xref: /openbmc/linux/drivers/acpi/sleep.c (revision 82003e04)
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  */
33 bool acpi_no_s5;
34 static u8 sleep_states[ACPI_S_STATE_COUNT];
35 
36 static 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 
50 static void acpi_sleep_pts_switch(u32 acpi_state)
51 {
52 	acpi_status status;
53 
54 	status = acpi_execute_simple_method(NULL, "\\_PTS", acpi_state);
55 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
56 		/*
57 		 * OS can't evaluate the _PTS object correctly. Some warning
58 		 * message will be printed. But it won't break anything.
59 		 */
60 		printk(KERN_NOTICE "Failure in evaluating _PTS object\n");
61 	}
62 }
63 
64 static int sleep_notify_reboot(struct notifier_block *this,
65 			unsigned long code, void *x)
66 {
67 	acpi_sleep_tts_switch(ACPI_STATE_S5);
68 
69 	acpi_sleep_pts_switch(ACPI_STATE_S5);
70 
71 	return NOTIFY_DONE;
72 }
73 
74 static struct notifier_block sleep_notifier = {
75 	.notifier_call	= sleep_notify_reboot,
76 	.next		= NULL,
77 	.priority	= 0,
78 };
79 
80 static int acpi_sleep_prepare(u32 acpi_state)
81 {
82 #ifdef CONFIG_ACPI_SLEEP
83 	/* do we have a wakeup address for S2 and S3? */
84 	if (acpi_state == ACPI_STATE_S3) {
85 		if (!acpi_wakeup_address)
86 			return -EFAULT;
87 		acpi_set_waking_vector(acpi_wakeup_address);
88 
89 	}
90 	ACPI_FLUSH_CPU_CACHE();
91 #endif
92 	printk(KERN_INFO PREFIX "Preparing to enter system sleep state S%d\n",
93 		acpi_state);
94 	acpi_enable_wakeup_devices(acpi_state);
95 	acpi_enter_sleep_state_prep(acpi_state);
96 	return 0;
97 }
98 
99 static bool acpi_sleep_state_supported(u8 sleep_state)
100 {
101 	acpi_status status;
102 	u8 type_a, type_b;
103 
104 	status = acpi_get_sleep_type_data(sleep_state, &type_a, &type_b);
105 	return ACPI_SUCCESS(status) && (!acpi_gbl_reduced_hardware
106 		|| (acpi_gbl_FADT.sleep_control.address
107 			&& acpi_gbl_FADT.sleep_status.address));
108 }
109 
110 #ifdef CONFIG_ACPI_SLEEP
111 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
112 
113 u32 acpi_target_system_state(void)
114 {
115 	return acpi_target_sleep_state;
116 }
117 EXPORT_SYMBOL_GPL(acpi_target_system_state);
118 
119 static bool pwr_btn_event_pending;
120 
121 /*
122  * The ACPI specification wants us to save NVS memory regions during hibernation
123  * and to restore them during the subsequent resume.  Windows does that also for
124  * suspend to RAM.  However, it is known that this mechanism does not work on
125  * all machines, so we allow the user to disable it with the help of the
126  * 'acpi_sleep=nonvs' kernel command line option.
127  */
128 static bool nvs_nosave;
129 
130 void __init acpi_nvs_nosave(void)
131 {
132 	nvs_nosave = true;
133 }
134 
135 /*
136  * The ACPI specification wants us to save NVS memory regions during hibernation
137  * but says nothing about saving NVS during S3.  Not all versions of Windows
138  * save NVS on S3 suspend either, and it is clear that not all systems need
139  * NVS to be saved at S3 time.  To improve suspend/resume time, allow the
140  * user to disable saving NVS on S3 if their system does not require it, but
141  * continue to save/restore NVS for S4 as specified.
142  */
143 static bool nvs_nosave_s3;
144 
145 void __init acpi_nvs_nosave_s3(void)
146 {
147 	nvs_nosave_s3 = true;
148 }
149 
150 /*
151  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
152  * user to request that behavior by using the 'acpi_old_suspend_ordering'
153  * kernel command line option that causes the following variable to be set.
