xref: /openbmc/linux/drivers/acpi/device_pm.c (revision 236bdb88)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * drivers/acpi/device_pm.c - ACPI device power management routines.
4  *
5  * Copyright (C) 2012, Intel Corp.
6  * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11  */
12 
13 #define pr_fmt(fmt) "PM: " fmt
14 
15 #include <linux/acpi.h>
16 #include <linux/export.h>
17 #include <linux/mutex.h>
18 #include <linux/pm_qos.h>
19 #include <linux/pm_domain.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/suspend.h>
22 
23 #include "fan.h"
24 #include "internal.h"
25 
26 /**
27  * acpi_power_state_string - String representation of ACPI device power state.
28  * @state: ACPI device power state to return the string representation of.
29  */
30 const char *acpi_power_state_string(int state)
31 {
32 	switch (state) {
33 	case ACPI_STATE_D0:
34 		return "D0";
35 	case ACPI_STATE_D1:
36 		return "D1";
37 	case ACPI_STATE_D2:
38 		return "D2";
39 	case ACPI_STATE_D3_HOT:
40 		return "D3hot";
41 	case ACPI_STATE_D3_COLD:
42 		return "D3cold";
43 	default:
44 		return "(unknown)";
45 	}
46 }
47 
48 static int acpi_dev_pm_explicit_get(struct acpi_device *device, int *state)
49 {
50 	unsigned long long psc;
51 	acpi_status status;
52 
53 	status = acpi_evaluate_integer(device->handle, "_PSC", NULL, &psc);
54 	if (ACPI_FAILURE(status))
55 		return -ENODEV;
56 
57 	*state = psc;
58 	return 0;
59 }
60 
61 /**
62  * acpi_device_get_power - Get power state of an ACPI device.
63  * @device: Device to get the power state of.
64  * @state: Place to store the power state of the device.
65  *
66  * This function does not update the device's power.state field, but it may
67  * update its parent's power.state field (when the parent's power state is
68  * unknown and the device's power state turns out to be D0).
69  *
70  * Also, it does not update power resource reference counters to ensure that
71  * the power state returned by it will be persistent and it may return a power
72  * state shallower than previously set by acpi_device_set_power() for @device
73  * (if that power state depends on any power resources).
74  */
75 int acpi_device_get_power(struct acpi_device *device, int *state)
76 {
77 	int result = ACPI_STATE_UNKNOWN;
78 	struct acpi_device *parent;
79 	int error;
80 
81 	if (!device || !state)
82 		return -EINVAL;
83 
84 	parent = acpi_dev_parent(device);
85 
86 	if (!device->flags.power_manageable) {
87 		/* TBD: Non-recursive algorithm for walking up hierarchy. */
88 		*state = parent ? parent->power.state : ACPI_STATE_D0;
89 		goto out;
90 	}
91 
92 	/*
93 	 * Get the device's power state from power resources settings and _PSC,
94 	 * if available.
95 	 */
96 	if (device->power.flags.power_resources) {
97 		error = acpi_power_get_inferred_state(device, &result);
98 		if (error)
99 			return error;
100 	}
101 	if (device->power.flags.explicit_get) {
102 		int psc;
103 
104 		error = acpi_dev_pm_explicit_get(device, &psc);
105 		if (error)
106 			return error;
107 
108 		/*
109 		 * The power resources settings may indicate a power state
110 		 * shallower than the actual power state of the device, because
111 		 * the same power resources may be referenced by other devices.
112 		 *
113 		 * For systems predating ACPI 4.0 we assume that D3hot is the
114 		 * deepest state that can be supported.
115 		 */
116 		if (psc > result && psc < ACPI_STATE_D3_COLD)
117 			result = psc;
118 		else if (result == ACPI_STATE_UNKNOWN)
119 			result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
120 	}
121 
122 	/*
123 	 * If we were unsure about the device parent's power state up to this
124 	 * point, the fact that the device is in D0 implies that the parent has
125 	 * to be in D0 too, except if ignore_parent is set.
126 	 */
127 	if (!device->power.flags.ignore_parent && parent &&
128 	    parent->power.state == ACPI_STATE_UNKNOWN &&
129 	    result == ACPI_STATE_D0)
130 		parent->power.state = ACPI_STATE_D0;
131 
132 	*state = result;
133 
134  out:
135 	acpi_handle_debug(device->handle, "Power state: %s\n",
136 			  acpi_power_state_string(*state));
137 
138 	return 0;
139 }
140 
141 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
142 {
143 	if (adev->power.states[state].flags.explicit_set) {
144 		char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
145 		acpi_status status;
146 
147 		status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
148 		if (ACPI_FAILURE(status))
149 			return -ENODEV;
150 	}
151 	return 0;
152 }
153 
154 /**
155  * acpi_device_set_power - Set power state of an ACPI device.
156  * @device: Device to set the power state of.
157  * @state: New power state to set.
158  *
159  * Callers must ensure that the device is power manageable before using this
160  * function.
161  */
162 int acpi_device_set_power(struct acpi_device *device, int state)
163 {
164 	int target_state = state;
165 	int result = 0;
166 
167 	if (!device || !device->flags.power_manageable
168 	    || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
169 		return -EINVAL;
170 
171 	acpi_handle_debug(device->handle, "Power state change: %s -> %s\n",
172 			  acpi_power_state_string(device->power.state),
173 			  acpi_power_state_string(state));
174 
175 	/* Make sure this is a valid target state */
176 
177 	/* There is a special case for D0 addressed below. */
178 	if (state > ACPI_STATE_D0 && state == device->power.state)
179 		goto no_change;
180 
181 	if (state == ACPI_STATE_D3_COLD) {
182 		/*
183 		 * For transitions to D3cold we need to execute _PS3 and then
184 		 * possibly drop references to the power resources in use.
185 		 */
186 		state = ACPI_STATE_D3_HOT;
187 		/* If D3cold is not supported, use D3hot as the target state. */
188 		if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
189 			target_state = state;
190 	} else if (!device->power.states[state].flags.valid) {
191 		acpi_handle_debug(device->handle, "Power state %s not supported\n",
192 				  acpi_power_state_string(state));
193 		return -ENODEV;
194 	}
195 
196 	if (!device->power.flags.ignore_parent) {
197 		struct acpi_device *parent;
198 
199 		parent = acpi_dev_parent(device);
200 		if (parent && state < parent->power.state) {
201 			acpi_handle_debug(device->handle,
202 					  "Cannot transition to %s for parent in %s\n",
203 					  acpi_power_state_string(state),
204 					  acpi_power_state_string(parent->power.state));
205 			return -ENODEV;
206 		}
207 	}
208 
209 	/*
210 	 * Transition Power
211 	 * ----------------
212 	 * In accordance with ACPI 6, _PSx is executed before manipulating power
213 	 * resources, unless the target state is D0, in which case _PS0 is
214 	 * supposed to be executed after turning the power resources on.
