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_dependent_device {
63 struct list_head node;
64 struct acpi_device *adev;
65 struct work_struct work;
68 struct acpi_power_resource {
69 struct acpi_device device;
70 struct list_head list_node;
71 struct list_head dependent;
75 unsigned int ref_count;
77 struct mutex resource_lock;
80 struct acpi_power_resource_entry {
81 struct list_head node;
82 struct acpi_power_resource *resource;
85 static LIST_HEAD(acpi_power_resource_list);
86 static DEFINE_MUTEX(power_resource_list_lock);
88 /* --------------------------------------------------------------------------
89 Power Resource Management
90 -------------------------------------------------------------------------- */
93 struct acpi_power_resource *to_power_resource(struct acpi_device *device)
95 return container_of(device, struct acpi_power_resource, device);
98 static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
100 struct acpi_device *device;
102 if (acpi_bus_get_device(handle, &device))
105 return to_power_resource(device);
108 static int acpi_power_resources_list_add(acpi_handle handle,
109 struct list_head *list)
111 struct acpi_power_resource *resource = acpi_power_get_context(handle);
112 struct acpi_power_resource_entry *entry;
114 if (!resource || !list)
117 entry = kzalloc(sizeof(*entry), GFP_KERNEL);
121 entry->resource = resource;
122 if (!list_empty(list)) {
123 struct acpi_power_resource_entry *e;
125 list_for_each_entry(e, list, node)
126 if (e->resource->order > resource->order) {
127 list_add_tail(&entry->node, &e->node);
131 list_add_tail(&entry->node, list);
135 void acpi_power_resources_list_free(struct list_head *list)
137 struct acpi_power_resource_entry *entry, *e;
139 list_for_each_entry_safe(entry, e, list, node) {
140 list_del(&entry->node);
145 int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
146 struct list_head *list)
151 for (i = start; i < package->package.count; i++) {
152 union acpi_object *element = &package->package.elements[i];
155 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
159 rhandle = element->reference.handle;
164 err = acpi_add_power_resource(rhandle);
168 err = acpi_power_resources_list_add(rhandle, list);
173 acpi_power_resources_list_free(list);
178 static int acpi_power_get_state(acpi_handle handle, int *state)
180 acpi_status status = AE_OK;
181 unsigned long long sta = 0;
183 struct acpi_buffer buffer = { sizeof(node_name), node_name };
186 if (!handle || !state)
189 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
190 if (ACPI_FAILURE(status))
193 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
194 ACPI_POWER_RESOURCE_STATE_OFF;
196 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
198 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
200 *state ? "on" : "off"));
205 static int acpi_power_get_list_state(struct list_head *list, int *state)
207 struct acpi_power_resource_entry *entry;
213 /* The state of the list is 'on' IFF all resources are 'on'. */
214 list_for_each_entry(entry, list, node) {
215 struct acpi_power_resource *resource = entry->resource;
216 acpi_handle handle = resource->device.handle;
219 mutex_lock(&resource->resource_lock);
220 result = acpi_power_get_state(handle, &cur_state);
221 mutex_unlock(&resource->resource_lock);
225 if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
229 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
230 cur_state ? "on" : "off"));
236 static void acpi_power_resume_dependent(struct work_struct *work)
238 struct acpi_power_dependent_device *dep;
239 struct acpi_device_physical_node *pn;
240 struct acpi_device *adev;
243 dep = container_of(work, struct acpi_power_dependent_device, work);
245 if (acpi_power_get_inferred_state(adev, &state))
248 if (state > ACPI_STATE_D0)
251 mutex_lock(&adev->physical_node_lock);
253 list_for_each_entry(pn, &adev->physical_node_list, node)
254 pm_request_resume(pn->dev);
256 list_for_each_entry(pn, &adev->power_dependent, node)
257 pm_request_resume(pn->dev);
259 mutex_unlock(&adev->physical_node_lock);
262 static int __acpi_power_on(struct acpi_power_resource *resource)
264 acpi_status status = AE_OK;
266 status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL);
267 if (ACPI_FAILURE(status))
270 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
276 static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
280 if (resource->ref_count++) {
281 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
282 "Power resource [%s] already on\n",
285 result = __acpi_power_on(resource);
287 resource->ref_count--;
289 struct acpi_power_dependent_device *dep;
291 list_for_each_entry(dep, &resource->dependent, node)
292 schedule_work(&dep->work);
298 static int acpi_power_on(struct acpi_power_resource *resource)
302 mutex_lock(&resource->resource_lock);
303 result = acpi_power_on_unlocked(resource);
304 mutex_unlock(&resource->resource_lock);
308 static int __acpi_power_off(struct acpi_power_resource *resource)
312 status = acpi_evaluate_object(resource->device.handle, "_OFF",
314 if (ACPI_FAILURE(status))
317 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned off\n",
322 static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
326 if (!resource->ref_count) {
327 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
