--- /dev/null
+/*
+ * drivers/base/power/wakeup.c - System wakeup events framework
+ *
+ * Copyright (c) 2010 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/capability.h>
+#include <linux/export.h>
+#include <linux/suspend.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <trace/events/power.h>
+
+#include "power.h"
+
+/*
+ * 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;
+
+/* If set and the system is suspending, terminate the suspend. */
+static bool 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_SPINLOCK(events_lock);
+
+static void pm_wakeup_timer_fn(unsigned long data);
+
+static LIST_HEAD(wakeup_sources);
+
+static DECLARE_WAIT_QUEUE_HEAD(wakeup_count_wait_queue);
+
+/**
+ * wakeup_source_prepare - Prepare a new wakeup source for initialization.
+ * @ws: Wakeup source to prepare.
+ * @name: Pointer to the name of the new wakeup source.
+ *
+ * Callers must ensure that the @name string won't be freed when @ws is still in
+ * use.
+ */
+void wakeup_source_prepare(struct wakeup_source *ws, const char *name)
+{
+ if (ws) {
+ memset(ws, 0, sizeof(*ws));
+ ws->name = name;
+ }
+}
+EXPORT_SYMBOL_GPL(wakeup_source_prepare);
+
+/**
+ * wakeup_source_create - Create a struct wakeup_source object.
+ * @name: Name of the new wakeup source.
+ */
+struct wakeup_source *wakeup_source_create(const char *name)
+{
+ struct wakeup_source *ws;
+
+ ws = kmalloc(sizeof(*ws), GFP_KERNEL);
+ if (!ws)
+ return NULL;
+
+ wakeup_source_prepare(ws, name ? kstrdup(name, GFP_KERNEL) : NULL);
+ return ws;
+}
+EXPORT_SYMBOL_GPL(wakeup_source_create);
+
+/**
+ * wakeup_source_drop - Prepare a struct wakeup_source object for destruction.
+ * @ws: Wakeup source to prepare for destruction.
+ *
+ * Callers must ensure that __pm_stay_awake() or __pm_wakeup_event() will never
+ * be run in parallel with this function for the same wakeup source object.
+ */
+void wakeup_source_drop(struct wakeup_source *ws)
+{
+ if (!ws)
+ return;
+
+ del_timer_sync(&ws->timer);
+ __pm_relax(ws);
+}
+EXPORT_SYMBOL_GPL(wakeup_source_drop);
+
+/**
+ * wakeup_source_destroy - Destroy a struct wakeup_source object.
+ * @ws: Wakeup source to destroy.
+ *
+ * Use only for wakeup source objects created with wakeup_source_create().
+ */
+void wakeup_source_destroy(struct wakeup_source *ws)
+{
+ if (!ws)
+ return;
+
+ wakeup_source_drop(ws);
+ kfree(ws->name);
+ kfree(ws);
+}
+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);
+ setup_timer(&ws->timer, pm_wakeup_timer_fn, (unsigned long)ws);
+ ws->active = false;
+ ws->last_time = ktime_get();
+
+ spin_lock_irqsave(&events_lock, flags);
+ list_add_rcu(&ws->entry, &wakeup_sources);
+ 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;
+
+ spin_lock_irqsave(&events_lock, flags);
+ list_del_rcu(&ws->entry);
+ spin_unlock_irqrestore(&events_lock, flags);
+ synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(wakeup_source_remove);
+
+/**
+ * wakeup_source_register - Create wakeup source and add it to the list.
+ * @name: Name of the wakeup source to register.
+ */
+struct wakeup_source *wakeup_source_register(const char *name)
+{
+ struct wakeup_source *ws;
+
+ ws = wakeup_source_create(name);
+ if (ws)
+ 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);
+ wakeup_source_destroy(ws);
+ }
+}
+EXPORT_SYMBOL_GPL(wakeup_source_unregister);
+
+/**
+ * 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;
+ 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;
+
+ ws = wakeup_source_register(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_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);
+ if (ws)
+ 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;
+
+ if (device_is_registered(dev) && !list_empty(&dev->power.entry)) {
+ if (capable) {
+ if (wakeup_sysfs_add(dev))
+ return;
+ } else {
+ wakeup_sysfs_remove(dev);
+ }
+ }
+ dev->power.can_wakeup = capable;
+}
+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 {
+ if (dev->power.can_wakeup)
+ 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)
+{
+ if (!dev || !dev->power.can_wakeup)
+ return -EINVAL;
+
+ return enable ? device_wakeup_enable(dev) : device_wakeup_disable(dev);
+}
+EXPORT_SYMBOL_GPL(device_set_wakeup_enable);
+
+/*
+ * 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;
+
+ /*
+ * active wakeup source should bring the system
+ * out of PM_SUSPEND_FREEZE state
+ */
+ freeze_wake();
+
+ 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.
