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/acpi.h> |
10 | #include <linux/export.h> |
11 | #include <linux/kobject.h> |
12 | #include <linux/string.h> |
13 | #include <linux/pm-trace.h> |
14 | #include <linux/workqueue.h> |
15 | #include <linux/debugfs.h> |
16 | #include <linux/seq_file.h> |
17 | #include <linux/suspend.h> |
18 | #include <linux/syscalls.h> |
19 | #include <linux/pm_runtime.h> |
20 | |
21 | #include "power.h" |
22 | |
23 | #ifdef CONFIG_PM_SLEEP |
24 | /* |
25 | * The following functions are used by the suspend/hibernate code to temporarily |
26 | * change gfp_allowed_mask in order to avoid using I/O during memory allocations |
27 | * while devices are suspended. To avoid races with the suspend/hibernate code, |
28 | * they should always be called with system_transition_mutex held |
29 | * (gfp_allowed_mask also should only be modified with system_transition_mutex |
30 | * held, unless the suspend/hibernate code is guaranteed not to run in parallel |
31 | * with that modification). |
32 | */ |
33 | static gfp_t saved_gfp_mask; |
34 | |
35 | void pm_restore_gfp_mask(void) |
36 | { |
37 | WARN_ON(!mutex_is_locked(&system_transition_mutex)); |
38 | if (saved_gfp_mask) { |
39 | gfp_allowed_mask = saved_gfp_mask; |
40 | saved_gfp_mask = 0; |
41 | } |
42 | } |
43 | |
44 | void pm_restrict_gfp_mask(void) |
45 | { |
46 | WARN_ON(!mutex_is_locked(&system_transition_mutex)); |
47 | WARN_ON(saved_gfp_mask); |
48 | saved_gfp_mask = gfp_allowed_mask; |
49 | gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS); |
50 | } |
51 | |
52 | unsigned int lock_system_sleep(void) |
53 | { |
54 | unsigned int flags = current->flags; |
55 | current->flags |= PF_NOFREEZE; |
56 | mutex_lock(&system_transition_mutex); |
57 | return flags; |
58 | } |
59 | EXPORT_SYMBOL_GPL(lock_system_sleep); |
60 | |
61 | void unlock_system_sleep(unsigned int flags) |
62 | { |
63 | /* |
64 | * Don't use freezer_count() because we don't want the call to |
65 | * try_to_freeze() here. |
66 | * |
67 | * Reason: |
68 | * Fundamentally, we just don't need it, because freezing condition |
69 | * doesn't come into effect until we release the |
70 | * system_transition_mutex lock, since the freezer always works with |
71 | * system_transition_mutex held. |
72 | * |
73 | * More importantly, in the case of hibernation, |
74 | * unlock_system_sleep() gets called in snapshot_read() and |
75 | * snapshot_write() when the freezing condition is still in effect. |
76 | * Which means, if we use try_to_freeze() here, it would make them |
77 | * enter the refrigerator, thus causing hibernation to lockup. |
78 | */ |
79 | if (!(flags & PF_NOFREEZE)) |
80 | current->flags &= ~PF_NOFREEZE; |
81 | mutex_unlock(lock: &system_transition_mutex); |
82 | } |
83 | EXPORT_SYMBOL_GPL(unlock_system_sleep); |
84 | |
85 | void ksys_sync_helper(void) |
86 | { |
87 | ktime_t start; |
88 | long elapsed_msecs; |
89 | |
90 | start = ktime_get(); |
91 | ksys_sync(); |
92 | elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); |
93 | pr_info("Filesystems sync: %ld.%03ld seconds\n" , |
94 | elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC); |
95 | } |
96 | EXPORT_SYMBOL_GPL(ksys_sync_helper); |
97 | |
98 | /* Routines for PM-transition notifications */ |
99 | |
100 | static BLOCKING_NOTIFIER_HEAD(pm_chain_head); |
101 | |
102 | int register_pm_notifier(struct notifier_block *nb) |
103 | { |
104 | return blocking_notifier_chain_register(nh: &pm_chain_head, nb); |
105 | } |
106 | EXPORT_SYMBOL_GPL(register_pm_notifier); |
107 | |
108 | int unregister_pm_notifier(struct notifier_block *nb) |
109 | { |
110 | return blocking_notifier_chain_unregister(nh: &pm_chain_head, nb); |
111 | } |
112 | EXPORT_SYMBOL_GPL(unregister_pm_notifier); |
113 | |
114 | void pm_report_hw_sleep_time(u64 t) |
115 | { |
116 | suspend_stats.last_hw_sleep = t; |
117 | suspend_stats.total_hw_sleep += t; |
118 | } |
119 | EXPORT_SYMBOL_GPL(pm_report_hw_sleep_time); |
