[mirror_ubuntu-artful-kernel.git] / kernel / power / suspend.c

/*
 * kernel/power/suspend.c - Suspend to RAM and standby functionality.
 *
 * Copyright (c) 2003 Patrick Mochel
 * Copyright (c) 2003 Open Source Development Lab
 * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
 *
 * This file is released under the GPLv2.
 */

#include <linux/string.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/cpu.h>
#include <linux/cpuidle.h>
#include <linux/syscalls.h>
#include <linux/gfp.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/suspend.h>
#include <linux/syscore_ops.h>
#include <linux/ftrace.h>
#include <trace/events/power.h>
#include <linux/compiler.h>

#include "power.h"

const char *pm_labels[] = { "mem", "standby", "freeze", NULL };
const char *pm_states[PM_SUSPEND_MAX];

static const struct platform_suspend_ops *suspend_ops;
static const struct platform_freeze_ops *freeze_ops;
static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head);

enum freeze_state __read_mostly suspend_freeze_state;
static DEFINE_SPINLOCK(suspend_freeze_lock);

void freeze_set_ops(const struct platform_freeze_ops *ops)
{
	lock_system_sleep();
	freeze_ops = ops;
	unlock_system_sleep();
}

static void freeze_begin(void)
{
	suspend_freeze_state = FREEZE_STATE_NONE;
}

static void freeze_enter(void)
{
	spin_lock_irq(&suspend_freeze_lock);
	if (pm_wakeup_pending())
		goto out;

	suspend_freeze_state = FREEZE_STATE_ENTER;
	spin_unlock_irq(&suspend_freeze_lock);

	get_online_cpus();
	cpuidle_resume();

	/* Push all the CPUs into the idle loop. */
	wake_up_all_idle_cpus();
	pr_debug("PM: suspend-to-idle\n");
	/* Make the current CPU wait so it can enter the idle loop too. */
	wait_event(suspend_freeze_wait_head,
		   suspend_freeze_state == FREEZE_STATE_WAKE);
	pr_debug("PM: resume from suspend-to-idle\n");

	cpuidle_pause();
	put_online_cpus();

	spin_lock_irq(&suspend_freeze_lock);

 out:
	suspend_freeze_state = FREEZE_STATE_NONE;
	spin_unlock_irq(&suspend_freeze_lock);
}

void freeze_wake(void)
{
	unsigned long flags;

	spin_lock_irqsave(&suspend_freeze_lock, flags);
	if (suspend_freeze_state > FREEZE_STATE_NONE) {
		suspend_freeze_state = FREEZE_STATE_WAKE;
		wake_up(&suspend_freeze_wait_head);
	}
	spin_unlock_irqrestore(&suspend_freeze_lock, flags);
}
EXPORT_SYMBOL_GPL(freeze_wake);

static bool valid_state(suspend_state_t state)
{
	/*
	 * PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
	 * support and need to be valid to the low level
	 * implementation, no valid callback implies that none are valid.
	 */
	return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
}

/*
 * If this is set, the "mem" label always corresponds to the deepest sleep state
 * available, the "standby" label corresponds to the second deepest sleep state
 * available (if any), and the "freeze" label corresponds to the remaining
 * available sleep state (if there is one).
 */
static bool relative_states;

static int __init sleep_states_setup(char *str)
{
	relative_states = !strncmp(str, "1", 1);
	pm_states[PM_SUSPEND_FREEZE] = pm_labels[relative_states ? 0 : 2];
	return 1;
}

__setup("relative_sleep_states=", sleep_states_setup);

/**
 * suspend_set_ops - Set the global suspend method table.
 * @ops: Suspend operations to use.
 */
void suspend_set_ops(const struct platform_suspend_ops *ops)
{
	suspend_state_t i;
	int j = 0;

	lock_system_sleep();

	suspend_ops = ops;
	for (i = PM_SUSPEND_MEM; i >= PM_SUSPEND_STANDBY; i--)
		if (valid_state(i)) {
			pm_states[i] = pm_labels[j++];
		} else if (!relative_states) {
			pm_states[i] = NULL;
			j++;
		}

	pm_states[PM_SUSPEND_FREEZE] = pm_labels[j];

	unlock_system_sleep();
}
EXPORT_SYMBOL_GPL(suspend_set_ops);

