[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 <linux/moduleparam.h>

#include "power.h"

const char * const pm_labels[] = {
	[PM_SUSPEND_FREEZE] = "freeze",
	[PM_SUSPEND_STANDBY] = "standby",
	[PM_SUSPEND_MEM] = "mem",
};
const char *pm_states[PM_SUSPEND_MAX];
static const char * const mem_sleep_labels[] = {
	[PM_SUSPEND_FREEZE] = "s2idle",
	[PM_SUSPEND_STANDBY] = "shallow",
	[PM_SUSPEND_MEM] = "deep",
};
const char *mem_sleep_states[PM_SUSPEND_MAX];

suspend_state_t mem_sleep_current = PM_SUSPEND_FREEZE;
static suspend_state_t mem_sleep_default = PM_SUSPEND_MEM;

unsigned int pm_suspend_global_flags;
EXPORT_SYMBOL_GPL(pm_suspend_global_flags);

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)
{
	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, true);

	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();
	/* 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);

	cpuidle_pause();
	put_online_cpus();

	spin_lock_irq(&suspend_freeze_lock);

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

	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, false);
}

static void s2idle_loop(void)
{
	pr_debug("PM: suspend-to-idle\n");

	do {
		freeze_enter();

		if (freeze_ops && freeze_ops->wake)
			freeze_ops->wake();

		dpm_resume_noirq(PMSG_RESUME);
		if (freeze_ops && freeze_ops->sync)
			freeze_ops->sync();

		if (pm_wakeup_pending())
			break;

		pm_wakeup_clear(false);
	} while (!dpm_suspend_noirq(PMSG_SUSPEND));

	pr_debug("PM: resume from suspend-to-idle\n");
}

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);
}

void __init pm_states_init(void)
{
	/* "mem" and "freeze" are always present in /sys/power/state. */
	pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
	pm_states[PM_SUSPEND_FREEZE] = pm_labels[PM_SUSPEND_FREEZE];
	/*
	 * Suspend-to-idle should be supported even without any suspend_ops,
	 * initialize mem_sleep_states[] accordingly here.
	 */
	mem_sleep_states[PM_SUSPEND_FREEZE] = mem_sleep_labels[PM_SUSPEND_FREEZE];
}

static int __init mem_sleep_default_setup(char *str)
{
	suspend_state_t state;

	for (state = PM_SUSPEND_FREEZE; state <= PM_SUSPEND_MEM; state++)
		if (mem_sleep_labels[state] &&
		    !strcmp(str, mem_sleep_labels[state])) {
			mem_sleep_default = state;
			break;
		}

	return 1;
}
__setup("mem_sleep_default=", mem_sleep_default_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)
{
	lock_system_sleep();

	suspend_ops = ops;

	if (valid_state(PM_SUSPEND_STANDBY)) {
		mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY];
		pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY];
		if (mem_sleep_default == PM_SUSPEND_STANDBY)
			mem_sleep_current = PM_SUSPEND_STANDBY;
	}
	if (valid_state(PM_SUSPEND_MEM)) {
		mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
		if (mem_sleep_default == PM_SUSPEND_MEM)
			mem_sleep_current = PM_SUSPEND_MEM;
	}

	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 && 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 && 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;
}

#ifdef CONFIG_PM_DEBUG
static unsigned int pm_test_delay = 5;
module_param(pm_test_delay, uint, 0644);
MODULE_PARM_DESC(pm_test_delay,
		 "Number of seconds to wait before resuming from suspend test");
#endif

static int suspend_test(int level)
{
#ifdef CONFIG_PM_DEBUG
	if (pm_test_level == level) {
		pr_info("suspend debug: Waiting for %d second(s).\n",
				pm_test_delay);
		mdelay(pm_test_delay * 1000);
		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, nr_calls = 0;

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

	pm_prepare_console();

	error = __pm_notifier_call_chain(PM_SUSPEND_PREPARE, -1, &nr_calls);
	if (error) {
		nr_calls--;
		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, nr_calls, NULL);
	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) {
		pr_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) {
		pr_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) {
		s2idle_loop();
		goto Platform_early_resume;
	}

