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1/*
2 * drivers/acpi/device_pm.c - ACPI device power management routines.
3 *
4 * Copyright (C) 2012, Intel Corp.
5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as published
11 * by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
19 */
20
21#include <linux/acpi.h>
22#include <linux/export.h>
23#include <linux/mutex.h>
24#include <linux/pm_qos.h>
25#include <linux/pm_domain.h>
26#include <linux/pm_runtime.h>
27
28#include "internal.h"
29
30#define _COMPONENT ACPI_POWER_COMPONENT
31ACPI_MODULE_NAME("device_pm");
32
33/**
34 * acpi_power_state_string - String representation of ACPI device power state.
35 * @state: ACPI device power state to return the string representation of.
36 */
37const char *acpi_power_state_string(int state)
38{
39 switch (state) {
40 case ACPI_STATE_D0:
41 return "D0";
42 case ACPI_STATE_D1:
43 return "D1";
44 case ACPI_STATE_D2:
45 return "D2";
46 case ACPI_STATE_D3_HOT:
47 return "D3hot";
48 case ACPI_STATE_D3_COLD:
49 return "D3cold";
50 default:
51 return "(unknown)";
52 }
53}
54
55/**
56 * acpi_device_get_power - Get power state of an ACPI device.
57 * @device: Device to get the power state of.
58 * @state: Place to store the power state of the device.
59 *
60 * This function does not update the device's power.state field, but it may
61 * update its parent's power.state field (when the parent's power state is
62 * unknown and the device's power state turns out to be D0).
63 */
64int acpi_device_get_power(struct acpi_device *device, int *state)
65{
66 int result = ACPI_STATE_UNKNOWN;
67
68 if (!device || !state)
69 return -EINVAL;
70
71 if (!device->flags.power_manageable) {
72 /* TBD: Non-recursive algorithm for walking up hierarchy. */
73 *state = device->parent ?
74 device->parent->power.state : ACPI_STATE_D0;
75 goto out;
76 }
77
78 /*
79 * Get the device's power state from power resources settings and _PSC,
80 * if available.
81 */
82 if (device->power.flags.power_resources) {
83 int error = acpi_power_get_inferred_state(device, &result);
84 if (error)
85 return error;
86 }
87 if (device->power.flags.explicit_get) {
88 acpi_handle handle = device->handle;
89 unsigned long long psc;
90 acpi_status status;
91
92 status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
93 if (ACPI_FAILURE(status))
94 return -ENODEV;
95
96 /*
97 * The power resources settings may indicate a power state
98 * shallower than the actual power state of the device, because
99 * the same power resources may be referenced by other devices.
100 *
101 * For systems predating ACPI 4.0 we assume that D3hot is the
102 * deepest state that can be supported.
103 */
104 if (psc > result && psc < ACPI_STATE_D3_COLD)
105 result = psc;
106 else if (result == ACPI_STATE_UNKNOWN)
107 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
108 }
109
110 /*
111 * If we were unsure about the device parent's power state up to this
112 * point, the fact that the device is in D0 implies that the parent has
113 * to be in D0 too, except if ignore_parent is set.
114 */
115 if (!device->power.flags.ignore_parent && device->parent
116 && device->parent->power.state == ACPI_STATE_UNKNOWN
117 && result == ACPI_STATE_D0)
118 device->parent->power.state = ACPI_STATE_D0;
119
120 *state = result;
121
122 out:
123 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
124 device->pnp.bus_id, acpi_power_state_string(*state)));
125
126 return 0;
127}
128
129static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
130{
131 if (adev->power.states[state].flags.explicit_set) {
132 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
133 acpi_status status;
134
135 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
136 if (ACPI_FAILURE(status))
137 return -ENODEV;
138 }
139 return 0;
140}
141
142/**
143 * acpi_device_set_power - Set power state of an ACPI device.
144 * @device: Device to set the power state of.
145 * @state: New power state to set.
146 *
147 * Callers must ensure that the device is power manageable before using this
148 * function.
149 */
150int acpi_device_set_power(struct acpi_device *device, int state)
151{
152 int target_state = state;
153 int result = 0;
154
155 if (!device || !device->flags.power_manageable
156 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
157 return -EINVAL;
158
159 /* Make sure this is a valid target state */
160
161 if (state == device->power.state) {
162 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
163 device->pnp.bus_id,
164 acpi_power_state_string(state)));
165 return 0;
166 }
167
168 if (state == ACPI_STATE_D3_COLD) {
169 /*
170 * For transitions to D3cold we need to execute _PS3 and then
171 * possibly drop references to the power resources in use.
172 */
173 state = ACPI_STATE_D3_HOT;
174 /* If _PR3 is not available, use D3hot as the target state. */
175 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
176 target_state = state;
177 } else if (!device->power.states[state].flags.valid) {
178 dev_warn(&device->dev, "Power state %s not supported\n",
179 acpi_power_state_string(state));
180 return -ENODEV;
181 }
182
183 if (!device->power.flags.ignore_parent &&
184 device->parent && (state < device->parent->power.state)) {
185 dev_warn(&device->dev,
186 "Cannot transition to power state %s for parent in %s\n",
187 acpi_power_state_string(state),
188 acpi_power_state_string(device->parent->power.state));
189 return -ENODEV;
190 }
191
192 /*
193 * Transition Power
194 * ----------------
195 * In accordance with ACPI 6, _PSx is executed before manipulating power
196 * resources, unless the target state is D0, in which case _PS0 is
197 * supposed to be executed after turning the power resources on.
198 */
199 if (state > ACPI_STATE_D0) {
200 /*
201 * According to ACPI 6, devices cannot go from lower-power
202 * (deeper) states to higher-power (shallower) states.
203 */
204 if (state < device->power.state) {
205 dev_warn(&device->dev, "Cannot transition from %s to %s\n",
206 acpi_power_state_string(device->power.state),
207 acpi_power_state_string(state));
208 return -ENODEV;
209 }
210
211 result = acpi_dev_pm_explicit_set(device, state);
212 if (result)
213 goto end;
214
215 if (device->power.flags.power_resources)
216 result = acpi_power_transition(device, target_state);
217 } else {
218 if (device->power.flags.power_resources) {
219 result = acpi_power_transition(device, ACPI_STATE_D0);
220 if (result)
221 goto end;
222 }
223 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
224 }
225
226 end:
227 if (result) {
228 dev_warn(&device->dev, "Failed to change power state to %s\n",
229 acpi_power_state_string(state));
230 } else {
231 device->power.state = target_state;
232 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
233 "Device [%s] transitioned to %s\n",
234 device->pnp.bus_id,
235 acpi_power_state_string(state)));
236 }
237
238 return result;
239}
240EXPORT_SYMBOL(acpi_device_set_power);
241
242int acpi_bus_set_power(acpi_handle handle, int state)
243{
244 struct acpi_device *device;
245 int result;
246
247 result = acpi_bus_get_device(handle, &device);
248 if (result)
249 return result;
250
251 return acpi_device_set_power(device, state);
252}
253EXPORT_SYMBOL(acpi_bus_set_power);
254
255int acpi_bus_init_power(struct acpi_device *device)
256{
257 int state;
258 int result;
259
260 if (!device)
261 return -EINVAL;
262
263 device->power.state = ACPI_STATE_UNKNOWN;
264 if (!acpi_device_is_present(device))
265 return -ENXIO;
266
267 result = acpi_device_get_power(device, &state);
268 if (result)
269 return result;
270
271 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
272 /* Reference count the power resources. */
273 result = acpi_power_on_resources(device, state);
274 if (result)
275 return result;
276
277 if (state == ACPI_STATE_D0) {
278 /*
279 * If _PSC is not present and the state inferred from
280 * power resources appears to be D0, it still may be
281 * necessary to execute _PS0 at this point, because
282 * another device using the same power resources may
283 * have been put into D0 previously and that's why we
284 * see D0 here.
285 */
286 result = acpi_dev_pm_explicit_set(device, state);
287 if (result)
288 return result;
289 }
290 } else if (state == ACPI_STATE_UNKNOWN) {
291 /*
292 * No power resources and missing _PSC? Cross fingers and make
293 * it D0 in hope that this is what the BIOS put the device into.
294 * [We tried to force D0 here by executing _PS0, but that broke
295 * Toshiba P870-303 in a nasty way.]
296 */
297 state = ACPI_STATE_D0;
298 }
299 device->power.state = state;
300 return 0;
301}
302
303/**
304 * acpi_device_fix_up_power - Force device with missing _PSC into D0.
305 * @device: Device object whose power state is to be fixed up.
306 *
307 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
308 * are assumed to be put into D0 by the BIOS. However, in some cases that may
309 * not be the case and this function should be used then.
310 */
311int acpi_device_fix_up_power(struct acpi_device *device)
312{
313 int ret = 0;
314
315 if (!device->power.flags.power_resources
316 && !device->power.flags.explicit_get
317 && device->power.state == ACPI_STATE_D0)
318 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
319
320 return ret;
321}
322
323int acpi_device_update_power(struct acpi_device *device, int *state_p)
324{
325 int state;
326 int result;
327
328 if (device->power.state == ACPI_STATE_UNKNOWN) {
329 result = acpi_bus_init_power(device);
330 if (!result && state_p)
331 *state_p = device->power.state;
332
333 return result;
334 }
335
336 result = acpi_device_get_power(device, &state);
337 if (result)
338 return result;
339
340 if (state == ACPI_STATE_UNKNOWN) {
341 state = ACPI_STATE_D0;
342 result = acpi_device_set_power(device, state);
343 if (result)
344 return result;
345 } else {
346 if (device->power.flags.power_resources) {
347 /*
348 * We don't need to really switch the state, bu we need
349 * to update the power resources' reference counters.