120 | |
121 | void pm_report_max_hw_sleep(u64 t) |
122 | { |
123 | suspend_stats.max_hw_sleep = t; |
124 | } |
125 | EXPORT_SYMBOL_GPL(pm_report_max_hw_sleep); |
126 | |
127 | int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down) |
128 | { |
129 | int ret; |
130 | |
131 | ret = blocking_notifier_call_chain_robust(nh: &pm_chain_head, val_up, val_down, NULL); |
132 | |
133 | return notifier_to_errno(ret); |
134 | } |
135 | |
136 | int pm_notifier_call_chain(unsigned long val) |
137 | { |
138 | return blocking_notifier_call_chain(nh: &pm_chain_head, val, NULL); |
139 | } |
140 | |
141 | /* If set, devices may be suspended and resumed asynchronously. */ |
142 | int pm_async_enabled = 1; |
143 | |
144 | static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr, |
145 | char *buf) |
146 | { |
147 | return sprintf(buf, fmt: "%d\n" , pm_async_enabled); |
148 | } |
149 | |
150 | static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr, |
151 | const char *buf, size_t n) |
152 | { |
153 | unsigned long val; |
154 | |
155 | if (kstrtoul(s: buf, base: 10, res: &val)) |
156 | return -EINVAL; |
157 | |
158 | if (val > 1) |
159 | return -EINVAL; |
160 | |
161 | pm_async_enabled = val; |
162 | return n; |
163 | } |
164 | |
165 | power_attr(pm_async); |
166 | |
167 | #ifdef CONFIG_SUSPEND |
168 | static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr, |
169 | char *buf) |
170 | { |
171 | char *s = buf; |
172 | suspend_state_t i; |
173 | |
174 | for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) { |
175 | if (i >= PM_SUSPEND_MEM && cxl_mem_active()) |
176 | continue; |
177 | if (mem_sleep_states[i]) { |
178 | const char *label = mem_sleep_states[i]; |
179 | |
180 | if (mem_sleep_current == i) |
181 | s += sprintf(buf: s, fmt: "[%s] " , label); |
182 | else |
183 | s += sprintf(buf: s, fmt: "%s " , label); |
184 | } |
185 | } |
186 | |
187 | /* Convert the last space to a newline if needed. */ |
188 | if (s != buf) |
189 | *(s-1) = '\n'; |
190 | |
191 | return (s - buf); |
192 | } |
193 | |
194 | static suspend_state_t decode_suspend_state(const char *buf, size_t n) |
195 | { |
196 | suspend_state_t state; |
197 | char *p; |
198 | int len; |
199 | |
200 | p = memchr(p: buf, c: '\n', size: n); |
201 | len = p ? p - buf : n; |
202 | |
203 | for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) { |
204 | const char *label = mem_sleep_states[state]; |
205 | |
206 | if (label && len == strlen(label) && !strncmp(buf, label, len)) |
207 | return state; |
208 | } |
209 | |
210 | return PM_SUSPEND_ON; |
211 | } |
212 | |
213 | static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr, |
214 | const char *buf, size_t n) |
215 | { |
216 | suspend_state_t state; |
217 | int error; |
218 | |
219 | error = pm_autosleep_lock(); |
220 | if (error) |
221 | return error; |
222 | |
223 | if (pm_autosleep_state() > PM_SUSPEND_ON) { |
224 | error = -EBUSY; |
225 | goto out; |
226 | } |
227 | |
228 | state = decode_suspend_state(buf, n); |
229 | if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON) |
230 | mem_sleep_current = state; |
231 | else |
232 | error = -EINVAL; |
233 | |
234 | out: |
235 | pm_autosleep_unlock(); |
236 | return error ? error : n; |
237 | } |
238 | |
239 | power_attr(mem_sleep); |
240 | |
241 | /* |
242 | * sync_on_suspend: invoke ksys_sync_helper() before suspend. |
243 | * |
244 | * show() returns whether ksys_sync_helper() is invoked before suspend. |
245 | * store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it. |
246 | */ |
247 | bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC); |
248 | |
249 | static ssize_t sync_on_suspend_show(struct kobject *kobj, |
250 | struct kobj_attribute *attr, char *buf) |
251 | { |
252 | return sprintf(buf, fmt: "%d\n" , sync_on_suspend_enabled); |
253 | } |
254 | |
255 | static ssize_t sync_on_suspend_store(struct kobject *kobj, |
256 | struct kobj_attribute *attr, |
