3ca98686f28b837dbbcb461f77f59009c3ae1644
[safe/jmp/linux-2.6] / drivers / acpi / sleep.c
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 #include "sleep.h"
25
26 u8 sleep_states[ACPI_S_STATE_COUNT];
27
28 static void acpi_sleep_tts_switch(u32 acpi_state)
29 {
30         union acpi_object in_arg = { ACPI_TYPE_INTEGER };
31         struct acpi_object_list arg_list = { 1, &in_arg };
32         acpi_status status = AE_OK;
33
34         in_arg.integer.value = acpi_state;
35         status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
36         if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
37                 /*
38                  * OS can't evaluate the _TTS object correctly. Some warning
39                  * message will be printed. But it won't break anything.
40                  */
41                 printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
42         }
43 }
44
45 static int tts_notify_reboot(struct notifier_block *this,
46                         unsigned long code, void *x)
47 {
48         acpi_sleep_tts_switch(ACPI_STATE_S5);
49         return NOTIFY_DONE;
50 }
51
52 static struct notifier_block tts_notifier = {
53         .notifier_call  = tts_notify_reboot,
54         .next           = NULL,
55         .priority       = 0,
56 };
57
58 static int acpi_sleep_prepare(u32 acpi_state)
59 {
60 #ifdef CONFIG_ACPI_SLEEP
61         /* do we have a wakeup address for S2 and S3? */
62         if (acpi_state == ACPI_STATE_S3) {
63                 if (!acpi_wakeup_address) {
64                         return -EFAULT;
65                 }
66                 acpi_set_firmware_waking_vector(
67                                 (acpi_physical_address)acpi_wakeup_address);
68
69         }
70         ACPI_FLUSH_CPU_CACHE();
71         acpi_enable_wakeup_device_prep(acpi_state);
72 #endif
73         printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
74                 acpi_state);
75         acpi_enter_sleep_state_prep(acpi_state);
76         return 0;
77 }
78
79 #ifdef CONFIG_ACPI_SLEEP
80 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
81 /*
82  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
83  * user to request that behavior by using the 'acpi_old_suspend_ordering'
84  * kernel command line option that causes the following variable to be set.
85  */
86 static bool old_suspend_ordering;
87
88 void __init acpi_old_suspend_ordering(void)
89 {
90         old_suspend_ordering = true;
91 }
92
93 /**
94  *      acpi_pm_disable_gpes - Disable the GPEs.
95  */
96 static int acpi_pm_disable_gpes(void)
97 {
98         acpi_disable_all_gpes();
99         return 0;
100 }
101
102 /**
103  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
104  *
105  *      If necessary, set the firmware waking vector and do arch-specific
106  *      nastiness to get the wakeup code to the waking vector.
107  */
108 static int __acpi_pm_prepare(void)
109 {
110         int error = acpi_sleep_prepare(acpi_target_sleep_state);
111
112         if (error)
113                 acpi_target_sleep_state = ACPI_STATE_S0;
114         return error;
115 }
116
117 /**
118  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
119  *              state and disable the GPEs.
120  */
121 static int acpi_pm_prepare(void)
122 {
123         int error = __acpi_pm_prepare();
124
125         if (!error)
126                 acpi_disable_all_gpes();
127         return error;
128 }
129
130 /**
131  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
132  *
133  *      This is called after we wake back up (or if entering the sleep state
134  *      failed).
135  */
136 static void acpi_pm_finish(void)
137 {
138         u32 acpi_state = acpi_target_sleep_state;
139
140         if (acpi_state == ACPI_STATE_S0)
141                 return;
142
143         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
144                 acpi_state);
145         acpi_disable_wakeup_device(acpi_state);
146         acpi_leave_sleep_state(acpi_state);
147
148         /* reset firmware waking vector */
149         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
150
151         acpi_target_sleep_state = ACPI_STATE_S0;
152 }
153
154 /**
155  *      acpi_pm_end - Finish up suspend sequence.
156  */
157 static void acpi_pm_end(void)
158 {
159         /*
160          * This is necessary in case acpi_pm_finish() is not called during a
161          * failing transition to a sleep state.
162          */
163         acpi_target_sleep_state = ACPI_STATE_S0;
164         acpi_sleep_tts_switch(acpi_target_sleep_state);
165 }
166 #else /* !CONFIG_ACPI_SLEEP */
167 #define acpi_target_sleep_state ACPI_STATE_S0
168 #endif /* CONFIG_ACPI_SLEEP */
169
170 #ifdef CONFIG_SUSPEND
171 /*
172  * According to the ACPI specification the BIOS should make sure that ACPI is
173  * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states.  Still,
174  * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
175  * on such systems during resume.  Unfortunately that doesn't help in
176  * particularly pathological cases in which SCI_EN has to be set directly on
177  * resume, although the specification states very clearly that this flag is
178  * owned by the hardware.  The set_sci_en_on_resume variable will be set in such
179  * cases.
