diff options
| -rw-r--r-- | arch/x86/kernel/apm_32.c | 8 | ||||
| -rw-r--r-- | drivers/base/power/main.c | 675 | ||||
| -rw-r--r-- | drivers/base/power/power.h | 2 | ||||
| -rw-r--r-- | drivers/base/power/trace.c | 4 | ||||
| -rw-r--r-- | include/linux/device.h | 9 | ||||
| -rw-r--r-- | include/linux/pm.h | 314 | ||||
| -rw-r--r-- | kernel/power/disk.c | 22 | ||||
| -rw-r--r-- | kernel/power/main.c | 6 |
8 files changed, 845 insertions, 195 deletions
diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c index bf9290e..c1735f6 100644 --- a/arch/x86/kernel/apm_32.c +++ b/arch/x86/kernel/apm_32.c @@ -1211,9 +1211,9 @@ static int suspend(int vetoable) if (err != APM_SUCCESS) apm_error("suspend", err); err = (err == APM_SUCCESS) ? 0 : -EIO; - device_power_up(); + device_power_up(PMSG_RESUME); local_irq_enable(); - device_resume(); + device_resume(PMSG_RESUME); queue_event(APM_NORMAL_RESUME, NULL); spin_lock(&user_list_lock); for (as = user_list; as != NULL; as = as->next) { @@ -1238,7 +1238,7 @@ static void standby(void) apm_error("standby", err); local_irq_disable(); - device_power_up(); + device_power_up(PMSG_RESUME); local_irq_enable(); } @@ -1324,7 +1324,7 @@ static void check_events(void) ignore_bounce = 1; if ((event != APM_NORMAL_RESUME) || (ignore_normal_resume == 0)) { - device_resume(); + device_resume(PMSG_RESUME); queue_event(event, NULL); } ignore_normal_resume = 0; diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 45cc3d9..d571204 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 <linux/device.h> @@ -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); diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h index a6894f2..a3252c0 100644 --- a/drivers/base/power/power.h +++ b/drivers/base/power/power.h @@ -4,7 +4,7 @@ * main.c */ -extern struct list_head dpm_active; /* The active device list */ +extern struct list_head dpm_list; /* The active device list */ static inline struct device *to_device(struct list_head *entry) { diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c index 2b4b392..8c1e656 100644 --- a/drivers/base/power/trace.c +++ b/drivers/base/power/trace.c @@ -188,9 +188,9 @@ static int show_file_hash(unsigned int value) static int show_dev_hash(unsigned int value) { int match = 0; - struct list_head * entry = dpm_active.prev; + struct list_head *entry = dpm_list.prev; - while (entry != &dpm_active) { + while (entry != &dpm_list) { struct device * dev = to_device(entry); unsigned int hash = hash_string(DEVSEED, dev->bus_id, DEVHASH); if (hash == value) { diff --git a/include/linux/device.h b/include/linux/device.h index 6a2d04c..f71a78d 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -68,6 +68,8 @@ struct bus_type { int (*resume_early)(struct device *dev); int (*resume)(struct device *dev); + struct pm_ext_ops *pm; + struct bus_type_private *p; }; @@ -131,6 +133,8 @@ struct device_driver { int (*resume) (struct device *dev); struct attribute_group **groups; + struct pm_ops *pm; + struct driver_private *p; }; @@ -197,6 +201,8 @@ struct class { int (*suspend)(struct device *dev, pm_message_t state); int (*resume)(struct device *dev); + + struct pm_ops *pm; }; extern int __must_check class_register(struct class *class); @@ -248,8 +254,11 @@ struct device_type { struct attribute_group **groups; int (*uevent)(struct device *dev, struct kobj_uevent_env *env); void (*release)(struct device *dev); + int (*suspend)(struct device *dev, pm_message_t state); int (*resume)(struct device *dev); + + struct pm_ops *pm; }; /* interface for exporting device attributes */ diff --git a/include/linux/pm.h b/include/linux/pm.h index 39a7ee8..4ad9de9 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -112,7 +112,9 @@ typedef struct pm_message { int event; } pm_message_t; -/* +/** + * struct pm_ops - device PM callbacks + * * Several driver power state transitions are externally visible, affecting * the state of pending I/O queues and (for drivers that touch hardware) * interrupts, wakeups, DMA, and other hardware state. There may also be @@ -120,6 +122,284 @@ typedef struct pm_message { * to the rest of the driver stack (such as a driver that's ON gating off * clocks which are not in active use). * + * The externally visible transitions are handled with the help of the following + * callbacks