Back to home page

OSCL-LXR
 
 

     

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 /*
0003  * kernel/power/main.c - PM subsystem core functionality.
0004  *
0005  * Copyright (c) 2003 Patrick Mochel
0006  * Copyright (c) 2003 Open Source Development Lab
0007  */
0008 
0009 #include <linux/export.h>
0010 #include <linux/kobject.h>
0011 #include <linux/string.h>
0012 #include <linux/pm-trace.h>
0013 #include <linux/workqueue.h>
0014 #include <linux/debugfs.h>
0015 #include <linux/seq_file.h>
0016 #include <linux/suspend.h>
0017 #include <linux/syscalls.h>
0018 #include <linux/pm_runtime.h>
0019 
0020 #include "power.h"
0021 
0022 #ifdef CONFIG_PM_SLEEP
0023 
0024 void lock_system_sleep(void)
0025 {
0026     current->flags |= PF_FREEZER_SKIP;
0027     mutex_lock(&system_transition_mutex);
0028 }
0029 EXPORT_SYMBOL_GPL(lock_system_sleep);
0030 
0031 void unlock_system_sleep(void)
0032 {
0033     /*
0034      * Don't use freezer_count() because we don't want the call to
0035      * try_to_freeze() here.
0036      *
0037      * Reason:
0038      * Fundamentally, we just don't need it, because freezing condition
0039      * doesn't come into effect until we release the
0040      * system_transition_mutex lock, since the freezer always works with
0041      * system_transition_mutex held.
0042      *
0043      * More importantly, in the case of hibernation,
0044      * unlock_system_sleep() gets called in snapshot_read() and
0045      * snapshot_write() when the freezing condition is still in effect.
0046      * Which means, if we use try_to_freeze() here, it would make them
0047      * enter the refrigerator, thus causing hibernation to lockup.
0048      */
0049     current->flags &= ~PF_FREEZER_SKIP;
0050     mutex_unlock(&system_transition_mutex);
0051 }
0052 EXPORT_SYMBOL_GPL(unlock_system_sleep);
0053 
0054 void ksys_sync_helper(void)
0055 {
0056     ktime_t start;
0057     long elapsed_msecs;
0058 
0059     start = ktime_get();
0060     ksys_sync();
0061     elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
0062     pr_info("Filesystems sync: %ld.%03ld seconds\n",
0063         elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
0064 }
0065 EXPORT_SYMBOL_GPL(ksys_sync_helper);
0066 
0067 /* Routines for PM-transition notifications */
0068 
0069 static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
0070 
0071 int register_pm_notifier(struct notifier_block *nb)
0072 {
0073     return blocking_notifier_chain_register(&pm_chain_head, nb);
0074 }
0075 EXPORT_SYMBOL_GPL(register_pm_notifier);
0076 
0077 int unregister_pm_notifier(struct notifier_block *nb)
0078 {
0079     return blocking_notifier_chain_unregister(&pm_chain_head, nb);
0080 }
0081 EXPORT_SYMBOL_GPL(unregister_pm_notifier);
0082 
0083 int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down)
0084 {
0085     int ret;
0086 
0087     ret = blocking_notifier_call_chain_robust(&pm_chain_head, val_up, val_down, NULL);
0088 
0089     return notifier_to_errno(ret);
0090 }
0091 
0092 int pm_notifier_call_chain(unsigned long val)
0093 {
0094     return blocking_notifier_call_chain(&pm_chain_head, val, NULL);
0095 }
0096 
0097 /* If set, devices may be suspended and resumed asynchronously. */
0098 int pm_async_enabled = 1;
0099 
0100 static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
0101                  char *buf)
0102 {
0103     return sprintf(buf, "%d\n", pm_async_enabled);
0104 }
0105 
0106 static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
0107                   const char *buf, size_t n)
0108 {
0109     unsigned long val;
0110 
0111     if (kstrtoul(buf, 10, &val))
0112         return -EINVAL;
0113 
0114     if (val > 1)
0115         return -EINVAL;
0116 
0117     pm_async_enabled = val;
0118     return n;
0119 }
0120 
