xref: /openbmc/linux/drivers/acpi/acpica/hwsleep.c (revision b8bb76713ec50df2f11efee386e16f93d51e1076)
1 
2 /******************************************************************************
3  *
4  * Name: hwsleep.c - ACPI Hardware Sleep/Wake Interface
5  *
6  *****************************************************************************/
7 
8 /*
9  * Copyright (C) 2000 - 2008, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44 
45 #include <acpi/acpi.h>
46 #include "accommon.h"
47 #include "actables.h"
48 
49 #define _COMPONENT          ACPI_HARDWARE
50 ACPI_MODULE_NAME("hwsleep")
51 
52 /*******************************************************************************
53  *
54  * FUNCTION:    acpi_set_firmware_waking_vector
55  *
56  * PARAMETERS:  physical_address    - 32-bit physical address of ACPI real mode
57  *                                    entry point.
58  *
59  * RETURN:      Status
60  *
61  * DESCRIPTION: Sets the 32-bit firmware_waking_vector field of the FACS
62  *
63  ******************************************************************************/
64 acpi_status
65 acpi_set_firmware_waking_vector(u32 physical_address)
66 {
67 	ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector);
68 
69 
70 	/*
71 	 * According to the ACPI specification 2.0c and later, the 64-bit
72 	 * waking vector should be cleared and the 32-bit waking vector should
73 	 * be used, unless we want the wake-up code to be called by the BIOS in
74 	 * Protected Mode.  Some systems (for example HP dv5-1004nr) are known
75 	 * to fail to resume if the 64-bit vector is used.
76 	 */
77 
78 	/* Set the 32-bit vector */
79 
80 	acpi_gbl_FACS->firmware_waking_vector = physical_address;
81 
82 	/* Clear the 64-bit vector if it exists */
83 
84 	if ((acpi_gbl_FACS->length > 32) && (acpi_gbl_FACS->version >= 1)) {
85 		acpi_gbl_FACS->xfirmware_waking_vector = 0;
86 	}
87 
88 	return_ACPI_STATUS(AE_OK);
89 }
90 
91 ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector)
92 
93 /*******************************************************************************
94  *
95  * FUNCTION:    acpi_set_firmware_waking_vector64
96  *
97  * PARAMETERS:  physical_address    - 64-bit physical address of ACPI protected
98  *                                    mode entry point.
99  *
100  * RETURN:      Status
101  *
102  * DESCRIPTION: Sets the 64-bit X_firmware_waking_vector field of the FACS, if
103  *              it exists in the table.
104  *
105  ******************************************************************************/
106 acpi_status
107 acpi_set_firmware_waking_vector64(u64 physical_address)
108 {
109 	ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector64);
110 
111 
112 	/* Determine if the 64-bit vector actually exists */
113 
114 	if ((acpi_gbl_FACS->length <= 32) || (acpi_gbl_FACS->version < 1)) {
115 		return_ACPI_STATUS(AE_NOT_EXIST);
116 	}
117 
118 	/* Clear 32-bit vector, set the 64-bit X_ vector */
119 
120 	acpi_gbl_FACS->firmware_waking_vector = 0;
121 	acpi_gbl_FACS->xfirmware_waking_vector = physical_address;
122 
123 	return_ACPI_STATUS(AE_OK);
124 }
125 
126 ACPI_EXPORT_SYMBOL(acpi_set_firmware_waking_vector64)
127 
128 /*******************************************************************************
129  *
130  * FUNCTION:    acpi_enter_sleep_state_prep
131  *
132  * PARAMETERS:  sleep_state         - Which sleep state to enter
133  *
134  * RETURN:      Status
135  *
136  * DESCRIPTION: Prepare to enter a system sleep state (see ACPI 2.0 spec p 231)
137  *              This function must execute with interrupts enabled.
138  *              We break sleeping into 2 stages so that OSPM can handle
139  *              various OS-specific tasks between the two steps.
140  *
141  ******************************************************************************/
142 acpi_status acpi_enter_sleep_state_prep(u8 sleep_state)
143 {
144 	acpi_status status;
145 	struct acpi_object_list arg_list;
146 	union acpi_object arg;
147 
148 	ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_prep);
149 
150 	/*
151 	 * _PSW methods could be run here to enable wake-on keyboard, LAN, etc.
