) { + struct device *dev = to_device(dpm_suspended_list.prev); + + get_device(dev); + mutex_unlock(&dpm_list_mtx); + + error = device_suspend_late(dev, state); + + mutex_lock(&dpm_list_mtx); + if (error) { + pm_dev_err(dev, state, " late", error); + suspend_stats.failed_suspend_late++; + dpm_save_failed_step(SUSPEND_SUSPEND_LATE); + dpm_save_failed_dev(dev_name(dev)); + put_device(dev); + break; + } + if (!list_empty(&dev->power.entry)) + list_move(&dev->power.entry, &dpm_late_early_list); + put_device(dev); + } + mutex_unlock(&dpm_list_mtx); + if (error) + dpm_resume_early(resume_event(state)); else dpm_show_time(starttime, state, "late"); + return error; } -EXPORT_SYMBOL_GPL(dpm_suspend_noirq); + +/** + * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks. + * @state: PM transition of the system being carried out. + */ +int dpm_suspend_end(pm_message_t state) +{ + int error = dpm_suspend_late(state); + + return error ? : dpm_suspend_noirq(state); +} +EXPORT_SYMBOL_GPL(dpm_suspend_end); /** * legacy_suspend - Execute a legacy (bus or class) suspend callback for device. -- cgit v1.2.3 From e470d06655e00749f6f9372e4fa4f20cea7ed7c5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 29 Jan 2012 20:38:41 +0100 Subject: PM / Sleep: Introduce generic callbacks for new device PM phases Introduce generic subsystem callbacks for the new phases of device suspend/resume during system power transitions: "late suspend", "early resume", "late freeze", "early thaw", "late poweroff", "early restore". Signed-off-by: Rafael J. Wysocki --- drivers/base/power/generic_ops.c | 157 ++++++++++++++++++++++++++------------- include/linux/pm.h | 6 ++ 2 files changed, 110 insertions(+), 53 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c index 10bdd793f0bd..d03d290f31c2 100644 --- a/drivers/base/power/generic_ops.c +++ b/drivers/base/power/generic_ops.c @@ -92,59 +92,28 @@ int pm_generic_prepare(struct device *dev) } /** - * __pm_generic_call - Generic suspend/freeze/poweroff/thaw subsystem callback. - * @dev: Device to handle. - * @event: PM transition of the system under way. - * @bool: Whether or not this is the "noirq" stage. - * - * Execute the PM callback corresponding to @event provided by the driver of - * @dev, if defined, and return its error code. Return 0 if the callback is - * not present. + * pm_generic_suspend_noirq - Generic suspend_noirq callback for subsystems. + * @dev: Device to suspend. */ -static int __pm_generic_call(struct device *dev, int event, bool noirq) +int pm_generic_suspend_noirq(struct device *dev) { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; - int (*callback)(struct device *); - - if (!pm) - return 0; - - switch (event) { - case PM_EVENT_SUSPEND: - callback = noirq ? pm->suspend_noirq : pm->suspend; - break; - case PM_EVENT_FREEZE: - callback = noirq ? pm->freeze_noirq : pm->freeze; - break; - case PM_EVENT_HIBERNATE: - callback = noirq ? pm->poweroff_noirq : pm->poweroff; - break; - case PM_EVENT_RESUME: - callback = noirq ? pm->resume_noirq : pm->resume; - break; - case PM_EVENT_THAW: - callback = noirq ? pm->thaw_noirq : pm->thaw; - break; - case PM_EVENT_RESTORE: - callback = noirq ? pm->restore_noirq : pm->restore; - break; - default: - callback = NULL; - break; - } - return callback ? callback(dev) : 0; + return pm && pm->suspend_noirq ? pm->suspend_noirq(dev) : 0; } +EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq); /** - * pm_generic_suspend_noirq - Generic suspend_noirq callback for subsystems. + * pm_generic_suspend_late - Generic suspend_late callback for subsystems. * @dev: Device to suspend. */ -int pm_generic_suspend_noirq(struct device *dev) +int pm_generic_suspend_late(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_SUSPEND, true); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->suspend_late ? pm->suspend_late(dev) : 0; } -EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq); +EXPORT_SYMBOL_GPL(pm_generic_suspend_late); /** * pm_generic_suspend - Generic suspend callback for subsystems. @@ -152,7 +121,9 @@ EXPORT_SYMBOL_GPL(pm_generic_suspend_noirq); */ int pm_generic_suspend(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_SUSPEND, false); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->suspend ? pm->suspend(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_suspend); @@ -162,17 +133,33 @@ EXPORT_SYMBOL_GPL(pm_generic_suspend); */ int pm_generic_freeze_noirq(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_FREEZE, true); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->freeze_noirq ? pm->freeze_noirq(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_freeze_noirq); +/** + * pm_generic_freeze_late - Generic freeze_late callback for subsystems. + * @dev: Device to freeze. + */ +int pm_generic_freeze_late(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->freeze_late ? pm->freeze_late(dev) : 0; +} +EXPORT_SYMBOL_GPL(pm_generic_freeze_late); + /** * pm_generic_freeze - Generic freeze callback for subsystems. * @dev: Device to freeze. */ int pm_generic_freeze(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_FREEZE, false); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->freeze ? pm->freeze(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_freeze); @@ -182,17 +169,33 @@ EXPORT_SYMBOL_GPL(pm_generic_freeze); */ int pm_generic_poweroff_noirq(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_HIBERNATE, true); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->poweroff_noirq ? pm->poweroff_noirq(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_poweroff_noirq); +/** + * pm_generic_poweroff_late - Generic poweroff_late callback for subsystems. + * @dev: Device to handle. + */ +int pm_generic_poweroff_late(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->poweroff_late ? pm->poweroff_late(dev) : 0; +} +EXPORT_SYMBOL_GPL(pm_generic_poweroff_late); + /** * pm_generic_poweroff - Generic poweroff callback for subsystems. * @dev: Device to handle. */ int pm_generic_poweroff(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_HIBERNATE, false); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->poweroff ? pm->poweroff(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_poweroff); @@ -202,17 +205,33 @@ EXPORT_SYMBOL_GPL(pm_generic_poweroff); */ int pm_generic_thaw_noirq(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_THAW, true); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->thaw_noirq ? pm->thaw_noirq(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_thaw_noirq); +/** + * pm_generic_thaw_early - Generic thaw_early callback for subsystems. + * @dev: Device to thaw. + */ +int pm_generic_thaw_early(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->thaw_early ? pm->thaw_early(dev) : 0; +} +EXPORT_SYMBOL_GPL(pm_generic_thaw_early); + /** * pm_generic_thaw - Generic thaw callback for subsystems. * @dev: Device to thaw. */ int pm_generic_thaw(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_THAW, false); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->thaw ? pm->thaw(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_thaw); @@ -222,17 +241,33 @@ EXPORT_SYMBOL_GPL(pm_generic_thaw); */ int pm_generic_resume_noirq(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_RESUME, true); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->resume_noirq ? pm->resume_noirq(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_resume_noirq); +/** + * pm_generic_resume_early - Generic resume_early callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_resume_early(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->resume_early ? pm->resume_early(dev) : 0; +} +EXPORT_SYMBOL_GPL(pm_generic_resume_early); + /** * pm_generic_resume - Generic resume callback for subsystems. * @dev: Device to resume. */ int pm_generic_resume(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_RESUME, false); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->resume ? pm->resume(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_resume); @@ -242,17 +277,33 @@ EXPORT_SYMBOL_GPL(pm_generic_resume); */ int pm_generic_restore_noirq(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_RESTORE, true); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->restore_noirq ? pm->restore_noirq(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_restore_noirq); +/** + * pm_generic_restore_early - Generic restore_early callback for subsystems. + * @dev: Device to resume. + */ +int pm_generic_restore_early(struct device *dev) +{ + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->restore_early ? pm->restore_early(dev) : 0; +} +EXPORT_SYMBOL_GPL(pm_generic_restore_early); + /** * pm_generic_restore - Generic restore callback for subsystems. * @dev: Device to restore. */ int pm_generic_restore(struct device *dev) { - return __pm_generic_call(dev, PM_EVENT_RESTORE, false); + const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; + + return pm && pm->restore ? pm->restore(dev) : 0; } EXPORT_SYMBOL_GPL(pm_generic_restore); diff --git a/include/linux/pm.h b/include/linux/pm.h index c68e1f22ac95..73c610573a74 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -632,17 +632,23 @@ extern void __suspend_report_result(const