summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/sleep.c
blob: 7a2e4d45b266724c536ce87361c7eb1a2a6e007c (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
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
/*
 * sleep.c - ACPI sleep support.
 *
 * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
 * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
 * Copyright (c) 2000-2003 Patrick Mochel
 * Copyright (c) 2003 Open Source Development Lab
 *
 * This file is released under the GPLv2.
 *
 */

#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/dmi.h>
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/suspend.h>
#include <linux/reboot.h>
#include <linux/acpi.h>
#include <linux/module.h>
#include <linux/syscore_ops.h>
#include <asm/io.h>
#include <trace/events/power.h>

#include "internal.h"
#include "sleep.h"

/*
 * Some HW-full platforms do not have _S5, so they may need
 * to leverage efi power off for a shutdown.
 */
bool acpi_no_s5;
static u8 sleep_states[ACPI_S_STATE_COUNT];

static void acpi_sleep_tts_switch(u32 acpi_state)
{
	acpi_status status;

	status = acpi_execute_simple_method(NULL, "\\_TTS", acpi_state);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		/*
		 * OS can't evaluate the _TTS object correctly. Some warning
		 * message will be printed. But it won't break anything.
		 */
		printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
	}
}

static int tts_notify_reboot(struct notifier_block *this,
			unsigned long code, void *x)
{
	acpi_sleep_tts_switch(ACPI_STATE_S5);
	return NOTIFY_DONE;
}

static struct notifier_block tts_notifier = {
	.notifier_call	= tts_notify_reboot,
	.next		= NULL,
	.priority	= 0,
};

static int acpi_sleep_prepare(u32 acpi_state)
{
#ifdef CONFIG_ACPI_SLEEP
	/* do we have a wakeup address for S2 and S3? */
	if (acpi_state == ACPI_STATE_S3) {
		if (!acpi_wakeup_address)
			return -EFAULT;
		acpi_set_waking_vector(acpi_wakeup_address);

	}
	ACPI_FLUSH_CPU_CACHE();
#endif
	printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
		acpi_state);
	acpi_enable_wakeup_devices(acpi_state);
	acpi_enter_sleep_state_prep(acpi_state);
	return 0;
}

static bool acpi_sleep_state_supported(u8 sleep_state)
{
	acpi_status status;
	u8 type_a, type_b;

	status = acpi_get_sleep_type_data(sleep_state, &type_a, &type_b);
	return ACPI_SUCCESS(status) && (!acpi_gbl_reduced_hardware
		|| (acpi_gbl_FADT.sleep_control.address
			&& acpi_gbl_FADT.sleep_status.address));
}

#ifdef CONFIG_ACPI_SLEEP
static u32 acpi_target_sleep_state = ACPI_STATE_S0;

u32 acpi_target_system_state(void)
{
	return acpi_target_sleep_state;
}
EXPORT_SYMBOL_GPL(acpi_target_system_state);

static bool pwr_btn_event_pending;

/*
 * The ACPI specification wants us to save NVS memory regions during hibernation
 * and to restore them during the subsequent resume.  Windows does that also for
 * suspend to RAM.  However, it is known that this mechanism does not work on
 * all machines, so we allow the user to disable it with the help of the
 * 'acpi_sleep=nonvs' kernel command line option.
 */
static bool nvs_nosave;

void __init acpi_nvs_nosave(void)
{
	nvs_nosave = true;
}

/*
 * The ACPI specification wants us to save NVS memory regions during hibernation
 * but says nothing about saving NVS during S3.  Not all versions of Windows
 * save NVS on S3 suspend either, and it is clear that not all systems need
 * NVS to be saved at S3 time.  To improve suspend/resume time, allow the
 * user to disable saving NVS on S3 if their system does not require it, but
 * continue to save/restore NVS for S4 as specified.
 */
static bool nvs_nosave_s3;

