1 /* 2 * kernel/power/main.c - PM subsystem core functionality. 3 * 4 * Copyright (c) 2003 Patrick Mochel 5 * Copyright (c) 2003 Open Source Development Lab 6 * 7 * This file is released under the GPLv2 8 * 9 */ 10 11 #include <linux/export.h> 12 #include <linux/kobject.h> 13 #include <linux/string.h> 14 #include <linux/pm-trace.h> 15 #include <linux/workqueue.h> 16 #include <linux/debugfs.h> 17 #include <linux/seq_file.h> 18 19 #include "power.h" 20 21 DEFINE_MUTEX(pm_mutex); 22 23 #ifdef CONFIG_PM_SLEEP 24 25 void lock_system_sleep(void) 26 { 27 current->flags |= PF_FREEZER_SKIP; 28 mutex_lock(&pm_mutex); 29 } 30 EXPORT_SYMBOL_GPL(lock_system_sleep); 31 32 void unlock_system_sleep(void) 33 { 34 /* 35 * Don't use freezer_count() because we don't want the call to 36 * try_to_freeze() here. 37 * 38 * Reason: 39 * Fundamentally, we just don't need it, because freezing condition 40 * doesn't come into effect until we release the pm_mutex lock, 41 * since the freezer always works with pm_mutex held. 42 * 43 * More importantly, in the case of hibernation, 44 * unlock_system_sleep() gets called in snapshot_read() and 45 * snapshot_write() when the freezing condition is still in effect. 46 * Which means, if we use try_to_freeze() here, it would make them 47 * enter the refrigerator, thus causing hibernation to lockup. 48 */ 49 current->flags &= ~PF_FREEZER_SKIP; 50 mutex_unlock(&pm_mutex); 51 } 52 EXPORT_SYMBOL_GPL(unlock_system_sleep); 53 54 /* Routines for PM-transition notifications */ 55 56 static BLOCKING_NOTIFIER_HEAD(pm_chain_head); 57 58 int register_pm_notifier(struct notifier_block *nb) 59 { 60 return blocking_notifier_chain_register(&pm_chain_head, nb); 61 } 62 EXPORT_SYMBOL_GPL(register_pm_notifier); 63 64 int unregister_pm_notifier(struct notifier_block *nb) 65 { 66 return blocking_notifier_chain_unregister(&pm_chain_head, nb); 67 } 68 EXPORT_SYMBOL_GPL(unregister_pm_notifier); 69 70 int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls) 71 { 72 int ret; 73 74 ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL, 75 nr_to_call, nr_calls); 76 77 return notifier_to_errno(ret); 78 } 79 int pm_notifier_call_chain(unsigned long val) 80 { 81 return __pm_notifier_call_chain(val, -1, NULL); 82 } 83 84 /* If set, devices may be suspended and resumed asynchronously. */ 85 int pm_async_enabled = 1; 86 87 static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr, 88 char *buf) 89 { 90 return sprintf(buf, "%d\n", pm_async_enabled); 91 } 92 93 static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr, 94 const char *buf, size_t n) 95 { 96 unsigned long val; 97 98 if (kstrtoul(buf, 10, &val)) 99 return -EINVAL; 100 101 if (val > 1) 102 return -EINVAL; 103 104 pm_async_enabled = val; 105 return n; 106 } 107 108 power_attr(pm_async); 109 110 #ifdef CONFIG_SUSPEND 111 static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr, 112 char *buf) 113 { 114 char *s = buf; 115 suspend_state_t i; 116 117 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) 118 if (mem_sleep_states[i]) { 119 const char *label = mem_sleep_states[i]; 120 121 if (mem_sleep_current == i) 122 s += sprintf(s, "[%s] ", label); 123 else 124 s += sprintf(s, "%s ", label); 125 } 126 127 /* Convert the last space to a newline if needed. */ 128 if (s != buf) 129 *(s-1) = '\n'; 130 131 return (s - buf); 132 } 133 134 static suspend_state_t decode_suspend_state(const char *buf, size_t n) 135 { 136 suspend_state_t state; 137 char *p; 138 int len; 139 140 p = memchr(buf, '\n', n); 141 len = p ? p - buf : n; 142 143 