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/proc_fs.h>
43 #include <linux/seq_file.h>
44 #include <acpi/acpi_bus.h>
45 #include <acpi/acpi_drivers.h>
47 #define _COMPONENT ACPI_POWER_COMPONENT
48 ACPI_MODULE_NAME("power");
49 #define ACPI_POWER_COMPONENT 0x00800000
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
58 #ifdef MODULE_PARAM_PREFIX
59 #undef MODULE_PARAM_PREFIX
61 #define MODULE_PARAM_PREFIX "acpi."
62 int acpi_power_nocheck
;
63 module_param_named(power_nocheck
, acpi_power_nocheck
, bool, 000);
65 static int acpi_power_add(struct acpi_device
*device
);
66 static int acpi_power_remove(struct acpi_device
*device
, int type
);
67 static int acpi_power_resume(struct acpi_device
*device
);
68 static int acpi_power_open_fs(struct inode
*inode
, struct file
*file
);
70 static struct acpi_device_id power_device_ids
[] = {
74 MODULE_DEVICE_TABLE(acpi
, power_device_ids
);
76 static struct acpi_driver acpi_power_driver
= {
78 .class = ACPI_POWER_CLASS
,
79 .ids
= power_device_ids
,
81 .add
= acpi_power_add
,
82 .remove
= acpi_power_remove
,
83 .resume
= acpi_power_resume
,
87 struct acpi_power_reference
{
88 struct list_head node
;
89 struct acpi_device
*device
;
92 struct acpi_power_resource
{
93 struct acpi_device
* device
;
97 struct mutex resource_lock
;
98 struct list_head reference
;
101 static struct list_head acpi_power_resource_list
;
103 static const struct file_operations acpi_power_fops
= {
104 .owner
= THIS_MODULE
,
105 .open
= acpi_power_open_fs
,
108 .release
= single_release
,
111 /* --------------------------------------------------------------------------
112 Power Resource Management
113 -------------------------------------------------------------------------- */
116 acpi_power_get_context(acpi_handle handle
,
117 struct acpi_power_resource
**resource
)
120 struct acpi_device
*device
= NULL
;
126 result
= acpi_bus_get_device(handle
, &device
);
128 printk(KERN_WARNING PREFIX
"Getting context [%p]\n", handle
);
132 *resource
= acpi_driver_data(device
);
139 static int acpi_power_get_state(acpi_handle handle
, int *state
)
141 acpi_status status
= AE_OK
;
142 unsigned long sta
= 0;
145 if (!handle
|| !state
)
148 status
= acpi_evaluate_integer(handle
, "_STA", NULL
, &sta
);
149 if (ACPI_FAILURE(status
))
152 *state
= (sta
& 0x01)?ACPI_POWER_RESOURCE_STATE_ON
:
153 ACPI_POWER_RESOURCE_STATE_OFF
;
155 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] is %s\n",
156 acpi_ut_get_node_name(handle
), state
? "on" : "off"));
161 static int acpi_power_get_list_state(struct acpi_handle_list
*list
, int *state
)
163 int result
= 0, state1
;
170 /* The state of the list is 'on' IFF all resources are 'on'. */
173 for (i
= 0; i
< list
->count
; i
++) {
175 * The state of the power resource can be obtained by
176 * using the ACPI handle. In such case it is unnecessary to
177 * get the Power resource first and then get its state again.
