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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 <acpi/acpi_bus.h>
44#include <acpi/acpi_drivers.h>
45#include "sleep.h"
46
47#define PREFIX "ACPI: "
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
59static int acpi_power_add(struct acpi_device *device);
60static int acpi_power_remove(struct acpi_device *device, int type);
61static int acpi_power_resume(struct acpi_device *device);
62
63static const struct acpi_device_id power_device_ids[] = {
64 {ACPI_POWER_HID, 0},
65 {"", 0},
66};
67MODULE_DEVICE_TABLE(acpi, power_device_ids);
68
69static struct acpi_driver acpi_power_driver = {
70 .name = "power",
71 .class = ACPI_POWER_CLASS,
72 .ids = power_device_ids,
73 .ops = {
74 .add = acpi_power_add,
75 .remove = acpi_power_remove,
76 .resume = acpi_power_resume,
77 },
78};
79
80struct acpi_power_resource {
81 struct acpi_device * device;
82 acpi_bus_id name;
83 u32 system_level;
84 u32 order;
85 unsigned int ref_count;
86 struct mutex resource_lock;
87};
88
89static struct list_head acpi_power_resource_list;
90
91/* --------------------------------------------------------------------------
92 Power Resource Management
93 -------------------------------------------------------------------------- */
94
95static int
96acpi_power_get_context(acpi_handle handle,
97 struct acpi_power_resource **resource)
98{
99 int result = 0;
100 struct acpi_device *device = NULL;
101
102
103 if (!resource)
104 return -ENODEV;
105
106 result = acpi_bus_get_device(handle, &device);
107 if (result) {
108 printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle);
109 return result;
110 }
111
112 *resource = acpi_driver_data(device);
113 if (!*resource)
114 return -ENODEV;
115
116 return 0;
117}
118
119static int acpi_power_get_state(acpi_handle handle, int *state)
120{
121 acpi_status status = AE_OK;
122 unsigned long long sta = 0;
123 char node_name[5];
124 struct acpi_buffer buffer = { sizeof(node_name), node_name };
125
126
127 if (!handle || !state)
128 return -EINVAL;
129
130 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
131 if (ACPI_FAILURE(status))
132 return -ENODEV;
133
134 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
135 ACPI_POWER_RESOURCE_STATE_OFF;
136
137 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
138
139 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
140 node_name,
141 *state ? "on" : "off"));
142
143 return 0;
144}
145
146static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
147{
148 int cur_state;
149 int i = 0;
150
151 if (!list || !state)
152 return -EINVAL;
153
154 /* The state of the list is 'on' IFF all resources are 'on'. */
155
156 for (i = 0; i < list->count; i++) {
157 struct acpi_power_resource *resource;
158 acpi_handle handle = list->handles[i];
159 int result;
160
161 result = acpi_power_get_context(handle, &resource);
162 if (result)
163 return result;
164
165 mutex_lock(&resource->resource_lock);
166
167 result = acpi_power_get_state(handle, &cur_state);
168
169 mutex_unlock(&resource->resource_lock);
170
171 if (result)
172 return result;
173
174 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
175 break;
176 }
177
178 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
179 cur_state ? "on" : "off"));
180
181 *state = cur_state;
182
183 return 0;
184}
185
186static int __acpi_power_on(struct acpi_power_resource *resource)
187{
188 acpi_status status = AE_OK;
189
190 status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
191 if (ACPI_FAILURE(status))
192 return -ENODEV;
193
194 /* Update the power resource's _device_ power state */
195 resource->device->power.state = ACPI_STATE_D0;
196
197 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
198 resource->name));
199
200 return 0;
201}
202
203static int acpi_power_on(acpi_handle handle)
204{
205 int result = 0;
206 struct acpi_power_resource *resource = NULL;
207
208 result = acpi_power_get_context(handle, &resource);
209 if (result)
210 return result;
211
212 mutex_lock(&resource->resource_lock);
213
214 if (resource->ref_count++) {
215 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
216 "Power resource [%s] already on",
217 resource->name));
218 } else {
219 result = __acpi_power_on(resource);
220 if (result)
221 resource->ref_count--;
222 }
223
224 mutex_unlock(&resource->resource_lock);
225
226 return result;
227}
228
229static int acpi_power_off(acpi_handle handle)
230{
231 int result = 0;
232 acpi_status status = AE_OK;
233 struct acpi_power_resource *resource = NULL;
234
235 result = acpi_power_get_context(handle, &resource);
236 if (result)
237 return result;
238
239 mutex_lock(&resource->resource_lock);
240
241 if (!resource->ref_count) {
242 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
243 "Power resource [%s] already off",
244 resource->name));
245 goto unlock;
246 }
247
248 if (--resource->ref_count) {
249 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
250 "Power resource [%s] still in use\n",
251 resource->name));
252 goto unlock;
253 }
254
255 status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
256 if (ACPI_FAILURE(status)) {
257 result = -ENODEV;
258 } else {
259 /* Update the power resource's _device_ power state */
260 resource->device->power.state = ACPI_STATE_D3;
261
262 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
263 "Power resource [%s] turned off\n",
264 resource->name));
265 }
266
267 unlock:
268 mutex_unlock(&resource->resource_lock);
269
270 return result;
271}
272
273static void __acpi_power_off_list(struct acpi_handle_list *list, int num_res)
274{
275 int i;
276
277 for (i = num_res - 1; i >= 0 ; i--)
278 acpi_power_off(list->handles[i]);
279}
280
281static void acpi_power_off_list(struct acpi_handle_list *list)
282{
283 __acpi_power_off_list(list, list->count);
284}
285
286static int acpi_power_on_list(struct acpi_handle_list *list)
287{
288 int result = 0;
289 int i;
290
291 for (i = 0; i < list->count; i++) {
292 result = acpi_power_on(list->handles[i]);
293 if (result) {
294 __acpi_power_off_list(list, i);
295 break;
296 }
297 }
298
299 return result;
300}
301
302/**
303 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
304 * ACPI 3.0) _PSW (Power State Wake)
305 * @dev: Device to handle.