0121 power_attr(pm_async);
0122 
0123 #ifdef CONFIG_SUSPEND
0124 static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
0125                   char *buf)
0126 {
0127     char *s = buf;
0128     suspend_state_t i;
0129 
0130     for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) {
0131         if (i >= PM_SUSPEND_MEM && cxl_mem_active())
0132             continue;
0133         if (mem_sleep_states[i]) {
0134             const char *label = mem_sleep_states[i];
0135 
0136             if (mem_sleep_current == i)
0137                 s += sprintf(s, "[%s] ", label);
0138             else
0139                 s += sprintf(s, "%s ", label);
0140         }
0141     }
0142 
0143     /* Convert the last space to a newline if needed. */
0144     if (s != buf)
0145         *(s-1) = '\n';
0146 
0147     return (s - buf);
0148 }
0149 
0150 static suspend_state_t decode_suspend_state(const char *buf, size_t n)
0151 {
0152     suspend_state_t state;
0153     char *p;
0154     int len;
0155 
0156     p = memchr(buf, '\n', n);
0157     len = p ? p - buf : n;
0158 
0159     for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
0160         const char *label = mem_sleep_states[state];
0161 
0162         if (label && len == strlen(label) && !strncmp(buf, label, len))
0163             return state;
0164     }
0165 
0166     return PM_SUSPEND_ON;
0167 }
0168 
0169 static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
0170                    const char *buf, size_t n)
0171 {
0172     suspend_state_t state;
0173     int error;
0174 
0175     error = pm_autosleep_lock();
0176     if (error)
0177         return error;
0178 
0179     if (pm_autosleep_state() > PM_SUSPEND_ON) {
0180         error = -EBUSY;
0181         goto out;
0182     }
0183 
0184     state = decode_suspend_state(buf, n);
0185     if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
0186         mem_sleep_current = state;
0187     else
0188         error = -EINVAL;
0189 
0190  out:
0191     pm_autosleep_unlock();
0192     return error ? error : n;
0193 }
0194 
0195 power_attr(mem_sleep);
0196 
0197 /*
0198  * sync_on_suspend: invoke ksys_sync_helper() before suspend.
0199  *
0200  * show() returns whether ksys_sync_helper() is invoked before suspend.
0201  * store() accepts 0 or 1.  0 disables ksys_sync_helper() and 1 enables it.
0202  */
0203 bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC);
0204 
0205 static ssize_t sync_on_suspend_show(struct kobject *kobj,
0206                    struct kobj_attribute *attr, char *buf)
0207 {
0208     return sprintf(buf, "%d\n", sync_on_suspend_enabled);
0209 }
0210 
0211 static ssize_t sync_on_suspend_store(struct kobject *kobj,
0212                     struct kobj_attribute *attr,
0213                     const char *buf, size_t n)
0214 {
0215     unsigned long val;
0216 
0217     if (kstrtoul(buf, 10, &val))
0218         return -EINVAL;
0219 
0220     if (val > 1)
0221         return -EINVAL;
0222 
0223     sync_on_suspend_enabled = !!val;
0224     return n;
0225 }
0226 
0227 power_attr(sync_on_suspend);
0228 #endif /* CONFIG_SUSPEND */
0229 
0230 #ifdef CONFIG_PM_SLEEP_DEBUG
0231 int pm_test_level = TEST_NONE;
0232 
0233 static const char * const pm_tests[__TEST_AFTER_LAST] = {
0234     [TEST_NONE] = "none",
0235     [TEST_CORE] = "core",
0236     [TEST_CPUS] = "processors",
0237     [TEST_PLATFORM] = "platform",
0238     [TEST_DEVICES] = "devices",
0239     [TEST_FREEZER] = "freezer",
0240 };
0241 
0242 static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
0243                 char *buf)
0244 {
0245     char *s = buf;
0246     int level;
0247 
0248     for (level = TEST_FIRST; level <= TEST_MAX; level++)
0249         if (pm_tests[level]) {
0250             if (level == pm_test_level)
