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17
18#define pr_fmt(fmt) "PM: " fmt
19
20#include <linux/device.h>
21#include <linux/export.h>
22#include <linux/mutex.h>
23#include <linux/pm.h>
24#include <linux/pm_runtime.h>
25#include <linux/pm-trace.h>
26#include <linux/pm_wakeirq.h>
27#include <linux/interrupt.h>
28#include <linux/sched.h>
29#include <linux/sched/debug.h>
30#include <linux/async.h>
31#include <linux/suspend.h>
32#include <trace/events/power.h>
33#include <linux/cpufreq.h>
34#include <linux/cpuidle.h>
35#include <linux/devfreq.h>
36#include <linux/timer.h>
37
38#include "../base.h"
39#include "power.h"
40
41typedef int (*pm_callback_t)(struct device *);
42
43
44
45
46
47
48
49
50
51
52
53LIST_HEAD(dpm_list);
54static LIST_HEAD(dpm_prepared_list);
55static LIST_HEAD(dpm_suspended_list);
56static LIST_HEAD(dpm_late_early_list);
57static LIST_HEAD(dpm_noirq_list);
58
59struct suspend_stats suspend_stats;
60static DEFINE_MUTEX(dpm_list_mtx);
61static pm_message_t pm_transition;
62
63static int async_error;
64
65static const char *pm_verb(int event)
66{
67 switch (event) {
68 case PM_EVENT_SUSPEND:
69 return "suspend";
70 case PM_EVENT_RESUME:
71 return "resume";
72 case PM_EVENT_FREEZE:
73 return "freeze";
74 case PM_EVENT_QUIESCE:
75 return "quiesce";
76 case PM_EVENT_HIBERNATE:
77 return "hibernate";
78 case PM_EVENT_THAW:
79 return "thaw";
80 case PM_EVENT_RESTORE:
81 return "restore";
82 case PM_EVENT_RECOVER:
83 return "recover";
84 default:
85 return "(unknown PM event)";
86 }
87}
88
89
90
91
92
93void device_pm_sleep_init(struct device *dev)
94{
95 dev->power.is_prepared = false;
96 dev->power.is_suspended = false;
97 dev->power.is_noirq_suspended = false;
98 dev->power.is_late_suspended = false;
99 init_completion(&dev->power.completion);
100 complete_all(&dev->power.completion);
101 dev->power.wakeup = NULL;
102 INIT_LIST_HEAD(&dev->power.entry);
103}
104
105
106
107
108void device_pm_lock(void)
109{
110 mutex_lock(&dpm_list_mtx);
111}
112
113
114
115
116void device_pm_unlock(void)
117{
118 mutex_unlock(&dpm_list_mtx);
119}
120
121
122
123
124
125void device_pm_add(struct device *dev)
126{
127
128 if (device_pm_not_required(dev))
129 return;
130
131 pr_debug("Adding info for %s:%s\n",
132 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
133 device_pm_check_callbacks(dev);
134 mutex_lock(&dpm_list_mtx);
135 if (dev->parent && dev->parent->power.is_prepared)
136 dev_warn(dev, "parent %s should not be sleeping\n",
137 dev_name(dev->parent));
138 list_add_tail(&dev->power.entry, &dpm_list);
139 dev->power.in_dpm_list = true;
140 mutex_unlock(&dpm_list_mtx);
141}
142
143
144
145
146
147void device_pm_remove(struct device *dev)
148{
149 if (device_pm_not_required(dev))
150 return;
151
152 pr_debug("Removing info for %s:%s\n",
153 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
154 complete_all(&dev->power.completion);
155 mutex_lock(&dpm_list_mtx);
156 list_del_init(&dev->power.entry);
157 dev->power.in_dpm_list = false;
158 mutex_unlock(&dpm_list_mtx);
159 device_wakeup_disable(dev);
160 pm_runtime_remove(dev);
161 device_pm_check_callbacks(dev);
162}
163
164
165
166
167
168
169void device_pm_move_before(struct device *deva, struct device *devb)
170{
171 pr_debug("Moving %s:%s before %s:%s\n",
172 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
173 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
174
175 list_move_tail(&deva->power.entry, &devb->power.entry);
176}
177
178
179
180
181
182
183void device_pm_move_after(struct device *deva, struct device *devb)
184{
185 pr_debug("Moving %s:%s after %s:%s\n",
186 deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
187 devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
188
189 list_move(&deva->power.entry, &devb->power.entry);
190}
191
192
193
194
195
196void device_pm_move_last(struct device *dev)
197{
198 pr_debug("Moving %s:%s to end of list\n",
199 dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
200 list_move_tail(&dev->power.entry, &dpm_list);
201}
202
203static ktime_t initcall_debug_start(struct device *dev, void *cb)
204{
205 if (!pm_print_times_enabled)
206 return 0;
207
208 dev_info(dev, "calling %pS @ %i, parent: %s\n", cb,
209 task_pid_nr(current),
210 dev->parent ? dev_name(dev->parent) : "none");
211 return ktime_get();
212}
213
214static void initcall_debug_report(struct device *dev, ktime_t calltime,
215 void *cb, int error)
216{
217 ktime_t rettime;
218 s64 nsecs;
219
220 if (!pm_print_times_enabled)
221 return;
222
223 rettime = ktime_get();
224 nsecs = (s64) ktime_to_ns(ktime_sub(rettime, calltime));
225
226 dev_info(dev, "%pS returned %d after %Ld usecs\n", cb, error,
227 (unsigned long long)nsecs >> 10);
228}
229
230
231
232
233
234
235static void dpm_wait(struct device *dev, bool async)
236{
237 if (!dev)
238 return;
239
240 if (async || (pm_async_enabled && dev->power.async_suspend))
241 wait_for_completion(&dev->power.completion);
242}
243
244static int dpm_wait_fn(struct device *dev, void *async_ptr)
245{
246 dpm_wait(dev, *((bool *)async_ptr));
247 return 0;
248}
249
250static void dpm_wait_for_children(struct device *dev, bool async)
251{
252 device_for_each_child(dev, &async, dpm_wait_fn);
253}
254
255static void dpm_wait_for_suppliers(struct device *dev, bool async)
256{
257 struct device_link *link;
258 int idx;
259
260 idx = device_links_read_lock();
261
262
263
264
265
266
267
268
269 list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
270 if (READ_ONCE(link->status) != DL_STATE_DORMANT)
271 dpm_wait(link->supplier, async);
272
273 device_links_read_unlock(idx);
274}
275
276static void dpm_wait_for_superior(struct device *dev, bool async)
277{
278 dpm_wait(dev->parent, async);
279 dpm_wait_for_suppliers(dev, async);
280}
281
282static void dpm_wait_for_consumers(struct device *dev, bool async)
