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
134static bool acpi_power_resource_is_dup(union acpi_object *package,
135 unsigned int start, unsigned int i)
136{
137 acpi_handle rhandle, dup;
138 unsigned int j;
139
140 /* The caller is expected to check the package element types */
141 rhandle = package->package.elements[i].reference.handle;
142 for (j = start; j < i; j++) {
143 dup = package->package.elements[j].reference.handle;
144 if (dup == rhandle)
145 return true;
146 }
147
148 return false;
149}
150
151int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
152 struct list_head *list)
153{
154 unsigned int i;
155 int err = 0;
156
157 for (i = start; i < package->package.count; i++) {
158 union acpi_object *element = &package->package.elements[i];
159 acpi_handle rhandle;
160
161 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
162 err = -ENODATA;
163 break;
164 }
165 rhandle = element->reference.handle;
166 if (!rhandle) {
167 err = -ENODEV;
168 break;
169 }
170
171 /* Some ACPI tables contain duplicate power resource references */
172 if (acpi_power_resource_is_dup(package, start, i))
173 continue;
174
175 err = acpi_add_power_resource(rhandle);
176 if (err)
177 break;
178
179 err = acpi_power_resources_list_add(rhandle, list);
180 if (err)
181 break;
182 }
183 if (err)
184 acpi_power_resources_list_free(list);
185
186 return err;
187}
188
189static int acpi_power_get_state(acpi_handle handle, int *state)
190{
191 acpi_status status = AE_OK;
192 unsigned long long sta = 0;
193 char node_name[5];
194 struct acpi_buffer buffer = { sizeof(node_name), node_name };
195
196
197 if (!handle || !state)
198 return -EINVAL;
199
200 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
201 if (ACPI_FAILURE(status))
202 return -ENODEV;
203
204 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
205 ACPI_POWER_RESOURCE_STATE_OFF;
206
207 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
208
209 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
210 node_name,
211 *state ? "on" : "off"));
212
213 return 0;
214}
215
216static int acpi_power_get_list_state(struct list_head *list, int *state)
217{
218 struct acpi_power_resource_entry *entry;
219 int cur_state;
220
221 if (!list || !state)
222 return -EINVAL;
223
224 /* The state of the list is 'on' IFF all resources are 'on'. */
225 cur_state = 0;
226 list_for_each_entry(entry, list, node) {
227 struct acpi_power_resource *resource = entry->resource;
228 acpi_handle handle = resource->device.handle;
229 int result;
230
231 mutex_lock(&resource->resource_lock);
232 result = acpi_power_get_state(handle, &cur_state);
233 mutex_unlock(&resource->resource_lock);
234 if (result)
235 return result;
236
237 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
238 break;
239 }
240
241 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
242 cur_state ? "on" : "off"));
243
244 *state = cur_state;
245 return 0;
246}
247
248static int __acpi_power_on(struct acpi_power_resource *resource)
249{
250 acpi_status status = AE_OK;
251
252 status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL);
253 if (ACPI_FAILURE(status))
254 return -ENODEV;
255
256 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
257 resource->name));
258
259 return 0;
260}
261
262static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
263{
264 int result = 0;
265
266 if (resource->ref_count++) {
267 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
268 "Power resource [%s] already on\n",
269 resource->name));
270 } else {
271 result = __acpi_power_on(resource);
272 if (result)
273 resource->ref_count--;
274 }
275 return result;
276}
277
278static int acpi_power_on(struct acpi_power_resource *resource)
279{
280 int result;
281
282 mutex_lock(&resource->resource_lock);
283 result = acpi_power_on_unlocked(resource);
284 mutex_unlock(&resource->resource_lock);
285 return result;
286}
287
288static int __acpi_power_off(struct acpi_power_resource *resource)
289{
290 acpi_status status;
291
292 status = acpi_evaluate_object(resource->device.handle, "_OFF",
293 NULL, NULL);
294 if (ACPI_FAILURE(status))
295 return -ENODEV;
296
297 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned off\n",
298 resource->name));
299 return 0;
300}
301
302static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
303{
304 int result = 0;
305
306 if (!resource->ref_count) {
307 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
308 "Power resource [%s] already off\n",
309 resource->name));
310 return 0;
311 }
312
313 if (--resource->ref_count) {
314 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
315 "Power resource [%s] still in use\n",
316 resource->name));
317 } else {
318 result = __acpi_power_off(resource);
319 if (result)
320 resource->ref_count++;
321 }
322 return result;
323}
324