350 */
351 result = acpi_power_transition(device, state);
352 if (result)
353 return result;
354 }
355 device->power.state = state;
356 }
357 if (state_p)
358 *state_p = state;
359
360 return 0;
361}
362EXPORT_SYMBOL_GPL(acpi_device_update_power);
363
364int acpi_bus_update_power(acpi_handle handle, int *state_p)
365{
366 struct acpi_device *device;
367 int result;
368
369 result = acpi_bus_get_device(handle, &device);
370 return result ? result : acpi_device_update_power(device, state_p);
371}
372EXPORT_SYMBOL_GPL(acpi_bus_update_power);
373
374bool acpi_bus_power_manageable(acpi_handle handle)
375{
376 struct acpi_device *device;
377 int result;
378
379 result = acpi_bus_get_device(handle, &device);
380 return result ? false : device->flags.power_manageable;
381}
382EXPORT_SYMBOL(acpi_bus_power_manageable);
383
384#ifdef CONFIG_PM
385static DEFINE_MUTEX(acpi_pm_notifier_lock);
386
387static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
388{
389 struct acpi_device *adev;
390
391 if (val != ACPI_NOTIFY_DEVICE_WAKE)
392 return;
393
394 adev = acpi_bus_get_acpi_device(handle);
395 if (!adev)
396 return;
397
398 mutex_lock(&acpi_pm_notifier_lock);
399
400 if (adev->wakeup.flags.notifier_present) {
401 __pm_wakeup_event(adev->wakeup.ws, 0);
402 if (adev->wakeup.context.work.func)
403 queue_pm_work(&adev->wakeup.context.work);
404 }
405
406 mutex_unlock(&acpi_pm_notifier_lock);
407
408 acpi_bus_put_acpi_device(adev);
409}
410
411/**
412 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
413 * @adev: ACPI device to add the notify handler for.
414 * @dev: Device to generate a wakeup event for while handling the notification.
415 * @work_func: Work function to execute when handling the notification.
416 *
417 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
418 * PM wakeup events. For example, wakeup events may be generated for bridges
419 * if one of the devices below the bridge is signaling wakeup, even if the
420 * bridge itself doesn't have a wakeup GPE associated with it.
421 */
422acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
423 void (*work_func)(struct work_struct *work))
424{
425 acpi_status status = AE_ALREADY_EXISTS;
426
427 if (!dev && !work_func)
428 return AE_BAD_PARAMETER;
429
430 mutex_lock(&acpi_pm_notifier_lock);
431
432 if (adev->wakeup.flags.notifier_present)
433 goto out;
434
435 adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
436 adev->wakeup.context.dev = dev;
437 if (work_func)
438 INIT_WORK(&adev->wakeup.context.work, work_func);
439
440 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
441 acpi_pm_notify_handler, NULL);
442 if (ACPI_FAILURE(status))
443 goto out;
444
445 adev->wakeup.flags.notifier_present = true;
446
447 out:
448 mutex_unlock(&acpi_pm_notifier_lock);
449 return status;
450}
451
452/**
453 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
454 * @adev: ACPI device to remove the notifier from.
455 */
456acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
457{
458 acpi_status status = AE_BAD_PARAMETER;
459
460 mutex_lock(&acpi_pm_notifier_lock);
461
462 if (!adev->wakeup.flags.notifier_present)
463 goto out;
464
465 status = acpi_remove_notify_handler(adev->handle,
466 ACPI_SYSTEM_NOTIFY,
467 acpi_pm_notify_handler);
468 if (ACPI_FAILURE(status))
469 goto out;
470
471 if (adev->wakeup.context.work.func) {
472 cancel_work_sync(&adev->wakeup.context.work);
473 adev->wakeup.context.work.func = NULL;
474 }
475 adev->wakeup.context.dev = NULL;
476 wakeup_source_unregister(adev->wakeup.ws);
477
478 adev->wakeup.flags.notifier_present = false;
479
480 out:
481 mutex_unlock(&acpi_pm_notifier_lock);
482 return status;
483}
484
485bool acpi_bus_can_wakeup(acpi_handle handle)
486{
487 struct acpi_device *device;
488 int result;
489
490 result = acpi_bus_get_device(handle, &device);
491 return result ? false : device->wakeup.flags.valid;
492}
493EXPORT_SYMBOL(acpi_bus_can_wakeup);
494
495/**
496 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
497 * @dev: Device whose preferred target power state to return.
498 * @adev: ACPI device node corresponding to @dev.
499 * @target_state: System state to match the resultant device state.
500 * @d_min_p: Location to store the highest power state available to the device.
501 * @d_max_p: Location to store the lowest power state available to the device.
502 *
503 * Find the lowest power (highest number) and highest power (lowest number) ACPI
504 * device power states that the device can be in while the system is in the
505 * state represented by @target_state. Store the integer numbers representing
506 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
507 * respectively.
508 *
509 * Callers must ensure that @dev and @adev are valid pointers and that @adev
510 * actually corresponds to @dev before using this function.
511 *
512 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
513 * returns a value that doesn't make sense. The memory locations pointed to by
514 * @d_max_p and @d_min_p are only modified on success.
515 */
516static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
517 u32 target_state, int *d_min_p, int *d_max_p)
518{
519 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
520 acpi_handle handle = adev->handle;
521 unsigned long long ret;
522 int d_min, d_max;
523 bool wakeup = false;
524 acpi_status status;
525
526 /*
527 * If the system state is S0, the lowest power state the device can be
528 * in is D3cold, unless the device has _S0W and is supposed to signal
529 * wakeup, in which case the return value of _S0W has to be used as the
530 * lowest power state available to the device.
531 */
532 d_min = ACPI_STATE_D0;
533 d_max = ACPI_STATE_D3_COLD;
534
535 /*
536 * If present, _SxD methods return the minimum D-state (highest power
537 * state) we can use for the corresponding S-states. Otherwise, the
538 * minimum D-state is D0 (ACPI 3.x).
539 */
540 if (target_state > ACPI_STATE_S0) {
541 /*
542 * We rely on acpi_evaluate_integer() not clobbering the integer
543 * provided if AE_NOT_FOUND is returned.
544 */
545 ret = d_min;
546 status = acpi_evaluate_integer(handle, method, NULL, &ret);
547 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
548 || ret > ACPI_STATE_D3_COLD)
549 return -ENODATA;
550
551 /*
552 * We need to handle legacy systems where D3hot and D3cold are
553 * the same and 3 is returned in both cases, so fall back to
554 * D3cold if D3hot is not a valid state.
555 */
556 if (!adev->power.states[ret].flags.valid) {
557 if (ret == ACPI_STATE_D3_HOT)
558 ret = ACPI_STATE_D3_COLD;
559 else
560 return -ENODATA;
561 }
562 d_min = ret;
563 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
564 && adev->wakeup.sleep_state >= target_state;
565 } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
566 PM_QOS_FLAGS_NONE) {
567 wakeup = adev->wakeup.flags.valid;
568 }
569
570 /*
571 * If _PRW says we can wake up the system from the target sleep state,
572 * the D-state returned by _SxD is sufficient for that (we assume a
573 * wakeup-aware driver if wake is set). Still, if _SxW exists
574 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
575 * can wake the system. _S0W may be valid, too.
576 */
577 if (wakeup) {
578 method[3] = 'W';
579 status = acpi_evaluate_integer(handle, method, NULL, &ret);
580 if (status == AE_NOT_FOUND) {
581 if (target_state > ACPI_STATE_S0)
582 d_max = d_min;
583 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
584 /* Fall back to D3cold if ret is not a valid state. */
585 if (!adev->power.states[ret].flags.valid)
586 ret = ACPI_STATE_D3_COLD;
587
588 d_max = ret > d_min ? ret : d_min;
589 } else {
590 return -ENODATA;
591 }
592 }
593
594 if (d_min_p)
595 *d_min_p = d_min;
596
597 if (d_max_p)
598 *d_max_p = d_max;
599
600 return 0;
601}
602
603/**
604 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
605 * @dev: Device whose preferred target power state to return.
606 * @d_min_p: Location to store the upper limit of the allowed states range.
607 * @d_max_in: Deepest low-power state to take into consideration.
608 * Return value: Preferred power state of the device on success, -ENODEV
609 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
610 * incorrect, or -ENODATA on ACPI method failure.
611 *
612 * The caller must ensure that @dev is valid before using this function.
