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1/*
2 * drivers/acpi/power.c - ACPI Power Resources management.
3 *
4 * Copyright (C) 2001 - 2015 Intel Corp.
5 * Author: Andy Grover <andrew.grover@intel.com>
6 * Author: Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8 *
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or (at
14 * your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
20 *
21 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
22 */
23
24/*
25 * ACPI power-managed devices may be controlled in two ways:
26 * 1. via "Device Specific (D-State) Control"
27 * 2. via "Power Resource Control".
28 * The code below deals with ACPI Power Resources control.
29 *
30 * An ACPI "power resource object" represents a software controllable power
31 * plane, clock plane, or other resource depended on by a device.
32 *
33 * A device may rely on multiple power resources, and a power resource
34 * may be shared by multiple devices.
35 */
36
37#include <linux/kernel.h>
38#include <linux/module.h>
39#include <linux/init.h>
40#include <linux/types.h>
41#include <linux/slab.h>
42#include <linux/pm_runtime.h>
43#include <linux/sysfs.h>
44#include <linux/acpi.h>
45#include "sleep.h"
46#include "internal.h"
47
48#define _COMPONENT ACPI_POWER_COMPONENT
49ACPI_MODULE_NAME("power");
50#define ACPI_POWER_CLASS "power_resource"
51#define ACPI_POWER_DEVICE_NAME "Power Resource"
52#define ACPI_POWER_FILE_INFO "info"
53#define ACPI_POWER_FILE_STATUS "state"
54#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
55#define ACPI_POWER_RESOURCE_STATE_ON 0x01
56#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
57
58struct acpi_power_resource {
59 struct acpi_device device;
60 struct list_head list_node;
61 char *name;
62 u32 system_level;
63 u32 order;
64 unsigned int ref_count;
65 bool wakeup_enabled;
66 struct mutex resource_lock;
67};
68
69struct acpi_power_resource_entry {
70 struct list_head node;
71 struct acpi_power_resource *resource;
72};
73
74static LIST_HEAD(acpi_power_resource_list);
75static DEFINE_MUTEX(power_resource_list_lock);
76
77/* --------------------------------------------------------------------------
78 Power Resource Management
79 -------------------------------------------------------------------------- */
80
81static inline
82struct acpi_power_resource *to_power_resource(struct acpi_device *device)
83{
84 return container_of(device, struct acpi_power_resource, device);
85}
86
87static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
88{
89 struct acpi_device *device;
90
91 if (acpi_bus_get_device(handle, &device))
92 return NULL;
93
94 return to_power_resource(device);
95}
96
97static int acpi_power_resources_list_add(acpi_handle handle,
98 struct list_head *list)
99{
100 struct acpi_power_resource *resource = acpi_power_get_context(handle);
101 struct acpi_power_resource_entry *entry;
102
103 if (!resource || !list)
104 return -EINVAL;
105
106 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
107 if (!entry)
108 return -ENOMEM;
109
110 entry->resource = resource;
111 if (!list_empty(list)) {
112 struct acpi_power_resource_entry *e;
113
114 list_for_each_entry(e, list, node)
115 if (e->resource->order > resource->order) {
116 list_add_tail(&entry->node, &e->node);
117 return 0;
118 }
119 }
120 list_add_tail(&entry->node, list);
121 return 0;
122}
123
124void acpi_power_resources_list_free(struct list_head *list)
125{
126 struct acpi_power_resource_entry *entry, *e;
127
128 list_for_each_entry_safe(entry, e, list, node) {
129 list_del(&entry->node);
130 kfree(entry);
131 }
132}
133
134int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
135 struct list_head *list)
136{
137 unsigned int i;
138 int err = 0;
139
140 for (i = start; i < package->package.count; i++) {
141 union acpi_object *element = &package->package.elements[i];
142 acpi_handle rhandle;
143
144 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
145 err = -ENODATA;
146 break;
147 }
148 rhandle = element->reference.handle;
149 if (!rhandle) {
150 err = -ENODEV;
151 break;
152 }
153 err = acpi_add_power_resource(rhandle);
154 if (err)
155 break;
156
157 err = acpi_power_resources_list_add(rhandle, list);
158 if (err)
159 break;
160 }
161 if (err)
162 acpi_power_resources_list_free(list);
163
164 return err;
165}
166
167static int acpi_power_get_state(acpi_handle handle, int *state)
168{
169 acpi_status status = AE_OK;
170 unsigned long long sta = 0;
171 char node_name[5];
172 struct acpi_buffer buffer = { sizeof(node_name), node_name };
173
174
175 if (!handle || !state)
176 return -EINVAL;
177
178 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
179 if (ACPI_FAILURE(status))
180 return -ENODEV;
181
182 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
183 ACPI_POWER_RESOURCE_STATE_OFF;
184
185 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
186
187 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
188 node_name,
189 *state ? "on" : "off"));
190
191 return 0;
192}
193
194static int acpi_power_get_list_state(struct list_head *list, int *state)
195{
196 struct acpi_power_resource_entry *entry;
197 int cur_state;
198
199 if (!list || !state)
200 return -EINVAL;
201
202 /* The state of the list is 'on' IFF all resources are 'on'. */
203 list_for_each_entry(entry, list, node) {
204 struct acpi_power_resource *resource = entry->resource;
205 acpi_handle handle = resource->device.handle;
206 int result;
207
208 mutex_lock(&resource->resource_lock);
209 result = acpi_power_get_state(handle, &cur_state);
210 mutex_unlock(&resource->resource_lock);
211 if (result)
212 return result;
213
214 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
215 break;
216 }
217
218 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
219 cur_state ? "on" : "off"));
220
221 *state = cur_state;
222 return 0;
223}
224
225static int __acpi_power_on(struct acpi_power_resource *resource)
226{
227 acpi_status status = AE_OK;
228
229 status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL);
230 if (ACPI_FAILURE(status))
231 return -ENODEV;
232
233 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
234 resource->name));
235
236 return 0;
237}
238
239static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
240{
241 int result = 0;
242
243 if (resource->ref_count++) {
244 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
245 "Power resource [%s] already on\n",
246 resource->name));
247 } else {
248 result = __acpi_power_on(resource);
249 if (result)
250 resource->ref_count--;
251 }
252 return result;
253}
254
255static int acpi_power_on(struct acpi_power_resource *resource)
256{
257 int result;
258
259 mutex_lock(&resource->resource_lock);
