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 */
30const 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
48static 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(handle: device->handle, pathname: "_PSC", NULL, data: &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 */
75int 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(adev: 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, state: &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, state: &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
141static 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(object: adev->handle, pathname: 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 */
162int 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(adev: 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(adev: device, state);
235 if (result)
236 goto end;
237 }
238
239 if (device->power.flags.power_resources)
240 result = acpi_power_transition(device, state: 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, state: &psc);
269 if (result || psc == ACPI_STATE_D0)
270 goto no_change;
271 }
272
273 result = acpi_dev_pm_explicit_set(adev: device, ACPI_STATE_D0);
274 }
275
276end:
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
289no_change:
290 acpi_handle_debug(device->handle, "Already in %s\n",
291 acpi_power_state_string(state));
292 return 0;
293}
294EXPORT_SYMBOL(acpi_device_set_power);
295
296int 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}
305EXPORT_SYMBOL(acpi_bus_set_power);
306
307int 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(adev: device)) {
317 device->flags.initialized = false;
318 return -ENXIO;
319 }
320
321 result = acpi_device_get_power(device, state: &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(adev: 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 */
365int 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(adev: device, ACPI_STATE_D0);
373
374 return ret;
375}
376EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);
377
378static 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 */
393void 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, fn: fix_up_power_if_applicable, NULL);
397}
398EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_extended);
399
400/**
401 * acpi_device_fix_up_power_children - Force a device's children into D0.
402 * @adev: Parent device object whose children's power state is to be fixed up.
403 *
404 * Call acpi_device_fix_up_power() for @adev's children so long as they
405 * are reported as present and enabled.
406 */
407void acpi_device_fix_up_power_children(struct acpi_device *adev)
408{
409 acpi_dev_for_each_child(adev, fn: fix_up_power_if_applicable, NULL);
410}
411EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_children);
412
413int acpi_device_update_power(struct acpi_device *device, int *state_p)
414{
415 int state;
416 int result;
417
418 if (device->power.state == ACPI_STATE_UNKNOWN) {
419 result = acpi_bus_init_power(device);
420 if (!result && state_p)
421 *state_p = device->power.state;
422
423 return result;
424 }
425
426 result = acpi_device_get_power(device, state: &state);
427 if (result)
428 return result;
429
430 if (state == ACPI_STATE_UNKNOWN) {
431 state = ACPI_STATE_D0;
432 result = acpi_device_set_power(device, state);
433 if (result)
434 return result;
435 } else {
436 if (device->power.flags.power_resources) {
437 /*
438 * We don't need to really switch the state, bu we need
439 * to update the power resources' reference counters.
440 */
441 result = acpi_power_transition(device, state);
442 if (result)
443 return result;
444 }
445 device->power.state = state;
446 }
447 if (state_p)
448 *state_p = state;
449
450 return 0;
451}
452EXPORT_SYMBOL_GPL(acpi_device_update_power);
453
454int acpi_bus_update_power(acpi_handle handle, int *state_p)
455{
456 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
457
458 if (device)
459 return acpi_device_update_power(device, state_p);
460
461 return -ENODEV;
462}
463EXPORT_SYMBOL_GPL(acpi_bus_update_power);
464
465bool acpi_bus_power_manageable(acpi_handle handle)
466{
467 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
468
469 return device && device->flags.power_manageable;
470}
471EXPORT_SYMBOL(acpi_bus_power_manageable);
472
473static int acpi_power_up_if_adr_present(struct acpi_device *adev, void *not_used)
474{
475 if (!(adev->flags.power_manageable && adev->pnp.type.bus_address))
476 return 0;
477
478 acpi_handle_debug(adev->handle, "Power state: %s\n",
479 acpi_power_state_string(adev->power.state));
480
481 if (adev->power.state == ACPI_STATE_D3_COLD)
482 return acpi_device_set_power(adev, ACPI_STATE_D0);
483
484 return 0;
485}
486
487/**
488 * acpi_dev_power_up_children_with_adr - Power up childres with valid _ADR
489 * @adev: Parent ACPI device object.
490 *
491 * Change the power states of the direct children of @adev that are in D3cold
492 * and hold valid _ADR objects to D0 in order to allow bus (e.g. PCI)
493 * enumeration code to access them.
494 */
495void acpi_dev_power_up_children_with_adr(struct acpi_device *adev)
496{
497 acpi_dev_for_each_child(adev, fn: acpi_power_up_if_adr_present, NULL);
498}
499
500/**
501 * acpi_dev_power_state_for_wake - Deepest power state for wakeup signaling
502 * @adev: ACPI companion of the target device.
503 *
504 * Evaluate _S0W for @adev and return the value produced by it or return
505 * ACPI_STATE_UNKNOWN on errors (including _S0W not present).
