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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#define pr_fmt(fmt) "ACPI: PM: " fmt
25
26#include <linux/dmi.h>
27#include <linux/kernel.h>
28#include <linux/module.h>
29#include <linux/init.h>
30#include <linux/types.h>
31#include <linux/slab.h>
32#include <linux/pm_runtime.h>
33#include <linux/sysfs.h>
34#include <linux/acpi.h>
35#include "sleep.h"
36#include "internal.h"
37
38#define ACPI_POWER_CLASS "power_resource"
39#define ACPI_POWER_DEVICE_NAME "Power Resource"
40#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
41#define ACPI_POWER_RESOURCE_STATE_ON 0x01
42#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
43
44struct acpi_power_dependent_device {
45 struct device *dev;
46 struct list_head node;
47};
48
49struct acpi_power_resource {
50 struct acpi_device device;
51 struct list_head list_node;
52 u32 system_level;
53 u32 order;
54 unsigned int ref_count;
55 u8 state;
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 const char *resource_dev_name(struct acpi_power_resource *pr)
73{
74 return dev_name(&pr->device.dev);
75}
76
77static inline
78struct acpi_power_resource *to_power_resource(struct acpi_device *device)
79{
80 return container_of(device, struct acpi_power_resource, device);
81}
82
83static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
84{
85 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
86
87 if (!device)
88 return NULL;
89
90 return to_power_resource(device);
91}
92
93static int acpi_power_resources_list_add(acpi_handle handle,
94 struct list_head *list)
95{
96 struct acpi_power_resource *resource = acpi_power_get_context(handle);
97 struct acpi_power_resource_entry *entry;
98
99 if (!resource || !list)
100 return -EINVAL;
101
102 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
103 if (!entry)
104 return -ENOMEM;
105
106 entry->resource = resource;
107 if (!list_empty(list)) {
108 struct acpi_power_resource_entry *e;
109
110 list_for_each_entry(e, list, node)
111 if (e->resource->order > resource->order) {
112 list_add_tail(&entry->node, &e->node);
113 return 0;
114 }
115 }
116 list_add_tail(&entry->node, list);
117 return 0;
118}
119
120void acpi_power_resources_list_free(struct list_head *list)
121{
122 struct acpi_power_resource_entry *entry, *e;
123
124 list_for_each_entry_safe(entry, e, list, node) {
125 list_del(&entry->node);
126 kfree(entry);
127 }
128}
129
130static bool acpi_power_resource_is_dup(union acpi_object *package,
131 unsigned int start, unsigned int i)
132{
133 acpi_handle rhandle, dup;
134 unsigned int j;
135
136 /* The caller is expected to check the package element types */
137 rhandle = package->package.elements[i].reference.handle;
138 for (j = start; j < i; j++) {
139 dup = package->package.elements[j].reference.handle;
140 if (dup == rhandle)
141 return true;
142 }
143
144 return false;
145}
146
147int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
148 struct list_head *list)
149{
150 unsigned int i;
151 int err = 0;
152
153 for (i = start; i < package->package.count; i++) {
154 union acpi_object *element = &package->package.elements[i];
155 struct acpi_device *rdev;
156 acpi_handle rhandle;
157
158 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
159 err = -ENODATA;
160 break;
161 }
162 rhandle = element->reference.handle;
163 if (!rhandle) {
164 err = -ENODEV;
165 break;
166 }
167
168 /* Some ACPI tables contain duplicate power resource references */
169 if (acpi_power_resource_is_dup(package, start, i))
170 continue;
171
172 rdev = acpi_add_power_resource(rhandle);
173 if (!rdev) {
174 err = -ENODEV;
175 break;
176 }
177 err = acpi_power_resources_list_add(rhandle, list);
178 if (err)
179 break;
180 }
181 if (err)
182 acpi_power_resources_list_free(list);
183
184 return err;
185}
186
187static int __get_state(acpi_handle handle, u8 *state)
188{
189 acpi_status status = AE_OK;
190 unsigned long long sta = 0;
191 u8 cur_state;
192
193 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
194 if (ACPI_FAILURE(status))
195 return -ENODEV;
196
197 cur_state = sta & ACPI_POWER_RESOURCE_STATE_ON;
198
199 acpi_handle_debug(handle, "Power resource is %s\n",
200 cur_state ? "on" : "off");
201
202 *state = cur_state;
203 return 0;
204}
205
206static int acpi_power_get_state(struct acpi_power_resource *resource, u8 *state)
207{
208 if (resource->state == ACPI_POWER_RESOURCE_STATE_UNKNOWN) {
209 int ret;
210
211 ret = __get_state(resource->device.handle, &resource->state);
212 if (ret)
213 return ret;
214 }
215
216 *state = resource->state;
217 return 0;
218}
219
220static int acpi_power_get_list_state(struct list_head *list, u8 *state)
221{