260 result = acpi_power_on_unlocked(resource);
261 mutex_unlock(&resource->resource_lock);
262 return result;
263}
264
265static int __acpi_power_off(struct acpi_power_resource *resource)
266{
267 acpi_status status;
268
269 status = acpi_evaluate_object(resource->device.handle, "_OFF",
270 NULL, NULL);
271 if (ACPI_FAILURE(status))
272 return -ENODEV;
273
274 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned off\n",
275 resource->name));
276 return 0;
277}
278
279static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
280{
281 int result = 0;
282
283 if (!resource->ref_count) {
284 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
285 "Power resource [%s] already off\n",
286 resource->name));
287 return 0;
288 }
289
290 if (--resource->ref_count) {
291 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
292 "Power resource [%s] still in use\n",
293 resource->name));
294 } else {
295 result = __acpi_power_off(resource);
296 if (result)
297 resource->ref_count++;
298 }
299 return result;
300}
301
302static int acpi_power_off(struct acpi_power_resource *resource)
303{
304 int result;
305
306 mutex_lock(&resource->resource_lock);
307 result = acpi_power_off_unlocked(resource);
308 mutex_unlock(&resource->resource_lock);
309 return result;
310}
311
312static int acpi_power_off_list(struct list_head *list)
313{
314 struct acpi_power_resource_entry *entry;
315 int result = 0;
316
317 list_for_each_entry_reverse(entry, list, node) {
318 result = acpi_power_off(entry->resource);
319 if (result)
320 goto err;
321 }
322 return 0;
323
324 err:
325 list_for_each_entry_continue(entry, list, node)
326 acpi_power_on(entry->resource);
327
328 return result;
329}
330
331static int acpi_power_on_list(struct list_head *list)
332{
333 struct acpi_power_resource_entry *entry;
334 int result = 0;
335
336 list_for_each_entry(entry, list, node) {
337 result = acpi_power_on(entry->resource);
338 if (result)
339 goto err;
340 }
341 return 0;
342
343 err:
344 list_for_each_entry_continue_reverse(entry, list, node)
345 acpi_power_off(entry->resource);
346
347 return result;
348}
349
350static struct attribute *attrs[] = {
351 NULL,
352};
353
354static struct attribute_group attr_groups[] = {
355 [ACPI_STATE_D0] = {
356 .name = "power_resources_D0",
357 .attrs = attrs,
358 },
359 [ACPI_STATE_D1] = {
360 .name = "power_resources_D1",
361 .attrs = attrs,
362 },
363 [ACPI_STATE_D2] = {
364 .name = "power_resources_D2",
365 .attrs = attrs,
366 },
367 [ACPI_STATE_D3_HOT] = {
368 .name = "power_resources_D3hot",
369 .attrs = attrs,
370 },
371};
372
373static struct attribute_group wakeup_attr_group = {
374 .name = "power_resources_wakeup",
375 .attrs = attrs,
376};
377
378static void acpi_power_hide_list(struct acpi_device *adev,
379 struct list_head *resources,
380 struct attribute_group *attr_group)
381{
382 struct acpi_power_resource_entry *entry;
383
384 if (list_empty(resources))
385 return;
386
387 list_for_each_entry_reverse(entry, resources, node) {
388 struct acpi_device *res_dev = &entry->resource->device;
389
390 sysfs_remove_link_from_group(&adev->dev.kobj,
391 attr_group->name,
392 dev_name(&res_dev->dev));
393 }
394 sysfs_remove_group(&adev->dev.kobj, attr_group);
395}
396
397static void acpi_power_expose_list(struct acpi_device *adev,
398 struct list_head *resources,
399 struct attribute_group *attr_group)
400{
401 struct acpi_power_resource_entry *entry;
402 int ret;
403
404 if (list_empty(resources))
405 return;
406
407 ret = sysfs_create_group(&adev->dev.kobj, attr_group);
408 if (ret)
409 return;
410
411 list_for_each_entry(entry, resources, node) {
412 struct acpi_device *res_dev = &entry->resource->device;
413
414 ret = sysfs_add_link_to_group(&adev->dev.kobj,
415 attr_group->name,
416 &res_dev->dev.kobj,
417 dev_name(&res_dev->dev));
418 if (ret) {
419 acpi_power_hide_list(adev, resources, attr_group);
420 break;
421 }
422 }
423}
424
425static void acpi_power_expose_hide(struct acpi_device *adev,
426 struct list_head *resources,
427 struct attribute_group *attr_group,
428 bool expose)
429{
430 if (expose)
431 acpi_power_expose_list(adev, resources, attr_group);
432 else
433 acpi_power_hide_list(adev, resources, attr_group);
434}
435
436void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
437{
438 int state;
439
440 if (adev->wakeup.flags.valid)
441 acpi_power_expose_hide(adev, &adev->wakeup.resources,
442 &wakeup_attr_group, add);
443
444 if (!adev->power.flags.power_resources)
445 return;
446
447 for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
448 acpi_power_expose_hide(adev,
449 &adev->power.states[state].resources,
450 &attr_groups[state], add);
451}
452
453int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
454{
455 struct acpi_power_resource_entry *entry;
456 int system_level = 5;
457
458 list_for_each_entry(entry, list, node) {
459 struct acpi_power_resource *resource = entry->resource;
460 acpi_handle handle = resource->device.handle;
461 int result;
462 int state;
463
464 mutex_lock(&resource->resource_lock);
465
466 result = acpi_power_get_state(handle, &state);
467 if (result) {
468 mutex_unlock(&resource->resource_lock);
469 return result;
470 }
471 if (state == ACPI_POWER_RESOURCE_STATE_ON) {
472 resource->ref_count++;
473 resource->wakeup_enabled = true;
474 }
475 if (system_level > resource->system_level)
476 system_level = resource->system_level;
477
478 mutex_unlock(&resource->resource_lock);
479 }
480 *system_level_p = system_level;
481 return 0;
482}
483
484/* --------------------------------------------------------------------------
485 Device Power Management
486 -------------------------------------------------------------------------- */
487
488/**
489 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
490 * ACPI 3.0) _PSW (Power State Wake)
491 * @dev: Device to handle.
492 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
493 * @sleep_state: Target sleep state of the system.
494 * @dev_state: Target power state of the device.
495 *
496 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
497 * State Wake) for the device, if present. On failure reset the device's
498 * wakeup.flags.valid flag.
499 *
500 * RETURN VALUE:
501 * 0 if either _DSW or _PSW has been successfully executed
502 * 0 if neither _DSW nor _PSW has been found
503 * -ENODEV if the execution of either _DSW or _PSW has failed
504 */
505int acpi_device_sleep_wake(struct acpi_device *dev,
506 int enable, int sleep_state, int dev_state)
507{
508 union acpi_object in_arg[3];
509 struct acpi_object_list arg_list = { 3, in_arg };
510 acpi_status status = AE_OK;
511
512 /*
513 * Try to execute _DSW first.
