ACPI: introduce kernel parameter acpi_sleep=sci_force_enable
[linux-3.10.git] / 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
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  * According to the ACPI specification the BIOS should make sure that ACPI is
85  * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states.  Still,
86  * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
87  * on such systems during resume.  Unfortunately that doesn't help in
88  * particularly pathological cases in which SCI_EN has to be set directly on
89  * resume, although the specification states very clearly that this flag is
90  * owned by the hardware.  The set_sci_en_on_resume variable will be set in such
91  * cases.
92  */
93 static bool set_sci_en_on_resume;
94
95 void __init acpi_set_sci_en_on_resume(void)
96 {
97         set_sci_en_on_resume = true;
98 }
99
100 /*
101  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
102  * user to request that behavior by using the 'acpi_old_suspend_ordering'
103  * kernel command line option that causes the following variable to be set.
104  */
105 static bool old_suspend_ordering;
106
107 void __init acpi_old_suspend_ordering(void)
108 {
109         old_suspend_ordering = true;
110 }
111
112 /**
113  *      acpi_pm_disable_gpes - Disable the GPEs.
114  */
115 static int acpi_pm_disable_gpes(void)
116 {
117         acpi_disable_all_gpes();
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         if (error)
132                 acpi_target_sleep_state = ACPI_STATE_S0;
133         return error;
134 }
135
136 /**
137  *      acpi_pm_prepare - Prepare the platform to enter the target sleep
138  *              state and disable the GPEs.
139  */
140 static int acpi_pm_prepare(void)
141 {
142         int error = __acpi_pm_prepare();
143
144         if (!error)
145                 acpi_disable_all_gpes();
146         return error;
147 }
148
149 /**
150  *      acpi_pm_finish - Instruct the platform to leave a sleep state.
151  *
152  *      This is called after we wake back up (or if entering the sleep state
153  *      failed).
154  */
155 static void acpi_pm_finish(void)
156 {
157         u32 acpi_state = acpi_target_sleep_state;
158
159         if (acpi_state == ACPI_STATE_S0)
160                 return;
161
162         printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
163                 acpi_state);
164         acpi_disable_wakeup_device(acpi_state);
165         acpi_leave_sleep_state(acpi_state);
166
167         /* reset firmware waking vector */
168         acpi_set_firmware_waking_vector((acpi_physical_address) 0);
169
170         acpi_target_sleep_state = ACPI_STATE_S0;
171 }
172
173 /**
174  *      acpi_pm_end - Finish up suspend sequence.
175  */
176 static void acpi_pm_end(void)
177 {
178         /*
179          * This is necessary in case acpi_pm_finish() is not called during a
180          * failing transition to a sleep state.
181          */
182         acpi_target_sleep_state = ACPI_STATE_S0;
183         acpi_sleep_tts_switch(acpi_target_sleep_state);
184 }
185 #else /* !CONFIG_ACPI_SLEEP */
186 #define acpi_target_sleep_state ACPI_STATE_S0
187 #endif /* CONFIG_ACPI_SLEEP */
188
189 #ifdef CONFIG_SUSPEND
190 extern void do_suspend_lowlevel(void);
191
192 static u32 acpi_suspend_states[] = {
193         [PM_SUSPEND_ON] = ACPI_STATE_S0,
194         [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
195         [PM_SUSPEND_MEM] = ACPI_STATE_S3,
196         [PM_SUSPEND_MAX] = ACPI_STATE_S5
197 };
198
199 /**
200  *      acpi_suspend_begin - Set the target system sleep state to the state
201  *              associated with given @pm_state, if supported.
202  */
203 static int acpi_suspend_begin(suspend_state_t pm_state)
204 {
205         u32 acpi_state = acpi_suspend_states[pm_state];
206         int error = 0;
207
208         if (sleep_states[acpi_state]) {
209                 acpi_target_sleep_state = acpi_state;
210                 acpi_sleep_tts_switch(acpi_target_sleep_state);
211         } else {
212                 printk(KERN_ERR "ACPI does not support this state: %d\n",
213                         pm_state);
214                 error = -ENOSYS;
215         }
216         return error;
217 }
218
219 /**
220  *      acpi_suspend_enter - Actually enter a sleep state.