222 struct acpi_power_resource_entry *entry;
223 u8 cur_state = ACPI_POWER_RESOURCE_STATE_OFF;
224
225 if (!list || !state)
226 return -EINVAL;
227
228 /* The state of the list is 'on' IFF all resources are 'on'. */
229 list_for_each_entry(entry, list, node) {
230 struct acpi_power_resource *resource = entry->resource;
231 int result;
232
233 mutex_lock(&resource->resource_lock);
234 result = acpi_power_get_state(resource, &cur_state);
235 mutex_unlock(&resource->resource_lock);
236 if (result)
237 return result;
238
239 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
240 break;
241 }
242
243 pr_debug("Power resource list is %s\n", cur_state ? "on" : "off");
244
245 *state = cur_state;
246 return 0;
247}
248
249static int
250acpi_power_resource_add_dependent(struct acpi_power_resource *resource,
251 struct device *dev)
252{
253 struct acpi_power_dependent_device *dep;
254 int ret = 0;
255
256 mutex_lock(&resource->resource_lock);
257 list_for_each_entry(dep, &resource->dependents, node) {
258 /* Only add it once */
259 if (dep->dev == dev)
260 goto unlock;
261 }
262
263 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
264 if (!dep) {
265 ret = -ENOMEM;
266 goto unlock;
267 }
268
269 dep->dev = dev;
270 list_add_tail(&dep->node, &resource->dependents);
271 dev_dbg(dev, "added power dependency to [%s]\n",
272 resource_dev_name(resource));
273
274unlock:
275 mutex_unlock(&resource->resource_lock);
276 return ret;
277}
278
279static void
280acpi_power_resource_remove_dependent(struct acpi_power_resource *resource,
281 struct device *dev)
282{
283 struct acpi_power_dependent_device *dep;
284
285 mutex_lock(&resource->resource_lock);
286 list_for_each_entry(dep, &resource->dependents, node) {
287 if (dep->dev == dev) {
288 list_del(&dep->node);
289 kfree(dep);
290 dev_dbg(dev, "removed power dependency to [%s]\n",
291 resource_dev_name(resource));
292 break;
293 }
294 }
295 mutex_unlock(&resource->resource_lock);
296}
297
298/**
299 * acpi_device_power_add_dependent - Add dependent device of this ACPI device
300 * @adev: ACPI device pointer
301 * @dev: Dependent device
302 *
303 * If @adev has non-empty _PR0 the @dev is added as dependent device to all
304 * power resources returned by it. This means that whenever these power
305 * resources are turned _ON the dependent devices get runtime resumed. This
306 * is needed for devices such as PCI to allow its driver to re-initialize
307 * it after it went to D0uninitialized.
308 *
309 * If @adev does not have _PR0 this does nothing.
310 *
311 * Returns %0 in case of success and negative errno otherwise.
312 */
313int acpi_device_power_add_dependent(struct acpi_device *adev,
314 struct device *dev)
315{
316 struct acpi_power_resource_entry *entry;
317 struct list_head *resources;
318 int ret;
319
320 if (!adev->flags.power_manageable)
321 return 0;
322
323 resources = &adev->power.states[ACPI_STATE_D0].resources;
324 list_for_each_entry(entry, resources, node) {
325 ret = acpi_power_resource_add_dependent(entry->resource, dev);
326 if (ret)
327 goto err;
328 }
329
330 return 0;
331
332err:
333 list_for_each_entry(entry, resources, node)
334 acpi_power_resource_remove_dependent(entry->resource, dev);
335
336 return ret;
337}
338
339/**
340 * acpi_device_power_remove_dependent - Remove dependent device
341 * @adev: ACPI device pointer
342 * @dev: Dependent device
343 *
344 * Does the opposite of acpi_device_power_add_dependent() and removes the
345 * dependent device if it is found. Can be called to @adev that does not
346 * have _PR0 as well.
347 */
348void acpi_device_power_remove_dependent(struct acpi_device *adev,
349 struct device *dev)
350{
351 struct acpi_power_resource_entry *entry;
352 struct list_head *resources;
353
354 if (!adev->flags.power_manageable)
355 return;
356
357 resources = &adev->power.states[ACPI_STATE_D0].resources;
358 list_for_each_entry_reverse(entry, resources, node)
359 acpi_power_resource_remove_dependent(entry->resource, dev);
360}
361
362static int __acpi_power_on(struct acpi_power_resource *resource)
363{
364 acpi_handle handle = resource->device.handle;
365 struct acpi_power_dependent_device *dep;
366 acpi_status status = AE_OK;
367
368 status = acpi_evaluate_object(handle, "_ON", NULL, NULL);
369 if (ACPI_FAILURE(status)) {
370 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
371 return -ENODEV;
372 }
373
374 resource->state = ACPI_POWER_RESOURCE_STATE_ON;
375
376 acpi_handle_debug(handle, "Power resource turned on\n");
377
378 /*
379 * If there are other dependents on this power resource we need to
380 * resume them now so that their drivers can re-initialize the
381 * hardware properly after it went back to D0.