152 	 */
153 	status = acpi_get_sleep_type_data(sleep_state,
154 					  &acpi_gbl_sleep_type_a,
155 					  &acpi_gbl_sleep_type_b);
156 	if (ACPI_FAILURE(status)) {
157 		return_ACPI_STATUS(status);
158 	}
159 
160 	/* Setup parameter object */
161 
162 	arg_list.count = 1;
163 	arg_list.pointer = &arg;
164 
165 	arg.type = ACPI_TYPE_INTEGER;
166 	arg.integer.value = sleep_state;
167 
168 	/* Run the _PTS method */
169 
170 	status = acpi_evaluate_object(NULL, METHOD_NAME__PTS, &arg_list, NULL);
171 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
172 		return_ACPI_STATUS(status);
173 	}
174 
175 	/* Setup the argument to _SST */
176 
177 	switch (sleep_state) {
178 	case ACPI_STATE_S0:
179 		arg.integer.value = ACPI_SST_WORKING;
180 		break;
181 
182 	case ACPI_STATE_S1:
183 	case ACPI_STATE_S2:
184 	case ACPI_STATE_S3:
185 		arg.integer.value = ACPI_SST_SLEEPING;
186 		break;
187 
188 	case ACPI_STATE_S4:
189 		arg.integer.value = ACPI_SST_SLEEP_CONTEXT;
190 		break;
191 
192 	default:
193 		arg.integer.value = ACPI_SST_INDICATOR_OFF;	/* Default is off */
194 		break;
195 	}
196 
197 	/*
198 	 * Set the system indicators to show the desired sleep state.
199 	 * _SST is an optional method (return no error if not found)
200 	 */
201 	status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
202 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
203 		ACPI_EXCEPTION((AE_INFO, status,
204 				"While executing method _SST"));
205 	}
206 
207 	return_ACPI_STATUS(AE_OK);
208 }
209 
210 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_prep)
211 
212 /*******************************************************************************
213  *
214  * FUNCTION:    acpi_enter_sleep_state
215  *
216  * PARAMETERS:  sleep_state         - Which sleep state to enter
217  *
218  * RETURN:      Status
219  *
220  * DESCRIPTION: Enter a system sleep state (see ACPI 2.0 spec p 231)
221  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
222  *
223  ******************************************************************************/
224 acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
225 {
226 	u32 PM1Acontrol;
227 	u32 PM1Bcontrol;
228 	struct acpi_bit_register_info *sleep_type_reg_info;
229 	struct acpi_bit_register_info *sleep_enable_reg_info;
230 	u32 in_value;
231 	struct acpi_object_list arg_list;
232 	union acpi_object arg;
233 	acpi_status status;
234 
235 	ACPI_FUNCTION_TRACE(acpi_enter_sleep_state);
236 
237 	if ((acpi_gbl_sleep_type_a > ACPI_SLEEP_TYPE_MAX) ||
238 	    (acpi_gbl_sleep_type_b > ACPI_SLEEP_TYPE_MAX)) {
239 		ACPI_ERROR((AE_INFO, "Sleep values out of range: A=%X B=%X",
240 			    acpi_gbl_sleep_type_a, acpi_gbl_sleep_type_b));
241 		return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
242 	}
243 
244 	sleep_type_reg_info =
245 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE_A);
246 	sleep_enable_reg_info =
247 	    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
248 
249 	/* Clear wake status */
250 
251 	status = acpi_set_register(ACPI_BITREG_WAKE_STATUS, 1);
252 	if (ACPI_FAILURE(status)) {
253 		return_ACPI_STATUS(status);
254 	}
255 
256 	/* Clear all fixed and general purpose status bits */
257 
258 	status = acpi_hw_clear_acpi_status();
259 	if (ACPI_FAILURE(status)) {
260 		return_ACPI_STATUS(status);
261 	}
262 
263 	/*
264 	 * 1) Disable/Clear all GPEs
265 	 * 2) Enable all wakeup GPEs
266 	 */
267 	status = acpi_hw_disable_all_gpes();
268 	if (ACPI_FAILURE(status)) {
269 		return_ACPI_STATUS(status);
270 	}
271 	acpi_gbl_system_awake_and_running = FALSE;
272 
273 	status = acpi_hw_enable_all_wakeup_gpes();