included in this structure: + * + * @prepare: Prepare the device for the upcoming transition, but do NOT change + * its hardware state. Prevent new children of the device from being + * registered after @prepare() returns (the driver's subsystem and + * generally the rest of the kernel is supposed to prevent new calls to the + * probe method from being made too once @prepare() has succeeded). If + * @prepare() detects a situation it cannot handle (e.g. registration of a + * child already in progress), it may return -EAGAIN, so that the PM core + * can execute it once again (e.g. after the new child has been registered) + * to recover from the race condition. This method is executed for all + * kinds of suspend transitions and is followed by one of the suspend + * callbacks: @suspend(), @freeze(), or @poweroff(). + * The PM core executes @prepare() for all devices before starting to + * execute suspend callbacks for any of them, so drivers may assume all of + * the other devices to be present and functional while @prepare() is being + * executed. In particular, it is safe to make GFP_KERNEL memory + * allocations from within @prepare(). However, drivers may NOT assume + * anything about the availability of the user space at that time and it + * is not correct to request firmware from within @prepare() (it's too + * late to do that). [To work around this limitation, drivers may + * register suspend and hibernation notifiers that are executed before the + * freezing of tasks.] + * + * @complete: Undo the changes made by @prepare(). This method is executed for + * all kinds of resume transitions, following one of the resume callbacks: + * @resume(), @thaw(), @restore(). Also called if the state transition + * fails before the driver's suspend callback (@suspend(), @freeze(), + * @poweroff()) can be executed (e.g. if the suspend callback fails for one + * of the other devices that the PM core has unsuccessfully attempted to + * suspend earlier). + * The PM core executes @complete() after it has executed the appropriate + * resume callback for all devices. + * + * @suspend: Executed before putting the system into a sleep state in which the + * contents of main memory are preserved. Quiesce the device, put it into + * a low power state appropriate for the upcoming system state (such as + * PCI_D3hot), and enable wakeup events as appropriate. + * + * @resume: Executed after waking the system up from a sleep state in which the + * contents of main memory were preserved. Put the device into the + * appropriate state, according to the information saved in memory by the + * preceding @suspend(). The driver starts working again, responding to + * hardware events and software requests. The hardware may have gone + * through a power-off reset, or it may have maintained state from the + * previous suspend() which the driver may rely on while resuming. On most + * platforms, there are no restrictions on availability of resources like + * clocks during @resume(). + * + * @freeze: Hibernation-specific, executed before creating a hibernation image. + * Quiesce operations so that a consistent image can be created, but do NOT + * otherwise put the device into a low power device state and do NOT emit + * system wakeup events. Save in main memory the device settings to be + * used by @restore() during the subsequent resume from hibernation or by + * the subsequent @thaw(), if the creation of the image or the restoration + * of main memory contents from it fails. + * + * @thaw: Hibernation-specific, executed after creating a hibernation image OR + * if the creation of the image fails. Also executed after a failing + * attempt to restore the contents of main memory from such an image. + * Undo the changes made by the preceding @freeze(), so the device can be + * operated in the same way as immediately before the call to @freeze(). + * + * @poweroff: Hibernation-specific, executed after saving a hibernation image. + * Quiesce the device, put it into a low power state appropriate for the + * upcoming system state (such as PCI_D3hot), and enable wakeup events as + * appropriate. + * + * @restore: Hibernation-specific, executed after restoring the contents of main + * memory from a hibernation image. Driver starts working again, + * responding