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) { 144 const char *label = mem_sleep_states[state]; 145 146 if (label && len == strlen(label) && !strncmp(buf, label, len)) 147 return state; 148 } 149 150 return PM_SUSPEND_ON; 151 } 152 153 static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr, 154 const char *buf, size_t n) 155 { 156 suspend_state_t state; 157 int error; 158 159 error = pm_autosleep_lock(); 160 if (error) 161 return error; 162 163 if (pm_autosleep_state() > PM_SUSPEND_ON) { 164 error = -EBUSY; 165 goto out; 166 } 167 168 state = decode_suspend_state(buf, n); 169 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON) 170 mem_sleep_current = state; 171 else 172 error = -EINVAL; 173 174 out: 175 pm_autosleep_unlock(); 176 return error ? error : n; 177 } 178 179 power_attr(mem_sleep); 180 #endif /* CONFIG_SUSPEND */ 181 182 #ifdef CONFIG_PM_SLEEP_DEBUG 183 int pm_test_level = TEST_NONE; 184 185 static const char * const pm_tests[__TEST_AFTER_LAST] = { 186 [TEST_NONE] = "none", 187 [TEST_CORE] = "core", 188 [TEST_CPUS] = "processors", 189 [TEST_PLATFORM] = "platform", 190 [TEST_DEVICES] = "devices", 191 [TEST_FREEZER] = "freezer", 192 }; 193 194 static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr, 195 char *buf) 196 { 197 char *s = buf; 198 int level; 199 200 for (level = TEST_FIRST; level <= TEST_MAX; level++) 201 if (pm_tests[level]) { 202 if (level == pm_test_level) 203 s += sprintf(s, "[%s] ", pm_tests[level]); 204 else 205 s += sprintf(s, "%s ", pm_tests[level]); 206 } 207 208 if (s != buf) 209 /* convert the last space to a newline */ 210 *(s-1) = '\n'; 211 212 return (s - buf); 213 } 214 215 static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, 216 const char *buf, size_t n) 217 { 218 const char * const *s; 219 int level; 220 char *p; 221 int len; 222 int error = -EINVAL; 223 224 p = memchr(buf, '\n', n); 225 len = p ? p - buf : n; 226 227 lock_system_sleep(); 228 229 level = TEST_FIRST; 230 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) 231 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) { 232 pm_test_level = level; 233 error = 0; 234 break; 235 } 236 237 unlock_system_sleep(); 238 239 return error ? error : n; 240 } 241 242 power_attr(pm_test); 243 #endif /* CONFIG_PM_SLEEP_DEBUG */ 244 245 #ifdef CONFIG_DEBUG_FS 246 static char *suspend_step_name(enum suspend_stat_step step) 247 { 248 switch (step) { 249 case SUSPEND_FREEZE: 250 return "freeze"; 251 case SUSPEND_PREPARE: 252 return "prepare"; 253 case SUSPEND_SUSPEND: 254 return "suspend"; 255 case SUSPEND_SUSPEND_NOIRQ: 256 return "suspend_noirq"; 257 case SUSPEND_RESUME_NOIRQ: 258 return "resume_noirq"; 259 case SUSPEND_RESUME: 260 return "resume"; 261 default: 262 return ""; 263 } 264 } 265 266 static int suspend_stats_show(struct seq_file *s, void *unused) 267 { 268 int i, index, last_dev, last_errno, last_step; 269 270 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1; 271 last_dev %= REC_FAILED_NUM; 272 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1; 273 last_errno %= REC_FAILED_NUM; 274 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1; 275 last_step %= REC_FAILED_NUM; 276 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n" 277 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n", 278 "success", suspend_stats.success, 279 "fail", suspend_stats.fail, 280 "failed_freeze", suspend_stats.failed_freeze, 281 "failed_prepare", suspend_stats.failed_prepare, 282 "failed_suspend", suspend_stats.failed_suspend, 283 "failed_suspend_late", 284 