215 	 */
216 	if (state > ACPI_STATE_D0) {
217 		/*
218 		 * According to ACPI 6, devices cannot go from lower-power
219 		 * (deeper) states to higher-power (shallower) states.
220 		 */
221 		if (state < device->power.state) {
222 			acpi_handle_debug(device->handle,
223 					  "Cannot transition from %s to %s\n",
224 					  acpi_power_state_string(device->power.state),
225 					  acpi_power_state_string(state));
226 			return -ENODEV;
227 		}
228 
229 		/*
230 		 * If the device goes from D3hot to D3cold, _PS3 has been
231 		 * evaluated for it already, so skip it in that case.
232 		 */
233 		if (device->power.state < ACPI_STATE_D3_HOT) {
234 			result = acpi_dev_pm_explicit_set(device, state);
235 			if (result)
236 				goto end;
237 		}
238 
239 		if (device->power.flags.power_resources)
240 			result = acpi_power_transition(device, target_state);
241 	} else {
242 		int cur_state = device->power.state;
243 
244 		if (device->power.flags.power_resources) {
245 			result = acpi_power_transition(device, ACPI_STATE_D0);
246 			if (result)
247 				goto end;
248 		}
249 
250 		if (cur_state == ACPI_STATE_D0) {
251 			int psc;
252 
253 			/* Nothing to do here if _PSC is not present. */
254 			if (!device->power.flags.explicit_get)
255 				goto no_change;
256 
257 			/*
258 			 * The power state of the device was set to D0 last
259 			 * time, but that might have happened before a
260 			 * system-wide transition involving the platform
261 			 * firmware, so it may be necessary to evaluate _PS0
262 			 * for the device here.  However, use extra care here
263 			 * and evaluate _PSC to check the device's current power
264 			 * state, and only invoke _PS0 if the evaluation of _PSC
265 			 * is successful and it returns a power state different
266 			 * from D0.
267 			 */
268 			result = acpi_dev_pm_explicit_get(device, &psc);
269 			if (result || psc == ACPI_STATE_D0)
270 				goto no_change;
271 		}
272 
273 		result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
274 	}
275 
276 end:
277 	if (result) {
278 		acpi_handle_debug(device->handle,
279 				  "Failed to change power state to %s\n",
280 				  acpi_power_state_string(target_state));
281 	} else {
282 		device->power.state = target_state;
283 		acpi_handle_debug(device->handle, "Power state changed to %s\n",
284 				  acpi_power_state_string(target_state));
285 	}
286 
287 	return result;
288 
289 no_change:
290 	acpi_handle_debug(device->handle, "Already in %s\n",
291 			  acpi_power_state_string(state));
292 	return 0;
293 }
294 EXPORT_SYMBOL(acpi_device_set_power);
295 
296 int acpi_bus_set_power(acpi_handle handle, int state)
297 {
298 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
299 
300 	if (device)
301 		return acpi_device_set_power(device, state);
302 
303 	return -ENODEV;
304 }
305 EXPORT_SYMBOL(acpi_bus_set_power);
306 
307 int acpi_bus_init_power(struct acpi_device *device)
308 {
309 	int state;
310 	int result;
311 
312 	if (!device)
313 		return -EINVAL;
314 
315 	device->power.state = ACPI_STATE_UNKNOWN;
316 	if (!acpi_device_is_present(device)) {
317 		device->flags.initialized = false;
318 		return -ENXIO;
319 	}
320 
321 	result = acpi_device_get_power(device, &state);
322 	if (result)
323 		return result;
324 
325 	if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
326 		/* Reference count the power resources. */
327 		result = acpi_power_on_resources(device, state);
328 		if (result)
329 			return result;
330 
331 		if (state == ACPI_STATE_D0) {
332 			/*
333 			 * If _PSC is not present and the state inferred from
334 			 * power resources appears to be D0, it still may be
335 			 * necessary to execute _PS0 at this point, because
336 			 * another device using the same power resources may
337 			 * have been put into D0 previously and that's why we
338 			 * see D0 here.
339 			 */
340 			result = acpi_dev_pm_explicit_set(device, state);
341 			if (result)
342 				return result;
343 		}
344 	} else if (state == ACPI_STATE_UNKNOWN) {
345 		/*
346 		 * No power resources and missing _PSC?  Cross fingers and make
347 		 * it D0 in hope that this is what the BIOS put the device into.
348 		 * [We tried to force D0 here by executing _PS0, but that broke
349 		 * Toshiba P870-303 in a nasty way.]
350 		 */
351 		state = ACPI_STATE_D0;
352 	}
353 	device->power.state = state;
354 	return 0;
355 }
356 
357 /**
358  * acpi_device_fix_up_power - Force device with missing _PSC into D0.
359  * @device: Device object whose power state is to be fixed up.
360  *
361  * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
362  * are assumed to be put into D0 by the BIOS.  However, in some cases that may
363  * not be the case and this function should be used then.
364  */
365 int acpi_device_fix_up_power(struct acpi_device *device)
366 {
367 	int ret = 0;
368 
369 	if (!device->power.flags.power_resources
370 	    && !device->power.flags.explicit_get
371 	    && device->power.state == ACPI_STATE_D0)
372 		ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
373 
374 	return ret;
375 }
376 EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);
377 
378 static int fix_up_power_if_applicable(struct acpi_device *adev, void *not_used)
379 {
380 	if (adev->status.present && adev->status.enabled)
381 		acpi_device_fix_up_power(adev);
382 
383 	return 0;
384 }
385 
386 /**
387  * acpi_device_fix_up_power_extended - Force device and its children into D0.
388  * @adev: Parent device object whose power state is to be fixed up.
389  *
390  * Call acpi_device_fix_up_power() for @adev and its children so long as they
391  * are reported as present and enabled.