/**
 * suspend_valid_only_mem - Generic memory-only valid callback.
 *
 * Platform drivers that implement mem suspend only and only need to check for
 * that in their .valid() callback can use this instead of rolling their own
 * .valid() callback.
 */
int suspend_valid_only_mem(suspend_state_t state)
{
	return state == PM_SUSPEND_MEM;
}
EXPORT_SYMBOL_GPL(suspend_valid_only_mem);

static bool sleep_state_supported(suspend_state_t state)
{
	return state == PM_SUSPEND_FREEZE || (suspend_ops && suspend_ops->enter);
}

static int platform_suspend_prepare(suspend_state_t state)
{
	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare ?
		suspend_ops->prepare() : 0;
}

static int platform_suspend_prepare_late(suspend_state_t state)
{
	return state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->prepare ?
		freeze_ops->prepare() : 0;
}

static int platform_suspend_prepare_noirq(suspend_state_t state)
{
	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare_late ?
		suspend_ops->prepare_late() : 0;
}

static void platform_resume_noirq(suspend_state_t state)
{
	if (state != PM_SUSPEND_FREEZE && suspend_ops->wake)
		suspend_ops->wake();
}

static void platform_resume_early(suspend_state_t state)
{
	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->restore)
		freeze_ops->restore();
}

static void platform_resume_finish(suspend_state_t state)
{
	if (state != PM_SUSPEND_FREEZE && suspend_ops->finish)
		suspend_ops->finish();
}

static int platform_suspend_begin(suspend_state_t state)
{
	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->begin)
		return freeze_ops->begin();
	else if (suspend_ops->begin)
		return suspend_ops->begin(state);
	else
		return 0;
}

static void platform_resume_end(suspend_state_t state)
{
	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
		freeze_ops->end();
	else if (suspend_ops->end)
		suspend_ops->end();
}

static void platform_recover(suspend_state_t state)
{
	if (state != PM_SUSPEND_FREEZE && suspend_ops->recover)
		suspend_ops->recover();
}

static bool platform_suspend_again(suspend_state_t state)
{
	return state != PM_SUSPEND_FREEZE && suspend_ops->suspend_again ?
		suspend_ops->suspend_again() : false;
}

static int suspend_test(int level)
{
#ifdef CONFIG_PM_DEBUG
	if (pm_test_level == level) {
		printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n");
		mdelay(5000);
		return 1;
	}
#endif /* !CONFIG_PM_DEBUG */
	return 0;
}

/**
 * suspend_prepare - Prepare for entering system sleep state.
 *
 * Common code run for every system sleep state that can be entered (except for
 * hibernation).  Run suspend notifiers, allocate the "suspend" console and
 * freeze processes.
 */
static int suspend_prepare(suspend_state_t state)
{
	int error;

	if (!sleep_state_supported(state))
		return -EPERM;

	pm_prepare_console();

	error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
	if (error)
		goto Finish;

	trace_suspend_resume(TPS("freeze_processes"), 0, true);
	error = suspend_freeze_processes();
	trace_suspend_resume(TPS("freeze_processes"), 0, false);
	if (!error)
		return 0;

	suspend_stats.failed_freeze++;
	dpm_save_failed_step(SUSPEND_FREEZE);
 Finish:
	pm_notifier_call_chain(PM_POST_SUSPEND);
	pm_restore_console();
	return error;
}

/* default implementation */
void __weak arch_suspend_disable_irqs(void)
{
	local_irq_disable();
}

/* default implementation */
void __weak arch_suspend_enable_irqs(void)
{
	local_irq_enable();
}

/**
 * suspend_enter - Make the system enter the given sleep state.
 * @state: System sleep state to enter.
 * @wakeup: Returns information that the sleep state should not be re-entered.
 *
 * This function should be called after devices have been suspended.
 */
static int suspend_enter(suspend_state_t state, bool *wakeup)
{
	int error;

	error = platform_suspend_prepare(state);
	if (error)
		goto Platform_finish;

	error = dpm_suspend_late(PMSG_SUSPEND);
	if (error) {
		printk(KERN_ERR "PM: late suspend of devices failed\n");
		goto Platform_finish;
	}
	error = platform_suspend_prepare_late(state);
	if (error)
		goto Devices_early_resume;

	error = dpm_suspend_noirq(PMSG_SUSPEND);
	if (error) {
		printk(KERN_ERR "PM: noirq suspend of devices failed\n");
		goto Platform_early_resume;
	}
	error = platform_suspend_prepare_noirq(state);
	if (error)
		goto Platform_wake;

	if (suspend_test(TEST_PLATFORM))
		goto Platform_wake;