257 | const char *buf, size_t n) |
258 | { |
259 | unsigned long val; |
260 | |
261 | if (kstrtoul(s: buf, base: 10, res: &val)) |
262 | return -EINVAL; |
263 | |
264 | if (val > 1) |
265 | return -EINVAL; |
266 | |
267 | sync_on_suspend_enabled = !!val; |
268 | return n; |
269 | } |
270 | |
271 | power_attr(sync_on_suspend); |
272 | #endif /* CONFIG_SUSPEND */ |
273 | |
274 | #ifdef CONFIG_PM_SLEEP_DEBUG |
275 | int pm_test_level = TEST_NONE; |
276 | |
277 | static const char * const pm_tests[__TEST_AFTER_LAST] = { |
278 | [TEST_NONE] = "none" , |
279 | [TEST_CORE] = "core" , |
280 | [TEST_CPUS] = "processors" , |
281 | [TEST_PLATFORM] = "platform" , |
282 | [TEST_DEVICES] = "devices" , |
283 | [TEST_FREEZER] = "freezer" , |
284 | }; |
285 | |
286 | static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr, |
287 | char *buf) |
288 | { |
289 | char *s = buf; |
290 | int level; |
291 | |
292 | for (level = TEST_FIRST; level <= TEST_MAX; level++) |
293 | if (pm_tests[level]) { |
294 | if (level == pm_test_level) |
295 | s += sprintf(buf: s, fmt: "[%s] " , pm_tests[level]); |
296 | else |
297 | s += sprintf(buf: s, fmt: "%s " , pm_tests[level]); |
298 | } |
299 | |
300 | if (s != buf) |
301 | /* convert the last space to a newline */ |
302 | *(s-1) = '\n'; |
303 | |
304 | return (s - buf); |
305 | } |
306 | |
307 | static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, |
308 | const char *buf, size_t n) |
309 | { |
310 | unsigned int sleep_flags; |
311 | const char * const *s; |
312 | int error = -EINVAL; |
313 | int level; |
314 | char *p; |
315 | int len; |
316 | |
317 | p = memchr(p: buf, c: '\n', size: n); |
318 | len = p ? p - buf : n; |
319 | |
320 | sleep_flags = lock_system_sleep(); |
321 | |
322 | level = TEST_FIRST; |
323 | for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) |
324 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) { |
325 | pm_test_level = level; |
326 | error = 0; |
327 | break; |
328 | } |
329 | |
330 | unlock_system_sleep(sleep_flags); |
331 | |
332 | return error ? error : n; |
333 | } |
334 | |
335 | power_attr(pm_test); |
336 | #endif /* CONFIG_PM_SLEEP_DEBUG */ |
337 | |
338 | static char *suspend_step_name(enum suspend_stat_step step) |
339 | { |
340 | switch (step) { |
341 | case SUSPEND_FREEZE: |
342 | return "freeze" ; |
343 | case SUSPEND_PREPARE: |
344 | return "prepare" ; |
345 | case SUSPEND_SUSPEND: |
346 | return "suspend" ; |
347 | case SUSPEND_SUSPEND_NOIRQ: |
348 | return "suspend_noirq" ; |
349 | case SUSPEND_RESUME_NOIRQ: |
350 | return "resume_noirq" ; |
351 | case SUSPEND_RESUME: |
352 | return "resume" ; |
353 | default: |
354 | return "" ; |
355 | } |
356 | } |
357 | |
358 | #define suspend_attr(_name, format_str) \ |
359 | static ssize_t _name##_show(struct kobject *kobj, \ |
360 | struct kobj_attribute *attr, char *buf) \ |
361 | { \ |
362 | return sprintf(buf, format_str, suspend_stats._name); \ |
363 | } \ |
364 | static struct kobj_attribute _name = __ATTR_RO(_name) |
365 | |
366 | suspend_attr(success, "%d\n" ); |
367 | suspend_attr(fail, "%d\n" ); |
368 | suspend_attr(failed_freeze, "%d\n" ); |
369 | suspend_attr(failed_prepare, "%d\n" ); |
370 | suspend_attr(failed_suspend, "%d\n" ); |
371 | suspend_attr(failed_suspend_late, "%d\n" ); |
372 | suspend_attr(failed_suspend_noirq, "%d\n" ); |
373 | suspend_attr(failed_resume, "%d\n" ); |
374 | suspend_attr(failed_resume_early, "%d\n" ); |
375 | suspend_attr(failed_resume_noirq, "%d\n" ); |
376 | suspend_attr(last_hw_sleep, "%llu\n" ); |
377 | suspend_attr(total_hw_sleep, "%llu\n" ); |
378 | suspend_attr(max_hw_sleep, "%llu\n" ); |
379 | |
380 | static ssize_t last_failed_dev_show(struct kobject *kobj, |
381 | struct kobj_attribute *attr, char *buf) |
382 | { |
383 | int index; |
384 | char *last_failed_dev = NULL; |
385 | |
386 | index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1; |
387 | index %= REC_FAILED_NUM; |
388 | last_failed_dev = suspend_stats.failed_devs[index]; |
