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-rw-r--r--kernel/drivers/acpi/power.c858
1 files changed, 858 insertions, 0 deletions
diff --git a/kernel/drivers/acpi/power.c b/kernel/drivers/acpi/power.c
new file mode 100644
index 000000000..e0bcfb642
--- /dev/null
+++ b/kernel/drivers/acpi/power.c
@@ -0,0 +1,858 @@
+/*
+ * acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
+ *
+ * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+/*
+ * ACPI power-managed devices may be controlled in two ways:
+ * 1. via "Device Specific (D-State) Control"
+ * 2. via "Power Resource Control".
+ * This module is used to manage devices relying on Power Resource Control.
+ *
+ * An ACPI "power resource object" describes a software controllable power
+ * plane, clock plane, or other resource used by a power managed device.
+ * A device may rely on multiple power resources, and a power resource
+ * may be shared by multiple devices.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/sysfs.h>
+#include <linux/acpi.h>
+#include "sleep.h"
+#include "internal.h"
+
+#define _COMPONENT ACPI_POWER_COMPONENT
+ACPI_MODULE_NAME("power");
+#define ACPI_POWER_CLASS "power_resource"
+#define ACPI_POWER_DEVICE_NAME "Power Resource"
+#define ACPI_POWER_FILE_INFO "info"
+#define ACPI_POWER_FILE_STATUS "state"
+#define ACPI_POWER_RESOURCE_STATE_OFF 0x00
+#define ACPI_POWER_RESOURCE_STATE_ON 0x01
+#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
+
+struct acpi_power_resource {
+ struct acpi_device device;
+ struct list_head list_node;
+ char *name;
+ u32 system_level;
+ u32 order;
+ unsigned int ref_count;
+ bool wakeup_enabled;
+ struct mutex resource_lock;
+};
+
+struct acpi_power_resource_entry {
+ struct list_head node;
+ struct acpi_power_resource *resource;
+};
+
+static LIST_HEAD(acpi_power_resource_list);
+static DEFINE_MUTEX(power_resource_list_lock);
+
+/* --------------------------------------------------------------------------
+ Power Resource Management
+ -------------------------------------------------------------------------- */
+
+static inline
+struct acpi_power_resource *to_power_resource(struct acpi_device *device)
+{
+ return container_of(device, struct acpi_power_resource, device);
+}
+
+static struct acpi_power_resource *acpi_power_get_context(acpi_handle handle)
+{
+ struct acpi_device *device;
+
+ if (acpi_bus_get_device(handle, &device))
+ return NULL;
+
+ return to_power_resource(device);
+}
+
+static int acpi_power_resources_list_add(acpi_handle handle,
+ struct list_head *list)
+{
+ struct acpi_power_resource *resource = acpi_power_get_context(handle);
+ struct acpi_power_resource_entry *entry;
+
+ if (!resource || !list)
+ return -EINVAL;
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->resource = resource;
+ if (!list_empty(list)) {
+ struct acpi_power_resource_entry *e;
+
+ list_for_each_entry(e, list, node)
+ if (e->resource->order > resource->order) {
+ list_add_tail(&entry->node, &e->node);
+ return 0;
+ }
+ }
+ list_add_tail(&entry->node, list);
+ return 0;
+}
+
+void acpi_power_resources_list_free(struct list_head *list)
+{
+ struct acpi_power_resource_entry *entry, *e;
+
+ list_for_each_entry_safe(entry, e, list, node) {
+ list_del(&entry->node);
+ kfree(entry);
+ }
+}
+
+int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
+ struct list_head *list)
+{
+ unsigned int i;
+ int err = 0;
+
+ for (i = start; i < package->package.count; i++) {
+ union acpi_object *element = &package->package.elements[i];
+ acpi_handle rhandle;
+
+ if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
+ err = -ENODATA;
+ break;
+ }
+ rhandle = element->reference.handle;