306 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
307 * @sleep_state: Target sleep state of the system.
308 * @dev_state: Target power state of the device.
309 *
310 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
311 * State Wake) for the device, if present. On failure reset the device's
312 * wakeup.flags.valid flag.
313 *
314 * RETURN VALUE:
315 * 0 if either _DSW or _PSW has been successfully executed
316 * 0 if neither _DSW nor _PSW has been found
317 * -ENODEV if the execution of either _DSW or _PSW has failed
318 */
319int acpi_device_sleep_wake(struct acpi_device *dev,
320 int enable, int sleep_state, int dev_state)
321{
322 union acpi_object in_arg[3];
323 struct acpi_object_list arg_list = { 3, in_arg };
324 acpi_status status = AE_OK;
325
326 /*
327 * Try to execute _DSW first.
328 *
329 * Three agruments are needed for the _DSW object:
330 * Argument 0: enable/disable the wake capabilities
331 * Argument 1: target system state
332 * Argument 2: target device state
333 * When _DSW object is called to disable the wake capabilities, maybe
334 * the first argument is filled. The values of the other two agruments
335 * are meaningless.
336 */
337 in_arg[0].type = ACPI_TYPE_INTEGER;
338 in_arg[0].integer.value = enable;
339 in_arg[1].type = ACPI_TYPE_INTEGER;
340 in_arg[1].integer.value = sleep_state;
341 in_arg[2].type = ACPI_TYPE_INTEGER;
342 in_arg[2].integer.value = dev_state;
343 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
344 if (ACPI_SUCCESS(status)) {
345 return 0;
346 } else if (status != AE_NOT_FOUND) {
347 printk(KERN_ERR PREFIX "_DSW execution failed\n");
348 dev->wakeup.flags.valid = 0;
349 return -ENODEV;
350 }
351
352 /* Execute _PSW */
353 arg_list.count = 1;
354 in_arg[0].integer.value = enable;
355 status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
356 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
357 printk(KERN_ERR PREFIX "_PSW execution failed\n");
358 dev->wakeup.flags.valid = 0;
359 return -ENODEV;
360 }
361
362 return 0;
363}
364
365/*
366 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
367 * 1. Power on the power resources required for the wakeup device
368 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
369 * State Wake) for the device, if present
370 */
371int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
372{
373 int i, err = 0;
374
375 if (!dev || !dev->wakeup.flags.valid)
376 return -EINVAL;
377
378 mutex_lock(&acpi_device_lock);
379
380 if (dev->wakeup.prepare_count++)
381 goto out;
382
383 /* Open power resource */
384 for (i = 0; i < dev->wakeup.resources.count; i++) {
385 int ret = acpi_power_on(dev->wakeup.resources.handles[i]);
386 if (ret) {
387 printk(KERN_ERR PREFIX "Transition power state\n");
388 dev->wakeup.flags.valid = 0;
389 err = -ENODEV;
390 goto err_out;
391 }
392 }
393
394 /*
395 * Passing 3 as the third argument below means the device may be placed
396 * in arbitrary power state afterwards.
397 */
398 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
399
400 err_out:
401 if (err)
402 dev->wakeup.prepare_count = 0;
403
404 out:
405 mutex_unlock(&acpi_device_lock);
406 return err;
407}
408
409/*
410 * Shutdown a wakeup device, counterpart of above method
411 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
412 * State Wake) for the device, if present
413 * 2. Shutdown down the power resources
414 */
415int acpi_disable_wakeup_device_power(struct acpi_device *dev)
416{
417 int i, err = 0;
418
419 if (!dev || !dev->wakeup.flags.valid)
420 return -EINVAL;
421
422 mutex_lock(&acpi_device_lock);
423
424 if (--dev->wakeup.prepare_count > 0)
425 goto out;
426
427 /*
428 * Executing the code below even if prepare_count is already zero when
429 * the function is called may be useful, for example for initialisation.
430 */
431 if (dev->wakeup.prepare_count < 0)
432 dev->wakeup.prepare_count = 0;
433
434 err = acpi_device_sleep_wake(dev, 0, 0, 0);
435 if (err)
436 goto out;
437
438 /* Close power resource */
439 for (i = 0; i < dev->wakeup.resources.count; i++) {
440 int ret = acpi_power_off(dev->wakeup.resources.handles[i]);
441 if (ret) {
442 printk(KERN_ERR PREFIX "Transition power state\n");
443 dev->wakeup.flags.valid = 0;
444 err = -ENODEV;
445 goto out;
446 }
447 }
448
449 out:
450 mutex_unlock(&acpi_device_lock);
451 return err;
452}
453
454/* --------------------------------------------------------------------------
455 Device Power Management
456 -------------------------------------------------------------------------- */
457
458int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
459{
460 int result = 0;
461 struct acpi_handle_list *list = NULL;
462 int list_state = 0;
463 int i = 0;
464
465 if (!device || !state)
466 return -EINVAL;
467
468 /*
469 * We know a device's inferred power state when all the resources
470 * required for a given D-state are 'on'.
