Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1188 insertions, 0 deletions

diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
new file mode 100644
index 000000000..7cc0c0cf8
--- /dev/null
+++ b/drivers/base/power/wakeup.c
@@ -0,0 +1,1188 @@
+// 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 -
+ *
+ * Iterates 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 -
+ *
+ * Iterates 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_set_wakeup_enable - Enable or disable a device to wake up the system.
+ * @dev: Device to handle.
+ * @enable: enable/disable flag
+ */
+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.
+ */
+
+/**
+ * wakeup_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 the 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
+
+/**
+ * wakeup_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
+	 * counter 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.
+ * @t: timer list
+ *
+ * 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;
+}
+EXPORT_SYMBOL_GPL(pm_wakeup_pending);
+
+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;
+
+	pm_pr_dbg("Triggering wakeup from IRQ %d\n", irq_number);
+
+	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.
+ * @set: 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", 0444, NULL, NULL,
+			    &wakeup_sources_stats_fops);
+	return 0;
+}
+
+postcore_initcall(wakeup_sources_debugfs_init);