221  *      @pm_state: ignored
222  *
223  *      Flush caches and go to sleep. For STR we have to call arch-specific
224  *      assembly, which in turn call acpi_enter_sleep_state().
225  *      It's unfortunate, but it works. Please fix if you're feeling frisky.
226  */
227 static int acpi_suspend_enter(suspend_state_t pm_state)
228 {
229         acpi_status status = AE_OK;
230         unsigned long flags = 0;
231         u32 acpi_state = acpi_target_sleep_state;
232
233         ACPI_FLUSH_CPU_CACHE();
234
235         /* Do arch specific saving of state. */
236         if (acpi_state == ACPI_STATE_S3) {
237                 int error = acpi_save_state_mem();
238
239                 if (error)
240                         return error;
241         }
242
243         local_irq_save(flags);
244         acpi_enable_wakeup_device(acpi_state);
245         switch (acpi_state) {
246         case ACPI_STATE_S1:
247                 barrier();
248                 status = acpi_enter_sleep_state(acpi_state);
249                 break;
250
251         case ACPI_STATE_S3:
252                 do_suspend_lowlevel();
253                 break;
254         }
255
256         /* If ACPI is not enabled by the BIOS, we need to enable it here. */
257         if (set_sci_en_on_resume)
258                 acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
259         else
260                 acpi_enable();
261
262         /* Reprogram control registers and execute _BFS */
263         acpi_leave_sleep_state_prep(acpi_state);
264
265         /* ACPI 3.0 specs (P62) says that it's the responsibility
266          * of the OSPM to clear the status bit [ implying that the
267          * POWER_BUTTON event should not reach userspace ]
268          */
269         if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
270                 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
271
272         /*
273          * Disable and clear GPE status before interrupt is enabled. Some GPEs
274          * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
275          * acpi_leave_sleep_state will reenable specific GPEs later
276          */
277         acpi_disable_all_gpes();
278
279         local_irq_restore(flags);
280         printk(KERN_DEBUG "Back to C!\n");
281
282         /* restore processor state */
283         if (acpi_state == ACPI_STATE_S3)
284                 acpi_restore_state_mem();
285
286         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
287 }
288
289 static int acpi_suspend_state_valid(suspend_state_t pm_state)
290 {
291         u32 acpi_state;
292
293         switch (pm_state) {
294         case PM_SUSPEND_ON:
295         case PM_SUSPEND_STANDBY:
296         case PM_SUSPEND_MEM:
297                 acpi_state = acpi_suspend_states[pm_state];
298
299                 return sleep_states[acpi_state];
300         default:
301                 return 0;
302         }
303 }
304
305 static struct platform_suspend_ops acpi_suspend_ops = {
306         .valid = acpi_suspend_state_valid,
307         .begin = acpi_suspend_begin,
308         .prepare_late = acpi_pm_prepare,
309         .enter = acpi_suspend_enter,
310         .wake = acpi_pm_finish,
311         .end = acpi_pm_end,
312 };
313
314 /**
315  *      acpi_suspend_begin_old - Set the target system sleep state to the
316  *              state associated with given @pm_state, if supported, and
317  *              execute the _PTS control method.  This function is used if the
318  *              pre-ACPI 2.0 suspend ordering has been requested.
319  */
320 static int acpi_suspend_begin_old(suspend_state_t pm_state)
321 {
322         int error = acpi_suspend_begin(pm_state);
323
324         if (!error)
325                 error = __acpi_pm_prepare();
326         return error;
327 }
328
329 /*
330  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
331  * been requested.