0251                 s += sprintf(s, "[%s] ", pm_tests[level]);
0252             else
0253                 s += sprintf(s, "%s ", pm_tests[level]);
0254         }
0255 
0256     if (s != buf)
0257         /* convert the last space to a newline */
0258         *(s-1) = '\n';
0259 
0260     return (s - buf);
0261 }
0262 
0263 static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
0264                 const char *buf, size_t n)
0265 {
0266     const char * const *s;
0267     int level;
0268     char *p;
0269     int len;
0270     int error = -EINVAL;
0271 
0272     p = memchr(buf, '\n', n);
0273     len = p ? p - buf : n;
0274 
0275     lock_system_sleep();
0276 
0277     level = TEST_FIRST;
0278     for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
0279         if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
0280             pm_test_level = level;
0281             error = 0;
0282             break;
0283         }
0284 
0285     unlock_system_sleep();
0286 
0287     return error ? error : n;
0288 }
0289 
0290 power_attr(pm_test);
0291 #endif /* CONFIG_PM_SLEEP_DEBUG */
0292 
0293 static char *suspend_step_name(enum suspend_stat_step step)
0294 {
0295     switch (step) {
0296     case SUSPEND_FREEZE:
0297         return "freeze";
0298     case SUSPEND_PREPARE:
0299         return "prepare";
0300     case SUSPEND_SUSPEND:
0301         return "suspend";
0302     case SUSPEND_SUSPEND_NOIRQ:
0303         return "suspend_noirq";
0304     case SUSPEND_RESUME_NOIRQ:
0305         return "resume_noirq";
0306     case SUSPEND_RESUME:
0307         return "resume";
0308     default:
0309         return "";
0310     }
0311 }
0312 
0313 #define suspend_attr(_name)                 \
0314 static ssize_t _name##_show(struct kobject *kobj,       \
0315         struct kobj_attribute *attr, char *buf)     \
0316 {                               \
0317     return sprintf(buf, "%d\n", suspend_stats._name);   \
0318 }                               \
0319 static struct kobj_attribute _name = __ATTR_RO(_name)
0320 
0321 suspend_attr(success);
0322 suspend_attr(fail);
0323 suspend_attr(failed_freeze);
0324 suspend_attr(failed_prepare);
0325 suspend_attr(failed_suspend);
0326 suspend_attr(failed_suspend_late);
0327 suspend_attr(failed_suspend_noirq);
0328 suspend_attr(failed_resume);
0329 suspend_attr(failed_resume_early);
0330 suspend_attr(failed_resume_noirq);
0331 
0332 static ssize_t last_failed_dev_show(struct kobject *kobj,
0333         struct kobj_attribute *attr, char *buf)
0334 {
0335     int index;
0336     char *last_failed_dev = NULL;
0337 
0338     index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
0339     index %= REC_FAILED_NUM;
0340     last_failed_dev = suspend_stats.failed_devs[index];
0341 
0342     return sprintf(buf, "%s\n", last_failed_dev);
0343 }
0344 static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
0345 
0346 static ssize_t last_failed_errno_show(struct kobject *kobj,
0347         struct kobj_attribute *attr, char *buf)
0348 {
0349     int index;
0350     int last_failed_errno;
0351 
0352     index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
0353     index %= REC_FAILED_NUM;
0354     last_failed_errno = suspend_stats.errno[index];
0355 
0356     return sprintf(buf, "%d\n", last_failed_errno);
0357 }
0358 static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
0359 
0360 static ssize_t last_failed_step_show(struct kobject *kobj,
0361         struct kobj_attribute *attr, char *buf)
0362 {
0363     int index;
0364     enum suspend_stat_step step;
0365     char *last_failed_step = NULL;
0366 
0367     index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
0368     index %= REC_FAILED_NUM;
0369     step = suspend_stats.failed_steps[index];
0370     last_failed_step = suspend_step_name(step);
0371 
