[linux-2.6-block.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();
	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);

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

static void s2idle_loop(void)
{
	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));
}

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	{
eed4d47e RW	75	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, true);
eed4d47e 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();
	89	pr_debug("PM: suspend-to-idle\n");
	90	/* Make the current CPU wait so it can enter the idle loop too. */
	91	wait_event(suspend_freeze_wait_head,
	92	suspend_freeze_state == FREEZE_STATE_WAKE);
	93	pr_debug("PM: resume from suspend-to-idle\n");
	94
f3f12532	95	cpuidle_pause();
38106313 RW	96	put_online_cpus();
	97
	98	spin_lock_irq(&suspend_freeze_lock);
	99
	100	out:
	101	suspend_freeze_state = FREEZE_STATE_NONE;
	102	spin_unlock_irq(&suspend_freeze_lock);
eed4d47e RW	103
	104	trace_suspend_resume(TPS("machine_suspend"), PM_SUSPEND_FREEZE, false);
	105	}
	106
	107	static void s2idle_loop(void)
	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));
7e73c5ae ZR	124	}
	125
	126	void freeze_wake(void)
	127	{
38106313 RW	128	unsigned long flags;
	129
	130	spin_lock_irqsave(&suspend_freeze_lock, flags);
	131	if (suspend_freeze_state > FREEZE_STATE_NONE) {
	132	suspend_freeze_state = FREEZE_STATE_WAKE;
	133	wake_up(&suspend_freeze_wait_head);
	134	}
	135	spin_unlock_irqrestore(&suspend_freeze_lock, flags);
7e73c5ae ZR	136	}
	137	EXPORT_SYMBOL_GPL(freeze_wake);
	138
43e8317b RW	139	static bool valid_state(suspend_state_t state)
	140	{
	141	/*
	142	* PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
	143	* support and need to be valid to the low level
	144	* implementation, no valid callback implies that none are valid.
	145	*/
	146	return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
	147	}
	148
fa7fd6fa SH	149	void __init pm_states_init(void)
fa7fd6fa SH	150	{
406e7938 RW	151	/* "mem" and "freeze" are always present in /sys/power/state. */
	152	pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
	153	pm_states[PM_SUSPEND_FREEZE] = pm_labels[PM_SUSPEND_FREEZE];
fa7fd6fa	154	/*
406e7938 RW	155	* Suspend-to-idle should be supported even without any suspend_ops,
406e7938 RW	156	* initialize mem_sleep_states[] accordingly here.
fa7fd6fa	157	*/
406e7938	158	mem_sleep_states[PM_SUSPEND_FREEZE] = mem_sleep_labels[PM_SUSPEND_FREEZE];
fa7fd6fa SH	159	}
fa7fd6fa SH	160
406e7938	161	static int __init mem_sleep_default_setup(char *str)
0399d4db	162	{
406e7938 RW	163	suspend_state_t state;
	164
	165	for (state = PM_SUSPEND_FREEZE; state <= PM_SUSPEND_MEM; state++)
	166	if (mem_sleep_labels[state] &&
	167	!strcmp(str, mem_sleep_labels[state])) {
	168	mem_sleep_default = state;
	169	break;
	170	}
	171
0399d4db RW	172	return 1;
0399d4db RW	173	}
406e7938	174	__setup("mem_sleep_default=", mem_sleep_default_setup);
0399d4db	175
a9d70523	176	/**
55ae4519 RW	177	* suspend_set_ops - Set the global suspend method table.
55ae4519 RW	178	* @ops: Suspend operations to use.
a9d70523	179	*/
2f55ac07	180	void suspend_set_ops(const struct platform_suspend_ops *ops)
a9d70523	181	{
bcda53fa	182	lock_system_sleep();
43e8317b	183
a9d70523	184	suspend_ops = ops;
0399d4db	185
406e7938 RW	186	if (valid_state(PM_SUSPEND_STANDBY)) {
	187	mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY];
	188	pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY];
	189	if (mem_sleep_default == PM_SUSPEND_STANDBY)
	190	mem_sleep_current = PM_SUSPEND_STANDBY;
	191	}
	192	if (valid_state(PM_SUSPEND_MEM)) {
	193	mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
e326ce01	194	if (mem_sleep_default == PM_SUSPEND_MEM)
406e7938 RW	195	mem_sleep_current = PM_SUSPEND_MEM;
406e7938 RW	196	}
43e8317b	197
bcda53fa	198	unlock_system_sleep();
a9d70523	199	}
a5e4fd87	200	EXPORT_SYMBOL_GPL(suspend_set_ops);
a9d70523	201
a9d70523	202	/**
55ae4519	203	* suspend_valid_only_mem - Generic memory-only valid callback.
