diff options
Diffstat (limited to 'drivers/base/power/wakeup.c')
| -rw-r--r-- | drivers/base/power/wakeup.c | 1214 |
1 files changed, 1214 insertions, 0 deletions
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c new file mode 100644 index 000000000..8997e0227 --- /dev/null +++ b/drivers/base/power/wakeup.c @@ -0,0 +1,1214 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/wakeup.c - System wakeup events framework + * + * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. + */ +#define pr_fmt(fmt) "PM: " fmt + +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/sched/signal.h> +#include <linux/capability.h> +#include <linux/export.h> +#include <linux/suspend.h> +#include <linux/seq_file.h> +#include <linux/debugfs.h> +#include <linux/pm_wakeirq.h> +#include <trace/events/power.h> + +#include "power.h" + +#ifndef CONFIG_SUSPEND +suspend_state_t pm_suspend_target_state; +#define pm_suspend_target_state (PM_SUSPEND_ON) +#endif + +#define list_for_each_entry_rcu_locked(pos, head, member) \ + list_for_each_entry_rcu(pos, head, member, \ + srcu_read_lock_held(&wakeup_srcu)) +/* + * If set, the suspend/hibernate code will abort transitions to a sleep state + * if wakeup events are registered during or immediately before the transition. + */ +bool events_check_enabled __read_mostly; + +/* First wakeup IRQ seen by the kernel in the last cycle. */ +static unsigned int wakeup_irq[2] __read_mostly; +static DEFINE_RAW_SPINLOCK(wakeup_irq_lock); + +/* If greater than 0 and the system is suspending, terminate the suspend. */ +static atomic_t pm_abort_suspend __read_mostly; + +/* + * Combined counters of registered wakeup events and wakeup events in progress. + * They need to be modified together atomically, so it's better to use one + * atomic variable to hold them both. + */ +static atomic_t combined_event_count = ATOMIC_INIT(0); + +#define IN_PROGRESS_BITS (sizeof(int) * 4) +#define MAX_IN_PROGRESS ((1 << IN_PROGRESS_BITS) - 1) + +static void split_counters(unsigned int *cnt, unsigned int *inpr) +{ + unsigned int comb = atomic_read(&combined_event_count); + + *cnt = (comb >> IN_PROGRESS_BITS); + *inpr = comb & MAX_IN_PROGRESS; +} + +/* A preserved old value of the events counter. */ +static unsigned int saved_count; + +static DEFINE_RAW_SPINLOCK(events_lock); + +static void pm_wakeup_timer_fn(struct timer_list *t); + +static LIST_HEAD(wakeup_sources); + +static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue); + +DEFINE_STATIC_SRCU(wakeup_srcu); + +static struct wakeup_source deleted_ws = { + .name = "deleted", + .lock = __SPIN_LOCK_UNLOCKED(deleted_ws.lock), +}; + +static DEFINE_IDA(wakeup_ida); + +/** + * wakeup_source_create - Create a struct wakeup_source object. + * @name: Name of the new wakeup source. + */ +struct wakeup_source *wakeup_source_create(const char *name) +{ + struct wakeup_source *ws; + const char *ws_name; + int id; + + ws = kzalloc(sizeof(*ws), GFP_KERNEL); + if (!ws) + goto err_ws; + + ws_name = kstrdup_const(name, GFP_KERNEL); + if (!ws_name) + goto err_name; + ws->name = ws_name; + + id = ida_alloc(&wakeup_ida, GFP_KERNEL); + if (id < 0) + goto err_id; + ws->id = id; + + return ws; + +err_id: + kfree_const(ws->name); +err_name: + kfree(ws); +err_ws: + return NULL; +} +EXPORT_SYMBOL_GPL(wakeup_source_create); + +/* + * Record wakeup_source statistics being deleted into a dummy wakeup_source. + */ +static void wakeup_source_record(struct wakeup_source *ws) +{ + unsigned long flags; + + spin_lock_irqsave(&deleted_ws.lock, flags); + + if (ws->event_count) { + deleted_ws.total_time = + ktime_add(deleted_ws.total_time, ws->total_time); + deleted_ws.prevent_sleep_time = + ktime_add(deleted_ws.prevent_sleep_time, + ws->prevent_sleep_time); + deleted_ws.max_time = + ktime_compare(deleted_ws.max_time, ws->max_time) > 0 ? + deleted_ws.max_time : ws->max_time; + deleted_ws.event_count += ws->event_count; + deleted_ws.active_count += ws->active_count; + deleted_ws.relax_count += ws->relax_count; + deleted_ws.expire_count += ws->expire_count; + deleted_ws.wakeup_count += ws->wakeup_count; + } + + spin_unlock_irqrestore(&deleted_ws.lock, flags); +} + +static void wakeup_source_free(struct wakeup_source *ws) +{ + ida_free(&wakeup_ida, ws->id); + kfree_const(ws->name); + kfree(ws); +} + +/** + * 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; + + __pm_relax(ws); + wakeup_source_record(ws); + wakeup_source_free(ws); +} +EXPORT_SYMBOL_GPL(wakeup_source_destroy); + +/** + * wakeup_source_add - Add given object to the list of wakeup sources. + * @ws: Wakeup source object to add to the list. + */ +void wakeup_source_add(struct wakeup_source *ws) +{ + unsigned long flags; + + if (WARN_ON(!ws)) + return; + + spin_lock_init(&ws->lock); + timer_setup(&ws->timer, pm_wakeup_timer_fn, 0); + ws->active = false; + + raw_spin_lock_irqsave(&events_lock, flags); + list_add_rcu(&ws->entry, &wakeup_sources); + raw_spin_unlock_irqrestore(&events_lock, flags); +} +EXPORT_SYMBOL_GPL(wakeup_source_add); + +/** + * wakeup_source_remove - Remove given object from the wakeup sources list. + * @ws: Wakeup source object to remove from the list. + */ +void wakeup_source_remove(struct wakeup_source *ws) +{ + unsigned long flags; + + if (WARN_ON(!ws)) + return; + + raw_spin_lock_irqsave(&events_lock, flags); + list_del_rcu(&ws->entry); + raw_spin_unlock_irqrestore(&events_lock, flags); + synchronize_srcu(&wakeup_srcu); + + del_timer_sync(&ws->timer); + /* + * Clear timer.function to make wakeup_source_not_registered() treat + * this wakeup source as not registered. + */ + ws->timer.function = NULL; +} +EXPORT_SYMBOL_GPL(wakeup_source_remove); + +/** + * wakeup_source_register - Create wakeup source and add it to the list. + * @dev: Device this wakeup source is associated with (or NULL if virtual). + * @name: Name of the wakeup source to register. + */ +struct wakeup_source *wakeup_source_register(struct device *dev, + const char *name) +{ + struct wakeup_source *ws; + int ret; + + ws = wakeup_source_create(name); + if (ws) { + if (!dev || device_is_registered(dev)) { + ret = wakeup_source_sysfs_add(dev, ws); + if (ret) { + wakeup_source_free(ws); + return NULL; + } + } + wakeup_source_add(ws); + } + return ws; +} +EXPORT_SYMBOL_GPL(wakeup_source_register); + +/** + * wakeup_source_unregister - Remove wakeup source from the list and remove it. + * @ws: Wakeup source object to unregister. + */ +void wakeup_source_unregister(struct wakeup_source *ws) +{ + if (ws) { + wakeup_source_remove(ws); + if (ws->dev) + wakeup_source_sysfs_remove(ws); + + wakeup_source_destroy(ws); + } +} +EXPORT_SYMBOL_GPL(wakeup_source_unregister); + +/** + * wakeup_sources_read_lock - Lock wakeup source list for read. + * + * Returns an index of srcu lock for struct wakeup_srcu. + * This index must be passed to the matching wakeup_sources_read_unlock(). + */ +int wakeup_sources_read_lock(void) +{ + return srcu_read_lock(&wakeup_srcu); +} +EXPORT_SYMBOL_GPL(wakeup_sources_read_lock); + +/** + * wakeup_sources_read_unlock - Unlock wakeup source list. + * @idx: return value from corresponding wakeup_sources_read_lock() + */ +void wakeup_sources_read_unlock(int idx) +{ + srcu_read_unlock(&wakeup_srcu, idx); +} +EXPORT_SYMBOL_GPL(wakeup_sources_read_unlock); + +/** + * wakeup_sources_walk_start - Begin a walk on wakeup source list + * + * Returns first object of the list of wakeup sources. + * + * Note that to be safe, wakeup sources list needs to be locked by calling + * wakeup_source_read_lock() for this. + */ +struct wakeup_source *wakeup_sources_walk_start(void) +{ + struct list_head *ws_head = &wakeup_sources; + + return list_entry_rcu(ws_head->next, struct wakeup_source, entry); +} +EXPORT_SYMBOL_GPL(wakeup_sources_walk_start); + +/** + * wakeup_sources_walk_next - Get next wakeup source from the list + * @ws: Previous wakeup source object + * + * Note that to be safe, wakeup sources list needs to be locked by calling + * wakeup_source_read_lock() for this. + */ +struct wakeup_source *wakeup_sources_walk_next(struct wakeup_source *ws) +{ + struct list_head *ws_head = &wakeup_sources; + + return list_next_or_null_rcu(ws_head, &ws->entry, + struct