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 <acpi/acpi_bus.h>
45 #include <acpi/acpi_drivers.h>
49 #define PREFIX "ACPI: "
51 #define _COMPONENT ACPI_POWER_COMPONENT
52 ACPI_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
61 static int acpi_power_add(struct acpi_device
*device
);
62 static int acpi_power_remove(struct acpi_device
*device
, int type
);
64 static const struct acpi_device_id power_device_ids
[] = {
68 MODULE_DEVICE_TABLE(acpi
, power_device_ids
);
70 #ifdef CONFIG_PM_SLEEP
71 static int acpi_power_resume(struct device
*dev
);
73 static SIMPLE_DEV_PM_OPS(acpi_power_pm
, NULL
, acpi_power_resume
);
75 static struct acpi_driver acpi_power_driver
= {
77 .class = ACPI_POWER_CLASS
,
78 .ids
= power_device_ids
,
80 .add
= acpi_power_add
,
81 .remove
= acpi_power_remove
,
83 .drv
.pm
= &acpi_power_pm
,
87 * A power managed device
88 * A device may rely on multiple power resources.
90 struct acpi_power_managed_device
{
91 struct device
*dev
; /* The physical device */
95 struct acpi_power_resource_device
{
96 struct acpi_power_managed_device
*device
;
97 struct acpi_power_resource_device
*next
;
100 struct acpi_power_resource
{
101 struct acpi_device
* device
;
105 unsigned int ref_count
;
106 struct mutex resource_lock
;
108 /* List of devices relying on this power resource */
109 struct acpi_power_resource_device
*devices
;
110 struct mutex devices_lock
;
113 static struct list_head acpi_power_resource_list
;
115 /* --------------------------------------------------------------------------
116 Power Resource Management
117 -------------------------------------------------------------------------- */
120 acpi_power_get_context(acpi_handle handle
,
121 struct acpi_power_resource
**resource
)
124 struct acpi_device
*device
= NULL
;
130 result
= acpi_bus_get_device(handle
, &device
);
132 printk(KERN_WARNING PREFIX
"Getting context [%p]\n", handle
);
136 *resource
= acpi_driver_data(device
);
143 static int acpi_power_get_state(acpi_handle handle
, int *state
)
145 acpi_status status
= AE_OK
;
146 unsigned long long sta
= 0;
148 struct acpi_buffer buffer
= { sizeof(node_name
), node_name
};
151 if (!handle
|| !state
)
154 status
= acpi_evaluate_integer(handle
, "_STA", NULL
, &sta
);
155 if (ACPI_FAILURE(status
))
158 *state
= (sta
& 0x01)?ACPI_POWER_RESOURCE_STATE_ON
:
159 ACPI_POWER_RESOURCE_STATE_OFF
;
161 acpi_get_name(handle
, ACPI_SINGLE_NAME
, &buffer
);
163 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] is %s\n",
165 *state
? "on" : "off"));
170 static int acpi_power_get_list_state(struct acpi_handle_list
*list
, int *state
)
178 /* The state of the list is 'on' IFF all resources are 'on'. */
180 for (i
= 0; i
< list
->count
; i
++) {
181 struct acpi_power_resource
*resource
;
182 acpi_handle handle
= list
->handles
[i
];
185 result
= acpi_power_get_context(handle
, &resource
);
189 mutex_lock(&resource
->resource_lock
);
191 result
= acpi_power_get_state(handle
, &cur_state
);
193 mutex_unlock(&resource
->resource_lock
);
198 if (cur_state
!= ACPI_POWER_RESOURCE_STATE_ON
)
202 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource list is %s\n",
203 cur_state
? "on" : "off"));
210 /* Resume the device when all power resources in _PR0 are on */
