Merge branch 'fix/hda' into topic/hda
[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  * According to the ACPI specification the BIOS should make sure that ACPI is
95  * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states.  Still,
96  * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
97  * on such systems during resume.  Unfortunately that doesn't help in
98  * particularly pathological cases in which SCI_EN has to be set directly on
99  * resume, although the specification states very clearly that this flag is
100  * owned by the hardware.  The set_sci_en_on_resume variable will be set in such
101  * cases.
102  */
103 static bool set_sci_en_on_resume;
104 /*
105  * The ACPI specification wants us to save NVS memory regions during hibernation
106  * and to restore them during the subsequent resume.  However, it is not certain
107  * if this mechanism is going to work on all machines, so we allow the user to
108  * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
109  * option.
110  */
111 static bool s4_no_nvs;
112
113 void __init acpi_s4_no_nvs(void)
114 {
115         s4_no_nvs = true;
116 }
117
118 /**
119  *      acpi_pm_disable_gpes - Disable the GPEs.
120  */
121 static int acpi_pm_disable_gpes(void)
122 {
123         acpi_disable_all_gpes();
124         return 0;
125 }
126
127 /**
128  *      __acpi_pm_prepare - Prepare the platform to enter the target state.
129  *
130  *      If necessary, set the firmware waking vector and do arch-specific
131  *      nastiness to get the wakeup code to the waking vector.
132  */
133 static int __acpi_pm_prepare(void)
134 {
135         int error = acpi_sleep_prepare(acpi_target_sleep_state);
136
137         if (error)
138                 acpi_target_sleep_state = ACPI_STATE_S0;
139         return error;
140 }
141
142 /**
143  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
144  *              state and disable the GPEs.
145  */
146 static int acpi_pm_prepare(void)
147 {
148         int error = __acpi_pm_prepare();
149
150         if (!error)
151                 acpi_disable_all_gpes();
152         return error;
153 }
154
155 /**
156  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
157  *
158  *      This is called after we wake back up (or if entering the sleep state
159  *      failed).
160  */
161 static void acpi_pm_finish(void)
162 {
163         u32 acpi_state = acpi_target_sleep_state;
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         if (sleep_states[acpi_state]) {
215                 acpi_target_sleep_state = acpi_state;
216                 acpi_sleep_tts_switch(acpi_target_sleep_state);
217         } else {
218                 printk(KERN_ERR "ACPI does not support this state: %d\n",
219                         pm_state);
220                 error = -ENOSYS;
221         }
222         return error;
223 }
224
225 /**
226  *      acpi_suspend_enter - Actually enter a sleep state.
227  *      @pm_state: ignored
228  *
229  *      Flush caches and go to sleep. For STR we have to call arch-specific
230  *      assembly, which in turn call acpi_enter_sleep_state().
231  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
232  */
233 static int acpi_suspend_enter(suspend_state_t pm_state)
234 {
235         acpi_status status = AE_OK;
236         unsigned long flags = 0;
237         u32 acpi_state = acpi_target_sleep_state;
238
239         ACPI_FLUSH_CPU_CACHE();
240
241         /* Do arch specific saving of state. */
242         if (acpi_state == ACPI_STATE_S3) {
243                 int error = acpi_save_state_mem();
244
245                 if (error)
246                         return error;
247         }
248
249         local_irq_save(flags);
250         acpi_enable_wakeup_device(acpi_state);
251         switch (acpi_state) {
252         case ACPI_STATE_S1:
253                 barrier();
254                 status = acpi_enter_sleep_state(acpi_state);
255                 break;
256
257         case ACPI_STATE_S3:
258                 do_suspend_lowlevel();
259                 break;
260         }
261
262         /* If ACPI is not enabled by the BIOS, we need to enable it here. */
263         if (set_sci_en_on_resume)
264                 acpi_set_register(ACPI_BITREG_SCI_ENABLE, 1);
265         else
266                 acpi_enable();
267
268         /* Reprogram control registers and execute _BFS */
269         acpi_leave_sleep_state_prep(acpi_state);
270
271         /* ACPI 3.0 specs (P62) says that it's the responsibility
272          * of the OSPM to clear the status bit [ implying that the
273          * POWER_BUTTON event should not reach userspace ]
274          */
275         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
276                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
277
278         /*
279          * Disable and clear GPE status before interrupt is enabled. Some GPEs
280          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
281          * acpi_leave_sleep_state will reenable specific GPEs later
282          */
283         acpi_disable_all_gpes();
284
285         local_irq_restore(flags);
286         printk(KERN_DEBUG "Back to C!\n");
287
288         /* restore processor state */
289         if (acpi_state == ACPI_STATE_S3)
290                 acpi_restore_state_mem();
291
292         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
293 }
294
295 static int acpi_suspend_state_valid(suspend_state_t pm_state)
296 {
297         u32 acpi_state;
298
299         switch (pm_state) {
300         case PM_SUSPEND_ON:
301         case PM_SUSPEND_STANDBY:
302         case PM_SUSPEND_MEM:
303                 acpi_state = acpi_suspend_states[pm_state];
304
305                 return sleep_states[acpi_state];
306         default:
307                 return 0;
308         }
309 }
310
311 static struct platform_suspend_ops acpi_suspend_ops = {
312         .valid = acpi_suspend_state_valid,
313         .begin = acpi_suspend_begin,
314         .prepare = acpi_pm_prepare,
315         .enter = acpi_suspend_enter,
316         .finish = acpi_pm_finish,
317         .end = acpi_pm_end,
318 };
319
320 /**
321  *      acpi_suspend_begin_old - Set the target system sleep state to the
322  *              state associated with given @pm_state, if supported, and
323  *              execute the _PTS control method.  This function is used if the
324  *              pre-ACPI 2.0 suspend ordering has been requested.