328 "Power resource [%s] already off\n",
333 if (--resource->ref_count) {
334 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
335 "Power resource [%s] still in use\n",
338 result = __acpi_power_off(resource);
340 resource->ref_count++;
345 static int acpi_power_off(struct acpi_power_resource *resource)
349 mutex_lock(&resource->resource_lock);
350 result = acpi_power_off_unlocked(resource);
351 mutex_unlock(&resource->resource_lock);
355 static int acpi_power_off_list(struct list_head *list)
357 struct acpi_power_resource_entry *entry;
360 list_for_each_entry_reverse(entry, list, node) {
361 result = acpi_power_off(entry->resource);
368 list_for_each_entry_continue(entry, list, node)
369 acpi_power_on(entry->resource);
374 static int acpi_power_on_list(struct list_head *list)
376 struct acpi_power_resource_entry *entry;
379 list_for_each_entry(entry, list, node) {
380 result = acpi_power_on(entry->resource);
387 list_for_each_entry_continue_reverse(entry, list, node)
388 acpi_power_off(entry->resource);
393 static void acpi_power_add_dependent(struct acpi_power_resource *resource,
394 struct acpi_device *adev)
396 struct acpi_power_dependent_device *dep;
398 mutex_lock(&resource->resource_lock);
400 list_for_each_entry(dep, &resource->dependent, node)
401 if (dep->adev == adev)
404 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
409 INIT_WORK(&dep->work, acpi_power_resume_dependent);
410 list_add_tail(&dep->node, &resource->dependent);
413 mutex_unlock(&resource->resource_lock);
416 static void acpi_power_remove_dependent(struct acpi_power_resource *resource,
417 struct acpi_device *adev)
419 struct acpi_power_dependent_device *dep;
420 struct work_struct *work = NULL;
422 mutex_lock(&resource->resource_lock);
424 list_for_each_entry(dep, &resource->dependent, node)
425 if (dep->adev == adev) {
426 list_del(&dep->node);
431 mutex_unlock(&resource->resource_lock);
434 cancel_work_sync(work);
439 static struct attribute *attrs[] = {
443 static struct attribute_group attr_groups[] = {
445 .name = "power_resources_D0",
449 .name = "power_resources_D1",
453 .name = "power_resources_D2",
456 [ACPI_STATE_D3_HOT] = {
457 .name = "power_resources_D3hot",
462 static struct attribute_group wakeup_attr_group = {
463 .name = "power_resources_wakeup",
467 static void acpi_power_hide_list(struct acpi_device *adev,
468 struct list_head *resources,
469 struct attribute_group *attr_group)
471 struct acpi_power_resource_entry *entry;
473 if (list_empty(resources))
476 list_for_each_entry_reverse(entry, resources, node) {
477 struct acpi_device *res_dev = &entry->resource->device;
479 sysfs_remove_link_from_group(&adev->dev.kobj,
481 dev_name(&res_dev->dev));
483 sysfs_remove_group(&adev->dev.kobj, attr_group);
486 static void acpi_power_expose_list(struct acpi_device *adev,
487 struct list_head *resources,
488 struct attribute_group *attr_group)
490 struct acpi_power_resource_entry *entry;
493 if (list_empty(resources))
496 ret = sysfs_create_group(&adev->dev.kobj, attr_group);
500 list_for_each_entry(entry, resources, node) {
501 struct acpi_device *res_dev = &entry->resource->device;
503 ret = sysfs_add_link_to_group(&adev->dev.kobj,
506 dev_name(&res_dev->dev));
508 acpi_power_hide_list(adev, resources, attr_group);
514 static void acpi_power_expose_hide(struct acpi_device *adev,
515 struct list_head *resources,
516 struct attribute_group *attr_group,
520 acpi_power_expose_list(adev, resources, attr_group);
522 acpi_power_hide_list(adev, resources, attr_group);
525 void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
527 struct acpi_device_power_state *ps;
528 struct acpi_power_resource_entry *entry;
531 if (adev->wakeup.flags.valid)
532 acpi_power_expose_hide(adev, &adev->wakeup.resources,
533 &wakeup_attr_group, add);
535 if (!adev->power.flags.power_resources)
538 ps = &adev->power.states[ACPI_STATE_D0];
539 list_for_each_entry(entry, &ps->resources, node) {
540 struct acpi_power_resource *resource = entry->resource;
543 acpi_power_add_dependent(resource, adev);
545 acpi_power_remove_dependent(resource, adev);
548 for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
549 acpi_power_expose_hide(adev,
550 &adev->power.states[state].resources,
551 &attr_groups[state], add);
554 int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
556 struct acpi_power_resource_entry *entry;
557 int system_level = 5;
559 list_for_each_entry(entry, list, node) {
560 struct acpi_power_resource *resource = entry->resource;
561 acpi_handle handle = resource->device.handle;
565 mutex_lock(&resource->resource_lock);
567 result = acpi_power_get_state(handle, &state);
569 mutex_unlock(&resource->resource_lock);
572 if (state == ACPI_POWER_RESOURCE_STATE_ON) {
573 resource->ref_count++;
574 resource->wakeup_enabled = true;
576 if (system_level > resource->system_level)
577 system_level = resource->system_level;
579 mutex_unlock(&resource->resource_lock);
581 *system_level_p = system_level;
585 /* --------------------------------------------------------------------------
586 Device Power Management
587 -------------------------------------------------------------------------- */
590 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
591 * ACPI 3.0) _PSW (Power State Wake)
592 * @dev: Device to handle.