0372     return sprintf(buf, "%s\n", last_failed_step);
0373 }
0374 static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
0375 
0376 static struct attribute *suspend_attrs[] = {
0377     &success.attr,
0378     &fail.attr,
0379     &failed_freeze.attr,
0380     &failed_prepare.attr,
0381     &failed_suspend.attr,
0382     &failed_suspend_late.attr,
0383     &failed_suspend_noirq.attr,
0384     &failed_resume.attr,
0385     &failed_resume_early.attr,
0386     &failed_resume_noirq.attr,
0387     &last_failed_dev.attr,
0388     &last_failed_errno.attr,
0389     &last_failed_step.attr,
0390     NULL,
0391 };
0392 
0393 static const struct attribute_group suspend_attr_group = {
0394     .name = "suspend_stats",
0395     .attrs = suspend_attrs,
0396 };
0397 
0398 #ifdef CONFIG_DEBUG_FS
0399 static int suspend_stats_show(struct seq_file *s, void *unused)
0400 {
0401     int i, index, last_dev, last_errno, last_step;
0402 
0403     last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
0404     last_dev %= REC_FAILED_NUM;
0405     last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
0406     last_errno %= REC_FAILED_NUM;
0407     last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
0408     last_step %= REC_FAILED_NUM;
0409     seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
0410             "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
0411             "success", suspend_stats.success,
0412             "fail", suspend_stats.fail,
0413             "failed_freeze", suspend_stats.failed_freeze,
0414             "failed_prepare", suspend_stats.failed_prepare,
0415             "failed_suspend", suspend_stats.failed_suspend,
0416             "failed_suspend_late",
0417                 suspend_stats.failed_suspend_late,
0418             "failed_suspend_noirq",
0419                 suspend_stats.failed_suspend_noirq,
0420             "failed_resume", suspend_stats.failed_resume,
0421             "failed_resume_early",
0422                 suspend_stats.failed_resume_early,
0423             "failed_resume_noirq",
0424                 suspend_stats.failed_resume_noirq);
0425     seq_printf(s,   "failures:\n  last_failed_dev:\t%-s\n",
0426             suspend_stats.failed_devs[last_dev]);
0427     for (i = 1; i < REC_FAILED_NUM; i++) {
0428         index = last_dev + REC_FAILED_NUM - i;
0429         index %= REC_FAILED_NUM;
0430         seq_printf(s, "\t\t\t%-s\n",
0431             suspend_stats.failed_devs[index]);
0432     }
0433     seq_printf(s,   "  last_failed_errno:\t%-d\n",
0434             suspend_stats.errno[last_errno]);
0435     for (i = 1; i < REC_FAILED_NUM; i++) {
0436         index = last_errno + REC_FAILED_NUM - i;
0437         index %= REC_FAILED_NUM;
0438         seq_printf(s, "\t\t\t%-d\n",
0439             suspend_stats.errno[index]);
0440     }
0441     seq_printf(s,   "  last_failed_step:\t%-s\n",
0442             suspend_step_name(
0443                 suspend_stats.failed_steps[last_step]));
0444     for (i = 1; i < REC_FAILED_NUM; i++) {
0445         index = last_step + REC_FAILED_NUM - i;
0446         index %= REC_FAILED_NUM;
0447         seq_printf(s, "\t\t\t%-s\n",
0448             suspend_step_name(
0449                 suspend_stats.failed_steps[index]));
0450     }
0451 
0452     return 0;
0453 }
0454 DEFINE_SHOW_ATTRIBUTE(suspend_stats);
0455 
0456 static int __init pm_debugfs_init(void)
0457 {
0458     debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
0459             NULL, NULL, &suspend_stats_fops);
0460     return 0;
0461 }
0462 
0463 late_initcall(pm_debugfs_init);
0464 #endif /* CONFIG_DEBUG_FS */
0465 
0466 #endif /* CONFIG_PM_SLEEP */
0467 
0468 #ifdef CONFIG_PM_SLEEP_DEBUG
0469 /*
0470  * pm_print_times: print time taken by devices to suspend and resume.