	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;
		} else if (*wakeup) {
			error = -EBUSY;
		}
		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_warn("PM: Unsupported test mode for suspend to idle, 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();

#ifndef CONFIG_SUSPEND_SKIP_SYNC
	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
	pr_info("PM: Syncing filesystems ... ");
	sys_sync();
	pr_cont("done.\n");
	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
#endif

	pr_debug("PM: Preparing system for sleep (%s)\n", pm_states[state]);
	pm_suspend_clear_flags();
	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: Suspending system (%s)\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>
1d4a9c17	31	#include <linux/moduleparam.h>
a9d70523 RW	32
	33	#include "power.h"
	34
406e7938 RW	35	const char * const pm_labels[] = {
	36	[PM_SUSPEND_FREEZE] = "freeze",
	37	[PM_SUSPEND_STANDBY] = "standby",
	38	[PM_SUSPEND_MEM] = "mem",
	39	};
d431cbc5	40	const char *pm_states[PM_SUSPEND_MAX];
406e7938 RW	41	static const char * const mem_sleep_labels[] = {
	42	[PM_SUSPEND_FREEZE] = "s2idle",
	43	[PM_SUSPEND_STANDBY] = "shallow",
	44	[PM_SUSPEND_MEM] = "deep",
	45	};
	46	const char *mem_sleep_states[PM_SUSPEND_MAX];
	47
	48	suspend_state_t mem_sleep_current = PM_SUSPEND_FREEZE;
e326ce01	49	static suspend_state_t mem_sleep_default = PM_SUSPEND_MEM;
a9d70523	50
ef25ba04 RW	51	unsigned int pm_suspend_global_flags;
	52	EXPORT_SYMBOL_GPL(pm_suspend_global_flags);
	53
2f55ac07	54	static const struct platform_suspend_ops *suspend_ops;
1f0b6386	55	static const struct platform_freeze_ops *freeze_ops;
7e73c5ae	56	static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head);
38106313 RW	57
	58	enum freeze_state __read_mostly suspend_freeze_state;
	59	static DEFINE_SPINLOCK(suspend_freeze_lock);
7e73c5ae	60
1f0b6386 RW	61	void freeze_set_ops(const struct platform_freeze_ops *ops)
	62	{
	63	lock_system_sleep();
	64	freeze_ops = ops;
	65	unlock_system_sleep();
	66	}
	67
7e73c5ae ZR	68	static void freeze_begin(void)
7e73c5ae ZR	69	{
38106313	70	suspend_freeze_state = FREEZE_STATE_NONE;
7e73c5ae ZR	71	}
	72
	73	static void freeze_enter(void)
	74	{
33e4f80e RW	75	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, true);
33e4f80e RW	76
38106313 RW	77	spin_lock_irq(&suspend_freeze_lock);
	78	if (pm_wakeup_pending())
	79	goto out;
	80
	81	suspend_freeze_state = FREEZE_STATE_ENTER;
	82	spin_unlock_irq(&suspend_freeze_lock);
	83
	84	get_online_cpus();
f3f12532	85	cpuidle_resume();
38106313 RW	86
	87	/* Push all the CPUs into the idle loop. */
	88	wake_up_all_idle_cpus();
38106313 RW	89	/* Make the current CPU wait so it can enter the idle loop too. */
	90	wait_event(suspend_freeze_wait_head,
	91	suspend_freeze_state == FREEZE_STATE_WAKE);
38106313	92
f3f12532	93	cpuidle_pause();
38106313 RW	94	put_online_cpus();
	95
	96	spin_lock_irq(&suspend_freeze_lock);
	97
	98	out:
	99	suspend_freeze_state = FREEZE_STATE_NONE;
	100	spin_unlock_irq(&suspend_freeze_lock);
33e4f80e RW	101
	102	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, false);
	103	}
	104
	105	static void s2idle_loop(void)
	106	{
	107	pr_debug("PM: suspend-to-idle\n");
	108
	109	do {
	110	freeze_enter();