a9d70523	204	*
55ae4519 RW	205	* Platform drivers that implement mem suspend only and only need to check for
	206	* that in their .valid() callback can use this instead of rolling their own
	207	* .valid() callback.
a9d70523 RW	208	*/
	209	int suspend_valid_only_mem(suspend_state_t state)
	210	{
	211	return state == PM_SUSPEND_MEM;
	212	}
a5e4fd87	213	EXPORT_SYMBOL_GPL(suspend_valid_only_mem);
a9d70523	214
8490fdf9 RW	215	static bool sleep_state_supported(suspend_state_t state)
	216	{
	217	return state == PM_SUSPEND_FREEZE \|\| (suspend_ops && suspend_ops->enter);
	218	}
	219
	220	static int platform_suspend_prepare(suspend_state_t state)
	221	{
	222	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare ?
	223	suspend_ops->prepare() : 0;
	224	}
	225
a8d46b9e RW	226	static int platform_suspend_prepare_late(suspend_state_t state)
a8d46b9e RW	227	{
403b9636	228	return state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->prepare ?
a8d46b9e RW	229	freeze_ops->prepare() : 0;
	230	}
	231
ebc3e41e	232	static int platform_suspend_prepare_noirq(suspend_state_t state)
8490fdf9 RW	233	{
	234	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare_late ?
	235	suspend_ops->prepare_late() : 0;
	236	}
	237
ebc3e41e	238	static void platform_resume_noirq(suspend_state_t state)
8490fdf9 RW	239	{
	240	if (state != PM_SUSPEND_FREEZE && suspend_ops->wake)
	241	suspend_ops->wake();
	242	}
	243
a8d46b9e RW	244	static void platform_resume_early(suspend_state_t state)
a8d46b9e RW	245	{
403b9636	246	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->restore)
a8d46b9e RW	247	freeze_ops->restore();
	248	}
	249
ebc3e41e	250	static void platform_resume_finish(suspend_state_t state)
8490fdf9 RW	251	{
	252	if (state != PM_SUSPEND_FREEZE && suspend_ops->finish)
	253	suspend_ops->finish();
	254	}
	255
	256	static int platform_suspend_begin(suspend_state_t state)
	257	{
	258	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->begin)
	259	return freeze_ops->begin();
fa7fd6fa	260	else if (suspend_ops && suspend_ops->begin)
8490fdf9 RW	261	return suspend_ops->begin(state);
	262	else
	263	return 0;
	264	}
	265
ebc3e41e	266	static void platform_resume_end(suspend_state_t state)
8490fdf9 RW	267	{
	268	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
	269	freeze_ops->end();
fa7fd6fa	270	else if (suspend_ops && suspend_ops->end)
8490fdf9 RW	271	suspend_ops->end();
	272	}
	273
ebc3e41e	274	static void platform_recover(suspend_state_t state)
8490fdf9 RW	275	{
	276	if (state != PM_SUSPEND_FREEZE && suspend_ops->recover)
	277	suspend_ops->recover();
	278	}
	279
	280	static bool platform_suspend_again(suspend_state_t state)
	281	{
	282	return state != PM_SUSPEND_FREEZE && suspend_ops->suspend_again ?
