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1/*
2 * drivers/base/power/domain.c - Common code related to device power domains.
3 *
4 * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
5 *
6 * This file is released under the GPLv2.
7 */
8
9#include <linux/delay.h>
10#include <linux/kernel.h>
11#include <linux/io.h>
12#include <linux/platform_device.h>
13#include <linux/pm_runtime.h>
14#include <linux/pm_domain.h>
15#include <linux/pm_qos.h>
16#include <linux/pm_clock.h>
17#include <linux/slab.h>
18#include <linux/err.h>
19#include <linux/sched.h>
20#include <linux/suspend.h>
21#include <linux/export.h>
22
23#include "power.h"
24
25#define GENPD_RETRY_MAX_MS 250 /* Approximate */
26
27#define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \
28({ \
29 type (*__routine)(struct device *__d); \
30 type __ret = (type)0; \
31 \
32 __routine = genpd->dev_ops.callback; \
33 if (__routine) { \
34 __ret = __routine(dev); \
35 } \
36 __ret; \
37})
38
39static LIST_HEAD(gpd_list);
40static DEFINE_MUTEX(gpd_list_lock);
41
42/*
43 * Get the generic PM domain for a particular struct device.
44 * This validates the struct device pointer, the PM domain pointer,
45 * and checks that the PM domain pointer is a real generic PM domain.
46 * Any failure results in NULL being returned.
47 */
48struct generic_pm_domain *pm_genpd_lookup_dev(struct device *dev)
49{
50 struct generic_pm_domain *genpd = NULL, *gpd;
51
52 if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
53 return NULL;
54
55 mutex_lock(&gpd_list_lock);
56 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
57 if (&gpd->domain == dev->pm_domain) {
58 genpd = gpd;
59 break;
60 }
61 }
62 mutex_unlock(&gpd_list_lock);
63
64 return genpd;
65}
66
67/*
68 * This should only be used where we are certain that the pm_domain
69 * attached to the device is a genpd domain.
70 */
71static struct generic_pm_domain *dev_to_genpd(struct device *dev)
72{
73 if (IS_ERR_OR_NULL(dev->pm_domain))
74 return ERR_PTR(-EINVAL);
75
76 return pd_to_genpd(dev->pm_domain);
77}
78
79static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
80{
81 return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
82}
83
84static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
85{
86 return GENPD_DEV_CALLBACK(genpd, int, start, dev);
87}
88
89static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
90{
91 bool ret = false;
92
93 if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
94 ret = !!atomic_dec_and_test(&genpd->sd_count);
95
96 return ret;
97}
98
99static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
100{
101 atomic_inc(&genpd->sd_count);
102 smp_mb__after_atomic();
103}
104
105static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
106{
107 unsigned int state_idx = genpd->state_idx;
108 ktime_t time_start;
109 s64 elapsed_ns;
110 int ret;
111
112 if (!genpd->power_on)
113 return 0;
114
115 if (!timed)
116 return genpd->power_on(genpd);
117
118 time_start = ktime_get();
119 ret = genpd->power_on(genpd);
120 if (ret)
121 return ret;
122
123 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
124 if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
125 return ret;
126
127 genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
128 genpd->max_off_time_changed = true;
129 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
130 genpd->name, "on", elapsed_ns);
131
132 return ret;
133}
134
135static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
136{
137 unsigned int state_idx = genpd->state_idx;
138 ktime_t time_start;
139 s64 elapsed_ns;
140 int ret;
141
142 if (!genpd->power_off)
143 return 0;
144
145 if (!timed)
146 return genpd->power_off(genpd);
147
148 time_start = ktime_get();
149 ret = genpd->power_off(genpd);
150 if (ret == -EBUSY)
151 return ret;
152
153 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
154 if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns)
155 return ret;
156
157 genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
158 genpd->max_off_time_changed = true;
159 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
160 genpd->name, "off", elapsed_ns);
161
162 return ret;
163}
164
165/**
166 * genpd_queue_power_off_work - Queue up the execution of genpd_poweroff().
167 * @genpd: PM domain to power off.
168 *
169 * Queue up the execution of genpd_poweroff() unless it's already been done
170 * before.
171 */
172static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
173{
174 queue_work(pm_wq, &genpd->power_off_work);
175}
176
177/**
178 * genpd_poweron - Restore power to a given PM domain and its masters.
179 * @genpd: PM domain to power up.
180 * @depth: nesting count for lockdep.
181 *
182 * Restore power to @genpd and all of its masters so that it is possible to
183 * resume a device belonging to it.
184 */
185static int genpd_poweron(struct generic_pm_domain *genpd, unsigned int depth)
186{
187 struct gpd_link *link;
188 int ret = 0;
189
190 if (genpd->status == GPD_STATE_ACTIVE
191 || (genpd->prepared_count > 0 && genpd->suspend_power_off))
192 return 0;
193
194 /*
195 * The list is guaranteed not to change while the loop below is being
196 * executed, unless one of the masters' .power_on() callbacks fiddles
197 * with it.
198 */
199 list_for_each_entry(link, &genpd->slave_links, slave_node) {
200 struct generic_pm_domain *master = link->master;
201
202 genpd_sd_counter_inc(master);
203
204 mutex_lock_nested(&master->lock, depth + 1);
205 ret = genpd_poweron(master, depth + 1);
206 mutex_unlock(&master->lock);
207
208 if (ret) {
209 genpd_sd_counter_dec(master);
210 goto err;
211 }
212 }
213
214 ret = genpd_power_on(genpd, true);
215 if (ret)
216 goto err;
217
218 genpd->status = GPD_STATE_ACTIVE;
219 return 0;
220
221 err:
222 list_for_each_entry_continue_reverse(link,
223 &genpd->slave_links,
224 slave_node) {
225 genpd_sd_counter_dec(link->master);
226 genpd_queue_power_off_work(link->master);
227 }
228
229 return ret;
230}
231
232static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
233{
234 return GENPD_DEV_CALLBACK(genpd, int, save_state, dev);
235}
236
237static int genpd_restore_dev(struct generic_pm_domain *genpd,
238 struct device *dev)
239{
240 return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev);
241}
242
243static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
244 unsigned long val, void *ptr)
245{
246 struct generic_pm_domain_data *gpd_data;
247 struct device *dev;
248
249 gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
250 dev = gpd_data->base.dev;
251
252 for (;;) {
253 struct generic_pm_domain *genpd;
254 struct pm_domain_data *pdd;
255
256 spin_lock_irq(&dev->power.lock);
257
258 pdd = dev->power.subsys_data ?
259 dev->power.subsys_data->domain_data : NULL;
260 if (pdd && pdd->dev) {
261 to_gpd_data(pdd)->td.constraint_changed = true;
262 genpd = dev_to_genpd(dev);
263 } else {
264 genpd = ERR_PTR(-ENODATA);
265 }
266
267 spin_unlock_irq(&dev->power.lock);
268
269 if (!IS_ERR(genpd)) {
270 mutex_lock(&genpd->lock);
271 genpd->max_off_time_changed = true;
272 mutex_unlock(&genpd->lock);
273 }
274
275 dev = dev->parent;
276 if (!dev || dev->power.ignore_children)
277 break;
278 }
279
280 return NOTIFY_DONE;
281}
282
283/**
284 * genpd_poweroff - Remove power from a given PM domain.
285 * @genpd: PM domain to power down.
286 * @is_async: PM domain is powered down from a scheduled work
287 *
288 * If all of the @genpd's devices have been suspended and all of its subdomains
289 * have been powered down, remove power from @genpd.
290 */
291static int genpd_poweroff(struct generic_pm_domain *genpd, bool is_async)
292{
293 struct pm_domain_data *pdd;
294 struct gpd_link *link;
295 unsigned int not_suspended = 0;
296
297 /*
298 * Do not try to power off the domain in the following situations:
299 * (1) The domain is already in the "power off" state.