382 */
383 if (list_empty(&resource->dependents) ||
384 list_is_singular(&resource->dependents))
385 return 0;
386
387 list_for_each_entry(dep, &resource->dependents, node) {
388 dev_dbg(dep->dev, "runtime resuming because [%s] turned on\n",
389 resource_dev_name(resource));
390 pm_request_resume(dep->dev);
391 }
392
393 return 0;
394}
395
396static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
397{
398 int result = 0;
399
400 if (resource->ref_count++) {
401 acpi_handle_debug(resource->device.handle,
402 "Power resource already on\n");
403 } else {
404 result = __acpi_power_on(resource);
405 if (result)
406 resource->ref_count--;
407 }
408 return result;
409}
410
411static int acpi_power_on(struct acpi_power_resource *resource)
412{
413 int result;
414
415 mutex_lock(&resource->resource_lock);
416 result = acpi_power_on_unlocked(resource);
417 mutex_unlock(&resource->resource_lock);
418 return result;
419}
420
421static int __acpi_power_off(struct acpi_power_resource *resource)
422{
423 acpi_handle handle = resource->device.handle;
424 acpi_status status;
425
426 status = acpi_evaluate_object(handle, "_OFF", NULL, NULL);
427 if (ACPI_FAILURE(status)) {
428 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
429 return -ENODEV;
430 }
431
432 resource->state = ACPI_POWER_RESOURCE_STATE_OFF;
433
434 acpi_handle_debug(handle, "Power resource turned off\n");
435
436 return 0;
437}
438
439static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
440{
441 int result = 0;
442
443 if (!resource->ref_count) {
444 acpi_handle_debug(resource->device.handle,
445 "Power resource already off\n");
446 return 0;
447 }
448
449 if (--resource->ref_count) {
450 acpi_handle_debug(resource->device.handle,
451 "Power resource still in use\n");
452 } else {
453 result = __acpi_power_off(resource);
454 if (result)
455 resource->ref_count++;
456 }
457 return result;
458}
459
460static int acpi_power_off(struct acpi_power_resource *resource)
461{
462 int result;
463
464 mutex_lock(&resource->resource_lock);
465 result = acpi_power_off_unlocked(resource);
466 mutex_unlock(&resource->resource_lock);
467 return result;
468}
469
470static int acpi_power_off_list(struct list_head *list)
471{
472 struct acpi_power_resource_entry *entry;
473 int result = 0;
474
475 list_for_each_entry_reverse(entry, list, node) {
476 result = acpi_power_off(entry->resource);
477 if (result)
478 goto err;
479 }
480 return 0;
481
482 err:
483 list_for_each_entry_continue(entry, list, node)
484 acpi_power_on(entry->resource);
485
486 return result;
487}
488
489static int acpi_power_on_list(struct list_head *list)
490{
491 struct acpi_power_resource_entry *entry;
492 int result = 0;
493
494 list_for_each_entry(entry, list, node) {
495 result = acpi_power_on(entry->resource);
496 if (result)
497 goto err;
498 }
499 return 0;
500
501 err:
502 list_for_each_entry_continue_reverse(entry, list, node)
503 acpi_power_off(entry->resource);
504
505 return result;
506}
507
508static struct attribute *attrs[] = {
509 NULL,
510};
511
512static const struct attribute_group attr_groups[] = {
513 [ACPI_STATE_D0] = {
514 .name = "power_resources_D0",
515 .attrs = attrs,
516 },
517 [ACPI_STATE_D1] = {
518 .name = "power_resources_D1",
519 .attrs = attrs,
520 },
521 [ACPI_STATE_D2] = {
522 .name = "power_resources_D2",
523 .attrs = attrs,
524 },
525 [ACPI_STATE_D3_HOT] = {
526 .name = "power_resources_D3hot",
527 .attrs = attrs,
528 },
529};
530
531static const struct attribute_group wakeup_attr_group = {
532 .name = "power_resources_wakeup",
533 .attrs = attrs,
534};
535
536static void acpi_power_hide_list(struct acpi_device *adev,
537 struct list_head *resources,
538 const struct attribute_group *attr_group)
539{
540 struct acpi_power_resource_entry *entry;
541
542 if (list_empty(resources))
543 return;
544
545 list_for_each_entry_reverse(entry, resources, node) {
546 struct acpi_device *res_dev = &entry->resource->device;
547
548 sysfs_remove_link_from_group(&adev->dev.kobj,
549 attr_group->name,
550 dev_name(&res_dev->dev));
551 }
552 sysfs_remove_group(&adev->dev.kobj, attr_group);
553}
554
555static void acpi_power_expose_list(struct acpi_device *adev,
556 struct list_head *resources,
557 const struct attribute_group *attr_group)
558{
559 struct acpi_power_resource_entry *entry;
560 int ret;
561
562 if (list_empty(resources))
563 return;
564
565 ret = sysfs_create_group(&adev->dev.kobj, attr_group);
566 if (ret)
567 return;
568
569 list_for_each_entry(entry, resources, node) {
570 struct acpi_device *res_dev = &entry->resource->device;
571
572 ret = sysfs_add_link_to_group(&adev->dev.kobj,
573 attr_group->name,
574 &res_dev->dev.kobj,
575 dev_name(&res_dev->dev));
576 if (ret) {
577 acpi_power_hide_list(adev, resources, attr_group);
578 break;
579 }
580 }
