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#include <linux/suspend.h>
28
29#include "internal.h"
30
31#define _COMPONENT ACPI_POWER_COMPONENT
32ACPI_MODULE_NAME("device_pm");
33
34/**
35 * acpi_power_state_string - String representation of ACPI device power state.
36 * @state: ACPI device power state to return the string representation of.
37 */
38const char *acpi_power_state_string(int state)
39{
40 switch (state) {
41 case ACPI_STATE_D0:
42 return "D0";
43 case ACPI_STATE_D1:
44 return "D1";
45 case ACPI_STATE_D2:
46 return "D2";
47 case ACPI_STATE_D3_HOT:
48 return "D3hot";
49 case ACPI_STATE_D3_COLD:
50 return "D3cold";
51 default:
52 return "(unknown)";
53 }
54}
55
56/**
57 * acpi_device_get_power - Get power state of an ACPI device.
58 * @device: Device to get the power state of.
59 * @state: Place to store the power state of the device.
60 *
61 * This function does not update the device's power.state field, but it may
62 * update its parent's power.state field (when the parent's power state is
63 * unknown and the device's power state turns out to be D0).
64 */
65int acpi_device_get_power(struct acpi_device *device, int *state)
66{
67 int result = ACPI_STATE_UNKNOWN;
68
69 if (!device || !state)
70 return -EINVAL;
71
72 if (!device->flags.power_manageable) {
73 /* TBD: Non-recursive algorithm for walking up hierarchy. */
74 *state = device->parent ?
75 device->parent->power.state : ACPI_STATE_D0;
76 goto out;
77 }
78
79 /*
80 * Get the device's power state from power resources settings and _PSC,
81 * if available.
82 */
83 if (device->power.flags.power_resources) {
84 int error = acpi_power_get_inferred_state(device, &result);
85 if (error)
86 return error;
87 }
88 if (device->power.flags.explicit_get) {
89 acpi_handle handle = device->handle;
90 unsigned long long psc;
91 acpi_status status;
92
93 status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
94 if (ACPI_FAILURE(status))
95 return -ENODEV;
96
97 /*
98 * The power resources settings may indicate a power state
99 * shallower than the actual power state of the device, because
100 * the same power resources may be referenced by other devices.
101 *
102 * For systems predating ACPI 4.0 we assume that D3hot is the
103 * deepest state that can be supported.
104 */
105 if (psc > result && psc < ACPI_STATE_D3_COLD)
106 result = psc;
107 else if (result == ACPI_STATE_UNKNOWN)
108 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
109 }
110
111 /*
112 * If we were unsure about the device parent's power state up to this
113 * point, the fact that the device is in D0 implies that the parent has
114 * to be in D0 too, except if ignore_parent is set.
115 */
116 if (!device->power.flags.ignore_parent && device->parent
117 && device->parent->power.state == ACPI_STATE_UNKNOWN
118 && result == ACPI_STATE_D0)
119 device->parent->power.state = ACPI_STATE_D0;
120
121 *state = result;
122
123 out:
124 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
125 device->pnp.bus_id, acpi_power_state_string(*state)));
126
127 return 0;
128}
129EXPORT_SYMBOL(acpi_device_get_power);
130
131static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
132{
133 if (adev->power.states[state].flags.explicit_set) {
134 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
135 acpi_status status;
136
137 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
138 if (ACPI_FAILURE(status))
139 return -ENODEV;
140 }
141 return 0;
142}
143
144/**
145 * acpi_device_set_power - Set power state of an ACPI device.
146 * @device: Device to set the power state of.
147 * @state: New power state to set.
148 *
149 * Callers must ensure that the device is power manageable before using this
150 * function.
151 */
152int acpi_device_set_power(struct acpi_device *device, int state)
153{
154 int target_state = state;
155 int result = 0;
156
157 if (!device || !device->flags.power_manageable
158 || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
159 return -EINVAL;
160
161 /* Make sure this is a valid target state */
162
163 if (state == device->power.state) {
164 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
165 device->pnp.bus_id,
166 acpi_power_state_string(state)));
167 return 0;
168 }
169
170 if (state == ACPI_STATE_D3_COLD) {
171 /*
172 * For transitions to D3cold we need to execute _PS3 and then
173 * possibly drop references to the power resources in use.
174 */
175 state = ACPI_STATE_D3_HOT;
176 /* If _PR3 is not available, use D3hot as the target state. */
177 if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
178 target_state = state;
179 } else if (!device->power.states[state].flags.valid) {
180 dev_warn(&device->dev, "Power state %s not supported\n",
181 acpi_power_state_string(state));
182 return -ENODEV;
183 }
184
185 if (!device->power.flags.ignore_parent &&
186 device->parent && (state < device->parent->power.state)) {
187 dev_warn(&device->dev,
188 "Cannot transition to power state %s for parent in %s\n",
189 acpi_power_state_string(state),
190 acpi_power_state_string(device->parent->power.state));
191 return -ENODEV;
192 }
193
194 /*
195 * Transition Power
196 * ----------------
197 * In accordance with ACPI 6, _PSx is executed before manipulating power
198 * resources, unless the target state is D0, in which case _PS0 is
199 * supposed to be executed after turning the power resources on.
