1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * kernel/power/main.c - PM subsystem core functionality. 4 * 5 * Copyright (c) 2003 Patrick Mochel 6 * Copyright (c) 2003 Open Source Development Lab 7 */ 8 9 #include <linux/export.h> 10 #include <linux/kobject.h> 11 #include <linux/string.h> 12 #include <linux/pm-trace.h> 13 #include <linux/workqueue.h> 14 #include <linux/debugfs.h> 15 #include <linux/seq_file.h> 16 #include <linux/suspend.h> 17 #include <linux/syscalls.h> 18 #include <linux/pm_runtime.h> 19 20 #include "power.h" 21 22 #ifdef CONFIG_PM_SLEEP 23 24 void lock_system_sleep(void) 25 { 26 current->flags |= PF_FREEZER_SKIP; 27 mutex_lock(&system_transition_mutex); 28 } 29 EXPORT_SYMBOL_GPL(lock_system_sleep); 30 31 void unlock_system_sleep(void) 32 { 33 /* 34 * Don't use freezer_count() because we don't want the call to 35 * try_to_freeze() here. 36 * 37 * Reason: 38 * Fundamentally, we just don't need it, because freezing condition 39 * doesn't come into effect until we release the 40 * system_transition_mutex lock, since the freezer always works with 41 * system_transition_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(&system_transition_mutex); 51 } 52 EXPORT_SYMBOL_GPL(unlock_system_sleep); 53 54 void ksys_sync_helper(void) 55 { 56 ktime_t start; 57 long elapsed_msecs; 58 59 start = ktime_get(); 60 ksys_sync(); 61 elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); 62 pr_info("Filesystems sync: %ld.%03ld seconds\n", 63 elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC); 64 } 65 EXPORT_SYMBOL_GPL(ksys_sync_helper); 66 67 /* Routines for PM-transition notifications */ 68 69 static BLOCKING_NOTIFIER_HEAD(pm_chain_head); 70 71 int register_pm_notifier(struct notifier_block *nb) 72 { 73 return blocking_notifier_chain_register(&pm_chain_head, nb); 74 } 75 EXPORT_SYMBOL_GPL(register_pm_notifier); 76 77 int unregister_pm_notifier(struct notifier_block *nb) 78 { 79 return blocking_notifier_chain_unregister(&pm_chain_head, nb); 80 } 81 EXPORT_SYMBOL_GPL(unregister_pm_notifier); 82 83 int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down) 84 { 85 int ret; 86 87 ret = blocking_notifier_call_chain_robust(&pm_chain_head, val_up, val_down, NULL); 88 89 return notifier_to_errno(ret); 90 } 91 92 int pm_notifier_call_chain(unsigned long val) 93 { 94 return blocking_notifier_call_chain(&pm_chain_head, val, NULL); 95 } 96 97 /* If set, devices may be suspended and resumed asynchronously. */ 98 int pm_async_enabled = 1; 99 100 static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr, 101 char *buf) 102 { 103 return sprintf(buf, "%d\n", pm_async_enabled); 104 } 105 106 static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr, 107 const char *buf, size_t n) 108 { 109 unsigned long val; 110 111 if (kstrtoul(buf, 10, &val)) 112 return -EINVAL; 113 114 if (val > 1) 115 return -EINVAL; 116 117 pm_async_enabled = val; 118 return n; 119 } 120 121 power_attr(pm_async); 122 123 #ifdef CONFIG_SUSPEND 124 static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr, 125 char *buf) 126 { 127 char *s = buf; 128 suspend_state_t i; 129 130 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) 131 if (mem_sleep_states[i]) { 132 const char *label = mem_sleep_states[i]; 133 134 if (mem_sleep_current == i) 135 s += sprintf(s, "[%s] ", label); 136 else 137 s += sprintf(s, "%s ", label); 138 } 139 140 /* Convert the last space to a newline if needed. */ 141 if (s != buf) 142 *(s-1) = '\n'; 143 