to hardware events and software requests. Drivers may NOT + * make ANY assumptions about the hardware state right prior to @restore(). + * On most platforms, there are no restrictions on availability of + * resources like clocks during @restore(). + * + * All of the above callbacks, except for @complete(), return error codes. + * However, the error codes returned by the resume operations, @resume(), + * @thaw(), and @restore(), do not cause the PM core to abort the resume + * transition during which they are returned. The error codes returned in + * that cases are only printed by the PM core to the system logs for debugging + * purposes. Still, it is recommended that drivers only return error codes + * from their resume methods in case of an unrecoverable failure (i.e. when the + * device being handled refuses to resume and becomes unusable) to allow us to + * modify the PM core in the future, so that it can avoid attempting to handle + * devices that failed to resume and their children. + * + * It is allowed to unregister devices while the above callbacks are being + * executed. However, it is not allowed to unregister a device from within any + * of its own callbacks. + */ + +struct pm_ops { + int (*prepare)(struct device *dev); + void (*complete)(struct device *dev); + int (*suspend)(struct device *dev); + int (*resume)(struct device *dev); + int (*freeze)(struct device *dev); + int (*thaw)(struct device *dev); + int (*poweroff)(struct device *dev); + int (*restore)(struct device *dev); +}; + +/** + * struct pm_ext_ops - extended device PM callbacks + * + * Some devices require certain operations related to suspend and hibernation + * to be carried out with interrupts disabled. Thus, 'struct pm_ext_ops' below + * is defined, adding callbacks to be executed with interrupts disabled to + * 'struct pm_ops'. + * + * The following callbacks included in 'struct pm_ext_ops' are executed with + * the nonboot CPUs switched off and with interrupts disabled on the only + * functional CPU. They also are executed with the PM core list of devices + * locked, so they must NOT unregister any devices. + * + * @suspend_noirq: Complete the operations of ->suspend() by carrying out any + * actions required for suspending the device that need interrupts to be + * disabled + * + * @resume_noirq: Prepare for the execution of ->resume() by carrying out any + * actions required for resuming the device that need interrupts to be + * disabled + * + * @freeze_noirq: Complete the operations of ->freeze() by carrying out any + * actions required for freezing the device that need interrupts to be + * disabled + * + * @thaw_noirq: Prepare for the execution of ->thaw() by carrying out any + * actions required for thawing the device that need interrupts to be + * disabled + * + * @poweroff_noirq: Complete the operations of ->poweroff() by carrying out any + * actions required for handling the device that need interrupts to be + * disabled + * + * @restore_noirq: Prepare for the execution of ->restore() by carrying out any + * actions required for restoring the operations of the device that need + * interrupts to be disabled + * + * All of the above callbacks return error codes, but the error codes returned + * by the resume operations, @resume_noirq(), @thaw_noirq(), and + * @restore_noirq(), do not cause the PM core to abort the resume transition + * during which they are returned. The error codes returned in that cases are + * only printed by the PM core to the system logs for debugging purposes. + * Still, as stated above, it is recommended that drivers only return error + * codes from their resume methods if the device being handled fails to resume + * and is not usable any more. + */ + +struct pm_ext_ops { + struct pm_ops base; + int (*suspend_noirq)(struct device *dev); + int (*resume_noirq)(struct device *dev); + int (*freeze_noirq)(struct device *dev); + int (*thaw_noirq)(struct device *dev); + int (*poweroff_noirq)(struct device *dev); + int (*restore_noirq)(struct device *dev); +}; + +/** + * PM_EVENT_ messages + * + * The following PM_EVENT_ messages are defined for the internal use of the PM + * core, in order to provide a mechanism allowing the high level suspend and + * hibernation code to convey the necessary information to the device