514 *
515 * Three agruments are needed for the _DSW object:
516 * Argument 0: enable/disable the wake capabilities
517 * Argument 1: target system state
518 * Argument 2: target device state
519 * When _DSW object is called to disable the wake capabilities, maybe
520 * the first argument is filled. The values of the other two agruments
521 * are meaningless.
522 */
523 in_arg[0].type = ACPI_TYPE_INTEGER;
524 in_arg[0].integer.value = enable;
525 in_arg[1].type = ACPI_TYPE_INTEGER;
526 in_arg[1].integer.value = sleep_state;
527 in_arg[2].type = ACPI_TYPE_INTEGER;
528 in_arg[2].integer.value = dev_state;
529 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
530 if (ACPI_SUCCESS(status)) {
531 return 0;
532 } else if (status != AE_NOT_FOUND) {
533 printk(KERN_ERR PREFIX "_DSW execution failed\n");
534 dev->wakeup.flags.valid = 0;
535 return -ENODEV;
536 }
537
538 /* Execute _PSW */
539 status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
540 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
541 printk(KERN_ERR PREFIX "_PSW execution failed\n");
542 dev->wakeup.flags.valid = 0;
543 return -ENODEV;
544 }
545
546 return 0;
547}
548
549/*
550 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
551 * 1. Power on the power resources required for the wakeup device
552 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
553 * State Wake) for the device, if present
554 */
555int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
556{
557 struct acpi_power_resource_entry *entry;
558 int err = 0;
559
560 if (!dev || !dev->wakeup.flags.valid)
561 return -EINVAL;
562
563 mutex_lock(&acpi_device_lock);
564
565 if (dev->wakeup.prepare_count++)
566 goto out;
567
568 list_for_each_entry(entry, &dev->wakeup.resources, node) {
569 struct acpi_power_resource *resource = entry->resource;
570
571 mutex_lock(&resource->resource_lock);
572
573 if (!resource->wakeup_enabled) {
574 err = acpi_power_on_unlocked(resource);
575 if (!err)
576 resource->wakeup_enabled = true;
577 }
578
579 mutex_unlock(&resource->resource_lock);
580
581 if (err) {
582 dev_err(&dev->dev,
583 "Cannot turn wakeup power resources on\n");
584 dev->wakeup.flags.valid = 0;
585 goto out;
586 }
587 }
588 /*
589 * Passing 3 as the third argument below means the device may be
590 * put into arbitrary power state afterward.
591 */
592 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
593 if (err)
594 dev->wakeup.prepare_count = 0;
595
596 out:
597 mutex_unlock(&acpi_device_lock);
598 return err;
599}
600
601/*
602 * Shutdown a wakeup device, counterpart of above method
603 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
604 * State Wake) for the device, if present
605 * 2. Shutdown down the power resources
606 */
607int acpi_disable_wakeup_device_power(struct acpi_device *dev)
608{
609 struct acpi_power_resource_entry *entry;
610 int err = 0;
611
612 if (!dev || !dev->wakeup.flags.valid)
613 return -EINVAL;
614
615 mutex_lock(&acpi_device_lock);
616
617 if (--dev->wakeup.prepare_count > 0)
618 goto out;
619
620 /*
621 * Executing the code below even if prepare_count is already zero when
622 * the function is called may be useful, for example for initialisation.
623 */
624 if (dev->wakeup.prepare_count < 0)
625 dev->wakeup.prepare_count = 0;
626
627 err = acpi_device_sleep_wake(dev, 0, 0, 0);
628 if (err)
629 goto out;
630
631 list_for_each_entry(entry, &dev->wakeup.resources, node) {
632 struct acpi_power_resource *resource = entry->resource;
633
634 mutex_lock(&resource->resource_lock);
635
636 if (resource->wakeup_enabled) {
637 err = acpi_power_off_unlocked(resource);
638 if (!err)
639 resource->wakeup_enabled = false;
640 }
641
642 mutex_unlock(&resource->resource_lock);
643
644 if (err) {
645 dev_err(&dev->dev,
646 "Cannot turn wakeup power resources off\n");
647 dev->wakeup.flags.valid = 0;
648 break;
649 }
650 }
651
652 out:
653 mutex_unlock(&acpi_device_lock);
654 return err;
655}
656
657int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
658{
659 int result = 0;
660 int list_state = 0;
661 int i = 0;
662
663 if (!device || !state)
664 return -EINVAL;
665
666 /*
667 * We know a device's inferred power state when all the resources
668 * required for a given D-state are 'on'.
669 */
670 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
671 struct list_head *list = &device->power.states[i].resources;
672
673 if (list_empty(list))
674 continue;
675
676 result = acpi_power_get_list_state(list, &list_state);
677 if (result)
678 return result;
679
680 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
681 *state = i;
682 return 0;
683 }
684 }
685
686 *state = device->power.states[ACPI_STATE_D3_COLD].flags.valid ?
687 ACPI_STATE_D3_COLD : ACPI_STATE_D3_HOT;
688 return 0;
689}
690
691int acpi_power_on_resources(struct acpi_device *device, int state)
692{
693 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
694 return -EINVAL;
695
696 return acpi_power_on_list(&device->power.states[state].resources);
697}
698
699int acpi_power_transition(struct acpi_device *device, int state)
700{
701 int result = 0;
702
703 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
704 return -EINVAL;
705
706 if (device->power.state == state || !device->flags.power_manageable)
707 return 0;
708
709 if ((device->power.state < ACPI_STATE_D0)
710 || (device->power.state > ACPI_STATE_D3_COLD))
711 return -ENODEV;
712
713 /*
714 * First we reference all power resources required in the target list
715 * (e.g. so the device doesn't lose power while transitioning). Then,
716 * we dereference all power resources used in the current list.