char *function, void *fn, int ret); extern int device_pm_wait_for_dev(struct device *sub, struct device *dev); extern int pm_generic_prepare(struct device *dev); +extern int pm_generic_suspend_late(struct device *dev); extern int pm_generic_suspend_noirq(struct device *dev); extern int pm_generic_suspend(struct device *dev); +extern int pm_generic_resume_early(struct device *dev); extern int pm_generic_resume_noirq(struct device *dev); extern int pm_generic_resume(struct device *dev); extern int pm_generic_freeze_noirq(struct device *dev); +extern int pm_generic_freeze_late(struct device *dev); extern int pm_generic_freeze(struct device *dev); extern int pm_generic_thaw_noirq(struct device *dev); +extern int pm_generic_thaw_early(struct device *dev); extern int pm_generic_thaw(struct device *dev); extern int pm_generic_restore_noirq(struct device *dev); +extern int pm_generic_restore_early(struct device *dev); extern int pm_generic_restore(struct device *dev); extern int pm_generic_poweroff_noirq(struct device *dev); +extern int pm_generic_poweroff_late(struct device *dev); extern int pm_generic_poweroff(struct device *dev); extern void pm_generic_complete(struct device *dev); -- cgit v1.2.3 From 7c95149b7f1f61201b12c73c4862a41bf2428961 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 11 Feb 2012 00:00:11 +0100 Subject: PM / Sleep: Initialize wakeup source locks in wakeup_source_add() Initialize wakeup source locks in wakeup_source_add() instead of wakeup_source_create(), because otherwise the locks of the wakeup sources that haven't been allocated with wakeup_source_create() aren't initialized and handled properly. Signed-off-by: Rafael J. Wysocki --- drivers/base/power/wakeup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base') diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index caf995fb774b..6e591a8a49da 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -64,7 +64,6 @@ struct wakeup_source *wakeup_source_create(const char *name) if (!ws) return NULL; - spin_lock_init(&ws->lock); if (name) ws->name = kstrdup(name, GFP_KERNEL); @@ -105,6 +104,7 @@ void wakeup_source_add(struct wakeup_source *ws) if (WARN_ON(!ws)) return; + spin_lock_init(&ws->lock); setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws); ws->active = false; -- cgit v1.2.3 From d94aff87826ee6aa43032f4c0263482913f4e2c8 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 17 Feb 2012 23:39:20 +0100 Subject: PM / Sleep: Fix possible infinite loop during wakeup source destruction MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If wakeup_source_destroy() is called for an active wakeup source that is never deactivated, it will spin forever. To prevent that from happening, make wakeup_source_destroy() call __pm_relax() for the wakeup source object it is about to free instead of waiting until it will be deactivated by someone else. However, for this to work it also needs to make sure that the timer function will not be executed after the final __pm_relax(), so make it run del_timer_sync() on the wakeup source's timer beforehand. Additionally, update the kerneldoc comment to document the requirement that __pm_stay_awake() and __pm_wakeup_event() must not be run in parallel with wakeup_source_destroy(). Reported-by: Arve Hjønnevåg Signed-off-by: Rafael J. Wysocki --- drivers/base/power/wakeup.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index 6e591a8a49da..d279f462d624 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -74,22 +74,17 @@ EXPORT_SYMBOL_GPL(wakeup_source_create); /** * wakeup_source_destroy - Destroy a struct wakeup_source object. * @ws: Wakeup source to destroy. + * + * Callers must ensure that __pm_stay_awake() or __pm_wakeup_event() will never + * be run in parallel with this function for the same wakeup source object. */ void wakeup_source_destroy(struct wakeup_source *ws) { if (!ws) return; - spin_lock_irq(&ws->lock); - while (ws->active) { - spin_unlock_irq(&ws->lock); - - schedule_timeout_interruptible(msecs_to_jiffies(TIMEOUT)); - - spin_lock_irq(&ws->lock); - } - spin_unlock_irq(&ws->lock); - + del_timer_sync(&ws->timer); + __pm_relax(ws); kfree(ws->name); kfree(ws); } -- cgit v1.2.3 From da863cddd831b0f4bf2d067f8b75254f1be94590 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 17 Feb 2012 23:39:33 +0100 Subject: PM / Sleep: Fix race conditions related to wakeup source timer function MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If __pm_wakeup_event() has been used (with a nonzero timeout) to report a wakeup event and then __pm_relax() immediately followed by __pm_stay_awake() is called