Line data Source code
1 : // SPDX-License-Identifier: GPL-2.0
2 : /*
3 : * drivers/base/power/main.c - Where the driver meets power management.
4 : *
5 : * Copyright (c) 2003 Patrick Mochel
6 : * Copyright (c) 2003 Open Source Development Lab
7 : *
8 : * The driver model core calls device_pm_add() when a device is registered.
9 : * This will initialize the embedded device_pm_info object in the device
10 : * and add it to the list of power-controlled devices. sysfs entries for
11 : * controlling device power management will also be added.
12 : *
13 : * A separate list is used for keeping track of power info, because the power
14 : * domain dependencies may differ from the ancestral dependencies that the
15 : * subsystem list maintains.
16 : */
17 :
18 : #define pr_fmt(fmt) "PM: " fmt
19 : #define dev_fmt pr_fmt
20 :
21 : #include <linux/device.h>
22 : #include <linux/export.h>
23 : #include <linux/mutex.h>
24 : #include <linux/pm.h>
25 : #include <linux/pm_runtime.h>
26 : #include <linux/pm-trace.h>
27 : #include <linux/pm_wakeirq.h>
28 : #include <linux/interrupt.h>
29 : #include <linux/sched.h>
30 : #include <linux/sched/debug.h>
31 : #include <linux/async.h>
32 : #include <linux/suspend.h>
33 : #include <trace/events/power.h>
34 : #include <linux/cpufreq.h>
35 : #include <linux/devfreq.h>
36 : #include <linux/timer.h>
37 :
38 : #include "../base.h"
39 : #include "power.h"
40 :
41 : typedef int (*pm_callback_t)(struct device *);
42 :
43 : #define list_for_each_entry_rcu_locked(pos, head, member) \
44 : list_for_each_entry_rcu(pos, head, member, \
45 : device_links_read_lock_held())
46 :
47 : /*
48 : * The entries in the dpm_list list are in a depth first order, simply
49 : * because children are guaranteed to be discovered after parents, and
50 : * are inserted at the back of the list on discovery.
51 : *
52 : * Since device_pm_add() may be called with a device lock held,
53 : * we must never try to acquire a device lock while holding
54 : * dpm_list_mutex.
55 : */
56 :
57 : LIST_HEAD(dpm_list);
58 : static LIST_HEAD(dpm_prepared_list);
59 : static LIST_HEAD(dpm_suspended_list);
60 : static LIST_HEAD(dpm_late_early_list);
61 : static LIST_HEAD(dpm_noirq_list);
62 :
63 : struct suspend_stats suspend_stats;
64 : static DEFINE_MUTEX(dpm_list_mtx);
65 : static pm_message_t pm_transition;
66 :
67 : static int async_error;
68 :
69 0 : static const char *pm_verb(int event)
70 : {
71 0 : switch (event) {
72 : case PM_EVENT_SUSPEND:
73 : return "suspend";
74 : case PM_EVENT_RESUME:
75 0 : return "resume";
76 : case PM_EVENT_FREEZE:
77 0 : return "freeze";
78 : case PM_EVENT_QUIESCE:
79 0 : return "quiesce";
80 : case PM_EVENT_HIBERNATE:
81 0 : return "hibernate";
82 : case PM_EVENT_THAW:
83 0 : return "thaw";
84 : case PM_EVENT_RESTORE:
85 0 : return "restore";
86 : case PM_EVENT_RECOVER:
87 0 : return "recover";
88 : default:
89 0 : return "(unknown PM event)";
90 : }
91 : }
92 :
93 : /**
94 : * device_pm_sleep_init - Initialize system suspend-related device fields.
95 : * @dev: Device object being initialized.
96 : */
97 570 : void device_pm_sleep_init(struct device *dev)
98 : {
99 570 : dev->power.is_prepared = false;
100 570 : dev->power.is_suspended = false;
101 570 : dev->power.is_noirq_suspended = false;
102 570 : dev->power.is_late_suspended = false;
103 1140 : init_completion(&dev->power.completion);
104 570 : complete_all(&dev->power.completion);
105 570 : dev->power.wakeup = NULL;
106 1140 : INIT_LIST_HEAD(&dev->power.entry);
107 570 : }
108 :
109 : /**
110 : * device_pm_lock - Lock the list of active devices used by the PM core.
111 : */
112 0 : void device_pm_lock(void)
113 : {
114 0 : mutex_lock(&dpm_list_mtx);
115 0 : }
116 :
117 : /**
118 : * device_pm_unlock - Unlock the list of active devices used by the PM core.
119 : */
120 0 : void device_pm_unlock(void)
121 : {
122 0 : mutex_unlock(&dpm_list_mtx);
123 0 : }
124 :
125 : /**
126 : * device_pm_add - Add a device to the PM core's list of active devices.
127 : * @dev: Device to add to the list.
128 : */
129 554 : void device_pm_add(struct device *dev)
130 : {
131 : /* Skip PM setup/initialization. */
132 554 : if (device_pm_not_required(dev))
133 : return;
134 :
135 : pr_debug("Adding info for %s:%s\n",
136 : dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
137 554 : device_pm_check_callbacks(dev);
138 554 : mutex_lock(&dpm_list_mtx);
139 554 : if (dev->parent && dev->parent->power.is_prepared)
140 0 : dev_warn(dev, "parent %s should not be sleeping\n",
141 : dev_name(dev->parent));
142 1108 : list_add_tail(&dev->power.entry, &dpm_list);
143 554 : dev->power.in_dpm_list = true;
144 554 : mutex_unlock(&dpm_list_mtx);
145 : }
146 :
147 : /**
148 : * device_pm_remove - Remove a device from the PM core's list of active devices.
149 : * @dev: Device to be removed from the list.
150 : */
151 18 : void device_pm_remove(struct device *dev)
152 : {
153 18 : if (device_pm_not_required(dev))
154 : return;
155 :
156 : pr_debug("Removing info for %s:%s\n",
157 : dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
158 18 : complete_all(&dev->power.completion);
159 18 : mutex_lock(&dpm_list_mtx);
160 36 : list_del_init(&dev->power.entry);
161 18 : dev->power.in_dpm_list = false;
162 18 : mutex_unlock(&dpm_list_mtx);
163 18 : device_wakeup_disable(dev);
164 18 : pm_runtime_remove(dev);
165 18 : device_pm_check_callbacks(dev);
166 : }
167 :
168 : /**
169 : * device_pm_move_before - Move device in the PM core's list of active devices.
170 : * @deva: Device to move in dpm_list.
171 : * @devb: Device @deva should come before.
172 : */
173 0 : void device_pm_move_before(struct device *deva, struct device *devb)
174 : {
175 : pr_debug("Moving %s:%s before %s:%s\n",
176 : deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
177 : devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
178 : /* Delete deva from dpm_list and reinsert before devb. */
179 0 : list_move_tail(&deva->power.entry, &devb->power.entry);
180 0 : }
181 :
182 : /**
183 : * device_pm_move_after - Move device in the PM core's list of active devices.
184 : * @deva: Device to move in dpm_list.
185 : * @devb: Device @deva should come after.
186 : */
187 0 : void device_pm_move_after(struct device *deva, struct device *devb)
188 : {
189 : pr_debug("Moving %s:%s after %s:%s\n",
190 : deva->bus ? deva->bus->name : "No Bus", dev_name(deva),
191 : devb->bus ? devb->bus->name : "No Bus", dev_name(devb));
192 : /* Delete deva from dpm_list and reinsert after devb. */
193 0 : list_move(&deva->power.entry, &devb->power.entry);
194 0 : }
195 :
196 : /**
197 : * device_pm_move_last - Move device to end of the PM core's list of devices.
198 : * @dev: Device to move in dpm_list.
199 : */
200 0 : void device_pm_move_last(struct device *dev)
201 : {
202 : pr_debug("Moving %s:%s to end of list\n",
203 : dev->bus ? dev->bus->name : "No Bus", dev_name(dev));
204 0 : list_move_tail(&dev->power.entry, &dpm_list);
205 0 : }
206 :
207 : static ktime_t initcall_debug_start(struct device *dev, void *cb)
208 : {
209 : if (!pm_print_times_enabled)
210 : return 0;
211 :
212 : dev_info(dev, "calling %pS @ %i, parent: %s\n", cb,
213 : task_pid_nr(current),
214 : dev->parent ? dev_name(dev->parent) : "none");
215 : return ktime_get();
216 : }
217 :
218 : static void initcall_debug_report(struct device *dev, ktime_t calltime,
219 : void *cb, int error)
220 : {
221 : ktime_t rettime;
222 :
223 : if (!pm_print_times_enabled)
224 : return;
225 :
226 : rettime = ktime_get();
227 : dev_info(dev, "%pS returned %d after %Ld usecs\n", cb, error,
228 : (unsigned long long)ktime_us_delta(rettime, calltime));
229 : }
230 :
231 : /**
232 : * dpm_wait - Wait for a PM operation to complete.
233 : * @dev: Device to wait for.
234 : * @async: If unset, wait only if the device's power.async_suspend flag is set.
235 : */
236 0 : static void dpm_wait(struct device *dev, bool async)
237 : {
238 0 : if (!dev)
239 : return;
240 :
241 0 : if (async || (pm_async_enabled && dev->power.async_suspend))
242 0 : wait_for_completion(&dev->power.completion);
243 : }
244 :
245 0 : static int dpm_wait_fn(struct device *dev, void *async_ptr)
246 : {
247 0 : dpm_wait(dev, *((bool *)async_ptr));
248 0 : return 0;
249 : }
250 :
251 : static void dpm_wait_for_children(struct device *dev, bool async)
252 : {
253 0 : device_for_each_child(dev, &async, dpm_wait_fn);
254 : }
255 :
256 0 : static void dpm_wait_for_suppliers(struct device *dev, bool async)
257 : {
258 : struct device_link *link;
259 : int idx;
260 :
261 0 : idx = device_links_read_lock();
262 :
263 : /*
264 : * If the supplier goes away right after we've checked the link to it,
265 : * we'll wait for its completion to change the state, but that's fine,
266 : * because the only things that will block as a result are the SRCU
267 : * callbacks freeing the link objects for the links in the list we're
268 : * walking.