300 * (2) System suspend is in progress.
301 */
302 if (genpd->status == GPD_STATE_POWER_OFF
303 || genpd->prepared_count > 0)
304 return 0;
305
306 if (atomic_read(&genpd->sd_count) > 0)
307 return -EBUSY;
308
309 list_for_each_entry(pdd, &genpd->dev_list, list_node) {
310 enum pm_qos_flags_status stat;
311
312 stat = dev_pm_qos_flags(pdd->dev,
313 PM_QOS_FLAG_NO_POWER_OFF
314 | PM_QOS_FLAG_REMOTE_WAKEUP);
315 if (stat > PM_QOS_FLAGS_NONE)
316 return -EBUSY;
317
318 if (!pm_runtime_suspended(pdd->dev) || pdd->dev->power.irq_safe)
319 not_suspended++;
320 }
321
322 if (not_suspended > 1 || (not_suspended == 1 && is_async))
323 return -EBUSY;
324
325 if (genpd->gov && genpd->gov->power_down_ok) {
326 if (!genpd->gov->power_down_ok(&genpd->domain))
327 return -EAGAIN;
328 }
329
330 if (genpd->power_off) {
331 int ret;
332
333 if (atomic_read(&genpd->sd_count) > 0)
334 return -EBUSY;
335
336 /*
337 * If sd_count > 0 at this point, one of the subdomains hasn't
338 * managed to call genpd_poweron() for the master yet after
339 * incrementing it. In that case genpd_poweron() will wait
340 * for us to drop the lock, so we can call .power_off() and let
341 * the genpd_poweron() restore power for us (this shouldn't
342 * happen very often).
343 */
344 ret = genpd_power_off(genpd, true);
345 if (ret)
346 return ret;
347 }
348
349 genpd->status = GPD_STATE_POWER_OFF;
350
351 list_for_each_entry(link, &genpd->slave_links, slave_node) {
352 genpd_sd_counter_dec(link->master);
353 genpd_queue_power_off_work(link->master);
354 }
355
356 return 0;
357}
358
359/**
360 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
361 * @work: Work structure used for scheduling the execution of this function.
362 */
363static void genpd_power_off_work_fn(struct work_struct *work)
364{
365 struct generic_pm_domain *genpd;
366
367 genpd = container_of(work, struct generic_pm_domain, power_off_work);
368
369 mutex_lock(&genpd->lock);
370 genpd_poweroff(genpd, true);
371 mutex_unlock(&genpd->lock);
372}
373
374/**
375 * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
376 * @dev: Device to suspend.
377 *
378 * Carry out a runtime suspend of a device under the assumption that its
379 * pm_domain field points to the domain member of an object of type
380 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
381 */
382static int pm_genpd_runtime_suspend(struct device *dev)
383{
384 struct generic_pm_domain *genpd;
385 bool (*stop_ok)(struct device *__dev);
386 struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
387 bool runtime_pm = pm_runtime_enabled(dev);
388 ktime_t time_start;
389 s64 elapsed_ns;
390 int ret;
391
392 dev_dbg(dev, "%s()\n", __func__);
393
394 genpd = dev_to_genpd(dev);
395 if (IS_ERR(genpd))
396 return -EINVAL;
397
398 /*
399 * A runtime PM centric subsystem/driver may re-use the runtime PM
400 * callbacks for other purposes than runtime PM. In those scenarios
401 * runtime PM is disabled. Under these circumstances, we shall skip
402 * validating/measuring the PM QoS latency.
403 */
404 stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
405 if (runtime_pm && stop_ok && !stop_ok(dev))
406 return -EBUSY;
407
408 /* Measure suspend latency. */
409 if (runtime_pm)
410 time_start = ktime_get();
411
412 ret = genpd_save_dev(genpd, dev);
413 if (ret)
414 return ret;
415
416 ret = genpd_stop_dev(genpd, dev);
417 if (ret) {
418 genpd_restore_dev(genpd, dev);
419 return ret;
420 }
421
422 /* Update suspend latency value if the measured time exceeds it. */
423 if (runtime_pm) {
424 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
425 if (elapsed_ns > td->suspend_latency_ns) {
426 td->suspend_latency_ns = elapsed_ns;
427 dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
428 elapsed_ns);
429 genpd->max_off_time_changed = true;
430 td->constraint_changed = true;
431 }
432 }
433
434 /*
435 * If power.irq_safe is set, this routine will be run with interrupts
436 * off, so it can't use mutexes.
437 */
438 if (dev->power.irq_safe)
439 return 0;
440
441 mutex_lock(&genpd->lock);
442 genpd_poweroff(genpd, false);
443 mutex_unlock(&genpd->lock);
444
445 return 0;
446}
447
448/**
449 * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
450 * @dev: Device to resume.
451 *
452 * Carry out a runtime resume of a device under the assumption that its
453 * pm_domain field points to the domain member of an object of type
454 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
455 */
456static int pm_genpd_runtime_resume(struct device *dev)
457{
458 struct generic_pm_domain *genpd;
459 struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
460 bool runtime_pm = pm_runtime_enabled(dev);
461 ktime_t time_start;
462 s64 elapsed_ns;
463 int ret;
464 bool timed = true;
465
466 dev_dbg(dev, "%s()\n", __func__);
467
468 genpd = dev_to_genpd(dev);
469 if (IS_ERR(genpd))
470 return -EINVAL;
471
472 /* If power.irq_safe, the PM domain is never powered off. */
473 if (dev->power.irq_safe) {
474 timed = false;
475 goto out;
476 }
477
478 mutex_lock(&genpd->lock);
479 ret = genpd_poweron(genpd, 0);
480 mutex_unlock(&genpd->lock);
481
482 if (ret)
483 return ret;
484
485 out:
486 /* Measure resume latency. */
487 if (timed && runtime_pm)
488 time_start = ktime_get();
489
490 ret = genpd_start_dev(genpd, dev);
491 if (ret)
492 goto err_poweroff;
493
494 ret = genpd_restore_dev(genpd, dev);
495 if (ret)
496 goto err_stop;
497
498 /* Update resume latency value if the measured time exceeds it. */
499 if (timed && runtime_pm) {
500 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
501 if (elapsed_ns > td->resume_latency_ns) {
502 td->resume_latency_ns = elapsed_ns;
503 dev_dbg(dev, "resume latency exceeded, %lld ns\n",
504 elapsed_ns);
505 genpd->max_off_time_changed = true;
506 td->constraint_changed = true;
507 }
508 }
509
510 return 0;
511
512err_stop:
513 genpd_stop_dev(genpd, dev);
514err_poweroff:
515 if (!dev->power.irq_safe) {
516 mutex_lock(&genpd->lock);
517 genpd_poweroff(genpd, 0);
518 mutex_unlock(&genpd->lock);
519 }
520
521 return ret;
522}
523
524static bool pd_ignore_unused;
525static int __init pd_ignore_unused_setup(char *__unused)
526{
527 pd_ignore_unused = true;
528 return 1;
529}
530__setup("pd_ignore_unused", pd_ignore_unused_setup);
531
532/**
533 * genpd_poweroff_unused - Power off all PM domains with no devices in use.
534 */
535static int __init genpd_poweroff_unused(void)
536{
537 struct generic_pm_domain *genpd;
538
539 if (pd_ignore_unused) {
540 pr_warn("genpd: Not disabling unused power domains\n");
541 return 0;
542 }
543
544 mutex_lock(&gpd_list_lock);
545
546 list_for_each_entry(genpd, &gpd_list, gpd_list_node)
547 genpd_queue_power_off_work(genpd);
548
549 mutex_unlock(&gpd_list_lock);
550
551 return 0;
552}
553late_initcall(genpd_poweroff_unused);
554
555#ifdef CONFIG_PM_SLEEP
556
557/**
558 * pm_genpd_present - Check if the given PM domain has been initialized.