	/*
	 * PM_SUSPEND_FREEZE equals
	 * frozen processes + suspended devices + idle processors.
	 * Thus we should invoke freeze_enter() soon after
	 * all the devices are suspended.
	 */
	if (state == PM_SUSPEND_FREEZE) {
		trace_suspend_resume(TPS("machine_suspend"), state, true);
		freeze_enter();
		trace_suspend_resume(TPS("machine_suspend"), state, false);
		goto Platform_wake;
	}

	error = disable_nonboot_cpus();
	if (error || suspend_test(TEST_CPUS))
		goto Enable_cpus;

	arch_suspend_disable_irqs();
	BUG_ON(!irqs_disabled());

	error = syscore_suspend();
	if (!error) {
		*wakeup = pm_wakeup_pending();
		if (!(suspend_test(TEST_CORE) || *wakeup)) {
			trace_suspend_resume(TPS("machine_suspend"),
				state, true);
			error = suspend_ops->enter(state);
			trace_suspend_resume(TPS("machine_suspend"),
				state, false);
			events_check_enabled = false;
		}
		syscore_resume();
	}

	arch_suspend_enable_irqs();
	BUG_ON(irqs_disabled());

 Enable_cpus:
	enable_nonboot_cpus();

 Platform_wake:
	platform_resume_noirq(state);
	dpm_resume_noirq(PMSG_RESUME);

 Platform_early_resume:
	platform_resume_early(state);

 Devices_early_resume:
	dpm_resume_early(PMSG_RESUME);

 Platform_finish:
	platform_resume_finish(state);
	return error;
}

/**
 * suspend_devices_and_enter - Suspend devices and enter system sleep state.
 * @state: System sleep state to enter.
 */
int suspend_devices_and_enter(suspend_state_t state)
{
	int error;
	bool wakeup = false;

	if (!sleep_state_supported(state))
		return -ENOSYS;

	error = platform_suspend_begin(state);
	if (error)
		goto Close;

	suspend_console();
	suspend_test_start();
	error = dpm_suspend_start(PMSG_SUSPEND);
	if (error) {
		pr_err("PM: Some devices failed to suspend, or early wake event detected\n");
		goto Recover_platform;
	}
	suspend_test_finish("suspend devices");
	if (suspend_test(TEST_DEVICES))
		goto Recover_platform;

	do {
		error = suspend_enter(state, &wakeup);
	} while (!error && !wakeup && platform_suspend_again(state));

 Resume_devices:
	suspend_test_start();
	dpm_resume_end(PMSG_RESUME);
	suspend_test_finish("resume devices");
	trace_suspend_resume(TPS("resume_console"), state, true);
	resume_console();
	trace_suspend_resume(TPS("resume_console"), state, false);

 Close:
	platform_resume_end(state);
	return error;

 Recover_platform:
	platform_recover(state);
	goto Resume_devices;
}

/**
 * suspend_finish - Clean up before finishing the suspend sequence.
 *
 * Call platform code to clean up, restart processes, and free the console that
 * we've allocated. This routine is not called for hibernation.
 */
static void suspend_finish(void)
{
	suspend_thaw_processes();
	pm_notifier_call_chain(PM_POST_SUSPEND);
	pm_restore_console();
}

/**
 * enter_state - Do common work needed to enter system sleep state.
 * @state: System sleep state to enter.
 *
 * Make sure that no one else is trying to put the system into a sleep state.
 * Fail if that's not the case.  Otherwise, prepare for system suspend, make the
 * system enter the given sleep state and clean up after wakeup.
 */
static int enter_state(suspend_state_t state)
{
	int error;

	trace_suspend_resume(TPS("suspend_enter"), state, true);
	if (state == PM_SUSPEND_FREEZE) {
#ifdef CONFIG_PM_DEBUG
		if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
			pr_warning("PM: Unsupported test mode for freeze state,"
				   "please choose none/freezer/devices/platform.\n");
			return -EAGAIN;
		}
#endif
	} else if (!valid_state(state)) {
		return -EINVAL;
	}
	if (!mutex_trylock(&pm_mutex))
		return -EBUSY;

	if (state == PM_SUSPEND_FREEZE)
		freeze_begin();

	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
	printk(KERN_INFO "PM: Syncing filesystems ... ");
	sys_sync();
	printk("done.\n");
	trace_suspend_resume(TPS("sync_filesystems"), 0, false);

	pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]);
	error = suspend_prepare(state);
	if (error)
		goto Unlock;

	if (suspend_test(TEST_FREEZER))
		goto Finish;

	trace_suspend_resume(TPS("suspend_enter"), state, false);
	pr_debug("PM: Entering %s sleep\n", pm_states[state]);
	pm_restrict_gfp_mask();
	error = suspend_devices_and_enter(state);
	pm_restore_gfp_mask();