suspend_stats.failed_suspend_late, 285 "failed_suspend_noirq", 286 suspend_stats.failed_suspend_noirq, 287 "failed_resume", suspend_stats.failed_resume, 288 "failed_resume_early", 289 suspend_stats.failed_resume_early, 290 "failed_resume_noirq", 291 suspend_stats.failed_resume_noirq); 292 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n", 293 suspend_stats.failed_devs[last_dev]); 294 for (i = 1; i < REC_FAILED_NUM; i++) { 295 index = last_dev + REC_FAILED_NUM - i; 296 index %= REC_FAILED_NUM; 297 seq_printf(s, "\t\t\t%-s\n", 298 suspend_stats.failed_devs[index]); 299 } 300 seq_printf(s, " last_failed_errno:\t%-d\n", 301 suspend_stats.errno[last_errno]); 302 for (i = 1; i < REC_FAILED_NUM; i++) { 303 index = last_errno + REC_FAILED_NUM - i; 304 index %= REC_FAILED_NUM; 305 seq_printf(s, "\t\t\t%-d\n", 306 suspend_stats.errno[index]); 307 } 308 seq_printf(s, " last_failed_step:\t%-s\n", 309 suspend_step_name( 310 suspend_stats.failed_steps[last_step])); 311 for (i = 1; i < REC_FAILED_NUM; i++) { 312 index = last_step + REC_FAILED_NUM - i; 313 index %= REC_FAILED_NUM; 314 seq_printf(s, "\t\t\t%-s\n", 315 suspend_step_name( 316 suspend_stats.failed_steps[index])); 317 } 318 319 return 0; 320 } 321 322 static int suspend_stats_open(struct inode *inode, struct file *file) 323 { 324 return single_open(file, suspend_stats_show, NULL); 325 } 326 327 static const struct file_operations suspend_stats_operations = { 328 .open = suspend_stats_open, 329 .read = seq_read, 330 .llseek = seq_lseek, 331 .release = single_release, 332 }; 333 334 static int __init pm_debugfs_init(void) 335 { 336 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO, 337 NULL, NULL, &suspend_stats_operations); 338 return 0; 339 } 340 341 late_initcall(pm_debugfs_init); 342 #endif /* CONFIG_DEBUG_FS */ 343 344 #endif /* CONFIG_PM_SLEEP */ 345 346 #ifdef CONFIG_PM_SLEEP_DEBUG 347 /* 348 * pm_print_times: print time taken by devices to suspend and resume. 349 * 350 * show() returns whether printing of suspend and resume times is enabled. 351 * store() accepts 0 or 1. 0 disables printing and 1 enables it. 352 */ 353 bool pm_print_times_enabled; 354 355 static ssize_t pm_print_times_show(struct kobject *kobj, 356 struct kobj_attribute *attr, char *buf) 357 { 358 return sprintf(buf, "%d\n", pm_print_times_enabled); 359 } 360 361 static ssize_t pm_print_times_store(struct kobject *kobj, 362 struct kobj_attribute *attr, 363 const char *buf, size_t n) 364 { 365 unsigned long val; 366 367 if (kstrtoul(buf, 10, &val)) 368 return -EINVAL; 369 370 if (val > 1) 371 return -EINVAL; 372 373 pm_print_times_enabled = !!val; 374 return n; 375 } 376 377 power_attr(pm_print_times); 378 379 static inline void pm_print_times_init(void) 380 { 381 pm_print_times_enabled = !!initcall_debug; 382 } 383 384 static ssize_t pm_wakeup_irq_show(struct kobject *kobj, 385 struct kobj_attribute *attr, 386 char *buf) 387 { 388 return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA; 389 } 390 391 power_attr_ro(pm_wakeup_irq); 392 393 bool pm_debug_messages_on __read_mostly; 394 395 static ssize_t pm_debug_messages_show(struct kobject *kobj, 396 struct kobj_attribute *attr, char *buf) 397 { 398 return sprintf(buf, "%d\n", pm_debug_messages_on); 399 } 400 401 static ssize_t pm_debug_messages_store(struct kobject *kobj, 402 struct kobj_attribute *attr, 403 const char *buf, size_t n) 404 { 405 unsigned long val; 406 407 if (kstrtoul(buf, 10, &val)) 408 return -EINVAL; 409 410 if (val > 1) 411 return -EINVAL; 412 413 pm_debug_messages_on = !!val; 414 return n; 415 } 416 417 power_attr(pm_debug_messages); 418 419 /** 420 * __pm_pr_dbg - Print a suspend debug message to the kernel log. 421 * @defer: Whether or not to use printk_deferred() to print the message. 