void __init acpi_nvs_nosave_s3(void)
{
	nvs_nosave_s3 = true;
}

/*
 * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
 * user to request that behavior by using the 'acpi_old_suspend_ordering'
 * kernel command line option that causes the following variable to be set.
 */
static bool old_suspend_ordering;

void __init acpi_old_suspend_ordering(void)
{
	old_suspend_ordering = true;
}

static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
{
	acpi_old_suspend_ordering();
	return 0;
}

static int __init init_nvs_nosave(const struct dmi_system_id *d)
{
	acpi_nvs_nosave();
	return 0;
}

static struct dmi_system_id acpisleep_dmi_table[] __initdata = {
	{
	.callback = init_old_suspend_ordering,
	.ident = "Abit KN9 (nForce4 variant)",
	.matches = {
		DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
		DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
		},
	},
	{
	.callback = init_old_suspend_ordering,
	.ident = "HP xw4600 Workstation",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
		DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
		},
	},
	{
	.callback = init_old_suspend_ordering,
	.ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
	.matches = {
		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
		DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
		},
	},
	{
	.callback = init_old_suspend_ordering,
	.ident = "Panasonic CF51-2L",
	.matches = {
		DMI_MATCH(DMI_BOARD_VENDOR,
				"Matsushita Electric Industrial Co.,Ltd."),
		DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VGN-FW41E_H",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW41E_H"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VGN-FW21E",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21E"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VGN-FW21M",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21M"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VPCEB17FX",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB17FX"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VGN-SR11M",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Everex StepNote Series",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
		DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VPCEB1Z1E",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VGN-NW130D",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VPCCW29FX",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VPCCW29FX"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Averatec AV1020-ED2",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
		DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
		},
	},
	{
	.callback = init_old_suspend_ordering,
	.ident = "Asus A8N-SLI DELUXE",
	.matches = {
		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
		DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI DELUXE"),
		},
	},
	{
	.callback = init_old_suspend_ordering,
	.ident = "Asus A8N-SLI Premium",
	.matches = {
		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
		DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI Premium"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VGN-SR26GN_P",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR26GN_P"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VPCEB1S1E",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1S1E"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Sony Vaio VGN-FW520F",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW520F"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Asus K54C",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
		DMI_MATCH(DMI_PRODUCT_NAME, "K54C"),
		},
	},
	{
	.callback = init_nvs_nosave,
	.ident = "Asus K54HR",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
		DMI_MATCH(DMI_PRODUCT_NAME, "K54HR"),
		},
	},
	{},
};

static void __init acpi_sleep_dmi_check(void)
{
	int year;

	if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year >= 2012)
		acpi_nvs_nosave_s3();

	dmi_check_system(acpisleep_dmi_table);
}

/**
 * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
 */
static int acpi_pm_freeze(void)
{
	acpi_disable_all_gpes();
	acpi_os_wait_events_complete();
	acpi_ec_block_transactions();
	return 0;
}

/**
 * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
 */
static int acpi_pm_pre_suspend(void)
{
	acpi_pm_freeze();
	return suspend_nvs_save();
}

/**
 *	__acpi_pm_prepare - Prepare the platform to enter the target state.
 *
 *	If necessary, set the firmware waking vector and do arch-specific
 *	nastiness to get the wakeup code to the waking vector.
 */
static int __acpi_pm_prepare(void)
{
	int error = acpi_sleep_prepare(acpi_target_sleep_state);
	if (error)
		acpi_target_sleep_state = ACPI_STATE_S0;

	return error;
}

/**
 *	acpi_pm_prepare - Prepare the platform to enter the target sleep
 *		state and disable the GPEs.
 */
static int acpi_pm_prepare(void)
{
	int error = __acpi_pm_prepare();
	if (!error)
		error = acpi_pm_pre_suspend();

	return error;
}

static int find_powerf_dev(struct device *dev, void *data)
{
	struct acpi_device *device = to_acpi_device(dev);
	const char *hid = acpi_device_hid(device);