211 static void acpi_power_on_device(struct acpi_power_managed_device
*device
)
213 struct acpi_device
*acpi_dev
;
214 acpi_handle handle
= device
->handle
;
217 if (acpi_bus_get_device(handle
, &acpi_dev
))
220 if(acpi_power_get_inferred_state(acpi_dev
, &state
))
223 if (state
== ACPI_STATE_D0
&& pm_runtime_suspended(device
->dev
))
224 pm_request_resume(device
->dev
);
227 static int __acpi_power_on(struct acpi_power_resource
*resource
)
229 acpi_status status
= AE_OK
;
231 status
= acpi_evaluate_object(resource
->device
->handle
, "_ON", NULL
, NULL
);
232 if (ACPI_FAILURE(status
))
235 /* Update the power resource's _device_ power state */
236 resource
->device
->power
.state
= ACPI_STATE_D0
;
238 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Power resource [%s] turned on\n",
244 static int acpi_power_on(acpi_handle handle
)
247 bool resume_device
= false;
248 struct acpi_power_resource
*resource
= NULL
;
249 struct acpi_power_resource_device
*device_list
;
251 result
= acpi_power_get_context(handle
, &resource
);
255 mutex_lock(&resource
->resource_lock
);
257 if (resource
->ref_count
++) {
258 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
259 "Power resource [%s] already on",
262 result
= __acpi_power_on(resource
);
264 resource
->ref_count
--;
266 resume_device
= true;
269 mutex_unlock(&resource
->resource_lock
);
274 mutex_lock(&resource
->devices_lock
);
276 device_list
= resource
->devices
;
277 while (device_list
) {
278 acpi_power_on_device(device_list
->device
);
279 device_list
= device_list
->next
;
282 mutex_unlock(&resource
->devices_lock
);
287 static int acpi_power_off(acpi_handle handle
)
290 acpi_status status
= AE_OK
;
291 struct acpi_power_resource
*resource
= NULL
;
293 result
= acpi_power_get_context(handle
, &resource
);
297 mutex_lock(&resource
->resource_lock
);
299 if (!resource
->ref_count
) {
300 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
301 "Power resource [%s] already off",
306 if (--resource
->ref_count
) {
307 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
308 "Power resource [%s] still in use\n",
313 status
= acpi_evaluate_object(resource
->device
->handle
, "_OFF", NULL
, NULL
);
314 if (ACPI_FAILURE(status
)) {
317 /* Update the power resource's _device_ power state */
318 resource
->device
->power
.state
= ACPI_STATE_D3
;
320 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
321 "Power resource [%s] turned off\n",
326 mutex_unlock(&resource
->resource_lock
);
331 static void __acpi_power_off_list(struct acpi_handle_list
*list
, int num_res
)
335 for (i
= num_res
- 1; i
>= 0 ; i
--)
336 acpi_power_off(list
->handles
[i
]);
339 static void acpi_power_off_list(struct acpi_handle_list
*list
)
341 __acpi_power_off_list(list
, list
->count
);
344 static int acpi_power_on_list(struct acpi_handle_list
*list
)
349 for (i
= 0; i
< list
->count
; i
++) {
350 result
= acpi_power_on(list
->handles
[i
]);
352 __acpi_power_off_list(list
, i
);
360 static void __acpi_power_resource_unregister_device(struct device
*dev
,
361 acpi_handle res_handle
)
363 struct acpi_power_resource
*resource
= NULL
;
364 struct acpi_power_resource_device
*prev
, *curr
;
366 if (acpi_power_get_context(res_handle
