[deliverable/linux.git] / kernel / power / main.c

/*
 * kernel/power/main.c - PM subsystem core functionality.
 *
 * Copyright (c) 2003 Patrick Mochel
 * Copyright (c) 2003 Open Source Development Lab
 *
 * This file is released under the GPLv2
 *
 */

#include <linux/export.h>
#include <linux/kobject.h>
#include <linux/string.h>
#include <linux/pm-trace.h>
#include <linux/workqueue.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>

#include "power.h"

DEFINE_MUTEX(pm_mutex);

#ifdef CONFIG_PM_SLEEP

/* Routines for PM-transition notifications */

static BLOCKING_NOTIFIER_HEAD(pm_chain_head);

int register_pm_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_register(&pm_chain_head, nb);
}
EXPORT_SYMBOL_GPL(register_pm_notifier);

int unregister_pm_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_unregister(&pm_chain_head, nb);
}
EXPORT_SYMBOL_GPL(unregister_pm_notifier);

int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
{
	int ret;

	ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
						nr_to_call, nr_calls);

	return notifier_to_errno(ret);
}
int pm_notifier_call_chain(unsigned long val)
{
	return __pm_notifier_call_chain(val, -1, NULL);
}

/* If set, devices may be suspended and resumed asynchronously. */
int pm_async_enabled = 1;

static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
			     char *buf)
{
	return sprintf(buf, "%d\n", pm_async_enabled);
}

static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
			      const char *buf, size_t n)
{
	unsigned long val;

	if (kstrtoul(buf, 10, &val))
		return -EINVAL;

	if (val > 1)
		return -EINVAL;

	pm_async_enabled = val;
	return n;
}

power_attr(pm_async);

#ifdef CONFIG_PM_DEBUG
int pm_test_level = TEST_NONE;

static const char * const pm_tests[__TEST_AFTER_LAST] = {
	[TEST_NONE] = "none",
	[TEST_CORE] = "core",
	[TEST_CPUS] = "processors",
	[TEST_PLATFORM] = "platform",
	[TEST_DEVICES] = "devices",
	[TEST_FREEZER] = "freezer",
};

static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
				char *buf)
{
	char *s = buf;
	int level;

	for (level = TEST_FIRST; level <= TEST_MAX; level++)
		if (pm_tests[level]) {
			if (level == pm_test_level)
				s += sprintf(s, "[%s] ", pm_tests[level]);
			else
				s += sprintf(s, "%s ", pm_tests[level]);
		}

	if (s != buf)
		/* convert the last space to a newline */
		*(s-1) = '\n';

	return (s - buf);
}

static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
				const char *buf, size_t n)
{
	const char * const *s;
	int level;
	char *p;
	int len;
	int error = -EINVAL;

	p = memchr(buf, '\n', n);
	len = p ? p - buf : n;

	lock_system_sleep();

	level = TEST_FIRST;
	for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
		if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
			pm_test_level = level;
			error = 0;
			break;
		}

	unlock_system_sleep();

	return error ? error : n;
}

power_attr(pm_test);
#endif /* CONFIG_PM_DEBUG */

#ifdef CONFIG_DEBUG_FS
static char *suspend_step_name(enum suspend_stat_step step)
{
	switch (step) {
	case SUSPEND_FREEZE:
		return "freeze";
	case SUSPEND_PREPARE:
		return "prepare";
	case SUSPEND_SUSPEND:
		return "suspend";
	case SUSPEND_SUSPEND_NOIRQ:
		return "suspend_noirq";
	case SUSPEND_RESUME_NOIRQ:
		return "resume_noirq";
	case SUSPEND_RESUME:
		return "resume";
	default:
		return "";
	}
}

static int suspend_stats_show(struct seq_file *s, void *unused)
{
	int i, index, last_dev, last_errno, last_step;

	last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
	last_dev %= REC_FAILED_NUM;
	last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
	last_errno %= REC_FAILED_NUM;
	last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
	last_step %= REC_FAILED_NUM;
	seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
			"%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
			"success", suspend_stats.success,
			"fail", suspend_stats.fail,
			"failed_freeze", suspend_stats.failed_freeze,
			"failed_prepare", suspend_stats.failed_prepare,
			"failed_suspend", suspend_stats.failed_suspend,
			"failed_suspend_late",
				suspend_stats.failed_suspend_late,
			"failed_suspend_noirq",
				suspend_stats.failed_suspend_noirq,
			"failed_resume", suspend_stats.failed_resume,
			"failed_resume_early",
				suspend_stats.failed_resume_early,
			"failed_resume_noirq",
				suspend_stats.failed_resume_noirq);
	seq_printf(s,	"failures:\n  last_failed_dev:\t%-s\n",
			suspend_stats.failed_devs[last_dev]);
	for (i = 1; i < REC_FAILED_NUM; i++) {
		index = last_dev + REC_FAILED_NUM - i;
		index %= REC_FAILED_NUM;
		seq_printf(s, "\t\t\t%-s\n",
			suspend_stats.failed_devs[index]);
	}
	seq_printf(s,	"  last_failed_errno:\t%-d\n",
			suspend_stats.errno[last_errno]);
	for (i = 1; i < REC_FAILED_NUM; i++) {
		index = last_errno + REC_FAILED_NUM - i;
		index %= REC_FAILED_NUM;
		seq_printf(s, "\t\t\t%-d\n",
			suspend_stats.errno[index]);
	}
	seq_printf(s,	"  last_failed_step:\t%-s\n",
			suspend_step_name(
				suspend_stats.failed_steps[last_step]));
	for (i = 1; i < REC_FAILED_NUM; i++) {
		index = last_step + REC_FAILED_NUM - i;
		index %= REC_FAILED_NUM;
		seq_printf(s, "\t\t\t%-s\n",
			suspend_step_name(
				suspend_stats.failed_steps[index]));
	}