0471  *
0472  * show() returns whether printing of suspend and resume times is enabled.
0473  * store() accepts 0 or 1.  0 disables printing and 1 enables it.
0474  */
0475 bool pm_print_times_enabled;
0476 
0477 static ssize_t pm_print_times_show(struct kobject *kobj,
0478                    struct kobj_attribute *attr, char *buf)
0479 {
0480     return sprintf(buf, "%d\n", pm_print_times_enabled);
0481 }
0482 
0483 static ssize_t pm_print_times_store(struct kobject *kobj,
0484                     struct kobj_attribute *attr,
0485                     const char *buf, size_t n)
0486 {
0487     unsigned long val;
0488 
0489     if (kstrtoul(buf, 10, &val))
0490         return -EINVAL;
0491 
0492     if (val > 1)
0493         return -EINVAL;
0494 
0495     pm_print_times_enabled = !!val;
0496     return n;
0497 }
0498 
0499 power_attr(pm_print_times);
0500 
0501 static inline void pm_print_times_init(void)
0502 {
0503     pm_print_times_enabled = !!initcall_debug;
0504 }
0505 
0506 static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
0507                     struct kobj_attribute *attr,
0508                     char *buf)
0509 {
0510     if (!pm_wakeup_irq())
0511         return -ENODATA;
0512 
0513     return sprintf(buf, "%u\n", pm_wakeup_irq());
0514 }
0515 
0516 power_attr_ro(pm_wakeup_irq);
0517 
0518 bool pm_debug_messages_on __read_mostly;
0519 
0520 static ssize_t pm_debug_messages_show(struct kobject *kobj,
0521                       struct kobj_attribute *attr, char *buf)
0522 {
0523     return sprintf(buf, "%d\n", pm_debug_messages_on);
0524 }
0525 
0526 static ssize_t pm_debug_messages_store(struct kobject *kobj,
0527                        struct kobj_attribute *attr,
0528                        const char *buf, size_t n)
0529 {
0530     unsigned long val;
0531 
0532     if (kstrtoul(buf, 10, &val))
0533         return -EINVAL;
0534 
0535     if (val > 1)
0536         return -EINVAL;
0537 
0538     pm_debug_messages_on = !!val;
0539     return n;
0540 }
0541 
0542 power_attr(pm_debug_messages);
0543 
0544 static int __init pm_debug_messages_setup(char *str)
0545 {
0546     pm_debug_messages_on = true;
0547     return 1;
0548 }
0549 __setup("pm_debug_messages", pm_debug_messages_setup);
0550 
0551 #else /* !CONFIG_PM_SLEEP_DEBUG */
0552 static inline void pm_print_times_init(void) {}
0553 #endif /* CONFIG_PM_SLEEP_DEBUG */
0554 
0555 struct kobject *power_kobj;
0556 
0557 /*
0558  * state - control system sleep states.
0559  *
0560  * show() returns available sleep state labels, which may be "mem", "standby",
0561  * "freeze" and "disk" (hibernation).
0562  * See Documentation/admin-guide/pm/sleep-states.rst for a description of
0563  * what they mean.
0564  *
0565  * store() accepts one of those strings, translates it into the proper
0566  * enumerated value, and initiates a suspend transition.