or __pm_wakeup_event() is called once again for the same wakeup source object before its timer expires, the timer function pm_wakeup_timer_fn() may still be run as a result of the previous __pm_wakeup_event() call. In either of those cases it may mistakenly deactivate the wakeup source that has just been activated. To prevent that from happening, make wakeup_source_deactivate() clear the wakeup source's timer_expires field and make pm_wakeup_timer_fn() check if timer_expires is different from zero and if it's not in future before calling wakeup_source_deactivate() (if timer_expires is 0, it means that the timer has just been deleted and if timer_expires is in future, it means that the timer has just been rescheduled to a different time). Reported-by: Arve Hjønnevåg Signed-off-by: Rafael J. Wysocki --- drivers/base/power/wakeup.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index d279f462d624..b38bb9afb719 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -433,6 +433,7 @@ static void wakeup_source_deactivate(struct wakeup_source *ws) ws->max_time = duration; del_timer(&ws->timer); + ws->timer_expires = 0; /* * Increment the counter of registered wakeup events and decrement the @@ -487,11 +488,22 @@ EXPORT_SYMBOL_GPL(pm_relax); * pm_wakeup_timer_fn - Delayed finalization of a wakeup event. * @data: Address of the wakeup source object associated with the event source. * - * Call __pm_relax() for the wakeup source whose address is stored in @data. + * Call wakeup_source_deactivate() for the wakeup source whose address is stored + * in @data if it is currently active and its timer has not been canceled and + * the expiration time of the timer is not in future. */ static void pm_wakeup_timer_fn(unsigned long data) { - __pm_relax((struct wakeup_source *)data); + struct wakeup_source *ws = (struct wakeup_source *)data; + unsigned long flags; + + spin_lock_irqsave(&ws->lock, flags); + + if (ws->active && ws->timer_expires + && time_after_eq(jiffies, ws->timer_expires)) + wakeup_source_deactivate(ws); + + spin_unlock_irqrestore(&ws->lock, flags); } /** -- cgit v1.2.3 From 4782e1654bdbd30cf307da090b3c4f70157477cb Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 17 Feb 2012 23:39:39 +0100 Subject: PM / Sleep: Make __pm_stay_awake() delete wakeup source timers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If __pm_stay_awake() is called after __pm_wakeup_event() for the same wakep source object before its timer expires, it won't cancel the timer, so the wakeup source will be deactivated from the timer function as scheduled by __pm_wakeup_event(). In that case __pm_stay_awake() doesn't have any effect beyond incrementing the wakeup source's event_count field, although it should cancel the timer and make the wakeup source stay active until __pm_relax() is called for it. To fix this problem make __pm_stay_awake() delete the wakeup source's timer and ensure that it won't be deactivated from the timer funtion afterwards by clearing its timer_expires field. Reported-by: Arve Hjønnevåg Signed-off-by: Rafael J. Wysocki --- drivers/base/power/wakeup.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index b38bb9afb719..7c5ab70b9ef3 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -344,7 +344,6 @@ static void wakeup_source_activate(struct wakeup_source *ws) { ws->active = true; ws->active_count++; - ws->timer_expires = jiffies; ws->last_time = ktime_get(); /* Increment the counter of events in progress. */ @@ -365,9 +364,14 @@ void __pm_stay_awake(struct wakeup_source *ws) return; spin_lock_irqsave(&ws->lock, flags); + ws->event_count++; if (!ws->active) wakeup_source_activate(ws); + + del_timer(&ws->timer); + ws->timer_expires = 0; + spin_unlock_irqrestore(&ws->lock, flags); } EXPORT_SYMBOL_GPL(__pm_stay_awake); @@ -541,7 +545,7 @@ void __pm_wakeup_event(struct wakeup_source *ws, unsigned int msec) if (!expires) expires = 1; - if (time_after(expires, ws->timer_expires)) { + if (!ws->timer_expires || time_after(expires, ws->timer_expires)) { mod_timer(&ws->timer, expires); ws->timer_expires = expires; } -- cgit v1.2.3 From 8671bbc1bd0442ef0eab27f7d56216431c490820 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 21 Feb 2012 23:47:56 +0100 Subject: PM / Sleep: Add more wakeup source initialization routines MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The existing wakeup source initialization routines are not particularly useful for wakeup sources that aren't created by wakeup_source_create(), because their users have to open code filling the objects with zeros and setting their names. For this reason, introduce