	return 0;
}

static int suspend_stats_open(struct inode *inode, struct file *file)
{
	return single_open(file, suspend_stats_show, NULL);
}

static const struct file_operations suspend_stats_operations = {
	.open           = suspend_stats_open,
	.read           = seq_read,
	.llseek         = seq_lseek,
	.release        = single_release,
};

static int __init pm_debugfs_init(void)
{
	debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
			NULL, NULL, &suspend_stats_operations);
	return 0;
}

late_initcall(pm_debugfs_init);
#endif /* CONFIG_DEBUG_FS */

#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_PM_SLEEP_DEBUG
/*
 * pm_print_times: print time taken by devices to suspend and resume.
 *
 * show() returns whether printing of suspend and resume times is enabled.
 * store() accepts 0 or 1.  0 disables printing and 1 enables it.
 */
bool pm_print_times_enabled;

static ssize_t pm_print_times_show(struct kobject *kobj,
				   struct kobj_attribute *attr, char *buf)
{
	return sprintf(buf, "%d\n", pm_print_times_enabled);
}

static ssize_t pm_print_times_store(struct kobject *kobj,
				    struct kobj_attribute *attr,
				    const char *buf, size_t n)
{
	unsigned long val;

	if (kstrtoul(buf, 10, &val))
		return -EINVAL;

	if (val > 1)
		return -EINVAL;

	pm_print_times_enabled = !!val;
	return n;
}

power_attr(pm_print_times);

static inline void pm_print_times_init(void)
{
	pm_print_times_enabled = !!initcall_debug;
}

static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
					struct kobj_attribute *attr,
					char *buf)
{
	return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA;
}

power_attr_ro(pm_wakeup_irq);

#else /* !CONFIG_PM_SLEEP_DEBUG */
static inline void pm_print_times_init(void) {}
#endif /* CONFIG_PM_SLEEP_DEBUG */

struct kobject *power_kobj;

/**
 * state - control system sleep states.
 *
 * show() returns available sleep state labels, which may be "mem", "standby",
 * "freeze" and "disk" (hibernation).  See Documentation/power/states.txt for a
 * description of what they mean.
 *
 * store() accepts one of those strings, translates it into the proper
 * enumerated value, and initiates a suspend transition.
 */
static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
			  char *buf)
{
	char *s = buf;
#ifdef CONFIG_SUSPEND
	suspend_state_t i;

	for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
		if (pm_states[i])
			s += sprintf(s,"%s ", pm_states[i]);

#endif
	if (hibernation_available())
		s += sprintf(s, "disk ");
	if (s != buf)
		/* convert the last space to a newline */
		*(s-1) = '\n';
	return (s - buf);
}

static suspend_state_t decode_state(const char *buf, size_t n)
{
#ifdef CONFIG_SUSPEND
	suspend_state_t state;
#endif
	char *p;
	int len;

	p = memchr(buf, '\n', n);
	len = p ? p - buf : n;

	/* Check hibernation first. */
	if (len == 4 && !strncmp(buf, "disk", len))
		return PM_SUSPEND_MAX;

#ifdef CONFIG_SUSPEND
	for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
		const char *label = pm_states[state];

		if (label && len == strlen(label) && !strncmp(buf, label, len))
			return state;
	}
#endif

	return PM_SUSPEND_ON;
}

static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
			   const char *buf, size_t n)
{
	suspend_state_t state;
	int error;

	error = pm_autosleep_lock();
	if (error)
		return error;

	if (pm_autosleep_state() > PM_SUSPEND_ON) {
		error = -EBUSY;
		goto out;
	}

	state = decode_state(buf, n);
	if (state < PM_SUSPEND_MAX)
		error = pm_suspend(state);
	else if (state == PM_SUSPEND_MAX)
		error = hibernate();
	else
		error = -EINVAL;

 out:
	pm_autosleep_unlock();
	return error ? error : n;
}

power_attr(state);

#ifdef CONFIG_PM_SLEEP
/*
 * The 'wakeup_count' attribute, along with the functions defined in
 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
 * handled in a non-racy way.
 *
 * If a wakeup event occurs when the system is in a sleep state, it simply is
 * woken up.  In turn, if an event that would wake the system up from a sleep
 * state occurs when it is undergoing a transition to that sleep state, the
 * transition should be aborted.  Moreover, if such an event occurs when the
 * system is in the working state, an attempt to start a transition to the
 * given sleep state should fail during certain period after the detection of
 * the event.  Using the 'state' attribute alone is not sufficient to satisfy
 * these requirements, because a wakeup event may occur exactly when 'state'
 * is being written to and may be delivered to user space right before it is
 * frozen, so the event will remain only partially processed until the system is
 * woken up by another event.  In particular, it won't cause the transition to
 * a sleep state to be aborted.
 *
 * This difficulty may be overcome if user space uses 'wakeup_count' before
 * writing to 'state'.  It first should read from 'wakeup_count' and store
 * the read value.  Then, after carrying out its own preparations for the system
 * transition to a sleep state, it should write the stored value to
 * 'wakeup_count'.  If that fails, at least one wakeup event has occurred since
 * 'wakeup_count' was read and 'state' should not be written to.  Otherwise, it
 * is allowed to write to 'state', but the transition will be aborted if there
 * are any wakeup events detected after 'wakeup_count' was written to.
 */