506 */
507u8 acpi_dev_power_state_for_wake(struct acpi_device *adev)
508{
509 unsigned long long state;
510 acpi_status status;
511
512 status = acpi_evaluate_integer(handle: adev->handle, pathname: "_S0W", NULL, data: &state);
513 if (ACPI_FAILURE(status))
514 return ACPI_STATE_UNKNOWN;
515
516 return state;
517}
518
519#ifdef CONFIG_PM
520static DEFINE_MUTEX(acpi_pm_notifier_lock);
521static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
522
523void acpi_pm_wakeup_event(struct device *dev)
524{
525 pm_wakeup_dev_event(dev, msec: 0, hard: acpi_s2idle_wakeup());
526}
527EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
528
529static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
530{
531 struct acpi_device *adev;
532
533 if (val != ACPI_NOTIFY_DEVICE_WAKE)
534 return;
535
536 acpi_handle_debug(handle, "Wake notify\n");
537
538 adev = acpi_get_acpi_dev(handle);
539 if (!adev)
540 return;
541
542 mutex_lock(lock: &acpi_pm_notifier_lock);
543
544 if (adev->wakeup.flags.notifier_present) {
545 pm_wakeup_ws_event(ws: adev->wakeup.ws, msec: 0, hard: acpi_s2idle_wakeup());
546 if (adev->wakeup.context.func) {
547 acpi_handle_debug(handle, "Running %pS for %s\n",
548 adev->wakeup.context.func,
549 dev_name(adev->wakeup.context.dev));
550 adev->wakeup.context.func(&adev->wakeup.context);
551 }
552 }
553
554 mutex_unlock(lock: &acpi_pm_notifier_lock);
555
556 acpi_put_acpi_dev(adev);
557}
558
559/**
560 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
561 * @adev: ACPI device to add the notify handler for.
562 * @dev: Device to generate a wakeup event for while handling the notification.
563 * @func: Work function to execute when handling the notification.
564 *
565 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
566 * PM wakeup events. For example, wakeup events may be generated for bridges
567 * if one of the devices below the bridge is signaling wakeup, even if the
568 * bridge itself doesn't have a wakeup GPE associated with it.
569 */
570acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
571 void (*func)(struct acpi_device_wakeup_context *context))
572{
573 acpi_status status = AE_ALREADY_EXISTS;
574
575 if (!dev && !func)
576 return AE_BAD_PARAMETER;
577
578 mutex_lock(lock: &acpi_pm_notifier_install_lock);
579
580 if (adev->wakeup.flags.notifier_present)
581 goto out;
582
583 status = acpi_install_notify_handler(device: adev->handle, ACPI_SYSTEM_NOTIFY,
584 handler: acpi_pm_notify_handler, NULL);
585 if (ACPI_FAILURE(status))
586 goto out;
587
588 mutex_lock(lock: &acpi_pm_notifier_lock);
589 adev->wakeup.ws = wakeup_source_register(dev: &adev->dev,
590 name: dev_name(dev: &adev->dev));
591 adev->wakeup.context.dev = dev;
592 adev->wakeup.context.func = func;
593 adev->wakeup.flags.notifier_present = true;
594 mutex_unlock(lock: &acpi_pm_notifier_lock);
595
596 out:
597 mutex_unlock(lock: &acpi_pm_notifier_install_lock);
598 return status;
599}
600
601/**
602 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
603 * @adev: ACPI device to remove the notifier from.
604 */
605acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
606{
607 acpi_status status = AE_BAD_PARAMETER;
608
609 mutex_lock(lock: &acpi_pm_notifier_install_lock);
610
611 if (!adev->wakeup.flags.notifier_present)
612 goto out;
613
614 status = acpi_remove_notify_handler(device: adev->handle,
615 ACPI_SYSTEM_NOTIFY,
616 handler: acpi_pm_notify_handler);
617 if (ACPI_FAILURE(status))
618 goto out;
619
620 mutex_lock(lock: &acpi_pm_notifier_lock);
621 adev->wakeup.context.func = NULL;
622 adev->wakeup.context.dev = NULL;
623 wakeup_source_unregister(ws: adev->wakeup.ws);
624 adev->wakeup.flags.notifier_present = false;
625 mutex_unlock(lock: &acpi_pm_notifier_lock);
626
627 out:
628 mutex_unlock(lock: &acpi_pm_notifier_install_lock);
629 return status;
630}
631
632bool acpi_bus_can_wakeup(acpi_handle handle)
633{
634 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
635
636 return device && device->wakeup.flags.valid;
637}
638EXPORT_SYMBOL(acpi_bus_can_wakeup);
639
640bool acpi_pm_device_can_wakeup(struct device *dev)
641{
642 struct acpi_device *adev = ACPI_COMPANION(dev);
643
644 return adev ? acpi_device_can_wakeup(adev) : false;
645}
646
647/**
648 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
649 * @dev: Device whose preferred target power state to return.
650 * @adev: ACPI device node corresponding to @dev.
651 * @target_state: System state to match the resultant device state.
652 * @d_min_p: Location to store the highest power state available to the device.