, &resource
))
369 mutex_lock(&resource
->devices_lock
);
371 curr
= resource
->devices
;
373 if (curr
->device
->dev
== dev
) {
375 resource
->devices
= curr
->next
;
377 prev
->next
= curr
->next
;
386 mutex_unlock(&resource
->devices_lock
);
389 /* Unlink dev from all power resources in _PR0 */
390 void acpi_power_resource_unregister_device(struct device
*dev
, acpi_handle handle
)
392 struct acpi_device
*acpi_dev
;
393 struct acpi_handle_list
*list
;
399 if (acpi_bus_get_device(handle
, &acpi_dev
))
402 list
= &acpi_dev
->power
.states
[ACPI_STATE_D0
].resources
;
404 for (i
= 0; i
< list
->count
; i
++)
405 __acpi_power_resource_unregister_device(dev
,
408 EXPORT_SYMBOL_GPL(acpi_power_resource_unregister_device
);
410 static int __acpi_power_resource_register_device(
411 struct acpi_power_managed_device
*powered_device
, acpi_handle handle
)
413 struct acpi_power_resource
*resource
= NULL
;
414 struct acpi_power_resource_device
*power_resource_device
;
417 result
= acpi_power_get_context(handle
, &resource
);
421 power_resource_device
= kzalloc(
422 sizeof(*power_resource_device
), GFP_KERNEL
);
423 if (!power_resource_device
)
426 power_resource_device
->device
= powered_device
;
428 mutex_lock(&resource
->devices_lock
);
429 power_resource_device
->next
= resource
->devices
;
430 resource
->devices
= power_resource_device
;
431 mutex_unlock(&resource
->devices_lock
);
436 /* Link dev to all power resources in _PR0 */
437 int acpi_power_resource_register_device(struct device
*dev
, acpi_handle handle
)
439 struct acpi_device
*acpi_dev
;
440 struct acpi_handle_list
*list
;
441 struct acpi_power_managed_device
*powered_device
;
447 ret
= acpi_bus_get_device(handle
, &acpi_dev
);
449 goto no_power_resource
;
451 if (!acpi_dev
->power
.flags
.power_resources
)
452 goto no_power_resource
;
454 powered_device
= kzalloc(sizeof(*powered_device
), GFP_KERNEL
);
458 powered_device
->dev
= dev
;
459 powered_device
->handle
= handle
;
461 list
= &acpi_dev
->power
.states
[ACPI_STATE_D0
].resources
;
463 for (i
= 0; i
< list
->count
; i
++) {
464 ret
= __acpi_power_resource_register_device(powered_device
,
468 acpi_power_resource_unregister_device(dev
, handle
);
476 printk(KERN_DEBUG PREFIX
"Invalid Power Resource to register!\n");
479 EXPORT_SYMBOL_GPL(acpi_power_resource_register_device
);
482 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
483 * ACPI 3.0) _PSW (Power State Wake)
484 * @dev: Device to handle.
485 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
486 * @sleep_state: Target sleep state of the system.
487 * @dev_state: Target power state of the device.
489 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
490 * State Wake) for the device, if present. On failure reset the device's
491 * wakeup.flags.valid flag.
494 * 0 if either _DSW or _PSW has been successfully executed
495 * 0 if neither _DSW nor _PSW has been found
496 * -ENODEV if the execution of either _DSW or _PSW has failed
498 int acpi_device_sleep_wake(struct acpi_device
*dev
,
499 int enable
, int sleep_state
, int dev_state
)
501 union acpi_object in_arg
[3];
502 struct acpi_object_list arg_list
= { 3, in_arg
};
503 acpi_status status
= AE_OK
;
506 * Try to execute _DSW first.
