[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)
{
	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);
}

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) {
		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;
		} 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	{
38106313 RW	75	spin_lock_irq(&suspend_freeze_lock);
	76	if (pm_wakeup_pending())
	77	goto out;
	78
	79	suspend_freeze_state = FREEZE_STATE_ENTER;
	80	spin_unlock_irq(&suspend_freeze_lock);
	81
	82	get_online_cpus();
f3f12532	83	cpuidle_resume();
38106313 RW	84
	85	/* Push all the CPUs into the idle loop. */
	86	wake_up_all_idle_cpus();
	87	pr_debug("PM: suspend-to-idle\n");
	88	/* Make the current CPU wait so it can enter the idle loop too. */
	89	wait_event(suspend_freeze_wait_head,
	90	suspend_freeze_state == FREEZE_STATE_WAKE);
	91	pr_debug("PM: resume from suspend-to-idle\n");
	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);
7e73c5ae ZR	101	}
	102
	103	void freeze_wake(void)
	104	{
38106313 RW	105	unsigned long flags;
	106
	107	spin_lock_irqsave(&suspend_freeze_lock, flags);
	108	if (suspend_freeze_state > FREEZE_STATE_NONE) {
	109	suspend_freeze_state = FREEZE_STATE_WAKE;
	110	wake_up(&suspend_freeze_wait_head);
	111	}
	112	spin_unlock_irqrestore(&suspend_freeze_lock, flags);
7e73c5ae ZR	113	}
	114	EXPORT_SYMBOL_GPL(freeze_wake);
	115
43e8317b RW	116	static bool valid_state(suspend_state_t state)
	117	{
	118	/*
	119	* PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
	120	* support and need to be valid to the low level
	121	* implementation, no valid callback implies that none are valid.
	122	*/
	123	return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
	124	}
	125
fa7fd6fa SH	126	void __init pm_states_init(void)
fa7fd6fa SH	127	{
406e7938 RW	128	/* "mem" and "freeze" are always present in /sys/power/state. */
	129	pm_states[PM_SUSPEND_MEM] = pm_labels[PM_SUSPEND_MEM];
	130	pm_states[PM_SUSPEND_FREEZE] = pm_labels[PM_SUSPEND_FREEZE];
fa7fd6fa	131	/*
406e7938 RW	132	* Suspend-to-idle should be supported even without any suspend_ops,
406e7938 RW	133	* initialize mem_sleep_states[] accordingly here.
fa7fd6fa	134	*/
406e7938	135	mem_sleep_states[PM_SUSPEND_FREEZE] = mem_sleep_labels[PM_SUSPEND_FREEZE];
fa7fd6fa SH	136	}
fa7fd6fa SH	137
406e7938	138	static int __init mem_sleep_default_setup(char *str)
0399d4db	139	{
406e7938 RW	140	suspend_state_t state;
	141
	142	for (state = PM_SUSPEND_FREEZE; state <= PM_SUSPEND_MEM; state++)
	143	if (mem_sleep_labels[state] &&
	144	!strcmp(str, mem_sleep_labels[state])) {
	145	mem_sleep_default = state;
	146	break;
	147	}
	148
0399d4db RW	149	return 1;
0399d4db RW	150	}
406e7938	151	__setup("mem_sleep_default=", mem_sleep_default_setup);
0399d4db	152
a9d70523	153	/**
55ae4519 RW	154	* suspend_set_ops - Set the global suspend method table.
55ae4519 RW	155	* @ops: Suspend operations to use.
a9d70523	156	*/
2f55ac07	157	void suspend_set_ops(const struct platform_suspend_ops *ops)
a9d70523	158	{
bcda53fa	159	lock_system_sleep();
43e8317b	160
a9d70523	161	suspend_ops = ops;
0399d4db	162
406e7938 RW	163	if (valid_state(PM_SUSPEND_STANDBY)) {
	164	mem_sleep_states[PM_SUSPEND_STANDBY] = mem_sleep_labels[PM_SUSPEND_STANDBY];
	165	pm_states[PM_SUSPEND_STANDBY] = pm_labels[PM_SUSPEND_STANDBY];
	166	if (mem_sleep_default == PM_SUSPEND_STANDBY)
	167	mem_sleep_current = PM_SUSPEND_STANDBY;
	168	}
	169	if (valid_state(PM_SUSPEND_MEM)) {
	170	mem_sleep_states[PM_SUSPEND_MEM] = mem_sleep_labels[PM_SUSPEND_MEM];
e326ce01	171	if (mem_sleep_default == PM_SUSPEND_MEM)
406e7938 RW	172	mem_sleep_current = PM_SUSPEND_MEM;
406e7938 RW	173	}
43e8317b	174
bcda53fa	175	unlock_system_sleep();
a9d70523	176	}
a5e4fd87	177	EXPORT_SYMBOL_GPL(suspend_set_ops);
a9d70523	178
a9d70523	179	/**
55ae4519	180	* suspend_valid_only_mem - Generic memory-only valid callback.