 Finish:
	pr_debug("PM: Finishing wakeup.\n");
	suspend_finish();
 Unlock:
	mutex_unlock(&pm_mutex);
	return error;
}

/**
 * pm_suspend - Externally visible function for suspending the system.
 * @state: System sleep state to enter.
 *
 * Check if the value of @state represents one of the supported states,
 * execute enter_state() and update system suspend statistics.
 */
int pm_suspend(suspend_state_t state)
{
	int error;

	if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX)
		return -EINVAL;

	error = enter_state(state);
	if (error) {
		suspend_stats.fail++;
		dpm_save_failed_errno(error);
	} else {
		suspend_stats.success++;
	}
	return error;
}
EXPORT_SYMBOL(pm_suspend);
Commit	Line	Data
a9d70523 RW	1	/*
	2	* kernel/power/suspend.c - Suspend to RAM and standby functionality.
	3	*
	4	* Copyright (c) 2003 Patrick Mochel
	5	* Copyright (c) 2003 Open Source Development Lab
	6	* Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
	7	*
	8	* This file is released under the GPLv2.
	9	*/
	10
	11	#include <linux/string.h>
	12	#include <linux/delay.h>
	13	#include <linux/errno.h>
	14	#include <linux/init.h>
	15	#include <linux/console.h>
	16	#include <linux/cpu.h>
f3f12532	17	#include <linux/cpuidle.h>
a9d70523	18	#include <linux/syscalls.h>
5a0e3ad6	19	#include <linux/gfp.h>
dd4c4f17 MG	20	#include <linux/io.h>
	21	#include <linux/kernel.h>
	22	#include <linux/list.h>
	23	#include <linux/mm.h>
	24	#include <linux/slab.h>
6e5fdeed	25	#include <linux/export.h>
dd4c4f17	26	#include <linux/suspend.h>
40dc166c	27	#include <linux/syscore_ops.h>
443772d4	28	#include <linux/ftrace.h>
938cfed1	29	#include <trace/events/power.h>
52f5684c	30	#include <linux/compiler.h>
a9d70523 RW	31
	32	#include "power.h"
	33
62109b43	34	const char *pm_labels[] = { "mem", "standby", "freeze", NULL };
d431cbc5	35	const char *pm_states[PM_SUSPEND_MAX];
a9d70523	36
2f55ac07	37	static const struct platform_suspend_ops *suspend_ops;
1f0b6386	38	static const struct platform_freeze_ops *freeze_ops;
7e73c5ae	39	static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head);
38106313 RW	40
	41	enum freeze_state __read_mostly suspend_freeze_state;
	42	static DEFINE_SPINLOCK(suspend_freeze_lock);
7e73c5ae	43
1f0b6386 RW	44	void freeze_set_ops(const struct platform_freeze_ops *ops)
	45	{
	46	lock_system_sleep();
	47	freeze_ops = ops;
	48	unlock_system_sleep();
	49	}
	50
7e73c5ae ZR	51	static void freeze_begin(void)
7e73c5ae ZR	52	{
38106313	53	suspend_freeze_state = FREEZE_STATE_NONE;
7e73c5ae ZR	54	}
	55
	56	static void freeze_enter(void)
	57	{
38106313 RW	58	spin_lock_irq(&suspend_freeze_lock);
	59	if (pm_wakeup_pending())
	60	goto out;
	61
	62	suspend_freeze_state = FREEZE_STATE_ENTER;
	63	spin_unlock_irq(&suspend_freeze_lock);
	64
	65	get_online_cpus();
f3f12532	66	cpuidle_resume();
38106313 RW	67
	68	/* Push all the CPUs into the idle loop. */
	69	wake_up_all_idle_cpus();
	70	pr_debug("PM: suspend-to-idle\n");
	71	/* Make the current CPU wait so it can enter the idle loop too. */
	72	wait_event(suspend_freeze_wait_head,
	73	suspend_freeze_state == FREEZE_STATE_WAKE);
	74	pr_debug("PM: resume from suspend-to-idle\n");
	75
f3f12532	76	cpuidle_pause();
38106313 RW	77	put_online_cpus();
	78
	79	spin_lock_irq(&suspend_freeze_lock);
	80
	81	out:
	82	suspend_freeze_state = FREEZE_STATE_NONE;
	83	spin_unlock_irq(&suspend_freeze_lock);
7e73c5ae ZR	84	}
	85
	86	void freeze_wake(void)
	87	{
38106313 RW	88	unsigned long flags;
	89
	90	spin_lock_irqsave(&suspend_freeze_lock, flags);
	91	if (suspend_freeze_state > FREEZE_STATE_NONE) {
	92	suspend_freeze_state = FREEZE_STATE_WAKE;
