From 1eede070a59e1cc73da51e1aaa00d9ab86572cfc Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 20 May 2008 23:00:01 +0200 Subject: Introduce new top level suspend and hibernation callbacks Introduce 'struct pm_ops' and 'struct pm_ext_ops' ('ext' meaning 'extended') representing suspend and hibernation operations for bus types, device classes, device types and device drivers. Modify the PM core to use 'struct pm_ops' and 'struct pm_ext_ops' objects, if defined, instead of the ->suspend(), ->resume(), ->suspend_late(), and ->resume_early() callbacks (the old callbacks will be considered as legacy and gradually phased out). The main purpose of doing this is to separate suspend (aka S2RAM and standby) callbacks from hibernation callbacks in such a way that the new callbacks won't take arguments and the semantics of each of them will be clearly specified. This has been requested for multiple times by many people, including Linus himself, and the reason is that within the current scheme if ->resume() is called, for example, it's difficult to say why it's been called (ie. is it a resume from RAM or from hibernation or a suspend/hibernation failure etc.?). The second purpose is to make the suspend/hibernation callbacks more flexible so that device drivers can handle more than they can within the current scheme. For example, some drivers may need to prevent new children of the device from being registered before their ->suspend() callbacks are executed or they may want to carry out some operations requiring the availability of some other devices, not directly bound via the parent-child relationship, in order to prepare for the execution of ->suspend(), etc. Ultimately, we'd like to stop using the freezing of tasks for suspend and therefore the drivers' suspend/hibernation code will have to take care of the handling of the user space during suspend/hibernation. That, in turn, would be difficult within the current scheme, without the new ->prepare() and ->complete() callbacks. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Jesse Barnes --- drivers/base/power/main.c | 675 +++++++++++++++++++++++++++++++++++----------- 1 file changed, 524 insertions(+), 151 deletions(-) (limited to 'drivers/base/power/main.c') diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 45cc3d9eacb..d571204aaff 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -12,11 +12,9 @@ * and add it to the list of power-controlled devices. sysfs entries for * controlling device power management will also be added. * - * A different set of lists than the global subsystem list are used to - * keep track of power info because we use different lists to hold - * devices based on what stage of the power management process they - * are in. The power domain dependencies may also differ from the - * ancestral dependencies that the subsystem list maintains. + * A separate list is used for keeping track of power info, because the power + * domain dependencies may differ from the ancestral dependencies that the + * subsystem list maintains. */ #include @@ -30,31 +28,40 @@ #include "power.h" /* - * The entries in the dpm_active list are in a depth first order, simply + * The entries in the dpm_list list are in a depth first order, simply * because children are guaranteed to be discovered after parents, and * are inserted at the back of the list on discovery. * - * All the other lists are kept in the same order, for consistency. - * However the lists aren't always traversed in the same order. - * Semaphores must be acquired from the top (i.e., front) down - * and released in the opposite order. Devices must be suspended - * from the bottom (i.e., end) up and resumed in the opposite order. - * That way no parent will be suspended while it still has an active - * child. - * * Since device_pm_add() may be called with a device semaphore held, * we must never try to acquire a device semaphore while holding * dpm_list_mutex. */ -LIST_HEAD(dpm_active); -static LIST_HEAD(dpm_off); -static LIST_HEAD(dpm_off_irq); +LIST_HEAD(dpm_list); static DEFINE_MUTEX(dpm_list_mtx); -/* 'true' if all devices have been suspended, protected by dpm_list_mtx */ -static bool all_sleeping; +/* + * Set once the preparation of devices for a PM transition has started, reset + * before starting to resume devices. Protected by dpm_list_mtx. + */ +static bool transition_started; + +/** + * device_pm_lock - lock the list of active devices used by the PM core + */ +void device_pm_lock(void) +{ + mutex_lock(&dpm_list_mtx); +} + +/** + * device_pm_unlock - unlock the list of active devices used by the PM core + */ +void device_pm_unlock(void) +{ + mutex_unlock(&dpm_list_mtx); +} /** * device_pm_add - add a device to the list of active devices @@ -68,17 +75,25 @@ int device_pm_add(struct device *dev) dev->bus ? dev->bus->name : "No Bus", kobject_name(&dev->kobj)); mutex_lock(&dpm_list_mtx); - if ((dev->parent && dev->parent->power.sleeping) || all_sleeping) { - if (dev->parent->power.sleeping) - dev_warn(dev, "parent %s is sleeping\n", + if (dev->parent) { + if (dev->parent->power.status >= DPM_SUSPENDING) { + dev_warn(dev, "parent %s is sleeping, will not add\n", dev->parent->bus_id); - else - dev_warn(dev, "all devices are sleeping\n"); + WARN_ON(true); + } + } else if (transition_started) { + /* + * We refuse to register parentless devices while a PM + * transition is in progress in order to avoid leaving them + * unhandled down the road + */ WARN_ON(true); } error = dpm_sysfs_add(dev); - if (!error) - list_add_tail(&dev->power.entry, &dpm_active); + if (!error) { + dev->power.status = DPM_ON; + list_add_tail(&dev->power.entry, &dpm_list); + } mutex_unlock(&dpm_list_mtx); return error; } @@ -100,73 +115,243 @@ void device_pm_remove(struct device *dev) mutex_unlock(&dpm_list_mtx); } +/** + * pm_op - execute the PM operation appropiate for given PM event + * @dev: Device. