xref: /linux/drivers/acpi/sleep.c (revision 36239c6704b71da7fb8e2a9429e159a84d0c5a3e)
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  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
86  * user to request that behavior by using the 'acpi_old_suspend_ordering'
87  * kernel command line option that causes the following variable to be set.
88  */
89 static bool old_suspend_ordering;
90 
91 void __init acpi_old_suspend_ordering(void)
92 {
93 	old_suspend_ordering = true;
94 }
95 
96 /**
97  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
98  */
99 static int acpi_pm_freeze(void)
100 {
101 	acpi_disable_all_gpes();
102 	acpi_os_wait_events_complete(NULL);
103 	acpi_ec_block_transactions();
104 	return 0;
105 }
106 
107 /**
108  *	__acpi_pm_prepare - Prepare the platform to enter the target state.
109  *
110  *	If necessary, set the firmware waking vector and do arch-specific
111  *	nastiness to get the wakeup code to the waking vector.
112  */
113 static int __acpi_pm_prepare(void)
114 {
115 	int error = acpi_sleep_prepare(acpi_target_sleep_state);
116 
117 	suspend_nvs_save();
118 
119 	if (error)
120 		acpi_target_sleep_state = ACPI_STATE_S0;
121 	return error;
122 }
123 
124 /**
125  *	acpi_pm_prepare - Prepare the platform to enter the target sleep
126  *		state and disable the GPEs.
127  */
128 static int acpi_pm_prepare(void)
129 {
130 	int error = __acpi_pm_prepare();
131 
132 	if (!error)
133 		acpi_pm_freeze();
134 
135 	return error;
136 }
137 
138 /**
139  *	acpi_pm_finish - Instruct the platform to leave a sleep state.
140  *
141  *	This is called after we wake back up (or if entering the sleep state
142  *	failed).
143  */
144 static void acpi_pm_finish(void)
145 {
146 	u32 acpi_state = acpi_target_sleep_state;
147 
148 	suspend_nvs_free();
149 	acpi_ec_unblock_transactions();
150 
151 	if (acpi_state == ACPI_STATE_S0)
152 		return;
153 
154 	printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
155 		acpi_state);
156 	acpi_disable_wakeup_device(acpi_state);
157 	acpi_leave_sleep_state(acpi_state);
158 
159 	/* reset firmware waking vector */
160 	acpi_set_firmware_waking_vector((acpi_physical_address) 0);
161 
162 	acpi_target_sleep_state = ACPI_STATE_S0;
163 }
164 
165 /**
166  *	acpi_pm_end - Finish up suspend sequence.
167  */
168 static void acpi_pm_end(void)
169 {
170 	/*
171 	 * This is necessary in case acpi_pm_finish() is not called during a
172 	 * failing transition to a sleep state.
173 	 */
174 	acpi_target_sleep_state = ACPI_STATE_S0;
175 	acpi_sleep_tts_switch(acpi_target_sleep_state);
176 }
177 #else /* !CONFIG_ACPI_SLEEP */
178 #define acpi_target_sleep_state	ACPI_STATE_S0
179 #endif /* CONFIG_ACPI_SLEEP */
180 
181 #ifdef CONFIG_SUSPEND
182 extern void do_suspend_lowlevel(void);
183 
184 static u32 acpi_suspend_states[] = {
185 	[PM_SUSPEND_ON] = ACPI_STATE_S0,
186 	[PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
187 	[PM_SUSPEND_MEM] = ACPI_STATE_S3,
188 	[PM_SUSPEND_MAX] = ACPI_STATE_S5
189 };
190 
191 /**
192  *	acpi_suspend_begin - Set the target system sleep state to the state
193  *		associated with given @pm_state, if supported.
