| /* |
| * 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/resume-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 ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL); |
| |
| return notifier_to_errno(ret); |
| } |
| |
| /* 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; |
| } |
| #else /* !CONFIG_PP_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); |
| } |
| |
| static ssize_t |
| pm_trace_dev_match_store(struct kobject *kobj, struct kobj_attribute *attr, |
| const char *buf, size_t n) |
| { |
| return -EINVAL; |
| } |
| |
| power_attr(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, |
| #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); |