422 * @fmt: Message format. 423 * 424 * The message will be emitted if enabled through the pm_debug_messages 425 * sysfs attribute. 426 */ 427 void __pm_pr_dbg(bool defer, const char *fmt, ...) 428 { 429 struct va_format vaf; 430 va_list args; 431 432 if (!pm_debug_messages_on) 433 return; 434 435 va_start(args, fmt); 436 437 vaf.fmt = fmt; 438 vaf.va = &args; 439 440 if (defer) 441 printk_deferred(KERN_DEBUG "PM: %pV", &vaf); 442 else 443 printk(KERN_DEBUG "PM: %pV", &vaf); 444 445 va_end(args); 446 } 447 448 #else /* !CONFIG_PM_SLEEP_DEBUG */ 449 static inline void pm_print_times_init(void) {} 450 #endif /* CONFIG_PM_SLEEP_DEBUG */ 451 452 struct kobject *power_kobj; 453 454 /** 455 * state - control system sleep states. 456 * 457 * show() returns available sleep state labels, which may be "mem", "standby", 458 * "freeze" and "disk" (hibernation). 459 * See Documentation/admin-guide/pm/sleep-states.rst for a description of 460 * what they mean. 461 * 462 * store() accepts one of those strings, translates it into the proper 463 * enumerated value, and initiates a suspend transition. 464 */ 465 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, 466 char *buf) 467 { 468 char *s = buf; 469 #ifdef CONFIG_SUSPEND 470 suspend_state_t i; 471 472 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) 473 if (pm_states[i]) 474 s += sprintf(s,"%s ", pm_states[i]); 475 476 #endif 477 if (hibernation_available()) 478 s += sprintf(s, "disk "); 479 if (s != buf) 480 /* convert the last space to a newline */ 481 *(s-1) = '\n'; 482 return (s - buf); 483 } 484 485 static suspend_state_t decode_state(const char *buf, size_t n) 486 { 487 #ifdef CONFIG_SUSPEND 488 suspend_state_t state; 489 #endif 490 char *p; 491 int len; 492 493 p = memchr(buf, '\n', n); 494 len = p ? p - buf : n; 495 496 /* Check hibernation first. */ 497 if (len == 4 && !strncmp(buf, "disk", len)) 498 return PM_SUSPEND_MAX; 499 500 #ifdef CONFIG_SUSPEND 501 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) { 502 const char *label = pm_states[state]; 503 504 if (label && len == strlen(label) && !strncmp(buf, label, len)) 505 return state; 506 } 507 #endif 508 509 return PM_SUSPEND_ON; 510 } 511 512 static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, 513 const char *buf, size_t n) 514 { 515 suspend_state_t state; 516 int error; 517 518 error = pm_autosleep_lock(); 519 if (error) 520 return error; 521 522 if (pm_autosleep_state() > PM_SUSPEND_ON) { 523 error = -EBUSY; 524 goto out; 525 } 526 527 state = decode_state(buf, n); 528 if (state < PM_SUSPEND_MAX) { 529 if (state == PM_SUSPEND_MEM) 530 state = mem_sleep_current; 531 532 error = pm_suspend(state); 533 } else if (state == PM_SUSPEND_MAX) { 534 error = hibernate(); 535 } else { 536 error = -EINVAL; 537 } 538 539 out: 540 pm_autosleep_unlock(); 541 return error ? error : n; 542 } 543 544 power_attr(state); 545 546 #ifdef CONFIG_PM_SLEEP 547 /* 548 * The 'wakeup_count' attribute, along with the functions defined in 549 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be 550 * handled in a non-racy way. 551 * 552 * If a wakeup event occurs when the system is in a sleep state, it simply is 553 * woken up. In turn, if an event that would wake the system up from a sleep 554 * state occurs when it is undergoing a transition to that sleep state, the 555 * transition should be aborted. Moreover, if such an event occurs when the 556 * system is in the working state, an attempt to start a transition to the 557 * given sleep state should fail during certain period after the detection of 558 * the event. Using the 'state' attribute alone is not sufficient to satisfy 559 * these requirements, because a wakeup event may occur exactly when 'state' 560 * is being written to and may be delivered to user space right before it is 561 * frozen, so the event will remain only partially processed until the system is 562 * woken up by another event. In particular, it won't cause the transition to 563 * a sleep state to be aborted. 564 * 565 * This difficulty may be overcome if user space uses 'wakeup_count' before 566 * writing to 'state'. It first should read from 'wakeup_count' and store 567 * the read value. Then, after carrying out its own preparations for the system 568 * transition to a sleep state, it should write the stored value to 569 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since 570 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it 571 * is allowed to write to 'state', but the transition will be aborted if there 572 * are any wakeup events detected after 'wakeup_count' was written to. 573 */ 574 575 static ssize_t wakeup_count_show(struct kobject *kobj, 576 struct kobj_attribute *attr, 577 char *buf) 578 { 579 unsigned int val; 580 581 return pm_get_wakeup_count(&val, true) ? 582 sprintf(buf, "%u\n", val) : -EINTR; 583 } 584 585 static ssize_t wakeup_count_store(struct kobject *kobj, 586 struct kobj_attribute *attr, 587 const char *buf, size_t n) 588 { 589 unsigned int val; 590 int error; 591 592 error = pm_autosleep_lock(); 593 if (error) 594 return error; 595 596 if (pm_autosleep_state() > PM_SUSPEND_ON) { 597 error = -EBUSY; 598 goto out; 599 } 600 601 error = -EINVAL; 602 if (sscanf(buf, "%u", &val) == 1) { 603 if (pm_save_wakeup_count(val)) 604 error = n; 605 else 606 pm_print_active_wakeup_sources(); 607 } 608 609 out: 610 pm_autosleep_unlock(); 611 return error; 612 } 613 614 power_attr(wakeup_count); 615 616 #ifdef CONFIG_PM_AUTOSLEEP 617 static ssize_t autosleep_show(struct kobject *kobj, 618 struct kobj_attribute *attr, 619 char *buf) 620 { 621 suspend_state_t state = pm_autosleep_state(); 622 623 if (state == PM_SUSPEND_ON) 624 return sprintf(buf, "off\n"); 625 626 #ifdef CONFIG_SUSPEND 627 if (state < PM_SUSPEND_MAX) 628 return sprintf(buf, "%s\n", pm_states[state] ? 629 pm_states[state] : "error"); 630 #endif 631 #ifdef CONFIG_HIBERNATION 632 return sprintf(buf, "disk\n"); 633 #else 634 return sprintf(buf, "error"); 635 #endif 636 } 637 638 static ssize_t autosleep_store(struct kobject *kobj, 639 struct kobj_attribute *attr, 640 const char *buf, size_t n) 641 { 642 suspend_state_t state = decode_state(buf, n); 643 int error; 644 645 if (state == PM_SUSPEND_ON 646 && strcmp(buf, "off") && strcmp(buf, "off\n")) 647 return -EINVAL; 648 649 if (state == PM_SUSPEND_MEM) 650 state = mem_sleep_current; 651 652 error = pm_autosleep_set_state(state); 653 return error ? error : n; 654 } 655 656 power_attr(autosleep); 657 #endif /* CONFIG_PM_AUTOSLEEP */ 658 659 #ifdef CONFIG_PM_WAKELOCKS 660 static ssize_t wake_lock_show(struct kobject *kobj, 661 struct kobj_attribute *attr, 662 char *buf) 663 { 664 return pm_show_wakelocks(buf, true); 665 } 666 667 static ssize_t wake_lock_store(struct kobject *kobj, 668 struct kobj_attribute *attr, 669 const char *buf, size_t n) 670 { 671 int error = pm_wake_lock(buf); 672 return