180  */
181 static bool set_sci_en_on_resume;
182
183 extern void do_suspend_lowlevel(void);
184
185 static u32 acpi_suspend_states[] = {
186         [PM_SUSPEND_ON] = ACPI_STATE_S0,
187         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
188         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
189         [PM_SUSPEND_MAX] = ACPI_STATE_S5
190 };
191
192 /**
193  *      acpi_suspend_begin - Set the target system sleep state to the state
194  *              associated with given @pm_state, if supported.
195  */
196 static int acpi_suspend_begin(suspend_state_t pm_state)
197 {
198         u32 acpi_state = acpi_suspend_states[pm_state];
199         int error = 0;
200
201         if (sleep_states[acpi_state]) {
202                 acpi_target_sleep_state = acpi_state;
203                 acpi_sleep_tts_switch(acpi_target_sleep_state);
204         } else {
205                 printk(KERN_ERR "ACPI does not support this state: %d\n",
206                         pm_state);
207                 error = -ENOSYS;
208         }
209         return error;
210 }
211
212 /**
213  *      acpi_suspend_enter - Actually enter a sleep state.
214  *      @pm_state: ignored
215  *
216  *      Flush caches and go to sleep. For STR we have to call arch-specific
217  *      assembly, which in turn call acpi_enter_sleep_state().
218  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
219  */
220 static int acpi_suspend_enter(suspend_state_t pm_state)
221 {
222         acpi_status status = AE_OK;
223         unsigned long flags = 0;
224         u32 acpi_state = acpi_target_sleep_state;
225
226         ACPI_FLUSH_CPU_CACHE();
227
228         /* Do arch specific saving of state. */
229         if (acpi_state == ACPI_STATE_S3) {
230                 int error = acpi_save_state_mem();
231
232                 if (error)
233                         return error;
234         }
235
236         local_irq_save(flags);
237         acpi_enable_wakeup_device(acpi_state);
238         switch (acpi_state) {
239         case ACPI_STATE_S1:
240                 barrier();
241                 status = acpi_enter_sleep_state(acpi_state);
242                 break;
243
244         case ACPI_STATE_S3:
245                 do_suspend_lowlevel();
246                 break;
247         }
248
249         /* If ACPI is not enabled by the BIOS, we need to enable it here. */
250         if (set_sci_en_on_resume)
251                 acpi_set_register(ACPI_BITREG_SCI_ENABLE, 1);
252         else
253                 acpi_enable();
254
255         /* Reprogram control registers and execute _BFS */
256         acpi_leave_sleep_state_prep(acpi_state);
257
258         /* ACPI 3.0 specs (P62) says that it's the responsibility
259          * of the OSPM to clear the status bit [ implying that the
260          * POWER_BUTTON event should not reach userspace ]
261          */
262         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
263                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
264
265         /*
266          * Disable and clear GPE status before interrupt is enabled. Some GPEs
267          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
268          * acpi_leave_sleep_state will reenable specific GPEs later
269          */
270         acpi_disable_all_gpes();
271
272         local_irq_restore(flags);
273         printk(KERN_DEBUG "Back to C!\n");
274
275         /* restore processor state */
276         if (acpi_state == ACPI_STATE_S3)
277                 acpi_restore_state_mem();
278
279         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
280 }
281
282 static int acpi_suspend_state_valid(suspend_state_t pm_state)
283 {
284         u32 acpi_state;
285
286         switch (pm_state) {
287         case PM_SUSPEND_ON:
288         case PM_SUSPEND_STANDBY:
289         case PM_SUSPEND_MEM:
290                 acpi_state = acpi_suspend_states[pm_state];
291
292                 return sleep_states[acpi_state];
293         default:
294                 return 0;
295         }
296 }
297
298 static struct platform_suspend_ops acpi_suspend_ops = {
299         .valid = acpi_suspend_state_valid,
300         .begin = acpi_suspend_begin,
301         .prepare = acpi_pm_prepare,
302         .enter = acpi_suspend_enter,
303         .finish = acpi_pm_finish,
304         .end = acpi_pm_end,
305 };
306
307 /**
308  *      acpi_suspend_begin_old - Set the target system sleep state to the
309  *              state associated with given @pm_state, if supported, and
310  *              execute the _PTS control method.  This function is used if the
311  *              pre-ACPI 2.0 suspend ordering has been requested.
