linux-imx

/*

 * 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.

 */

​

#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

​

/*

 * 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. */

unsigned int pm_wakeup_irq __read_mostly;

​

/* 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),

};

​

/**

 * 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);