summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/hardware/hwsleep.c
blob: 4290e0193097d28fd2405b814ac0352a0cf5fb93 (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
/******************************************************************************
 *
 * Name: hwsleep.c - ACPI Hardware Sleep/Wake Interface
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2007, R. Byron Moore
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include <acpi/actables.h>

#define _COMPONENT          ACPI_HARDWARE
ACPI_MODULE_NAME("hwsleep")

/*******************************************************************************
 *
 * FUNCTION:    acpi_set_firmware_waking_vector
 *
 * PARAMETERS:  physical_address    - Physical address of ACPI real mode
 *                                    entry point.
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Access function for the firmware_waking_vector field in FACS
 *
 ******************************************************************************/
acpi_status
acpi_set_firmware_waking_vector(acpi_physical_address physical_address)
{
	struct acpi_table_facs *facs;
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector);

	/* Get the FACS */

	status =
	    acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
				    (struct acpi_table_header **)&facs);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Set the vector */

	if ((facs->length < 32) || (!(facs->xfirmware_waking_vector))) {
		/*
		 * ACPI 1.0 FACS or short table or optional X_ field is zero
		 */
		facs->firmware_waking_vector = (u32) physical_address;
	} else {
		/*
		 * ACPI 2.0 FACS with valid X_ field
		 */
		facs->xfirmware_waking_vector = physical_address;
	}

	return_ACPI_STATUS(AE_OK);
}

ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector)

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_firmware_waking_vector
 *
 * PARAMETERS:  *physical_address   - Where the contents of
 *                                    the firmware_waking_vector field of
 *                                    the FACS will be returned.
 *
 * RETURN:      Status, vector
 *
 * DESCRIPTION: Access function for the firmware_waking_vector field in FACS
 *
 ******************************************************************************/
#ifdef ACPI_FUTURE_USAGE
acpi_status
acpi_get_firmware_waking_vector(acpi_physical_address * physical_address)
{
	struct acpi_table_facs *facs;
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_get_firmware_waking_vector);

	if (!physical_address) {
		return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	/* Get the FACS */

	status =
	    acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
				    (struct acpi_table_header **)&facs);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Get the vector */

	if ((facs->length < 32) || (!(facs->xfirmware_waking_vector))) {
		/*
		 * ACPI 1.0 FACS or short table or optional X_ field is zero
		 */
		*physical_address =
		    (acpi_physical_address) facs->firmware_waking_vector;
	} else {
		/*
		 * ACPI 2.0 FACS with valid X_ field
		 */
		*physical_address =
		    (acpi_physical_address) facs->xfirmware_waking_vector;
	}

	return_ACPI_STATUS(AE_OK);
}

ACPI_EXPORT_SYMBOL(acpi_get_firmware_waking_vector)
#endif
/*******************************************************************************
 *
 * FUNCTION:    acpi_enter_sleep_state_prep
 *
 * PARAMETERS:  sleep_state         - Which sleep state to enter
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Prepare to enter a system sleep state (see ACPI 2.0 spec p 231)
 *              This function must execute with interrupts enabled.
 *              We break sleeping into 2 stages so that OSPM can handle
 *              various OS-specific tasks between the two steps.
 *
 ******************************************************************************/
acpi_status acpi_enter_sleep_state_prep(u8 sleep_state)
{
	acpi_status status;
	struct acpi_object_list arg_list;
	union acpi_object arg;

	ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_prep);

	/*
	 * _PSW methods could be run here to enable wake-on keyboard, LAN, etc.
	 */
	status = acpi_get_sleep_type_data(sleep_state,
					  &acpi_gbl_sleep_type_a,
					  &acpi_gbl_sleep_type_b);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Setup parameter object */

	arg_list.count = 1;
	arg_list.pointer = &arg;

	arg.type = ACPI_TYPE_INTEGER;
	arg.integer.value = sleep_state;

	/* Run the _PTS method */

	status = acpi_evaluate_object(NULL, METHOD_NAME__PTS, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		return_ACPI_STATUS(status);
	}

	/* Setup the argument to _SST */

	switch (sleep_state) {
	case ACPI_STATE_S0:
		arg.integer.value = ACPI_SST_WORKING;
		break;

	case ACPI_STATE_S1:
	case ACPI_STATE_S2:
	case ACPI_STATE_S3:
		arg.integer.value = ACPI_SST_SLEEPING;
		break;

	case ACPI_STATE_S4:
		arg.integer.value = ACPI_SST_SLEEP_CONTEXT;
		break;

	default:
		arg.integer.value = ACPI_SST_INDICATOR_OFF;	/* Default is off */
		break;
	}

	/* Set the system indicators to show the desired sleep state. */

	status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		ACPI_EXCEPTION((AE_INFO, status,
				"While executing method _SST"));
	}

	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_prep)