389 | |
390 | return sprintf(buf, fmt: "%s\n" , last_failed_dev); |
391 | } |
392 | static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev); |
393 | |
394 | static ssize_t last_failed_errno_show(struct kobject *kobj, |
395 | struct kobj_attribute *attr, char *buf) |
396 | { |
397 | int index; |
398 | int last_failed_errno; |
399 | |
400 | index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1; |
401 | index %= REC_FAILED_NUM; |
402 | last_failed_errno = suspend_stats.errno[index]; |
403 | |
404 | return sprintf(buf, fmt: "%d\n" , last_failed_errno); |
405 | } |
406 | static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno); |
407 | |
408 | static ssize_t last_failed_step_show(struct kobject *kobj, |
409 | struct kobj_attribute *attr, char *buf) |
410 | { |
411 | int index; |
412 | enum suspend_stat_step step; |
413 | char *last_failed_step = NULL; |
414 | |
415 | index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1; |
416 | index %= REC_FAILED_NUM; |
417 | step = suspend_stats.failed_steps[index]; |
418 | last_failed_step = suspend_step_name(step); |
419 | |
420 | return sprintf(buf, fmt: "%s\n" , last_failed_step); |
421 | } |
422 | static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step); |
423 | |
424 | static struct attribute *suspend_attrs[] = { |
425 | &success.attr, |
426 | &fail.attr, |
427 | &failed_freeze.attr, |
428 | &failed_prepare.attr, |
429 | &failed_suspend.attr, |
430 | &failed_suspend_late.attr, |
431 | &failed_suspend_noirq.attr, |
432 | &failed_resume.attr, |
433 | &failed_resume_early.attr, |
434 | &failed_resume_noirq.attr, |
435 | &last_failed_dev.attr, |
436 | &last_failed_errno.attr, |
437 | &last_failed_step.attr, |
438 | &last_hw_sleep.attr, |
439 | &total_hw_sleep.attr, |
440 | &max_hw_sleep.attr, |
441 | NULL, |
442 | }; |
443 | |
444 | static umode_t suspend_attr_is_visible(struct kobject *kobj, struct attribute *attr, int idx) |
445 | { |
446 | if (attr != &last_hw_sleep.attr && |
447 | attr != &total_hw_sleep.attr && |
448 | attr != &max_hw_sleep.attr) |
449 | return 0444; |
450 | |
451 | #ifdef CONFIG_ACPI |
452 | if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) |
453 | return 0444; |
454 | #endif |
455 | return 0; |
456 | } |
457 | |
458 | static const struct attribute_group suspend_attr_group = { |
459 | .name = "suspend_stats" , |
460 | .attrs = suspend_attrs, |
461 | .is_visible = suspend_attr_is_visible, |
462 | }; |
463 | |
464 | #ifdef CONFIG_DEBUG_FS |
465 | static int suspend_stats_show(struct seq_file *s, void *unused) |
466 | { |
467 | int i, index, last_dev, last_errno, last_step; |
468 | |
469 | last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1; |
470 | last_dev %= REC_FAILED_NUM; |
471 | last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1; |
472 | last_errno %= REC_FAILED_NUM; |
473 | last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1; |
474 | last_step %= REC_FAILED_NUM; |
475 | seq_printf(m: s, fmt: "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n" |
476 | "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n" , |
477 | "success" , suspend_stats.success, |
478 | "fail" , suspend_stats.fail, |
479 | "failed_freeze" , suspend_stats.failed_freeze, |
480 | "failed_prepare" , suspend_stats.failed_prepare, |
481 | "failed_suspend" , suspend_stats.failed_suspend, |
482 | "failed_suspend_late" , |
483 | suspend_stats.failed_suspend_late, |
484 | "failed_suspend_noirq" , |
485 | suspend_stats.failed_suspend_noirq, |
486 | "failed_resume" , suspend_stats.failed_resume, |
487 | "failed_resume_early" , |
488 | suspend_stats.failed_resume_early, |
489 | "failed_resume_noirq" , |
490 | suspend_stats.failed_resume_noirq); |
491 | seq_printf(m: s, fmt: "failures:\n last_failed_dev:\t%-s\n" , |
492 | suspend_stats.failed_devs[last_dev]); |
493 | for (i = 1; i < REC_FAILED_NUM; i++) { |
494 | index = last_dev + REC_FAILED_NUM - i; |