	return !strcmp(hid, ACPI_BUTTON_HID_POWERF);
}

/**
 *	acpi_pm_finish - Instruct the platform to leave a sleep state.
 *
 *	This is called after we wake back up (or if entering the sleep state
 *	failed).
 */
static void acpi_pm_finish(void)
{
	struct device *pwr_btn_dev;
	u32 acpi_state = acpi_target_sleep_state;

	acpi_ec_unblock_transactions();
	suspend_nvs_free();

	if (acpi_state == ACPI_STATE_S0)
		return;

	printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
		acpi_state);
	acpi_disable_wakeup_devices(acpi_state);
	acpi_leave_sleep_state(acpi_state);

	/* reset firmware waking vector */
	acpi_set_waking_vector(0);

	acpi_target_sleep_state = ACPI_STATE_S0;

	acpi_resume_power_resources();

	/* If we were woken with the fixed power button, provide a small
	 * hint to userspace in the form of a wakeup event on the fixed power
	 * button device (if it can be found).
	 *
	 * We delay the event generation til now, as the PM layer requires
	 * timekeeping to be running before we generate events. */
	if (!pwr_btn_event_pending)
		return;

	pwr_btn_event_pending = false;
	pwr_btn_dev = bus_find_device(&acpi_bus_type, NULL, NULL,
				      find_powerf_dev);
	if (pwr_btn_dev) {
		pm_wakeup_event(pwr_btn_dev, 0);
		put_device(pwr_btn_dev);
	}
}

/**
 * acpi_pm_start - Start system PM transition.
 */
static void acpi_pm_start(u32 acpi_state)
{
	acpi_target_sleep_state = acpi_state;
	acpi_sleep_tts_switch(acpi_target_sleep_state);
	acpi_scan_lock_acquire();
}

/**
 * acpi_pm_end - Finish up system PM transition.
 */
static void acpi_pm_end(void)
{
	acpi_scan_lock_release();
	/*
	 * This is necessary in case acpi_pm_finish() is not called during a
	 * failing transition to a sleep state.
	 */
	acpi_target_sleep_state = ACPI_STATE_S0;
	acpi_sleep_tts_switch(acpi_target_sleep_state);
}
#else /* !CONFIG_ACPI_SLEEP */
#define acpi_target_sleep_state	ACPI_STATE_S0
static inline void acpi_sleep_dmi_check(void) {}
#endif /* CONFIG_ACPI_SLEEP */

#ifdef CONFIG_SUSPEND
static u32 acpi_suspend_states[] = {
	[PM_SUSPEND_ON] = ACPI_STATE_S0,
	[PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
	[PM_SUSPEND_MEM] = ACPI_STATE_S3,
	[PM_SUSPEND_MAX] = ACPI_STATE_S5
};

/**
 *	acpi_suspend_begin - Set the target system sleep state to the state
 *		associated with given @pm_state, if supported.
 */
static int acpi_suspend_begin(suspend_state_t pm_state)
{
	u32 acpi_state = acpi_suspend_states[pm_state];
	int error;

	error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc();
	if (error)
		return error;

	if (!sleep_states[acpi_state]) {
		pr_err("ACPI does not support sleep state S%u\n", acpi_state);
		return -ENOSYS;
	}
	if (acpi_state > ACPI_STATE_S1)
		pm_set_suspend_via_firmware();

	acpi_pm_start(acpi_state);
	return 0;
}

/**
 *	acpi_suspend_enter - Actually enter a sleep state.
 *	@pm_state: ignored
 *
 *	Flush caches and go to sleep. For STR we have to call arch-specific
 *	assembly, which in turn call acpi_enter_sleep_state().
 *	It's unfortunate, but it works. Please fix if you're feeling frisky.
 */
static int acpi_suspend_enter(suspend_state_t pm_state)
{
	acpi_status status = AE_OK;
	u32 acpi_state = acpi_target_sleep_state;
	int error;