613 */
614int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
615{
616 struct acpi_device *adev;
617 int ret, d_min, d_max;
618
619 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
620 return -EINVAL;
621
622 if (d_max_in > ACPI_STATE_D2) {
623 enum pm_qos_flags_status stat;
624
625 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
626 if (stat == PM_QOS_FLAGS_ALL)
627 d_max_in = ACPI_STATE_D2;
628 }
629
630 adev = ACPI_COMPANION(dev);
631 if (!adev) {
632 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
633 return -ENODEV;
634 }
635
636 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
637 &d_min, &d_max);
638 if (ret)
639 return ret;
640
641 if (d_max_in < d_min)
642 return -EINVAL;
643
644 if (d_max > d_max_in) {
645 for (d_max = d_max_in; d_max > d_min; d_max--) {
646 if (adev->power.states[d_max].flags.valid)
647 break;
648 }
649 }
650
651 if (d_min_p)
652 *d_min_p = d_min;
653
654 return d_max;
655}
656EXPORT_SYMBOL(acpi_pm_device_sleep_state);
657
658/**
659 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
660 * @work: Work item to handle.
661 */
662static void acpi_pm_notify_work_func(struct work_struct *work)
663{
664 struct device *dev;
665
666 dev = container_of(work, struct acpi_device_wakeup_context, work)->dev;
667 if (dev) {
668 pm_wakeup_event(dev, 0);
669 pm_runtime_resume(dev);
670 }
671}
672
673/**
674 * acpi_device_wakeup - Enable/disable wakeup functionality for device.
675 * @adev: ACPI device to enable/disable wakeup functionality for.
676 * @target_state: State the system is transitioning into.
677 * @enable: Whether to enable or disable the wakeup functionality.
678 *
679 * Enable/disable the GPE associated with @adev so that it can generate
680 * wakeup signals for the device in response to external (remote) events and
681 * enable/disable device wakeup power.
682 *
683 * Callers must ensure that @adev is a valid ACPI device node before executing
684 * this function.
685 */
686static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state,
687 bool enable)
688{
689 struct acpi_device_wakeup *wakeup = &adev->wakeup;
690
691 if (enable) {
692 acpi_status res;
693 int error;
694
695 error = acpi_enable_wakeup_device_power(adev, target_state);
696 if (error)
697 return error;
698
699 if (adev->wakeup.flags.enabled)
700 return 0;
701
702 res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
703 if (ACPI_SUCCESS(res)) {
704 adev->wakeup.flags.enabled = 1;
705 } else {
706 acpi_disable_wakeup_device_power(adev);
707 return -EIO;
708 }
709 } else {
710 if (adev->wakeup.flags.enabled) {
711 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
712 adev->wakeup.flags.enabled = 0;
713 }
714 acpi_disable_wakeup_device_power(adev);
715 }
716 return 0;
717}
718
719/**
720 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
721 * @dev: Device to enable/disable the platform to wake up.
722 * @enable: Whether to enable or disable the wakeup functionality.
723 */
724int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
725{
726 struct acpi_device *adev;
727
728 if (!device_run_wake(phys_dev))
729 return -EINVAL;
730
731 adev = ACPI_COMPANION(phys_dev);
732 if (!adev) {
733 dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__);
734 return -ENODEV;
735 }
736
737 return acpi_device_wakeup(adev, ACPI_STATE_S0, enable);
738}
739EXPORT_SYMBOL(acpi_pm_device_run_wake);
740
741#ifdef CONFIG_PM_SLEEP
742/**
743 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
744 * @dev: Device to enable/desible to wake up the system from sleep states.
745 * @enable: Whether to enable or disable @dev to wake up the system.
746 */
747int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
748{
749 struct acpi_device *adev;
750 int error;
751
752 if (!device_can_wakeup(dev))
753 return -EINVAL;
754
755 adev = ACPI_COMPANION(dev);
756 if (!adev) {
757 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
758 return -ENODEV;
759 }
760
761 error = acpi_device_wakeup(adev, acpi_target_system_state(), enable);
762 if (!error)
763 dev_info(dev, "System wakeup %s by ACPI\n",
764 enable ? "enabled" : "disabled");
765
766 return error;
767}
768#endif /* CONFIG_PM_SLEEP */
769
770/**
771 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
772 * @dev: Device to put into a low-power state.
773 * @adev: ACPI device node corresponding to @dev.
774 * @system_state: System state to choose the device state for.
775 */
776static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
777 u32 system_state)
778{
779 int ret, state;
780
781 if (!acpi_device_power_manageable(adev))
782 return 0;
783
784 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
785 return ret ? ret : acpi_device_set_power(adev, state);
786}
787
788/**
789 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
790 * @adev: ACPI device node to put into the full-power state.
791 */
792static int acpi_dev_pm_full_power(struct acpi_device *adev)
793{
794 return acpi_device_power_manageable(adev) ?
795 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
796}
797
798/**
799 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
800 * @dev: Device to put into a low-power state.
801 *
802 * Put the given device into a runtime low-power state using the standard ACPI
803 * mechanism. Set up remote wakeup if desired, choose the state to put the
804 * device into (this checks if remote wakeup is expected to work too), and set
805 * the power state of the device.
806 */
807int acpi_dev_runtime_suspend(struct device *dev)
808{
809 struct acpi_device *adev = ACPI_COMPANION(dev);
810 bool remote_wakeup;
811 int error;
812
813 if (!adev)
814 return 0;
815
816 remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
817 PM_QOS_FLAGS_NONE;
818 error = acpi_device_wakeup(adev, ACPI_STATE_S0, remote_wakeup);
819 if (remote_wakeup && error)
820 return -EAGAIN;
821
822 error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
823 if (error)
824 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
825
826 return error;
827}
828EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
829
830/**
831 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
832 * @dev: Device to put into the full-power state.
833 *
834 * Put the given device into the full-power state using the standard ACPI
835 * mechanism at run time. Set the power state of the device to ACPI D0 and
836 * disable remote wakeup.
837 */
838int acpi_dev_runtime_resume(struct device *dev)
839{
840 struct acpi_device *adev = ACPI_COMPANION(dev);
841 int error;
842
843 if (!adev)
844 return 0;
845
846 error = acpi_dev_pm_full_power(adev);
847 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
848 return error;
849}
850EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);
851
852/**
853 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
854 * @dev: Device to suspend.
855 *
856 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
857 * it into a runtime low-power state.
858 */
859int acpi_subsys_runtime_suspend(struct device *dev)
860{
861 int ret = pm_generic_runtime_suspend(dev);
862 return ret ? ret : acpi_dev_runtime_suspend(dev);
863}
864EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
865
866/**
867 * acpi_subsys_runtime_resume - Resume device using ACPI.
868 * @dev: Device to Resume.
869 *
870 * Use ACPI to put the given device into the full-power state and carry out the
871 * generic runtime resume procedure for it.
872 */
873int acpi_subsys_runtime_resume(struct device *dev)
874{
875 int ret = acpi_dev_runtime_resume(dev);
876 return ret ? ret : pm_generic_runtime_resume(dev);
877}
878EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
879
880#ifdef CONFIG_PM_SLEEP
881/**
882 * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
883 * @dev: Device to put into a low-power state.
884 *
885 * Put the given device into a low-power state during system transition to a
886 * sleep state using the standard ACPI mechanism. Set up system wakeup if
887 * desired, choose the state to put the device into (this checks if system
888 * wakeup is expected to work too), and set the power state of the device.
889 */
890int acpi_dev_suspend_late(struct device *dev)
891{
892 struct acpi_device *adev = ACPI_COMPANION(dev);
893 u32 target_state;
894 bool wakeup;
895 int error;
896
897 if (!adev)
898 return 0;
899
900 target_state = acpi_target_system_state();
901 wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev);
902 error = acpi_device_wakeup(adev, target_state, wakeup);
903 if (wakeup && error)
904 return error;
905
906 error = acpi_dev_pm_low_power(dev, adev, target_state);
907 if (error)
908 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
909
910 return error;
911}
912EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
913
914/**
915 * acpi_dev_resume_early - Put device into the full-power state using ACPI.
916 * @dev: Device to put into the full-power state.
917 *
918 * Put the given device into the full-power state using the standard ACPI
919 * mechanism during system transition to the working state. Set the power
920 * state of the device to ACPI D0 and disable remote wakeup.
921 */
922int acpi_dev_resume_early(struct device *dev)
923{
924 struct acpi_device *adev = ACPI_COMPANION(dev);
925 int error;
926
927 if (!adev)
928 return 0;
929
930 error = acpi_dev_pm_full_power(adev);
931 acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
932 return error;
933}
934EXPORT_SYMBOL_GPL(acpi_dev_resume_early);
935
936/**
937 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
938 * @dev: Device to prepare.
939 */
940int acpi_subsys_prepare(struct device *dev)
941{
942 struct acpi_device *adev = ACPI_COMPANION(dev);
943 u32 sys_target;
944 int ret, state;
945
946 ret = pm_generic_prepare(dev);
947 if (ret < 0)
948 return ret;
949
950 if (!adev || !pm_runtime_suspended(dev)
951 || device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
952 return 0;
953
954 sys_target = acpi_target_system_state();
955 if (sys_target == ACPI_STATE_S0)
956 return 1;
957
958 if (adev->power.flags.dsw_present)
959 return 0;
960
961 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
962 return !ret && state == adev->power.state;
963}
964EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
965
966/**
967 * acpi_subsys_suspend - Run the device driver's suspend callback.
968 * @dev: Device to handle.
969 *
970 * Follow PCI and resume devices suspended at run time before running their
971 * system suspend callbacks.