653 * @d_max_p: Location to store the lowest power state available to the device.
654 *
655 * Find the lowest power (highest number) and highest power (lowest number) ACPI
656 * device power states that the device can be in while the system is in the
657 * state represented by @target_state. Store the integer numbers representing
658 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
659 * respectively.
660 *
661 * Callers must ensure that @dev and @adev are valid pointers and that @adev
662 * actually corresponds to @dev before using this function.
663 *
664 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
665 * returns a value that doesn't make sense. The memory locations pointed to by
666 * @d_max_p and @d_min_p are only modified on success.
667 */
668static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
669 u32 target_state, int *d_min_p, int *d_max_p)
670{
671 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
672 acpi_handle handle = adev->handle;
673 unsigned long long ret;
674 int d_min, d_max;
675 bool wakeup = false;
676 bool has_sxd = false;
677 acpi_status status;
678
679 /*
680 * If the system state is S0, the lowest power state the device can be
681 * in is D3cold, unless the device has _S0W and is supposed to signal
682 * wakeup, in which case the return value of _S0W has to be used as the
683 * lowest power state available to the device.
684 */
685 d_min = ACPI_STATE_D0;
686 d_max = ACPI_STATE_D3_COLD;
687
688 /*
689 * If present, _SxD methods return the minimum D-state (highest power
690 * state) we can use for the corresponding S-states. Otherwise, the
691 * minimum D-state is D0 (ACPI 3.x).
692 */
693 if (target_state > ACPI_STATE_S0) {
694 /*
695 * We rely on acpi_evaluate_integer() not clobbering the integer
696 * provided if AE_NOT_FOUND is returned.
697 */
698 ret = d_min;
699 status = acpi_evaluate_integer(handle, pathname: method, NULL, data: &ret);
700 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
701 || ret > ACPI_STATE_D3_COLD)
702 return -ENODATA;
703
704 /*
705 * We need to handle legacy systems where D3hot and D3cold are
706 * the same and 3 is returned in both cases, so fall back to
707 * D3cold if D3hot is not a valid state.
708 */
709 if (!adev->power.states[ret].flags.valid) {
710 if (ret == ACPI_STATE_D3_HOT)
711 ret = ACPI_STATE_D3_COLD;
712 else
713 return -ENODATA;
714 }
715
716 if (status == AE_OK)
717 has_sxd = true;
718
719 d_min = ret;
720 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
721 && adev->wakeup.sleep_state >= target_state;
722 } else if (device_may_wakeup(dev) && dev->power.wakeirq) {
723 /*
724 * The ACPI subsystem doesn't manage the wake bit for IRQs
725 * defined with ExclusiveAndWake and SharedAndWake. Instead we
726 * expect them to be managed via the PM subsystem. Drivers
727 * should call dev_pm_set_wake_irq to register an IRQ as a wake
728 * source.
729 *
730 * If a device has a wake IRQ attached we need to check the
731 * _S0W method to get the correct wake D-state. Otherwise we
732 * end up putting the device into D3Cold which will more than
733 * likely disable wake functionality.
734 */
735 wakeup = true;
736 } else {
737 /* ACPI GPE is specified in _PRW. */
738 wakeup = adev->wakeup.flags.valid;
739 }
740
741 /*
742 * If _PRW says we can wake up the system from the target sleep state,
743 * the D-state returned by _SxD is sufficient for that (we assume a
744 * wakeup-aware driver if wake is set). Still, if _SxW exists
745 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
746 * can wake the system. _S0W may be valid, too.
747 */
748 if (wakeup) {
749 method[3] = 'W';
750 status = acpi_evaluate_integer(handle, pathname: method, NULL, data: &ret);
751 if (status == AE_NOT_FOUND) {
752 /* No _SxW. In this case, the ACPI spec says that we
753 * must not go into any power state deeper than the
754 * value returned from _SxD.
755 */
756 if (has_sxd && target_state > ACPI_STATE_S0)
757 d_max = d_min;
758 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
759 /* Fall back to D3cold if ret is not a valid state. */
760 if (!adev->power.states[ret].flags.valid)
761 ret = ACPI_STATE_D3_COLD;
762
763 d_max = ret > d_min ? ret : d_min;
764 } else {
765 return -ENODATA;
766 }
767 }
768
769 if (d_min_p)
770 *d_min_p = d_min;
771
772 if (d_max_p)
773 *d_max_p = d_max;
774
775 return 0;
776}
777
778/**
779 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
780 * @dev: Device whose preferred target power state to return.
781 * @d_min_p: Location to store the upper limit of the allowed states range.
782 * @d_max_in: Deepest low-power state to take into consideration.
783 * Return value: Preferred power state of the device on success, -ENODEV
784 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
785 * incorrect, or -ENODATA on ACPI method failure.
786 *
787 * The caller must ensure that @dev is valid before using this function.