154  */
155 static bool old_suspend_ordering;
156 
157 void __init acpi_old_suspend_ordering(void)
158 {
159 	old_suspend_ordering = true;
160 }
161 
162 static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
163 {
164 	acpi_old_suspend_ordering();
165 	return 0;
166 }
167 
168 static int __init init_nvs_nosave(const struct dmi_system_id *d)
169 {
170 	acpi_nvs_nosave();
171 	return 0;
172 }
173 
174 static struct dmi_system_id acpisleep_dmi_table[] __initdata = {
175 	{
176 	.callback = init_old_suspend_ordering,
177 	.ident = "Abit KN9 (nForce4 variant)",
178 	.matches = {
179 		DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
180 		DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
181 		},
182 	},
183 	{
184 	.callback = init_old_suspend_ordering,
185 	.ident = "HP xw4600 Workstation",
186 	.matches = {
187 		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
188 		DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
189 		},
190 	},
191 	{
192 	.callback = init_old_suspend_ordering,
193 	.ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
194 	.matches = {
195 		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
196 		DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
197 		},
198 	},
199 	{
200 	.callback = init_old_suspend_ordering,
201 	.ident = "Panasonic CF51-2L",
202 	.matches = {
203 		DMI_MATCH(DMI_BOARD_VENDOR,
204 				"Matsushita Electric Industrial Co.,Ltd."),
205 		DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
206 		},
207 	},
208 	{
209 	.callback = init_nvs_nosave,
210 	.ident = "Sony Vaio VGN-FW41E_H",
211 	.matches = {
212 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
213 		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW41E_H"),
214 		},
215 	},
216 	{
217 	.callback = init_nvs_nosave,
218 	.ident = "Sony Vaio VGN-FW21E",
219 	.matches = {
220 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
221 		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21E"),
222 		},
223 	},
224 	{
225 	.callback = init_nvs_nosave,
226 	.ident = "Sony Vaio VGN-FW21M",
227 	.matches = {
228 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
229 		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21M"),
230 		},
231 	},
232 	{
233 	.callback = init_nvs_nosave,
234 	.ident = "Sony Vaio VPCEB17FX",
235 	.matches = {
236 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
237 		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB17FX"),
238 		},
239 	},
240 	{
241 	.callback = init_nvs_nosave,
242 	.ident = "Sony Vaio VGN-SR11M",
243 	.matches = {
244 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
245 		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
246 		},
247 	},
248 	{
249 	.callback = init_nvs_nosave,
250 	.ident = "Everex StepNote Series",
251 	.matches = {
252 		DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
253 		DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
254 		},
255 	},
256 	{
257 	.callback = init_nvs_nosave,
258 	.ident = "Sony Vaio VPCEB1Z1E",
259 	.matches = {
260 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
261 		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
262 		},
263 	},
264 	{
265 	.callback = init_nvs_nosave,
266 	.ident = "Sony Vaio VGN-NW130D",
267 	.matches = {
268 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
269 		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
270 		},
271 	},
272 	{
273 	.callback = init_nvs_nosave,
274 	.ident = "Sony Vaio VPCCW29FX",
275 	.matches = {
276 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
277 		DMI_MATCH(DMI_PRODUCT_NAME, "VPCCW29FX"),
278 		},
279 	},
280 	{
281 	.callback = init_nvs_nosave,
282 	.ident = "Averatec AV1020-ED2",
283 	.matches = {
284 		DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
285 		DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
286 		},
287 	},
288 	{
289 	.callback = init_old_suspend_ordering,
290 	.ident = "Asus A8N-SLI DELUXE",
291 	.matches = {
292 		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
293 		DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI DELUXE"),
294 		},
295 	},
296 	{
297 	.callback = init_old_suspend_ordering,
298 	.ident = "Asus A8N-SLI Premium",
299 	.matches = {
300 		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
301 		DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI Premium"),