325static int acpi_power_off(struct acpi_power_resource *resource)
326{
327 int result;
328
329 mutex_lock(&resource->resource_lock);
330 result = acpi_power_off_unlocked(resource);
331 mutex_unlock(&resource->resource_lock);
332 return result;
333}
334
335static int acpi_power_off_list(struct list_head *list)
336{
337 struct acpi_power_resource_entry *entry;
338 int result = 0;
339
340 list_for_each_entry_reverse(entry, list, node) {
341 result = acpi_power_off(entry->resource);
342 if (result)
343 goto err;
344 }
345 return 0;
346
347 err:
348 list_for_each_entry_continue(entry, list, node)
349 acpi_power_on(entry->resource);
350
351 return result;
352}
353
354static int acpi_power_on_list(struct list_head *list)
355{
356 struct acpi_power_resource_entry *entry;
357 int result = 0;
358
359 list_for_each_entry(entry, list, node) {
360 result = acpi_power_on(entry->resource);
361 if (result)
362 goto err;
363 }
364 return 0;
365
366 err:
367 list_for_each_entry_continue_reverse(entry, list, node)
368 acpi_power_off(entry->resource);
369
370 return result;
371}
372
373static struct attribute *attrs[] = {
374 NULL,
375};
376
377static const struct attribute_group attr_groups[] = {
378 [ACPI_STATE_D0] = {
379 .name = "power_resources_D0",
380 .attrs = attrs,
381 },
382 [ACPI_STATE_D1] = {
383 .name = "power_resources_D1",
384 .attrs = attrs,
385 },
386 [ACPI_STATE_D2] = {
387 .name = "power_resources_D2",
388 .attrs = attrs,
389 },
390 [ACPI_STATE_D3_HOT] = {
391 .name = "power_resources_D3hot",
392 .attrs = attrs,
393 },
394};
395
396static const struct attribute_group wakeup_attr_group = {
397 .name = "power_resources_wakeup",
398 .attrs = attrs,
399};
400
401static void acpi_power_hide_list(struct acpi_device *adev,
402 struct list_head *resources,
403 const struct attribute_group *attr_group)
404{
405 struct acpi_power_resource_entry *entry;
406
407 if (list_empty(resources))
408 return;
409
410 list_for_each_entry_reverse(entry, resources, node) {
411 struct acpi_device *res_dev = &entry->resource->device;
412
413 sysfs_remove_link_from_group(&adev->dev.kobj,
414 attr_group->name,
415 dev_name(&res_dev->dev));
416 }
417 sysfs_remove_group(&adev->dev.kobj, attr_group);
418}
419
420static void acpi_power_expose_list(struct acpi_device *adev,
421 struct list_head *resources,
422 const struct attribute_group *attr_group)
423{
424 struct acpi_power_resource_entry *entry;
425 int ret;
426
427 if (list_empty(resources))
428 return;
429
430 ret = sysfs_create_group(&adev->dev.kobj, attr_group);
431 if (ret)
432 return;
433
434 list_for_each_entry(entry, resources, node) {
435 struct acpi_device *res_dev = &entry->resource->device;
436
437 ret = sysfs_add_link_to_group(&adev->dev.kobj,
438 attr_group->name,
439 &res_dev->dev.kobj,
440 dev_name(&res_dev->dev));
441 if (ret) {
442 acpi_power_hide_list(adev, resources, attr_group);
443 break;
444 }
445 }
446}
447
448static void acpi_power_expose_hide(struct acpi_device *adev,
449 struct list_head *resources,
450 const struct attribute_group *attr_group,
451 bool expose)
452{
453 if (expose)
454 acpi_power_expose_list(adev, resources, attr_group);
455 else
456 acpi_power_hide_list(adev, resources, attr_group);
457}
458
459void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
460{
461 int state;
462
463 if (adev->wakeup.flags.valid)
464 acpi_power_expose_hide(adev, &adev->wakeup.resources,
465 &wakeup_attr_group, add);
466
467 if (!adev->power.flags.power_resources)
468 return;
469
470 for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
471 acpi_power_expose_hide(adev,
472 &adev->power.states[state].resources,
473 &attr_groups[state], add);
474}
475
476int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
477{
478 struct acpi_power_resource_entry *entry;
479 int system_level = 5;
480
481 list_for_each_entry(entry, list, node) {
482 struct acpi_power_resource *resource = entry->resource;
483 acpi_handle handle = resource->device.handle;
484 int result;
485 int state;
486
487 mutex_lock(&resource->resource_lock);
488
489 result = acpi_power_get_state(handle, &state);
490 if (result) {
491 mutex_unlock(&resource->resource_lock);
492 return result;
493 }
494 if (state == ACPI_POWER_RESOURCE_STATE_ON) {
495 resource->ref_count++;
496 resource->wakeup_enabled = true;
497 }
498 if (system_level > resource->system_level)
499 system_level = resource->system_level;
500
501 mutex_unlock(&resource->resource_lock);
502 }
503 *system_level_p = system_level;
504 return 0;
505}
506
507/* --------------------------------------------------------------------------
508 Device Power Management
509 -------------------------------------------------------------------------- */
510
511/**
512 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
513 * ACPI 3.0) _PSW (Power State Wake)
514 * @dev: Device to handle.