200 */
201 if (state > ACPI_STATE_D0) {
202 /*
203 * According to ACPI 6, devices cannot go from lower-power
204 * (deeper) states to higher-power (shallower) states.
205 */
206 if (state < device->power.state) {
207 dev_warn(&device->dev, "Cannot transition from %s to %s\n",
208 acpi_power_state_string(device->power.state),
209 acpi_power_state_string(state));
210 return -ENODEV;
211 }
212
213 result = acpi_dev_pm_explicit_set(device, state);
214 if (result)
215 goto end;
216
217 if (device->power.flags.power_resources)
218 result = acpi_power_transition(device, target_state);
219 } else {
220 if (device->power.flags.power_resources) {
221 result = acpi_power_transition(device, ACPI_STATE_D0);
222 if (result)
223 goto end;
224 }
225 result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
226 }
227
228 end:
229 if (result) {
230 dev_warn(&device->dev, "Failed to change power state to %s\n",
231 acpi_power_state_string(state));
232 } else {
233 device->power.state = target_state;
234 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
235 "Device [%s] transitioned to %s\n",
236 device->pnp.bus_id,
237 acpi_power_state_string(state)));
238 }
239
240 return result;
241}
242EXPORT_SYMBOL(acpi_device_set_power);
243
244int acpi_bus_set_power(acpi_handle handle, int state)
245{
246 struct acpi_device *device;
247 int result;
248
249 result = acpi_bus_get_device(handle, &device);
250 if (result)
251 return result;
252
253 return acpi_device_set_power(device, state);
254}
255EXPORT_SYMBOL(acpi_bus_set_power);
256
257int acpi_bus_init_power(struct acpi_device *device)
258{
259 int state;
260 int result;
261
262 if (!device)
263 return -EINVAL;
264
265 device->power.state = ACPI_STATE_UNKNOWN;
266 if (!acpi_device_is_present(device)) {
267 device->flags.initialized = false;
268 return -ENXIO;
269 }
270
271 result = acpi_device_get_power(device, &state);
272 if (result)
273 return result;
274
275 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
276 /* Reference count the power resources. */
277 result = acpi_power_on_resources(device, state);
278 if (result)
279 return result;
280
281 if (state == ACPI_STATE_D0) {
282 /*
283 * If _PSC is not present and the state inferred from
284 * power resources appears to be D0, it still may be
285 * necessary to execute _PS0 at this point, because
286 * another device using the same power resources may
287 * have been put into D0 previously and that's why we
288 * see D0 here.
289 */
290 result = acpi_dev_pm_explicit_set(device, state);
291 if (result)
292 return result;
293 }
294 } else if (state == ACPI_STATE_UNKNOWN) {
295 /*
296 * No power resources and missing _PSC? Cross fingers and make
297 * it D0 in hope that this is what the BIOS put the device into.
298 * [We tried to force D0 here by executing _PS0, but that broke
299 * Toshiba P870-303 in a nasty way.]
300 */
301 state = ACPI_STATE_D0;
302 }
303 device->power.state = state;
304 return 0;
305}
306
307/**
308 * acpi_device_fix_up_power - Force device with missing _PSC into D0.
309 * @device: Device object whose power state is to be fixed up.
310 *
311 * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
312 * are assumed to be put into D0 by the BIOS. However, in some cases that may
313 * not be the case and this function should be used then.
314 */
315int acpi_device_fix_up_power(struct acpi_device *device)
316{
317 int ret = 0;
318
319 if (!device->power.flags.power_resources
320 && !device->power.flags.explicit_get
321 && device->power.state == ACPI_STATE_D0)
322 ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
323
324 return ret;
325}
326EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);
327
328int acpi_device_update_power(struct acpi_device *device, int *state_p)
329{
330 int state;
331 int result;
332
333 if (device->power.state == ACPI_STATE_UNKNOWN) {
334 result = acpi_bus_init_power(device);
335 if (!result && state_p)
336 *state_p = device->power.state;
337
338 return result;
339 }
340
341 result = acpi_device_get_power(device, &state);
342 if (result)
343 return result;
344
345 if (state == ACPI_STATE_UNKNOWN) {
346 state = ACPI_STATE_D0;
347 result = acpi_device_set_power(device, state);
348 if (result)
349 return result;
350 } else {
351 if (device->power.flags.power_resources) {
352 /*
353 * We don't need to really switch the state, bu we need
354 * to update the power resources' reference counters.