717 */
718 if (state < ACPI_STATE_D3_COLD)
719 result = acpi_power_on_list(
720 &device->power.states[state].resources);
721
722 if (!result && device->power.state < ACPI_STATE_D3_COLD)
723 acpi_power_off_list(
724 &device->power.states[device->power.state].resources);
725
726 /* We shouldn't change the state unless the above operations succeed. */
727 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
728
729 return result;
730}
731
732static void acpi_release_power_resource(struct device *dev)
733{
734 struct acpi_device *device = to_acpi_device(dev);
735 struct acpi_power_resource *resource;
736
737 resource = container_of(device, struct acpi_power_resource, device);
738
739 mutex_lock(&power_resource_list_lock);
740 list_del(&resource->list_node);
741 mutex_unlock(&power_resource_list_lock);
742
743 acpi_free_pnp_ids(&device->pnp);
744 kfree(resource);
745}
746
747static ssize_t acpi_power_in_use_show(struct device *dev,
748 struct device_attribute *attr,
749 char *buf) {
750 struct acpi_power_resource *resource;
751
752 resource = to_power_resource(to_acpi_device(dev));
753 return sprintf(buf, "%u\n", !!resource->ref_count);
754}
755static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
756
757static void acpi_power_sysfs_remove(struct acpi_device *device)
758{
759 device_remove_file(&device->dev, &dev_attr_resource_in_use);
760}
761
762static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource)
763{
764 mutex_lock(&power_resource_list_lock);
765
766 if (!list_empty(&acpi_power_resource_list)) {
767 struct acpi_power_resource *r;
768
769 list_for_each_entry(r, &acpi_power_resource_list, list_node)
770 if (r->order > resource->order) {
771 list_add_tail(&resource->list_node, &r->list_node);
772 goto out;
773 }
774 }
775 list_add_tail(&resource->list_node, &acpi_power_resource_list);
776
777 out:
778 mutex_unlock(&power_resource_list_lock);
779}
780
781int acpi_add_power_resource(acpi_handle handle)
782{
783 struct acpi_power_resource *resource;
784 struct acpi_device *device = NULL;
785 union acpi_object acpi_object;
786 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
787 acpi_status status;
788 int state, result = -ENODEV;
789
790 acpi_bus_get_device(handle, &device);
791 if (device)
792 return 0;
793
794 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
795 if (!resource)
796 return -ENOMEM;
797
798 device = &resource->device;
799 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
800 ACPI_STA_DEFAULT);
801 mutex_init(&resource->resource_lock);
802 INIT_LIST_HEAD(&resource->list_node);
803 resource->name = device->pnp.bus_id;
804 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
805 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
806 device->power.state = ACPI_STATE_UNKNOWN;
807
808 /* Evalute the object to get the system level and resource order. */
809 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
810 if (ACPI_FAILURE(status))
811 goto err;
812
813 resource->system_level = acpi_object.power_resource.system_level;
814 resource->order = acpi_object.power_resource.resource_order;
815
816 result = acpi_power_get_state(handle, &state);
817 if (result)
818 goto err;
819
820 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
821 acpi_device_bid(device), state ? "on" : "off");
822
823 device->flags.match_driver = true;
824 result = acpi_device_add(device, acpi_release_power_resource);
825 if (result)
826 goto err;
827
828 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
829 device->remove = acpi_power_sysfs_remove;
830
831 acpi_power_add_resource_to_list(resource);
832 acpi_device_add_finalize(device);
833 return 0;
834
835 err:
836 acpi_release_power_resource(&device->dev);
837 return result;
838}
839
840#ifdef CONFIG_ACPI_SLEEP
841void acpi_resume_power_resources(void)
842{
843 struct acpi_power_resource *resource;
844
845 mutex_lock(&power_resource_list_lock);
846
847 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
848 int result, state;
849
850 mutex_lock(&resource->resource_lock);
851
852 result = acpi_power_get_state(resource->device.handle, &state);
853 if (result) {
854 mutex_unlock(&resource->resource_lock);
855 continue;
856 }
857
858 if (state == ACPI_POWER_RESOURCE_STATE_OFF
859 && resource->ref_count) {
860 dev_info(&resource->device.dev, "Turning ON\n");
861 __acpi_power_on(resource);
862 }
863
864 mutex_unlock(&resource->resource_lock);
865 }
866 list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
867 int result, state;
868
869 mutex_lock(&resource->resource_lock);
870
871 result = acpi_power_get_state(resource->device.handle, &state);
872 if (result) {
873 mutex_unlock(&resource->resource_lock);
874 continue;
875 }
876
877 if (state == ACPI_POWER_RESOURCE_STATE_ON
878 && !resource->ref_count) {
879 dev_info(&resource->device.dev, "Turning OFF\n");
880 __acpi_power_off(resource);
881 }
882
883 mutex_unlock(&resource->resource_lock);
884 }
885
886 mutex_unlock(&power_resource_list_lock);
887}
888#endif
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * drivers/acpi/power.c - ACPI Power Resources management.
4 *
5 * Copyright (C) 2001 - 2015 Intel Corp.
6 * Author: Andy Grover <andrew.grover@intel.com>
7 * Author: Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
8 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
9 */
10
11/*
12 * ACPI power-managed devices may be controlled in two ways:
13 * 1. via "Device Specific (D-State) Control"
14 * 2. via "Power Resource Control".
15 * The code below deals with ACPI Power Resources control.
16 *
17 * An ACPI "power resource object" represents a software controllable power
18 * plane, clock plane, or other resource depended on by a device.
19 *
20 * A device may rely on multiple power resources, and a power resource
21 * may be shared by multiple devices.
