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 <linux/pm_runtime.h>
44#include <acpi/acpi_bus.h>
45#include <acpi/acpi_drivers.h>
46#include "sleep.h"
47#include "internal.h"
48
49#define PREFIX "ACPI: "
50
51#define _COMPONENT ACPI_POWER_COMPONENT
52ACPI_MODULE_NAME("power");
53#define ACPI_POWER_CLASS "power_resource"
54#define ACPI_POWER_DEVICE_NAME "Power Resource"
55#define ACPI_POWER_FILE_INFO "info"
56#define ACPI_POWER_FILE_STATUS "state"
57#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
58#define ACPI_POWER_RESOURCE_STATE_ON 0x01
59#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
60
61static int acpi_power_add(struct acpi_device *device);
62static int acpi_power_remove(struct acpi_device *device, int type);
63static int acpi_power_resume(struct acpi_device *device);
64
65static const struct acpi_device_id power_device_ids[] = {
66 {ACPI_POWER_HID, 0},
67 {"", 0},
68};
69MODULE_DEVICE_TABLE(acpi, power_device_ids);
70
71static struct acpi_driver acpi_power_driver = {
72 .name = "power",
73 .class = ACPI_POWER_CLASS,
74 .ids = power_device_ids,
75 .ops = {
76 .add = acpi_power_add,
77 .remove = acpi_power_remove,
78 .resume = acpi_power_resume,
79 },
80};
81
82/*
83 * A power managed device
84 * A device may rely on multiple power resources.
85 * */
86struct acpi_power_managed_device {
87 struct device *dev; /* The physical device */
88 acpi_handle *handle;
89};
90
91struct acpi_power_resource_device {
92 struct acpi_power_managed_device *device;
93 struct acpi_power_resource_device *next;
94};
95
96struct acpi_power_resource {
97 struct acpi_device * device;
98 acpi_bus_id name;
99 u32 system_level;
100 u32 order;
101 unsigned int ref_count;
102 struct mutex resource_lock;
103
104 /* List of devices relying on this power resource */
105 struct acpi_power_resource_device *devices;
106 struct mutex devices_lock;
107};
108
109static struct list_head acpi_power_resource_list;
110
111/* --------------------------------------------------------------------------
112 Power Resource Management
113 -------------------------------------------------------------------------- */
114
115static int
116acpi_power_get_context(acpi_handle handle,
117 struct acpi_power_resource **resource)
118{
119 int result = 0;
120 struct acpi_device *device = NULL;
121
122
123 if (!resource)
124 return -ENODEV;
125
126 result = acpi_bus_get_device(handle, &device);
127 if (result) {
128 printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle);
129 return result;
130 }
131
132 *resource = acpi_driver_data(device);
133 if (!*resource)
134 return -ENODEV;
135
136 return 0;
137}
138
139static int acpi_power_get_state(acpi_handle handle, int *state)
140{
141 acpi_status status = AE_OK;
142 unsigned long long sta = 0;
143 char node_name[5];
144 struct acpi_buffer buffer = { sizeof(node_name), node_name };
145
146
147 if (!handle || !state)
148 return -EINVAL;
149
150 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
151 if (ACPI_FAILURE(status))
152 return -ENODEV;
153
154 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
155 ACPI_POWER_RESOURCE_STATE_OFF;
156
157 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
158
159 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
160 node_name,
161 *state ? "on" : "off"));
162
163 return 0;
164}
165
166static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
167{
168 int cur_state;
169 int i = 0;
170
171 if (!list || !state)
172 return -EINVAL;
173
174 /* The state of the list is 'on' IFF all resources are 'on'. */
175
176 for (i = 0; i < list->count; i++) {
177 struct acpi_power_resource *resource;
178 acpi_handle handle = list->handles[i];
179 int result;
180
181 result = acpi_power_get_context(handle, &resource);
182 if (result)
183 return result;
184
185 mutex_lock(&resource->resource_lock);
186
187 result = acpi_power_get_state(handle, &cur_state);
188
189 mutex_unlock(&resource->resource_lock);
190
191 if (result)
192 return result;
193
194 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
195 break;
196 }
197
198 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
199 cur_state ? "on" : "off"));
200
201 *state = cur_state;
202
203 return 0;
204}
205
206/* Resume the device when all power resources in _PR0 are on */
207static void acpi_power_on_device(struct acpi_power_managed_device *device)
208{
209 struct acpi_device *acpi_dev;
210 acpi_handle handle = device->handle;
211 int state;
212
213 if (acpi_bus_get_device(handle, &acpi_dev))
214 return;
215
216 if(acpi_power_get_inferred_state(acpi_dev, &state))
217 return;
218
219 if (state == ACPI_STATE_D0 && pm_runtime_suspended(device->dev))
220 pm_request_resume(device->dev);
221}
222
223static int __acpi_power_on(struct acpi_power_resource *resource)
224{
225 acpi_status status = AE_OK;
226
227 status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
228 if (ACPI_FAILURE(status))
229 return -ENODEV;
230
231 /* Update the power resource's _device_ power state */
232 resource->device->power.state = ACPI_STATE_D0;
233
234 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
235 resource->name));
236
237 return 0;
238}
239
240static int acpi_power_on(acpi_handle handle)
241{
242 int result = 0;
243 bool resume_device = false;
244 struct acpi_power_resource *resource = NULL;
245 struct acpi_power_resource_device *device_list;
246
247 result = acpi_power_get_context(handle, &resource);
248 if (result)
249 return result;
250
251 mutex_lock(&resource->resource_lock);
252
253 if (resource->ref_count++) {