471 */
472 for (i = ACPI_STATE_D0; i < ACPI_STATE_D3; i++) {
473 list = &device->power.states[i].resources;
474 if (list->count < 1)
475 continue;
476
477 result = acpi_power_get_list_state(list, &list_state);
478 if (result)
479 return result;
480
481 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
482 *state = i;
483 return 0;
484 }
485 }
486
487 *state = ACPI_STATE_D3;
488 return 0;
489}
490
491int acpi_power_on_resources(struct acpi_device *device, int state)
492{
493 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3)
494 return -EINVAL;
495
496 return acpi_power_on_list(&device->power.states[state].resources);
497}
498
499int acpi_power_transition(struct acpi_device *device, int state)
500{
501 int result;
502
503 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
504 return -EINVAL;
505
506 if (device->power.state == state)
507 return 0;
508
509 if ((device->power.state < ACPI_STATE_D0)
510 || (device->power.state > ACPI_STATE_D3))
511 return -ENODEV;
512
513 /* TBD: Resources must be ordered. */
514
515 /*
516 * First we reference all power resources required in the target list
517 * (e.g. so the device doesn't lose power while transitioning). Then,
518 * we dereference all power resources used in the current list.
519 */
520 result = acpi_power_on_list(&device->power.states[state].resources);
521 if (!result)
522 acpi_power_off_list(
523 &device->power.states[device->power.state].resources);
524
525 /* We shouldn't change the state unless the above operations succeed. */
526 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
527
528 return result;
529}
530
531/* --------------------------------------------------------------------------
532 Driver Interface
533 -------------------------------------------------------------------------- */
534
535static int acpi_power_add(struct acpi_device *device)
536{
537 int result = 0, state;
538 acpi_status status = AE_OK;
539 struct acpi_power_resource *resource = NULL;
540 union acpi_object acpi_object;
541 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
542
543
544 if (!device)
545 return -EINVAL;
546
547 resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
548 if (!resource)
549 return -ENOMEM;
550
551 resource->device = device;
552 mutex_init(&resource->resource_lock);
553 strcpy(resource->name, device->pnp.bus_id);
554 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
555 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
556 device->driver_data = resource;
557
558 /* Evalute the object to get the system level and resource order. */
559 status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer);
560 if (ACPI_FAILURE(status)) {
561 result = -ENODEV;
562 goto end;
563 }
564 resource->system_level = acpi_object.power_resource.system_level;
565 resource->order = acpi_object.power_resource.resource_order;
566
567 result = acpi_power_get_state(device->handle, &state);
568 if (result)
569 goto end;
570
571 switch (state) {
572 case ACPI_POWER_RESOURCE_STATE_ON:
573 device->power.state = ACPI_STATE_D0;
574 break;
575 case ACPI_POWER_RESOURCE_STATE_OFF:
576 device->power.state = ACPI_STATE_D3;
577 break;
578 default:
579 device->power.state = ACPI_STATE_UNKNOWN;
580 break;
581 }
582
583 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
584 acpi_device_bid(device), state ? "on" : "off");
585
586 end:
587 if (result)
588 kfree(resource);
589
590 return result;
591}
592
593static int acpi_power_remove(struct acpi_device *device, int type)
594{
595 struct acpi_power_resource *resource;
596
597 if (!device)
598 return -EINVAL;
599
600 resource = acpi_driver_data(device);
601 if (!resource)
602 return -EINVAL;
603
604 kfree(resource);
605
606 return 0;
607}
608
609static int acpi_power_resume(struct acpi_device *device)
610{
611 int result = 0, state;
612 struct acpi_power_resource *resource;
613
614 if (!device)
615 return -EINVAL;
616
617 resource = acpi_driver_data(device);
618 if (!resource)
619 return -EINVAL;
620
621 mutex_lock(&resource->resource_lock);
622
623 result = acpi_power_get_state(device->handle, &state);
624 if (result)
625 goto unlock;
626
627 if (state == ACPI_POWER_RESOURCE_STATE_OFF && resource->ref_count)
628 result = __acpi_power_on(resource);
629
630 unlock:
631 mutex_unlock(&resource->resource_lock);
632
633 return result;
634}
635
636int __init acpi_power_init(void)
637{
638 INIT_LIST_HEAD(&acpi_power_resource_list);
639 return acpi_bus_register_driver(&acpi_power_driver);
640}
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/kernel.h>
27#include <linux/module.h>
28#include <linux/init.h>
29#include <linux/types.h>
30#include <linux/slab.h>
31#include <linux/pm_runtime.h>
32#include <linux/sysfs.h>
33#include <linux/acpi.h>
34#include "sleep.h"
35#include "internal.h"
36
37#define ACPI_POWER_CLASS "power_resource"
38#define ACPI_POWER_DEVICE_NAME "Power Resource"
39#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
40#define ACPI_POWER_RESOURCE_STATE_ON 0x01
41#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
42
43struct acpi_power_dependent_device {
44 struct device *dev;
45 struct list_head node;
46};
47
48struct acpi_power_resource {
49 struct acpi_device device;
50 struct list_head list_node;
51 u32 system_level;
52 u32 order;
53 unsigned int ref_count;
54 u8 state;
55 struct mutex resource_lock;
56 struct list_head dependents;
57};
58
59struct acpi_power_resource_entry {
60 struct list_head node;
61 struct acpi_power_resource *resource;
62};
63
64static LIST_HEAD(acpi_power_resource_list);
65static DEFINE_MUTEX(power_resource_list_lock);
66
67/* --------------------------------------------------------------------------
68 Power Resource Management
69 -------------------------------------------------------------------------- */
70
71static inline const char *resource_dev_name(struct acpi_power_resource *pr)
72{
73 return dev_name(&pr->device.dev);
74}
75
76static inline
77struct acpi_power_resource *to_power_resource(struct acpi_device *device)
