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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#include <linux/acpi.h>
20
21#include <asm/io.h>
22
23#include <acpi/acpi_bus.h>
24#include <acpi/acpi_drivers.h>
25
26#include "internal.h"
27#include "sleep.h"
28
29static u8 sleep_states[ACPI_S_STATE_COUNT];
30
31static void acpi_sleep_tts_switch(u32 acpi_state)
32{
33 union acpi_object in_arg = { ACPI_TYPE_INTEGER };
34 struct acpi_object_list arg_list = { 1, &in_arg };
35 acpi_status status = AE_OK;
36
37 in_arg.integer.value = acpi_state;
38 status = acpi_evaluate_object(NULL, "\\_TTS", &arg_list, NULL);
39 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
40 /*
41 * OS can't evaluate the _TTS object correctly. Some warning
42 * message will be printed. But it won't break anything.
43 */
44 printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
45 }
46}
47
48static int tts_notify_reboot(struct notifier_block *this,
49 unsigned long code, void *x)
50{
51 acpi_sleep_tts_switch(ACPI_STATE_S5);
52 return NOTIFY_DONE;
53}
54
55static struct notifier_block tts_notifier = {
56 .notifier_call = tts_notify_reboot,
57 .next = NULL,
58 .priority = 0,
59};
60
61static int acpi_sleep_prepare(u32 acpi_state)
62{
63#ifdef CONFIG_ACPI_SLEEP
64 /* do we have a wakeup address for S2 and S3? */
65 if (acpi_state == ACPI_STATE_S3) {
66 if (!acpi_wakeup_address) {
67 return -EFAULT;
68 }
69 acpi_set_firmware_waking_vector(
70 (acpi_physical_address)acpi_wakeup_address);
71
72 }
73 ACPI_FLUSH_CPU_CACHE();
74#endif
75 printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
76 acpi_state);
77 acpi_enable_wakeup_devices(acpi_state);
78 acpi_enter_sleep_state_prep(acpi_state);
79 return 0;
80}
81
82#ifdef CONFIG_ACPI_SLEEP
83static u32 acpi_target_sleep_state = ACPI_STATE_S0;
84
85/*
86 * The ACPI specification wants us to save NVS memory regions during hibernation
87 * and to restore them during the subsequent resume. Windows does that also for
88 * suspend to RAM. However, it is known that this mechanism does not work on
89 * all machines, so we allow the user to disable it with the help of the
90 * 'acpi_sleep=nonvs' kernel command line option.
91 */
92static bool nvs_nosave;
93
94void __init acpi_nvs_nosave(void)
95{
96 nvs_nosave = true;
97}
98
99/*
100 * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
101 * user to request that behavior by using the 'acpi_old_suspend_ordering'
102 * kernel command line option that causes the following variable to be set.
103 */
104static bool old_suspend_ordering;
105
106void __init acpi_old_suspend_ordering(void)
107{
108 old_suspend_ordering = true;
109}
110
111/**
112 * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
113 */
114static int acpi_pm_freeze(void)
115{
116 acpi_disable_all_gpes();
117 acpi_os_wait_events_complete(NULL);
118 acpi_ec_block_transactions();
119 return 0;
120}
121
122/**
123 * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
124 */
125static int acpi_pm_pre_suspend(void)
126{
127 acpi_pm_freeze();
128 return suspend_nvs_save();
129}
130
131/**
132 * __acpi_pm_prepare - Prepare the platform to enter the target state.
133 *
134 * If necessary, set the firmware waking vector and do arch-specific
135 * nastiness to get the wakeup code to the waking vector.
136 */
137static int __acpi_pm_prepare(void)
138{
139 int error = acpi_sleep_prepare(acpi_target_sleep_state);
140 if (error)
141 acpi_target_sleep_state = ACPI_STATE_S0;
142
143 return error;
144}
145
146/**
147 * acpi_pm_prepare - Prepare the platform to enter the target sleep
148 * state and disable the GPEs.
149 */
150static int acpi_pm_prepare(void)
151{
152 int error = __acpi_pm_prepare();
153 if (!error)
154 error = acpi_pm_pre_suspend();
155
156 return error;
157}
158
159/**
160 * acpi_pm_finish - Instruct the platform to leave a sleep state.
161 *
162 * This is called after we wake back up (or if entering the sleep state
163 * failed).
164 */
165static void acpi_pm_finish(void)
166{
167 u32 acpi_state = acpi_target_sleep_state;
168
169 acpi_ec_unblock_transactions();
170 suspend_nvs_free();
171
172 if (acpi_state == ACPI_STATE_S0)
173 return;
174
175 printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
176 acpi_state);
177 acpi_disable_wakeup_devices(acpi_state);
178 acpi_leave_sleep_state(acpi_state);
179
180 /* reset firmware waking vector */
181 acpi_set_firmware_waking_vector((acpi_physical_address) 0);
182
183 acpi_target_sleep_state = ACPI_STATE_S0;
184}
185
186/**
187 * acpi_pm_end - Finish up suspend sequence.
188 */
189static void acpi_pm_end(void)
190{
191 /*
192 * This is necessary in case acpi_pm_finish() is not called during a
193 * failing transition to a sleep state.
194 */
195 acpi_target_sleep_state = ACPI_STATE_S0;
196 acpi_sleep_tts_switch(acpi_target_sleep_state);
197}
198#else /* !CONFIG_ACPI_SLEEP */
199#define acpi_target_sleep_state ACPI_STATE_S0
200#endif /* CONFIG_ACPI_SLEEP */
201
202#ifdef CONFIG_SUSPEND
203static u32 acpi_suspend_states[] = {
204 [PM_SUSPEND_ON] = ACPI_STATE_S0,
205 [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
206 [PM_SUSPEND_MEM] = ACPI_STATE_S3,
207 [PM_SUSPEND_MAX] = ACPI_STATE_S5
208};
209
210/**
211 * acpi_suspend_begin - Set the target system sleep state to the state
212 * associated with given @pm_state, if supported.
213 */
214static int acpi_suspend_begin(suspend_state_t pm_state)
215{
216 u32 acpi_state = acpi_suspend_states[pm_state];
217 int error = 0;
218
219 error = nvs_nosave ? 0 : suspend_nvs_alloc();
220 if (error)
221 return error;
222
223 if (sleep_states[acpi_state]) {
224 acpi_target_sleep_state = acpi_state;
225 acpi_sleep_tts_switch(acpi_target_sleep_state);
226 } else {
227 printk(KERN_ERR "ACPI does not support this state: %d\n",
228 pm_state);
229 error = -ENOSYS;
230 }
231 return error;
232}
233
234/**
235 * acpi_suspend_enter - Actually enter a sleep state.
236 * @pm_state: ignored
237 *
238 * Flush caches and go to sleep. For STR we have to call arch-specific
239 * assembly, which in turn call acpi_enter_sleep_state().
240 * It's unfortunate, but it works. Please fix if you're feeling frisky.