332  */
333 static struct platform_suspend_ops acpi_suspend_ops_old = {
334         .valid = acpi_suspend_state_valid,
335         .begin = acpi_suspend_begin_old,
336         .prepare_late = acpi_pm_disable_gpes,
337         .enter = acpi_suspend_enter,
338         .wake = acpi_pm_finish,
339         .end = acpi_pm_end,
340         .recover = acpi_pm_finish,
341 };
342
343 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
344 {
345         old_suspend_ordering = true;
346         return 0;
347 }
348
349 static int __init init_set_sci_en_on_resume(const struct dmi_system_id *d)
350 {
351         set_sci_en_on_resume = true;
352         return 0;
353 }
354
355 static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
356         {
357         .callback = init_old_suspend_ordering,
358         .ident = "Abit KN9 (nForce4 variant)",
359         .matches = {
360                 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
361                 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
362                 },
363         },
364         {
365         .callback = init_old_suspend_ordering,
366         .ident = "HP xw4600 Workstation",
367         .matches = {
368                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
369                 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
370                 },
371         },
372         {
373         .callback = init_set_sci_en_on_resume,
374         .ident = "Apple MacBook 1,1",
375         .matches = {
376                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
377                 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook1,1"),
378                 },
379         },
380         {
381         .callback = init_set_sci_en_on_resume,
382         .ident = "Apple MacMini 1,1",
383         .matches = {
384                 DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
385                 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini1,1"),
386                 },
387         },
388         {
389         .callback = init_old_suspend_ordering,
390         .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
391         .matches = {
392                 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
393                 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
394                 },
395         },
396         {
397         .callback = init_set_sci_en_on_resume,
398         .ident = "Toshiba Satellite L300",
399         .matches = {
400                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
401                 DMI_MATCH(DMI_PRODUCT_NAME, "Satellite L300"),
402                 },
403         },
404         {
405         .callback = init_set_sci_en_on_resume,
406         .ident = "Hewlett-Packard HP G7000 Notebook PC",
407         .matches = {
408                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
409                 DMI_MATCH(DMI_PRODUCT_NAME, "HP G7000 Notebook PC"),
410                 },
411         },
412         {
413         .callback = init_set_sci_en_on_resume,
414         .ident = "Hewlett-Packard HP Pavilion dv3 Notebook PC",
415         .matches = {
416                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
417                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv3 Notebook PC"),
418                 },
419         },
420         {
421         .callback = init_set_sci_en_on_resume,
422         .ident = "Hewlett-Packard Pavilion dv4",
423         .matches = {
424                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
425                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv4"),
426                 },
427         },
428         {
429         .callback = init_set_sci_en_on_resume,
430         .ident = "Hewlett-Packard Pavilion dv7",
431         .matches = {
432                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
433                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv7"),
434                 },
435         },
436         {
437         .callback = init_set_sci_en_on_resume,
438         .ident = "Hewlett-Packard Compaq Presario C700 Notebook PC",
439         .matches = {
440                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
441                 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq Presario C700 Notebook PC"),
442                 },
443         },
444         {
445         .callback = init_set_sci_en_on_resume,
446         .ident = "Hewlett-Packard Compaq Presario CQ40 Notebook PC",
447         .matches = {
448                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
449                 DMI_MATCH(DMI_PRODUCT_NAME, "Compaq Presario CQ40 Notebook PC"),
450                 },
451         },
452         {
453         .callback = init_old_suspend_ordering,
454         .ident = "Panasonic CF51-2L",
455         .matches = {
456                 DMI_MATCH(DMI_BOARD_VENDOR,
457                                 "Matsushita Electric Industrial Co.,Ltd."),
458                 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
459                 },
460         },
461         {},
462 };
463 #endif /* CONFIG_SUSPEND */
464
465 #ifdef CONFIG_HIBERNATION
466 /*
467  * The ACPI specification wants us to save NVS memory regions during hibernation
468  * and to restore them during the subsequent resume.  However, it is not certain
469  * if this mechanism is going to work on all machines, so we allow the user to
470  * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
471  * option.