788 */
789int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
790{
791 struct acpi_device *adev;
792 int ret, d_min, d_max;
793
794 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
795 return -EINVAL;
796
797 if (d_max_in > ACPI_STATE_D2) {
798 enum pm_qos_flags_status stat;
799
800 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
801 if (stat == PM_QOS_FLAGS_ALL)
802 d_max_in = ACPI_STATE_D2;
803 }
804
805 adev = ACPI_COMPANION(dev);
806 if (!adev) {
807 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
808 return -ENODEV;
809 }
810
811 ret = acpi_dev_pm_get_state(dev, adev, target_state: acpi_target_system_state(),
812 d_min_p: &d_min, d_max_p: &d_max);
813 if (ret)
814 return ret;
815
816 if (d_max_in < d_min)
817 return -EINVAL;
818
819 if (d_max > d_max_in) {
820 for (d_max = d_max_in; d_max > d_min; d_max--) {
821 if (adev->power.states[d_max].flags.valid)
822 break;
823 }
824 }
825
826 if (d_min_p)
827 *d_min_p = d_min;
828
829 return d_max;
830}
831EXPORT_SYMBOL(acpi_pm_device_sleep_state);
832
833/**
834 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
835 * @context: Device wakeup context.
836 */
837static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
838{
839 struct device *dev = context->dev;
840
841 if (dev) {
842 pm_wakeup_event(dev, msec: 0);
843 pm_request_resume(dev);
844 }
845}
846
847static DEFINE_MUTEX(acpi_wakeup_lock);
848
849static int __acpi_device_wakeup_enable(struct acpi_device *adev,
850 u32 target_state)
851{
852 struct acpi_device_wakeup *wakeup = &adev->wakeup;
853 acpi_status status;
854 int error = 0;
855
856 mutex_lock(lock: &acpi_wakeup_lock);
857
858 /*
859 * If the device wakeup power is already enabled, disable it and enable
860 * it again in case it depends on the configuration of subordinate
861 * devices and the conditions have changed since it was enabled last
862 * time.
863 */
864 if (wakeup->enable_count > 0)
865 acpi_disable_wakeup_device_power(dev: adev);
866
867 error = acpi_enable_wakeup_device_power(dev: adev, state: target_state);
868 if (error) {
869 if (wakeup->enable_count > 0) {
870 acpi_disable_gpe(gpe_device: wakeup->gpe_device, gpe_number: wakeup->gpe_number);
871 wakeup->enable_count = 0;
872 }
873 goto out;
874 }
875
876 if (wakeup->enable_count > 0)
877 goto inc;
878
879 status = acpi_enable_gpe(gpe_device: wakeup->gpe_device, gpe_number: wakeup->gpe_number);
880 if (ACPI_FAILURE(status)) {
881 acpi_disable_wakeup_device_power(dev: adev);
882 error = -EIO;
883 goto out;
884 }
885
886 acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",
887 (unsigned int)wakeup->gpe_number);
888
889inc:
890 if (wakeup->enable_count < INT_MAX)
891 wakeup->enable_count++;
892 else
893 acpi_handle_info(adev->handle, "Wakeup enable count out of bounds!\n");
894
895out:
896 mutex_unlock(lock: &acpi_wakeup_lock);
897 return error;
898}
899
900/**
901 * acpi_device_wakeup_enable - Enable wakeup functionality for device.
902 * @adev: ACPI device to enable wakeup functionality for.
903 * @target_state: State the system is transitioning into.
904 *
905 * Enable the GPE associated with @adev so that it can generate wakeup signals
906 * for the device in response to external (remote) events and enable wakeup
907 * power for it.
908 *
909 * Callers must ensure that @adev is a valid ACPI device node before executing
910 * this function.
911 */
912static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
913{
914 return __acpi_device_wakeup_enable(adev, target_state);
915}
916
917/**
918 * acpi_device_wakeup_disable - Disable wakeup functionality for device.
919 * @adev: ACPI device to disable wakeup functionality for.
920 *
921 * Disable the GPE associated with @adev and disable wakeup power for it.
922 *
923 * Callers must ensure that @adev is a valid ACPI device node before executing
924 * this function.
925 */
926static void acpi_device_wakeup_disable(struct acpi_device *adev)
927{
928 struct acpi_device_wakeup *wakeup = &adev->wakeup;
929
930 mutex_lock(lock: &acpi_wakeup_lock);
931
932 if (!wakeup->enable_count)
933 goto out;
934
935 acpi_disable_gpe(gpe_device: wakeup->gpe_device, gpe_number: wakeup->gpe_number);
936 acpi_disable_wakeup_device_power(dev: adev);
937
938 wakeup->enable_count--;
939
940out:
941 mutex_unlock(lock: &acpi_wakeup_lock);
942}
943
944/**
945 * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
946 * @dev: Device to enable/disable to generate wakeup events.
947 * @enable: Whether to enable or disable the wakeup functionality.