269 : */
270 0 : list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
271 0 : if (READ_ONCE(link->status) != DL_STATE_DORMANT)
272 0 : dpm_wait(link->supplier, async);
273 :
274 0 : device_links_read_unlock(idx);
275 0 : }
276 :
277 0 : static bool dpm_wait_for_superior(struct device *dev, bool async)
278 : {
279 : struct device *parent;
280 :
281 : /*
282 : * If the device is resumed asynchronously and the parent's callback
283 : * deletes both the device and the parent itself, the parent object may
284 : * be freed while this function is running, so avoid that by reference
285 : * counting the parent once more unless the device has been deleted
286 : * already (in which case return right away).
287 : */
288 0 : mutex_lock(&dpm_list_mtx);
289 :
290 0 : if (!device_pm_initialized(dev)) {
291 0 : mutex_unlock(&dpm_list_mtx);
292 0 : return false;
293 : }
294 :
295 0 : parent = get_device(dev->parent);
296 :
297 0 : mutex_unlock(&dpm_list_mtx);
298 :
299 0 : dpm_wait(parent, async);
300 0 : put_device(parent);
301 :
302 0 : dpm_wait_for_suppliers(dev, async);
303 :
304 : /*
305 : * If the parent's callback has deleted the device, attempting to resume
306 : * it would be invalid, so avoid doing that then.
307 : */
308 0 : return device_pm_initialized(dev);
309 : }
310 :
311 0 : static void dpm_wait_for_consumers(struct device *dev, bool async)
312 : {
313 : struct device_link *link;
314 : int idx;
315 :
316 0 : idx = device_links_read_lock();
317 :
318 : /*
319 : * The status of a device link can only be changed from "dormant" by a
320 : * probe, but that cannot happen during system suspend/resume. In
321 : * theory it can change to "dormant" at that time, but then it is
322 : * reasonable to wait for the target device anyway (eg. if it goes
323 : * away, it's better to wait for it to go away completely and then
324 : * continue instead of trying to continue in parallel with its
325 : * unregistration).
326 : */
327 0 : list_for_each_entry_rcu_locked(link, &dev->links.consumers, s_node)
328 0 : if (READ_ONCE(link->status) != DL_STATE_DORMANT)
329 0 : dpm_wait(link->consumer, async);
330 :
331 0 : device_links_read_unlock(idx);
332 0 : }
333 :
334 0 : static void dpm_wait_for_subordinate(struct device *dev, bool async)
335 : {
336 0 : dpm_wait_for_children(dev, async);
337 0 : dpm_wait_for_consumers(dev, async);
338 0 : }
339 :
340 : /**
341 : * pm_op - Return the PM operation appropriate for given PM event.
342 : * @ops: PM operations to choose from.
343 : * @state: PM transition of the system being carried out.
344 : */
345 : static pm_callback_t pm_op(const struct dev_pm_ops *ops, pm_message_t state)
346 : {
347 0 : switch (state.event) {
348 : #ifdef CONFIG_SUSPEND
349 : case PM_EVENT_SUSPEND:
350 0 : return ops->suspend;
351 : case PM_EVENT_RESUME:
352 0 : return ops->resume;
353 : #endif /* CONFIG_SUSPEND */
354 : #ifdef CONFIG_HIBERNATE_CALLBACKS
355 : case PM_EVENT_FREEZE:
356 : case PM_EVENT_QUIESCE:
357 : return ops->freeze;
358 : case PM_EVENT_HIBERNATE:
359 : return ops->poweroff;
360 : case PM_EVENT_THAW:
361 : case PM_EVENT_RECOVER:
362 : return ops->thaw;
363 : case PM_EVENT_RESTORE:
364 : return ops->restore;
365 : #endif /* CONFIG_HIBERNATE_CALLBACKS */
366 : }
367 :
368 : return NULL;
369 : }
370 :
371 : /**
372 : * pm_late_early_op - Return the PM operation appropriate for given PM event.
373 : * @ops: PM operations to choose from.
374 : * @state: PM transition of the system being carried out.
375 : *
376 : * Runtime PM is disabled for @dev while this function is being executed.
377 : */
378 : static pm_callback_t pm_late_early_op(const struct dev_pm_ops *ops,
379 : pm_message_t state)
380 : {
381 0 : switch (state.event) {
382 : #ifdef CONFIG_SUSPEND
383 : case PM_EVENT_SUSPEND:
384 0 : return ops->suspend_late;
385 : case PM_EVENT_RESUME:
386 0 : return ops->resume_early;
387 : #endif /* CONFIG_SUSPEND */
388 : #ifdef CONFIG_HIBERNATE_CALLBACKS
389 : case PM_EVENT_FREEZE:
390 : case PM_EVENT_QUIESCE:
391 : return ops->freeze_late;
392 : case PM_EVENT_HIBERNATE:
393 : return ops->poweroff_late;
394 : case PM_EVENT_THAW:
395 : case PM_EVENT_RECOVER:
396 : return ops->thaw_early;
397 : case PM_EVENT_RESTORE:
398 : return ops->restore_early;
399 : #endif /* CONFIG_HIBERNATE_CALLBACKS */
400 : }
401 :
402 : return NULL;
403 : }
404 :
405 : /**
406 : * pm_noirq_op - Return the PM operation appropriate for given PM event.
407 : * @ops: PM operations to choose from.
408 : * @state: PM transition of the system being carried out.
409 : *
410 : * The driver of @dev will not receive interrupts while this function is being
411 : * executed.
412 : */
413 : static pm_callback_t pm_noirq_op(const struct dev_pm_ops *ops, pm_message_t state)
414 : {
415 0 : switch (state.event) {
416 : #ifdef CONFIG_SUSPEND
417 : case PM_EVENT_SUSPEND:
418 0 : return ops->suspend_noirq;
419 : case PM_EVENT_RESUME:
420 0 : return ops->resume_noirq;
421 : #endif /* CONFIG_SUSPEND */
422 : #ifdef CONFIG_HIBERNATE_CALLBACKS
423 : case PM_EVENT_FREEZE:
424 : case PM_EVENT_QUIESCE:
425 : return ops->freeze_noirq;
426 : case PM_EVENT_HIBERNATE:
427 : return ops->poweroff_noirq;
428 : case PM_EVENT_THAW:
429 : case PM_EVENT_RECOVER:
430 : return ops->thaw_noirq;
431 : case PM_EVENT_RESTORE:
432 : return ops->restore_noirq;
433 : #endif /* CONFIG_HIBERNATE_CALLBACKS */
434 : }
435 :
436 : return NULL;
437 : }
438 :
439 : static void pm_dev_dbg(struct device *dev, pm_message_t state, const char *info)
440 : {
441 : dev_dbg(dev, "%s%s%s driver flags: %x\n", info, pm_verb(state.event),
442 : ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
443 : ", may wakeup" : "", dev->power.driver_flags);
444 : }
445 :
446 : static void pm_dev_err(struct device *dev, pm_message_t state, const char *info,
447 : int error)
448 : {
449 0 : dev_err(dev, "failed to %s%s: error %d\n", pm_verb(state.event), info,
450 : error);
451 : }
452 :
453 : static void dpm_show_time(ktime_t starttime, pm_message_t state, int error,
454 : const char *info)
455 : {
456 : ktime_t calltime;
457 : u64 usecs64;
458 : int usecs;
459 :
460 0 : calltime = ktime_get();
461 0 : usecs64 = ktime_to_ns(ktime_sub(calltime, starttime));
462 0 : do_div(usecs64, NSEC_PER_USEC);
463 0 : usecs = usecs64;
464 : if (usecs == 0)
465 : usecs = 1;
466 :
467 : pm_pr_dbg("%s%s%s of devices %s after %ld.%03ld msecs\n",
468 : info ?: "", info ? " " : "", pm_verb(state.event),
469 : error ? "aborted" : "complete",
470 : usecs / USEC_PER_MSEC, usecs % USEC_PER_MSEC);
471 : }
472 :
473 0 : static int dpm_run_callback(pm_callback_t cb, struct device *dev,
474 : pm_message_t state, const char *info)
475 : {
476 : ktime_t calltime;
477 : int error;
478 :
479 0 : if (!cb)
480 : return 0;
481 :
482 0 : calltime = initcall_debug_start(dev, cb);
483 :
484 0 : pm_dev_dbg(dev, state, info);
485 0 : trace_device_pm_callback_start(dev, info, state.event);
486 0 : error = cb(dev);
487 0 : trace_device_pm_callback_end(dev, error);
488 : suspend_report_result(dev, cb, error);
489 :
490 : initcall_debug_report(dev, calltime, cb, error);
491 :
492 : return error;
493 : }
494 :
495 : #ifdef CONFIG_DPM_WATCHDOG
496 : struct dpm_watchdog {
497 : struct device *dev;
498 : struct task_struct *tsk;
499 : struct timer_list timer;
500 : };
501 :
502 : #define DECLARE_DPM_WATCHDOG_ON_STACK(wd) \
503 : struct dpm_watchdog wd
504 :
505 : /**
506 : * dpm_watchdog_handler - Driver suspend / resume watchdog handler.
507 : * @t: The timer that PM watchdog depends on.
508 : *
509 : * Called when a driver has timed out suspending or resuming.