static ssize_t wakeup_count_show(struct kobject *kobj,
				struct kobj_attribute *attr,
				char *buf)
{
	unsigned int val;

	return pm_get_wakeup_count(&val, true) ?
		sprintf(buf, "%u\n", val) : -EINTR;
}

static ssize_t wakeup_count_store(struct kobject *kobj,
				struct kobj_attribute *attr,
				const char *buf, size_t n)
{
	unsigned int val;
	int error;

	error = pm_autosleep_lock();
	if (error)
		return error;

	if (pm_autosleep_state() > PM_SUSPEND_ON) {
		error = -EBUSY;
		goto out;
	}

	error = -EINVAL;
	if (sscanf(buf, "%u", &val) == 1) {
		if (pm_save_wakeup_count(val))
			error = n;
		else
			pm_print_active_wakeup_sources();
	}

 out:
	pm_autosleep_unlock();
	return error;
}

power_attr(wakeup_count);

#ifdef CONFIG_PM_AUTOSLEEP
static ssize_t autosleep_show(struct kobject *kobj,
			      struct kobj_attribute *attr,
			      char *buf)
{
	suspend_state_t state = pm_autosleep_state();

	if (state == PM_SUSPEND_ON)
		return sprintf(buf, "off\n");

#ifdef CONFIG_SUSPEND
	if (state < PM_SUSPEND_MAX)
		return sprintf(buf, "%s\n", pm_states[state] ?
					pm_states[state] : "error");
#endif
#ifdef CONFIG_HIBERNATION
	return sprintf(buf, "disk\n");
#else
	return sprintf(buf, "error");
#endif
}

static ssize_t autosleep_store(struct kobject *kobj,
			       struct kobj_attribute *attr,
			       const char *buf, size_t n)
{
	suspend_state_t state = decode_state(buf, n);
	int error;

	if (state == PM_SUSPEND_ON
	    && strcmp(buf, "off") && strcmp(buf, "off\n"))
		return -EINVAL;

	error = pm_autosleep_set_state(state);
	return error ? error : n;
}

power_attr(autosleep);
#endif /* CONFIG_PM_AUTOSLEEP */

#ifdef CONFIG_PM_WAKELOCKS
static ssize_t wake_lock_show(struct kobject *kobj,
			      struct kobj_attribute *attr,
			      char *buf)
{
	return pm_show_wakelocks(buf, true);
}

static ssize_t wake_lock_store(struct kobject *kobj,
			       struct kobj_attribute *attr,
			       const char *buf, size_t n)
{
	int error = pm_wake_lock(buf);
	return error ? error : n;
}

power_attr(wake_lock);

static ssize_t wake_unlock_show(struct kobject *kobj,
				struct kobj_attribute *attr,
				char *buf)
{
	return pm_show_wakelocks(buf, false);
}

static ssize_t wake_unlock_store(struct kobject *kobj,
				 struct kobj_attribute *attr,
				 const char *buf, size_t n)
{
	int error = pm_wake_unlock(buf);
	return error ? error : n;
}

power_attr(wake_unlock);

#endif /* CONFIG_PM_WAKELOCKS */
#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_PM_TRACE
int pm_trace_enabled;

static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
			     char *buf)
{
	return sprintf(buf, "%d\n", pm_trace_enabled);
}

static ssize_t
pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
	       const char *buf, size_t n)
{
	int val;

	if (sscanf(buf, "%d", &val) == 1) {
		pm_trace_enabled = !!val;
		if (pm_trace_enabled) {
			pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
				"PM: Correct system time has to be restored manually after resume.\n");
		}
		return n;
	}
	return -EINVAL;
}

power_attr(pm_trace);

static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
				       struct kobj_attribute *attr,
				       char *buf)
{
	return show_trace_dev_match(buf, PAGE_SIZE);
}

power_attr_ro(pm_trace_dev_match);

#endif /* CONFIG_PM_TRACE */

#ifdef CONFIG_FREEZER
static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
				      struct kobj_attribute *attr, char *buf)
{
	return sprintf(buf, "%u\n", freeze_timeout_msecs);
}

static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
				       struct kobj_attribute *attr,
				       const char *buf, size_t n)
{
	unsigned long val;

	if (kstrtoul(buf, 10, &val))
		return -EINVAL;

	freeze_timeout_msecs = val;
	return n;
}

power_attr(pm_freeze_timeout);