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + */ +static int pm_op(struct device *dev, struct pm_ops *ops, pm_message_t state) +{ + int error = 0; + + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + if (ops->suspend) { + error = ops->suspend(dev); + suspend_report_result(ops->suspend, error); + } + break; + case PM_EVENT_RESUME: + if (ops->resume) { + error = ops->resume(dev); + suspend_report_result(ops->resume, error); + } + break; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATION + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + if (ops->freeze) { + error = ops->freeze(dev); + suspend_report_result(ops->freeze, error); + } + break; + case PM_EVENT_HIBERNATE: + if (ops->poweroff) { + error = ops->poweroff(dev); + suspend_report_result(ops->poweroff, error); + } + break; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + if (ops->thaw) { + error = ops->thaw(dev); + suspend_report_result(ops->thaw, error); + } + break; + case PM_EVENT_RESTORE: + if (ops->restore) { + error = ops->restore(dev); + suspend_report_result(ops->restore, error); + } + break; +#endif /* CONFIG_HIBERNATION */ + default: + error = -EINVAL; + } + return error; +} + +/** + * pm_noirq_op - execute the PM operation appropiate for given PM event + * @dev: Device. + * @ops: PM operations to choose from. + * @state: PM transition of the system being carried out. + * + * The operation is executed with interrupts disabled by the only remaining + * functional CPU in the system. + */ +static int pm_noirq_op(struct device *dev, struct pm_ext_ops *ops, + pm_message_t state) +{ + int error = 0; + + switch (state.event) { +#ifdef CONFIG_SUSPEND + case PM_EVENT_SUSPEND: + if (ops->suspend_noirq) { + error = ops->suspend_noirq(dev); + suspend_report_result(ops->suspend_noirq, error); + } + break; + case PM_EVENT_RESUME: + if (ops->resume_noirq) { + error = ops->resume_noirq(dev); + suspend_report_result(ops->resume_noirq, error); + } + break; +#endif /* CONFIG_SUSPEND */ +#ifdef CONFIG_HIBERNATION + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + if (ops->freeze_noirq) { + error = ops->freeze_noirq(dev); + suspend_report_result(ops->freeze_noirq, error); + } + break; + case PM_EVENT_HIBERNATE: + if (ops->poweroff_noirq) { + error = ops->poweroff_noirq(dev); + suspend_report_result(ops->poweroff_noirq, error); + } + break; + case PM_EVENT_THAW: + case PM_EVENT_RECOVER: + if (ops->thaw_noirq) { + error = ops->thaw_noirq(dev); + suspend_report_result(ops->thaw_noirq, error); + } + break; + case PM_EVENT_RESTORE: + if (ops->restore_noirq) { + error = ops->restore_noirq(dev); + suspend_report_result(ops->restore_noirq, error); + } + break; +#endif /* CONFIG_HIBERNATION */ + default: + error = -EINVAL; + } + return error; +} + +static char *pm_verb(int event) +{ + switch (event) { + case PM_EVENT_SUSPEND: + return "suspend"; + case PM_EVENT_RESUME: + return "resume"; + case PM_EVENT_FREEZE: + return "freeze"; + case PM_EVENT_QUIESCE: + return "quiesce"; + case PM_EVENT_HIBERNATE: + return "hibernate"; + case PM_EVENT_THAW: + return "thaw"; + case PM_EVENT_RESTORE: + return "restore"; + case PM_EVENT_RECOVER: + return "recover"; + default: + return "(unknown PM event)"; + } +} + +static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info) +{ + dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event), + ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ? + ", may wakeup" : ""); +} + +static void pm_dev_err(struct device *dev, pm_message_t state, char *info, + int error) +{ + printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n", + kobject_name(&dev->kobj), pm_verb(state.event), info, error); +} + /*------------------------- Resume routines -------------------------*/ /** - * resume_device_early - Power on one device (early resume). + * resume_device_noirq - Power on one device (early resume). * @dev: Device. + * @state: PM transition of the system being carried out. * * Must be called with interrupts disabled. */ -static int resume_device_early(struct device *dev) +static int resume_device_noirq(struct device *dev, pm_message_t state) { int error = 0; TRACE_DEVICE(dev); TRACE_RESUME(0); - if (dev->bus && dev->bus->resume_early) { - dev_dbg(dev, "EARLY resume\n"); + if (!dev->bus) + goto End; + + if (dev->bus->pm) { + pm_dev_dbg(dev, state, "EARLY "); + error = pm_noirq_op(dev, dev->bus->pm, state); + } else if (dev->bus->resume_early) { + pm_dev_dbg(dev, state, "legacy EARLY "); error = dev->bus->resume_early(dev); } - + End: TRACE_RESUME(error); return error; } /** * dpm_power_up - Power on all regular (non-sysdev) devices. + * @state: PM transition of the system being carried out. * - * Walk the dpm_off_irq list and power each device up. This - * is used for devices that required they be powered down with - * interrupts disabled. As devices are powered on, they are moved - * to the dpm_off list. + * Execute the appropriate "noirq resume" callback for all devices marked + * as DPM_OFF_IRQ. * * Must be called with interrupts disabled and only one CPU running. */ -static void dpm_power_up(void) +static void dpm_power_up(pm_message_t state) { + struct device *dev; - while (!list_empty(&dpm_off_irq)) { - struct list_head *entry = dpm_off_irq.next; - struct device *dev = to_device(entry); + list_for_each_entry(dev, &dpm_list, power.entry) + if (dev->power.status > DPM_OFF) { + int error; - list_move_tail(entry, &dpm_off); - resume_device_early(dev); - } + dev->power.status = DPM_OFF; + error = resume_device_noirq(dev, state); + if (error) + pm_dev_err(dev, state, " early", error); + } } /** * device_power_up - Turn on all devices that need special attention. + * @state: PM transition of the system being carried out. * * Power on system devices, then devices that required we shut them down * with interrupts disabled. * * Must be called with interrupts disabled. */ -void device_power_up(void) +void device_power_up(pm_message_t state) { sysdev_resume(); - dpm_power_up(); + dpm_power_up(state); } EXPORT_SYMBOL_GPL(device_power_up); /** * resume_device - Restore state for one device. * @dev: Device. - * + * @state: PM transition of the system being carried out. */ -static int resume_device(struct device *dev) +static int resume_device(struct device *dev, pm_message_t state) { int error = 0; @@ -175,21 +360,40 @@ static int resume_device(struct device *dev) down(&dev->sem); - if (dev->bus && dev->bus->resume) { - dev_dbg(dev,"resuming\n"); - error = dev->bus->resume(dev); + if (dev->bus) { + if (dev->bus->pm) { + pm_dev_dbg(dev, state, ""); + error = pm_op(dev, &dev->bus->pm->base, state); + } else if (dev->bus->resume) { + pm_dev_dbg(dev, state, "legacy "); + error = dev->bus->resume(dev); + } + if (error) + goto End; } - if (!error && dev->type && dev->type->resume) { - dev_dbg(dev,"resuming\n"); - error = dev->type->resume(dev); + if (dev->type) { + if (dev->type->pm) { + pm_dev_dbg(dev, state, "type "); + error = pm_op(dev, dev->type->pm, state); + } else if (dev->type->resume) { + pm_dev_dbg(dev, state, "legacy type "); + error = dev->type->resume(dev); + } + if (error) + goto End; } - if (!error && dev->class && dev->class->resume) { - dev_dbg(dev,"class resume\n"); - error = dev->class->resume(dev); + if (dev->class) { + if (dev->class->pm) { + pm_dev_dbg(dev, state, "class "); + error = pm_op(dev, dev->class->pm, state); + } else if (dev->class->resume) { + pm_dev_dbg(dev, state, "legacy class "); + error = dev->class->resume(dev); + } } - + End: up(&dev->sem); TRACE_RESUME(error); @@ -198,78 +402,161 @@ static int resume_device(struct device *dev) /** * dpm_resume - Resume every device. + * @state: PM transition of the system being carried out. * - * Resume the devices that have either not gone through - * the late suspend, or that did go through it but also - * went through the early resume. + * Execute the appropriate "resume" callback for all devices the status of + * which indicates that they are inactive. + */ +static void dpm_resume(pm_message_t state) +{ + struct list_head list; + + INIT_LIST_HEAD(&list); + mutex_lock(&dpm_list_mtx); + transition_started = false; + while (!list_empty(&dpm_list)) { + struct device *dev = to_device(dpm_list.next); + + get_device(dev); + if (dev->power.status >= DPM_OFF) { + int error; + + dev->power.status = DPM_RESUMING; + mutex_unlock(&dpm_list_mtx); + + error = resume_device(dev, state); + + mutex_lock(&dpm_list_mtx); + if (error) + pm_dev_err(dev, state, "", error); + } else if (dev->power.status == DPM_SUSPENDING) { + /* Allow new children of the device to be registered */ + dev->power.status = DPM_RESUMING; + } + if (!list_empty(&dev->power.entry)) + list_move_tail(&dev->power.entry, &list); + put_device(dev); + } + list_splice(&list, &dpm_list); + mutex_unlock(&dpm_list_mtx); +} + +/** + * complete_device - Complete a PM transition for given device + * @dev: Device. + * @state: PM transition of the system being carried out. + */ +static void complete_device(struct device *dev, pm_message_t state) +{ + down(&dev->sem); + + if (dev->class && dev->class->pm && dev->class->pm->complete) { + pm_dev_dbg(dev, state, "completing class "); + dev->class->pm->complete(dev); + } + + if (dev->type && dev->type->pm && dev->type->pm->complete) { + pm_dev_dbg(dev, state, "completing type "); + dev->type->pm->complete(dev); + } + + if (dev->bus && dev->bus->pm && dev->bus->pm->base.complete) { + pm_dev_dbg(dev, state, "completing "); + dev->bus->pm->base.complete(dev); + } + + up(&dev->sem); +} + +/** + * dpm_complete - Complete a PM transition for all devices. + * @state: PM transition of the system being carried out. * - * Take devices from the dpm_off_list, resume them, - * and put them on the dpm_locked list. + * Execute the ->complete() callbacks for all devices that are not marked + * as DPM_ON. */ -static void dpm_resume(void) +static void dpm_complete(pm_message_t state) { + struct list_head list; + + INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); - all_sleeping = false; - while(!list_empty(&dpm_off)) { - struct list_head *entry = dpm_off.next; - struct device *dev = to_device(entry); + while (!list_empty(&dpm_list)) { + struct device *dev = to_device(dpm_list.prev); - list_move_tail(entry, &dpm_active); - dev->power.sleeping = false; - mutex_unlock(&dpm_list_mtx); - resume_device(dev); - mutex_lock(&dpm_list_mtx); + get_device(dev); + if (dev->power.status > DPM_ON) { + dev->power.status = DPM_ON; + mutex_unlock(&dpm_list_mtx); + + complete_device(dev, state); + + mutex_lock(&dpm_list_mtx); + } + if (!list_empty(&dev->power.entry)) + list_move(&dev->power.entry, &list); + put_device(dev); } + list_splice(&list, &dpm_list); mutex_unlock(&dpm_list_mtx); } /** * device_resume - Restore state of each device in system. + * @state: PM transition of the system being carried out. * * Resume all the devices, unlock them all, and allow new * devices to be registered once again. */ -void device_resume(void) +void