0567  */
0568 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
0569               char *buf)
0570 {
0571     char *s = buf;
0572 #ifdef CONFIG_SUSPEND
0573     suspend_state_t i;
0574 
0575     for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
0576         if (pm_states[i])
0577             s += sprintf(s,"%s ", pm_states[i]);
0578 
0579 #endif
0580     if (hibernation_available())
0581         s += sprintf(s, "disk ");
0582     if (s != buf)
0583         /* convert the last space to a newline */
0584         *(s-1) = '\n';
0585     return (s - buf);
0586 }
0587 
0588 static suspend_state_t decode_state(const char *buf, size_t n)
0589 {
0590 #ifdef CONFIG_SUSPEND
0591     suspend_state_t state;
0592 #endif
0593     char *p;
0594     int len;
0595 
0596     p = memchr(buf, '\n', n);
0597     len = p ? p - buf : n;
0598 
0599     /* Check hibernation first. */
0600     if (len == 4 && str_has_prefix(buf, "disk"))
0601         return PM_SUSPEND_MAX;
0602 
0603 #ifdef CONFIG_SUSPEND
0604     for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
0605         const char *label = pm_states[state];
0606 
0607         if (label && len == strlen(label) && !strncmp(buf, label, len))
0608             return state;
0609     }
0610 #endif
0611 
0612     return PM_SUSPEND_ON;
0613 }
0614 
0615 static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
0616                const char *buf, size_t n)
0617 {
0618     suspend_state_t state;
0619     int error;
0620 
0621     error = pm_autosleep_lock();
0622     if (error)
0623         return error;
0624 
0625     if (pm_autosleep_state() > PM_SUSPEND_ON) {
0626         error = -EBUSY;
0627         goto out;
0628     }
0629 
0630     state = decode_state(buf, n);
0631     if (state < PM_SUSPEND_MAX) {
0632         if (state == PM_SUSPEND_MEM)
0633             state = mem_sleep_current;
0634 
0635         error = pm_suspend(state);
0636     } else if (state == PM_SUSPEND_MAX) {
0637         error = hibernate();
0638     } else {
0639         error = -EINVAL;
0640     }
0641 
0642  out:
0643     pm_autosleep_unlock();
0644     return error ? error : n;
0645 }
0646 
0647 power_attr(state);
0648 
0649 #ifdef CONFIG_PM_SLEEP
0650 /*
0651  * The 'wakeup_count' attribute, along with the functions defined in
0652  * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
0653  * handled in a non-racy way.
0654  *
0655  * If a wakeup event occurs when the system is in a sleep state, it simply is
0656  * woken up.  In turn, if an event that would wake the system up from a sleep
0657  * state occurs when it is undergoing a transition to that sleep state, the
0658  * transition should be aborted.  Moreover, if such an event occurs when the
0659  * system is in the working state, an attempt to start a transition to the
0660  * given sleep state should fail during certain period after the detection of
0661  * the event.  Using the 'state' attribute alone is not sufficient to satisfy
0662  * these requirements, because a wakeup event may occur exactly when 'state'
0663  * is being written to and may be delivered to user space right before it is
0664  * frozen, so the event will remain only partially processed until the system is
0665  * woken up by another event.  In particular, it won't cause the transition to
0666  * a sleep state to be aborted.
0667  *
0668  * This difficulty may be overcome if user space uses 'wakeup_count' before
0669  * writing to 'state'.  It first should read from 'wakeup_count' and store
0670  * the read value.  Then, after carrying out its own preparations for the system
0671  * transition to a sleep state, it should write the stored value to
0672  * 'wakeup_count'.  If that fails, at least one wakeup event has occurred since
0673  * 'wakeup_count' was read and 'state' should not be written to.  Otherwise, it
0674  * is allowed to write to 'state', but the transition will be aborted if there
0675  * are any wakeup events detected after 'wakeup_count' was written to.
0676  */
0677 
0678 static ssize_t wakeup_count_show(struct kobject *kobj,
0679                 struct kobj_attribute *attr,
0680                 char *buf)
0681 {
0682     unsigned int val;
0683 
0684     return pm_get_wakeup_count(&val, true) ?