#endif	/* CONFIG_FREEZER*/

static struct attribute * g[] = {
	&state_attr.attr,
#ifdef CONFIG_PM_TRACE
	&pm_trace_attr.attr,
	&pm_trace_dev_match_attr.attr,
#endif
#ifdef CONFIG_PM_SLEEP
	&pm_async_attr.attr,
	&wakeup_count_attr.attr,
#ifdef CONFIG_PM_AUTOSLEEP
	&autosleep_attr.attr,
#endif
#ifdef CONFIG_PM_WAKELOCKS
	&wake_lock_attr.attr,
	&wake_unlock_attr.attr,
#endif
#ifdef CONFIG_PM_DEBUG
	&pm_test_attr.attr,
#endif
#ifdef CONFIG_PM_SLEEP_DEBUG
	&pm_print_times_attr.attr,
	&pm_wakeup_irq_attr.attr,
#endif
#endif
#ifdef CONFIG_FREEZER
	&pm_freeze_timeout_attr.attr,
#endif
	NULL,
};

static struct attribute_group attr_group = {
	.attrs = g,
};

struct workqueue_struct *pm_wq;
EXPORT_SYMBOL_GPL(pm_wq);

static int __init pm_start_workqueue(void)
{
	pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);

	return pm_wq ? 0 : -ENOMEM;
}

static int __init pm_init(void)
{
	int error = pm_start_workqueue();
	if (error)
		return error;
	hibernate_image_size_init();
	hibernate_reserved_size_init();
	power_kobj = kobject_create_and_add("power", NULL);
	if (!power_kobj)
		return -ENOMEM;
	error = sysfs_create_group(power_kobj, &attr_group);
	if (error)
		return error;
	pm_print_times_init();
	return pm_autosleep_init();
}

