2 * acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
38 #include <linux/kernel.h>
39 #include <linux/module.h>
40 #include <linux/init.h>
41 #include <linux/types.h>
42 #include <linux/slab.h>
43 #include <linux/pm_runtime.h>
44 #include <linux/sysfs.h>
45 #include <acpi/acpi_bus.h>
46 #include <acpi/acpi_drivers.h>
50 #define PREFIX "ACPI: "
52 #define _COMPONENT ACPI_POWER_COMPONENT
53 ACPI_MODULE_NAME("power");
54 #define ACPI_POWER_CLASS "power_resource"
55 #define ACPI_POWER_DEVICE_NAME "Power Resource"
56 #define ACPI_POWER_FILE_INFO "info"
57 #define ACPI_POWER_FILE_STATUS "state"
58 #define ACPI_POWER_RESOURCE_STATE_OFF 0x00
59 #define ACPI_POWER_RESOURCE_STATE_ON 0x01
60 #define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
62 struct acpi_power_resource
{
63 struct acpi_device device
;
64 struct list_head list_node
;
68 unsigned int ref_count
;
70 struct mutex resource_lock
;
73 struct acpi_power_resource_entry
{
74 struct list_head node
;
75 struct acpi_power_resource
*resource
;
78 static LIST_HEAD(acpi_power_resource_list
);
79 static DEFINE_MUTEX(power_resource_list_lock
);
81 /* --------------------------------------------------------------------------
82 Power Resource Management
83 -------------------------------------------------------------------------- */
86 struct acpi_power_resource
*to_power_resource(struct acpi_device
*device
)
88 return container_of(device
, struct acpi_power_resource
, device
);
91 static struct acpi_power_resource
*acpi_power_get_context(acpi_handle handle
)
93 struct acpi_device
*device
;
95 if (acpi_bus_get_device(handle
, &device
))
98 return to_power_resource(device
);
101 static int acpi_power_resources_list_add(acpi_handle handle
,
102 struct list_head
*list
)
104 struct acpi_power_resource
*resource
= acpi_power_get_context(handle
);
105 struct acpi_power_resource_entry
*entry
;
107 if (!resource
|| !list
)
110 entry
= kzalloc(sizeof(*entry
), GFP_KERNEL
);
114 entry
->resource
= resource
;
115 if (!list_empty(list
)) {
116 struct acpi_power_resource_entry
*e
;
118 list_for_each_entry(e
, list
, node
)
119 if (e
->resource
->order
> resource
->order
) {
120 list_add_tail(&entry
->node
, &e
->node
);
124 list_add_tail(&entry
->node
, list
);
128 void acpi_power_resources_list_free(struct list_head
*list
)
130 struct acpi_power_resource_entry
*entry
, *e
;
132 list_for_each_entry_safe(entry
, e
, list
, node
) {
133 list_del(&entry
->node
);
138 int acpi_extract_power_resources(union acpi_object
*package
, unsigned int start
,
139 struct list_head
*list
)
144 for (i
= start
; i
< package
->package
.count
; i
++) {
145 union acpi_object
*element
= &package
->package
.elements
[i
];
148 if (element
->type
!= ACPI_TYPE_LOCAL_REFERENCE
) {
152 rhandle
= element
->reference
.handle
;
157 err
= acpi_add_power_resource(rhandle
);
161 err
= acpi_power_resources_list_add(rhandle
, list
);
166 acpi_power_resources_list_free(list
);
171 static int acpi_power_get_state(acpi_handle handle
, int *state
)
173 acpi_status status
= AE_OK
;
174 unsigned long long sta
= 0;
176 struct acpi_buffer buffer
= { sizeof(node_name
), node_name
};
179 if (!handle
|| !state
)
182 status
= acpi_evaluate_integer(handle
, "_STA", NULL
, &sta
);
183 if (ACPI_FAILURE(status
))
186 *state
= (sta
& 0x01)?ACPI_POWER_RESOURCE_STATE_ON
:
187 ACPI_POWER_RESOURCE_STATE_OFF
;
189 acpi_get_name(handle
, ACPI_SINGLE_NAME
, &buffer
);
191 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] is %s\n",
193 *state
? "on" : "off"));
198 static int acpi_power_get_list_state(struct list_head
*list
, int *state
)
200 struct acpi_power_resource_entry
*entry
;
206 /* The state of the list is 'on' IFF all resources are 'on'. */
207 list_for_each_entry(entry
, list
, node
) {
208 struct acpi_power_resource
*resource
= entry
->resource
;
209 acpi_handle handle
= resource
->device
.handle
;
212 mutex_lock(&resource
->resource_lock
);
213 result
= acpi_power_get_state(handle
, &cur_state
);
214 mutex_unlock(&resource
->resource_lock
);
218 if (cur_state
!= ACPI_POWER_RESOURCE_STATE_ON
)
222 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource list is %s\n",
223 cur_state