392  */
393 void acpi_device_fix_up_power_extended(struct acpi_device *adev)
394 {
395 	acpi_device_fix_up_power(adev);
396 	acpi_dev_for_each_child(adev, fix_up_power_if_applicable, NULL);
397 }
398 EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_extended);
399 
400 int acpi_device_update_power(struct acpi_device *device, int *state_p)
401 {
402 	int state;
403 	int result;
404 
405 	if (device->power.state == ACPI_STATE_UNKNOWN) {
406 		result = acpi_bus_init_power(device);
407 		if (!result && state_p)
408 			*state_p = device->power.state;
409 
410 		return result;
411 	}
412 
413 	result = acpi_device_get_power(device, &state);
414 	if (result)
415 		return result;
416 
417 	if (state == ACPI_STATE_UNKNOWN) {
418 		state = ACPI_STATE_D0;
419 		result = acpi_device_set_power(device, state);
420 		if (result)
421 			return result;
422 	} else {
423 		if (device->power.flags.power_resources) {
424 			/*
425 			 * We don't need to really switch the state, bu we need
426 			 * to update the power resources' reference counters.
427 			 */
428 			result = acpi_power_transition(device, state);
429 			if (result)
430 				return result;
431 		}
432 		device->power.state = state;
433 	}
434 	if (state_p)
435 		*state_p = state;
436 
437 	return 0;
438 }
439 EXPORT_SYMBOL_GPL(acpi_device_update_power);
440 
441 int acpi_bus_update_power(acpi_handle handle, int *state_p)
442 {
443 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
444 
445 	if (device)
446 		return acpi_device_update_power(device, state_p);
447 
448 	return -ENODEV;
449 }
450 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
451 
452 bool acpi_bus_power_manageable(acpi_handle handle)
453 {
454 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
455 
456 	return device && device->flags.power_manageable;
457 }
458 EXPORT_SYMBOL(acpi_bus_power_manageable);
459 
460 static int acpi_power_up_if_adr_present(struct acpi_device *adev, void *not_used)
461 {
462 	if (!(adev->flags.power_manageable && adev->pnp.type.bus_address))
463 		return 0;
464 
465 	acpi_handle_debug(adev->handle, "Power state: %s\n",
466 			  acpi_power_state_string(adev->power.state));
467 
468 	if (adev->power.state == ACPI_STATE_D3_COLD)
469 		return acpi_device_set_power(adev, ACPI_STATE_D0);
470 
471 	return 0;
472 }
473 
474 /**
475  * acpi_dev_power_up_children_with_adr - Power up childres with valid _ADR
476  * @adev: Parent ACPI device object.
477  *
478  * Change the power states of the direct children of @adev that are in D3cold
479  * and hold valid _ADR objects to D0 in order to allow bus (e.g. PCI)
480  * enumeration code to access them.
481  */
482 void acpi_dev_power_up_children_with_adr(struct acpi_device *adev)
483 {
484 	acpi_dev_for_each_child(adev, acpi_power_up_if_adr_present, NULL);
485 }
486 
487 /**
488  * acpi_dev_power_state_for_wake - Deepest power state for wakeup signaling
489  * @adev: ACPI companion of the target device.
490  *
491  * Evaluate _S0W for @adev and return the value produced by it or return
492  * ACPI_STATE_UNKNOWN on errors (including _S0W not present).
493  */
494 u8 acpi_dev_power_state_for_wake(struct acpi_device *adev)
495 {
496 	unsigned long long state;
497 	acpi_status status;
498 
499 	status = acpi_evaluate_integer(adev->handle, "_S0W", NULL, &state);
500 	if (ACPI_FAILURE(status))
501 		return ACPI_STATE_UNKNOWN;
502 
503 	return state;
504 }
505 
506 #ifdef CONFIG_PM
507 static DEFINE_MUTEX(acpi_pm_notifier_lock);
508 static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
509 
510 void acpi_pm_wakeup_event(struct device *dev)
511 {
512 	pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
513 }
514 EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
515 
516 static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
517 {
518 	struct acpi_device *adev;
519 
520 	if (val != ACPI_NOTIFY_DEVICE_WAKE)
521 		return;
522 
523 	acpi_handle_debug(handle, "Wake notify\n");
524 
525 	adev = acpi_get_acpi_dev(handle);
526 	if (!adev)
527 		return;
528 
529 	mutex_lock(&acpi_pm_notifier_lock);
530 
531 	if (adev->wakeup.flags.notifier_present) {
532 		pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
533 		if (adev->wakeup.context.func) {
534 			acpi_handle_debug(handle, "Running %pS for %s\n",
535 					  adev->wakeup.context.func,
536 					  dev_name(adev->wakeup.context.dev));
537 			adev->wakeup.context.func(&adev->wakeup.context);
538 		}
539 	}
540 
541 	mutex_unlock(&acpi_pm_notifier_lock);
542 
543 	acpi_put_acpi_dev(adev);
544 }
545 
546 /**
547  * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
548  * @adev: ACPI device to add the notify handler for.
549  * @dev: Device to generate a wakeup event for while handling the notification.
550  * @func: Work function to execute when handling the notification.
551  *
552  * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
553  * PM wakeup events.  For example, wakeup events may be generated for bridges
554  * if one of the devices below the bridge is signaling wakeup, even if the
555  * bridge itself doesn't have a wakeup GPE associated with it.
556  */
557 acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
558 			void (*func)(struct acpi_device_wakeup_context *context))
559 {
560 	acpi_status status = AE_ALREADY_EXISTS;
561 
562 	if (!dev && !func)
563 		return AE_BAD_PARAMETER;
564 
565 	mutex_lock(&acpi_pm_notifier_install_lock);
566 
567 	if (adev->wakeup.flags.notifier_present)
568 		goto out;
569 
570 	status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
571 					     acpi_pm_notify_handler, NULL);
572 	if (ACPI_FAILURE(status))
573 		goto out;
574 
575 	mutex_lock(&acpi_pm_notifier_lock);
576 	adev->wakeup.ws = wakeup_source_register(&adev->dev,
577 						 dev_name(&adev->dev));
578 	adev->wakeup.context.dev = dev;
579 	adev->wakeup.context.func = func;
580 	adev->wakeup.flags.notifier_present = true;
581 	mutex_unlock(&acpi_pm_notifier_lock);
582 
583  out:
584 	mutex_unlock(&acpi_pm_notifier_install_lock);
585 	return status;
586 }
587 
588 /**
589  * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
590  * @adev: ACPI device to remove the notifier from.