302 		},
303 	},
304 	{
305 	.callback = init_nvs_nosave,
306 	.ident = "Sony Vaio VGN-SR26GN_P",
307 	.matches = {
308 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
309 		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR26GN_P"),
310 		},
311 	},
312 	{
313 	.callback = init_nvs_nosave,
314 	.ident = "Sony Vaio VPCEB1S1E",
315 	.matches = {
316 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
317 		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1S1E"),
318 		},
319 	},
320 	{
321 	.callback = init_nvs_nosave,
322 	.ident = "Sony Vaio VGN-FW520F",
323 	.matches = {
324 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
325 		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW520F"),
326 		},
327 	},
328 	{
329 	.callback = init_nvs_nosave,
330 	.ident = "Asus K54C",
331 	.matches = {
332 		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
333 		DMI_MATCH(DMI_PRODUCT_NAME, "K54C"),
334 		},
335 	},
336 	{
337 	.callback = init_nvs_nosave,
338 	.ident = "Asus K54HR",
339 	.matches = {
340 		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
341 		DMI_MATCH(DMI_PRODUCT_NAME, "K54HR"),
342 		},
343 	},
344 	{},
345 };
346 
347 static void __init acpi_sleep_dmi_check(void)
348 {
349 	int year;
350 
351 	if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && year >= 2012)
352 		acpi_nvs_nosave_s3();
353 
354 	dmi_check_system(acpisleep_dmi_table);
355 }
356 
357 /**
358  * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
359  */
360 static int acpi_pm_freeze(void)
361 {
362 	acpi_disable_all_gpes();
363 	acpi_os_wait_events_complete();
364 	acpi_ec_block_transactions();
365 	return 0;
366 }
367 
368 /**
369  * acpi_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
370  */
371 static int acpi_pm_pre_suspend(void)
372 {
373 	acpi_pm_freeze();
374 	return suspend_nvs_save();
375 }
376 
377 /**
378  *	__acpi_pm_prepare - Prepare the platform to enter the target state.
379  *
380  *	If necessary, set the firmware waking vector and do arch-specific
381  *	nastiness to get the wakeup code to the waking vector.
382  */
383 static int __acpi_pm_prepare(void)
384 {
385 	int error = acpi_sleep_prepare(acpi_target_sleep_state);
386 	if (error)
387 		acpi_target_sleep_state = ACPI_STATE_S0;
388 
389 	return error;
390 }
391 
392 /**
393  *	acpi_pm_prepare - Prepare the platform to enter the target sleep
394  *		state and disable the GPEs.
395  */
396 static int acpi_pm_prepare(void)
397 {
398 	int error = __acpi_pm_prepare();
399 	if (!error)
400 		error = acpi_pm_pre_suspend();
401 
402 	return error;
403 }
404 
405 static int find_powerf_dev(struct device *dev, void *data)
406 {
407 	struct acpi_device *device = to_acpi_device(dev);
408 	const char *hid = acpi_device_hid(device);
409 
410 	return !strcmp(hid, ACPI_BUTTON_HID_POWERF);
411 }
412 
413 /**
414  *	acpi_pm_finish - Instruct the platform to leave a sleep state.
415  *
416  *	This is called after we wake back up (or if entering the sleep state
417  *	failed).
418  */
419 static void acpi_pm_finish(void)
420 {
421 	struct device *pwr_btn_dev;
422 	u32 acpi_state = acpi_target_sleep_state;
423 
424 	acpi_ec_unblock_transactions();
425 	suspend_nvs_free();
426 
427 	if (acpi_state == ACPI_STATE_S0)
428 		return;
429 
430 	printk(KERN_INFO PREFIX "Waking up from system sleep state S%d\n",
431 		acpi_state);
432 	acpi_disable_wakeup_devices(acpi_state);
433 	acpi_leave_sleep_state(acpi_state);
434 
435 	/* reset firmware waking vector */
436 	acpi_set_waking_vector(0);
437 
438 	acpi_target_sleep_state = ACPI_STATE_S0;
439 
440 	acpi_resume_power_resources();
441 
442 	/* If we were woken with the fixed power button, provide a small
443 	 * hint to userspace in the form of a wakeup event on the fixed power
444 	 * button device (if it can be found).
445 	 *
446 	 * We delay the event generation til now, as the PM layer requires
447 	 * timekeeping to be running before we generate events. */
448 	if (!pwr_btn_event_pending)
449 		return;
450 
451 	pwr_btn_event_pending = false;
452 	pwr_btn_dev = bus_find_device(&acpi_bus_type, NULL, NULL,
453 				      find_powerf_dev);
454 	if (pwr_btn_dev) {
455 		pm_wakeup_event(pwr_btn_dev, 0);
456 		put_device(pwr_btn_dev);
457 	}
458 }
459 
460 /**
461  * acpi_pm_start - Start system PM transition.