0685         sprintf(buf, "%u\n", val) : -EINTR;
0686 }
0687 
0688 static ssize_t wakeup_count_store(struct kobject *kobj,
0689                 struct kobj_attribute *attr,
0690                 const char *buf, size_t n)
0691 {
0692     unsigned int val;
0693     int error;
0694 
0695     error = pm_autosleep_lock();
0696     if (error)
0697         return error;
0698 
0699     if (pm_autosleep_state() > PM_SUSPEND_ON) {
0700         error = -EBUSY;
0701         goto out;
0702     }
0703 
0704     error = -EINVAL;
0705     if (sscanf(buf, "%u", &val) == 1) {
0706         if (pm_save_wakeup_count(val))
0707             error = n;
0708         else
0709             pm_print_active_wakeup_sources();
0710     }
0711 
0712  out:
0713     pm_autosleep_unlock();
0714     return error;
0715 }
0716 
0717 power_attr(wakeup_count);
0718 
0719 #ifdef CONFIG_PM_AUTOSLEEP
0720 static ssize_t autosleep_show(struct kobject *kobj,
0721                   struct kobj_attribute *attr,
0722                   char *buf)
0723 {
0724     suspend_state_t state = pm_autosleep_state();
0725 
0726     if (state == PM_SUSPEND_ON)
0727         return sprintf(buf, "off\n");
0728 
0729 #ifdef CONFIG_SUSPEND
0730     if (state < PM_SUSPEND_MAX)
0731         return sprintf(buf, "%s\n", pm_states[state] ?
0732                     pm_states[state] : "error");
0733 #endif
0734 #ifdef CONFIG_HIBERNATION
0735     return sprintf(buf, "disk\n");
0736 #else
0737     return sprintf(buf, "error");
0738 #endif
0739 }
0740 
0741 static ssize_t autosleep_store(struct kobject *kobj,
0742                    struct kobj_attribute *attr,
0743                    const char *buf, size_t n)
0744 {
0745     suspend_state_t state = decode_state(buf, n);
0746     int error;
0747 
0748     if (state == PM_SUSPEND_ON
0749         && strcmp(buf, "off") && strcmp(buf, "off\n"))
0750         return -EINVAL;
0751 
0752     if (state == PM_SUSPEND_MEM)
0753         state = mem_sleep_current;
0754 
0755     error = pm_autosleep_set_state(state);
0756     return error ? error : n;
0757 }
0758 
0759 power_attr(autosleep);
0760 #endif /* CONFIG_PM_AUTOSLEEP */
0761 
0762 #ifdef CONFIG_PM_WAKELOCKS
0763 static ssize_t wake_lock_show(struct kobject *kobj,
0764                   struct kobj_attribute *attr,
0765                   char *buf)
0766 {
0767     return pm_show_wakelocks(buf, true);
0768 }
0769 
0770 static ssize_t wake_lock_store(struct kobject *kobj,
0771                    struct kobj_attribute *attr,
0772                    const char *buf, size_t n)
0773 {
0774     int error = pm_wake_lock(buf);
0775     return error ? error : n;
0776 }
0777 
0778 power_attr(wake_lock);
0779 
0780 static ssize_t wake_unlock_show(struct kobject *kobj,
0781                 struct kobj_attribute *attr,
0782                 char *buf)
0783 {
0784     return pm_show_wakelocks(buf, false);
0785 }
0786 
0787 static ssize_t wake_unlock_store(struct kobject *kobj,
0788                  struct kobj_attribute *attr,
0789                  const char *buf, size_t n)
0790 {
0791     int error = pm_wake_unlock(buf);
0792     return error ? error : n;
0793 }
0794 
0795 power_attr(wake_unlock);
0796 
0797 #endif /* CONFIG_PM_WAKELOCKS */
0798 #endif /* CONFIG_PM_SLEEP */
0799 
0800 #ifdef CONFIG_PM_TRACE
0801 int pm_trace_enabled;
0802 
0803 static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
0804                  char *buf)
0805 {
0806     return sprintf(buf, "%d\n", pm_trace_enabled);
0807 }
0808 
0809 static ssize_t
0810 pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
0811            const char *buf, size_t n)