241 */
242static int acpi_suspend_enter(suspend_state_t pm_state)
243{
244 acpi_status status = AE_OK;
245 u32 acpi_state = acpi_target_sleep_state;
246 int error;
247
248 ACPI_FLUSH_CPU_CACHE();
249
250 switch (acpi_state) {
251 case ACPI_STATE_S1:
252 barrier();
253 status = acpi_enter_sleep_state(acpi_state);
254 break;
255
256 case ACPI_STATE_S3:
257 error = acpi_suspend_lowlevel();
258 if (error)
259 return error;
260 pr_info(PREFIX "Low-level resume complete\n");
261 break;
262 }
263
264 /* This violates the spec but is required for bug compatibility. */
265 acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
266
267 /* Reprogram control registers and execute _BFS */
268 acpi_leave_sleep_state_prep(acpi_state);
269
270 /* ACPI 3.0 specs (P62) says that it's the responsibility
271 * of the OSPM to clear the status bit [ implying that the
272 * POWER_BUTTON event should not reach userspace ]
273 */
274 if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3))
275 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
276
277 /*
278 * Disable and clear GPE status before interrupt is enabled. Some GPEs
279 * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
280 * acpi_leave_sleep_state will reenable specific GPEs later
281 */
282 acpi_disable_all_gpes();
283 /* Allow EC transactions to happen. */
284 acpi_ec_unblock_transactions_early();
285
286 suspend_nvs_restore();
287
288 return ACPI_SUCCESS(status) ? 0 : -EFAULT;
289}
290
291static int acpi_suspend_state_valid(suspend_state_t pm_state)
292{
293 u32 acpi_state;
294
295 switch (pm_state) {
296 case PM_SUSPEND_ON:
297 case PM_SUSPEND_STANDBY:
298 case PM_SUSPEND_MEM:
299 acpi_state = acpi_suspend_states[pm_state];
300
301 return sleep_states[acpi_state];
302 default:
303 return 0;
304 }
305}
306
307static const struct platform_suspend_ops acpi_suspend_ops = {
308 .valid = acpi_suspend_state_valid,
309 .begin = acpi_suspend_begin,
310 .prepare_late = acpi_pm_prepare,
311 .enter = acpi_suspend_enter,
312 .wake = acpi_pm_finish,
313 .end = acpi_pm_end,
314};
315
316/**
317 * acpi_suspend_begin_old - Set the target system sleep state to the
318 * state associated with given @pm_state, if supported, and
319 * execute the _PTS control method. This function is used if the
320 * pre-ACPI 2.0 suspend ordering has been requested.
321 */
322static int acpi_suspend_begin_old(suspend_state_t pm_state)
323{
324 int error = acpi_suspend_begin(pm_state);
325 if (!error)
326 error = __acpi_pm_prepare();
327
328 return error;
329}
330
331/*
332 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
333 * been requested.
334 */
335static const struct platform_suspend_ops acpi_suspend_ops_old = {
336 .valid = acpi_suspend_state_valid,
337 .begin = acpi_suspend_begin_old,
338 .prepare_late = acpi_pm_pre_suspend,
339 .enter = acpi_suspend_enter,
340 .wake = acpi_pm_finish,
341 .end = acpi_pm_end,
342 .recover = acpi_pm_finish,
343};
344
345static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
346{
347 old_suspend_ordering = true;
348 return 0;
349}
350
351static int __init init_nvs_nosave(const struct dmi_system_id *d)
352{
353 acpi_nvs_nosave();
354 return 0;
355}
356
357static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
358 {
359 .callback = init_old_suspend_ordering,
360 .ident = "Abit KN9 (nForce4 variant)",
361 .matches = {
362 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
363 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
364 },
365 },
366 {
367 .callback = init_old_suspend_ordering,
368 .ident = "HP xw4600 Workstation",
369 .matches = {
370 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
371 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
372 },
373 },
374 {
375 .callback = init_old_suspend_ordering,
376 .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
377 .matches = {
378 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
379 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
380 },
381 },
382 {
383 .callback = init_old_suspend_ordering,
384 .ident = "Panasonic CF51-2L",
385 .matches = {
386 DMI_MATCH(DMI_BOARD_VENDOR,
387 "Matsushita Electric Industrial Co.,Ltd."),
388 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
389 },
390 },
391 {
392 .callback = init_nvs_nosave,
393 .ident = "Sony Vaio VGN-SR11M",
394 .matches = {
395 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
396 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
397 },
398 },
399 {
400 .callback = init_nvs_nosave,
401 .ident = "Everex StepNote Series",
402 .matches = {
403 DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
404 DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
405 },
406 },
407 {
408 .callback = init_nvs_nosave,
409 .ident = "Sony Vaio VPCEB1Z1E",
410 .matches = {
411 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
412 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
413 },
414 },
415 {
416 .callback = init_nvs_nosave,
417 .ident = "Sony Vaio VGN-NW130D",
418 .matches = {
419 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
420 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
421 },
422 },
423 {
424 .callback = init_nvs_nosave,
425 .ident = "Averatec AV1020-ED2",
426 .matches = {
427 DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
428 DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
429 },
430 },
431 {
432 .callback = init_old_suspend_ordering,
433 .ident = "Asus A8N-SLI DELUXE",
434 .matches = {
435 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
436 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI DELUXE"),
437 },
438 },
439 {
440 .callback = init_old_suspend_ordering,
441 .ident = "Asus A8N-SLI Premium",
442 .matches = {
443 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
444 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI Premium"),
445 },
446 },
447 {},
448};
449#endif /* CONFIG_SUSPEND */
450
451#ifdef CONFIG_HIBERNATION
452static unsigned long s4_hardware_signature;
453static struct acpi_table_facs *facs;
454static bool nosigcheck;
455
456void __init acpi_no_s4_hw_signature(void)
457{
458 nosigcheck = true;
459}
460
461static int acpi_hibernation_begin(void)
462{
463 int error;
464
465 error = nvs_nosave ? 0 : suspend_nvs_alloc();
466 if (!error) {
467 acpi_target_sleep_state = ACPI_STATE_S4;
468 acpi_sleep_tts_switch(acpi_target_sleep_state);
469 }
470
471 return error;
472}
473
474static int acpi_hibernation_enter(void)
475{
476 acpi_status status = AE_OK;
477
478 ACPI_FLUSH_CPU_CACHE();
479
480 /* This shouldn't return. If it returns, we have a problem */
481 status = acpi_enter_sleep_state(ACPI_STATE_S4);
482 /* Reprogram control registers and execute _BFS */
483 acpi_leave_sleep_state_prep(ACPI_STATE_S4);
484
485 return ACPI_SUCCESS(status) ? 0 : -EFAULT;
486}
487
488static void acpi_hibernation_leave(void)
489{
490 /*
491 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
492 * enable it here.
493 */
494 acpi_enable();
495 /* Reprogram control registers and execute _BFS */
496 acpi_leave_sleep_state_prep(ACPI_STATE_S4);
497 /* Check the hardware signature */
498 if (facs && s4_hardware_signature != facs->hardware_signature) {
499 printk(KERN_EMERG "ACPI: Hardware changed while hibernated, "
500 "cannot resume!\n");
501 panic("ACPI S4 hardware signature mismatch");
502 }
503 /* Restore the NVS memory area */
504 suspend_nvs_restore();
505 /* Allow EC transactions to happen. */
506 acpi_ec_unblock_transactions_early();
507}
508
509static void acpi_pm_thaw(void)
510{
511 acpi_ec_unblock_transactions();
512 acpi_enable_all_runtime_gpes();
513}
514
515static const struct platform_hibernation_ops acpi_hibernation_ops = {
516 .begin = acpi_hibernation_begin,
517 .end = acpi_pm_end,
518 .pre_snapshot = acpi_pm_prepare,
519 .finish = acpi_pm_finish,
520 .prepare = acpi_pm_prepare,
521 .enter = acpi_hibernation_enter,
522 .leave = acpi_hibernation_leave,
523 .pre_restore = acpi_pm_freeze,
524 .restore_cleanup = acpi_pm_thaw,
525};
526
527/**
528 * acpi_hibernation_begin_old - Set the target system sleep state to
529 * ACPI_STATE_S4 and execute the _PTS control method. This
530 * function is used if the pre-ACPI 2.0 suspend ordering has been
531 * requested.
532 */
533static int acpi_hibernation_begin_old(void)
534{
535 int error;
536 /*
537 * The _TTS object should always be evaluated before the _PTS object.
538 * When the old_suspended_ordering is true, the _PTS object is
539 * evaluated in the acpi_sleep_prepare.
540 */
541 acpi_sleep_tts_switch(ACPI_STATE_S4);
542
543 error = acpi_sleep_prepare(ACPI_STATE_S4);
544
545 if (!error) {
546 if (!nvs_nosave)
547 error = suspend_nvs_alloc();
548 if (!error)
549 acpi_target_sleep_state = ACPI_STATE_S4;
550 }
551 return error;
552}
553
554/*
555 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
556 * been requested.