? "on" : "off"));
229 static int __acpi_power_on(struct acpi_power_resource
*resource
)
231 acpi_status status
= AE_OK
;
233 status
= acpi_evaluate_object(resource
->device
.handle
, "_ON", NULL
, NULL
);
234 if (ACPI_FAILURE(status
))
237 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Power resource [%s] turned on\n",
243 static int acpi_power_on_unlocked(struct acpi_power_resource
*resource
)
247 if (resource
->ref_count
++) {
248 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
249 "Power resource [%s] already on\n",
252 result
= __acpi_power_on(resource
);
254 resource
->ref_count
--;
259 static int acpi_power_on(struct acpi_power_resource
*resource
)
263 mutex_lock(&resource
->resource_lock
);
264 result
= acpi_power_on_unlocked(resource
);
265 mutex_unlock(&resource
->resource_lock
);
269 static int __acpi_power_off(struct acpi_power_resource
*resource
)
273 status
= acpi_evaluate_object(resource
->device
.handle
, "_OFF",
275 if (ACPI_FAILURE(status
))
278 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Power resource [%s] turned off\n",
283 static int acpi_power_off_unlocked(struct acpi_power_resource
*resource
)
287 if (!resource
->ref_count
) {
288 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
289 "Power resource [%s] already off\n",
294 if (--resource
->ref_count
) {
295 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
296 "Power resource [%s] still in use\n",
299 result
= __acpi_power_off(resource
);
301 resource
->ref_count
++;
306 static int acpi_power_off(struct acpi_power_resource
*resource
)
310 mutex_lock(&resource
->resource_lock
);
311 result
= acpi_power_off_unlocked(resource
);
312 mutex_unlock(&resource
->resource_lock
);
316 static int acpi_power_off_list(struct list_head
*list
)
318 struct acpi_power_resource_entry
*entry
;
321 list_for_each_entry_reverse(entry
, list
, node
) {
322 result
= acpi_power_off(entry
->resource
);
329 list_for_each_entry_continue(entry
, list
, node
)
330 acpi_power_on(entry
->resource
);
335 static int acpi_power_on_list(struct list_head
*list
)
337 struct acpi_power_resource_entry
*entry
;
340 list_for_each_entry(entry
, list
, node
) {
341 result
= acpi_power_on(entry
->resource
);
348 list_for_each_entry_continue_reverse(entry
, list
, node
)
349 acpi_power_off(entry
->resource
);
354 static struct attribute
*attrs
[] = {
358 static struct attribute_group attr_groups
[] = {
360 .name
= "power_resources_D0",
364 .name
= "power_resources_D1",
368 .name
= "power_resources_D2",
371 [ACPI_STATE_D3_HOT
] = {
372 .name
= "power_resources_D3hot",
377 static struct attribute_group wakeup_attr_group
= {
378 .name
= "power_resources_wakeup",
382 static void acpi_power_hide_list(struct acpi_device
*adev
,
383 struct list_head
*resources
,
384 struct attribute_group
*attr_group
)
386 struct acpi_power_resource_entry
*entry
;
388 if (list_empty(resources
))
391 list_for_each_entry_reverse(entry
, resources
, node
) {
392 struct acpi_device
*res_dev
= &entry
->resource
->device
;
394 sysfs_remove_link_from_group(&adev
->dev
.kobj
,
396 dev_name(&res_dev
->dev
));
398 sysfs_remove_group(&adev
->dev
.kobj
, attr_group
);
401 static void acpi_power_expose_list(struct acpi_device
*adev
,
402 struct list_head
*resources
,
403 struct attribute_group
*attr_group
)
405 struct acpi_power_resource_entry
*entry
;
408 if (list_empty(resources
))
411 ret
= sysfs_create_group(&adev
->dev
.kobj
, attr_group
);
415 list_for_each_entry(entry
, resources
, node
) {
416 struct acpi_device
*res_dev
= &entry
->resource
->device
;
418 ret
= sysfs_add_link_to_group(&adev
->dev
.kobj
,
421 dev_name(&res_dev
->dev
));
423 acpi_power_hide_list(adev
, resources
, attr_group
);
429 static void acpi_power_expose_hide(struct acpi_device
*adev
,
430 struct list_head
*resources
,
431 struct attribute_group
*attr_group
,
435 acpi_power_expose_list(adev
, resources
, attr_group
);
437 acpi_power_hide_list(adev
, resources
, attr_group
);
440 void acpi_power_add_remove_device(struct acpi_device
*adev
, bool add
)
444 if (adev
->wakeup
.flags
.valid
)
445 acpi_power_expose_hide(adev
, &adev
->wakeup
.resources
,
446 &wakeup_attr_group
, add
);