0812 {
0813     int val;
0814 
0815     if (sscanf(buf, "%d", &val) == 1) {
0816         pm_trace_enabled = !!val;
0817         if (pm_trace_enabled) {
0818             pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
0819                 "PM: Correct system time has to be restored manually after resume.\n");
0820         }
0821         return n;
0822     }
0823     return -EINVAL;
0824 }
0825 
0826 power_attr(pm_trace);
0827 
0828 static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
0829                        struct kobj_attribute *attr,
0830                        char *buf)
0831 {
0832     return show_trace_dev_match(buf, PAGE_SIZE);
0833 }
0834 
0835 power_attr_ro(pm_trace_dev_match);
0836 
0837 #endif /* CONFIG_PM_TRACE */
0838 
0839 #ifdef CONFIG_FREEZER
0840 static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
0841                       struct kobj_attribute *attr, char *buf)
0842 {
0843     return sprintf(buf, "%u\n", freeze_timeout_msecs);
0844 }
0845 
0846 static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
0847                        struct kobj_attribute *attr,
0848                        const char *buf, size_t n)
0849 {
0850     unsigned long val;
0851 
0852     if (kstrtoul(buf, 10, &val))
0853         return -EINVAL;
0854 
0855     freeze_timeout_msecs = val;
0856     return n;
0857 }
0858 
0859 power_attr(pm_freeze_timeout);
0860 
0861 #endif  /* CONFIG_FREEZER*/
0862 
0863 static struct attribute * g[] = {
0864     &state_attr.attr,
0865 #ifdef CONFIG_PM_TRACE
0866     &pm_trace_attr.attr,
0867     &pm_trace_dev_match_attr.attr,
0868 #endif
0869 #ifdef CONFIG_PM_SLEEP
0870     &pm_async_attr.attr,
0871     &wakeup_count_attr.attr,
0872 #ifdef CONFIG_SUSPEND
0873     &mem_sleep_attr.attr,
0874     &sync_on_suspend_attr.attr,
0875 #endif
0876 #ifdef CONFIG_PM_AUTOSLEEP
0877     &autosleep_attr.attr,
0878 #endif
0879 #ifdef CONFIG_PM_WAKELOCKS
0880     &wake_lock_attr.attr,
0881     &wake_unlock_attr.attr,
0882 #endif
0883 #ifdef CONFIG_PM_SLEEP_DEBUG
0884     &pm_test_attr.attr,
0885     &pm_print_times_attr.attr,
0886     &pm_wakeup_irq_attr.attr,
0887     &pm_debug_messages_attr.attr,
0888 #endif
0889 #endif
0890 #ifdef CONFIG_FREEZER
0891     &pm_freeze_timeout_attr.attr,
0892 #endif
0893     NULL,
0894 };
0895 
0896 static const struct attribute_group attr_group = {
0897     .attrs = g,
0898 };
0899 
0900 static const struct attribute_group *attr_groups[] = {
0901     &attr_group,
0902 #ifdef CONFIG_PM_SLEEP
0903     &suspend_attr_group,
0904 #endif
0905     NULL,
0906 };
0907 
0908 struct workqueue_struct *pm_wq;
0909 EXPORT_SYMBOL_GPL(pm_wq);
0910 
0911 static int __init pm_start_workqueue(void)
0912 {
0913     pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
0914 
0915     return pm_wq ? 0 : -ENOMEM;
0916 }
0917 
0918 static int __init pm_init(void)
0919 {
0920     int error = pm_start_workqueue();
0921     if (error)
0922         return error;
0923     hibernate_image_size_init();
0924     hibernate_reserved_size_init();
0925     pm_states_init();
0926     power_kobj = kobject_create_and_add("power", NULL);
0927     if (!power_kobj)
0928         return -ENOMEM;
0929     error = sysfs_create_groups(power_kobj, attr_groups);
0930     if (error)
0931         return error;
0932     pm_print_times_init();
0933     return pm_autosleep_init();
0934 }
0935 
0936 core_initcall(pm_init);
[ Source navigation ] [ Diff markup ] [ Identifier search ] [ general search ]

This page was automatically generated by the 2.1.0 LXR engine.

The LXR team
Valid CSS 2.1! Valid HTML 4.01!