	ACPI_FLUSH_CPU_CACHE();

	trace_suspend_resume(TPS("acpi_suspend"), acpi_state, true);
	switch (acpi_state) {
	case ACPI_STATE_S1:
		barrier();
		status = acpi_enter_sleep_state(acpi_state);
		break;

	case ACPI_STATE_S3:
		if (!acpi_suspend_lowlevel)
			return -ENOSYS;
		error = acpi_suspend_lowlevel();
		if (error)
			return error;
		pr_info(PREFIX "Low-level resume complete\n");
		pm_set_resume_via_firmware();
		break;
	}
	trace_suspend_resume(TPS("acpi_suspend"), acpi_state, false);

	/* This violates the spec but is required for bug compatibility. */
	acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);

	/* Reprogram control registers */
	acpi_leave_sleep_state_prep(acpi_state);

	/* ACPI 3.0 specs (P62) says that it's the responsibility
	 * of the OSPM to clear the status bit [ implying that the
	 * POWER_BUTTON event should not reach userspace ]
	 *
	 * However, we do generate a small hint for userspace in the form of
	 * a wakeup event. We flag this condition for now and generate the
	 * event later, as we're currently too early in resume to be able to
	 * generate wakeup events.
	 */
	if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3)) {
		acpi_event_status pwr_btn_status = ACPI_EVENT_FLAG_DISABLED;

		acpi_get_event_status(ACPI_EVENT_POWER_BUTTON, &pwr_btn_status);

		if (pwr_btn_status & ACPI_EVENT_FLAG_SET) {
			acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
			/* Flag for later */
			pwr_btn_event_pending = true;
		}
	}

	/*
	 * Disable and clear GPE status before interrupt is enabled. Some GPEs
	 * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
	 * acpi_leave_sleep_state will reenable specific GPEs later
	 */
	acpi_disable_all_gpes();
	/* Allow EC transactions to happen. */
	acpi_ec_unblock_transactions_early();

	suspend_nvs_restore();

	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}

static int acpi_suspend_state_valid(suspend_state_t pm_state)
{
	u32 acpi_state;

	switch (pm_state) {
	case PM_SUSPEND_ON:
	case PM_SUSPEND_STANDBY:
	case PM_SUSPEND_MEM:
		acpi_state = acpi_suspend_states[pm_state];

		return sleep_states[acpi_state];
	default:
		return 0;
	}
}

static const struct platform_suspend_ops acpi_suspend_ops = {
	.valid = acpi_suspend_state_valid,
	.begin = acpi_suspend_begin,
	.prepare_late = acpi_pm_prepare,
	.enter = acpi_suspend_enter,
	.wake = acpi_pm_finish,
	.end = acpi_pm_end,
};

/**
 *	acpi_suspend_begin_old - Set the target system sleep state to the
 *		state associated with given @pm_state, if supported, and
 *		execute the _PTS control method.  This function is used if the
 *		pre-ACPI 2.0 suspend ordering has been requested.
 */
static int acpi_suspend_begin_old(suspend_state_t pm_state)
{
	int error = acpi_suspend_begin(pm_state);
	if (!error)
		error = __acpi_pm_prepare();

	return error;
}

/*
 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 * been requested.
 */
static const struct platform_suspend_ops acpi_suspend_ops_old = {
	.valid = acpi_suspend_state_valid,
	.begin = acpi_suspend_begin_old,
	.prepare_late = acpi_pm_pre_suspend,
	.enter = acpi_suspend_enter,
	.wake = acpi_pm_finish,
	.end = acpi_pm_end,
	.recover = acpi_pm_finish,
};

static int acpi_freeze_begin(void)
{
	acpi_scan_lock_acquire();
	return 0;
}

static int acpi_freeze_prepare(void)
{
	acpi_enable_wakeup_devices(ACPI_STATE_S0);
	acpi_enable_all_wakeup_gpes();
	acpi_os_wait_events_complete();
	if (acpi_sci_irq_valid())
		enable_irq_wake(acpi_sci_irq);
	return 0;
}