472  */
473 static bool s4_no_nvs;
474
475 void __init acpi_s4_no_nvs(void)
476 {
477         s4_no_nvs = true;
478 }
479
480 static unsigned long s4_hardware_signature;
481 static struct acpi_table_facs *facs;
482 static bool nosigcheck;
483
484 void __init acpi_no_s4_hw_signature(void)
485 {
486         nosigcheck = true;
487 }
488
489 static int acpi_hibernation_begin(void)
490 {
491         int error;
492
493         error = s4_no_nvs ? 0 : hibernate_nvs_alloc();
494         if (!error) {
495                 acpi_target_sleep_state = ACPI_STATE_S4;
496                 acpi_sleep_tts_switch(acpi_target_sleep_state);
497         }
498
499         return error;
500 }
501
502 static int acpi_hibernation_pre_snapshot(void)
503 {
504         int error = acpi_pm_prepare();
505
506         if (!error)
507                 hibernate_nvs_save();
508
509         return error;
510 }
511
512 static int acpi_hibernation_enter(void)
513 {
514         acpi_status status = AE_OK;
515         unsigned long flags = 0;
516
517         ACPI_FLUSH_CPU_CACHE();
518
519         local_irq_save(flags);
520         acpi_enable_wakeup_device(ACPI_STATE_S4);
521         /* This shouldn't return.  If it returns, we have a problem */
522         status = acpi_enter_sleep_state(ACPI_STATE_S4);
523         /* Reprogram control registers and execute _BFS */
524         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
525         local_irq_restore(flags);
526
527         return ACPI_SUCCESS(status) ? 0 : -EFAULT;
528 }
529
530 static void acpi_hibernation_finish(void)
531 {
532         hibernate_nvs_free();
533         acpi_pm_finish();
534 }
535
536 static void acpi_hibernation_leave(void)
537 {
538         /*
539          * If ACPI is not enabled by the BIOS and the boot kernel, we need to
540          * enable it here.
541          */
542         acpi_enable();
543         /* Reprogram control registers and execute _BFS */
544         acpi_leave_sleep_state_prep(ACPI_STATE_S4);
545         /* Check the hardware signature */
546         if (facs && s4_hardware_signature != facs->hardware_signature) {
547                 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
548                         "cannot resume!\n");
549                 panic("ACPI S4 hardware signature mismatch");
550         }
551         /* Restore the NVS memory area */
552         hibernate_nvs_restore();
553 }
554
555 static void acpi_pm_enable_gpes(void)
556 {
557         acpi_enable_all_runtime_gpes();
558 }
559
560 static struct platform_hibernation_ops acpi_hibernation_ops = {
561         .begin = acpi_hibernation_begin,
562         .end = acpi_pm_end,
563         .pre_snapshot = acpi_hibernation_pre_snapshot,
564         .finish = acpi_hibernation_finish,
565         .prepare = acpi_pm_prepare,
566         .enter = acpi_hibernation_enter,
567         .leave = acpi_hibernation_leave,
568         .pre_restore = acpi_pm_disable_gpes,
569         .restore_cleanup = acpi_pm_enable_gpes,
570 };
571
572 /**
573  *      acpi_hibernation_begin_old - Set the target system sleep state to
574  *              ACPI_STATE_S4 and execute the _PTS control method.  This
575  *              function is used if the pre-ACPI 2.0 suspend ordering has been
576  *              requested.
577  */
578 static int acpi_hibernation_begin_old(void)
579 {
580         int error;
581         /*
582          * The _TTS object should always be evaluated before the _PTS object.
583          * When the old_suspended_ordering is true, the _PTS object is
584          * evaluated in the acpi_sleep_prepare.
585          */
586         acpi_sleep_tts_switch(ACPI_STATE_S4);
587
588         error = acpi_sleep_prepare(ACPI_STATE_S4);
589
590         if (!error) {
591                 if (!s4_no_nvs)
592                         error = hibernate_nvs_alloc();
593                 if (!error)
594                         acpi_target_sleep_state = ACPI_STATE_S4;
595         }
596         return error;
597 }
598
599 static int acpi_hibernation_pre_snapshot_old(void)
600 {
601         int error = acpi_pm_disable_gpes();
602
603         if (!error)
604                 hibernate_nvs_save();
605
606         return error;
607 }
608
609 /*
610  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
611  * been requested.
