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v3.1
 
  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}
v6.9.4
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * sleep.c - ACPI sleep support.
   4 *
   5 * Copyright (c) 2005 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   6 * Copyright (c) 2004 David Shaohua Li <shaohua.li@intel.com>
   7 * Copyright (c) 2000-2003 Patrick Mochel
   8 * Copyright (c) 2003 Open Source Development Lab
 
 
 
   9 */
  10
  11#define pr_fmt(fmt) "ACPI: PM: " fmt
  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		pr_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
  63#ifndef acpi_skip_set_wakeup_address
  64#define acpi_skip_set_wakeup_address() false
  65#endif
  66
  67static int acpi_sleep_prepare(u32 acpi_state)
  68{
  69#ifdef CONFIG_ACPI_SLEEP
  70	unsigned long acpi_wakeup_address;
  71
  72	/* do we have a wakeup address for S2 and S3? */
  73	if (acpi_state == ACPI_STATE_S3 && !acpi_skip_set_wakeup_address()) {
  74		acpi_wakeup_address = acpi_get_wakeup_address();
  75		if (!acpi_wakeup_address)
  76			return -EFAULT;
  77		acpi_set_waking_vector(acpi_wakeup_address);
 
 
  78
  79	}
 
  80#endif
  81	pr_info("Preparing to enter system sleep state S%d\n", acpi_state);
 
