aboutsummaryrefslogtreecommitdiffstats
path: root/patches.runtime_pm/0007-PM-Domains-System-wide-transitions-support-for-gener.patch
blob: 9487f1dfa507d06391f21af4effa74c26e60f1a7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
From e09ec39629e6f819c4828081038af88e531664cd Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rjw@sisk.pl>
Date: Fri, 1 Jul 2011 22:13:19 +0200
Subject: PM / Domains: System-wide transitions support for generic domains
 (v5)

Make generic PM domains support system-wide power transitions
(system suspend and hibernation).  Add suspend, resume, freeze, thaw,
poweroff and restore callbacks to be associated with struct
generic_pm_domain objects and make pm_genpd_init() use them as
appropriate.

The new callbacks do nothing for devices belonging to power domains
that were powered down at run time (before the transition).  For the
other devices the action carried out depends on the type of the
transition.  During system suspend the power domain .suspend()
callback executes pm_generic_suspend() for the device, while the
PM domain .suspend_noirq() callback runs pm_generic_suspend_noirq()
for it, stops it and eventually removes power from the PM domain it
belongs to (after all devices in the domain have been stopped and its
subdomains have been powered off).

During system resume the PM domain .resume_noirq() callback
restores power to the PM domain (when executed for it first time),
starts the device and executes pm_generic_resume_noirq() for it,
while the .resume() callback executes pm_generic_resume() for the
device.  Finally, the .complete() callback executes pm_runtime_idle()
for the device which should put it back into the suspended state if
its runtime PM usage count is equal to zero at that time.

The actions carried out during hibernation and resume from it are
analogous to the ones described above.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Kevin Hilman <khilman@ti.com>
(cherry picked from commit 596ba34bcd2978ee9823cc1d84df230576f8ffb9)

Signed-off-by: Simon Horman <horms@verge.net.au>
---
 drivers/base/power/domain.c |  551 +++++++++++++++++++++++++++++++++++++++++--
 include/linux/pm_domain.h   |   12 +
 2 files changed, 548 insertions(+), 15 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index f14ba32..33086e9 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -21,7 +21,7 @@ static struct generic_pm_domain *dev_to_genpd(struct device *dev)
 	if (IS_ERR_OR_NULL(dev->pm_domain))
 		return ERR_PTR(-EINVAL);
 
-	return container_of(dev->pm_domain, struct generic_pm_domain, domain);
+	return pd_to_genpd(dev->pm_domain);
 }
 
 static void genpd_sd_counter_dec(struct generic_pm_domain *genpd)
@@ -46,7 +46,8 @@ static int pm_genpd_poweron(struct generic_pm_domain *genpd)
 		mutex_lock(&genpd->parent->lock);
 	mutex_lock_nested(&genpd->lock, SINGLE_DEPTH_NESTING);
 
-	if (!genpd->power_is_off)
+	if (!genpd->power_is_off
+	    || (genpd->prepared_count > 0 && genpd->suspend_power_off))
 		goto out;
 
 	if (genpd->parent && genpd->parent->power_is_off) {
@@ -155,7 +156,7 @@ static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
 	unsigned int not_suspended;
 	int ret;
 
-	if (genpd->power_is_off)
+	if (genpd->power_is_off || genpd->prepared_count > 0)
 		return 0;
 
 	if (genpd->sd_count > 0)
@@ -260,6 +261,27 @@ static int pm_genpd_runtime_suspend(struct device *dev)
 }
 
 /**
+ * __pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
+ * @dev: Device to resume.
+ * @genpd: PM domain the device belongs to.
+ */
+static void __pm_genpd_runtime_resume(struct device *dev,
+				      struct generic_pm_domain *genpd)
+{
+	struct dev_list_entry *dle;
+
+	list_for_each_entry(dle, &genpd->dev_list, node) {
+		if (dle->dev == dev) {
+			__pm_genpd_restore_device(dle, genpd);
+			break;
+		}
+	}
+
+	if (genpd->start_device)
+		genpd->start_device(dev);
+}
+
+/**
  * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
  * @dev: Device to resume.
  *
@@ -270,7 +292,6 @@ static int pm_genpd_runtime_suspend(struct device *dev)
 static int pm_genpd_runtime_resume(struct device *dev)
 {
 	struct generic_pm_domain *genpd;
-	struct dev_list_entry *dle;
 	int ret;
 
