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_CLASS "power_resource"
50 #define ACPI_POWER_DEVICE_NAME "Power Resource"
51 #define ACPI_POWER_FILE_INFO "info"
52 #define ACPI_POWER_FILE_STATUS "state"
53 #define ACPI_POWER_RESOURCE_STATE_OFF 0x00
54 #define ACPI_POWER_RESOURCE_STATE_ON 0x01
55 #define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
57 #ifdef MODULE_PARAM_PREFIX
58 #undef MODULE_PARAM_PREFIX
60 #define MODULE_PARAM_PREFIX "acpi."
61 int acpi_power_nocheck
;
62 module_param_named(power_nocheck
, acpi_power_nocheck
, bool, 000);
64 static int acpi_power_add(struct acpi_device
*device
);
65 static int acpi_power_remove(struct acpi_device
*device
, int type
);
66 static int acpi_power_resume(struct acpi_device
*device
);
67 static int acpi_power_open_fs(struct inode
*inode
, struct file
*file
);
69 static struct acpi_device_id power_device_ids
[] = {
73 MODULE_DEVICE_TABLE(acpi
, power_device_ids
);
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
,
82 .resume
= acpi_power_resume
,
86 struct acpi_power_reference
{
87 struct list_head node
;
88 struct acpi_device
*device
;
91 struct acpi_power_resource
{
92 struct acpi_device
* device
;
96 struct mutex resource_lock
;
97 struct list_head reference
;
100 static struct list_head acpi_power_resource_list
;
102 static const struct file_operations acpi_power_fops
= {
103 .owner
= THIS_MODULE
,
104 .open
= acpi_power_open_fs
,
107 .release
= single_release
,
110 /* --------------------------------------------------------------------------
111 Power Resource Management
112 -------------------------------------------------------------------------- */
115 acpi_power_get_context(acpi_handle handle
,
116 struct acpi_power_resource
**resource
)
119 struct acpi_device
*device
= NULL
;
125 result
= acpi_bus_get_device(handle
, &device
);
127 printk(KERN_WARNING PREFIX
"Getting context [%p]\n", handle
);
131 *resource
= acpi_driver_data(device
);
138 static int acpi_power_get_state(acpi_handle handle
, int *state
)
140 acpi_status status
= AE_OK
;
141 unsigned long long sta
= 0;
144 if (!handle
|| !state
)
147 status
= acpi_evaluate_integer(handle
, "_STA", NULL
, &sta
);
148 if (ACPI_FAILURE(status
))
151 *state
= (sta
& 0x01)?ACPI_POWER_RESOURCE_STATE_ON
:
152 ACPI_POWER_RESOURCE_STATE_OFF
;
154 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] is %s\n",
155 acpi_ut_get_node_name(handle
), state
? "on" : "off"));
160 static int acpi_power_get_list_state(struct acpi_handle_list
*list
, int *state
)
162 int result
= 0, state1
;
169 /* The state of the list is 'on' IFF all resources are 'on'. */
172 for (i
= 0; i
< list
->count
; i
++) {
174 * The state of the power resource can be obtained by
175 * using the ACPI handle. In such case it is unnecessary to
176 * get the Power resource first and then get its state again.