559 * @genpd: PM domain to check.
560 */
561static bool pm_genpd_present(const struct generic_pm_domain *genpd)
562{
563 const struct generic_pm_domain *gpd;
564
565 if (IS_ERR_OR_NULL(genpd))
566 return false;
567
568 list_for_each_entry(gpd, &gpd_list, gpd_list_node)
569 if (gpd == genpd)
570 return true;
571
572 return false;
573}
574
575static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
576 struct device *dev)
577{
578 return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
579}
580
581/**
582 * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
583 * @genpd: PM domain to power off, if possible.
584 * @timed: True if latency measurements are allowed.
585 *
586 * Check if the given PM domain can be powered off (during system suspend or
587 * hibernation) and do that if so. Also, in that case propagate to its masters.
588 *
589 * This function is only called in "noirq" and "syscore" stages of system power
590 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
591 * executed sequentially, so it is guaranteed that it will never run twice in
592 * parallel).
593 */
594static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd,
595 bool timed)
596{
597 struct gpd_link *link;
598
599 if (genpd->status == GPD_STATE_POWER_OFF)
600 return;
601
602 if (genpd->suspended_count != genpd->device_count
603 || atomic_read(&genpd->sd_count) > 0)
604 return;
605
606 /* Choose the deepest state when suspending */
607 genpd->state_idx = genpd->state_count - 1;
608 genpd_power_off(genpd, timed);
609
610 genpd->status = GPD_STATE_POWER_OFF;
611
612 list_for_each_entry(link, &genpd->slave_links, slave_node) {
613 genpd_sd_counter_dec(link->master);
614 pm_genpd_sync_poweroff(link->master, timed);
615 }
616}
617
618/**
619 * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
620 * @genpd: PM domain to power on.
621 * @timed: True if latency measurements are allowed.
622 *
623 * This function is only called in "noirq" and "syscore" stages of system power
624 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
625 * executed sequentially, so it is guaranteed that it will never run twice in
626 * parallel).
627 */
628static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd,
629 bool timed)
630{
631 struct gpd_link *link;
632
633 if (genpd->status == GPD_STATE_ACTIVE)
634 return;
635
636 list_for_each_entry(link, &genpd->slave_links, slave_node) {
637 pm_genpd_sync_poweron(link->master, timed);
638 genpd_sd_counter_inc(link->master);
639 }
640
641 genpd_power_on(genpd, timed);
642
643 genpd->status = GPD_STATE_ACTIVE;
644}
645
646/**
647 * resume_needed - Check whether to resume a device before system suspend.
648 * @dev: Device to check.
649 * @genpd: PM domain the device belongs to.
650 *
651 * There are two cases in which a device that can wake up the system from sleep
652 * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
653 * to wake up the system and it has to remain active for this purpose while the
654 * system is in the sleep state and (2) if the device is not enabled to wake up
655 * the system from sleep states and it generally doesn't generate wakeup signals
656 * by itself (those signals are generated on its behalf by other parts of the
657 * system). In the latter case it may be necessary to reconfigure the device's
658 * wakeup settings during system suspend, because it may have been set up to
659 * signal remote wakeup from the system's working state as needed by runtime PM.
660 * Return 'true' in either of the above cases.
661 */
662static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
663{
664 bool active_wakeup;
665
666 if (!device_can_wakeup(dev))
667 return false;
668
669 active_wakeup = genpd_dev_active_wakeup(genpd, dev);
670 return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
671}
672
673/**
674 * pm_genpd_prepare - Start power transition of a device in a PM domain.
675 * @dev: Device to start the transition of.
676 *
677 * Start a power transition of a device (during a system-wide power transition)
678 * under the assumption that its pm_domain field points to the domain member of
679 * an object of type struct generic_pm_domain representing a PM domain
680 * consisting of I/O devices.
681 */
682static int pm_genpd_prepare(struct device *dev)
683{
684 struct generic_pm_domain *genpd;
685 int ret;
686
687 dev_dbg(dev, "%s()\n", __func__);
688
689 genpd = dev_to_genpd(dev);
690 if (IS_ERR(genpd))
691 return -EINVAL;
692
693 /*
694 * If a wakeup request is pending for the device, it should be woken up
695 * at this point and a system wakeup event should be reported if it's
696 * set up to wake up the system from sleep states.
697 */
698 pm_runtime_get_noresume(dev);
699 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
700 pm_wakeup_event(dev, 0);
701
702 if (pm_wakeup_pending()) {
703 pm_runtime_put(dev);
704 return -EBUSY;
705 }
706
707 if (resume_needed(dev, genpd))
708 pm_runtime_resume(dev);
709
710 mutex_lock(&genpd->lock);
711
712 if (genpd->prepared_count++ == 0) {
713 genpd->suspended_count = 0;
714 genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
715 }
716
717 mutex_unlock(&genpd->lock);
718
719 if (genpd->suspend_power_off) {
720 pm_runtime_put_noidle(dev);
721 return 0;
722 }
723
724 /*
725 * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
726 * so genpd_poweron() will return immediately, but if the device
727 * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
728 * to make it operational.
729 */
730 pm_runtime_resume(dev);
731 __pm_runtime_disable(dev, false);
732
733 ret = pm_generic_prepare(dev);
734 if (ret) {
735 mutex_lock(&genpd->lock);
736
737 if (--genpd->prepared_count == 0)
738 genpd->suspend_power_off = false;
739
740 mutex_unlock(&genpd->lock);
741 pm_runtime_enable(dev);
742 }
743
744 pm_runtime_put(dev);
745 return ret;
746}
747
748/**
749 * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
750 * @dev: Device to suspend.
751 *
752 * Suspend a device under the assumption that its pm_domain field points to the
753 * domain member of an object of type struct generic_pm_domain representing
754 * a PM domain consisting of I/O devices.
755 */
756static int pm_genpd_suspend(struct device *dev)
757{
758 struct generic_pm_domain *genpd;
759
760 dev_dbg(dev, "%s()\n", __func__);
761
762 genpd = dev_to_genpd(dev);
763 if (IS_ERR(genpd))
764 return -EINVAL;
765
766 return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev);
767}
768
769/**
770 * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
771 * @dev: Device to suspend.
772 *
773 * Carry out a late suspend of a device under the assumption that its
774 * pm_domain field points to the domain member of an object of type
775 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
776 */
777static int pm_genpd_suspend_late(struct device *dev)
778{
779 struct generic_pm_domain *genpd;
780
781 dev_dbg(dev, "%s()\n", __func__);
782
783 genpd = dev_to_genpd(dev);
784 if (IS_ERR(genpd))
785 return -EINVAL;
786
787 return genpd->suspend_power_off ? 0 : pm_generic_suspend_late(dev);
788}
789
790/**
791 * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
792 * @dev: Device to suspend.
793 *
794 * Stop the device and remove power from the domain if all devices in it have
795 * been stopped.
796 */
797static int pm_genpd_suspend_noirq(struct device *dev)
798{
799 struct generic_pm_domain *genpd;
800
801 dev_dbg(dev, "%s()\n", __func__);
802
803 genpd = dev_to_genpd(dev);
804 if (IS_ERR(genpd))
805 return -EINVAL;
806
807 if (genpd->suspend_power_off
808 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
809 return 0;
810
811 genpd_stop_dev(genpd, dev);
812
813 /*
814 * Since all of the "noirq" callbacks are executed sequentially, it is
815 * guaranteed that this function will never run twice in parallel for
816 * the same PM domain, so it is not necessary to use locking here.