510 : * There's not much we can do here to recover so panic() to
511 : * capture a crash-dump in pstore.
512 : */
513 : static void dpm_watchdog_handler(struct timer_list *t)
514 : {
515 : struct dpm_watchdog *wd = from_timer(wd, t, timer);
516 :
517 : dev_emerg(wd->dev, "**** DPM device timeout ****\n");
518 : show_stack(wd->tsk, NULL, KERN_EMERG);
519 : panic("%s %s: unrecoverable failure\n",
520 : dev_driver_string(wd->dev), dev_name(wd->dev));
521 : }
522 :
523 : /**
524 : * dpm_watchdog_set - Enable pm watchdog for given device.
525 : * @wd: Watchdog. Must be allocated on the stack.
526 : * @dev: Device to handle.
527 : */
528 : static void dpm_watchdog_set(struct dpm_watchdog *wd, struct device *dev)
529 : {
530 : struct timer_list *timer = &wd->timer;
531 :
532 : wd->dev = dev;
533 : wd->tsk = current;
534 :
535 : timer_setup_on_stack(timer, dpm_watchdog_handler, 0);
536 : /* use same timeout value for both suspend and resume */
537 : timer->expires = jiffies + HZ * CONFIG_DPM_WATCHDOG_TIMEOUT;
538 : add_timer(timer);
539 : }
540 :
541 : /**
542 : * dpm_watchdog_clear - Disable suspend/resume watchdog.
543 : * @wd: Watchdog to disable.
544 : */
545 : static void dpm_watchdog_clear(struct dpm_watchdog *wd)
546 : {
547 : struct timer_list *timer = &wd->timer;
548 :
549 : del_timer_sync(timer);
550 : destroy_timer_on_stack(timer);
551 : }
552 : #else
553 : #define DECLARE_DPM_WATCHDOG_ON_STACK(wd)
554 : #define dpm_watchdog_set(x, y)
555 : #define dpm_watchdog_clear(x)
556 : #endif
557 :
558 : /*------------------------- Resume routines -------------------------*/
559 :
560 : /**
561 : * dev_pm_skip_resume - System-wide device resume optimization check.
562 : * @dev: Target device.
563 : *
564 : * Return:
565 : * - %false if the transition under way is RESTORE.
566 : * - Return value of dev_pm_skip_suspend() if the transition under way is THAW.
567 : * - The logical negation of %power.must_resume otherwise (that is, when the
568 : * transition under way is RESUME).
569 : */
570 0 : bool dev_pm_skip_resume(struct device *dev)
571 : {
572 0 : if (pm_transition.event == PM_EVENT_RESTORE)
573 : return false;
574 :
575 0 : if (pm_transition.event == PM_EVENT_THAW)
576 0 : return dev_pm_skip_suspend(dev);
577 :
578 0 : return !dev->power.must_resume;
579 : }
580 :
581 : /**
582 : * device_resume_noirq - Execute a "noirq resume" callback for given device.
583 : * @dev: Device to handle.
584 : * @state: PM transition of the system being carried out.
585 : * @async: If true, the device is being resumed asynchronously.
586 : *
587 : * The driver of @dev will not receive interrupts while this function is being
588 : * executed.
589 : */
590 0 : static int device_resume_noirq(struct device *dev, pm_message_t state, bool async)
591 : {
592 0 : pm_callback_t callback = NULL;
593 0 : const char *info = NULL;
594 : bool skip_resume;
595 0 : int error = 0;
596 :
597 : TRACE_DEVICE(dev);
598 : TRACE_RESUME(0);
599 :
600 0 : if (dev->power.syscore || dev->power.direct_complete)
601 : goto Out;
602 :
603 0 : if (!dev->power.is_noirq_suspended)
604 : goto Out;
605 :
606 0 : if (!dpm_wait_for_superior(dev, async))
607 : goto Out;
608 :
609 0 : skip_resume = dev_pm_skip_resume(dev);
610 : /*
611 : * If the driver callback is skipped below or by the middle layer
612 : * callback and device_resume_early() also skips the driver callback for
613 : * this device later, it needs to appear as "suspended" to PM-runtime,
614 : * so change its status accordingly.
615 : *
616 : * Otherwise, the device is going to be resumed, so set its PM-runtime
617 : * status to "active", but do that only if DPM_FLAG_SMART_SUSPEND is set
618 : * to avoid confusing drivers that don't use it.
619 : */
620 0 : if (skip_resume)
621 : pm_runtime_set_suspended(dev);
622 0 : else if (dev_pm_skip_suspend(dev))
623 : pm_runtime_set_active(dev);
624 :
625 0 : if (dev->pm_domain) {
626 0 : info = "noirq power domain ";
627 0 : callback = pm_noirq_op(&dev->pm_domain->ops, state);
628 0 : } else if (dev->type && dev->type->pm) {
629 0 : info = "noirq type ";
630 0 : callback = pm_noirq_op(dev->type->pm, state);
631 0 : } else if (dev->class && dev->class->pm) {
632 0 : info = "noirq class ";
633 0 : callback = pm_noirq_op(dev->class->pm, state);
634 0 : } else if (dev->bus && dev->bus->pm) {
635 0 : info = "noirq bus ";
636 0 : callback = pm_noirq_op(dev->bus->pm, state);
637 : }
638 0 : if (callback)
639 : goto Run;
640 :
641 0 : if (skip_resume)
642 : goto Skip;
643 :
644 0 : if (dev->driver && dev->driver->pm) {
645 0 : info = "noirq driver ";
646 0 : callback = pm_noirq_op(dev->driver->pm, state);
647 : }
648 :
649 : Run:
650 0 : error = dpm_run_callback(callback, dev, state, info);
651 :
652 : Skip:
653 0 : dev->power.is_noirq_suspended = false;
654 :
655 : Out:
656 0 : complete_all(&dev->power.completion);
657 : TRACE_RESUME(error);
658 0 : return error;
659 : }
660 :
661 : static bool is_async(struct device *dev)
662 : {
663 0 : return dev->power.async_suspend && pm_async_enabled
664 0 : && !pm_trace_is_enabled();
665 : }
666 :
667 0 : static bool dpm_async_fn(struct device *dev, async_func_t func)
668 : {
669 0 : reinit_completion(&dev->power.completion);
670 :
671 0 : if (is_async(dev)) {
672 0 : get_device(dev);
673 0 : async_schedule_dev(func, dev);
674 0 : return true;
675 : }
676 :
677 : return false;
678 : }
679 :
680 0 : static void async_resume_noirq(void *data, async_cookie_t cookie)
681 : {
682 0 : struct device *dev = (struct device *)data;
683 : int error;
684 :
685 0 : error = device_resume_noirq(dev, pm_transition, true);
686 0 : if (error)
687 : pm_dev_err(dev, pm_transition, " async", error);
688 :
689 0 : put_device(dev);
690 0 : }
691 :
692 0 : static void dpm_noirq_resume_devices(pm_message_t state)
693 : {
694 : struct device *dev;
695 0 : ktime_t starttime = ktime_get();
696 :
697 0 : trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, true);
698 0 : mutex_lock(&dpm_list_mtx);
699 0 : pm_transition = state;
700 :
701 : /*
702 : * Advanced the async threads upfront,
703 : * in case the starting of async threads is
704 : * delayed by non-async resuming devices.
705 : */
706 0 : list_for_each_entry(dev, &dpm_noirq_list, power.entry)
707 0 : dpm_async_fn(dev, async_resume_noirq);
708 :
709 0 : while (!list_empty(&dpm_noirq_list)) {
710 0 : dev = to_device(dpm_noirq_list.next);
711 0 : get_device(dev);
712 0 : list_move_tail(&dev->power.entry, &dpm_late_early_list);
713 :
714 0 : mutex_unlock(&dpm_list_mtx);
715 :
716 0 : if (!is_async(dev)) {
717 : int error;
718 :
719 0 : error = device_resume_noirq(dev, state, false);
720 0 : if (error) {
721 0 : suspend_stats.failed_resume_noirq++;
722 0 : dpm_save_failed_step(SUSPEND_RESUME_NOIRQ);
723 0 : dpm_save_failed_dev(dev_name(dev));
724 : pm_dev_err(dev, state, " noirq", error);
725 : }
726 : }
727 :
728 0 : put_device(dev);
729 :
730 0 : mutex_lock(&dpm_list_mtx);
731 : }
732 0 : mutex_unlock(&dpm_list_mtx);
733 0 : async_synchronize_full();
734 0 : dpm_show_time(starttime, state, 0, "noirq");
735 0 : trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false);
736 0 : }
737 :
738 : /**
739 : * dpm_resume_noirq - Execute "noirq resume" callbacks for all devices.
740 : * @state: PM transition of the system being carried out.
741 : *
742 : * Invoke the "noirq" resume callbacks for all devices in dpm_noirq_list and
743 : * allow device drivers' interrupt handlers to be called.
744 : */
745 0 : void dpm_resume_noirq(pm_message_t state)
746 : {
747 0 : dpm_noirq_resume_devices(state);
748 :
749 0 : resume_device_irqs();
750 0 : device_wakeup_disarm_wake_irqs();
751 0 : }
752 :
753 : /**
754 : * device_resume_early - Execute an "early resume" callback for given device.
755 : * @dev: Device to handle.
756 : * @state: PM transition of the system being carried out.
757 : * @async: If true, the device is being resumed asynchronously.
758 : *
759 : * Runtime PM is disabled for @dev while this function is being executed.