22 */
23
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/types.h>
28#include <linux/slab.h>
29#include <linux/pm_runtime.h>
30#include <linux/sysfs.h>
31#include <linux/acpi.h>
32#include "sleep.h"
33#include "internal.h"
34
35#define _COMPONENT ACPI_POWER_COMPONENT
36ACPI_MODULE_NAME("power");
37#define ACPI_POWER_CLASS "power_resource"
38#define ACPI_POWER_DEVICE_NAME "Power Resource"
39#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
40#define ACPI_POWER_RESOURCE_STATE_ON 0x01
41#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
42
43struct acpi_power_dependent_device {
44 struct device *dev;
45 struct list_head node;
46};
47
48struct acpi_power_resource {
49 struct acpi_device device;
50 struct list_head list_node;
51 char *name;
52 u32 system_level;
53 u32 order;
54 unsigned int ref_count;
55 bool wakeup_enabled;
56 struct mutex resource_lock;
57 struct list_head dependents;
58};
59
60struct acpi_power_resource_entry {
61 struct list_head node;
62 struct acpi_power_resource *resource;
63};
64
65static LIST_HEAD(acpi_power_resource_list);
66static DEFINE_MUTEX(power_resource_list_lock);
67
68/* --------------------------------------------------------------------------
69 Power Resource Management
70 -------------------------------------------------------------------------- */
71
72static inline
73struct acpi_power_resource *to_power_resource(struct acpi_device *device)
74{
75 return container_of(device, struct acpi_power_resource, device);
76}
77
78static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
79{
80 struct acpi_device *device;
81
82 if (acpi_bus_get_device(handle, &device))
83 return NULL;
84
85 return to_power_resource(device);
86}
87
88static int acpi_power_resources_list_add(acpi_handle handle,
89 struct list_head *list)
90{
91 struct acpi_power_resource *resource = acpi_power_get_context(handle);
92 struct acpi_power_resource_entry *entry;
93
94 if (!resource || !list)
95 return -EINVAL;
96
97 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
98 if (!entry)
99 return -ENOMEM;
100
101 entry->resource = resource;
102 if (!list_empty(list)) {
103 struct acpi_power_resource_entry *e;
104
105 list_for_each_entry(e, list, node)
106 if (e->resource->order > resource->order) {
107 list_add_tail(&entry->node, &e->node);
108 return 0;
109 }
110 }
111 list_add_tail(&entry->node, list);
112 return 0;
113}
114
115void acpi_power_resources_list_free(struct list_head *list)
116{
117 struct acpi_power_resource_entry *entry, *e;
118
119 list_for_each_entry_safe(entry, e, list, node) {
120 list_del(&entry->node);
121 kfree(entry);
122 }
123}
124
125static bool acpi_power_resource_is_dup(union acpi_object *package,
126 unsigned int start, unsigned int i)
127{
128 acpi_handle rhandle, dup;
129 unsigned int j;
130
131 /* The caller is expected to check the package element types */
132 rhandle = package->package.elements[i].reference.handle;
133 for (j = start; j < i; j++) {
134 dup = package->package.elements[j].reference.handle;
135 if (dup == rhandle)
136 return true;
137 }
138
139 return false;
140}
141
142int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
143 struct list_head *list)
144{
145 unsigned int i;
146 int err = 0;
147
148 for (i = start; i < package->package.count; i++) {
149 union acpi_object *element = &package->package.elements[i];
150 acpi_handle rhandle;
151
152 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
153 err = -ENODATA;
154 break;
155 }
156 rhandle = element->reference.handle;
157 if (!rhandle) {
158 err = -ENODEV;
159 break;
160 }
161
162 /* Some ACPI tables contain duplicate power resource references */
163 if (acpi_power_resource_is_dup(package, start, i))
164 continue;
165
166 err = acpi_add_power_resource(rhandle);
167 if (err)
168 break;
169
170 err = acpi_power_resources_list_add(rhandle, list);
171 if (err)
172 break;
173 }
174 if (err)
175 acpi_power_resources_list_free(list);
176
177 return err;
178}
179
180static int acpi_power_get_state(acpi_handle handle, int *state)
181{
182 acpi_status status = AE_OK;
183 unsigned long long sta = 0;
184 char node_name[5];
185 struct acpi_buffer buffer = { sizeof(node_name), node_name };
186
187
188 if (!handle || !state)
189 return -EINVAL;
190
191 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
192 if (ACPI_FAILURE(status))
193 return -ENODEV;
194
195 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
196 ACPI_POWER_RESOURCE_STATE_OFF;
197
198 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
199
200 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
201 node_name,
202 *state ? "on" : "off"));
203
204 return 0;
205}
206
207static int acpi_power_get_list_state(struct list_head *list, int *state)
208{
209 struct acpi_power_resource_entry *entry;
210 int cur_state;
211
212 if (!list || !state)
213 return -EINVAL;
214
215 /* The state of the list is 'on' IFF all resources are 'on'. */
216 cur_state = 0;
217 list_for_each_entry(entry, list, node) {
218 struct acpi_power_resource *resource = entry->resource;
219 acpi_handle handle = resource->device.handle;
220 int result;
221
222 mutex_lock(&resource->resource_lock);
223 result = acpi_power_get_state(handle, &cur_state);
224 mutex_unlock(&resource->resource_lock);
225 if (result)
226 return result;
227
228 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
229 break;
230 }
231
232 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
233 cur_state ? "on" : "off"));
234
235 *state = cur_state;
236 return 0;
237}
238
239static int
240acpi_power_resource_add_dependent(struct acpi_power_resource *resource,
241 struct device *dev)
242{
243 struct acpi_power_dependent_device *dep;
244 int ret = 0;
245
246 mutex_lock(&resource->resource_lock);
247 list_for_each_entry(dep, &resource->dependents, node) {
248 /* Only add it once */
249 if (dep->dev == dev)
250 goto unlock;
251 }
252
253 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
254 if (!dep) {
255 ret = -ENOMEM;
256 goto unlock;
257 }
258
259 dep->dev = dev;
260 list_add_tail(&dep->node, &resource->dependents);
261 dev_dbg(dev, "added power dependency to [%s]\n", resource->name);
262
263unlock:
264 mutex_unlock(&resource->resource_lock);
265 return ret;
266}
267
268static void
269acpi_power_resource_remove_dependent(struct acpi_power_resource *resource,
270 struct device *dev)
271{
272 struct acpi_power_dependent_device *dep;
273
274 mutex_lock(&resource->resource_lock);
275 list_for_each_entry(dep, &resource->dependents, node) {
276 if (dep->dev == dev) {
277 list_del(&dep->node);
278 kfree(dep);
279 dev_dbg(dev, "removed power dependency to [%s]\n",
280 resource->name);
281 break;
282 }
283 }
284 mutex_unlock(&resource->resource_lock);
285}
286
287/**
288 * acpi_device_power_add_dependent - Add dependent device of this ACPI device
289 * @adev: ACPI device pointer
290 * @dev: Dependent device
291 *
292 * If @adev has non-empty _PR0 the @dev is added as dependent device to all
293 * power resources returned by it. This means that whenever these power
294 * resources are turned _ON the dependent devices get runtime resumed. This
295 * is needed for devices such as PCI to allow its driver to re-initialize
296 * it after it went to D0uninitialized.
297 *
298 * If @adev does not have _PR0 this does nothing.
299 *
300 * Returns %0 in case of success and negative errno otherwise.
301 */
302int acpi_device_power_add_dependent(struct acpi_device *adev,
303 struct device *dev)
304{
305 struct acpi_power_resource_entry *entry;
306 struct list_head *resources;
307 int ret;
308
309 if (!adev->flags.power_manageable)
310 return 0;
311
312 resources = &adev->power.states[ACPI_STATE_D0].resources;
313 list_for_each_entry(entry, resources, node) {
314 ret = acpi_power_resource_add_dependent(entry->resource, dev);
315 if (ret)
316 goto err;
317 }
318
319 return 0;
320
321err:
322 list_for_each_entry(entry, resources, node)
323 acpi_power_resource_remove_dependent(entry->resource, dev);
324
325 return ret;
326}
327
328/**
329 * acpi_device_power_remove_dependent - Remove dependent device
330 * @adev: ACPI device pointer
331 * @dev: Dependent device
332 *
333 * Does the opposite of acpi_device_power_add_dependent() and removes the
334 * dependent device if it is found. Can be called to @adev that does not
335 * have _PR0 as well.