core_initcall(pm_init);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* kernel/power/main.c - PM subsystem core functionality.
	3	*
	4	* Copyright (c) 2003 Patrick Mochel
	5	* Copyright (c) 2003 Open Source Development Lab
341d4166	6	*
1da177e4 LT	7	* This file is released under the GPLv2
	8	*
	9	*/
	10
6e5fdeed	11	#include <linux/export.h>
1da177e4 LT	12	#include <linux/kobject.h>
1da177e4 LT	13	#include <linux/string.h>
431d452a	14	#include <linux/pm-trace.h>
5e928f77	15	#include <linux/workqueue.h>
2a77c46d SL	16	#include <linux/debugfs.h>
2a77c46d SL	17	#include <linux/seq_file.h>
1da177e4 LT	18
	19	#include "power.h"
	20
a6d70980	21	DEFINE_MUTEX(pm_mutex);
1da177e4	22
cd51e61c RW	23	#ifdef CONFIG_PM_SLEEP
cd51e61c RW	24
82525756 AS	25	/* Routines for PM-transition notifications */
	26
	27	static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
	28
	29	int register_pm_notifier(struct notifier_block *nb)
	30	{
	31	return blocking_notifier_chain_register(&pm_chain_head, nb);
	32	}
	33	EXPORT_SYMBOL_GPL(register_pm_notifier);
	34
	35	int unregister_pm_notifier(struct notifier_block *nb)
	36	{
	37	return blocking_notifier_chain_unregister(&pm_chain_head, nb);
	38	}
	39	EXPORT_SYMBOL_GPL(unregister_pm_notifier);
	40
ea00f4f4	41	int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
82525756	42	{
ea00f4f4 LW	43	int ret;
	44
	45	ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
	46	nr_to_call, nr_calls);
f0c077a8 AM	47
f0c077a8 AM	48	return notifier_to_errno(ret);
82525756	49	}
ea00f4f4 LW	50	int pm_notifier_call_chain(unsigned long val)
	51	{
	52	return __pm_notifier_call_chain(val, -1, NULL);
	53	}
82525756	54
0e06b4a8 RW	55	/* If set, devices may be suspended and resumed asynchronously. */
	56	int pm_async_enabled = 1;
	57
	58	static ssize_t pm_async_show(struct kobject kobj, struct kobj_attribute attr,
	59	char *buf)
	60	{
	61	return sprintf(buf, "%d\n", pm_async_enabled);
	62	}
	63
	64	static ssize_t pm_async_store(struct kobject kobj, struct kobj_attribute attr,
	65	const char *buf, size_t n)
	66	{
	67	unsigned long val;
	68
883ee4f7	69	if (kstrtoul(buf, 10, &val))
0e06b4a8 RW	70	return -EINVAL;
	71
	72	if (val > 1)
	73	return -EINVAL;
	74
	75	pm_async_enabled = val;
	76	return n;
	77	}
	78
	79	power_attr(pm_async);
	80
0e7d56e3 RW	81	#ifdef CONFIG_PM_DEBUG
	82	int pm_test_level = TEST_NONE;
	83
0e7d56e3 RW	84	static const char * const pm_tests[__TEST_AFTER_LAST] = {
	85	[TEST_NONE] = "none",
	86	[TEST_CORE] = "core",
	87	[TEST_CPUS] = "processors",
	88	[TEST_PLATFORM] = "platform",
	89	[TEST_DEVICES] = "devices",
	90	[TEST_FREEZER] = "freezer",
	91	};
	92
039a75c6 RW	93	static ssize_t pm_test_show(struct kobject kobj, struct kobj_attribute attr,
039a75c6 RW	94	char *buf)
0e7d56e3 RW	95	{
	96	char *s = buf;
	97	int level;
	98
	99	for (level = TEST_FIRST; level <= TEST_MAX; level++)
	100	if (pm_tests[level]) {
	101	if (level == pm_test_level)
	102	s += sprintf(s, "[%s] ", pm_tests[level]);
	103	else
	104	s += sprintf(s, "%s ", pm_tests[level]);
	105	}
	106
	107	if (s != buf)
	108	/* convert the last space to a newline */
	109	*(s-1) = '\n';
	110
	111	return (s - buf);
	112	}
	113
039a75c6 RW	114	static ssize_t pm_test_store(struct kobject kobj, struct kobj_attribute attr,
039a75c6 RW	115	const char *buf, size_t n)
0e7d56e3 RW	116	{
	117	const char * const *s;
	118	int level;
	119	char *p;
	120	int len;
	121	int error = -EINVAL;
	122
	123	p = memchr(buf, '\n', n);
	124	len = p ? p - buf : n;
	125
bcda53fa	126	lock_system_sleep();
0e7d56e3 RW	127
	128	level = TEST_FIRST;
	129	for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
	130	if (s && len == strlen(s) && !strncmp(buf, *s, len)) {
	131	pm_test_level = level;
	132	error = 0;
	133	break;
	134	}
	135
bcda53fa	136	unlock_system_sleep();
0e7d56e3 RW	137
	138	return error ? error : n;
	139	}
	140
	141	power_attr(pm_test);
091d71e0	142	#endif /* CONFIG_PM_DEBUG */
0e7d56e3	143
2a77c46d SL	144	#ifdef CONFIG_DEBUG_FS
	145	static char *suspend_step_name(enum suspend_stat_step step)
	146	{
	147	switch (step) {
	148	case SUSPEND_FREEZE:
	149	return "freeze";
	150	case SUSPEND_PREPARE:
	151	return "prepare";
	152	case SUSPEND_SUSPEND:
	153	return "suspend";
	154	case SUSPEND_SUSPEND_NOIRQ:
	155	return "suspend_noirq";
	156	case SUSPEND_RESUME_NOIRQ:
	157	return "resume_noirq";
	158	case SUSPEND_RESUME:
	159	return "resume";
	160	default:
	161	return "";
	162	}
	163	}
	164
	165	static int suspend_stats_show(struct seq_file s, void unused)
	166	{
	167	int i, index, last_dev, last_errno, last_step;
	168
	169	last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
	170	last_dev %= REC_FAILED_NUM;
	171	last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
	172	last_errno %= REC_FAILED_NUM;
	173	last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
	174	last_step %= REC_FAILED_NUM;
cf579dfb RW	175	seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
cf579dfb RW	176	"%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
