xref: /linux/drivers/acpi/sleep.c (revision cc4589ebfae6f8dbb5cf880a0a67eedab3416492)
1 /*
2  * sleep.c - ACPI sleep support.
3  *
4  * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
5  * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
6  * Copyright (c) 2000-2003 Patrick Mochel
7  * Copyright (c) 2003 Open Source Development Lab
8  *
9  * This file is released under the GPLv2.
10  *
11  */
12 
13 #include <linux/delay.h>
14 #include <linux/irq.h>
15 #include <linux/dmi.h>
16 #include <linux/device.h>
17 #include <linux/suspend.h>
18 #include <linux/reboot.h>
19 
20 #include <asm/io.h>
21 
22 #include <acpi/acpi_bus.h>
23 #include <acpi/acpi_drivers.h>
24 
25 #include "internal.h"
26 #include "sleep.h"
27 
28 u8 sleep_states[ACPI_S_STATE_COUNT];
29 
30 static void acpi_sleep_tts_switch(u32 acpi_state)
31 {
32 	union acpi_object in_arg = { ACPI_TYPE_INTEGER };
33 	struct acpi_object_list arg_list = { 1, &in_arg };
34 	acpi_status status = AE_OK;
35 
36 	in_arg.integer.value = acpi_state;
37 	status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
38 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
39 		/*
40 		 * OS can't evaluate the _TTS object correctly. Some warning
41 		 * message will be printed. But it won't break anything.
42 		 */
43 		printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
44 	}
45 }
46 
47 static int tts_notify_reboot(struct notifier_block *this,
48 			unsigned long code, void *x)
49 {
50 	acpi_sleep_tts_switch(ACPI_STATE_S5);
51 	return NOTIFY_DONE;
52 }
53 
54 static struct notifier_block tts_notifier = {
55 	.notifier_call	= tts_notify_reboot,
56 	.next		= NULL,
57 	.priority	= 0,
58 };
59 
60 static int acpi_sleep_prepare(u32 acpi_state)
61 {
62 #ifdef CONFIG_ACPI_SLEEP
63 	/* do we have a wakeup address for S2 and S3? */
64 	if (acpi_state == ACPI_STATE_S3) {
65 		if (!acpi_wakeup_address) {
66 			return -EFAULT;
67 		}
68 		acpi_set_firmware_waking_vector(
69 				(acpi_physical_address)acpi_wakeup_address);
70 
71 	}
72 	ACPI_FLUSH_CPU_CACHE();
73 	acpi_enable_wakeup_device_prep(acpi_state);
74 #endif
75 	printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
76 		acpi_state);
77 	acpi_enter_sleep_state_prep(acpi_state);
78 	return 0;
79 }
80 
81 #ifdef CONFIG_ACPI_SLEEP
82 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
83 
84 /*
85  * The ACPI specification wants us to save NVS memory regions during hibernation
86  * and to restore them during the subsequent resume.  Windows does that also for
87  * suspend to RAM.  However, it is known that this mechanism does not work on
88  * all machines, so we allow the user to disable it with the help of the
89  * 'acpi_sleep=nonvs' kernel command line option.
90  */
91 static bool nvs_nosave;
92 
93 void __init acpi_nvs_nosave(void)
94 {
95 	nvs_nosave = true;
96 }
97 
98 /*
99  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
100  * user to request that behavior by using the 'acpi_old_suspend_ordering'
101  * kernel command line option that causes the following variable to be set.
102  */
103 static bool old_suspend_ordering;
104 
105 void __init acpi_old_suspend_ordering(void)
106 {
107 	old_suspend_ordering = true;
108 }
109 
110 /**
111  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
112  */
113 static int acpi_pm_freeze(void)
114 {
115 	acpi_disable_all_gpes();
116 	acpi_os_wait_events_complete(NULL);
117 	acpi_ec_block_transactions();
118 	return 0;
119 }
120 
121 /**
122  *	__acpi_pm_prepare - Prepare the platform to enter the target state.
123  *
124  *	If necessary, set the firmware waking vector and do arch-specific
125  *	nastiness to get the wakeup code to the waking vector.
126  */
127 static int __acpi_pm_prepare(void)
128 {
129 	int error = acpi_sleep_prepare(acpi_target_sleep_state);
130 
131 	suspend_nvs_save();
132 
133 	if (error)
134 		acpi_target_sleep_state = ACPI_STATE_S0;
135 	return error;
136 }
137 
138 /**
139  *	acpi_pm_prepare - Prepare the platform to enter the target sleep
140  *		state and disable the GPEs.