515 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
516 * @sleep_state: Target sleep state of the system.
517 * @dev_state: Target power state of the device.
518 *
519 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
520 * State Wake) for the device, if present. On failure reset the device's
521 * wakeup.flags.valid flag.
522 *
523 * RETURN VALUE:
524 * 0 if either _DSW or _PSW has been successfully executed
525 * 0 if neither _DSW nor _PSW has been found
526 * -ENODEV if the execution of either _DSW or _PSW has failed
527 */
528int acpi_device_sleep_wake(struct acpi_device *dev,
529 int enable, int sleep_state, int dev_state)
530{
531 union acpi_object in_arg[3];
532 struct acpi_object_list arg_list = { 3, in_arg };
533 acpi_status status = AE_OK;
534
535 /*
536 * Try to execute _DSW first.
537 *
538 * Three agruments are needed for the _DSW object:
539 * Argument 0: enable/disable the wake capabilities
540 * Argument 1: target system state
541 * Argument 2: target device state
542 * When _DSW object is called to disable the wake capabilities, maybe
543 * the first argument is filled. The values of the other two agruments
544 * are meaningless.
545 */
546 in_arg[0].type = ACPI_TYPE_INTEGER;
547 in_arg[0].integer.value = enable;
548 in_arg[1].type = ACPI_TYPE_INTEGER;
549 in_arg[1].integer.value = sleep_state;
550 in_arg[2].type = ACPI_TYPE_INTEGER;
551 in_arg[2].integer.value = dev_state;
552 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
553 if (ACPI_SUCCESS(status)) {
554 return 0;
555 } else if (status != AE_NOT_FOUND) {
556 printk(KERN_ERR PREFIX "_DSW execution failed\n");
557 dev->wakeup.flags.valid = 0;
558 return -ENODEV;
559 }
560
561 /* Execute _PSW */
562 status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
563 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
564 printk(KERN_ERR PREFIX "_PSW execution failed\n");
565 dev->wakeup.flags.valid = 0;
566 return -ENODEV;
567 }
568
569 return 0;
570}
571
572/*
573 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
574 * 1. Power on the power resources required for the wakeup device
575 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
576 * State Wake) for the device, if present
577 */
578int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
579{
580 struct acpi_power_resource_entry *entry;
581 int err = 0;
582
583 if (!dev || !dev->wakeup.flags.valid)
584 return -EINVAL;
585
586 mutex_lock(&acpi_device_lock);
587
588 if (dev->wakeup.prepare_count++)
589 goto out;
590
591 list_for_each_entry(entry, &dev->wakeup.resources, node) {
592 struct acpi_power_resource *resource = entry->resource;
593
594 mutex_lock(&resource->resource_lock);
595
596 if (!resource->wakeup_enabled) {
597 err = acpi_power_on_unlocked(resource);
598 if (!err)
599 resource->wakeup_enabled = true;
600 }
601
602 mutex_unlock(&resource->resource_lock);
603
604 if (err) {
605 dev_err(&dev->dev,
606 "Cannot turn wakeup power resources on\n");
607 dev->wakeup.flags.valid = 0;
608 goto out;
609 }
610 }
611 /*
612 * Passing 3 as the third argument below means the device may be
613 * put into arbitrary power state afterward.