948 */
949int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
950{
951 struct acpi_device *adev;
952 int error;
953
954 adev = ACPI_COMPANION(dev);
955 if (!adev) {
956 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
957 return -ENODEV;
958 }
959
960 if (!acpi_device_can_wakeup(adev))
961 return -EINVAL;
962
963 if (!enable) {
964 acpi_device_wakeup_disable(adev);
965 dev_dbg(dev, "Wakeup disabled by ACPI\n");
966 return 0;
967 }
968
969 error = __acpi_device_wakeup_enable(adev, target_state: acpi_target_system_state());
970 if (!error)
971 dev_dbg(dev, "Wakeup enabled by ACPI\n");
972
973 return error;
974}
975EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
976
977/**
978 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
979 * @dev: Device to put into a low-power state.
980 * @adev: ACPI device node corresponding to @dev.
981 * @system_state: System state to choose the device state for.
982 */
983static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
984 u32 system_state)
985{
986 int ret, state;
987
988 if (!acpi_device_power_manageable(adev))
989 return 0;
990
991 ret = acpi_dev_pm_get_state(dev, adev, target_state: system_state, NULL, d_max_p: &state);
992 return ret ? ret : acpi_device_set_power(adev, state);
993}
994
995/**
996 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
997 * @adev: ACPI device node to put into the full-power state.
998 */
999static int acpi_dev_pm_full_power(struct acpi_device *adev)
1000{
1001 return acpi_device_power_manageable(adev) ?
1002 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
1003}
1004
1005/**
1006 * acpi_dev_suspend - Put device into a low-power state using ACPI.
1007 * @dev: Device to put into a low-power state.
1008 * @wakeup: Whether or not to enable wakeup for the device.
1009 *
1010 * Put the given device into a low-power state using the standard ACPI
1011 * mechanism. Set up remote wakeup if desired, choose the state to put the
1012 * device into (this checks if remote wakeup is expected to work too), and set
1013 * the power state of the device.
1014 */
1015int acpi_dev_suspend(struct device *dev, bool wakeup)
1016{
1017 struct acpi_device *adev = ACPI_COMPANION(dev);
1018 u32 target_state = acpi_target_system_state();
1019 int error;
1020
1021 if (!adev)
1022 return 0;
1023
1024 if (wakeup && acpi_device_can_wakeup(adev)) {
1025 error = acpi_device_wakeup_enable(adev, target_state);
1026 if (error)
1027 return -EAGAIN;
1028 } else {
1029 wakeup = false;
1030 }
1031
1032 error = acpi_dev_pm_low_power(dev, adev, system_state: target_state);
1033 if (error && wakeup)
1034 acpi_device_wakeup_disable(adev);
1035
1036 return error;
1037}
1038EXPORT_SYMBOL_GPL(acpi_dev_suspend);
1039
1040/**
1041 * acpi_dev_resume - Put device into the full-power state using ACPI.
1042 * @dev: Device to put into the full-power state.
1043 *
1044 * Put the given device into the full-power state using the standard ACPI
1045 * mechanism. Set the power state of the device to ACPI D0 and disable wakeup.
1046 */
1047int acpi_dev_resume(struct device *dev)
1048{
1049 struct acpi_device *adev = ACPI_COMPANION(dev);
1050 int error;
1051
1052 if (!adev)
1053 return 0;
1054
1055 error = acpi_dev_pm_full_power(adev);
1056 acpi_device_wakeup_disable(adev);
1057 return error;
1058}
1059EXPORT_SYMBOL_GPL(acpi_dev_resume);
1060
1061/**
1062 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
1063 * @dev: Device to suspend.
1064 *
1065 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
1066 * it into a runtime low-power state.
1067 */
1068int acpi_subsys_runtime_suspend(struct device *dev)
1069{
1070 int ret = pm_generic_runtime_suspend(dev);
1071
1072 return ret ? ret : acpi_dev_suspend(dev, true);
1073}
1074EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
1075
1076/**
1077 * acpi_subsys_runtime_resume - Resume device using ACPI.
1078 * @dev: Device to Resume.
1079 *
1080 * Use ACPI to put the given device into the full-power state and carry out the
1081 * generic runtime resume procedure for it.
1082 */
1083int acpi_subsys_runtime_resume(struct device *dev)
1084{
1085 int ret = acpi_dev_resume(dev);
1086
1087 return ret ? ret : pm_generic_runtime_resume(dev);
1088}
1089EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
1090
1091#ifdef CONFIG_PM_SLEEP
1092static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
1093{
1094 u32 sys_target = acpi_target_system_state();
1095 int ret, state;
1096
1097 if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&
1098 device_may_wakeup(dev) != !!adev->wakeup.prepare_count))
1099 return true;
1100
1101 if (sys_target == ACPI_STATE_S0)
1102 return false;
1103
1104 if (adev->power.flags.dsw_present)
1105 return true;
1106
1107 ret = acpi_dev_pm_get_state(dev, adev, target_state: sys_target, NULL, d_max_p: &state);
1108 if (ret)
1109 return true;
1110
1111 return state != adev->power.state;
1112}
1113
1114/**
1115 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
1116 * @dev: Device to prepare.