194  */
195 static int acpi_suspend_begin(suspend_state_t pm_state)
196 {
197 	u32 acpi_state = acpi_suspend_states[pm_state];
198 	int error = 0;
199 
200 	error = suspend_nvs_alloc();
201 
202 	if (error)
203 		return error;
204 
205 	if (sleep_states[acpi_state]) {
206 		acpi_target_sleep_state = acpi_state;
207 		acpi_sleep_tts_switch(acpi_target_sleep_state);
208 	} else {
209 		printk(KERN_ERR "ACPI does not support this state: %d\n",
210 			pm_state);
211 		error = -ENOSYS;
212 	}
213 	return error;
214 }
215 
216 /**
217  *	acpi_suspend_enter - Actually enter a sleep state.
218  *	@pm_state: ignored
219  *
220  *	Flush caches and go to sleep. For STR we have to call arch-specific
221  *	assembly, which in turn call acpi_enter_sleep_state().
222  *	It's unfortunate, but it works. Please fix if you're feeling frisky.
223  */
224 static int acpi_suspend_enter(suspend_state_t pm_state)
225 {
226 	acpi_status status = AE_OK;
227 	unsigned long flags = 0;
228 	u32 acpi_state = acpi_target_sleep_state;
229 
230 	ACPI_FLUSH_CPU_CACHE();
231 
232 	/* Do arch specific saving of state. */
233 	if (acpi_state == ACPI_STATE_S3) {
234 		int error = acpi_save_state_mem();
235 
236 		if (error)
237 			return error;
238 	}
239 
240 	local_irq_save(flags);
241 	acpi_enable_wakeup_device(acpi_state);
242 	switch (acpi_state) {
243 	case ACPI_STATE_S1:
244 		barrier();
245 		status = acpi_enter_sleep_state(acpi_state);
246 		break;
247 
248 	case ACPI_STATE_S3:
249 		do_suspend_lowlevel();
250 		break;
251 	}
252 
253 	/* This violates the spec but is required for bug compatibility. */
254 	acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
255 
256 	/* Reprogram control registers and execute _BFS */
257 	acpi_leave_sleep_state_prep(acpi_state);
258 
259 	/* ACPI 3.0 specs (P62) says that it's the responsibility
260 	 * of the OSPM to clear the status bit [ implying that the
261 	 * POWER_BUTTON event should not reach userspace ]
262 	 */
263 	if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
264 		acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
265 
266 	/*
267 	 * Disable and clear GPE status before interrupt is enabled. Some GPEs
268 	 * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
269 	 * acpi_leave_sleep_state will reenable specific GPEs later
270 	 */
271 	acpi_disable_all_gpes();
272 	/* Allow EC transactions to happen. */
273 	acpi_ec_unblock_transactions_early();
274 
275 	local_irq_restore(flags);
276 	printk(KERN_DEBUG "Back to C!\n");
277 
278 	/* restore processor state */
279 	if (acpi_state == ACPI_STATE_S3)
280 		acpi_restore_state_mem();
281 
282 	suspend_nvs_restore();
283 
284 	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
285 }
286 
287 static void acpi_suspend_finish(void)
288 {
289 	acpi_pm_finish();
290 }
291 
292 static int acpi_suspend_state_valid(suspend_state_t pm_state)
293 {
294 	u32 acpi_state;
295 
296 	switch (pm_state) {
297 	case PM_SUSPEND_ON:
298 	case PM_SUSPEND_STANDBY:
299 	case PM_SUSPEND_MEM:
300 		acpi_state = acpi_suspend_states[pm_state];
301 
302 		return sleep_states[acpi_state];
303 	default:
304 		return 0;
305 	}
306 }
307 
308 static struct platform_suspend_ops acpi_suspend_ops = {
309 	.valid = acpi_suspend_state_valid,
310 	.begin = acpi_suspend_begin,
311 	.prepare_late = acpi_pm_prepare,
312 	.enter = acpi_suspend_enter,
313 	.wake = acpi_suspend_finish,
314 	.end = acpi_pm_end,
315 };
316 
317 /**
318  *	acpi_suspend_begin_old - Set the target system sleep state to the
319  *		state associated with given @pm_state, if supported, and
320  *		execute the _PTS control method.  This function is used if the
321  *		pre-ACPI 2.0 suspend ordering has been requested.