336 */
337void acpi_device_power_remove_dependent(struct acpi_device *adev,
338 struct device *dev)
339{
340 struct acpi_power_resource_entry *entry;
341 struct list_head *resources;
342
343 if (!adev->flags.power_manageable)
344 return;
345
346 resources = &adev->power.states[ACPI_STATE_D0].resources;
347 list_for_each_entry_reverse(entry, resources, node)
348 acpi_power_resource_remove_dependent(entry->resource, dev);
349}
350
351static int __acpi_power_on(struct acpi_power_resource *resource)
352{
353 struct acpi_power_dependent_device *dep;
354 acpi_status status = AE_OK;
355
356 status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL);
357 if (ACPI_FAILURE(status))
358 return -ENODEV;
359
360 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
361 resource->name));
362
363 /*
364 * If there are other dependents on this power resource we need to
365 * resume them now so that their drivers can re-initialize the
366 * hardware properly after it went back to D0.
367 */
368 if (list_empty(&resource->dependents) ||
369 list_is_singular(&resource->dependents))
370 return 0;
371
372 list_for_each_entry(dep, &resource->dependents, node) {
373 dev_dbg(dep->dev, "runtime resuming because [%s] turned on\n",
374 resource->name);
375 pm_request_resume(dep->dev);
376 }
377
378 return 0;
379}
380
381static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
382{
383 int result = 0;
384
385 if (resource->ref_count++) {
386 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
387 "Power resource [%s] already on\n",
388 resource->name));
389 } else {
390 result = __acpi_power_on(resource);
391 if (result)
392 resource->ref_count--;
393 }
394 return result;
395}
396
397static int acpi_power_on(struct acpi_power_resource *resource)
398{
399 int result;
400
401 mutex_lock(&resource->resource_lock);
402 result = acpi_power_on_unlocked(resource);
403 mutex_unlock(&resource->resource_lock);
404 return result;
405}
406
407static int __acpi_power_off(struct acpi_power_resource *resource)
408{
409 acpi_status status;
410
411 status = acpi_evaluate_object(resource->device.handle, "_OFF",
412 NULL, NULL);
413 if (ACPI_FAILURE(status))
414 return -ENODEV;
415
416 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned off\n",
417 resource->name));
418 return 0;
419}
420
421static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
422{
423 int result = 0;
424
425 if (!resource->ref_count) {
426 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
427 "Power resource [%s] already off\n",
428 resource->name));
429 return 0;
430 }
431
432 if (--resource->ref_count) {
433 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
434 "Power resource [%s] still in use\n",
435 resource->name));
436 } else {
437 result = __acpi_power_off(resource);
438 if (result)
439 resource->ref_count++;
440 }
441 return result;
442}
443
444static int acpi_power_off(struct acpi_power_resource *resource)
445{
446 int result;
447
448 mutex_lock(&resource->resource_lock);
449 result = acpi_power_off_unlocked(resource);
450 mutex_unlock(&resource->resource_lock);
451 return result;
452}
453
454static int acpi_power_off_list(struct list_head *list)
455{
456 struct acpi_power_resource_entry *entry;
457 int result = 0;
458
459 list_for_each_entry_reverse(entry, list, node) {
460 result = acpi_power_off(entry->resource);
461 if (result)
462 goto err;
463 }
464 return 0;
465
466 err:
467 list_for_each_entry_continue(entry, list, node)
468 acpi_power_on(entry->resource);
469
470 return result;
471}
472
473static int acpi_power_on_list(struct list_head *list)
474{
475 struct acpi_power_resource_entry *entry;
476 int result = 0;
477
478 list_for_each_entry(entry, list, node) {
479 result = acpi_power_on(entry->resource);
480 if (result)
481 goto err;
482 }
483 return 0;
484
485 err:
486 list_for_each_entry_continue_reverse(entry, list, node)
487 acpi_power_off(entry->resource);
488
489 return result;
490}
491
492static struct attribute *attrs[] = {
493 NULL,
494};
495
496static const struct attribute_group attr_groups[] = {
497 [ACPI_STATE_D0] = {
498 .name = "power_resources_D0",
499 .attrs = attrs,
500 },
501 [ACPI_STATE_D1] = {
502 .name = "power_resources_D1",
503 .attrs = attrs,
504 },
505 [ACPI_STATE_D2] = {
506 .name = "power_resources_D2",
507 .attrs = attrs,
508 },
509 [ACPI_STATE_D3_HOT] = {
510 .name = "power_resources_D3hot",
511 .attrs = attrs,
512 },
513};
514
515static const struct attribute_group wakeup_attr_group = {
516 .name = "power_resources_wakeup",
517 .attrs = attrs,
518};
519
520static void acpi_power_hide_list(struct acpi_device *adev,
521 struct list_head *resources,
522 const struct attribute_group *attr_group)
523{
524 struct acpi_power_resource_entry *entry;
525
526 if (list_empty(resources))
527 return;
528
529 list_for_each_entry_reverse(entry, resources, node) {
530 struct acpi_device *res_dev = &entry->resource->device;
531
532 sysfs_remove_link_from_group(&adev->dev.kobj,
533 attr_group->name,
534 dev_name(&res_dev->dev));
535 }
536 sysfs_remove_group(&adev->dev.kobj, attr_group);
537}
538
539static void acpi_power_expose_list(struct acpi_device *adev,
540 struct list_head *resources,
541 const struct attribute_group *attr_group)
542{
543 struct acpi_power_resource_entry *entry;
544 int ret;
545
546 if (list_empty(resources))
547 return;
548
549 ret = sysfs_create_group(&adev->dev.kobj, attr_group);
550 if (ret)
551 return;
552
553 list_for_each_entry(entry, resources, node) {
554 struct acpi_device *res_dev = &entry->resource->device;
555
556 ret = sysfs_add_link_to_group(&adev->dev.kobj,
557 attr_group->name,
558 &res_dev->dev.kobj,
559 dev_name(&res_dev->dev));
560 if (ret) {
561 acpi_power_hide_list(adev, resources, attr_group);
562 break;
563 }
564 }
565}
566
567static void acpi_power_expose_hide(struct acpi_device *adev,
568 struct list_head *resources,
569 const struct attribute_group *attr_group,
570 bool expose)
571{
572 if (expose)
573 acpi_power_expose_list(adev, resources, attr_group);
574 else
575 acpi_power_hide_list(adev, resources, attr_group);
576}
577
578void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
579{
580 int state;
581
582 if (adev->wakeup.flags.valid)
583 acpi_power_expose_hide(adev, &adev->wakeup.resources,
584 &wakeup_attr_group, add);
585
586 if (!adev->power.flags.power_resources)
587 return;
588
589 for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
590 acpi_power_expose_hide(adev,
591 &adev->power.states[state].resources,
592 &attr_groups[state], add);
593}
594
595int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
596{
597 struct acpi_power_resource_entry *entry;
598 int system_level = 5;
599
600 list_for_each_entry(entry, list, node) {
601 struct acpi_power_resource *resource = entry->resource;
602 acpi_handle handle = resource->device.handle;
603 int result;
604 int state;
605
606 mutex_lock(&resource->resource_lock);
607
608 result = acpi_power_get_state(handle, &state);
609 if (result) {
610 mutex_unlock(&resource->resource_lock);
611 return result;
612 }
613 if (state == ACPI_POWER_RESOURCE_STATE_ON) {
614 resource->ref_count++;
615 resource->wakeup_enabled = true;
616 }
617 if (system_level > resource->system_level)
618 system_level = resource->system_level;
619
620 mutex_unlock(&resource->resource_lock);
621 }
622 *system_level_p = system_level;
623 return 0;
624}
625
626/* --------------------------------------------------------------------------
627 Device Power Management
628 -------------------------------------------------------------------------- */
629
630/**
631 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
632 * ACPI 3.0) _PSW (Power State Wake)
633 * @dev: Device to handle.