routines that can be used for initializing, for example, static wakeup source objects. Requested-by: Arve Hjønnevåg Signed-off-by: Rafael J. Wysocki --- drivers/base/power/wakeup.c | 50 +++++++++++++++++++++++++++++++++++++-------- include/linux/pm_wakeup.h | 22 +++++++++++++++++++- 2 files changed, 62 insertions(+), 10 deletions(-) (limited to 'drivers/base') diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index 7c5ab70b9ef3..2a3e581b8dcd 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -52,6 +52,23 @@ static void pm_wakeup_timer_fn(unsigned long data); static LIST_HEAD(wakeup_sources); +/** + * wakeup_source_prepare - Prepare a new wakeup source for initialization. + * @ws: Wakeup source to prepare. + * @name: Pointer to the name of the new wakeup source. + * + * Callers must ensure that the @name string won't be freed when @ws is still in + * use. + */ +void wakeup_source_prepare(struct wakeup_source *ws, const char *name) +{ + if (ws) { + memset(ws, 0, sizeof(*ws)); + ws->name = name; + } +} +EXPORT_SYMBOL_GPL(wakeup_source_prepare); + /** * wakeup_source_create - Create a struct wakeup_source object. * @name: Name of the new wakeup source. @@ -60,31 +77,44 @@ struct wakeup_source *wakeup_source_create(const char *name) { struct wakeup_source *ws; - ws = kzalloc(sizeof(*ws), GFP_KERNEL); + ws = kmalloc(sizeof(*ws), GFP_KERNEL); if (!ws) return NULL; - if (name) - ws->name = kstrdup(name, GFP_KERNEL); - + wakeup_source_prepare(ws, name ? kstrdup(name, GFP_KERNEL) : NULL); return ws; } EXPORT_SYMBOL_GPL(wakeup_source_create); /** - * wakeup_source_destroy - Destroy a struct wakeup_source object. - * @ws: Wakeup source to destroy. + * wakeup_source_drop - Prepare a struct wakeup_source object for destruction. + * @ws: Wakeup source to prepare for destruction. * * Callers must ensure that __pm_stay_awake() or __pm_wakeup_event() will never * be run in parallel with this function for the same wakeup source object. */ -void wakeup_source_destroy(struct wakeup_source *ws) +void wakeup_source_drop(struct wakeup_source *ws) { if (!ws) return; del_timer_sync(&ws->timer); __pm_relax(ws); +} +EXPORT_SYMBOL_GPL(wakeup_source_drop); + +/** + * wakeup_source_destroy - Destroy a struct wakeup_source object. + * @ws: Wakeup source to destroy. + * + * Use only for wakeup source objects created with wakeup_source_create(). + */ +void wakeup_source_destroy(struct wakeup_source *ws) +{ + if (!ws) + return; + + wakeup_source_drop(ws); kfree(ws->name); kfree(ws); } @@ -147,8 +177,10 @@ EXPORT_SYMBOL_GPL(wakeup_source_register); */ void wakeup_source_unregister(struct wakeup_source *ws) { - wakeup_source_remove(ws); - wakeup_source_destroy(ws); + if (ws) { + wakeup_source_remove(ws); + wakeup_source_destroy(ws); + } } EXPORT_SYMBOL_GPL(wakeup_source_unregister); diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h index a32da962d693..d9f05113e5fb 100644 --- a/include/linux/pm_wakeup.h +++ b/include/linux/pm_wakeup.h @@ -41,7 +41,7 @@ * @active: Status of the wakeup source. */ struct wakeup_source { - char *name; + const char *name; struct list_head entry; spinlock_t lock; struct timer_list timer; @@ -73,7 +73,9 @@ static inline bool device_may_wakeup(struct device *dev) } /* drivers/base/power/wakeup.c */ +extern void wakeup_source_prepare(struct wakeup_source *ws, const char *name); extern struct wakeup_source *wakeup_source_create(const char *name); +extern void wakeup_source_drop(struct wakeup_source *ws); extern void wakeup_source_destroy(struct wakeup_source *ws); extern void wakeup_source_add(struct wakeup_source *ws); extern void wakeup_source_remove(struct wakeup_source *ws); @@ -103,11 +105,16 @@ static inline bool device_can_wakeup(struct device *dev) return dev->power.can_wakeup; } +static inline void wakeup_source_prepare(struct wakeup_source *ws, + const char *name) {} + static inline struct wakeup_source *wakeup_source_create(const char *name) { return NULL; } +static inline void wakeup_source_drop(struct wakeup_source *ws) {} + static inline void wakeup_source_destroy(struct wakeup_source *ws) {} static inline void wakeup_source_add(struct wakeup_source *ws) {} @@ -165,4 +172,17 @@ static inline void pm_wakeup_event(struct device *dev, unsigned int msec) {} #endif /* !CONFIG_PM_SLEEP */ +static inline void wakeup_source_init(struct wakeup_source *ws, + const char *name) +{ + wakeup_source_prepare(ws, name); + wakeup_source_add(ws); +} + +static inline void wakeup_source_trash(struct wakeup_source *ws) +{ + wakeup_source_remove(ws); + wakeup_source_drop(ws); +} + #endif /* _LINUX_PM_WAKEUP_H */ -- cgit v1.2.3