78{
79 return container_of(device, struct acpi_power_resource, device);
80}
81
82static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
83{
84 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
85
86 if (!device)
87 return NULL;
88
89 return to_power_resource(device);
90}
91
92static int acpi_power_resources_list_add(acpi_handle handle,
93 struct list_head *list)
94{
95 struct acpi_power_resource *resource = acpi_power_get_context(handle);
96 struct acpi_power_resource_entry *entry;
97
98 if (!resource || !list)
99 return -EINVAL;
100
101 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
102 if (!entry)
103 return -ENOMEM;
104
105 entry->resource = resource;
106 if (!list_empty(list)) {
107 struct acpi_power_resource_entry *e;
108
109 list_for_each_entry(e, list, node)
110 if (e->resource->order > resource->order) {
111 list_add_tail(&entry->node, &e->node);
112 return 0;
113 }
114 }
115 list_add_tail(&entry->node, list);
116 return 0;
117}
118
119void acpi_power_resources_list_free(struct list_head *list)
120{
121 struct acpi_power_resource_entry *entry, *e;
122
123 list_for_each_entry_safe(entry, e, list, node) {
124 list_del(&entry->node);
125 kfree(entry);
126 }
127}
128
129static bool acpi_power_resource_is_dup(union acpi_object *package,
130 unsigned int start, unsigned int i)
131{
132 acpi_handle rhandle, dup;
133 unsigned int j;
134
135 /* The caller is expected to check the package element types */
136 rhandle = package->package.elements[i].reference.handle;
137 for (j = start; j < i; j++) {
138 dup = package->package.elements[j].reference.handle;
139 if (dup == rhandle)
140 return true;
141 }
142
143 return false;
144}
145
146int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
147 struct list_head *list)
148{
149 unsigned int i;
150 int err = 0;
151
152 for (i = start; i < package->package.count; i++) {
153 union acpi_object *element = &package->package.elements[i];
154 struct acpi_device *rdev;
155 acpi_handle rhandle;
156
157 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
158 err = -ENODATA;
159 break;
160 }
161 rhandle = element->reference.handle;
162 if (!rhandle) {
163 err = -ENODEV;
164 break;
165 }
166
167 /* Some ACPI tables contain duplicate power resource references */
168 if (acpi_power_resource_is_dup(package, start, i))
169 continue;
170
171 rdev = acpi_add_power_resource(rhandle);
172 if (!rdev) {
173 err = -ENODEV;
174 break;
175 }
176 err = acpi_power_resources_list_add(rhandle, list);
177 if (err)
178 break;
179 }
180 if (err)
181 acpi_power_resources_list_free(list);
182
183 return err;
184}
185
186static int __get_state(acpi_handle handle, u8 *state)
187{
188 acpi_status status = AE_OK;
189 unsigned long long sta = 0;
190 u8 cur_state;
191
192 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
193 if (ACPI_FAILURE(status))
194 return -ENODEV;
195
196 cur_state = sta & ACPI_POWER_RESOURCE_STATE_ON;
197
198 acpi_handle_debug(handle, "Power resource is %s\n",
199 cur_state ? "on" : "off");
200
201 *state = cur_state;
202 return 0;
203}
204
205static int acpi_power_get_state(struct acpi_power_resource *resource, u8 *state)
206{
207 if (resource->state == ACPI_POWER_RESOURCE_STATE_UNKNOWN) {
208 int ret;
209
210 ret = __get_state(resource->device.handle, &resource->state);
211 if (ret)
212 return ret;
213 }
214
215 *state = resource->state;
216 return 0;
217}
218
219static int acpi_power_get_list_state(struct list_head *list, u8 *state)
220{
221 struct acpi_power_resource_entry *entry;
222 u8 cur_state = ACPI_POWER_RESOURCE_STATE_OFF;
223
224 if (!list || !state)
225 return -EINVAL;
226
227 /* The state of the list is 'on' IFF all resources are 'on'. */
228 list_for_each_entry(entry, list, node) {
229 struct acpi_power_resource *resource = entry->resource;
230 int result;
231
232 mutex_lock(&resource->resource_lock);
233 result = acpi_power_get_state(resource, &cur_state);
234 mutex_unlock(&resource->resource_lock);
235 if (result)
236 return result;
237
238 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
239 break;
240 }
241
242 pr_debug("Power resource list is %s\n", cur_state ? "on" : "off");
243
244 *state = cur_state;
245 return 0;
246}
247
248static int
249acpi_power_resource_add_dependent(struct acpi_power_resource *resource,
250 struct device *dev)
251{
252 struct acpi_power_dependent_device *dep;
253 int ret = 0;
254
255 mutex_lock(&resource->resource_lock);
256 list_for_each_entry(dep, &resource->dependents, node) {
257 /* Only add it once */
258 if (dep->dev == dev)
259 goto unlock;
260 }
261
262 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
263 if (!dep) {
264 ret = -ENOMEM;
265 goto unlock;
266 }
267
268 dep->dev = dev;
269 list_add_tail(&dep->node, &resource->dependents);
270 dev_dbg(dev, "added power dependency to [%s]\n",
271 resource_dev_name(resource));
272
273unlock:
274 mutex_unlock(&resource->resource_lock);
275 return ret;
276}
277
278static void
279acpi_power_resource_remove_dependent(struct acpi_power_resource *resource,
280 struct device *dev)
281{
282 struct acpi_power_dependent_device *dep;
283
284 mutex_lock(&resource->resource_lock);
285 list_for_each_entry(dep, &resource->dependents, node) {
286 if (dep->dev == dev) {
287 list_del(&dep->node);
288 kfree(dep);
289 dev_dbg(dev, "removed power dependency to [%s]\n",
290 resource_dev_name(resource));
291 break;
292 }
293 }
294 mutex_unlock(&resource->resource_lock);
295}
296
297/**
298 * acpi_device_power_add_dependent - Add dependent device of this ACPI device
299 * @adev: ACPI device pointer
300 * @dev: Dependent device
301 *
302 * If @adev has non-empty _PR0 the @dev is added as dependent device to all
303 * power resources returned by it. This means that whenever these power
304 * resources are turned _ON the dependent devices get runtime resumed. This
305 * is needed for devices such as PCI to allow its driver to re-initialize
306 * it after it went to D0uninitialized.