591  */
592 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
593 {
594 	acpi_status status = AE_BAD_PARAMETER;
595 
596 	mutex_lock(&acpi_pm_notifier_install_lock);
597 
598 	if (!adev->wakeup.flags.notifier_present)
599 		goto out;
600 
601 	status = acpi_remove_notify_handler(adev->handle,
602 					    ACPI_SYSTEM_NOTIFY,
603 					    acpi_pm_notify_handler);
604 	if (ACPI_FAILURE(status))
605 		goto out;
606 
607 	mutex_lock(&acpi_pm_notifier_lock);
608 	adev->wakeup.context.func = NULL;
609 	adev->wakeup.context.dev = NULL;
610 	wakeup_source_unregister(adev->wakeup.ws);
611 	adev->wakeup.flags.notifier_present = false;
612 	mutex_unlock(&acpi_pm_notifier_lock);
613 
614  out:
615 	mutex_unlock(&acpi_pm_notifier_install_lock);
616 	return status;
617 }
618 
619 bool acpi_bus_can_wakeup(acpi_handle handle)
620 {
621 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
622 
623 	return device && device->wakeup.flags.valid;
624 }
625 EXPORT_SYMBOL(acpi_bus_can_wakeup);
626 
627 bool acpi_pm_device_can_wakeup(struct device *dev)
628 {
629 	struct acpi_device *adev = ACPI_COMPANION(dev);
630 
631 	return adev ? acpi_device_can_wakeup(adev) : false;
632 }
633 
634 /**
635  * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
636  * @dev: Device whose preferred target power state to return.
637  * @adev: ACPI device node corresponding to @dev.
638  * @target_state: System state to match the resultant device state.
639  * @d_min_p: Location to store the highest power state available to the device.
640  * @d_max_p: Location to store the lowest power state available to the device.
641  *
642  * Find the lowest power (highest number) and highest power (lowest number) ACPI
643  * device power states that the device can be in while the system is in the
644  * state represented by @target_state.  Store the integer numbers representing
645  * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
646  * respectively.
647  *
648  * Callers must ensure that @dev and @adev are valid pointers and that @adev
649  * actually corresponds to @dev before using this function.
650  *
651  * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
652  * returns a value that doesn't make sense.  The memory locations pointed to by
653  * @d_max_p and @d_min_p are only modified on success.
654  */
655 static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
656 				 u32 target_state, int *d_min_p, int *d_max_p)
657 {
658 	char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
659 	acpi_handle handle = adev->handle;
660 	unsigned long long ret;
661 	int d_min, d_max;
662 	bool wakeup = false;
663 	bool has_sxd = false;
664 	acpi_status status;
665 
666 	/*
667 	 * If the system state is S0, the lowest power state the device can be
668 	 * in is D3cold, unless the device has _S0W and is supposed to signal
669 	 * wakeup, in which case the return value of _S0W has to be used as the
670 	 * lowest power state available to the device.
671 	 */
672 	d_min = ACPI_STATE_D0;
673 	d_max = ACPI_STATE_D3_COLD;
674 
675 	/*
676 	 * If present, _SxD methods return the minimum D-state (highest power
677 	 * state) we can use for the corresponding S-states.  Otherwise, the
678 	 * minimum D-state is D0 (ACPI 3.x).
679 	 */
680 	if (target_state > ACPI_STATE_S0) {
681 		/*
682 		 * We rely on acpi_evaluate_integer() not clobbering the integer
683 		 * provided if AE_NOT_FOUND is returned.
684 		 */
685 		ret = d_min;
686 		status = acpi_evaluate_integer(handle, method, NULL, &ret);
687 		if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
688 		    || ret > ACPI_STATE_D3_COLD)
689 			return -ENODATA;
690 
691 		/*
692 		 * We need to handle legacy systems where D3hot and D3cold are
693 		 * the same and 3 is returned in both cases, so fall back to
694 		 * D3cold if D3hot is not a valid state.
695 		 */
696 		if (!adev->power.states[ret].flags.valid) {
697 			if (ret == ACPI_STATE_D3_HOT)
698 				ret = ACPI_STATE_D3_COLD;
699 			else
700 				return -ENODATA;
701 		}
702 
703 		if (status == AE_OK)
704 			has_sxd = true;
705 
706 		d_min = ret;
707 		wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
708 			&& adev->wakeup.sleep_state >= target_state;
709 	} else if (device_may_wakeup(dev) && dev->power.wakeirq) {
710 		/*
711 		 * The ACPI subsystem doesn't manage the wake bit for IRQs
712 		 * defined with ExclusiveAndWake and SharedAndWake. Instead we
713 		 * expect them to be managed via the PM subsystem. Drivers
714 		 * should call dev_pm_set_wake_irq to register an IRQ as a wake
715 		 * source.
716 		 *
717 		 * If a device has a wake IRQ attached we need to check the
718 		 * _S0W method to get the correct wake D-state. Otherwise we
719 		 * end up putting the device into D3Cold which will more than
720 		 * likely disable wake functionality.
721 		 */
722 		wakeup = true;
723 	} else {
724 		/* ACPI GPE is specified in _PRW. */
725 		wakeup = adev->wakeup.flags.valid;
726 	}
727 
728 	/*
729 	 * If _PRW says we can wake up the system from the target sleep state,
730 	 * the D-state returned by _SxD is sufficient for that (we assume a
731 	 * wakeup-aware driver if wake is set).  Still, if _SxW exists
732 	 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
733 	 * can wake the system.  _S0W may be valid, too.
734 	 */
735 	if (wakeup) {
736 		method[3] = 'W';
737 		status = acpi_evaluate_integer(handle, method, NULL, &ret);
738 		if (status == AE_NOT_FOUND) {
739 			/* No _SxW. In this case, the ACPI spec says that we
740 			 * must not go into any power state deeper than the
741 			 * value returned from _SxD.
742 			 */
743 			if (has_sxd && target_state > ACPI_STATE_S0)
744 				d_max = d_min;
745 		} else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
746 			/* Fall back to D3cold if ret is not a valid state. */
747 			if (!adev->power.states[ret].flags.valid)
748 				ret = ACPI_STATE_D3_COLD;
749 
750 			d_max = ret > d_min ? ret : d_min;
751 		} else {
752 			return -ENODATA;
753 		}
754 	}
755 
756 	if (d_min_p)
757 		*d_min_p = d_min;
758 
759 	if (d_max_p)
760 		*d_max_p = d_max;
761 
762 	return 0;
763 }
764 
765 /**
766  * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
767  * @dev: Device whose preferred target power state to return.