581}
582
583static void acpi_power_expose_hide(struct acpi_device *adev,
584 struct list_head *resources,
585 const struct attribute_group *attr_group,
586 bool expose)
587{
588 if (expose)
589 acpi_power_expose_list(adev, resources, attr_group);
590 else
591 acpi_power_hide_list(adev, resources, attr_group);
592}
593
594void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
595{
596 int state;
597
598 if (adev->wakeup.flags.valid)
599 acpi_power_expose_hide(adev, &adev->wakeup.resources,
600 &wakeup_attr_group, add);
601
602 if (!adev->power.flags.power_resources)
603 return;
604
605 for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
606 acpi_power_expose_hide(adev,
607 &adev->power.states[state].resources,
608 &attr_groups[state], add);
609}
610
611int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
612{
613 struct acpi_power_resource_entry *entry;
614 int system_level = 5;
615
616 list_for_each_entry(entry, list, node) {
617 struct acpi_power_resource *resource = entry->resource;
618 u8 state;
619
620 mutex_lock(&resource->resource_lock);
621
622 /*
623 * Make sure that the power resource state and its reference
624 * counter value are consistent with each other.
625 */
626 if (!resource->ref_count &&
627 !acpi_power_get_state(resource, &state) &&
628 state == ACPI_POWER_RESOURCE_STATE_ON)
629 __acpi_power_off(resource);
630
631 if (system_level > resource->system_level)
632 system_level = resource->system_level;
633
634 mutex_unlock(&resource->resource_lock);
635 }
636 *system_level_p = system_level;
637 return 0;
638}
639
640/* --------------------------------------------------------------------------
641 Device Power Management
642 -------------------------------------------------------------------------- */
643
644/**
645 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
646 * ACPI 3.0) _PSW (Power State Wake)
647 * @dev: Device to handle.
648 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
649 * @sleep_state: Target sleep state of the system.
650 * @dev_state: Target power state of the device.
651 *
652 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
653 * State Wake) for the device, if present. On failure reset the device's
654 * wakeup.flags.valid flag.
655 *
656 * RETURN VALUE:
657 * 0 if either _DSW or _PSW has been successfully executed
658 * 0 if neither _DSW nor _PSW has been found
659 * -ENODEV if the execution of either _DSW or _PSW has failed
660 */
661int acpi_device_sleep_wake(struct acpi_device *dev,
662 int enable, int sleep_state, int dev_state)
663{
664 union acpi_object in_arg[3];
665 struct acpi_object_list arg_list = { 3, in_arg };
666 acpi_status status = AE_OK;
667
668 /*
669 * Try to execute _DSW first.
670 *
671 * Three arguments are needed for the _DSW object:
672 * Argument 0: enable/disable the wake capabilities
673 * Argument 1: target system state
674 * Argument 2: target device state
675 * When _DSW object is called to disable the wake capabilities, maybe
676 * the first argument is filled. The values of the other two arguments
677 * are meaningless.
678 */
679 in_arg[0].type = ACPI_TYPE_INTEGER;
680 in_arg[0].integer.value = enable;
681 in_arg[1].type = ACPI_TYPE_INTEGER;
682 in_arg[1].integer.value = sleep_state;
683 in_arg[2].type = ACPI_TYPE_INTEGER;
684 in_arg[2].integer.value = dev_state;
685 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
686 if (ACPI_SUCCESS(status)) {
687 return 0;
688 } else if (status != AE_NOT_FOUND) {
689 acpi_handle_info(dev->handle, "_DSW execution failed\n");
690 dev->wakeup.flags.valid = 0;
691 return -ENODEV;
692 }
693
694 /* Execute _PSW */
695 status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
696 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
697 acpi_handle_info(dev->handle, "_PSW execution failed\n");
698 dev->wakeup.flags.valid = 0;
699 return -ENODEV;
700 }
701
702 return 0;
703}
704
705/*
706 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
707 * 1. Power on the power resources required for the wakeup device
708 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
709 * State Wake) for the device, if present
710 */
711int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
712{
713 int err = 0;
714
715 if (!dev || !dev->wakeup.flags.valid)
716 return -EINVAL;
717
718 mutex_lock(&acpi_device_lock);
719
720 dev_dbg(&dev->dev, "Enabling wakeup power (count %d)\n",
721 dev->wakeup.prepare_count);
722
723 if (dev->wakeup.prepare_count++)
724 goto out;
725
726 err = acpi_power_on_list(&dev->wakeup.resources);
727 if (err) {
728 dev_err(&dev->dev, "Cannot turn on wakeup power resources\n");
729 dev->wakeup.flags.valid = 0;
730 goto out;
731 }
732
733 /*
734 * Passing 3 as the third argument below means the device may be
735 * put into arbitrary power state afterward.