 	dev_dbg(dev, "%s()\n", __func__);
@@ -284,17 +305,7 @@ static int pm_genpd_runtime_resume(struct device *dev)
 		return ret;
 
 	mutex_lock(&genpd->lock);
-
-	list_for_each_entry(dle, &genpd->dev_list, node) {
-		if (dle->dev == dev) {
-			__pm_genpd_restore_device(dle, genpd);
-			break;
-		}
-	}
-
-	if (genpd->start_device)
-		genpd->start_device(dev);
-
+	__pm_genpd_runtime_resume(dev, genpd);
 	mutex_unlock(&genpd->lock);
 
 	return 0;
@@ -303,12 +314,493 @@ static int pm_genpd_runtime_resume(struct device *dev)
 #else
 
 static inline void genpd_power_off_work_fn(struct work_struct *work) {}
+static inline void __pm_genpd_runtime_resume(struct device *dev,
+					     struct generic_pm_domain *genpd) {}
 
 #define pm_genpd_runtime_suspend	NULL
 #define pm_genpd_runtime_resume		NULL
 
 #endif /* CONFIG_PM_RUNTIME */
 
+#ifdef CONFIG_PM_SLEEP
+
+/**
+ * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its parents.
+ * @genpd: PM domain to power off, if possible.
+ *
+ * Check if the given PM domain can be powered off (during system suspend or
+ * hibernation) and do that if so.  Also, in that case propagate to its parent.
+ *
+ * This function is only called in "noirq" stages of system power transitions,
+ * so it need not acquire locks (all of the "noirq" callbacks are executed
+ * sequentially, so it is guaranteed that it will never run twice in parallel).
+ */
+static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd)
+{
+	struct generic_pm_domain *parent = genpd->parent;
+
+	if (genpd->power_is_off)
+		return;
+
+	if (genpd->suspended_count != genpd->device_count || genpd->sd_count > 0)
+		return;
+
+	if (genpd->power_off)
+		genpd->power_off(genpd);
+
+	genpd->power_is_off = true;
+	if (parent) {
+		genpd_sd_counter_dec(parent);
+		pm_genpd_sync_poweroff(parent);
+	}
+}
+
+/**
+ * pm_genpd_prepare - Start power transition of a device in a PM domain.
+ * @dev: Device to start the transition of.
+ *
+ * Start a power transition of a device (during a system-wide power transition)
+ * under the assumption that its pm_domain field points to the domain member of
+ * an object of type struct generic_pm_domain representing a PM domain
+ * consisting of I/O devices.
+ */
+static int pm_genpd_prepare(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	mutex_lock(&genpd->lock);
+
+	if (genpd->prepared_count++ == 0)
+		genpd->suspend_power_off = genpd->power_is_off;
+
+	if (genpd->suspend_power_off) {
+		mutex_unlock(&genpd->lock);
+		return 0;
+	}
+
+	/*
+	 * If the device is in the (runtime) "suspended" state, call
+	 * .start_device() for it, if defined.
+	 */
+	if (pm_runtime_suspended(dev))
+		__pm_genpd_runtime_resume(dev, genpd);
+
+	/*
+	 * Do not check if runtime resume is pending at this point, because it
+	 * has been taken care of already and if pm_genpd_poweron() ran at this
+	 * point as a result of the check, it would deadlock.
+	 */
+	__pm_runtime_disable(dev, false);
+
+	mutex_unlock(&genpd->lock);
+
+	return pm_generic_prepare(dev);
+}
+
+/**
+ * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
+ * @dev: Device to suspend.
+ *
+ * Suspend a device under the assumption that its pm_domain field points to the
+ * domain member of an object of type struct generic_pm_domain representing
+ * a PM domain consisting of I/O devices.
+ */
+static int pm_genpd_suspend(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev);
+}
+
+/**
+ * pm_genpd_suspend_noirq - Late suspend of a device from an I/O PM domain.
+ * @dev: Device to suspend.
+ *
+ * Carry out a late suspend of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a PM domain consisting of I/O devices.
+ */
+static int pm_genpd_suspend_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+	int ret;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	if (genpd->suspend_power_off)
+		return 0;
+
+	ret = pm_generic_suspend_noirq(dev);
+	if (ret)
+		return ret;
+
+	if (genpd->stop_device)