274 	if (ACPI_FAILURE(status)) {
275 		return_ACPI_STATUS(status);
276 	}
277 
278 	/* Execute the _GTS method */
279 
280 	arg_list.count = 1;
281 	arg_list.pointer = &arg;
282 	arg.type = ACPI_TYPE_INTEGER;
283 	arg.integer.value = sleep_state;
284 
285 	status = acpi_evaluate_object(NULL, METHOD_NAME__GTS, &arg_list, NULL);
286 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
287 		return_ACPI_STATUS(status);
288 	}
289 
290 	/* Get current value of PM1A control */
291 
292 	status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL, &PM1Acontrol);
293 	if (ACPI_FAILURE(status)) {
294 		return_ACPI_STATUS(status);
295 	}
296 	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
297 			  "Entering sleep state [S%d]\n", sleep_state));
298 
299 	/* Clear SLP_EN and SLP_TYP fields */
300 
301 	PM1Acontrol &= ~(sleep_type_reg_info->access_bit_mask |
302 			 sleep_enable_reg_info->access_bit_mask);
303 	PM1Bcontrol = PM1Acontrol;
304 
305 	/* Insert SLP_TYP bits */
306 
307 	PM1Acontrol |=
308 	    (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
309 	PM1Bcontrol |=
310 	    (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
311 
312 	/*
313 	 * We split the writes of SLP_TYP and SLP_EN to workaround
314 	 * poorly implemented hardware.
315 	 */
316 
317 	/* Write #1: fill in SLP_TYP data */
318 
319 	status = acpi_hw_register_write(ACPI_REGISTER_PM1A_CONTROL,
320 					PM1Acontrol);
321 	if (ACPI_FAILURE(status)) {
322 		return_ACPI_STATUS(status);
323 	}
324 
325 	status = acpi_hw_register_write(ACPI_REGISTER_PM1B_CONTROL,
326 					PM1Bcontrol);
327 	if (ACPI_FAILURE(status)) {
328 		return_ACPI_STATUS(status);
329 	}
330 
331 	/* Insert SLP_ENABLE bit */
332 
333 	PM1Acontrol |= sleep_enable_reg_info->access_bit_mask;
334 	PM1Bcontrol |= sleep_enable_reg_info->access_bit_mask;
335 
336 	/* Write #2: SLP_TYP + SLP_EN */
337 
338 	ACPI_FLUSH_CPU_CACHE();
339 
340 	status = acpi_hw_register_write(ACPI_REGISTER_PM1A_CONTROL,
341 					PM1Acontrol);
342 	if (ACPI_FAILURE(status)) {
343 		return_ACPI_STATUS(status);
344 	}
345 
346 	status = acpi_hw_register_write(ACPI_REGISTER_PM1B_CONTROL,
347 					PM1Bcontrol);
348 	if (ACPI_FAILURE(status)) {
349 		return_ACPI_STATUS(status);
350 	}
351 
352 	if (sleep_state > ACPI_STATE_S3) {
353 		/*
354 		 * We wanted to sleep > S3, but it didn't happen (by virtue of the
355 		 * fact that we are still executing!)
356 		 *
357 		 * Wait ten seconds, then try again. This is to get S4/S5 to work on
358 		 * all machines.
359 		 *
360 		 * We wait so long to allow chipsets that poll this reg very slowly to
361 		 * still read the right value. Ideally, this block would go
362 		 * away entirely.
363 		 */
364 		acpi_os_stall(10000000);
365 
366 		status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
367 						sleep_enable_reg_info->
368 						access_bit_mask);
369 		if (ACPI_FAILURE(status)) {
370 			return_ACPI_STATUS(status);
371 		}
372 	}
373 
374 	/* Wait until we enter sleep state */
375 
376 	do {
377 		status = acpi_get_register_unlocked(ACPI_BITREG_WAKE_STATUS,
378 						    &in_value);
379 		if (ACPI_FAILURE(status)) {
380 			return_ACPI_STATUS(status);
381 		}
382 
383 		/* Spin until we wake */
384 
385 	} while (!in_value);
386 
387 	return_ACPI_STATUS(AE_OK);
388 }
389 
390 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state)
391 
392 /*******************************************************************************
393  *
394  * FUNCTION:    acpi_enter_sleep_state_s4bios
395  *
396  * PARAMETERS:  None
397  *
398  * RETURN:      Status
399  *
400  * DESCRIPTION: Perform a S4 bios request.