1117 */
1118int acpi_subsys_prepare(struct device *dev)
1119{
1120 struct acpi_device *adev = ACPI_COMPANION(dev);
1121
1122 dev_pm_set_strict_midlayer(dev, val: true);
1123
1124 if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
1125 int ret = dev->driver->pm->prepare(dev);
1126
1127 if (ret < 0)
1128 return ret;
1129
1130 if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
1131 return 0;
1132 }
1133
1134 return !acpi_dev_needs_resume(dev, adev);
1135}
1136EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
1137
1138/**
1139 * acpi_subsys_complete - Finalize device's resume during system resume.
1140 * @dev: Device to handle.
1141 */
1142void acpi_subsys_complete(struct device *dev)
1143{
1144 pm_generic_complete(dev);
1145 /*
1146 * If the device had been runtime-suspended before the system went into
1147 * the sleep state it is going out of and it has never been resumed till
1148 * now, resume it in case the firmware powered it up.
1149 */
1150 if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
1151 pm_request_resume(dev);
1152
1153 dev_pm_set_strict_midlayer(dev, val: false);
1154}
1155EXPORT_SYMBOL_GPL(acpi_subsys_complete);
1156
1157/**
1158 * acpi_subsys_suspend - Run the device driver's suspend callback.
1159 * @dev: Device to handle.
1160 *
1161 * Follow PCI and resume devices from runtime suspend before running their
1162 * system suspend callbacks, unless the driver can cope with runtime-suspended
1163 * devices during system suspend and there are no ACPI-specific reasons for
1164 * resuming them.
1165 */
1166int acpi_subsys_suspend(struct device *dev)
1167{
1168 if (!dev_pm_smart_suspend(dev) ||
1169 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1170 pm_runtime_resume(dev);
1171
1172 return pm_generic_suspend(dev);
1173}
1174EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
1175
1176/**
1177 * acpi_subsys_suspend_late - Suspend device using ACPI.
1178 * @dev: Device to suspend.
1179 *
1180 * Carry out the generic late suspend procedure for @dev and use ACPI to put
1181 * it into a low-power state during system transition into a sleep state.
1182 */
1183int acpi_subsys_suspend_late(struct device *dev)
1184{
1185 int ret;
1186
1187 if (dev_pm_skip_suspend(dev))
1188 return 0;
1189
1190 ret = pm_generic_suspend_late(dev);
1191 return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
1192}
1193EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
1194
1195/**
1196 * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
1197 * @dev: Device to suspend.
1198 */
1199int acpi_subsys_suspend_noirq(struct device *dev)
1200{
1201 int ret;
1202
1203 if (dev_pm_skip_suspend(dev))
1204 return 0;
1205
1206 ret = pm_generic_suspend_noirq(dev);
1207 if (ret)
1208 return ret;
1209
1210 /*
1211 * If the target system sleep state is suspend-to-idle, it is sufficient
1212 * to check whether or not the device's wakeup settings are good for
1213 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
1214 * acpi_subsys_complete() to take care of fixing up the device's state
1215 * anyway, if need be.
1216 */
1217 if (device_can_wakeup(dev) && !device_may_wakeup(dev))
1218 dev->power.may_skip_resume = false;
1219
1220 return 0;
1221}
1222EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
1223
1224/**
1225 * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
1226 * @dev: Device to handle.
1227 */
1228static int acpi_subsys_resume_noirq(struct device *dev)
1229{
1230 if (dev_pm_skip_resume(dev))
1231 return 0;
1232
1233 return pm_generic_resume_noirq(dev);
1234}
1235
1236/**
1237 * acpi_subsys_resume_early - Resume device using ACPI.
1238 * @dev: Device to Resume.
1239 *
1240 * Use ACPI to put the given device into the full-power state and carry out the
1241 * generic early resume procedure for it during system transition into the
1242 * working state, but only do that if device either defines early resume
1243 * handler, or does not define power operations at all. Otherwise powering up
1244 * of the device is postponed to the normal resume phase.
1245 */
1246static int acpi_subsys_resume_early(struct device *dev)
1247{
1248 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1249 int ret;
1250
1251 if (dev_pm_skip_resume(dev))
1252 return 0;
1253
1254 if (pm && !pm->resume_early) {
1255 dev_dbg(dev, "postponing D0 transition to normal resume stage\n");
1256 return 0;
1257 }
1258
1259 ret = acpi_dev_resume(dev);
1260 return ret ? ret : pm_generic_resume_early(dev);
1261}
1262
1263/**
1264 * acpi_subsys_resume - Resume device using ACPI.
1265 * @dev: Device to Resume.
1266 *
1267 * Use ACPI to put the given device into the full-power state if it has not been
1268 * powered up during early resume phase, and carry out the generic resume
1269 * procedure for it during system transition into the working state.