612  */
613 static struct platform_hibernation_ops acpi_hibernation_ops_old = {
614         .begin = acpi_hibernation_begin_old,
615         .end = acpi_pm_end,
616         .pre_snapshot = acpi_hibernation_pre_snapshot_old,
617         .finish = acpi_hibernation_finish,
618         .prepare = acpi_pm_disable_gpes,
619         .enter = acpi_hibernation_enter,
620         .leave = acpi_hibernation_leave,
621         .pre_restore = acpi_pm_disable_gpes,
622         .restore_cleanup = acpi_pm_enable_gpes,
623         .recover = acpi_pm_finish,
624 };
625 #endif /* CONFIG_HIBERNATION */
626
627 int acpi_suspend(u32 acpi_state)
628 {
629         suspend_state_t states[] = {
630                 [1] = PM_SUSPEND_STANDBY,
631                 [3] = PM_SUSPEND_MEM,
632                 [5] = PM_SUSPEND_MAX
633         };
634
635         if (acpi_state < 6 && states[acpi_state])
636                 return pm_suspend(states[acpi_state]);
637         if (acpi_state == 4)
638                 return hibernate();
639         return -EINVAL;
640 }
641
642 #ifdef CONFIG_PM_SLEEP
643 /**
644  *      acpi_pm_device_sleep_state - return preferred power state of ACPI device
645  *              in the system sleep state given by %acpi_target_sleep_state
646  *      @dev: device to examine; its driver model wakeup flags control
647  *              whether it should be able to wake up the system
648  *      @d_min_p: used to store the upper limit of allowed states range
649  *      Return value: preferred power state of the device on success, -ENODEV on
650  *              failure (ie. if there's no 'struct acpi_device' for @dev)
651  *
652  *      Find the lowest power (highest number) ACPI device power state that
653  *      device @dev can be in while the system is in the sleep state represented
654  *      by %acpi_target_sleep_state.  If @wake is nonzero, the device should be
655  *      able to wake up the system from this sleep state.  If @d_min_p is set,
656  *      the highest power (lowest number) device power state of @dev allowed
657  *      in this system sleep state is stored at the location pointed to by it.
658  *
659  *      The caller must ensure that @dev is valid before using this function.
660  *      The caller is also responsible for figuring out if the device is
661  *      supposed to be able to wake up the system and passing this information
662  *      via @wake.
663  */
664
665 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
666 {
667         acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
668         struct acpi_device *adev;
669         char acpi_method[] = "_SxD";
670         unsigned long long d_min, d_max;
671
672         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
673                 printk(KERN_DEBUG "ACPI handle has no context!\n");
674                 return -ENODEV;
675         }
676
677         acpi_method[2] = '0' + acpi_target_sleep_state;
678         /*
679          * If the sleep state is S0, we will return D3, but if the device has
680          * _S0W, we will use the value from _S0W
681          */
682         d_min = ACPI_STATE_D0;
683         d_max = ACPI_STATE_D3;
684
685         /*
686          * If present, _SxD methods return the minimum D-state (highest power
687          * state) we can use for the corresponding S-states.  Otherwise, the
688          * minimum D-state is D0 (ACPI 3.x).
689          *
690          * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
691          * provided -- that's our fault recovery, we ignore retval.
692          */
693         if (acpi_target_sleep_state > ACPI_STATE_S0)
694                 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
695
696         /*
697          * If _PRW says we can wake up the system from the target sleep state,
698          * the D-state returned by _SxD is sufficient for that (we assume a
699          * wakeup-aware driver if wake is set).  Still, if _SxW exists
700          * (ACPI 3.x), it should return the maximum (lowest power) D-state that
701          * can wake the system.  _S0W may be valid, too.
702          */
703         if (acpi_target_sleep_state == ACPI_STATE_S0 ||
704             (device_may_wakeup(dev) && adev->wakeup.state.enabled &&
705              adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
706                 acpi_status status;
707
708                 acpi_method[3] = 'W';
709                 status = acpi_evaluate_integer(handle, acpi_method, NULL,
710                                                 &d_max);
711                 if (ACPI_FAILURE(status)) {
712                         d_max = d_min;
713                 } else if (d_max < d_min) {
714                         /* Warn the user of the broken DSDT */
715                         printk(KERN_WARNING "ACPI: Wrong value from %s\n",
716                                 acpi_method);
717                         /* Sanitize it */
718                         d_min = d_max;
719                 }
720         }
721
722         if (d_min_p)
723                 *d_min_p = d_min;
724         return d_max;
725 }
726
727 /**
728  *      acpi_pm_device_sleep_wake - enable or disable the system wake-up
729  *                                  capability of given device
730  *      @dev: device to handle
731  *      @enable: 'true' - enable, 'false' - disable the wake-up capability
732  */
733 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
734 {
735         acpi_handle handle;
736         struct acpi_device *adev;
737         int error;
738
739         if (!device_can_wakeup(dev))
740                 return -EINVAL;
741
742         handle = DEVICE_ACPI_HANDLE(dev);
743         if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
744                 dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
745                 return -ENODEV;
746         }
747
748         error = enable ?