a9d70523	181	*
55ae4519 RW	182	* Platform drivers that implement mem suspend only and only need to check for
	183	* that in their .valid() callback can use this instead of rolling their own
	184	* .valid() callback.
a9d70523 RW	185	*/
	186	int suspend_valid_only_mem(suspend_state_t state)
	187	{
	188	return state == PM_SUSPEND_MEM;
	189	}
a5e4fd87	190	EXPORT_SYMBOL_GPL(suspend_valid_only_mem);
a9d70523	191
8490fdf9 RW	192	static bool sleep_state_supported(suspend_state_t state)
	193	{
	194	return state == PM_SUSPEND_FREEZE \|\| (suspend_ops && suspend_ops->enter);
	195	}
	196
	197	static int platform_suspend_prepare(suspend_state_t state)
	198	{
	199	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare ?
	200	suspend_ops->prepare() : 0;
	201	}
	202
a8d46b9e RW	203	static int platform_suspend_prepare_late(suspend_state_t state)
a8d46b9e RW	204	{
403b9636	205	return state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->prepare ?
a8d46b9e RW	206	freeze_ops->prepare() : 0;
	207	}
	208
ebc3e41e	209	static int platform_suspend_prepare_noirq(suspend_state_t state)
8490fdf9 RW	210	{
	211	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare_late ?
	212	suspend_ops->prepare_late() : 0;
	213	}
	214
ebc3e41e	215	static void platform_resume_noirq(suspend_state_t state)
8490fdf9 RW	216	{
	217	if (state != PM_SUSPEND_FREEZE && suspend_ops->wake)
	218	suspend_ops->wake();
	219	}
	220
a8d46b9e RW	221	static void platform_resume_early(suspend_state_t state)
a8d46b9e RW	222	{
403b9636	223	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->restore)
a8d46b9e RW	224	freeze_ops->restore();
	225	}
	226
ebc3e41e	227	static void platform_resume_finish(suspend_state_t state)
8490fdf9 RW	228	{
	229	if (state != PM_SUSPEND_FREEZE && suspend_ops->finish)
	230	suspend_ops->finish();
	231	}
	232
	233	static int platform_suspend_begin(suspend_state_t state)
	234	{
	235	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->begin)
	236	return freeze_ops->begin();
fa7fd6fa	237	else if (suspend_ops && suspend_ops->begin)
8490fdf9 RW	238	return suspend_ops->begin(state);
	239	else
	240	return 0;
	241	}
	242
ebc3e41e	243	static void platform_resume_end(suspend_state_t state)
8490fdf9 RW	244	{
	245	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
	246	freeze_ops->end();
fa7fd6fa	247	else if (suspend_ops && suspend_ops->end)
8490fdf9 RW	248	suspend_ops->end();
	249	}
	250
ebc3e41e	251	static void platform_recover(suspend_state_t state)
8490fdf9 RW	252	{
	253	if (state != PM_SUSPEND_FREEZE && suspend_ops->recover)
	254	suspend_ops->recover();
	255	}
	256
	257	static bool platform_suspend_again(suspend_state_t state)
	258	{
	259	return state != PM_SUSPEND_FREEZE && suspend_ops->suspend_again ?