254 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
255 "Power resource [%s] already on",
256 resource->name));
257 } else {
258 result = __acpi_power_on(resource);
259 if (result)
260 resource->ref_count--;
261 else
262 resume_device = true;
263 }
264
265 mutex_unlock(&resource->resource_lock);
266
267 if (!resume_device)
268 return result;
269
270 mutex_lock(&resource->devices_lock);
271
272 device_list = resource->devices;
273 while (device_list) {
274 acpi_power_on_device(device_list->device);
275 device_list = device_list->next;
276 }
277
278 mutex_unlock(&resource->devices_lock);
279
280 return result;
281}
282
283static int acpi_power_off(acpi_handle handle)
284{
285 int result = 0;
286 acpi_status status = AE_OK;
287 struct acpi_power_resource *resource = NULL;
288
289 result = acpi_power_get_context(handle, &resource);
290 if (result)
291 return result;
292
293 mutex_lock(&resource->resource_lock);
294
295 if (!resource->ref_count) {
296 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
297 "Power resource [%s] already off",
298 resource->name));
299 goto unlock;
300 }
301
302 if (--resource->ref_count) {
303 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
304 "Power resource [%s] still in use\n",
305 resource->name));
306 goto unlock;
307 }
308
309 status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
310 if (ACPI_FAILURE(status)) {
311 result = -ENODEV;
312 } else {
313 /* Update the power resource's _device_ power state */
314 resource->device->power.state = ACPI_STATE_D3;
315
316 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
317 "Power resource [%s] turned off\n",
318 resource->name));
319 }
320
321 unlock:
322 mutex_unlock(&resource->resource_lock);
323
324 return result;
325}
326
327static void __acpi_power_off_list(struct acpi_handle_list *list, int num_res)
328{
329 int i;
330
331 for (i = num_res - 1; i >= 0 ; i--)
332 acpi_power_off(list->handles[i]);
333}
334
335static void acpi_power_off_list(struct acpi_handle_list *list)
336{
337 __acpi_power_off_list(list, list->count);
338}
339
340static int acpi_power_on_list(struct acpi_handle_list *list)
341{
342 int result = 0;
343 int i;
344
345 for (i = 0; i < list->count; i++) {
346 result = acpi_power_on(list->handles[i]);
347 if (result) {
348 __acpi_power_off_list(list, i);
349 break;
350 }
351 }
352
353 return result;
354}
355
356static void __acpi_power_resource_unregister_device(struct device *dev,
357 acpi_handle res_handle)
358{
359 struct acpi_power_resource *resource = NULL;
360 struct acpi_power_resource_device *prev, *curr;
361
362 if (acpi_power_get_context(res_handle, &resource))
363 return;
364
365 mutex_lock(&resource->devices_lock);
366 prev = NULL;
367 curr = resource->devices;
368 while (curr) {
369 if (curr->device->dev == dev) {
370 if (!prev)
371 resource->devices = curr->next;
372 else
373 prev->next = curr->next;
374
375 kfree(curr);
376 break;
377 }
378
379 prev = curr;
380 curr = curr->next;
381 }
382 mutex_unlock(&resource->devices_lock);
383}
384
385/* Unlink dev from all power resources in _PR0 */
386void acpi_power_resource_unregister_device(struct device *dev, acpi_handle handle)
387{
388 struct acpi_device *acpi_dev;
389 struct acpi_handle_list *list;
390 int i;
391
392 if (!dev || !handle)
393 return;
394
395 if (acpi_bus_get_device(handle, &acpi_dev))
396 return;
397
398 list = &acpi_dev->power.states[ACPI_STATE_D0].resources;
399
400 for (i = 0; i < list->count; i++)
401 __acpi_power_resource_unregister_device(dev,
402 list->handles[i]);
403}
404
405static int __acpi_power_resource_register_device(
406 struct acpi_power_managed_device *powered_device, acpi_handle handle)
407{
408 struct acpi_power_resource *resource = NULL;
409 struct acpi_power_resource_device *power_resource_device;
410 int result;
411
412 result = acpi_power_get_context(handle, &resource);
413 if (result)
414 return result;
415
416 power_resource_device = kzalloc(
417 sizeof(*power_resource_device), GFP_KERNEL);
418 if (!power_resource_device)
419 return -ENOMEM;
420
421 power_resource_device->device = powered_device;
422
423 mutex_lock(&resource->devices_lock);
424 power_resource_device->next = resource->devices;
425 resource->devices = power_resource_device;
426 mutex_unlock(&resource->devices_lock);
427
428 return 0;
429}
430
431/* Link dev to all power resources in _PR0 */
432int acpi_power_resource_register_device(struct device *dev, acpi_handle handle)
433{
434 struct acpi_device *acpi_dev;
435 struct acpi_handle_list *list;
436 struct acpi_power_managed_device *powered_device;
437 int i, ret;
438
439 if (!dev || !handle)
440 return -ENODEV;
441
442 ret = acpi_bus_get_device(handle, &acpi_dev);
443 if (ret)
444 goto no_power_resource;
445
446 if (!acpi_dev->power.flags.power_resources)
447 goto no_power_resource;
448
449 powered_device = kzalloc(sizeof(*powered_device), GFP_KERNEL);
450 if (!powered_device)
451 return -ENOMEM;
452
453 powered_device->dev = dev;
454 powered_device->handle = handle;
455
456 list = &acpi_dev->power.states[ACPI_STATE_D0].resources;
457
458 for (i = 0; i < list->count; i++) {
459 ret = __acpi_power_resource_register_device(powered_device,
460 list->handles[i]);
461
462 if (ret) {
463 acpi_power_resource_unregister_device(dev, handle);
464 break;
465 }
466 }
467
468 return ret;
469
470no_power_resource:
471 printk(KERN_DEBUG PREFIX "Invalid Power Resource to register!");
472 return -ENODEV;
473}
474
475/**
476 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
477 * ACPI 3.0) _PSW (Power State Wake)
478 * @dev: Device to handle.