760 : */
761 0 : static int device_resume_early(struct device *dev, pm_message_t state, bool async)
762 : {
763 0 : pm_callback_t callback = NULL;
764 0 : const char *info = NULL;
765 0 : int error = 0;
766 :
767 : TRACE_DEVICE(dev);
768 : TRACE_RESUME(0);
769 :
770 0 : if (dev->power.syscore || dev->power.direct_complete)
771 : goto Out;
772 :
773 0 : if (!dev->power.is_late_suspended)
774 : goto Out;
775 :
776 0 : if (!dpm_wait_for_superior(dev, async))
777 : goto Out;
778 :
779 0 : if (dev->pm_domain) {
780 0 : info = "early power domain ";
781 0 : callback = pm_late_early_op(&dev->pm_domain->ops, state);
782 0 : } else if (dev->type && dev->type->pm) {
783 0 : info = "early type ";
784 0 : callback = pm_late_early_op(dev->type->pm, state);
785 0 : } else if (dev->class && dev->class->pm) {
786 0 : info = "early class ";
787 0 : callback = pm_late_early_op(dev->class->pm, state);
788 0 : } else if (dev->bus && dev->bus->pm) {
789 0 : info = "early bus ";
790 0 : callback = pm_late_early_op(dev->bus->pm, state);
791 : }
792 0 : if (callback)
793 : goto Run;
794 :
795 0 : if (dev_pm_skip_resume(dev))
796 : goto Skip;
797 :
798 0 : if (dev->driver && dev->driver->pm) {
799 0 : info = "early driver ";
800 0 : callback = pm_late_early_op(dev->driver->pm, state);
801 : }
802 :
803 : Run:
804 0 : error = dpm_run_callback(callback, dev, state, info);
805 :
806 : Skip:
807 0 : dev->power.is_late_suspended = false;
808 :
809 : Out:
810 : TRACE_RESUME(error);
811 :
812 0 : pm_runtime_enable(dev);
813 0 : complete_all(&dev->power.completion);
814 0 : return error;
815 : }
816 :
817 0 : static void async_resume_early(void *data, async_cookie_t cookie)
818 : {
819 0 : struct device *dev = (struct device *)data;
820 : int error;
821 :
822 0 : error = device_resume_early(dev, pm_transition, true);
823 0 : if (error)
824 : pm_dev_err(dev, pm_transition, " async", error);
825 :
826 0 : put_device(dev);
827 0 : }
828 :
829 : /**
830 : * dpm_resume_early - Execute "early resume" callbacks for all devices.
831 : * @state: PM transition of the system being carried out.
832 : */
833 0 : void dpm_resume_early(pm_message_t state)
834 : {
835 : struct device *dev;
836 0 : ktime_t starttime = ktime_get();
837 :
838 0 : trace_suspend_resume(TPS("dpm_resume_early"), state.event, true);
839 0 : mutex_lock(&dpm_list_mtx);
840 0 : pm_transition = state;
841 :
842 : /*
843 : * Advanced the async threads upfront,
844 : * in case the starting of async threads is
845 : * delayed by non-async resuming devices.
846 : */
847 0 : list_for_each_entry(dev, &dpm_late_early_list, power.entry)
848 0 : dpm_async_fn(dev, async_resume_early);
849 :
850 0 : while (!list_empty(&dpm_late_early_list)) {
851 0 : dev = to_device(dpm_late_early_list.next);
852 0 : get_device(dev);
853 0 : list_move_tail(&dev->power.entry, &dpm_suspended_list);
854 :
855 0 : mutex_unlock(&dpm_list_mtx);
856 :
857 0 : if (!is_async(dev)) {
858 : int error;
859 :
860 0 : error = device_resume_early(dev, state, false);
861 0 : if (error) {
862 0 : suspend_stats.failed_resume_early++;
863 0 : dpm_save_failed_step(SUSPEND_RESUME_EARLY);
864 0 : dpm_save_failed_dev(dev_name(dev));
865 : pm_dev_err(dev, state, " early", error);
866 : }
867 : }
868 :
869 0 : put_device(dev);
870 :
871 0 : mutex_lock(&dpm_list_mtx);
872 : }
873 0 : mutex_unlock(&dpm_list_mtx);
874 0 : async_synchronize_full();
875 0 : dpm_show_time(starttime, state, 0, "early");
876 0 : trace_suspend_resume(TPS("dpm_resume_early"), state.event, false);
877 0 : }
878 :
879 : /**
880 : * dpm_resume_start - Execute "noirq" and "early" device callbacks.
881 : * @state: PM transition of the system being carried out.
882 : */
883 0 : void dpm_resume_start(pm_message_t state)
884 : {
885 : dpm_resume_noirq(state);
886 0 : dpm_resume_early(state);
887 0 : }
888 : EXPORT_SYMBOL_GPL(dpm_resume_start);
889 :
890 : /**
891 : * device_resume - Execute "resume" callbacks for given device.
892 : * @dev: Device to handle.
893 : * @state: PM transition of the system being carried out.
894 : * @async: If true, the device is being resumed asynchronously.
895 : */
896 0 : static int device_resume(struct device *dev, pm_message_t state, bool async)
897 : {
898 0 : pm_callback_t callback = NULL;
899 0 : const char *info = NULL;
900 0 : int error = 0;
901 : DECLARE_DPM_WATCHDOG_ON_STACK(wd);
902 :
903 : TRACE_DEVICE(dev);
904 : TRACE_RESUME(0);
905 :
906 0 : if (dev->power.syscore)
907 : goto Complete;
908 :
909 0 : if (dev->power.direct_complete) {
910 : /* Match the pm_runtime_disable() in __device_suspend(). */
911 0 : pm_runtime_enable(dev);
912 0 : goto Complete;
913 : }
914 :
915 0 : if (!dpm_wait_for_superior(dev, async))
916 : goto Complete;
917 :
918 : dpm_watchdog_set(&wd, dev);
919 0 : device_lock(dev);
920 :
921 : /*
922 : * This is a fib. But we'll allow new children to be added below
923 : * a resumed device, even if the device hasn't been completed yet.
924 : */
925 0 : dev->power.is_prepared = false;
926 :
927 0 : if (!dev->power.is_suspended)
928 : goto Unlock;
929 :
930 0 : if (dev->pm_domain) {
931 0 : info = "power domain ";
932 0 : callback = pm_op(&dev->pm_domain->ops, state);
933 : goto Driver;
934 : }
935 :
936 0 : if (dev->type && dev->type->pm) {
937 0 : info = "type ";
938 0 : callback = pm_op(dev->type->pm, state);
939 : goto Driver;
940 : }
941 :
942 0 : if (dev->class && dev->class->pm) {
943 0 : info = "class ";
944 0 : callback = pm_op(dev->class->pm, state);
945 : goto Driver;
946 : }
947 :
948 0 : if (dev->bus) {
949 0 : if (dev->bus->pm) {
950 0 : info = "bus ";
951 0 : callback = pm_op(dev->bus->pm, state);
952 0 : } else if (dev->bus->resume) {
953 : info = "legacy bus ";
954 : callback = dev->bus->resume;
955 : goto End;
956 : }
957 : }
958 :
959 : Driver:
960 0 : if (!callback && dev->driver && dev->driver->pm) {
961 0 : info = "driver ";
962 0 : callback = pm_op(dev->driver->pm, state);
963 : }
964 :
965 : End:
966 0 : error = dpm_run_callback(callback, dev, state, info);
967 0 : dev->power.is_suspended = false;
968 :
969 : Unlock:
970 : device_unlock(dev);
971 : dpm_watchdog_clear(&wd);
972 :
973 : Complete:
974 0 : complete_all(&dev->power.completion);
975 :
976 : TRACE_RESUME(error);
977 :
978 0 : return error;
979 : }
980 :
981 0 : static void async_resume(void *data, async_cookie_t cookie)
982 : {
983 0 : struct device *dev = (struct device *)data;
984 : int error;
985 :
986 0 : error = device_resume(dev, pm_transition, true);
987 0 : if (error)
988 : pm_dev_err(dev, pm_transition, " async", error);
989 0 : put_device(dev);
990 0 : }
991 :
992 : /**
993 : * dpm_resume - Execute "resume" callbacks for non-sysdev devices.
994 : * @state: PM transition of the system being carried out.
995 : *
996 : * Execute the appropriate "resume" callback for all devices whose status
997 : * indicates that they are suspended.
998 : */
999 0 : void dpm_resume(pm_message_t state)
1000 : {
1001 : struct device *dev;
1002 0 : ktime_t starttime = ktime_get();
1003 :
1004 0 : trace_suspend_resume(TPS("dpm_resume"), state.event, true);
1005 : might_sleep();
1006 :
1007 0 : mutex_lock(&dpm_list_mtx);
1008 0 : pm_transition = state;
1009 0 : async_error = 0;
1010 :
1011 0 : list_for_each_entry(dev, &dpm_suspended_list, power.entry)
1012 0 : dpm_async_fn(dev, async_resume);
1013 :
1014 0 : while (!list_empty(&dpm_suspended_list)) {
1015 0 : dev = to_device(dpm_suspended_list.next);
1016 0 : get_device(dev);
1017 0 : if (!is_async(dev)) {
1018 : int error;
1019 :
1020 0 : mutex_unlock(&dpm_list_mtx);
1021 :
1022 0 : error = device_resume(dev, state, false);
1023 0 : if (error) {
1024 0 : suspend_stats.failed_resume++;
1025 0 : dpm_save_failed_step(SUSPEND_RESUME);
1026 0 : dpm_save_failed_dev(dev_name(dev));
1027 : pm_dev_err(dev, state, "", error);
1028 : }
1029 :
1030 0 : mutex_lock(&dpm_list_mtx);
1031 : }
1032 0 : if (!list_empty(&dev->power.entry))
1033 0 : list_move_tail(&dev->power.entry, &dpm_prepared_list);
1034 :
1035 0 : mutex_unlock(&dpm_list_mtx);
1036 :
1037 0 : put_device(dev);
1038 :
1039 0 : mutex_lock(&dpm_list_mtx);
1040 : }
1041 0 : mutex_unlock(&dpm_list_mtx);
1042 0 : async_synchronize_full();
1043 0 : dpm_show_time(starttime, state, 0, NULL);
1044 :
1045 : cpufreq_resume();
1046 : devfreq_resume();
1047 0 : trace_suspend_resume(TPS("dpm_resume"), state.event, false);
1048 0 : }
1049 :
1050 : /**
1051 : * device_complete - Complete a PM transition for given device.
