--- /dev/null
+/*
+ * 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 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);
Code Review / kvmfornfv.git / blobdiff