device_resume(pm_message_t state) { might_sleep(); - dpm_resume(); + dpm_resume(state); + dpm_complete(state); } EXPORT_SYMBOL_GPL(device_resume); /*------------------------- Suspend routines -------------------------*/ -static inline char *suspend_verb(u32 event) +/** + * resume_event - return a PM message representing the resume event + * corresponding to given sleep state. + * @sleep_state: PM message representing a sleep state. + */ +static pm_message_t resume_event(pm_message_t sleep_state) { - switch (event) { - case PM_EVENT_SUSPEND: return "suspend"; - case PM_EVENT_FREEZE: return "freeze"; - case PM_EVENT_PRETHAW: return "prethaw"; - default: return "(unknown suspend event)"; + switch (sleep_state.event) { + case PM_EVENT_SUSPEND: + return PMSG_RESUME; + case PM_EVENT_FREEZE: + case PM_EVENT_QUIESCE: + return PMSG_RECOVER; + case PM_EVENT_HIBERNATE: + return PMSG_RESTORE; } -} - -static void -suspend_device_dbg(struct device *dev, pm_message_t state, char *info) -{ - dev_dbg(dev, "%s%s%s\n", info, suspend_verb(state.event), - ((state.event == PM_EVENT_SUSPEND) && device_may_wakeup(dev)) ? - ", may wakeup" : ""); + return PMSG_ON; } /** - * suspend_device_late - Shut down one device (late suspend). + * suspend_device_noirq - Shut down one device (late suspend). * @dev: Device. - * @state: Power state device is entering. + * @state: PM transition of the system being carried out. * * This is called with interrupts off and only a single CPU running. */ -static int suspend_device_late(struct device *dev, pm_message_t state) +static int suspend_device_noirq(struct device *dev, pm_message_t state) { int error = 0; - if (dev->bus && dev->bus->suspend_late) { - suspend_device_dbg(dev, state, "LATE "); + if (!dev->bus) + return 0; + + if (dev->bus->pm) { + pm_dev_dbg(dev, state, "LATE "); + error = pm_noirq_op(dev, dev->bus->pm, state); + } else if (dev->bus->suspend_late) { + pm_dev_dbg(dev, state, "legacy LATE "); error = dev->bus->suspend_late(dev, state); suspend_report_result(dev->bus->suspend_late, error); } @@ -278,37 +565,30 @@ static int suspend_device_late(struct device *dev, pm_message_t state) /** * device_power_down - Shut down special devices. - * @state: Power state to enter. + * @state: PM transition of the system being carried out. * - * Power down devices that require interrupts to be disabled - * and move them from the dpm_off list to the dpm_off_irq list. + * Power down devices that require interrupts to be disabled. * Then power down system devices. * * Must be called with interrupts disabled and only one CPU running. */ int device_power_down(pm_message_t state) { + struct device *dev; int error = 0; - while (!list_empty(&dpm_off)) { - struct list_head *entry = dpm_off.prev; - struct device *dev = to_device(entry); - - error = suspend_device_late(dev, state); + list_for_each_entry_reverse(dev, &dpm_list, power.entry) { + error = suspend_device_noirq(dev, state); if (error) { - printk(KERN_ERR "Could not power down device %s: " - "error %d\n", - kobject_name(&dev->kobj), error); + pm_dev_err(dev, state, " late", error); break; } - if (!list_empty(&dev->power.entry)) - list_move(&dev->power.entry, &dpm_off_irq); + dev->power.status = DPM_OFF_IRQ; } - if (!error) error = sysdev_suspend(state); if (error) - dpm_power_up(); + dpm_power_up(resume_event(state)); return error; } EXPORT_SYMBOL_GPL(device_power_down); @@ -316,7 +596,7 @@ EXPORT_SYMBOL_GPL(device_power_down); /** * suspend_device - Save state of one device. * @dev: Device. - * @state: Power state device is entering. + * @state: PM transition of the system being carried out. */ static int suspend_device(struct device *dev, pm_message_t state) { @@ -324,24 +604,43 @@ static int suspend_device(struct device *dev, pm_message_t state) down(&dev->sem); - if (dev->class && dev->class->suspend) { - suspend_device_dbg(dev, state, "class "); - error = dev->class->suspend(dev, state); - suspend_report_result(dev->class->suspend, error); + if (dev->class) { + if (dev->class->pm) { + pm_dev_dbg(dev, state, "class "); + error = pm_op(dev, dev->class->pm, state); + } else if (dev->class->suspend) { + pm_dev_dbg(dev, state, "legacy class "); + error = dev->class->suspend(dev, state); + suspend_report_result(dev->class->suspend, error); + } + if (error) + goto End; } - if (!error && dev->type && dev->type->suspend) { - suspend_device_dbg(dev, state, "type "); - error = dev->type->suspend(dev, state); - suspend_report_result(dev->type->suspend, error); + if (dev->type) { + if (dev->type->pm) { + pm_dev_dbg(dev, state, "type "); + error = pm_op(dev, dev->type->pm, state); + } else if (dev->type->suspend) { + pm_dev_dbg(dev, state, "legacy type "); + error = dev->type->suspend(dev, state); + suspend_report_result(dev->type->suspend, error); + } + if (error) + goto End; } - if (!error && dev->bus && dev->bus->suspend) { - suspend_device_dbg(dev, state, ""); - error = dev->bus->suspend(dev, state); - suspend_report_result(dev->bus->suspend, error); + if (dev->bus) { + if (dev->bus->pm) { + pm_dev_dbg(dev, state, ""); + error = pm_op(dev, &dev->bus->pm->base, state); + } else if (dev->bus->suspend) { + pm_dev_dbg(dev, state, "legacy "); + error = dev->bus->suspend(dev, state); + suspend_report_result(dev->bus->suspend, error); + } } - + End: up(&dev->sem); return error; @@ -349,67 +648,141 @@ static int suspend_device(struct device *dev, pm_message_t state) /** * dpm_suspend - Suspend every device. - * @state: Power state to put each device in. + * @state: PM transition of the system being carried out. * - * Walk the dpm_locked list. Suspend each device and