	260	suspend_ops->suspend_again() : false;
	261	}
	262
1d4a9c17 BN	263	#ifdef CONFIG_PM_DEBUG
	264	static unsigned int pm_test_delay = 5;
	265	module_param(pm_test_delay, uint, 0644);
	266	MODULE_PARM_DESC(pm_test_delay,
	267	"Number of seconds to wait before resuming from suspend test");
	268	#endif
	269
a9d70523 RW	270	static int suspend_test(int level)
	271	{
	272	#ifdef CONFIG_PM_DEBUG
	273	if (pm_test_level == level) {
22e09b33	274	pr_info("suspend debug: Waiting for %d second(s).\n",
1d4a9c17 BN	275	pm_test_delay);
1d4a9c17 BN	276	mdelay(pm_test_delay * 1000);
a9d70523 RW	277	return 1;
	278	}
	279	#endif /* !CONFIG_PM_DEBUG */
	280	return 0;
	281	}
	282
	283	/**
55ae4519	284	* suspend_prepare - Prepare for entering system sleep state.
a9d70523	285	*
55ae4519 RW	286	* Common code run for every system sleep state that can be entered (except for
	287	* hibernation). Run suspend notifiers, allocate the "suspend" console and
	288	* freeze processes.
a9d70523	289	*/
7e73c5ae	290	static int suspend_prepare(suspend_state_t state)
a9d70523	291	{
ea00f4f4	292	int error, nr_calls = 0;
a9d70523	293
8490fdf9	294	if (!sleep_state_supported(state))
a9d70523 RW	295	return -EPERM;
	296
	297	pm_prepare_console();
	298
ea00f4f4 LW	299	error = __pm_notifier_call_chain(PM_SUSPEND_PREPARE, -1, &nr_calls);
	300	if (error) {
	301	nr_calls--;
a9d70523	302	goto Finish;
ea00f4f4	303	}
a9d70523	304
bb3632c6	305	trace_suspend_resume(TPS("freeze_processes"), 0, true);
a9d70523	306	error = suspend_freeze_processes();
bb3632c6	307	trace_suspend_resume(TPS("freeze_processes"), 0, false);
03afed8b	308	if (!error)
a9d70523 RW	309	return 0;
a9d70523 RW	310
03afed8b TH	311	suspend_stats.failed_freeze++;
03afed8b TH	312	dpm_save_failed_step(SUSPEND_FREEZE);
a9d70523	313	Finish:
ea00f4f4	314	__pm_notifier_call_chain(PM_POST_SUSPEND, nr_calls, NULL);
a9d70523 RW	315	pm_restore_console();
	316	return error;
	317	}
	318
	319	/* default implementation */
52f5684c	320	void __weak arch_suspend_disable_irqs(void)
a9d70523 RW	321	{
	322	local_irq_disable();
	323	}
	324
	325	/* default implementation */
52f5684c	326	void __weak arch_suspend_enable_irqs(void)
a9d70523 RW	327	{
	328	local_irq_enable();
	329	}
	330
	331	/**
55ae4519 RW	332	* suspend_enter - Make the system enter the given sleep state.
	333	* @state: System sleep state to enter.
	334	* @wakeup: Returns information that the sleep state should not be re-entered.
a9d70523	335	*
3b5fe852	336	* This function should be called after devices have been suspended.
a9d70523	337	*/
3b5fe852	338	static int suspend_enter(suspend_state_t state, bool *wakeup)
a9d70523 RW	339	{
	340	int error;
	341
8490fdf9 RW	342	error = platform_suspend_prepare(state);
	343	if (error)
	344	goto Platform_finish;
a9d70523	345
2a8a8ce6	346	error = dpm_suspend_late(PMSG_SUSPEND);
a9d70523	347	if (error) {
22e09b33	348	pr_err("PM: late suspend of devices failed\n");
ce441011	349	goto Platform_finish;
a9d70523	350	}
a8d46b9e RW	351	error = platform_suspend_prepare_late(state);
	352	if (error)
	353	goto Devices_early_resume;
	354
2a8a8ce6 RW	355	error = dpm_suspend_noirq(PMSG_SUSPEND);
2a8a8ce6 RW	356	if (error) {
22e09b33	357	pr_err("PM: noirq suspend of devices failed\n");
a8d46b9e	358	goto Platform_early_resume;
2a8a8ce6	359	}
ebc3e41e	360	error = platform_suspend_prepare_noirq(state);
8490fdf9 RW	361	if (error)
8490fdf9 RW	362	goto Platform_wake;
a9d70523	363
08605acc ZR	364	if (suspend_test(TEST_PLATFORM))
	365	goto Platform_wake;
	366
7e73c5ae ZR	367	/*
	368	* PM_SUSPEND_FREEZE equals
	369	* frozen processes + suspended devices + idle processors.