593 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
594 * @sleep_state: Target sleep state of the system.
595 * @dev_state: Target power state of the device.
597 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
598 * State Wake) for the device, if present. On failure reset the device's
599 * wakeup.flags.valid flag.
602 * 0 if either _DSW or _PSW has been successfully executed
603 * 0 if neither _DSW nor _PSW has been found
604 * -ENODEV if the execution of either _DSW or _PSW has failed
606 int acpi_device_sleep_wake(struct acpi_device *dev,
607 int enable, int sleep_state, int dev_state)
609 union acpi_object in_arg[3];
610 struct acpi_object_list arg_list = { 3, in_arg };
611 acpi_status status = AE_OK;
614 * Try to execute _DSW first.
616 * Three agruments are needed for the _DSW object:
617 * Argument 0: enable/disable the wake capabilities
618 * Argument 1: target system state
619 * Argument 2: target device state
620 * When _DSW object is called to disable the wake capabilities, maybe
621 * the first argument is filled. The values of the other two agruments
624 in_arg[0].type = ACPI_TYPE_INTEGER;
625 in_arg[0].integer.value = enable;
626 in_arg[1].type = ACPI_TYPE_INTEGER;
627 in_arg[1].integer.value = sleep_state;
628 in_arg[2].type = ACPI_TYPE_INTEGER;
629 in_arg[2].integer.value = dev_state;
630 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
631 if (ACPI_SUCCESS(status)) {
633 } else if (status != AE_NOT_FOUND) {
634 printk(KERN_ERR PREFIX "_DSW execution failed\n");
635 dev->wakeup.flags.valid = 0;
641 in_arg[0].integer.value = enable;
642 status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
643 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
644 printk(KERN_ERR PREFIX "_PSW execution failed\n");
645 dev->wakeup.flags.valid = 0;
653 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
654 * 1. Power on the power resources required for the wakeup device
655 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
656 * State Wake) for the device, if present
658 int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
660 struct acpi_power_resource_entry *entry;
663 if (!dev || !dev->wakeup.flags.valid)
666 mutex_lock(&acpi_device_lock);
668 if (dev->wakeup.prepare_count++)
671 list_for_each_entry(entry, &dev->wakeup.resources, node) {
672 struct acpi_power_resource *resource = entry->resource;
674 mutex_lock(&resource->resource_lock);
676 if (!resource->wakeup_enabled) {
677 err = acpi_power_on_unlocked(resource);
679 resource->wakeup_enabled = true;
682 mutex_unlock(&resource->resource_lock);
686 "Cannot turn wakeup power resources on\n");
687 dev->wakeup.flags.valid = 0;
692 * Passing 3 as the third argument below means the device may be
693 * put into arbitrary power state afterward.
695 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
697 dev->wakeup.prepare_count = 0;
700 mutex_unlock(&acpi_device_lock);
705 * Shutdown a wakeup device, counterpart of above method
706 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
707 * State Wake) for the device, if present
708 * 2. Shutdown down the power resources
710 int acpi_disable_wakeup_device_power(struct acpi_device *dev)
712 struct acpi_power_resource_entry *entry;
715 if (!dev || !dev->wakeup.flags.valid)
718 mutex_lock(&acpi_device_lock);
720 if (--dev->wakeup.prepare_count > 0)
724 * Executing the code below even if prepare_count is already zero when
725 * the function is called may be useful, for example for initialisation.
727 if (dev->wakeup.prepare_count < 0)
728 dev->wakeup.prepare_count = 0;
730 err = acpi_device_sleep_wake(dev, 0, 0, 0);
734 list_for_each_entry(entry, &dev->wakeup.resources, node) {
735 struct acpi_power_resource *resource = entry->resource;
737 mutex_lock(&resource->resource_lock);
739 if (resource->wakeup_enabled) {
740 err = acpi_power_off_unlocked(resource);
742 resource->wakeup_enabled = false;
745 mutex_unlock(&resource->resource_lock);
749 "Cannot turn wakeup power resources off\n");
750 dev->wakeup.flags.valid = 0;
756 mutex_unlock(&acpi_device_lock);
760 int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
766 if (!device || !state)
770 * We know a device's inferred power state when all the resources
771 * required for a given D-state are 'on'.