/*******************************************************************************
 *
 * FUNCTION:    acpi_enter_sleep_state
 *
 * PARAMETERS:  sleep_state         - Which sleep state to enter
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Enter a system sleep state (see ACPI 2.0 spec p 231)
 *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 *
 ******************************************************************************/
acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
{
	u32 PM1Acontrol;
	u32 PM1Bcontrol;
	struct acpi_bit_register_info *sleep_type_reg_info;
	struct acpi_bit_register_info *sleep_enable_reg_info;
	u32 in_value;
	struct acpi_object_list arg_list;
	union acpi_object arg;
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_enter_sleep_state);

	if ((acpi_gbl_sleep_type_a > ACPI_SLEEP_TYPE_MAX) ||
	    (acpi_gbl_sleep_type_b > ACPI_SLEEP_TYPE_MAX)) {
		ACPI_ERROR((AE_INFO, "Sleep values out of range: A=%X B=%X",
			    acpi_gbl_sleep_type_a, acpi_gbl_sleep_type_b));
		return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
	}

	sleep_type_reg_info =
	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE_A);
	sleep_enable_reg_info =
	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);

	/* Clear wake status */

	status = acpi_set_register(ACPI_BITREG_WAKE_STATUS, 1);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Clear all fixed and general purpose status bits */

	status = acpi_hw_clear_acpi_status();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/*
	 * 1) Disable/Clear all GPEs
	 * 2) Enable all wakeup GPEs
	 */
	status = acpi_hw_disable_all_gpes();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}
	acpi_gbl_system_awake_and_running = FALSE;

	status = acpi_hw_enable_all_wakeup_gpes();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Execute the _GTS method */

	arg_list.count = 1;
	arg_list.pointer = &arg;
	arg.type = ACPI_TYPE_INTEGER;
	arg.integer.value = sleep_state;

	status = acpi_evaluate_object(NULL, METHOD_NAME__GTS, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		return_ACPI_STATUS(status);
	}

	/* Get current value of PM1A control */

	status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL, &PM1Acontrol);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}
	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
			  "Entering sleep state [S%d]\n", sleep_state));

	/* Clear SLP_EN and SLP_TYP fields */

	PM1Acontrol &= ~(sleep_type_reg_info->access_bit_mask |
			 sleep_enable_reg_info->access_bit_mask);
	PM1Bcontrol = PM1Acontrol;

	/* Insert SLP_TYP bits */

	PM1Acontrol |=
	    (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
	PM1Bcontrol |=
	    (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);

	/*
	 * We split the writes of SLP_TYP and SLP_EN to workaround
	 * poorly implemented hardware.
	 */

	/* Write #1: fill in SLP_TYP data */

	status = acpi_hw_register_write(ACPI_REGISTER_PM1A_CONTROL,
					PM1Acontrol);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	status = acpi_hw_register_write(ACPI_REGISTER_PM1B_CONTROL,
					PM1Bcontrol);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Insert SLP_ENABLE bit */

	PM1Acontrol |= sleep_enable_reg_info->access_bit_mask;
	PM1Bcontrol |= sleep_enable_reg_info->access_bit_mask;

	/* Write #2: SLP_TYP + SLP_EN */

	ACPI_FLUSH_CPU_CACHE();

	status = acpi_hw_register_write(ACPI_REGISTER_PM1A_CONTROL,
					PM1Acontrol);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	status = acpi_hw_register_write(ACPI_REGISTER_PM1B_CONTROL,
					PM1Bcontrol);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	if (sleep_state > ACPI_STATE_S3) {
		/*
		 * We wanted to sleep > S3, but it didn't happen (by virtue of the
		 * fact that we are still executing!)
		 *
		 * Wait ten seconds, then try again. This is to get S4/S5 to work on
		 * all machines.
		 *
		 * We wait so long to allow chipsets that poll this reg very slowly to
		 * still read the right value. Ideally, this block would go
		 * away entirely.
		 */
		acpi_os_stall(10000000);

		status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
						sleep_enable_reg_info->
						access_bit_mask);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}
	}

	/* Wait until we enter sleep state */

	do {
		status = acpi_get_register_unlocked(ACPI_BITREG_WAKE_STATUS,
						    &in_value);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}

		/* Spin until we wake */

	} while (!in_value);

	return_ACPI_STATUS(AE_OK);
}

ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state)

/*******************************************************************************
 *
 * FUNCTION:    acpi_enter_sleep_state_s4bios
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform a S4 bios request.
 *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 *
 ******************************************************************************/
acpi_status asmlinkage acpi_enter_sleep_state_s4bios(void)
{
	u32 in_value;
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_s4bios);

	status = acpi_set_register(ACPI_BITREG_WAKE_STATUS, 1);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	status = acpi_hw_clear_acpi_status();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/*
	 * 1) Disable/Clear all GPEs
	 * 2) Enable all wakeup GPEs
	 */
	status = acpi_hw_disable_all_gpes();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}
	acpi_gbl_system_awake_and_running = FALSE;

	status = acpi_hw_enable_all_wakeup_gpes();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	ACPI_FLUSH_CPU_CACHE();

	status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
				    (u32) acpi_gbl_FADT.S4bios_request, 8);

	do {
		acpi_os_stall(1000);
		status = acpi_get_register(ACPI_BITREG_WAKE_STATUS, &in_value);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}
	} while (!in_value);

	return_ACPI_STATUS(AE_OK);
}

ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_s4bios)