	93	wake_up(&suspend_freeze_wait_head);
	94	}
	95	spin_unlock_irqrestore(&suspend_freeze_lock, flags);
7e73c5ae ZR	96	}
	97	EXPORT_SYMBOL_GPL(freeze_wake);
	98
43e8317b RW	99	static bool valid_state(suspend_state_t state)
	100	{
	101	/*
	102	* PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
	103	* support and need to be valid to the low level
	104	* implementation, no valid callback implies that none are valid.
	105	*/
	106	return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
	107	}
	108
0399d4db RW	109	/*
	110	* If this is set, the "mem" label always corresponds to the deepest sleep state
	111	* available, the "standby" label corresponds to the second deepest sleep state
	112	* available (if any), and the "freeze" label corresponds to the remaining
	113	* available sleep state (if there is one).
	114	*/
	115	static bool relative_states;
	116
	117	static int __init sleep_states_setup(char *str)
	118	{
	119	relative_states = !strncmp(str, "1", 1);
d431cbc5	120	pm_states[PM_SUSPEND_FREEZE] = pm_labels[relative_states ? 0 : 2];
0399d4db RW	121	return 1;
	122	}
	123
	124	__setup("relative_sleep_states=", sleep_states_setup);
	125
a9d70523	126	/**
55ae4519 RW	127	* suspend_set_ops - Set the global suspend method table.
55ae4519 RW	128	* @ops: Suspend operations to use.
a9d70523	129	*/
2f55ac07	130	void suspend_set_ops(const struct platform_suspend_ops *ops)
a9d70523	131	{
43e8317b	132	suspend_state_t i;
d431cbc5	133	int j = 0;
43e8317b	134
bcda53fa	135	lock_system_sleep();
43e8317b	136
a9d70523	137	suspend_ops = ops;
0399d4db	138	for (i = PM_SUSPEND_MEM; i >= PM_SUSPEND_STANDBY; i--)
d431cbc5 RW	139	if (valid_state(i)) {
	140	pm_states[i] = pm_labels[j++];
	141	} else if (!relative_states) {
	142	pm_states[i] = NULL;
	143	j++;
	144	}
0399d4db	145
d431cbc5	146	pm_states[PM_SUSPEND_FREEZE] = pm_labels[j];
43e8317b	147
bcda53fa	148	unlock_system_sleep();
a9d70523	149	}
a5e4fd87	150	EXPORT_SYMBOL_GPL(suspend_set_ops);
a9d70523	151
a9d70523	152	/**
55ae4519	153	* suspend_valid_only_mem - Generic memory-only valid callback.
a9d70523	154	*
55ae4519 RW	155	* Platform drivers that implement mem suspend only and only need to check for
	156	* that in their .valid() callback can use this instead of rolling their own
	157	* .valid() callback.
a9d70523 RW	158	*/
	159	int suspend_valid_only_mem(suspend_state_t state)
	160	{
	161	return state == PM_SUSPEND_MEM;
	162	}
a5e4fd87	163	EXPORT_SYMBOL_GPL(suspend_valid_only_mem);
a9d70523	164
8490fdf9 RW	165	static bool sleep_state_supported(suspend_state_t state)
	166	{
	167	return state == PM_SUSPEND_FREEZE \|\| (suspend_ops && suspend_ops->enter);
	168	}
	169
	170	static int platform_suspend_prepare(suspend_state_t state)
	171	{
	172	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare ?
	173	suspend_ops->prepare() : 0;
	174	}
	175
a8d46b9e RW	176	static int platform_suspend_prepare_late(suspend_state_t state)
a8d46b9e RW	177	{
403b9636	178	return state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->prepare ?
a8d46b9e RW	179	freeze_ops->prepare() : 0;
	180	}
	181
ebc3e41e	182	static int platform_suspend_prepare_noirq(suspend_state_t state)
8490fdf9 RW	183	{
	184	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare_late ?
	185	suspend_ops->prepare_late() : 0;
	186	}
	187
ebc3e41e	188	static void platform_resume_noirq(suspend_state_t state)
8490fdf9 RW	189	{
	190	if (state != PM_SUSPEND_FREEZE && suspend_ops->wake)
	191	suspend_ops->wake();
	192	}
	193
a8d46b9e RW	194	static void platform_resume_early(suspend_state_t state)
a8d46b9e RW	195	{
