linux/kernel/power/main.c
Linus Torvalds 9d004b2f4f cxl for 5.19
- Add driver-core infrastructure for lockdep validation of
   device_lock(), and fixup a deadlock report that was previously hidden
   behind the 'lockdep no validate' policy.
 
 - Add CXL _OSC support for claiming native control of CXL hotplug and
   error handling.
 
 - Disable suspend in the presence of CXL memory unless and until a
   protocol is identified for restoring PCI device context from memory
   hosted on CXL PCI devices.
 
 - Add support for snooping CXL mailbox commands to protect against
   inopportune changes, like set-partition with the 'immediate' flag set.
 
 - Rework how the driver detects legacy CXL 1.1 configurations (CXL DVSEC
   / 'mem_enable') before enabling new CXL 2.0 decode configurations (CXL
   HDM Capability).
 
 - Miscellaneous cleanups and fixes from -next exposure.
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Merge tag 'cxl-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl updates from Dan Williams:
 "Compute Express Link (CXL) updates for this cycle.

  The highlight is new driver-core infrastructure and CXL subsystem
  changes for allowing lockdep to validate device_lock() usage. Thanks
  to PeterZ for setting me straight on the current capabilities of the
  lockdep API, and Greg acked it as well.

  On the CXL ACPI side this update adds support for CXL _OSC so that
  platform firmware knows that it is safe to still grant Linux native
  control of PCIe hotplug and error handling in the presence of CXL
  devices. A circular dependency problem was discovered between suspend
  and CXL memory for cases where the suspend image might be stored in
  CXL memory where that image also contains the PCI register state to
  restore to re-enable the device. Disable suspend for now until an
  architecture is defined to clarify that conflict.

  Lastly a collection of reworks, fixes, and cleanups to the CXL
  subsystem where support for snooping mailbox commands and properly
  handling the "mem_enable" flow are the highlights.

  Summary:

   - Add driver-core infrastructure for lockdep validation of
     device_lock(), and fixup a deadlock report that was previously
     hidden behind the 'lockdep no validate' policy.

   - Add CXL _OSC support for claiming native control of CXL hotplug and
     error handling.

   - Disable suspend in the presence of CXL memory unless and until a
     protocol is identified for restoring PCI device context from memory
     hosted on CXL PCI devices.

   - Add support for snooping CXL mailbox commands to protect against
     inopportune changes, like set-partition with the 'immediate' flag
     set.

   - Rework how the driver detects legacy CXL 1.1 configurations (CXL
     DVSEC / 'mem_enable') before enabling new CXL 2.0 decode
     configurations (CXL HDM Capability).

   - Miscellaneous cleanups and fixes from -next exposure"

* tag 'cxl-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (47 commits)
  cxl/port: Enable HDM Capability after validating DVSEC Ranges
  cxl/port: Reuse 'struct cxl_hdm' context for hdm init
  cxl/port: Move endpoint HDM Decoder Capability init to port driver
  cxl/pci: Drop @info argument to cxl_hdm_decode_init()
  cxl/mem: Merge cxl_dvsec_ranges() and cxl_hdm_decode_init()
  cxl/mem: Skip range enumeration if mem_enable clear
  cxl/mem: Consolidate CXL DVSEC Range enumeration in the core
  cxl/pci: Move cxl_await_media_ready() to the core
  cxl/mem: Validate port connectivity before dvsec ranges
  cxl/mem: Fix cxl_mem_probe() error exit
  cxl/pci: Drop wait_for_valid() from cxl_await_media_ready()
  cxl/pci: Consolidate wait_for_media() and wait_for_media_ready()
  cxl/mem: Drop mem_enabled check from wait_for_media()
  nvdimm: Fix firmware activation deadlock scenarios
  device-core: Kill the lockdep_mutex
  nvdimm: Drop nd_device_lock()
  ACPI: NFIT: Drop nfit_device_lock()
  nvdimm: Replace lockdep_mutex with local lock classes
  cxl: Drop cxl_device_lock()
  cxl/acpi: Add root device lockdep validation
  ...
2022-05-27 21:24:19 -07:00