	283	suspend_ops->suspend_again() : false;
	284	}
	285
1d4a9c17 BN	286	#ifdef CONFIG_PM_DEBUG
	287	static unsigned int pm_test_delay = 5;
	288	module_param(pm_test_delay, uint, 0644);
	289	MODULE_PARM_DESC(pm_test_delay,
	290	"Number of seconds to wait before resuming from suspend test");
	291	#endif
	292
a9d70523 RW	293	static int suspend_test(int level)
	294	{
	295	#ifdef CONFIG_PM_DEBUG
	296	if (pm_test_level == level) {
22e09b33	297	pr_info("suspend debug: Waiting for %d second(s).\n",
1d4a9c17 BN	298	pm_test_delay);
1d4a9c17 BN	299	mdelay(pm_test_delay * 1000);
a9d70523 RW	300	return 1;
	301	}
	302	#endif /* !CONFIG_PM_DEBUG */
	303	return 0;
	304	}
	305
	306	/**
55ae4519	307	* suspend_prepare - Prepare for entering system sleep state.
a9d70523	308	*
55ae4519 RW	309	* Common code run for every system sleep state that can be entered (except for
	310	* hibernation). Run suspend notifiers, allocate the "suspend" console and
	311	* freeze processes.
a9d70523	312	*/
7e73c5ae	313	static int suspend_prepare(suspend_state_t state)
a9d70523	314	{
ea00f4f4	315	int error, nr_calls = 0;
a9d70523	316
8490fdf9	317	if (!sleep_state_supported(state))
a9d70523 RW	318	return -EPERM;
	319
	320	pm_prepare_console();
	321
ea00f4f4 LW	322	error = __pm_notifier_call_chain(PM_SUSPEND_PREPARE, -1, &nr_calls);
	323	if (error) {
	324	nr_calls--;
a9d70523	325	goto Finish;
ea00f4f4	326	}
a9d70523	327
bb3632c6	328	trace_suspend_resume(TPS("freeze_processes"), 0, true);
a9d70523	329	error = suspend_freeze_processes();
bb3632c6	330	trace_suspend_resume(TPS("freeze_processes"), 0, false);
03afed8b	331	if (!error)
a9d70523 RW	332	return 0;
a9d70523 RW	333
03afed8b TH	334	suspend_stats.failed_freeze++;
03afed8b TH	335	dpm_save_failed_step(SUSPEND_FREEZE);
a9d70523	336	Finish:
ea00f4f4	337	__pm_notifier_call_chain(PM_POST_SUSPEND, nr_calls, NULL);
a9d70523 RW	338	pm_restore_console();
	339	return error;
	340	}
	341
	342	/* default implementation */
52f5684c	343	void __weak arch_suspend_disable_irqs(void)
a9d70523 RW	344	{
	345	local_irq_disable();
	346	}
	347
	348	/* default implementation */
52f5684c	349	void __weak arch_suspend_enable_irqs(void)
a9d70523 RW	350	{
	351	local_irq_enable();
	352	}
	353
	354	/**
55ae4519 RW	355	* suspend_enter - Make the system enter the given sleep state.
	356	* @state: System sleep state to enter.
	357	* @wakeup: Returns information that the sleep state should not be re-entered.
a9d70523	358	*
3b5fe852	359	* This function should be called after devices have been suspended.
a9d70523	360	*/
3b5fe852	361	static int suspend_enter(suspend_state_t state, bool *wakeup)
a9d70523 RW	362	{
	363	int error;
	364
8490fdf9 RW	365	error = platform_suspend_prepare(state);
	366	if (error)
	367	goto Platform_finish;
a9d70523	368
2a8a8ce6	369	error = dpm_suspend_late(PMSG_SUSPEND);
a9d70523	370	if (error) {
22e09b33	371	pr_err("PM: late suspend of devices failed\n");
ce441011	372	goto Platform_finish;
a9d70523	373	}
a8d46b9e RW	374	error = platform_suspend_prepare_late(state);
	375	if (error)
	376	goto Devices_early_resume;
	377
2a8a8ce6 RW	378	error = dpm_suspend_noirq(PMSG_SUSPEND);
2a8a8ce6 RW	379	if (error) {
22e09b33	380	pr_err("PM: noirq suspend of devices failed\n");
a8d46b9e	381	goto Platform_early_resume;
2a8a8ce6	382	}
ebc3e41e	383	error = platform_suspend_prepare_noirq(state);
8490fdf9 RW	384	if (error)
8490fdf9 RW	385	goto Platform_wake;
a9d70523	386
08605acc ZR	387	if (suspend_test(TEST_PLATFORM))
	388	goto Platform_wake;
	389
7e73c5ae ZR	390	/*
	391	* PM_SUSPEND_FREEZE equals
	392	* frozen processes + suspended devices + idle processors.