508 * Three agruments are needed for the _DSW object:
509 * Argument 0: enable/disable the wake capabilities
510 * Argument 1: target system state
511 * Argument 2: target device state
512 * When _DSW object is called to disable the wake capabilities, maybe
513 * the first argument is filled. The values of the other two agruments
516 in_arg
[0].type
= ACPI_TYPE_INTEGER
;
517 in_arg
[0].integer
.value
= enable
;
518 in_arg
[1].type
= ACPI_TYPE_INTEGER
;
519 in_arg
[1].integer
.value
= sleep_state
;
520 in_arg
[2].type
= ACPI_TYPE_INTEGER
;
521 in_arg
[2].integer
.value
= dev_state
;
522 status
= acpi_evaluate_object(dev
->handle
, "_DSW", &arg_list
, NULL
);
523 if (ACPI_SUCCESS(status
)) {
525 } else if (status
!= AE_NOT_FOUND
) {
526 printk(KERN_ERR PREFIX
"_DSW execution failed\n");
527 dev
->wakeup
.flags
.valid
= 0;
533 in_arg
[0].integer
.value
= enable
;
534 status
= acpi_evaluate_object(dev
->handle
, "_PSW", &arg_list
, NULL
);
535 if (ACPI_FAILURE(status
) && (status
!= AE_NOT_FOUND
)) {
536 printk(KERN_ERR PREFIX
"_PSW execution failed\n");
537 dev
->wakeup
.flags
.valid
= 0;
545 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
546 * 1. Power on the power resources required for the wakeup device
547 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
548 * State Wake) for the device, if present
550 int acpi_enable_wakeup_device_power(struct acpi_device
*dev
, int sleep_state
)
554 if (!dev
|| !dev
->wakeup
.flags
.valid
)
557 mutex_lock(&acpi_device_lock
);
559 if (dev
->wakeup
.prepare_count
++)
562 /* Open power resource */
563 for (i
= 0; i
< dev
->wakeup
.resources
.count
; i
++) {
564 int ret
= acpi_power_on(dev
->wakeup
.resources
.handles
[i
]);
566 printk(KERN_ERR PREFIX
"Transition power state\n");
567 dev
->wakeup
.flags
.valid
= 0;
574 * Passing 3 as the third argument below means the device may be placed
575 * in arbitrary power state afterwards.
577 err
= acpi_device_sleep_wake(dev
, 1, sleep_state
, 3);
581 dev
->wakeup
.prepare_count
= 0;
584 mutex_unlock(&acpi_device_lock
);
589 * Shutdown a wakeup device, counterpart of above method
590 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
591 * State Wake) for the device, if present
592 * 2. Shutdown down the power resources
594 int acpi_disable_wakeup_device_power(struct acpi_device
*dev
)
598 if (!dev
|| !dev
->wakeup
.flags
.valid
)
601 mutex_lock(&acpi_device_lock
);
603 if (--dev
->wakeup
.prepare_count
> 0)
607 * Executing the code below even if prepare_count is already zero when
608 * the function is called may be useful, for example for initialisation.
610 if (dev
->wakeup
.prepare_count
< 0)
611 dev
->wakeup
.prepare_count
= 0;
613 err
= acpi_device_sleep_wake(dev
, 0, 0, 0);
617 /* Close power resource */
618 for (i
= 0; i
< dev
->wakeup
.resources
.count
; i
++) {
619 int ret
= acpi_power_off(dev
->wakeup
.resources
.handles
[i
]);
621 printk(KERN_ERR PREFIX
"Transition power state\n");
622 dev
->wakeup
.flags
.valid
= 0;
629 mutex_unlock(&acpi_device_lock
);
633 /* --------------------------------------------------------------------------
634 Device Power Management
635 -------------------------------------------------------------------------- */
637 int acpi_power_get_inferred_state(struct acpi_device
*device
, int *state
)
640 struct acpi_handle_list
*list
= NULL
;
644 if (!device
|| !state
)
648 * We know a device's inferred power state when all the resources
649 * required for a given D-state are 'on'.
651 for (i
= ACPI_STATE_D0
; i
<= ACPI_STATE_D3_HOT
; i
++) {
652 list
= &device
->power
.states
[i
].resources
;
656 result
= acpi_power_get_list_state(list
, &list_state
);
660 if (list_state
== ACPI_POWER_RESOURCE_STATE_ON
) {
666 *state
= ACPI_STATE_D3
;
670 int acpi_power_on_resources(struct acpi_device
*device
, int state
)
672 if (!device
|| state
< ACPI_STATE_D0
|| state
> ACPI_STATE_D3
)
675 return acpi_power_on_list(&device
->power
.states
[state
].resources
);
678 int acpi_power_transition(struct acpi_device
*device
, int state
)
682 if (!device
|| (state
< ACPI_STATE_D0
) || (state
> ACPI_STATE_D3_COLD
))
685 if (device
->power
.state
== state
)
688 if ((device
->power
.state
< ACPI_STATE_D0
)
689 || (device
->power
.state
> ACPI_STATE_D3_COLD
))
692 /* TBD: Resources must be ordered. */
695 * First we reference all power resources required in the target list
696 * (e.g. so the device doesn't lose power while transitioning). Then,
697 * we dereference all power resources used in the current list.