  82	acpi_enable_wakeup_devices(acpi_state);
  83	acpi_enter_sleep_state_prep(acpi_state);
  84	return 0;
  85}
  86
  87bool acpi_sleep_state_supported(u8 sleep_state)
  88{
  89	acpi_status status;
  90	u8 type_a, type_b;
  91
  92	status = acpi_get_sleep_type_data(sleep_state, &type_a, &type_b);
  93	return ACPI_SUCCESS(status) && (!acpi_gbl_reduced_hardware
  94		|| (acpi_gbl_FADT.sleep_control.address
  95			&& acpi_gbl_FADT.sleep_status.address));
  96}
  97
  98#ifdef CONFIG_ACPI_SLEEP
  99static u32 acpi_target_sleep_state = ACPI_STATE_S0;
 100
 101u32 acpi_target_system_state(void)
 102{
 103	return acpi_target_sleep_state;
 104}
 105EXPORT_SYMBOL_GPL(acpi_target_system_state);
 106
 107static bool pwr_btn_event_pending;
 108
 109/*
 110 * The ACPI specification wants us to save NVS memory regions during hibernation
 111 * and to restore them during the subsequent resume.  Windows does that also for
 112 * suspend to RAM.  However, it is known that this mechanism does not work on
 113 * all machines, so we allow the user to disable it with the help of the
 114 * 'acpi_sleep=nonvs' kernel command line option.
 115 */
 116static bool nvs_nosave;
 117
 118void __init acpi_nvs_nosave(void)
 119{
 120	nvs_nosave = true;
 121}
 122
 123/*
 124 * The ACPI specification wants us to save NVS memory regions during hibernation
 125 * but says nothing about saving NVS during S3.  Not all versions of Windows
 126 * save NVS on S3 suspend either, and it is clear that not all systems need
 127 * NVS to be saved at S3 time.  To improve suspend/resume time, allow the
 128 * user to disable saving NVS on S3 if their system does not require it, but
 129 * continue to save/restore NVS for S4 as specified.
 130 */
 131static bool nvs_nosave_s3;
 132
 133void __init acpi_nvs_nosave_s3(void)
 134{
 135	nvs_nosave_s3 = true;
 136}
 137
 138static int __init init_nvs_save_s3(const struct dmi_system_id *d)
 139{
 140	nvs_nosave_s3 = false;
 141	return 0;
 142}
 143
 144/*
 145 * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
 146 * user to request that behavior by using the 'acpi_old_suspend_ordering'
 147 * kernel command line option that causes the following variable to be set.
 148 */
 149static bool old_suspend_ordering;
 150
 151void __init acpi_old_suspend_ordering(void)
 152{
 153	old_suspend_ordering = true;
 154}
 155
 156static int __init init_old_suspend_ordering(const struct dmi_system_id *d)
 157{
 158	acpi_old_suspend_ordering();
 159	return 0;
 160}
 161
 162static int __init init_nvs_nosave(const struct dmi_system_id *d)
 163{
 164	acpi_nvs_nosave();
 165	return 0;
 166}
 167
 168bool acpi_sleep_default_s3;
 169
 170static int __init init_default_s3(const struct dmi_system_id *d)
 171{
 172	acpi_sleep_default_s3 = true;
 173	return 0;
 174}
 175
 176static const struct dmi_system_id acpisleep_dmi_table[] __initconst = {
 177	{
 178	.callback = init_old_suspend_ordering,
 179	.ident = "Abit KN9 (nForce4 variant)",
 180	.matches = {
 181		DMI_MATCH(DMI_BOARD_VENDOR, "http://www.abit.com.tw/"),
 182		DMI_MATCH(DMI_BOARD_NAME, "KN9 Series(NF-CK804)"),
 183		},
 184	},
 185	{
 186	.callback = init_old_suspend_ordering,
 187	.ident = "HP xw4600 Workstation",
 188	.matches = {
 189		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 190		DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
 191		},
 192	},
 193	{
 194	.callback = init_old_suspend_ordering,
 195	.ident = "Asus Pundit P1-AH2 (M2N8L motherboard)",
 196	.matches = {
 197		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTek Computer INC."),
 198		DMI_MATCH(DMI_BOARD_NAME, "M2N8L"),
 199		},
 200	},
 201	{
 202	.callback = init_old_suspend_ordering,
 203	.ident = "Panasonic CF51-2L",
 204	.matches = {
 205		DMI_MATCH(DMI_BOARD_VENDOR,
 206				"Matsushita Electric Industrial Co.,Ltd."),
 207		DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"),
 208		},
 209	},
 210	{
 211	.callback = init_nvs_nosave,
 212	.ident = "Sony Vaio VGN-FW41E_H",
 213	.matches = {
 214		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 215		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW41E_H"),
 216		},
 217	},
 218	{
 219	.callback = init_nvs_nosave,
 220	.ident = "Sony Vaio VGN-FW21E",
 221	.matches = {
 222		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 223		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21E"),
 224		},
 225	},
 226	{
 227	.callback = init_nvs_nosave,
 228	.ident = "Sony Vaio VGN-FW21M",
 229	.matches = {
 230		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 231		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW21M"),
 232		},
 233	},
 234	{
 235	.callback = init_nvs_nosave,
 236	.ident = "Sony Vaio VPCEB17FX",
 237	.matches = {
 238		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 239		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB17FX"),
 240		},
 241	},
 242	{
 243	.callback = init_nvs_nosave,
 244	.ident = "Sony Vaio VGN-SR11M",
 245	.matches = {
 246		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 247		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR11M"),
 248		},
 249	},
 250	{
 251	.callback = init_nvs_nosave,
 252	.ident = "Everex StepNote Series",
 253	.matches = {
 254		DMI_MATCH(DMI_SYS_VENDOR, "Everex Systems, Inc."),
 255		DMI_MATCH(DMI_PRODUCT_NAME, "Everex StepNote Series"),
 256		},
 257	},
 258	{
 259	.callback = init_nvs_nosave,
 260	.ident = "Sony Vaio VPCEB1Z1E",
 261	.matches = {