141  */
142 static int acpi_pm_prepare(void)
143 {
144 	int error = __acpi_pm_prepare();
145 
146 	if (!error)
147 		acpi_pm_freeze();
148 
149 	return error;
150 }
151 
152 /**
153  *	acpi_pm_finish - Instruct the platform to leave a sleep state.
154  *
155  *	This is called after we wake back up (or if entering the sleep state
156  *	failed).
157  */
158 static void acpi_pm_finish(void)
159 {
160 	u32 acpi_state = acpi_target_sleep_state;
161 
162 	suspend_nvs_free();
163 	acpi_ec_unblock_transactions();
164 
165 	if (acpi_state == ACPI_STATE_S0)
166 		return;
167 
168 	printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
169 		acpi_state);
170 	acpi_disable_wakeup_device(acpi_state);
171 	acpi_leave_sleep_state(acpi_state);
172 
173 	/* reset firmware waking vector */
174 	acpi_set_firmware_waking_vector((acpi_physical_address) 0);
175 
176 	acpi_target_sleep_state = ACPI_STATE_S0;
177 }
178 
179 /**
180  *	acpi_pm_end - Finish up suspend sequence.
181  */
182 static void acpi_pm_end(void)
183 {
184 	/*
185 	 * This is necessary in case acpi_pm_finish() is not called during a
186 	 * failing transition to a sleep state.
187 	 */
188 	acpi_target_sleep_state = ACPI_STATE_S0;
189 	acpi_sleep_tts_switch(acpi_target_sleep_state);
190 }
191 #else /* !CONFIG_ACPI_SLEEP */
192 #define acpi_target_sleep_state	ACPI_STATE_S0
193 #endif /* CONFIG_ACPI_SLEEP */
194 
195 #ifdef CONFIG_SUSPEND
196 extern void do_suspend_lowlevel(void);
197 
198 static u32 acpi_suspend_states[] = {
199 	[PM_SUSPEND_ON] = ACPI_STATE_S0,
200 	[PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
201 	[PM_SUSPEND_MEM] = ACPI_STATE_S3,
202 	[PM_SUSPEND_MAX] = ACPI_STATE_S5
203 };
204 
205 /**
206  *	acpi_suspend_begin - Set the target system sleep state to the state
207  *		associated with given @pm_state, if supported.
208  */
209 static int acpi_suspend_begin(suspend_state_t pm_state)
210 {
211 	u32 acpi_state = acpi_suspend_states[pm_state];
212 	int error = 0;
213 
214 	error = nvs_nosave ? 0 : suspend_nvs_alloc();
215 	if (error)
216 		return error;
217 
218 	if (sleep_states[acpi_state]) {
219 		acpi_target_sleep_state = acpi_state;
220 		acpi_sleep_tts_switch(acpi_target_sleep_state);
221 	} else {
222 		printk(KERN_ERR "ACPI does not support this state: %d\n",
223 			pm_state);
224 		error = -ENOSYS;
225 	}
226 	return error;
227 }
228 
229 /**
230  *	acpi_suspend_enter - Actually enter a sleep state.
231  *	@pm_state: ignored
232  *
233  *	Flush caches and go to sleep. For STR we have to call arch-specific
234  *	assembly, which in turn call acpi_enter_sleep_state().
235  *	It's unfortunate, but it works. Please fix if you're feeling frisky.