283{
284 struct device_link *link;
285 int idx;
286
287 idx = device_links_read_lock();
288
289
290
291
292
293
294
295
296
297
298 list_for_each_entry_rcu(link, &dev->links.consumers, s_node)
299 if (READ_ONCE(link->status) != DL_STATE_DORMANT)
300 dpm_wait(link->consumer, async);
301
302 device_links_read_unlock(idx);
303}
304
305static void dpm_wait_for_subordinate(struct device *dev, bool async)
306{
307 dpm_wait_for_children(dev, async);
308 dpm_wait_for_consumers(dev, async);
309}
310
311
312
313
314
315
316static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state)
317{
318 switch (state.event) {
319#ifdef CONFIG_SUSPEND
320 case PM_EVENT_SUSPEND:
321 return ops->suspend;
322 case PM_EVENT_RESUME:
323 return ops->resume;
324#endif
325#ifdef CONFIG_HIBERNATE_CALLBACKS
326 case PM_EVENT_FREEZE:
327 case PM_EVENT_QUIESCE:
328 return ops->freeze;
329 case PM_EVENT_HIBERNATE:
330 return ops->poweroff;
331 case PM_EVENT_THAW:
332 case PM_EVENT_RECOVER:
333 return ops->thaw;
334 break;
335 case PM_EVENT_RESTORE:
336 return ops->restore;
337#endif
338 }
339
340 return NULL;
341}
342
343
344
345
346
347
348
349
350static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops,
351 pm_message_t state)
352{
353 switch (state.event) {
354#ifdef CONFIG_SUSPEND
355 case PM_EVENT_SUSPEND:
356 return ops->suspend_late;
357 case PM_EVENT_RESUME:
358 return ops->resume_early;
359#endif
360#ifdef CONFIG_HIBERNATE_CALLBACKS
361 case PM_EVENT_FREEZE:
362 case PM_EVENT_QUIESCE:
363 return ops->freeze_late;
364 case PM_EVENT_HIBERNATE:
365 return ops->poweroff_late;
366 case PM_EVENT_THAW:
367 case PM_EVENT_RECOVER:
368 return ops->thaw_early;
369 case PM_EVENT_RESTORE:
370 return ops->restore_early;
371#endif
372 }
373
374 return NULL;
375}
376
377
378
379
380
381
382
383
384
385static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state)
386{
387 switch (state.event) {
388#ifdef CONFIG_SUSPEND
389 case PM_EVENT_SUSPEND:
390 return ops->suspend_noirq;
391 case PM_EVENT_RESUME:
392 return ops->resume_noirq;
393#endif
394#ifdef CONFIG_HIBERNATE_CALLBACKS
395 case PM_EVENT_FREEZE:
396 case PM_EVENT_QUIESCE:
397 return ops->freeze_noirq;
398 case PM_EVENT_HIBERNATE:
399 return ops->poweroff_noirq;
400 case PM_EVENT_THAW:
401 case PM_EVENT_RECOVER:
402 return ops->thaw_noirq;
403 case PM_EVENT_RESTORE:
404 return ops->restore_noirq;
405#endif
406 }
407
408 return NULL;
409}
410
411static void pm_dev_dbg(struct device *dev, pm_message_t state, const char *info)
412{
413 dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event),
414 ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
415 ", may wakeup" : "");
416}
417
418static void pm_dev_err(struct device *dev, pm_message_t state, const char *info,
419 int error)
420{
421 pr_err("Device %s failed to %s%s: error %d\n",
422 dev_name(dev), pm_verb(state.event), info, error);
423}
424
425static void dpm_show_time(ktime_t starttime, pm_message_t state, int error,
426 const char *info)
427{
428 ktime_t calltime;
429 u64 usecs64;
430 int usecs;
431
432 calltime = ktime_get();
433 usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));
434 do_div(usecs64, NSEC_PER_USEC);
435 usecs = usecs64;
436 if (usecs == 0)
437 usecs = 1;
438
439 pm_pr_dbg("%s%s%s of devices %s after %ld.%03ld msecs\n",
440 info ?: "", info ? " " : "", pm_verb(state.event),
441 error ? "aborted" : "complete",
442 usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);
443}
444
445static int dpm_run_callback(pm_callback_t cb, struct device *dev,
446 pm_message_t state, const char *info)
447{
448 ktime_t calltime;
449 int error;
450
451 if (!cb)
452 return 0;
453
454 calltime = initcall_debug_start(dev, cb);
455
456 pm_dev_dbg(dev, state, info);
457 trace_device_pm_callback_start(dev, info, state.event);
458 error = cb(dev);
459 trace_device_pm_callback_end(dev, error);
460 suspend_report_result(cb, error);
461
462 initcall_debug_report(dev, calltime, cb, error);
463
464 return error;
465}
466
467#ifdef CONFIG_DPM_WATCHDOG
468struct dpm_watchdog {
469 struct device *dev;
470 struct task_struct *tsk;
471 struct timer_list timer;
472};
473
474#define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \
475 struct dpm_watchdog wd
476
477
478
479
480
481
482
483
484
485static void dpm_watchdog_handler(struct timer_list *t)
486{
487 struct dpm_watchdog *wd = from_timer(wd, t, timer);
488
489 dev_emerg(wd->dev, "**** DPM device timeout ****\n");
490 show_stack(wd->tsk, NULL);
491 panic("%s %s: unrecoverable failure\n",
492 dev_driver_string(wd->dev), dev_name(wd->dev));
493}
494
495
496
497
498
499
500static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev)
501{
502 struct timer_list *timer = &wd->timer;
503
504 wd->dev = dev;
505 wd->tsk = current;
506
507 timer_setup_on_stack(timer, dpm_watchdog_handler, 0);
508
509 timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT;
510 add_timer(timer);
511}
512
513
514
515
516
517static void dpm_watchdog_clear(struct dpm_watchdog *wd)
518{
519 struct timer_list *timer = &wd->timer;
520
521 del_timer_sync(timer);
522 destroy_timer_on_stack(timer);
523}
524#else
525#define DECLARE_DPM_WATCHDOG_ON_STACK(wd)
526#define dpm_watchdog_set(x, y)
527#define dpm_watchdog_clear(x)
528#endif
529
530
531
532
533
534
535
536static pm_message_t suspend_event(pm_message_t resume_msg)
537{
538 switch (resume_msg.event) {
539 case PM_EVENT_RESUME:
540 return PMSG_SUSPEND;
541 case PM_EVENT_THAW:
542 case PM_EVENT_RESTORE:
543 return PMSG_FREEZE;
544 case PM_EVENT_RECOVER:
545 return PMSG_HIBERNATE;
546 }
547 return PMSG_ON;
548}
549
550
551
552
553
554
555
556
557bool dev_pm_may_skip_resume(struct device *dev)
558{
559 return !dev->power.must_resume && pm_transition.event != PM_EVENT_RESTORE;
560}
561
562static pm_callback_t dpm_subsys_resume_noirq_cb(struct device *dev,