1270 */
1271static int acpi_subsys_resume(struct device *dev)
1272{
1273 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1274 int ret = 0;
1275
1276 if (!dev_pm_skip_resume(dev) && pm && !pm->resume_early) {
1277 dev_dbg(dev, "executing postponed D0 transition\n");
1278 ret = acpi_dev_resume(dev);
1279 }
1280
1281 return ret ? ret : pm_generic_resume(dev);
1282}
1283
1284/**
1285 * acpi_subsys_freeze - Run the device driver's freeze callback.
1286 * @dev: Device to handle.
1287 */
1288int acpi_subsys_freeze(struct device *dev)
1289{
1290 /*
1291 * Resume all runtime-suspended devices before creating a snapshot
1292 * image of system memory, because the restore kernel generally cannot
1293 * be expected to always handle them consistently and they need to be
1294 * put into the runtime-active metastate during system resume anyway,
1295 * so it is better to ensure that the state saved in the image will be
1296 * always consistent with that.
1297 */
1298 pm_runtime_resume(dev);
1299
1300 return pm_generic_freeze(dev);
1301}
1302EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1303
1304/**
1305 * acpi_subsys_restore_early - Restore device using ACPI.
1306 * @dev: Device to restore.
1307 */
1308int acpi_subsys_restore_early(struct device *dev)
1309{
1310 int ret = acpi_dev_resume(dev);
1311
1312 return ret ? ret : pm_generic_restore_early(dev);
1313}
1314EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);
1315
1316/**
1317 * acpi_subsys_poweroff - Run the device driver's poweroff callback.
1318 * @dev: Device to handle.
1319 *
1320 * Follow PCI and resume devices from runtime suspend before running their
1321 * system poweroff callbacks, unless the driver can cope with runtime-suspended
1322 * devices during system suspend and there are no ACPI-specific reasons for
1323 * resuming them.
1324 */
1325int acpi_subsys_poweroff(struct device *dev)
1326{
1327 if (!dev_pm_smart_suspend(dev) ||
1328 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1329 pm_runtime_resume(dev);
1330
1331 return pm_generic_poweroff(dev);
1332}
1333EXPORT_SYMBOL_GPL(acpi_subsys_poweroff);
1334
1335/**
1336 * acpi_subsys_poweroff_late - Run the device driver's poweroff callback.
1337 * @dev: Device to handle.
1338 *
1339 * Carry out the generic late poweroff procedure for @dev and use ACPI to put
1340 * it into a low-power state during system transition into a sleep state.
1341 */
1342static int acpi_subsys_poweroff_late(struct device *dev)
1343{
1344 int ret;
1345
1346 if (dev_pm_skip_suspend(dev))
1347 return 0;
1348
1349 ret = pm_generic_poweroff_late(dev);
1350 if (ret)
1351 return ret;
1352
1353 return acpi_dev_suspend(dev, device_may_wakeup(dev));
1354}
1355
1356/**
1357 * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.
1358 * @dev: Device to suspend.
1359 */
1360static int acpi_subsys_poweroff_noirq(struct device *dev)
1361{
1362 if (dev_pm_skip_suspend(dev))
1363 return 0;
1364
1365 return pm_generic_poweroff_noirq(dev);
1366}
1367#endif /* CONFIG_PM_SLEEP */
1368
1369static void acpi_dev_pm_detach(struct device *dev, bool power_off);
1370
1371static struct dev_pm_domain acpi_general_pm_domain = {
1372 .ops = {
1373 .runtime_suspend = acpi_subsys_runtime_suspend,
1374 .runtime_resume = acpi_subsys_runtime_resume,
1375#ifdef CONFIG_PM_SLEEP
1376 .prepare = acpi_subsys_prepare,
1377 .complete = acpi_subsys_complete,
1378 .suspend = acpi_subsys_suspend,
1379 .resume = acpi_subsys_resume,
1380 .suspend_late = acpi_subsys_suspend_late,
1381 .suspend_noirq = acpi_subsys_suspend_noirq,
1382 .resume_noirq = acpi_subsys_resume_noirq,
1383 .resume_early = acpi_subsys_resume_early,
1384 .freeze = acpi_subsys_freeze,
1385 .poweroff = acpi_subsys_poweroff,
1386 .poweroff_late = acpi_subsys_poweroff_late,
1387 .poweroff_noirq = acpi_subsys_poweroff_noirq,
1388 .restore_early = acpi_subsys_restore_early,
1389#endif
1390 },
1391 .detach = acpi_dev_pm_detach,
1392};
1393
1394/**
1395 * acpi_dev_pm_detach - Remove ACPI power management from the device.
1396 * @dev: Device to take care of.
1397 * @power_off: Whether or not to try to remove power from the device.
1398 *
1399 * Remove the device from the general ACPI PM domain and remove its wakeup
1400 * notifier. If @power_off is set, additionally remove power from the device if
1401 * possible.
1402 *
1403 * Callers must ensure proper synchronization of this function with power
1404 * management callbacks.
