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