 262		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 263		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1Z1E"),
 264		},
 265	},
 266	{
 267	.callback = init_nvs_nosave,
 268	.ident = "Sony Vaio VGN-NW130D",
 269	.matches = {
 270		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 271		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-NW130D"),
 272		},
 273	},
 274	{
 275	.callback = init_nvs_nosave,
 276	.ident = "Sony Vaio VPCCW29FX",
 277	.matches = {
 278		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 279		DMI_MATCH(DMI_PRODUCT_NAME, "VPCCW29FX"),
 280		},
 281	},
 282	{
 283	.callback = init_nvs_nosave,
 284	.ident = "Averatec AV1020-ED2",
 285	.matches = {
 286		DMI_MATCH(DMI_SYS_VENDOR, "AVERATEC"),
 287		DMI_MATCH(DMI_PRODUCT_NAME, "1000 Series"),
 288		},
 289	},
 290	{
 291	.callback = init_old_suspend_ordering,
 292	.ident = "Asus A8N-SLI DELUXE",
 293	.matches = {
 294		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 295		DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI DELUXE"),
 296		},
 297	},
 298	{
 299	.callback = init_old_suspend_ordering,
 300	.ident = "Asus A8N-SLI Premium",
 301	.matches = {
 302		DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 303		DMI_MATCH(DMI_BOARD_NAME, "A8N-SLI Premium"),
 304		},
 305	},
 306	{
 307	.callback = init_nvs_nosave,
 308	.ident = "Sony Vaio VGN-SR26GN_P",
 309	.matches = {
 310		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 311		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-SR26GN_P"),
 312		},
 313	},
 314	{
 315	.callback = init_nvs_nosave,
 316	.ident = "Sony Vaio VPCEB1S1E",
 317	.matches = {
 318		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 319		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEB1S1E"),
 320		},
 321	},
 322	{
 323	.callback = init_nvs_nosave,
 324	.ident = "Sony Vaio VGN-FW520F",
 325	.matches = {
 326		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 327		DMI_MATCH(DMI_PRODUCT_NAME, "VGN-FW520F"),
 328		},
 329	},
 330	{
 331	.callback = init_nvs_nosave,
 332	.ident = "Asus K54C",
 333	.matches = {
 334		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 335		DMI_MATCH(DMI_PRODUCT_NAME, "K54C"),
 336		},
 337	},
 338	{
 339	.callback = init_nvs_nosave,
 340	.ident = "Asus K54HR",
 341	.matches = {
 342		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
 343		DMI_MATCH(DMI_PRODUCT_NAME, "K54HR"),
 344		},
 345	},
 346	{
 347	.callback = init_nvs_save_s3,
 348	.ident = "Asus 1025C",
 349	.matches = {
 350		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
 351		DMI_MATCH(DMI_PRODUCT_NAME, "1025C"),
 352		},
 353	},
 354	/*
 355	 * https://bugzilla.kernel.org/show_bug.cgi?id=189431
 356	 * Lenovo G50-45 is a platform later than 2012, but needs nvs memory
 357	 * saving during S3.
 358	 */
 359	{
 360	.callback = init_nvs_save_s3,
 361	.ident = "Lenovo G50-45",
 362	.matches = {
 363		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 364		DMI_MATCH(DMI_PRODUCT_NAME, "80E3"),
 365		},
 366	},
 367	{
 368	.callback = init_nvs_save_s3,
 369	.ident = "Lenovo G40-45",
 370	.matches = {
 371		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 372		DMI_MATCH(DMI_PRODUCT_NAME, "80E1"),
 373		},
 374	},
 375	/*
 376	 * ThinkPad X1 Tablet(2016) cannot do suspend-to-idle using
 377	 * the Low Power S0 Idle firmware interface (see
 378	 * https://bugzilla.kernel.org/show_bug.cgi?id=199057).
 379	 */
 380	{
 381	.callback = init_default_s3,
 382	.ident = "ThinkPad X1 Tablet(2016)",
 383	.matches = {
 384		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 385		DMI_MATCH(DMI_PRODUCT_NAME, "20GGA00L00"),
 386		},
 387	},
 388	{},
 389};
 390
 391static bool ignore_blacklist;
 392
 393void __init acpi_sleep_no_blacklist(void)
 394{
 395	ignore_blacklist = true;
 396}
 397
 398static void __init acpi_sleep_dmi_check(void)
 399{
 400	if (ignore_blacklist)
 401		return;
 402
 403	if (dmi_get_bios_year() >= 2012)
 404		acpi_nvs_nosave_s3();
 405
 406	dmi_check_system(acpisleep_dmi_table);
 407}
 408
 409/**
 410 * acpi_pm_freeze - Disable the GPEs and suspend EC transactions.
 411 */
 412static int acpi_pm_freeze(void)
 413{
 414	acpi_disable_all_gpes();
 415	acpi_os_wait_events_complete();
 416	acpi_ec_block_transactions();
 417	return 0;
 418}
 419
 420/**
 421 * acpi_pm_pre_suspend - Enable wakeup devices, "freeze" EC and save NVS.
 422 */
 423static int acpi_pm_pre_suspend(void)
 424{
 425	acpi_pm_freeze();
 426	return suspend_nvs_save();
 427}
 428
 429/**
 430 *	__acpi_pm_prepare - Prepare the platform to enter the target state.
 431 *
 432 *	If necessary, set the firmware waking vector and do arch-specific
 433 *	nastiness to get the wakeup code to the waking vector.
 434 */
 435static int __acpi_pm_prepare(void)
 436{
 437	int error = acpi_sleep_prepare(acpi_target_sleep_state);
 438	if (error)
 439		acpi_target_sleep_state = ACPI_STATE_S0;
 440
 441	return error;
 442}
 443
 444/**
 445 *	acpi_pm_prepare - Prepare the platform to enter the target sleep
 446 *		state and disable the GPEs.
 447 */
 448static int acpi_pm_prepare(void)
 449{
 450	int error = __acpi_pm_prepare();
 451	if (!error)
 452		error = acpi_pm_pre_suspend();
 453
 454	return error;
 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 acpi_device *pwr_btn_adev;
 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	pr_info("Waking up from system sleep state S%d\n", acpi_state);
 