1405 */
1406static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1407{
1408 struct acpi_device *adev = ACPI_COMPANION(dev);
1409
1410 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1411 dev_pm_domain_set(dev, NULL);
1412 acpi_remove_pm_notifier(adev);
1413 if (power_off) {
1414 /*
1415 * If the device's PM QoS resume latency limit or flags
1416 * have been exposed to user space, they have to be
1417 * hidden at this point, so that they don't affect the
1418 * choice of the low-power state to put the device into.
1419 */
1420 dev_pm_qos_hide_latency_limit(dev);
1421 dev_pm_qos_hide_flags(dev);
1422 acpi_device_wakeup_disable(adev);
1423 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1424 }
1425 }
1426}
1427
1428/**
1429 * acpi_dev_pm_attach - Prepare device for ACPI power management.
1430 * @dev: Device to prepare.
1431 * @power_on: Whether or not to power on the device.
1432 *
1433 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1434 * attached to it, install a wakeup notification handler for the device and
1435 * add it to the general ACPI PM domain. If @power_on is set, the device will
1436 * be put into the ACPI D0 state before the function returns.
1437 *
1438 * This assumes that the @dev's bus type uses generic power management callbacks
1439 * (or doesn't use any power management callbacks at all).
1440 *
1441 * Callers must ensure proper synchronization of this function with power
1442 * management callbacks.
1443 */
1444int acpi_dev_pm_attach(struct device *dev, bool power_on)
1445{
1446 /*
1447 * Skip devices whose ACPI companions match the device IDs below,
1448 * because they require special power management handling incompatible
1449 * with the generic ACPI PM domain.
1450 */
1451 static const struct acpi_device_id special_pm_ids[] = {
1452 ACPI_FAN_DEVICE_IDS,
1453 {}
1454 };
1455 struct acpi_device *adev = ACPI_COMPANION(dev);
1456
1457 if (!adev || !acpi_match_device_ids(device: adev, ids: special_pm_ids))
1458 return 0;
1459
1460 /*
1461 * Only attach the power domain to the first device if the
1462 * companion is shared by multiple. This is to prevent doing power
1463 * management twice.
1464 */
1465 if (!acpi_device_is_first_physical_node(adev, dev))
1466 return 0;
1467
1468 acpi_add_pm_notifier(adev, dev, func: acpi_pm_notify_work_func);
1469 dev_pm_domain_set(dev, pd: &acpi_general_pm_domain);
1470 if (power_on) {
1471 acpi_dev_pm_full_power(adev);
1472 acpi_device_wakeup_disable(adev);
1473 }
1474
1475 return 1;
1476}
1477EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1478
1479/**
1480 * acpi_storage_d3 - Check if D3 should be used in the suspend path
1481 * @dev: Device to check
1482 *
1483 * Return %true if the platform firmware wants @dev to be programmed
1484 * into D3hot or D3cold (if supported) in the suspend path, or %false
1485 * when there is no specific preference. On some platforms, if this
1486 * hint is ignored, @dev may remain unresponsive after suspending the
1487 * platform as a whole.
1488 *
1489 * Although the property has storage in the name it actually is
1490 * applied to the PCIe slot and plugging in a non-storage device the
1491 * same platform restrictions will likely apply.
1492 */
1493bool acpi_storage_d3(struct device *dev)
1494{
1495 struct acpi_device *adev = ACPI_COMPANION(dev);
1496 u8 val;
1497
1498 if (force_storage_d3())
1499 return true;
1500
1501 if (!adev)
1502 return false;
1503 if (fwnode_property_read_u8(fwnode: acpi_fwnode_handle(adev), propname: "StorageD3Enable",
1504 val: &val))
1505 return false;
1506 return val == 1;
1507}
1508EXPORT_SYMBOL_GPL(acpi_storage_d3);
1509
1510/**
1511 * acpi_dev_state_d0 - Tell if the device is in D0 power state
1512 * @dev: Physical device the ACPI power state of which to check
1513 *
1514 * On a system without ACPI, return true. On a system with ACPI, return true if
1515 * the current ACPI power state of the device is D0, or false otherwise.
1516 *
1517 * Note that the power state of a device is not well-defined after it has been
1518 * passed to acpi_device_set_power() and before that function returns, so it is
1519 * not valid to ask for the ACPI power state of the device in that time frame.
1520 *
1521 * This function is intended to be used in a driver's probe or remove
1522 * function. See Documentation/firmware-guide/acpi/non-d0-probe.rst for
1523 * more information.
1524 */
1525bool acpi_dev_state_d0(struct device *dev)
1526{
1527 struct acpi_device *adev = ACPI_COMPANION(dev);
1528
1529 if (!adev)
1530 return true;
1531
1532 return adev->power.state == ACPI_STATE_D0;
1533}
1534EXPORT_SYMBOL_GPL(acpi_dev_state_d0);
1535
1536#endif /* CONFIG_PM */
1537