563 pm_message_t state,
564 const char **info_p)
565{
566 pm_callback_t callback;
567 const char *info;
568
569 if (dev->pm_domain) {
570 info = "noirq power domain ";
571 callback = pm_noirq_op(&dev->pm_domain->ops, state);
572 } else if (dev->type && dev->type->pm) {
573 info = "noirq type ";
574 callback = pm_noirq_op(dev->type->pm, state);
575 } else if (dev->class && dev->class->pm) {
576 info = "noirq class ";
577 callback = pm_noirq_op(dev->class->pm, state);
578 } else if (dev->bus && dev->bus->pm) {
579 info = "noirq bus ";
580 callback = pm_noirq_op(dev->bus->pm, state);
581 } else {
582 return NULL;
583 }
584
585 if (info_p)
586 *info_p = info;
587
588 return callback;
589}
590
591static pm_callback_t dpm_subsys_suspend_noirq_cb(struct device *dev,
592 pm_message_t state,
593 const char **info_p);
594
595static pm_callback_t dpm_subsys_suspend_late_cb(struct device *dev,
596 pm_message_t state,
597 const char **info_p);
598
599
600
601
602
603
604
605
606
607
608static int device_resume_noirq(struct device *dev, pm_message_t state, bool async)
609{
610 pm_callback_t callback;
611 const char *info;
612 bool skip_resume;
613 int error = 0;
614
615 TRACE_DEVICE(dev);
616 TRACE_RESUME(0);
617
618 if (dev->power.syscore || dev->power.direct_complete)
619 goto Out;
620
621 if (!dev->power.is_noirq_suspended)
622 goto Out;
623
624 dpm_wait_for_superior(dev, async);
625
626 skip_resume = dev_pm_may_skip_resume(dev);
627
628 callback = dpm_subsys_resume_noirq_cb(dev, state, &info);
629 if (callback)
630 goto Run;
631
632 if (skip_resume)
633 goto Skip;
634
635 if (dev_pm_smart_suspend_and_suspended(dev)) {
636 pm_message_t suspend_msg = suspend_event(state);
637
638
639
640
641
642
643
644
645
646 if (!dpm_subsys_suspend_late_cb(dev, suspend_msg, NULL) &&
647 !dpm_subsys_suspend_noirq_cb(dev, suspend_msg, NULL)) {
648 if (state.event == PM_EVENT_THAW) {
649 skip_resume = true;
650 goto Skip;
651 } else {
652 pm_runtime_set_active(dev);
653 }
654 }
655 }
656
657 if (dev->driver && dev->driver->pm) {
658 info = "noirq driver ";
659 callback = pm_noirq_op(dev->driver->pm, state);
660 }
661
662Run:
663 error = dpm_run_callback(callback, dev, state, info);
664
665Skip:
666 dev->power.is_noirq_suspended = false;
667
668 if (skip_resume) {
669
670 dev->power.is_late_suspended = false;
671 dev->power.is_suspended = false;
672
673
674
675
676
677
678
679 pm_runtime_set_suspended(dev);
680 }
681
682Out:
683 complete_all(&dev->power.completion);
684 TRACE_RESUME(error);
685 return error;
686}
687
688static bool is_async(struct device *dev)
689{
690 return dev->power.async_suspend && pm_async_enabled
691 && !pm_trace_is_enabled();
692}
693
694static bool dpm_async_fn(struct device *dev, async_func_t func)
695{
696 reinit_completion(&dev->power.completion);
697
698 if (is_async(dev)) {
699 get_device(dev);
700 async_schedule(func, dev);
701 return true;
702 }
703
704 return false;
705}
706
707static void async_resume_noirq(void *data, async_cookie_t cookie)
708{
709 struct device *dev = (struct device *)data;
710 int error;
711
712 error = device_resume_noirq(dev, pm_transition, true);
713 if (error)
714 pm_dev_err(dev, pm_transition, " async", error);
715
716 put_device(dev);
717}
718
719void dpm_noirq_resume_devices(pm_message_t state)
720{
721 struct device *dev;
722 ktime_t starttime = ktime_get();
723
724 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true);
725 mutex_lock(&dpm_list_mtx);
726 pm_transition = state;
727
728
729
730
731
732
733 list_for_each_entry(dev, &dpm_noirq_list, power.entry)
734 dpm_async_fn(dev, async_resume_noirq);
735
736 while (!list_empty(&dpm_noirq_list)) {
737 dev = to_device(dpm_noirq_list.next);
738 get_device(dev);
739 list_move_tail(&dev->power.entry, &dpm_late_early_list);
740 mutex_unlock(&dpm_list_mtx);
741
742 if (!is_async(dev)) {
743 int error;
744
745 error = device_resume_noirq(dev, state, false);
746 if (error) {
747 suspend_stats.failed_resume_noirq++;
748 dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
749 dpm_save_failed_dev(dev_name(dev));
750 pm_dev_err(dev, state, " noirq", error);
751 }
752 }
753
754 mutex_lock(&dpm_list_mtx);
755 put_device(dev);
756 }
757 mutex_unlock(&dpm_list_mtx);
758 async_synchronize_full();
759 dpm_show_time(starttime, state, 0, "noirq");
760 trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false);
761}
762
763void dpm_noirq_end(void)
764{
765 resume_device_irqs();
766 device_wakeup_disarm_wake_irqs();
767 cpuidle_resume();
768}
769
770
771
772
773
774
775
776
777void dpm_resume_noirq(pm_message_t state)
778{
779 dpm_noirq_resume_devices(state);
780 dpm_noirq_end();
781}
782
783static pm_callback_t dpm_subsys_resume_early_cb(struct device *dev,
784 pm_message_t state,
785 const char **info_p)
786{
787 pm_callback_t callback;
788 const char *info;
789
790 if (dev->pm_domain) {
791 info = "early power domain ";
792 callback = pm_late_early_op(&dev->pm_domain->ops, state);
793 } else if (dev->type && dev->type->pm) {
794 info = "early type ";
795 callback = pm_late_early_op(dev->type->pm, state);
796 } else if (dev->class && dev->class->pm) {
797 info = "early class ";
798 callback = pm_late_early_op(dev->class->pm, state);
799 } else if (dev->bus && dev->bus->pm) {
800 info = "early bus ";
801 callback = pm_late_early_op(dev->bus->pm, state);
802 } else {
803 return NULL;
804 }
805
806 if (info_p)
807 *info_p = info;
808
809 return callback;
810}
811
812
813
814
815
816
817
818
819
820static int device_resume_early(struct device *dev, pm_message_t state, bool async)
821{
822 pm_callback_t callback;
823 const char *info;
824 int error = 0;
825
826 TRACE_DEVICE(dev);
827 TRACE_RESUME(0);
828
829 if (dev->power.syscore || dev->power.direct_complete)
830 goto Out;
831
832 if (!dev->power.is_late_suspended)
833 goto Out;
