Loading...
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/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 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
954 strcpy(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}