179 result
= acpi_power_get_state(list
->handles
[i
], &state1
);
185 if (*state
!= ACPI_POWER_RESOURCE_STATE_ON
)
189 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource list is %s\n",
190 *state
? "on" : "off"));
195 static int acpi_power_on(acpi_handle handle
, struct acpi_device
*dev
)
197 int result
= 0, state
;
199 acpi_status status
= AE_OK
;
200 struct acpi_power_resource
*resource
= NULL
;
201 struct list_head
*node
, *next
;
202 struct acpi_power_reference
*ref
;
205 result
= acpi_power_get_context(handle
, &resource
);
209 mutex_lock(&resource
->resource_lock
);
210 list_for_each_safe(node
, next
, &resource
->reference
) {
211 ref
= container_of(node
, struct acpi_power_reference
, node
);
212 if (dev
->handle
== ref
->device
->handle
) {
213 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Device [%s] already referenced by resource [%s]\n",
214 dev
->pnp
.bus_id
, resource
->name
));
221 ref
= kmalloc(sizeof (struct acpi_power_reference
),
222 irqs_disabled() ? GFP_ATOMIC
: GFP_KERNEL
);
224 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "kmalloc() failed\n"));
225 mutex_unlock(&resource
->resource_lock
);
228 list_add_tail(&ref
->node
, &resource
->reference
);
230 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Device [%s] added to resource [%s] references\n",
231 dev
->pnp
.bus_id
, resource
->name
));
233 mutex_unlock(&resource
->resource_lock
);
235 status
= acpi_evaluate_object(resource
->device
->handle
, "_ON", NULL
, NULL
);
236 if (ACPI_FAILURE(status
))
239 if (!acpi_power_nocheck
) {
241 * If acpi_power_nocheck is set, it is unnecessary to check
242 * the power state after power transition.
244 result
= acpi_power_get_state(resource
->device
->handle
,
248 if (state
!= ACPI_POWER_RESOURCE_STATE_ON
)
251 /* Update the power resource's _device_ power state */
252 resource
->device
->power
.state
= ACPI_STATE_D0
;
254 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] turned on\n",
259 static int acpi_power_off_device(acpi_handle handle
, struct acpi_device
*dev
)
261 int result
= 0, state
;
262 acpi_status status
= AE_OK
;
263 struct acpi_power_resource
*resource
= NULL
;
264 struct list_head
*node
, *next
;
265 struct acpi_power_reference
*ref
;
268 result
= acpi_power_get_context(handle
, &resource
);
272 mutex_lock(&resource
->resource_lock
);
273 list_for_each_safe(node
, next
, &resource
->reference
) {
274 ref
= container_of(node
, struct acpi_power_reference
, node
);
275 if (dev
->handle
== ref
->device
->handle
) {
276 list_del(&ref
->node
);
278 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Device [%s] removed from resource [%s] references\n",
279 dev
->pnp
.bus_id
, resource
->name
));
284 if (!list_empty(&resource
->reference
)) {
285 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Cannot turn resource [%s] off - resource is in use\n",
287 mutex_unlock(&resource
->resource_lock
);
290 mutex_unlock(&resource
->resource_lock
);
292 status
= acpi_evaluate_object(resource
->device
->handle
, "_OFF", NULL
, NULL
);
293 if (ACPI_FAILURE(status
))
296 if (!acpi_power_nocheck
) {
298 * If acpi_power_nocheck is set, it is unnecessary to check
299 * the power state after power transition.
301 result
= acpi_power_get_state(handle
, &state
);
304 if (state
!= ACPI_POWER_RESOURCE_STATE_OFF
)
308 /* Update the power resource's _device_ power state */
309 resource
->device
->power
.state
= ACPI_STATE_D3
;
311 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] turned off\n",
318 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
319 * ACPI 3.0) _PSW (Power State Wake)
320 * @dev: Device to handle.
321 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
322 * @sleep_state: Target sleep state of the system.
323 * @dev_state: Target power state of the device.
325 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
326 * State Wake) for the device, if present. On failure reset the device's
327 * wakeup.flags.valid flag.
330 * 0 if either _DSW or _PSW has been successfully executed
331 * 0 if neither _DSW nor _PSW has been found
332 * -ENODEV if the execution of either _DSW or _PSW has failed
334 int acpi_device_sleep_wake(struct acpi_device
*dev
,
335 int enable
, int sleep_state
, int dev_state
)
337 union acpi_object in_arg
[3];
338 struct acpi_object_list arg_list
= { 3, in_arg
};
339 acpi_status status
= AE_OK
;
342 * Try to execute _DSW first.