307 *
308 * If @adev does not have _PR0 this does nothing.
309 *
310 * Returns %0 in case of success and negative errno otherwise.
311 */
312int acpi_device_power_add_dependent(struct acpi_device *adev,
313 struct device *dev)
314{
315 struct acpi_power_resource_entry *entry;
316 struct list_head *resources;
317 int ret;
318
319 if (!adev->flags.power_manageable)
320 return 0;
321
322 resources = &adev->power.states[ACPI_STATE_D0].resources;
323 list_for_each_entry(entry, resources, node) {
324 ret = acpi_power_resource_add_dependent(entry->resource, dev);
325 if (ret)
326 goto err;
327 }
328
329 return 0;
330
331err:
332 list_for_each_entry(entry, resources, node)
333 acpi_power_resource_remove_dependent(entry->resource, dev);
334
335 return ret;
336}
337
338/**
339 * acpi_device_power_remove_dependent - Remove dependent device
340 * @adev: ACPI device pointer
341 * @dev: Dependent device
342 *
343 * Does the opposite of acpi_device_power_add_dependent() and removes the
344 * dependent device if it is found. Can be called to @adev that does not
345 * have _PR0 as well.
346 */
347void acpi_device_power_remove_dependent(struct acpi_device *adev,
348 struct device *dev)
349{
350 struct acpi_power_resource_entry *entry;
351 struct list_head *resources;
352
353 if (!adev->flags.power_manageable)
354 return;
355
356 resources = &adev->power.states[ACPI_STATE_D0].resources;
357 list_for_each_entry_reverse(entry, resources, node)
358 acpi_power_resource_remove_dependent(entry->resource, dev);
359}
360
361static int __acpi_power_on(struct acpi_power_resource *resource)
362{
363 acpi_handle handle = resource->device.handle;
364 struct acpi_power_dependent_device *dep;
365 acpi_status status = AE_OK;
366
367 status = acpi_evaluate_object(handle, "_ON", NULL, NULL);
368 if (ACPI_FAILURE(status)) {
369 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
370 return -ENODEV;
371 }
372
373 resource->state = ACPI_POWER_RESOURCE_STATE_ON;
374
375 acpi_handle_debug(handle, "Power resource turned on\n");
376
377 /*
378 * If there are other dependents on this power resource we need to
379 * resume them now so that their drivers can re-initialize the
380 * hardware properly after it went back to D0.
381 */
382 if (list_empty(&resource->dependents) ||
383 list_is_singular(&resource->dependents))
384 return 0;
385
386 list_for_each_entry(dep, &resource->dependents, node) {
387 dev_dbg(dep->dev, "runtime resuming because [%s] turned on\n",
388 resource_dev_name(resource));
389 pm_request_resume(dep->dev);
390 }
391
392 return 0;
393}
394
395static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
396{
397 int result = 0;
398
399 if (resource->ref_count++) {
400 acpi_handle_debug(resource->device.handle,
401 "Power resource already on\n");
402 } else {
403 result = __acpi_power_on(resource);
404 if (result)
405 resource->ref_count--;
406 }
407 return result;
408}
409
410static int acpi_power_on(struct acpi_power_resource *resource)
411{
412 int result;
413
414 mutex_lock(&resource->resource_lock);
415 result = acpi_power_on_unlocked(resource);
416 mutex_unlock(&resource->resource_lock);
417 return result;
418}
419
420static int __acpi_power_off(struct acpi_power_resource *resource)
421{
422 acpi_handle handle = resource->device.handle;
423 acpi_status status;
424
425 status = acpi_evaluate_object(handle, "_OFF", NULL, NULL);
426 if (ACPI_FAILURE(status)) {
427 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
428 return -ENODEV;
429 }
430
431 resource->state = ACPI_POWER_RESOURCE_STATE_OFF;
432
433 acpi_handle_debug(handle, "Power resource turned off\n");
434
435 return 0;
436}
437
438static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
439{
440 int result = 0;
441
442 if (!resource->ref_count) {
443 acpi_handle_debug(resource->device.handle,
444 "Power resource already off\n");
445 return 0;
446 }
447
448 if (--resource->ref_count) {
449 acpi_handle_debug(resource->device.handle,
450 "Power resource still in use\n");
451 } else {
452 result = __acpi_power_off(resource);
453 if (result)
454 resource->ref_count++;
455 }
456 return result;
457}
458
459static int acpi_power_off(struct acpi_power_resource *resource)
460{
461 int result;
462
463 mutex_lock(&resource->resource_lock);
464 result = acpi_power_off_unlocked(resource);
465 mutex_unlock(&resource->resource_lock);
466 return result;
467}
468
469static int acpi_power_off_list(struct list_head *list)
470{
471 struct acpi_power_resource_entry *entry;
472 int result = 0;
473
474 list_for_each_entry_reverse(entry, list, node) {
475 result = acpi_power_off(entry->resource);
476 if (result)
477 goto err;
478 }
479 return 0;
480
481 err:
482 list_for_each_entry_continue(entry, list, node)
483 acpi_power_on(entry->resource);
484
485 return result;
486}
487
488static int acpi_power_on_list(struct list_head *list)
489{