178 result
= acpi_power_get_state(list
->handles
[i
], &state1
);
184 if (*state
!= ACPI_POWER_RESOURCE_STATE_ON
)
188 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource list is %s\n",
189 *state
? "on" : "off"));
194 static int acpi_power_on(acpi_handle handle
, struct acpi_device
*dev
)
196 int result
= 0, state
;
198 acpi_status status
= AE_OK
;
199 struct acpi_power_resource
*resource
= NULL
;
200 struct list_head
*node
, *next
;
201 struct acpi_power_reference
*ref
;
204 result
= acpi_power_get_context(handle
, &resource
);
208 mutex_lock(&resource
->resource_lock
);
209 list_for_each_safe(node
, next
, &resource
->reference
) {
210 ref
= container_of(node
, struct acpi_power_reference
, node
);
211 if (dev
->handle
== ref
->device
->handle
) {
212 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Device [%s] already referenced by resource [%s]\n",
213 dev
->pnp
.bus_id
, resource
->name
));
220 ref
= kmalloc(sizeof (struct acpi_power_reference
),
221 irqs_disabled() ? GFP_ATOMIC
: GFP_KERNEL
);
223 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "kmalloc() failed\n"));
224 mutex_unlock(&resource
->resource_lock
);
227 list_add_tail(&ref
->node
, &resource
->reference
);
229 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Device [%s] added to resource [%s] references\n",
230 dev
->pnp
.bus_id
, resource
->name
));
232 mutex_unlock(&resource
->resource_lock
);
234 status
= acpi_evaluate_object(resource
->device
->handle
, "_ON", NULL
, NULL
);
235 if (ACPI_FAILURE(status
))
238 if (!acpi_power_nocheck
) {
240 * If acpi_power_nocheck is set, it is unnecessary to check
241 * the power state after power transition.
243 result
= acpi_power_get_state(resource
->device
->handle
,
247 if (state
!= ACPI_POWER_RESOURCE_STATE_ON
)
250 /* Update the power resource's _device_ power state */
251 resource
->device
->power
.state
= ACPI_STATE_D0
;
253 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] turned on\n",
258 static int acpi_power_off_device(acpi_handle handle
, struct acpi_device
*dev
)
260 int result
= 0, state
;
261 acpi_status status
= AE_OK
;
262 struct acpi_power_resource
*resource
= NULL
;
263 struct list_head
*node
, *next
;
264 struct acpi_power_reference
*ref
;
267 result
= acpi_power_get_context(handle
, &resource
);
271 mutex_lock(&resource
->resource_lock
);
272 list_for_each_safe(node
, next
, &resource
->reference
) {
273 ref
= container_of(node
, struct acpi_power_reference
, node
);
274 if (dev
->handle
== ref
->device
->handle
) {
275 list_del(&ref
->node
);
277 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Device [%s] removed from resource [%s] references\n",
278 dev
->pnp
.bus_id
, resource
->name
));
283 if (!list_empty(&resource
->reference
)) {
284 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Cannot turn resource [%s] off - resource is in use\n",
286 mutex_unlock(&resource
->resource_lock
);
289 mutex_unlock(&resource
->resource_lock
);
291 status
= acpi_evaluate_object(resource
->device
->handle
, "_OFF", NULL
, NULL
);
292 if (ACPI_FAILURE(status
))
295 if (!acpi_power_nocheck
) {
297 * If acpi_power_nocheck is set, it is unnecessary to check
298 * the power state after power transition.
300 result
= acpi_power_get_state(handle
, &state
);
303 if (state
!= ACPI_POWER_RESOURCE_STATE_OFF
)
307 /* Update the power resource's _device_ power state */
308 resource
->device
->power
.state
= ACPI_STATE_D3
;
310 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Resource [%s] turned off\n",
317 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
318 * ACPI 3.0) _PSW (Power State Wake)
319 * @dev: Device to handle.
320 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
321 * @sleep_state: Target sleep state of the system.
322 * @dev_state: Target power state of the device.
324 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
325 * State Wake) for the device, if present. On failure reset the device's
326 * wakeup.flags.valid flag.
329 * 0 if either _DSW or _PSW has been successfully executed
330 * 0 if neither _DSW nor _PSW has been found
331 * -ENODEV if the execution of either _DSW or _PSW has failed
333 int acpi_device_sleep_wake(struct acpi_device
*dev
,
334 int enable
, int sleep_state
, int dev_state
)
336 union acpi_object in_arg
[3];
337 struct acpi_object_list arg_list
= { 3, in_arg
};
338 acpi_status status
= AE_OK
;
341 * Try to execute _DSW first.