355 */
356 result = acpi_power_transition(device, state);
357 if (result)
358 return result;
359 }
360 device->power.state = state;
361 }
362 if (state_p)
363 *state_p = state;
364
365 return 0;
366}
367EXPORT_SYMBOL_GPL(acpi_device_update_power);
368
369int acpi_bus_update_power(acpi_handle handle, int *state_p)
370{
371 struct acpi_device *device;
372 int result;
373
374 result = acpi_bus_get_device(handle, &device);
375 return result ? result : acpi_device_update_power(device, state_p);
376}
377EXPORT_SYMBOL_GPL(acpi_bus_update_power);
378
379bool acpi_bus_power_manageable(acpi_handle handle)
380{
381 struct acpi_device *device;
382 int result;
383
384 result = acpi_bus_get_device(handle, &device);
385 return result ? false : device->flags.power_manageable;
386}
387EXPORT_SYMBOL(acpi_bus_power_manageable);
388
389#ifdef CONFIG_PM
390static DEFINE_MUTEX(acpi_pm_notifier_lock);
391static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
392
393void acpi_pm_wakeup_event(struct device *dev)
394{
395 pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
396}
397EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
398
399static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
400{
401 struct acpi_device *adev;
402
403 if (val != ACPI_NOTIFY_DEVICE_WAKE)
404 return;
405
406 acpi_handle_debug(handle, "Wake notify\n");
407
408 adev = acpi_bus_get_acpi_device(handle);
409 if (!adev)
410 return;
411
412 mutex_lock(&acpi_pm_notifier_lock);
413
414 if (adev->wakeup.flags.notifier_present) {
415 pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
416 if (adev->wakeup.context.func) {
417 acpi_handle_debug(handle, "Running %pF for %s\n",
418 adev->wakeup.context.func,
419 dev_name(adev->wakeup.context.dev));
420 adev->wakeup.context.func(&adev->wakeup.context);
421 }
422 }
423
424 mutex_unlock(&acpi_pm_notifier_lock);
425
426 acpi_bus_put_acpi_device(adev);
427}
428
429/**
430 * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
431 * @adev: ACPI device to add the notify handler for.
432 * @dev: Device to generate a wakeup event for while handling the notification.
433 * @func: Work function to execute when handling the notification.
434 *
435 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
436 * PM wakeup events. For example, wakeup events may be generated for bridges
437 * if one of the devices below the bridge is signaling wakeup, even if the
438 * bridge itself doesn't have a wakeup GPE associated with it.
439 */
440acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
441 void (*func)(struct acpi_device_wakeup_context *context))
442{
443 acpi_status status = AE_ALREADY_EXISTS;
444
445 if (!dev && !func)
446 return AE_BAD_PARAMETER;
447
448 mutex_lock(&acpi_pm_notifier_install_lock);
449
450 if (adev->wakeup.flags.notifier_present)
451 goto out;
452
453 status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
454 acpi_pm_notify_handler, NULL);
455 if (ACPI_FAILURE(status))
456 goto out;
457
458 mutex_lock(&acpi_pm_notifier_lock);
459 adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
460 adev->wakeup.context.dev = dev;
461 adev->wakeup.context.func = func;
462 adev->wakeup.flags.notifier_present = true;
463 mutex_unlock(&acpi_pm_notifier_lock);
464
465 out:
466 mutex_unlock(&acpi_pm_notifier_install_lock);
467 return status;
468}
469
470/**
471 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
472 * @adev: ACPI device to remove the notifier from.
473 */
474acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
475{
476 acpi_status status = AE_BAD_PARAMETER;
477
478 mutex_lock(&acpi_pm_notifier_install_lock);
479
480 if (!adev->wakeup.flags.notifier_present)
481 goto out;
482
483 status = acpi_remove_notify_handler(adev->handle,
484 ACPI_SYSTEM_NOTIFY,
485 acpi_pm_notify_handler);
486 if (ACPI_FAILURE(status))
487 goto out;
488
489 mutex_lock(&acpi_pm_notifier_lock);
490 adev->wakeup.context.func = NULL;
491 adev->wakeup.context.dev = NULL;
492 wakeup_source_unregister(adev->wakeup.ws);
493 adev->wakeup.flags.notifier_present = false;
494 mutex_unlock(&acpi_pm_notifier_lock);
495
496 out:
497 mutex_unlock(&acpi_pm_notifier_install_lock);
498 return status;
499}
500
501bool acpi_bus_can_wakeup(acpi_handle handle)
502{
503 struct acpi_device *device;
504 int result;
505
506 result = acpi_bus_get_device(handle, &device);
507 return result ? false : device->wakeup.flags.valid;
508}
509EXPORT_SYMBOL(acpi_bus_can_wakeup);
510
511bool acpi_pm_device_can_wakeup(struct device *dev)
512{
513 struct acpi_device *adev = ACPI_COMPANION(dev);
514
515 return adev ? acpi_device_can_wakeup(adev) : false;
516}
517
518/**
519 * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
520 * @dev: Device whose preferred target power state to return.