768  * @d_min_p: Location to store the upper limit of the allowed states range.
769  * @d_max_in: Deepest low-power state to take into consideration.
770  * Return value: Preferred power state of the device on success, -ENODEV
771  * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
772  * incorrect, or -ENODATA on ACPI method failure.
773  *
774  * The caller must ensure that @dev is valid before using this function.
775  */
776 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
777 {
778 	struct acpi_device *adev;
779 	int ret, d_min, d_max;
780 
781 	if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
782 		return -EINVAL;
783 
784 	if (d_max_in > ACPI_STATE_D2) {
785 		enum pm_qos_flags_status stat;
786 
787 		stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
788 		if (stat == PM_QOS_FLAGS_ALL)
789 			d_max_in = ACPI_STATE_D2;
790 	}
791 
792 	adev = ACPI_COMPANION(dev);
793 	if (!adev) {
794 		dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
795 		return -ENODEV;
796 	}
797 
798 	ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
799 				    &d_min, &d_max);
800 	if (ret)
801 		return ret;
802 
803 	if (d_max_in < d_min)
804 		return -EINVAL;
805 
806 	if (d_max > d_max_in) {
807 		for (d_max = d_max_in; d_max > d_min; d_max--) {
808 			if (adev->power.states[d_max].flags.valid)
809 				break;
810 		}
811 	}
812 
813 	if (d_min_p)
814 		*d_min_p = d_min;
815 
816 	return d_max;
817 }
818 EXPORT_SYMBOL(acpi_pm_device_sleep_state);
819 
820 /**
821  * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
822  * @context: Device wakeup context.
823  */
824 static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
825 {
826 	struct device *dev = context->dev;
827 
828 	if (dev) {
829 		pm_wakeup_event(dev, 0);
830 		pm_request_resume(dev);
831 	}
832 }
833 
834 static DEFINE_MUTEX(acpi_wakeup_lock);
835 
836 static int __acpi_device_wakeup_enable(struct acpi_device *adev,
837 				       u32 target_state)
838 {
839 	struct acpi_device_wakeup *wakeup = &adev->wakeup;
840 	acpi_status status;
841 	int error = 0;
842 
843 	mutex_lock(&acpi_wakeup_lock);
844 
845 	/*
846 	 * If the device wakeup power is already enabled, disable it and enable
847 	 * it again in case it depends on the configuration of subordinate
848 	 * devices and the conditions have changed since it was enabled last
849 	 * time.
850 	 */
851 	if (wakeup->enable_count > 0)
852 		acpi_disable_wakeup_device_power(adev);
853 
854 	error = acpi_enable_wakeup_device_power(adev, target_state);
855 	if (error) {
856 		if (wakeup->enable_count > 0) {
857 			acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
858 			wakeup->enable_count = 0;
859 		}
860 		goto out;
861 	}
862 
863 	if (wakeup->enable_count > 0)
864 		goto inc;
865 
866 	status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
867 	if (ACPI_FAILURE(status)) {
868 		acpi_disable_wakeup_device_power(adev);
869 		error = -EIO;
870 		goto out;
871 	}
872 
873 	acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",
874 			  (unsigned int)wakeup->gpe_number);
875 
876 inc:
877 	if (wakeup->enable_count < INT_MAX)
878 		wakeup->enable_count++;
879 	else
880 		acpi_handle_info(adev->handle, "Wakeup enable count out of bounds!\n");
881 
882 out:
883 	mutex_unlock(&acpi_wakeup_lock);
884 	return error;
885 }
886 
887 /**
888  * acpi_device_wakeup_enable - Enable wakeup functionality for device.
889  * @adev: ACPI device to enable wakeup functionality for.
890  * @target_state: State the system is transitioning into.
891  *
892  * Enable the GPE associated with @adev so that it can generate wakeup signals
893  * for the device in response to external (remote) events and enable wakeup
894  * power for it.
895  *
896  * Callers must ensure that @adev is a valid ACPI device node before executing
897  * this function.
898  */
899 static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
900 {
901 	return __acpi_device_wakeup_enable(adev, target_state);
902 }
903 
904 /**
905  * acpi_device_wakeup_disable - Disable wakeup functionality for device.
906  * @adev: ACPI device to disable wakeup functionality for.
907  *
908  * Disable the GPE associated with @adev and disable wakeup power for it.
909  *
910  * Callers must ensure that @adev is a valid ACPI device node before executing
911  * this function.
912  */
913 static void acpi_device_wakeup_disable(struct acpi_device *adev)
914 {
915 	struct acpi_device_wakeup *wakeup = &adev->wakeup;
916 
917 	mutex_lock(&acpi_wakeup_lock);
918 
919 	if (!wakeup->enable_count)
920 		goto out;
921 
922 	acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
923 	acpi_disable_wakeup_device_power(adev);
924 
925 	wakeup->enable_count--;
926 
927 out:
928 	mutex_unlock(&acpi_wakeup_lock);
929 }
930 
931 /**
932  * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
933  * @dev: Device to enable/disable to generate wakeup events.
934  * @enable: Whether to enable or disable the wakeup functionality.
935  */
936 int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
937 {
938 	struct acpi_device *adev;
939 	int error;
940 
941 	adev = ACPI_COMPANION(dev);
942 	if (!adev) {
943 		dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
944 		return -ENODEV;
945 	}
946 
947 	if (!acpi_device_can_wakeup(adev))
948 		return -EINVAL;
949 
950 	if (!enable) {
951 		acpi_device_wakeup_disable(adev);
952 		dev_dbg(dev, "Wakeup disabled by ACPI\n");
953 		return 0;
954 	}
955 
956 	error = __acpi_device_wakeup_enable(adev, acpi_target_system_state());
957 	if (!error)
958 		dev_dbg(dev, "Wakeup enabled by ACPI\n");
959 
960 	return error;
961 }
962 EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
963 
964 /**
965  * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
966  * @dev: Device to put into a low-power state.
967  * @adev: ACPI device node corresponding to @dev.
968  * @system_state: System state to choose the device state for.
969  */
970 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
971 				 u32 system_state)
972 {
973 	int ret, state;
974 
975 	if (!acpi_device_power_manageable(adev))
976 		return 0;
977 
978 	ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
979 	return ret ? ret : acpi_device_set_power(adev, state);
980 }
981 
982 /**
983  * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
984  * @adev: ACPI device node to put into the full-power state.