2a77c46d SL	177	"success", suspend_stats.success,
	178	"fail", suspend_stats.fail,
	179	"failed_freeze", suspend_stats.failed_freeze,
	180	"failed_prepare", suspend_stats.failed_prepare,
	181	"failed_suspend", suspend_stats.failed_suspend,
cf579dfb RW	182	"failed_suspend_late",
cf579dfb RW	183	suspend_stats.failed_suspend_late,
2a77c46d SL	184	"failed_suspend_noirq",
	185	suspend_stats.failed_suspend_noirq,
	186	"failed_resume", suspend_stats.failed_resume,
cf579dfb RW	187	"failed_resume_early",
cf579dfb RW	188	suspend_stats.failed_resume_early,
2a77c46d SL	189	"failed_resume_noirq",
	190	suspend_stats.failed_resume_noirq);
	191	seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
	192	suspend_stats.failed_devs[last_dev]);
	193	for (i = 1; i < REC_FAILED_NUM; i++) {
	194	index = last_dev + REC_FAILED_NUM - i;
	195	index %= REC_FAILED_NUM;
	196	seq_printf(s, "\t\t\t%-s\n",
	197	suspend_stats.failed_devs[index]);
	198	}
	199	seq_printf(s, " last_failed_errno:\t%-d\n",
	200	suspend_stats.errno[last_errno]);
	201	for (i = 1; i < REC_FAILED_NUM; i++) {
	202	index = last_errno + REC_FAILED_NUM - i;
	203	index %= REC_FAILED_NUM;
	204	seq_printf(s, "\t\t\t%-d\n",
	205	suspend_stats.errno[index]);
	206	}
	207	seq_printf(s, " last_failed_step:\t%-s\n",
	208	suspend_step_name(
	209	suspend_stats.failed_steps[last_step]));
	210	for (i = 1; i < REC_FAILED_NUM; i++) {
	211	index = last_step + REC_FAILED_NUM - i;
	212	index %= REC_FAILED_NUM;
	213	seq_printf(s, "\t\t\t%-s\n",
	214	suspend_step_name(
	215	suspend_stats.failed_steps[index]));
	216	}
	217
	218	return 0;
	219	}
	220
	221	static int suspend_stats_open(struct inode inode, struct file file)
	222	{
	223	return single_open(file, suspend_stats_show, NULL);
	224	}
	225
	226	static const struct file_operations suspend_stats_operations = {
	227	.open = suspend_stats_open,
	228	.read = seq_read,
	229	.llseek = seq_lseek,
	230	.release = single_release,
	231	};
	232
	233	static int __init pm_debugfs_init(void)
	234	{
	235	debugfs_create_file("suspend_stats", S_IFREG \| S_IRUGO,
	236	NULL, NULL, &suspend_stats_operations);
	237	return 0;
	238	}
	239
	240	late_initcall(pm_debugfs_init);
	241	#endif /* CONFIG_DEBUG_FS */
	242
ca123102 RW	243	#endif /* CONFIG_PM_SLEEP */
ca123102 RW	244
b2df1d4f RW	245	#ifdef CONFIG_PM_SLEEP_DEBUG
	246	/*
	247	* pm_print_times: print time taken by devices to suspend and resume.
	248	*
	249	* show() returns whether printing of suspend and resume times is enabled.
	250	* store() accepts 0 or 1. 0 disables printing and 1 enables it.
	251	*/
	252	bool pm_print_times_enabled;
	253
	254	static ssize_t pm_print_times_show(struct kobject *kobj,
	255	struct kobj_attribute attr, char buf)
	256	{
	257	return sprintf(buf, "%d\n", pm_print_times_enabled);
	258	}
	259
	260	static ssize_t pm_print_times_store(struct kobject *kobj,
	261	struct kobj_attribute *attr,
	262	const char *buf, size_t n)
	263	{
	264	unsigned long val;
	265
	266	if (kstrtoul(buf, 10, &val))
	267	return -EINVAL;
	268
	269	if (val > 1)
	270	return -EINVAL;
	271
	272	pm_print_times_enabled = !!val;
	273	return n;
	274	}
	275
	276	power_attr(pm_print_times);
	277
	278	static inline void pm_print_times_init(void)
	279	{
	280	pm_print_times_enabled = !!initcall_debug;
	281	}
a6f5f0dd AY	282
	283	static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
	284	struct kobj_attribute *attr,
	285	char *buf)
	286	{
	287	return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA;
	288	}
	289
a1e9ca69	290	power_attr_ro(pm_wakeup_irq);
a6f5f0dd	291
819b1bb3	292	#else /* !CONFIG_PM_SLEEP_DEBUG */
b2df1d4f RW	293	static inline void pm_print_times_init(void) {}
	294	#endif /* CONFIG_PM_SLEEP_DEBUG */
	295
d76e15fb	296	struct kobject *power_kobj;
1da177e4 LT	297
1da177e4 LT	298	/**
0399d4db	299	* state - control system sleep states.
1da177e4	300	*
0399d4db RW	301	* show() returns available sleep state labels, which may be "mem", "standby",
	302	* "freeze" and "disk" (hibernation). See Documentation/power/states.txt for a
	303	* description of what they mean.
1da177e4	304	*
0399d4db RW	305	* store() accepts one of those strings, translates it into the proper
0399d4db RW	306	* enumerated value, and initiates a suspend transition.
1da177e4	307	*/
386f275f KS	308	static ssize_t state_show(struct kobject kobj, struct kobj_attribute attr,
386f275f KS	309	char *buf)
1da177e4	310	{
296699de RW	311	char *s = buf;
296699de RW	312	#ifdef CONFIG_SUSPEND
27ddcc65 RW	313	suspend_state_t i;
	314
	315	for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
d431cbc5 RW	316	if (pm_states[i])
d431cbc5 RW	317	s += sprintf(s,"%s ", pm_states[i]);
1da177e4	318
296699de	319	#endif
a6e15a39 KC	320	if (hibernation_available())
a6e15a39 KC	321	s += sprintf(s, "disk ");
a3d25c27 RW	322	if (s != buf)
	323	/* convert the last space to a newline */
	324	*(s-1) = '\n';
1da177e4 LT	325	return (s - buf);
	326	}
	327
7483b4a4	328	static suspend_state_t decode_state(const char *buf, size_t n)