1052 : * @dev: Device to handle.
1053 : * @state: PM transition of the system being carried out.
1054 : */
1055 0 : static void device_complete(struct device *dev, pm_message_t state)
1056 : {
1057 0 : void (*callback)(struct device *) = NULL;
1058 0 : const char *info = NULL;
1059 :
1060 0 : if (dev->power.syscore)
1061 : goto out;
1062 :
1063 0 : device_lock(dev);
1064 :
1065 0 : if (dev->pm_domain) {
1066 0 : info = "completing power domain ";
1067 0 : callback = dev->pm_domain->ops.complete;
1068 0 : } else if (dev->type && dev->type->pm) {
1069 0 : info = "completing type ";
1070 0 : callback = dev->type->pm->complete;
1071 0 : } else if (dev->class && dev->class->pm) {
1072 0 : info = "completing class ";
1073 0 : callback = dev->class->pm->complete;
1074 0 : } else if (dev->bus && dev->bus->pm) {
1075 0 : info = "completing bus ";
1076 0 : callback = dev->bus->pm->complete;
1077 : }
1078 :
1079 0 : if (!callback && dev->driver && dev->driver->pm) {
1080 0 : info = "completing driver ";
1081 0 : callback = dev->driver->pm->complete;
1082 : }
1083 :
1084 0 : if (callback) {
1085 0 : pm_dev_dbg(dev, state, info);
1086 0 : callback(dev);
1087 : }
1088 :
1089 : device_unlock(dev);
1090 :
1091 : out:
1092 0 : pm_runtime_put(dev);
1093 0 : }
1094 :
1095 : /**
1096 : * dpm_complete - Complete a PM transition for all non-sysdev devices.
1097 : * @state: PM transition of the system being carried out.
1098 : *
1099 : * Execute the ->complete() callbacks for all devices whose PM status is not
1100 : * DPM_ON (this allows new devices to be registered).
1101 : */
1102 0 : void dpm_complete(pm_message_t state)
1103 : {
1104 : struct list_head list;
1105 :
1106 0 : trace_suspend_resume(TPS("dpm_complete"), state.event, true);
1107 : might_sleep();
1108 :
1109 0 : INIT_LIST_HEAD(&list);
1110 0 : mutex_lock(&dpm_list_mtx);
1111 0 : while (!list_empty(&dpm_prepared_list)) {
1112 0 : struct device *dev = to_device(dpm_prepared_list.prev);
1113 :
1114 0 : get_device(dev);
1115 0 : dev->power.is_prepared = false;
1116 0 : list_move(&dev->power.entry, &list);
1117 :
1118 0 : mutex_unlock(&dpm_list_mtx);
1119 :
1120 0 : trace_device_pm_callback_start(dev, "", state.event);
1121 0 : device_complete(dev, state);
1122 0 : trace_device_pm_callback_end(dev, 0);
1123 :
1124 0 : put_device(dev);
1125 :
1126 0 : mutex_lock(&dpm_list_mtx);
1127 : }
1128 0 : list_splice(&list, &dpm_list);
1129 0 : mutex_unlock(&dpm_list_mtx);
1130 :
1131 : /* Allow device probing and trigger re-probing of deferred devices */
1132 0 : device_unblock_probing();
1133 0 : trace_suspend_resume(TPS("dpm_complete"), state.event, false);
1134 0 : }
1135 :
1136 : /**
1137 : * dpm_resume_end - Execute "resume" callbacks and complete system transition.
1138 : * @state: PM transition of the system being carried out.
1139 : *
1140 : * Execute "resume" callbacks for all devices and complete the PM transition of
1141 : * the system.
1142 : */
1143 0 : void dpm_resume_end(pm_message_t state)
1144 : {
1145 0 : dpm_resume(state);
1146 0 : dpm_complete(state);
1147 0 : }
1148 : EXPORT_SYMBOL_GPL(dpm_resume_end);
1149 :
1150 :
1151 : /*------------------------- Suspend routines -------------------------*/
1152 :
1153 : /**
1154 : * resume_event - Return a "resume" message for given "suspend" sleep state.
1155 : * @sleep_state: PM message representing a sleep state.
1156 : *
1157 : * Return a PM message representing the resume event corresponding to given
1158 : * sleep state.
1159 : */
1160 : static pm_message_t resume_event(pm_message_t sleep_state)
1161 : {
1162 0 : switch (sleep_state.event) {
1163 : case PM_EVENT_SUSPEND:
1164 : return PMSG_RESUME;
1165 : case PM_EVENT_FREEZE:
1166 : case PM_EVENT_QUIESCE:
1167 : return PMSG_RECOVER;
1168 : case PM_EVENT_HIBERNATE:
1169 : return PMSG_RESTORE;
1170 : }
1171 : return PMSG_ON;
1172 : }
1173 :
1174 0 : static void dpm_superior_set_must_resume(struct device *dev)
1175 : {
1176 : struct device_link *link;
1177 : int idx;
1178 :
1179 0 : if (dev->parent)
1180 0 : dev->parent->power.must_resume = true;
1181 :
1182 0 : idx = device_links_read_lock();
1183 :
1184 0 : list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node)
1185 0 : link->supplier->power.must_resume = true;
1186 :
1187 0 : device_links_read_unlock(idx);
1188 0 : }
1189 :
1190 : /**
1191 : * __device_suspend_noirq - Execute a "noirq suspend" callback for given device.
1192 : * @dev: Device to handle.
1193 : * @state: PM transition of the system being carried out.
1194 : * @async: If true, the device is being suspended asynchronously.
1195 : *
1196 : * The driver of @dev will not receive interrupts while this function is being
1197 : * executed.
1198 : */
1199 0 : static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool async)
1200 : {
1201 0 : pm_callback_t callback = NULL;
1202 0 : const char *info = NULL;
1203 0 : int error = 0;
1204 :
1205 : TRACE_DEVICE(dev);
1206 : TRACE_SUSPEND(0);
1207 :
1208 0 : dpm_wait_for_subordinate(dev, async);
1209 :
1210 0 : if (async_error)
1211 : goto Complete;
1212 :
1213 0 : if (dev->power.syscore || dev->power.direct_complete)
1214 : goto Complete;
1215 :
1216 0 : if (dev->pm_domain) {
1217 0 : info = "noirq power domain ";
1218 0 : callback = pm_noirq_op(&dev->pm_domain->ops, state);
1219 0 : } else if (dev->type && dev->type->pm) {
1220 0 : info = "noirq type ";
1221 0 : callback = pm_noirq_op(dev->type->pm, state);
1222 0 : } else if (dev->class && dev->class->pm) {
1223 0 : info = "noirq class ";
1224 0 : callback = pm_noirq_op(dev->class->pm, state);
1225 0 : } else if (dev->bus && dev->bus->pm) {
1226 0 : info = "noirq bus ";
1227 0 : callback = pm_noirq_op(dev->bus->pm, state);
1228 : }
1229 0 : if (callback)
1230 : goto Run;
1231 :
1232 0 : if (dev_pm_skip_suspend(dev))
1233 : goto Skip;
1234 :
1235 0 : if (dev->driver && dev->driver->pm) {
1236 0 : info = "noirq driver ";
1237 0 : callback = pm_noirq_op(dev->driver->pm, state);
1238 : }
1239 :
1240 : Run:
1241 0 : error = dpm_run_callback(callback, dev, state, info);
1242 0 : if (error) {
1243 0 : async_error = error;
1244 0 : goto Complete;
1245 : }
1246 :
1247 : Skip:
1248 0 : dev->power.is_noirq_suspended = true;
1249 :
1250 : /*
1251 : * Skipping the resume of devices that were in use right before the
1252 : * system suspend (as indicated by their PM-runtime usage counters)
1253 : * would be suboptimal. Also resume them if doing that is not allowed
1254 : * to be skipped.