521 * @adev: ACPI device node corresponding to @dev.
522 * @target_state: System state to match the resultant device state.
523 * @d_min_p: Location to store the highest power state available to the device.
524 * @d_max_p: Location to store the lowest power state available to the device.
525 *
526 * Find the lowest power (highest number) and highest power (lowest number) ACPI
527 * device power states that the device can be in while the system is in the
528 * state represented by @target_state. Store the integer numbers representing
529 * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
530 * respectively.
531 *
532 * Callers must ensure that @dev and @adev are valid pointers and that @adev
533 * actually corresponds to @dev before using this function.
534 *
535 * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
536 * returns a value that doesn't make sense. The memory locations pointed to by
537 * @d_max_p and @d_min_p are only modified on success.
538 */
539static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
540 u32 target_state, int *d_min_p, int *d_max_p)
541{
542 char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
543 acpi_handle handle = adev->handle;
544 unsigned long long ret;
545 int d_min, d_max;
546 bool wakeup = false;
547 bool has_sxd = false;
548 acpi_status status;
549
550 /*
551 * If the system state is S0, the lowest power state the device can be
552 * in is D3cold, unless the device has _S0W and is supposed to signal
553 * wakeup, in which case the return value of _S0W has to be used as the
554 * lowest power state available to the device.
555 */
556 d_min = ACPI_STATE_D0;
557 d_max = ACPI_STATE_D3_COLD;
558
559 /*
560 * If present, _SxD methods return the minimum D-state (highest power
561 * state) we can use for the corresponding S-states. Otherwise, the
562 * minimum D-state is D0 (ACPI 3.x).
563 */
564 if (target_state > ACPI_STATE_S0) {
565 /*
566 * We rely on acpi_evaluate_integer() not clobbering the integer
567 * provided if AE_NOT_FOUND is returned.
568 */
569 ret = d_min;
570 status = acpi_evaluate_integer(handle, method, NULL, &ret);
571 if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
572 || ret > ACPI_STATE_D3_COLD)
573 return -ENODATA;
574
575 /*
576 * We need to handle legacy systems where D3hot and D3cold are
577 * the same and 3 is returned in both cases, so fall back to
578 * D3cold if D3hot is not a valid state.
579 */
580 if (!adev->power.states[ret].flags.valid) {
581 if (ret == ACPI_STATE_D3_HOT)
582 ret = ACPI_STATE_D3_COLD;
583 else
584 return -ENODATA;
585 }
586
587 if (status == AE_OK)
588 has_sxd = true;
589
590 d_min = ret;
591 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
592 && adev->wakeup.sleep_state >= target_state;
593 } else {
594 wakeup = adev->wakeup.flags.valid;
595 }
596
597 /*
598 * If _PRW says we can wake up the system from the target sleep state,
599 * the D-state returned by _SxD is sufficient for that (we assume a
600 * wakeup-aware driver if wake is set). Still, if _SxW exists
601 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
602 * can wake the system. _S0W may be valid, too.
603 */
604 if (wakeup) {
605 method[3] = 'W';
606 status = acpi_evaluate_integer(handle, method, NULL, &ret);
607 if (status == AE_NOT_FOUND) {
608 /* No _SxW. In this case, the ACPI spec says that we
609 * must not go into any power state deeper than the
610 * value returned from _SxD.
611 */
612 if (has_sxd && target_state > ACPI_STATE_S0)
613 d_max = d_min;
614 } else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
615 /* Fall back to D3cold if ret is not a valid state. */
616 if (!adev->power.states[ret].flags.valid)
617 ret = ACPI_STATE_D3_COLD;
618
619 d_max = ret > d_min ? ret : d_min;
620 } else {
621 return -ENODATA;
622 }
623 }
624
625 if (d_min_p)
626 *d_min_p = d_min;
627
628 if (d_max_p)
629 *d_max_p = d_max;
630
631 return 0;
632}
633
634/**
635 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
636 * @dev: Device whose preferred target power state to return.
637 * @d_min_p: Location to store the upper limit of the allowed states range.
638 * @d_max_in: Deepest low-power state to take into consideration.
639 * Return value: Preferred power state of the device on success, -ENODEV
640 * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
641 * incorrect, or -ENODATA on ACPI method failure.
642 *
643 * The caller must ensure that @dev is valid before using this function.