325  */
326 static int acpi_suspend_begin_old(suspend_state_t pm_state)
327 {
328         int error = acpi_suspend_begin(pm_state);
329
330         if (!error)
331                 error = __acpi_pm_prepare();
332         return error;
333 }
334
335 /*
336  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
337  * been requested.
338  */
339 static struct platform_suspend_ops acpi_suspend_ops_old = {
340         .valid = acpi_suspend_state_valid,
341         .begin = acpi_suspend_begin_old,
342         .prepare = acpi_pm_disable_gpes,
343         .enter = acpi_suspend_enter,
344         .finish = acpi_pm_finish,
345         .end = acpi_pm_end,
346         .recover = acpi_pm_finish,
347 };
348
349 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
350 {
351         old_suspend_ordering = true;
352         return 0;
353 }
354
355 static int __init init_set_sci_en_on_resume(const struct dmi_system_id *d)
356 {
357         set_sci_en_on_resume = true;
358         return 0;
359 }
360
361 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
362         {
363         .callback = init_old_suspend_ordering,
364         .ident = "Abit KN9 (nForce4 variant)",
365         .matches = {
366                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
367                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
368                 },
369         },
370         {
371         .callback = init_old_suspend_ordering,
372         .ident = "HP xw4600 Workstation",
373         .matches = {
374                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
375                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
376                 },
377         },
378         {
379         .callback = init_set_sci_en_on_resume,
380         .ident = "Apple MacBook 1,1",
381         .matches = {
382                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
383                 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook1,1"),
384                 },
385         },
386         {
387         .callback = init_set_sci_en_on_resume,
388         .ident = "Apple MacMini 1,1",
389         .matches = {
390                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
391                 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini1,1"),
392                 },
393         },
394         {},
395 };
396 #endif /* CONFIG_SUSPEND */
397
398 #ifdef CONFIG_HIBERNATION
399 static unsigned long s4_hardware_signature;
400 static struct acpi_table_facs *facs;
401 static bool nosigcheck;
402
403 void __init acpi_no_s4_hw_signature(void)
404 {
405         nosigcheck = true;
406 }
407
408 static int acpi_hibernation_begin(void)
409 {
410         int error;
411
412         error = s4_no_nvs ? 0 : hibernate_nvs_alloc();
413         if (!error) {
414                 acpi_target_sleep_state = ACPI_STATE_S4;
415                 acpi_sleep_tts_switch(acpi_target_sleep_state);
416         }
417
418         return error;
419 }
420
421 static int acpi_hibernation_pre_snapshot(void)
422 {
423         int error = acpi_pm_prepare();
424
425         if (!error)
426                 hibernate_nvs_save();
427
428         return error;
429 }
430
431 static int acpi_hibernation_enter(void)
432 {
433         acpi_status status = AE_OK;
434         unsigned long flags = 0;
435
436         ACPI_FLUSH_CPU_CACHE();
437
438         local_irq_save(flags);
439         acpi_enable_wakeup_device(ACPI_STATE_S4);
440         /* This shouldn't return.  If it returns, we have a problem */
441         status = acpi_enter_sleep_state(ACPI_STATE_S4);
442         /* Reprogram control registers and execute _BFS */
443         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
444         local_irq_restore(flags);
445
446         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
447 }
448
449 static void acpi_hibernation_finish(void)
450 {
451         hibernate_nvs_free();
452         acpi_pm_finish();
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         hibernate_nvs_restore();
472 }
473
474 static void acpi_pm_enable_gpes(void)
475 {
476         acpi_enable_all_runtime_gpes();
477 }
478
479 static struct platform_hibernation_ops acpi_hibernation_ops = {
480         .begin = acpi_hibernation_begin,
481         .end = acpi_pm_end,
482         .pre_snapshot = acpi_hibernation_pre_snapshot,
483         .finish = acpi_hibernation_finish,
484         .prepare = acpi_pm_prepare,
485         .enter = acpi_hibernation_enter,
486         .leave = acpi_hibernation_leave,
487         .pre_restore = acpi_pm_disable_gpes,
488         .restore_cleanup = acpi_pm_enable_gpes,
489 };
490
491 /**
492  *      acpi_hibernation_begin_old - Set the target system sleep state to
493  *              ACPI_STATE_S4 and execute the _PTS control method.  This
494  *              function is used if the pre-ACPI 2.0 suspend ordering has been
495  *              requested.