972 */
973int acpi_subsys_suspend(struct device *dev)
974{
975 pm_runtime_resume(dev);
976 return pm_generic_suspend(dev);
977}
978EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
979
980/**
981 * acpi_subsys_suspend_late - Suspend device using ACPI.
982 * @dev: Device to suspend.
983 *
984 * Carry out the generic late suspend procedure for @dev and use ACPI to put
985 * it into a low-power state during system transition into a sleep state.
986 */
987int acpi_subsys_suspend_late(struct device *dev)
988{
989 int ret = pm_generic_suspend_late(dev);
990 return ret ? ret : acpi_dev_suspend_late(dev);
991}
992EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
993
994/**
995 * acpi_subsys_resume_early - Resume device using ACPI.
996 * @dev: Device to Resume.
997 *
998 * Use ACPI to put the given device into the full-power state and carry out the
999 * generic early resume procedure for it during system transition into the
1000 * working state.
1001 */
1002int acpi_subsys_resume_early(struct device *dev)
1003{
1004 int ret = acpi_dev_resume_early(dev);
1005 return ret ? ret : pm_generic_resume_early(dev);
1006}
1007EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
1008
1009/**
1010 * acpi_subsys_freeze - Run the device driver's freeze callback.
1011 * @dev: Device to handle.
1012 */
1013int acpi_subsys_freeze(struct device *dev)
1014{
1015 /*
1016 * This used to be done in acpi_subsys_prepare() for all devices and
1017 * some drivers may depend on it, so do it here. Ideally, however,
1018 * runtime-suspended devices should not be touched during freeze/thaw
1019 * transitions.
1020 */
1021 pm_runtime_resume(dev);
1022 return pm_generic_freeze(dev);
1023}
1024EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1025
1026#endif /* CONFIG_PM_SLEEP */
1027
1028static struct dev_pm_domain acpi_general_pm_domain = {
1029 .ops = {
1030 .runtime_suspend = acpi_subsys_runtime_suspend,
1031 .runtime_resume = acpi_subsys_runtime_resume,
1032#ifdef CONFIG_PM_SLEEP
1033 .prepare = acpi_subsys_prepare,
1034 .complete = pm_complete_with_resume_check,
1035 .suspend = acpi_subsys_suspend,
1036 .suspend_late = acpi_subsys_suspend_late,
1037 .resume_early = acpi_subsys_resume_early,
1038 .freeze = acpi_subsys_freeze,
1039 .poweroff = acpi_subsys_suspend,
1040 .poweroff_late = acpi_subsys_suspend_late,
1041 .restore_early = acpi_subsys_resume_early,
1042#endif
1043 },
1044};
1045
1046/**
1047 * acpi_dev_pm_detach - Remove ACPI power management from the device.
1048 * @dev: Device to take care of.
1049 * @power_off: Whether or not to try to remove power from the device.
1050 *
1051 * Remove the device from the general ACPI PM domain and remove its wakeup
1052 * notifier. If @power_off is set, additionally remove power from the device if
1053 * possible.
1054 *
1055 * Callers must ensure proper synchronization of this function with power
1056 * management callbacks.
1057 */
1058static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1059{
1060 struct acpi_device *adev = ACPI_COMPANION(dev);
1061
1062 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1063 dev_pm_domain_set(dev, NULL);
1064 acpi_remove_pm_notifier(adev);
1065 if (power_off) {
1066 /*
1067 * If the device's PM QoS resume latency limit or flags
1068 * have been exposed to user space, they have to be
1069 * hidden at this point, so that they don't affect the
1070 * choice of the low-power state to put the device into.
1071 */
1072 dev_pm_qos_hide_latency_limit(dev);
1073 dev_pm_qos_hide_flags(dev);
1074 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
1075 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1076 }
1077 }
1078}
1079
1080/**
1081 * acpi_dev_pm_attach - Prepare device for ACPI power management.
1082 * @dev: Device to prepare.
1083 * @power_on: Whether or not to power on the device.
1084 *
1085 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1086 * attached to it, install a wakeup notification handler for the device and
1087 * add it to the general ACPI PM domain. If @power_on is set, the device will
1088 * be put into the ACPI D0 state before the function returns.
1089 *
1090 * This assumes that the @dev's bus type uses generic power management callbacks
1091 * (or doesn't use any power management callbacks at all).
1092 *
1093 * Callers must ensure proper synchronization of this function with power
1094 * management callbacks.
1095 */
1096int acpi_dev_pm_attach(struct device *dev, bool power_on)
1097{
1098 struct acpi_device *adev = ACPI_COMPANION(dev);
1099
1100 if (!adev)
1101 return -ENODEV;
1102
1103 if (dev->pm_domain)
1104 return -EEXIST;
1105
1106 /*
1107 * Only attach the power domain to the first device if the
1108 * companion is shared by multiple. This is to prevent doing power
1109 * management twice.
1110 */
1111 if (!acpi_device_is_first_physical_node(adev, dev))
1112 return -EBUSY;
1113
1114 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1115 dev_pm_domain_set(dev, &acpi_general_pm_domain);
1116 if (power_on) {
1117 acpi_dev_pm_full_power(adev);
1118 acpi_device_wakeup(adev, ACPI_STATE_S0, false);
1119 }
1120
1121 dev->pm_domain->detach = acpi_dev_pm_detach;
1122 return 0;
1123}
1124EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1125#endif /* CONFIG_PM */
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(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 struct acpi_device *parent;
79 int error;
80
81 if (!device || !state)
82 return -EINVAL;
83
84 parent = acpi_dev_parent(device);
85
86 if (!device->flags.power_manageable) {
87 /* TBD: Non-recursive algorithm for walking up hierarchy. */
88 *state = parent ? parent->power.state : ACPI_STATE_D0;
89 goto out;
90 }
91
92 /*
93 * Get the device's power state from power resources settings and _PSC,
94 * if available.
95 */
96 if (device->power.flags.power_resources) {
97 error = acpi_power_get_inferred_state(device, &result);
98 if (error)
99 return error;
100 }
101 if (device->power.flags.explicit_get) {
102 int psc;
103
104 error = acpi_dev_pm_explicit_get(device, &psc);
105 if (error)
106 return error;
107
108 /*
109 * The power resources settings may indicate a power state
110 * shallower than the actual power state of the device, because
111 * the same power resources may be referenced by other devices.
112 *
113 * For systems predating ACPI 4.0 we assume that D3hot is the
114 * deepest state that can be supported.
115 */
116 if (psc > result && psc < ACPI_STATE_D3_COLD)
117 result = psc;
118 else if (result == ACPI_STATE_UNKNOWN)
119 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
120 }
121
122 /*
123 * If we were unsure about the device parent's power state up to this
124 * point, the fact that the device is in D0 implies that the parent has
125 * to be in D0 too, except if ignore_parent is set.
126 */
127 if (!device->power.flags.ignore_parent && parent &&
128 parent->power.state == ACPI_STATE_UNKNOWN &&
129 result == ACPI_STATE_D0)
130 parent->power.state = ACPI_STATE_D0;
131
132 *state = result;
133
134 out:
135 acpi_handle_debug(device->handle, "Power state: %s\n",
136 acpi_power_state_string(*state));
137
138 return 0;
139}
140
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(adev->handle, method, NULL, NULL);
148 if (ACPI_FAILURE(status))
149 return -ENODEV;
150 }
151 return 0;
152}
153
154/**
155 * acpi_device_set_power - Set power state of an ACPI device.
156 * @device: Device to set the power state of.
157 * @state: New power state to set.
158 *
159 * Callers must ensure that the device is power manageable before using this
160 * function.
161 */
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(device);
200 if (parent && state < parent->power.state) {
201 acpi_handle_debug(device->handle,
202 "Cannot transition to %s for parent in %s\n",
203 acpi_power_state_string(state),
204 acpi_power_state_string(parent->power.state));
205 return -ENODEV;
206 }
207 }
208
209 /*
210 * Transition Power
211 * ----------------
212 * In accordance with ACPI 6, _PSx is executed before manipulating power
213 * resources, unless the target state is D0, in which case _PS0 is
214 * supposed to be executed after turning the power resources on.
215 */
216 if (state > ACPI_STATE_D0) {
217 /*
218 * According to ACPI 6, devices cannot go from lower-power
219 * (deeper) states to higher-power (shallower) states.
220 */
221 if (state < device->power.state) {
222 acpi_handle_debug(device->handle,
223 "Cannot transition from %s to %s\n",
224 acpi_power_state_string(device->power.state),
225 acpi_power_state_string(state));
226 return -ENODEV;
227 }
228
229 /*
230 * If the device goes from D3hot to D3cold, _PS3 has been
231 * evaluated for it already, so skip it in that case.