401  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
402  *
403  ******************************************************************************/
404 acpi_status asmlinkage acpi_enter_sleep_state_s4bios(void)
405 {
406 	u32 in_value;
407 	acpi_status status;
408 
409 	ACPI_FUNCTION_TRACE(acpi_enter_sleep_state_s4bios);
410 
411 	status = acpi_set_register(ACPI_BITREG_WAKE_STATUS, 1);
412 	if (ACPI_FAILURE(status)) {
413 		return_ACPI_STATUS(status);
414 	}
415 
416 	status = acpi_hw_clear_acpi_status();
417 	if (ACPI_FAILURE(status)) {
418 		return_ACPI_STATUS(status);
419 	}
420 
421 	/*
422 	 * 1) Disable/Clear all GPEs
423 	 * 2) Enable all wakeup GPEs
424 	 */
425 	status = acpi_hw_disable_all_gpes();
426 	if (ACPI_FAILURE(status)) {
427 		return_ACPI_STATUS(status);
428 	}
429 	acpi_gbl_system_awake_and_running = FALSE;
430 
431 	status = acpi_hw_enable_all_wakeup_gpes();
432 	if (ACPI_FAILURE(status)) {
433 		return_ACPI_STATUS(status);
434 	}
435 
436 	ACPI_FLUSH_CPU_CACHE();
437 
438 	status = acpi_os_write_port(acpi_gbl_FADT.smi_command,
439 				    (u32) acpi_gbl_FADT.S4bios_request, 8);
440 
441 	do {
442 		acpi_os_stall(1000);
443 		status = acpi_get_register(ACPI_BITREG_WAKE_STATUS, &in_value);
444 		if (ACPI_FAILURE(status)) {
445 			return_ACPI_STATUS(status);
446 		}
447 	} while (!in_value);
448 
449 	return_ACPI_STATUS(AE_OK);
450 }
451 
452 ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_s4bios)
453 
454 /*******************************************************************************
455  *
456  * FUNCTION:    acpi_leave_sleep_state_prep
457  *
458  * PARAMETERS:  sleep_state         - Which sleep state we are exiting
459  *
460  * RETURN:      Status
461  *
462  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
463  *              sleep.
464  *              Called with interrupts DISABLED.
465  *
466  ******************************************************************************/
467 acpi_status acpi_leave_sleep_state_prep(u8 sleep_state)
468 {
469 	struct acpi_object_list arg_list;
470 	union acpi_object arg;
471 	acpi_status status;
472 	struct acpi_bit_register_info *sleep_type_reg_info;
473 	struct acpi_bit_register_info *sleep_enable_reg_info;
474 	u32 PM1Acontrol;
475 	u32 PM1Bcontrol;
476 
477 	ACPI_FUNCTION_TRACE(acpi_leave_sleep_state_prep);
478 
479 	/*
480 	 * Set SLP_TYPE and SLP_EN to state S0.
481 	 * This is unclear from the ACPI Spec, but it is required
482 	 * by some machines.