344 * Three agruments are needed for the _DSW object:
345 * Argument 0: enable/disable the wake capabilities
346 * Argument 1: target system state
347 * Argument 2: target device state
348 * When _DSW object is called to disable the wake capabilities, maybe
349 * the first argument is filled. The values of the other two agruments
352 in_arg
[0].type
= ACPI_TYPE_INTEGER
;
353 in_arg
[0].integer
.value
= enable
;
354 in_arg
[1].type
= ACPI_TYPE_INTEGER
;
355 in_arg
[1].integer
.value
= sleep_state
;
356 in_arg
[2].type
= ACPI_TYPE_INTEGER
;
357 in_arg
[2].integer
.value
= dev_state
;
358 status
= acpi_evaluate_object(dev
->handle
, "_DSW", &arg_list
, NULL
);
359 if (ACPI_SUCCESS(status
)) {
361 } else if (status
!= AE_NOT_FOUND
) {
362 printk(KERN_ERR PREFIX
"_DSW execution failed\n");
363 dev
->wakeup
.flags
.valid
= 0;
369 in_arg
[0].integer
.value
= enable
;
370 status
= acpi_evaluate_object(dev
->handle
, "_PSW", &arg_list
, NULL
);
371 if (ACPI_FAILURE(status
) && (status
!= AE_NOT_FOUND
)) {
372 printk(KERN_ERR PREFIX
"_PSW execution failed\n");
373 dev
->wakeup
.flags
.valid
= 0;
381 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
382 * 1. Power on the power resources required for the wakeup device
383 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
384 * State Wake) for the device, if present
386 int acpi_enable_wakeup_device_power(struct acpi_device
*dev
, int sleep_state
)
390 if (!dev
|| !dev
->wakeup
.flags
.valid
)
394 * Do not execute the code below twice in a row without calling
395 * acpi_disable_wakeup_device_power() in between for the same device
397 if (dev
->wakeup
.flags
.prepared
)
400 /* Open power resource */
401 for (i
= 0; i
< dev
->wakeup
.resources
.count
; i
++) {
402 int ret
= acpi_power_on(dev
->wakeup
.resources
.handles
[i
], dev
);
404 printk(KERN_ERR PREFIX
"Transition power state\n");
405 dev
->wakeup
.flags
.valid
= 0;
411 * Passing 3 as the third argument below means the device may be placed
412 * in arbitrary power state afterwards.
414 err
= acpi_device_sleep_wake(dev
, 1, sleep_state
, 3);
416 dev
->wakeup
.flags
.prepared
= 1;
422 * Shutdown a wakeup device, counterpart of above method
423 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
424 * State Wake) for the device, if present
425 * 2. Shutdown down the power resources
427 int acpi_disable_wakeup_device_power(struct acpi_device
*dev
)
431 if (!dev
|| !dev
->wakeup
.flags
.valid
)
435 * Do not execute the code below twice in a row without calling
436 * acpi_enable_wakeup_device_power() in between for the same device
438 if (!dev
->wakeup
.flags
.prepared
)
441 dev
->wakeup
.flags
.prepared
= 0;
443 ret
= acpi_device_sleep_wake(dev
, 0, 0, 0);
447 /* Close power resource */
448 for (i
= 0; i
< dev
->wakeup
.resources
.count
; i
++) {
449 ret
= acpi_power_off_device(dev
->wakeup
.resources
.handles
[i
], dev
);
451 printk(KERN_ERR PREFIX
"Transition power state\n");
452 dev
->wakeup
.flags
.valid
= 0;
460 /* --------------------------------------------------------------------------
461 Device Power Management
462 -------------------------------------------------------------------------- */
464 int acpi_power_get_inferred_state(struct acpi_device
*device
)
467 struct acpi_handle_list
*list
= NULL
;
475 device
->power
.state
= ACPI_STATE_UNKNOWN
;
478 * We know a device's inferred power state when all the resources
479 * required for a given D-state are 'on'.