985  */
986 static int acpi_dev_pm_full_power(struct acpi_device *adev)
987 {
988 	return acpi_device_power_manageable(adev) ?
989 		acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
990 }
991 
992 /**
993  * acpi_dev_suspend - Put device into a low-power state using ACPI.
994  * @dev: Device to put into a low-power state.
995  * @wakeup: Whether or not to enable wakeup for the device.
996  *
997  * Put the given device into a low-power state using the standard ACPI
998  * mechanism.  Set up remote wakeup if desired, choose the state to put the
999  * device into (this checks if remote wakeup is expected to work too), and set
1000  * the power state of the device.
1001  */
1002 int acpi_dev_suspend(struct device *dev, bool wakeup)
1003 {
1004 	struct acpi_device *adev = ACPI_COMPANION(dev);
1005 	u32 target_state = acpi_target_system_state();
1006 	int error;
1007 
1008 	if (!adev)
1009 		return 0;
1010 
1011 	if (wakeup && acpi_device_can_wakeup(adev)) {
1012 		error = acpi_device_wakeup_enable(adev, target_state);
1013 		if (error)
1014 			return -EAGAIN;
1015 	} else {
1016 		wakeup = false;
1017 	}
1018 
1019 	error = acpi_dev_pm_low_power(dev, adev, target_state);
1020 	if (error && wakeup)
1021 		acpi_device_wakeup_disable(adev);
1022 
1023 	return error;
1024 }
1025 EXPORT_SYMBOL_GPL(acpi_dev_suspend);
1026 
1027 /**
1028  * acpi_dev_resume - Put device into the full-power state using ACPI.
1029  * @dev: Device to put into the full-power state.
1030  *
1031  * Put the given device into the full-power state using the standard ACPI
1032  * mechanism.  Set the power state of the device to ACPI D0 and disable wakeup.
1033  */
1034 int acpi_dev_resume(struct device *dev)
1035 {
1036 	struct acpi_device *adev = ACPI_COMPANION(dev);
1037 	int error;
1038 
1039 	if (!adev)
1040 		return 0;
1041 
1042 	error = acpi_dev_pm_full_power(adev);
1043 	acpi_device_wakeup_disable(adev);
1044 	return error;
1045 }
1046 EXPORT_SYMBOL_GPL(acpi_dev_resume);
1047 
1048 /**
1049  * acpi_subsys_runtime_suspend - Suspend device using ACPI.
1050  * @dev: Device to suspend.
1051  *
1052  * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
1053  * it into a runtime low-power state.
1054  */
1055 int acpi_subsys_runtime_suspend(struct device *dev)
1056 {
1057 	int ret = pm_generic_runtime_suspend(dev);
1058 
1059 	return ret ? ret : acpi_dev_suspend(dev, true);
1060 }
1061 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
1062 
1063 /**
1064  * acpi_subsys_runtime_resume - Resume device using ACPI.
1065  * @dev: Device to Resume.
1066  *
1067  * Use ACPI to put the given device into the full-power state and carry out the
1068  * generic runtime resume procedure for it.
1069  */
1070 int acpi_subsys_runtime_resume(struct device *dev)
1071 {
1072 	int ret = acpi_dev_resume(dev);
1073 
1074 	return ret ? ret : pm_generic_runtime_resume(dev);
1075 }
1076 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
1077 
1078 #ifdef CONFIG_PM_SLEEP
1079 static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
1080 {
1081 	u32 sys_target = acpi_target_system_state();
1082 	int ret, state;
1083 
1084 	if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&
1085 	    device_may_wakeup(dev) != !!adev->wakeup.prepare_count))
1086 		return true;
1087 
1088 	if (sys_target == ACPI_STATE_S0)
1089 		return false;
1090 
1091 	if (adev->power.flags.dsw_present)
1092 		return true;
1093 
1094 	ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
1095 	if (ret)
1096 		return true;
1097 
1098 	return state != adev->power.state;
1099 }
1100 
1101 /**
1102  * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
1103  * @dev: Device to prepare.
1104  */
1105 int acpi_subsys_prepare(struct device *dev)
1106 {
1107 	struct acpi_device *adev = ACPI_COMPANION(dev);
1108 
1109 	if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
1110 		int ret = dev->driver->pm->prepare(dev);
1111 
1112 		if (ret < 0)
1113 			return ret;
1114 
1115 		if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
1116 			return 0;
1117 	}
1118 
1119 	return !acpi_dev_needs_resume(dev, adev);
1120 }
1121 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
1122 
1123 /**
1124  * acpi_subsys_complete - Finalize device's resume during system resume.
1125  * @dev: Device to handle.
1126  */
1127 void acpi_subsys_complete(struct device *dev)
1128 {
1129 	pm_generic_complete(dev);
1130 	/*
1131 	 * If the device had been runtime-suspended before the system went into
1132 	 * the sleep state it is going out of and it has never been resumed till
1133 	 * now, resume it in case the firmware powered it up.
1134 	 */
1135 	if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
1136 		pm_request_resume(dev);
1137 }
1138 EXPORT_SYMBOL_GPL(acpi_subsys_complete);
1139 
1140 /**
1141  * acpi_subsys_suspend - Run the device driver's suspend callback.
1142  * @dev: Device to handle.
1143  *
1144  * Follow PCI and resume devices from runtime suspend before running their
1145  * system suspend callbacks, unless the driver can cope with runtime-suspended
1146  * devices during system suspend and there are no ACPI-specific reasons for
1147  * resuming them.
1148  */
1149 int acpi_subsys_suspend(struct device *dev)
1150 {
1151 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1152 	    acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1153 		pm_runtime_resume(dev);
1154 
1155 	return pm_generic_suspend(dev);
1156 }
1157 EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
1158 
1159 /**
1160  * acpi_subsys_suspend_late - Suspend device using ACPI.
1161  * @dev: Device to suspend.
1162  *
1163  * Carry out the generic late suspend procedure for @dev and use ACPI to put
1164  * it into a low-power state during system transition into a sleep state.
1165  */
1166 int acpi_subsys_suspend_late(struct device *dev)
1167 {
1168 	int ret;
1169 
1170 	if (dev_pm_skip_suspend(dev))
1171 		return 0;
1172 
1173 	ret = pm_generic_suspend_late(dev);
1174 	return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
1175 }
1176 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
1177 
1178 /**
1179  * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
1180  * @dev: Device to suspend.
