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

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);
}

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

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

__setup("relative_sleep_states=", sleep_states_setup);

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

	lock_system_sleep();

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

	pm_states[PM_SUSPEND_FREEZE] = pm_labels[j];

	unlock_system_sleep();
}
EXPORT_SYMBOL_GPL(suspend_set_ops);

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

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

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

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

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

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

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

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

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

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

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

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

#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);
	printk(KERN_INFO "PM: Syncing filesystems ... ");
	sys_sync();
	printk("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
62109b43	35	const char *pm_labels[] = { "mem", "standby", "freeze", NULL };
d431cbc5	36	const char *pm_states[PM_SUSPEND_MAX];
a9d70523	37
ef25ba04 RW	38	unsigned int pm_suspend_global_flags;
	39	EXPORT_SYMBOL_GPL(pm_suspend_global_flags);
	40
2f55ac07	41	static const struct platform_suspend_ops *suspend_ops;
1f0b6386	42	static const struct platform_freeze_ops *freeze_ops;
7e73c5ae	43	static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head);
38106313 RW	44
	45	enum freeze_state __read_mostly suspend_freeze_state;
	46	static DEFINE_SPINLOCK(suspend_freeze_lock);
7e73c5ae	47
1f0b6386 RW	48	void freeze_set_ops(const struct platform_freeze_ops *ops)
	49	{
	50	lock_system_sleep();
	51	freeze_ops = ops;
	52	unlock_system_sleep();
	53	}
	54
7e73c5ae ZR	55	static void freeze_begin(void)
7e73c5ae ZR	56	{
38106313	57	suspend_freeze_state = FREEZE_STATE_NONE;
7e73c5ae ZR	58	}
	59
	60	static void freeze_enter(void)
	61	{
38106313 RW	62	spin_lock_irq(&suspend_freeze_lock);
	63	if (pm_wakeup_pending())
	64	goto out;
	65
	66	suspend_freeze_state = FREEZE_STATE_ENTER;
	67	spin_unlock_irq(&suspend_freeze_lock);
	68
	69	get_online_cpus();
f3f12532	70	cpuidle_resume();
38106313 RW	71
	72	/* Push all the CPUs into the idle loop. */
	73	wake_up_all_idle_cpus();
	74	pr_debug("PM: suspend-to-idle\n");
	75	/* Make the current CPU wait so it can enter the idle loop too. */
	76	wait_event(suspend_freeze_wait_head,
	77	suspend_freeze_state == FREEZE_STATE_WAKE);
	78	pr_debug("PM: resume from suspend-to-idle\n");
	79
f3f12532	80	cpuidle_pause();
38106313 RW	81	put_online_cpus();
	82
	83	spin_lock_irq(&suspend_freeze_lock);
	84
	85	out:
	86	suspend_freeze_state = FREEZE_STATE_NONE;
	87	spin_unlock_irq(&suspend_freeze_lock);
7e73c5ae ZR	88	}
	89
	90	void freeze_wake(void)
	91	{
38106313 RW	92	unsigned long flags;
	93
	94	spin_lock_irqsave(&suspend_freeze_lock, flags);
	95	if (suspend_freeze_state > FREEZE_STATE_NONE) {
	96	suspend_freeze_state = FREEZE_STATE_WAKE;
	97	wake_up(&suspend_freeze_wait_head);
	98	}
	99	spin_unlock_irqrestore(&suspend_freeze_lock, flags);
7e73c5ae ZR	100	}
	101	EXPORT_SYMBOL_GPL(freeze_wake);
	102
43e8317b RW	103	static bool valid_state(suspend_state_t state)
	104	{
	105	/*
	106	* PM_SUSPEND_STANDBY and PM_SUSPEND_MEM states need low level