232 */
233 if (device->power.state < ACPI_STATE_D3_HOT) {
234 result = acpi_dev_pm_explicit_set(device, state);
235 if (result)
236 goto end;
237 }
238
239 if (device->power.flags.power_resources)
240 result = acpi_power_transition(device, target_state);
241 } else {
242 int cur_state = device->power.state;
243
244 if (device->power.flags.power_resources) {
245 result = acpi_power_transition(device, ACPI_STATE_D0);
246 if (result)
247 goto end;
248 }
249
250 if (cur_state == ACPI_STATE_D0) {
251 int psc;
252
253 /* Nothing to do here if _PSC is not present. */
254 if (!device->power.flags.explicit_get)
255 goto no_change;
256
257 /*
258 * The power state of the device was set to D0 last
259 * time, but that might have happened before a
260 * system-wide transition involving the platform
261 * firmware, so it may be necessary to evaluate _PS0
262 * for the device here. However, use extra care here
263 * and evaluate _PSC to check the device's current power
264 * state, and only invoke _PS0 if the evaluation of _PSC
265 * is successful and it returns a power state different
266 * from D0.
267 */
268 result = acpi_dev_pm_explicit_get(device, &psc);
269 if (result || psc == ACPI_STATE_D0)
270 goto no_change;
271 }
272
273 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
274 }
275
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(device)) {
317 device->flags.initialized = false;
318 return -ENXIO;
319 }
320
321 result = acpi_device_get_power(device, &state);
322 if (result)
323 return result;
324
325 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
326 /* Reference count the power resources. */
327 result = acpi_power_on_resources(device, state);
328 if (result)
329 return result;
330
331 if (state == ACPI_STATE_D0) {
332 /*
333 * If _PSC is not present and the state inferred from
334 * power resources appears to be D0, it still may be
335 * necessary to execute _PS0 at this point, because
336 * another device using the same power resources may
337 * have been put into D0 previously and that's why we
338 * see D0 here.
339 */
340 result = acpi_dev_pm_explicit_set(device, state);
341 if (result)
342 return result;
343 }
344 } else if (state == ACPI_STATE_UNKNOWN) {
345 /*
346 * No power resources and missing _PSC? Cross fingers and make
347 * it D0 in hope that this is what the BIOS put the device into.
348 * [We tried to force D0 here by executing _PS0, but that broke
349 * Toshiba P870-303 in a nasty way.]
350 */
351 state = ACPI_STATE_D0;
352 }
353 device->power.state = state;
354 return 0;
355}
356
357/**
358 * acpi_device_fix_up_power - Force device with missing _PSC into D0.
359 * @device: Device object whose power state is to be fixed up.
360 *
361 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
362 * are assumed to be put into D0 by the BIOS. However, in some cases that may
363 * not be the case and this function should be used then.
364 */
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(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, fix_up_power_if_applicable, NULL);
397}
398EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_extended);
399
400int acpi_device_update_power(struct acpi_device *device, int *state_p)
401{
402 int state;
403 int result;
404
405 if (device->power.state == ACPI_STATE_UNKNOWN) {
406 result = acpi_bus_init_power(device);
407 if (!result && state_p)
408 *state_p = device->power.state;
409
410 return result;
411 }
412
413 result = acpi_device_get_power(device, &state);
414 if (result)
415 return result;
416
417 if (state == ACPI_STATE_UNKNOWN) {
418 state = ACPI_STATE_D0;
419 result = acpi_device_set_power(device, state);
420 if (result)
421 return result;
422 } else {
423 if (device->power.flags.power_resources) {
424 /*
425 * We don't need to really switch the state, bu we need
426 * to update the power resources' reference counters.
427 */
428 result = acpi_power_transition(device, state);
429 if (result)
430 return result;
431 }
432 device->power.state = state;
433 }
434 if (state_p)
435 *state_p = state;
436
437 return 0;
438}
439EXPORT_SYMBOL_GPL(acpi_device_update_power);
440
441int acpi_bus_update_power(acpi_handle handle, int *state_p)
442{
443 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
444
445 if (device)
446 return acpi_device_update_power(device, state_p);
447
448 return -ENODEV;
449}
450EXPORT_SYMBOL_GPL(acpi_bus_update_power);
451
452bool acpi_bus_power_manageable(acpi_handle handle)
453{
454 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
455
456 return device && device->flags.power_manageable;
457}
458EXPORT_SYMBOL(acpi_bus_power_manageable);
459
460static int acpi_power_up_if_adr_present(struct acpi_device *adev, void *not_used)
461{
462 if (!(adev->flags.power_manageable && adev->pnp.type.bus_address))
463 return 0;
464
465 acpi_handle_debug(adev->handle, "Power state: %s\n",
466 acpi_power_state_string(adev->power.state));
467
468 if (adev->power.state == ACPI_STATE_D3_COLD)
469 return acpi_device_set_power(adev, ACPI_STATE_D0);
470
471 return 0;
472}
473
474/**
475 * acpi_dev_power_up_children_with_adr - Power up childres with valid _ADR
476 * @adev: Parent ACPI device object.
477 *
478 * Change the power states of the direct children of @adev that are in D3cold
479 * and hold valid _ADR objects to D0 in order to allow bus (e.g. PCI)
480 * enumeration code to access them.
481 */
482void acpi_dev_power_up_children_with_adr(struct acpi_device *adev)
483{
484 acpi_dev_for_each_child(adev, acpi_power_up_if_adr_present, NULL);
485}
486
487#ifdef CONFIG_PM
488static DEFINE_MUTEX(acpi_pm_notifier_lock);
489static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
490
491void acpi_pm_wakeup_event(struct device *dev)
492{
493 pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
494}
495EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
496
497static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
498{
499 struct acpi_device *adev;
500
501 if (val != ACPI_NOTIFY_DEVICE_WAKE)
502 return;
503
504 acpi_handle_debug(handle, "Wake notify\n");
505
506 adev = acpi_get_acpi_dev(handle);
507 if (!adev)
508 return;
509
510 mutex_lock(&acpi_pm_notifier_lock);
511
512 if (adev->wakeup.flags.notifier_present) {
513 pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
514 if (adev->wakeup.context.func) {
515 acpi_handle_debug(handle, "Running %pS for %s\n",
516 adev->wakeup.context.func,
517 dev_name(adev->wakeup.context.dev));
518 adev->wakeup.context.func(&adev->wakeup.context);
519 }
520 }
521
522 mutex_unlock(&acpi_pm_notifier_lock);
523
524 acpi_put_acpi_dev(adev);
525}
526
527/**
528 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
529 * @adev: ACPI device to add the notify handler for.
530 * @dev: Device to generate a wakeup event for while handling the notification.
531 * @func: Work function to execute when handling the notification.
532 *
533 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
534 * PM wakeup events. For example, wakeup events may be generated for bridges
535 * if one of the devices below the bridge is signaling wakeup, even if the
536 * bridge itself doesn't have a wakeup GPE associated with it.
537 */
538acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
539 void (*func)(struct acpi_device_wakeup_context *context))
540{
541 acpi_status status = AE_ALREADY_EXISTS;
542
543 if (!dev && !func)
544 return AE_BAD_PARAMETER;
545
546 mutex_lock(&acpi_pm_notifier_install_lock);
547
548 if (adev->wakeup.flags.notifier_present)
549 goto out;
550
551 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
552 acpi_pm_notify_handler, NULL);
553 if (ACPI_FAILURE(status))
554 goto out;
555
556 mutex_lock(&acpi_pm_notifier_lock);
557 adev->wakeup.ws = wakeup_source_register(&adev->dev,
558 dev_name(&adev->dev));
559 adev->wakeup.context.dev = dev;
560 adev->wakeup.context.func = func;
561 adev->wakeup.flags.notifier_present = true;
562 mutex_unlock(&acpi_pm_notifier_lock);
563
564 out:
565 mutex_unlock(&acpi_pm_notifier_install_lock);
566 return status;
567}
568
569/**
570 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
571 * @adev: ACPI device to remove the notifier from.
572 */
573acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
574{
575 acpi_status status = AE_BAD_PARAMETER;
576
577 mutex_lock(&acpi_pm_notifier_install_lock);
578
579 if (!adev->wakeup.flags.notifier_present)
580 goto out;
581
582 status = acpi_remove_notify_handler(adev->handle,
583 ACPI_SYSTEM_NOTIFY,
584 acpi_pm_notify_handler);
585 if (ACPI_FAILURE(status))
586 goto out;
587
588 mutex_lock(&acpi_pm_notifier_lock);
589 adev->wakeup.context.func = NULL;
590 adev->wakeup.context.dev = NULL;
591 wakeup_source_unregister(adev->wakeup.ws);
592 adev->wakeup.flags.notifier_present = false;
593 mutex_unlock(&acpi_pm_notifier_lock);
594
595 out:
596 mutex_unlock(&acpi_pm_notifier_install_lock);
597 return status;
598}
599
600bool acpi_bus_can_wakeup(acpi_handle handle)
601{
602 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
603
604 return device && device->wakeup.flags.valid;
605}
606EXPORT_SYMBOL(acpi_bus_can_wakeup);
607
608bool acpi_pm_device_can_wakeup(struct device *dev)
609{
610 struct acpi_device *adev = ACPI_COMPANION(dev);
611
612 return adev ? acpi_device_can_wakeup(adev) : false;
613}
614
615/**
616 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
617 * @dev: Device whose preferred target power state to return.
618 * @adev: ACPI device node corresponding to @dev.
619 * @target_state: System state to match the resultant device state.
620 * @d_min_p: Location to store the highest power state available to the device.
621 * @d_max_p: Location to store the lowest power state available to the device.