557 */
558static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
559 .begin = acpi_hibernation_begin_old,
560 .end = acpi_pm_end,
561 .pre_snapshot = acpi_pm_pre_suspend,
562 .prepare = acpi_pm_freeze,
563 .finish = acpi_pm_finish,
564 .enter = acpi_hibernation_enter,
565 .leave = acpi_hibernation_leave,
566 .pre_restore = acpi_pm_freeze,
567 .restore_cleanup = acpi_pm_thaw,
568 .recover = acpi_pm_finish,
569};
570#endif /* CONFIG_HIBERNATION */
571
572int acpi_suspend(u32 acpi_state)
573{
574 suspend_state_t states[] = {
575 [1] = PM_SUSPEND_STANDBY,
576 [3] = PM_SUSPEND_MEM,
577 [5] = PM_SUSPEND_MAX
578 };
579
580 if (acpi_state < 6 && states[acpi_state])
581 return pm_suspend(states[acpi_state]);
582 if (acpi_state == 4)
583 return hibernate();
584 return -EINVAL;
585}
586
587#ifdef CONFIG_PM
588/**
589 * acpi_pm_device_sleep_state - return preferred power state of ACPI device
590 * in the system sleep state given by %acpi_target_sleep_state
591 * @dev: device to examine; its driver model wakeup flags control
592 * whether it should be able to wake up the system
593 * @d_min_p: used to store the upper limit of allowed states range
594 * Return value: preferred power state of the device on success, -ENODEV on
595 * failure (ie. if there's no 'struct acpi_device' for @dev)
596 *
597 * Find the lowest power (highest number) ACPI device power state that
598 * device @dev can be in while the system is in the sleep state represented
599 * by %acpi_target_sleep_state. If @wake is nonzero, the device should be
600 * able to wake up the system from this sleep state. If @d_min_p is set,
601 * the highest power (lowest number) device power state of @dev allowed
602 * in this system sleep state is stored at the location pointed to by it.
603 *
604 * The caller must ensure that @dev is valid before using this function.
605 * The caller is also responsible for figuring out if the device is
606 * supposed to be able to wake up the system and passing this information
607 * via @wake.
608 */
609
610int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p)
611{
612 acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
613 struct acpi_device *adev;
614 char acpi_method[] = "_SxD";
615 unsigned long long d_min, d_max;
616
617 if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
618 printk(KERN_DEBUG "ACPI handle has no context!\n");
619 return -ENODEV;
620 }
621
622 acpi_method[2] = '0' + acpi_target_sleep_state;
623 /*
624 * If the sleep state is S0, we will return D3, but if the device has
625 * _S0W, we will use the value from _S0W
626 */
627 d_min = ACPI_STATE_D0;
628 d_max = ACPI_STATE_D3;
629
630 /*
631 * If present, _SxD methods return the minimum D-state (highest power
632 * state) we can use for the corresponding S-states. Otherwise, the
633 * minimum D-state is D0 (ACPI 3.x).
634 *
635 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
636 * provided -- that's our fault recovery, we ignore retval.
637 */
638 if (acpi_target_sleep_state > ACPI_STATE_S0)
639 acpi_evaluate_integer(handle, acpi_method, NULL, &d_min);
640
641 /*
642 * If _PRW says we can wake up the system from the target sleep state,
643 * the D-state returned by _SxD is sufficient for that (we assume a
644 * wakeup-aware driver if wake is set). Still, if _SxW exists
645 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
646 * can wake the system. _S0W may be valid, too.
647 */
648 if (acpi_target_sleep_state == ACPI_STATE_S0 ||
649 (device_may_wakeup(dev) &&
650 adev->wakeup.sleep_state <= acpi_target_sleep_state)) {
651 acpi_status status;
652
653 acpi_method[3] = 'W';
654 status = acpi_evaluate_integer(handle, acpi_method, NULL,
655 &d_max);
656 if (ACPI_FAILURE(status)) {
657 if (acpi_target_sleep_state != ACPI_STATE_S0 ||
658 status != AE_NOT_FOUND)
659 d_max = d_min;
660 } else if (d_max < d_min) {
661 /* Warn the user of the broken DSDT */
662 printk(KERN_WARNING "ACPI: Wrong value from %s\n",
663 acpi_method);
664 /* Sanitize it */
665 d_min = d_max;
666 }
667 }
668
669 if (d_min_p)
670 *d_min_p = d_min;
671 return d_max;
672}
673#endif /* CONFIG_PM */
674
675#ifdef CONFIG_PM_SLEEP
676/**
677 * acpi_pm_device_sleep_wake - enable or disable the system wake-up
678 * capability of given device
679 * @dev: device to handle
680 * @enable: 'true' - enable, 'false' - disable the wake-up capability
681 */
682int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
683{
684 acpi_handle handle;
685 struct acpi_device *adev;
686 int error;
687
688 if (!device_can_wakeup(dev))
689 return -EINVAL;
690
691 handle = DEVICE_ACPI_HANDLE(dev);
692 if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
693 dev_dbg(dev, "ACPI handle has no context in %s!\n", __func__);
694 return -ENODEV;
695 }
696
697 error = enable ?
698 acpi_enable_wakeup_device_power(adev, acpi_target_sleep_state) :
699 acpi_disable_wakeup_device_power(adev);
700 if (!error)
701 dev_info(dev, "wake-up capability %s by ACPI\n",
702 enable ? "enabled" : "disabled");
703
704 return error;
705}
706#endif /* CONFIG_PM_SLEEP */
707
708static void acpi_power_off_prepare(void)
709{
710 /* Prepare to power off the system */
711 acpi_sleep_prepare(ACPI_STATE_S5);
712 acpi_disable_all_gpes();
713}
714
715static void acpi_power_off(void)
716{
717 /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
718 printk(KERN_DEBUG "%s called\n", __func__);
719 local_irq_disable();
720 acpi_enter_sleep_state(ACPI_STATE_S5);
721}
722
723/*
724 * ACPI 2.0 created the optional _GTS and _BFS,
725 * but industry adoption has been neither rapid nor broad.
726 *
727 * Linux gets into trouble when it executes poorly validated
728 * paths through the BIOS, so disable _GTS and _BFS by default,
729 * but do speak up and offer the option to enable them.
730 */
731static void __init acpi_gts_bfs_check(void)
732{
733 acpi_handle dummy;
734
735 if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy)))
736 {
737 printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n");
738 printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, "
739 "please notify linux-acpi@vger.kernel.org\n");
740 }
741 if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy)))
742 {
743 printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n");
744 printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, "
745 "please notify linux-acpi@vger.kernel.org\n");
746 }
747}
748
749int __init acpi_sleep_init(void)
750{
751 acpi_status status;
752 u8 type_a, type_b;
753#ifdef CONFIG_SUSPEND
754 int i = 0;
755
756 dmi_check_system(acpisleep_dmi_table);
757#endif
758
759 if (acpi_disabled)
760 return 0;
761
762 sleep_states[ACPI_STATE_S0] = 1;
763 printk(KERN_INFO PREFIX "(supports S0");
764
765#ifdef CONFIG_SUSPEND
766 for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++) {
767 status = acpi_get_sleep_type_data(i, &type_a, &type_b);
768 if (ACPI_SUCCESS(status)) {
769 sleep_states[i] = 1;
770 printk(" S%d", i);
771 }
772 }
773
774 suspend_set_ops(old_suspend_ordering ?
775 &acpi_suspend_ops_old : &acpi_suspend_ops);
776#endif
777
778#ifdef CONFIG_HIBERNATION
779 status = acpi_get_sleep_type_data(ACPI_STATE_S4, &type_a, &type_b);
780 if (ACPI_SUCCESS(status)) {
781 hibernation_set_ops(old_suspend_ordering ?