	370	* Thus we should invoke freeze_enter() soon after
	371	* all the devices are suspended.
	372	*/
	373	if (state == PM_SUSPEND_FREEZE) {
f3b7eaae RW	374	trace_suspend_resume(TPS("machine_suspend"), state, true);
	375	freeze_enter();
	376	trace_suspend_resume(TPS("machine_suspend"), state, false);
	377	goto Platform_wake;
7e73c5ae ZR	378	}
7e73c5ae ZR	379
a9d70523 RW	380	error = disable_nonboot_cpus();
	381	if (error \|\| suspend_test(TEST_CPUS))
	382	goto Enable_cpus;
	383
	384	arch_suspend_disable_irqs();
	385	BUG_ON(!irqs_disabled());
	386
2e711c04	387	error = syscore_suspend();
a9d70523	388	if (!error) {
3b5fe852 MH	389	*wakeup = pm_wakeup_pending();
3b5fe852 MH	390	if (!(suspend_test(TEST_CORE) \|\| *wakeup)) {
bb3632c6 TB	391	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	392	state, true);
a9d70523	393	error = suspend_ops->enter(state);
bb3632c6 TB	394	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	395	state, false);
c125e96f	396	events_check_enabled = false;
67176736 RK	397	} else if (*wakeup) {
67176736 RK	398	error = -EBUSY;
c125e96f	399	}
40dc166c	400	syscore_resume();
a9d70523 RW	401	}
	402
	403	arch_suspend_enable_irqs();
	404	BUG_ON(irqs_disabled());
	405
	406	Enable_cpus:
	407	enable_nonboot_cpus();
	408
	409	Platform_wake:
ebc3e41e	410	platform_resume_noirq(state);
2a8a8ce6 RW	411	dpm_resume_noirq(PMSG_RESUME);
2a8a8ce6 RW	412
a8d46b9e RW	413	Platform_early_resume:
	414	platform_resume_early(state);
	415
2a8a8ce6 RW	416	Devices_early_resume:
2a8a8ce6 RW	417	dpm_resume_early(PMSG_RESUME);
a9d70523	418
ce441011	419	Platform_finish:
ebc3e41e	420	platform_resume_finish(state);
a9d70523 RW	421	return error;
	422	}
	423
	424	/**
55ae4519 RW	425	* suspend_devices_and_enter - Suspend devices and enter system sleep state.
55ae4519 RW	426	* @state: System sleep state to enter.
a9d70523 RW	427	*/
	428	int suspend_devices_and_enter(suspend_state_t state)
	429	{
	430	int error;
3b5fe852	431	bool wakeup = false;
a9d70523	432
8490fdf9	433	if (!sleep_state_supported(state))
a9d70523 RW	434	return -ENOSYS;
a9d70523 RW	435
8490fdf9 RW	436	error = platform_suspend_begin(state);
	437	if (error)
	438	goto Close;
	439
a9d70523 RW	440	suspend_console();
	441	suspend_test_start();
	442	error = dpm_suspend_start(PMSG_SUSPEND);
	443	if (error) {
9350de06	444	pr_err("PM: Some devices failed to suspend, or early wake event detected\n");
a9d70523 RW	445	goto Recover_platform;
	446	}
	447	suspend_test_finish("suspend devices");
	448	if (suspend_test(TEST_DEVICES))
	449	goto Recover_platform;
	450
3b5fe852 MH	451	do {
3b5fe852 MH	452	error = suspend_enter(state, &wakeup);
8490fdf9	453	} while (!error && !wakeup && platform_suspend_again(state));
a9d70523 RW	454
	455	Resume_devices:
	456	suspend_test_start();
	457	dpm_resume_end(PMSG_RESUME);
	458	suspend_test_finish("resume devices");
0cadc702	459	trace_suspend_resume(TPS("resume_console"), state, true);
a9d70523	460	resume_console();
0cadc702	461	trace_suspend_resume(TPS("resume_console"), state, false);
1f0b6386	462
8490fdf9	463	Close:
ebc3e41e	464	platform_resume_end(state);
a9d70523 RW	465	return error;
	466
	467	Recover_platform:
ebc3e41e	468	platform_recover(state);
a9d70523 RW	469	goto Resume_devices;
	470	}
	471
	472	/**
55ae4519	473	* suspend_finish - Clean up before finishing the suspend sequence.