736 */
737 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
738 if (err) {
739 acpi_power_off_list(&dev->wakeup.resources);
740 dev->wakeup.prepare_count = 0;
741 goto out;
742 }
743
744 dev_dbg(&dev->dev, "Wakeup power enabled\n");
745
746 out:
747 mutex_unlock(&acpi_device_lock);
748 return err;
749}
750
751/*
752 * Shutdown a wakeup device, counterpart of above method
753 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
754 * State Wake) for the device, if present
755 * 2. Shutdown down the power resources
756 */
757int acpi_disable_wakeup_device_power(struct acpi_device *dev)
758{
759 struct acpi_power_resource_entry *entry;
760 int err = 0;
761
762 if (!dev || !dev->wakeup.flags.valid)
763 return -EINVAL;
764
765 mutex_lock(&acpi_device_lock);
766
767 dev_dbg(&dev->dev, "Disabling wakeup power (count %d)\n",
768 dev->wakeup.prepare_count);
769
770 /* Do nothing if wakeup power has not been enabled for this device. */
771 if (dev->wakeup.prepare_count <= 0)
772 goto out;
773
774 if (--dev->wakeup.prepare_count > 0)
775 goto out;
776
777 err = acpi_device_sleep_wake(dev, 0, 0, 0);
778 if (err)
779 goto out;
780
781 /*
782 * All of the power resources in the list need to be turned off even if
783 * there are errors.
784 */
785 list_for_each_entry(entry, &dev->wakeup.resources, node) {
786 int ret;
787
788 ret = acpi_power_off(entry->resource);
789 if (ret && !err)
790 err = ret;
791 }
792 if (err) {
793 dev_err(&dev->dev, "Cannot turn off wakeup power resources\n");
794 dev->wakeup.flags.valid = 0;
795 goto out;
796 }
797
798 dev_dbg(&dev->dev, "Wakeup power disabled\n");
799
800 out:
801 mutex_unlock(&acpi_device_lock);
802 return err;
803}
804
805int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
806{
807 u8 list_state = ACPI_POWER_RESOURCE_STATE_OFF;
808 int result = 0;
809 int i = 0;
810
811 if (!device || !state)
812 return -EINVAL;
813
814 /*
815 * We know a device's inferred power state when all the resources
816 * required for a given D-state are 'on'.
817 */
818 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
819 struct list_head *list = &device->power.states[i].resources;
820
821 if (list_empty(list))
822 continue;
823
824 result = acpi_power_get_list_state(list, &list_state);
825 if (result)
826 return result;
827
828 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
829 *state = i;
830 return 0;
831 }
832 }
833
834 *state = device->power.states[ACPI_STATE_D3_COLD].flags.valid ?
835 ACPI_STATE_D3_COLD : ACPI_STATE_D3_HOT;
836 return 0;
837}
838
839int acpi_power_on_resources(struct acpi_device *device, int state)
840{
841 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
842 return -EINVAL;
843
844 return acpi_power_on_list(&device->power.states[state].resources);
845}
846
847int acpi_power_transition(struct acpi_device *device, int state)
848{
849 int result = 0;
850
851 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
852 return -EINVAL;
853
854 if (device->power.state == state || !device->flags.power_manageable)
855 return 0;
856
857 if ((device->power.state < ACPI_STATE_D0)
858 || (device->power.state > ACPI_STATE_D3_COLD))
859 return -ENODEV;
860
861 /*
862 * First we reference all power resources required in the target list
863 * (e.g. so the device doesn't lose power while transitioning). Then,
864 * we dereference all power resources used in the current list.