1255 : */
1256 0 : if (atomic_read(&dev->power.usage_count) > 1 ||
1257 0 : !(dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME) &&
1258 : dev->power.may_skip_resume))
1259 0 : dev->power.must_resume = true;
1260 :
1261 0 : if (dev->power.must_resume)
1262 0 : dpm_superior_set_must_resume(dev);
1263 :
1264 : Complete:
1265 0 : complete_all(&dev->power.completion);
1266 : TRACE_SUSPEND(error);
1267 0 : return error;
1268 : }
1269 :
1270 0 : static void async_suspend_noirq(void *data, async_cookie_t cookie)
1271 : {
1272 0 : struct device *dev = (struct device *)data;
1273 : int error;
1274 :
1275 0 : error = __device_suspend_noirq(dev, pm_transition, true);
1276 0 : if (error) {
1277 0 : dpm_save_failed_dev(dev_name(dev));
1278 : pm_dev_err(dev, pm_transition, " async", error);
1279 : }
1280 :
1281 0 : put_device(dev);
1282 0 : }
1283 :
1284 0 : static int device_suspend_noirq(struct device *dev)
1285 : {
1286 0 : if (dpm_async_fn(dev, async_suspend_noirq))
1287 : return 0;
1288 :
1289 0 : return __device_suspend_noirq(dev, pm_transition, false);
1290 : }
1291 :
1292 0 : static int dpm_noirq_suspend_devices(pm_message_t state)
1293 : {
1294 0 : ktime_t starttime = ktime_get();
1295 0 : int error = 0;
1296 :
1297 0 : trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true);
1298 0 : mutex_lock(&dpm_list_mtx);
1299 0 : pm_transition = state;
1300 0 : async_error = 0;
1301 :
1302 0 : while (!list_empty(&dpm_late_early_list)) {
1303 0 : struct device *dev = to_device(dpm_late_early_list.prev);
1304 :
1305 0 : get_device(dev);
1306 0 : mutex_unlock(&dpm_list_mtx);
1307 :
1308 0 : error = device_suspend_noirq(dev);
1309 :
1310 0 : mutex_lock(&dpm_list_mtx);
1311 :
1312 0 : if (error) {
1313 0 : pm_dev_err(dev, state, " noirq", error);
1314 0 : dpm_save_failed_dev(dev_name(dev));
1315 0 : } else if (!list_empty(&dev->power.entry)) {
1316 0 : list_move(&dev->power.entry, &dpm_noirq_list);
1317 : }
1318 :
1319 0 : mutex_unlock(&dpm_list_mtx);
1320 :
1321 0 : put_device(dev);
1322 :
1323 0 : mutex_lock(&dpm_list_mtx);
1324 :
1325 0 : if (error || async_error)
1326 : break;
1327 : }
1328 0 : mutex_unlock(&dpm_list_mtx);
1329 0 : async_synchronize_full();
1330 0 : if (!error)
1331 0 : error = async_error;
1332 :
1333 0 : if (error) {
1334 0 : suspend_stats.failed_suspend_noirq++;
1335 : dpm_save_failed_step(SUSPEND_SUSPEND_NOIRQ);
1336 : }
1337 0 : dpm_show_time(starttime, state, error, "noirq");
1338 0 : trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, false);
1339 0 : return error;
1340 : }
1341 :
1342 : /**
1343 : * dpm_suspend_noirq - Execute "noirq suspend" callbacks for all devices.
1344 : * @state: PM transition of the system being carried out.
1345 : *
1346 : * Prevent device drivers' interrupt handlers from being called and invoke
1347 : * "noirq" suspend callbacks for all non-sysdev devices.
1348 : */
1349 0 : int dpm_suspend_noirq(pm_message_t state)
1350 : {
1351 : int ret;
1352 :
1353 0 : device_wakeup_arm_wake_irqs();
1354 0 : suspend_device_irqs();
1355 :
1356 0 : ret = dpm_noirq_suspend_devices(state);
1357 0 : if (ret)
1358 : dpm_resume_noirq(resume_event(state));
1359 :
1360 0 : return ret;
1361 : }
1362 :
1363 0 : static void dpm_propagate_wakeup_to_parent(struct device *dev)
1364 : {
1365 0 : struct device *parent = dev->parent;
1366 :
1367 0 : if (!parent)
1368 : return;
1369 :
1370 0 : spin_lock_irq(&parent->power.lock);
1371 :
1372 0 : if (device_wakeup_path(dev) && !parent->power.ignore_children)
1373 0 : parent->power.wakeup_path = true;
1374 :
1375 0 : spin_unlock_irq(&parent->power.lock);
1376 : }
1377 :
1378 : /**
1379 : * __device_suspend_late - Execute a "late suspend" callback for given device.
1380 : * @dev: Device to handle.
1381 : * @state: PM transition of the system being carried out.
1382 : * @async: If true, the device is being suspended asynchronously.
1383 : *
1384 : * Runtime PM is disabled for @dev while this function is being executed.
1385 : */
1386 0 : static int __device_suspend_late(struct device *dev, pm_message_t state, bool async)
1387 : {
1388 0 : pm_callback_t callback = NULL;
1389 0 : const char *info = NULL;
1390 0 : int error = 0;
1391 :
1392 : TRACE_DEVICE(dev);
1393 : TRACE_SUSPEND(0);
1394 :
1395 0 : __pm_runtime_disable(dev, false);
1396 :
1397 0 : dpm_wait_for_subordinate(dev, async);
1398 :
1399 0 : if (async_error)
1400 : goto Complete;
1401 :
1402 0 : if (pm_wakeup_pending()) {
1403 0 : async_error = -EBUSY;
1404 0 : goto Complete;
1405 : }
1406 :
1407 0 : if (dev->power.syscore || dev->power.direct_complete)
1408 : goto Complete;
1409 :
1410 0 : if (dev->pm_domain) {
1411 0 : info = "late power domain ";
1412 0 : callback = pm_late_early_op(&dev->pm_domain->ops, state);
1413 0 : } else if (dev->type && dev->type->pm) {
1414 0 : info = "late type ";
1415 0 : callback = pm_late_early_op(dev->type->pm, state);
1416 0 : } else if (dev->class && dev->class->pm) {
1417 0 : info = "late class ";
1418 0 : callback = pm_late_early_op(dev->class->pm, state);
1419 0 : } else if (dev->bus && dev->bus->pm) {
1420 0 : info = "late bus ";
1421 0 : callback = pm_late_early_op(dev->bus->pm, state);
1422 : }
1423 0 : if (callback)
1424 : goto Run;
1425 :
1426 0 : if (dev_pm_skip_suspend(dev))
1427 : goto Skip;
1428 :
1429 0 : if (dev->driver && dev->driver->pm) {
1430 0 : info = "late driver ";
1431 0 : callback = pm_late_early_op(dev->driver->pm, state);
1432 : }
1433 :
1434 : Run:
1435 0 : error = dpm_run_callback(callback, dev, state, info);
1436 0 : if (error) {
1437 0 : async_error = error;
1438 0 : goto Complete;
1439 : }
1440 0 : dpm_propagate_wakeup_to_parent(dev);
1441 :
1442 : Skip:
1443 0 : dev->power.is_late_suspended = true;
1444 :
1445 : Complete:
1446 : TRACE_SUSPEND(error);
1447 0 : complete_all(&dev->power.completion);
1448 0 : return error;
1449 : }
1450 :
1451 0 : static void async_suspend_late(void *data, async_cookie_t cookie)
1452 : {
1453 0 : struct device *dev = (struct device *)data;
1454 : int error;
1455 :
1456 0 : error = __device_suspend_late(dev, pm_transition, true);
1457 0 : if (error) {
1458 0 : dpm_save_failed_dev(dev_name(dev));
1459 : pm_dev_err(dev, pm_transition, " async", error);
1460 : }
1461 0 : put_device(dev);
1462 0 : }
1463 :
1464 0 : static int device_suspend_late(struct device *dev)
1465 : {
1466 0 : if (dpm_async_fn(dev, async_suspend_late))
1467 : return 0;
1468 :
1469 0 : return __device_suspend_late(dev, pm_transition, false);
1470 : }
1471 :
1472 : /**
1473 : * dpm_suspend_late - Execute "late suspend" callbacks for all devices.
1474 : * @state: PM transition of the system being carried out.
1475 : */
1476 0 : int dpm_suspend_late(pm_message_t state)
1477 : {
1478 0 : ktime_t starttime = ktime_get();
1479 0 : int error = 0;
1480 :
1481 0 : trace_suspend_resume(TPS("dpm_suspend_late"), state.event, true);
1482 : wake_up_all_idle_cpus();
1483 0 : mutex_lock(&dpm_list_mtx);
1484 0 : pm_transition = state;
1485 0 : async_error = 0;
1486 :
1487 0 : while (!list_empty(&dpm_suspended_list)) {
1488 0 : struct device *dev = to_device(dpm_suspended_list.prev);
1489 :
1490 0 : get_device(dev);
1491 :
1492 0 : mutex_unlock(&dpm_list_mtx);
1493 :
1494 0 : error = device_suspend_late(dev);
1495 :
1496 0 : mutex_lock(&dpm_list_mtx);
1497 :
1498 0 : if (!list_empty(&dev->power.entry))
1499 0 : list_move(&dev->power.entry, &dpm_late_early_list);
1500 :
1501 0 : if (error) {
1502 0 : pm_dev_err(dev, state, " late", error);
1503 0 : dpm_save_failed_dev(dev_name(dev));
1504 : }
1505 :
1506 0 : mutex_unlock(&dpm_list_mtx);
1507 :
1508 0 : put_device(dev);
1509 :
1510 0 : mutex_lock(&dpm_list_mtx);
1511 :
1512 0 : if (error || async_error)
1513 : break;
1514 : }
1515 0 : mutex_unlock(&dpm_list_mtx);
1516 0 : async_synchronize_full();
1517 0 : if (!error)
1518 0 : error = async_error;
1519 0 : if (error) {
1520 0 : suspend_stats.failed_suspend_late++;
1521 0 : dpm_save_failed_step(SUSPEND_SUSPEND_LATE);
1522 0 : dpm_resume_early(resume_event(state));
1523 : }
1524 0 : dpm_show_time(starttime, state, error, "late");
1525 0 : trace_suspend_resume(TPS("dpm_suspend_late"), state.event, false);
1526 0 : return error;
1527 : }
1528 :
1529 : /**
1530 : * dpm_suspend_end - Execute "late" and "noirq" device suspend callbacks.
1531 : * @state: PM transition of the system being carried out.
1532 : */
1533 0 : int dpm_suspend_end(pm_message_t state)
1534 : {
1535 0 : ktime_t starttime = ktime_get();
1536 : int error;
1537 :
1538 0 : error = dpm_suspend_late(state);
1539 0 : if (error)
1540 : goto out;
1541 :
1542 0 : error = dpm_suspend_noirq(state);
1543 0 : if (error)
1544 0 : dpm_resume_early(resume_event(state));
1545 :
1546 : out:
1547 0 : dpm_show_time(starttime, state, error, "end");
1548 0 : return error;
1549 : }
1550 : EXPORT_SYMBOL_GPL(dpm_suspend_end);
1551 :
1552 : /**
1553 : * legacy_suspend - Execute a legacy (bus or class) suspend callback for device.