+		genpd->stop_device(dev);
+
+	/*
+	 * Since all of the "noirq" callbacks are executed sequentially, it is
+	 * guaranteed that this function will never run twice in parallel for
+	 * the same PM domain, so it is not necessary to use locking here.
+	 */
+	genpd->suspended_count++;
+	pm_genpd_sync_poweroff(genpd);
+
+	return 0;
+}
+
+/**
+ * pm_genpd_resume_noirq - Early resume of a device from an I/O power domain.
+ * @dev: Device to resume.
+ *
+ * Carry out an early resume of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a power domain consisting of I/O
+ * devices.
+ */
+static int pm_genpd_resume_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	if (genpd->suspend_power_off)
+		return 0;
+
+	/*
+	 * Since all of the "noirq" callbacks are executed sequentially, it is
+	 * guaranteed that this function will never run twice in parallel for
+	 * the same PM domain, so it is not necessary to use locking here.
+	 */
+	pm_genpd_poweron(genpd);
+	genpd->suspended_count--;
+	if (genpd->start_device)
+		genpd->start_device(dev);
+
+	return pm_generic_resume_noirq(dev);
+}
+
+/**
+ * pm_genpd_resume - Resume a device belonging to an I/O power domain.
+ * @dev: Device to resume.
+ *
+ * Resume a device under the assumption that its pm_domain field points to the
+ * domain member of an object of type struct generic_pm_domain representing
+ * a power domain consisting of I/O devices.
+ */
+static int pm_genpd_resume(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : pm_generic_resume(dev);
+}
+
+/**
+ * pm_genpd_freeze - Freeze a device belonging to an I/O power domain.
+ * @dev: Device to freeze.
+ *
+ * Freeze a device under the assumption that its pm_domain field points to the
+ * domain member of an object of type struct generic_pm_domain representing
+ * a power domain consisting of I/O devices.
+ */
+static int pm_genpd_freeze(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev);
+}
+
+/**
+ * pm_genpd_freeze_noirq - Late freeze of a device from an I/O power domain.
+ * @dev: Device to freeze.
+ *
+ * Carry out a late freeze of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a power domain consisting of I/O
+ * devices.
+ */
+static int pm_genpd_freeze_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+	int ret;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	if (genpd->suspend_power_off)
+		return 0;
+
+	ret = pm_generic_freeze_noirq(dev);
+	if (ret)
+		return ret;
+
+	if (genpd->stop_device)
+		genpd->stop_device(dev);
+
+	return 0;
+}
+
+/**
+ * pm_genpd_thaw_noirq - Early thaw of a device from an I/O power domain.
+ * @dev: Device to thaw.
+ *
+ * Carry out an early thaw of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a power domain consisting of I/O
+ * devices.
+ */
+static int pm_genpd_thaw_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	if (genpd->suspend_power_off)
+		return 0;
+
+	if (genpd->start_device)
+		genpd->start_device(dev);
+
+	return pm_generic_thaw_noirq(dev);
+}
+
+/**
+ * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
+ * @dev: Device to thaw.
+ *
+ * Thaw a device under the assumption that its pm_domain field points to the
+ * domain member of an object of type struct generic_pm_domain representing
+ * a power domain consisting of I/O devices.
+ */
+static int pm_genpd_thaw(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev);
+}
+
+/**
+ * pm_genpd_dev_poweroff - Power off a device belonging to an I/O PM domain.
+ * @dev: Device to suspend.
+ *
+ * Power off a device under the assumption that its pm_domain field points to
+ * the domain member of an object of type struct generic_pm_domain representing
+ * a PM domain consisting of I/O devices.
+ */
+static int pm_genpd_dev_poweroff(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : pm_generic_poweroff(dev);
+}
+
+/**
+ * pm_genpd_dev_poweroff_noirq - Late power off of a device from a PM domain.
+ * @dev: Device to suspend.
+ *