834
835 dpm_wait_for_superior(dev, async);
836
837 callback = dpm_subsys_resume_early_cb(dev, state, &info);
838
839 if (!callback && dev->driver && dev->driver->pm) {
840 info = "early driver ";
841 callback = pm_late_early_op(dev->driver->pm, state);
842 }
843
844 error = dpm_run_callback(callback, dev, state, info);
845 dev->power.is_late_suspended = false;
846
847 Out:
848 TRACE_RESUME(error);
849
850 pm_runtime_enable(dev);
851 complete_all(&dev->power.completion);
852 return error;
853}
854
855static void async_resume_early(void *data, async_cookie_t cookie)
856{
857 struct device *dev = (struct device *)data;
858 int error;
859
860 error = device_resume_early(dev, pm_transition, true);
861 if (error)
862 pm_dev_err(dev, pm_transition, " async", error);
863
864 put_device(dev);
865}
866
867
868
869
870
871void dpm_resume_early(pm_message_t state)
872{
873 struct device *dev;
874 ktime_t starttime = ktime_get();
875
876 trace_suspend_resume(TPS("dpm_resume_early"), state.event, true);
877 mutex_lock(&dpm_list_mtx);
878 pm_transition = state;
879
880
881
882
883
884
885 list_for_each_entry(dev, &dpm_late_early_list, power.entry)
886 dpm_async_fn(dev, async_resume_early);
887
888 while (!list_empty(&dpm_late_early_list)) {
889 dev = to_device(dpm_late_early_list.next);
890 get_device(dev);
891 list_move_tail(&dev->power.entry, &dpm_suspended_list);
892 mutex_unlock(&dpm_list_mtx);
893
894 if (!is_async(dev)) {
895 int error;
896
897 error = device_resume_early(dev, state, false);
898 if (error) {
899 suspend_stats.failed_resume_early++;
900 dpm_save_failed_step(SUSPEND_RESUME_EARLY);
901 dpm_save_failed_dev(dev_name(dev));
902 pm_dev_err(dev, state, " early", error);
903 }
904 }
905 mutex_lock(&dpm_list_mtx);
906 put_device(dev);
907 }
908 mutex_unlock(&dpm_list_mtx);
909 async_synchronize_full();
910 dpm_show_time(starttime, state, 0, "early");
911 trace_suspend_resume(TPS("dpm_resume_early"), state.event, false);
912}
913
914
915
916
917
918void dpm_resume_start(pm_message_t state)
919{
920 dpm_resume_noirq(state);
921 dpm_resume_early(state);
922}
923EXPORT_SYMBOL_GPL(dpm_resume_start);
924
925
926
927
928
929
930
931static int device_resume(struct device *dev, pm_message_t state, bool async)
932{
933 pm_callback_t callback = NULL;
934 const char *info = NULL;
935 int error = 0;
936 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
937
938 TRACE_DEVICE(dev);
939 TRACE_RESUME(0);
940
941 if (dev->power.syscore)
942 goto Complete;
943
944 if (dev->power.direct_complete) {
945
946 pm_runtime_enable(dev);
947 goto Complete;
948 }
949
950 dpm_wait_for_superior(dev, async);
951 dpm_watchdog_set(&wd, dev);
952 device_lock(dev);
953
954
955
956
957
958 dev->power.is_prepared = false;
959
960 if (!dev->power.is_suspended)
961 goto Unlock;
962
963 if (dev->pm_domain) {
964 info = "power domain ";
965 callback = pm_op(&dev->pm_domain->ops, state);
966 goto Driver;
967 }
968
969 if (dev->type && dev->type->pm) {
970 info = "type ";
971 callback = pm_op(dev->type->pm, state);
972 goto Driver;
973 }
974
975 if (dev->class && dev->class->pm) {
976 info = "class ";
977 callback = pm_op(dev->class->pm, state);
978 goto Driver;
979 }
980
981 if (dev->bus) {
982 if (dev->bus->pm) {
983 info = "bus ";
984 callback = pm_op(dev->bus->pm, state);
985 } else if (dev->bus->resume) {
986 info = "legacy bus ";
987 callback = dev->bus->resume;
988 goto End;
989 }
990 }
991
992 Driver:
993 if (!callback && dev->driver && dev->driver->pm) {
994 info = "driver ";
995 callback = pm_op(dev->driver->pm, state);
996 }
997
998 End:
999 error = dpm_run_callback(callback, dev, state, info);
1000 dev->power.is_suspended = false;
1001
1002 Unlock:
1003 device_unlock(dev);
1004 dpm_watchdog_clear(&wd);
1005
1006 Complete:
1007 complete_all(&dev->power.completion);
1008
1009 TRACE_RESUME(error);
1010
1011 return error;
1012}
1013
1014static void async_resume(void *data, async_cookie_t cookie)
1015{
1016 struct device *dev = (struct device *)data;
1017 int error;
1018
1019 error = device_resume(dev, pm_transition, true);
1020 if (error)
1021 pm_dev_err(dev, pm_transition, " async", error);
1022 put_device(dev);
1023}
1024
1025
1026
1027
1028
1029
1030
1031
1032void dpm_resume(pm_message_t state)
1033{
1034 struct device *dev;
1035 ktime_t starttime = ktime_get();
1036
1037 trace_suspend_resume(TPS("dpm_resume"), state.event, true);
1038 might_sleep();
1039
1040 mutex_lock(&dpm_list_mtx);
1041 pm_transition = state;
1042 async_error = 0;
1043
1044 list_for_each_entry(dev, &dpm_suspended_list, power.entry)
1045 dpm_async_fn(dev, async_resume);
1046
1047 while (!list_empty(&dpm_suspended_list)) {
1048 dev = to_device(dpm_suspended_list.next);
1049 get_device(dev);
1050 if (!is_async(dev)) {
1051 int error;
1052
1053 mutex_unlock(&dpm_list_mtx);
1054
1055 error = device_resume(dev, state, false);
1056 if (error) {
1057 suspend_stats.failed_resume++;
1058 dpm_save_failed_step(SUSPEND_RESUME);
1059 dpm_save_failed_dev(dev_name(dev));
1060 pm_dev_err(dev, state, "", error);
1061 }
1062
1063 mutex_lock(&dpm_list_mtx);
1064 }
1065 if (!list_empty(&dev->power.entry))
1066 list_move_tail(&dev->power.entry, &dpm_prepared_list);
1067 put_device(dev);
1068 }
1069 mutex_unlock(&dpm_list_mtx);
1070 async_synchronize_full();
1071 dpm_show_time(starttime, state, 0, NULL);
1072
1073 cpufreq_resume();
1074 devfreq_resume();
1075 trace_suspend_resume(TPS("dpm_resume"), state.event, false);
1076}
1077
1078
1079
1080
1081
1082
1083static void device_complete(struct device *dev, pm_message_t state)
1084{
1085 void (*callback)(struct device *) = NULL;
1086 const char *info = NULL;
1087
1088 if (dev->power.syscore)
1089 return;
1090
1091 device_lock(dev);
1092
1093 if (dev->pm_domain) {
1094 info = "completing power domain ";
1095 callback = dev->pm_domain->ops.complete;