622 *
623 * Find the lowest power (highest number) and highest power (lowest number) ACPI
624 * device power states that the device can be in while the system is in the
625 * state represented by @target_state. Store the integer numbers representing
626 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
627 * respectively.
628 *
629 * Callers must ensure that @dev and @adev are valid pointers and that @adev
630 * actually corresponds to @dev before using this function.
631 *
632 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
633 * returns a value that doesn't make sense. The memory locations pointed to by
634 * @d_max_p and @d_min_p are only modified on success.
635 */
636static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
637 u32 target_state, int *d_min_p, int *d_max_p)
638{
639 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
640 acpi_handle handle = adev->handle;
641 unsigned long long ret;
642 int d_min, d_max;
643 bool wakeup = false;
644 bool has_sxd = false;
645 acpi_status status;
646
647 /*
648 * If the system state is S0, the lowest power state the device can be
649 * in is D3cold, unless the device has _S0W and is supposed to signal
650 * wakeup, in which case the return value of _S0W has to be used as the
651 * lowest power state available to the device.
652 */
653 d_min = ACPI_STATE_D0;
654 d_max = ACPI_STATE_D3_COLD;
655
656 /*
657 * If present, _SxD methods return the minimum D-state (highest power
658 * state) we can use for the corresponding S-states. Otherwise, the
659 * minimum D-state is D0 (ACPI 3.x).
660 */
661 if (target_state > ACPI_STATE_S0) {
662 /*
663 * We rely on acpi_evaluate_integer() not clobbering the integer
664 * provided if AE_NOT_FOUND is returned.
665 */
666 ret = d_min;
667 status = acpi_evaluate_integer(handle, method, NULL, &ret);
668 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
669 || ret > ACPI_STATE_D3_COLD)
670 return -ENODATA;
671
672 /*
673 * We need to handle legacy systems where D3hot and D3cold are
674 * the same and 3 is returned in both cases, so fall back to
675 * D3cold if D3hot is not a valid state.
676 */
677 if (!adev->power.states[ret].flags.valid) {
678 if (ret == ACPI_STATE_D3_HOT)
679 ret = ACPI_STATE_D3_COLD;
680 else
681 return -ENODATA;
682 }
683
684 if (status == AE_OK)
685 has_sxd = true;
686
687 d_min = ret;
688 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
689 && adev->wakeup.sleep_state >= target_state;
690 } else if (device_may_wakeup(dev) && dev->power.wakeirq) {
691 /*
692 * The ACPI subsystem doesn't manage the wake bit for IRQs
693 * defined with ExclusiveAndWake and SharedAndWake. Instead we
694 * expect them to be managed via the PM subsystem. Drivers
695 * should call dev_pm_set_wake_irq to register an IRQ as a wake
696 * source.
697 *
698 * If a device has a wake IRQ attached we need to check the
699 * _S0W method to get the correct wake D-state. Otherwise we
700 * end up putting the device into D3Cold which will more than
701 * likely disable wake functionality.
702 */
703 wakeup = true;
704 } else {
705 /* ACPI GPE is specified in _PRW. */
706 wakeup = adev->wakeup.flags.valid;
707 }
708
709 /*
710 * If _PRW says we can wake up the system from the target sleep state,
711 * the D-state returned by _SxD is sufficient for that (we assume a
712 * wakeup-aware driver if wake is set). Still, if _SxW exists
713 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
714 * can wake the system. _S0W may be valid, too.
715 */
716 if (wakeup) {
717 method[3] = 'W';
718 status = acpi_evaluate_integer(handle, method, NULL, &ret);
719 if (status == AE_NOT_FOUND) {
720 /* No _SxW. In this case, the ACPI spec says that we
721 * must not go into any power state deeper than the
722 * value returned from _SxD.
723 */
724 if (has_sxd && target_state > ACPI_STATE_S0)
725 d_max = d_min;
726 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
727 /* Fall back to D3cold if ret is not a valid state. */
728 if (!adev->power.states[ret].flags.valid)
729 ret = ACPI_STATE_D3_COLD;
730
731 d_max = ret > d_min ? ret : d_min;
732 } else {
733 return -ENODATA;
734 }
735 }
736
737 if (d_min_p)
738 *d_min_p = d_min;
739
740 if (d_max_p)
741 *d_max_p = d_max;
742
743 return 0;
744}
745
746/**
747 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
748 * @dev: Device whose preferred target power state to return.
749 * @d_min_p: Location to store the upper limit of the allowed states range.
750 * @d_max_in: Deepest low-power state to take into consideration.
751 * Return value: Preferred power state of the device on success, -ENODEV
752 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
753 * incorrect, or -ENODATA on ACPI method failure.
754 *
755 * The caller must ensure that @dev is valid before using this function.
756 */
757int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
758{
759 struct acpi_device *adev;
760 int ret, d_min, d_max;
761
762 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
763 return -EINVAL;
764
765 if (d_max_in > ACPI_STATE_D2) {
766 enum pm_qos_flags_status stat;
767
768 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
769 if (stat == PM_QOS_FLAGS_ALL)
770 d_max_in = ACPI_STATE_D2;
771 }
772
773 adev = ACPI_COMPANION(dev);
774 if (!adev) {
775 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
776 return -ENODEV;
777 }
778
779 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
780 &d_min, &d_max);
781 if (ret)
782 return ret;
783
784 if (d_max_in < d_min)
785 return -EINVAL;
786
787 if (d_max > d_max_in) {
788 for (d_max = d_max_in; d_max > d_min; d_max--) {
789 if (adev->power.states[d_max].flags.valid)
790 break;
791 }
792 }
793
794 if (d_min_p)
795 *d_min_p = d_min;
796
797 return d_max;
798}
799EXPORT_SYMBOL(acpi_pm_device_sleep_state);
800
801/**
802 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
803 * @context: Device wakeup context.
804 */
805static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
806{
807 struct device *dev = context->dev;
808
809 if (dev) {
810 pm_wakeup_event(dev, 0);
811 pm_request_resume(dev);
812 }
813}
814
815static DEFINE_MUTEX(acpi_wakeup_lock);
816
817static int __acpi_device_wakeup_enable(struct acpi_device *adev,
818 u32 target_state)
819{
820 struct acpi_device_wakeup *wakeup = &adev->wakeup;
821 acpi_status status;
822 int error = 0;
823
824 mutex_lock(&acpi_wakeup_lock);
825
826 /*
827 * If the device wakeup power is already enabled, disable it and enable
828 * it again in case it depends on the configuration of subordinate
829 * devices and the conditions have changed since it was enabled last
830 * time.
831 */
832 if (wakeup->enable_count > 0)
833 acpi_disable_wakeup_device_power(adev);
834
835 error = acpi_enable_wakeup_device_power(adev, target_state);
836 if (error) {
837 if (wakeup->enable_count > 0) {
838 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
839 wakeup->enable_count = 0;
840 }
841 goto out;
842 }
843
844 if (wakeup->enable_count > 0)
845 goto inc;
846
847 status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
848 if (ACPI_FAILURE(status)) {
849 acpi_disable_wakeup_device_power(adev);
850 error = -EIO;
851 goto out;
852 }
853
854 acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",
855 (unsigned int)wakeup->gpe_number);
856
857inc:
858 if (wakeup->enable_count < INT_MAX)
859 wakeup->enable_count++;
860 else
861 acpi_handle_info(adev->handle, "Wakeup enable count out of bounds!\n");
862
863out:
864 mutex_unlock(&acpi_wakeup_lock);
865 return error;
866}
867
868/**
869 * acpi_device_wakeup_enable - Enable wakeup functionality for device.
870 * @adev: ACPI device to enable wakeup functionality for.
871 * @target_state: State the system is transitioning into.
872 *
873 * Enable the GPE associated with @adev so that it can generate wakeup signals
874 * for the device in response to external (remote) events and enable wakeup
875 * power for it.
876 *
877 * Callers must ensure that @adev is a valid ACPI device node before executing
878 * this function.
879 */
880static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
881{
882 return __acpi_device_wakeup_enable(adev, target_state);
883}
884
885/**
886 * acpi_device_wakeup_disable - Disable wakeup functionality for device.
887 * @adev: ACPI device to disable wakeup functionality for.
888 *
889 * Disable the GPE associated with @adev and disable wakeup power for it.
890 *
891 * Callers must ensure that @adev is a valid ACPI device node before executing
892 * this function.
893 */
894static void acpi_device_wakeup_disable(struct acpi_device *adev)
895{
896 struct acpi_device_wakeup *wakeup = &adev->wakeup;
897
898 mutex_lock(&acpi_wakeup_lock);
899
900 if (!wakeup->enable_count)
901 goto out;
902
903 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
904 acpi_disable_wakeup_device_power(adev);
905
906 wakeup->enable_count--;
907
908out:
909 mutex_unlock(&acpi_wakeup_lock);
910}
911
912/**
913 * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
914 * @dev: Device to enable/disable to generate wakeup events.
915 * @enable: Whether to enable or disable the wakeup functionality.