479 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
480 * @sleep_state: Target sleep state of the system.
481 * @dev_state: Target power state of the device.
482 *
483 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
484 * State Wake) for the device, if present. On failure reset the device's
485 * wakeup.flags.valid flag.
486 *
487 * RETURN VALUE:
488 * 0 if either _DSW or _PSW has been successfully executed
489 * 0 if neither _DSW nor _PSW has been found
490 * -ENODEV if the execution of either _DSW or _PSW has failed
491 */
492int acpi_device_sleep_wake(struct acpi_device *dev,
493 int enable, int sleep_state, int dev_state)
494{
495 union acpi_object in_arg[3];
496 struct acpi_object_list arg_list = { 3, in_arg };
497 acpi_status status = AE_OK;
498
499 /*
500 * Try to execute _DSW first.
501 *
502 * Three agruments are needed for the _DSW object:
503 * Argument 0: enable/disable the wake capabilities
504 * Argument 1: target system state
505 * Argument 2: target device state
506 * When _DSW object is called to disable the wake capabilities, maybe
507 * the first argument is filled. The values of the other two agruments
508 * are meaningless.
509 */
510 in_arg[0].type = ACPI_TYPE_INTEGER;
511 in_arg[0].integer.value = enable;
512 in_arg[1].type = ACPI_TYPE_INTEGER;
513 in_arg[1].integer.value = sleep_state;
514 in_arg[2].type = ACPI_TYPE_INTEGER;
515 in_arg[2].integer.value = dev_state;
516 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
517 if (ACPI_SUCCESS(status)) {
518 return 0;
519 } else if (status != AE_NOT_FOUND) {
520 printk(KERN_ERR PREFIX "_DSW execution failed\n");
521 dev->wakeup.flags.valid = 0;
522 return -ENODEV;
523 }
524
525 /* Execute _PSW */
526 arg_list.count = 1;
527 in_arg[0].integer.value = enable;
528 status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
529 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
530 printk(KERN_ERR PREFIX "_PSW execution failed\n");
531 dev->wakeup.flags.valid = 0;
532 return -ENODEV;
533 }
534
535 return 0;
536}
537
538/*
539 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
540 * 1. Power on the power resources required for the wakeup device
541 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
542 * State Wake) for the device, if present
543 */
544int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
545{
546 int i, err = 0;
547
548 if (!dev || !dev->wakeup.flags.valid)
549 return -EINVAL;
550
551 mutex_lock(&acpi_device_lock);
552
553 if (dev->wakeup.prepare_count++)
554 goto out;
555
556 /* Open power resource */
557 for (i = 0; i < dev->wakeup.resources.count; i++) {
558 int ret = acpi_power_on(dev->wakeup.resources.handles[i]);
559 if (ret) {
560 printk(KERN_ERR PREFIX "Transition power state\n");
561 dev->wakeup.flags.valid = 0;
562 err = -ENODEV;
563 goto err_out;
564 }
565 }
566
567 /*
568 * Passing 3 as the third argument below means the device may be placed
569 * in arbitrary power state afterwards.
570 */
571 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
572
573 err_out:
574 if (err)
575 dev->wakeup.prepare_count = 0;
576
577 out:
578 mutex_unlock(&acpi_device_lock);
579 return err;
580}
581
582/*
583 * Shutdown a wakeup device, counterpart of above method
584 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
585 * State Wake) for the device, if present
586 * 2. Shutdown down the power resources
587 */
588int acpi_disable_wakeup_device_power(struct acpi_device *dev)
589{
590 int i, err = 0;
591
592 if (!dev || !dev->wakeup.flags.valid)
593 return -EINVAL;
594
595 mutex_lock(&acpi_device_lock);
596
597 if (--dev->wakeup.prepare_count > 0)
598 goto out;
599
600 /*
601 * Executing the code below even if prepare_count is already zero when
602 * the function is called may be useful, for example for initialisation.
603 */
604 if (dev->wakeup.prepare_count < 0)
605 dev->wakeup.prepare_count = 0;
606
607 err = acpi_device_sleep_wake(dev, 0, 0, 0);
608 if (err)
609 goto out;
610
611 /* Close power resource */
612 for (i = 0; i < dev->wakeup.resources.count; i++) {
613 int ret = acpi_power_off(dev->wakeup.resources.handles[i]);
614 if (ret) {
615 printk(KERN_ERR PREFIX "Transition power state\n");
616 dev->wakeup.flags.valid = 0;
617 err = -ENODEV;
618 goto out;
619 }
620 }
621
622 out:
623 mutex_unlock(&acpi_device_lock);
624 return err;
625}
626
627/* --------------------------------------------------------------------------
628 Device Power Management
629 -------------------------------------------------------------------------- */
630
631int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
632{
633 int result = 0;
634 struct acpi_handle_list *list = NULL;
635 int list_state = 0;
636 int i = 0;
637
638 if (!device || !state)
639 return -EINVAL;
640
641 /*
642 * We know a device's inferred power state when all the resources
643 * required for a given D-state are 'on'.