	111
	112	if (freeze_ops && freeze_ops->wake)
	113	freeze_ops->wake();
	114
	115	dpm_resume_noirq(PMSG_RESUME);
	116	if (freeze_ops && freeze_ops->sync)
	117	freeze_ops->sync();
	118
	119	if (pm_wakeup_pending())
	120	break;
	121
	122	pm_wakeup_clear(false);
	123	} while (!dpm_suspend_noirq(PMSG_SUSPEND));
	124
	125	pr_debug("PM: resume from suspend-to-idle\n");
7e73c5ae ZR	126	}
	127
	128	void freeze_wake(void)
	129	{
38106313 RW	130	unsigned long flags;
	131
	132	spin_lock_irqsave(&suspend_freeze_lock, flags);
	133	if (suspend_freeze_state > FREEZE_STATE_NONE) {
	134	suspend_freeze_state = FREEZE_STATE_WAKE;
	135	wake_up(&suspend_freeze_wait_head);
	136	}
	137	spin_unlock_irqrestore(&suspend_freeze_lock, flags);
7e73c5ae ZR	138	}
	139	EXPORT_SYMBOL_GPL(freeze_wake);
	140
43e8317b RW	141	static bool valid_state(suspend_state_t state)
	142	{
	143	/*
	144	* PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
	145	* support and need to be valid to the low level
	146	* implementation, no valid callback implies that none are valid.
	147	*/
	148	return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
	149	}
	150
fa7fd6fa SH	151	void __init pm_states_init(void)
fa7fd6fa SH	152	{
406e7938 RW	153	/* "mem" and "freeze" are always present in /sys/power/state. */
	154	pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
	155	pm_states[PM_SUSPEND_FREEZE] = pm_labels[PM_SUSPEND_FREEZE];
fa7fd6fa	156	/*
406e7938 RW	157	* Suspend-to-idle should be supported even without any suspend_ops,
406e7938 RW	158	* initialize mem_sleep_states[] accordingly here.
fa7fd6fa	159	*/
406e7938	160	mem_sleep_states[PM_SUSPEND_FREEZE] = mem_sleep_labels[PM_SUSPEND_FREEZE];
fa7fd6fa SH	161	}
fa7fd6fa SH	162
406e7938	163	static int __init mem_sleep_default_setup(char *str)
0399d4db	164	{
406e7938 RW	165	suspend_state_t state;
	166
	167	for (state = PM_SUSPEND_FREEZE; state <= PM_SUSPEND_MEM; state++)
	168	if (mem_sleep_labels[state] &&
	169	!strcmp(str, mem_sleep_labels[state])) {
	170	mem_sleep_default = state;
	171	break;
	172	}
	173
0399d4db RW	174	return 1;
0399d4db RW	175	}
406e7938	176	__setup("mem_sleep_default=", mem_sleep_default_setup);
0399d4db	177
a9d70523	178	/**
55ae4519 RW	179	* suspend_set_ops - Set the global suspend method table.
55ae4519 RW	180	* @ops: Suspend operations to use.
a9d70523	181	*/
2f55ac07	182	void suspend_set_ops(const struct platform_suspend_ops *ops)
a9d70523	183	{
bcda53fa	184	lock_system_sleep();
43e8317b	185
a9d70523	186	suspend_ops = ops;
0399d4db	187
406e7938 RW	188	if (valid_state(PM_SUSPEND_STANDBY)) {
	189	mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY];
	190	pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY];
	191	if (mem_sleep_default == PM_SUSPEND_STANDBY)
	192	mem_sleep_current = PM_SUSPEND_STANDBY;
	193	}
	194	if (valid_state(PM_SUSPEND_MEM)) {
	195	mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
e326ce01	196	if (mem_sleep_default == PM_SUSPEND_MEM)
406e7938 RW	197	mem_sleep_current = PM_SUSPEND_MEM;
406e7938 RW	198	}
43e8317b	199
bcda53fa	200	unlock_system_sleep();
a9d70523	201	}
a5e4fd87	202	EXPORT_SYMBOL_GPL(suspend_set_ops);
a9d70523	203
a9d70523	204	/**
55ae4519	205	* suspend_valid_only_mem - Generic memory-only valid callback.