	107	* support and need to be valid to the low level
	108	* implementation, no valid callback implies that none are valid.
	109	*/
	110	return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
	111	}
	112
0399d4db RW	113	/*
	114	* If this is set, the "mem" label always corresponds to the deepest sleep state
	115	* available, the "standby" label corresponds to the second deepest sleep state
	116	* available (if any), and the "freeze" label corresponds to the remaining
	117	* available sleep state (if there is one).
	118	*/
	119	static bool relative_states;
	120
	121	static int __init sleep_states_setup(char *str)
	122	{
	123	relative_states = !strncmp(str, "1", 1);
d431cbc5	124	pm_states[PM_SUSPEND_FREEZE] = pm_labels[relative_states ? 0 : 2];
0399d4db RW	125	return 1;
	126	}
	127
	128	__setup("relative_sleep_states=", sleep_states_setup);
	129
a9d70523	130	/**
55ae4519 RW	131	* suspend_set_ops - Set the global suspend method table.
55ae4519 RW	132	* @ops: Suspend operations to use.
a9d70523	133	*/
2f55ac07	134	void suspend_set_ops(const struct platform_suspend_ops *ops)
a9d70523	135	{
43e8317b	136	suspend_state_t i;
d431cbc5	137	int j = 0;
43e8317b	138
bcda53fa	139	lock_system_sleep();
43e8317b	140
a9d70523	141	suspend_ops = ops;
0399d4db	142	for (i = PM_SUSPEND_MEM; i >= PM_SUSPEND_STANDBY; i--)
d431cbc5 RW	143	if (valid_state(i)) {
	144	pm_states[i] = pm_labels[j++];
	145	} else if (!relative_states) {
	146	pm_states[i] = NULL;
	147	j++;
	148	}
0399d4db	149
d431cbc5	150	pm_states[PM_SUSPEND_FREEZE] = pm_labels[j];
43e8317b	151
bcda53fa	152	unlock_system_sleep();
a9d70523	153	}
a5e4fd87	154	EXPORT_SYMBOL_GPL(suspend_set_ops);
a9d70523	155
a9d70523	156	/**
55ae4519	157	* suspend_valid_only_mem - Generic memory-only valid callback.
a9d70523	158	*
55ae4519 RW	159	* Platform drivers that implement mem suspend only and only need to check for
	160	* that in their .valid() callback can use this instead of rolling their own
	161	* .valid() callback.
a9d70523 RW	162	*/
	163	int suspend_valid_only_mem(suspend_state_t state)
	164	{
	165	return state == PM_SUSPEND_MEM;
	166	}
a5e4fd87	167	EXPORT_SYMBOL_GPL(suspend_valid_only_mem);
a9d70523	168
8490fdf9 RW	169	static bool sleep_state_supported(suspend_state_t state)
	170	{
	171	return state == PM_SUSPEND_FREEZE \|\| (suspend_ops && suspend_ops->enter);
	172	}
	173
	174	static int platform_suspend_prepare(suspend_state_t state)
	175	{
	176	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare ?
	177	suspend_ops->prepare() : 0;
	178	}
	179
a8d46b9e RW	180	static int platform_suspend_prepare_late(suspend_state_t state)
a8d46b9e RW	181	{
403b9636	182	return state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->prepare ?
a8d46b9e RW	183	freeze_ops->prepare() : 0;
	184	}
	185
ebc3e41e	186	static int platform_suspend_prepare_noirq(suspend_state_t state)
8490fdf9 RW	187	{
	188	return state != PM_SUSPEND_FREEZE && suspend_ops->prepare_late ?
	189	suspend_ops->prepare_late() : 0;
	190	}
	191
ebc3e41e	192	static void platform_resume_noirq(suspend_state_t state)
8490fdf9 RW	193	{
	194	if (state != PM_SUSPEND_FREEZE && suspend_ops->wake)
	195	suspend_ops->wake();
	196	}
	197
a8d46b9e RW	198	static void platform_resume_early(suspend_state_t state)
a8d46b9e RW	199	{
403b9636	200	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->restore)
a8d46b9e RW	201	freeze_ops->restore();
	202	}
	203
ebc3e41e	204	static void platform_resume_finish(suspend_state_t state)
8490fdf9 RW	205	{
	206	if (state != PM_SUSPEND_FREEZE && suspend_ops->finish)
	207	suspend_ops->finish();
	208	}
	209
	210	static int platform_suspend_begin(suspend_state_t state)
	211	{