644 */
645 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
646 list = &device->power.states[i].resources;
647 if (list->count < 1)
648 continue;
649
650 result = acpi_power_get_list_state(list, &list_state);
651 if (result)
652 return result;
653
654 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
655 *state = i;
656 return 0;
657 }
658 }
659
660 *state = ACPI_STATE_D3;
661 return 0;
662}
663
664int acpi_power_on_resources(struct acpi_device *device, int state)
665{
666 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3)
667 return -EINVAL;
668
669 return acpi_power_on_list(&device->power.states[state].resources);
670}
671
672int acpi_power_transition(struct acpi_device *device, int state)
673{
674 int result = 0;
675
676 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
677 return -EINVAL;
678
679 if (device->power.state == state)
680 return 0;
681
682 if ((device->power.state < ACPI_STATE_D0)
683 || (device->power.state > ACPI_STATE_D3_COLD))
684 return -ENODEV;
685
686 /* TBD: Resources must be ordered. */
687
688 /*
689 * First we reference all power resources required in the target list
690 * (e.g. so the device doesn't lose power while transitioning). Then,
691 * we dereference all power resources used in the current list.
692 */
693 if (state < ACPI_STATE_D3_COLD)
694 result = acpi_power_on_list(
695 &device->power.states[state].resources);
696
697 if (!result && device->power.state < ACPI_STATE_D3_COLD)
698 acpi_power_off_list(
699 &device->power.states[device->power.state].resources);
700
701 /* We shouldn't change the state unless the above operations succeed. */
702 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
703
704 return result;
705}
706
707/* --------------------------------------------------------------------------
708 Driver Interface
709 -------------------------------------------------------------------------- */
710
711static int acpi_power_add(struct acpi_device *device)
712{
713 int result = 0, state;
714 acpi_status status = AE_OK;
715 struct acpi_power_resource *resource = NULL;
716 union acpi_object acpi_object;
717 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
718
719
720 if (!device)
721 return -EINVAL;
722
723 resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
724 if (!resource)
725 return -ENOMEM;
726
727 resource->device = device;
728 mutex_init(&resource->resource_lock);
729 mutex_init(&resource->devices_lock);
730 strcpy(resource->name, device->pnp.bus_id);
731 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
732 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
733 device->driver_data = resource;
734
735 /* Evalute the object to get the system level and resource order. */
736 status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer);
737 if (ACPI_FAILURE(status)) {
738 result = -ENODEV;
739 goto end;
740 }
741 resource->system_level = acpi_object.power_resource.system_level;
742 resource->order = acpi_object.power_resource.resource_order;
743
744 result = acpi_power_get_state(device->handle, &state);
745 if (result)
746 goto end;
747
748 switch (state) {
749 case ACPI_POWER_RESOURCE_STATE_ON:
750 device->power.state = ACPI_STATE_D0;
751 break;
752 case ACPI_POWER_RESOURCE_STATE_OFF:
753 device->power.state = ACPI_STATE_D3;
754 break;
755 default:
756 device->power.state = ACPI_STATE_UNKNOWN;
757 break;
758 }
759
760 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
761 acpi_device_bid(device), state ? "on" : "off");
762
763 end:
764 if (result)
765 kfree(resource);
766
767 return result;
768}
769
770static int acpi_power_remove(struct acpi_device *device, int type)
771{
772 struct acpi_power_resource *resource;
773
774 if (!device)
775 return -EINVAL;
776
777 resource = acpi_driver_data(device);
778 if (!resource)
779 return -EINVAL;
780
781 kfree(resource);
782
783 return 0;
784}
785
786static int acpi_power_resume(struct acpi_device *device)
787{
788 int result = 0, state;
789 struct acpi_power_resource *resource;
790
791 if (!device)
792 return -EINVAL;
793
794 resource = acpi_driver_data(device);
795 if (!resource)
796 return -EINVAL;
797
798 mutex_lock(&resource->resource_lock);
799
800 result = acpi_power_get_state(device->handle, &state);
801 if (result)
802 goto unlock;
803
804 if (state == ACPI_POWER_RESOURCE_STATE_OFF && resource->ref_count)
805 result = __acpi_power_on(resource);
806
807 unlock:
808 mutex_unlock(&resource->resource_lock);
809
810 return result;
811}
812
813int __init acpi_power_init(void)
814{
815 INIT_LIST_HEAD(&acpi_power_resource_list);
816 return acpi_bus_register_driver(&acpi_power_driver);
817}
1/*
2 * drivers/acpi/power.c - ACPI Power Resources management.
3 *
4 * Copyright (C) 2001 - 2015 Intel Corp.
5 * Author: Andy Grover <andrew.grover@intel.com>
6 * Author: Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8 *
9 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or (at
14 * your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful, but
17 * WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
20 *
21 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
22 */
23
24/*
25 * ACPI power-managed devices may be controlled in two ways:
26 * 1. via "Device Specific (D-State) Control"
27 * 2. via "Power Resource Control".
28 * The code below deals with ACPI Power Resources control.
29 *
30 * An ACPI "power resource object" represents a software controllable power
31 * plane, clock plane, or other resource depended on by a device.
32 *
33 * A device may rely on multiple power resources, and a power resource
34 * may be shared by multiple devices.