1181  */
1182 int acpi_subsys_suspend_noirq(struct device *dev)
1183 {
1184 	int ret;
1185 
1186 	if (dev_pm_skip_suspend(dev))
1187 		return 0;
1188 
1189 	ret = pm_generic_suspend_noirq(dev);
1190 	if (ret)
1191 		return ret;
1192 
1193 	/*
1194 	 * If the target system sleep state is suspend-to-idle, it is sufficient
1195 	 * to check whether or not the device's wakeup settings are good for
1196 	 * runtime PM.  Otherwise, the pm_resume_via_firmware() check will cause
1197 	 * acpi_subsys_complete() to take care of fixing up the device's state
1198 	 * anyway, if need be.
1199 	 */
1200 	if (device_can_wakeup(dev) && !device_may_wakeup(dev))
1201 		dev->power.may_skip_resume = false;
1202 
1203 	return 0;
1204 }
1205 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
1206 
1207 /**
1208  * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
1209  * @dev: Device to handle.
1210  */
1211 static int acpi_subsys_resume_noirq(struct device *dev)
1212 {
1213 	if (dev_pm_skip_resume(dev))
1214 		return 0;
1215 
1216 	return pm_generic_resume_noirq(dev);
1217 }
1218 
1219 /**
1220  * acpi_subsys_resume_early - Resume device using ACPI.
1221  * @dev: Device to Resume.
1222  *
1223  * Use ACPI to put the given device into the full-power state and carry out the
1224  * generic early resume procedure for it during system transition into the
1225  * working state, but only do that if device either defines early resume
1226  * handler, or does not define power operations at all. Otherwise powering up
1227  * of the device is postponed to the normal resume phase.
1228  */
1229 static int acpi_subsys_resume_early(struct device *dev)
1230 {
1231 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1232 	int ret;
1233 
1234 	if (dev_pm_skip_resume(dev))
1235 		return 0;
1236 
1237 	if (pm && !pm->resume_early) {
1238 		dev_dbg(dev, "postponing D0 transition to normal resume stage\n");
1239 		return 0;
1240 	}
1241 
1242 	ret = acpi_dev_resume(dev);
1243 	return ret ? ret : pm_generic_resume_early(dev);
1244 }
1245 
1246 /**
1247  * acpi_subsys_resume - Resume device using ACPI.
1248  * @dev: Device to Resume.
1249  *
1250  * Use ACPI to put the given device into the full-power state if it has not been
1251  * powered up during early resume phase, and carry out the generic resume
1252  * procedure for it during system transition into the working state.
1253  */
1254 static int acpi_subsys_resume(struct device *dev)
1255 {
1256 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1257 	int ret = 0;
1258 
1259 	if (!dev_pm_skip_resume(dev) && pm && !pm->resume_early) {
1260 		dev_dbg(dev, "executing postponed D0 transition\n");
1261 		ret = acpi_dev_resume(dev);
1262 	}
1263 
1264 	return ret ? ret : pm_generic_resume(dev);
1265 }
1266 
1267 /**
1268  * acpi_subsys_freeze - Run the device driver's freeze callback.
1269  * @dev: Device to handle.
1270  */
1271 int acpi_subsys_freeze(struct device *dev)
1272 {
1273 	/*
1274 	 * Resume all runtime-suspended devices before creating a snapshot
1275 	 * image of system memory, because the restore kernel generally cannot
1276 	 * be expected to always handle them consistently and they need to be
1277 	 * put into the runtime-active metastate during system resume anyway,
1278 	 * so it is better to ensure that the state saved in the image will be
1279 	 * always consistent with that.
1280 	 */
1281 	pm_runtime_resume(dev);
1282 
1283 	return pm_generic_freeze(dev);
1284 }
1285 EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1286 
1287 /**
1288  * acpi_subsys_restore_early - Restore device using ACPI.
1289  * @dev: Device to restore.
1290  */
1291 int acpi_subsys_restore_early(struct device *dev)
1292 {
1293 	int ret = acpi_dev_resume(dev);
1294 
1295 	return ret ? ret : pm_generic_restore_early(dev);
1296 }
1297 EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);
1298 
1299 /**
1300  * acpi_subsys_poweroff - Run the device driver's poweroff callback.
1301  * @dev: Device to handle.
1302  *
1303  * Follow PCI and resume devices from runtime suspend before running their
1304  * system poweroff callbacks, unless the driver can cope with runtime-suspended
1305  * devices during system suspend and there are no ACPI-specific reasons for
1306  * resuming them.
1307  */
1308 int acpi_subsys_poweroff(struct device *dev)
1309 {
1310 	if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1311 	    acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1312 		pm_runtime_resume(dev);
1313 
1314 	return pm_generic_poweroff(dev);
1315 }
1316 EXPORT_SYMBOL_GPL(acpi_subsys_poweroff);
1317 
1318 /**
1319  * acpi_subsys_poweroff_late - Run the device driver's poweroff callback.
1320  * @dev: Device to handle.
1321  *
1322  * Carry out the generic late poweroff procedure for @dev and use ACPI to put
1323  * it into a low-power state during system transition into a sleep state.
1324  */
1325 static int acpi_subsys_poweroff_late(struct device *dev)
1326 {
1327 	int ret;
1328 
1329 	if (dev_pm_skip_suspend(dev))
1330 		return 0;
1331 
1332 	ret = pm_generic_poweroff_late(dev);
1333 	if (ret)
1334 		return ret;
1335 
1336 	return acpi_dev_suspend(dev, device_may_wakeup(dev));
1337 }
1338 
1339 /**
1340  * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.
1341  * @dev: Device to suspend.