782 &acpi_hibernation_ops_old : &acpi_hibernation_ops);
783 sleep_states[ACPI_STATE_S4] = 1;
784 printk(" S4");
785 if (!nosigcheck) {
786 acpi_get_table(ACPI_SIG_FACS, 1,
787 (struct acpi_table_header **)&facs);
788 if (facs)
789 s4_hardware_signature =
790 facs->hardware_signature;
791 }
792 }
793#endif
794 status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b);
795 if (ACPI_SUCCESS(status)) {
796 sleep_states[ACPI_STATE_S5] = 1;
797 printk(" S5");
798 pm_power_off_prepare = acpi_power_off_prepare;
799 pm_power_off = acpi_power_off;
800 }
801 printk(")\n");
802 /*
803 * Register the tts_notifier to reboot notifier list so that the _TTS
804 * object can also be evaluated when the system enters S5.
805 */
806 register_reboot_notifier(&tts_notifier);
807 acpi_gts_bfs_check();
808 return 0;
809}
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/interrupt.h>
18#include <linux/suspend.h>
19#include <linux/reboot.h>
20#include <linux/acpi.h>
21#include <linux/module.h>
22#include <linux/syscore_ops.h>
23#include <asm/io.h>
24#include <trace/events/power.h>
25
26#include "internal.h"
27#include "sleep.h"
28
29/*
30 * Some HW-full platforms do not have _S5, so they may need
31 * to leverage efi power off for a shutdown.
32 */
33bool acpi_no_s5;
34static u8 sleep_states[ACPI_S_STATE_COUNT];
35
36static void acpi_sleep_tts_switch(u32 acpi_state)
37{
38 acpi_status status;
39
40 status = acpi_execute_simple_method(NULL, "\\_TTS", acpi_state);
41 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
42 /*
43 * OS can't evaluate the _TTS object correctly. Some warning
44 * message will be printed. But it won't break anything.
45 */
46 printk(KERN_NOTICE "Failure in evaluating _TTS object\n");
47 }
48}
49
50static int tts_notify_reboot(struct notifier_block *this,
51 unsigned long code, void *x)
52{
53 acpi_sleep_tts_switch(ACPI_STATE_S5);
54 return NOTIFY_DONE;
55}
56
57static struct notifier_block tts_notifier = {
58 .notifier_call = tts_notify_reboot,
59 .next = NULL,
60 .priority = 0,
61};
62
63static int acpi_sleep_prepare(u32 acpi_state)
64{
65#ifdef CONFIG_ACPI_SLEEP
66 /* do we have a wakeup address for S2 and S3? */
67 if (acpi_state == ACPI_STATE_S3) {
68 if (!acpi_wakeup_address)
69 return -EFAULT;
70 acpi_set_waking_vector(acpi_wakeup_address);
71
72 }
73 ACPI_FLUSH_CPU_CACHE();
74#endif
75 printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
76 acpi_state);
77 acpi_enable_wakeup_devices(acpi_state);
78 acpi_enter_sleep_state_prep(acpi_state);
79 return 0;
80}
81
82static bool acpi_sleep_state_supported(u8 sleep_state)
83{
84 acpi_status status;
85 u8 type_a, type_b;
86
87 status = acpi_get_sleep_type_data(sleep_state, &type_a, &type_b);
88 return ACPI_SUCCESS(status) && (!acpi_gbl_reduced_hardware
89 || (acpi_gbl_FADT.sleep_control.address
90 && acpi_gbl_FADT.sleep_status.address));
91}
92
93#ifdef CONFIG_ACPI_SLEEP
94static u32 acpi_target_sleep_state = ACPI_STATE_S0;
95
96u32 acpi_target_system_state(void)
97{
98 return acpi_target_sleep_state;
99}
100EXPORT_SYMBOL_GPL(acpi_target_system_state);
101
102static bool pwr_btn_event_pending;
103
104/*
105 * The ACPI specification wants us to save NVS memory regions during hibernation
106 * and to restore them during the subsequent resume. Windows does that also for
107 * suspend to RAM. However, it is known that this mechanism does not work on
108 * all machines, so we allow the user to disable it with the help of the
109 * 'acpi_sleep=nonvs' kernel command line option.
110 */
111static bool nvs_nosave;
112
113void __init acpi_nvs_nosave(void)
114{
115 nvs_nosave = true;
116}
117
118/*
119 * The ACPI specification wants us to save NVS memory regions during hibernation
120 * but says nothing about saving NVS during S3. Not all versions of Windows
121 * save NVS on S3 suspend either, and it is clear that not all systems need
122 * NVS to be saved at S3 time. To improve suspend/resume time, allow the
123 * user to disable saving NVS on S3 if their system does not require it, but
124 * continue to save/restore NVS for S4 as specified.
125 */
126static bool nvs_nosave_s3;
127
128void __init acpi_nvs_nosave_s3(void)
129{
130 nvs_nosave_s3 = true;
131}
132
133static int __init init_nvs_save_s3(const struct dmi_system_id *d)
134{
135 nvs_nosave_s3 = false;
136 return 0;
137}
138
139/*
140 * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
141 * user to request that behavior by using the 'acpi_old_suspend_ordering'
142 * kernel command line option that causes the following variable to be set.
143 */
144static bool old_suspend_ordering;
145
146void __init acpi_old_suspend_ordering(void)
147{
148 old_suspend_ordering = true;
149}
150
151static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
152{
153 acpi_old_suspend_ordering();
154 return 0;
155}
156
157static int __init init_nvs_nosave(const struct dmi_system_id *d)
158{
159 acpi_nvs_nosave();
160 return 0;
161}
162
163static bool acpi_sleep_no_lps0;
164
165static int __init init_no_lps0(const struct dmi_system_id *d)
166{
167 acpi_sleep_no_lps0 = true;
168 return 0;
169}
170
171static const struct dmi_system_id acpisleep_dmi_table[] __initconst = {
172 {
173 .callback = init_old_suspend_ordering,
174 .ident = "Abit KN9 (nForce4 variant)",
175 .matches = {
176 DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
177 DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
178 },
179 },
180 {
181 .callback = init_old_suspend_ordering,
182 .ident = "HP xw4600 Workstation",
183 .matches = {
184 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
185 DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
186 },
187 },
188 {
189 .callback = init_old_suspend_ordering,
190 .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
191 .matches = {
192 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
193 DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
194 },
195 },
196 {
197 .callback = init_old_suspend_ordering,
198 .ident = "Panasonic CF51-2L",
199 .matches = {
200 DMI_MATCH(DMI_BOARD_VENDOR,
201 "Matsushita Electric Industrial Co.,Ltd."),
202 DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
203 },
204 },
205 {
206 .callback = init_nvs_nosave,
207 .ident = "Sony Vaio VGN-FW41E_H",
208 .matches = {
209 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
210 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW41E_H"),
211 },
212 },
213 {
214 .callback = init_nvs_nosave,
215 .ident = "Sony Vaio VGN-FW21E",
216 .matches = {
217 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
218 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21E"),
219 },
220 },
221 {
222 .callback = init_nvs_nosave,
223 .ident = "Sony Vaio VGN-FW21M",
224 .matches = {
225 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
226 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21M"),
227 },
228 },
229 {
230 .callback = init_nvs_nosave,
231 .ident = "Sony Vaio VPCEB17FX",
232 .matches = {
233 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
234 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB17FX"),
235 },
236 },
237 {
238 .callback = init_nvs_nosave,
239 .ident = "Sony Vaio VGN-SR11M",
240 .matches = {
241 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
242 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
243 },
244 },
245 {
246 .callback = init_nvs_nosave,
247 .ident = "Everex StepNote Series",
248 .matches = {
249 DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
250 DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
251 },
252 },
253 {
254 .callback = init_nvs_nosave,
255 .ident = "Sony Vaio VPCEB1Z1E",
256 .matches = {
257 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
258 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
259 },
260 },
261 {
262 .callback = init_nvs_nosave,
263 .ident = "Sony Vaio VGN-NW130D",
264 .matches = {
265 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
266 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
267 },
268 },
269 {
270 .callback = init_nvs_nosave,
271 .ident = "Sony Vaio VPCCW29FX",
272 .matches = {
273 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
274 DMI_MATCH(DMI_PRODUCT_NAME, "VPCCW29FX"),
275 },
276 },
277 {
278 .callback = init_nvs_nosave,
279 .ident = "Averatec AV1020-ED2",
280 .matches = {
281 DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
282 DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
283 },
284 },
285 {
286 .callback = init_old_suspend_ordering,
287 .ident = "Asus A8N-SLI DELUXE",
288 .matches = {
289 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
290 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI DELUXE"),
291 },
292 },
293 {
294 .callback = init_old_suspend_ordering,
295 .ident = "Asus A8N-SLI Premium",
296 .matches = {
297 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
298 DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI Premium"),
299 },
300 },
301 {
302 .callback = init_nvs_nosave,
303 .ident = "Sony Vaio VGN-SR26GN_P",
304 .matches = {
305 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
306 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR26GN_P"),
307 },
308 },
309 {
310 .callback = init_nvs_nosave,
311 .ident = "Sony Vaio VPCEB1S1E",
312 .matches = {
313 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
314 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1S1E"),
315 },
316 },
317 {
318 .callback = init_nvs_nosave,
319 .ident = "Sony Vaio VGN-FW520F",
320 .matches = {
321 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
322 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW520F"),
323 },
324 },
325 {
326 .callback = init_nvs_nosave,
327 .ident = "Asus K54C",
328 .matches = {
329 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
330 DMI_MATCH(DMI_PRODUCT_NAME, "K54C"),
331 },
332 },
333 {
334 .callback = init_nvs_nosave,
335 .ident = "Asus K54HR",
336 .matches = {
337 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
338 DMI_MATCH(DMI_PRODUCT_NAME, "K54HR"),
339 },
340 },
341 /*
342 * https://bugzilla.kernel.org/show_bug.cgi?id=189431
343 * Lenovo G50-45 is a platform later than 2012, but needs nvs memory
344 * saving during S3.