35 */
36
37#include <linux/kernel.h>
38#include <linux/module.h>
39#include <linux/init.h>
40#include <linux/types.h>
41#include <linux/slab.h>
42#include <linux/pm_runtime.h>
43#include <linux/sysfs.h>
44#include <linux/acpi.h>
45#include "sleep.h"
46#include "internal.h"
47
48#define _COMPONENT ACPI_POWER_COMPONENT
49ACPI_MODULE_NAME("power");
50#define ACPI_POWER_CLASS "power_resource"
51#define ACPI_POWER_DEVICE_NAME "Power Resource"
52#define ACPI_POWER_FILE_INFO "info"
53#define ACPI_POWER_FILE_STATUS "state"
54#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
55#define ACPI_POWER_RESOURCE_STATE_ON 0x01
56#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
57
58struct acpi_power_resource {
59 struct acpi_device device;
60 struct list_head list_node;
61 char *name;
62 u32 system_level;
63 u32 order;
64 unsigned int ref_count;
65 bool wakeup_enabled;
66 struct mutex resource_lock;
67};
68
69struct acpi_power_resource_entry {
70 struct list_head node;
71 struct acpi_power_resource *resource;
72};
73
74static LIST_HEAD(acpi_power_resource_list);
75static DEFINE_MUTEX(power_resource_list_lock);
76
77/* --------------------------------------------------------------------------
78 Power Resource Management
79 -------------------------------------------------------------------------- */
80
81static inline
82struct acpi_power_resource *to_power_resource(struct acpi_device *device)
83{
84 return container_of(device, struct acpi_power_resource, device);
85}
86
87static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
88{
89 struct acpi_device *device;
90
91 if (acpi_bus_get_device(handle, &device))
92 return NULL;
93
94 return to_power_resource(device);
95}
96
97static int acpi_power_resources_list_add(acpi_handle handle,
98 struct list_head *list)
99{
100 struct acpi_power_resource *resource = acpi_power_get_context(handle);
101 struct acpi_power_resource_entry *entry;
102
103 if (!resource || !list)
104 return -EINVAL;
105
106 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
107 if (!entry)
108 return -ENOMEM;
109
110 entry->resource = resource;
111 if (!list_empty(list)) {
112 struct acpi_power_resource_entry *e;
113
114 list_for_each_entry(e, list, node)
115 if (e->resource->order > resource->order) {
116 list_add_tail(&entry->node, &e->node);
117 return 0;
118 }
119 }
120 list_add_tail(&entry->node, list);
121 return 0;
122}
123
124void acpi_power_resources_list_free(struct list_head *list)
125{
126 struct acpi_power_resource_entry *entry, *e;
127
128 list_for_each_entry_safe(entry, e, list, node) {
129 list_del(&entry->node);
130 kfree(entry);
131 }
132}
133
134int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
135 struct list_head *list)
136{
137 unsigned int i;
138 int err = 0;
139
140 for (i = start; i < package->package.count; i++) {
141 union acpi_object *element = &package->package.elements[i];
142 acpi_handle rhandle;
143
144 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
145 err = -ENODATA;
146 break;
147 }
148 rhandle = element->reference.handle;
149 if (!rhandle) {
150 err = -ENODEV;
151 break;
152 }
153 err = acpi_add_power_resource(rhandle);
154 if (err)
155 break;
156
157 err = acpi_power_resources_list_add(rhandle, list);
158 if (err)
159 break;
160 }
161 if (err)
162 acpi_power_resources_list_free(list);
163
164 return err;
165}
166
167static int acpi_power_get_state(acpi_handle handle, int *state)
168{
169 acpi_status status = AE_OK;
170 unsigned long long sta = 0;
171 char node_name[5];
172 struct acpi_buffer buffer = { sizeof(node_name), node_name };
173
174
175 if (!handle || !state)
176 return -EINVAL;
177
178 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
179 if (ACPI_FAILURE(status))
180 return -ENODEV;
181
182 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
183 ACPI_POWER_RESOURCE_STATE_OFF;
184
185 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
186
187 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
188 node_name,
189 *state ? "on" : "off"));
190
191 return 0;
192}
193
194static int acpi_power_get_list_state(struct list_head *list, int *state)
195{
196 struct acpi_power_resource_entry *entry;
197 int cur_state;
198
199 if (!list || !state)
200 return -EINVAL;
201
202 /* The state of the list is 'on' IFF all resources are 'on'. */
203 cur_state = 0;
204 list_for_each_entry(entry, list, node) {
205 struct acpi_power_resource *resource = entry->resource;
206 acpi_handle handle = resource->device.handle;
207 int result;
208
209 mutex_lock(&resource->resource_lock);
210 result = acpi_power_get_state(handle, &cur_state);
211 mutex_unlock(&resource->resource_lock);
212 if (result)
213 return result;
214
215 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
216 break;
217 }
218
219 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
220 cur_state ? "on" : "off"));
221
222 *state = cur_state;
223 return 0;
224}
225
226static int __acpi_power_on(struct acpi_power_resource *resource)
227{
228 acpi_status status = AE_OK;
229
230 status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL);
231 if (ACPI_FAILURE(status))
232 return -ENODEV;
233
234 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
235 resource->name));
236
237 return 0;
238}
239
240static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
241{
242 int result = 0;
243
244 if (resource->ref_count++) {
245 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
246 "Power resource [%s] already on\n",
247 resource->name));
248 } else {
249 result = __acpi_power_on(resource);
250 if (result)
251 resource->ref_count--;
252 }
253 return result;
254}
255
256static int acpi_power_on(struct acpi_power_resource *resource)
257{
258 int result;
259
260 mutex_lock(&resource->resource_lock);
261 result = acpi_power_on_unlocked(resource);
262 mutex_unlock(&resource->resource_lock);
263 return result;
264}
265
266static int __acpi_power_off(struct acpi_power_resource *resource)
267{
268 acpi_status status;
269