495 | index %= REC_FAILED_NUM; |
496 | seq_printf(m: s, fmt: "\t\t\t%-s\n" , |
497 | suspend_stats.failed_devs[index]); |
498 | } |
499 | seq_printf(m: s, fmt: " last_failed_errno:\t%-d\n" , |
500 | suspend_stats.errno[last_errno]); |
501 | for (i = 1; i < REC_FAILED_NUM; i++) { |
502 | index = last_errno + REC_FAILED_NUM - i; |
503 | index %= REC_FAILED_NUM; |
504 | seq_printf(m: s, fmt: "\t\t\t%-d\n" , |
505 | suspend_stats.errno[index]); |
506 | } |
507 | seq_printf(m: s, fmt: " last_failed_step:\t%-s\n" , |
508 | suspend_step_name( |
509 | step: suspend_stats.failed_steps[last_step])); |
510 | for (i = 1; i < REC_FAILED_NUM; i++) { |
511 | index = last_step + REC_FAILED_NUM - i; |
512 | index %= REC_FAILED_NUM; |
513 | seq_printf(m: s, fmt: "\t\t\t%-s\n" , |
514 | suspend_step_name( |
515 | step: suspend_stats.failed_steps[index])); |
516 | } |
517 | |
518 | return 0; |
519 | } |
520 | DEFINE_SHOW_ATTRIBUTE(suspend_stats); |
521 | |
522 | static int __init pm_debugfs_init(void) |
523 | { |
524 | debugfs_create_file(name: "suspend_stats" , S_IFREG | S_IRUGO, |
525 | NULL, NULL, fops: &suspend_stats_fops); |
526 | return 0; |
527 | } |
528 | |
529 | late_initcall(pm_debugfs_init); |
530 | #endif /* CONFIG_DEBUG_FS */ |
531 | |
532 | #endif /* CONFIG_PM_SLEEP */ |
533 | |
534 | #ifdef CONFIG_PM_SLEEP_DEBUG |
535 | /* |
536 | * pm_print_times: print time taken by devices to suspend and resume. |
537 | * |
538 | * show() returns whether printing of suspend and resume times is enabled. |
539 | * store() accepts 0 or 1. 0 disables printing and 1 enables it. |
540 | */ |
541 | bool pm_print_times_enabled; |
542 | |
543 | static ssize_t pm_print_times_show(struct kobject *kobj, |
544 | struct kobj_attribute *attr, char *buf) |
545 | { |
546 | return sprintf(buf, fmt: "%d\n" , pm_print_times_enabled); |
547 | } |
548 | |
549 | static ssize_t pm_print_times_store(struct kobject *kobj, |
550 | struct kobj_attribute *attr, |
551 | const char *buf, size_t n) |
552 | { |
553 | unsigned long val; |
554 | |
555 | if (kstrtoul(s: buf, base: 10, res: &val)) |
556 | return -EINVAL; |
557 | |
558 | if (val > 1) |
559 | return -EINVAL; |
560 | |
561 | pm_print_times_enabled = !!val; |
562 | return n; |
563 | } |
564 | |
565 | power_attr(pm_print_times); |
566 | |
567 | static inline void pm_print_times_init(void) |
568 | { |
569 | pm_print_times_enabled = !!initcall_debug; |
570 | } |
571 | |
572 | static ssize_t pm_wakeup_irq_show(struct kobject *kobj, |
573 | struct kobj_attribute *attr, |
574 | char *buf) |
575 | { |
576 | if (!pm_wakeup_irq()) |
577 | return -ENODATA; |
578 | |
579 | return sprintf(buf, fmt: "%u\n" , pm_wakeup_irq()); |
580 | } |
581 | |
582 | power_attr_ro(pm_wakeup_irq); |
583 | |
584 | bool pm_debug_messages_on __read_mostly; |
585 | |
586 | bool pm_debug_messages_should_print(void) |
587 | { |
588 | return pm_debug_messages_on && pm_suspend_target_state != PM_SUSPEND_ON; |
589 | } |
590 | EXPORT_SYMBOL_GPL(pm_debug_messages_should_print); |
591 | |
592 | static ssize_t pm_debug_messages_show(struct kobject *kobj, |
593 | struct kobj_attribute *attr, char *buf) |
594 | { |
595 | return sprintf(buf, fmt: "%d\n" , pm_debug_messages_on); |
596 | } |
597 | |
598 | static ssize_t pm_debug_messages_store(struct kobject *kobj, |
599 | struct kobj_attribute *attr, |
600 | const char *buf, size_t n) |
601 | { |
602 | unsigned long val; |
603 | |
604 | if (kstrtoul(s: buf, base: 10, res: &val)) |
605 | return -EINVAL; |
606 | |
607 | if (val > 1) |
608 | return -EINVAL; |
609 | |
610 | pm_debug_messages_on = !!val; |
611 | return n; |
612 | } |
613 | |
614 | power_attr(pm_debug_messages); |
615 | |
616 | static int __init pm_debug_messages_setup(char *str) |
617 | { |
618 | pm_debug_messages_on = true; |
619 | return 1; |
620 | } |
621 | __setup("pm_debug_messages" , pm_debug_messages_setup); |
622 | |
623 | #else /* !CONFIG_PM_SLEEP_DEBUG */ |
624 | static inline void pm_print_times_init(void) {} |