236  */
237 static int acpi_suspend_enter(suspend_state_t pm_state)
238 {
239 	acpi_status status = AE_OK;
240 	unsigned long flags = 0;
241 	u32 acpi_state = acpi_target_sleep_state;
242 
243 	ACPI_FLUSH_CPU_CACHE();
244 
245 	/* Do arch specific saving of state. */
246 	if (acpi_state == ACPI_STATE_S3) {
247 		int error = acpi_save_state_mem();
248 
249 		if (error)
250 			return error;
251 	}
252 
253 	local_irq_save(flags);
254 	acpi_enable_wakeup_device(acpi_state);
255 	switch (acpi_state) {
256 	case ACPI_STATE_S1:
257 		barrier();
258 		status = acpi_enter_sleep_state(acpi_state);
259 		break;
260 
261 	case ACPI_STATE_S3:
262 		do_suspend_lowlevel();
263 		break;
264 	}
265 
266 	/* This violates the spec but is required for bug compatibility. */
267 	acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
268 
269 	/* Reprogram control registers and execute _BFS */
270 	acpi_leave_sleep_state_prep(acpi_state);
271 
272 	/* ACPI 3.0 specs (P62) says that it's the responsibility
273 	 * of the OSPM to clear the status bit [ implying that the
274 	 * POWER_BUTTON event should not reach userspace ]
275 	 */
276 	if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
277 		acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
278 
279 	/*
280 	 * Disable and clear GPE status before interrupt is enabled. Some GPEs
281 	 * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
282 	 * acpi_leave_sleep_state will reenable specific GPEs later
283 	 */
284 	acpi_disable_all_gpes();
285 	/* Allow EC transactions to happen. */
286 	acpi_ec_unblock_transactions_early();
287 
288 	local_irq_restore(flags);
289 	printk(KERN_DEBUG "Back to C!\n");
290 
291 	/* restore processor state */
292 	if (acpi_state == ACPI_STATE_S3)
293 		acpi_restore_state_mem();
294 
295 	suspend_nvs_restore();
296 
297 	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
298 }
299 
300 static void acpi_suspend_finish(void)
301 {
302 	acpi_pm_finish();
303 }
304 
305 static int acpi_suspend_state_valid(suspend_state_t pm_state)
306 {
307 	u32 acpi_state;
308 
309 	switch (pm_state) {
310 	case PM_SUSPEND_ON:
311 	case PM_SUSPEND_STANDBY:
312 	case PM_SUSPEND_MEM:
313 		acpi_state = acpi_suspend_states[pm_state];
314 
315 		return sleep_states[acpi_state];
316 	default:
317 		return 0;
318 	}
319 }
320 
321 static struct platform_suspend_ops acpi_suspend_ops = {
322 	.valid = acpi_suspend_state_valid,
323 	.begin = acpi_suspend_begin,
324 	.prepare_late = acpi_pm_prepare,
325 	.enter = acpi_suspend_enter,
326 	.wake = acpi_suspend_finish,
327 	.end = acpi_pm_end,
328 };
329 
330 /**
331  *	acpi_suspend_begin_old - Set the target system sleep state to the
332  *		state associated with given @pm_state, if supported, and
333  *		execute the _PTS control method.  This function is used if the
334  *		pre-ACPI 2.0 suspend ordering has been requested.
335  */
336 static int acpi_suspend_begin_old(suspend_state_t pm_state)
337 {
338 	int error = acpi_suspend_begin(pm_state);
339 
340 	if (!error)
341 		error = __acpi_pm_prepare();
342 	return error;
343 }
344 
345 /*
346  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
347  * been requested.
348  */
349 static struct platform_suspend_ops acpi_suspend_ops_old = {
350 	.valid = acpi_suspend_state_valid,
351 	.begin = acpi_suspend_begin_old,
352 	.prepare_late = acpi_pm_freeze,
353 	.enter = acpi_suspend_enter,
354 	.wake = acpi_suspend_finish,
355 	.end = acpi_pm_end,
356 	.recover = acpi_pm_finish,
357 };
358 
359 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
360 {
361 	old_suspend_ordering = true;
362 	return 0;
363 }
364 
365 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
366 	{
367 	.callback = init_old_suspend_ordering,
368 	.ident = "Abit KN9 (nForce4 variant)",
369 	.matches = {
370 		DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
371 		DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
372 		},
373 	},
374 	{
375 	.callback = init_old_suspend_ordering,
376 	.ident = "HP xw4600 Workstation",
377 	.matches = {
378 		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
379 		DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