270 status = acpi_evaluate_object(resource->device.handle, "_OFF",
271 NULL, NULL);
272 if (ACPI_FAILURE(status))
273 return -ENODEV;
274
275 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned off\n",
276 resource->name));
277 return 0;
278}
279
280static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
281{
282 int result = 0;
283
284 if (!resource->ref_count) {
285 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
286 "Power resource [%s] already off\n",
287 resource->name));
288 return 0;
289 }
290
291 if (--resource->ref_count) {
292 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
293 "Power resource [%s] still in use\n",
294 resource->name));
295 } else {
296 result = __acpi_power_off(resource);
297 if (result)
298 resource->ref_count++;
299 }
300 return result;
301}
302
303static int acpi_power_off(struct acpi_power_resource *resource)
304{
305 int result;
306
307 mutex_lock(&resource->resource_lock);
308 result = acpi_power_off_unlocked(resource);
309 mutex_unlock(&resource->resource_lock);
310 return result;
311}
312
313static int acpi_power_off_list(struct list_head *list)
314{
315 struct acpi_power_resource_entry *entry;
316 int result = 0;
317
318 list_for_each_entry_reverse(entry, list, node) {
319 result = acpi_power_off(entry->resource);
320 if (result)
321 goto err;
322 }
323 return 0;
324
325 err:
326 list_for_each_entry_continue(entry, list, node)
327 acpi_power_on(entry->resource);
328
329 return result;
330}
331
332static int acpi_power_on_list(struct list_head *list)
333{
334 struct acpi_power_resource_entry *entry;
335 int result = 0;
336
337 list_for_each_entry(entry, list, node) {
338 result = acpi_power_on(entry->resource);
339 if (result)
340 goto err;
341 }
342 return 0;
343
344 err:
345 list_for_each_entry_continue_reverse(entry, list, node)
346 acpi_power_off(entry->resource);
347
348 return result;
349}
350
351static struct attribute *attrs[] = {
352 NULL,
353};
354
355static const struct attribute_group attr_groups[] = {
356 [ACPI_STATE_D0] = {
357 .name = "power_resources_D0",
358 .attrs = attrs,
359 },
360 [ACPI_STATE_D1] = {
361 .name = "power_resources_D1",
362 .attrs = attrs,
363 },
364 [ACPI_STATE_D2] = {
365 .name = "power_resources_D2",
366 .attrs = attrs,
367 },
368 [ACPI_STATE_D3_HOT] = {
369 .name = "power_resources_D3hot",
370 .attrs = attrs,
371 },
372};
373
374static const struct attribute_group wakeup_attr_group = {
375 .name = "power_resources_wakeup",
376 .attrs = attrs,
377};
378
379static void acpi_power_hide_list(struct acpi_device *adev,
380 struct list_head *resources,
381 const struct attribute_group *attr_group)
382{
383 struct acpi_power_resource_entry *entry;
384
385 if (list_empty(resources))
386 return;
387
388 list_for_each_entry_reverse(entry, resources, node) {
389 struct acpi_device *res_dev = &entry->resource->device;
390
391 sysfs_remove_link_from_group(&adev->dev.kobj,
392 attr_group->name,
393 dev_name(&res_dev->dev));
394 }
395 sysfs_remove_group(&adev->dev.kobj, attr_group);
396}
397
398static void acpi_power_expose_list(struct acpi_device *adev,
399 struct list_head *resources,
400 const struct attribute_group *attr_group)
401{
402 struct acpi_power_resource_entry *entry;
403 int ret;
404
405 if (list_empty(resources))
406 return;
407
408 ret = sysfs_create_group(&adev->dev.kobj, attr_group);
409 if (ret)
410 return;
411
412 list_for_each_entry(entry, resources, node) {
413 struct acpi_device *res_dev = &entry->resource->device;
414
415 ret = sysfs_add_link_to_group(&adev->dev.kobj,
416 attr_group->name,
417 &res_dev->dev.kobj,
418 dev_name(&res_dev->dev));
419 if (ret) {
420 acpi_power_hide_list(adev, resources, attr_group);
421 break;
422 }
423 }
424}
425
426static void acpi_power_expose_hide(struct acpi_device *adev,
427 struct list_head *resources,
428 const struct attribute_group *attr_group,
429 bool expose)
430{
431 if (expose)
432 acpi_power_expose_list(adev, resources, attr_group);
433 else
434 acpi_power_hide_list(adev, resources, attr_group);
435}
436
437void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
438{
439 int state;
440
441 if (adev->wakeup.flags.valid)
442 acpi_power_expose_hide(adev, &adev->wakeup.resources,
443 &wakeup_attr_group, add);
444
445 if (!adev->power.flags.power_resources)
446 return;
447
448 for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
449 acpi_power_expose_hide(adev,
450 &adev->power.states[state].resources,
451 &attr_groups[state], add);
452}
453
454int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
455{
456 struct acpi_power_resource_entry *entry;
457 int system_level = 5;
458
459 list_for_each_entry(entry, list, node) {
460 struct acpi_power_resource *resource = entry->resource;
461 acpi_handle handle = resource->device.handle;
462 int result;
463 int state;
464
465 mutex_lock(&resource->resource_lock);
466
467 result = acpi_power_get_state(handle, &state);
468 if (result) {
469 mutex_unlock(&resource->resource_lock);
470 return result;
471 }
472 if (state == ACPI_POWER_RESOURCE_STATE_ON) {
473 resource->ref_count++;
474 resource->wakeup_enabled = true;
475 }
476 if (system_level > resource->system_level)
477 system_level = resource->system_level;
478
479 mutex_unlock(&resource->resource_lock);
480 }
481 *system_level_p = system_level;
482 return 0;
483}
484
485/* --------------------------------------------------------------------------
486 Device Power Management
487 -------------------------------------------------------------------------- */
488
489/**
490 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
491 * ACPI 3.0) _PSW (Power State Wake)
492 * @dev: Device to handle.
493 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
494 * @sleep_state: Target sleep state of the system.
495 * @dev_state: Target power state of the device.
496 *
497 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
498 * State Wake) for the device, if present. On failure reset the device's
499 * wakeup.flags.valid flag.