1da177e4	329	{
296699de	330	#ifdef CONFIG_SUSPEND
d431cbc5	331	suspend_state_t state;
296699de	332	#endif
1da177e4	333	char *p;
1da177e4 LT	334	int len;
	335
	336	p = memchr(buf, '\n', n);
	337	len = p ? p - buf : n;
	338
7483b4a4 RW	339	/* Check hibernation first. */
	340	if (len == 4 && !strncmp(buf, "disk", len))
	341	return PM_SUSPEND_MAX;
a3d25c27	342
296699de	343	#ifdef CONFIG_SUSPEND
d431cbc5 RW	344	for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
	345	const char *label = pm_states[state];
	346
	347	if (label && len == strlen(label) && !strncmp(buf, label, len))
	348	return state;
	349	}
296699de RW	350	#endif
296699de RW	351
7483b4a4 RW	352	return PM_SUSPEND_ON;
	353	}
	354
	355	static ssize_t state_store(struct kobject kobj, struct kobj_attribute attr,
	356	const char *buf, size_t n)
	357	{
	358	suspend_state_t state;
	359	int error;
	360
	361	error = pm_autosleep_lock();
	362	if (error)
	363	return error;
	364
	365	if (pm_autosleep_state() > PM_SUSPEND_ON) {
	366	error = -EBUSY;
	367	goto out;
	368	}
	369
	370	state = decode_state(buf, n);
	371	if (state < PM_SUSPEND_MAX)
	372	error = pm_suspend(state);
	373	else if (state == PM_SUSPEND_MAX)
	374	error = hibernate();
	375	else
	376	error = -EINVAL;
	377
	378	out:
	379	pm_autosleep_unlock();
1da177e4 LT	380	return error ? error : n;
	381	}
	382
	383	power_attr(state);
	384
c125e96f RW	385	#ifdef CONFIG_PM_SLEEP
	386	/*
	387	* The 'wakeup_count' attribute, along with the functions defined in
	388	* drivers/base/power/wakeup.c, provides a means by which wakeup events can be
	389	* handled in a non-racy way.
	390	*
	391	* If a wakeup event occurs when the system is in a sleep state, it simply is
	392	* woken up. In turn, if an event that would wake the system up from a sleep
	393	* state occurs when it is undergoing a transition to that sleep state, the
	394	* transition should be aborted. Moreover, if such an event occurs when the
	395	* system is in the working state, an attempt to start a transition to the
	396	* given sleep state should fail during certain period after the detection of
	397	* the event. Using the 'state' attribute alone is not sufficient to satisfy
	398	* these requirements, because a wakeup event may occur exactly when 'state'
	399	* is being written to and may be delivered to user space right before it is
	400	* frozen, so the event will remain only partially processed until the system is
	401	* woken up by another event. In particular, it won't cause the transition to
	402	* a sleep state to be aborted.
	403	*
	404	* This difficulty may be overcome if user space uses 'wakeup_count' before
	405	* writing to 'state'. It first should read from 'wakeup_count' and store
	406	* the read value. Then, after carrying out its own preparations for the system
	407	* transition to a sleep state, it should write the stored value to
25985edc	408	* 'wakeup_count'. If that fails, at least one wakeup event has occurred since
c125e96f RW	409	* 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
	410	* is allowed to write to 'state', but the transition will be aborted if there
	411	* are any wakeup events detected after 'wakeup_count' was written to.
	412	*/
	413
	414	static ssize_t wakeup_count_show(struct kobject *kobj,
	415	struct kobj_attribute *attr,
	416	char *buf)
	417	{
074037ec	418	unsigned int val;
c125e96f	419
7483b4a4 RW	420	return pm_get_wakeup_count(&val, true) ?
7483b4a4 RW	421	sprintf(buf, "%u\n", val) : -EINTR;
c125e96f RW	422	}
	423
	424	static ssize_t wakeup_count_store(struct kobject *kobj,
	425	struct kobj_attribute *attr,
	426	const char *buf, size_t n)
	427	{
074037ec	428	unsigned int val;
7483b4a4 RW	429	int error;
	430
	431	error = pm_autosleep_lock();
	432	if (error)
	433	return error;
c125e96f	434
7483b4a4 RW	435	if (pm_autosleep_state() > PM_SUSPEND_ON) {
	436	error = -EBUSY;
	437	goto out;
	438	}
	439
	440	error = -EINVAL;
074037ec	441	if (sscanf(buf, "%u", &val) == 1) {
c125e96f	442	if (pm_save_wakeup_count(val))
7483b4a4	443	error = n;
bb177fed JW	444	else
bb177fed JW	445	pm_print_active_wakeup_sources();
c125e96f	446	}
7483b4a4 RW	447
	448	out:
	449	pm_autosleep_unlock();
	450	return error;
c125e96f RW	451	}
	452
	453	power_attr(wakeup_count);
7483b4a4 RW	454
	455	#ifdef CONFIG_PM_AUTOSLEEP
	456	static ssize_t autosleep_show(struct kobject *kobj,
	457	struct kobj_attribute *attr,
	458	char *buf)
	459	{
	460	suspend_state_t state = pm_autosleep_state();
	461
	462	if (state == PM_SUSPEND_ON)
	463	return sprintf(buf, "off\n");
	464
	465	#ifdef CONFIG_SUSPEND
	466	if (state < PM_SUSPEND_MAX)
d431cbc5 RW	467	return sprintf(buf, "%s\n", pm_states[state] ?
d431cbc5 RW	468	pm_states[state] : "error");
7483b4a4 RW	469	#endif
	470	#ifdef CONFIG_HIBERNATION
	471	return sprintf(buf, "disk\n");
	472	#else
	473	return sprintf(buf, "error");
	474	#endif
	475	}
	476
	477	static ssize_t autosleep_store(struct kobject *kobj,
	478	struct kobj_attribute *attr,