 475	acpi_disable_wakeup_devices(acpi_state);
 476	acpi_leave_sleep_state(acpi_state);
 477
 478	/* reset firmware waking vector */
 479	acpi_set_waking_vector(0);
 480
 481	acpi_target_sleep_state = ACPI_STATE_S0;
 482
 483	acpi_resume_power_resources();
 484
 485	/* If we were woken with the fixed power button, provide a small
 486	 * hint to userspace in the form of a wakeup event on the fixed power
 487	 * button device (if it can be found).
 488	 *
 489	 * We delay the event generation til now, as the PM layer requires
 490	 * timekeeping to be running before we generate events. */
 491	if (!pwr_btn_event_pending)
 492		return;
 493
 494	pwr_btn_event_pending = false;
 495	pwr_btn_adev = acpi_dev_get_first_match_dev(ACPI_BUTTON_HID_POWERF,
 496						    NULL, -1);
 497	if (pwr_btn_adev) {
 498		pm_wakeup_event(&pwr_btn_adev->dev, 0);
 499		acpi_dev_put(pwr_btn_adev);
 500	}
 501}
 502
 503/**
 504 * acpi_pm_start - Start system PM transition.
 505 * @acpi_state: The target ACPI power state to transition to.
 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 sleep_no_lps0	(1)
 530#define acpi_target_sleep_state	ACPI_STATE_S0
 531#define acpi_sleep_default_s3	(1)
 532static inline void acpi_sleep_dmi_check(void) {}
 533#endif /* CONFIG_ACPI_SLEEP */
 534
 535#ifdef CONFIG_SUSPEND
 536static u32 acpi_suspend_states[] = {
 537	[PM_SUSPEND_ON] = ACPI_STATE_S0,
 538	[PM_SUSPEND_STANDBY] = ACPI_STATE_S1,
 539	[PM_SUSPEND_MEM] = ACPI_STATE_S3,
 540	[PM_SUSPEND_MAX] = ACPI_STATE_S5
 541};
 542
 543/**
 544 * acpi_suspend_begin - Set the target system sleep state to the state
 545 *	associated with given @pm_state, if supported.
 546 * @pm_state: The target system power management state.
 547 */
 548static int acpi_suspend_begin(suspend_state_t pm_state)
 549{
 550	u32 acpi_state = acpi_suspend_states[pm_state];
 551	int error;
 552
 553	error = (nvs_nosave || nvs_nosave_s3) ? 0 : suspend_nvs_alloc();
 554	if (error)
 555		return error;
 556
 557	if (!sleep_states[acpi_state]) {
 558		pr_err("ACPI does not support sleep state S%u\n", acpi_state);
 559		return -ENOSYS;
 