490 struct acpi_power_resource_entry *entry;
491 int result = 0;
492
493 list_for_each_entry(entry, list, node) {
494 result = acpi_power_on(entry->resource);
495 if (result)
496 goto err;
497 }
498 return 0;
499
500 err:
501 list_for_each_entry_continue_reverse(entry, list, node)
502 acpi_power_off(entry->resource);
503
504 return result;
505}
506
507static struct attribute *attrs[] = {
508 NULL,
509};
510
511static const struct attribute_group attr_groups[] = {
512 [ACPI_STATE_D0] = {
513 .name = "power_resources_D0",
514 .attrs = attrs,
515 },
516 [ACPI_STATE_D1] = {
517 .name = "power_resources_D1",
518 .attrs = attrs,
519 },
520 [ACPI_STATE_D2] = {
521 .name = "power_resources_D2",
522 .attrs = attrs,
523 },
524 [ACPI_STATE_D3_HOT] = {
525 .name = "power_resources_D3hot",
526 .attrs = attrs,
527 },
528};
529
530static const struct attribute_group wakeup_attr_group = {
531 .name = "power_resources_wakeup",
532 .attrs = attrs,
533};
534
535static void acpi_power_hide_list(struct acpi_device *adev,
536 struct list_head *resources,
537 const struct attribute_group *attr_group)
538{
539 struct acpi_power_resource_entry *entry;
540
541 if (list_empty(resources))
542 return;
543
544 list_for_each_entry_reverse(entry, resources, node) {
545 struct acpi_device *res_dev = &entry->resource->device;
546
547 sysfs_remove_link_from_group(&adev->dev.kobj,
548 attr_group->name,
549 dev_name(&res_dev->dev));
550 }
551 sysfs_remove_group(&adev->dev.kobj, attr_group);
552}
553
554static void acpi_power_expose_list(struct acpi_device *adev,
555 struct list_head *resources,
556 const struct attribute_group *attr_group)
557{
558 struct acpi_power_resource_entry *entry;
559 int ret;
560
561 if (list_empty(resources))
562 return;
563
564 ret = sysfs_create_group(&adev->dev.kobj, attr_group);
565 if (ret)
566 return;
567
568 list_for_each_entry(entry, resources, node) {
569 struct acpi_device *res_dev = &entry->resource->device;
570
571 ret = sysfs_add_link_to_group(&adev->dev.kobj,
572 attr_group->name,
573 &res_dev->dev.kobj,
574 dev_name(&res_dev->dev));
575 if (ret) {
576 acpi_power_hide_list(adev, resources, attr_group);
577 break;
578 }
579 }
580}
581
582static void acpi_power_expose_hide(struct acpi_device *adev,
583 struct list_head *resources,
584 const struct attribute_group *attr_group,
585 bool expose)
586{
587 if (expose)
588 acpi_power_expose_list(adev, resources, attr_group);
589 else
590 acpi_power_hide_list(adev, resources, attr_group);
591}
592
593void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
594{
595 int state;
596
597 if (adev->wakeup.flags.valid)
598 acpi_power_expose_hide(adev, &adev->wakeup.resources,
599 &wakeup_attr_group, add);
600
601 if (!adev->power.flags.power_resources)
602 return;
603
604 for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
605 acpi_power_expose_hide(adev,
606 &adev->power.states[state].resources,
607 &attr_groups[state], add);
608}
609
610int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
611{
612 struct acpi_power_resource_entry *entry;
613 int system_level = 5;
614
615 list_for_each_entry(entry, list, node) {
616 struct acpi_power_resource *resource = entry->resource;
617 u8 state;
618
619 mutex_lock(&resource->resource_lock);
620
621 /*
622 * Make sure that the power resource state and its reference
623 * counter value are consistent with each other.
624 */
625 if (!resource->ref_count &&
626 !acpi_power_get_state(resource, &state) &&
627 state == ACPI_POWER_RESOURCE_STATE_ON)
628 __acpi_power_off(resource);
629
630 if (system_level > resource->system_level)
631 system_level = resource->system_level;
632
633 mutex_unlock(&resource->resource_lock);
634 }
635 *system_level_p = system_level;
636 return 0;
637}
638
639/* --------------------------------------------------------------------------
640 Device Power Management
641 -------------------------------------------------------------------------- */
642
643/**
644 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
645 * ACPI 3.0) _PSW (Power State Wake)
646 * @dev: Device to handle.
647 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
648 * @sleep_state: Target sleep state of the system.
649 * @dev_state: Target power state of the device.
650 *
651 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
652 * State Wake) for the device, if present. On failure reset the device's
653 * wakeup.flags.valid flag.
654 *
655 * RETURN VALUE:
656 * 0 if either _DSW or _PSW has been successfully executed
657 * 0 if neither _DSW nor _PSW has been found
658 * -ENODEV if the execution of either _DSW or _PSW has failed
659 */
660int acpi_device_sleep_wake(struct acpi_device *dev,
661 int enable, int sleep_state, int dev_state)
662{
663 union acpi_object in_arg[3];
664 struct acpi_object_list arg_list = { 3, in_arg };
665 acpi_status status = AE_OK;
666
667 /*
668 * Try to execute _DSW first.