481 for (i
= ACPI_STATE_D0
; i
< ACPI_STATE_D3
; i
++) {
482 list
= &device
->power
.states
[i
].resources
;
486 result
= acpi_power_get_list_state(list
, &list_state
);
490 if (list_state
== ACPI_POWER_RESOURCE_STATE_ON
) {
491 device
->power
.state
= i
;
496 device
->power
.state
= ACPI_STATE_D3
;
501 int acpi_power_transition(struct acpi_device
*device
, int state
)
504 struct acpi_handle_list
*cl
= NULL
; /* Current Resources */
505 struct acpi_handle_list
*tl
= NULL
; /* Target Resources */
509 if (!device
|| (state
< ACPI_STATE_D0
) || (state
> ACPI_STATE_D3
))
512 if ((device
->power
.state
< ACPI_STATE_D0
)
513 || (device
->power
.state
> ACPI_STATE_D3
))
516 cl
= &device
->power
.states
[device
->power
.state
].resources
;
517 tl
= &device
->power
.states
[state
].resources
;
519 if (!cl
->count
&& !tl
->count
) {
524 /* TBD: Resources must be ordered. */
527 * First we reference all power resources required in the target list
528 * (e.g. so the device doesn't lose power while transitioning).
530 for (i
= 0; i
< tl
->count
; i
++) {
531 result
= acpi_power_on(tl
->handles
[i
], device
);
536 if (device
->power
.state
== state
) {
541 * Then we dereference all power resources used in the current list.
543 for (i
= 0; i
< cl
->count
; i
++) {
544 result
= acpi_power_off_device(cl
->handles
[i
], device
);
551 device
->power
.state
= ACPI_STATE_UNKNOWN
;
553 /* We shouldn't change the state till all above operations succeed */
554 device
->power
.state
= state
;
560 /* --------------------------------------------------------------------------
562 -------------------------------------------------------------------------- */
564 static struct proc_dir_entry
*acpi_power_dir
;
566 static int acpi_power_seq_show(struct seq_file
*seq
, void *offset
)
569 int result
= 0, state
;
570 struct acpi_power_resource
*resource
= NULL
;
571 struct list_head
*node
, *next
;
572 struct acpi_power_reference
*ref
;
575 resource
= seq
->private;
580 result
= acpi_power_get_state(resource
->device
->handle
, &state
);
584 seq_puts(seq
, "state: ");
586 case ACPI_POWER_RESOURCE_STATE_ON
:
587 seq_puts(seq
, "on\n");
589 case ACPI_POWER_RESOURCE_STATE_OFF
:
590 seq_puts(seq
, "off\n");
593 seq_puts(seq
, "unknown\n");
597 mutex_lock(&resource
->resource_lock
);
598 list_for_each_safe(node
, next
, &resource
->reference
) {
599 ref
= container_of(node
, struct acpi_power_reference
, node
);
602 mutex_unlock(&resource
->resource_lock
);
604 seq_printf(seq
, "system level: S%d\n"
606 "reference count: %d\n",
607 resource
->system_level
,
608 resource
->order
, count
);
614 static int acpi_power_open_fs(struct inode
*inode
, struct file
*file
)
616 return single_open(file
, acpi_power_seq_show
, PDE(inode
)->data
);
619 static int acpi_power_add_fs(struct acpi_device
*device
)
621 struct proc_dir_entry
*entry
= NULL
;
627 if (!acpi_device_dir(device
)) {
628 acpi_device_dir(device
) = proc_mkdir(acpi_device_bid(device
),
630 if (!acpi_device_dir(device
))
635 entry
= proc_create_data(ACPI_POWER_FILE_STATUS
,
636 S_IRUGO
, acpi_device_dir(device
),
637 &acpi_power_fops
, acpi_driver_data(device
));
643 static int acpi_power_remove_fs(struct acpi_device
*device
)
646 if (acpi_device_dir(device
)) {
647 remove_proc_entry(ACPI_POWER_FILE_STATUS
,
648 acpi_device_dir(device
));