a9d70523	206	*
55ae4519 RW	207	* Platform drivers that implement mem suspend only and only need to check for
	208	* that in their .valid() callback can use this instead of rolling their own
	209	* .valid() callback.
a9d70523 RW	210	*/
	211	int suspend_valid_only_mem(suspend_state_t state)
	212	{
	213	return state == PM_SUSPEND_MEM;
	214	}
a5e4fd87	215	EXPORT_SYMBOL_GPL(suspend_valid_only_mem);
a9d70523	216
8490fdf9 RW	217	static bool sleep_state_supported(suspend_state_t state)
	218	{
	219	return state == PM_SUSPEND_FREEZE \|\| (suspend_ops && suspend_ops->enter);
	220	}
	221
	222	static int platform_suspend_prepare(suspend_state_t state)
	223	{
	224	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare ?
	225	suspend_ops->prepare() : 0;
	226	}
	227
a8d46b9e RW	228	static int platform_suspend_prepare_late(suspend_state_t state)
a8d46b9e RW	229	{
403b9636	230	return state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->prepare ?
a8d46b9e RW	231	freeze_ops->prepare() : 0;
	232	}
	233
ebc3e41e	234	static int platform_suspend_prepare_noirq(suspend_state_t state)
8490fdf9 RW	235	{
	236	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare_late ?
	237	suspend_ops->prepare_late() : 0;
	238	}
	239
ebc3e41e	240	static void platform_resume_noirq(suspend_state_t state)
8490fdf9 RW	241	{
	242	if (state != PM_SUSPEND_FREEZE && suspend_ops->wake)
	243	suspend_ops->wake();
	244	}
	245
a8d46b9e RW	246	static void platform_resume_early(suspend_state_t state)
a8d46b9e RW	247	{
403b9636	248	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->restore)
a8d46b9e RW	249	freeze_ops->restore();
	250	}
	251
ebc3e41e	252	static void platform_resume_finish(suspend_state_t state)
8490fdf9 RW	253	{
	254	if (state != PM_SUSPEND_FREEZE && suspend_ops->finish)
	255	suspend_ops->finish();
	256	}
	257
	258	static int platform_suspend_begin(suspend_state_t state)
	259	{
	260	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->begin)
	261	return freeze_ops->begin();
fa7fd6fa	262	else if (suspend_ops && suspend_ops->begin)
8490fdf9 RW	263	return suspend_ops->begin(state);
	264	else
	265	return 0;
	266	}
	267
ebc3e41e	268	static void platform_resume_end(suspend_state_t state)
8490fdf9 RW	269	{
	270	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
	271	freeze_ops->end();
fa7fd6fa	272	else if (suspend_ops && suspend_ops->end)
8490fdf9 RW	273	suspend_ops->end();
	274	}
	275
ebc3e41e	276	static void platform_recover(suspend_state_t state)
8490fdf9 RW	277	{
	278	if (state != PM_SUSPEND_FREEZE && suspend_ops->recover)
	279	suspend_ops->recover();
	280	}
	281
	282	static bool platform_suspend_again(suspend_state_t state)
	283	{
	284	return state != PM_SUSPEND_FREEZE && suspend_ops->suspend_again ?
	285	suspend_ops->suspend_again() : false;
	286	}
	287
1d4a9c17 BN	288	#ifdef CONFIG_PM_DEBUG
	289	static unsigned int pm_test_delay = 5;
	290	module_param(pm_test_delay, uint, 0644);
	291	MODULE_PARM_DESC(pm_test_delay,
	292	"Number of seconds to wait before resuming from suspend test");
	293	#endif
	294
a9d70523 RW	295	static int suspend_test(int level)
	296	{
	297	#ifdef CONFIG_PM_DEBUG
	298	if (pm_test_level == level) {
22e09b33	299	pr_info("suspend debug: Waiting for %d second(s).\n",