462  */
463 static void acpi_pm_start(u32 acpi_state)
464 {
465 	acpi_target_sleep_state = acpi_state;
466 	acpi_sleep_tts_switch(acpi_target_sleep_state);
467 	acpi_scan_lock_acquire();
468 }
469 
470 /**
471  * acpi_pm_end - Finish up system PM transition.
472  */
473 static void acpi_pm_end(void)
474 {
475 	acpi_scan_lock_release();
476 	/*
477 	 * This is necessary in case acpi_pm_finish() is not called during a
478 	 * failing transition to a sleep state.
479 	 */
480 	acpi_target_sleep_state = ACPI_STATE_S0;
481 	acpi_sleep_tts_switch(acpi_target_sleep_state);
482 }
483 #else /* !CONFIG_ACPI_SLEEP */
484 #define acpi_target_sleep_state	ACPI_STATE_S0
485 static inline void acpi_sleep_dmi_check(void) {}
486 #endif /* CONFIG_ACPI_SLEEP */
487 
488 #ifdef CONFIG_SUSPEND
489 static u32 acpi_suspend_states[] = {
490 	[PM_SUSPEND_ON] = ACPI_STATE_S0,
491 	[PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
492 	[PM_SUSPEND_MEM] = ACPI_STATE_S3,
493 	[PM_SUSPEND_MAX] = ACPI_STATE_S5
494 };
495 
496 /**
497  *	acpi_suspend_begin - Set the target system sleep state to the state
498  *		associated with given @pm_state, if supported.
499  */
500 static int acpi_suspend_begin(suspend_state_t pm_state)
501 {
502 	u32 acpi_state = acpi_suspend_states[pm_state];
503 	int error;
504 
505 	error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc();
506 	if (error)
507 		return error;
508 
509 	if (!sleep_states[acpi_state]) {
510 		pr_err("ACPI does not support sleep state S%u\n", acpi_state);
511 		return -ENOSYS;
512 	}
513 	if (acpi_state > ACPI_STATE_S1)
514 		pm_set_suspend_via_firmware();
515 
516 	acpi_pm_start(acpi_state);
517 	return 0;
518 }
519 
520 /**
521  *	acpi_suspend_enter - Actually enter a sleep state.
522  *	@pm_state: ignored
523  *
524  *	Flush caches and go to sleep. For STR we have to call arch-specific
525  *	assembly, which in turn call acpi_enter_sleep_state().
526  *	It's unfortunate, but it works. Please fix if you're feeling frisky.
527  */
528 static int acpi_suspend_enter(suspend_state_t pm_state)
529 {
530 	acpi_status status = AE_OK;
531 	u32 acpi_state = acpi_target_sleep_state;
532 	int error;
533 
534 	ACPI_FLUSH_CPU_CACHE();
535 
536 	trace_suspend_resume(TPS("acpi_suspend"), acpi_state, true);
537 	switch (acpi_state) {
538 	case ACPI_STATE_S1:
539 		barrier();
540 		status = acpi_enter_sleep_state(acpi_state);
541 		break;
542 
543 	case ACPI_STATE_S3:
544 		if (!acpi_suspend_lowlevel)
545 			return -ENOSYS;
546 		error = acpi_suspend_lowlevel();
547 		if (error)
548 			return error;
549 		pr_info(PREFIX "Low-level resume complete\n");
550 		pm_set_resume_via_firmware();
551 		break;
552 	}
553 	trace_suspend_resume(TPS("acpi_suspend"), acpi_state, false);
554 
555 	/* This violates the spec but is required for bug compatibility. */
556 	acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
557 
558 	/* Reprogram control registers */
559 	acpi_leave_sleep_state_prep(acpi_state);
560 
561 	/* ACPI 3.0 specs (P62) says that it's the responsibility
562 	 * of the OSPM to clear the status bit [ implying that the
563 	 * POWER_BUTTON event should not reach userspace ]
564 	 *
565 	 * However, we do generate a small hint for userspace in the form of
566 	 * a wakeup event. We flag this condition for now and generate the
567 	 * event later, as we're currently too early in resume to be able to
568 	 * generate wakeup events.