483 	 */
484 	status = acpi_get_sleep_type_data(ACPI_STATE_S0,
485 					  &acpi_gbl_sleep_type_a,
486 					  &acpi_gbl_sleep_type_b);
487 	if (ACPI_SUCCESS(status)) {
488 		sleep_type_reg_info =
489 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE_A);
490 		sleep_enable_reg_info =
491 		    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
492 
493 		/* Get current value of PM1A control */
494 
495 		status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
496 					       &PM1Acontrol);
497 		if (ACPI_SUCCESS(status)) {
498 
499 			/* Clear SLP_EN and SLP_TYP fields */
500 
501 			PM1Acontrol &= ~(sleep_type_reg_info->access_bit_mask |
502 					 sleep_enable_reg_info->
503 					 access_bit_mask);
504 			PM1Bcontrol = PM1Acontrol;
505 
506 			/* Insert SLP_TYP bits */
507 
508 			PM1Acontrol |=
509 			    (acpi_gbl_sleep_type_a << sleep_type_reg_info->
510 			     bit_position);
511 			PM1Bcontrol |=
512 			    (acpi_gbl_sleep_type_b << sleep_type_reg_info->
513 			     bit_position);
514 
515 			/* Just ignore any errors */
516 
517 			(void)acpi_hw_register_write(ACPI_REGISTER_PM1A_CONTROL,
518 						     PM1Acontrol);
519 			(void)acpi_hw_register_write(ACPI_REGISTER_PM1B_CONTROL,
520 						     PM1Bcontrol);
521 		}
522 	}
523 
524 	/* Execute the _BFS method */
525 
526 	arg_list.count = 1;
527 	arg_list.pointer = &arg;
528 	arg.type = ACPI_TYPE_INTEGER;
529 	arg.integer.value = sleep_state;
530 
531 	status = acpi_evaluate_object(NULL, METHOD_NAME__BFS, &arg_list, NULL);
532 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
533 		ACPI_EXCEPTION((AE_INFO, status, "During Method _BFS"));
534 	}
535 
536 	return_ACPI_STATUS(status);
537 }
538 
539 /*******************************************************************************
540  *
541  * FUNCTION:    acpi_leave_sleep_state
542  *
543  * PARAMETERS:  sleep_state         - Which sleep state we just exited
544  *
545  * RETURN:      Status
546  *
547  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
548  *              Called with interrupts ENABLED.
549  *
550  ******************************************************************************/
551 acpi_status acpi_leave_sleep_state(u8 sleep_state)
552 {
553 	struct acpi_object_list arg_list;
554 	union acpi_object arg;
555 	acpi_status status;
556 
557 	ACPI_FUNCTION_TRACE(acpi_leave_sleep_state);
558 
559 	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
560 
561 	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
562 
563 	/* Setup parameter object */
564 
565 	arg_list.count = 1;
566 	arg_list.pointer = &arg;
567 	arg.type = ACPI_TYPE_INTEGER;
568 
569 	/* Ignore any errors from these methods */
570 
571 	arg.integer.value = ACPI_SST_WAKING;
572 	status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
573 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
574 		ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
575 	}
576 
577 	/*
578 	 * GPEs must be enabled before _WAK is called as GPEs
579 	 * might get fired there
580 	 *
581 	 * Restore the GPEs:
582 	 * 1) Disable/Clear all GPEs
583 	 * 2) Enable all runtime GPEs
584 	 */
585 	status = acpi_hw_disable_all_gpes();
586 	if (ACPI_FAILURE(status)) {
587 		return_ACPI_STATUS(status);
588 	}
589 	status = acpi_hw_enable_all_runtime_gpes();
590 	if (ACPI_FAILURE(status)) {
591 		return_ACPI_STATUS(status);
592 	}
593 
594 	arg.integer.value = sleep_state;
595 	status = acpi_evaluate_object(NULL, METHOD_NAME__WAK, &arg_list, NULL);
596 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
597 		ACPI_EXCEPTION((AE_INFO, status, "During Method _WAK"));
598 	}
599 	/* TBD: _WAK "sometimes" returns stuff - do we want to look at it? */
600 
601 	/*
602 	 * Some BIOSes assume that WAK_STS will be cleared on resume and use
603 	 * it to determine whether the system is rebooting or resuming. Clear
604 	 * it for compatibility.
605 	 */
606 	acpi_set_register(ACPI_BITREG_WAKE_STATUS, 1);
607 
608 	acpi_gbl_system_awake_and_running = TRUE;
609 
610 	/* Enable power button */
611 
612 	(void)
613 	    acpi_set_register(acpi_gbl_fixed_event_info
614 			      [ACPI_EVENT_POWER_BUTTON].enable_register_id, 1);
615 
616 	(void)
617 	    acpi_set_register(acpi_gbl_fixed_event_info
618 			      [ACPI_EVENT_POWER_BUTTON].status_register_id, 1);
619 
620 	arg.integer.value = ACPI_SST_WORKING;
621 	status = acpi_evaluate_object(NULL, METHOD_NAME__SST, &arg_list, NULL);
622 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
623 		ACPI_EXCEPTION((AE_INFO, status, "During Method _SST"));
624 	}
625 
626 	return_ACPI_STATUS(status);
627 }
628 
629 ACPI_EXPORT_SYMBOL(acpi_leave_sleep_state)
630