summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/sleep.c
blob: d6a8cd14de2e824ddb15563aa625fa1d5236ea5a (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
/*
 * 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/suspend.h>
#include <linux/reboot.h>

#include <asm/io.h>

#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

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

static u8 sleep_states[ACPI_S_STATE_COUNT];

static void acpi_sleep_tts_switch(u32 acpi_state)
{
	union acpi_object in_arg = { ACPI_TYPE_INTEGER };
	struct acpi_object_list arg_list = { 1, &in_arg };
	acpi_status status = AE_OK;

	in_arg.integer.value = acpi_state;
	status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
	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_firmware_waking_vector(
				(acpi_physical_address)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;
}

#ifdef CONFIG_ACPI_SLEEP
static u32 acpi_target_sleep_state = ACPI_STATE_S0;

/*
 * 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;
}

/*
 * 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;
}

/**
 * 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(NULL);
	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;
}

/**
 *	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)
{
	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_firmware_waking_vector((acpi_physical_address) 0);

	acpi_target_sleep_state = ACPI_STATE_S0;
}

/**
 *	acpi_pm_end - Finish up suspend sequence.
 */
static void acpi_pm_end(void)
{
	/*
	 * 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
#endif /* CONFIG_ACPI_SLEEP */

#ifdef CONFIG_SUSPEND
extern void do_suspend_lowlevel(void);

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 = 0;

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

	if (sleep_states[acpi_state]) {
		acpi_target_sleep_state = acpi_state;
		acpi_sleep_tts_switch(acpi_target_sleep_state);
	} else {
		printk(KERN_ERR "ACPI does not support this state: %d\n",
			pm_state);
		error = -ENOSYS;
	}
	return error;
}

/**
 *	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;
	unsigned long flags = 0;
	u32 acpi_state = acpi_target_sleep_state;

	ACPI_FLUSH_CPU_CACHE();

	/* Do arch specific saving of state. */
	if (acpi_state == ACPI_STATE_S3) {
		int error = acpi_save_state_mem();

		if (error)
			return error;
	}

	local_irq_save(flags);
	switch (acpi_state) {
	case ACPI_STATE_S1:
		barrier();
		status = acpi_enter_sleep_state(acpi_state);
		break;

	case ACPI_STATE_S3:
		do_suspend_lowlevel();
		break;
	}

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

	/* Reprogram control registers and execute _BFS */
	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 ]
	 */
	if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
		acpi_clear_event(ACPI_EVENT_POWER_BUTTON);

	/*
	 * 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();

	local_irq_restore(flags);
	printk(KERN_DEBUG "Back to C!\n");

	/* restore processor state */
	if (acpi_state == ACPI_STATE_S3)
		acpi_restore_state_mem();

	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 __init init_old_suspend_ordering(const struct dmi_system_id *d)
{
	old_suspend_ordering = true;
	return 0;
}

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

static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
	{
	.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-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 = "Averatec AV1020-ED2",
	.matches = {
		DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
		DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
		},
	},
	{},
};
#endif /* CONFIG_SUSPEND */

#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_target_sleep_state = ACPI_STATE_S4;
		acpi_sleep_tts_switch(acpi_target_sleep_state);
	}

	return error;
}

static int acpi_hibernation_enter(void)
{
	acpi_status status = AE_OK;
	unsigned long flags = 0;

	ACPI_FLUSH_CPU_CACHE();

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

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

static void acpi_hibernation_leave(void)
{
	/*
	 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
	 * enable it here.
	 */
	acpi_enable();
	/* Reprogram control registers and execute _BFS */
	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
	/* Check the hardware signature */
	if (facs && s4_hardware_signature != facs->hardware_signature) {
		printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
			"cannot resume!\n");
		panic("ACPI S4 hardware signature mismatch");
	}
	/* 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;
	}
	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,
};
#endif /* CONFIG_HIBERNATION */

int acpi_suspend(u32 acpi_state)
{
	suspend_state_t states[] = {
		[1] = PM_SUSPEND_STANDBY,
		[3] = PM_SUSPEND_MEM,
		[5] = PM_SUSPEND_MAX
	};

	if (acpi_state < 6 && states[acpi_state])
		return pm_suspend(states[acpi_state]);
	if (acpi_state == 4)
		return hibernate();
	return -EINVAL;
}

#ifdef CONFIG_PM_OPS
/**
 *	acpi_pm_device_sleep_state - return preferred power state of ACPI device
 *		in the system sleep state given by %acpi_target_sleep_state
 *	@dev: device to examine; its driver model wakeup flags control
 *		whether it should be able to wake up the system
 *	@d_min_p: used to store the upper limit of allowed states range
 *	Return value: preferred power state of the device on success, -ENODEV on
 *		failure (ie. if there's no 'struct acpi_device' for @dev)
 *
 *	Find the lowest power (highest number) ACPI device power state that
 *	device @dev can be in while the system is in the sleep state represented
 *	by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
 *	able to wake up the system from this sleep state.  If @d_min_p is set,
 *	the highest power (lowest number) device power state of @dev allowed
 *	in this system sleep state is stored at the location pointed to by it.
 *
 *	The caller must ensure that @dev is valid before using this function.
 *	The caller is also responsible for figuring out if the device is
 *	supposed to be able to wake up the system and passing this information
 *	via @wake.
 */

int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
{
	acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
	struct acpi_device *adev;
	char acpi_method[] = "_SxD";
	unsigned long long d_min, d_max;

	if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
		printk(KERN_DEBUG "ACPI handle has no context!\n");
		return -ENODEV;
	}

	acpi_method[2] = '0' + acpi_target_sleep_state;
	/*
	 * If the sleep state is S0, we will return D3, but if the device has
	 * _S0W, we will use the value from _S0W
	 */
	d_min = ACPI_STATE_D0;
	d_max = ACPI_STATE_D3;