669 *
670 * Three arguments are needed for the _DSW object:
671 * Argument 0: enable/disable the wake capabilities
672 * Argument 1: target system state
673 * Argument 2: target device state
674 * When _DSW object is called to disable the wake capabilities, maybe
675 * the first argument is filled. The values of the other two arguments
676 * are meaningless.
677 */
678 in_arg[0].type = ACPI_TYPE_INTEGER;
679 in_arg[0].integer.value = enable;
680 in_arg[1].type = ACPI_TYPE_INTEGER;
681 in_arg[1].integer.value = sleep_state;
682 in_arg[2].type = ACPI_TYPE_INTEGER;
683 in_arg[2].integer.value = dev_state;
684 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
685 if (ACPI_SUCCESS(status)) {
686 return 0;
687 } else if (status != AE_NOT_FOUND) {
688 acpi_handle_info(dev->handle, "_DSW execution failed\n");
689 dev->wakeup.flags.valid = 0;
690 return -ENODEV;
691 }
692
693 /* Execute _PSW */
694 status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
695 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
696 acpi_handle_info(dev->handle, "_PSW execution failed\n");
697 dev->wakeup.flags.valid = 0;
698 return -ENODEV;
699 }
700
701 return 0;
702}
703
704/*
705 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
706 * 1. Power on the power resources required for the wakeup device
707 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
708 * State Wake) for the device, if present
709 */
710int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
711{
712 int err = 0;
713
714 if (!dev || !dev->wakeup.flags.valid)
715 return -EINVAL;
716
717 mutex_lock(&acpi_device_lock);
718
719 dev_dbg(&dev->dev, "Enabling wakeup power (count %d)\n",
720 dev->wakeup.prepare_count);
721
722 if (dev->wakeup.prepare_count++)
723 goto out;
724
725 err = acpi_power_on_list(&dev->wakeup.resources);
726 if (err) {
727 dev_err(&dev->dev, "Cannot turn on wakeup power resources\n");
728 dev->wakeup.flags.valid = 0;
729 goto out;
730 }
731
732 /*
733 * Passing 3 as the third argument below means the device may be
734 * put into arbitrary power state afterward.
735 */
736 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
737 if (err) {
738 acpi_power_off_list(&dev->wakeup.resources);
739 dev->wakeup.prepare_count = 0;
740 goto out;
741 }
742
743 dev_dbg(&dev->dev, "Wakeup power enabled\n");
744
745 out:
746 mutex_unlock(&acpi_device_lock);
747 return err;
748}
749
750/*
751 * Shutdown a wakeup device, counterpart of above method
752 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
753 * State Wake) for the device, if present
754 * 2. Shutdown down the power resources
755 */
756int acpi_disable_wakeup_device_power(struct acpi_device *dev)
757{
758 struct acpi_power_resource_entry *entry;
759 int err = 0;
760
761 if (!dev || !dev->wakeup.flags.valid)
762 return -EINVAL;
763
764 mutex_lock(&acpi_device_lock);
765
766 dev_dbg(&dev->dev, "Disabling wakeup power (count %d)\n",
767 dev->wakeup.prepare_count);
768
769 /* Do nothing if wakeup power has not been enabled for this device. */
770 if (dev->wakeup.prepare_count <= 0)
771 goto out;
772
773 if (--dev->wakeup.prepare_count > 0)
774 goto out;
775
776 err = acpi_device_sleep_wake(dev, 0, 0, 0);
777 if (err)
778 goto out;
779
780 /*
781 * All of the power resources in the list need to be turned off even if
782 * there are errors.
783 */
784 list_for_each_entry(entry, &dev->wakeup.resources, node) {
785 int ret;
786
787 ret = acpi_power_off(entry->resource);
788 if (ret && !err)
789 err = ret;
790 }
791 if (err) {
792 dev_err(&dev->dev, "Cannot turn off wakeup power resources\n");
793 dev->wakeup.flags.valid = 0;
794 goto out;
795 }
796
797 dev_dbg(&dev->dev, "Wakeup power disabled\n");
798
799 out:
800 mutex_unlock(&acpi_device_lock);
801 return err;
802}
803
804int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
805{
806 u8 list_state = ACPI_POWER_RESOURCE_STATE_OFF;
807 int result = 0;
808 int i = 0;
809
810 if (!device || !state)
811 return -EINVAL;
812
813 /*
814 * We know a device's inferred power state when all the resources
815 * required for a given D-state are 'on'.
816 */
817 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
818 struct list_head *list = &device->power.states[i].resources;
819
820 if (list_empty(list))
821 continue;
822
823 result = acpi_power_get_list_state(list, &list_state);
824 if (result)
825 return result;
826
827 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
828 *state = i;
829 return 0;
830 }
831 }
832
833 *state = device->power.states[ACPI_STATE_D3_COLD].flags.valid ?
834 ACPI_STATE_D3_COLD : ACPI_STATE_D3_HOT;
835 return 0;
836}
837
838int acpi_power_on_resources(struct acpi_device *device, int state)
839{
840 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
841 return -EINVAL;
842
843 return acpi_power_on_list(&device->power.states[state].resources);
844}
845
846int acpi_power_transition(struct acpi_device *device, int state)
847{
848 int result = 0;
849
850 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
851 return -EINVAL;
852
853 if (device->power.state == state || !device->flags.power_manageable)
854 return 0;
855
856 if ((device->power.state < ACPI_STATE_D0)
857 || (device->power.state > ACPI_STATE_D3_COLD))
858 return -ENODEV;
859
860 /*
861 * First we reference all power resources required in the target list
862 * (e.g. so the device doesn't lose power while transitioning). Then,
863 * we dereference all power resources used in the current list.