move it - * to the dpm_off list. - * - * (For historical reasons, if it returns -EAGAIN, that used to mean - * that the device would be called again with interrupts disabled. - * These days, we use the "suspend_late()" callback for that, so we - * print a warning and consider it an error). + * Execute the appropriate "suspend" callbacks for all devices. */ static int dpm_suspend(pm_message_t state) { + struct list_head list; int error = 0; + INIT_LIST_HEAD(&list); mutex_lock(&dpm_list_mtx); - while (!list_empty(&dpm_active)) { - struct list_head *entry = dpm_active.prev; - struct device *dev = to_device(entry); - - WARN_ON(dev->parent && dev->parent->power.sleeping); + while (!list_empty(&dpm_list)) { + struct device *dev = to_device(dpm_list.prev); - dev->power.sleeping = true; + get_device(dev); mutex_unlock(&dpm_list_mtx); + error = suspend_device(dev, state); + mutex_lock(&dpm_list_mtx); if (error) { - printk(KERN_ERR "Could not suspend device %s: " - "error %d%s\n", - kobject_name(&dev->kobj), - error, - (error == -EAGAIN ? - " (please convert to suspend_late)" : - "")); - dev->power.sleeping = false; + pm_dev_err(dev, state, "", error); + put_device(dev); break; } + dev->power.status = DPM_OFF; if (!list_empty(&dev->power.entry)) - list_move(&dev->power.entry, &dpm_off); + list_move(&dev->power.entry, &list); + put_device(dev); } - if (!error) - all_sleeping = true; + list_splice(&list, dpm_list.prev); mutex_unlock(&dpm_list_mtx); + return error; +} + +/** + * prepare_device - Execute the ->prepare() callback(s) for given device. + * @dev: Device. + * @state: PM transition of the system being carried out. + */ +static int prepare_device(struct device *dev, pm_message_t state) +{ + int error = 0; + + down(&dev->sem); + + if (dev->bus && dev->bus->pm && dev->bus->pm->base.prepare) { + pm_dev_dbg(dev, state, "preparing "); + error = dev->bus->pm->base.prepare(dev); + suspend_report_result(dev->bus->pm->base.prepare, error); + if (error) + goto End; + } + + if (dev->type && dev->type->pm && dev->type->pm->prepare) { + pm_dev_dbg(dev, state, "preparing type "); + error = dev->type->pm->prepare(dev); + suspend_report_result(dev->type->pm->prepare, error); + if (error) + goto End; + } + + if (dev->class && dev->class->pm && dev->class->pm->prepare) { + pm_dev_dbg(dev, state, "preparing class "); + error = dev->class->pm->prepare(dev); + suspend_report_result(dev->class->pm->prepare, error); + } + End: + up(&dev->sem); + + return error; +} +/** + * dpm_prepare - Prepare all devices for a PM transition. + * @state: PM transition of the system being carried out. + * + * Execute the ->prepare() callback for all devices. + */ +static int dpm_prepare(pm_message_t state) +{ + struct list_head list; + int error = 0; + + INIT_LIST_HEAD(&list); + mutex_lock(&dpm_list_mtx); + transition_started = true; + while (!list_empty(&dpm_list)) { + struct device *dev = to_device(dpm_list.next); + + get_device(dev); + dev->power.status = DPM_PREPARING; + mutex_unlock(&dpm_list_mtx); + + error = prepare_device(dev, state); + + mutex_lock(&dpm_list_mtx); + if (error) { + dev->power.status = DPM_ON; + if (error == -EAGAIN) { + put_device(dev); + continue; + } + printk(KERN_ERR "PM: Failed to prepare device %s " + "for power transition: error %d\n", + kobject_name(&dev->kobj), error); + put_device(dev); + break; + } + dev->power.status = DPM_SUSPENDING; + if (!list_empty(&dev->power.entry)) + list_move_tail(&dev->power.entry, &list); + put_device(dev); + } + list_splice(&list, &dpm_list); + mutex_unlock(&dpm_list_mtx); return error; } /** * device_suspend - Save state and stop all devices in system. - * @state: new power management state + * @state: PM transition of the system being carried out. * - * Prevent new devices from being registered, then lock all devices - * and suspend them. + * Prepare and suspend all devices. */ int device_suspend(pm_message_t state) { int error; might_sleep(); - error = dpm_suspend(state); + error = dpm_prepare(state); + if (!error) + error = dpm_suspend(state); if (error) - device_resume(); + device_resume(resume_event(state)); return error; } EXPORT_SYMBOL_GPL(device_suspend); -- cgit v1.2.3-70-g09d2 From d8f3de0d2412bb91639cfefc5b3c79dbf3812212 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 12 Jun 2008 23:24:06 +0200 Subject: Suspend-related patches for 2.6.27 ACPI PM: Add possibility to change suspend sequence There are some systems out there that don't work correctly with our current suspend/hibernation code ordering. Provide a workaround for these systems allowing them to pass 'acpi_sleep=old_ordering' in the kernel command line so that it will use the pre-ACPI 2.0 ("old") suspend code ordering. Unfortunately, this requires us to add a platform hook to the resuming of devices for recovering the platform in case one of the device drivers' .suspend() routines returns error code. Namely, ACPI 1.0 specifies that _PTS should be called before suspending devices, but _WAK still should be called before resuming them in order to undo the changes made by _PTS. However, if there is an error during suspending devices, they are automatically resumed without returning control to the PM core, so the _WAK has to be called from within device_resume() in that cases. The patch also reorders and refactors the ACPI suspend/hibernation code to avoid duplication as far as reasonably possible. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 6 +- arch/x86/kernel/acpi/sleep.c | 2 + drivers/acpi/sleep/main.c | 276 +++++++++++++++++++++--------------- drivers/base/power/main.c | 2 - include/linux/acpi.h | 3 + include/linux/suspend.h | 14 +- kernel/power/disk.c | 28 +++- kernel/power/main.c | 10 +- 8 files changed, 215 insertions(+), 126 deletions(-) (limited to 'drivers/base/power/main.c') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 9cf7b34f2db..18d793ea0dd 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -147,10 +147,14 @@ and is between 256 and 4096 characters. It is defined in the file default: 0 acpi_sleep= [HW,ACPI] Sleep options - Format: { s3_bios, s3_mode, s3_beep } + Format: { s3_bios, s3_mode, s3_beep, old_ordering } See Documentation/power/video.txt for s3_bios and s3_mode. s3_beep is for debugging; it makes the PC's speaker beep as soon as the kernel's real-mode entry point is called. + old_ordering causes the ACPI 1.0 ordering of the _PTS + control method, wrt putting devices into low power + states, to be enforced (the ACPI 2.0 ordering of _PTS is + used by default). acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode Format: { level | edge | high | low } diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index afc25ee9964..882e970032d 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -124,6 +124,8 @@ static int __init acpi_sleep_setup(char *str) acpi_realmode_flags |= 2; if (strncmp(str, "s3_beep", 7) == 0) acpi_realmode_flags |= 4; + if (strncmp(str, "old_ordering", 12) == 0) + acpi_old_suspend_ordering(); str = strchr(str, ','); if (str != NULL) str += strspn(str, ", \t"); diff --git a/drivers/acpi/sleep/main.c b/drivers/acpi/sleep/main.c index 0f2caea2fc8..4addf8ad50a 100644 --- a/drivers/acpi/sleep/main.c +++ b/drivers/acpi/sleep/main.c @@ -24,10 +24,6 @@ u8 sleep_states[ACPI_S_STATE_COUNT]; -#ifdef CONFIG_PM_SLEEP -static u32 acpi_target_sleep_state = ACPI_STATE_S0; -#endif - static int acpi_sleep_prepare(u32 acpi_state) { #ifdef CONFIG_ACPI_SLEEP @@ -50,9 +46,96 @@ static int acpi_sleep_prepare(u32 acpi_state) return 0; } -#ifdef CONFIG_SUSPEND -static struct platform_suspend_ops acpi_suspend_ops; +#ifdef CONFIG_PM_SLEEP +static u32 acpi_target_sleep_state = ACPI_STATE_S0; + +/* + * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the + * user to request that behavior by using the 'acpi_old_suspend_ordering' + * kernel command line option that causes the following variable to be set. + */ +static bool old_suspend_ordering; + +void __init acpi_old_suspend_ordering(void) +{ + old_suspend_ordering = true; +} + +/** + * acpi_pm_disable_gpes - Disable the GPEs. + */ +static int acpi_pm_disable_gpes(void) +{ + acpi_hw_disable_all_gpes(); + return 0; +} + +/** + * __acpi_pm_prepare - Prepare the platform to enter the target state. + * + * If necessary, set the firmware waking vector and do arch-specific + * nastiness to get the wakeup code to the waking vector. + */ +static int __acpi_pm_prepare(void) +{ + int error = acpi_sleep_prepare(acpi_target_sleep_state); + + if (error) + acpi_target_sleep_state = ACPI_STATE_S0; + return error; +} + +/** + * acpi_pm_prepare - Prepare the platform to enter the target sleep + * state and disable the GPEs. + */ +static int acpi_pm_prepare(void) +{ + int error = __acpi_pm_prepare(); + + if (!error) + acpi_hw_disable_all_gpes(); + return error; +} + +/** + * acpi_pm_finish - Instruct the platform to leave a sleep state. + * + * This is called after we wake back up (or if entering the sleep state + * failed). + */ +static void acpi_pm_finish(void) +{ + u32 acpi_state = acpi_target_sleep_state; + + if (acpi_state == ACPI_STATE_S0) + return; + printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n", + acpi_state); + acpi_disable_wakeup_device(acpi_state); + acpi_leave_sleep_state(acpi_state); + + /* reset firmware waking vector */ + acpi_set_firmware_waking_vector((acpi_physical_address) 0); + + acpi_target_sleep_state = ACPI_STATE_S0; +} + +/** + * acpi_pm_end - Finish up suspend sequence. + */ +static void acpi_pm_end(void) +{ + /* + * This is necessary in case acpi_pm_finish() is not called during a + * failing transition to a sleep state. + */ + acpi_target_sleep_state = ACPI_STATE_S0; +} +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_SUSPEND extern void do_suspend_lowlevel(void); static u32 acpi_suspend_states[] = { @@ -66,7 +149,6 @@ static u32 acpi_suspend_states[] = { * acpi_suspend_begin - Set the target system sleep state to the state * associated with given @pm_state, if supported. */ - static int acpi_suspend_begin(suspend_state_t pm_state) { u32 acpi_state = acpi_suspend_states[pm_state]; @@ -82,25 +164,6 @@ static int acpi_suspend_begin(suspend_state_t pm_state) return error; } -/** - * acpi_suspend_prepare - Do preliminary suspend work. - * - * If necessary, set the firmware waking vector and do arch-specific - * nastiness to get the wakeup code to the waking vector. - */ - -static int acpi_suspend_prepare(void) -{ - int error = acpi_sleep_prepare(acpi_target_sleep_state); - - if (error) { - acpi_target_sleep_state = ACPI_STATE_S0; - return error; - } - - return ACPI_SUCCESS(acpi_hw_disable_all_gpes()) ? 0 : -EFAULT; -} - /** * acpi_suspend_enter - Actually enter a sleep state. * @pm_state: ignored @@ -109,7 +172,6 @@ static int acpi_suspend_prepare(void) * assembly, which in turn call acpi_enter_sleep_state(). * It's unfortunate, but it works. Please fix if you're feeling frisky. */ - static int acpi_suspend_enter(suspend_state_t pm_state) { acpi_status status = AE_OK; @@ -166,39 +228,6 @@ static int acpi_suspend_enter(suspend_state_t pm_state) return ACPI_SUCCESS(status) ? 