	212	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->begin)
	213	return freeze_ops->begin();
	214	else if (suspend_ops->begin)
	215	return suspend_ops->begin(state);
	216	else
	217	return 0;
	218	}
	219
ebc3e41e	220	static void platform_resume_end(suspend_state_t state)
8490fdf9 RW	221	{
	222	if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
	223	freeze_ops->end();
	224	else if (suspend_ops->end)
	225	suspend_ops->end();
	226	}
	227
ebc3e41e	228	static void platform_recover(suspend_state_t state)
8490fdf9 RW	229	{
	230	if (state != PM_SUSPEND_FREEZE && suspend_ops->recover)
	231	suspend_ops->recover();
	232	}
	233
	234	static bool platform_suspend_again(suspend_state_t state)
	235	{
	236	return state != PM_SUSPEND_FREEZE && suspend_ops->suspend_again ?
	237	suspend_ops->suspend_again() : false;
	238	}
	239
1d4a9c17 BN	240	#ifdef CONFIG_PM_DEBUG
	241	static unsigned int pm_test_delay = 5;
	242	module_param(pm_test_delay, uint, 0644);
	243	MODULE_PARM_DESC(pm_test_delay,
	244	"Number of seconds to wait before resuming from suspend test");
	245	#endif
	246
a9d70523 RW	247	static int suspend_test(int level)
	248	{
	249	#ifdef CONFIG_PM_DEBUG
	250	if (pm_test_level == level) {
22e09b33	251	pr_info("suspend debug: Waiting for %d second(s).\n",
1d4a9c17 BN	252	pm_test_delay);
1d4a9c17 BN	253	mdelay(pm_test_delay * 1000);
a9d70523 RW	254	return 1;
	255	}
	256	#endif /* !CONFIG_PM_DEBUG */
	257	return 0;
	258	}
	259
	260	/**
55ae4519	261	* suspend_prepare - Prepare for entering system sleep state.
a9d70523	262	*
55ae4519 RW	263	* Common code run for every system sleep state that can be entered (except for
	264	* hibernation). Run suspend notifiers, allocate the "suspend" console and
	265	* freeze processes.
a9d70523	266	*/
7e73c5ae	267	static int suspend_prepare(suspend_state_t state)
a9d70523	268	{
ea00f4f4	269	int error, nr_calls = 0;
a9d70523	270
8490fdf9	271	if (!sleep_state_supported(state))
a9d70523 RW	272	return -EPERM;
	273
	274	pm_prepare_console();
	275
ea00f4f4 LW	276	error = __pm_notifier_call_chain(PM_SUSPEND_PREPARE, -1, &nr_calls);
	277	if (error) {
	278	nr_calls--;
a9d70523	279	goto Finish;
ea00f4f4	280	}
a9d70523	281
bb3632c6	282	trace_suspend_resume(TPS("freeze_processes"), 0, true);
a9d70523	283	error = suspend_freeze_processes();
bb3632c6	284	trace_suspend_resume(TPS("freeze_processes"), 0, false);
03afed8b	285	if (!error)
a9d70523 RW	286	return 0;
a9d70523 RW	287
03afed8b TH	288	suspend_stats.failed_freeze++;
03afed8b TH	289	dpm_save_failed_step(SUSPEND_FREEZE);
a9d70523	290	Finish:
ea00f4f4	291	__pm_notifier_call_chain(PM_POST_SUSPEND, nr_calls, NULL);
a9d70523 RW	292	pm_restore_console();
	293	return error;
	294	}
	295
	296	/* default implementation */
52f5684c	297	void __weak arch_suspend_disable_irqs(void)
a9d70523 RW	298	{
	299	local_irq_disable();
	300	}
	301
	302	/* default implementation */
52f5684c	303	void __weak arch_suspend_enable_irqs(void)
a9d70523 RW	304	{
	305	local_irq_enable();
	306	}
	307
	308	/**
55ae4519 RW	309	* suspend_enter - Make the system enter the given sleep state.
	310	* @state: System sleep state to enter.
	311	* @wakeup: Returns information that the sleep state should not be re-entered.
a9d70523	312	*
3b5fe852	313	* This function should be called after devices have been suspended.
a9d70523	314	*/
3b5fe852	315	static int suspend_enter(suspend_state_t state, bool *wakeup)
a9d70523 RW	316	{
	317	int error;
	318
8490fdf9 RW	319	error = platform_suspend_prepare(state);
	320	if (error)
	321	goto Platform_finish;
a9d70523	322
2a8a8ce6	323	error = dpm_suspend_late(PMSG_SUSPEND);
a9d70523	324	if (error) {
22e09b33	325	pr_err("PM: late suspend of devices failed\n");