static void acpi_freeze_restore(void)
{
	acpi_disable_wakeup_devices(ACPI_STATE_S0);
	if (acpi_sci_irq_valid())
		disable_irq_wake(acpi_sci_irq);
	acpi_enable_all_runtime_gpes();
}

static void acpi_freeze_end(void)
{
	acpi_scan_lock_release();
}

static const struct platform_freeze_ops acpi_freeze_ops = {
	.begin = acpi_freeze_begin,
	.prepare = acpi_freeze_prepare,
	.restore = acpi_freeze_restore,
	.end = acpi_freeze_end,
};

static void acpi_sleep_suspend_setup(void)
{
	int i;

	for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++)
		if (acpi_sleep_state_supported(i))
			sleep_states[i] = 1;

	suspend_set_ops(old_suspend_ordering ?
		&acpi_suspend_ops_old : &acpi_suspend_ops);
	freeze_set_ops(&acpi_freeze_ops);
}

#else /* !CONFIG_SUSPEND */
static inline void acpi_sleep_suspend_setup(void) {}
#endif /* !CONFIG_SUSPEND */

#ifdef CONFIG_PM_SLEEP
static u32 saved_bm_rld;

static int  acpi_save_bm_rld(void)
{
	acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
	return 0;
}

static void  acpi_restore_bm_rld(void)
{
	u32 resumed_bm_rld = 0;

	acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
	if (resumed_bm_rld == saved_bm_rld)
		return;

	acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
}

static struct syscore_ops acpi_sleep_syscore_ops = {
	.suspend = acpi_save_bm_rld,
	.resume = acpi_restore_bm_rld,
};

void acpi_sleep_syscore_init(void)
{
	register_syscore_ops(&acpi_sleep_syscore_ops);
}
#else
static inline void acpi_sleep_syscore_init(void) {}
#endif /* CONFIG_PM_SLEEP */

#ifdef CONFIG_HIBERNATION
static unsigned long s4_hardware_signature;
static struct acpi_table_facs *facs;
static bool nosigcheck;

void __init acpi_no_s4_hw_signature(void)
{
	nosigcheck = true;
}

static int acpi_hibernation_begin(void)
{
	int error;

	error = nvs_nosave ? 0 : suspend_nvs_alloc();
	if (!error)
		acpi_pm_start(ACPI_STATE_S4);

	return error;
}

static int acpi_hibernation_enter(void)
{
	acpi_status status = AE_OK;

	ACPI_FLUSH_CPU_CACHE();

	/* This shouldn't return.  If it returns, we have a problem */
	status = acpi_enter_sleep_state(ACPI_STATE_S4);
	/* Reprogram control registers */
	acpi_leave_sleep_state_prep(ACPI_STATE_S4);

	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
}

static void acpi_hibernation_leave(void)
{
	pm_set_resume_via_firmware();
	/*
	 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
	 * enable it here.
	 */
	acpi_enable();
	/* Reprogram control registers */
	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
	/* Check the hardware signature */
	if (facs && s4_hardware_signature != facs->hardware_signature)
		pr_crit("ACPI: Hardware changed while hibernated, success doubtful!\n");
	/* Restore the NVS memory area */
	suspend_nvs_restore();
	/* Allow EC transactions to happen. */
	acpi_ec_unblock_transactions_early();
}

static void acpi_pm_thaw(void)
{
	acpi_ec_unblock_transactions();
	acpi_enable_all_runtime_gpes();
}

static const struct platform_hibernation_ops acpi_hibernation_ops = {
	.begin = acpi_hibernation_begin,
	.end = acpi_pm_end,
	.pre_snapshot = acpi_pm_prepare,
	.finish = acpi_pm_finish,
	.prepare = acpi_pm_prepare,
	.enter = acpi_hibernation_enter,
	.leave = acpi_hibernation_leave,
	.pre_restore = acpi_pm_freeze,
	.restore_cleanup = acpi_pm_thaw,
};