448 if (!adev
->power
.flags
.power_resources
)
451 for (state
= ACPI_STATE_D0
; state
<= ACPI_STATE_D3_HOT
; state
++)
452 acpi_power_expose_hide(adev
,
453 &adev
->power
.states
[state
].resources
,
454 &attr_groups
[state
], add
);
457 int acpi_power_wakeup_list_init(struct list_head
*list
, int *system_level_p
)
459 struct acpi_power_resource_entry
*entry
;
460 int system_level
= 5;
462 list_for_each_entry(entry
, list
, node
) {
463 struct acpi_power_resource
*resource
= entry
->resource
;
464 acpi_handle handle
= resource
->device
.handle
;
468 mutex_lock(&resource
->resource_lock
);
470 result
= acpi_power_get_state(handle
, &state
);
472 mutex_unlock(&resource
->resource_lock
);
475 if (state
== ACPI_POWER_RESOURCE_STATE_ON
) {
476 resource
->ref_count
++;
477 resource
->wakeup_enabled
= true;
479 if (system_level
> resource
->system_level
)
480 system_level
= resource
->system_level
;
482 mutex_unlock(&resource
->resource_lock
);
484 *system_level_p
= system_level
;
488 /* --------------------------------------------------------------------------
489 Device Power Management
490 -------------------------------------------------------------------------- */
493 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
494 * ACPI 3.0) _PSW (Power State Wake)
495 * @dev: Device to handle.
496 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
497 * @sleep_state: Target sleep state of the system.
498 * @dev_state: Target power state of the device.
500 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
501 * State Wake) for the device, if present. On failure reset the device's
502 * wakeup.flags.valid flag.
505 * 0 if either _DSW or _PSW has been successfully executed
506 * 0 if neither _DSW nor _PSW has been found
507 * -ENODEV if the execution of either _DSW or _PSW has failed
509 int acpi_device_sleep_wake(struct acpi_device
*dev
,
510 int enable
, int sleep_state
, int dev_state
)
512 union acpi_object in_arg
[3];
513 struct acpi_object_list arg_list
= { 3, in_arg
};
514 acpi_status status
= AE_OK
;
517 * Try to execute _DSW first.
519 * Three agruments are needed for the _DSW object:
520 * Argument 0: enable/disable the wake capabilities
521 * Argument 1: target system state
522 * Argument 2: target device state
523 * When _DSW object is called to disable the wake capabilities, maybe
524 * the first argument is filled. The values of the other two agruments
527 in_arg
[0].type
= ACPI_TYPE_INTEGER
;
528 in_arg
[0].integer
.value
= enable
;
529 in_arg
[1].type
= ACPI_TYPE_INTEGER
;
530 in_arg
[1].integer
.value
= sleep_state
;
531 in_arg
[2].type
= ACPI_TYPE_INTEGER
;
532 in_arg
[2].integer
.value
= dev_state
;
533 status
= acpi_evaluate_object(dev
->handle
, "_DSW", &arg_list
, NULL
);
534 if (ACPI_SUCCESS(status
)) {
536 } else if (status
!= AE_NOT_FOUND
) {
537 printk(KERN_ERR PREFIX
"_DSW execution failed\n");
538 dev
->wakeup
.flags
.valid
= 0;
543 status
= acpi_execute_simple_method(dev
->handle
, "_PSW", enable
);
544 if (ACPI_FAILURE(status
) && (status
!= AE_NOT_FOUND
)) {
545 printk(KERN_ERR PREFIX
"_PSW execution failed\n");
546 dev
->wakeup
.flags
.valid
= 0;
554 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
555 * 1. Power on the power resources required for the wakeup device
556 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
557 * State Wake) for the device, if present
559 int acpi_enable_wakeup_device_power(struct acpi_device
*dev
, int sleep_state
)
561 struct acpi_power_resource_entry
*entry
;
564 if (!dev
|| !dev
->wakeup
.flags
.valid
)
567 mutex_lock(&acpi_device_lock
);
569 if (dev
->wakeup
.prepare_count
++)
572 list_for_each_entry(entry
, &dev
->wakeup
.resources
, node
) {
573 struct acpi_power_resource
*resource
= entry
->resource
;
575 mutex_lock(&resource
->resource_lock
);
577 if (!resource
->wakeup_enabled
) {
578 err
= acpi_power_on_unlocked(resource
);
580 resource
->wakeup_enabled
= true;
583 mutex_unlock(&resource
->resource_lock
);
587 "Cannot turn wakeup power resources on\n");
588 dev
->wakeup
.flags
.valid
= 0;
593 * Passing 3 as the third argument below means the device may be
594 * put into arbitrary power state afterward.