322  */
323 static int acpi_suspend_begin_old(suspend_state_t pm_state)
324 {
325 	int error = acpi_suspend_begin(pm_state);
326 
327 	if (!error)
328 		error = __acpi_pm_prepare();
329 	return error;
330 }
331 
332 /*
333  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
334  * been requested.
335  */
336 static struct platform_suspend_ops acpi_suspend_ops_old = {
337 	.valid = acpi_suspend_state_valid,
338 	.begin = acpi_suspend_begin_old,
339 	.prepare_late = acpi_pm_freeze,
340 	.enter = acpi_suspend_enter,
341 	.wake = acpi_suspend_finish,
342 	.end = acpi_pm_end,
343 	.recover = acpi_pm_finish,
344 };
345 
346 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
347 {
348 	old_suspend_ordering = true;
349 	return 0;
350 }
351 
352 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
353 	{
354 	.callback = init_old_suspend_ordering,
355 	.ident = "Abit KN9 (nForce4 variant)",
356 	.matches = {
357 		DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
358 		DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
359 		},
360 	},
361 	{
362 	.callback = init_old_suspend_ordering,
363 	.ident = "HP xw4600 Workstation",
364 	.matches = {
365 		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
366 		DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
367 		},
368 	},
369 	{
370 	.callback = init_old_suspend_ordering,
371 	.ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
372 	.matches = {
373 		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
374 		DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
375 		},
376 	},
377 	{
378 	.callback = init_old_suspend_ordering,
379 	.ident = "Panasonic CF51-2L",
380 	.matches = {
381 		DMI_MATCH(DMI_BOARD_VENDOR,
382 				"Matsushita Electric Industrial Co.,Ltd."),
383 		DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
384 		},
385 	},
386 	{},
387 };
388 #endif /* CONFIG_SUSPEND */
389 
390 #ifdef CONFIG_HIBERNATION
391 /*
392  * The ACPI specification wants us to save NVS memory regions during hibernation
393  * and to restore them during the subsequent resume.  However, it is not certain
394  * if this mechanism is going to work on all machines, so we allow the user to
395  * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
396  * option.
397  */
398 static bool s4_no_nvs;
399 
400 void __init acpi_s4_no_nvs(void)
401 {
402 	s4_no_nvs = true;
403 }
404 
405 static unsigned long s4_hardware_signature;
406 static struct acpi_table_facs *facs;
407 static bool nosigcheck;
408 
409 void __init acpi_no_s4_hw_signature(void)
410 {
411 	nosigcheck = true;
412 }
413 
414 static int acpi_hibernation_begin(void)
415 {
416 	int error;
417 
418 	error = s4_no_nvs ? 0 : suspend_nvs_alloc();
419 	if (!error) {
420 		acpi_target_sleep_state = ACPI_STATE_S4;
421 		acpi_sleep_tts_switch(acpi_target_sleep_state);
422 	}
423 
424 	return error;
425 }
426 
427 static int acpi_hibernation_pre_snapshot(void)
428 {
429 	int error = acpi_pm_prepare();
430 
431 	if (!error)
432 		suspend_nvs_save();
433 
434 	return error;
435 }
436 
437 static int acpi_hibernation_enter(void)
438 {
439 	acpi_status status = AE_OK;
440 	unsigned long flags = 0;
441 
442 	ACPI_FLUSH_CPU_CACHE();
443 
444 	local_irq_save(flags);
445 	acpi_enable_wakeup_device(ACPI_STATE_S4);
446 	/* This shouldn't return.  If it returns, we have a problem */
447 	status = acpi_enter_sleep_state(ACPI_STATE_S4);
448 	/* Reprogram control registers and execute _BFS */
449 	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
450 	local_irq_restore(flags);
451 
452 	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
453 }
454 
455 static void acpi_hibernation_leave(void)
456 {
457 	/*
458 	 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
459 	 * enable it here.