916 */
917int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
918{
919 struct acpi_device *adev;
920 int error;
921
922 adev = ACPI_COMPANION(dev);
923 if (!adev) {
924 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
925 return -ENODEV;
926 }
927
928 if (!acpi_device_can_wakeup(adev))
929 return -EINVAL;
930
931 if (!enable) {
932 acpi_device_wakeup_disable(adev);
933 dev_dbg(dev, "Wakeup disabled by ACPI\n");
934 return 0;
935 }
936
937 error = __acpi_device_wakeup_enable(adev, acpi_target_system_state());
938 if (!error)
939 dev_dbg(dev, "Wakeup enabled by ACPI\n");
940
941 return error;
942}
943EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
944
945/**
946 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
947 * @dev: Device to put into a low-power state.
948 * @adev: ACPI device node corresponding to @dev.
949 * @system_state: System state to choose the device state for.
950 */
951static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
952 u32 system_state)
953{
954 int ret, state;
955
956 if (!acpi_device_power_manageable(adev))
957 return 0;
958
959 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
960 return ret ? ret : acpi_device_set_power(adev, state);
961}
962
963/**
964 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
965 * @adev: ACPI device node to put into the full-power state.
966 */
967static int acpi_dev_pm_full_power(struct acpi_device *adev)
968{
969 return acpi_device_power_manageable(adev) ?
970 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
971}
972
973/**
974 * acpi_dev_suspend - Put device into a low-power state using ACPI.
975 * @dev: Device to put into a low-power state.
976 * @wakeup: Whether or not to enable wakeup for the device.
977 *
978 * Put the given device into a low-power state using the standard ACPI
979 * mechanism. Set up remote wakeup if desired, choose the state to put the
980 * device into (this checks if remote wakeup is expected to work too), and set
981 * the power state of the device.
982 */
983int acpi_dev_suspend(struct device *dev, bool wakeup)
984{
985 struct acpi_device *adev = ACPI_COMPANION(dev);
986 u32 target_state = acpi_target_system_state();
987 int error;
988
989 if (!adev)
990 return 0;
991
992 if (wakeup && acpi_device_can_wakeup(adev)) {
993 error = acpi_device_wakeup_enable(adev, target_state);
994 if (error)
995 return -EAGAIN;
996 } else {
997 wakeup = false;
998 }
999
1000 error = acpi_dev_pm_low_power(dev, adev, target_state);
1001 if (error && wakeup)
1002 acpi_device_wakeup_disable(adev);
1003
1004 return error;
1005}
1006EXPORT_SYMBOL_GPL(acpi_dev_suspend);
1007
1008/**
1009 * acpi_dev_resume - Put device into the full-power state using ACPI.
1010 * @dev: Device to put into the full-power state.
1011 *
1012 * Put the given device into the full-power state using the standard ACPI
1013 * mechanism. Set the power state of the device to ACPI D0 and disable wakeup.
1014 */
1015int acpi_dev_resume(struct device *dev)
1016{
1017 struct acpi_device *adev = ACPI_COMPANION(dev);
1018 int error;
1019
1020 if (!adev)
1021 return 0;
1022
1023 error = acpi_dev_pm_full_power(adev);
1024 acpi_device_wakeup_disable(adev);
1025 return error;
1026}
1027EXPORT_SYMBOL_GPL(acpi_dev_resume);
1028
1029/**
1030 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
1031 * @dev: Device to suspend.
1032 *
1033 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
1034 * it into a runtime low-power state.
1035 */
1036int acpi_subsys_runtime_suspend(struct device *dev)
1037{
1038 int ret = pm_generic_runtime_suspend(dev);
1039
1040 return ret ? ret : acpi_dev_suspend(dev, true);
1041}
1042EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
1043
1044/**
1045 * acpi_subsys_runtime_resume - Resume device using ACPI.
1046 * @dev: Device to Resume.
1047 *
1048 * Use ACPI to put the given device into the full-power state and carry out the
1049 * generic runtime resume procedure for it.
1050 */
1051int acpi_subsys_runtime_resume(struct device *dev)
1052{
1053 int ret = acpi_dev_resume(dev);
1054
1055 return ret ? ret : pm_generic_runtime_resume(dev);
1056}
1057EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
1058
1059#ifdef CONFIG_PM_SLEEP
1060static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
1061{
1062 u32 sys_target = acpi_target_system_state();
1063 int ret, state;
1064
1065 if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&
1066 device_may_wakeup(dev) != !!adev->wakeup.prepare_count))
1067 return true;
1068
1069 if (sys_target == ACPI_STATE_S0)
1070 return false;
1071
1072 if (adev->power.flags.dsw_present)
1073 return true;
1074
1075 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
1076 if (ret)
1077 return true;
1078
1079 return state != adev->power.state;
1080}
1081
1082/**
1083 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
1084 * @dev: Device to prepare.
1085 */
1086int acpi_subsys_prepare(struct device *dev)
1087{
1088 struct acpi_device *adev = ACPI_COMPANION(dev);
1089
1090 if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
1091 int ret = dev->driver->pm->prepare(dev);
1092
1093 if (ret < 0)
1094 return ret;
1095
1096 if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
1097 return 0;
1098 }
1099
1100 return !acpi_dev_needs_resume(dev, adev);
1101}
1102EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
1103
1104/**
1105 * acpi_subsys_complete - Finalize device's resume during system resume.
1106 * @dev: Device to handle.
1107 */
1108void acpi_subsys_complete(struct device *dev)
1109{
1110 pm_generic_complete(dev);
1111 /*
1112 * If the device had been runtime-suspended before the system went into
1113 * the sleep state it is going out of and it has never been resumed till
1114 * now, resume it in case the firmware powered it up.
1115 */
1116 if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
1117 pm_request_resume(dev);
1118}
1119EXPORT_SYMBOL_GPL(acpi_subsys_complete);
1120
1121/**
1122 * acpi_subsys_suspend - Run the device driver's suspend callback.
1123 * @dev: Device to handle.
1124 *
1125 * Follow PCI and resume devices from runtime suspend before running their
1126 * system suspend callbacks, unless the driver can cope with runtime-suspended
1127 * devices during system suspend and there are no ACPI-specific reasons for
1128 * resuming them.
1129 */
1130int acpi_subsys_suspend(struct device *dev)
1131{
1132 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1133 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1134 pm_runtime_resume(dev);
1135
1136 return pm_generic_suspend(dev);
1137}
1138EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
1139
1140/**
1141 * acpi_subsys_suspend_late - Suspend device using ACPI.
1142 * @dev: Device to suspend.
1143 *
1144 * Carry out the generic late suspend procedure for @dev and use ACPI to put
1145 * it into a low-power state during system transition into a sleep state.
1146 */
1147int acpi_subsys_suspend_late(struct device *dev)
1148{
1149 int ret;
1150
1151 if (dev_pm_skip_suspend(dev))
1152 return 0;
1153
1154 ret = pm_generic_suspend_late(dev);
1155 return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
1156}
1157EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
1158
1159/**
1160 * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
1161 * @dev: Device to suspend.
1162 */
1163int acpi_subsys_suspend_noirq(struct device *dev)
1164{
1165 int ret;
1166
1167 if (dev_pm_skip_suspend(dev))
1168 return 0;
1169
1170 ret = pm_generic_suspend_noirq(dev);
1171 if (ret)
1172 return ret;
1173
1174 /*
1175 * If the target system sleep state is suspend-to-idle, it is sufficient
1176 * to check whether or not the device's wakeup settings are good for
1177 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
1178 * acpi_subsys_complete() to take care of fixing up the device's state
1179 * anyway, if need be.
1180 */
1181 if (device_can_wakeup(dev) && !device_may_wakeup(dev))
1182 dev->power.may_skip_resume = false;
1183
1184 return 0;
1185}
1186EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
1187
1188/**
1189 * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
1190 * @dev: Device to handle.
1191 */
1192static int acpi_subsys_resume_noirq(struct device *dev)
1193{
1194 if (dev_pm_skip_resume(dev))
1195 return 0;
1196
1197 return pm_generic_resume_noirq(dev);
1198}
1199
1200/**
1201 * acpi_subsys_resume_early - Resume device using ACPI.
1202 * @dev: Device to Resume.
1203 *
1204 * Use ACPI to put the given device into the full-power state and carry out the
1205 * generic early resume procedure for it during system transition into the
1206 * working state, but only do that if device either defines early resume
1207 * handler, or does not define power operations at all. Otherwise powering up
1208 * of the device is postponed to the normal resume phase.
1209 */
1210static int acpi_subsys_resume_early(struct device *dev)
1211{
1212 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1213 int ret;
1214
1215 if (dev_pm_skip_resume(dev))
1216 return 0;
1217
1218 if (pm && !pm->resume_early) {
1219 dev_dbg(dev, "postponing D0 transition to normal resume stage\n");
1220 return 0;
1221 }
1222
1223 ret = acpi_dev_resume(dev);
1224 return ret ? ret : pm_generic_resume_early(dev);
1225}
1226
1227/**
1228 * acpi_subsys_resume - Resume device using ACPI.
1229 * @dev: Device to Resume.
1230 *
1231 * Use ACPI to put the given device into the full-power state if it has not been
1232 * powered up during early resume phase, and carry out the generic resume
1233 * procedure for it during system transition into the working state.
1234 */
1235static int acpi_subsys_resume(struct device *dev)
1236{
1237 const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
1238 int ret = 0;
1239
1240 if (!dev_pm_skip_resume(dev) && pm && !pm->resume_early) {
1241 dev_dbg(dev, "executing postponed D0 transition\n");
1242 ret = acpi_dev_resume(dev);
1243 }
1244
1245 return ret ? ret : pm_generic_resume(dev);
1246}
1247
1248/**
1249 * acpi_subsys_freeze - Run the device driver's freeze callback.