817 */
818 genpd->suspended_count++;
819 pm_genpd_sync_poweroff(genpd, true);
820
821 return 0;
822}
823
824/**
825 * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
826 * @dev: Device to resume.
827 *
828 * Restore power to the device's PM domain, if necessary, and start the device.
829 */
830static int pm_genpd_resume_noirq(struct device *dev)
831{
832 struct generic_pm_domain *genpd;
833
834 dev_dbg(dev, "%s()\n", __func__);
835
836 genpd = dev_to_genpd(dev);
837 if (IS_ERR(genpd))
838 return -EINVAL;
839
840 if (genpd->suspend_power_off
841 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
842 return 0;
843
844 /*
845 * Since all of the "noirq" callbacks are executed sequentially, it is
846 * guaranteed that this function will never run twice in parallel for
847 * the same PM domain, so it is not necessary to use locking here.
848 */
849 pm_genpd_sync_poweron(genpd, true);
850 genpd->suspended_count--;
851
852 return genpd_start_dev(genpd, dev);
853}
854
855/**
856 * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
857 * @dev: Device to resume.
858 *
859 * Carry out an early resume of a device under the assumption that its
860 * pm_domain field points to the domain member of an object of type
861 * struct generic_pm_domain representing a power domain consisting of I/O
862 * devices.
863 */
864static int pm_genpd_resume_early(struct device *dev)
865{
866 struct generic_pm_domain *genpd;
867
868 dev_dbg(dev, "%s()\n", __func__);
869
870 genpd = dev_to_genpd(dev);
871 if (IS_ERR(genpd))
872 return -EINVAL;
873
874 return genpd->suspend_power_off ? 0 : pm_generic_resume_early(dev);
875}
876
877/**
878 * pm_genpd_resume - Resume of device in an I/O PM domain.
879 * @dev: Device to resume.
880 *
881 * Resume a device under the assumption that its pm_domain field points to the
882 * domain member of an object of type struct generic_pm_domain representing
883 * a power domain consisting of I/O devices.
884 */
885static int pm_genpd_resume(struct device *dev)
886{
887 struct generic_pm_domain *genpd;
888
889 dev_dbg(dev, "%s()\n", __func__);
890
891 genpd = dev_to_genpd(dev);
892 if (IS_ERR(genpd))
893 return -EINVAL;
894
895 return genpd->suspend_power_off ? 0 : pm_generic_resume(dev);
896}
897
898/**
899 * pm_genpd_freeze - Freezing a device in an I/O PM domain.
900 * @dev: Device to freeze.
901 *
902 * Freeze a device under the assumption that its pm_domain field points to the
903 * domain member of an object of type struct generic_pm_domain representing
904 * a power domain consisting of I/O devices.
905 */
906static int pm_genpd_freeze(struct device *dev)
907{
908 struct generic_pm_domain *genpd;
909
910 dev_dbg(dev, "%s()\n", __func__);
911
912 genpd = dev_to_genpd(dev);
913 if (IS_ERR(genpd))
914 return -EINVAL;
915
916 return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev);
917}
918
919/**
920 * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
921 * @dev: Device to freeze.
922 *
923 * Carry out a late freeze of a device under the assumption that its
924 * pm_domain field points to the domain member of an object of type
925 * struct generic_pm_domain representing a power domain consisting of I/O
926 * devices.
927 */
928static int pm_genpd_freeze_late(struct device *dev)
929{
930 struct generic_pm_domain *genpd;
931
932 dev_dbg(dev, "%s()\n", __func__);
933
934 genpd = dev_to_genpd(dev);
935 if (IS_ERR(genpd))
936 return -EINVAL;
937
938 return genpd->suspend_power_off ? 0 : pm_generic_freeze_late(dev);
939}
940
941/**
942 * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
943 * @dev: Device to freeze.
944 *
945 * Carry out a late freeze of a device under the assumption that its
946 * pm_domain field points to the domain member of an object of type
947 * struct generic_pm_domain representing a power domain consisting of I/O
948 * devices.
949 */
950static int pm_genpd_freeze_noirq(struct device *dev)
951{
952 struct generic_pm_domain *genpd;
953
954 dev_dbg(dev, "%s()\n", __func__);
955
956 genpd = dev_to_genpd(dev);
957 if (IS_ERR(genpd))
958 return -EINVAL;
959
960 return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
961}
962
963/**
964 * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
965 * @dev: Device to thaw.
966 *
967 * Start the device, unless power has been removed from the domain already
968 * before the system transition.
969 */
970static int pm_genpd_thaw_noirq(struct device *dev)
971{
972 struct generic_pm_domain *genpd;
973
974 dev_dbg(dev, "%s()\n", __func__);
975
976 genpd = dev_to_genpd(dev);
977 if (IS_ERR(genpd))
978 return -EINVAL;
979
980 return genpd->suspend_power_off ?
981 0 : genpd_start_dev(genpd, dev);
982}
983
984/**
985 * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
986 * @dev: Device to thaw.
987 *
988 * Carry out an early thaw of a device under the assumption that its
989 * pm_domain field points to the domain member of an object of type
990 * struct generic_pm_domain representing a power domain consisting of I/O
991 * devices.
992 */
993static int pm_genpd_thaw_early(struct device *dev)
994{
995 struct generic_pm_domain *genpd;
996
997 dev_dbg(dev, "%s()\n", __func__);
998
999 genpd = dev_to_genpd(dev);
1000 if (IS_ERR(genpd))
1001 return -EINVAL;
1002
1003 return genpd->suspend_power_off ? 0 : pm_generic_thaw_early(dev);
1004}
1005
1006/**
1007 * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
1008 * @dev: Device to thaw.
1009 *
1010 * Thaw a device under the assumption that its pm_domain field points to the
1011 * domain member of an object of type struct generic_pm_domain representing
1012 * a power domain consisting of I/O devices.
1013 */
1014static int pm_genpd_thaw(struct device *dev)
1015{
1016 struct generic_pm_domain *genpd;
1017
1018 dev_dbg(dev, "%s()\n", __func__);
1019
1020 genpd = dev_to_genpd(dev);
1021 if (IS_ERR(genpd))
1022 return -EINVAL;
1023
1024 return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev);
1025}
1026
1027/**
1028 * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1029 * @dev: Device to resume.
1030 *
1031 * Make sure the domain will be in the same power state as before the
1032 * hibernation the system is resuming from and start the device if necessary.
1033 */
1034static int pm_genpd_restore_noirq(struct device *dev)
1035{
1036 struct generic_pm_domain *genpd;
1037
1038 dev_dbg(dev, "%s()\n", __func__);
1039
1040 genpd = dev_to_genpd(dev);
1041 if (IS_ERR(genpd))
1042 return -EINVAL;
1043
1044 /*
1045 * Since all of the "noirq" callbacks are executed sequentially, it is
1046 * guaranteed that this function will never run twice in parallel for
1047 * the same PM domain, so it is not necessary to use locking here.
1048 *
1049 * At this point suspended_count == 0 means we are being run for the
1050 * first time for the given domain in the present cycle.
1051 */
1052 if (genpd->suspended_count++ == 0) {
1053 /*
1054 * The boot kernel might put the domain into arbitrary state,
1055 * so make it appear as powered off to pm_genpd_sync_poweron(),
1056 * so that it tries to power it on in case it was really off.
1057 */
1058 genpd->status = GPD_STATE_POWER_OFF;
1059 if (genpd->suspend_power_off) {
1060 /*
1061 * If the domain was off before the hibernation, make
1062 * sure it will be off going forward.
1063 */
1064 genpd_power_off(genpd, true);
1065
1066 return 0;
1067 }
1068 }
1069
1070 if (genpd->suspend_power_off)
1071 return 0;
1072
1073 pm_genpd_sync_poweron(genpd, true);
1074
1075 return genpd_start_dev(genpd, dev);
1076}
1077
1078/**
1079 * pm_genpd_complete - Complete power transition of a device in a power domain.