a9d70523	474	*
55ae4519 RW	475	* Call platform code to clean up, restart processes, and free the console that
55ae4519 RW	476	* we've allocated. This routine is not called for hibernation.
a9d70523 RW	477	*/
	478	static void suspend_finish(void)
	479	{
	480	suspend_thaw_processes();
a9d70523 RW	481	pm_notifier_call_chain(PM_POST_SUSPEND);
	482	pm_restore_console();
	483	}
	484
	485	/**
55ae4519 RW	486	* enter_state - Do common work needed to enter system sleep state.
55ae4519 RW	487	* @state: System sleep state to enter.
a9d70523	488	*
55ae4519 RW	489	* Make sure that no one else is trying to put the system into a sleep state.
	490	* Fail if that's not the case. Otherwise, prepare for system suspend, make the
	491	* system enter the given sleep state and clean up after wakeup.
a9d70523	492	*/
93e1ee43	493	static int enter_state(suspend_state_t state)
a9d70523 RW	494	{
	495	int error;
	496
bb3632c6	497	trace_suspend_resume(TPS("suspend_enter"), state, true);
43e8317b RW	498	if (state == PM_SUSPEND_FREEZE) {
	499	#ifdef CONFIG_PM_DEBUG
	500	if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
a395d6a7	501	pr_warn("PM: Unsupported test mode for suspend to idle, please choose none/freezer/devices/platform.\n");
43e8317b RW	502	return -EAGAIN;
	503	}
	504	#endif
	505	} else if (!valid_state(state)) {
	506	return -EINVAL;
	507	}
a9d70523 RW	508	if (!mutex_trylock(&pm_mutex))
	509	return -EBUSY;
	510
7e73c5ae ZR	511	if (state == PM_SUSPEND_FREEZE)
	512	freeze_begin();
	513
2fd77fff	514	#ifndef CONFIG_SUSPEND_SKIP_SYNC
bb3632c6	515	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
1adb469b	516	pr_info("PM: Syncing filesystems ... ");
a9d70523	517	sys_sync();
1adb469b	518	pr_cont("done.\n");
bb3632c6	519	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
2fd77fff	520	#endif
a9d70523	521
a9215045	522	pr_debug("PM: Preparing system for sleep (%s)\n", pm_states[state]);
ef25ba04	523	pm_suspend_clear_flags();
7e73c5ae	524	error = suspend_prepare(state);
a9d70523 RW	525	if (error)
	526	goto Unlock;
	527
	528	if (suspend_test(TEST_FREEZER))
	529	goto Finish;
	530
bb3632c6	531	trace_suspend_resume(TPS("suspend_enter"), state, false);
a9215045	532	pr_debug("PM: Suspending system (%s)\n", pm_states[state]);
87186475	533	pm_restrict_gfp_mask();
a9d70523	534	error = suspend_devices_and_enter(state);
87186475	535	pm_restore_gfp_mask();
a9d70523 RW	536
	537	Finish:
	538	pr_debug("PM: Finishing wakeup.\n");
	539	suspend_finish();
	540	Unlock:
	541	mutex_unlock(&pm_mutex);
	542	return error;
	543	}
	544
	545	/**
55ae4519 RW	546	* pm_suspend - Externally visible function for suspending the system.
55ae4519 RW	547	* @state: System sleep state to enter.
a9d70523	548	*
55ae4519 RW	549	* Check if the value of @state represents one of the supported states,
55ae4519 RW	550	* execute enter_state() and update system suspend statistics.
a9d70523 RW	551	*/
	552	int pm_suspend(suspend_state_t state)
	553	{
bc25cf50 RW	554	int error;
	555
	556	if (state <= PM_SUSPEND_ON \|\| state >= PM_SUSPEND_MAX)
	557	return -EINVAL;
	558
	559	error = enter_state(state);
	560	if (error) {
	561	suspend_stats.fail++;
	562	dpm_save_failed_errno(error);
	563	} else {
	564	suspend_stats.success++;
2a77c46d	565	}
bc25cf50	566	return error;
a9d70523 RW	567	}
a9d70523 RW	568	EXPORT_SYMBOL(pm_suspend);