500 *
501 * RETURN VALUE:
502 * 0 if either _DSW or _PSW has been successfully executed
503 * 0 if neither _DSW nor _PSW has been found
504 * -ENODEV if the execution of either _DSW or _PSW has failed
505 */
506int acpi_device_sleep_wake(struct acpi_device *dev,
507 int enable, int sleep_state, int dev_state)
508{
509 union acpi_object in_arg[3];
510 struct acpi_object_list arg_list = { 3, in_arg };
511 acpi_status status = AE_OK;
512
513 /*
514 * Try to execute _DSW first.
515 *
516 * Three agruments are needed for the _DSW object:
517 * Argument 0: enable/disable the wake capabilities
518 * Argument 1: target system state
519 * Argument 2: target device state
520 * When _DSW object is called to disable the wake capabilities, maybe
521 * the first argument is filled. The values of the other two agruments
522 * are meaningless.
523 */
524 in_arg[0].type = ACPI_TYPE_INTEGER;
525 in_arg[0].integer.value = enable;
526 in_arg[1].type = ACPI_TYPE_INTEGER;
527 in_arg[1].integer.value = sleep_state;
528 in_arg[2].type = ACPI_TYPE_INTEGER;
529 in_arg[2].integer.value = dev_state;
530 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
531 if (ACPI_SUCCESS(status)) {
532 return 0;
533 } else if (status != AE_NOT_FOUND) {
534 printk(KERN_ERR PREFIX "_DSW execution failed\n");
535 dev->wakeup.flags.valid = 0;
536 return -ENODEV;
537 }
538
539 /* Execute _PSW */
540 status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
541 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
542 printk(KERN_ERR PREFIX "_PSW execution failed\n");
543 dev->wakeup.flags.valid = 0;
544 return -ENODEV;
545 }
546
547 return 0;
548}
549
550/*
551 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
552 * 1. Power on the power resources required for the wakeup device
553 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
554 * State Wake) for the device, if present
555 */
556int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
557{
558 struct acpi_power_resource_entry *entry;
559 int err = 0;
560
561 if (!dev || !dev->wakeup.flags.valid)
562 return -EINVAL;
563
564 mutex_lock(&acpi_device_lock);
565
566 if (dev->wakeup.prepare_count++)
567 goto out;
568
569 list_for_each_entry(entry, &dev->wakeup.resources, node) {
570 struct acpi_power_resource *resource = entry->resource;
571
572 mutex_lock(&resource->resource_lock);
573
574 if (!resource->wakeup_enabled) {
575 err = acpi_power_on_unlocked(resource);
576 if (!err)
577 resource->wakeup_enabled = true;
578 }
579
580 mutex_unlock(&resource->resource_lock);
581
582 if (err) {
583 dev_err(&dev->dev,
584 "Cannot turn wakeup power resources on\n");
585 dev->wakeup.flags.valid = 0;
586 goto out;
587 }
588 }
589 /*
590 * Passing 3 as the third argument below means the device may be
591 * put into arbitrary power state afterward.
592 */
593 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
594 if (err)
595 dev->wakeup.prepare_count = 0;
596
597 out:
598 mutex_unlock(&acpi_device_lock);
599 return err;
600}
601
602/*
603 * Shutdown a wakeup device, counterpart of above method
604 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
605 * State Wake) for the device, if present
606 * 2. Shutdown down the power resources
607 */
608int acpi_disable_wakeup_device_power(struct acpi_device *dev)
609{
610 struct acpi_power_resource_entry *entry;
611 int err = 0;
612
613 if (!dev || !dev->wakeup.flags.valid)
614 return -EINVAL;
615
616 mutex_lock(&acpi_device_lock);
617
618 if (--dev->wakeup.prepare_count > 0)
619 goto out;
620
621 /*
622 * Executing the code below even if prepare_count is already zero when
623 * the function is called may be useful, for example for initialisation.
624 */
625 if (dev->wakeup.prepare_count < 0)
626 dev->wakeup.prepare_count = 0;
627
628 err = acpi_device_sleep_wake(dev, 0, 0, 0);
629 if (err)
630 goto out;
631
632 list_for_each_entry(entry, &dev->wakeup.resources, node) {
633 struct acpi_power_resource *resource = entry->resource;
634
635 mutex_lock(&resource->resource_lock);
636
637 if (resource->wakeup_enabled) {
638 err = acpi_power_off_unlocked(resource);
639 if (!err)
640 resource->wakeup_enabled = false;
641 }
642
643 mutex_unlock(&resource->resource_lock);
644
645 if (err) {
646 dev_err(&dev->dev,
647 "Cannot turn wakeup power resources off\n");
648 dev->wakeup.flags.valid = 0;
649 break;
650 }
651 }
652
653 out:
654 mutex_unlock(&acpi_device_lock);
655 return err;
656}
657
658int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
659{
660 int result = 0;
661 int list_state = 0;
662 int i = 0;
663
664 if (!device || !state)
665 return -EINVAL;
666
667 /*
668 * We know a device's inferred power state when all the resources
669 * required for a given D-state are 'on'.
670 */
671 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
672 struct list_head *list = &device->power.states[i].resources;
673
674 if (list_empty(list))
675 continue;
676
677 result = acpi_power_get_list_state(list, &list_state);
678 if (result)
679 return result;
680
681 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
682 *state = i;
683 return 0;
684 }
685 }
686
687 *state = device->power.states[ACPI_STATE_D3_COLD].flags.valid ?
688 ACPI_STATE_D3_COLD : ACPI_STATE_D3_HOT;
689 return 0;
690}
691
692int acpi_power_on_resources(struct acpi_device *device, int state)
693{
694 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
695 return -EINVAL;
696
697 return acpi_power_on_list(&device->power.states[state].resources);
698}
699
700int acpi_power_transition(struct acpi_device *device, int state)
701{
702 int result = 0;
703
704 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
705 return -EINVAL;
706
707 if (device->power.state == state || !device->flags.power_manageable)
708 return 0;
709
710 if ((device->power.state < ACPI_STATE_D0)
711 || (device->power.state > ACPI_STATE_D3_COLD))
712 return -ENODEV;
713
714 /*
715 * First we reference all power resources required in the target list
716 * (e.g. so the device doesn't lose power while transitioning). Then,
717 * we dereference all power resources used in the current list.