1096 } else if (dev->type && dev->type->pm) {
1097 info = "completing type ";
1098 callback = dev->type->pm->complete;
1099 } else if (dev->class && dev->class->pm) {
1100 info = "completing class ";
1101 callback = dev->class->pm->complete;
1102 } else if (dev->bus && dev->bus->pm) {
1103 info = "completing bus ";
1104 callback = dev->bus->pm->complete;
1105 }
1106
1107 if (!callback && dev->driver && dev->driver->pm) {
1108 info = "completing driver ";
1109 callback = dev->driver->pm->complete;
1110 }
1111
1112 if (callback) {
1113 pm_dev_dbg(dev, state, info);
1114 callback(dev);
1115 }
1116
1117 device_unlock(dev);
1118
1119 pm_runtime_put(dev);
1120}
1121
1122
1123
1124
1125
1126
1127
1128
1129void dpm_complete(pm_message_t state)
1130{
1131 struct list_head list;
1132
1133 trace_suspend_resume(TPS("dpm_complete"), state.event, true);
1134 might_sleep();
1135
1136 INIT_LIST_HEAD(&list);
1137 mutex_lock(&dpm_list_mtx);
1138 while (!list_empty(&dpm_prepared_list)) {
1139 struct device *dev = to_device(dpm_prepared_list.prev);
1140
1141 get_device(dev);
1142 dev->power.is_prepared = false;
1143 list_move(&dev->power.entry, &list);
1144 mutex_unlock(&dpm_list_mtx);
1145
1146 trace_device_pm_callback_start(dev, "", state.event);
1147 device_complete(dev, state);
1148 trace_device_pm_callback_end(dev, 0);
1149
1150 mutex_lock(&dpm_list_mtx);
1151 put_device(dev);
1152 }
1153 list_splice(&list, &dpm_list);
1154 mutex_unlock(&dpm_list_mtx);
1155
1156
1157 device_unblock_probing();
1158 trace_suspend_resume(TPS("dpm_complete"), state.event, false);
1159}
1160
1161
1162
1163
1164
1165
1166
1167
1168void dpm_resume_end(pm_message_t state)
1169{
1170 dpm_resume(state);
1171 dpm_complete(state);
1172}
1173EXPORT_SYMBOL_GPL(dpm_resume_end);
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185static pm_message_t resume_event(pm_message_t sleep_state)
1186{
1187 switch (sleep_state.event) {
1188 case PM_EVENT_SUSPEND:
1189 return PMSG_RESUME;
1190 case PM_EVENT_FREEZE:
1191 case PM_EVENT_QUIESCE:
1192 return PMSG_RECOVER;
1193 case PM_EVENT_HIBERNATE:
1194 return PMSG_RESTORE;
1195 }
1196 return PMSG_ON;
1197}
1198
1199static void dpm_superior_set_must_resume(struct device *dev)
1200{
1201 struct device_link *link;
1202 int idx;
1203
1204 if (dev->parent)
1205 dev->parent->power.must_resume = true;
1206
1207 idx = device_links_read_lock();
1208
1209 list_for_each_entry_rcu(link, &dev->links.suppliers, c_node)
1210 link->supplier->power.must_resume = true;
1211
1212 device_links_read_unlock(idx);
1213}
1214
1215static pm_callback_t dpm_subsys_suspend_noirq_cb(struct device *dev,
1216 pm_message_t state,
1217 const char **info_p)
1218{
1219 pm_callback_t callback;
1220 const char *info;
1221
1222 if (dev->pm_domain) {
1223 info = "noirq power domain ";
1224 callback = pm_noirq_op(&dev->pm_domain->ops, state);
1225 } else if (dev->type && dev->type->pm) {
1226 info = "noirq type ";
1227 callback = pm_noirq_op(dev->type->pm, state);
1228 } else if (dev->class && dev->class->pm) {
1229 info = "noirq class ";
1230 callback = pm_noirq_op(dev->class->pm, state);
1231 } else if (dev->bus && dev->bus->pm) {
1232 info = "noirq bus ";
1233 callback = pm_noirq_op(dev->bus->pm, state);
1234 } else {
1235 return NULL;
1236 }
1237
1238 if (info_p)
1239 *info_p = info;
1240
1241 return callback;
1242}
1243
1244static bool device_must_resume(struct device *dev, pm_message_t state,
1245 bool no_subsys_suspend_noirq)
1246{
1247 pm_message_t resume_msg = resume_event(state);
1248
1249
1250
1251
1252
1253
1254
1255 if (no_subsys_suspend_noirq &&
1256 !dpm_subsys_suspend_late_cb(dev, state, NULL) &&
1257 !dpm_subsys_resume_early_cb(dev, resume_msg, NULL) &&
1258 !dpm_subsys_resume_noirq_cb(dev, resume_msg, NULL))
1259 return !pm_runtime_status_suspended(dev) &&
1260 (resume_msg.event != PM_EVENT_RESUME ||
1261 (device_can_wakeup(dev) && !device_may_wakeup(dev)));
1262
1263
1264
1265
1266
1267 return !dev->power.may_skip_resume;
1268}
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool async)
1280{
1281 pm_callback_t callback;
1282 const char *info;
1283 bool no_subsys_cb = false;
1284 int error = 0;
1285
1286 TRACE_DEVICE(dev);
1287 TRACE_SUSPEND(0);
1288
1289 dpm_wait_for_subordinate(dev, async);
1290
1291 if (async_error)
1292 goto Complete;
1293
1294 if (pm_wakeup_pending()) {
1295 async_error = -EBUSY;
1296 goto Complete;
1297 }
1298
1299 if (dev->power.syscore || dev->power.direct_complete)
1300 goto Complete;
1301
1302 callback = dpm_subsys_suspend_noirq_cb(dev, state, &info);
1303 if (callback)
1304 goto Run;
1305
1306 no_subsys_cb = !dpm_subsys_suspend_late_cb(dev, state, NULL);
1307
1308 if (dev_pm_smart_suspend_and_suspended(dev) && no_subsys_cb)
1309 goto Skip;
1310
1311 if (dev->driver && dev->driver->pm) {
1312 info = "noirq driver ";
1313 callback = pm_noirq_op(dev->driver->pm, state);
1314 }
1315
1316Run:
1317 error = dpm_run_callback(callback, dev, state, info);
1318 if (error) {
1319 async_error = error;
1320 goto Complete;
1321 }
1322
1323Skip:
1324 dev->power.is_noirq_suspended = true;
1325
1326 if (dev_pm_test_driver_flags(dev, DPM_FLAG_LEAVE_SUSPENDED)) {
1327 dev->power.must_resume = dev->power.must_resume ||
1328 atomic_read(&dev->power.usage_count) > 1 ||
1329 device_must_resume(dev, state, no_subsys_cb);
1330 } else {
1331 dev->power.must_resume = true;
1332 }
1333
1334 if (dev->power.must_resume)
1335 dpm_superior_set_must_resume(dev);
1336
1337Complete:
1338 complete_all(&dev->power.completion);
1339 TRACE_SUSPEND(error);
1340 return error;
1341}
1342
1343static void async_suspend_noirq(void *data, async_cookie_t cookie)
1344{
1345 struct device *dev = (struct device *)data;
1346 int error;
1347
1348 error = __device_suspend_noirq(dev, pm_transition, true);
1349 if (error) {
1350 dpm_save_failed_dev(dev_name(dev));