649 remove_proc_entry(acpi_device_bid(device
), acpi_power_dir
);
650 acpi_device_dir(device
) = NULL
;
656 /* --------------------------------------------------------------------------
658 -------------------------------------------------------------------------- */
660 static int acpi_power_add(struct acpi_device
*device
)
662 int result
= 0, state
;
663 acpi_status status
= AE_OK
;
664 struct acpi_power_resource
*resource
= NULL
;
665 union acpi_object acpi_object
;
666 struct acpi_buffer buffer
= { sizeof(acpi_object
), &acpi_object
};
672 resource
= kzalloc(sizeof(struct acpi_power_resource
), GFP_KERNEL
);
676 resource
->device
= device
;
677 mutex_init(&resource
->resource_lock
);
678 INIT_LIST_HEAD(&resource
->reference
);
679 strcpy(resource
->name
, device
->pnp
.bus_id
);
680 strcpy(acpi_device_name(device
), ACPI_POWER_DEVICE_NAME
);
681 strcpy(acpi_device_class(device
), ACPI_POWER_CLASS
);
682 device
->driver_data
= resource
;
684 /* Evalute the object to get the system level and resource order. */
685 status
= acpi_evaluate_object(device
->handle
, NULL
, NULL
, &buffer
);
686 if (ACPI_FAILURE(status
)) {
690 resource
->system_level
= acpi_object
.power_resource
.system_level
;
691 resource
->order
= acpi_object
.power_resource
.resource_order
;
693 result
= acpi_power_get_state(device
->handle
, &state
);
698 case ACPI_POWER_RESOURCE_STATE_ON
:
699 device
->power
.state
= ACPI_STATE_D0
;
701 case ACPI_POWER_RESOURCE_STATE_OFF
:
702 device
->power
.state
= ACPI_STATE_D3
;
705 device
->power
.state
= ACPI_STATE_UNKNOWN
;
709 result
= acpi_power_add_fs(device
);
713 printk(KERN_INFO PREFIX
"%s [%s] (%s)\n", acpi_device_name(device
),
714 acpi_device_bid(device
), state
? "on" : "off");
723 static int acpi_power_remove(struct acpi_device
*device
, int type
)
725 struct acpi_power_resource
*resource
= NULL
;
726 struct list_head
*node
, *next
;
729 if (!device
|| !acpi_driver_data(device
))
732 resource
= acpi_driver_data(device
);
734 acpi_power_remove_fs(device
);
736 mutex_lock(&resource
->resource_lock
);
737 list_for_each_safe(node
, next
, &resource
->reference
) {
738 struct acpi_power_reference
*ref
= container_of(node
, struct acpi_power_reference
, node
);
739 list_del(&ref
->node
);
742 mutex_unlock(&resource
->resource_lock
);
749 static int acpi_power_resume(struct acpi_device
*device
)
751 int result
= 0, state
;
752 struct acpi_power_resource
*resource
= NULL
;
753 struct acpi_power_reference
*ref
;
755 if (!device
|| !acpi_driver_data(device
))
758 resource
= acpi_driver_data(device
);
760 result
= acpi_power_get_state(device
->handle
, &state
);
764 mutex_lock(&resource
->resource_lock
);
765 if (state
== ACPI_POWER_RESOURCE_STATE_OFF
&&
766 !list_empty(&resource
->reference
)) {
767 ref
= container_of(resource
->reference
.next
, struct acpi_power_reference
, node
);
768 mutex_unlock(&resource
->resource_lock
);
769 result
= acpi_power_on(device
->handle
, ref
->device
);
773 mutex_unlock(&resource
->resource_lock
);
777 static int __init
acpi_power_init(void)
785 INIT_LIST_HEAD(&acpi_power_resource_list
);
787 acpi_power_dir
= proc_mkdir(ACPI_POWER_CLASS
, acpi_root_dir
);
791 result
= acpi_bus_register_driver(&acpi_power_driver
);
793 remove_proc_entry(ACPI_POWER_CLASS
, acpi_root_dir
);
800 subsys_initcall(acpi_power_init
);