614 */
615 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
616 if (err)
617 dev->wakeup.prepare_count = 0;
618
619 out:
620 mutex_unlock(&acpi_device_lock);
621 return err;
622}
623
624/*
625 * Shutdown a wakeup device, counterpart of above method
626 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
627 * State Wake) for the device, if present
628 * 2. Shutdown down the power resources
629 */
630int acpi_disable_wakeup_device_power(struct acpi_device *dev)
631{
632 struct acpi_power_resource_entry *entry;
633 int err = 0;
634
635 if (!dev || !dev->wakeup.flags.valid)
636 return -EINVAL;
637
638 mutex_lock(&acpi_device_lock);
639
640 if (--dev->wakeup.prepare_count > 0)
641 goto out;
642
643 /*
644 * Executing the code below even if prepare_count is already zero when
645 * the function is called may be useful, for example for initialisation.
646 */
647 if (dev->wakeup.prepare_count < 0)
648 dev->wakeup.prepare_count = 0;
649
650 err = acpi_device_sleep_wake(dev, 0, 0, 0);
651 if (err)
652 goto out;
653
654 list_for_each_entry(entry, &dev->wakeup.resources, node) {
655 struct acpi_power_resource *resource = entry->resource;
656
657 mutex_lock(&resource->resource_lock);
658
659 if (resource->wakeup_enabled) {
660 err = acpi_power_off_unlocked(resource);
661 if (!err)
662 resource->wakeup_enabled = false;
663 }
664
665 mutex_unlock(&resource->resource_lock);
666
667 if (err) {
668 dev_err(&dev->dev,
669 "Cannot turn wakeup power resources off\n");
670 dev->wakeup.flags.valid = 0;
671 break;
672 }
673 }
674
675 out:
676 mutex_unlock(&acpi_device_lock);
677 return err;
678}
679
680int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
681{
682 int result = 0;
683 int list_state = 0;
684 int i = 0;
685
686 if (!device || !state)
687 return -EINVAL;
688
689 /*
690 * We know a device's inferred power state when all the resources
691 * required for a given D-state are 'on'.
692 */
693 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
694 struct list_head *list = &device->power.states[i].resources;
695
696 if (list_empty(list))
697 continue;
698
699 result = acpi_power_get_list_state(list, &list_state);
700 if (result)
701 return result;
702
703 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
704 *state = i;
705 return 0;
706 }
707 }
708
709 *state = device->power.states[ACPI_STATE_D3_COLD].flags.valid ?
710 ACPI_STATE_D3_COLD : ACPI_STATE_D3_HOT;
711 return 0;
712}
713
714int acpi_power_on_resources(struct acpi_device *device, int state)
715{
716 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
717 return -EINVAL;
718
719 return acpi_power_on_list(&device->power.states[state].resources);
720}
721
722int acpi_power_transition(struct acpi_device *device, int state)
723{
724 int result = 0;
725
726 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
727 return -EINVAL;
728
729 if (device->power.state == state || !device->flags.power_manageable)
730 return 0;
731
732 if ((device->power.state < ACPI_STATE_D0)
733 || (device->power.state > ACPI_STATE_D3_COLD))
734 return -ENODEV;
735
736 /*
737 * First we reference all power resources required in the target list
738 * (e.g. so the device doesn't lose power while transitioning). Then,
739 * we dereference all power resources used in the current list.