1342  */
1343 static int acpi_subsys_poweroff_noirq(struct device *dev)
1344 {
1345 	if (dev_pm_skip_suspend(dev))
1346 		return 0;
1347 
1348 	return pm_generic_poweroff_noirq(dev);
1349 }
1350 #endif /* CONFIG_PM_SLEEP */
1351 
1352 static struct dev_pm_domain acpi_general_pm_domain = {
1353 	.ops = {
1354 		.runtime_suspend = acpi_subsys_runtime_suspend,
1355 		.runtime_resume = acpi_subsys_runtime_resume,
1356 #ifdef CONFIG_PM_SLEEP
1357 		.prepare = acpi_subsys_prepare,
1358 		.complete = acpi_subsys_complete,
1359 		.suspend = acpi_subsys_suspend,
1360 		.resume = acpi_subsys_resume,
1361 		.suspend_late = acpi_subsys_suspend_late,
1362 		.suspend_noirq = acpi_subsys_suspend_noirq,
1363 		.resume_noirq = acpi_subsys_resume_noirq,
1364 		.resume_early = acpi_subsys_resume_early,
1365 		.freeze = acpi_subsys_freeze,
1366 		.poweroff = acpi_subsys_poweroff,
1367 		.poweroff_late = acpi_subsys_poweroff_late,
1368 		.poweroff_noirq = acpi_subsys_poweroff_noirq,
1369 		.restore_early = acpi_subsys_restore_early,
1370 #endif
1371 	},
1372 };
1373 
1374 /**
1375  * acpi_dev_pm_detach - Remove ACPI power management from the device.
1376  * @dev: Device to take care of.
1377  * @power_off: Whether or not to try to remove power from the device.
1378  *
1379  * Remove the device from the general ACPI PM domain and remove its wakeup
1380  * notifier.  If @power_off is set, additionally remove power from the device if
1381  * possible.
1382  *
1383  * Callers must ensure proper synchronization of this function with power
1384  * management callbacks.
1385  */
1386 static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1387 {
1388 	struct acpi_device *adev = ACPI_COMPANION(dev);
1389 
1390 	if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1391 		dev_pm_domain_set(dev, NULL);
1392 		acpi_remove_pm_notifier(adev);
1393 		if (power_off) {
1394 			/*
1395 			 * If the device's PM QoS resume latency limit or flags
1396 			 * have been exposed to user space, they have to be
1397 			 * hidden at this point, so that they don't affect the
1398 			 * choice of the low-power state to put the device into.
1399 			 */
1400 			dev_pm_qos_hide_latency_limit(dev);
1401 			dev_pm_qos_hide_flags(dev);
1402 			acpi_device_wakeup_disable(adev);
1403 			acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1404 		}
1405 	}
1406 }
1407 
1408 /**
1409  * acpi_dev_pm_attach - Prepare device for ACPI power management.
1410  * @dev: Device to prepare.
1411  * @power_on: Whether or not to power on the device.
1412  *
1413  * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1414  * attached to it, install a wakeup notification handler for the device and
1415  * add it to the general ACPI PM domain.  If @power_on is set, the device will
1416  * be put into the ACPI D0 state before the function returns.
1417  *
1418  * This assumes that the @dev's bus type uses generic power management callbacks
1419  * (or doesn't use any power management callbacks at all).
1420  *
1421  * Callers must ensure proper synchronization of this function with power
1422  * management callbacks.
1423  */
1424 int acpi_dev_pm_attach(struct device *dev, bool power_on)
1425 {
1426 	/*
1427 	 * Skip devices whose ACPI companions match the device IDs below,
1428 	 * because they require special power management handling incompatible
1429 	 * with the generic ACPI PM domain.
1430 	 */
1431 	static const struct acpi_device_id special_pm_ids[] = {
1432 		ACPI_FAN_DEVICE_IDS,
1433 		{}
1434 	};
1435 	struct acpi_device *adev = ACPI_COMPANION(dev);
1436 
1437 	if (!adev || !acpi_match_device_ids(adev, special_pm_ids))
1438 		return 0;
1439 
1440 	/*
1441 	 * Only attach the power domain to the first device if the
1442 	 * companion is shared by multiple. This is to prevent doing power
1443 	 * management twice.
1444 	 */
1445 	if (!acpi_device_is_first_physical_node(adev, dev))
1446 		return 0;
1447 
1448 	acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1449 	dev_pm_domain_set(dev, &acpi_general_pm_domain);
1450 	if (power_on) {
1451 		acpi_dev_pm_full_power(adev);
1452 		acpi_device_wakeup_disable(adev);
1453 	}
1454 
1455 	dev->pm_domain->detach = acpi_dev_pm_detach;
1456 	return 1;
1457 }
1458 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1459 
1460 /**
1461  * acpi_storage_d3 - Check if D3 should be used in the suspend path
1462  * @dev: Device to check
1463  *
1464  * Return %true if the platform firmware wants @dev to be programmed
1465  * into D3hot or D3cold (if supported) in the suspend path, or %false
1466  * when there is no specific preference. On some platforms, if this
1467  * hint is ignored, @dev may remain unresponsive after suspending the
1468  * platform as a whole.
1469  *
1470  * Although the property has storage in the name it actually is
1471  * applied to the PCIe slot and plugging in a non-storage device the
1472  * same platform restrictions will likely apply.
1473  */
1474 bool acpi_storage_d3(struct device *dev)
1475 {
1476 	struct acpi_device *adev = ACPI_COMPANION(dev);
1477 	u8 val;
1478 
1479 	if (force_storage_d3())
1480 		return true;
1481 
1482 	if (!adev)
1483 		return false;
1484 	if (fwnode_property_read_u8(acpi_fwnode_handle(adev), "StorageD3Enable",
1485 			&val))
1486 		return false;
1487 	return val == 1;
1488 }
1489 EXPORT_SYMBOL_GPL(acpi_storage_d3);
1490 
1491 /**
1492  * acpi_dev_state_d0 - Tell if the device is in D0 power state
1493  * @dev: Physical device the ACPI power state of which to check
1494  *
1495  * On a system without ACPI, return true. On a system with ACPI, return true if
1496  * the current ACPI power state of the device is D0, or false otherwise.
1497  *
1498  * Note that the power state of a device is not well-defined after it has been
1499  * passed to acpi_device_set_power() and before that function returns, so it is
1500  * not valid to ask for the ACPI power state of the device in that time frame.
1501  *
1502  * This function is intended to be used in a driver's probe or remove
1503  * function. See Documentation/firmware-guide/acpi/non-d0-probe.rst for
1504  * more information.
1505  */
1506 bool acpi_dev_state_d0(struct device *dev)
1507 {
1508 	struct acpi_device *adev = ACPI_COMPANION(dev);
1509 
1510 	if (!adev)
1511 		return true;
1512 
1513 	return adev->power.state == ACPI_STATE_D0;
1514 }
1515 EXPORT_SYMBOL_GPL(acpi_dev_state_d0);
1516 
1517 #endif /* CONFIG_PM */
1518