644 */
645int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
646{
647 struct acpi_device *adev;
648 int ret, d_min, d_max;
649
650 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
651 return -EINVAL;
652
653 if (d_max_in > ACPI_STATE_D2) {
654 enum pm_qos_flags_status stat;
655
656 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
657 if (stat == PM_QOS_FLAGS_ALL)
658 d_max_in = ACPI_STATE_D2;
659 }
660
661 adev = ACPI_COMPANION(dev);
662 if (!adev) {
663 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
664 return -ENODEV;
665 }
666
667 ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
668 &d_min, &d_max);
669 if (ret)
670 return ret;
671
672 if (d_max_in < d_min)
673 return -EINVAL;
674
675 if (d_max > d_max_in) {
676 for (d_max = d_max_in; d_max > d_min; d_max--) {
677 if (adev->power.states[d_max].flags.valid)
678 break;
679 }
680 }
681
682 if (d_min_p)
683 *d_min_p = d_min;
684
685 return d_max;
686}
687EXPORT_SYMBOL(acpi_pm_device_sleep_state);
688
689/**
690 * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
691 * @context: Device wakeup context.
692 */
693static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
694{
695 struct device *dev = context->dev;
696
697 if (dev) {
698 pm_wakeup_event(dev, 0);
699 pm_request_resume(dev);
700 }
701}
702
703static DEFINE_MUTEX(acpi_wakeup_lock);
704
705static int __acpi_device_wakeup_enable(struct acpi_device *adev,
706 u32 target_state, int max_count)
707{
708 struct acpi_device_wakeup *wakeup = &adev->wakeup;
709 acpi_status status;
710 int error = 0;
711
712 mutex_lock(&acpi_wakeup_lock);
713
714 if (wakeup->enable_count >= max_count)
715 goto out;
716
717 if (wakeup->enable_count > 0)
718 goto inc;
719
720 error = acpi_enable_wakeup_device_power(adev, target_state);
721 if (error)
722 goto out;
723
724 status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
725 if (ACPI_FAILURE(status)) {
726 acpi_disable_wakeup_device_power(adev);
727 error = -EIO;
728 goto out;
729 }
730
731inc:
732 wakeup->enable_count++;
733
734out:
735 mutex_unlock(&acpi_wakeup_lock);
736 return error;
737}
738
739/**
740 * acpi_device_wakeup_enable - Enable wakeup functionality for device.
741 * @adev: ACPI device to enable wakeup functionality for.
742 * @target_state: State the system is transitioning into.
743 *
744 * Enable the GPE associated with @adev so that it can generate wakeup signals
745 * for the device in response to external (remote) events and enable wakeup
746 * power for it.
747 *
748 * Callers must ensure that @adev is a valid ACPI device node before executing
749 * this function.
750 */
751static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
752{
753 return __acpi_device_wakeup_enable(adev, target_state, 1);
754}
755
756/**
757 * acpi_device_wakeup_disable - Disable wakeup functionality for device.
758 * @adev: ACPI device to disable wakeup functionality for.
759 *
760 * Disable the GPE associated with @adev and disable wakeup power for it.
761 *
762 * Callers must ensure that @adev is a valid ACPI device node before executing
763 * this function.
764 */
765static void acpi_device_wakeup_disable(struct acpi_device *adev)
766{
767 struct acpi_device_wakeup *wakeup = &adev->wakeup;
768
769 mutex_lock(&acpi_wakeup_lock);
770
771 if (!wakeup->enable_count)
772 goto out;
773
774 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
775 acpi_disable_wakeup_device_power(adev);
776
777 wakeup->enable_count--;
778
779out:
780 mutex_unlock(&acpi_wakeup_lock);
781}
782
783static int __acpi_pm_set_device_wakeup(struct device *dev, bool enable,
784 int max_count)
785{
786 struct acpi_device *adev;
787 int error;
788
789 adev = ACPI_COMPANION(dev);
790 if (!adev) {
791 dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
792 return -ENODEV;
793 }
794
795 if (!acpi_device_can_wakeup(adev))
796 return -EINVAL;
797
798 if (!enable) {
799 acpi_device_wakeup_disable(adev);
800 dev_dbg(dev, "Wakeup disabled by ACPI\n");
801 return 0;
802 }
803
804 error = __acpi_device_wakeup_enable(adev, acpi_target_system_state(),
805 max_count);
806 if (!error)
807 dev_dbg(dev, "Wakeup enabled by ACPI\n");
808
809 return error;
810}
811
812/**
813 * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
814 * @dev: Device to enable/disable to generate wakeup events.
815 * @enable: Whether to enable or disable the wakeup functionality.
816 */
817int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
818{
819 return __acpi_pm_set_device_wakeup(dev, enable, 1);
820}
821EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
822
823/**
824 * acpi_pm_set_bridge_wakeup - Enable/disable remote wakeup for given bridge.
825 * @dev: Bridge device to enable/disable to generate wakeup events.
826 * @enable: Whether to enable or disable the wakeup functionality.
827 */
828int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable)
829{
830 return __acpi_pm_set_device_wakeup(dev, enable, INT_MAX);
831}
832EXPORT_SYMBOL_GPL(acpi_pm_set_bridge_wakeup);
833
834/**
835 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
836 * @dev: Device to put into a low-power state.
837 * @adev: ACPI device node corresponding to @dev.