PM core + * code: + * + * ON No transition. + * + * FREEZE System is going to hibernate, call ->prepare() and ->freeze() + * for all devices. + * + * SUSPEND System is going to suspend, call ->prepare() and ->suspend() + * for all devices. + * + * HIBERNATE Hibernation image has been saved, call ->prepare() and + * ->poweroff() for all devices. + * + * QUIESCE Contents of main memory are going to be restored from a (loaded) + * hibernation image, call ->prepare() and ->freeze() for all + * devices. + * + * RESUME System is resuming, call ->resume() and ->complete() for all + * devices. + * + * THAW Hibernation image has been created, call ->thaw() and + * ->complete() for all devices. + * + * RESTORE Contents of main memory have been restored from a hibernation + * image, call ->restore() and ->complete() for all devices. + * + * RECOVER Creation of a hibernation image or restoration of the main + * memory contents from a hibernation image has failed, call + * ->thaw() and ->complete() for all devices. + */ + +#define PM_EVENT_ON 0x0000 +#define PM_EVENT_FREEZE 0x0001 +#define PM_EVENT_SUSPEND 0x0002 +#define PM_EVENT_HIBERNATE 0x0004 +#define PM_EVENT_QUIESCE 0x0008 +#define PM_EVENT_RESUME 0x0010 +#define PM_EVENT_THAW 0x0020 +#define PM_EVENT_RESTORE 0x0040 +#define PM_EVENT_RECOVER 0x0080 + +#define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE) + +#define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, }) +#define PMSG_QUIESCE ((struct pm_message){ .event = PM_EVENT_QUIESCE, }) +#define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, }) +#define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, }) +#define PMSG_RESUME ((struct pm_message){ .event = PM_EVENT_RESUME, }) +#define PMSG_THAW ((struct pm_message){ .event = PM_EVENT_THAW, }) +#define PMSG_RESTORE ((struct pm_message){ .event = PM_EVENT_RESTORE, }) +#define PMSG_RECOVER ((struct pm_message){ .event = PM_EVENT_RECOVER, }) +#define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, }) + +/** + * Device power management states + * + * These state labels are used internally by the PM core to indicate the current + * status of a device with respect to the PM core operations. + * + * DPM_ON Device is regarded as operational. Set this way + * initially and when ->complete() is about to be called. + * Also set when ->prepare() fails. + * + * DPM_PREPARING Device is going to be prepared for a PM transition. Set + * when ->prepare() is about to be called. + * + * DPM_RESUMING Device is going to be resumed. Set when ->resume(), + * ->thaw(), or ->restore() is about to be called. + * + * DPM_SUSPENDING Device has been prepared for a power transition. Set + * when ->prepare() has just succeeded. + * + * DPM_OFF Device is regarded as inactive. Set immediately after + * ->suspend(), ->freeze(), or ->poweroff() has succeeded. + * Also set when ->resume()_noirq, ->thaw_noirq(), or + * ->restore_noirq() is about to be called. + * + * DPM_OFF_IRQ Device is in a "deep sleep". Set immediately after + * ->suspend_noirq(), ->freeze_noirq(), or + * ->poweroff_noirq() has just succeeded. + */ + +enum dpm_state { + DPM_INVALID, + DPM_ON, + DPM_PREPARING, + DPM_RESUMING, + DPM_SUSPENDING, + DPM_OFF, + DPM_OFF_IRQ, +}; + +struct dev_pm_info { + pm_message_t power_state; + unsigned can_wakeup:1; + unsigned should_wakeup:1; + enum dpm_state status; /* Owned by the PM core */ +#ifdef CONFIG_PM_SLEEP + struct list_head entry; +#endif +}; + +/* + * The PM_EVENT_ messages are also used by drivers implementing the legacy + * suspend framework, based on the ->suspend() and ->resume() callbacks common + * for suspend and hibernation transitions, according to the rules below. + */ + +/* Necessary, because several drivers use PM_EVENT_PRETHAW */ +#define PM_EVENT_PRETHAW PM_EVENT_QUIESCE + +/* * One transition is triggered by resume(), after a suspend() call; the * message is implicit: * @@ -164,35 +444,13 @@ typedef struct pm_message { * or from system low-power states such as standby or suspend-to-RAM. */ -#define PM_EVENT_ON 0 -#define PM_EVENT_FREEZE 1 -#define PM_EVENT_SUSPEND 2 -#define PM_EVENT_HIBERNATE 4 -#define PM_EVENT_PRETHAW 8 - -#define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE) - -#define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, }) -#define