865 */
866 if (state < ACPI_STATE_D3_COLD)
867 result = acpi_power_on_list(
868 &device->power.states[state].resources);
869
870 if (!result && device->power.state < ACPI_STATE_D3_COLD)
871 acpi_power_off_list(
872 &device->power.states[device->power.state].resources);
873
874 /* We shouldn't change the state unless the above operations succeed. */
875 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
876
877 return result;
878}
879
880static void acpi_release_power_resource(struct device *dev)
881{
882 struct acpi_device *device = to_acpi_device(dev);
883 struct acpi_power_resource *resource;
884
885 resource = container_of(device, struct acpi_power_resource, device);
886
887 mutex_lock(&power_resource_list_lock);
888 list_del(&resource->list_node);
889 mutex_unlock(&power_resource_list_lock);
890
891 acpi_free_pnp_ids(&device->pnp);
892 kfree(resource);
893}
894
895static ssize_t resource_in_use_show(struct device *dev,
896 struct device_attribute *attr,
897 char *buf)
898{
899 struct acpi_power_resource *resource;
900
901 resource = to_power_resource(to_acpi_device(dev));
902 return sprintf(buf, "%u\n", !!resource->ref_count);
903}
904static DEVICE_ATTR_RO(resource_in_use);
905
906static void acpi_power_sysfs_remove(struct acpi_device *device)
907{
908 device_remove_file(&device->dev, &dev_attr_resource_in_use);
909}
910
911static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource)
912{
913 mutex_lock(&power_resource_list_lock);
914
915 if (!list_empty(&acpi_power_resource_list)) {
916 struct acpi_power_resource *r;
917
918 list_for_each_entry(r, &acpi_power_resource_list, list_node)
919 if (r->order > resource->order) {
920 list_add_tail(&resource->list_node, &r->list_node);
921 goto out;
922 }
923 }
924 list_add_tail(&resource->list_node, &acpi_power_resource_list);
925
926 out:
927 mutex_unlock(&power_resource_list_lock);
928}
929
930struct acpi_device *acpi_add_power_resource(acpi_handle handle)
931{
932 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
933 struct acpi_power_resource *resource;
934 union acpi_object acpi_object;
935 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
936 acpi_status status;
937 u8 state_dummy;
938 int result;
939
940 if (device)
941 return device;
942
943 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
944 if (!resource)
945 return NULL;
946
947 device = &resource->device;
948 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
949 acpi_release_power_resource);
950 mutex_init(&resource->resource_lock);
951 INIT_LIST_HEAD(&resource->list_node);
952 INIT_LIST_HEAD(&resource->dependents);
953 strscpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
954 strscpy(acpi_device_class(device), ACPI_POWER_CLASS);
955 device->power.state = ACPI_STATE_UNKNOWN;
956 device->flags.match_driver = true;
957
958 /* Evaluate the object to get the system level and resource order. */
959 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
960 if (ACPI_FAILURE(status))
961 goto err;
962
963 resource->system_level = acpi_object.power_resource.system_level;
964 resource->order = acpi_object.power_resource.resource_order;
965 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
966
967 /* Get the initial state or just flip it on if that fails. */
968 if (acpi_power_get_state(resource, &state_dummy))
969 __acpi_power_on(resource);
970
971 acpi_handle_info(handle, "New power resource\n");
972
973 result = acpi_tie_acpi_dev(device);
974 if (result)
975 goto err;
976
977 result = acpi_device_add(device);
978 if (result)
979 goto err;
980
981 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
982 device->remove = acpi_power_sysfs_remove;
983
984 acpi_power_add_resource_to_list(resource);
985 acpi_device_add_finalize(device);
986 return device;
987
988 err:
989 acpi_release_power_resource(&device->dev);
990 return NULL;
991}
992
993#ifdef CONFIG_ACPI_SLEEP
994void acpi_resume_power_resources(void)
995{
996 struct acpi_power_resource *resource;
997
998 mutex_lock(&power_resource_list_lock);
999
1000 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
1001 int result;
1002 u8 state;
1003
1004 mutex_lock(&resource->resource_lock);
1005
1006 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
1007 result = acpi_power_get_state(resource, &state);
1008 if (result) {
1009 mutex_unlock(&resource->resource_lock);
1010 continue;
1011 }
1012
1013 if (state == ACPI_POWER_RESOURCE_STATE_OFF
1014 && resource->ref_count) {
1015 acpi_handle_debug(resource->device.handle, "Turning ON\n");
1016 __acpi_power_on(resource);
1017 }
1018
1019 mutex_unlock(&resource->resource_lock);
1020 }
1021
1022 mutex_unlock(&power_resource_list_lock);
1023}
1024#endif
1025
1026static const struct dmi_system_id dmi_leave_unused_power_resources_on[] = {
1027 {
1028 /*
1029 * The Toshiba Click Mini has a CPR3 power-resource which must
1030 * be on for the touchscreen to work, but which is not in any
1031 * _PR? lists. The other 2 affected power-resources are no-ops.
1032 */
1033 .matches = {
1034 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
1035 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE Click Mini L9W-B"),
1036 },
1037 },
1038 {}
1039};
1040
1041/**
1042 * acpi_turn_off_unused_power_resources - Turn off power resources not in use.