838 * @system_state: System state to choose the device state for.
839 */
840static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
841 u32 system_state)
842{
843 int ret, state;
844
845 if (!acpi_device_power_manageable(adev))
846 return 0;
847
848 ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
849 return ret ? ret : acpi_device_set_power(adev, state);
850}
851
852/**
853 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
854 * @adev: ACPI device node to put into the full-power state.
855 */
856static int acpi_dev_pm_full_power(struct acpi_device *adev)
857{
858 return acpi_device_power_manageable(adev) ?
859 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
860}
861
862/**
863 * acpi_dev_suspend - Put device into a low-power state using ACPI.
864 * @dev: Device to put into a low-power state.
865 * @wakeup: Whether or not to enable wakeup for the device.
866 *
867 * Put the given device into a low-power state using the standard ACPI
868 * mechanism. Set up remote wakeup if desired, choose the state to put the
869 * device into (this checks if remote wakeup is expected to work too), and set
870 * the power state of the device.
871 */
872int acpi_dev_suspend(struct device *dev, bool wakeup)
873{
874 struct acpi_device *adev = ACPI_COMPANION(dev);
875 u32 target_state = acpi_target_system_state();
876 int error;
877
878 if (!adev)
879 return 0;
880
881 if (wakeup && acpi_device_can_wakeup(adev)) {
882 error = acpi_device_wakeup_enable(adev, target_state);
883 if (error)
884 return -EAGAIN;
885 } else {
886 wakeup = false;
887 }
888
889 error = acpi_dev_pm_low_power(dev, adev, target_state);
890 if (error && wakeup)
891 acpi_device_wakeup_disable(adev);
892
893 return error;
894}
895EXPORT_SYMBOL_GPL(acpi_dev_suspend);
896
897/**
898 * acpi_dev_resume - Put device into the full-power state using ACPI.
899 * @dev: Device to put into the full-power state.
900 *
901 * Put the given device into the full-power state using the standard ACPI
902 * mechanism. Set the power state of the device to ACPI D0 and disable wakeup.
903 */
904int acpi_dev_resume(struct device *dev)
905{
906 struct acpi_device *adev = ACPI_COMPANION(dev);
907 int error;
908
909 if (!adev)
910 return 0;
911
912 error = acpi_dev_pm_full_power(adev);
913 acpi_device_wakeup_disable(adev);
914 return error;
915}
916EXPORT_SYMBOL_GPL(acpi_dev_resume);
917
918/**
919 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
920 * @dev: Device to suspend.
921 *
922 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
923 * it into a runtime low-power state.
924 */
925int acpi_subsys_runtime_suspend(struct device *dev)
926{
927 int ret = pm_generic_runtime_suspend(dev);
928 return ret ? ret : acpi_dev_suspend(dev, true);
929}
930EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
931
932/**
933 * acpi_subsys_runtime_resume - Resume device using ACPI.
934 * @dev: Device to Resume.
935 *
936 * Use ACPI to put the given device into the full-power state and carry out the
937 * generic runtime resume procedure for it.
938 */
939int acpi_subsys_runtime_resume(struct device *dev)
940{
941 int ret = acpi_dev_resume(dev);
942 return ret ? ret : pm_generic_runtime_resume(dev);
943}
944EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
945
946#ifdef CONFIG_PM_SLEEP
947static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
948{
949 u32 sys_target = acpi_target_system_state();
950 int ret, state;
951
952 if (!pm_runtime_suspended(dev) || !adev ||
953 device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
954 return true;
955
956 if (sys_target == ACPI_STATE_S0)
957 return false;
958
959 if (adev->power.flags.dsw_present)
960 return true;
961
962 ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
963 if (ret)
964 return true;
965
966 return state != adev->power.state;
967}
968
969/**
970 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
971 * @dev: Device to prepare.
972 */
973int acpi_subsys_prepare(struct device *dev)
974{
975 struct acpi_device *adev = ACPI_COMPANION(dev);
976
977 if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
978 int ret = dev->driver->pm->prepare(dev);
979
980 if (ret < 0)
981 return ret;
982
983 if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
984 return 0;
985 }
986
987 return !acpi_dev_needs_resume(dev, adev);
988}
989EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
990
991/**
992 * acpi_subsys_complete - Finalize device's resume during system resume.
993 * @dev: Device to handle.
994 */
995void acpi_subsys_complete(struct device *dev)
996{
997 pm_generic_complete(dev);
998 /*
999 * If the device had been runtime-suspended before the system went into
1000 * the sleep state it is going out of and it has never been resumed till
1001 * now, resume it in case the firmware powered it up.
1002 */
1003 if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
1004 pm_request_resume(dev);
1005}
1006EXPORT_SYMBOL_GPL(acpi_subsys_complete);
1007
1008/**
1009 * acpi_subsys_suspend - Run the device driver's suspend callback.
1010 * @dev: Device to handle.