345 */
346 {
347 .callback = init_nvs_save_s3,
348 .ident = "Lenovo G50-45",
349 .matches = {
350 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
351 DMI_MATCH(DMI_PRODUCT_NAME, "80E3"),
352 },
353 },
354 /*
355 * https://bugzilla.kernel.org/show_bug.cgi?id=196907
356 * Some Dell XPS13 9360 cannot do suspend-to-idle using the Low Power
357 * S0 Idle firmware interface.
358 */
359 {
360 .callback = init_no_lps0,
361 .ident = "Dell XPS13 9360",
362 .matches = {
363 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
364 DMI_MATCH(DMI_PRODUCT_NAME, "XPS 13 9360"),
365 },
366 },
367 /*
368 * ThinkPad X1 Tablet(2016) cannot do suspend-to-idle using
369 * the Low Power S0 Idle firmware interface (see
370 * https://bugzilla.kernel.org/show_bug.cgi?id=199057).
371 */
372 {
373 .callback = init_no_lps0,
374 .ident = "ThinkPad X1 Tablet(2016)",
375 .matches = {
376 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
377 DMI_MATCH(DMI_PRODUCT_NAME, "20GGA00L00"),
378 },
379 },
380 {},
381};
382
383static bool ignore_blacklist;
384
385void __init acpi_sleep_no_blacklist(void)
386{
387 ignore_blacklist = true;
388}
389
390static void __init acpi_sleep_dmi_check(void)
391{
392 if (ignore_blacklist)
393 return;
394
395 if (dmi_get_bios_year() >= 2012)
396 acpi_nvs_nosave_s3();
397
398 dmi_check_system(acpisleep_dmi_table);
399}
400
401/**
402 * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
403 */
404static int acpi_pm_freeze(void)
405{
406 acpi_disable_all_gpes();
407 acpi_os_wait_events_complete();
408 acpi_ec_block_transactions();
409 return 0;
410}
411
412/**
413 * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
414 */
415static int acpi_pm_pre_suspend(void)
416{
417 acpi_pm_freeze();
418 return suspend_nvs_save();
419}
420
421/**
422 * __acpi_pm_prepare - Prepare the platform to enter the target state.
423 *
424 * If necessary, set the firmware waking vector and do arch-specific
425 * nastiness to get the wakeup code to the waking vector.
426 */
427static int __acpi_pm_prepare(void)
428{
429 int error = acpi_sleep_prepare(acpi_target_sleep_state);
430 if (error)
431 acpi_target_sleep_state = ACPI_STATE_S0;
432
433 return error;
434}
435
436/**
437 * acpi_pm_prepare - Prepare the platform to enter the target sleep
438 * state and disable the GPEs.
439 */
440static int acpi_pm_prepare(void)
441{
442 int error = __acpi_pm_prepare();
443 if (!error)
444 error = acpi_pm_pre_suspend();
445
446 return error;
447}
448
449static int find_powerf_dev(struct device *dev, void *data)
450{
451 struct acpi_device *device = to_acpi_device(dev);
452 const char *hid = acpi_device_hid(device);
453
454 return !strcmp(hid, ACPI_BUTTON_HID_POWERF);
455}
456
457/**
458 * acpi_pm_finish - Instruct the platform to leave a sleep state.
459 *
460 * This is called after we wake back up (or if entering the sleep state
461 * failed).
462 */
463static void acpi_pm_finish(void)
464{
465 struct device *pwr_btn_dev;
466 u32 acpi_state = acpi_target_sleep_state;
467
468 acpi_ec_unblock_transactions();
469 suspend_nvs_free();
470
471 if (acpi_state == ACPI_STATE_S0)
472 return;
473
474 printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
475 acpi_state);
476 acpi_disable_wakeup_devices(acpi_state);
477 acpi_leave_sleep_state(acpi_state);
478
479 /* reset firmware waking vector */
480 acpi_set_waking_vector(0);
481
482 acpi_target_sleep_state = ACPI_STATE_S0;
483
484 acpi_resume_power_resources();
485
486 /* If we were woken with the fixed power button, provide a small
487 * hint to userspace in the form of a wakeup event on the fixed power
488 * button device (if it can be found).
489 *
490 * We delay the event generation til now, as the PM layer requires
491 * timekeeping to be running before we generate events. */
492 if (!pwr_btn_event_pending)
493 return;
494
495 pwr_btn_event_pending = false;
496 pwr_btn_dev = bus_find_device(&acpi_bus_type, NULL, NULL,
497 find_powerf_dev);
498 if (pwr_btn_dev) {
499 pm_wakeup_event(pwr_btn_dev, 0);
500 put_device(pwr_btn_dev);
501 }
502}
503
504/**
505 * acpi_pm_start - Start system PM transition.
506 */
507static void acpi_pm_start(u32 acpi_state)
508{
509 acpi_target_sleep_state = acpi_state;
510 acpi_sleep_tts_switch(acpi_target_sleep_state);
511 acpi_scan_lock_acquire();
512}
513
514/**
515 * acpi_pm_end - Finish up system PM transition.
516 */
517static void acpi_pm_end(void)
518{
519 acpi_turn_off_unused_power_resources();
520 acpi_scan_lock_release();
521 /*
522 * This is necessary in case acpi_pm_finish() is not called during a
523 * failing transition to a sleep state.
524 */
525 acpi_target_sleep_state = ACPI_STATE_S0;
526 acpi_sleep_tts_switch(acpi_target_sleep_state);
527}
528#else /* !CONFIG_ACPI_SLEEP */
529#define acpi_target_sleep_state ACPI_STATE_S0
530#define acpi_sleep_no_lps0 (false)
531static inline void acpi_sleep_dmi_check(void) {}
532#endif /* CONFIG_ACPI_SLEEP */
533
534#ifdef CONFIG_SUSPEND
535static u32 acpi_suspend_states[] = {
536 [PM_SUSPEND_ON] = ACPI_STATE_S0,
537 [PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
538 [PM_SUSPEND_MEM] = ACPI_STATE_S3,
539 [PM_SUSPEND_MAX] = ACPI_STATE_S5
540};
541
542/**
543 * acpi_suspend_begin - Set the target system sleep state to the state
544 * associated with given @pm_state, if supported.