1351 pm_dev_err(dev, pm_transition, " async", error);
1352 }
1353
1354 put_device(dev);
1355}
1356
1357static int device_suspend_noirq(struct device *dev)
1358{
1359 if (dpm_async_fn(dev, async_suspend_noirq))
1360 return 0;
1361
1362 return __device_suspend_noirq(dev, pm_transition, false);
1363}
1364
1365void dpm_noirq_begin(void)
1366{
1367 cpuidle_pause();
1368 device_wakeup_arm_wake_irqs();
1369 suspend_device_irqs();
1370}
1371
1372int dpm_noirq_suspend_devices(pm_message_t state)
1373{
1374 ktime_t starttime = ktime_get();
1375 int error = 0;
1376
1377 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true);
1378 mutex_lock(&dpm_list_mtx);
1379 pm_transition = state;
1380 async_error = 0;
1381
1382 while (!list_empty(&dpm_late_early_list)) {
1383 struct device *dev = to_device(dpm_late_early_list.prev);
1384
1385 get_device(dev);
1386 mutex_unlock(&dpm_list_mtx);
1387
1388 error = device_suspend_noirq(dev);
1389
1390 mutex_lock(&dpm_list_mtx);
1391 if (error) {
1392 pm_dev_err(dev, state, " noirq", error);
1393 dpm_save_failed_dev(dev_name(dev));
1394 put_device(dev);
1395 break;
1396 }
1397 if (!list_empty(&dev->power.entry))
1398 list_move(&dev->power.entry, &dpm_noirq_list);
1399 put_device(dev);
1400
1401 if (async_error)
1402 break;
1403 }
1404 mutex_unlock(&dpm_list_mtx);
1405 async_synchronize_full();
1406 if (!error)
1407 error = async_error;
1408
1409 if (error) {
1410 suspend_stats.failed_suspend_noirq++;
1411 dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
1412 }
1413 dpm_show_time(starttime, state, error, "noirq");
1414 trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false);
1415 return error;
1416}
1417
1418
1419
1420
1421
1422
1423
1424
1425int dpm_suspend_noirq(pm_message_t state)
1426{
1427 int ret;
1428
1429 dpm_noirq_begin();
1430 ret = dpm_noirq_suspend_devices(state);
1431 if (ret)
1432 dpm_resume_noirq(resume_event(state));
1433
1434 return ret;
1435}
1436
1437static void dpm_propagate_wakeup_to_parent(struct device *dev)
1438{
1439 struct device *parent = dev->parent;
1440
1441 if (!parent)
1442 return;
1443
1444 spin_lock_irq(&parent->power.lock);
1445
1446 if (dev->power.wakeup_path && !parent->power.ignore_children)
1447 parent->power.wakeup_path = true;
1448
1449 spin_unlock_irq(&parent->power.lock);
1450}
1451
1452static pm_callback_t dpm_subsys_suspend_late_cb(struct device *dev,
1453 pm_message_t state,
1454 const char **info_p)
1455{
1456 pm_callback_t callback;
1457 const char *info;
1458
1459 if (dev->pm_domain) {
1460 info = "late power domain ";
1461 callback = pm_late_early_op(&dev->pm_domain->ops, state);
1462 } else if (dev->type && dev->type->pm) {
1463 info = "late type ";
1464 callback = pm_late_early_op(dev->type->pm, state);
1465 } else if (dev->class && dev->class->pm) {
1466 info = "late class ";
1467 callback = pm_late_early_op(dev->class->pm, state);
1468 } else if (dev->bus && dev->bus->pm) {
1469 info = "late bus ";
1470 callback = pm_late_early_op(dev->bus->pm, state);
1471 } else {
1472 return NULL;
1473 }
1474
1475 if (info_p)
1476 *info_p = info;
1477
1478 return callback;
1479}
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489static int __device_suspend_late(struct device *dev, pm_message_t state, bool async)
1490{
1491 pm_callback_t callback;
1492 const char *info;
1493 int error = 0;
1494
1495 TRACE_DEVICE(dev);
1496 TRACE_SUSPEND(0);
1497
1498 __pm_runtime_disable(dev, false);
1499
1500 dpm_wait_for_subordinate(dev, async);
1501
1502 if (async_error)
1503 goto Complete;
1504
1505 if (pm_wakeup_pending()) {
1506 async_error = -EBUSY;
1507 goto Complete;
1508 }
1509
1510 if (dev->power.syscore || dev->power.direct_complete)
1511 goto Complete;
1512
1513 callback = dpm_subsys_suspend_late_cb(dev, state, &info);
1514 if (callback)
1515 goto Run;
1516
1517 if (dev_pm_smart_suspend_and_suspended(dev) &&
1518 !dpm_subsys_suspend_noirq_cb(dev, state, NULL))
1519 goto Skip;
1520
1521 if (dev->driver && dev->driver->pm) {
1522 info = "late driver ";
1523 callback = pm_late_early_op(dev->driver->pm, state);
1524 }
1525
1526Run:
1527 error = dpm_run_callback(callback, dev, state, info);
1528 if (error) {
1529 async_error = error;
1530 goto Complete;
1531 }
1532 dpm_propagate_wakeup_to_parent(dev);
1533
1534Skip:
1535 dev->power.is_late_suspended = true;
1536
1537Complete:
1538 TRACE_SUSPEND(error);
1539 complete_all(&dev->power.completion);
1540 return error;
1541}
1542
1543static void async_suspend_late(void *data, async_cookie_t cookie)
1544{
1545 struct device *dev = (struct device *)data;
1546 int error;
1547
1548 error = __device_suspend_late(dev, pm_transition, true);
1549 if (error) {
1550 dpm_save_failed_dev(dev_name(dev));
1551 pm_dev_err(dev, pm_transition, " async", error);
1552 }
1553 put_device(dev);
1554}
1555
1556static int device_suspend_late(struct device *dev)
1557{
1558 if (dpm_async_fn(dev, async_suspend_late))
1559 return 0;
1560
1561 return __device_suspend_late(dev, pm_transition, false);
1562}
1563
1564
1565
1566
1567
1568int dpm_suspend_late(pm_message_t state)
1569{
1570 ktime_t starttime = ktime_get();
1571 int error = 0;
1572
1573 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true);
1574 mutex_lock(&dpm_list_mtx);
1575 pm_transition = state;
1576 async_error = 0;
1577
1578 while (!list_empty(&dpm_suspended_list)) {
1579 struct device *dev = to_device(dpm_suspended_list.prev);
1580
1581 get_device(dev);
1582 mutex_unlock(&dpm_list_mtx);
1583
1584 error = device_suspend_late(dev);
1585
1586 mutex_lock(&dpm_list_mtx);
1587 if (!list_empty(&dev->power.entry))
1588 list_move(&dev->power.entry, &dpm_late_early_list);
1589
1590 if (error) {
1591 pm_dev_err(dev, state, " late", error);
1592 dpm_save_failed_dev(dev_name(dev));
1593 put_device(dev);
1594 break;
1595 }
1596 put_device(dev);
1597
1598 if (async_error)