1011 *
1012 * Follow PCI and resume devices from runtime suspend before running their
1013 * system suspend callbacks, unless the driver can cope with runtime-suspended
1014 * devices during system suspend and there are no ACPI-specific reasons for
1015 * resuming them.
1016 */
1017int acpi_subsys_suspend(struct device *dev)
1018{
1019 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
1020 acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
1021 pm_runtime_resume(dev);
1022
1023 return pm_generic_suspend(dev);
1024}
1025EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
1026
1027/**
1028 * acpi_subsys_suspend_late - Suspend device using ACPI.
1029 * @dev: Device to suspend.
1030 *
1031 * Carry out the generic late suspend procedure for @dev and use ACPI to put
1032 * it into a low-power state during system transition into a sleep state.
1033 */
1034int acpi_subsys_suspend_late(struct device *dev)
1035{
1036 int ret;
1037
1038 if (dev_pm_smart_suspend_and_suspended(dev))
1039 return 0;
1040
1041 ret = pm_generic_suspend_late(dev);
1042 return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
1043}
1044EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
1045
1046/**
1047 * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
1048 * @dev: Device to suspend.
1049 */
1050int acpi_subsys_suspend_noirq(struct device *dev)
1051{
1052 int ret;
1053
1054 if (dev_pm_smart_suspend_and_suspended(dev)) {
1055 dev->power.may_skip_resume = true;
1056 return 0;
1057 }
1058
1059 ret = pm_generic_suspend_noirq(dev);
1060 if (ret)
1061 return ret;
1062
1063 /*
1064 * If the target system sleep state is suspend-to-idle, it is sufficient
1065 * to check whether or not the device's wakeup settings are good for
1066 * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
1067 * acpi_subsys_complete() to take care of fixing up the device's state
1068 * anyway, if need be.
1069 */
1070 dev->power.may_skip_resume = device_may_wakeup(dev) ||
1071 !device_can_wakeup(dev);
1072
1073 return 0;
1074}
1075EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
1076
1077/**
1078 * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
1079 * @dev: Device to handle.
1080 */
1081int acpi_subsys_resume_noirq(struct device *dev)
1082{
1083 if (dev_pm_may_skip_resume(dev))
1084 return 0;
1085
1086 /*
1087 * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend
1088 * during system suspend, so update their runtime PM status to "active"
1089 * as they will be put into D0 going forward.
1090 */
1091 if (dev_pm_smart_suspend_and_suspended(dev))
1092 pm_runtime_set_active(dev);
1093
1094 return pm_generic_resume_noirq(dev);
1095}
1096EXPORT_SYMBOL_GPL(acpi_subsys_resume_noirq);
1097
1098/**
1099 * acpi_subsys_resume_early - Resume device using ACPI.
1100 * @dev: Device to Resume.
1101 *
1102 * Use ACPI to put the given device into the full-power state and carry out the
1103 * generic early resume procedure for it during system transition into the
1104 * working state.
1105 */
1106int acpi_subsys_resume_early(struct device *dev)
1107{
1108 int ret = acpi_dev_resume(dev);
1109 return ret ? ret : pm_generic_resume_early(dev);
1110}
1111EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
1112
1113/**
1114 * acpi_subsys_freeze - Run the device driver's freeze callback.
1115 * @dev: Device to handle.
1116 */
1117int acpi_subsys_freeze(struct device *dev)
1118{
1119 /*
1120 * This used to be done in acpi_subsys_prepare() for all devices and
1121 * some drivers may depend on it, so do it here. Ideally, however,
1122 * runtime-suspended devices should not be touched during freeze/thaw
1123 * transitions.
1124 */
1125 if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND))
1126 pm_runtime_resume(dev);
1127
1128 return pm_generic_freeze(dev);
1129}
1130EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
1131
1132/**
1133 * acpi_subsys_freeze_late - Run the device driver's "late" freeze callback.
1134 * @dev: Device to handle.
1135 */
1136int acpi_subsys_freeze_late(struct device *dev)
1137{
1138
1139 if (dev_pm_smart_suspend_and_suspended(dev))
1140 return 0;
1141
1142 return pm_generic_freeze_late(dev);
1143}
1144EXPORT_SYMBOL_GPL(acpi_subsys_freeze_late);
1145
1146/**
1147 * acpi_subsys_freeze_noirq - Run the device driver's "noirq" freeze callback.
1148 * @dev: Device to handle.
1149 */
1150int acpi_subsys_freeze_noirq(struct device *dev)
1151{
1152
1153 if (dev_pm_smart_suspend_and_suspended(dev))
1154 return 0;
1155
1156 return pm_generic_freeze_noirq(dev);
1157}
1158EXPORT_SYMBOL_GPL(acpi_subsys_freeze_noirq);
1159
1160/**
1161 * acpi_subsys_thaw_noirq - Run the device driver's "noirq" thaw callback.
