| /* |
| * 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/kobject.h> |
| #include <linux/string.h> |
| #include <linux/resume-trace.h> |
| #include <linux/workqueue.h> |
| |
| #include "power.h" |
| |
| DEFINE_MUTEX(pm_mutex); |
| |
| unsigned int pm_flags; |
| EXPORT_SYMBOL(pm_flags); |
| |
| #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) |
| { |
| return (blocking_notifier_call_chain(&pm_chain_head, val, NULL) |
| == NOTIFY_BAD) ? -EINVAL : 0; |
| } |
| |
| /* 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 (strict_strtoul(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; |
| |
| mutex_lock(&pm_mutex); |
| |
| 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; |
| } |
| |
| mutex_unlock(&pm_mutex); |
| |
| return error ? error : n; |
| } |
| |
| power_attr(pm_test); |
| #endif /* CONFIG_PM_DEBUG */ |
| |
| #endif /* CONFIG_PM_SLEEP */ |
| |
| struct kobject *power_kobj; |
| |
| /** |
| * state - control system power state. |
| * |
| * show() returns what states are supported, which is hard-coded to |
| * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and |
| * 'disk' (Suspend-to-Disk). |
| * |
| * 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 |
| int i; |
| |
| for (i = 0; i < PM_SUSPEND_MAX; i++) { |
| if (pm_states[i] && valid_state(i)) |
| s += sprintf(s,"%s ", pm_states[i]); |
| } |
| #endif |
| #ifdef CONFIG_HIBERNATION |
| s += sprintf(s, "%s\n", "disk"); |
| #else |
| if (s != buf) |
| /* convert the last space to a newline */ |
| *(s-1) = '\n'; |
| #endif |
| return (s - buf); |
| } |
| |
| static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, |
| const char *buf, size_t n) |
| { |
| #ifdef CONFIG_SUSPEND |
| suspend_state_t state = PM_SUSPEND_STANDBY; |
| const char * const *s; |
| #endif |
| char *p; |
| int len; |
| int error = -EINVAL; |
| |
| p = memchr(buf, '\n', n); |
| len = p ? p - buf : n; |
| |
| /* First, check if we are requested to hibernate */ |
| if (len == 4 && !strncmp(buf, "disk", len)) { |
| error = hibernate(); |
| goto Exit; |
| } |
| |
| #ifdef CONFIG_SUSPEND |
| for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
| if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) |
| break; |
| } |
| if (state < PM_SUSPEND_MAX && *s) |
| error = enter_state(state); |
| #endif |
| |
| Exit: |
| return error ? error : n; |
| } |
| |
| power_attr(state); |
| |
| #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; |
| return n; |
| } |
| return -EINVAL; |
| } |
| |
| power_attr(pm_trace); |
| #endif /* CONFIG_PM_TRACE */ |
| |
| static struct attribute * g[] = { |
| &state_attr.attr, |
| #ifdef CONFIG_PM_TRACE |
| &pm_trace_attr.attr, |
| #endif |
| #ifdef CONFIG_PM_SLEEP |
| &pm_async_attr.attr, |
| #ifdef CONFIG_PM_DEBUG |
| &pm_test_attr.attr, |
| #endif |
| #endif |
| NULL, |
| }; |
| |
| static struct attribute_group attr_group = { |
| .attrs = g, |
| }; |
| |
| #ifdef CONFIG_PM_RUNTIME |
| struct workqueue_struct *pm_wq; |
| EXPORT_SYMBOL_GPL(pm_wq); |
| |
| static int __init pm_start_workqueue(void) |
| { |
| pm_wq = create_freezeable_workqueue("pm"); |
| |
| return pm_wq ? 0 : -ENOMEM; |
| } |
| #else |
| static inline int pm_start_workqueue(void) { return 0; } |
| #endif |
| |
| static int __init pm_init(void) |
| { |
| int error = pm_start_workqueue(); |
| if (error) |
| return error; |
| hibernate_image_size_init(); |
| power_kobj = kobject_create_and_add("power", NULL); |
| if (!power_kobj) |
| return -ENOMEM; |
| return sysfs_create_group(power_kobj, &attr_group); |
| } |
| |
| core_initcall(pm_init); |