460 	 */
461 	acpi_enable();
462 	/* Reprogram control registers and execute _BFS */
463 	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
464 	/* Check the hardware signature */
465 	if (facs && s4_hardware_signature != facs->hardware_signature) {
466 		printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
467 			"cannot resume!\n");
468 		panic("ACPI S4 hardware signature mismatch");
469 	}
470 	/* Restore the NVS memory area */
471 	suspend_nvs_restore();
472 	/* Allow EC transactions to happen. */
473 	acpi_ec_unblock_transactions_early();
474 }
475 
476 static void acpi_pm_thaw(void)
477 {
478 	acpi_ec_unblock_transactions();
479 	acpi_enable_all_runtime_gpes();
480 }
481 
482 static struct platform_hibernation_ops acpi_hibernation_ops = {
483 	.begin = acpi_hibernation_begin,
484 	.end = acpi_pm_end,
485 	.pre_snapshot = acpi_hibernation_pre_snapshot,
486 	.finish = acpi_pm_finish,
487 	.prepare = acpi_pm_prepare,
488 	.enter = acpi_hibernation_enter,
489 	.leave = acpi_hibernation_leave,
490 	.pre_restore = acpi_pm_freeze,
491 	.restore_cleanup = acpi_pm_thaw,
492 };
493 
494 /**
495  *	acpi_hibernation_begin_old - Set the target system sleep state to
496  *		ACPI_STATE_S4 and execute the _PTS control method.  This
497  *		function is used if the pre-ACPI 2.0 suspend ordering has been
498  *		requested.
499  */
500 static int acpi_hibernation_begin_old(void)
501 {
502 	int error;
503 	/*
504 	 * The _TTS object should always be evaluated before the _PTS object.
505 	 * When the old_suspended_ordering is true, the _PTS object is
506 	 * evaluated in the acpi_sleep_prepare.
507 	 */
508 	acpi_sleep_tts_switch(ACPI_STATE_S4);
509 
510 	error = acpi_sleep_prepare(ACPI_STATE_S4);
511 
512 	if (!error) {
513 		if (!s4_no_nvs)
514 			error = suspend_nvs_alloc();
515 		if (!error)
516 			acpi_target_sleep_state = ACPI_STATE_S4;
517 	}
518 	return error;
519 }
520 
521 static int acpi_hibernation_pre_snapshot_old(void)
522 {
523 	acpi_pm_freeze();
524 	suspend_nvs_save();
525 	return 0;
526 }
527 
528 /*
529  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
530  * been requested.
531  */
532 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
533 	.begin = acpi_hibernation_begin_old,
534 	.end = acpi_pm_end,
535 	.pre_snapshot = acpi_hibernation_pre_snapshot_old,
536 	.prepare = acpi_pm_freeze,
537 	.finish = acpi_pm_finish,
538 	.enter = acpi_hibernation_enter,
539 	.leave = acpi_hibernation_leave,
540 	.pre_restore = acpi_pm_freeze,
541 	.restore_cleanup = acpi_pm_thaw,
542 	.recover = acpi_pm_finish,
543 };
544 #endif /* CONFIG_HIBERNATION */
545 
546 int acpi_suspend(u32 acpi_state)
547 {
548 	suspend_state_t states[] = {
549 		[1] = PM_SUSPEND_STANDBY,
550 		[3] = PM_SUSPEND_MEM,
551 		[5] = PM_SUSPEND_MAX
552 	};
553 
554 	if (acpi_state < 6 && states[acpi_state])
555 		return pm_suspend(states[acpi_state]);
556 	if (acpi_state == 4)
557 		return hibernate();
558 	return -EINVAL;
559 }
560 
561 #ifdef CONFIG_PM_SLEEP
562 /**
563  *	acpi_pm_device_sleep_state - return preferred power state of ACPI device
564  *		in the system sleep state given by %acpi_target_sleep_state
565  *	@dev: device to examine; its driver model wakeup flags control
566  *		whether it should be able to wake up the system
567  *	@d_min_p: used to store the upper limit of allowed states range
568  *	Return value: preferred power state of the device on success, -ENODEV on
569  *		failure (ie. if there's no 'struct acpi_device' for @dev)
570  *
571  *	Find the lowest power (highest number) ACPI device power state that
572  *	device @dev can be in while the system is in the sleep state represented
573  *	by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
574  *	able to wake up the system from this sleep state.  If @d_min_p is set,
575  *	the highest power (lowest number) device power state of @dev allowed
576  *	in this system sleep state is stored at the location pointed to by it.