1d4a9c17 BN	300	pm_test_delay);
1d4a9c17 BN	301	mdelay(pm_test_delay * 1000);
a9d70523 RW	302	return 1;
	303	}
	304	#endif /* !CONFIG_PM_DEBUG */
	305	return 0;
	306	}
	307
	308	/**
55ae4519	309	* suspend_prepare - Prepare for entering system sleep state.
a9d70523	310	*
55ae4519 RW	311	* Common code run for every system sleep state that can be entered (except for
	312	* hibernation). Run suspend notifiers, allocate the "suspend" console and
	313	* freeze processes.
a9d70523	314	*/
7e73c5ae	315	static int suspend_prepare(suspend_state_t state)
a9d70523	316	{
ea00f4f4	317	int error, nr_calls = 0;
a9d70523	318
8490fdf9	319	if (!sleep_state_supported(state))
a9d70523 RW	320	return -EPERM;
	321
	322	pm_prepare_console();
	323
ea00f4f4 LW	324	error = __pm_notifier_call_chain(PM_SUSPEND_PREPARE, -1, &nr_calls);
	325	if (error) {
	326	nr_calls--;
a9d70523	327	goto Finish;
ea00f4f4	328	}
a9d70523	329
bb3632c6	330	trace_suspend_resume(TPS("freeze_processes"), 0, true);
a9d70523	331	error = suspend_freeze_processes();
bb3632c6	332	trace_suspend_resume(TPS("freeze_processes"), 0, false);
03afed8b	333	if (!error)
a9d70523 RW	334	return 0;
a9d70523 RW	335
03afed8b TH	336	suspend_stats.failed_freeze++;
03afed8b TH	337	dpm_save_failed_step(SUSPEND_FREEZE);
a9d70523	338	Finish:
ea00f4f4	339	__pm_notifier_call_chain(PM_POST_SUSPEND, nr_calls, NULL);
a9d70523 RW	340	pm_restore_console();
	341	return error;
	342	}
	343
	344	/* default implementation */
52f5684c	345	void __weak arch_suspend_disable_irqs(void)
a9d70523 RW	346	{
	347	local_irq_disable();
	348	}
	349
	350	/* default implementation */
52f5684c	351	void __weak arch_suspend_enable_irqs(void)
a9d70523 RW	352	{
	353	local_irq_enable();
	354	}
	355
	356	/**
55ae4519 RW	357	* suspend_enter - Make the system enter the given sleep state.
	358	* @state: System sleep state to enter.
	359	* @wakeup: Returns information that the sleep state should not be re-entered.
a9d70523	360	*
3b5fe852	361	* This function should be called after devices have been suspended.
a9d70523	362	*/
3b5fe852	363	static int suspend_enter(suspend_state_t state, bool *wakeup)
a9d70523 RW	364	{
	365	int error;
	366
8490fdf9 RW	367	error = platform_suspend_prepare(state);
	368	if (error)
	369	goto Platform_finish;
a9d70523	370
2a8a8ce6	371	error = dpm_suspend_late(PMSG_SUSPEND);
a9d70523	372	if (error) {
22e09b33	373	pr_err("PM: late suspend of devices failed\n");
ce441011	374	goto Platform_finish;
a9d70523	375	}
a8d46b9e RW	376	error = platform_suspend_prepare_late(state);
	377	if (error)
	378	goto Devices_early_resume;
	379
2a8a8ce6 RW	380	error = dpm_suspend_noirq(PMSG_SUSPEND);
2a8a8ce6 RW	381	if (error) {
22e09b33	382	pr_err("PM: noirq suspend of devices failed\n");
a8d46b9e	383	goto Platform_early_resume;
2a8a8ce6	384	}
ebc3e41e	385	error = platform_suspend_prepare_noirq(state);
8490fdf9 RW	386	if (error)
8490fdf9 RW	387	goto Platform_wake;
a9d70523	388
08605acc ZR	389	if (suspend_test(TEST_PLATFORM))
	390	goto Platform_wake;
	391
7e73c5ae ZR	392	/*
	393	* PM_SUSPEND_FREEZE equals
	394	* frozen processes + suspended devices + idle processors.
	395	* Thus we should invoke freeze_enter() soon after
	396	* all the devices are suspended.