937 lines
22 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* kernel/power/main.c - PM subsystem core functionality.
*
* Copyright (c) 2003 Patrick Mochel
* Copyright (c) 2003 Open Source Development Lab
*/
#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 <linux/suspend.h>
#include <linux/syscalls.h>
#include <linux/pm_runtime.h>
#include "power.h"
#ifdef CONFIG_PM_SLEEP
void lock_system_sleep(void)
{
current->flags |= PF_FREEZER_SKIP;
mutex_lock(&system_transition_mutex);
}
EXPORT_SYMBOL_GPL(lock_system_sleep);
void unlock_system_sleep(void)
{
/*
* Don't use freezer_count() because we don't want the call to
* try_to_freeze() here.
*
* Reason:
* Fundamentally, we just don't need it, because freezing condition
* doesn't come into effect until we release the
* system_transition_mutex lock, since the freezer always works with
* system_transition_mutex held.
*
* More importantly, in the case of hibernation,
* unlock_system_sleep() gets called in snapshot_read() and
* snapshot_write() when the freezing condition is still in effect.
* Which means, if we use try_to_freeze() here, it would make them
* enter the refrigerator, thus causing hibernation to lockup.
*/
current->flags &= ~PF_FREEZER_SKIP;
mutex_unlock(&system_transition_mutex);
}
EXPORT_SYMBOL_GPL(unlock_system_sleep);
void ksys_sync_helper(void)
{
ktime_t start;
long elapsed_msecs;
start = ktime_get();
ksys_sync();
elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
pr_info("Filesystems sync: %ld.%03ld seconds\n",
elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
}
EXPORT_SYMBOL_GPL(ksys_sync_helper);
/* 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_robust(unsigned long val_up, unsigned long val_down)
{
int ret;
ret = blocking_notifier_call_chain_robust(&pm_chain_head, val_up, val_down, NULL);
return notifier_to_errno(ret);
}
int pm_notifier_call_chain(unsigned long val)
{
return blocking_notifier_call_chain(&pm_chain_head, val, 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_SUSPEND
static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
char *s = buf;
suspend_state_t i;
for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) {
if (i >= PM_SUSPEND_MEM && cxl_mem_active())
continue;
if (mem_sleep_states[i]) {
const char *label = mem_sleep_states[i];
if (mem_sleep_current == i)
s += sprintf(s, "[%s] ", label);
else
s += sprintf(s, "%s ", label);
}
}
/* Convert the last space to a newline if needed. */
if (s != buf)
*(s-1) = '\n';
return (s - buf);
}
static suspend_state_t decode_suspend_state(const char *buf, size_t n)
{
suspend_state_t state;
char *p;
int len;
p = memchr(buf, '\n', n);
len = p ? p - buf : n;
for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
const char *label = mem_sleep_states[state];
if (label && len == strlen(label) && !strncmp(buf, label, len))
return state;
}
return PM_SUSPEND_ON;
}
static ssize_t mem_sleep_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_suspend_state(buf, n);
if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
mem_sleep_current = state;
else
error = -EINVAL;
out:
pm_autosleep_unlock();
return error ? error : n;
}
power_attr(mem_sleep);
/*
* sync_on_suspend: invoke ksys_sync_helper() before suspend.
*
* show() returns whether ksys_sync_helper() is invoked before suspend.
* store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it.
*/
bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC);
static ssize_t sync_on_suspend_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", sync_on_suspend_enabled);
}
static ssize_t sync_on_suspend_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;
sync_on_suspend_enabled = !!val;
return n;
}
power_attr(sync_on_suspend);
#endif /* CONFIG_SUSPEND */
#ifdef CONFIG_PM_SLEEP_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_SLEEP_DEBUG */
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 "";
}
}
#define suspend_attr(_name) \
static ssize_t _name##_show(struct kobject *kobj, \
struct kobj_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%d\n", suspend_stats._name); \
} \
static struct kobj_attribute _name = __ATTR_RO(_name)
suspend_attr(success);
suspend_attr(fail);
suspend_attr(failed_freeze);