1043 */
1044void acpi_turn_off_unused_power_resources(void)
1045{
1046 struct acpi_power_resource *resource;
1047
1048 if (dmi_check_system(dmi_leave_unused_power_resources_on))
1049 return;
1050
1051 mutex_lock(&power_resource_list_lock);
1052
1053 list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
1054 mutex_lock(&resource->resource_lock);
1055
1056 if (!resource->ref_count &&
1057 resource->state == ACPI_POWER_RESOURCE_STATE_ON) {
1058 acpi_handle_debug(resource->device.handle, "Turning OFF\n");
1059 __acpi_power_off(resource);
1060 }
1061
1062 mutex_unlock(&resource->resource_lock);
1063 }
1064
1065 mutex_unlock(&power_resource_list_lock);
1066}
1/*
2 * acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
3 *
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 *
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24 */
25
26/*
27 * ACPI power-managed devices may be controlled in two ways:
28 * 1. via "Device Specific (D-State) Control"
29 * 2. via "Power Resource Control".
30 * This module is used to manage devices relying on Power Resource Control.
31 *
32 * An ACPI "power resource object" describes a software controllable power
33 * plane, clock plane, or other resource used by a power managed device.
34 * A device may rely on multiple power resources, and a power resource
35 * may be shared by multiple devices.
36 */
37
38#include <linux/kernel.h>
39#include <linux/module.h>
40#include <linux/init.h>
41#include <linux/types.h>
42#include <linux/slab.h>
43#include <linux/pm_runtime.h>
44#include <linux/sysfs.h>
45#include <linux/acpi.h>
46#include "sleep.h"
47#include "internal.h"
48
49#define _COMPONENT ACPI_POWER_COMPONENT
50ACPI_MODULE_NAME("power");
51#define ACPI_POWER_CLASS "power_resource"
52#define ACPI_POWER_DEVICE_NAME "Power Resource"
53#define ACPI_POWER_FILE_INFO "info"
54#define ACPI_POWER_FILE_STATUS "state"
55#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
56#define ACPI_POWER_RESOURCE_STATE_ON 0x01
57#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
58
59struct acpi_power_resource {
60 struct acpi_device device;
61 struct list_head list_node;
62 char *name;
63 u32 system_level;
64 u32 order;
65 unsigned int ref_count;
66 bool wakeup_enabled;
67 struct mutex resource_lock;
68};
69
70struct acpi_power_resource_entry {
71 struct list_head node;
72 struct acpi_power_resource *resource;
73};
74
75static LIST_HEAD(acpi_power_resource_list);
76static DEFINE_MUTEX(power_resource_list_lock);
77
78/* --------------------------------------------------------------------------
79 Power Resource Management
80 -------------------------------------------------------------------------- */
81
82static inline
83struct acpi_power_resource *to_power_resource(struct acpi_device *device)
84{
85 return container_of(device, struct acpi_power_resource, device);
86}
87
88static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
89{
90 struct acpi_device *device;
91
92 if (acpi_bus_get_device(handle, &device))
93 return NULL;
94
95 return to_power_resource(device);
96}
97
98static int acpi_power_resources_list_add(acpi_handle handle,
99 struct list_head *list)
100{
101 struct acpi_power_resource *resource = acpi_power_get_context(handle);
102 struct acpi_power_resource_entry *entry;
103
104 if (!resource || !list)
105 return -EINVAL;
106
107 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
108 if (!entry)
109 return -ENOMEM;
110
111 entry->resource = resource;
112 if (!list_empty(list)) {
113 struct acpi_power_resource_entry *e;
114
115 list_for_each_entry(e, list, node)
116 if (e->resource->order > resource->order) {
117 list_add_tail(&entry->node, &e->node);
118 return 0;
119 }
120 }
121 list_add_tail(&entry->node, list);
122 return 0;
123}
124
125void acpi_power_resources_list_free(struct list_head *list)
126{
127 struct acpi_power_resource_entry *entry, *e;
128
129 list_for_each_entry_safe(entry, e, list, node) {
130 list_del(&entry->node);
131 kfree(entry);
132 }
133}
134
135int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
136 struct list_head *list)
137{
138 unsigned int i;
139 int err = 0;
140
141 for (i = start; i < package->package.count; i++) {
142 union acpi_object *element = &package->package.elements[i];
143 acpi_handle rhandle;
144
145 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
146 err = -ENODATA;
147 break;
148 }
149 rhandle = element->reference.handle;
150 if (!rhandle) {
151 err = -ENODEV;
152 break;
153 }
154 err = acpi_add_power_resource(rhandle);
155 if (err)
156 break;
157
158 err = acpi_power_resources_list_add(rhandle, list);
159 if (err)
160 break;
161 }
162 if (err)
163 acpi_power_resources_list_free(list);
164
165 return err;
166}
167
168static int acpi_power_get_state(acpi_handle handle, int *state)
169{
170 acpi_status status = AE_OK;
171 unsigned long long sta = 0;
172 char node_name[5];
173 struct acpi_buffer buffer = { sizeof(node_name), node_name };
174
175
176 if (!handle || !state)
177 return -EINVAL;
178
179 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
180 if (ACPI_FAILURE(status))
181 return -ENODEV;
182
183 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
184 ACPI_POWER_RESOURCE_STATE_OFF;
185
186 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
187
188 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
189 node_name,
190 *state ? "on" : "off"));
191
192 return 0;
193}
194
195static int acpi_power_get_list_state(struct list_head *list, int *state)
196{
197 struct acpi_power_resource_entry *entry;
198 int cur_state;
199
200 if (!list || !state)
201 return -EINVAL;
202
203 /* The state of the list is 'on' IFF all resources are 'on'. */
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 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 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 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 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 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 = ACPI_STATE_D3_COLD;
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 /* TBD: Resources must be ordered. */
714
715 /*
716 * First we reference all power resources required in the target list
717 * (e.g. so the device doesn't lose power while transitioning). Then,
718 * we dereference all power resources used in the current list.