1080 * @dev: Device to complete the transition of.
1081 *
1082 * Complete a power transition of a device (during a system-wide power
1083 * transition) under the assumption that its pm_domain field points to the
1084 * domain member of an object of type struct generic_pm_domain representing
1085 * a power domain consisting of I/O devices.
1086 */
1087static void pm_genpd_complete(struct device *dev)
1088{
1089 struct generic_pm_domain *genpd;
1090 bool run_complete;
1091
1092 dev_dbg(dev, "%s()\n", __func__);
1093
1094 genpd = dev_to_genpd(dev);
1095 if (IS_ERR(genpd))
1096 return;
1097
1098 mutex_lock(&genpd->lock);
1099
1100 run_complete = !genpd->suspend_power_off;
1101 if (--genpd->prepared_count == 0)
1102 genpd->suspend_power_off = false;
1103
1104 mutex_unlock(&genpd->lock);
1105
1106 if (run_complete) {
1107 pm_generic_complete(dev);
1108 pm_runtime_set_active(dev);
1109 pm_runtime_enable(dev);
1110 pm_request_idle(dev);
1111 }
1112}
1113
1114/**
1115 * genpd_syscore_switch - Switch power during system core suspend or resume.
1116 * @dev: Device that normally is marked as "always on" to switch power for.
1117 *
1118 * This routine may only be called during the system core (syscore) suspend or
1119 * resume phase for devices whose "always on" flags are set.
1120 */
1121static void genpd_syscore_switch(struct device *dev, bool suspend)
1122{
1123 struct generic_pm_domain *genpd;
1124
1125 genpd = dev_to_genpd(dev);
1126 if (!pm_genpd_present(genpd))
1127 return;
1128
1129 if (suspend) {
1130 genpd->suspended_count++;
1131 pm_genpd_sync_poweroff(genpd, false);
1132 } else {
1133 pm_genpd_sync_poweron(genpd, false);
1134 genpd->suspended_count--;
1135 }
1136}
1137
1138void pm_genpd_syscore_poweroff(struct device *dev)
1139{
1140 genpd_syscore_switch(dev, true);
1141}
1142EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweroff);
1143
1144void pm_genpd_syscore_poweron(struct device *dev)
1145{
1146 genpd_syscore_switch(dev, false);
1147}
1148EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
1149
1150#else /* !CONFIG_PM_SLEEP */
1151
1152#define pm_genpd_prepare NULL
1153#define pm_genpd_suspend NULL
1154#define pm_genpd_suspend_late NULL
1155#define pm_genpd_suspend_noirq NULL
1156#define pm_genpd_resume_early NULL
1157#define pm_genpd_resume_noirq NULL
1158#define pm_genpd_resume NULL
1159#define pm_genpd_freeze NULL
1160#define pm_genpd_freeze_late NULL
1161#define pm_genpd_freeze_noirq NULL
1162#define pm_genpd_thaw_early NULL
1163#define pm_genpd_thaw_noirq NULL
1164#define pm_genpd_thaw NULL
1165#define pm_genpd_restore_noirq NULL
1166#define pm_genpd_complete NULL
1167
1168#endif /* CONFIG_PM_SLEEP */
1169
1170static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
1171 struct generic_pm_domain *genpd,
1172 struct gpd_timing_data *td)
1173{
1174 struct generic_pm_domain_data *gpd_data;
1175 int ret;
1176
1177 ret = dev_pm_get_subsys_data(dev);
1178 if (ret)
1179 return ERR_PTR(ret);
1180
1181 gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1182 if (!gpd_data) {
1183 ret = -ENOMEM;
1184 goto err_put;
1185 }
1186
1187 if (td)
1188 gpd_data->td = *td;
1189
1190 gpd_data->base.dev = dev;
1191 gpd_data->td.constraint_changed = true;
1192 gpd_data->td.effective_constraint_ns = -1;
1193 gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1194
1195 spin_lock_irq(&dev->power.lock);
1196
1197 if (dev->power.subsys_data->domain_data) {
1198 ret = -EINVAL;
1199 goto err_free;
1200 }
1201
1202 dev->power.subsys_data->domain_data = &gpd_data->base;
1203
1204 spin_unlock_irq(&dev->power.lock);
1205
1206 dev_pm_domain_set(dev, &genpd->domain);
1207
1208 return gpd_data;
1209
1210 err_free:
1211 spin_unlock_irq(&dev->power.lock);
1212 kfree(gpd_data);
1213 err_put:
1214 dev_pm_put_subsys_data(dev);
1215 return ERR_PTR(ret);
1216}
1217
1218static void genpd_free_dev_data(struct device *dev,
1219 struct generic_pm_domain_data *gpd_data)
1220{
1221 dev_pm_domain_set(dev, NULL);
1222
1223 spin_lock_irq(&dev->power.lock);
1224
1225 dev->power.subsys_data->domain_data = NULL;
1226
1227 spin_unlock_irq(&dev->power.lock);
1228
1229 kfree(gpd_data);
1230 dev_pm_put_subsys_data(dev);
1231}
1232
1233/**
1234 * __pm_genpd_add_device - Add a device to an I/O PM domain.
1235 * @genpd: PM domain to add the device to.
1236 * @dev: Device to be added.
1237 * @td: Set of PM QoS timing parameters to attach to the device.
1238 */
1239int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1240 struct gpd_timing_data *td)
1241{
1242 struct generic_pm_domain_data *gpd_data;
1243 int ret = 0;
1244
1245 dev_dbg(dev, "%s()\n", __func__);
1246
1247 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1248 return -EINVAL;
1249
1250 gpd_data = genpd_alloc_dev_data(dev, genpd, td);
1251 if (IS_ERR(gpd_data))
1252 return PTR_ERR(gpd_data);
1253
1254 mutex_lock(&genpd->lock);
1255
1256 if (genpd->prepared_count > 0) {
1257 ret = -EAGAIN;
1258 goto out;
1259 }
1260
1261 ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1262 if (ret)
1263 goto out;
1264
1265 genpd->device_count++;
1266 genpd->max_off_time_changed = true;
1267
1268 list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1269
1270 out:
1271 mutex_unlock(&genpd->lock);
1272
1273 if (ret)
1274 genpd_free_dev_data(dev, gpd_data);
1275 else
1276 dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1277
1278 return ret;
1279}
1280EXPORT_SYMBOL_GPL(__pm_genpd_add_device);
1281
1282/**
1283 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1284 * @genpd: PM domain to remove the device from.
1285 * @dev: Device to be removed.
1286 */
1287int pm_genpd_remove_device(struct generic_pm_domain *genpd,
1288 struct device *dev)
1289{
1290 struct generic_pm_domain_data *gpd_data;
1291 struct pm_domain_data *pdd;
1292 int ret = 0;
1293
1294 dev_dbg(dev, "%s()\n", __func__);
1295
1296 if (!genpd || genpd != pm_genpd_lookup_dev(dev))
1297 return -EINVAL;
1298
1299 /* The above validation also means we have existing domain_data. */
1300 pdd = dev->power.subsys_data->domain_data;
1301 gpd_data = to_gpd_data(pdd);
1302 dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
1303
1304 mutex_lock(&genpd->lock);
1305
1306 if (genpd->prepared_count > 0) {
1307 ret = -EAGAIN;
1308 goto out;
1309 }
1310
1311 genpd->device_count--;
1312 genpd->max_off_time_changed = true;
1313
1314 if (genpd->detach_dev)
1315 genpd->detach_dev(genpd, dev);
1316
1317 list_del_init(&pdd->list_node);
1318
1319 mutex_unlock(&genpd->lock);
1320
1321 genpd_free_dev_data(dev, gpd_data);
1322
1323 return 0;
1324
1325 out:
1326 mutex_unlock(&genpd->lock);
1327 dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1328
1329 return ret;
1330}
1331EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
1332
1333/**
1334 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1335 * @genpd: Master PM domain to add the subdomain to.