1162 * @dev: Device to handle.
1163 */
1164int acpi_subsys_thaw_noirq(struct device *dev)
1165{
1166 /*
1167 * If the device is in runtime suspend, the "thaw" code may not work
1168 * correctly with it, so skip the driver callback and make the PM core
1169 * skip all of the subsequent "thaw" callbacks for the device.
1170 */
1171 if (dev_pm_smart_suspend_and_suspended(dev)) {
1172 dev_pm_skip_next_resume_phases(dev);
1173 return 0;
1174 }
1175
1176 return pm_generic_thaw_noirq(dev);
1177}
1178EXPORT_SYMBOL_GPL(acpi_subsys_thaw_noirq);
1179#endif /* CONFIG_PM_SLEEP */
1180
1181static struct dev_pm_domain acpi_general_pm_domain = {
1182 .ops = {
1183 .runtime_suspend = acpi_subsys_runtime_suspend,
1184 .runtime_resume = acpi_subsys_runtime_resume,
1185#ifdef CONFIG_PM_SLEEP
1186 .prepare = acpi_subsys_prepare,
1187 .complete = acpi_subsys_complete,
1188 .suspend = acpi_subsys_suspend,
1189 .suspend_late = acpi_subsys_suspend_late,
1190 .suspend_noirq = acpi_subsys_suspend_noirq,
1191 .resume_noirq = acpi_subsys_resume_noirq,
1192 .resume_early = acpi_subsys_resume_early,
1193 .freeze = acpi_subsys_freeze,
1194 .freeze_late = acpi_subsys_freeze_late,
1195 .freeze_noirq = acpi_subsys_freeze_noirq,
1196 .thaw_noirq = acpi_subsys_thaw_noirq,
1197 .poweroff = acpi_subsys_suspend,
1198 .poweroff_late = acpi_subsys_suspend_late,
1199 .poweroff_noirq = acpi_subsys_suspend_noirq,
1200 .restore_noirq = acpi_subsys_resume_noirq,
1201 .restore_early = acpi_subsys_resume_early,
1202#endif
1203 },
1204};
1205
1206/**
1207 * acpi_dev_pm_detach - Remove ACPI power management from the device.
1208 * @dev: Device to take care of.
1209 * @power_off: Whether or not to try to remove power from the device.
1210 *
1211 * Remove the device from the general ACPI PM domain and remove its wakeup
1212 * notifier. If @power_off is set, additionally remove power from the device if
1213 * possible.
1214 *
1215 * Callers must ensure proper synchronization of this function with power
1216 * management callbacks.
1217 */
1218static void acpi_dev_pm_detach(struct device *dev, bool power_off)
1219{
1220 struct acpi_device *adev = ACPI_COMPANION(dev);
1221
1222 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
1223 dev_pm_domain_set(dev, NULL);
1224 acpi_remove_pm_notifier(adev);
1225 if (power_off) {
1226 /*
1227 * If the device's PM QoS resume latency limit or flags
1228 * have been exposed to user space, they have to be
1229 * hidden at this point, so that they don't affect the
1230 * choice of the low-power state to put the device into.
1231 */
1232 dev_pm_qos_hide_latency_limit(dev);
1233 dev_pm_qos_hide_flags(dev);
1234 acpi_device_wakeup_disable(adev);
1235 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
1236 }
1237 }
1238}
1239
1240/**
1241 * acpi_dev_pm_attach - Prepare device for ACPI power management.
1242 * @dev: Device to prepare.
1243 * @power_on: Whether or not to power on the device.
1244 *
1245 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
1246 * attached to it, install a wakeup notification handler for the device and
1247 * add it to the general ACPI PM domain. If @power_on is set, the device will
1248 * be put into the ACPI D0 state before the function returns.
1249 *
1250 * This assumes that the @dev's bus type uses generic power management callbacks
1251 * (or doesn't use any power management callbacks at all).
1252 *
1253 * Callers must ensure proper synchronization of this function with power
1254 * management callbacks.
1255 */
1256int acpi_dev_pm_attach(struct device *dev, bool power_on)
1257{
1258 struct acpi_device *adev = ACPI_COMPANION(dev);
1259
1260 if (!adev)
1261 return 0;
1262
1263 /*
1264 * Only attach the power domain to the first device if the
1265 * companion is shared by multiple. This is to prevent doing power
1266 * management twice.
1267 */
1268 if (!acpi_device_is_first_physical_node(adev, dev))
1269 return 0;
1270
1271 acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
1272 dev_pm_domain_set(dev, &acpi_general_pm_domain);
1273 if (power_on) {
1274 acpi_dev_pm_full_power(adev);
1275 acpi_device_wakeup_disable(adev);
1276 }
1277
1278 dev->pm_domain->detach = acpi_dev_pm_detach;
1279 return 1;
1280}
1281EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
1282#endif /* CONFIG_PM */
1283