403b9636	196	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->restore)
a8d46b9e RW	197	freeze_ops->restore();
	198	}
	199
ebc3e41e	200	static void platform_resume_finish(suspend_state_t state)
8490fdf9 RW	201	{
	202	if (state != PM_SUSPEND_FREEZE && suspend_ops->finish)
	203	suspend_ops->finish();
	204	}
	205
	206	static int platform_suspend_begin(suspend_state_t state)
	207	{
	208	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->begin)
	209	return freeze_ops->begin();
	210	else if (suspend_ops->begin)
	211	return suspend_ops->begin(state);
	212	else
	213	return 0;
	214	}
	215
ebc3e41e	216	static void platform_resume_end(suspend_state_t state)
8490fdf9 RW	217	{
	218	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
	219	freeze_ops->end();
	220	else if (suspend_ops->end)
	221	suspend_ops->end();
	222	}
	223
ebc3e41e	224	static void platform_recover(suspend_state_t state)
8490fdf9 RW	225	{
	226	if (state != PM_SUSPEND_FREEZE && suspend_ops->recover)
	227	suspend_ops->recover();
	228	}
	229
	230	static bool platform_suspend_again(suspend_state_t state)
	231	{
	232	return state != PM_SUSPEND_FREEZE && suspend_ops->suspend_again ?
	233	suspend_ops->suspend_again() : false;
	234	}
	235
a9d70523 RW	236	static int suspend_test(int level)
	237	{
	238	#ifdef CONFIG_PM_DEBUG
	239	if (pm_test_level == level) {
	240	printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n");
	241	mdelay(5000);
	242	return 1;
	243	}
	244	#endif /* !CONFIG_PM_DEBUG */
	245	return 0;
	246	}
	247
	248	/**
55ae4519	249	* suspend_prepare - Prepare for entering system sleep state.
a9d70523	250	*
55ae4519 RW	251	* Common code run for every system sleep state that can be entered (except for
	252	* hibernation). Run suspend notifiers, allocate the "suspend" console and
	253	* freeze processes.
a9d70523	254	*/
7e73c5ae	255	static int suspend_prepare(suspend_state_t state)
a9d70523 RW	256	{
	257	int error;
	258
8490fdf9	259	if (!sleep_state_supported(state))
a9d70523 RW	260	return -EPERM;
	261
	262	pm_prepare_console();
	263
	264	error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
	265	if (error)
	266	goto Finish;
	267
bb3632c6	268	trace_suspend_resume(TPS("freeze_processes"), 0, true);
a9d70523	269	error = suspend_freeze_processes();
bb3632c6	270	trace_suspend_resume(TPS("freeze_processes"), 0, false);
03afed8b	271	if (!error)
a9d70523 RW	272	return 0;
a9d70523 RW	273
03afed8b TH	274	suspend_stats.failed_freeze++;
03afed8b TH	275	dpm_save_failed_step(SUSPEND_FREEZE);
a9d70523 RW	276	Finish:
	277	pm_notifier_call_chain(PM_POST_SUSPEND);
	278	pm_restore_console();
	279	return error;
	280	}
	281
	282	/* default implementation */
52f5684c	283	void __weak arch_suspend_disable_irqs(void)
a9d70523 RW	284	{
	285	local_irq_disable();
	286	}
	287
	288	/* default implementation */
52f5684c	289	void __weak arch_suspend_enable_irqs(void)
a9d70523 RW	290	{
	291	local_irq_enable();
	292	}
	293
	294	/**
55ae4519 RW	295	* suspend_enter - Make the system enter the given sleep state.
	296	* @state: System sleep state to enter.
	297	* @wakeup: Returns information that the sleep state should not be re-entered.
a9d70523	298	*
3b5fe852	299	* This function should be called after devices have been suspended.
a9d70523	300	*/
3b5fe852	301	static int suspend_enter(suspend_state_t state, bool *wakeup)
a9d70523 RW	302	{
	303	int error;
	304
8490fdf9 RW	305	error = platform_suspend_prepare(state);
	306	if (error)
	307	goto Platform_finish;
a9d70523	308
2a8a8ce6	309	error = dpm_suspend_late(PMSG_SUSPEND);
a9d70523	310	if (error) {