	393	* Thus we should invoke freeze_enter() soon after
	394	* all the devices are suspended.
	395	*/
	396	if (state == PM_SUSPEND_FREEZE) {
eed4d47e RW	397	s2idle_loop();
eed4d47e RW	398	goto Platform_early_resume;
7e73c5ae ZR	399	}
7e73c5ae ZR	400
a9d70523 RW	401	error = disable_nonboot_cpus();
	402	if (error \|\| suspend_test(TEST_CPUS))
	403	goto Enable_cpus;
	404
	405	arch_suspend_disable_irqs();
	406	BUG_ON(!irqs_disabled());
	407
2e711c04	408	error = syscore_suspend();
a9d70523	409	if (!error) {
3b5fe852 MH	410	*wakeup = pm_wakeup_pending();
3b5fe852 MH	411	if (!(suspend_test(TEST_CORE) \|\| *wakeup)) {
bb3632c6 TB	412	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	413	state, true);
a9d70523	414	error = suspend_ops->enter(state);
bb3632c6 TB	415	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	416	state, false);
c125e96f	417	events_check_enabled = false;
67176736 RK	418	} else if (*wakeup) {
67176736 RK	419	error = -EBUSY;
c125e96f	420	}
40dc166c	421	syscore_resume();
a9d70523 RW	422	}
	423
	424	arch_suspend_enable_irqs();
	425	BUG_ON(irqs_disabled());
	426
	427	Enable_cpus:
	428	enable_nonboot_cpus();
	429
	430	Platform_wake:
ebc3e41e	431	platform_resume_noirq(state);
2a8a8ce6 RW	432	dpm_resume_noirq(PMSG_RESUME);
2a8a8ce6 RW	433
a8d46b9e RW	434	Platform_early_resume:
	435	platform_resume_early(state);
	436
2a8a8ce6 RW	437	Devices_early_resume:
2a8a8ce6 RW	438	dpm_resume_early(PMSG_RESUME);
a9d70523	439
ce441011	440	Platform_finish:
ebc3e41e	441	platform_resume_finish(state);
a9d70523 RW	442	return error;
	443	}
	444
	445	/**
55ae4519 RW	446	* suspend_devices_and_enter - Suspend devices and enter system sleep state.
55ae4519 RW	447	* @state: System sleep state to enter.
a9d70523 RW	448	*/
	449	int suspend_devices_and_enter(suspend_state_t state)
	450	{
	451	int error;
3b5fe852	452	bool wakeup = false;
a9d70523	453
8490fdf9	454	if (!sleep_state_supported(state))
a9d70523 RW	455	return -ENOSYS;
a9d70523 RW	456
8490fdf9 RW	457	error = platform_suspend_begin(state);
	458	if (error)
	459	goto Close;
	460
a9d70523 RW	461	suspend_console();
	462	suspend_test_start();
	463	error = dpm_suspend_start(PMSG_SUSPEND);
	464	if (error) {
9350de06	465	pr_err("PM: Some devices failed to suspend, or early wake event detected\n");
a9d70523 RW	466	goto Recover_platform;
	467	}
	468	suspend_test_finish("suspend devices");
	469	if (suspend_test(TEST_DEVICES))
	470	goto Recover_platform;
	471
3b5fe852 MH	472	do {
3b5fe852 MH	473	error = suspend_enter(state, &wakeup);
8490fdf9	474	} while (!error && !wakeup && platform_suspend_again(state));
a9d70523 RW	475
	476	Resume_devices:
	477	suspend_test_start();
	478	dpm_resume_end(PMSG_RESUME);
	479	suspend_test_finish("resume devices");
0cadc702	480	trace_suspend_resume(TPS("resume_console"), state, true);
a9d70523	481	resume_console();
0cadc702	482	trace_suspend_resume(TPS("resume_console"), state, false);
1f0b6386	483
8490fdf9	484	Close:
ebc3e41e	485	platform_resume_end(state);
a9d70523 RW	486	return error;
	487
	488	Recover_platform:
ebc3e41e	489	platform_recover(state);
a9d70523 RW	490	goto Resume_devices;
	491	}
	492
	493	/**
55ae4519	494	* suspend_finish - Clean up before finishing the suspend sequence.
a9d70523	495	*
55ae4519 RW	496	* Call platform code to clean up, restart processes, and free the console that
55ae4519 RW	497	* we've allocated. This routine is not called for hibernation.
a9d70523 RW	498	*/
	499	static void suspend_finish(void)
	500	{
	501	suspend_thaw_processes();
a9d70523 RW	502	pm_notifier_call_chain(PM_POST_SUSPEND);
	503	pm_restore_console();
	504	}
	505
	506	/**
55ae4519 RW	507	* enter_state - Do common work needed to enter system sleep state.