380 		},
381 	},
382 	{
383 	.callback = init_old_suspend_ordering,
384 	.ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
385 	.matches = {
386 		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
387 		DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
388 		},
389 	},
390 	{
391 	.callback = init_old_suspend_ordering,
392 	.ident = "Panasonic CF51-2L",
393 	.matches = {
394 		DMI_MATCH(DMI_BOARD_VENDOR,
395 				"Matsushita Electric Industrial Co.,Ltd."),
396 		DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
397 		},
398 	},
399 	{},
400 };
401 #endif /* CONFIG_SUSPEND */
402 
403 #ifdef CONFIG_HIBERNATION
404 static unsigned long s4_hardware_signature;
405 static struct acpi_table_facs *facs;
406 static bool nosigcheck;
407 
408 void __init acpi_no_s4_hw_signature(void)
409 {
410 	nosigcheck = true;
411 }
412 
413 static int acpi_hibernation_begin(void)
414 {
415 	int error;
416 
417 	error = nvs_nosave ? 0 : suspend_nvs_alloc();
418 	if (!error) {
419 		acpi_target_sleep_state = ACPI_STATE_S4;
420 		acpi_sleep_tts_switch(acpi_target_sleep_state);
421 	}
422 
423 	return error;
424 }
425 
426 static int acpi_hibernation_pre_snapshot(void)
427 {
428 	int error = acpi_pm_prepare();
429 
430 	if (!error)
431 		suspend_nvs_save();
432 
433 	return error;
434 }
435 
436 static int acpi_hibernation_enter(void)
437 {
438 	acpi_status status = AE_OK;
439 	unsigned long flags = 0;
440 
441 	ACPI_FLUSH_CPU_CACHE();
442 
443 	local_irq_save(flags);
444 	acpi_enable_wakeup_device(ACPI_STATE_S4);
445 	/* This shouldn't return.  If it returns, we have a problem */
446 	status = acpi_enter_sleep_state(ACPI_STATE_S4);
447 	/* Reprogram control registers and execute _BFS */
448 	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
449 	local_irq_restore(flags);
450 
451 	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
452 }
453 
454 static void acpi_hibernation_leave(void)
455 {
456 	/*
457 	 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
458 	 * enable it here.
459 	 */
460 	acpi_enable();
461 	/* Reprogram control registers and execute _BFS */
462 	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
463 	/* Check the hardware signature */
464 	if (facs && s4_hardware_signature != facs->hardware_signature) {
465 		printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
466 			"cannot resume!\n");
467 		panic("ACPI S4 hardware signature mismatch");
468 	}
469 	/* Restore the NVS memory area */
470 	suspend_nvs_restore();
471 	/* Allow EC transactions to happen. */
472 	acpi_ec_unblock_transactions_early();
473 }
474 
475 static void acpi_pm_thaw(void)
476 {
477 	acpi_ec_unblock_transactions();
478 	acpi_enable_all_runtime_gpes();
479 }
480 
481 static struct platform_hibernation_ops acpi_hibernation_ops = {
482 	.begin = acpi_hibernation_begin,
483 	.end = acpi_pm_end,
484 	.pre_snapshot = acpi_hibernation_pre_snapshot,
485 	.finish = acpi_pm_finish,
486 	.prepare = acpi_pm_prepare,
487 	.enter = acpi_hibernation_enter,
488 	.leave = acpi_hibernation_leave,
489 	.pre_restore = acpi_pm_freeze,
490 	.restore_cleanup = acpi_pm_thaw,
491 };
492 
493 /**
494  *	acpi_hibernation_begin_old - Set the target system sleep state to
495  *		ACPI_STATE_S4 and execute the _PTS control method.  This
496  *		function is used if the pre-ACPI 2.0 suspend ordering has been
497  *		requested.
498  */
499 static int acpi_hibernation_begin_old(void)
500 {
501 	int error;
502 	/*
503 	 * The _TTS object should always be evaluated before the _PTS object.
504 	 * When the old_suspended_ordering is true, the _PTS object is
505 	 * evaluated in the acpi_sleep_prepare.
506 	 */
507 	acpi_sleep_tts_switch(ACPI_STATE_S4);
508 
509 	error = acpi_sleep_prepare(ACPI_STATE_S4);
510 
511 	if (!error) {
512 		if (!nvs_nosave)
513 			error = suspend_nvs_alloc();
514 		if (!error)
515 			acpi_target_sleep_state = ACPI_STATE_S4;
516 	}
517 	return error;
518 }
519 
520 static int acpi_hibernation_pre_snapshot_old(void)
521 {
522 	acpi_pm_freeze();
523 	suspend_nvs_save();
524 	return 0;
525 }
526 
527 /*
528  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
529  * been requested.