 
 
 
 560	}
 561	if (acpi_state > ACPI_STATE_S1)
 562		pm_set_suspend_via_firmware();
 563
 564	acpi_pm_start(acpi_state);
 565	return 0;
 566}
 567
 568/**
 569 *	acpi_suspend_enter - Actually enter a sleep state.
 570 *	@pm_state: ignored
 571 *
 572 *	Flush caches and go to sleep. For STR we have to call arch-specific
 573 *	assembly, which in turn call acpi_enter_sleep_state().
 574 *	It's unfortunate, but it works. Please fix if you're feeling frisky.
 575 */
 576static int acpi_suspend_enter(suspend_state_t pm_state)
 577{
 578	acpi_status status = AE_OK;
 579	u32 acpi_state = acpi_target_sleep_state;
 580	int error;
 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("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 all GPE and clear their status bits before interrupts are
 630	 * enabled. Some GPEs (like wakeup GPEs) have no handlers and this can
 631	 * prevent them from producing spurious interrups.
 632	 *
 633	 * acpi_leave_sleep_state() will reenable specific GPEs later.
 634	 *
 635	 * Because this code runs on one CPU with disabled interrupts (all of
 636	 * the other CPUs are offline at this time), it need not acquire any
 637	 * sleeping locks which may trigger an implicit preemption point even
 638	 * if there is no contention, so avoid doing that by using a low-level
 639	 * library routine here.
 640	 */
 641	acpi_hw_disable_all_gpes();
 642	/* Allow EC transactions to happen. */
 643	acpi_ec_unblock_transactions();
 644
 645	suspend_nvs_restore();
 646
 647	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 648}
 649
 650static int acpi_suspend_state_valid(suspend_state_t pm_state)
 651{
 652	u32 acpi_state;
 653
 654	switch (pm_state) {
 655	case PM_SUSPEND_ON:
 656	case PM_SUSPEND_STANDBY:
 657	case PM_SUSPEND_MEM:
 658		acpi_state = acpi_suspend_states[pm_state];
 659
 660		return sleep_states[acpi_state];
 661	default:
 662		return 0;
 663	}
 664}
 665
 666static const struct platform_suspend_ops acpi_suspend_ops = {
 667	.valid = acpi_suspend_state_valid,
 668	.begin = acpi_suspend_begin,
 669	.prepare_late = acpi_pm_prepare,
 670	.enter = acpi_suspend_enter,
 671	.wake = acpi_pm_finish,
 672	.end = acpi_pm_end,
 673};
 674
 675/**
 676 * acpi_suspend_begin_old - Set the target system sleep state to the
 677 *	state associated with given @pm_state, if supported, and
 678 *	execute the _PTS control method.  This function is used if the
 679 *	pre-ACPI 2.0 suspend ordering has been requested.
 680 * @pm_state: The target suspend state for the system.
 681 */
 682static int acpi_suspend_begin_old(suspend_state_t pm_state)
 683{
 684	int error = acpi_suspend_begin(pm_state);
 685	if (!error)
 686		error = __acpi_pm_prepare();
 687
 688	return error;
 689}
 690
 691/*
 692 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
 693 * been requested.
 694 */
 695static const struct platform_suspend_ops acpi_suspend_ops_old = {
 696	.valid = acpi_suspend_state_valid,
 697	.begin = acpi_suspend_begin_old,
 698	.prepare_late = acpi_pm_pre_suspend,
 699	.enter = acpi_suspend_enter,
 700	.wake = acpi_pm_finish,
 701	.end = acpi_pm_end,
 702	.recover = acpi_pm_finish,
 703};
 704
 705static bool s2idle_wakeup;
 706
 707int acpi_s2idle_begin(void)
 708{
 709	acpi_scan_lock_acquire();
 710	return 0;
 711}
 712
 713int acpi_s2idle_prepare(void)
 714{
 715	if (acpi_sci_irq_valid()) {
 716		int error;
 717
 718		error = enable_irq_wake(acpi_sci_irq);
 719		if (error)
 720			pr_warn("Warning: Failed to enable wakeup from IRQ %d: %d\n",
 721				acpi_sci_irq, error);
 722
 723		acpi_ec_set_gpe_wake_mask(ACPI_GPE_ENABLE);
 724	}
 725
 726	acpi_enable_wakeup_devices(ACPI_STATE_S0);
 727
 728	/* Change the configuration of GPEs to avoid spurious wakeup. */
 729	acpi_enable_all_wakeup_gpes();
 730	acpi_os_wait_events_complete();
 731
 732	s2idle_wakeup = true;
 733	return 0;
 734}
 735
 736bool acpi_s2idle_wake(void)
 737{
 738	if (!acpi_sci_irq_valid())
 739		return pm_wakeup_pending();
 740
 741	while (pm_wakeup_pending()) {
 742		/*
 743		 * If IRQD_WAKEUP_ARMED is set for the SCI at this point, the
 744		 * SCI has not triggered while suspended, so bail out (the
 745		 * wakeup is pending anyway and the SCI is not the source of
 746		 * it).
 747		 */
 748		if (irqd_is_wakeup_armed(irq_get_irq_data(acpi_sci_irq))) {
 749			pm_pr_dbg("Wakeup unrelated to ACPI SCI\n");
 750			return true;
 751		}
 752
 753		/*
 754		 * If the status bit of any enabled fixed event is set, the
 755		 * wakeup is regarded as valid.
 756		 */
 757		if (acpi_any_fixed_event_status_set()) {
 758			pm_pr_dbg("ACPI fixed event wakeup\n");
 759			return true;
 760		}
 761
 762		/* Check wakeups from drivers sharing the SCI. */
 763		if (acpi_check_wakeup_handlers()) {
 764			pm_pr_dbg("ACPI custom handler wakeup\n");
 765			return true;
 766		}
 767
 768		/*
 769		 * Check non-EC GPE wakeups and if there are none, cancel the
 770		 * SCI-related wakeup and dispatch the EC GPE.
 771		 */
 772		if (acpi_ec_dispatch_gpe()) {
 773			pm_pr_dbg("ACPI non-EC GPE wakeup\n");
 774			return true;
 775		}
 776
 777		acpi_os_wait_events_complete();
 778
 779		/*
 780		 * The SCI is in the "suspended" state now and it cannot produce
 781		 * new wakeup events till the rearming below, so if any of them
 782		 * are pending here, they must be resulting from the processing
 783		 * of EC events above or coming from somewhere else.
 784		 */
 785		if (pm_wakeup_pending()) {
 786			pm_pr_dbg("Wakeup after ACPI Notify sync\n");
 787			return true;
 788		}
 789
 790		pm_pr_dbg("Rearming ACPI SCI for wakeup\n");
 791
 792		pm_wakeup_clear(acpi_sci_irq);
 793		rearm_wake_irq(acpi_sci_irq);
 794	}
 795
 796	return false;
 797}
 798
 799void acpi_s2idle_restore(void)
 800{
 801	/*
 802	 * Drain pending events before restoring the working-state configuration
 803	 * of GPEs.
 804	 */
 805	acpi_os_wait_events_complete(); /* synchronize GPE processing */
 806	acpi_ec_flush_work(); /* flush the EC driver's workqueues */
 807	acpi_os_wait_events_complete(); /* synchronize Notify handling */
 808
 809	s2idle_wakeup = false;
 810
 811	acpi_enable_all_runtime_gpes();
 812
 813	acpi_disable_wakeup_devices(ACPI_STATE_S0);
 814
 815	if (acpi_sci_irq_valid()) {
 816		acpi_ec_set_gpe_wake_mask(ACPI_GPE_DISABLE);
 817		disable_irq_wake(acpi_sci_irq);
 818	}
 819}
 820
 821void acpi_s2idle_end(void)
 822{
 823	acpi_scan_lock_release();
 824}
 825
 826static const struct platform_s2idle_ops acpi_s2idle_ops = {
 827	.begin = acpi_s2idle_begin,
 828	.prepare = acpi_s2idle_prepare,
 829	.wake = acpi_s2idle_wake,
 830	.restore = acpi_s2idle_restore,
 831	.end = acpi_s2idle_end,
 832};
 