1599 break;
1600 }
1601 mutex_unlock(&dpm_list_mtx);
1602 async_synchronize_full();
1603 if (!error)
1604 error = async_error;
1605 if (error) {
1606 suspend_stats.failed_suspend_late++;
1607 dpm_save_failed_step(SUSPEND_SUSPEND_LATE);
1608 dpm_resume_early(resume_event(state));
1609 }
1610 dpm_show_time(starttime, state, error, "late");
1611 trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false);
1612 return error;
1613}
1614
1615
1616
1617
1618
1619int dpm_suspend_end(pm_message_t state)
1620{
1621 ktime_t starttime = ktime_get();
1622 int error;
1623
1624 error = dpm_suspend_late(state);
1625 if (error)
1626 goto out;
1627
1628 error = dpm_suspend_noirq(state);
1629 if (error)
1630 dpm_resume_early(resume_event(state));
1631
1632out:
1633 dpm_show_time(starttime, state, error, "end");
1634 return error;
1635}
1636EXPORT_SYMBOL_GPL(dpm_suspend_end);
1637
1638
1639
1640
1641
1642
1643
1644
1645static int legacy_suspend(struct device *dev, pm_message_t state,
1646 int (*cb)(struct device *dev, pm_message_t state),
1647 const char *info)
1648{
1649 int error;
1650 ktime_t calltime;
1651
1652 calltime = initcall_debug_start(dev, cb);
1653
1654 trace_device_pm_callback_start(dev, info, state.event);
1655 error = cb(dev, state);
1656 trace_device_pm_callback_end(dev, error);
1657 suspend_report_result(cb, error);
1658
1659 initcall_debug_report(dev, calltime, cb, error);
1660
1661 return error;
1662}
1663
1664static void dpm_clear_superiors_direct_complete(struct device *dev)
1665{
1666 struct device_link *link;
1667 int idx;
1668
1669 if (dev->parent) {
1670 spin_lock_irq(&dev->parent->power.lock);
1671 dev->parent->power.direct_complete = false;
1672 spin_unlock_irq(&dev->parent->power.lock);
1673 }
1674
1675 idx = device_links_read_lock();
1676
1677 list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) {
1678 spin_lock_irq(&link->supplier->power.lock);
1679 link->supplier->power.direct_complete = false;
1680 spin_unlock_irq(&link->supplier->power.lock);
1681 }
1682
1683 device_links_read_unlock(idx);
1684}
1685
1686
1687
1688
1689
1690
1691
1692static int __device_suspend(struct device *dev, pm_message_t state, bool async)
1693{
1694 pm_callback_t callback = NULL;
1695 const char *info = NULL;
1696 int error = 0;
1697 DECLARE_DPM_WATCHDOG_ON_STACK(wd);
1698
1699 TRACE_DEVICE(dev);
1700 TRACE_SUSPEND(0);
1701
1702 dpm_wait_for_subordinate(dev, async);
1703
1704 if (async_error) {
1705 dev->power.direct_complete = false;
1706 goto Complete;
1707 }
1708
1709
1710
1711
1712
1713
1714
1715 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
1716 pm_wakeup_event(dev, 0);
1717
1718 if (pm_wakeup_pending()) {
1719 dev->power.direct_complete = false;
1720 async_error = -EBUSY;
1721 goto Complete;
1722 }
1723
1724 if (dev->power.syscore)
1725 goto Complete;
1726
1727
1728 if (device_may_wakeup(dev) || dev->power.wakeup_path)
1729 dev->power.direct_complete = false;
1730
1731 if (dev->power.direct_complete) {
1732 if (pm_runtime_status_suspended(dev)) {
1733 pm_runtime_disable(dev);
1734 if (pm_runtime_status_suspended(dev)) {
1735 pm_dev_dbg(dev, state, "direct-complete ");
1736 goto Complete;
1737 }
1738
1739 pm_runtime_enable(dev);
1740 }
1741 dev->power.direct_complete = false;
1742 }
1743
1744 dev->power.may_skip_resume = false;
1745 dev->power.must_resume = false;
1746
1747 dpm_watchdog_set(&wd, dev);
1748 device_lock(dev);
1749
1750 if (dev->pm_domain) {
1751 info = "power domain ";
1752 callback = pm_op(&dev->pm_domain->ops, state);
1753 goto Run;
1754 }
1755
1756 if (dev->type && dev->type->pm) {
1757 info = "type ";
1758 callback = pm_op(dev->type->pm, state);
1759 goto Run;
1760 }
1761
1762 if (dev->class && dev->class->pm) {
1763 info = "class ";
1764 callback = pm_op(dev->class->pm, state);
1765 goto Run;
1766 }
1767
1768 if (dev->bus) {
1769 if (dev->bus->pm) {
1770 info = "bus ";
1771 callback = pm_op(dev->bus->pm, state);
1772 } else if (dev->bus->suspend) {
1773 pm_dev_dbg(dev, state, "legacy bus ");
1774 error = legacy_suspend(dev, state, dev->bus->suspend,
1775 "legacy bus ");
1776 goto End;
1777 }
1778 }
1779
1780 Run:
1781 if (!callback && dev->driver && dev->driver->pm) {
1782 info = "driver ";
1783 callback = pm_op(dev->driver->pm, state);
1784 }
1785
1786 error = dpm_run_callback(callback, dev, state, info);
1787
1788 End:
1789 if (!error) {
1790 dev->power.is_suspended = true;
1791 if (device_may_wakeup(dev))
1792 dev->power.wakeup_path = true;
1793
1794 dpm_propagate_wakeup_to_parent(dev);
1795 dpm_clear_superiors_direct_complete(dev);
1796 }
1797
1798 device_unlock(dev);
1799 dpm_watchdog_clear(&wd);
1800
1801 Complete:
1802 if (error)
1803 async_error = error;
1804
1805 complete_all(&dev->power.completion);
1806 TRACE_SUSPEND(error);
1807 return error;
1808}
1809
1810static void async_suspend(void *data, async_cookie_t cookie)
1811{
1812 struct device *dev = (struct device *)data;
1813 int error;
1814
1815 error = __device_suspend(dev, pm_transition, true);
1816 if (error) {
1817 dpm_save_failed_dev(dev_name(dev));
1818 pm_dev_err(dev, pm_transition, " async", error);
1819 }
1820
1821 put_device(dev);
1822}
1823
1824static int device_suspend(struct device *dev)
1825{
1826 if (dpm_async_fn(dev, async_suspend))
1827 return 0;
1828
1829 return __device_suspend(dev, pm_transition, false);
1830}
1831
1832
1833
1834
1835
1836int dpm_suspend(pm_message_t state)
1837{
1838 ktime_t starttime = ktime_get();
1839 int error = 0;
1840
1841 trace_suspend_resume(TPS("dpm_suspend"), state.event, true);
1842 might_sleep();
1843
1844 devfreq_suspend();
1845 cpufreq_suspend();
1846
1847 mutex_lock(&dpm_list_mtx);
1848 pm_transition = state;
1849 async_error = 0;
1850 while (!list_empty(&dpm_prepared_list)) {
1851 struct device *dev = to_device(dpm_prepared_list.prev);
1852
1853 get_device(dev);