1336 * @subdomain: Subdomain to be added.
1337 */
1338int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1339 struct generic_pm_domain *subdomain)
1340{
1341 struct gpd_link *link, *itr;
1342 int ret = 0;
1343
1344 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1345 || genpd == subdomain)
1346 return -EINVAL;
1347
1348 link = kzalloc(sizeof(*link), GFP_KERNEL);
1349 if (!link)
1350 return -ENOMEM;
1351
1352 mutex_lock(&subdomain->lock);
1353 mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
1354
1355 if (genpd->status == GPD_STATE_POWER_OFF
1356 && subdomain->status != GPD_STATE_POWER_OFF) {
1357 ret = -EINVAL;
1358 goto out;
1359 }
1360
1361 list_for_each_entry(itr, &genpd->master_links, master_node) {
1362 if (itr->slave == subdomain && itr->master == genpd) {
1363 ret = -EINVAL;
1364 goto out;
1365 }
1366 }
1367
1368 link->master = genpd;
1369 list_add_tail(&link->master_node, &genpd->master_links);
1370 link->slave = subdomain;
1371 list_add_tail(&link->slave_node, &subdomain->slave_links);
1372 if (subdomain->status != GPD_STATE_POWER_OFF)
1373 genpd_sd_counter_inc(genpd);
1374
1375 out:
1376 mutex_unlock(&genpd->lock);
1377 mutex_unlock(&subdomain->lock);
1378 if (ret)
1379 kfree(link);
1380 return ret;
1381}
1382EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
1383
1384/**
1385 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1386 * @genpd: Master PM domain to remove the subdomain from.
1387 * @subdomain: Subdomain to be removed.
1388 */
1389int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1390 struct generic_pm_domain *subdomain)
1391{
1392 struct gpd_link *link;
1393 int ret = -EINVAL;
1394
1395 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1396 return -EINVAL;
1397
1398 mutex_lock(&subdomain->lock);
1399 mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
1400
1401 if (!list_empty(&subdomain->master_links) || subdomain->device_count) {
1402 pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
1403 subdomain->name);
1404 ret = -EBUSY;
1405 goto out;
1406 }
1407
1408 list_for_each_entry(link, &genpd->master_links, master_node) {
1409 if (link->slave != subdomain)
1410 continue;
1411
1412 list_del(&link->master_node);
1413 list_del(&link->slave_node);
1414 kfree(link);
1415 if (subdomain->status != GPD_STATE_POWER_OFF)
1416 genpd_sd_counter_dec(genpd);
1417
1418 ret = 0;
1419 break;
1420 }
1421
1422out:
1423 mutex_unlock(&genpd->lock);
1424 mutex_unlock(&subdomain->lock);
1425
1426 return ret;
1427}
1428EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
1429
1430/* Default device callbacks for generic PM domains. */
1431
1432/**
1433 * pm_genpd_default_save_state - Default "save device state" for PM domains.
1434 * @dev: Device to handle.
1435 */
1436static int pm_genpd_default_save_state(struct device *dev)
1437{
1438 int (*cb)(struct device *__dev);
1439
1440 if (dev->type && dev->type->pm)
1441 cb = dev->type->pm->runtime_suspend;
1442 else if (dev->class && dev->class->pm)
1443 cb = dev->class->pm->runtime_suspend;
1444 else if (dev->bus && dev->bus->pm)
1445 cb = dev->bus->pm->runtime_suspend;
1446 else
1447 cb = NULL;
1448
1449 if (!cb && dev->driver && dev->driver->pm)
1450 cb = dev->driver->pm->runtime_suspend;
1451
1452 return cb ? cb(dev) : 0;
1453}
1454
1455/**
1456 * pm_genpd_default_restore_state - Default PM domains "restore device state".
1457 * @dev: Device to handle.
1458 */
1459static int pm_genpd_default_restore_state(struct device *dev)
1460{
1461 int (*cb)(struct device *__dev);
1462
1463 if (dev->type && dev->type->pm)
1464 cb = dev->type->pm->runtime_resume;
1465 else if (dev->class && dev->class->pm)
1466 cb = dev->class->pm->runtime_resume;
1467 else if (dev->bus && dev->bus->pm)
1468 cb = dev->bus->pm->runtime_resume;
1469 else
1470 cb = NULL;
1471
1472 if (!cb && dev->driver && dev->driver->pm)
1473 cb = dev->driver->pm->runtime_resume;
1474
1475 return cb ? cb(dev) : 0;
1476}
1477
1478/**
1479 * pm_genpd_init - Initialize a generic I/O PM domain object.
1480 * @genpd: PM domain object to initialize.
1481 * @gov: PM domain governor to associate with the domain (may be NULL).
1482 * @is_off: Initial value of the domain's power_is_off field.
1483 */
1484void pm_genpd_init(struct generic_pm_domain *genpd,
1485 struct dev_power_governor *gov, bool is_off)
1486{
1487 if (IS_ERR_OR_NULL(genpd))
1488 return;
1489
1490 INIT_LIST_HEAD(&genpd->master_links);
1491 INIT_LIST_HEAD(&genpd->slave_links);
1492 INIT_LIST_HEAD(&genpd->dev_list);
1493 mutex_init(&genpd->lock);
1494 genpd->gov = gov;
1495 INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
1496 atomic_set(&genpd->sd_count, 0);
1497 genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
1498 genpd->device_count = 0;
1499 genpd->max_off_time_ns = -1;
1500 genpd->max_off_time_changed = true;
1501 genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
1502 genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
1503 genpd->domain.ops.prepare = pm_genpd_prepare;
1504 genpd->domain.ops.suspend = pm_genpd_suspend;
1505 genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
1506 genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
1507 genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
1508 genpd->domain.ops.resume_early = pm_genpd_resume_early;
1509 genpd->domain.ops.resume = pm_genpd_resume;
1510 genpd->domain.ops.freeze = pm_genpd_freeze;
1511 genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
1512 genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
1513 genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
1514 genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
1515 genpd->domain.ops.thaw = pm_genpd_thaw;
1516 genpd->domain.ops.poweroff = pm_genpd_suspend;
1517 genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
1518 genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
1519 genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
1520 genpd->domain.ops.restore_early = pm_genpd_resume_early;
1521 genpd->domain.ops.restore = pm_genpd_resume;
1522 genpd->domain.ops.complete = pm_genpd_complete;
1523 genpd->dev_ops.save_state = pm_genpd_default_save_state;
1524 genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
1525
1526 if (genpd->flags & GENPD_FLAG_PM_CLK) {
1527 genpd->dev_ops.stop = pm_clk_suspend;
1528 genpd->dev_ops.start = pm_clk_resume;
1529 }
1530
1531 if (genpd->state_idx >= GENPD_MAX_NUM_STATES) {
1532 pr_warn("Initial state index out of bounds.\n");
1533 genpd->state_idx = GENPD_MAX_NUM_STATES - 1;
1534 }
1535
1536 if (genpd->state_count > GENPD_MAX_NUM_STATES) {
1537 pr_warn("Limiting states to %d\n", GENPD_MAX_NUM_STATES);
1538 genpd->state_count = GENPD_MAX_NUM_STATES;
1539 }
1540
1541 /* Use only one "off" state if there were no states declared */
1542 if (genpd->state_count == 0)
1543 genpd->state_count = 1;
1544
1545 mutex_lock(&gpd_list_lock);
1546 list_add(&genpd->gpd_list_node, &gpd_list);
1547 mutex_unlock(&gpd_list_lock);
1548}
1549EXPORT_SYMBOL_GPL(pm_genpd_init);
1550
1551#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
1552/*
1553 * Device Tree based PM domain providers.