1554 : * @dev: Device to suspend.
1555 : * @state: PM transition of the system being carried out.
1556 : * @cb: Suspend callback to execute.
1557 : * @info: string description of caller.
1558 : */
1559 0 : static int legacy_suspend(struct device *dev, pm_message_t state,
1560 : int (*cb)(struct device *dev, pm_message_t state),
1561 : const char *info)
1562 : {
1563 : int error;
1564 : ktime_t calltime;
1565 :
1566 0 : calltime = initcall_debug_start(dev, cb);
1567 :
1568 0 : trace_device_pm_callback_start(dev, info, state.event);
1569 0 : error = cb(dev, state);
1570 0 : trace_device_pm_callback_end(dev, error);
1571 0 : suspend_report_result(dev, cb, error);
1572 :
1573 0 : initcall_debug_report(dev, calltime, cb, error);
1574 :
1575 0 : return error;
1576 : }
1577 :
1578 0 : static void dpm_clear_superiors_direct_complete(struct device *dev)
1579 : {
1580 : struct device_link *link;
1581 : int idx;
1582 :
1583 0 : if (dev->parent) {
1584 0 : spin_lock_irq(&dev->parent->power.lock);
1585 0 : dev->parent->power.direct_complete = false;
1586 0 : spin_unlock_irq(&dev->parent->power.lock);
1587 : }
1588 :
1589 0 : idx = device_links_read_lock();
1590 :
1591 0 : list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) {
1592 0 : spin_lock_irq(&link->supplier->power.lock);
1593 0 : link->supplier->power.direct_complete = false;
1594 0 : spin_unlock_irq(&link->supplier->power.lock);
1595 : }
1596 :
1597 0 : device_links_read_unlock(idx);
1598 0 : }
1599 :
1600 : /**
1601 : * __device_suspend - Execute "suspend" callbacks for given device.
1602 : * @dev: Device to handle.
1603 : * @state: PM transition of the system being carried out.
1604 : * @async: If true, the device is being suspended asynchronously.
1605 : */
1606 0 : static int __device_suspend(struct device *dev, pm_message_t state, bool async)
1607 : {
1608 0 : pm_callback_t callback = NULL;
1609 0 : const char *info = NULL;
1610 0 : int error = 0;
1611 : DECLARE_DPM_WATCHDOG_ON_STACK(wd);
1612 :
1613 : TRACE_DEVICE(dev);
1614 : TRACE_SUSPEND(0);
1615 :
1616 0 : dpm_wait_for_subordinate(dev, async);
1617 :
1618 0 : if (async_error) {
1619 0 : dev->power.direct_complete = false;
1620 0 : goto Complete;
1621 : }
1622 :
1623 : /*
1624 : * Wait for possible runtime PM transitions of the device in progress
1625 : * to complete and if there's a runtime resume request pending for it,
1626 : * resume it before proceeding with invoking the system-wide suspend
1627 : * callbacks for it.
1628 : *
1629 : * If the system-wide suspend callbacks below change the configuration
1630 : * of the device, they must disable runtime PM for it or otherwise
1631 : * ensure that its runtime-resume callbacks will not be confused by that
1632 : * change in case they are invoked going forward.
1633 : */
1634 0 : pm_runtime_barrier(dev);
1635 :
1636 0 : if (pm_wakeup_pending()) {
1637 0 : dev->power.direct_complete = false;
1638 0 : async_error = -EBUSY;
1639 0 : goto Complete;
1640 : }
1641 :
1642 0 : if (dev->power.syscore)
1643 : goto Complete;
1644 :
1645 : /* Avoid direct_complete to let wakeup_path propagate. */
1646 0 : if (device_may_wakeup(dev) || device_wakeup_path(dev))
1647 0 : dev->power.direct_complete = false;
1648 :
1649 0 : if (dev->power.direct_complete) {
1650 0 : if (pm_runtime_status_suspended(dev)) {
1651 0 : pm_runtime_disable(dev);
1652 0 : if (pm_runtime_status_suspended(dev)) {
1653 : pm_dev_dbg(dev, state, "direct-complete ");
1654 : goto Complete;
1655 : }
1656 :
1657 0 : pm_runtime_enable(dev);
1658 : }
1659 0 : dev->power.direct_complete = false;
1660 : }
1661 :
1662 0 : dev->power.may_skip_resume = true;
1663 0 : dev->power.must_resume = !dev_pm_test_driver_flags(dev, DPM_FLAG_MAY_SKIP_RESUME);
1664 :
1665 : dpm_watchdog_set(&wd, dev);
1666 0 : device_lock(dev);
1667 :
1668 0 : if (dev->pm_domain) {
1669 0 : info = "power domain ";
1670 0 : callback = pm_op(&dev->pm_domain->ops, state);
1671 : goto Run;
1672 : }
1673 :
1674 0 : if (dev->type && dev->type->pm) {
1675 0 : info = "type ";
1676 0 : callback = pm_op(dev->type->pm, state);
1677 : goto Run;
1678 : }
1679 :
1680 0 : if (dev->class && dev->class->pm) {
1681 0 : info = "class ";
1682 0 : callback = pm_op(dev->class->pm, state);
1683 : goto Run;
1684 : }
1685 :
1686 0 : if (dev->bus) {
1687 0 : if (dev->bus->pm) {
1688 0 : info = "bus ";
1689 0 : callback = pm_op(dev->bus->pm, state);
1690 0 : } else if (dev->bus->suspend) {
1691 0 : pm_dev_dbg(dev, state, "legacy bus ");
1692 0 : error = legacy_suspend(dev, state, dev->bus->suspend,
1693 : "legacy bus ");
1694 0 : goto End;
1695 : }
1696 : }
1697 :
1698 : Run:
1699 0 : if (!callback && dev->driver && dev->driver->pm) {
1700 0 : info = "driver ";
1701 0 : callback = pm_op(dev->driver->pm, state);
1702 : }
1703 :
1704 0 : error = dpm_run_callback(callback, dev, state, info);
1705 :
1706 : End:
1707 0 : if (!error) {
1708 0 : dev->power.is_suspended = true;
1709 0 : if (device_may_wakeup(dev))
1710 0 : dev->power.wakeup_path = true;
1711 :
1712 0 : dpm_propagate_wakeup_to_parent(dev);
1713 0 : dpm_clear_superiors_direct_complete(dev);
1714 : }
1715 :
1716 : device_unlock(dev);
1717 : dpm_watchdog_clear(&wd);
1718 :
1719 : Complete:
1720 0 : if (error)
1721 0 : async_error = error;
1722 :
1723 0 : complete_all(&dev->power.completion);
1724 : TRACE_SUSPEND(error);
1725 0 : return error;
1726 : }
1727 :
1728 0 : static void async_suspend(void *data, async_cookie_t cookie)
1729 : {
1730 0 : struct device *dev = (struct device *)data;
1731 : int error;
1732 :
1733 0 : error = __device_suspend(dev, pm_transition, true);
1734 0 : if (error) {
1735 0 : dpm_save_failed_dev(dev_name(dev));
1736 : pm_dev_err(dev, pm_transition, " async", error);
1737 : }
1738 :
1739 0 : put_device(dev);
1740 0 : }
1741 :
1742 0 : static int device_suspend(struct device *dev)
1743 : {
1744 0 : if (dpm_async_fn(dev, async_suspend))
1745 : return 0;
1746 :
1747 0 : return __device_suspend(dev, pm_transition, false);
1748 : }
1749 :
1750 : /**
1751 : * dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
1752 : * @state: PM transition of the system being carried out.
1753 : */
1754 0 : int dpm_suspend(pm_message_t state)
1755 : {
1756 0 : ktime_t starttime = ktime_get();
1757 0 : int error = 0;
1758 :
1759 0 : trace_suspend_resume(TPS("dpm_suspend"), state.event, true);
1760 : might_sleep();
1761 :
1762 : devfreq_suspend();
1763 : cpufreq_suspend();
1764 :
1765 0 : mutex_lock(&dpm_list_mtx);
1766 0 : pm_transition = state;
1767 0 : async_error = 0;
1768 0 : while (!list_empty(&dpm_prepared_list)) {
1769 0 : struct device *dev = to_device(dpm_prepared_list.prev);
1770 :
1771 0 : get_device(dev);
1772 :
1773 0 : mutex_unlock(&dpm_list_mtx);
1774 :
1775 0 : error = device_suspend(dev);
1776 :
1777 0 : mutex_lock(&dpm_list_mtx);
1778 :
1779 0 : if (error) {
1780 0 : pm_dev_err(dev, state, "", error);
1781 0 : dpm_save_failed_dev(dev_name(dev));
1782 0 : } else if (!list_empty(&dev->power.entry)) {
1783 0 : list_move(&dev->power.entry, &dpm_suspended_list);
1784 : }
1785 :
1786 0 : mutex_unlock(&dpm_list_mtx);
1787 :
1788 0 : put_device(dev);
1789 :
1790 0 : mutex_lock(&dpm_list_mtx);
1791 :
1792 0 : if (error || async_error)
1793 : break;
1794 : }
1795 0 : mutex_unlock(&dpm_list_mtx);
1796 0 : async_synchronize_full();
1797 0 : if (!error)
1798 0 : error = async_error;
1799 0 : if (error) {
1800 0 : suspend_stats.failed_suspend++;
1801 : dpm_save_failed_step(SUSPEND_SUSPEND);
1802 : }
1803 0 : dpm_show_time(starttime, state, error, NULL);
1804 0 : trace_suspend_resume(TPS("dpm_suspend"), state.event, false);
1805 0 : return error;
1806 : }
1807 :
1808 : /**
1809 : * device_prepare - Prepare a device for system power transition.