718 */
719 if (state < ACPI_STATE_D3_COLD)
720 result = acpi_power_on_list(
721 &device->power.states[state].resources);
722
723 if (!result && device->power.state < ACPI_STATE_D3_COLD)
724 acpi_power_off_list(
725 &device->power.states[device->power.state].resources);
726
727 /* We shouldn't change the state unless the above operations succeed. */
728 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
729
730 return result;
731}
732
733static void acpi_release_power_resource(struct device *dev)
734{
735 struct acpi_device *device = to_acpi_device(dev);
736 struct acpi_power_resource *resource;
737
738 resource = container_of(device, struct acpi_power_resource, device);
739
740 mutex_lock(&power_resource_list_lock);
741 list_del(&resource->list_node);
742 mutex_unlock(&power_resource_list_lock);
743
744 acpi_free_pnp_ids(&device->pnp);
745 kfree(resource);
746}
747
748static ssize_t acpi_power_in_use_show(struct device *dev,
749 struct device_attribute *attr,
750 char *buf) {
751 struct acpi_power_resource *resource;
752
753 resource = to_power_resource(to_acpi_device(dev));
754 return sprintf(buf, "%u\n", !!resource->ref_count);
755}
756static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
757
758static void acpi_power_sysfs_remove(struct acpi_device *device)
759{
760 device_remove_file(&device->dev, &dev_attr_resource_in_use);
761}
762
763static void acpi_power_add_resource_to_list(struct acpi_power_resource *resource)
764{
765 mutex_lock(&power_resource_list_lock);
766
767 if (!list_empty(&acpi_power_resource_list)) {
768 struct acpi_power_resource *r;
769
770 list_for_each_entry(r, &acpi_power_resource_list, list_node)
771 if (r->order > resource->order) {
772 list_add_tail(&resource->list_node, &r->list_node);
773 goto out;
774 }
775 }
776 list_add_tail(&resource->list_node, &acpi_power_resource_list);
777
778 out:
779 mutex_unlock(&power_resource_list_lock);
780}
781
782int acpi_add_power_resource(acpi_handle handle)
783{
784 struct acpi_power_resource *resource;
785 struct acpi_device *device = NULL;
786 union acpi_object acpi_object;
787 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
788 acpi_status status;
789 int state, result = -ENODEV;
790
791 acpi_bus_get_device(handle, &device);
792 if (device)
793 return 0;
794
795 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
796 if (!resource)
797 return -ENOMEM;
798
799 device = &resource->device;
800 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
801 ACPI_STA_DEFAULT);
802 mutex_init(&resource->resource_lock);
803 INIT_LIST_HEAD(&resource->list_node);
804 resource->name = device->pnp.bus_id;
805 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
806 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
807 device->power.state = ACPI_STATE_UNKNOWN;
808
809 /* Evalute the object to get the system level and resource order. */
810 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
811 if (ACPI_FAILURE(status))
812 goto err;
813
814 resource->system_level = acpi_object.power_resource.system_level;
815 resource->order = acpi_object.power_resource.resource_order;
816
817 result = acpi_power_get_state(handle, &state);
818 if (result)
819 goto err;
820
821 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
822 acpi_device_bid(device), state ? "on" : "off");
823
824 device->flags.match_driver = true;
825 result = acpi_device_add(device, acpi_release_power_resource);
826 if (result)
827 goto err;
828
829 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
830 device->remove = acpi_power_sysfs_remove;
831
832 acpi_power_add_resource_to_list(resource);
833 acpi_device_add_finalize(device);
834 return 0;
835
836 err:
837 acpi_release_power_resource(&device->dev);
838 return result;
839}
840
841#ifdef CONFIG_ACPI_SLEEP
842void acpi_resume_power_resources(void)
843{
844 struct acpi_power_resource *resource;
845
846 mutex_lock(&power_resource_list_lock);
847
848 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
849 int result, state;
850
851 mutex_lock(&resource->resource_lock);
852
853 result = acpi_power_get_state(resource->device.handle, &state);
854 if (result) {
855 mutex_unlock(&resource->resource_lock);
856 continue;
857 }
858
859 if (state == ACPI_POWER_RESOURCE_STATE_OFF
860 && resource->ref_count) {
861 dev_info(&resource->device.dev, "Turning ON\n");
862 __acpi_power_on(resource);
863 }
864
865 mutex_unlock(&resource->resource_lock);
866 }
867
868 mutex_unlock(&power_resource_list_lock);
869}
870
871void acpi_turn_off_unused_power_resources(void)
872{
873 struct acpi_power_resource *resource;
874
875 mutex_lock(&power_resource_list_lock);
876
877 list_for_each_entry_reverse(resource, &acpi_power_resource_list, list_node) {
878 int result, state;
879
880 mutex_lock(&resource->resource_lock);
881
882 result = acpi_power_get_state(resource->device.handle, &state);
883 if (result) {
884 mutex_unlock(&resource->resource_lock);
885 continue;
886 }
887
888 if (state == ACPI_POWER_RESOURCE_STATE_ON
889 && !resource->ref_count) {
890 dev_info(&resource->device.dev, "Turning OFF\n");
891 __acpi_power_off(resource);
892 }
893
894 mutex_unlock(&resource->resource_lock);
895 }
896
897 mutex_unlock(&power_resource_list_lock);
898}
899#endif