144 return (s - buf); 145 } 146 147 static suspend_state_t decode_suspend_state(const char *buf, size_t n) 148 { 149 suspend_state_t state; 150 char *p; 151 int len; 152 153 p = memchr(buf, '\n', n); 154 len = p ? p - buf : n; 155 156 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) { 157 const char *label = mem_sleep_states[state]; 158 159 if (label && len == strlen(label) && !strncmp(buf, label, len)) 160 return state; 161 } 162 163 return PM_SUSPEND_ON; 164 } 165 166 static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr, 167 const char *buf, size_t n) 168 { 169 suspend_state_t state; 170 int error; 171 172 error = pm_autosleep_lock(); 173 if (error) 174 return error; 175 176 if (pm_autosleep_state() > PM_SUSPEND_ON) { 177 error = -EBUSY; 178 goto out; 179 } 180 181 state = decode_suspend_state(buf, n); 182 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON) 183 mem_sleep_current = state; 184 else 185 error = -EINVAL; 186 187 out: 188 pm_autosleep_unlock(); 189 return error ? error : n; 190 } 191 192 power_attr(mem_sleep); 193 194 /* 195 * sync_on_suspend: invoke ksys_sync_helper() before suspend. 196 * 197 * show() returns whether ksys_sync_helper() is invoked before suspend. 198 * store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it. 199 */ 200 bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC); 201 202 static ssize_t sync_on_suspend_show(struct kobject *kobj, 203 struct kobj_attribute *attr, char *buf) 204 { 205 return sprintf(buf, "%d\n", sync_on_suspend_enabled); 206 } 207 208 static ssize_t sync_on_suspend_store(struct kobject *kobj, 209 struct kobj_attribute *attr, 210 const char *buf, size_t n) 211 { 212 unsigned long val; 213 214 if (kstrtoul(buf, 10, &val)) 215 return -EINVAL; 216 217 if (val > 1) 218 return -EINVAL; 219 220 sync_on_suspend_enabled = !!val; 221 return n; 222 } 223 224 power_attr(sync_on_suspend); 225 #endif /* CONFIG_SUSPEND */ 226 227 #ifdef CONFIG_PM_SLEEP_DEBUG 228 int pm_test_level = TEST_NONE; 229 230 static const char * const pm_tests[__TEST_AFTER_LAST] = { 231 [TEST_NONE] = "none", 232 [TEST_CORE] = "core", 233 [TEST_CPUS] = "processors", 234 [TEST_PLATFORM] = "platform", 235 [TEST_DEVICES] = "devices", 236 [TEST_FREEZER] = "freezer", 237 }; 238 239 static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr, 240 char *buf) 241 { 242 char *s = buf; 243 int level; 244 245 for (level = TEST_FIRST; level <= TEST_MAX; level++) 246 if (pm_tests[level]) { 247 if (level == pm_test_level) 248 s += sprintf(s, "[%s] ", pm_tests[level]); 249 else 250 s += sprintf(s, "%s ", pm_tests[level]); 251 } 252 253 if (s != buf) 254 /* convert the last space to a newline */ 255 *(s-1) = '\n'; 256 257 return (s - buf); 258 } 259 260 static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, 261 const char *buf, size_t n) 262 { 263 const char * const *s; 264 int level; 265 char *p; 266 int len; 267 int error = -EINVAL; 268 269 p = memchr(buf, '\n', n); 270 len = p ? p - buf : n; 271 272 lock_system_sleep(); 273 274 level = TEST_FIRST; 275 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) 276 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) { 277 pm_test_level = level; 278 error = 0; 279 break; 280 } 281 282 unlock_system_sleep(); 283 284 return error ? error : n; 285 } 286 287 power_attr(pm_test); 288 #endif /* CONFIG_PM_SLEEP_DEBUG */ 289 290 static char *suspend_step_name(enum suspend_stat_step step) 291 { 292 switch (step) { 293 case SUSPEND_FREEZE: 