+ * Carry out a late powering off of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a PM domain consisting of I/O devices.
+ */
+static int pm_genpd_dev_poweroff_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+	int ret;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	if (genpd->suspend_power_off)
+		return 0;
+
+	ret = pm_generic_poweroff_noirq(dev);
+	if (ret)
+		return ret;
+
+	if (genpd->stop_device)
+		genpd->stop_device(dev);
+
+	/*
+	 * Since all of the "noirq" callbacks are executed sequentially, it is
+	 * guaranteed that this function will never run twice in parallel for
+	 * the same PM domain, so it is not necessary to use locking here.
+	 */
+	genpd->suspended_count++;
+	pm_genpd_sync_poweroff(genpd);
+
+	return 0;
+}
+
+/**
+ * pm_genpd_restore_noirq - Early restore of a device from an I/O power domain.
+ * @dev: Device to resume.
+ *
+ * Carry out an early restore of a device under the assumption that its
+ * pm_domain field points to the domain member of an object of type
+ * struct generic_pm_domain representing a power domain consisting of I/O
+ * devices.
+ */
+static int pm_genpd_restore_noirq(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	/*
+	 * Since all of the "noirq" callbacks are executed sequentially, it is
+	 * guaranteed that this function will never run twice in parallel for
+	 * the same PM domain, so it is not necessary to use locking here.
+	 */
+	genpd->power_is_off = true;
+	if (genpd->suspend_power_off) {
+		/*
+		 * The boot kernel might put the domain into the power on state,
+		 * so make sure it really is powered off.
+		 */
+		if (genpd->power_off)
+			genpd->power_off(genpd);
+		return 0;
+	}
+
+	pm_genpd_poweron(genpd);
+	genpd->suspended_count--;
+	if (genpd->start_device)
+		genpd->start_device(dev);
+
+	return pm_generic_restore_noirq(dev);
+}
+
+/**
+ * pm_genpd_restore - Restore a device belonging to an I/O power domain.
+ * @dev: Device to resume.
+ *
+ * Restore a device under the assumption that its pm_domain field points to the
+ * domain member of an object of type struct generic_pm_domain representing
+ * a power domain consisting of I/O devices.
+ */
+static int pm_genpd_restore(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return -EINVAL;
+
+	return genpd->suspend_power_off ? 0 : pm_generic_restore(dev);
+}
+
+/**
+ * pm_genpd_complete - Complete power transition of a device in a power domain.
+ * @dev: Device to complete the transition of.
+ *
+ * Complete a power transition of a device (during a system-wide power
+ * transition) under the assumption that its pm_domain field points to the
+ * domain member of an object of type struct generic_pm_domain representing
+ * a power domain consisting of I/O devices.
+ */
+static void pm_genpd_complete(struct device *dev)
+{
+	struct generic_pm_domain *genpd;
+	bool run_complete;
+
+	dev_dbg(dev, "%s()\n", __func__);
+
+	genpd = dev_to_genpd(dev);
+	if (IS_ERR(genpd))
+		return;
+
+	mutex_lock(&genpd->lock);
+
+	run_complete = !genpd->suspend_power_off;
+	if (--genpd->prepared_count == 0)
+		genpd->suspend_power_off = false;
+
+	mutex_unlock(&genpd->lock);
+
+	if (run_complete) {
+		pm_generic_complete(dev);
+		pm_runtime_enable(dev);
+	}
+}
+
+#else
+
+#define pm_genpd_prepare		NULL
+#define pm_genpd_suspend		NULL
+#define pm_genpd_suspend_noirq		NULL
+#define pm_genpd_resume_noirq		NULL
+#define pm_genpd_resume			NULL
+#define pm_genpd_freeze			NULL
+#define pm_genpd_freeze_noirq		NULL
+#define pm_genpd_thaw_noirq		NULL
+#define pm_genpd_thaw			NULL
+#define pm_genpd_dev_poweroff_noirq	NULL
+#define pm_genpd_dev_poweroff		NULL
+#define pm_genpd_restore_noirq		NULL
+#define pm_genpd_restore		NULL
+#define pm_genpd_complete		NULL
+
+#endif /* CONFIG_PM_SLEEP */
+
 /**
  * pm_genpd_add_device - Add a device to an I/O PM domain.
  * @genpd: PM domain to add the device to.
@@ -331,6 +823,11 @@ int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
 		goto out;
 	}
 