 833
 834void __weak acpi_s2idle_setup(void)
 835{
 836	if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
 837		pr_info("Efficient low-power S0 idle declared\n");
 838
 839	s2idle_set_ops(&acpi_s2idle_ops);
 840}
 841
 842static void __init acpi_sleep_suspend_setup(void)
 843{
 844	bool suspend_ops_needed = false;
 845	int i;
 846
 847	for (i = ACPI_STATE_S1; i < ACPI_STATE_S4; i++)
 848		if (acpi_sleep_state_supported(i)) {
 849			sleep_states[i] = 1;
 850			suspend_ops_needed = true;
 851		}
 852
 853	if (suspend_ops_needed)
 854		suspend_set_ops(old_suspend_ordering ?
 855				&acpi_suspend_ops_old : &acpi_suspend_ops);
 856
 857	acpi_s2idle_setup();
 858}
 859
 860#else /* !CONFIG_SUSPEND */
 861#define s2idle_wakeup		(false)
 862static inline void acpi_sleep_suspend_setup(void) {}
 863#endif /* !CONFIG_SUSPEND */
 864
 865bool acpi_s2idle_wakeup(void)
 866{
 867	return s2idle_wakeup;
 868}
 869
 870#ifdef CONFIG_PM_SLEEP
 871static u32 saved_bm_rld;
 872
 873static int  acpi_save_bm_rld(void)
 874{
 875	acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &saved_bm_rld);
 876	return 0;
 877}
 878
 879static void  acpi_restore_bm_rld(void)
 880{
 881	u32 resumed_bm_rld = 0;
 882
 883	acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_RLD, &resumed_bm_rld);
 884	if (resumed_bm_rld == saved_bm_rld)
 885		return;
 886
 887	acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, saved_bm_rld);
 888}
 889
 890static struct syscore_ops acpi_sleep_syscore_ops = {
 891	.suspend = acpi_save_bm_rld,
 892	.resume = acpi_restore_bm_rld,
 893};
 894
 895static void acpi_sleep_syscore_init(void)
 896{
 897	register_syscore_ops(&acpi_sleep_syscore_ops);
 898}
 899#else
 900static inline void acpi_sleep_syscore_init(void) {}
 901#endif /* CONFIG_PM_SLEEP */
 902
 903#ifdef CONFIG_HIBERNATION
 904static unsigned long s4_hardware_signature;
 905static struct acpi_table_facs *facs;
 906int acpi_check_s4_hw_signature = -1; /* Default behaviour is just to warn */
 907
 908static int acpi_hibernation_begin(pm_message_t stage)
 909{
 910	if (!nvs_nosave) {
 911		int error = suspend_nvs_alloc();
 912		if (error)
 913			return error;
 914	}
 915
 916	if (stage.event == PM_EVENT_HIBERNATE)
 917		pm_set_suspend_via_firmware();
 918
 919	acpi_pm_start(ACPI_STATE_S4);
 920	return 0;
 921}
 922
 923static int acpi_hibernation_enter(void)
 924{
 925	acpi_status status = AE_OK;
 926
 