749                 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
750                 acpi_disable_wakeup_device_power(adev);
751         if (!error)
752                 dev_info(dev, "wake-up capability %s by ACPI\n",
753                                 enable ? "enabled" : "disabled");
754
755         return error;
756 }
757 #endif
758
759 static void acpi_power_off_prepare(void)
760 {
761         /* Prepare to power off the system */
762         acpi_sleep_prepare(ACPI_STATE_S5);
763         acpi_disable_all_gpes();
764 }
765
766 static void acpi_power_off(void)
767 {
768         /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
769         printk(KERN_DEBUG "%s called\n", __func__);
770         local_irq_disable();
771         acpi_enable_wakeup_device(ACPI_STATE_S5);
772         acpi_enter_sleep_state(ACPI_STATE_S5);
773 }
774
775 /*
776  * ACPI 2.0 created the optional _GTS and _BFS,
777  * but industry adoption has been neither rapid nor broad.
778  *
779  * Linux gets into trouble when it executes poorly validated
780  * paths through the BIOS, so disable _GTS and _BFS by default,
781  * but do speak up and offer the option to enable them.
782  */
783 void __init acpi_gts_bfs_check(void)
784 {
785         acpi_handle dummy;
786
787         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
788         {
789                 printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
790                 printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
791                         "please notify linux-acpi@vger.kernel.org\n");
792         }
793         if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
794         {
795                 printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
796                 printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
797                         "please notify linux-acpi@vger.kernel.org\n");
798         }
799 }
800
801 int __init acpi_sleep_init(void)
802 {
803         acpi_status status;
804         u8 type_a, type_b;
805 #ifdef CONFIG_SUSPEND
806         int i = 0;
807
808         dmi_check_system(acpisleep_dmi_table);
809 #endif
810
811         if (acpi_disabled)
812                 return 0;
813
814         sleep_states[ACPI_STATE_S0] = 1;
815         printk(KERN_INFO PREFIX "(supports S0");
816
817 #ifdef CONFIG_SUSPEND
818         for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
819                 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
820                 if (ACPI_SUCCESS(status)) {
821                         sleep_states[i] = 1;
822                         printk(" S%d", i);
823                 }
824         }
825
826         suspend_set_ops(old_suspend_ordering ?
827                 &acpi_suspend_ops_old : &acpi_suspend_ops);
828 #endif
829
830 #ifdef CONFIG_HIBERNATION
831         status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
832         if (ACPI_SUCCESS(status)) {
833                 hibernation_set_ops(old_suspend_ordering ?
834                         &acpi_hibernation_ops_old : &acpi_hibernation_ops);
835                 sleep_states[ACPI_STATE_S4] = 1;
836                 printk(" S4");
837                 if (!nosigcheck) {
838                         acpi_get_table(ACPI_SIG_FACS, 1,
839                                 (struct acpi_table_header **)&facs);
840                         if (facs)
841                                 s4_hardware_signature =
842                                         facs->hardware_signature;
843                 }
844         }
845 #endif
846         status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
847         if (ACPI_SUCCESS(status)) {
848                 sleep_states[ACPI_STATE_S5] = 1;
849                 printk(" S5");
850                 pm_power_off_prepare = acpi_power_off_prepare;
851                 pm_power_off = acpi_power_off;
852         }
853         printk(")\n");
854         /*
855          * Register the tts_notifier to reboot notifier list so that the _TTS
856          * object can also be evaluated when the system enters S5.
857          */
858         register_reboot_notifier(&tts_notifier);
859         acpi_gts_bfs_check();
860         return 0;
861 }