1554 *
1555 * The code below implements generic device tree based PM domain providers that
1556 * bind device tree nodes with generic PM domains registered in the system.
1557 *
1558 * Any driver that registers generic PM domains and needs to support binding of
1559 * devices to these domains is supposed to register a PM domain provider, which
1560 * maps a PM domain specifier retrieved from the device tree to a PM domain.
1561 *
1562 * Two simple mapping functions have been provided for convenience:
1563 * - __of_genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
1564 * - __of_genpd_xlate_onecell() for mapping of multiple PM domains per node by
1565 * index.
1566 */
1567
1568/**
1569 * struct of_genpd_provider - PM domain provider registration structure
1570 * @link: Entry in global list of PM domain providers
1571 * @node: Pointer to device tree node of PM domain provider
1572 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
1573 * into a PM domain.
1574 * @data: context pointer to be passed into @xlate callback
1575 */
1576struct of_genpd_provider {
1577 struct list_head link;
1578 struct device_node *node;
1579 genpd_xlate_t xlate;
1580 void *data;
1581};
1582
1583/* List of registered PM domain providers. */
1584static LIST_HEAD(of_genpd_providers);
1585/* Mutex to protect the list above. */
1586static DEFINE_MUTEX(of_genpd_mutex);
1587
1588/**
1589 * __of_genpd_xlate_simple() - Xlate function for direct node-domain mapping
1590 * @genpdspec: OF phandle args to map into a PM domain
1591 * @data: xlate function private data - pointer to struct generic_pm_domain
1592 *
1593 * This is a generic xlate function that can be used to model PM domains that
1594 * have their own device tree nodes. The private data of xlate function needs
1595 * to be a valid pointer to struct generic_pm_domain.
1596 */
1597struct generic_pm_domain *__of_genpd_xlate_simple(
1598 struct of_phandle_args *genpdspec,
1599 void *data)
1600{
1601 if (genpdspec->args_count != 0)
1602 return ERR_PTR(-EINVAL);
1603 return data;
1604}
1605EXPORT_SYMBOL_GPL(__of_genpd_xlate_simple);
1606
1607/**
1608 * __of_genpd_xlate_onecell() - Xlate function using a single index.
1609 * @genpdspec: OF phandle args to map into a PM domain
1610 * @data: xlate function private data - pointer to struct genpd_onecell_data
1611 *
1612 * This is a generic xlate function that can be used to model simple PM domain
1613 * controllers that have one device tree node and provide multiple PM domains.
1614 * A single cell is used as an index into an array of PM domains specified in
1615 * the genpd_onecell_data struct when registering the provider.
1616 */
1617struct generic_pm_domain *__of_genpd_xlate_onecell(
1618 struct of_phandle_args *genpdspec,
1619 void *data)
1620{
1621 struct genpd_onecell_data *genpd_data = data;
1622 unsigned int idx = genpdspec->args[0];
1623
1624 if (genpdspec->args_count != 1)
1625 return ERR_PTR(-EINVAL);
1626
1627 if (idx >= genpd_data->num_domains) {
1628 pr_err("%s: invalid domain index %u\n", __func__, idx);
1629 return ERR_PTR(-EINVAL);
1630 }
1631
1632 if (!genpd_data->domains[idx])
1633 return ERR_PTR(-ENOENT);
1634
1635 return genpd_data->domains[idx];
1636}
1637EXPORT_SYMBOL_GPL(__of_genpd_xlate_onecell);
1638
1639/**
1640 * __of_genpd_add_provider() - Register a PM domain provider for a node
1641 * @np: Device node pointer associated with the PM domain provider.
1642 * @xlate: Callback for decoding PM domain from phandle arguments.
1643 * @data: Context pointer for @xlate callback.
1644 */
1645int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
1646 void *data)
1647{
1648 struct of_genpd_provider *cp;
1649
1650 cp = kzalloc(sizeof(*cp), GFP_KERNEL);
1651 if (!cp)
1652 return -ENOMEM;
1653
1654 cp->node = of_node_get(np);
1655 cp->data = data;
1656 cp->xlate = xlate;
1657
1658 mutex_lock(&of_genpd_mutex);
1659 list_add(&cp->link, &of_genpd_providers);
1660 mutex_unlock(&of_genpd_mutex);
1661 pr_debug("Added domain provider from %s\n", np->full_name);
1662
1663 return 0;
1664}
1665EXPORT_SYMBOL_GPL(__of_genpd_add_provider);
1666
1667/**
1668 * of_genpd_del_provider() - Remove a previously registered PM domain provider
1669 * @np: Device node pointer associated with the PM domain provider
1670 */
1671void of_genpd_del_provider(struct device_node *np)
1672{
1673 struct of_genpd_provider *cp;
1674
1675 mutex_lock(&of_genpd_mutex);
1676 list_for_each_entry(cp, &of_genpd_providers, link) {
1677 if (cp->node == np) {
1678 list_del(&cp->link);
1679 of_node_put(cp->node);
1680 kfree(cp);
1681 break;
1682 }
1683 }
1684 mutex_unlock(&of_genpd_mutex);
1685}
1686EXPORT_SYMBOL_GPL(of_genpd_del_provider);
1687
1688/**
1689 * of_genpd_get_from_provider() - Look-up PM domain
1690 * @genpdspec: OF phandle args to use for look-up
1691 *
1692 * Looks for a PM domain provider under the node specified by @genpdspec and if
1693 * found, uses xlate function of the provider to map phandle args to a PM
1694 * domain.
1695 *
1696 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
1697 * on failure.
1698 */
1699struct generic_pm_domain *of_genpd_get_from_provider(
1700 struct of_phandle_args *genpdspec)
1701{
1702 struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
1703 struct of_genpd_provider *provider;
1704
1705 if (!genpdspec)
1706 return ERR_PTR(-EINVAL);
1707
1708 mutex_lock(&of_genpd_mutex);
1709
1710 /* Check if we have such a provider in our array */
1711 list_for_each_entry(provider, &of_genpd_providers, link) {
1712 if (provider->node == genpdspec->np)
1713 genpd = provider->xlate(genpdspec, provider->data);
1714 if (!IS_ERR(genpd))
1715 break;
1716 }
1717
1718 mutex_unlock(&of_genpd_mutex);
1719
1720 return genpd;
1721}
1722EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
1723
1724/**
1725 * genpd_dev_pm_detach - Detach a device from its PM domain.
1726 * @dev: Device to detach.
1727 * @power_off: Currently not used
1728 *
1729 * Try to locate a corresponding generic PM domain, which the device was
1730 * attached to previously. If such is found, the device is detached from it.
1731 */
1732static void genpd_dev_pm_detach(struct device *dev, bool power_off)
1733{
1734 struct generic_pm_domain *pd;
1735 unsigned int i;
1736 int ret = 0;
1737
1738 pd = pm_genpd_lookup_dev(dev);
1739 if (!pd)
1740 return;
1741
1742 dev_dbg(dev, "removing from PM domain %s\n", pd->name);
1743
1744 for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1745 ret = pm_genpd_remove_device(pd, dev);
1746 if (ret != -EAGAIN)
1747 break;
1748
1749 mdelay(i);
1750 cond_resched();
1751 }
1752
1753 if (ret < 0) {
1754 dev_err(dev, "failed to remove from PM domain %s: %d",
1755 pd->name, ret);
1756 return;
1757 }
1758
1759 /* Check if PM domain can be powered off after removing this device. */
1760 genpd_queue_power_off_work(pd);
1761}
1762
1763static void genpd_dev_pm_sync(struct device *dev)
1764{
1765 struct generic_pm_domain *pd;
1766
1767 pd = dev_to_genpd(dev);
1768 if (IS_ERR(pd))
1769 return;
1770
1771 genpd_queue_power_off_work(pd);
1772}
1773
1774/**
1775 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
1776 * @dev: Device to attach.