suspend_attr(failed_prepare);
suspend_attr(failed_suspend);
suspend_attr(failed_suspend_late);
suspend_attr(failed_suspend_noirq);
suspend_attr(failed_resume);
suspend_attr(failed_resume_early);
suspend_attr(failed_resume_noirq);
static ssize_t last_failed_dev_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
int index;
char *last_failed_dev = NULL;
index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
index %= REC_FAILED_NUM;
last_failed_dev = suspend_stats.failed_devs[index];
return sprintf(buf, "%s\n", last_failed_dev);
}
static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
static ssize_t last_failed_errno_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
int index;
int last_failed_errno;
index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
index %= REC_FAILED_NUM;
last_failed_errno = suspend_stats.errno[index];
return sprintf(buf, "%d\n", last_failed_errno);
}
static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
static ssize_t last_failed_step_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
int index;
enum suspend_stat_step step;
char *last_failed_step = NULL;
index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
index %= REC_FAILED_NUM;
step = suspend_stats.failed_steps[index];
last_failed_step = suspend_step_name(step);
return sprintf(buf, "%s\n", last_failed_step);
}
static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
static struct attribute *suspend_attrs[] = {
&success.attr,
&fail.attr,
&failed_freeze.attr,
&failed_prepare.attr,
&failed_suspend.attr,
&failed_suspend_late.attr,
&failed_suspend_noirq.attr,
&failed_resume.attr,
&failed_resume_early.attr,
&failed_resume_noirq.attr,
&last_failed_dev.attr,
&last_failed_errno.attr,
&last_failed_step.attr,
NULL,
};
static const struct attribute_group suspend_attr_group = {
.name = "suspend_stats",
.attrs = suspend_attrs,
};
#ifdef CONFIG_DEBUG_FS
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;
}
DEFINE_SHOW_ATTRIBUTE(suspend_stats);
static int __init pm_debugfs_init(void)
{
debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
NULL, NULL, &suspend_stats_fops);
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)
{
if (!pm_wakeup_irq())
return -ENODATA;
return sprintf(buf, "%u\n", pm_wakeup_irq());
}
power_attr_ro(pm_wakeup_irq);
bool pm_debug_messages_on __read_mostly;
static ssize_t pm_debug_messages_show(struct kobject *kobj,
struct kobj_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", pm_debug_messages_on);
}
static ssize_t pm_debug_messages_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_debug_messages_on = !!val;
return n;
}
power_attr(pm_debug_messages);
static int __init pm_debug_messages_setup(char *str)
{
pm_debug_messages_on = true;
return 1;
}
__setup("pm_debug_messages", pm_debug_messages_setup);
#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/admin-guide/pm/sleep-states.rst 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 && str_has_prefix(buf, "disk"))
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) {
if (state == PM_SUSPEND_MEM)
state = mem_sleep_current;
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;
if (state == PM_SUSPEND_MEM)
state = mem_sleep_current;
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_SUSPEND
&mem_sleep_attr.attr,
&sync_on_suspend_attr.attr,
#endif
#ifdef CONFIG_PM_AUTOSLEEP
&autosleep_attr.attr,
#endif
#ifdef CONFIG_PM_WAKELOCKS
&wake_lock_attr.attr,
&wake_unlock_attr.attr,
#endif
#ifdef CONFIG_PM_SLEEP_DEBUG
&pm_test_attr.attr,
&pm_print_times_attr.attr,
&pm_wakeup_irq_attr.attr,
&pm_debug_messages_attr.attr,
#endif
#endif
#ifdef CONFIG_FREEZER
&pm_freeze_timeout_attr.attr,
#endif
NULL,
};
static const struct attribute_group attr_group = {
.attrs = g,
};
static const struct attribute_group *attr_groups[] = {
&attr_group,
#ifdef CONFIG_PM_SLEEP
&suspend_attr_group,
#endif
NULL,
};
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();
pm_states_init();
power_kobj = kobject_create_and_add("power", NULL);
if (!power_kobj)
return -ENOMEM;
error = sysfs_create_groups(power_kobj, attr_groups);
if (error)
return error;
pm_print_times_init();
return pm_autosleep_init();
}
core_initcall(pm_init);