294 return "freeze"; 295 case SUSPEND_PREPARE: 296 return "prepare"; 297 case SUSPEND_SUSPEND: 298 return "suspend"; 299 case SUSPEND_SUSPEND_NOIRQ: 300 return "suspend_noirq"; 301 case SUSPEND_RESUME_NOIRQ: 302 return "resume_noirq"; 303 case SUSPEND_RESUME: 304 return "resume"; 305 default: 306 return ""; 307 } 308 } 309 310 #define suspend_attr(_name) \ 311 static ssize_t _name##_show(struct kobject *kobj, \ 312 struct kobj_attribute *attr, char *buf) \ 313 { \ 314 return sprintf(buf, "%d\n", suspend_stats._name); \ 315 } \ 316 static struct kobj_attribute _name = __ATTR_RO(_name) 317 318 suspend_attr(success); 319 suspend_attr(fail); 320 suspend_attr(failed_freeze); 321 suspend_attr(failed_prepare); 322 suspend_attr(failed_suspend); 323 suspend_attr(failed_suspend_late); 324 suspend_attr(failed_suspend_noirq); 325 suspend_attr(failed_resume); 326 suspend_attr(failed_resume_early); 327 suspend_attr(failed_resume_noirq); 328 329 static ssize_t last_failed_dev_show(struct kobject *kobj, 330 struct kobj_attribute *attr, char *buf) 331 { 332 int index; 333 char *last_failed_dev = NULL; 334 335 index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1; 336 index %= REC_FAILED_NUM; 337 last_failed_dev = suspend_stats.failed_devs[index]; 338 339 return sprintf(buf, "%s\n", last_failed_dev); 340 } 341 static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev); 342 343 static ssize_t last_failed_errno_show(struct kobject *kobj, 344 struct kobj_attribute *attr, char *buf) 345 { 346 int index; 347 int last_failed_errno; 348 349 index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1; 350 index %= REC_FAILED_NUM; 351 last_failed_errno = suspend_stats.errno[index]; 352 353 return sprintf(buf, "%d\n", last_failed_errno); 354 } 355 static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno); 356 357 static ssize_t last_failed_step_show(struct kobject *kobj, 358 struct kobj_attribute *attr, char *buf) 359 { 360 int index; 361 enum suspend_stat_step step; 362 char *last_failed_step = NULL; 363 364 index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1; 365 index %= REC_FAILED_NUM; 366 step = suspend_stats.failed_steps[index]; 367 last_failed_step = suspend_step_name(step); 368 369 return sprintf(buf, "%s\n", last_failed_step); 370 } 371 static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step); 372 373 static struct attribute *suspend_attrs[] = { 374 &success.attr, 375 &fail.attr, 376 &failed_freeze.attr, 377 &failed_prepare.attr, 378 &failed_suspend.attr, 379 &failed_suspend_late.attr, 380 &failed_suspend_noirq.attr, 381 &failed_resume.attr, 382 &failed_resume_early.attr, 383 &failed_resume_noirq.attr, 384 &last_failed_dev.attr, 385 &last_failed_errno.attr, 386 &last_failed_step.attr, 387 NULL, 388 }; 389 390 static const struct attribute_group suspend_attr_group = { 391 .name = "suspend_stats", 392 .attrs = suspend_attrs, 393 }; 394 395 #ifdef CONFIG_DEBUG_FS 396 static int suspend_stats_show(struct seq_file *s, void *unused) 397 { 398 int i, index, last_dev, last_errno, last_step; 399 400 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1; 401 last_dev %= REC_FAILED_NUM; 402 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1; 403 last_errno %= REC_FAILED_NUM; 404 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1; 405 last_step %= REC_FAILED_NUM; 406 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n" 407 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n", 408 "success", suspend_stats.success, 409 "fail", suspend_stats.fail, 410 "failed_freeze", suspend_stats.failed_freeze, 411 "failed_prepare", suspend_stats.failed_prepare, 412 "failed_suspend", suspend_stats.failed_suspend, 413 "failed_suspend_late", 414 suspend_stats.failed_suspend_late, 415 "failed_suspend_noirq", 416 suspend_stats.failed_suspend_noirq, 417 "failed_resume", suspend_stats.failed_resume, 418 "failed_resume_early", 419 suspend_stats.failed_resume_early, 420 "failed_resume_noirq", 421 suspend_stats.failed_resume_noirq); 422 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n", 423 suspend_stats.failed_devs[last_dev]); 424 for (i = 1; i < REC_FAILED_NUM; i++) { 425 index = last_dev + REC_FAILED_NUM - i; 426 index %= REC_FAILED_NUM; 427 seq_printf(s, "\t\t\t%-s\n", 428 suspend_stats.failed_devs[index]); 429 } 430 seq_printf(s, " last_failed_errno:\t%-d\n", 431 suspend_stats.errno[last_errno]); 432 for (i = 1; i < REC_FAILED_NUM; i++) { 433 index = last_errno + REC_FAILED_NUM - i; 434 index %= REC_FAILED_NUM; 435 seq_printf(s, "\t\t\t%-d\n", 436 suspend_stats.errno[index]); 437 } 438 seq_printf(s, " last_failed_step:\t%-s\n", 439 suspend_step_name( 440 suspend_stats.failed_steps[last_step])); 441 for (i = 1; i < REC_FAILED_NUM; i++) { 442 index = last_step + REC_FAILED_NUM - i; 443 index %= REC_FAILED_NUM; 444 seq_printf(s, "\t\t\t%-s\n", 445 suspend_step_name( 446 suspend_stats.failed_steps[index])); 447 } 448 449 return 0; 450 } 451 DEFINE_SHOW_ATTRIBUTE(suspend_stats); 452 453 static int __init pm_debugfs_init(void) 454 { 455 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO, 456 NULL, NULL, &suspend_stats_fops); 457 return 0; 458 } 459 460 late_initcall(pm_debugfs_init); 461 #endif /* CONFIG_DEBUG_FS */ 462 463 #endif /* CONFIG_PM_SLEEP */ 464 465 #ifdef CONFIG_PM_SLEEP_DEBUG 466 /* 467 * pm_print_times: print time taken by devices to suspend and resume. 468 * 469 * show() returns whether printing of suspend and resume times is enabled. 470 * store() accepts 0 or 1. 0 disables printing and 1 enables it. 471 */ 472 bool pm_print_times_enabled; 473 474 static ssize_t pm_print_times_show(struct kobject *kobj, 475 struct kobj_attribute *attr, char *buf) 476 { 477 return sprintf(buf, "%d\n", pm_print_times_enabled); 478 } 479 480 static ssize_t pm_print_times_store(struct kobject *kobj, 481 struct kobj_attribute *attr, 482 const char *buf, size_t n) 483 { 484 unsigned long val; 485 486 if (kstrtoul(buf, 10, &val)) 487 return -EINVAL; 488 489 if (val > 1) 490 return -EINVAL; 491 492 pm_print_times_enabled = !!val; 493 return n; 494 } 495 496 power_attr(pm_print_times); 497 498 static inline void pm_print_times_init(void) 499 { 500 pm_print_times_enabled = !!initcall_debug; 501 } 502 503 static ssize_t pm_wakeup_irq_show(struct kobject *kobj, 504 struct kobj_attribute *attr, 505 char *buf) 506 { 507 if (!pm_wakeup_irq()) 508 return -ENODATA; 509 510 return sprintf(buf, "%u\n", pm_wakeup_irq()); 511 } 512 513 power_attr_ro(pm_wakeup_irq); 514 515 bool pm_debug_messages_on __read_mostly; 516 517 static ssize_t pm_debug_messages_show(struct kobject *kobj, 518 struct kobj_attribute *attr, char *buf) 519 { 520 return sprintf(buf, "%d\n", pm_debug_messages_on); 521 } 522 523 static ssize_t pm_debug_messages_store(struct kobject *kobj, 524 struct kobj_attribute *attr, 525 const char *buf, size_t n) 526 { 527 unsigned long val; 528 529 if (kstrtoul(buf, 10, &val)) 530 return -EINVAL; 531 532 if (val > 1) 533 return -EINVAL; 534 535 pm_debug_messages_on = !!val; 536 return n; 537 } 538 539 power_attr(pm_debug_messages); 540 541 static int __init pm_debug_messages_setup(char *str) 542 { 543 pm_debug_messages_on = true; 544 return 1; 545 } 546 __setup("pm_debug_messages", pm_debug_messages_setup); 547 548 #else /* !CONFIG_PM_SLEEP_DEBUG */ 549 static inline void pm_print_times_init(void) {} 550 #endif /* CONFIG_PM_SLEEP_DEBUG */ 551 552 struct kobject *power_kobj; 553 554 /* 555 * state - control system sleep states. 