569 	 */
570 	if (ACPI_SUCCESS(status) && (acpi_state == ACPI_STATE_S3)) {
571 		acpi_event_status pwr_btn_status = ACPI_EVENT_FLAG_DISABLED;
572 
573 		acpi_get_event_status(ACPI_EVENT_POWER_BUTTON, &pwr_btn_status);
574 
575 		if (pwr_btn_status & ACPI_EVENT_FLAG_STATUS_SET) {
576 			acpi_clear_event(ACPI_EVENT_POWER_BUTTON);
577 			/* Flag for later */
578 			pwr_btn_event_pending = true;
579 		}
580 	}
581 
582 	/*
583 	 * Disable and clear GPE status before interrupt is enabled. Some GPEs
584 	 * (like wakeup GPE) haven't handler, this can avoid such GPE misfire.
585 	 * acpi_leave_sleep_state will reenable specific GPEs later
586 	 */
587 	acpi_disable_all_gpes();
588 	/* Allow EC transactions to happen. */
589 	acpi_ec_unblock_transactions();
590 
591 	suspend_nvs_restore();
592 
593 	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
594 }
595 
596 static int acpi_suspend_state_valid(suspend_state_t pm_state)
597 {
598 	u32 acpi_state;
599 
600 	switch (pm_state) {
601 	case PM_SUSPEND_ON:
602 	case PM_SUSPEND_STANDBY:
603 	case PM_SUSPEND_MEM:
604 		acpi_state = acpi_suspend_states[pm_state];
605 
606 		return sleep_states[acpi_state];
607 	default:
608 		return 0;
609 	}
610 }
611 
612 static const struct platform_suspend_ops acpi_suspend_ops = {
613 	.valid = acpi_suspend_state_valid,
614 	.begin = acpi_suspend_begin,
615 	.prepare_late = acpi_pm_prepare,
616 	.enter = acpi_suspend_enter,
617 	.wake = acpi_pm_finish,
618 	.end = acpi_pm_end,
619 };
620 
621 /**
622  *	acpi_suspend_begin_old - Set the target system sleep state to the
623  *		state associated with given @pm_state, if supported, and
624  *		execute the _PTS control method.  This function is used if the
625  *		pre-ACPI 2.0 suspend ordering has been requested.
626  */
627 static int acpi_suspend_begin_old(suspend_state_t pm_state)
628 {
629 	int error = acpi_suspend_begin(pm_state);
630 	if (!error)
631 		error = __acpi_pm_prepare();
632 
633 	return error;
634 }
635 
636 /*
637  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
638  * been requested.
639  */
640 static const struct platform_suspend_ops acpi_suspend_ops_old = {
641 	.valid = acpi_suspend_state_valid,
642 	.begin = acpi_suspend_begin_old,
643 	.prepare_late = acpi_pm_pre_suspend,
644 	.enter = acpi_suspend_enter,
645 	.wake = acpi_pm_finish,
646 	.end = acpi_pm_end,
647 	.recover = acpi_pm_finish,
648 };
649 
650 static int acpi_freeze_begin(void)
651 {
652 	acpi_scan_lock_acquire();
653 	return 0;
654 }
655 
656 static int acpi_freeze_prepare(void)
657 {
658 	acpi_enable_wakeup_devices(ACPI_STATE_S0);
659 	acpi_enable_all_wakeup_gpes();
660 	acpi_os_wait_events_complete();
661 	if (acpi_sci_irq_valid())
662 		enable_irq_wake(acpi_sci_irq);
663 	return 0;
664 }
665 
666 static void acpi_freeze_restore(void)
667 {
668 	acpi_disable_wakeup_devices(ACPI_STATE_S0);
669 	if (acpi_sci_irq_valid())
670 		disable_irq_wake(acpi_sci_irq);
671 	acpi_enable_all_runtime_gpes();
672 }
673 
674 static void acpi_freeze_end(void)
675 {
676 	acpi_scan_lock_release();
677 }
678 
679 static const struct platform_freeze_ops acpi_freeze_ops = {
680 	.begin = acpi_freeze_begin,
681 	.prepare = acpi_freeze_prepare,
682 	.restore = acpi_freeze_restore,
683 	.end = acpi_freeze_end,
684 };
685 
686 static void acpi_sleep_suspend_setup(void)
687 {
688 	int i;
689 
690 	for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++)
691 		if (acpi_sleep_state_supported(i))
692 			sleep_states[i] = 1;
693 
694 	suspend_set_ops(old_suspend_ordering ?