1810 : * @dev: Device to handle.
1811 : * @state: PM transition of the system being carried out.
1812 : *
1813 : * Execute the ->prepare() callback(s) for given device. No new children of the
1814 : * device may be registered after this function has returned.
1815 : */
1816 0 : static int device_prepare(struct device *dev, pm_message_t state)
1817 : {
1818 0 : int (*callback)(struct device *) = NULL;
1819 0 : int ret = 0;
1820 :
1821 : /*
1822 : * If a device's parent goes into runtime suspend at the wrong time,
1823 : * it won't be possible to resume the device. To prevent this we
1824 : * block runtime suspend here, during the prepare phase, and allow
1825 : * it again during the complete phase.
1826 : */
1827 0 : pm_runtime_get_noresume(dev);
1828 :
1829 0 : if (dev->power.syscore)
1830 : return 0;
1831 :
1832 0 : device_lock(dev);
1833 :
1834 0 : dev->power.wakeup_path = false;
1835 :
1836 0 : if (dev->power.no_pm_callbacks)
1837 : goto unlock;
1838 :
1839 0 : if (dev->pm_domain)
1840 0 : callback = dev->pm_domain->ops.prepare;
1841 0 : else if (dev->type && dev->type->pm)
1842 0 : callback = dev->type->pm->prepare;
1843 0 : else if (dev->class && dev->class->pm)
1844 0 : callback = dev->class->pm->prepare;
1845 0 : else if (dev->bus && dev->bus->pm)
1846 0 : callback = dev->bus->pm->prepare;
1847 :
1848 0 : if (!callback && dev->driver && dev->driver->pm)
1849 0 : callback = dev->driver->pm->prepare;
1850 :
1851 0 : if (callback)
1852 0 : ret = callback(dev);
1853 :
1854 : unlock:
1855 0 : device_unlock(dev);
1856 :
1857 0 : if (ret < 0) {
1858 0 : suspend_report_result(dev, callback, ret);
1859 0 : pm_runtime_put(dev);
1860 0 : return ret;
1861 : }
1862 : /*
1863 : * A positive return value from ->prepare() means "this device appears
1864 : * to be runtime-suspended and its state is fine, so if it really is
1865 : * runtime-suspended, you can leave it in that state provided that you
1866 : * will do the same thing with all of its descendants". This only
1867 : * applies to suspend transitions, however.
1868 : */
1869 0 : spin_lock_irq(&dev->power.lock);
1870 0 : dev->power.direct_complete = state.event == PM_EVENT_SUSPEND &&
1871 0 : (ret > 0 || dev->power.no_pm_callbacks) &&
1872 0 : !dev_pm_test_driver_flags(dev, DPM_FLAG_NO_DIRECT_COMPLETE);
1873 0 : spin_unlock_irq(&dev->power.lock);
1874 0 : return 0;
1875 : }
1876 :
1877 : /**
1878 : * dpm_prepare - Prepare all non-sysdev devices for a system PM transition.
1879 : * @state: PM transition of the system being carried out.
1880 : *
1881 : * Execute the ->prepare() callback(s) for all devices.
1882 : */
1883 0 : int dpm_prepare(pm_message_t state)
1884 : {
1885 0 : int error = 0;
1886 :
1887 0 : trace_suspend_resume(TPS("dpm_prepare"), state.event, true);
1888 : might_sleep();
1889 :
1890 : /*
1891 : * Give a chance for the known devices to complete their probes, before
1892 : * disable probing of devices. This sync point is important at least
1893 : * at boot time + hibernation restore.
1894 : */
1895 0 : wait_for_device_probe();
1896 : /*
1897 : * It is unsafe if probing of devices will happen during suspend or
1898 : * hibernation and system behavior will be unpredictable in this case.
1899 : * So, let's prohibit device's probing here and defer their probes
1900 : * instead. The normal behavior will be restored in dpm_complete().
1901 : */
1902 0 : device_block_probing();
1903 :
1904 0 : mutex_lock(&dpm_list_mtx);
1905 0 : while (!list_empty(&dpm_list) && !error) {
1906 0 : struct device *dev = to_device(dpm_list.next);
1907 :
1908 0 : get_device(dev);
1909 :
1910 0 : mutex_unlock(&dpm_list_mtx);
1911 :
1912 0 : trace_device_pm_callback_start(dev, "", state.event);
1913 0 : error = device_prepare(dev, state);
1914 0 : trace_device_pm_callback_end(dev, error);
1915 :
1916 0 : mutex_lock(&dpm_list_mtx);
1917 :
1918 0 : if (!error) {
1919 0 : dev->power.is_prepared = true;
1920 0 : if (!list_empty(&dev->power.entry))
1921 0 : list_move_tail(&dev->power.entry, &dpm_prepared_list);
1922 0 : } else if (error == -EAGAIN) {
1923 : error = 0;
1924 : } else {
1925 0 : dev_info(dev, "not prepared for power transition: code %d\n",
1926 : error);
1927 : }
1928 :
1929 0 : mutex_unlock(&dpm_list_mtx);
1930 :
1931 0 : put_device(dev);
1932 :
1933 0 : mutex_lock(&dpm_list_mtx);
1934 : }
1935 0 : mutex_unlock(&dpm_list_mtx);
1936 0 : trace_suspend_resume(TPS("dpm_prepare"), state.event, false);
1937 0 : return error;
1938 : }
1939 :
1940 : /**
1941 : * dpm_suspend_start - Prepare devices for PM transition and suspend them.
1942 : * @state: PM transition of the system being carried out.
1943 : *
1944 : * Prepare all non-sysdev devices for system PM transition and execute "suspend"
1945 : * callbacks for them.
1946 : */
1947 0 : int dpm_suspend_start(pm_message_t state)
1948 : {
1949 0 : ktime_t starttime = ktime_get();
1950 : int error;
1951 :
1952 0 : error = dpm_prepare(state);
1953 0 : if (error) {
1954 0 : suspend_stats.failed_prepare++;
1955 : dpm_save_failed_step(SUSPEND_PREPARE);
1956 : } else
1957 0 : error = dpm_suspend(state);
1958 0 : dpm_show_time(starttime, state, error, "start");
1959 0 : return error;
1960 : }
1961 : EXPORT_SYMBOL_GPL(dpm_suspend_start);
1962 :
1963 0 : void __suspend_report_result(const char *function, struct device *dev, void *fn, int ret)
1964 : {
1965 0 : if (ret)
1966 0 : dev_err(dev, "%s(): %pS returns %d\n", function, fn, ret);
1967 0 : }
1968 : EXPORT_SYMBOL_GPL(__suspend_report_result);
1969 :
1970 : /**
1971 : * device_pm_wait_for_dev - Wait for suspend/resume of a device to complete.
1972 : * @subordinate: Device that needs to wait for @dev.
1973 : * @dev: Device to wait for.
1974 : */
1975 0 : int device_pm_wait_for_dev(struct device *subordinate, struct device *dev)
1976 : {
1977 0 : dpm_wait(dev, subordinate->power.async_suspend);
1978 0 : return async_error;
1979 : }
1980 : EXPORT_SYMBOL_GPL(device_pm_wait_for_dev);
1981 :
1982 : /**
1983 : * dpm_for_each_dev - device iterator.
1984 : * @data: data for the callback.
1985 : * @fn: function to be called for each device.
1986 : *
1987 : * Iterate over devices in dpm_list, and call @fn for each device,
1988 : * passing it @data.
1989 : */
1990 0 : void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
1991 : {
1992 : struct device *dev;
1993 :
1994 0 : if (!fn)
1995 : return;
1996 :
1997 : device_pm_lock();
1998 0 : list_for_each_entry(dev, &dpm_list, power.entry)
1999 0 : fn(dev, data);
2000 : device_pm_unlock();
2001 : }
2002 : EXPORT_SYMBOL_GPL(dpm_for_each_dev);
2003 :
2004 602 : static bool pm_ops_is_empty(const struct dev_pm_ops *ops)
2005 : {
2006 602 : if (!ops)
2007 : return true;
2008 :
2009 136 : return !ops->prepare &&
2010 68 : !ops->suspend &&
2011 0 : !ops->suspend_late &&
2012 0 : !ops->suspend_noirq &&
2013 0 : !ops->resume_noirq &&
2014 0 : !ops->resume_early &&
2015 68 : !ops->resume &&
2016 0 : !ops->complete;
2017 : }
2018 :
2019 606 : void device_pm_check_callbacks(struct device *dev)
2020 : {
2021 : unsigned long flags;
2022 :
2023 606 : spin_lock_irqsave(&dev->power.lock, flags);
2024 606 : dev->power.no_pm_callbacks =
2025 682 : (!dev->bus || (pm_ops_is_empty(dev->bus->pm) &&
2026 546 : !dev->bus->suspend && !dev->bus->resume)) &&
2027 1604 : (!dev->class || pm_ops_is_empty(dev->class->pm)) &&
2028 1078 : (!dev->type || pm_ops_is_empty(dev->type->pm)) &&
2029 2288 : (!dev->pm_domain || pm_ops_is_empty(&dev->pm_domain->ops)) &&
2030 538 : (!dev->driver || (pm_ops_is_empty(dev->driver->pm) &&
2031 0 : !dev->driver->suspend && !dev->driver->resume));
2032 1212 : spin_unlock_irqrestore(&dev->power.lock, flags);
2033 606 : }
2034 :
2035 0 : bool dev_pm_skip_suspend(struct device *dev)
2036 : {
2037 0 : return dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) &&
2038 0 : pm_runtime_status_suspended(dev);
2039 : }
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