ce441011	326	goto Platform_finish;
a9d70523	327	}
a8d46b9e RW	328	error = platform_suspend_prepare_late(state);
	329	if (error)
	330	goto Devices_early_resume;
	331
2a8a8ce6 RW	332	error = dpm_suspend_noirq(PMSG_SUSPEND);
2a8a8ce6 RW	333	if (error) {
22e09b33	334	pr_err("PM: noirq suspend of devices failed\n");
a8d46b9e	335	goto Platform_early_resume;
2a8a8ce6	336	}
ebc3e41e	337	error = platform_suspend_prepare_noirq(state);
8490fdf9 RW	338	if (error)
8490fdf9 RW	339	goto Platform_wake;
a9d70523	340
08605acc ZR	341	if (suspend_test(TEST_PLATFORM))
	342	goto Platform_wake;
	343
7e73c5ae ZR	344	/*
	345	* PM_SUSPEND_FREEZE equals
	346	* frozen processes + suspended devices + idle processors.
	347	* Thus we should invoke freeze_enter() soon after
	348	* all the devices are suspended.
	349	*/
	350	if (state == PM_SUSPEND_FREEZE) {
bb3632c6	351	trace_suspend_resume(TPS("machine_suspend"), state, true);
7e73c5ae	352	freeze_enter();
bb3632c6	353	trace_suspend_resume(TPS("machine_suspend"), state, false);
7e73c5ae ZR	354	goto Platform_wake;
	355	}
	356
a9d70523 RW	357	error = disable_nonboot_cpus();
	358	if (error \|\| suspend_test(TEST_CPUS))
	359	goto Enable_cpus;
	360
	361	arch_suspend_disable_irqs();
	362	BUG_ON(!irqs_disabled());
	363
2e711c04	364	error = syscore_suspend();
a9d70523	365	if (!error) {
3b5fe852 MH	366	*wakeup = pm_wakeup_pending();
3b5fe852 MH	367	if (!(suspend_test(TEST_CORE) \|\| *wakeup)) {
bb3632c6 TB	368	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	369	state, true);
a9d70523	370	error = suspend_ops->enter(state);
bb3632c6 TB	371	trace_suspend_resume(TPS("machine_suspend"),
bb3632c6 TB	372	state, false);
c125e96f	373	events_check_enabled = false;
67176736 RK	374	} else if (*wakeup) {
67176736 RK	375	error = -EBUSY;
c125e96f	376	}
40dc166c	377	syscore_resume();
a9d70523 RW	378	}
	379
	380	arch_suspend_enable_irqs();
	381	BUG_ON(irqs_disabled());
	382
	383	Enable_cpus:
	384	enable_nonboot_cpus();
	385
	386	Platform_wake:
ebc3e41e	387	platform_resume_noirq(state);
2a8a8ce6 RW	388	dpm_resume_noirq(PMSG_RESUME);
2a8a8ce6 RW	389
a8d46b9e RW	390	Platform_early_resume:
	391	platform_resume_early(state);
	392
2a8a8ce6 RW	393	Devices_early_resume:
2a8a8ce6 RW	394	dpm_resume_early(PMSG_RESUME);
a9d70523	395
ce441011	396	Platform_finish:
ebc3e41e	397	platform_resume_finish(state);
a9d70523 RW	398	return error;
	399	}
	400
	401	/**
55ae4519 RW	402	* suspend_devices_and_enter - Suspend devices and enter system sleep state.
55ae4519 RW	403	* @state: System sleep state to enter.
a9d70523 RW	404	*/
	405	int suspend_devices_and_enter(suspend_state_t state)
	406	{
	407	int error;
3b5fe852	408	bool wakeup = false;
a9d70523	409
8490fdf9	410	if (!sleep_state_supported(state))
a9d70523 RW	411	return -ENOSYS;
a9d70523 RW	412
8490fdf9 RW	413	error = platform_suspend_begin(state);
	414	if (error)
	415	goto Close;
	416
a9d70523 RW	417	suspend_console();
	418	suspend_test_start();
	419	error = dpm_suspend_start(PMSG_SUSPEND);
	420	if (error) {
9350de06	421	pr_err("PM: Some devices failed to suspend, or early wake event detected\n");
a9d70523 RW	422	goto Recover_platform;
	423	}
	424	suspend_test_finish("suspend devices");
	425	if (suspend_test(TEST_DEVICES))
	426	goto Recover_platform;
	427
3b5fe852 MH	428	do {
3b5fe852 MH	429	error = suspend_enter(state, &wakeup);
8490fdf9	430	} while (!error && !wakeup && platform_suspend_again(state));
a9d70523 RW	431
	432	Resume_devices:
	433	suspend_test_start();
	434	dpm_resume_end(PMSG_RESUME);
	435	suspend_test_finish("resume devices");
0cadc702	436	trace_suspend_resume(TPS("resume_console"), state, true);
a9d70523	437	resume_console();
0cadc702	438	trace_suspend_resume(TPS("resume_console"), state, false);