596 err
= acpi_device_sleep_wake(dev
, 1, sleep_state
, 3);
598 dev
->wakeup
.prepare_count
= 0;
601 mutex_unlock(&acpi_device_lock
);
606 * Shutdown a wakeup device, counterpart of above method
607 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
608 * State Wake) for the device, if present
609 * 2. Shutdown down the power resources
611 int acpi_disable_wakeup_device_power(struct acpi_device
*dev
)
613 struct acpi_power_resource_entry
*entry
;
616 if (!dev
|| !dev
->wakeup
.flags
.valid
)
619 mutex_lock(&acpi_device_lock
);
621 if (--dev
->wakeup
.prepare_count
> 0)
625 * Executing the code below even if prepare_count is already zero when
626 * the function is called may be useful, for example for initialisation.
628 if (dev
->wakeup
.prepare_count
< 0)
629 dev
->wakeup
.prepare_count
= 0;
631 err
= acpi_device_sleep_wake(dev
, 0, 0, 0);
635 list_for_each_entry(entry
, &dev
->wakeup
.resources
, node
) {
636 struct acpi_power_resource
*resource
= entry
->resource
;
638 mutex_lock(&resource
->resource_lock
);
640 if (resource
->wakeup_enabled
) {
641 err
= acpi_power_off_unlocked(resource
);
643 resource
->wakeup_enabled
= false;
646 mutex_unlock(&resource
->resource_lock
);
650 "Cannot turn wakeup power resources off\n");
651 dev
->wakeup
.flags
.valid
= 0;
657 mutex_unlock(&acpi_device_lock
);
661 int acpi_power_get_inferred_state(struct acpi_device
*device
, int *state
)
667 if (!device
|| !state
)
671 * We know a device's inferred power state when all the resources
672 * required for a given D-state are 'on'.
674 for (i
= ACPI_STATE_D0
; i
<= ACPI_STATE_D3_HOT
; i
++) {
675 struct list_head
*list
= &device
->power
.states
[i
].resources
;
677 if (list_empty(list
))
680 result
= acpi_power_get_list_state(list
, &list_state
);
684 if (list_state
== ACPI_POWER_RESOURCE_STATE_ON
) {
690 *state
= ACPI_STATE_D3_COLD
;
694 int acpi_power_on_resources(struct acpi_device
*device
, int state
)
696 if (!device
|| state
< ACPI_STATE_D0
|| state
> ACPI_STATE_D3_HOT
)
699 return acpi_power_on_list(&device
->power
.states
[state
].resources
);
702 int acpi_power_transition(struct acpi_device
*device
, int state
)
706 if (!device
|| (state
< ACPI_STATE_D0
) || (state
> ACPI_STATE_D3_COLD
))
709 if (device
->power
.state
== state
|| !device
->flags
.power_manageable
)
712 if ((device
->power
.state
< ACPI_STATE_D0
)
713 || (device
->power
.state
> ACPI_STATE_D3_COLD
))
716 /* TBD: Resources must be ordered. */
719 * First we reference all power resources required in the target list
720 * (e.g. so the device doesn't lose power while transitioning). Then,
721 * we dereference all power resources used in the current list.