312  */
313 static int acpi_suspend_begin_old(suspend_state_t pm_state)
314 {
315         int error = acpi_suspend_begin(pm_state);
316
317         if (!error)
318                 error = __acpi_pm_prepare();
319         return error;
320 }
321
322 /*
323  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
324  * been requested.
325  */
326 static struct platform_suspend_ops acpi_suspend_ops_old = {
327         .valid = acpi_suspend_state_valid,
328         .begin = acpi_suspend_begin_old,
329         .prepare = acpi_pm_disable_gpes,
330         .enter = acpi_suspend_enter,
331         .finish = acpi_pm_finish,
332         .end = acpi_pm_end,
333         .recover = acpi_pm_finish,
334 };
335
336 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
337 {
338         old_suspend_ordering = true;
339         return 0;
340 }
341
342 static int __init init_set_sci_en_on_resume(const struct dmi_system_id *d)
343 {
344         set_sci_en_on_resume = true;
345         return 0;
346 }
347
348 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
349         {
350         .callback = init_old_suspend_ordering,
351         .ident = "Abit KN9 (nForce4 variant)",
352         .matches = {
353                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
354                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
355                 },
356         },
357         {
358         .callback = init_old_suspend_ordering,
359         .ident = "HP xw4600 Workstation",
360         .matches = {
361                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
362                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
363                 },
364         },
365         {
366         .callback = init_set_sci_en_on_resume,
367         .ident = "Apple MacBook 1,1",
368         .matches = {
369                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
370                 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook1,1"),
371                 },
372         },
373         {
374         .callback = init_set_sci_en_on_resume,
375         .ident = "Apple MacMini 1,1",
376         .matches = {
377                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
378                 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini1,1"),
379                 },
380         },
381         {
382         .callback = init_old_suspend_ordering,
383         .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
384         .matches = {
385                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
386                 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
387                 },
388         },
389         {},
390 };
391 #endif /* CONFIG_SUSPEND */
392
393 #ifdef CONFIG_HIBERNATION
394 /*
395  * The ACPI specification wants us to save NVS memory regions during hibernation
396  * and to restore them during the subsequent resume.  However, it is not certain
397  * if this mechanism is going to work on all machines, so we allow the user to
398  * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
399  * option.
400  */
401 static bool s4_no_nvs;
402
403 void __init acpi_s4_no_nvs(void)
404 {
405         s4_no_nvs = true;
406 }
407
408 static unsigned long s4_hardware_signature;
409 static struct acpi_table_facs *facs;
410 static bool nosigcheck;
411
412 void __init acpi_no_s4_hw_signature(void)
413 {
414         nosigcheck = true;
415 }
416
417 static int acpi_hibernation_begin(void)
418 {
419         int error;
420
421         error = s4_no_nvs ? 0 : hibernate_nvs_alloc();
422         if (!error) {
423                 acpi_target_sleep_state = ACPI_STATE_S4;
424                 acpi_sleep_tts_switch(acpi_target_sleep_state);
425         }
426
427         return error;
428 }
429
430 static int acpi_hibernation_pre_snapshot(void)
431 {
432         int error = acpi_pm_prepare();
433
434         if (!error)
435                 hibernate_nvs_save();
436
437         return error;
438 }
439
440 static int acpi_hibernation_enter(void)
441 {
442         acpi_status status = AE_OK;
443         unsigned long flags = 0;
444
445         ACPI_FLUSH_CPU_CACHE();
446
447         local_irq_save(flags);
448         acpi_enable_wakeup_device(ACPI_STATE_S4);
449         /* This shouldn't return.  If it returns, we have a problem */
450         status = acpi_enter_sleep_state(ACPI_STATE_S4);
451         /* Reprogram control registers and execute _BFS */
452         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
453         local_irq_restore(flags);
454
455         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
456 }
457
458 static void acpi_hibernation_finish(void)
459 {
460         hibernate_nvs_free();
461         acpi_pm_finish();
462 }
463
464 static void acpi_hibernation_leave(void)
465 {
466         /*
467          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
468          * enable it here.