1f0b6386	439
8490fdf9	440	Close:
ebc3e41e	441	platform_resume_end(state);
a9d70523 RW	442	return error;
	443
	444	Recover_platform:
ebc3e41e	445	platform_recover(state);
a9d70523 RW	446	goto Resume_devices;
	447	}
	448
	449	/**
55ae4519	450	* suspend_finish - Clean up before finishing the suspend sequence.
a9d70523	451	*
55ae4519 RW	452	* Call platform code to clean up, restart processes, and free the console that
55ae4519 RW	453	* we've allocated. This routine is not called for hibernation.
a9d70523 RW	454	*/
	455	static void suspend_finish(void)
	456	{
	457	suspend_thaw_processes();
a9d70523 RW	458	pm_notifier_call_chain(PM_POST_SUSPEND);
	459	pm_restore_console();
	460	}
	461
	462	/**
55ae4519 RW	463	* enter_state - Do common work needed to enter system sleep state.
55ae4519 RW	464	* @state: System sleep state to enter.
a9d70523	465	*
55ae4519 RW	466	* Make sure that no one else is trying to put the system into a sleep state.
	467	* Fail if that's not the case. Otherwise, prepare for system suspend, make the
	468	* system enter the given sleep state and clean up after wakeup.
a9d70523	469	*/
93e1ee43	470	static int enter_state(suspend_state_t state)
a9d70523 RW	471	{
	472	int error;
	473
bb3632c6	474	trace_suspend_resume(TPS("suspend_enter"), state, true);
43e8317b RW	475	if (state == PM_SUSPEND_FREEZE) {
	476	#ifdef CONFIG_PM_DEBUG
	477	if (pm_test_level != TEST_NONE && pm_test_level <= TEST_CPUS) {
a395d6a7	478	pr_warn("PM: Unsupported test mode for suspend to idle, please choose none/freezer/devices/platform.\n");
43e8317b RW	479	return -EAGAIN;
	480	}
	481	#endif
	482	} else if (!valid_state(state)) {
	483	return -EINVAL;
	484	}
a9d70523 RW	485	if (!mutex_trylock(&pm_mutex))
	486	return -EBUSY;
	487
7e73c5ae ZR	488	if (state == PM_SUSPEND_FREEZE)
	489	freeze_begin();
	490
2fd77fff	491	#ifndef CONFIG_SUSPEND_SKIP_SYNC
bb3632c6	492	trace_suspend_resume(TPS("sync_filesystems"), 0, true);
a9d70523 RW	493	printk(KERN_INFO "PM: Syncing filesystems ... ");
	494	sys_sync();
	495	printk("done.\n");
bb3632c6	496	trace_suspend_resume(TPS("sync_filesystems"), 0, false);
2fd77fff	497	#endif
a9d70523	498
a9215045	499	pr_debug("PM: Preparing system for sleep (%s)\n", pm_states[state]);
ef25ba04	500	pm_suspend_clear_flags();
7e73c5ae	501	error = suspend_prepare(state);
a9d70523 RW	502	if (error)
	503	goto Unlock;
	504
	505	if (suspend_test(TEST_FREEZER))
	506	goto Finish;
	507
bb3632c6	508	trace_suspend_resume(TPS("suspend_enter"), state, false);
a9215045	509	pr_debug("PM: Suspending system (%s)\n", pm_states[state]);
87186475	510	pm_restrict_gfp_mask();
a9d70523	511	error = suspend_devices_and_enter(state);
87186475	512	pm_restore_gfp_mask();
a9d70523 RW	513
	514	Finish:
	515	pr_debug("PM: Finishing wakeup.\n");
	516	suspend_finish();
	517	Unlock:
	518	mutex_unlock(&pm_mutex);
	519	return error;
	520	}
	521
	522	/**
55ae4519 RW	523	* pm_suspend - Externally visible function for suspending the system.
55ae4519 RW	524	* @state: System sleep state to enter.
a9d70523	525	*
55ae4519 RW	526	* Check if the value of @state represents one of the supported states,
55ae4519 RW	527	* execute enter_state() and update system suspend statistics.
a9d70523 RW	528	*/
	529	int pm_suspend(suspend_state_t state)
	530	{
bc25cf50 RW	531	int error;
	532
	533	if (state <= PM_SUSPEND_ON \|\| state >= PM_SUSPEND_MAX)
	534	return -EINVAL;
	535
	536	error = enter_state(state);
	537	if (error) {
	538	suspend_stats.fail++;
	539	dpm_save_failed_errno(error);
	540	} else {
	541	suspend_stats.success++;
2a77c46d	542	}
bc25cf50	543	return error;
a9d70523 RW	544	}
a9d70523 RW	545	EXPORT_SYMBOL(pm_suspend);