error ? error : n; 673 } 674 675 power_attr(wake_lock); 676 677 static ssize_t wake_unlock_show(struct kobject *kobj, 678 struct kobj_attribute *attr, 679 char *buf) 680 { 681 return pm_show_wakelocks(buf, false); 682 } 683 684 static ssize_t wake_unlock_store(struct kobject *kobj, 685 struct kobj_attribute *attr, 686 const char *buf, size_t n) 687 { 688 int error = pm_wake_unlock(buf); 689 return error ? error : n; 690 } 691 692 power_attr(wake_unlock); 693 694 #endif /* CONFIG_PM_WAKELOCKS */ 695 #endif /* CONFIG_PM_SLEEP */ 696 697 #ifdef CONFIG_PM_TRACE 698 int pm_trace_enabled; 699 700 static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr, 701 char *buf) 702 { 703 return sprintf(buf, "%d\n", pm_trace_enabled); 704 } 705 706 static ssize_t 707 pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr, 708 const char *buf, size_t n) 709 { 710 int val; 711 712 if (sscanf(buf, "%d", &val) == 1) { 713 pm_trace_enabled = !!val; 714 if (pm_trace_enabled) { 715 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n" 716 "PM: Correct system time has to be restored manually after resume.\n"); 717 } 718 return n; 719 } 720 return -EINVAL; 721 } 722 723 power_attr(pm_trace); 724 725 static ssize_t pm_trace_dev_match_show(struct kobject *kobj, 726 struct kobj_attribute *attr, 727 char *buf) 728 { 729 return show_trace_dev_match(buf, PAGE_SIZE); 730 } 731 732 power_attr_ro(pm_trace_dev_match); 733 734 #endif /* CONFIG_PM_TRACE */ 735 736 #ifdef CONFIG_FREEZER 737 static ssize_t pm_freeze_timeout_show(struct kobject *kobj, 738 struct kobj_attribute *attr, char *buf) 739 { 740 return sprintf(buf, "%u\n", freeze_timeout_msecs); 741 } 742 743 static ssize_t pm_freeze_timeout_store(struct kobject *kobj, 744 struct kobj_attribute *attr, 745 const char *buf, size_t n) 746 { 747 unsigned long val; 748 749 if (kstrtoul(buf, 10, &val)) 750 return -EINVAL; 751 752 freeze_timeout_msecs = val; 753 return n; 754 } 755 756 power_attr(pm_freeze_timeout); 757 758 #endif /* CONFIG_FREEZER*/ 759 760 static struct attribute * g[] = { 761 &state_attr.attr, 762 #ifdef CONFIG_PM_TRACE 763 &pm_trace_attr.attr, 764 &pm_trace_dev_match_attr.attr, 765 #endif 766 #ifdef CONFIG_PM_SLEEP 767 &pm_async_attr.attr, 768 &wakeup_count_attr.attr, 769 #ifdef CONFIG_SUSPEND 770 &mem_sleep_attr.attr, 771 #endif 772 #ifdef CONFIG_PM_AUTOSLEEP 773 &autosleep_attr.attr, 774 #endif 775 #ifdef CONFIG_PM_WAKELOCKS 776 &wake_lock_attr.attr, 777 &wake_unlock_attr.attr, 778 #endif 779 #ifdef CONFIG_PM_SLEEP_DEBUG 780 &pm_test_attr.attr, 781 &pm_print_times_attr.attr, 782 &pm_wakeup_irq_attr.attr, 783 &pm_debug_messages_attr.attr, 784 #endif 785 #endif 786 #ifdef CONFIG_FREEZER 787 &pm_freeze_timeout_attr.attr, 788 #endif 789 NULL, 790 }; 791 792 static const struct attribute_group attr_group = { 793 .attrs = g, 794 }; 795 796 struct workqueue_struct *pm_wq; 797 EXPORT_SYMBOL_GPL(pm_wq); 798 799 static int __init pm_start_workqueue(void) 800 { 801 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0); 802 803 return pm_wq ? 0 : -ENOMEM; 804 } 805 806 static int __init pm_init(void) 807 { 808 int error = pm_start_workqueue(); 809 if (error) 810 return error; 811 hibernate_image_size_init(); 812 hibernate_reserved_size_init(); 813 pm_states_init(); 814 power_kobj = kobject_create_and_add("power", NULL); 815 if (!power_kobj) 816 return -ENOMEM; 817 error = sysfs_create_group(power_kobj, &attr_group); 818 if (error) 819 return error; 820 pm_print_times_init(); 821 return pm_autosleep_init(); 822 } 823 824 core_initcall(pm_init); 825