343 * Three agruments are needed for the _DSW object:
344 * Argument 0: enable/disable the wake capabilities
345 * Argument 1: target system state
346 * Argument 2: target device state
347 * When _DSW object is called to disable the wake capabilities, maybe
348 * the first argument is filled. The values of the other two agruments
351 in_arg
[0].type
= ACPI_TYPE_INTEGER
;
352 in_arg
[0].integer
.value
= enable
;
353 in_arg
[1].type
= ACPI_TYPE_INTEGER
;
354 in_arg
[1].integer
.value
= sleep_state
;
355 in_arg
[2].type
= ACPI_TYPE_INTEGER
;
356 in_arg
[2].integer
.value
= dev_state
;
357 status
= acpi_evaluate_object(dev
->handle
, "_DSW", &arg_list
, NULL
);
358 if (ACPI_SUCCESS(status
)) {
360 } else if (status
!= AE_NOT_FOUND
) {
361 printk(KERN_ERR PREFIX
"_DSW execution failed\n");
362 dev
->wakeup
.flags
.valid
= 0;
368 in_arg
[0].integer
.value
= enable
;
369 status
= acpi_evaluate_object(dev
->handle
, "_PSW", &arg_list
, NULL
);
370 if (ACPI_FAILURE(status
) && (status
!= AE_NOT_FOUND
)) {
371 printk(KERN_ERR PREFIX
"_PSW execution failed\n");
372 dev
->wakeup
.flags
.valid
= 0;
380 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
381 * 1. Power on the power resources required for the wakeup device
382 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
383 * State Wake) for the device, if present
385 int acpi_enable_wakeup_device_power(struct acpi_device
*dev
, int sleep_state
)
389 if (!dev
|| !dev
->wakeup
.flags
.valid
)
393 * Do not execute the code below twice in a row without calling
394 * acpi_disable_wakeup_device_power() in between for the same device
396 if (dev
->wakeup
.flags
.prepared
)
399 /* Open power resource */
400 for (i
= 0; i
< dev
->wakeup
.resources
.count
; i
++) {
401 int ret
= acpi_power_on(dev
->wakeup
.resources
.handles
[i
], dev
);
403 printk(KERN_ERR PREFIX
"Transition power state\n");
404 dev
->wakeup
.flags
.valid
= 0;
410 * Passing 3 as the third argument below means the device may be placed
411 * in arbitrary power state afterwards.
413 err
= acpi_device_sleep_wake(dev
, 1, sleep_state
, 3);
415 dev
->wakeup
.flags
.prepared
= 1;
421 * Shutdown a wakeup device, counterpart of above method
422 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
423 * State Wake) for the device, if present
424 * 2. Shutdown down the power resources
426 int acpi_disable_wakeup_device_power(struct acpi_device
*dev
)
430 if (!dev
|| !dev
->wakeup
.flags
.valid
)
434 * Do not execute the code below twice in a row without calling
435 * acpi_enable_wakeup_device_power() in between for the same device
437 if (!dev
->wakeup
.flags
.prepared
)
440 dev
->wakeup
.flags
.prepared
= 0;
442 ret
= acpi_device_sleep_wake(dev
, 0, 0, 0);
446 /* Close power resource */
447 for (i
= 0; i
< dev
->wakeup
.resources
.count
; i
++) {
448 ret
= acpi_power_off_device(dev
->wakeup
.resources
.handles
[i
], dev
);
450 printk(KERN_ERR PREFIX
"Transition power state\n");
451 dev
->wakeup
.flags
.valid
= 0;
459 /* --------------------------------------------------------------------------
460 Device Power Management
461 -------------------------------------------------------------------------- */
463 int acpi_power_get_inferred_state(struct acpi_device
*device
)
466 struct acpi_handle_list
*list
= NULL
;
474 device
->power
.state
= ACPI_STATE_UNKNOWN
;
477 * We know a device's inferred power state when all the resources
478 * required for a given D-state are 'on'.