/*******************************************************************************
 *
 * FUNCTION:    acpi_leave_sleep_state_prep
 *
 * PARAMETERS:  sleep_state         - Which sleep state we are exiting
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
 *              sleep.
 *              Called with interrupts DISABLED.
 *
 ******************************************************************************/
acpi_status acpi_leave_sleep_state_prep(u8 sleep_state)
{
	struct acpi_object_list arg_list;
	union acpi_object arg;
	acpi_status status;
	struct acpi_bit_register_info *sleep_type_reg_info;
	struct acpi_bit_register_info *sleep_enable_reg_info;
	u32 PM1Acontrol;
	u32 PM1Bcontrol;

	ACPI_FUNCTION_TRACE(acpi_leave_sleep_state_prep);

	/*
	 * Set SLP_TYPE and SLP_EN to state S0.
	 * This is unclear from the ACPI Spec, but it is required
	 * by some machines.
	 */
	status = acpi_get_sleep_type_data(ACPI_STATE_S0,
					  &acpi_gbl_sleep_type_a,
					  &acpi_gbl_sleep_type_b);
	if (ACPI_SUCCESS(status)) {
		sleep_type_reg_info =
		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE_A);
		sleep_enable_reg_info =
		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);

		/* Get current value of PM1A control */

		status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
					       &PM1Acontrol);
		if (ACPI_SUCCESS(status)) {

			/* Clear SLP_EN and SLP_TYP fields */

			PM1Acontrol &= ~(sleep_type_reg_info->access_bit_mask |
					 sleep_enable_reg_info->
					 access_bit_mask);
			PM1Bcontrol = PM1Acontrol;

			/* Insert SLP_TYP bits */

			PM1Acontrol |=
			    (acpi_gbl_sleep_type_a << sleep_type_reg_info->
			     bit_position);
			PM1Bcontrol |=
			    (acpi_gbl_sleep_type_b << sleep_type_reg_info->
			     bit_position);

			/* Just ignore any errors */

			(void)acpi_hw_register_write(ACPI_REGISTER_PM1A_CONTROL,
						     PM1Acontrol);
			(void)acpi_hw_register_write(ACPI_REGISTER_PM1B_CONTROL,
						     PM1Bcontrol);
		}
	}

	/* Execute the _BFS method */

	arg_list.count = 1;
	arg_list.pointer = &arg;
	arg.type = ACPI_TYPE_INTEGER;
	arg.integer.value = sleep_state;

	status = acpi_evaluate_object(NULL, METHOD_NAME__BFS, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		ACPI_EXCEPTION((AE_INFO, status, "During Method _BFS"));
	}

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_leave_sleep_state
 *
 * PARAMETERS:  sleep_state         - Which sleep state we just exited
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 *              Called with interrupts ENABLED.
 *
 ******************************************************************************/
acpi_status acpi_leave_sleep_state(u8 sleep_state)
{
	struct acpi_object_list arg_list;
	union acpi_object arg;
	acpi_status status;

	ACPI_FUNCTION_TRACE(acpi_leave_sleep_state);

	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */

	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;

	/* Setup parameter object */

	arg_list.count = 1;
	arg_list.pointer = &arg;
	arg.type = ACPI_TYPE_INTEGER;

	/* Ignore any errors from these methods */

	arg.integer.value = ACPI_SST_WAKING;
	status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
	}

	/*
	 * GPEs must be enabled before _WAK is called as GPEs
	 * might get fired there
	 *
	 * Restore the GPEs:
	 * 1) Disable/Clear all GPEs
	 * 2) Enable all runtime GPEs
	 */
	status = acpi_hw_disable_all_gpes();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}
	status = acpi_hw_enable_all_runtime_gpes();
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	arg.integer.value = sleep_state;
	status = acpi_evaluate_object(NULL, METHOD_NAME__WAK, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		ACPI_EXCEPTION((AE_INFO, status, "During Method _WAK"));
	}
	/* TBD: _WAK "sometimes" returns stuff - do we want to look at it? */

	acpi_gbl_system_awake_and_running = TRUE;

	/* Enable power button */

	(void)
	    acpi_set_register(acpi_gbl_fixed_event_info
			      [ACPI_EVENT_POWER_BUTTON].enable_register_id, 1);

	(void)
	    acpi_set_register(acpi_gbl_fixed_event_info
			      [ACPI_EVENT_POWER_BUTTON].status_register_id, 1);

	arg.integer.value = ACPI_SST_WORKING;
	status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
	}

	return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_leave_sleep_state)