773 for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
774 struct list_head *list = &device->power.states[i].resources;
776 if (list_empty(list))
779 result = acpi_power_get_list_state(list, &list_state);
783 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
789 *state = ACPI_STATE_D3;
793 int acpi_power_on_resources(struct acpi_device *device, int state)
795 if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
798 return acpi_power_on_list(&device->power.states[state].resources);
801 int acpi_power_transition(struct acpi_device *device, int state)
805 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
808 if (device->power.state == state || !device->flags.power_manageable)
811 if ((device->power.state < ACPI_STATE_D0)
812 || (device->power.state > ACPI_STATE_D3_COLD))
815 /* TBD: Resources must be ordered. */
818 * First we reference all power resources required in the target list
819 * (e.g. so the device doesn't lose power while transitioning). Then,
820 * we dereference all power resources used in the current list.
822 if (state < ACPI_STATE_D3_COLD)
823 result = acpi_power_on_list(
824 &device->power.states[state].resources);
826 if (!result && device->power.state < ACPI_STATE_D3_COLD)
828 &device->power.states[device->power.state].resources);
830 /* We shouldn't change the state unless the above operations succeed. */
831 device->power.state = result ? ACPI_STATE_UNKNOWN : state;
836 static void acpi_release_power_resource(struct device *dev)
838 struct acpi_device *device = to_acpi_device(dev);
839 struct acpi_power_resource *resource;
841 resource = container_of(device, struct acpi_power_resource, device);
843 mutex_lock(&power_resource_list_lock);
844 list_del(&resource->list_node);
845 mutex_unlock(&power_resource_list_lock);
847 acpi_free_pnp_ids(&device->pnp);
851 static ssize_t acpi_power_in_use_show(struct device *dev,
852 struct device_attribute *attr,
854 struct acpi_power_resource *resource;
856 resource = to_power_resource(to_acpi_device(dev));
857 return sprintf(buf, "%u\n", !!resource->ref_count);
859 static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
861 static void acpi_power_sysfs_remove(struct acpi_device *device)
863 device_remove_file(&device->dev, &dev_attr_resource_in_use);
866 int acpi_add_power_resource(acpi_handle handle)
868 struct acpi_power_resource *resource;
869 struct acpi_device *device = NULL;
870 union acpi_object acpi_object;
871 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
873 int state, result = -ENODEV;
875 acpi_bus_get_device(handle, &device);
879 resource = kzalloc(sizeof(*resource), GFP_KERNEL);
883 device = &resource->device;
884 acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
886 mutex_init(&resource->resource_lock);
887 INIT_LIST_HEAD(&resource->dependent);
888 INIT_LIST_HEAD(&resource->list_node);
889 resource->name = device->pnp.bus_id;
890 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
891 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
892 device->power.state = ACPI_STATE_UNKNOWN;
894 /* Evalute the object to get the system level and resource order. */
895 status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
896 if (ACPI_FAILURE(status))
899 resource->system_level = acpi_object.power_resource.system_level;
900 resource->order = acpi_object.power_resource.resource_order;
902 result = acpi_power_get_state(handle, &state);
906 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
907 acpi_device_bid(device), state ? "on" : "off");
909 device->flags.match_driver = true;
910 result = acpi_device_add(device, acpi_release_power_resource);
914 if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
915 device->remove = acpi_power_sysfs_remove;
917 mutex_lock(&power_resource_list_lock);
918 list_add(&resource->list_node, &acpi_power_resource_list);
919 mutex_unlock(&power_resource_list_lock);
920 acpi_device_add_finalize(device);
924 acpi_release_power_resource(&device->dev);
928 #ifdef CONFIG_ACPI_SLEEP
929 void acpi_resume_power_resources(void)
931 struct acpi_power_resource *resource;
933 mutex_lock(&power_resource_list_lock);
935 list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
938 mutex_lock(&resource->resource_lock);
940 result = acpi_power_get_state(resource->device.handle, &state);
944 if (state == ACPI_POWER_RESOURCE_STATE_OFF
945 && resource->ref_count) {
946 dev_info(&resource->device.dev, "Turning ON\n");
947 __acpi_power_on(resource);
948 } else if (state == ACPI_POWER_RESOURCE_STATE_ON
949 && !resource->ref_count) {
950 dev_info(&resource->device.dev, "Turning OFF\n");
951 __acpi_power_off(resource);
954 mutex_unlock(&resource->resource_lock);
957 mutex_unlock(&power_resource_list_lock);