55ae4519 RW	508	* @state: System sleep state to enter.
a9d70523	509	*
55ae4519 RW	510	* Make sure that no one else is trying to put the system into a sleep state.
	511	* Fail if that's not the case. Otherwise, prepare for system suspend, make the
	512	* system enter the given sleep state and clean up after wakeup.
a9d70523	513	*/
93e1ee43	514	static int enter_state(suspend_state_t state)
a9d70523 RW	515	{
	516	int error;
	517
bb3632c6	518	trace_suspend_resume(TPS("suspend_enter"), state, true);
43e8317b RW	519	if (state == PM_SUSPEND_FREEZE) {
	520	#ifdef CONFIG_PM_DEBUG
	521	if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
a395d6a7	522	pr_warn("PM: Unsupported test mode for suspend to idle, please choose none/freezer/devices/platform.\n");
43e8317b RW	523	return -EAGAIN;
	524	}
	525	#endif
	526	} else if (!valid_state(state)) {
	527	return -EINVAL;
	528	}
a9d70523 RW	529	if (!mutex_trylock(&pm_mutex))
	530	return -EBUSY;
	531
7e73c5ae ZR	532	if (state == PM_SUSPEND_FREEZE)
	533	freeze_begin();
	534
2fd77fff	535	#ifndef CONFIG_SUSPEND_SKIP_SYNC
bb3632c6	536	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
1adb469b	537	pr_info("PM: Syncing filesystems ... ");
a9d70523	538	sys_sync();
1adb469b	539	pr_cont("done.\n");
bb3632c6	540	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
2fd77fff	541	#endif
a9d70523	542
a9215045	543	pr_debug("PM: Preparing system for sleep (%s)\n", pm_states[state]);
ef25ba04	544	pm_suspend_clear_flags();
7e73c5ae	545	error = suspend_prepare(state);
a9d70523 RW	546	if (error)
	547	goto Unlock;
	548
	549	if (suspend_test(TEST_FREEZER))
	550	goto Finish;
	551
bb3632c6	552	trace_suspend_resume(TPS("suspend_enter"), state, false);
a9215045	553	pr_debug("PM: Suspending system (%s)\n", pm_states[state]);
87186475	554	pm_restrict_gfp_mask();
a9d70523	555	error = suspend_devices_and_enter(state);
87186475	556	pm_restore_gfp_mask();
a9d70523 RW	557
	558	Finish:
	559	pr_debug("PM: Finishing wakeup.\n");
	560	suspend_finish();
	561	Unlock:
	562	mutex_unlock(&pm_mutex);
	563	return error;
	564	}
	565
	566	/**
55ae4519 RW	567	* pm_suspend - Externally visible function for suspending the system.
55ae4519 RW	568	* @state: System sleep state to enter.
a9d70523	569	*
55ae4519 RW	570	* Check if the value of @state represents one of the supported states,
55ae4519 RW	571	* execute enter_state() and update system suspend statistics.
a9d70523 RW	572	*/
	573	int pm_suspend(suspend_state_t state)
	574	{
bc25cf50 RW	575	int error;
	576
	577	if (state <= PM_SUSPEND_ON \|\| state >= PM_SUSPEND_MAX)
	578	return -EINVAL;
	579
	580	error = enter_state(state);
	581	if (error) {
	582	suspend_stats.fail++;
	583	dpm_save_failed_errno(error);
	584	} else {
	585	suspend_stats.success++;
2a77c46d	586	}
bc25cf50	587	return error;
a9d70523 RW	588	}
a9d70523 RW	589	EXPORT_SYMBOL(pm_suspend);