1250 * @dev: Device to handle.
1251 */
1252int acpi_subsys_freeze(struct device *dev)
1253{
1254 /*
1255 * Resume all runtime-suspended devices before creating a snapshot
1256 * image of system memory, because the restore kernel generally cannot
1257 * be expected to always handle them consistently and they need to be
1258 * put into the runtime-active metastate during system resume anyway,
1259 * so it is better to ensure that the state saved in the image will be
1260 * always consistent with that.
1261 */
1262 pm_runtime_resume(dev);
1263
1264 return pm_generic_freeze(dev);
1265}
1266EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1267
1268/**
1269 * acpi_subsys_restore_early - Restore device using ACPI.
1270 * @dev: Device to restore.
1271 */
1272int acpi_subsys_restore_early(struct device *dev)
1273{
1274 int ret = acpi_dev_resume(dev);
1275
1276 return ret ? ret : pm_generic_restore_early(dev);
1277}
1278EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);
1279
1280/**
1281 * acpi_subsys_poweroff - Run the device driver's poweroff callback.
1282 * @dev: Device to handle.
1283 *
1284 * Follow PCI and resume devices from runtime suspend before running their
1285 * system poweroff callbacks, unless the driver can cope with runtime-suspended
1286 * devices during system suspend and there are no ACPI-specific reasons for
1287 * resuming them.
1288 */
1289int acpi_subsys_poweroff(struct device *dev)
1290{
1291 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1292 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1293 pm_runtime_resume(dev);
1294
1295 return pm_generic_poweroff(dev);
1296}
1297EXPORT_SYMBOL_GPL(acpi_subsys_poweroff);
1298
1299/**
1300 * acpi_subsys_poweroff_late - Run the device driver's poweroff callback.
1301 * @dev: Device to handle.
1302 *
1303 * Carry out the generic late poweroff procedure for @dev and use ACPI to put
1304 * it into a low-power state during system transition into a sleep state.
1305 */
1306static int acpi_subsys_poweroff_late(struct device *dev)
1307{
1308 int ret;
1309
1310 if (dev_pm_skip_suspend(dev))
1311 return 0;
1312
1313 ret = pm_generic_poweroff_late(dev);
1314 if (ret)
1315 return ret;
1316
1317 return acpi_dev_suspend(dev, device_may_wakeup(dev));
1318}
1319
1320/**
1321 * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.
1322 * @dev: Device to suspend.
1323 */
1324static int acpi_subsys_poweroff_noirq(struct device *dev)
1325{
1326 if (dev_pm_skip_suspend(dev))
1327 return 0;
1328
1329 return pm_generic_poweroff_noirq(dev);
1330}
1331#endif /* CONFIG_PM_SLEEP */
1332
1333static struct dev_pm_domain acpi_general_pm_domain = {
1334 .ops = {
1335 .runtime_suspend = acpi_subsys_runtime_suspend,
1336 .runtime_resume = acpi_subsys_runtime_resume,
1337#ifdef CONFIG_PM_SLEEP
1338 .prepare = acpi_subsys_prepare,
1339 .complete = acpi_subsys_complete,
1340 .suspend = acpi_subsys_suspend,
1341 .resume = acpi_subsys_resume,
1342 .suspend_late = acpi_subsys_suspend_late,
1343 .suspend_noirq = acpi_subsys_suspend_noirq,
1344 .resume_noirq = acpi_subsys_resume_noirq,
1345 .resume_early = acpi_subsys_resume_early,
1346 .freeze = acpi_subsys_freeze,
1347 .poweroff = acpi_subsys_poweroff,
1348 .poweroff_late = acpi_subsys_poweroff_late,
1349 .poweroff_noirq = acpi_subsys_poweroff_noirq,
1350 .restore_early = acpi_subsys_restore_early,
1351#endif
1352 },
1353};
1354
1355/**
1356 * acpi_dev_pm_detach - Remove ACPI power management from the device.
1357 * @dev: Device to take care of.
1358 * @power_off: Whether or not to try to remove power from the device.
1359 *
1360 * Remove the device from the general ACPI PM domain and remove its wakeup
1361 * notifier. If @power_off is set, additionally remove power from the device if
1362 * possible.
1363 *
1364 * Callers must ensure proper synchronization of this function with power
1365 * management callbacks.
1366 */
1367static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1368{
1369 struct acpi_device *adev = ACPI_COMPANION(dev);
1370
1371 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1372 dev_pm_domain_set(dev, NULL);
1373 acpi_remove_pm_notifier(adev);
1374 if (power_off) {
1375 /*
1376 * If the device's PM QoS resume latency limit or flags
1377 * have been exposed to user space, they have to be
1378 * hidden at this point, so that they don't affect the
1379 * choice of the low-power state to put the device into.
1380 */
1381 dev_pm_qos_hide_latency_limit(dev);
1382 dev_pm_qos_hide_flags(dev);
1383 acpi_device_wakeup_disable(adev);
1384 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1385 }
1386 }
1387}
1388
1389/**
1390 * acpi_dev_pm_attach - Prepare device for ACPI power management.
1391 * @dev: Device to prepare.
1392 * @power_on: Whether or not to power on the device.
1393 *
1394 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1395 * attached to it, install a wakeup notification handler for the device and
1396 * add it to the general ACPI PM domain. If @power_on is set, the device will
1397 * be put into the ACPI D0 state before the function returns.
1398 *
1399 * This assumes that the @dev's bus type uses generic power management callbacks
1400 * (or doesn't use any power management callbacks at all).
1401 *
1402 * Callers must ensure proper synchronization of this function with power
1403 * management callbacks.
1404 */
1405int acpi_dev_pm_attach(struct device *dev, bool power_on)
1406{
1407 /*
1408 * Skip devices whose ACPI companions match the device IDs below,
1409 * because they require special power management handling incompatible
1410 * with the generic ACPI PM domain.
1411 */
1412 static const struct acpi_device_id special_pm_ids[] = {
1413 ACPI_FAN_DEVICE_IDS,
1414 {}
1415 };
1416 struct acpi_device *adev = ACPI_COMPANION(dev);
1417
1418 if (!adev || !acpi_match_device_ids(adev, special_pm_ids))
1419 return 0;
1420
1421 /*
1422 * Only attach the power domain to the first device if the
1423 * companion is shared by multiple. This is to prevent doing power
1424 * management twice.
1425 */
1426 if (!acpi_device_is_first_physical_node(adev, dev))
1427 return 0;
1428
1429 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1430 dev_pm_domain_set(dev, &acpi_general_pm_domain);
1431 if (power_on) {
1432 acpi_dev_pm_full_power(adev);
1433 acpi_device_wakeup_disable(adev);
1434 }
1435
1436 dev->pm_domain->detach = acpi_dev_pm_detach;
1437 return 1;
1438}
1439EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1440
1441/**
1442 * acpi_storage_d3 - Check if D3 should be used in the suspend path
1443 * @dev: Device to check
1444 *
1445 * Return %true if the platform firmware wants @dev to be programmed
1446 * into D3hot or D3cold (if supported) in the suspend path, or %false
1447 * when there is no specific preference. On some platforms, if this
1448 * hint is ignored, @dev may remain unresponsive after suspending the
1449 * platform as a whole.
1450 *
1451 * Although the property has storage in the name it actually is
1452 * applied to the PCIe slot and plugging in a non-storage device the
1453 * same platform restrictions will likely apply.
1454 */
1455bool acpi_storage_d3(struct device *dev)
1456{
1457 struct acpi_device *adev = ACPI_COMPANION(dev);
1458 u8 val;
1459
1460 if (force_storage_d3())
1461 return true;
1462
1463 if (!adev)
1464 return false;
1465 if (fwnode_property_read_u8(acpi_fwnode_handle(adev), "StorageD3Enable",
1466 &val))
1467 return false;
1468 return val == 1;
1469}
1470EXPORT_SYMBOL_GPL(acpi_storage_d3);
1471
1472/**
1473 * acpi_dev_state_d0 - Tell if the device is in D0 power state
1474 * @dev: Physical device the ACPI power state of which to check
1475 *
1476 * On a system without ACPI, return true. On a system with ACPI, return true if
1477 * the current ACPI power state of the device is D0, or false otherwise.
1478 *
1479 * Note that the power state of a device is not well-defined after it has been
1480 * passed to acpi_device_set_power() and before that function returns, so it is
1481 * not valid to ask for the ACPI power state of the device in that time frame.
1482 *
1483 * This function is intended to be used in a driver's probe or remove
1484 * function. See Documentation/firmware-guide/acpi/non-d0-probe.rst for
1485 * more information.
1486 */
1487bool acpi_dev_state_d0(struct device *dev)
1488{
1489 struct acpi_device *adev = ACPI_COMPANION(dev);
1490
1491 if (!adev)
1492 return true;
1493
1494 return adev->power.state == ACPI_STATE_D0;
1495}
1496EXPORT_SYMBOL_GPL(acpi_dev_state_d0);
1497
1498#endif /* CONFIG_PM */