545 */
546static int acpi_suspend_begin(suspend_state_t pm_state)
547{
548 u32 acpi_state = acpi_suspend_states[pm_state];
549 int error;
550
551 error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc();
552 if (error)
553 return error;
554
555 if (!sleep_states[acpi_state]) {
556 pr_err("ACPI does not support sleep state S%u\n", acpi_state);
557 return -ENOSYS;
558 }
559 if (acpi_state > ACPI_STATE_S1)
560 pm_set_suspend_via_firmware();
561
562 acpi_pm_start(acpi_state);
563 return 0;
564}
565
566/**
567 * acpi_suspend_enter - Actually enter a sleep state.
568 * @pm_state: ignored
569 *
570 * Flush caches and go to sleep. For STR we have to call arch-specific
571 * assembly, which in turn call acpi_enter_sleep_state().
572 * It's unfortunate, but it works. Please fix if you're feeling frisky.
573 */
574static int acpi_suspend_enter(suspend_state_t pm_state)
575{
576 acpi_status status = AE_OK;
577 u32 acpi_state = acpi_target_sleep_state;
578 int error;
579
580 ACPI_FLUSH_CPU_CACHE();
581
582 trace_suspend_resume(TPS("acpi_suspend"), acpi_state, true);
583 switch (acpi_state) {
584 case ACPI_STATE_S1:
585 barrier();
586 status = acpi_enter_sleep_state(acpi_state);
587 break;
588
589 case ACPI_STATE_S3:
590 if (!acpi_suspend_lowlevel)
591 return -ENOSYS;
592 error = acpi_suspend_lowlevel();
593 if (error)
594 return error;
595 pr_info(PREFIX "Low-level resume complete\n");
596 pm_set_resume_via_firmware();
597 break;
598 }
599 trace_suspend_resume(TPS("acpi_suspend"), acpi_state, false);
600
601 /* This violates the spec but is required for bug compatibility. */
602 acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
603
604 /* Reprogram control registers */
605 acpi_leave_sleep_state_prep(acpi_state);
606
607 /* ACPI 3.0 specs (P62) says that it's the responsibility
608 * of the OSPM to clear the status bit [ implying that the
609 * POWER_BUTTON event should not reach userspace ]
610 *
611 * However, we do generate a small hint for userspace in the form of
612 * a wakeup event. We flag this condition for now and generate the
613 * event later, as we're currently too early in resume to be able to
614 * generate wakeup events.
615 */
616 if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3)) {
617 acpi_event_status pwr_btn_status = ACPI_EVENT_FLAG_DISABLED;
618
619 acpi_get_event_status(ACPI_EVENT_POWER_BUTTON, &pwr_btn_status);
620
621 if (pwr_btn_status & ACPI_EVENT_FLAG_STATUS_SET) {
622 acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
623 /* Flag for later */
624 pwr_btn_event_pending = true;
625 }
626 }
627
628 /*
629 * Disable and clear GPE status before interrupt is enabled. Some GPEs
630 * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
631 * acpi_leave_sleep_state will reenable specific GPEs later
632 */
633 acpi_disable_all_gpes();
634 /* Allow EC transactions to happen. */
635 acpi_ec_unblock_transactions();
636
637 suspend_nvs_restore();
638
639 return ACPI_SUCCESS(status) ? 0 : -EFAULT;
640}
641
642static int acpi_suspend_state_valid(suspend_state_t pm_state)
643{
644 u32 acpi_state;
645
646 switch (pm_state) {
647 case PM_SUSPEND_ON:
648 case PM_SUSPEND_STANDBY:
649 case PM_SUSPEND_MEM:
650 acpi_state = acpi_suspend_states[pm_state];
651
652 return sleep_states[acpi_state];
653 default:
654 return 0;
655 }
656}
657
658static const struct platform_suspend_ops acpi_suspend_ops = {
659 .valid = acpi_suspend_state_valid,
660 .begin = acpi_suspend_begin,
661 .prepare_late = acpi_pm_prepare,
662 .enter = acpi_suspend_enter,
663 .wake = acpi_pm_finish,
664 .end = acpi_pm_end,
665};
666
667/**
668 * acpi_suspend_begin_old - Set the target system sleep state to the
669 * state associated with given @pm_state, if supported, and
670 * execute the _PTS control method. This function is used if the
671 * pre-ACPI 2.0 suspend ordering has been requested.
672 */
673static int acpi_suspend_begin_old(suspend_state_t pm_state)
674{
675 int error = acpi_suspend_begin(pm_state);
676 if (!error)
677 error = __acpi_pm_prepare();
678
679 return error;
680}
681
682/*
683 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
684 * been requested.
685 */
686static const struct platform_suspend_ops acpi_suspend_ops_old = {
687 .valid = acpi_suspend_state_valid,
688 .begin = acpi_suspend_begin_old,
689 .prepare_late = acpi_pm_pre_suspend,
690 .enter = acpi_suspend_enter,
691 .wake = acpi_pm_finish,
692 .end = acpi_pm_end,
693 .recover = acpi_pm_finish,
694};
695
696static bool s2idle_in_progress;
697static bool s2idle_wakeup;
698
699/*
700 * On platforms supporting the Low Power S0 Idle interface there is an ACPI
701 * device object with the PNP0D80 compatible device ID (System Power Management
702 * Controller) and a specific _DSM method under it. That method, if present,
703 * can be used to indicate to the platform that the OS is transitioning into a
704 * low-power state in which certain types of activity are not desirable or that
705 * it is leaving such a state, which allows the platform to adjust its operation
706 * mode accordingly.
707 */
708static const struct acpi_device_id lps0_device_ids[] = {
709 {"PNP0D80", },
710 {"", },
711};
712
713#define ACPI_LPS0_DSM_UUID "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
714
715#define ACPI_LPS0_GET_DEVICE_CONSTRAINTS 1
716#define ACPI_LPS0_SCREEN_OFF 3
717#define ACPI_LPS0_SCREEN_ON 4
718#define ACPI_LPS0_ENTRY 5
719#define ACPI_LPS0_EXIT 6
720
721#define ACPI_LPS0_SCREEN_MASK ((1 << ACPI_LPS0_SCREEN_OFF) | (1 << ACPI_LPS0_SCREEN_ON))
722#define ACPI_LPS0_PLATFORM_MASK ((1 << ACPI_LPS0_ENTRY) | (1 << ACPI_LPS0_EXIT))
723
724static acpi_handle lps0_device_handle;
725static guid_t lps0_dsm_guid;
726static char lps0_dsm_func_mask;
727
728/* Device constraint entry structure */
729struct lpi_device_info {
730 char *name;
731 int enabled;
732 union acpi_object *package;
733};
734
735/* Constraint package structure */
736struct lpi_device_constraint {
737 int uid;
738 int min_dstate;
739 int function_states;
740};
741
742struct lpi_constraints {
743 acpi_handle handle;
744 int min_dstate;
745};
746
747static struct lpi_constraints *lpi_constraints_table;
748static int lpi_constraints_table_size;
749
750static void lpi_device_get_constraints(void)
751{
752 union acpi_object *out_obj;
753 int i;
754
755 out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
756 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
757 NULL, ACPI_TYPE_PACKAGE);
758
759 acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
760 out_obj ? "successful" : "failed");
761
762 if (!out_obj)
763 return;
764
765 lpi_constraints_table = kcalloc(out_obj->package.count,
766 sizeof(*lpi_constraints_table),
767 GFP_KERNEL);
768 if (!lpi_constraints_table)
769 goto free_acpi_buffer;
770
771 acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
772
773 for (i = 0; i < out_obj->package.count; i++) {
774 struct lpi_constraints *constraint;
775 acpi_status status;
776 union acpi_object *package = &out_obj->package.elements[i];
777 struct lpi_device_info info = { };
778 int package_count = 0, j;
779
780 if (!package)
781 continue;
782