695 		&acpi_suspend_ops_old : &acpi_suspend_ops);
696 	freeze_set_ops(&acpi_freeze_ops);
697 }
698 
699 #else /* !CONFIG_SUSPEND */
700 static inline void acpi_sleep_suspend_setup(void) {}
701 #endif /* !CONFIG_SUSPEND */
702 
703 #ifdef CONFIG_PM_SLEEP
704 static u32 saved_bm_rld;
705 
706 static int  acpi_save_bm_rld(void)
707 {
708 	acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
709 	return 0;
710 }
711 
712 static void  acpi_restore_bm_rld(void)
713 {
714 	u32 resumed_bm_rld = 0;
715 
716 	acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
717 	if (resumed_bm_rld == saved_bm_rld)
718 		return;
719 
720 	acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
721 }
722 
723 static struct syscore_ops acpi_sleep_syscore_ops = {
724 	.suspend = acpi_save_bm_rld,
725 	.resume = acpi_restore_bm_rld,
726 };
727 
728 void acpi_sleep_syscore_init(void)
729 {
730 	register_syscore_ops(&acpi_sleep_syscore_ops);
731 }
732 #else
733 static inline void acpi_sleep_syscore_init(void) {}
734 #endif /* CONFIG_PM_SLEEP */
735 
736 #ifdef CONFIG_HIBERNATION
737 static unsigned long s4_hardware_signature;
738 static struct acpi_table_facs *facs;
739 static bool nosigcheck;
740 
741 void __init acpi_no_s4_hw_signature(void)
742 {
743 	nosigcheck = true;
744 }
745 
746 static int acpi_hibernation_begin(void)
747 {
748 	int error;
749 
750 	error = nvs_nosave ? 0 : suspend_nvs_alloc();
751 	if (!error)
752 		acpi_pm_start(ACPI_STATE_S4);
753 
754 	return error;
755 }
756 
757 static int acpi_hibernation_enter(void)
758 {
759 	acpi_status status = AE_OK;
760 
761 	ACPI_FLUSH_CPU_CACHE();
762 
763 	/* This shouldn't return.  If it returns, we have a problem */
764 	status = acpi_enter_sleep_state(ACPI_STATE_S4);
765 	/* Reprogram control registers */
766 	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
767 
768 	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
769 }
770 
771 static void acpi_hibernation_leave(void)
772 {
773 	pm_set_resume_via_firmware();
774 	/*
775 	 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
776 	 * enable it here.
777 	 */
778 	acpi_enable();
779 	/* Reprogram control registers */
780 	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
781 	/* Check the hardware signature */
782 	if (facs && s4_hardware_signature != facs->hardware_signature)
783 		pr_crit("ACPI: Hardware changed while hibernated, success doubtful!\n");
784 	/* Restore the NVS memory area */
785 	suspend_nvs_restore();
786 	/* Allow EC transactions to happen. */
787 	acpi_ec_unblock_transactions();
788 }
789 
790 static void acpi_pm_thaw(void)
791 {
792 	acpi_ec_unblock_transactions();
793 	acpi_enable_all_runtime_gpes();
794 }
795 
796 static const struct platform_hibernation_ops acpi_hibernation_ops = {
797 	.begin = acpi_hibernation_begin,
798 	.end = acpi_pm_end,
799 	.pre_snapshot = acpi_pm_prepare,
800 	.finish = acpi_pm_finish,
801 	.prepare = acpi_pm_prepare,
802 	.enter = acpi_hibernation_enter,
803 	.leave = acpi_hibernation_leave,
804 	.pre_restore = acpi_pm_freeze,
805 	.restore_cleanup = acpi_pm_thaw,
806 };
807 
808 /**
809  *	acpi_hibernation_begin_old - Set the target system sleep state to
810  *		ACPI_STATE_S4 and execute the _PTS control method.  This
811  *		function is used if the pre-ACPI 2.0 suspend ordering has been
812  *		requested.