	397	*/
	398	if (state == PM_SUSPEND_FREEZE) {
33e4f80e RW	399	s2idle_loop();
33e4f80e RW	400	goto Platform_early_resume;
7e73c5ae ZR	401	}
7e73c5ae ZR	402
a9d70523 RW	403	error = disable_nonboot_cpus();
	404	if (error \|\| suspend_test(TEST_CPUS))
	405	goto Enable_cpus;
	406
	407	arch_suspend_disable_irqs();
	408	BUG_ON(!irqs_disabled());
	409
2e711c04	410	error = syscore_suspend();
a9d70523	411	if (!error) {
3b5fe852 MH	412	*wakeup = pm_wakeup_pending();
3b5fe852 MH	413	if (!(suspend_test(TEST_CORE) \|\| *wakeup)) {
bb3632c6 TB	414	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	415	state, true);
a9d70523	416	error = suspend_ops->enter(state);
bb3632c6 TB	417	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	418	state, false);
c125e96f	419	events_check_enabled = false;
67176736 RK	420	} else if (*wakeup) {
67176736 RK	421	error = -EBUSY;
c125e96f	422	}
40dc166c	423	syscore_resume();
a9d70523 RW	424	}
	425
	426	arch_suspend_enable_irqs();
	427	BUG_ON(irqs_disabled());
	428
	429	Enable_cpus:
	430	enable_nonboot_cpus();
	431
	432	Platform_wake:
ebc3e41e	433	platform_resume_noirq(state);
2a8a8ce6 RW	434	dpm_resume_noirq(PMSG_RESUME);
2a8a8ce6 RW	435
a8d46b9e RW	436	Platform_early_resume:
	437	platform_resume_early(state);
	438
2a8a8ce6 RW	439	Devices_early_resume:
2a8a8ce6 RW	440	dpm_resume_early(PMSG_RESUME);
a9d70523	441
ce441011	442	Platform_finish:
ebc3e41e	443	platform_resume_finish(state);
a9d70523 RW	444	return error;
	445	}
	446
	447	/**
55ae4519 RW	448	* suspend_devices_and_enter - Suspend devices and enter system sleep state.
55ae4519 RW	449	* @state: System sleep state to enter.
a9d70523 RW	450	*/
	451	int suspend_devices_and_enter(suspend_state_t state)
	452	{
	453	int error;
3b5fe852	454	bool wakeup = false;
a9d70523	455
8490fdf9	456	if (!sleep_state_supported(state))
a9d70523 RW	457	return -ENOSYS;
a9d70523 RW	458
8490fdf9 RW	459	error = platform_suspend_begin(state);
	460	if (error)
	461	goto Close;
	462
a9d70523 RW	463	suspend_console();
	464	suspend_test_start();
	465	error = dpm_suspend_start(PMSG_SUSPEND);
	466	if (error) {
9350de06	467	pr_err("PM: Some devices failed to suspend, or early wake event detected\n");
a9d70523 RW	468	goto Recover_platform;
	469	}
	470	suspend_test_finish("suspend devices");
	471	if (suspend_test(TEST_DEVICES))
	472	goto Recover_platform;
	473
3b5fe852 MH	474	do {
3b5fe852 MH	475	error = suspend_enter(state, &wakeup);
8490fdf9	476	} while (!error && !wakeup && platform_suspend_again(state));
a9d70523 RW	477
	478	Resume_devices:
	479	suspend_test_start();
	480	dpm_resume_end(PMSG_RESUME);
	481	suspend_test_finish("resume devices");
0cadc702	482	trace_suspend_resume(TPS("resume_console"), state, true);
a9d70523	483	resume_console();
0cadc702	484	trace_suspend_resume(TPS("resume_console"), state, false);
1f0b6386	485
8490fdf9	486	Close:
ebc3e41e	487	platform_resume_end(state);
a9d70523 RW	488	return error;
	489
	490	Recover_platform:
ebc3e41e	491	platform_recover(state);
a9d70523 RW	492	goto Resume_devices;
	493	}
	494
	495	/**
55ae4519	496	* suspend_finish - Clean up before finishing the suspend sequence.
a9d70523	497	*
55ae4519 RW	498	* Call platform code to clean up, restart processes, and free the console that