625 | #endif /* CONFIG_PM_SLEEP_DEBUG */ |
626 | |
627 | struct kobject *power_kobj; |
628 | |
629 | /* |
630 | * state - control system sleep states. |
631 | * |
632 | * show() returns available sleep state labels, which may be "mem", "standby", |
633 | * "freeze" and "disk" (hibernation). |
634 | * See Documentation/admin-guide/pm/sleep-states.rst for a description of |
635 | * what they mean. |
636 | * |
637 | * store() accepts one of those strings, translates it into the proper |
638 | * enumerated value, and initiates a suspend transition. |
639 | */ |
640 | static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, |
641 | char *buf) |
642 | { |
643 | char *s = buf; |
644 | #ifdef CONFIG_SUSPEND |
645 | suspend_state_t i; |
646 | |
647 | for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) |
648 | if (pm_states[i]) |
649 | s += sprintf(buf: s,fmt: "%s " , pm_states[i]); |
650 | |
651 | #endif |
652 | if (hibernation_available()) |
653 | s += sprintf(buf: s, fmt: "disk " ); |
654 | if (s != buf) |
655 | /* convert the last space to a newline */ |
656 | *(s-1) = '\n'; |
657 | return (s - buf); |
658 | } |
659 | |
660 | static suspend_state_t decode_state(const char *buf, size_t n) |
661 | { |
662 | #ifdef CONFIG_SUSPEND |
663 | suspend_state_t state; |
664 | #endif |
665 | char *p; |
666 | int len; |
667 | |
668 | p = memchr(p: buf, c: '\n', size: n); |
669 | len = p ? p - buf : n; |
670 | |
671 | /* Check hibernation first. */ |
672 | if (len == 4 && str_has_prefix(str: buf, prefix: "disk" )) |
673 | return PM_SUSPEND_MAX; |
674 | |
675 | #ifdef CONFIG_SUSPEND |
676 | for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) { |
677 | const char *label = pm_states[state]; |
678 | |
679 | if (label && len == strlen(label) && !strncmp(buf, label, len)) |
680 | return state; |
681 | } |
682 | #endif |
683 | |
684 | return PM_SUSPEND_ON; |
685 | } |
686 | |
687 | static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, |
688 | const char *buf, size_t n) |
689 | { |
690 | suspend_state_t state; |
691 | int error; |
692 | |
693 | error = pm_autosleep_lock(); |
694 | if (error) |
695 | return error; |
696 | |
697 | if (pm_autosleep_state() > PM_SUSPEND_ON) { |
698 | error = -EBUSY; |
699 | goto out; |
700 | } |
701 | |
702 | state = decode_state(buf, n); |
703 | if (state < PM_SUSPEND_MAX) { |
704 | if (state == PM_SUSPEND_MEM) |
705 | state = mem_sleep_current; |
706 | |
707 | error = pm_suspend(state); |
708 | } else if (state == PM_SUSPEND_MAX) { |
709 | error = hibernate(); |
710 | } else { |
711 | error = -EINVAL; |
712 | } |
713 | |
714 | out: |
715 | pm_autosleep_unlock(); |
716 | return error ? error : n; |
717 | } |
718 | |
719 | power_attr(state); |
720 | |
721 | #ifdef CONFIG_PM_SLEEP |
722 | /* |
723 | * The 'wakeup_count' attribute, along with the functions defined in |
724 | * drivers/base/power/wakeup.c, provides a means by which wakeup events can be |
725 | * handled in a non-racy way. |
726 | * |
727 | * If a wakeup event occurs when the system is in a sleep state, it simply is |
728 | * woken up. In turn, if an event that would wake the system up from a sleep |
729 | * state occurs when it is undergoing a transition to that sleep state, the |
730 | * transition should be aborted. Moreover, if such an event occurs when the |
731 | * system is in the working state, an attempt to start a transition to the |
732 | * given sleep state should fail during certain period after the detection of |
733 | * the event. Using the 'state' attribute alone is not sufficient to satisfy |
734 | * these requirements, because a wakeup event may occur exactly when 'state' |
735 | * is being written to and may be delivered to user space right before it is |
736 | * frozen, so the event will remain only partially processed until the system is |
737 | * woken up by another event. In particular, it won't cause the transition to |