PMSG_PRETHAW ((struct pm_message){ .event = PM_EVENT_PRETHAW, }) -#define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, }) -#define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, }) -#define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, }) - -struct dev_pm_info { - pm_message_t power_state; - unsigned can_wakeup:1; - unsigned should_wakeup:1; - bool sleeping:1; /* Owned by the PM core */ -#ifdef CONFIG_PM_SLEEP - struct list_head entry; -#endif -}; +#ifdef CONFIG_PM_SLEEP +extern void device_pm_lock(void); +extern void device_power_up(pm_message_t state); +extern void device_resume(pm_message_t state); +extern void device_pm_unlock(void); extern int device_power_down(pm_message_t state); -extern void device_power_up(void); -extern void device_resume(void); - -#ifdef CONFIG_PM_SLEEP extern int device_suspend(pm_message_t state); extern int device_prepare_suspend(pm_message_t state); diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 14a656c..d416be0 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -193,6 +193,7 @@ static int create_image(int platform_mode) if (error) return error; + device_pm_lock(); local_irq_disable(); /* At this point, device_suspend() has been called, but *not* * device_power_down(). We *must* call device_power_down() now. @@ -224,9 +225,11 @@ static int create_image(int platform_mode) /* NOTE: device_power_up() is just a resume() for devices * that suspended with irqs off ... no overall powerup. */ - device_power_up(); + device_power_up(in_suspend ? + (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); Enable_irqs: local_irq_enable(); + device_pm_unlock(); return error; } @@ -280,7 +283,8 @@ int hibernation_snapshot(int platform_mode) Finish: platform_finish(platform_mode); Resume_devices: - device_resume(); + device_resume(in_suspend ? + (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); Resume_console: resume_console(); Close: @@ -300,8 +304,9 @@ static int resume_target_kernel(void) { int error; + device_pm_lock(); local_irq_disable(); - error = device_power_down(PMSG_PRETHAW); + error = device_power_down(PMSG_QUIESCE); if (error) { printk(KERN_ERR "PM: Some devices failed to power down, " "aborting resume\n"); @@ -329,9 +334,10 @@ static int resume_target_kernel(void) swsusp_free(); restore_processor_state(); touch_softlockup_watchdog(); - device_power_up(); + device_power_up(PMSG_RECOVER); Enable_irqs: local_irq_enable(); + device_pm_unlock(); return error; } @@ -350,7 +356,7 @@ int hibernation_restore(int platform_mode) pm_prepare_console(); suspend_console(); - error = device_suspend(PMSG_PRETHAW); + error = device_suspend(PMSG_QUIESCE); if (error) goto Finish; @@ -362,7 +368,7 @@ int hibernation_restore(int platform_mode) enable_nonboot_cpus(); } platform_restore_cleanup(platform_mode); - device_resume(); + device_resume(PMSG_RECOVER); Finish: resume_console(); pm_restore_console(); @@ -403,6 +409,7 @@ int hibernation_platform_enter(void) if (error) goto Finish; + device_pm_lock(); local_irq_disable(); error = device_power_down(PMSG_HIBERNATE); if (!error) { @@ -411,6 +418,7 @@ int hibernation_platform_enter(void) while (1); } local_irq_enable(); + device_pm_unlock(); /* * We don't need to reenable the nonboot CPUs or resume consoles, since @@ -419,7 +427,7 @@ int hibernation_platform_enter(void) Finish: hibernation_ops->finish(); Resume_devices: - device_resume(); + device_resume(PMSG_RESTORE); Resume_console: resume_console(); Close: diff --git a/kernel/power/main.c b/kernel/power/main.c index 6a6d5eb..d023b6b 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -228,6 +228,7 @@ static int suspend_enter(suspend_state_t state) { int error = 0; + device_pm_lock(); arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); @@ -239,10 +240,11 @@ static int suspend_enter(suspend_state_t state) if (!suspend_test(TEST_CORE)) error = suspend_ops->enter(state); - device_power_up(); + device_power_up(PMSG_RESUME); Done: arch_suspend_enable_irqs(); BUG_ON(irqs_disabled()); + device_pm_unlock(); return error; } @@ -291,7 +293,7 @@ int suspend_devices_and_enter(suspend_state_t state) if (suspend_ops->finish) suspend_ops->finish(); Resume_devices: - device_resume(); + device_resume(PMSG_RESUME); Resume_console: resume_console(); Close: |