556 * 557 * show() returns available sleep state labels, which may be "mem", "standby", 558 * "freeze" and "disk" (hibernation). 559 * See Documentation/admin-guide/pm/sleep-states.rst for a description of 560 * what they mean. 561 * 562 * store() accepts one of those strings, translates it into the proper 563 * enumerated value, and initiates a suspend transition. 564 */ 565 static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, 566 char *buf) 567 { 568 char *s = buf; 569 #ifdef CONFIG_SUSPEND 570 suspend_state_t i; 571 572 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) 573 if (pm_states[i]) 574 s += sprintf(s,"%s ", pm_states[i]); 575 576 #endif 577 if (hibernation_available()) 578 s += sprintf(s, "disk "); 579 if (s != buf) 580 /* convert the last space to a newline */ 581 *(s-1) = '\n'; 582 return (s - buf); 583 } 584 585 static suspend_state_t decode_state(const char *buf, size_t n) 586 { 587 #ifdef CONFIG_SUSPEND 588 suspend_state_t state; 589 #endif 590 char *p; 591 int len; 592 593 p = memchr(buf, '\n', n); 594 len = p ? p - buf : n; 595 596 /* Check hibernation first. */ 597 if (len == 4 && str_has_prefix(buf, "disk")) 598 return PM_SUSPEND_MAX; 599 600 #ifdef CONFIG_SUSPEND 601 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) { 602 const char *label = pm_states[state]; 603 604 if (label && len == strlen(label) && !strncmp(buf, label, len)) 605 return state; 606 } 607 #endif 608 609 return PM_SUSPEND_ON; 610 } 611 612 static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, 613 const char *buf, size_t n) 614 { 615 suspend_state_t state; 616 int error; 617 618 error = pm_autosleep_lock(); 619 if (error) 620 return error; 621 622 if (pm_autosleep_state() > PM_SUSPEND_ON) { 623 error = -EBUSY; 624 goto out; 625 } 626 627 state = decode_state(buf, n); 628 if (state < PM_SUSPEND_MAX) { 629 if (state == PM_SUSPEND_MEM) 630 state = mem_sleep_current; 631 632 error = pm_suspend(state); 633 } else if (state == PM_SUSPEND_MAX) { 634 error = hibernate(); 635 } else { 636 error = -EINVAL; 637 } 638 639 out: 640 pm_autosleep_unlock(); 641 return error ? error : n; 642 } 643 644 power_attr(state); 645 646 #ifdef CONFIG_PM_SLEEP 647 /* 648 * The 'wakeup_count' attribute, along with the functions defined in 649 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be 650 * handled in a non-racy way. 651 * 652 * If a wakeup event occurs when the system is in a sleep state, it simply is 653 * woken up. In turn, if an event that would wake the system up from a sleep 654 * state occurs when it is undergoing a transition to that sleep state, the 655 * transition should be aborted. Moreover, if such an event occurs when the 656 * system is in the working state, an attempt to start a transition to the 657 * given sleep state should fail during certain period after the detection of 658 * the event. Using the 'state' attribute alone is not sufficient to satisfy 659 * these requirements, because a wakeup event may occur exactly when 'state' 660 * is being written to and may be delivered to user space right before it is 661 * frozen, so the event will remain only partially processed until the system is 662 * woken up by another event. In particular, it won't cause the transition to 663 * a sleep state to be aborted. 