577  *
578  *	The caller must ensure that @dev is valid before using this function.
579  *	The caller is also responsible for figuring out if the device is
580  *	supposed to be able to wake up the system and passing this information
581  *	via @wake.
582  */
583 
584 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
585 {
586 	acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
587 	struct acpi_device *adev;
588 	char acpi_method[] = "_SxD";
589 	unsigned long long d_min, d_max;
590 
591 	if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
592 		printk(KERN_DEBUG "ACPI handle has no context!\n");
593 		return -ENODEV;
594 	}
595 
596 	acpi_method[2] = '0' + acpi_target_sleep_state;
597 	/*
598 	 * If the sleep state is S0, we will return D3, but if the device has
599 	 * _S0W, we will use the value from _S0W
600 	 */
601 	d_min = ACPI_STATE_D0;
602 	d_max = ACPI_STATE_D3;
603 
604 	/*
605 	 * If present, _SxD methods return the minimum D-state (highest power
606 	 * state) we can use for the corresponding S-states.  Otherwise, the
607 	 * minimum D-state is D0 (ACPI 3.x).
608 	 *
609 	 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
610 	 * provided -- that's our fault recovery, we ignore retval.
611 	 */
612 	if (acpi_target_sleep_state > ACPI_STATE_S0)
613 		acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
614 
615 	/*
616 	 * If _PRW says we can wake up the system from the target sleep state,
617 	 * the D-state returned by _SxD is sufficient for that (we assume a
618 	 * wakeup-aware driver if wake is set).  Still, if _SxW exists
619 	 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
620 	 * can wake the system.  _S0W may be valid, too.
621 	 */
622 	if (acpi_target_sleep_state == ACPI_STATE_S0 ||
623 	    (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
624 	     adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
625 		acpi_status status;
626 
627 		acpi_method[3] = 'W';
628 		status = acpi_evaluate_integer(handle, acpi_method, NULL,
629 						&d_max);
630 		if (ACPI_FAILURE(status)) {
631 			d_max = d_min;
632 		} else if (d_max < d_min) {
633 			/* Warn the user of the broken DSDT */
634 			printk(KERN_WARNING "ACPI: Wrong value from %s\n",
635 				acpi_method);
636 			/* Sanitize it */
637 			d_min = d_max;
638 		}
639 	}
640 
641 	if (d_min_p)
642 		*d_min_p = d_min;
643 	return d_max;
644 }
645 
646 /**
647  *	acpi_pm_device_sleep_wake - enable or disable the system wake-up
648  *                                  capability of given device
649  *	@dev: device to handle
650  *	@enable: 'true' - enable, 'false' - disable the wake-up capability
651  */
652 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
653 {
654 	acpi_handle handle;
655 	struct acpi_device *adev;
656 	int error;
657 
658 	if (!device_can_wakeup(dev))
659 		return -EINVAL;
660 
661 	handle = DEVICE_ACPI_HANDLE(dev);
662 	if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
663 		dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
664 		return -ENODEV;
665 	}
666 
667 	if (enable) {
668 		error = acpi_enable_wakeup_device_power(adev,
669 						acpi_target_sleep_state);
670 		if (!error)
671 			acpi_enable_gpe(adev->wakeup.gpe_device,
672 					adev->wakeup.gpe_number,
673 					ACPI_GPE_TYPE_WAKE);
674 	} else {
675 		acpi_disable_gpe(adev->wakeup.gpe_device, adev->wakeup.gpe_number,
676 				ACPI_GPE_TYPE_WAKE);
677 		error = acpi_disable_wakeup_device_power(adev);
678 	}
679 	if (!error)
680 		dev_info(dev, "wake-up capability %s by ACPI\n",
681 				enable ? "enabled" : "disabled");
682 
683 	return error;
684 }
685 #endif
686 
687 static void acpi_power_off_prepare(void)
688 {
689 	/* Prepare to power off the system */
690 	acpi_sleep_prepare(ACPI_STATE_S5);
691 	acpi_disable_all_gpes();
692 }
693 
694 static void acpi_power_off(void)
695 {
696 	/* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
697 	printk(KERN_DEBUG "%s called\n", __func__);
698 	local_irq_disable();
699 	acpi_enable_wakeup_device(ACPI_STATE_S5);
700 	acpi_enter_sleep_state(ACPI_STATE_S5);
701 }
702 
703 /*
704  * ACPI 2.0 created the optional _GTS and _BFS,
705  * but industry adoption has been neither rapid nor broad.