1854 mutex_unlock(&dpm_list_mtx);
1855
1856 error = device_suspend(dev);
1857
1858 mutex_lock(&dpm_list_mtx);
1859 if (error) {
1860 pm_dev_err(dev, state, "", error);
1861 dpm_save_failed_dev(dev_name(dev));
1862 put_device(dev);
1863 break;
1864 }
1865 if (!list_empty(&dev->power.entry))
1866 list_move(&dev->power.entry, &dpm_suspended_list);
1867 put_device(dev);
1868 if (async_error)
1869 break;
1870 }
1871 mutex_unlock(&dpm_list_mtx);
1872 async_synchronize_full();
1873 if (!error)
1874 error = async_error;
1875 if (error) {
1876 suspend_stats.failed_suspend++;
1877 dpm_save_failed_step(SUSPEND_SUSPEND);
1878 }
1879 dpm_show_time(starttime, state, error, NULL);
1880 trace_suspend_resume(TPS("dpm_suspend"), state.event, false);
1881 return error;
1882}
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892static int device_prepare(struct device *dev, pm_message_t state)
1893{
1894 int (*callback)(struct device *) = NULL;
1895 int ret = 0;
1896
1897 if (dev->power.syscore)
1898 return 0;
1899
1900 WARN_ON(!pm_runtime_enabled(dev) &&
1901 dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND |
1902 DPM_FLAG_LEAVE_SUSPENDED));
1903
1904
1905
1906
1907
1908
1909
1910 pm_runtime_get_noresume(dev);
1911
1912 device_lock(dev);
1913
1914 dev->power.wakeup_path = false;
1915
1916 if (dev->power.no_pm_callbacks)
1917 goto unlock;
1918
1919 if (dev->pm_domain)
1920 callback = dev->pm_domain->ops.prepare;
1921 else if (dev->type && dev->type->pm)
1922 callback = dev->type->pm->prepare;
1923 else if (dev->class && dev->class->pm)
1924 callback = dev->class->pm->prepare;
1925 else if (dev->bus && dev->bus->pm)
1926 callback = dev->bus->pm->prepare;
1927
1928 if (!callback && dev->driver && dev->driver->pm)
1929 callback = dev->driver->pm->prepare;
1930
1931 if (callback)
1932 ret = callback(dev);
1933
1934unlock:
1935 device_unlock(dev);
1936
1937 if (ret < 0) {
1938 suspend_report_result(callback, ret);
1939 pm_runtime_put(dev);
1940 return ret;
1941 }
1942
1943
1944
1945
1946
1947
1948
1949 spin_lock_irq(&dev->power.lock);
1950 dev->power.direct_complete = state.event == PM_EVENT_SUSPEND &&
1951 ((pm_runtime_suspended(dev) && ret > 0) ||
1952 dev->power.no_pm_callbacks) &&
1953 !dev_pm_test_driver_flags(dev, DPM_FLAG_NEVER_SKIP);
1954 spin_unlock_irq(&dev->power.lock);
1955 return 0;
1956}
1957
1958
1959
1960
1961
1962
1963
1964int dpm_prepare(pm_message_t state)
1965{
1966 int error = 0;
1967
1968 trace_suspend_resume(TPS("dpm_prepare"), state.event, true);
1969 might_sleep();
1970
1971
1972
1973
1974
1975
1976 wait_for_device_probe();
1977
1978
1979
1980
1981
1982
1983 device_block_probing();
1984
1985 mutex_lock(&dpm_list_mtx);
1986 while (!list_empty(&dpm_list)) {
1987 struct device *dev = to_device(dpm_list.next);
1988
1989 get_device(dev);
1990 mutex_unlock(&dpm_list_mtx);
1991
1992 trace_device_pm_callback_start(dev, "", state.event);
1993 error = device_prepare(dev, state);
1994 trace_device_pm_callback_end(dev, error);
1995
1996 mutex_lock(&dpm_list_mtx);
1997 if (error) {
1998 if (error == -EAGAIN) {
1999 put_device(dev);
2000 error = 0;
2001 continue;
2002 }
2003 pr_info("Device %s not prepared for power transition: code %d\n",
2004 dev_name(dev), error);
2005 put_device(dev);
2006 break;
2007 }
2008 dev->power.is_prepared = true;
2009 if (!list_empty(&dev->power.entry))
2010 list_move_tail(&dev->power.entry, &dpm_prepared_list);
2011 put_device(dev);
2012 }
2013 mutex_unlock(&dpm_list_mtx);
2014 trace_suspend_resume(TPS("dpm_prepare"), state.event, false);
2015 return error;
2016}
2017
2018
2019
2020
2021
2022
2023
2024
2025int dpm_suspend_start(pm_message_t state)
2026{
2027 ktime_t starttime = ktime_get();
2028 int error;
2029
2030 error = dpm_prepare(state);
2031 if (error) {
2032 suspend_stats.failed_prepare++;
2033 dpm_save_failed_step(SUSPEND_PREPARE);
2034 } else
2035 error = dpm_suspend(state);
2036 dpm_show_time(starttime, state, error, "start");
2037 return error;
2038}
2039EXPORT_SYMBOL_GPL(dpm_suspend_start);
2040
2041void __suspend_report_result(const char *function, void *fn, int ret)
2042{
2043 if (ret)
2044 pr_err("%s(): %pS returns %d\n", function, fn, ret);
2045}
2046EXPORT_SYMBOL_GPL(__suspend_report_result);
2047
2048
2049
2050
2051
2052
2053int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
2054{
2055 dpm_wait(dev, subordinate->power.async_suspend);
2056 return async_error;
2057}
2058EXPORT_SYMBOL_GPL(device_pm_wait_for_dev);
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
2069{
2070 struct device *dev;
2071
2072 if (!fn)
2073 return;
2074
2075 device_pm_lock();
2076 list_for_each_entry(dev, &dpm_list, power.entry)
2077 fn(dev, data);
2078 device_pm_unlock();
2079}
2080EXPORT_SYMBOL_GPL(dpm_for_each_dev);
2081
2082static bool pm_ops_is_empty(const struct dev_pm_ops *ops)
2083{
2084 if (!ops)
2085 return true;
2086
2087 return !ops->prepare &&
2088 !ops->suspend &&
2089 !ops->suspend_late &&
2090 !ops->suspend_noirq &&
2091 !ops->resume_noirq &&
2092 !ops->resume_early &&
2093 !ops->resume &&
2094 !ops->complete;
2095}
2096
2097void device_pm_check_callbacks(struct device *dev)
2098{
2099 spin_lock_irq(&dev->power.lock);
2100 dev->power.no_pm_callbacks =
2101 (!dev->bus || (pm_ops_is_empty(dev->bus->pm) &&
2102 !dev->bus->suspend && !dev->bus->resume)) &&
2103 (!dev->class || pm_ops_is_empty(dev->class->pm)) &&
2104 (!dev->type || pm_ops_is_empty(dev->type->pm)) &&
2105 (!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) &&
2106 (!dev->driver || (pm_ops_is_empty(dev->driver->pm) &&
2107 !dev->driver->suspend && !dev->driver->resume));
2108 spin_unlock_irq(&dev->power.lock);
2109}
2110
2111bool dev_pm_smart_suspend_and_suspended(struct device *dev)
2112{
2113 return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) &&
2114 pm_runtime_status_suspended(dev);
2115}
2116