738 | * a sleep state to be aborted. |
739 | * |
740 | * This difficulty may be overcome if user space uses 'wakeup_count' before |
741 | * writing to 'state'. It first should read from 'wakeup_count' and store |
742 | * the read value. Then, after carrying out its own preparations for the system |
743 | * transition to a sleep state, it should write the stored value to |
744 | * 'wakeup_count'. If that fails, at least one wakeup event has occurred since |
745 | * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it |
746 | * is allowed to write to 'state', but the transition will be aborted if there |
747 | * are any wakeup events detected after 'wakeup_count' was written to. |
748 | */ |
749 | |
750 | static ssize_t wakeup_count_show(struct kobject *kobj, |
751 | struct kobj_attribute *attr, |
752 | char *buf) |
753 | { |
754 | unsigned int val; |
755 | |
756 | return pm_get_wakeup_count(count: &val, block: true) ? |
757 | sprintf(buf, fmt: "%u\n" , val) : -EINTR; |
758 | } |
759 | |
760 | static ssize_t wakeup_count_store(struct kobject *kobj, |
761 | struct kobj_attribute *attr, |
762 | const char *buf, size_t n) |
763 | { |
764 | unsigned int val; |
765 | int error; |
766 | |
767 | error = pm_autosleep_lock(); |
768 | if (error) |
769 | return error; |
770 | |
771 | if (pm_autosleep_state() > PM_SUSPEND_ON) { |
772 | error = -EBUSY; |
773 | goto out; |
774 | } |
775 | |
776 | error = -EINVAL; |
777 | if (sscanf(buf, "%u" , &val) == 1) { |
778 | if (pm_save_wakeup_count(count: val)) |
779 | error = n; |
780 | else |
781 | pm_print_active_wakeup_sources(); |
782 | } |
783 | |
784 | out: |
785 | pm_autosleep_unlock(); |
786 | return error; |
787 | } |
788 | |
789 | power_attr(wakeup_count); |
790 | |
791 | #ifdef CONFIG_PM_AUTOSLEEP |
792 | static ssize_t autosleep_show(struct kobject *kobj, |
793 | struct kobj_attribute *attr, |
794 | char *buf) |
795 | { |
796 | suspend_state_t state = pm_autosleep_state(); |
797 | |
798 | if (state == PM_SUSPEND_ON) |
799 | return sprintf(buf, fmt: "off\n" ); |
800 | |
801 | #ifdef CONFIG_SUSPEND |
802 | if (state < PM_SUSPEND_MAX) |
803 | return sprintf(buf, fmt: "%s\n" , pm_states[state] ? |
804 | pm_states[state] : "error" ); |
805 | #endif |
806 | #ifdef CONFIG_HIBERNATION |
807 | return sprintf(buf, fmt: "disk\n" ); |
808 | #else |
809 | return sprintf(buf, "error" ); |
810 | #endif |
811 | } |
812 | |
813 | static ssize_t autosleep_store(struct kobject *kobj, |
814 | struct kobj_attribute *attr, |
815 | const char *buf, size_t n) |
816 | { |
817 | suspend_state_t state = decode_state(buf, n); |
818 | int error; |
819 | |
820 | if (state == PM_SUSPEND_ON |
821 | && strcmp(buf, "off" ) && strcmp(buf, "off\n" )) |
822 | return -EINVAL; |
823 | |
824 | if (state == PM_SUSPEND_MEM) |
825 | state = mem_sleep_current; |
826 | |
827 | error = pm_autosleep_set_state(state); |
828 | return error ? error : n; |
829 | } |
830 | |
831 | power_attr(autosleep); |
832 | #endif /* CONFIG_PM_AUTOSLEEP */ |
833 | |
834 | #ifdef CONFIG_PM_WAKELOCKS |
835 | static ssize_t wake_lock_show(struct kobject *kobj, |
836 | struct kobj_attribute *attr, |
837 | char *buf) |
838 | { |
839 | return pm_show_wakelocks(buf, show_active: true); |
840 | } |
841 | |
842 | static ssize_t wake_lock_store(struct kobject *kobj, |
843 | struct kobj_attribute *attr, |
844 | const char *buf, size_t n) |
845 | { |
846 | int error = pm_wake_lock(buf); |
847 | return error ? error : n; |
848 | } |
849 | |
850 | power_attr(wake_lock); |
851 | |
852 | static ssize_t wake_unlock_show(struct kobject *kobj, |
853 | struct kobj_attribute *attr, |
854 | char *buf) |
855 | { |
856 | return pm_show_wakelocks(buf, show_active: false); |
857 | } |
858 | |
859 | static ssize_t wake_unlock_store(struct kobject *kobj, |
860 | struct kobj_attribute *attr, |
861 | const char *buf, size_t n) |
862 | { |
863 | int error = pm_wake_unlock(buf); |
864 | return error ? error : n; |
865 | } |
866 | |