664 * 665 * This difficulty may be overcome if user space uses 'wakeup_count' before 666 * writing to 'state'. It first should read from 'wakeup_count' and store 667 * the read value. Then, after carrying out its own preparations for the system 668 * transition to a sleep state, it should write the stored value to 669 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since 670 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it 671 * is allowed to write to 'state', but the transition will be aborted if there 672 * are any wakeup events detected after 'wakeup_count' was written to. 673 */ 674 675 static ssize_t wakeup_count_show(struct kobject *kobj, 676 struct kobj_attribute *attr, 677 char *buf) 678 { 679 unsigned int val; 680 681 return pm_get_wakeup_count(&val, true) ? 682 sprintf(buf, "%u\n", val) : -EINTR; 683 } 684 685 static ssize_t wakeup_count_store(struct kobject *kobj, 686 struct kobj_attribute *attr, 687 const char *buf, size_t n) 688 { 689 unsigned int val; 690 int error; 691 692 error = pm_autosleep_lock(); 693 if (error) 694 return error; 695 696 if (pm_autosleep_state() > PM_SUSPEND_ON) { 697 error = -EBUSY; 698 goto out; 699 } 700 701 error = -EINVAL; 702 if (sscanf(buf, "%u", &val) == 1) { 703 if (pm_save_wakeup_count(val)) 704 error = n; 705 else 706 pm_print_active_wakeup_sources(); 707 } 708 709 out: 710 pm_autosleep_unlock(); 711 return error; 712 } 713 714 power_attr(wakeup_count); 715 716 #ifdef CONFIG_PM_AUTOSLEEP 717 static ssize_t autosleep_show(struct kobject *kobj, 718 struct kobj_attribute *attr, 719 char *buf) 720 { 721 suspend_state_t state = pm_autosleep_state(); 722 723 if (state == PM_SUSPEND_ON) 724 return sprintf(buf, "off\n"); 725 726 #ifdef CONFIG_SUSPEND 727 if (state < PM_SUSPEND_MAX) 728 return sprintf(buf, "%s\n", pm_states[state] ? 729 pm_states[state] : "error"); 730 #endif 731 #ifdef CONFIG_HIBERNATION 732 return sprintf(buf, "disk\n"); 733 #else 734 return sprintf(buf, "error"); 735 #endif 736 } 737 738 static ssize_t autosleep_store(struct kobject *kobj, 739 struct kobj_attribute *attr, 740 const char *buf, size_t n) 741 { 742 suspend_state_t state = decode_state(buf, n); 743 int error; 744 745 if (state == PM_SUSPEND_ON 746 && strcmp(buf, "off") && strcmp(buf, "off\n")) 747 return -EINVAL; 748 749 if (state == PM_SUSPEND_MEM) 750 state = mem_sleep_current; 751 752 error = pm_autosleep_set_state(state); 753 return error ? error : n; 754 } 755 756 power_attr(autosleep); 757 #endif /* CONFIG_PM_AUTOSLEEP */ 758 759 #ifdef CONFIG_PM_WAKELOCKS 760 static ssize_t wake_lock_show(struct kobject *kobj, 761 struct kobj_attribute *attr, 762 char *buf) 763 { 764 return pm_show_wakelocks(buf, true); 765 } 766 767 static ssize_t wake_lock_store(struct kobject *kobj, 768 struct kobj_attribute *attr, 769 const char *buf, size_t n) 770 { 771 int error = pm_wake_lock(buf); 772 return error ? error : n; 773 } 774 775 power_attr(wake_lock); 776 777 static ssize_t wake_unlock_show(struct kobject *kobj, 778 struct kobj_attribute *attr, 779 char *buf) 780 { 781 return pm_show_wakelocks(buf, false); 782 } 783 784 static ssize_t wake_unlock_store(struct