2a8a8ce6	311	printk(KERN_ERR "PM: late suspend of devices failed\n");
ce441011	312	goto Platform_finish;
a9d70523	313	}
a8d46b9e RW	314	error = platform_suspend_prepare_late(state);
	315	if (error)
	316	goto Devices_early_resume;
	317
2a8a8ce6 RW	318	error = dpm_suspend_noirq(PMSG_SUSPEND);
	319	if (error) {
	320	printk(KERN_ERR "PM: noirq suspend of devices failed\n");
a8d46b9e	321	goto Platform_early_resume;
2a8a8ce6	322	}
ebc3e41e	323	error = platform_suspend_prepare_noirq(state);
8490fdf9 RW	324	if (error)
8490fdf9 RW	325	goto Platform_wake;
a9d70523	326
08605acc ZR	327	if (suspend_test(TEST_PLATFORM))
	328	goto Platform_wake;
	329
7e73c5ae ZR	330	/*
	331	* PM_SUSPEND_FREEZE equals
	332	* frozen processes + suspended devices + idle processors.
	333	* Thus we should invoke freeze_enter() soon after
	334	* all the devices are suspended.
	335	*/
	336	if (state == PM_SUSPEND_FREEZE) {
bb3632c6	337	trace_suspend_resume(TPS("machine_suspend"), state, true);
7e73c5ae	338	freeze_enter();
bb3632c6	339	trace_suspend_resume(TPS("machine_suspend"), state, false);
7e73c5ae ZR	340	goto Platform_wake;
	341	}
	342
a9d70523 RW	343	error = disable_nonboot_cpus();
	344	if (error \|\| suspend_test(TEST_CPUS))
	345	goto Enable_cpus;
	346
	347	arch_suspend_disable_irqs();
	348	BUG_ON(!irqs_disabled());
	349
2e711c04	350	error = syscore_suspend();
a9d70523	351	if (!error) {
3b5fe852 MH	352	*wakeup = pm_wakeup_pending();
3b5fe852 MH	353	if (!(suspend_test(TEST_CORE) \|\| *wakeup)) {
bb3632c6 TB	354	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	355	state, true);
a9d70523	356	error = suspend_ops->enter(state);
bb3632c6 TB	357	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	358	state, false);
c125e96f RW	359	events_check_enabled = false;
c125e96f RW	360	}
40dc166c	361	syscore_resume();
a9d70523 RW	362	}
	363
	364	arch_suspend_enable_irqs();
	365	BUG_ON(irqs_disabled());
	366
	367	Enable_cpus:
	368	enable_nonboot_cpus();
	369
	370	Platform_wake:
ebc3e41e	371	platform_resume_noirq(state);
2a8a8ce6 RW	372	dpm_resume_noirq(PMSG_RESUME);
2a8a8ce6 RW	373
a8d46b9e RW	374	Platform_early_resume:
	375	platform_resume_early(state);
	376
2a8a8ce6 RW	377	Devices_early_resume:
2a8a8ce6 RW	378	dpm_resume_early(PMSG_RESUME);
a9d70523	379
ce441011	380	Platform_finish:
ebc3e41e	381	platform_resume_finish(state);
a9d70523 RW	382	return error;
	383	}
	384
	385	/**
55ae4519 RW	386	* suspend_devices_and_enter - Suspend devices and enter system sleep state.
55ae4519 RW	387	* @state: System sleep state to enter.
a9d70523 RW	388	*/
	389	int suspend_devices_and_enter(suspend_state_t state)
	390	{
	391	int error;
3b5fe852	392	bool wakeup = false;
a9d70523	393
8490fdf9	394	if (!sleep_state_supported(state))
a9d70523 RW	395	return -ENOSYS;
a9d70523 RW	396
8490fdf9 RW	397	error = platform_suspend_begin(state);
	398	if (error)
	399	goto Close;
	400
a9d70523 RW	401	suspend_console();
	402	suspend_test_start();
	403	error = dpm_suspend_start(PMSG_SUSPEND);
	404	if (error) {
9350de06	405	pr_err("PM: Some devices failed to suspend, or early wake event detected\n");
a9d70523 RW	406	goto Recover_platform;
	407	}
	408	suspend_test_finish("suspend devices");
	409	if (suspend_test(TEST_DEVICES))
	410	goto Recover_platform;
	411
3b5fe852 MH	412	do {
3b5fe852 MH	413	error = suspend_enter(state, &wakeup);
8490fdf9	414	} while (!error && !wakeup && platform_suspend_again(state));
a9d70523 RW	415
	416	Resume_devices:
	417	suspend_test_start();
	418	dpm_resume_end(PMSG_RESUME);
	419	suspend_test_finish("resume devices");
0cadc702	420	trace_suspend_resume(TPS("resume_console"), state, true);