 
 927	/* This shouldn't return.  If it returns, we have a problem */
 928	status = acpi_enter_sleep_state(ACPI_STATE_S4);
 929	/* Reprogram control registers */
 930	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 931
 932	return ACPI_SUCCESS(status) ? 0 : -EFAULT;
 933}
 934
 935static void acpi_hibernation_leave(void)
 936{
 937	pm_set_resume_via_firmware();
 938	/*
 939	 * If ACPI is not enabled by the BIOS and the boot kernel, we need to
 940	 * enable it here.
 941	 */
 942	acpi_enable();
 943	/* Reprogram control registers */
 944	acpi_leave_sleep_state_prep(ACPI_STATE_S4);
 945	/* Check the hardware signature */
 946	if (facs && s4_hardware_signature != facs->hardware_signature)
 947		pr_crit("Hardware changed while hibernated, success doubtful!\n");
 
 
 
 948	/* Restore the NVS memory area */
 949	suspend_nvs_restore();
 950	/* Allow EC transactions to happen. */
 951	acpi_ec_unblock_transactions();
 952}
 953
 954static void acpi_pm_thaw(void)
 955{
 956	acpi_ec_unblock_transactions();
 957	acpi_enable_all_runtime_gpes();
 958}
 959
 960static const struct platform_hibernation_ops acpi_hibernation_ops = {
 961	.begin = acpi_hibernation_begin,
 962	.end = acpi_pm_end,
 963	.pre_snapshot = acpi_pm_prepare,
 964	.finish = acpi_pm_finish,
 965	.prepare = acpi_pm_prepare,
 966	.enter = acpi_hibernation_enter,
 967	.leave = acpi_hibernation_leave,
 968	.pre_restore = acpi_pm_freeze,
 969	.restore_cleanup = acpi_pm_thaw,
 970};
 971
 972/**
 973 * acpi_hibernation_begin_old - Set the target system sleep state to
 974 *	ACPI_STATE_S4 and execute the _PTS control method.  This
 975 *	function is used if the pre-ACPI 2.0 suspend ordering has been
 976 *	requested.
 977 * @stage: The power management event message.
 978 */
 979static int acpi_hibernation_begin_old(pm_message_t stage)
 980{
 981	int error;
 982	/*
 983	 * The _TTS object should always be evaluated before the _PTS object.
 984	 * When the old_suspended_ordering is true, the _PTS object is
 985	 * evaluated in the acpi_sleep_prepare.
 986	 */
 987	acpi_sleep_tts_switch(ACPI_STATE_S4);
 988
 989	error = acpi_sleep_prepare(ACPI_STATE_S4);
 990	if (error)
 991		return error;
 992
 993	if (!nvs_nosave) {
 994		error = suspend_nvs_alloc();
 995		if (error)
 996			return error;
 
 997	}
 998
 999	if (stage.event == PM_EVENT_HIBERNATE)
1000		pm_set_suspend_via_firmware();
1001
1002	acpi_target_sleep_state = ACPI_STATE_S4;
1003	acpi_scan_lock_acquire();
1004	return 0;
1005}
1006
1007/*
1008 * The following callbacks are used if the pre-ACPI 2.0 suspend ordering has
1009 * been requested.
1010 */
1011static const struct platform_hibernation_ops acpi_hibernation_ops_old = {
1012	.begin = acpi_hibernation_begin_old,
1013	.end = acpi_pm_end,
1014	.pre_snapshot = acpi_pm_pre_suspend,
1015	.prepare = acpi_pm_freeze,
1016	.finish = acpi_pm_finish,
1017	.enter = acpi_hibernation_enter,
1018	.leave = acpi_hibernation_leave,
1019	.pre_restore = acpi_pm_freeze,
1020	.restore_cleanup = acpi_pm_thaw,
1021	.recover = acpi_pm_finish,
1022};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1023
1024static void acpi_sleep_hibernate_setup(void)
1025{
1026	if (!acpi_sleep_state_supported(ACPI_STATE_S4))
1027		return;
 