kobject *kobj, 785 struct kobj_attribute *attr, 786 const char *buf, size_t n) 787 { 788 int error = pm_wake_unlock(buf); 789 return error ? error : n; 790 } 791 792 power_attr(wake_unlock); 793 794 #endif /* CONFIG_PM_WAKELOCKS */ 795 #endif /* CONFIG_PM_SLEEP */ 796 797 #ifdef CONFIG_PM_TRACE 798 int pm_trace_enabled; 799 800 static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr, 801 char *buf) 802 { 803 return sprintf(buf, "%d\n", pm_trace_enabled); 804 } 805 806 static ssize_t 807 pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr, 808 const char *buf, size_t n) 809 { 810 int val; 811 812 if (sscanf(buf, "%d", &val) == 1) { 813 pm_trace_enabled = !!val; 814 if (pm_trace_enabled) { 815 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n" 816 "PM: Correct system time has to be restored manually after resume.\n"); 817 } 818 return n; 819 } 820 return -EINVAL; 821 } 822 823 power_attr(pm_trace); 824 825 static ssize_t pm_trace_dev_match_show(struct kobject *kobj, 826 struct kobj_attribute *attr, 827 char *buf) 828 { 829 return show_trace_dev_match(buf, PAGE_SIZE); 830 } 831 832 power_attr_ro(pm_trace_dev_match); 833 834 #endif /* CONFIG_PM_TRACE */ 835 836 #ifdef CONFIG_FREEZER 837 static ssize_t pm_freeze_timeout_show(struct kobject *kobj, 838 struct kobj_attribute *attr, char *buf) 839 { 840 return sprintf(buf, "%u\n", freeze_timeout_msecs); 841 } 842 843 static ssize_t pm_freeze_timeout_store(struct kobject *kobj, 844 struct kobj_attribute *attr, 845 const char *buf, size_t n) 846 { 847 unsigned long val; 848 849 if (kstrtoul(buf, 10, &val)) 850 return -EINVAL; 851 852 freeze_timeout_msecs = val; 853 return n; 854 } 855 856 power_attr(pm_freeze_timeout); 857 858 #endif /* CONFIG_FREEZER*/ 859 860 static struct attribute * g[] = { 861 &state_attr.attr, 862 #ifdef CONFIG_PM_TRACE 863 &pm_trace_attr.attr, 864 &pm_trace_dev_match_attr.attr, 865 #endif 866 #ifdef CONFIG_PM_SLEEP 867 &pm_async_attr.attr, 868 &wakeup_count_attr.attr, 869 #ifdef CONFIG_SUSPEND 870 &mem_sleep_attr.attr, 871 &sync_on_suspend_attr.attr, 872 #endif 873 #ifdef CONFIG_PM_AUTOSLEEP 874 &autosleep_attr.attr, 875 #endif 876 #ifdef CONFIG_PM_WAKELOCKS 877 &wake_lock_attr.attr, 878 &wake_unlock_attr.attr, 879 #endif 880 #ifdef CONFIG_PM_SLEEP_DEBUG 881 &pm_test_attr.attr, 882 &pm_print_times_attr.attr, 883 &pm_wakeup_irq_attr.attr, 884 &pm_debug_messages_attr.attr, 885 #endif 886 #endif 887 #ifdef CONFIG_FREEZER 888 &pm_freeze_timeout_attr.attr, 889 #endif 890 NULL, 891 }; 892 893 static const struct attribute_group attr_group = { 894 .attrs = g, 895 }; 896 897 static const struct attribute_group *attr_groups[] = { 898 &attr_group, 899 #ifdef CONFIG_PM_SLEEP 900 &suspend_attr_group, 901 #endif 902 NULL, 903 }; 904 905 struct workqueue_struct *pm_wq; 906 EXPORT_SYMBOL_GPL(pm_wq); 907 908 static int __init pm_start_workqueue(void) 909 { 910 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0); 911 912 return pm_wq ? 0 : -ENOMEM; 913 } 914 915 static int __init pm_init(void) 916 { 917 int error = pm_start_workqueue(); 918 if (error) 919 return error; 920 hibernate_image_size_init(); 921 hibernate_reserved_size_init(); 922 pm_states_init(); 923 power_kobj = kobject_create_and_add("power", NULL); 924 if (!power_kobj) 925 return -ENOMEM; 926 error = sysfs_create_groups(power_kobj, attr_groups); 927 if (error) 928 return error; 929 pm_print_times_init(); 930 return pm_autosleep_init(); 931 } 932 933 core_initcall(pm_init); 934