530  */
531 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
532 	.begin = acpi_hibernation_begin_old,
533 	.end = acpi_pm_end,
534 	.pre_snapshot = acpi_hibernation_pre_snapshot_old,
535 	.prepare = acpi_pm_freeze,
536 	.finish = acpi_pm_finish,
537 	.enter = acpi_hibernation_enter,
538 	.leave = acpi_hibernation_leave,
539 	.pre_restore = acpi_pm_freeze,
540 	.restore_cleanup = acpi_pm_thaw,
541 	.recover = acpi_pm_finish,
542 };
543 #endif /* CONFIG_HIBERNATION */
544 
545 int acpi_suspend(u32 acpi_state)
546 {
547 	suspend_state_t states[] = {
548 		[1] = PM_SUSPEND_STANDBY,
549 		[3] = PM_SUSPEND_MEM,
550 		[5] = PM_SUSPEND_MAX
551 	};
552 
553 	if (acpi_state < 6 && states[acpi_state])
554 		return pm_suspend(states[acpi_state]);
555 	if (acpi_state == 4)
556 		return hibernate();
557 	return -EINVAL;
558 }
559 
560 #ifdef CONFIG_PM_SLEEP
561 /**
562  *	acpi_pm_device_sleep_state - return preferred power state of ACPI device
563  *		in the system sleep state given by %acpi_target_sleep_state
564  *	@dev: device to examine; its driver model wakeup flags control
565  *		whether it should be able to wake up the system
566  *	@d_min_p: used to store the upper limit of allowed states range
567  *	Return value: preferred power state of the device on success, -ENODEV on
568  *		failure (ie. if there's no 'struct acpi_device' for @dev)
569  *
570  *	Find the lowest power (highest number) ACPI device power state that
571  *	device @dev can be in while the system is in the sleep state represented
572  *	by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
573  *	able to wake up the system from this sleep state.  If @d_min_p is set,
574  *	the highest power (lowest number) device power state of @dev allowed
575  *	in this system sleep state is stored at the location pointed to by it.
576  *
577  *	The caller must ensure that @dev is valid before using this function.
578  *	The caller is also responsible for figuring out if the device is
579  *	supposed to be able to wake up the system and passing this information
580  *	via @wake.
581  */
582 
583 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
584 {
585 	acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
586 	struct acpi_device *adev;
587 	char acpi_method[] = "_SxD";
588 	unsigned long long d_min, d_max;
589 
590 	if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
591 		printk(KERN_DEBUG "ACPI handle has no context!\n");
592 		return -ENODEV;
593 	}
594 
595 	acpi_method[2] = '0' + acpi_target_sleep_state;
596 	/*
597 	 * If the sleep state is S0, we will return D3, but if the device has
598 	 * _S0W, we will use the value from _S0W
599 	 */
600 	d_min = ACPI_STATE_D0;
601 	d_max = ACPI_STATE_D3;
602 
603 	/*
604 	 * If present, _SxD methods return the minimum D-state (highest power
605 	 * state) we can use for the corresponding S-states.  Otherwise, the
606 	 * minimum D-state is D0 (ACPI 3.x).
607 	 *
608 	 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
609 	 * provided -- that's our fault recovery, we ignore retval.
610 	 */
611 	if (acpi_target_sleep_state > ACPI_STATE_S0)
612 		acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
613 
614 	/*
615 	 * If _PRW says we can wake up the system from the target sleep state,
616 	 * the D-state returned by _SxD is sufficient for that (we assume a
617 	 * wakeup-aware driver if wake is set).  Still, if _SxW exists
618 	 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
619 	 * can wake the system.  _S0W may be valid, too.
620 	 */
621 	if (acpi_target_sleep_state == ACPI_STATE_S0 ||
622 	    (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
623 	     adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
624 		acpi_status status;
625 
626 		acpi_method[3] = 'W';
627 		status = acpi_evaluate_integer(handle, acpi_method, NULL,
628 						&d_max);
629 		if (ACPI_FAILURE(status)) {
630 			d_max = d_min;
631 		} else if (d_max < d_min) {
632 			/* Warn the user of the broken DSDT */
633 			printk(KERN_WARNING "ACPI: Wrong value from %s\n",
634 				acpi_method);
635 			/* Sanitize it */
636 			d_min = d_max;
637 		}
638 	}
639 
640 	if (d_min_p)
641 		*d_min_p = d_min;
642 	return d_max;
643 }
644 
645 /**
646  *	acpi_pm_device_sleep_wake - enable or disable the system wake-up
647  *                                  capability of given device
648  *	@dev: device to handle
649  *	@enable: 'true' - enable, 'false' - disable the wake-up capability
650  */
651 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
652 {
653 	acpi_handle handle;
654 	struct acpi_device *adev;
655 	int error;
656 
657 	if (!device_can_wakeup(dev))
658 		return -EINVAL;
659 
660 	handle = DEVICE_ACPI_HANDLE(dev);
661 	if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
662 		dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
663 		return -ENODEV;
664 	}
665 
666 	error = enable ?