	/*
	 * If present, _SxD methods return the minimum D-state (highest power
	 * state) we can use for the corresponding S-states.  Otherwise, the
	 * minimum D-state is D0 (ACPI 3.x).
	 *
	 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
	 * provided -- that's our fault recovery, we ignore retval.
	 */
	if (acpi_target_sleep_state > ACPI_STATE_S0)
		acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);

	/*
	 * If _PRW says we can wake up the system from the target sleep state,
	 * the D-state returned by _SxD is sufficient for that (we assume a
	 * wakeup-aware driver if wake is set).  Still, if _SxW exists
	 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
	 * can wake the system.  _S0W may be valid, too.
	 */
	if (acpi_target_sleep_state == ACPI_STATE_S0 ||
	    (device_may_wakeup(dev) &&
	     adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
		acpi_status status;

		acpi_method[3] = 'W';
		status = acpi_evaluate_integer(handle, acpi_method, NULL,
						&d_max);
		if (ACPI_FAILURE(status)) {
			if (acpi_target_sleep_state != ACPI_STATE_S0 ||
			    status != AE_NOT_FOUND)
				d_max = d_min;
		} else if (d_max < d_min) {
			/* Warn the user of the broken DSDT */
			printk(KERN_WARNING "ACPI: Wrong value from %s\n",
				acpi_method);
			/* Sanitize it */
			d_min = d_max;
		}
	}

	if (d_min_p)
		*d_min_p = d_min;
	return d_max;
}
#endif /* CONFIG_PM_OPS */

#ifdef CONFIG_PM_SLEEP
/**
 *	acpi_pm_device_sleep_wake - enable or disable the system wake-up
 *                                  capability of given device
 *	@dev: device to handle
 *	@enable: 'true' - enable, 'false' - disable the wake-up capability
 */
int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
{
	acpi_handle handle;
	struct acpi_device *adev;
	int error;

	if (!device_can_wakeup(dev))
		return -EINVAL;

	handle = DEVICE_ACPI_HANDLE(dev);
	if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
		dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
		return -ENODEV;
	}

	error = enable ?
		acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
		acpi_disable_wakeup_device_power(adev);
	if (!error)
		dev_info(dev, "wake-up capability %s by ACPI\n",
				enable ? "enabled" : "disabled");

	return error;
}
#endif  /* CONFIG_PM_SLEEP */

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

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);
}

/*
 * ACPI 2.0 created the optional _GTS and _BFS,
 * but industry adoption has been neither rapid nor broad.
 *
 * Linux gets into trouble when it executes poorly validated
 * paths through the BIOS, so disable _GTS and _BFS by default,
 * but do speak up and offer the option to enable them.
 */
static void __init acpi_gts_bfs_check(void)
{
	acpi_handle dummy;

	if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
	{
		printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
		printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
			"please notify linux-acpi@vger.kernel.org\n");
	}
	if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
	{
		printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
		printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
			"please notify linux-acpi@vger.kernel.org\n");
	}
}

int __init acpi_sleep_init(void)
{
	acpi_status status;
	u8 type_a, type_b;
#ifdef CONFIG_SUSPEND
	int i = 0;

	dmi_check_system(acpisleep_dmi_table);
#endif

	if (acpi_disabled)
		return 0;

	sleep_states[ACPI_STATE_S0] = 1;
	printk(KERN_INFO PREFIX "(supports S0");

#ifdef CONFIG_SUSPEND
	for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
		status = acpi_get_sleep_type_data(i, &type_a, &type_b);
		if (ACPI_SUCCESS(status)) {
			sleep_states[i] = 1;
			printk(" S%d", i);
		}
	}

	suspend_set_ops(old_suspend_ordering ?
		&acpi_suspend_ops_old : &acpi_suspend_ops);
#endif

#ifdef CONFIG_HIBERNATION
	status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
	if (ACPI_SUCCESS(status)) {
		hibernation_set_ops(old_suspend_ordering ?
			&acpi_hibernation_ops_old : &acpi_hibernation_ops);
		sleep_states[ACPI_STATE_S4] = 1;
		printk(" S4");
		if (!nosigcheck) {
			acpi_get_table(ACPI_SIG_FACS, 1,
				(struct acpi_table_header **)&facs);
			if (facs)
				s4_hardware_signature =
					facs->hardware_signature;
		}
	}
#endif
	status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
	if (ACPI_SUCCESS(status)) {
		sleep_states[ACPI_STATE_S5] = 1;
		printk(" S5");
		pm_power_off_prepare = acpi_power_off_prepare;
		pm_power_off = acpi_power_off;
	}
	printk(")\n");
	/*
	 * 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);
	acpi_gts_bfs_check();
	return 0;
}
OpenPOWER on IntegriCloud