783 for (j = 0; j < package->package.count; ++j) {
784 union acpi_object *element =
785 &(package->package.elements[j]);
786
787 switch (element->type) {
788 case ACPI_TYPE_INTEGER:
789 info.enabled = element->integer.value;
790 break;
791 case ACPI_TYPE_STRING:
792 info.name = element->string.pointer;
793 break;
794 case ACPI_TYPE_PACKAGE:
795 package_count = element->package.count;
796 info.package = element->package.elements;
797 break;
798 }
799 }
800
801 if (!info.enabled || !info.package || !info.name)
802 continue;
803
804 constraint = &lpi_constraints_table[lpi_constraints_table_size];
805
806 status = acpi_get_handle(NULL, info.name, &constraint->handle);
807 if (ACPI_FAILURE(status))
808 continue;
809
810 acpi_handle_debug(lps0_device_handle,
811 "index:%d Name:%s\n", i, info.name);
812
813 constraint->min_dstate = -1;
814
815 for (j = 0; j < package_count; ++j) {
816 union acpi_object *info_obj = &info.package[j];
817 union acpi_object *cnstr_pkg;
818 union acpi_object *obj;
819 struct lpi_device_constraint dev_info;
820
821 switch (info_obj->type) {
822 case ACPI_TYPE_INTEGER:
823 /* version */
824 break;
825 case ACPI_TYPE_PACKAGE:
826 if (info_obj->package.count < 2)
827 break;
828
829 cnstr_pkg = info_obj->package.elements;
830 obj = &cnstr_pkg[0];
831 dev_info.uid = obj->integer.value;
832 obj = &cnstr_pkg[1];
833 dev_info.min_dstate = obj->integer.value;
834
835 acpi_handle_debug(lps0_device_handle,
836 "uid:%d min_dstate:%s\n",
837 dev_info.uid,
838 acpi_power_state_string(dev_info.min_dstate));
839
840 constraint->min_dstate = dev_info.min_dstate;
841 break;
842 }
843 }
844
845 if (constraint->min_dstate < 0) {
846 acpi_handle_debug(lps0_device_handle,
847 "Incomplete constraint defined\n");
848 continue;
849 }
850
851 lpi_constraints_table_size++;
852 }
853
854 acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
855
856free_acpi_buffer:
857 ACPI_FREE(out_obj);
858}
859
860static void lpi_check_constraints(void)
861{
862 int i;
863
864 for (i = 0; i < lpi_constraints_table_size; ++i) {
865 acpi_handle handle = lpi_constraints_table[i].handle;
866 struct acpi_device *adev;
867
868 if (!handle || acpi_bus_get_device(handle, &adev))
869 continue;
870
871 acpi_handle_debug(handle,
872 "LPI: required min power state:%s current power state:%s\n",
873 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
874 acpi_power_state_string(adev->power.state));
875
876 if (!adev->flags.power_manageable) {
877 acpi_handle_info(handle, "LPI: Device not power manageable\n");
878 lpi_constraints_table[i].handle = NULL;
879 continue;
880 }
881
882 if (adev->power.state < lpi_constraints_table[i].min_dstate)
883 acpi_handle_info(handle,
884 "LPI: Constraint not met; min power state:%s current power state:%s\n",
885 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
886 acpi_power_state_string(adev->power.state));
887 }
888}
889
890static void acpi_sleep_run_lps0_dsm(unsigned int func)
891{
892 union acpi_object *out_obj;
893
894 if (!(lps0_dsm_func_mask & (1 << func)))
895 return;
896
897 out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, 1, func, NULL);
898 ACPI_FREE(out_obj);
899
900 acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
901 func, out_obj ? "successful" : "failed");
902}
903
904static int lps0_device_attach(struct acpi_device *adev,
905 const struct acpi_device_id *not_used)
906{
907 union acpi_object *out_obj;
908
909 if (lps0_device_handle)
910 return 0;
911
912 if (acpi_sleep_no_lps0) {
913 acpi_handle_info(adev->handle,
914 "Low Power S0 Idle interface disabled\n");
915 return 0;
916 }
917
918 if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
919 return 0;
920
921 guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
922 /* Check if the _DSM is present and as expected. */
923 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
924 if (out_obj && out_obj->type == ACPI_TYPE_BUFFER) {
925 char bitmask = *(char *)out_obj->buffer.pointer;
926
927 if ((bitmask & ACPI_LPS0_PLATFORM_MASK) == ACPI_LPS0_PLATFORM_MASK ||
928 (bitmask & ACPI_LPS0_SCREEN_MASK) == ACPI_LPS0_SCREEN_MASK) {
929 lps0_dsm_func_mask = bitmask;
930 lps0_device_handle = adev->handle;
931 /*
932 * Use suspend-to-idle by default if the default
933 * suspend mode was not set from the command line.
934 */
935 if (mem_sleep_default > PM_SUSPEND_MEM)
936 mem_sleep_current = PM_SUSPEND_TO_IDLE;
937 }
938
939 acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
940 bitmask);
941 } else {
942 acpi_handle_debug(adev->handle,
943 "_DSM function 0 evaluation failed\n");
944 }
945 ACPI_FREE(out_obj);
946
947 lpi_device_get_constraints();
948
949 return 0;
950}
951
952static struct acpi_scan_handler lps0_handler = {
953 .ids = lps0_device_ids,
954 .attach = lps0_device_attach,
955};
956
957static int acpi_s2idle_begin(void)
958{
959 acpi_scan_lock_acquire();
960 s2idle_in_progress = true;
961 return 0;
962}
963
964static int acpi_s2idle_prepare(void)
965{
966 if (lps0_device_handle) {
967 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
968 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
969 }
970
971 if (acpi_sci_irq_valid())
972 enable_irq_wake(acpi_sci_irq);
973
974 return 0;
975}
976
977static void acpi_s2idle_wake(void)
978{
979
980 if (pm_debug_messages_on)
981 lpi_check_constraints();
982
983 /*
984 * If IRQD_WAKEUP_ARMED is not set for the SCI at this point, it means
985 * that the SCI has triggered while suspended, so cancel the wakeup in
986 * case it has not been a wakeup event (the GPEs will be checked later).
987 */
988 if (acpi_sci_irq_valid() &&
989 !irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq))) {
990 pm_system_cancel_wakeup();
991 s2idle_wakeup = true;
992 }
993}
994
995static void acpi_s2idle_sync(void)
996{
997 /*
998 * Process all pending events in case there are any wakeup ones.
999 *
1000 * The EC driver uses the system workqueue and an additional special
1001 * one, so those need to be flushed too.
1002 */
1003 acpi_os_wait_events_complete(); /* synchronize SCI IRQ handling */
1004 acpi_ec_flush_work();
1005 acpi_os_wait_events_complete(); /* synchronize Notify handling */
1006 s2idle_wakeup = false;
1007}
1008
1009static void acpi_s2idle_restore(void)
1010{
1011 if (acpi_sci_irq_valid())
1012 disable_irq_wake(acpi_sci_irq);
1013
1014 if (lps0_device_handle) {
1015 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
1016 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
1017 }
1018}
1019
1020static void acpi_s2idle_end(void)
1021{
1022 s2idle_in_progress = false;
1023 acpi_scan_lock_release();
1024}
1025
1026static const struct platform_s2idle_ops acpi_s2idle_ops = {
1027 .begin = acpi_s2idle_begin,
1028 .prepare = acpi_s2idle_prepare,
1029 .wake = acpi_s2idle_wake,
1030 .sync = acpi_s2idle_sync,
1031 .restore = acpi_s2idle_restore,
1032 .end = acpi_s2idle_end,
1033};
1034
1035static void acpi_sleep_suspend_setup(void)
1036{
1037 int i;
1038
1039 for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++)
1040 if (acpi_sleep_state_supported(i))
1041 sleep_states[i] = 1;
1042
1043 suspend_set_ops(old_suspend_ordering ?