/**
 *	acpi_hibernation_begin_old - Set the target system sleep state to
 *		ACPI_STATE_S4 and execute the _PTS control method.  This
 *		function is used if the pre-ACPI 2.0 suspend ordering has been
 *		requested.
 */
static int acpi_hibernation_begin_old(void)
{
	int error;
	/*
	 * The _TTS object should always be evaluated before the _PTS object.
	 * When the old_suspended_ordering is true, the _PTS object is
	 * evaluated in the acpi_sleep_prepare.
	 */
	acpi_sleep_tts_switch(ACPI_STATE_S4);

	error = acpi_sleep_prepare(ACPI_STATE_S4);

	if (!error) {
		if (!nvs_nosave)
			error = suspend_nvs_alloc();
		if (!error) {
			acpi_target_sleep_state = ACPI_STATE_S4;
			acpi_scan_lock_acquire();
		}
	}
	return error;
}

/*
 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 * been requested.
 */
static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
	.begin = acpi_hibernation_begin_old,
	.end = acpi_pm_end,
	.pre_snapshot = acpi_pm_pre_suspend,
	.prepare = acpi_pm_freeze,
	.finish = acpi_pm_finish,
	.enter = acpi_hibernation_enter,
	.leave = acpi_hibernation_leave,
	.pre_restore = acpi_pm_freeze,
	.restore_cleanup = acpi_pm_thaw,
	.recover = acpi_pm_finish,
};

static void acpi_sleep_hibernate_setup(void)
{
	if (!acpi_sleep_state_supported(ACPI_STATE_S4))
		return;

	hibernation_set_ops(old_suspend_ordering ?
			&acpi_hibernation_ops_old : &acpi_hibernation_ops);
	sleep_states[ACPI_STATE_S4] = 1;
	if (nosigcheck)
		return;

	acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
	if (facs)
		s4_hardware_signature = facs->hardware_signature;
}
#else /* !CONFIG_HIBERNATION */
static inline void acpi_sleep_hibernate_setup(void) {}
#endif /* !CONFIG_HIBERNATION */

static void acpi_power_off_prepare(void)
{
	/* Prepare to power off the system */
	acpi_sleep_prepare(ACPI_STATE_S5);
	acpi_disable_all_gpes();
	acpi_os_wait_events_complete();
}

static void acpi_power_off(void)
{
	/* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
	printk(KERN_DEBUG "%s called\n", __func__);
	local_irq_disable();
	acpi_enter_sleep_state(ACPI_STATE_S5);
}

int __init acpi_sleep_init(void)
{
	char supported[ACPI_S_STATE_COUNT * 3 + 1];
	char *pos = supported;
	int i;

	acpi_sleep_dmi_check();

	sleep_states[ACPI_STATE_S0] = 1;

	acpi_sleep_syscore_init();
	acpi_sleep_suspend_setup();
	acpi_sleep_hibernate_setup();

	if (acpi_sleep_state_supported(ACPI_STATE_S5)) {
		sleep_states[ACPI_STATE_S5] = 1;
		pm_power_off_prepare = acpi_power_off_prepare;
		pm_power_off = acpi_power_off;
	} else {
		acpi_no_s5 = true;
	}

	supported[0] = 0;
	for (i = 0; i < ACPI_S_STATE_COUNT; i++) {
		if (sleep_states[i])
			pos += sprintf(pos, " S%d", i);
	}
	pr_info(PREFIX "(supports%s)\n", supported);

	/*
	 * Register the tts_notifier to reboot notifier list so that the _TTS
	 * object can also be evaluated when the system enters S5.
	 */
	register_reboot_notifier(&tts_notifier);
	return 0;
}