	479	const char *buf, size_t n)
	480	{
	481	suspend_state_t state = decode_state(buf, n);
	482	int error;
	483
	484	if (state == PM_SUSPEND_ON
040e5bf6	485	&& strcmp(buf, "off") && strcmp(buf, "off\n"))
7483b4a4 RW	486	return -EINVAL;
	487
	488	error = pm_autosleep_set_state(state);
	489	return error ? error : n;
	490	}
	491
	492	power_attr(autosleep);
	493	#endif /* CONFIG_PM_AUTOSLEEP */
b86ff982 RW	494
	495	#ifdef CONFIG_PM_WAKELOCKS
	496	static ssize_t wake_lock_show(struct kobject *kobj,
	497	struct kobj_attribute *attr,
	498	char *buf)
	499	{
	500	return pm_show_wakelocks(buf, true);
	501	}
	502
	503	static ssize_t wake_lock_store(struct kobject *kobj,
	504	struct kobj_attribute *attr,
	505	const char *buf, size_t n)
	506	{
	507	int error = pm_wake_lock(buf);
	508	return error ? error : n;
	509	}
	510
	511	power_attr(wake_lock);
	512
	513	static ssize_t wake_unlock_show(struct kobject *kobj,
	514	struct kobj_attribute *attr,
	515	char *buf)
	516	{
	517	return pm_show_wakelocks(buf, false);
	518	}
	519
	520	static ssize_t wake_unlock_store(struct kobject *kobj,
	521	struct kobj_attribute *attr,
	522	const char *buf, size_t n)
	523	{
	524	int error = pm_wake_unlock(buf);
	525	return error ? error : n;
	526	}
	527
	528	power_attr(wake_unlock);
	529
	530	#endif /* CONFIG_PM_WAKELOCKS */
c125e96f RW	531	#endif /* CONFIG_PM_SLEEP */
c125e96f RW	532
c5c6ba4e RW	533	#ifdef CONFIG_PM_TRACE
	534	int pm_trace_enabled;
	535
386f275f KS	536	static ssize_t pm_trace_show(struct kobject kobj, struct kobj_attribute attr,
386f275f KS	537	char *buf)
c5c6ba4e RW	538	{
	539	return sprintf(buf, "%d\n", pm_trace_enabled);
	540	}
	541
	542	static ssize_t
386f275f KS	543	pm_trace_store(struct kobject kobj, struct kobj_attribute attr,
386f275f KS	544	const char *buf, size_t n)
c5c6ba4e RW	545	{
	546	int val;
	547
	548	if (sscanf(buf, "%d", &val) == 1) {
	549	pm_trace_enabled = !!val;
9dceefe4 SK	550	if (pm_trace_enabled) {
	551	pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
	552	"PM: Correct system time has to be restored manually after resume.\n");
	553	}
c5c6ba4e RW	554	return n;
	555	}
	556	return -EINVAL;
	557	}
	558
	559	power_attr(pm_trace);
d33ac60b JH	560
	561	static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
	562	struct kobj_attribute *attr,
	563	char *buf)
	564	{
	565	return show_trace_dev_match(buf, PAGE_SIZE);
	566	}
	567
a1e9ca69	568	power_attr_ro(pm_trace_dev_match);
d33ac60b	569
0e7d56e3	570	#endif /* CONFIG_PM_TRACE */
c5c6ba4e	571
957d1282 LF	572	#ifdef CONFIG_FREEZER
	573	static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
	574	struct kobj_attribute attr, char buf)
	575	{
	576	return sprintf(buf, "%u\n", freeze_timeout_msecs);
	577	}
	578
	579	static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
	580	struct kobj_attribute *attr,
	581	const char *buf, size_t n)
	582	{
	583	unsigned long val;
	584
	585	if (kstrtoul(buf, 10, &val))
	586	return -EINVAL;
	587
	588	freeze_timeout_msecs = val;
	589	return n;
	590	}
	591
	592	power_attr(pm_freeze_timeout);
	593
	594	#endif /* CONFIG_FREEZER*/
	595
c5c6ba4e RW	596	static struct attribute * g[] = {
c5c6ba4e RW	597	&state_attr.attr,
0e7d56e3	598	#ifdef CONFIG_PM_TRACE
c5c6ba4e	599	&pm_trace_attr.attr,
d33ac60b	600	&pm_trace_dev_match_attr.attr,
0e7d56e3	601	#endif
0e06b4a8 RW	602	#ifdef CONFIG_PM_SLEEP
0e06b4a8 RW	603	&pm_async_attr.attr,
c125e96f	604	&wakeup_count_attr.attr,
7483b4a4 RW	605	#ifdef CONFIG_PM_AUTOSLEEP
	606	&autosleep_attr.attr,
	607	#endif
b86ff982 RW	608	#ifdef CONFIG_PM_WAKELOCKS
	609	&wake_lock_attr.attr,
	610	&wake_unlock_attr.attr,
	611	#endif
0e06b4a8	612	#ifdef CONFIG_PM_DEBUG
0e7d56e3	613	&pm_test_attr.attr,
b2df1d4f RW	614	#endif
b2df1d4f RW	615	#ifdef CONFIG_PM_SLEEP_DEBUG
4b7760ba	616	&pm_print_times_attr.attr,
a6f5f0dd	617	&pm_wakeup_irq_attr.attr,
0e06b4a8	618	#endif
957d1282 LF	619	#endif
	620	#ifdef CONFIG_FREEZER
	621	&pm_freeze_timeout_attr.attr,
0e7d56e3	622	#endif
c5c6ba4e RW	623	NULL,
c5c6ba4e RW	624	};
1da177e4 LT	625
	626	static struct attribute_group attr_group = {
	627	.attrs = g,
	628	};
	629
5e928f77	630	struct workqueue_struct *pm_wq;
7b199ca2	631	EXPORT_SYMBOL_GPL(pm_wq);
5e928f77 RW	632
	633	static int __init pm_start_workqueue(void)
	634	{
58a69cb4	635	pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
5e928f77 RW	636
	637	return pm_wq ? 0 : -ENOMEM;
	638	}
5e928f77	639
1da177e4 LT	640	static int __init pm_init(void)
1da177e4 LT	641	{
5e928f77 RW	642	int error = pm_start_workqueue();
	643	if (error)
	644	return error;
ac5c24ec	645	hibernate_image_size_init();
ddeb6487	646	hibernate_reserved_size_init();
d76e15fb GKH	647	power_kobj = kobject_create_and_add("power", NULL);
d76e15fb GKH	648	if (!power_kobj)
039a5dcd	649	return -ENOMEM;
7483b4a4 RW	650	error = sysfs_create_group(power_kobj, &attr_group);
	651	if (error)
	652	return error;
b2df1d4f	653	pm_print_times_init();
7483b4a4	654	return pm_autosleep_init();
1da177e4 LT	655	}
	656
	657	core_initcall(pm_init);