a9d70523	421	resume_console();
0cadc702	422	trace_suspend_resume(TPS("resume_console"), state, false);
1f0b6386	423
8490fdf9	424	Close:
ebc3e41e	425	platform_resume_end(state);
a9d70523 RW	426	return error;
	427
	428	Recover_platform:
ebc3e41e	429	platform_recover(state);
a9d70523 RW	430	goto Resume_devices;
	431	}
	432
	433	/**
55ae4519	434	* suspend_finish - Clean up before finishing the suspend sequence.
a9d70523	435	*
55ae4519 RW	436	* Call platform code to clean up, restart processes, and free the console that
55ae4519 RW	437	* we've allocated. This routine is not called for hibernation.
a9d70523 RW	438	*/
	439	static void suspend_finish(void)
	440	{
	441	suspend_thaw_processes();
a9d70523 RW	442	pm_notifier_call_chain(PM_POST_SUSPEND);
	443	pm_restore_console();
	444	}
	445
	446	/**
55ae4519 RW	447	* enter_state - Do common work needed to enter system sleep state.
55ae4519 RW	448	* @state: System sleep state to enter.
a9d70523	449	*
55ae4519 RW	450	* Make sure that no one else is trying to put the system into a sleep state.
	451	* Fail if that's not the case. Otherwise, prepare for system suspend, make the
	452	* system enter the given sleep state and clean up after wakeup.
a9d70523	453	*/
93e1ee43	454	static int enter_state(suspend_state_t state)
a9d70523 RW	455	{
	456	int error;
	457
bb3632c6	458	trace_suspend_resume(TPS("suspend_enter"), state, true);
43e8317b RW	459	if (state == PM_SUSPEND_FREEZE) {
	460	#ifdef CONFIG_PM_DEBUG
	461	if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
	462	pr_warning("PM: Unsupported test mode for freeze state,"
	463	"please choose none/freezer/devices/platform.\n");
	464	return -EAGAIN;
	465	}
	466	#endif
	467	} else if (!valid_state(state)) {
	468	return -EINVAL;
	469	}
a9d70523 RW	470	if (!mutex_trylock(&pm_mutex))
	471	return -EBUSY;
	472
7e73c5ae ZR	473	if (state == PM_SUSPEND_FREEZE)
	474	freeze_begin();
	475
bb3632c6	476	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
a9d70523 RW	477	printk(KERN_INFO "PM: Syncing filesystems ... ");
	478	sys_sync();
	479	printk("done.\n");
bb3632c6	480	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
a9d70523	481
d431cbc5	482	pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]);
7e73c5ae	483	error = suspend_prepare(state);
a9d70523 RW	484	if (error)
	485	goto Unlock;
	486
	487	if (suspend_test(TEST_FREEZER))
	488	goto Finish;
	489
bb3632c6	490	trace_suspend_resume(TPS("suspend_enter"), state, false);
d431cbc5	491	pr_debug("PM: Entering %s sleep\n", pm_states[state]);
87186475	492	pm_restrict_gfp_mask();
a9d70523	493	error = suspend_devices_and_enter(state);
87186475	494	pm_restore_gfp_mask();
a9d70523 RW	495
	496	Finish:
	497	pr_debug("PM: Finishing wakeup.\n");
	498	suspend_finish();
	499	Unlock:
	500	mutex_unlock(&pm_mutex);
	501	return error;
	502	}
	503
	504	/**
55ae4519 RW	505	* pm_suspend - Externally visible function for suspending the system.
55ae4519 RW	506	* @state: System sleep state to enter.
a9d70523	507	*
55ae4519 RW	508	* Check if the value of @state represents one of the supported states,
55ae4519 RW	509	* execute enter_state() and update system suspend statistics.
a9d70523 RW	510	*/
	511	int pm_suspend(suspend_state_t state)
	512	{
bc25cf50 RW	513	int error;
	514
	515	if (state <= PM_SUSPEND_ON \|\| state >= PM_SUSPEND_MAX)
	516	return -EINVAL;
	517
	518	error = enter_state(state);
	519	if (error) {
	520	suspend_stats.fail++;
	521	dpm_save_failed_errno(error);
	522	} else {
	523	suspend_stats.success++;
2a77c46d	524	}
bc25cf50	525	return error;
a9d70523 RW	526	}
a9d70523 RW	527	EXPORT_SYMBOL(pm_suspend);