496  */
497 static int acpi_hibernation_begin_old(void)
498 {
499         int error;
500         /*
501          * The _TTS object should always be evaluated before the _PTS object.
502          * When the old_suspended_ordering is true, the _PTS object is
503          * evaluated in the acpi_sleep_prepare.
504          */
505         acpi_sleep_tts_switch(ACPI_STATE_S4);
506
507         error = acpi_sleep_prepare(ACPI_STATE_S4);
508
509         if (!error) {
510                 if (!s4_no_nvs)
511                         error = hibernate_nvs_alloc();
512                 if (!error)
513                         acpi_target_sleep_state = ACPI_STATE_S4;
514         }
515         return error;
516 }
517
518 static int acpi_hibernation_pre_snapshot_old(void)
519 {
520         int error = acpi_pm_disable_gpes();
521
522         if (!error)
523                 hibernate_nvs_save();
524
525         return error;
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         .finish = acpi_hibernation_finish,
537         .prepare = acpi_pm_disable_gpes,
538         .enter = acpi_hibernation_enter,
539         .leave = acpi_hibernation_leave,
540         .pre_restore = acpi_pm_disable_gpes,
541         .restore_cleanup = acpi_pm_enable_gpes,
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
657         if (!device_may_wakeup(dev))
658                 return -EINVAL;
659
660         handle = DEVICE_ACPI_HANDLE(dev);
661         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
662                 printk(KERN_DEBUG "ACPI handle has no context!\n");
663                 return -ENODEV;
664         }
665
666         return enable ?
667                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
668                 acpi_disable_wakeup_device_power(adev);
669 }
670 #endif
671
672 static void acpi_power_off_prepare(void)
673 {
674         /* Prepare to power off the system */
675         acpi_sleep_prepare(ACPI_STATE_S5);
676         acpi_disable_all_gpes();
677 }
678
679 static void acpi_power_off(void)
680 {
681         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
682         printk("%s called\n", __func__);
683         local_irq_disable();
684         acpi_enable_wakeup_device(ACPI_STATE_S5);
685         acpi_enter_sleep_state(ACPI_STATE_S5);
686 }
687
688 int __init acpi_sleep_init(void)
689 {
690         acpi_status status;
691         u8 type_a, type_b;
692 #ifdef CONFIG_SUSPEND
693         int i = 0;
694
695         dmi_check_system(acpisleep_dmi_table);
696 #endif
697
698         if (acpi_disabled)
699                 return 0;
700
701         sleep_states[ACPI_STATE_S0] = 1;
702         printk(KERN_INFO PREFIX "(supports S0");
703
704 #ifdef CONFIG_SUSPEND
705         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
706                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
707                 if (ACPI_SUCCESS(status)) {
708                         sleep_states[i] = 1;
709                         printk(" S%d", i);
710                 }
711         }
712
713         suspend_set_ops(old_suspend_ordering ?
714                 &acpi_suspend_ops_old : &acpi_suspend_ops);
715 #endif
716
717 #ifdef CONFIG_HIBERNATION
718         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
719         if (ACPI_SUCCESS(status)) {
720                 hibernation_set_ops(old_suspend_ordering ?
721                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
722                 sleep_states[ACPI_STATE_S4] = 1;
723                 printk(" S4");
724                 if (!nosigcheck) {
725                         acpi_get_table(ACPI_SIG_FACS, 1,
726                                 (struct acpi_table_header **)&facs);
727                         if (facs)
728                                 s4_hardware_signature =
729                                         facs->hardware_signature;
730                 }
731         }
732 #endif
733         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
734         if (ACPI_SUCCESS(status)) {
735                 sleep_states[ACPI_STATE_S5] = 1;
736                 printk(" S5");
737                 pm_power_off_prepare = acpi_power_off_prepare;
738                 pm_power_off = acpi_power_off;
739         }
740         printk(")\n");
741         /*
742          * Register the tts_notifier to reboot notifier list so that the _TTS
743          * object can also be evaluated when the system enters S5.
744          */
745         register_reboot_notifier(&tts_notifier);
746         return 0;
747 }