634 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
635 * @sleep_state: Target sleep state of the system.
636 * @dev_state: Target power state of the device.
637 *
638 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
639 * State Wake) for the device, if present. On failure reset the device's
640 * wakeup.flags.valid flag.
641 *
642 * RETURN VALUE:
643 * 0 if either _DSW or _PSW has been successfully executed
644 * 0 if neither _DSW nor _PSW has been found
645 * -ENODEV if the execution of either _DSW or _PSW has failed
646 */
647int acpi_device_sleep_wake(struct acpi_device *dev,
648 int enable, int sleep_state, int dev_state)
649{
650 union acpi_object in_arg[3];
651 struct acpi_object_list arg_list = { 3, in_arg };
652 acpi_status status = AE_OK;
653
654 /*
655 * Try to execute _DSW first.
656 *
657 * Three arguments are needed for the _DSW object:
658 * Argument 0: enable/disable the wake capabilities
659 * Argument 1: target system state
660 * Argument 2: target device state
661 * When _DSW object is called to disable the wake capabilities, maybe
662 * the first argument is filled. The values of the other two arguments
663 * are meaningless.
664 */
665 in_arg[0].type = ACPI_TYPE_INTEGER;
666 in_arg[0].integer.value = enable;
667 in_arg[1].type = ACPI_TYPE_INTEGER;
668 in_arg[1].integer.value = sleep_state;
669 in_arg[2].type = ACPI_TYPE_INTEGER;
670 in_arg[2].integer.value = dev_state;
671 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
672 if (ACPI_SUCCESS(status)) {
673 return 0;
674 } else if (status != AE_NOT_FOUND) {
675 printk(KERN_ERR PREFIX "_DSW execution failed\n");
676 dev->wakeup.flags.valid = 0;
677 return -ENODEV;
678 }
679
680 /* Execute _PSW */
681 status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
682 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
683 printk(KERN_ERR PREFIX "_PSW execution failed\n");
684 dev->wakeup.flags.valid = 0;
685 return -ENODEV;
686 }
687
688 return 0;
689}
690
691/*
692 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
693 * 1. Power on the power resources required for the wakeup device
694 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
695 * State Wake) for the device, if present
696 */
697int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
698{
699 struct acpi_power_resource_entry *entry;
700 int err = 0;
701
702 if (!dev || !dev->wakeup.flags.valid)
703 return -EINVAL;
704
705 mutex_lock(&acpi_device_lock);
706
707 if (dev->wakeup.prepare_count++)
708 goto out;
709
710 list_for_each_entry(entry, &dev->wakeup.resources, node) {
711 struct acpi_power_resource *resource = entry->resource;
712
713 mutex_lock(&resource->resource_lock);
714
715 if (!resource->wakeup_enabled) {
716 err = acpi_power_on_unlocked(resource);
717 if (!err)
718 resource->wakeup_enabled = true;
719 }
720
721 mutex_unlock(&resource->resource_lock);
722
723 if (err) {
724 dev_err(&dev->dev,
725 "Cannot turn wakeup power resources on\n");
726 dev->wakeup.flags.valid = 0;
727 goto out;
728 }
729 }
730 /*
731 * Passing 3 as the third argument below means the device may be
732 * put into arbitrary power state afterward.
733 */
734 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
735 if (err)
736 dev->wakeup.prepare_count = 0;
737
738 out:
739 mutex_unlock(&acpi_device_lock);
740 return err;
741}
742
743/*
744 * Shutdown a wakeup device, counterpart of above method
745 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
746 * State Wake) for the device, if present
747 * 2. Shutdown down the power resources
748 */
749int acpi_disable_wakeup_device_power(struct acpi_device *dev)
750{
751 struct acpi_power_resource_entry *entry;
752 int err = 0;
753
754 if (!dev || !dev->wakeup.flags.valid)
755 return -EINVAL;
756
757 mutex_lock(&acpi_device_lock);
758
759 if (--dev->wakeup.prepare_count > 0)
760 goto out;
761
762 /*
763 * Executing the code below even if prepare_count is already zero when
764 * the function is called may be useful, for example for initialisation.
765 */
766 if (dev->wakeup.prepare_count < 0)
767 dev->wakeup.prepare_count = 0;
768
769 err = acpi_device_sleep_wake(dev, 0, 0, 0);
770 if (err)
771 goto out;
772
773 list_for_each_entry(entry, &dev->wakeup.resources, node) {
774 struct acpi_power_resource *resource = entry->resource;
775
776 mutex_lock(&resource->resource_lock);
777
778 if (resource->wakeup_enabled) {
779 err = acpi_power_off_unlocked(resource);
780 if (!err)
781 resource->wakeup_enabled = false;
782 }
783
784 mutex_unlock(&resource->resource_lock);
785
786 if (err) {
787 dev_err(&dev->dev,
788 "Cannot turn wakeup power resources off\n");
789 dev->wakeup.flags.valid = 0;
790 break;
791 }
792 }
793
794 out:
795 mutex_unlock(&acpi_device_lock);
796 return err;
797}
798
799int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
800{
801 int result = 0;
802 int list_state = 0;
803 int i = 0;
804
805 if (!device || !state)
806 return -EINVAL;
807
808 /*
809 * We know a device's inferred power state when all the resources
810 * required for a given D-state are 'on'.