864 */
865 if (state < ACPI_STATE_D3_COLD)
866 result = acpi_power_on_list(
867 &device->power.states[state].resources);
868
869 if (!result && device->power.state < ACPI_STATE_D3_COLD)
870 acpi_power_off_list(
871 &device->power.states[device->power.state].resources);
872
873 /* We shouldn't change the state unless the above operations succeed. */
874 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
875
876 return result;
877}
878
879static void acpi_release_power_resource(struct device *dev)
880{
881 struct acpi_device *device = to_acpi_device(dev);
882 struct acpi_power_resource *resource;
883
884 resource = container_of(device, struct acpi_power_resource, device);
885
886 mutex_lock(&power_resource_list_lock);
887 list_del(&resource->list_node);
888 mutex_unlock(&power_resource_list_lock);
889
890 acpi_free_pnp_ids(&device->pnp);
891 kfree(resource);
892}
893
894static ssize_t resource_in_use_show(struct device *dev,
895 struct device_attribute *attr,
896 char *buf)
897{
898 struct acpi_power_resource *resource;
899
900 resource = to_power_resource(to_acpi_device(dev));
901 return sprintf(buf, "%u\n", !!resource->ref_count);
902}
903static DEVICE_ATTR_RO(resource_in_use);
904
905static void acpi_power_sysfs_remove(struct acpi_device *device)
906{
907 device_remove_file(&device->dev, &dev_attr_resource_in_use);
908}
909
910static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource)
911{
912 mutex_lock(&power_resource_list_lock);
913
914 if (!list_empty(&acpi_power_resource_list)) {
915 struct acpi_power_resource *r;
916
917 list_for_each_entry(r, &acpi_power_resource_list, list_node)
918 if (r->order > resource->order) {
919 list_add_tail(&resource->list_node, &r->list_node);
920 goto out;
921 }
922 }
923 list_add_tail(&resource->list_node, &acpi_power_resource_list);
924
925 out:
926 mutex_unlock(&power_resource_list_lock);
927}
928
929struct acpi_device *acpi_add_power_resource(acpi_handle handle)
930{
931 struct acpi_device *device = acpi_fetch_acpi_dev(handle);
932 struct acpi_power_resource *resource;
933 union acpi_object acpi_object;
934 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
935 acpi_status status;
936 u8 state_dummy;
937 int result;
938
939 if (device)
940 return device;
941
942 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
943 if (!resource)
944 return NULL;
945
946 device = &resource->device;
947 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
948 acpi_release_power_resource);
949 mutex_init(&resource->resource_lock);
950 INIT_LIST_HEAD(&resource->list_node);
951 INIT_LIST_HEAD(&resource->dependents);
952 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
953 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
954 device->power.state = ACPI_STATE_UNKNOWN;
955 device->flags.match_driver = true;
956
957 /* Evaluate the object to get the system level and resource order. */
958 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
959 if (ACPI_FAILURE(status))
960 goto err;
961
962 resource->system_level = acpi_object.power_resource.system_level;
963 resource->order = acpi_object.power_resource.resource_order;
964 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
965
966 /* Get the initial state or just flip it on if that fails. */
967 if (acpi_power_get_state(resource, &state_dummy))
968 __acpi_power_on(resource);
969
970 acpi_handle_info(handle, "New power resource\n");
971
972 result = acpi_tie_acpi_dev(device);
973 if (result)
974 goto err;
975
976 result = acpi_device_add(device);
977 if (result)
978 goto err;
979
980 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
981 device->remove = acpi_power_sysfs_remove;
982
983 acpi_power_add_resource_to_list(resource);
984 acpi_device_add_finalize(device);
985 return device;
986
987 err:
988 acpi_release_power_resource(&device->dev);
989 return NULL;
990}
991
992#ifdef CONFIG_ACPI_SLEEP
993void acpi_resume_power_resources(void)
994{
995 struct acpi_power_resource *resource;
996
997 mutex_lock(&power_resource_list_lock);
998
999 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
1000 int result;
1001 u8 state;
1002
1003 mutex_lock(&resource->resource_lock);
1004
1005 resource->state = ACPI_POWER_RESOURCE_STATE_UNKNOWN;
1006 result = acpi_power_get_state(resource, &state);
1007 if (result) {
1008 mutex_unlock(&resource->resource_lock);
1009 continue;
1010 }
1011
1012 if (state == ACPI_POWER_RESOURCE_STATE_OFF
1013 && resource->ref_count) {
1014 acpi_handle_debug(resource->device.handle, "Turning ON\n");
1015 __acpi_power_on(resource);
1016 }
1017
1018 mutex_unlock(&resource->resource_lock);
1019 }
1020
1021 mutex_unlock(&power_resource_list_lock);
1022}
1023#endif
1024
1025/**
1026 * acpi_turn_off_unused_power_resources - Turn off power resources not in use.
1027 */
1028void acpi_turn_off_unused_power_resources(void)
1029{
1030 struct acpi_power_resource *resource;
1031
1032 mutex_lock(&power_resource_list_lock);
1033
1034 list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
1035 mutex_lock(&resource->resource_lock);
1036
1037 if (!resource->ref_count &&
1038 resource->state == ACPI_POWER_RESOURCE_STATE_ON) {
1039 acpi_handle_debug(resource->device.handle, "Turning OFF\n");
1040 __acpi_power_off(resource);
1041 }
1042
1043 mutex_unlock(&resource->resource_lock);
1044 }
1045
1046 mutex_unlock(&power_resource_list_lock);
1047}