0 : -EFAULT; } -/** - * acpi_suspend_finish - Instruct the platform to leave a sleep state. - * - * This is called after we wake back up (or if entering the sleep state - * failed). - */ - -static void acpi_suspend_finish(void) -{ - u32 acpi_state = acpi_target_sleep_state; - - acpi_disable_wakeup_device(acpi_state); - acpi_leave_sleep_state(acpi_state); - - /* reset firmware waking vector */ - acpi_set_firmware_waking_vector((acpi_physical_address) 0); - - acpi_target_sleep_state = ACPI_STATE_S0; -} - -/** - * acpi_suspend_end - Finish up suspend sequence. - */ - -static void acpi_suspend_end(void) -{ - /* - * This is necessary in case acpi_suspend_finish() is not called during a - * failing transition to a sleep state. - */ - acpi_target_sleep_state = ACPI_STATE_S0; -} - static int acpi_suspend_state_valid(suspend_state_t pm_state) { u32 acpi_state; @@ -218,10 +247,39 @@ static int acpi_suspend_state_valid(suspend_state_t pm_state) static struct platform_suspend_ops acpi_suspend_ops = { .valid = acpi_suspend_state_valid, .begin = acpi_suspend_begin, - .prepare = acpi_suspend_prepare, + .prepare = acpi_pm_prepare, + .enter = acpi_suspend_enter, + .finish = acpi_pm_finish, + .end = acpi_pm_end, +}; + +/** + * acpi_suspend_begin_old - Set the target system sleep state to the + * state associated with given @pm_state, if supported, and + * execute the _PTS control method. This function is used if the + * pre-ACPI 2.0 suspend ordering has been requested. + */ +static int acpi_suspend_begin_old(suspend_state_t pm_state) +{ + int error = acpi_suspend_begin(pm_state); + + if (!error) + error = __acpi_pm_prepare(); + return error; +} + +/* + * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has + * been requested. + */ +static struct platform_suspend_ops acpi_suspend_ops_old = { + .valid = acpi_suspend_state_valid, + .begin = acpi_suspend_begin_old, + .prepare = acpi_pm_disable_gpes, .enter = acpi_suspend_enter, - .finish = acpi_suspend_finish, - .end = acpi_suspend_end, + .finish = acpi_pm_finish, + .end = acpi_pm_end, + .recover = acpi_pm_finish, }; #endif /* CONFIG_SUSPEND */ @@ -229,22 +287,9 @@ static struct platform_suspend_ops acpi_suspend_ops = { static int acpi_hibernation_begin(void) { acpi_target_sleep_state = ACPI_STATE_S4; - return 0; } -static int acpi_hibernation_prepare(void) -{ - int error = acpi_sleep_prepare(ACPI_STATE_S4); - - if (error) { - acpi_target_sleep_state = ACPI_STATE_S0; - return error; - } - - return ACPI_SUCCESS(acpi_hw_disable_all_gpes()) ? 0 : -EFAULT; -} - static int acpi_hibernation_enter(void) { acpi_status status = AE_OK; @@ -274,52 +319,55 @@ static void acpi_hibernation_leave(void) acpi_leave_sleep_state_prep(ACPI_STATE_S4); } -static void acpi_hibernation_finish(void) +static void acpi_pm_enable_gpes(void) { - acpi_disable_wakeup_device(ACPI_STATE_S4); - acpi_leave_sleep_state(ACPI_STATE_S4); - - /* reset firmware waking vector */ - acpi_set_firmware_waking_vector((acpi_physical_address) 0); - - acpi_target_sleep_state = ACPI_STATE_S0; + acpi_hw_enable_all_runtime_gpes(); } -static void acpi_hibernation_end(void) -{ - /* - * This is necessary in case acpi_hibernation_finish() is not called - * during a failing transition to the sleep state. - */ - acpi_target_sleep_state = ACPI_STATE_S0; -} +static struct platform_hibernation_ops acpi_hibernation_ops = { + .begin = acpi_hibernation_begin, + .end = acpi_pm_end, + .pre_snapshot = acpi_pm_prepare, + .finish = acpi_pm_finish, + .prepare = acpi_pm_prepare, + .enter = acpi_hibernation_enter, + .leave = acpi_hibernation_leave, + .pre_restore = acpi_pm_disable_gpes, + .restore_cleanup = acpi_pm_enable_gpes, +}; -static int acpi_hibernation_pre_restore(void) +/** + * acpi_hibernation_begin_old - Set the target system sleep state to + * ACPI_STATE_S4 and execute the _PTS control method. This + * function is used if the pre-ACPI 2.0 suspend ordering has been + * requested. + */ +static int acpi_hibernation_begin_old(void) { - acpi_status status; - - status = acpi_hw_disable_all_gpes(); - - return ACPI_SUCCESS(status) ? 0 : -EFAULT; -} + int error = acpi_sleep_prepare(ACPI_STATE_S4); -static void acpi_hibernation_restore_cleanup(void) -{ - acpi_hw_enable_all_runtime_gpes(); + if (!error) + acpi_target_sleep_state = ACPI_STATE_S4; + return error; } -static struct platform_hibernation_ops acpi_hibernation_ops = { - .begin = acpi_hibernation_begin, - .end = acpi_hibernation_end, - .pre_snapshot = acpi_hibernation_prepare, - .finish = acpi_hibernation_finish, - .prepare = acpi_hibernation_prepare, +/* + * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has + * been requested. + */ +static struct platform_hibernation_ops acpi_hibernation_ops_old = { + .begin = acpi_hibernation_begin_old, + .end = acpi_pm_end, + .pre_snapshot = acpi_pm_disable_gpes, + .finish = acpi_pm_finish, + .prepare = acpi_pm_disable_gpes, .enter = acpi_hibernation_enter, .leave = acpi_hibernation_leave, - .pre_restore = acpi_hibernation_pre_restore, - .restore_cleanup = acpi_hibernation_restore_cleanup, + .pre_restore = acpi_pm_disable_gpes, + .restore_cleanup = acpi_pm_enable_gpes, + .recover = acpi_pm_finish, }; -#endif /* CONFIG_HIBERNATION */ +#endif /* CONFIG_HIBERNATION */ int acpi_suspend(u32 acpi_state) { @@ -461,13 +509,15 @@ int __init acpi_sleep_init(void) } } - suspend_set_ops(&acpi_suspend_ops); + suspend_set_ops(old_suspend_ordering ? + &acpi_suspend_ops_old : &acpi_suspend_ops); #endif #ifdef CONFIG_HIBERNATION status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b); if (ACPI_SUCCESS(status)) { - hibernation_set_ops(&acpi_hibernation_ops); + hibernation_set_ops(old_suspend_ordering ? + &acpi_hibernation_ops_old : &acpi_hibernation_ops); sleep_states[ACPI_STATE_S4] = 