723 if (state
< ACPI_STATE_D3_COLD
)
724 result
= acpi_power_on_list(
725 &device
->power
.states
[state
].resources
);
727 if (!result
&& device
->power
.state
< ACPI_STATE_D3_COLD
)
729 &device
->power
.states
[device
->power
.state
].resources
);
731 /* We shouldn't change the state unless the above operations succeed. */
732 device
->power
.state
= result
? ACPI_STATE_UNKNOWN
: state
;
737 static void acpi_release_power_resource(struct device
*dev
)
739 struct acpi_device
*device
= to_acpi_device(dev
);
740 struct acpi_power_resource
*resource
;
742 resource
= container_of(device
, struct acpi_power_resource
, device
);
744 mutex_lock(&power_resource_list_lock
);
745 list_del(&resource
->list_node
);
746 mutex_unlock(&power_resource_list_lock
);
748 acpi_free_pnp_ids(&device
->pnp
);
752 static ssize_t
acpi_power_in_use_show(struct device
*dev
,
753 struct device_attribute
*attr
,
755 struct acpi_power_resource
*resource
;
757 resource
= to_power_resource(to_acpi_device(dev
));
758 return sprintf(buf
, "%u\n", !!resource
->ref_count
);
760 static DEVICE_ATTR(resource_in_use
, 0444, acpi_power_in_use_show
, NULL
);
762 static void acpi_power_sysfs_remove(struct acpi_device
*device
)
764 device_remove_file(&device
->dev
, &dev_attr_resource_in_use
);
767 int acpi_add_power_resource(acpi_handle handle
)
769 struct acpi_power_resource
*resource
;
770 struct acpi_device
*device
= NULL
;
771 union acpi_object acpi_object
;
772 struct acpi_buffer buffer
= { sizeof(acpi_object
), &acpi_object
};
774 int state
, result
= -ENODEV
;
776 acpi_bus_get_device(handle
, &device
);
780 resource
= kzalloc(sizeof(*resource
), GFP_KERNEL
);
784 device
= &resource
->device
;
785 acpi_init_device_object(device
, handle
, ACPI_BUS_TYPE_POWER
,
787 mutex_init(&resource
->resource_lock
);
788 INIT_LIST_HEAD(&resource
->list_node
);
789 resource
->name
= device
->pnp
.bus_id
;
790 strcpy(acpi_device_name(device
), ACPI_POWER_DEVICE_NAME
);
791 strcpy(acpi_device_class(device
), ACPI_POWER_CLASS
);
792 device
->power
.state
= ACPI_STATE_UNKNOWN
;
794 /* Evalute the object to get the system level and resource order. */
795 status
= acpi_evaluate_object(handle
, NULL
, NULL
, &buffer
);
796 if (ACPI_FAILURE(status
))
799 resource
->system_level
= acpi_object
.power_resource
.system_level
;
800 resource
->order
= acpi_object
.power_resource
.resource_order
;
802 result
= acpi_power_get_state(handle
, &state
);
806 printk(KERN_INFO PREFIX
"%s [%s] (%s)\n", acpi_device_name(device
),
807 acpi_device_bid(device
), state
? "on" : "off");
809 device
->flags
.match_driver
= true;
810 result
= acpi_device_add(device
, acpi_release_power_resource
);
814 if (!device_create_file(&device
->dev
, &dev_attr_resource_in_use
))
815 device
->remove
= acpi_power_sysfs_remove
;
817 mutex_lock(&power_resource_list_lock
);
818 list_add(&resource
->list_node
, &acpi_power_resource_list
);
819 mutex_unlock(&power_resource_list_lock
);
820 acpi_device_add_finalize(device
);
824 acpi_release_power_resource(&device
->dev
);
828 #ifdef CONFIG_ACPI_SLEEP
829 void acpi_resume_power_resources(void)
831 struct acpi_power_resource
*resource
;
833 mutex_lock(&power_resource_list_lock
);
835 list_for_each_entry(resource
, &acpi_power_resource_list
, list_node
) {
838 mutex_lock(&resource
->resource_lock
);
840 result
= acpi_power_get_state(resource
->device
.handle
, &state
);
842 mutex_unlock(&resource
->resource_lock
);
846 if (state
== ACPI_POWER_RESOURCE_STATE_OFF
847 && resource
->ref_count
) {
848 dev_info(&resource
->device
.dev
, "Turning ON\n");
849 __acpi_power_on(resource
);
850 } else if (state
== ACPI_POWER_RESOURCE_STATE_ON
851 && !resource
->ref_count
) {
852 dev_info(&resource
->device
.dev
, "Turning OFF\n");
853 __acpi_power_off(resource
);
856 mutex_unlock(&resource
->resource_lock
);
859 mutex_unlock(&power_resource_list_lock
);