469          */
470         acpi_enable();
471         /* Reprogram control registers and execute _BFS */
472         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
473         /* Check the hardware signature */
474         if (facs && s4_hardware_signature != facs->hardware_signature) {
475                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
476                         "cannot resume!\n");
477                 panic("ACPI S4 hardware signature mismatch");
478         }
479         /* Restore the NVS memory area */
480         hibernate_nvs_restore();
481 }
482
483 static void acpi_pm_enable_gpes(void)
484 {
485         acpi_enable_all_runtime_gpes();
486 }
487
488 static struct platform_hibernation_ops acpi_hibernation_ops = {
489         .begin = acpi_hibernation_begin,
490         .end = acpi_pm_end,
491         .pre_snapshot = acpi_hibernation_pre_snapshot,
492         .finish = acpi_hibernation_finish,
493         .prepare = acpi_pm_prepare,
494         .enter = acpi_hibernation_enter,
495         .leave = acpi_hibernation_leave,
496         .pre_restore = acpi_pm_disable_gpes,
497         .restore_cleanup = acpi_pm_enable_gpes,
498 };
499
500 /**
501  *      acpi_hibernation_begin_old - Set the target system sleep state to
502  *              ACPI_STATE_S4 and execute the _PTS control method.  This
503  *              function is used if the pre-ACPI 2.0 suspend ordering has been
504  *              requested.
505  */
506 static int acpi_hibernation_begin_old(void)
507 {
508         int error;
509         /*
510          * The _TTS object should always be evaluated before the _PTS object.
511          * When the old_suspended_ordering is true, the _PTS object is
512          * evaluated in the acpi_sleep_prepare.
513          */
514         acpi_sleep_tts_switch(ACPI_STATE_S4);
515
516         error = acpi_sleep_prepare(ACPI_STATE_S4);
517
518         if (!error) {
519                 if (!s4_no_nvs)
520                         error = hibernate_nvs_alloc();
521                 if (!error)
522                         acpi_target_sleep_state = ACPI_STATE_S4;
523         }
524         return error;
525 }
526
527 static int acpi_hibernation_pre_snapshot_old(void)
528 {
529         int error = acpi_pm_disable_gpes();
530
531         if (!error)
532                 hibernate_nvs_save();
533
534         return error;
535 }
536
537 /*
538  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
539  * been requested.
540  */
541 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
542         .begin = acpi_hibernation_begin_old,
543         .end = acpi_pm_end,
544         .pre_snapshot = acpi_hibernation_pre_snapshot_old,
545         .finish = acpi_hibernation_finish,
546         .prepare = acpi_pm_disable_gpes,
547         .enter = acpi_hibernation_enter,
548         .leave = acpi_hibernation_leave,
549         .pre_restore = acpi_pm_disable_gpes,
550         .restore_cleanup = acpi_pm_enable_gpes,
551         .recover = acpi_pm_finish,
552 };
553 #endif /* CONFIG_HIBERNATION */
554
555 int acpi_suspend(u32 acpi_state)
556 {
557         suspend_state_t states[] = {
558                 [1] = PM_SUSPEND_STANDBY,
559                 [3] = PM_SUSPEND_MEM,
560                 [5] = PM_SUSPEND_MAX
561         };
562
563         if (acpi_state < 6 && states[acpi_state])
564                 return pm_suspend(states[acpi_state]);
565         if (acpi_state == 4)
566                 return hibernate();
567         return -EINVAL;
568 }
569
570 #ifdef CONFIG_PM_SLEEP
571 /**
572  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
573  *              in the system sleep state given by %acpi_target_sleep_state
574  *      @dev: device to examine; its driver model wakeup flags control
575  *              whether it should be able to wake up the system
576  *      @d_min_p: used to store the upper limit of allowed states range
577  *      Return value: preferred power state of the device on success, -ENODEV on
578  *              failure (ie. if there's no 'struct acpi_device' for @dev)
579  *
580  *      Find the lowest power (highest number) ACPI device power state that
581  *      device @dev can be in while the system is in the sleep state represented
582  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
583  *      able to wake up the system from this sleep state.  If @d_min_p is set,
584  *      the highest power (lowest number) device power state of @dev allowed
585  *      in this system sleep state is stored at the location pointed to by it.
586  *
587  *      The caller must ensure that @dev is valid before using this function.
588  *      The caller is also responsible for figuring out if the device is
589  *      supposed to be able to wake up the system and passing this information
590  *      via @wake.