1; printk(" S4"); } diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index d571204aaff..3250c5257b7 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -781,8 +781,6 @@ int device_suspend(pm_message_t state) error = dpm_prepare(state); if (!error) error = dpm_suspend(state); - if (error) - device_resume(resume_event(state)); return error; } EXPORT_SYMBOL_GPL(device_suspend); diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 41f7ce7edd7..33adcf91ef4 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -234,6 +234,9 @@ int acpi_check_region(resource_size_t start, resource_size_t n, int acpi_check_mem_region(resource_size_t start, resource_size_t n, const char *name); +#ifdef CONFIG_PM_SLEEP +void __init acpi_old_suspend_ordering(void); +#endif /* CONFIG_PM_SLEEP */ #else /* CONFIG_ACPI */ static inline int early_acpi_boot_init(void) diff --git a/include/linux/suspend.h b/include/linux/suspend.h index a6977423baf..e8e69159af7 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -86,6 +86,11 @@ typedef int __bitwise suspend_state_t; * that implement @begin(), but platforms implementing @begin() should * also provide a @end() which cleans up transitions aborted before * @enter(). + * + * @recover: Recover the platform from a suspend failure. + * Called by the PM core if the suspending of devices fails. + * This callback is optional and should only be implemented by platforms + * which require special recovery actions in that situation. */ struct platform_suspend_ops { int (*valid)(suspend_state_t state); @@ -94,6 +99,7 @@ struct platform_suspend_ops { int (*enter)(suspend_state_t state); void (*finish)(void); void (*end)(void); + void (*recover)(void); }; #ifdef CONFIG_SUSPEND @@ -149,7 +155,7 @@ extern void mark_free_pages(struct zone *zone); * The methods in this structure allow a platform to carry out special * operations required by it during a hibernation transition. * - * All the methods below must be implemented. + * All the methods below, except for @recover(), must be implemented. * * @begin: Tell the platform driver that we're starting hibernation. * Called right after shrinking memory and before freezing devices. @@ -189,6 +195,11 @@ extern void mark_free_pages(struct zone *zone); * @restore_cleanup: Clean up after a failing image restoration. * Called right after the nonboot CPUs have been enabled and before * thawing devices (runs with IRQs on). + * + * @recover: Recover the platform from a failure to suspend devices. + * Called by the PM core if the suspending of devices during hibernation + * fails. This callback is optional and should only be implemented by + * platforms which require special recovery actions in that situation. */ struct platform_hibernation_ops { int (*begin)(void); @@ -200,6 +211,7 @@ struct platform_hibernation_ops { void (*leave)(void); int (*pre_restore)(void); void (*restore_cleanup)(void); + void (*recover)(void); }; #ifdef CONFIG_HIBERNATION diff --git a/kernel/power/disk.c b/kernel/power/disk.c index d416be0efa8..f011e0870b5 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -179,6 +179,17 @@ static void platform_restore_cleanup(int platform_mode) hibernation_ops->restore_cleanup(); } +/** + * platform_recover - recover the platform from a failure to suspend + * devices. + */ + +static void platform_recover(int platform_mode) +{ + if (platform_mode && hibernation_ops && hibernation_ops->recover) + hibernation_ops->recover(); +} + /** * create_image - freeze devices that need to be frozen with interrupts * off, create the hibernation image and thaw those devices. Control @@ -258,10 +269,10 @@ int hibernation_snapshot(int platform_mode) suspend_console(); error = device_suspend(PMSG_FREEZE); if (error) - goto Resume_console; + goto Recover_platform; if (hibernation_test(TEST_DEVICES)) - goto Resume_devices; + goto Recover_platform; error = platform_pre_snapshot(platform_mode); if (error || hibernation_test(TEST_PLATFORM)) @@ -285,11 +296,14 @@ int hibernation_snapshot(int platform_mode) Resume_devices: device_resume(in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); - Resume_console: resume_console(); Close: platform_end(platform_mode); return error; + + Recover_platform: + platform_recover(platform_mode); + goto Resume_devices; } /** @@ -398,8 +412,11 @@ int hibernation_platform_enter(void) suspend_console(); error = device_suspend(PMSG_HIBERNATE); - if (error) - goto Resume_console; + if (error) { + if (hibernation_ops->recover) + hibernation_ops->recover(); + goto Resume_devices; + } error = hibernation_ops->prepare(); if (error) @@ -428,7 +445,6 @@ int hibernation_platform_enter(void) hibernation_ops->finish(); Resume_devices: device_resume(PMSG_RESTORE); - Resume_console: resume_console(); Close: hibernation_ops->end(); diff --git a/kernel/power/main.c b/kernel/power/main.c index d023b6b584e..3398f4651aa 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -269,11 +269,11 @@ int suspend_devices_and_enter(suspend_state_t state) error = device_suspend(PMSG_SUSPEND); if (error) { printk(KERN_ERR "PM: Some devices failed to suspend\n"); - goto Resume_console; + goto Recover_platform; } if (suspend_test(TEST_DEVICES)) - goto Resume_devices; + goto Recover_platform; if (suspend_ops->prepare) { error = suspend_ops->prepare(); @@ -294,12 +294,16 @@ int suspend_devices_and_enter(suspend_state_t state) suspend_ops->finish(); Resume_devices: device_resume(PMSG_RESUME); - Resume_console: resume_console(); Close: if (suspend_ops->end) suspend_ops->end(); return error; + + Recover_platform: + if (suspend_ops->recover) + suspend_ops->recover(); + goto Resume_devices; } /** -- cgit v1.2.3-70-g09d2