wakeup_source, entry); +} +EXPORT_SYMBOL_GPL(wakeup_sources_walk_next); + +/** + * device_wakeup_attach - Attach a wakeup source object to a device object. + * @dev: Device to handle. + * @ws: Wakeup source object to attach to @dev. + * + * This causes @dev to be treated as a wakeup device. + */ +static int device_wakeup_attach(struct device *dev, struct wakeup_source *ws) +{ + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + spin_unlock_irq(&dev->power.lock); + return -EEXIST; + } + dev->power.wakeup = ws; + if (dev->power.wakeirq) + device_wakeup_attach_irq(dev, dev->power.wakeirq); + spin_unlock_irq(&dev->power.lock); + return 0; +} + +/** + * device_wakeup_enable - Enable given device to be a wakeup source. + * @dev: Device to handle. + * + * Create a wakeup source object, register it and attach it to @dev. + */ +int device_wakeup_enable(struct device *dev) +{ + struct wakeup_source *ws; + int ret; + + if (!dev || !dev->power.can_wakeup) + return -EINVAL; + + if (pm_suspend_target_state != PM_SUSPEND_ON) + dev_dbg(dev, "Suspicious %s() during system transition!\n", __func__); + + ws = wakeup_source_register(dev, dev_name(dev)); + if (!ws) + return -ENOMEM; + + ret = device_wakeup_attach(dev, ws); + if (ret) + wakeup_source_unregister(ws); + + return ret; +} +EXPORT_SYMBOL_GPL(device_wakeup_enable); + +/** + * device_wakeup_attach_irq - Attach a wakeirq to a wakeup source + * @dev: Device to handle + * @wakeirq: Device specific wakeirq entry + * + * Attach a device wakeirq to the wakeup source so the device + * wake IRQ can be configured automatically for suspend and + * resume. + * + * Call under the device's power.lock lock. + */ +void device_wakeup_attach_irq(struct device *dev, + struct wake_irq *wakeirq) +{ + struct wakeup_source *ws; + + ws = dev->power.wakeup; + if (!ws) + return; + + if (ws->wakeirq) + dev_err(dev, "Leftover wakeup IRQ found, overriding\n"); + + ws->wakeirq = wakeirq; +} + +/** + * device_wakeup_detach_irq - Detach a wakeirq from a wakeup source + * @dev: Device to handle + * + * Removes a device wakeirq from the wakeup source. + * + * Call under the device's power.lock lock. + */ +void device_wakeup_detach_irq(struct device *dev) +{ + struct wakeup_source *ws; + + ws = dev->power.wakeup; + if (ws) + ws->wakeirq = NULL; +} + +/** + * device_wakeup_arm_wake_irqs(void) + * + * Itereates over the list of device wakeirqs to arm them. + */ +void device_wakeup_arm_wake_irqs(void) +{ + struct wakeup_source *ws; + int srcuidx; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) + dev_pm_arm_wake_irq(ws->wakeirq); + srcu_read_unlock(&wakeup_srcu, srcuidx); +} + +/** + * device_wakeup_disarm_wake_irqs(void) + * + * Itereates over the list of device wakeirqs to disarm them. + */ +void device_wakeup_disarm_wake_irqs(void) +{ + struct wakeup_source *ws; + int srcuidx; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) + dev_pm_disarm_wake_irq(ws->wakeirq); + srcu_read_unlock(&wakeup_srcu, srcuidx); +} + +/** + * device_wakeup_detach - Detach a device's wakeup source object from it. + * @dev: Device to detach the wakeup source object from. + * + * After it returns, @dev will not be treated as a wakeup device any more. + */ +static struct wakeup_source *device_wakeup_detach(struct device *dev) +{ + struct wakeup_source *ws; + + spin_lock_irq(&dev->power.lock); + ws = dev->power.wakeup; + dev->power.wakeup = NULL; + spin_unlock_irq(&dev->power.lock); + return ws; +} + +/** + * device_wakeup_disable - Do not regard a device as a wakeup source any more. + * @dev: Device to handle. + * + * Detach the @dev's wakeup source object from it, unregister this wakeup source + * object and destroy it. + */ +int device_wakeup_disable(struct device *dev) +{ + struct wakeup_source *ws; + + if (!dev || !dev->power.can_wakeup) + return -EINVAL; + + ws = device_wakeup_detach(dev); + wakeup_source_unregister(ws); + return 0; +} +EXPORT_SYMBOL_GPL(device_wakeup_disable); + +/** + * device_set_wakeup_capable - Set/reset device wakeup capability flag. + * @dev: Device to handle. + * @capable: Whether or not @dev is capable of waking up the system from sleep. + * + * If @capable is set, set the @dev's power.can_wakeup flag and add its + * wakeup-related attributes to sysfs. Otherwise, unset the @dev's + * power.can_wakeup flag and remove its wakeup-related attributes from sysfs. + * + * This function may sleep and it can't be called from any context where + * sleeping is not allowed. + */ +void device_set_wakeup_capable(struct device *dev, bool capable) +{ + if (!!dev->power.can_wakeup == !!capable) + return; + + dev->power.can_wakeup = capable; + if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { + if (capable) { + int ret = wakeup_sysfs_add(dev); + + if (ret) + dev_info(dev, "Wakeup sysfs attributes not added\n"); + } else { + wakeup_sysfs_remove(dev); + } + } +} +EXPORT_SYMBOL_GPL(device_set_wakeup_capable); + +/** + * device_init_wakeup - Device wakeup initialization. + * @dev: Device to handle. + * @enable: Whether or not to enable @dev as a wakeup device. + * + * By default, most devices should leave wakeup disabled. The exceptions are + * devices that everyone expects to be wakeup sources: keyboards, power buttons, + * possibly network interfaces, etc. Also, devices that don't generate their + * own wakeup requests but merely forward requests from one bus to another + * (like PCI bridges) should have wakeup enabled by default. + */ +int device_init_wakeup(struct device *dev, bool enable) +{ + int ret = 0; + + if (!dev) + return -EINVAL; + + if (enable) { + device_set_wakeup_capable(dev, true); + ret = device_wakeup_enable(dev); + } else { + device_wakeup_disable(dev); + device_set_wakeup_capable(dev, false); + } + + return ret; +} +EXPORT_SYMBOL_GPL(device_init_wakeup); + +/** + * device_set_wakeup_enable - Enable or disable a device to wake up the system. + * @dev: Device to handle. + */ +int device_set_wakeup_enable(struct device *dev, bool enable) +{ + return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev); +} +EXPORT_SYMBOL_GPL(device_set_wakeup_enable); + +/** + * wakeup_source_not_registered - validate the given wakeup source. + * @ws: Wakeup source to be validated. + */ +static bool wakeup_source_not_registered(struct wakeup_source *ws) +{ + /* + * Use timer struct to check if the given source is initialized + * by wakeup_source_add. + */ + return ws->timer.function != pm_wakeup_timer_fn; +} + +/* + * The functions below use the observation that each wakeup event starts a + * period in which the system should not be suspended. The moment this period + * will end depends on how the wakeup event is going to be processed after being + * detected and all of the possible cases can be divided into two distinct + * groups. + * + * First, a wakeup event may be detected by the same functional unit that will + * carry out the entire processing of it and possibly will pass it to user space + * for further processing. In that case the functional unit that has detected + * the event may later "close" the "no suspend" period associated with it + * directly as soon as it has been dealt with. The pair of pm_stay_awake() and + * pm_relax(), balanced with each other, is supposed to be used in such + * situations. + * + * Second, a wakeup event may be detected by one functional unit and processed + * by another one. In that case the unit that has detected it cannot really + * "close" the "no suspend" period associated with it, unless it knows in + * advance what's going to happen to the event during processing. This + * knowledge, however, may not be available to it, so it can simply specify time + * to wait before the system can be suspended and pass it as the second + * argument of pm_wakeup_event(). + * + * It is valid to call pm_relax() after pm_wakeup_event(), in which case the + * "no suspend" period will be ended either by the pm_relax(), or by the timer + * function executed when the timer expires, whichever comes first. + */ + +/** + * wakup_source_activate - Mark given wakeup source as active. + * @ws: Wakeup source to handle. + * + * Update the @ws' statistics and, if @ws has just been activated, notify the PM + * core of the event by incrementing the counter of of wakeup events being + * processed. + */ +static void wakeup_source_activate(struct wakeup_source *ws) +{ + unsigned int cec; + + if (WARN_ONCE(wakeup_source_not_registered(ws), + "unregistered wakeup source\n")) + return; + + ws->active = true; + ws->active_count++; + ws->last_time = ktime_get(); + if (ws->autosleep_enabled) + ws->start_prevent_time = ws->last_time; + + /* Increment the counter of events in progress. */ + cec = atomic_inc_return(&combined_event_count); + + trace_wakeup_source_activate(ws->name, cec); +} + +/** + * wakeup_source_report_event - Report wakeup event using the given source. + * @ws: Wakeup source to report the event for. + * @hard: If set, abort suspends in progress and wake up from suspend-to-idle. + */ +static void wakeup_source_report_event(struct wakeup_source *ws, bool hard) +{ + ws->event_count++; + /* This is racy, but the counter is approximate anyway. */ + if (events_check_enabled) + ws->wakeup_count++; + + if (!ws->active) + wakeup_source_activate(ws); + + if (hard) + pm_system_wakeup(); +} + +/** + * __pm_stay_awake - Notify the PM core of a wakeup event. + * @ws: Wakeup source object associated with the source of the event. + * + * It is safe to call this function from interrupt context. + */ +void __pm_stay_awake(struct wakeup_source *ws) +{ + unsigned long flags; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + + wakeup_source_report_event(ws, false); + del_timer(&ws->timer); + ws->timer_expires = 0; + + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(__pm_stay_awake); + +/** + * pm_stay_awake - Notify the PM core that a wakeup event is being processed. + * @dev: Device the wakeup event is related to. + * + * Notify the PM core of a wakeup event (signaled by @dev) by calling + * __pm_stay_awake for the @dev's wakeup source object. + * + * Call this function after detecting of a wakeup event if pm_relax() is going + * to be called directly after processing the event (and possibly passing it to + * user space for further processing). + */ +void pm_stay_awake(struct device *dev) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + __pm_stay_awake(dev->power.wakeup); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_stay_awake); + +#ifdef CONFIG_PM_AUTOSLEEP +static void update_prevent_sleep_time(struct wakeup_source *ws, ktime_t now) +{ + ktime_t delta = ktime_sub(now, ws->start_prevent_time); + ws->prevent_sleep_time = ktime_add(ws->prevent_sleep_time, delta); +} +#else +static inline void update_prevent_sleep_time(struct wakeup_source *ws, + ktime_t now) {} +#endif + +/** + * wakup_source_deactivate - Mark given wakeup source as inactive. + * @ws: Wakeup source to handle. + * + * Update the @ws' statistics and notify the PM core that the wakeup source has + * become inactive by decrementing the counter of wakeup events being processed + * and incrementing the counter of registered wakeup events. + */ +static void wakeup_source_deactivate(struct wakeup_source *ws) +{ + unsigned int cnt, inpr, cec; + ktime_t duration; + ktime_t now; + + ws->relax_count++; + /* + * __pm_relax() may be called directly or from a timer function. + * If it is called directly right after the timer function has been + * started, but before the timer function calls __pm_relax(), it is + * possible that __pm_stay_awake() will be called in the meantime and + * will set ws->active. Then, ws->active may be cleared immediately + * by the __pm_relax() called from the timer function, but in such a + * case ws->relax_count will be different from ws->active_count. + */ + if (ws->relax_count != ws->active_count) { + ws->relax_count--; + return; + } + + ws->active = false; + + now = ktime_get(); + duration = ktime_sub(now, ws->last_time); + ws->total_time = ktime_add(ws->total_time, duration); + if (ktime_to_ns(duration) > ktime_to_ns(ws->max_time)) + ws->max_time = duration; + + ws->last_time = now; + del_timer(&ws->timer); + ws->timer_expires = 0; + + if (ws->autosleep_enabled) + update_prevent_sleep_time(ws, now); + + /* + * Increment the counter of registered wakeup events and decrement the + * couter of wakeup events in progress simultaneously. + */ + cec = atomic_add_return(MAX_IN_PROGRESS, &combined_event_count); + trace_wakeup_source_deactivate(ws->name, cec); + + split_counters(&cnt, &inpr); + if (!inpr && waitqueue_active(&wakeup_count_wait_queue)) + wake_up(&wakeup_count_wait_queue); +} + +/** + * __pm_relax - Notify the PM core that processing of a wakeup event has ended. + * @ws: Wakeup source object associated with the source of the event. + * + * Call this function for wakeup events whose processing started with calling + * __pm_stay_awake(). + * + * It is safe to call it from interrupt context. + */ +void __pm_relax(struct wakeup_source *ws) +{ + unsigned long flags; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + if (ws->active) + wakeup_source_deactivate(ws); + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(__pm_relax); + +/** + * pm_relax - Notify the PM core that processing of a wakeup event has ended. + * @dev: Device that signaled the event. + * + * Execute __pm_relax() for the @dev's wakeup source object. + */ +void pm_relax(struct device *dev) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + __pm_relax(dev->power.wakeup); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +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 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(struct timer_list *t) +{ + struct wakeup_source *ws = from_timer(ws, t, timer); + 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); + ws->expire_count++; + } + + spin_unlock_irqrestore(&ws->lock, flags); +} + +/** + * pm_wakeup_ws_event - Notify the PM core of a wakeup event. + * @ws: Wakeup source object associated with the event source. + * @msec: Anticipated event processing time (in milliseconds). + * @hard: If set, abort suspends in progress and wake up from suspend-to-idle. + * + * Notify the PM core of a wakeup event whose source is @ws that will take + * approximately @msec milliseconds to be processed by the kernel. If @ws is + * not active, activate it. If @msec is nonzero, set up the @ws' timer to + * execute pm_wakeup_timer_fn() in future. + * + * It is safe to call this function from interrupt context. + */ +void pm_wakeup_ws_event(struct wakeup_source *ws, unsigned int msec, bool hard) +{ + unsigned long flags; + unsigned long expires; + + if (!ws) + return; + + spin_lock_irqsave(&ws->lock, flags); + + wakeup_source_report_event(ws, hard); + + if (!msec) { + wakeup_source_deactivate(ws); + goto unlock; + } + + expires = jiffies + msecs_to_jiffies(msec); + if (!expires) + expires = 1; + + if (!ws->timer_expires || time_after(expires, ws->timer_expires)) { + mod_timer(&ws->timer, expires); + ws->timer_expires = expires; + } + + unlock: + spin_unlock_irqrestore(&ws->lock, flags); +} +EXPORT_SYMBOL_GPL(pm_wakeup_ws_event); + +/** + * pm_wakeup_dev_event - Notify the PM core of a wakeup event. + * @dev: Device the wakeup event is related to. + * @msec: Anticipated event processing time (in milliseconds). + * @hard: If set, abort suspends in progress and wake up from suspend-to-idle. + * + * Call pm_wakeup_ws_event() for the @dev's wakeup source object. + */ +void pm_wakeup_dev_event(struct device *dev, unsigned int msec, bool hard) +{ + unsigned long flags; + + if (!dev) + return; + + spin_lock_irqsave(&dev->power.lock, flags); + pm_wakeup_ws_event(dev->power.wakeup, msec, hard); + spin_unlock_irqrestore(&dev->power.lock, flags); +} +EXPORT_SYMBOL_GPL(pm_wakeup_dev_event); + +void pm_print_active_wakeup_sources(void) +{ + struct wakeup_source *ws; + int srcuidx, active = 0; + struct wakeup_source *last_activity_ws = NULL; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) { + if (ws->active) { + pm_pr_dbg("active wakeup source: %s\n", ws->name); + active = 1; + } else if (!active && + (!last_activity_ws || + ktime_to_ns(ws->last_time) > + ktime_to_ns(last_activity_ws->last_time))) { + last_activity_ws = ws; + } + } + + if (!active && last_activity_ws) + pm_pr_dbg("last active wakeup source: %s\n", + last_activity_ws->name); + srcu_read_unlock(&wakeup_srcu, srcuidx); +} +EXPORT_SYMBOL_GPL(pm_print_active_wakeup_sources); + +/** + * pm_wakeup_pending - Check if power transition in progress should be aborted. + * + * Compare the current number of registered wakeup events with its preserved + * value from the past and return true if new wakeup events have been registered + * since the old value was stored. Also return true if the current number of + * wakeup events being processed is different from zero. + */ +bool pm_wakeup_pending(void) +{ + unsigned long flags; + bool ret = false; + + raw_spin_lock_irqsave(&events_lock, flags); + if (events_check_enabled) { + unsigned int cnt, inpr; + + split_counters(&cnt, &inpr); + ret = (cnt != saved_count || inpr > 0); + events_check_enabled = !ret; + } + raw_spin_unlock_irqrestore(&events_lock, flags); + + if (ret) { + pm_pr_dbg("Wakeup pending, aborting suspend\n"); + pm_print_active_wakeup_sources(); + } + + return ret || atomic_read(&pm_abort_suspend) > 0; +} + +void pm_system_wakeup(void) +{ + atomic_inc(&pm_abort_suspend); + s2idle_wake(); +} +EXPORT_SYMBOL_GPL(pm_system_wakeup); + +void pm_system_cancel_wakeup(void) +{ + atomic_dec_if_positive(&pm_abort_suspend); +} + +void pm_wakeup_clear(unsigned int irq_number) +{ + raw_spin_lock_irq(&wakeup_irq_lock); + + if (irq_number && wakeup_irq[0] == irq_number) + wakeup_irq[0] = wakeup_irq[1]; + else + wakeup_irq[0] = 0; + + wakeup_irq[1] = 0; + + raw_spin_unlock_irq(&wakeup_irq_lock); + + if (!irq_number) + atomic_set(&pm_abort_suspend, 0); +} + +void pm_system_irq_wakeup(unsigned int irq_number) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&wakeup_irq_lock, flags); + + if (wakeup_irq[0] == 0) + wakeup_irq[0] = irq_number; + else if (wakeup_irq[1] == 0) + wakeup_irq[1] = irq_number; + else + irq_number = 0; + + raw_spin_unlock_irqrestore(&wakeup_irq_lock, flags); + + if (irq_number) + pm_system_wakeup(); +} + +unsigned int pm_wakeup_irq(void) +{ + return wakeup_irq[0]; +} + +/** + * pm_get_wakeup_count - Read the number of registered wakeup events. + * @count: Address to store the value at. + * @block: Whether or not to block. + * + * Store the number of registered wakeup events at the address in @count. If + * @block is set, block until the current number of wakeup events being + * processed is zero. + * + * Return 'false' if the current number of wakeup events being processed is + * nonzero. Otherwise return 'true'. + */ +bool pm_get_wakeup_count(unsigned int *count, bool block) +{ + unsigned int cnt, inpr; + + if (block) { + DEFINE_WAIT(wait); + + for (;;) { + prepare_to_wait(&wakeup_count_wait_queue, &wait, + TASK_INTERRUPTIBLE); + split_counters(&cnt, &inpr); + if (inpr == 0 || signal_pending(current)) + break; + pm_print_active_wakeup_sources(); + schedule(); + } + finish_wait(&wakeup_count_wait_queue, &wait); + } + + split_counters(&cnt, &inpr); + *count = cnt; + return !inpr; +} + +/** + * pm_save_wakeup_count - Save the current number of registered wakeup events. + * @count: Value to compare with the current number of registered wakeup events. + * + * If @count is equal to the current number of registered wakeup events and the + * current number of wakeup events being processed is zero, store @count as the + * old number of registered wakeup events for pm_check_wakeup_events(), enable + * wakeup events detection and return 'true'. Otherwise disable wakeup events + * detection and return 'false'. + */ +bool pm_save_wakeup_count(unsigned int count) +{ + unsigned int cnt, inpr; + unsigned long flags; + + events_check_enabled = false; + raw_spin_lock_irqsave(&events_lock, flags); + split_counters(&cnt, &inpr); + if (cnt == count && inpr == 0) { + saved_count = count; + events_check_enabled = true; + } + raw_spin_unlock_irqrestore(&events_lock, flags); + return events_check_enabled; +} + +#ifdef CONFIG_PM_AUTOSLEEP +/** + * pm_wakep_autosleep_enabled - Modify autosleep_enabled for all wakeup sources. + * @enabled: Whether to set or to clear the