 
 
 
 
 
 
1028
1029	hibernation_set_ops(old_suspend_ordering ?
1030			&acpi_hibernation_ops_old : &acpi_hibernation_ops);
1031	sleep_states[ACPI_STATE_S4] = 1;
1032	if (!acpi_check_s4_hw_signature)
1033		return;
 
 
1034
1035	acpi_get_table(ACPI_SIG_FACS, 1, (struct acpi_table_header **)&facs);
1036	if (facs) {
1037		/*
1038		 * s4_hardware_signature is the local variable which is just
1039		 * used to warn about mismatch after we're attempting to
1040		 * resume (in violation of the ACPI specification.)
1041		 */
1042		s4_hardware_signature = facs->hardware_signature;
 
 
1043
1044		if (acpi_check_s4_hw_signature > 0) {
1045			/*
1046			 * If we're actually obeying the ACPI specification
1047			 * then the signature is written out as part of the
1048			 * swsusp header, in order to allow the boot kernel
1049			 * to gracefully decline to resume.
1050			 */
1051			swsusp_hardware_signature = facs->hardware_signature;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1052		}
1053	}
 
 
 
 
1054}
1055#else /* !CONFIG_HIBERNATION */
1056static inline void acpi_sleep_hibernate_setup(void) {}
1057#endif /* !CONFIG_HIBERNATION */
1058
1059static int acpi_power_off_prepare(struct sys_off_data *data)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1060{
1061	/* Prepare to power off the system */
1062	acpi_sleep_prepare(ACPI_STATE_S5);
1063	acpi_disable_all_gpes();
1064	acpi_os_wait_events_complete();
1065	return NOTIFY_DONE;
1066}
1067
1068static int acpi_power_off(struct sys_off_data *data)
1069{
1070	/* acpi_sleep_prepare(ACPI_STATE_S5) should have already been called */
1071	pr_debug("%s called\n", __func__);
1072	local_irq_disable();
1073	acpi_enter_sleep_state(ACPI_STATE_S5);
1074	return NOTIFY_DONE;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1075}
1076
1077int __init acpi_sleep_init(void)
1078{
1079	char supported[ACPI_S_STATE_COUNT * 3 + 1];
1080	char *pos = supported;
1081	int i;
 
 
 
 
1082
1083	acpi_sleep_dmi_check();
 
1084
1085	sleep_states[ACPI_STATE_S0] = 1;
 
1086
1087	acpi_sleep_syscore_init();
1088	acpi_sleep_suspend_setup();
1089	acpi_sleep_hibernate_setup();
 
 
 
 
 
1090
1091	if (acpi_sleep_state_supported(ACPI_STATE_S5)) {
1092		sleep_states[ACPI_STATE_S5] = 1;
 
1093
1094		register_sys_off_handler(SYS_OFF_MODE_POWER_OFF_PREPARE,
1095					 SYS_OFF_PRIO_FIRMWARE,
1096					 acpi_power_off_prepare, NULL);
1097
1098		register_sys_off_handler(SYS_OFF_MODE_POWER_OFF,
1099					 SYS_OFF_PRIO_FIRMWARE,
1100					 acpi_power_off, NULL);
1101
1102		/*
1103		 * Windows uses S5 for reboot, so some BIOSes depend on it to
1104		 * perform proper reboot.
1105		 */
1106		register_sys_off_handler(SYS_OFF_MODE_RESTART_PREPARE,
1107					 SYS_OFF_PRIO_FIRMWARE,
1108					 acpi_power_off_prepare, NULL);
1109	} else {
1110		acpi_no_s5 = true;
1111	}
1112
1113	supported[0] = 0;
1114	for (i = 0; i < ACPI_S_STATE_COUNT; i++) {
1115		if (sleep_states[i])
1116			pos += sprintf(pos, " S%d", i);
 
 
1117	}
1118	pr_info("(supports%s)\n", supported);
1119
1120	/*
1121	 * Register the tts_notifier to reboot notifier list so that the _TTS
1122	 * object can also be evaluated when the system enters S5.
1123	 */
1124	register_reboot_notifier(&tts_notifier);
 
1125	return 0;
1126}