740 */
741 if (state < ACPI_STATE_D3_COLD)
742 result = acpi_power_on_list(
743 &device->power.states[state].resources);
744
745 if (!result && device->power.state < ACPI_STATE_D3_COLD)
746 acpi_power_off_list(
747 &device->power.states[device->power.state].resources);
748
749 /* We shouldn't change the state unless the above operations succeed. */
750 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
751
752 return result;
753}
754
755static void acpi_release_power_resource(struct device *dev)
756{
757 struct acpi_device *device = to_acpi_device(dev);
758 struct acpi_power_resource *resource;
759
760 resource = container_of(device, struct acpi_power_resource, device);
761
762 mutex_lock(&power_resource_list_lock);
763 list_del(&resource->list_node);
764 mutex_unlock(&power_resource_list_lock);
765
766 acpi_free_pnp_ids(&device->pnp);
767 kfree(resource);
768}
769
770static ssize_t acpi_power_in_use_show(struct device *dev,
771 struct device_attribute *attr,
772 char *buf) {
773 struct acpi_power_resource *resource;
774
775 resource = to_power_resource(to_acpi_device(dev));
776 return sprintf(buf, "%u\n", !!resource->ref_count);
777}
778static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
779
780static void acpi_power_sysfs_remove(struct acpi_device *device)
781{
782 device_remove_file(&device->dev, &dev_attr_resource_in_use);
783}
784
785static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource)
786{
787 mutex_lock(&power_resource_list_lock);
788
789 if (!list_empty(&acpi_power_resource_list)) {
790 struct acpi_power_resource *r;
791
792 list_for_each_entry(r, &acpi_power_resource_list, list_node)
793 if (r->order > resource->order) {
794 list_add_tail(&resource->list_node, &r->list_node);
795 goto out;
796 }
797 }
798 list_add_tail(&resource->list_node, &acpi_power_resource_list);
799
800 out:
801 mutex_unlock(&power_resource_list_lock);
802}
803
804int acpi_add_power_resource(acpi_handle handle)
805{
806 struct acpi_power_resource *resource;
807 struct acpi_device *device = NULL;
808 union acpi_object acpi_object;
809 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
810 acpi_status status;
811 int state, result = -ENODEV;
812
813 acpi_bus_get_device(handle, &device);
814 if (device)
815 return 0;
816
817 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
818 if (!resource)
819 return -ENOMEM;
820
821 device = &resource->device;
822 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
823 ACPI_STA_DEFAULT);
824 mutex_init(&resource->resource_lock);
825 INIT_LIST_HEAD(&resource->list_node);
826 resource->name = device->pnp.bus_id;
827 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
828 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
829 device->power.state = ACPI_STATE_UNKNOWN;
830
831 /* Evalute the object to get the system level and resource order. */
832 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
833 if (ACPI_FAILURE(status))
834 goto err;
835
836 resource->system_level = acpi_object.power_resource.system_level;
837 resource->order = acpi_object.power_resource.resource_order;
838
839 result = acpi_power_get_state(handle, &state);
840 if (result)
841 goto err;
842
843 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
844 acpi_device_bid(device), state ? "on" : "off");
845
846 device->flags.match_driver = true;
847 result = acpi_device_add(device, acpi_release_power_resource);
848 if (result)
849 goto err;
850
851 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
852 device->remove = acpi_power_sysfs_remove;
853
854 acpi_power_add_resource_to_list(resource);
855 acpi_device_add_finalize(device);
856 return 0;
857
858 err:
859 acpi_release_power_resource(&device->dev);
860 return result;
861}
862
863#ifdef CONFIG_ACPI_SLEEP
864void acpi_resume_power_resources(void)
865{
866 struct acpi_power_resource *resource;
867
868 mutex_lock(&power_resource_list_lock);
869
870 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
871 int result, state;
872
873 mutex_lock(&resource->resource_lock);
874
875 result = acpi_power_get_state(resource->device.handle, &state);
876 if (result) {
877 mutex_unlock(&resource->resource_lock);
878 continue;
879 }
880
881 if (state == ACPI_POWER_RESOURCE_STATE_OFF
882 && resource->ref_count) {
883 dev_info(&resource->device.dev, "Turning ON\n");
884 __acpi_power_on(resource);
885 }
886
887 mutex_unlock(&resource->resource_lock);
888 }
889
890 mutex_unlock(&power_resource_list_lock);
891}
892
893void acpi_turn_off_unused_power_resources(void)
894{
895 struct acpi_power_resource *resource;
896
897 mutex_lock(&power_resource_list_lock);
898
899 list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
900 int result, state;
901
902 mutex_lock(&resource->resource_lock);
903
904 result = acpi_power_get_state(resource->device.handle, &state);
905 if (result) {
906 mutex_unlock(&resource->resource_lock);
907 continue;
908 }
909
910 if (state == ACPI_POWER_RESOURCE_STATE_ON
911 && !resource->ref_count) {
912 dev_info(&resource->device.dev, "Turning OFF\n");
913 __acpi_power_off(resource);
914 }
915
916 mutex_unlock(&resource->resource_lock);
917 }
918
919 mutex_unlock(&power_resource_list_lock);
920}
921#endif
922