1044 &acpi_suspend_ops_old : &acpi_suspend_ops);
1045
1046 acpi_scan_add_handler(&lps0_handler);
1047 s2idle_set_ops(&acpi_s2idle_ops);
1048}
1049
1050#else /* !CONFIG_SUSPEND */
1051#define s2idle_in_progress (false)
1052#define s2idle_wakeup (false)
1053#define lps0_device_handle (NULL)
1054static inline void acpi_sleep_suspend_setup(void) {}
1055#endif /* !CONFIG_SUSPEND */
1056
1057bool acpi_s2idle_wakeup(void)
1058{
1059 return s2idle_wakeup;
1060}
1061
1062bool acpi_sleep_no_ec_events(void)
1063{
1064 return !s2idle_in_progress || !lps0_device_handle;
1065}
1066
1067#ifdef CONFIG_PM_SLEEP
1068static u32 saved_bm_rld;
1069
1070static int acpi_save_bm_rld(void)
1071{
1072 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
1073 return 0;
1074}
1075
1076static void acpi_restore_bm_rld(void)
1077{
1078 u32 resumed_bm_rld = 0;
1079
1080 acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
1081 if (resumed_bm_rld == saved_bm_rld)
1082 return;
1083
1084 acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
1085}
1086
1087static struct syscore_ops acpi_sleep_syscore_ops = {
1088 .suspend = acpi_save_bm_rld,
1089 .resume = acpi_restore_bm_rld,
1090};
1091
1092static void acpi_sleep_syscore_init(void)
1093{
1094 register_syscore_ops(&acpi_sleep_syscore_ops);
1095}
1096#else
1097static inline void acpi_sleep_syscore_init(void) {}
1098#endif /* CONFIG_PM_SLEEP */
1099
1100#ifdef CONFIG_HIBERNATION
1101static unsigned long s4_hardware_signature;
1102static struct acpi_table_facs *facs;
1103static bool nosigcheck;
1104
1105void __init acpi_no_s4_hw_signature(void)
1106{
1107 nosigcheck = true;
1108}
1109
1110static int acpi_hibernation_begin(void)
1111{
1112 int error;
1113
1114 error = nvs_nosave ? 0 : suspend_nvs_alloc();
1115 if (!error)
1116 acpi_pm_start(ACPI_STATE_S4);
1117
1118 return error;
1119}
1120
1121static int acpi_hibernation_enter(void)
1122{
1123 acpi_status status = AE_OK;
1124
1125 ACPI_FLUSH_CPU_CACHE();
1126
1127 /* This shouldn't return. If it returns, we have a problem */
1128 status = acpi_enter_sleep_state(ACPI_STATE_S4);
1129 /* Reprogram control registers */
1130 acpi_leave_sleep_state_prep(ACPI_STATE_S4);
1131
1132 return ACPI_SUCCESS(status) ? 0 : -EFAULT;
1133}
1134
1135static void acpi_hibernation_leave(void)
1136{
1137 pm_set_resume_via_firmware();
1138 /*
1139 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
1140 * enable it here.
1141 */
1142 acpi_enable();
1143 /* Reprogram control registers */
1144 acpi_leave_sleep_state_prep(ACPI_STATE_S4);
1145 /* Check the hardware signature */
1146 if (facs && s4_hardware_signature != facs->hardware_signature)
1147 pr_crit("ACPI: Hardware changed while hibernated, success doubtful!\n");
1148 /* Restore the NVS memory area */
1149 suspend_nvs_restore();
1150 /* Allow EC transactions to happen. */
1151 acpi_ec_unblock_transactions();
1152}
1153
1154static void acpi_pm_thaw(void)
1155{
1156 acpi_ec_unblock_transactions();
1157 acpi_enable_all_runtime_gpes();
1158}
1159
1160static const struct platform_hibernation_ops acpi_hibernation_ops = {
1161 .begin = acpi_hibernation_begin,
1162 .end = acpi_pm_end,
1163 .pre_snapshot = acpi_pm_prepare,
1164 .finish = acpi_pm_finish,
1165 .prepare = acpi_pm_prepare,
1166 .enter = acpi_hibernation_enter,
1167 .leave = acpi_hibernation_leave,
1168 .pre_restore = acpi_pm_freeze,
1169 .restore_cleanup = acpi_pm_thaw,
1170};
1171
1172/**
1173 * acpi_hibernation_begin_old - Set the target system sleep state to
1174 * ACPI_STATE_S4 and execute the _PTS control method. This
1175 * function is used if the pre-ACPI 2.0 suspend ordering has been
1176 * requested.
1177 */
1178static int acpi_hibernation_begin_old(void)
1179{
1180 int error;
1181 /*
1182 * The _TTS object should always be evaluated before the _PTS object.
1183 * When the old_suspended_ordering is true, the _PTS object is
1184 * evaluated in the acpi_sleep_prepare.
1185 */
1186 acpi_sleep_tts_switch(ACPI_STATE_S4);
1187
1188 error = acpi_sleep_prepare(ACPI_STATE_S4);
1189
1190 if (!error) {
1191 if (!nvs_nosave)
1192 error = suspend_nvs_alloc();
1193 if (!error) {
1194 acpi_target_sleep_state = ACPI_STATE_S4;
1195 acpi_scan_lock_acquire();
1196 }
1197 }
1198 return error;
1199}
1200
1201/*
1202 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
1203 * been requested.
1204 */
1205static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
1206 .begin = acpi_hibernation_begin_old,
1207 .end = acpi_pm_end,
1208 .pre_snapshot = acpi_pm_pre_suspend,
1209 .prepare = acpi_pm_freeze,
1210 .finish = acpi_pm_finish,
1211 .enter = acpi_hibernation_enter,
1212 .leave = acpi_hibernation_leave,
1213 .pre_restore = acpi_pm_freeze,
1214 .restore_cleanup = acpi_pm_thaw,
1215 .recover = acpi_pm_finish,
1216};
1217
1218static void acpi_sleep_hibernate_setup(void)
1219{
1220 if (!acpi_sleep_state_supported(ACPI_STATE_S4))
1221 return;
1222
1223 hibernation_set_ops(old_suspend_ordering ?
1224 &acpi_hibernation_ops_old : &acpi_hibernation_ops);
1225 sleep_states[ACPI_STATE_S4] = 1;
1226 if (nosigcheck)
1227 return;
1228
1229 acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
1230 if (facs)
1231 s4_hardware_signature = facs->hardware_signature;
1232}
1233#else /* !CONFIG_HIBERNATION */
1234static inline void acpi_sleep_hibernate_setup(void) {}
1235#endif /* !CONFIG_HIBERNATION */
1236
1237static void acpi_power_off_prepare(void)
1238{
1239 /* Prepare to power off the system */
1240 acpi_sleep_prepare(ACPI_STATE_S5);
1241 acpi_disable_all_gpes();
1242 acpi_os_wait_events_complete();
1243}
1244
1245static void acpi_power_off(void)
1246{
1247 /* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
1248 printk(KERN_DEBUG "%s called\n", __func__);
1249 local_irq_disable();
1250 acpi_enter_sleep_state(ACPI_STATE_S5);
1251}
1252
1253int __init acpi_sleep_init(void)
1254{
1255 char supported[ACPI_S_STATE_COUNT * 3 + 1];
1256 char *pos = supported;
1257 int i;
1258
1259 acpi_sleep_dmi_check();
1260
1261 sleep_states[ACPI_STATE_S0] = 1;
1262
1263 acpi_sleep_syscore_init();
1264 acpi_sleep_suspend_setup();
1265 acpi_sleep_hibernate_setup();
1266
1267 if (acpi_sleep_state_supported(ACPI_STATE_S5)) {
1268 sleep_states[ACPI_STATE_S5] = 1;
1269 pm_power_off_prepare = acpi_power_off_prepare;
1270 pm_power_off = acpi_power_off;
1271 } else {
1272 acpi_no_s5 = true;
1273 }
1274
1275 supported[0] = 0;
1276 for (i = 0; i < ACPI_S_STATE_COUNT; i++) {
1277 if (sleep_states[i])
1278 pos += sprintf(pos, " S%d", i);
1279 }
1280 pr_info(PREFIX "(supports%s)\n", supported);
1281
1282 /*
1283 * Register the tts_notifier to reboot notifier list so that the _TTS
1284 * object can also be evaluated when the system enters S5.
1285 */
1286 register_reboot_notifier(&tts_notifier);
1287 return 0;
1288}