55ae4519 RW	499	* we've allocated. This routine is not called for hibernation.
a9d70523 RW	500	*/
	501	static void suspend_finish(void)
	502	{
	503	suspend_thaw_processes();
a9d70523 RW	504	pm_notifier_call_chain(PM_POST_SUSPEND);
	505	pm_restore_console();
	506	}
	507
	508	/**
55ae4519 RW	509	* enter_state - Do common work needed to enter system sleep state.
55ae4519 RW	510	* @state: System sleep state to enter.
a9d70523	511	*
55ae4519 RW	512	* Make sure that no one else is trying to put the system into a sleep state.
	513	* Fail if that's not the case. Otherwise, prepare for system suspend, make the
	514	* system enter the given sleep state and clean up after wakeup.
a9d70523	515	*/
93e1ee43	516	static int enter_state(suspend_state_t state)
a9d70523 RW	517	{
	518	int error;
	519
bb3632c6	520	trace_suspend_resume(TPS("suspend_enter"), state, true);
43e8317b RW	521	if (state == PM_SUSPEND_FREEZE) {
	522	#ifdef CONFIG_PM_DEBUG
	523	if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
a395d6a7	524	pr_warn("PM: Unsupported test mode for suspend to idle, please choose none/freezer/devices/platform.\n");
43e8317b RW	525	return -EAGAIN;
	526	}
	527	#endif
	528	} else if (!valid_state(state)) {
	529	return -EINVAL;
	530	}
a9d70523 RW	531	if (!mutex_trylock(&pm_mutex))
	532	return -EBUSY;
	533
7e73c5ae ZR	534	if (state == PM_SUSPEND_FREEZE)
	535	freeze_begin();
	536
2fd77fff	537	#ifndef CONFIG_SUSPEND_SKIP_SYNC
bb3632c6	538	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
1adb469b	539	pr_info("PM: Syncing filesystems ... ");
a9d70523	540	sys_sync();
1adb469b	541	pr_cont("done.\n");
bb3632c6	542	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
2fd77fff	543	#endif
a9d70523	544
a9215045	545	pr_debug("PM: Preparing system for sleep (%s)\n", pm_states[state]);
ef25ba04	546	pm_suspend_clear_flags();
7e73c5ae	547	error = suspend_prepare(state);
a9d70523 RW	548	if (error)
	549	goto Unlock;
	550
	551	if (suspend_test(TEST_FREEZER))
	552	goto Finish;
	553
bb3632c6	554	trace_suspend_resume(TPS("suspend_enter"), state, false);
a9215045	555	pr_debug("PM: Suspending system (%s)\n", pm_states[state]);
87186475	556	pm_restrict_gfp_mask();
a9d70523	557	error = suspend_devices_and_enter(state);
87186475	558	pm_restore_gfp_mask();
a9d70523 RW	559
	560	Finish:
	561	pr_debug("PM: Finishing wakeup.\n");
	562	suspend_finish();
	563	Unlock:
	564	mutex_unlock(&pm_mutex);
	565	return error;
	566	}
	567
	568	/**
55ae4519 RW	569	* pm_suspend - Externally visible function for suspending the system.
55ae4519 RW	570	* @state: System sleep state to enter.
a9d70523	571	*
55ae4519 RW	572	* Check if the value of @state represents one of the supported states,
55ae4519 RW	573	* execute enter_state() and update system suspend statistics.
a9d70523 RW	574	*/
	575	int pm_suspend(suspend_state_t state)
	576	{
bc25cf50 RW	577	int error;
	578
	579	if (state <= PM_SUSPEND_ON \|\| state >= PM_SUSPEND_MAX)
	580	return -EINVAL;
	581
	582	error = enter_state(state);
	583	if (error) {
	584	suspend_stats.fail++;
	585	dpm_save_failed_errno(error);
	586	} else {
	587	suspend_stats.success++;
2a77c46d	588	}
bc25cf50	589	return error;
a9d70523 RW	590	}
a9d70523 RW	591	EXPORT_SYMBOL(pm_suspend);