+	if (genpd->prepared_count > 0) {
+		ret = -EAGAIN;
+		goto out;
+	}
+
 	list_for_each_entry(dle, &genpd->dev_list, node)
 		if (dle->dev == dev) {
 			ret = -EINVAL;
@@ -346,6 +843,7 @@ int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
 	dle->dev = dev;
 	dle->need_restore = false;
 	list_add_tail(&dle->node, &genpd->dev_list);
+	genpd->device_count++;
 
 	spin_lock_irq(&dev->power.lock);
 	dev->pm_domain = &genpd->domain;
@@ -375,6 +873,11 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
 
 	mutex_lock(&genpd->lock);
 
+	if (genpd->prepared_count > 0) {
+		ret = -EAGAIN;
+		goto out;
+	}
+
 	list_for_each_entry(dle, &genpd->dev_list, node) {
 		if (dle->dev != dev)
 			continue;
@@ -383,6 +886,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
 		dev->pm_domain = NULL;
 		spin_unlock_irq(&dev->power.lock);
 
+		genpd->device_count--;
 		list_del(&dle->node);
 		kfree(dle);
 
@@ -390,6 +894,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
 		break;
 	}
 
+ out:
 	mutex_unlock(&genpd->lock);
 
 	return ret;
@@ -498,7 +1003,23 @@ void pm_genpd_init(struct generic_pm_domain *genpd,
 	genpd->in_progress = 0;
 	genpd->sd_count = 0;
 	genpd->power_is_off = is_off;
+	genpd->device_count = 0;
+	genpd->suspended_count = 0;
 	genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
 	genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
 	genpd->domain.ops.runtime_idle = pm_generic_runtime_idle;
+	genpd->domain.ops.prepare = pm_genpd_prepare;
+	genpd->domain.ops.suspend = pm_genpd_suspend;
+	genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
+	genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
+	genpd->domain.ops.resume = pm_genpd_resume;
+	genpd->domain.ops.freeze = pm_genpd_freeze;
+	genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
+	genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
+	genpd->domain.ops.thaw = pm_genpd_thaw;
+	genpd->domain.ops.poweroff = pm_genpd_dev_poweroff;
+	genpd->domain.ops.poweroff_noirq = pm_genpd_dev_poweroff_noirq;
+	genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
+	genpd->domain.ops.restore = pm_genpd_restore;
+	genpd->domain.ops.complete = pm_genpd_complete;
 }
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index b1a22c6..7961b0d 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -11,6 +11,9 @@
 
 #include <linux/device.h>
 
+#define GPD_IN_SUSPEND	1
+#define GPD_POWER_OFF	2
+
 struct dev_power_governor {
 	bool (*power_down_ok)(struct dev_pm_domain *domain);
 };
@@ -27,12 +30,21 @@ struct generic_pm_domain {
 	unsigned int in_progress;	/* Number of devices being suspended now */
 	unsigned int sd_count;	/* Number of subdomains with power "on" */
 	bool power_is_off;	/* Whether or not power has been removed */
+	unsigned int device_count;	/* Number of devices */
+	unsigned int suspended_count;	/* System suspend device counter */
+	unsigned int prepared_count;	/* Suspend counter of prepared devices */
+	bool suspend_power_off;	/* Power status before system suspend */
 	int (*power_off)(struct generic_pm_domain *domain);
 	int (*power_on)(struct generic_pm_domain *domain);
 	int (*start_device)(struct device *dev);
 	int (*stop_device)(struct device *dev);
 };
 
+static inline struct generic_pm_domain *pd_to_genpd(struct dev_pm_domain *pd)
+{
+	return container_of(pd, struct generic_pm_domain, domain);
+}
+
 struct dev_list_entry {
 	struct list_head node;
 	struct device *dev;
-- 
1.7.10.1.362.g242cab3