480 for (i
= ACPI_STATE_D0
; i
< ACPI_STATE_D3
; i
++) {
481 list
= &device
->power
.states
[i
].resources
;
485 result
= acpi_power_get_list_state(list
, &list_state
);
489 if (list_state
== ACPI_POWER_RESOURCE_STATE_ON
) {
490 device
->power
.state
= i
;
495 device
->power
.state
= ACPI_STATE_D3
;
500 int acpi_power_transition(struct acpi_device
*device
, int state
)
503 struct acpi_handle_list
*cl
= NULL
; /* Current Resources */
504 struct acpi_handle_list
*tl
= NULL
; /* Target Resources */
508 if (!device
|| (state
< ACPI_STATE_D0
) || (state
> ACPI_STATE_D3
))
511 if ((device
->power
.state
< ACPI_STATE_D0
)
512 || (device
->power
.state
> ACPI_STATE_D3
))
515 cl
= &device
->power
.states
[device
->power
.state
].resources
;
516 tl
= &device
->power
.states
[state
].resources
;
518 if (!cl
->count
&& !tl
->count
) {
523 /* TBD: Resources must be ordered. */
526 * First we reference all power resources required in the target list
527 * (e.g. so the device doesn't lose power while transitioning).
529 for (i
= 0; i
< tl
->count
; i
++) {
530 result
= acpi_power_on(tl
->handles
[i
], device
);
535 if (device
->power
.state
== state
) {
540 * Then we dereference all power resources used in the current list.
542 for (i
= 0; i
< cl
->count
; i
++) {
543 result
= acpi_power_off_device(cl
->handles
[i
], device
);
550 device
->power
.state
= ACPI_STATE_UNKNOWN
;
552 /* We shouldn't change the state till all above operations succeed */
553 device
->power
.state
= state
;
559 /* --------------------------------------------------------------------------
561 -------------------------------------------------------------------------- */
563 static struct proc_dir_entry
*acpi_power_dir
;
565 static int acpi_power_seq_show(struct seq_file
*seq
, void *offset
)
568 int result
= 0, state
;
569 struct acpi_power_resource
*resource
= NULL
;
570 struct list_head
*node
, *next
;
571 struct acpi_power_reference
*ref
;
574 resource
= seq
->private;
579 result
= acpi_power_get_state(resource
->device
->handle
, &state
);
583 seq_puts(seq
, "state: ");
585 case ACPI_POWER_RESOURCE_STATE_ON
:
586 seq_puts(seq
, "on\n");
588 case ACPI_POWER_RESOURCE_STATE_OFF
:
589 seq_puts(seq
, "off\n");
592 seq_puts(seq
, "unknown\n");
596 mutex_lock(&resource
->resource_lock
);
597 list_for_each_safe(node
, next
, &resource
->reference
) {
598 ref
= container_of(node
, struct acpi_power_reference
, node
);
601 mutex_unlock(&resource
->resource_lock
);
603 seq_printf(seq
, "system level: S%d\n"
605 "reference count: %d\n",
606 resource
->system_level
,
607 resource
->order
, count
);
613 static int acpi_power_open_fs(struct inode
*inode
, struct file
*file
)
615 return single_open(file
, acpi_power_seq_show
, PDE(inode
)->data
);
618 static int acpi_power_add_fs(struct acpi_device
*device
)
620 struct proc_dir_entry
*entry
= NULL
;
626 if (!acpi_device_dir(device
)) {
627 acpi_device_dir(device
) = proc_mkdir(acpi_device_bid(device
),
629 if (!acpi_device_dir(device
))
634 entry
= proc_create_data(ACPI_POWER_FILE_STATUS
,
635 S_IRUGO
, acpi_device_dir(device
),
636 &acpi_power_fops
, acpi_driver_data(device
));
642 static int acpi_power_remove_fs(struct acpi_device
*device
)
645 if (acpi_device_dir(device
)) {
646 remove_proc_entry(ACPI_POWER_FILE_STATUS
,
647 acpi_device_dir(device
));
