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