719 */
720 if (state < ACPI_STATE_D3_COLD)
721 result = acpi_power_on_list(
722 &device->power.states[state].resources);
723
724 if (!result && device->power.state < ACPI_STATE_D3_COLD)
725 acpi_power_off_list(
726 &device->power.states[device->power.state].resources);
727
728 /* We shouldn't change the state unless the above operations succeed. */
729 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
730
731 return result;
732}
733
734static void acpi_release_power_resource(struct device *dev)
735{
736 struct acpi_device *device = to_acpi_device(dev);
737 struct acpi_power_resource *resource;
738
739 resource = container_of(device, struct acpi_power_resource, device);
740
741 mutex_lock(&power_resource_list_lock);
742 list_del(&resource->list_node);
743 mutex_unlock(&power_resource_list_lock);
744
745 acpi_free_pnp_ids(&device->pnp);
746 kfree(resource);
747}
748
749static ssize_t acpi_power_in_use_show(struct device *dev,
750 struct device_attribute *attr,
751 char *buf) {
752 struct acpi_power_resource *resource;
753
754 resource = to_power_resource(to_acpi_device(dev));
755 return sprintf(buf, "%u\n", !!resource->ref_count);
756}
757static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
758
759static void acpi_power_sysfs_remove(struct acpi_device *device)
760{
761 device_remove_file(&device->dev, &dev_attr_resource_in_use);
762}
763
764int acpi_add_power_resource(acpi_handle handle)
765{
766 struct acpi_power_resource *resource;
767 struct acpi_device *device = NULL;
768 union acpi_object acpi_object;
769 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
770 acpi_status status;
771 int state, result = -ENODEV;
772
773 acpi_bus_get_device(handle, &device);
774 if (device)
775 return 0;
776
777 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
778 if (!resource)
779 return -ENOMEM;
780
781 device = &resource->device;
782 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
783 ACPI_STA_DEFAULT);
784 mutex_init(&resource->resource_lock);
785 INIT_LIST_HEAD(&resource->list_node);
786 resource->name = device->pnp.bus_id;
787 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
788 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
789 device->power.state = ACPI_STATE_UNKNOWN;
790
791 /* Evalute the object to get the system level and resource order. */
792 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
793 if (ACPI_FAILURE(status))
794 goto err;
795
796 resource->system_level = acpi_object.power_resource.system_level;
797 resource->order = acpi_object.power_resource.resource_order;
798
799 result = acpi_power_get_state(handle, &state);
800 if (result)
801 goto err;
802
803 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
804 acpi_device_bid(device), state ? "on" : "off");
805
806 device->flags.match_driver = true;
807 result = acpi_device_add(device, acpi_release_power_resource);
808 if (result)
809 goto err;
810
811 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
812 device->remove = acpi_power_sysfs_remove;
813
814 mutex_lock(&power_resource_list_lock);
815 list_add(&resource->list_node, &acpi_power_resource_list);
816 mutex_unlock(&power_resource_list_lock);
817 acpi_device_add_finalize(device);
818 return 0;
819
820 err:
821 acpi_release_power_resource(&device->dev);
822 return result;
823}
824
825#ifdef CONFIG_ACPI_SLEEP
826void acpi_resume_power_resources(void)
827{
828 struct acpi_power_resource *resource;
829
830 mutex_lock(&power_resource_list_lock);
831
832 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
833 int result, state;
834
835 mutex_lock(&resource->resource_lock);
836
837 result = acpi_power_get_state(resource->device.handle, &state);
838 if (result) {
839 mutex_unlock(&resource->resource_lock);
840 continue;
841 }
842
843 if (state == ACPI_POWER_RESOURCE_STATE_OFF
844 && resource->ref_count) {
845 dev_info(&resource->device.dev, "Turning ON\n");
846 __acpi_power_on(resource);
847 } else if (state == ACPI_POWER_RESOURCE_STATE_ON
848 && !resource->ref_count) {
849 dev_info(&resource->device.dev, "Turning OFF\n");
850 __acpi_power_off(resource);
851 }
852
853 mutex_unlock(&resource->resource_lock);
854 }
855
856 mutex_unlock(&power_resource_list_lock);
857}
858#endif