813  */
814 static int acpi_hibernation_begin_old(void)
815 {
816 	int error;
817 	/*
818 	 * The _TTS object should always be evaluated before the _PTS object.
819 	 * When the old_suspended_ordering is true, the _PTS object is
820 	 * evaluated in the acpi_sleep_prepare.
821 	 */
822 	acpi_sleep_tts_switch(ACPI_STATE_S4);
823 
824 	error = acpi_sleep_prepare(ACPI_STATE_S4);
825 
826 	if (!error) {
827 		if (!nvs_nosave)
828 			error = suspend_nvs_alloc();
829 		if (!error) {
830 			acpi_target_sleep_state = ACPI_STATE_S4;
831 			acpi_scan_lock_acquire();
832 		}
833 	}
834 	return error;
835 }
836 
837 /*
838  * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
839  * been requested.
840  */
841 static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
842 	.begin = acpi_hibernation_begin_old,
843 	.end = acpi_pm_end,
844 	.pre_snapshot = acpi_pm_pre_suspend,
845 	.prepare = acpi_pm_freeze,
846 	.finish = acpi_pm_finish,
847 	.enter = acpi_hibernation_enter,
848 	.leave = acpi_hibernation_leave,
849 	.pre_restore = acpi_pm_freeze,
850 	.restore_cleanup = acpi_pm_thaw,
851 	.recover = acpi_pm_finish,
852 };
853 
854 static void acpi_sleep_hibernate_setup(void)
855 {
856 	if (!acpi_sleep_state_supported(ACPI_STATE_S4))
857 		return;
858 
859 	hibernation_set_ops(old_suspend_ordering ?
860 			&acpi_hibernation_ops_old : &acpi_hibernation_ops);
861 	sleep_states[ACPI_STATE_S4] = 1;
862 	if (nosigcheck)
863 		return;
864 
865 	acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
866 	if (facs)
867 		s4_hardware_signature = facs->hardware_signature;
868 }
869 #else /* !CONFIG_HIBERNATION */
870 static inline void acpi_sleep_hibernate_setup(void) {}
871 #endif /* !CONFIG_HIBERNATION */
872 
873 static void acpi_power_off_prepare(void)
874 {
875 	/* Prepare to power off the system */
876 	acpi_sleep_prepare(ACPI_STATE_S5);
877 	acpi_disable_all_gpes();
878 	acpi_os_wait_events_complete();
879 }
880 
881 static void acpi_power_off(void)
882 {
883 	/* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
884 	printk(KERN_DEBUG "%s called\n", __func__);
885 	local_irq_disable();
886 	acpi_enter_sleep_state(ACPI_STATE_S5);
887 }
888 
889 int __init acpi_sleep_init(void)
890 {
891 	char supported[ACPI_S_STATE_COUNT * 3 + 1];
892 	char *pos = supported;
893 	int i;
894 
895 	acpi_sleep_dmi_check();
896 
897 	sleep_states[ACPI_STATE_S0] = 1;
898 
899 	acpi_sleep_syscore_init();
900 	acpi_sleep_suspend_setup();
901 	acpi_sleep_hibernate_setup();
902 
903 	if (acpi_sleep_state_supported(ACPI_STATE_S5)) {
904 		sleep_states[ACPI_STATE_S5] = 1;
905 		pm_power_off_prepare = acpi_power_off_prepare;
906 		pm_power_off = acpi_power_off;
907 	} else {
908 		acpi_no_s5 = true;
909 	}
910 
911 	supported[0] = 0;
912 	for (i = 0; i < ACPI_S_STATE_COUNT; i++) {
913 		if (sleep_states[i])
914 			pos += sprintf(pos, " S%d", i);
915 	}
916 	pr_info(PREFIX "(supports%s)\n", supported);
917 
918 	/*
919 	 * Register the sleep_notifier to reboot notifier list so that the _TTS
920 	 * and _PTS object can also be evaluated when the system enters S5.
921 	 */
922 	register_reboot_notifier(&sleep_notifier);
923 	return 0;
924 }
925