811 */
812 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
813 struct list_head *list = &device->power.states[i].resources;
814
815 if (list_empty(list))
816 continue;
817
818 result = acpi_power_get_list_state(list, &list_state);
819 if (result)
820 return result;
821
822 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
823 *state = i;
824 return 0;
825 }
826 }
827
828 *state = device->power.states[ACPI_STATE_D3_COLD].flags.valid ?
829 ACPI_STATE_D3_COLD : ACPI_STATE_D3_HOT;
830 return 0;
831}
832
833int acpi_power_on_resources(struct acpi_device *device, int state)
834{
835 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
836 return -EINVAL;
837
838 return acpi_power_on_list(&device->power.states[state].resources);
839}
840
841int acpi_power_transition(struct acpi_device *device, int state)
842{
843 int result = 0;
844
845 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
846 return -EINVAL;
847
848 if (device->power.state == state || !device->flags.power_manageable)
849 return 0;
850
851 if ((device->power.state < ACPI_STATE_D0)
852 || (device->power.state > ACPI_STATE_D3_COLD))
853 return -ENODEV;
854
855 /*
856 * First we reference all power resources required in the target list
857 * (e.g. so the device doesn't lose power while transitioning). Then,
858 * we dereference all power resources used in the current list.
859 */
860 if (state < ACPI_STATE_D3_COLD)
861 result = acpi_power_on_list(
862 &device->power.states[state].resources);
863
864 if (!result && device->power.state < ACPI_STATE_D3_COLD)
865 acpi_power_off_list(
866 &device->power.states[device->power.state].resources);
867
868 /* We shouldn't change the state unless the above operations succeed. */
869 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
870
871 return result;
872}
873
874static void acpi_release_power_resource(struct device *dev)
875{
876 struct acpi_device *device = to_acpi_device(dev);
877 struct acpi_power_resource *resource;
878
879 resource = container_of(device, struct acpi_power_resource, device);
880
881 mutex_lock(&power_resource_list_lock);
882 list_del(&resource->list_node);
883 mutex_unlock(&power_resource_list_lock);
884
885 acpi_free_pnp_ids(&device->pnp);
886 kfree(resource);
887}
888
889static ssize_t acpi_power_in_use_show(struct device *dev,
890 struct device_attribute *attr,
891 char *buf) {
892 struct acpi_power_resource *resource;
893
894 resource = to_power_resource(to_acpi_device(dev));
895 return sprintf(buf, "%u\n", !!resource->ref_count);
896}
897static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
898
899static void acpi_power_sysfs_remove(struct acpi_device *device)
900{
901 device_remove_file(&device->dev, &dev_attr_resource_in_use);
902}
903
904static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource)
905{
906 mutex_lock(&power_resource_list_lock);
907
908 if (!list_empty(&acpi_power_resource_list)) {
909 struct acpi_power_resource *r;
910
911 list_for_each_entry(r, &acpi_power_resource_list, list_node)
912 if (r->order > resource->order) {
913 list_add_tail(&resource->list_node, &r->list_node);
914 goto out;
915 }
916 }
917 list_add_tail(&resource->list_node, &acpi_power_resource_list);
918
919 out:
920 mutex_unlock(&power_resource_list_lock);
921}
922
923int acpi_add_power_resource(acpi_handle handle)
924{
925 struct acpi_power_resource *resource;
926 struct acpi_device *device = NULL;
927 union acpi_object acpi_object;
928 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
929 acpi_status status;
930 int state, result = -ENODEV;
931
932 acpi_bus_get_device(handle, &device);
933 if (device)
934 return 0;
935
936 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
937 if (!resource)
938 return -ENOMEM;
939
940 device = &resource->device;
941 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
942 ACPI_STA_DEFAULT);
943 mutex_init(&resource->resource_lock);
944 INIT_LIST_HEAD(&resource->list_node);
945 INIT_LIST_HEAD(&resource->dependents);
946 resource->name = device->pnp.bus_id;
947 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
948 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
949 device->power.state = ACPI_STATE_UNKNOWN;
950
951 /* Evalute the object to get the system level and resource order. */
952 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
953 if (ACPI_FAILURE(status))
954 goto err;
955
956 resource->system_level = acpi_object.power_resource.system_level;
957 resource->order = acpi_object.power_resource.resource_order;
958
959 result = acpi_power_get_state(handle, &state);
960 if (result)
961 goto err;
962
963 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
964 acpi_device_bid(device), state ? "on" : "off");
965
966 device->flags.match_driver = true;
967 result = acpi_device_add(device, acpi_release_power_resource);
968 if (result)
969 goto err;
970
971 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
972 device->remove = acpi_power_sysfs_remove;
973
974 acpi_power_add_resource_to_list(resource);
975 acpi_device_add_finalize(device);
976 return 0;
977
978 err:
979 acpi_release_power_resource(&device->dev);
980 return result;
981}
982
983#ifdef CONFIG_ACPI_SLEEP
984void acpi_resume_power_resources(void)
985{
986 struct acpi_power_resource *resource;
987
988 mutex_lock(&power_resource_list_lock);
989
990 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
991 int result, state;
992
993 mutex_lock(&resource->resource_lock);
994
995 result = acpi_power_get_state(resource->device.handle, &state);
996 if (result) {
997 mutex_unlock(&resource->resource_lock);
998 continue;
999 }
1000
1001 if (state == ACPI_POWER_RESOURCE_STATE_OFF
1002 && resource->ref_count) {
1003 dev_info(&resource->device.dev, "Turning ON\n");
1004 __acpi_power_on(resource);
1005 }
1006
1007 mutex_unlock(&resource->resource_lock);
1008 }
1009
1010 mutex_unlock(&power_resource_list_lock);
1011}
1012
1013void acpi_turn_off_unused_power_resources(void)
1014{
1015 struct acpi_power_resource *resource;
1016
1017 mutex_lock(&power_resource_list_lock);
1018
1019 list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
1020 int result, state;
1021
1022 mutex_lock(&resource->resource_lock);
1023
1024 result = acpi_power_get_state(resource->device.handle, &state);
1025 if (result) {
1026 mutex_unlock(&resource->resource_lock);
1027 continue;
1028 }
1029
1030 if (state == ACPI_POWER_RESOURCE_STATE_ON
1031 && !resource->ref_count) {
1032 dev_info(&resource->device.dev, "Turning OFF\n");
1033 __acpi_power_off(resource);
1034 }
1035
1036 mutex_unlock(&resource->resource_lock);
1037 }
1038
1039 mutex_unlock(&power_resource_list_lock);
1040}
1041#endif