706  *
707  * Linux gets into trouble when it executes poorly validated
708  * paths through the BIOS, so disable _GTS and _BFS by default,
709  * but do speak up and offer the option to enable them.
710  */
711 void __init acpi_gts_bfs_check(void)
712 {
713 	acpi_handle dummy;
714 
715 	if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
716 	{
717 		printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
718 		printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
719 			"please notify linux-acpi@vger.kernel.org\n");
720 	}
721 	if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
722 	{
723 		printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
724 		printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
725 			"please notify linux-acpi@vger.kernel.org\n");
726 	}
727 }
728 
729 int __init acpi_sleep_init(void)
730 {
731 	acpi_status status;
732 	u8 type_a, type_b;
733 #ifdef CONFIG_SUSPEND
734 	int i = 0;
735 
736 	dmi_check_system(acpisleep_dmi_table);
737 #endif
738 
739 	if (acpi_disabled)
740 		return 0;
741 
742 	sleep_states[ACPI_STATE_S0] = 1;
743 	printk(KERN_INFO PREFIX "(supports S0");
744 
745 #ifdef CONFIG_SUSPEND
746 	for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
747 		status = acpi_get_sleep_type_data(i, &type_a, &type_b);
748 		if (ACPI_SUCCESS(status)) {
749 			sleep_states[i] = 1;
750 			printk(" S%d", i);
751 		}
752 	}
753 
754 	suspend_set_ops(old_suspend_ordering ?
755 		&acpi_suspend_ops_old : &acpi_suspend_ops);
756 #endif
757 
758 #ifdef CONFIG_HIBERNATION
759 	status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
760 	if (ACPI_SUCCESS(status)) {
761 		hibernation_set_ops(old_suspend_ordering ?
762 			&acpi_hibernation_ops_old : &acpi_hibernation_ops);
763 		sleep_states[ACPI_STATE_S4] = 1;
764 		printk(" S4");
765 		if (!nosigcheck) {
766 			acpi_get_table(ACPI_SIG_FACS, 1,
767 				(struct acpi_table_header **)&facs);
768 			if (facs)
769 				s4_hardware_signature =
770 					facs->hardware_signature;
771 		}
772 	}
773 #endif
774 	status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
775 	if (ACPI_SUCCESS(status)) {
776 		sleep_states[ACPI_STATE_S5] = 1;
777 		printk(" S5");
778 		pm_power_off_prepare = acpi_power_off_prepare;
779 		pm_power_off = acpi_power_off;
780 	}
781 	printk(")\n");
782 	/*
783 	 * Register the tts_notifier to reboot notifier list so that the _TTS
784 	 * object can also be evaluated when the system enters S5.
785 	 */
786 	register_reboot_notifier(&tts_notifier);
787 	acpi_gts_bfs_check();
788 	return 0;
789 }
790