+ */
+static void wakeup_source_report_event(struct wakeup_source *ws)
+{
+ 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);
+}
+
+/**
+ * __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);
+ 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(unsigned long data)
+{
+ struct wakeup_source *ws = (struct wakeup_source *)data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ws->lock, flags);
+
+ if (ws->active && ws->timer_expires
+ && time_after_eq(jiffies, ws->timer_expires)) {
+ wakeup_source_deactivate(ws);
+ ws->expire_count++;
+ }
+
+ spin_unlock_irqrestore(&ws->lock, flags);
+}
+
+/**
+ * __pm_wakeup_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).
+ *
+ * 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_event(struct wakeup_source *ws, unsigned int msec)
+{
+ unsigned long flags;
+ unsigned long expires;
+
+ if (!ws)
+ return;
+
+ spin_lock_irqsave(&ws->lock, flags);
+
+ wakeup_source_report_event(ws);
+
+ 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_event);
+
+
+/**
+ * pm_wakeup_event - Notify the PM core of a wakeup event.
+ * @dev: Device the wakeup event is related to.
+ * @msec: Anticipated event processing time (in milliseconds).
+ *
+ * Call __pm_wakeup_event() for the @dev's wakeup source object.
+ */
+void pm_wakeup_event(struct device *dev, unsigned int msec)
+{
+ unsigned long flags;
+
+ if (!dev)
+ return;
+
+ spin_lock_irqsave(&dev->power.lock, flags);
+ __pm_wakeup_event(dev->power.wakeup, msec);
+ spin_unlock_irqrestore(&dev->power.lock, flags);
+}
+EXPORT_SYMBOL_GPL(pm_wakeup_event);
+
+void pm_print_active_wakeup_sources(void)
+{
+ struct wakeup_source *ws;
+ int active = 0;
+ struct wakeup_source *last_activity_ws = NULL;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
+ if (ws->active) {
+ pr_info("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)
+ pr_info("last active wakeup source: %s\n",
+ last_activity_ws->name);
+ rcu_read_unlock();
+}
+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;
+
+ 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;
+ }
+ spin_unlock_irqrestore(&events_lock, flags);
+
+ if (ret) {
+ pr_info("PM: Wakeup pending, aborting suspend\n");
+ pm_print_active_wakeup_sources();
+ }
+
+ return ret || pm_abort_suspend;
+}
+
+void pm_system_wakeup(void)
+{
+ pm_abort_suspend = true;
+ freeze_wake();
+}
+EXPORT_SYMBOL_GPL(pm_system_wakeup);
+
+void pm_wakeup_clear(void)
+{
+ pm_abort_suspend = false;
+}
+
+/**
+ * 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;
+
+ 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;
+ spin_lock_irqsave(&events_lock, flags);
+ split_counters(&cnt, &inpr);
+ if (cnt == count && inpr == 0) {
+ saved_count = count;
+ events_check_enabled = true;
+ }
+ 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();
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(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);
+ }
+ rcu_read_unlock();
+}
+#endif /* CONFIG_PM_AUTOSLEEP */
+
+static struct dentry *wakeup_sources_stats_dentry;
+
+/**
+ * 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.tv64 > max_time.tv64)
+ 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 = ktime_set(0, 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;
+}
+
+/**
+ * wakeup_sources_stats_show - Print wakeup sources statistics information.
+ * @m: seq_file to print the statistics into.
+ */
+static int wakeup_sources_stats_show(struct seq_file *m, void *unused)
+{
+ struct wakeup_source *ws;
+
+ 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");
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ws, &wakeup_sources, entry)
+ print_wakeup_source_stats(m, ws);
+ rcu_read_unlock();
+
+ return 0;
+}
+
+static int wakeup_sources_stats_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, wakeup_sources_stats_show, NULL);
+}
+
+static const struct file_operations wakeup_sources_stats_fops = {
+ .owner = THIS_MODULE,
+ .open = wakeup_sources_stats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static int __init wakeup_sources_debugfs_init(void)
+{
+ wakeup_sources_stats_dentry = debugfs_create_file("wakeup_sources",
+ S_IRUGO, NULL, NULL, &wakeup_sources_stats_fops);
+ return 0;
+}
+
+postcore_initcall(wakeup_sources_debugfs_init);
Code Review / kvmfornfv.git / blobdiff