699 if (state
< ACPI_STATE_D3_COLD
)
700 result
= acpi_power_on_list(
701 &device
->power
.states
[state
].resources
);
703 if (!result
&& device
->power
.state
< ACPI_STATE_D3_COLD
)
705 &device
->power
.states
[device
->power
.state
].resources
);
707 /* We shouldn't change the state unless the above operations succeed. */
708 device
->power
.state
= result
? ACPI_STATE_UNKNOWN
: state
;
713 /* --------------------------------------------------------------------------
715 -------------------------------------------------------------------------- */
717 static int acpi_power_add(struct acpi_device
*device
)
719 int result
= 0, state
;
720 acpi_status status
= AE_OK
;
721 struct acpi_power_resource
*resource
= NULL
;
722 union acpi_object acpi_object
;
723 struct acpi_buffer buffer
= { sizeof(acpi_object
), &acpi_object
};
729 resource
= kzalloc(sizeof(struct acpi_power_resource
), GFP_KERNEL
);
733 resource
->device
= device
;
734 mutex_init(&resource
->resource_lock
);
735 mutex_init(&resource
->devices_lock
);
736 strcpy(resource
->name
, device
->pnp
.bus_id
);
737 strcpy(acpi_device_name(device
), ACPI_POWER_DEVICE_NAME
);
738 strcpy(acpi_device_class(device
), ACPI_POWER_CLASS
);
739 device
->driver_data
= resource
;
741 /* Evalute the object to get the system level and resource order. */
742 status
= acpi_evaluate_object(device
->handle
, NULL
, NULL
, &buffer
);
743 if (ACPI_FAILURE(status
)) {
747 resource
->system_level
= acpi_object
.power_resource
.system_level
;
748 resource
->order
= acpi_object
.power_resource
.resource_order
;
750 result
= acpi_power_get_state(device
->handle
, &state
);
755 case ACPI_POWER_RESOURCE_STATE_ON
:
756 device
->power
.state
= ACPI_STATE_D0
;
758 case ACPI_POWER_RESOURCE_STATE_OFF
:
759 device
->power
.state
= ACPI_STATE_D3
;
762 device
->power
.state
= ACPI_STATE_UNKNOWN
;
766 printk(KERN_INFO PREFIX
"%s [%s] (%s)\n", acpi_device_name(device
),
767 acpi_device_bid(device
), state
? "on" : "off");
776 static int acpi_power_remove(struct acpi_device
*device
, int type
)
778 struct acpi_power_resource
*resource
;
783 resource
= acpi_driver_data(device
);
792 #ifdef CONFIG_PM_SLEEP
793 static int acpi_power_resume(struct device
*dev
)
795 int result
= 0, state
;
796 struct acpi_device
*device
;
797 struct acpi_power_resource
*resource
;
802 device
= to_acpi_device(dev
);
803 resource
= acpi_driver_data(device
);
807 mutex_lock(&resource
->resource_lock
);
809 result
= acpi_power_get_state(device
->handle
, &state
);
813 if (state
== ACPI_POWER_RESOURCE_STATE_OFF
&& resource
->ref_count
)
814 result
= __acpi_power_on(resource
);
817 mutex_unlock(&resource
->resource_lock
);
823 int __init
acpi_power_init(void)
825 INIT_LIST_HEAD(&acpi_power_resource_list
);
826 return acpi_bus_register_driver(&acpi_power_driver
);