1777 *
1778 * Parse device's OF node to find a PM domain specifier. If such is found,
1779 * attaches the device to retrieved pm_domain ops.
1780 *
1781 * Both generic and legacy Samsung-specific DT bindings are supported to keep
1782 * backwards compatibility with existing DTBs.
1783 *
1784 * Returns 0 on successfully attached PM domain or negative error code. Note
1785 * that if a power-domain exists for the device, but it cannot be found or
1786 * turned on, then return -EPROBE_DEFER to ensure that the device is not
1787 * probed and to re-try again later.
1788 */
1789int genpd_dev_pm_attach(struct device *dev)
1790{
1791 struct of_phandle_args pd_args;
1792 struct generic_pm_domain *pd;
1793 unsigned int i;
1794 int ret;
1795
1796 if (!dev->of_node)
1797 return -ENODEV;
1798
1799 if (dev->pm_domain)
1800 return -EEXIST;
1801
1802 ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
1803 "#power-domain-cells", 0, &pd_args);
1804 if (ret < 0) {
1805 if (ret != -ENOENT)
1806 return ret;
1807
1808 /*
1809 * Try legacy Samsung-specific bindings
1810 * (for backwards compatibility of DT ABI)
1811 */
1812 pd_args.args_count = 0;
1813 pd_args.np = of_parse_phandle(dev->of_node,
1814 "samsung,power-domain", 0);
1815 if (!pd_args.np)
1816 return -ENOENT;
1817 }
1818
1819 pd = of_genpd_get_from_provider(&pd_args);
1820 of_node_put(pd_args.np);
1821 if (IS_ERR(pd)) {
1822 dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
1823 __func__, PTR_ERR(pd));
1824 return -EPROBE_DEFER;
1825 }
1826
1827 dev_dbg(dev, "adding to PM domain %s\n", pd->name);
1828
1829 for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1830 ret = pm_genpd_add_device(pd, dev);
1831 if (ret != -EAGAIN)
1832 break;
1833
1834 mdelay(i);
1835 cond_resched();
1836 }
1837
1838 if (ret < 0) {
1839 dev_err(dev, "failed to add to PM domain %s: %d",
1840 pd->name, ret);
1841 goto out;
1842 }
1843
1844 dev->pm_domain->detach = genpd_dev_pm_detach;
1845 dev->pm_domain->sync = genpd_dev_pm_sync;
1846
1847 mutex_lock(&pd->lock);
1848 ret = genpd_poweron(pd, 0);
1849 mutex_unlock(&pd->lock);
1850out:
1851 return ret ? -EPROBE_DEFER : 0;
1852}
1853EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
1854#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
1855
1856
1857/*** debugfs support ***/
1858
1859#ifdef CONFIG_PM_ADVANCED_DEBUG
1860#include <linux/pm.h>
1861#include <linux/device.h>
1862#include <linux/debugfs.h>
1863#include <linux/seq_file.h>
1864#include <linux/init.h>
1865#include <linux/kobject.h>
1866static struct dentry *pm_genpd_debugfs_dir;
1867
1868/*
1869 * TODO: This function is a slightly modified version of rtpm_status_show
1870 * from sysfs.c, so generalize it.
1871 */
1872static void rtpm_status_str(struct seq_file *s, struct device *dev)
1873{
1874 static const char * const status_lookup[] = {
1875 [RPM_ACTIVE] = "active",
1876 [RPM_RESUMING] = "resuming",
1877 [RPM_SUSPENDED] = "suspended",
1878 [RPM_SUSPENDING] = "suspending"
1879 };
1880 const char *p = "";
1881
1882 if (dev->power.runtime_error)
1883 p = "error";
1884 else if (dev->power.disable_depth)
1885 p = "unsupported";
1886 else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
1887 p = status_lookup[dev->power.runtime_status];
1888 else
1889 WARN_ON(1);
1890
1891 seq_puts(s, p);
1892}
1893
1894static int pm_genpd_summary_one(struct seq_file *s,
1895 struct generic_pm_domain *genpd)
1896{
1897 static const char * const status_lookup[] = {
1898 [GPD_STATE_ACTIVE] = "on",
1899 [GPD_STATE_POWER_OFF] = "off"
1900 };
1901 struct pm_domain_data *pm_data;
1902 const char *kobj_path;
1903 struct gpd_link *link;
1904 char state[16];
1905 int ret;
1906
1907 ret = mutex_lock_interruptible(&genpd->lock);
1908 if (ret)
1909 return -ERESTARTSYS;
1910
1911 if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
1912 goto exit;
1913 if (genpd->status == GPD_STATE_POWER_OFF)
1914 snprintf(state, sizeof(state), "%s-%u",
1915 status_lookup[genpd->status], genpd->state_idx);
1916 else
1917 snprintf(state, sizeof(state), "%s",
1918 status_lookup[genpd->status]);
1919 seq_printf(s, "%-30s %-15s ", genpd->name, state);
1920
1921 /*
1922 * Modifications on the list require holding locks on both
1923 * master and slave, so we are safe.
1924 * Also genpd->name is immutable.
1925 */
1926 list_for_each_entry(link, &genpd->master_links, master_node) {
1927 seq_printf(s, "%s", link->slave->name);
1928 if (!list_is_last(&link->master_node, &genpd->master_links))
1929 seq_puts(s, ", ");
1930 }
1931
1932 list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
1933 kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL);
1934 if (kobj_path == NULL)
1935 continue;
1936
1937 seq_printf(s, "\n %-50s ", kobj_path);
1938 rtpm_status_str(s, pm_data->dev);
1939 kfree(kobj_path);
1940 }
1941
1942 seq_puts(s, "\n");
1943exit:
1944 mutex_unlock(&genpd->lock);
1945
1946 return 0;
1947}
1948
1949static int pm_genpd_summary_show(struct seq_file *s, void *data)
1950{
1951 struct generic_pm_domain *genpd;
1952 int ret = 0;
1953
1954 seq_puts(s, "domain status slaves\n");
1955 seq_puts(s, " /device runtime status\n");
1956 seq_puts(s, "----------------------------------------------------------------------\n");
1957
1958 ret = mutex_lock_interruptible(&gpd_list_lock);
1959 if (ret)
1960 return -ERESTARTSYS;
1961
1962 list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
1963 ret = pm_genpd_summary_one(s, genpd);
1964 if (ret)
1965 break;
1966 }
1967 mutex_unlock(&gpd_list_lock);
1968
1969 return ret;
1970}
1971
1972static int pm_genpd_summary_open(struct inode *inode, struct file *file)
1973{
1974 return single_open(file, pm_genpd_summary_show, NULL);
1975}
1976
1977static const struct file_operations pm_genpd_summary_fops = {
1978 .open = pm_genpd_summary_open,
1979 .read = seq_read,
1980 .llseek = seq_lseek,
1981 .release = single_release,
1982};
1983
1984static int __init pm_genpd_debug_init(void)
1985{
1986 struct dentry *d;
1987
1988 pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
1989
1990 if (!pm_genpd_debugfs_dir)
1991 return -ENOMEM;
1992
1993 d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
1994 pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops);
1995 if (!d)
1996 return -ENOMEM;
1997
1998 return 0;
1999}
2000late_initcall(pm_genpd_debug_init);
2001
2002static void __exit pm_genpd_debug_exit(void)
2003{
2004 debugfs_remove_recursive(pm_genpd_debugfs_dir);
2005}
2006__exitcall(pm_genpd_debug_exit);
2007#endif /* CONFIG_PM_ADVANCED_DEBUG */