667 		acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
668 		acpi_disable_wakeup_device_power(adev);
669 	if (!error)
670 		dev_info(dev, "wake-up capability %s by ACPI\n",
671 				enable ? "enabled" : "disabled");
672 
673 	return error;
674 }
675 #endif
676 
677 static void acpi_power_off_prepare(void)
678 {
679 	/* Prepare to power off the system */
680 	acpi_sleep_prepare(ACPI_STATE_S5);
681 	acpi_disable_all_gpes();
682 }
683 
684 static void acpi_power_off(void)
685 {
686 	/* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
687 	printk(KERN_DEBUG "%s called\n", __func__);
688 	local_irq_disable();
689 	acpi_enable_wakeup_device(ACPI_STATE_S5);
690 	acpi_enter_sleep_state(ACPI_STATE_S5);
691 }
692 
693 /*
694  * ACPI 2.0 created the optional _GTS and _BFS,
695  * but industry adoption has been neither rapid nor broad.
696  *
697  * Linux gets into trouble when it executes poorly validated
698  * paths through the BIOS, so disable _GTS and _BFS by default,
699  * but do speak up and offer the option to enable them.
700  */
701 void __init acpi_gts_bfs_check(void)
702 {
703 	acpi_handle dummy;
704 
705 	if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
706 	{
707 		printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
708 		printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
709 			"please notify linux-acpi@vger.kernel.org\n");
710 	}
711 	if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
712 	{
713 		printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
714 		printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
715 			"please notify linux-acpi@vger.kernel.org\n");
716 	}
717 }
718 
719 int __init acpi_sleep_init(void)
720 {
721 	acpi_status status;
722 	u8 type_a, type_b;
723 #ifdef CONFIG_SUSPEND
724 	int i = 0;
725 
726 	dmi_check_system(acpisleep_dmi_table);
727 #endif
728 
729 	if (acpi_disabled)
730 		return 0;
731 
732 	sleep_states[ACPI_STATE_S0] = 1;
733 	printk(KERN_INFO PREFIX "(supports S0");
734 
735 #ifdef CONFIG_SUSPEND
736 	for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
737 		status = acpi_get_sleep_type_data(i, &type_a, &type_b);
738 		if (ACPI_SUCCESS(status)) {
739 			sleep_states[i] = 1;
740 			printk(" S%d", i);
741 		}
742 	}
743 
744 	suspend_set_ops(old_suspend_ordering ?
745 		&acpi_suspend_ops_old : &acpi_suspend_ops);
746 #endif
747 
748 #ifdef CONFIG_HIBERNATION
749 	status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
750 	if (ACPI_SUCCESS(status)) {
751 		hibernation_set_ops(old_suspend_ordering ?
752 			&acpi_hibernation_ops_old : &acpi_hibernation_ops);
753 		sleep_states[ACPI_STATE_S4] = 1;
754 		printk(" S4");
755 		if (!nosigcheck) {
756 			acpi_get_table(ACPI_SIG_FACS, 1,
757 				(struct acpi_table_header **)&facs);
758 			if (facs)
759 				s4_hardware_signature =
760 					facs->hardware_signature;
761 		}
762 	}
763 #endif
764 	status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
765 	if (ACPI_SUCCESS(status)) {
766 		sleep_states[ACPI_STATE_S5] = 1;
767 		printk(" S5");
768 		pm_power_off_prepare = acpi_power_off_prepare;
769 		pm_power_off = acpi_power_off;
770 	}
771 	printk(")\n");
772 	/*
773 	 * Register the tts_notifier to reboot notifier list so that the _TTS
774 	 * object can also be evaluated when the system enters S5.
775 	 */
776 	register_reboot_notifier(&tts_notifier);
777 	acpi_gts_bfs_check();
778 	return 0;
779 }
780