867 | power_attr(wake_unlock); |
868 | |
869 | #endif /* CONFIG_PM_WAKELOCKS */ |
870 | #endif /* CONFIG_PM_SLEEP */ |
871 | |
872 | #ifdef CONFIG_PM_TRACE |
873 | int pm_trace_enabled; |
874 | |
875 | static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr, |
876 | char *buf) |
877 | { |
878 | return sprintf(buf, fmt: "%d\n" , pm_trace_enabled); |
879 | } |
880 | |
881 | static ssize_t |
882 | pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr, |
883 | const char *buf, size_t n) |
884 | { |
885 | int val; |
886 | |
887 | if (sscanf(buf, "%d" , &val) == 1) { |
888 | pm_trace_enabled = !!val; |
889 | if (pm_trace_enabled) { |
890 | pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n" |
891 | "PM: Correct system time has to be restored manually after resume.\n" ); |
892 | } |
893 | return n; |
894 | } |
895 | return -EINVAL; |
896 | } |
897 | |
898 | power_attr(pm_trace); |
899 | |
900 | static ssize_t pm_trace_dev_match_show(struct kobject *kobj, |
901 | struct kobj_attribute *attr, |
902 | char *buf) |
903 | { |
904 | return show_trace_dev_match(buf, PAGE_SIZE); |
905 | } |
906 | |
907 | power_attr_ro(pm_trace_dev_match); |
908 | |
909 | #endif /* CONFIG_PM_TRACE */ |
910 | |
911 | #ifdef CONFIG_FREEZER |
912 | static ssize_t pm_freeze_timeout_show(struct kobject *kobj, |
913 | struct kobj_attribute *attr, char *buf) |
914 | { |
915 | return sprintf(buf, fmt: "%u\n" , freeze_timeout_msecs); |
916 | } |
917 | |
918 | static ssize_t pm_freeze_timeout_store(struct kobject *kobj, |
919 | struct kobj_attribute *attr, |
920 | const char *buf, size_t n) |
921 | { |
922 | unsigned long val; |
923 | |
924 | if (kstrtoul(s: buf, base: 10, res: &val)) |
925 | return -EINVAL; |
926 | |
927 | freeze_timeout_msecs = val; |
928 | return n; |
929 | } |
930 | |
931 | power_attr(pm_freeze_timeout); |
932 | |
933 | #endif /* CONFIG_FREEZER*/ |
934 | |
935 | static struct attribute * g[] = { |
936 | &state_attr.attr, |
937 | #ifdef CONFIG_PM_TRACE |
938 | &pm_trace_attr.attr, |
939 | &pm_trace_dev_match_attr.attr, |
940 | #endif |
941 | #ifdef CONFIG_PM_SLEEP |
942 | &pm_async_attr.attr, |
943 | &wakeup_count_attr.attr, |
944 | #ifdef CONFIG_SUSPEND |
945 | &mem_sleep_attr.attr, |
946 | &sync_on_suspend_attr.attr, |
947 | #endif |
948 | #ifdef CONFIG_PM_AUTOSLEEP |
949 | &autosleep_attr.attr, |
950 | #endif |
951 | #ifdef CONFIG_PM_WAKELOCKS |
952 | &wake_lock_attr.attr, |
953 | &wake_unlock_attr.attr, |
954 | #endif |
955 | #ifdef CONFIG_PM_SLEEP_DEBUG |
956 | &pm_test_attr.attr, |
957 | &pm_print_times_attr.attr, |
958 | &pm_wakeup_irq_attr.attr, |
959 | &pm_debug_messages_attr.attr, |
960 | #endif |
961 | #endif |
962 | #ifdef CONFIG_FREEZER |
963 | &pm_freeze_timeout_attr.attr, |
964 | #endif |
965 | NULL, |
966 | }; |
967 | |
968 | static const struct attribute_group attr_group = { |
969 | .attrs = g, |
970 | }; |
971 | |
972 | static const struct attribute_group *attr_groups[] = { |
973 | &attr_group, |
974 | #ifdef CONFIG_PM_SLEEP |
975 | &suspend_attr_group, |
976 | #endif |
977 | NULL, |
978 | }; |
979 | |
980 | struct workqueue_struct *pm_wq; |
981 | EXPORT_SYMBOL_GPL(pm_wq); |
982 | |
983 | static int __init pm_start_workqueue(void) |
984 | { |
985 | pm_wq = alloc_workqueue(fmt: "pm" , flags: WQ_FREEZABLE, max_active: 0); |
986 | |
987 | return pm_wq ? 0 : -ENOMEM; |
988 | } |
989 | |
990 | static int __init pm_init(void) |
991 | { |
992 | int error = pm_start_workqueue(); |
993 | if (error) |
994 | return error; |
995 | hibernate_image_size_init(); |
996 | hibernate_reserved_size_init(); |
997 | pm_states_init(); |
998 | power_kobj = kobject_create_and_add(name: "power" , NULL); |
999 | if (!power_kobj) |
1000 | return -ENOMEM; |
1001 | error = sysfs_create_groups(kobj: power_kobj, groups: attr_groups); |
1002 | if (error) |
1003 | return error; |
1004 | pm_print_times_init(); |
1005 | return pm_autosleep_init(); |
1006 | } |
1007 | |
1008 | core_initcall(pm_init); |
1009 | |