648 remove_proc_entry(acpi_device_bid(device
), acpi_power_dir
);
649 acpi_device_dir(device
) = NULL
;
655 /* --------------------------------------------------------------------------
657 -------------------------------------------------------------------------- */
659 static int acpi_power_add(struct acpi_device
*device
)
661 int result
= 0, state
;
662 acpi_status status
= AE_OK
;
663 struct acpi_power_resource
*resource
= NULL
;
664 union acpi_object acpi_object
;
665 struct acpi_buffer buffer
= { sizeof(acpi_object
), &acpi_object
};
671 resource
= kzalloc(sizeof(struct acpi_power_resource
), GFP_KERNEL
);
675 resource
->device
= device
;
676 mutex_init(&resource
->resource_lock
);
677 INIT_LIST_HEAD(&resource
->reference
);
678 strcpy(resource
->name
, device
->pnp
.bus_id
);
679 strcpy(acpi_device_name(device
), ACPI_POWER_DEVICE_NAME
);
680 strcpy(acpi_device_class(device
), ACPI_POWER_CLASS
);
681 device
->driver_data
= resource
;
683 /* Evalute the object to get the system level and resource order. */
684 status
= acpi_evaluate_object(device
->handle
, NULL
, NULL
, &buffer
);
685 if (ACPI_FAILURE(status
)) {
689 resource
->system_level
= acpi_object
.power_resource
.system_level
;
690 resource
->order
= acpi_object
.power_resource
.resource_order
;
692 result
= acpi_power_get_state(device
->handle
, &state
);
697 case ACPI_POWER_RESOURCE_STATE_ON
:
698 device
->power
.state
= ACPI_STATE_D0
;
700 case ACPI_POWER_RESOURCE_STATE_OFF
:
701 device
->power
.state
= ACPI_STATE_D3
;
704 device
->power
.state
= ACPI_STATE_UNKNOWN
;
708 result
= acpi_power_add_fs(device
);
712 printk(KERN_INFO PREFIX
"%s [%s] (%s)\n", acpi_device_name(device
),
713 acpi_device_bid(device
), state
? "on" : "off");
722 static int acpi_power_remove(struct acpi_device
*device
, int type
)
724 struct acpi_power_resource
*resource
= NULL
;
725 struct list_head
*node
, *next
;
728 if (!device
|| !acpi_driver_data(device
))
731 resource
= acpi_driver_data(device
);
733 acpi_power_remove_fs(device
);
735 mutex_lock(&resource
->resource_lock
);
736 list_for_each_safe(node
, next
, &resource
->reference
) {
737 struct acpi_power_reference
*ref
= container_of(node
, struct acpi_power_reference
, node
);
738 list_del(&ref
->node
);
741 mutex_unlock(&resource
->resource_lock
);
748 static int acpi_power_resume(struct acpi_device
*device
)
750 int result
= 0, state
;
751 struct acpi_power_resource
*resource
= NULL
;
752 struct acpi_power_reference
*ref
;
754 if (!device
|| !acpi_driver_data(device
))
757 resource
= acpi_driver_data(device
);
759 result
= acpi_power_get_state(device
->handle
, &state
);
763 mutex_lock(&resource
->resource_lock
);
764 if (state
== ACPI_POWER_RESOURCE_STATE_OFF
&&
765 !list_empty(&resource
->reference
)) {
766 ref
= container_of(resource
->reference
.next
, struct acpi_power_reference
, node
);
767 mutex_unlock(&resource
->resource_lock
);
768 result
= acpi_power_on(device
->handle
, ref
->device
);
772 mutex_unlock(&resource
->resource_lock
);
776 static int __init
acpi_power_init(void)
784 INIT_LIST_HEAD(&acpi_power_resource_list
);
786 acpi_power_dir
= proc_mkdir(ACPI_POWER_CLASS
, acpi_root_dir
);
790 result
= acpi_bus_register_driver(&acpi_power_driver
);
792 remove_proc_entry(ACPI_POWER_CLASS
, acpi_root_dir
);
799 subsys_initcall(acpi_power_init
);