591  */
592
593 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
594 {
595         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
596         struct acpi_device *adev;
597         char acpi_method[] = "_SxD";
598         unsigned long long d_min, d_max;
599
600         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
601                 printk(KERN_DEBUG "ACPI handle has no context!\n");
602                 return -ENODEV;
603         }
604
605         acpi_method[2] = '0' + acpi_target_sleep_state;
606         /*
607          * If the sleep state is S0, we will return D3, but if the device has
608          * _S0W, we will use the value from _S0W
609          */
610         d_min = ACPI_STATE_D0;
611         d_max = ACPI_STATE_D3;
612
613         /*
614          * If present, _SxD methods return the minimum D-state (highest power
615          * state) we can use for the corresponding S-states.  Otherwise, the
616          * minimum D-state is D0 (ACPI 3.x).
617          *
618          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
619          * provided -- that's our fault recovery, we ignore retval.
620          */
621         if (acpi_target_sleep_state > ACPI_STATE_S0)
622                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
623
624         /*
625          * If _PRW says we can wake up the system from the target sleep state,
626          * the D-state returned by _SxD is sufficient for that (we assume a
627          * wakeup-aware driver if wake is set).  Still, if _SxW exists
628          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
629          * can wake the system.  _S0W may be valid, too.
630          */
631         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
632             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
633              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
634                 acpi_status status;
635
636                 acpi_method[3] = 'W';
637                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
638                                                 &d_max);
639                 if (ACPI_FAILURE(status)) {
640                         d_max = d_min;
641                 } else if (d_max < d_min) {
642                         /* Warn the user of the broken DSDT */
643                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
644                                 acpi_method);
645                         /* Sanitize it */
646                         d_min = d_max;
647                 }
648         }
649
650         if (d_min_p)
651                 *d_min_p = d_min;
652         return d_max;
653 }
654
655 /**
656  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
657  *                                  capability of given device
658  *      @dev: device to handle
659  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
660  */
661 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
662 {
663         acpi_handle handle;
664         struct acpi_device *adev;
665
666         if (!device_may_wakeup(dev))
667                 return -EINVAL;
668
669         handle = DEVICE_ACPI_HANDLE(dev);
670         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
671                 printk(KERN_DEBUG "ACPI handle has no context!\n");
672                 return -ENODEV;
673         }
674
675         return enable ?
676                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
677                 acpi_disable_wakeup_device_power(adev);
678 }
679 #endif
680
681 static void acpi_power_off_prepare(void)
682 {
683         /* Prepare to power off the system */
684         acpi_sleep_prepare(ACPI_STATE_S5);
685         acpi_disable_all_gpes();
686 }
687
688 static void acpi_power_off(void)
689 {
690         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
691         printk(KERN_DEBUG "%s called\n", __func__);
692         local_irq_disable();
693         acpi_enable_wakeup_device(ACPI_STATE_S5);
694         acpi_enter_sleep_state(ACPI_STATE_S5);
695 }
696
697 int __init acpi_sleep_init(void)
698 {
699         acpi_status status;
700         u8 type_a, type_b;
701 #ifdef CONFIG_SUSPEND
702         int i = 0;
703
704         dmi_check_system(acpisleep_dmi_table);
705 #endif
706
707         if (acpi_disabled)
708                 return 0;
709
710         sleep_states[ACPI_STATE_S0] = 1;
711         printk(KERN_INFO PREFIX "(supports S0");
712
713 #ifdef CONFIG_SUSPEND
714         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
715                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
716                 if (ACPI_SUCCESS(status)) {
717                         sleep_states[i] = 1;
718                         printk(" S%d", i);
719                 }
720         }
721
722         suspend_set_ops(old_suspend_ordering ?
723                 &acpi_suspend_ops_old : &acpi_suspend_ops);
724 #endif
725
726 #ifdef CONFIG_HIBERNATION
727         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
728         if (ACPI_SUCCESS(status)) {
729                 hibernation_set_ops(old_suspend_ordering ?
730                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
731                 sleep_states[ACPI_STATE_S4] = 1;
732                 printk(" S4");
733                 if (!nosigcheck) {
734                         acpi_get_table(ACPI_SIG_FACS, 1,
735                                 (struct acpi_table_header **)&facs);
736                         if (facs)
737                                 s4_hardware_signature =
738                                         facs->hardware_signature;
739                 }
740         }
741 #endif
742         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
743         if (ACPI_SUCCESS(status)) {
744                 sleep_states[ACPI_STATE_S5] = 1;
745                 printk(" S5");
746                 pm_power_off_prepare = acpi_power_off_prepare;
747                 pm_power_off = acpi_power_off;
748         }
749         printk(")\n");
750         /*
751          * Register the tts_notifier to reboot notifier list so that the _TTS
752          * object can also be evaluated when the system enters S5.
753          */
754         register_reboot_notifier(&tts_notifier);
755         return 0;
756 }