autosleep_enabled flags. + */ +void pm_wakep_autosleep_enabled(bool set) +{ + struct wakeup_source *ws; + ktime_t now = ktime_get(); + int srcuidx; + + srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) { + spin_lock_irq(&ws->lock); + if (ws->autosleep_enabled != set) { + ws->autosleep_enabled = set; + if (ws->active) { + if (set) + ws->start_prevent_time = now; + else + update_prevent_sleep_time(ws, now); + } + } + spin_unlock_irq(&ws->lock); + } + srcu_read_unlock(&wakeup_srcu, srcuidx); +} +#endif /* CONFIG_PM_AUTOSLEEP */ + +/** + * print_wakeup_source_stats - Print wakeup source statistics information. + * @m: seq_file to print the statistics into. + * @ws: Wakeup source object to print the statistics for. + */ +static int print_wakeup_source_stats(struct seq_file *m, + struct wakeup_source *ws) +{ + unsigned long flags; + ktime_t total_time; + ktime_t max_time; + unsigned long active_count; + ktime_t active_time; + ktime_t prevent_sleep_time; + + spin_lock_irqsave(&ws->lock, flags); + + total_time = ws->total_time; + max_time = ws->max_time; + prevent_sleep_time = ws->prevent_sleep_time; + active_count = ws->active_count; + if (ws->active) { + ktime_t now = ktime_get(); + + active_time = ktime_sub(now, ws->last_time); + total_time = ktime_add(total_time, active_time); + if (active_time > max_time) + max_time = active_time; + + if (ws->autosleep_enabled) + prevent_sleep_time = ktime_add(prevent_sleep_time, + ktime_sub(now, ws->start_prevent_time)); + } else { + active_time = 0; + } + + seq_printf(m, "%-12s\t%lu\t\t%lu\t\t%lu\t\t%lu\t\t%lld\t\t%lld\t\t%lld\t\t%lld\t\t%lld\n", + ws->name, active_count, ws->event_count, + ws->wakeup_count, ws->expire_count, + ktime_to_ms(active_time), ktime_to_ms(total_time), + ktime_to_ms(max_time), ktime_to_ms(ws->last_time), + ktime_to_ms(prevent_sleep_time)); + + spin_unlock_irqrestore(&ws->lock, flags); + + return 0; +} + +static void *wakeup_sources_stats_seq_start(struct seq_file *m, + loff_t *pos) +{ + struct wakeup_source *ws; + loff_t n = *pos; + int *srcuidx = m->private; + + if (n == 0) { + seq_puts(m, "name\t\tactive_count\tevent_count\twakeup_count\t" + "expire_count\tactive_since\ttotal_time\tmax_time\t" + "last_change\tprevent_suspend_time\n"); + } + + *srcuidx = srcu_read_lock(&wakeup_srcu); + list_for_each_entry_rcu_locked(ws, &wakeup_sources, entry) { + if (n-- <= 0) + return ws; + } + + return NULL; +} + +static void *wakeup_sources_stats_seq_next(struct seq_file *m, + void *v, loff_t *pos) +{ + struct wakeup_source *ws = v; + struct wakeup_source *next_ws = NULL; + + ++(*pos); + + list_for_each_entry_continue_rcu(ws, &wakeup_sources, entry) { + next_ws = ws; + break; + } + + if (!next_ws) + print_wakeup_source_stats(m, &deleted_ws); + + return next_ws; +} + +static void wakeup_sources_stats_seq_stop(struct seq_file *m, void *v) +{ + int *srcuidx = m->private; + + srcu_read_unlock(&wakeup_srcu, *srcuidx); +} + +/** + * wakeup_sources_stats_seq_show - Print wakeup sources statistics information. + * @m: seq_file to print the statistics into. + * @v: wakeup_source of each iteration + */ +static int wakeup_sources_stats_seq_show(struct seq_file *m, void *v) +{ + struct wakeup_source *ws = v; + + print_wakeup_source_stats(m, ws); + + return 0; +} + +static const struct seq_operations wakeup_sources_stats_seq_ops = { + .start = wakeup_sources_stats_seq_start, + .next = wakeup_sources_stats_seq_next, + .stop = wakeup_sources_stats_seq_stop, + .show = wakeup_sources_stats_seq_show, +}; + +static int wakeup_sources_stats_open(struct inode *inode, struct file *file) +{ + return seq_open_private(file, &wakeup_sources_stats_seq_ops, sizeof(int)); +} + +static const struct file_operations wakeup_sources_stats_fops = { + .owner = THIS_MODULE, + .open = wakeup_sources_stats_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_private, +}; + +static int __init wakeup_sources_debugfs_init(void) +{ + debugfs_create_file("wakeup_sources", S_IRUGO, NULL, NULL, + &wakeup_sources_stats_fops); + return 0; +} + +postcore_initcall(wakeup_sources_debugfs_init); |