+ if (!rhandle) {
+ err = -ENODEV;
+ break;
+ }
+ err = acpi_add_power_resource(rhandle);
+ if (err)
+ break;
+
+ err = acpi_power_resources_list_add(rhandle, list);
+ if (err)
+ break;
+ }
+ if (err)
+ acpi_power_resources_list_free(list);
+
+ return err;
+}
+
+static int acpi_power_get_state(acpi_handle handle, int *state)
+{
+ acpi_status status = AE_OK;
+ unsigned long long sta = 0;
+ char node_name[5];
+ struct acpi_buffer buffer = { sizeof(node_name), node_name };
+
+
+ if (!handle || !state)
+ return -EINVAL;
+
+ status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
+ ACPI_POWER_RESOURCE_STATE_OFF;
+
+ acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
+ node_name,
+ *state ? "on" : "off"));
+
+ return 0;
+}
+
+static int acpi_power_get_list_state(struct list_head *list, int *state)
+{
+ struct acpi_power_resource_entry *entry;
+ int cur_state;
+
+ if (!list || !state)
+ return -EINVAL;
+
+ /* The state of the list is 'on' IFF all resources are 'on'. */
+ list_for_each_entry(entry, list, node) {
+ struct acpi_power_resource *resource = entry->resource;
+ acpi_handle handle = resource->device.handle;
+ int result;
+
+ mutex_lock(&resource->resource_lock);
+ result = acpi_power_get_state(handle, &cur_state);
+ mutex_unlock(&resource->resource_lock);
+ if (result)
+ return result;
+
+ if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
+ break;
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
+ cur_state ? "on" : "off"));
+
+ *state = cur_state;
+ return 0;
+}
+
+static int __acpi_power_on(struct acpi_power_resource *resource)
+{
+ acpi_status status = AE_OK;
+
+ status = acpi_evaluate_object(resource->device.handle, "_ON", NULL, NULL);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
+ resource->name));
+
+ return 0;
+}
+
+static int acpi_power_on_unlocked(struct acpi_power_resource *resource)
+{
+ int result = 0;
+
+ if (resource->ref_count++) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Power resource [%s] already on\n",
+ resource->name));
+ } else {
+ result = __acpi_power_on(resource);
+ if (result)
+ resource->ref_count--;
+ }
+ return result;
+}
+
+static int acpi_power_on(struct acpi_power_resource *resource)
+{
+ int result;
+
+ mutex_lock(&resource->resource_lock);
+ result = acpi_power_on_unlocked(resource);
+ mutex_unlock(&resource->resource_lock);
+ return result;
+}
+
+static int __acpi_power_off(struct acpi_power_resource *resource)
+{
+ acpi_status status;
+
+ status = acpi_evaluate_object(resource->device.handle, "_OFF",
+ NULL, NULL);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned off\n",
+ resource->name));
+ return 0;
+}
+
+static int acpi_power_off_unlocked(struct acpi_power_resource *resource)
+{
+ int result = 0;
+
+ if (!resource->ref_count) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Power resource [%s] already off\n",
+ resource->name));
+ return 0;
+ }
+
+ if (--resource->ref_count) {
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Power resource [%s] still in use\n",
+ resource->name));
+ } else {
+ result = __acpi_power_off(resource);
+ if (result)
+ resource->ref_count++;
+ }
+ return result;
+}
+
+static int acpi_power_off(struct acpi_power_resource *resource)
+{
+ int result;
+
+ mutex_lock(&resource->resource_lock);
+ result = acpi_power_off_unlocked(resource);
+ mutex_unlock(&resource->resource_lock);
+ return result;
+}
+
+static int acpi_power_off_list(struct list_head *list)
+{
+ struct acpi_power_resource_entry *entry;
+ int result = 0;
+
+ list_for_each_entry_reverse(entry, list, node) {
+ result = acpi_power_off(entry->resource);
+ if (result)
+ goto err;
+ }
+ return 0;
+
+ err:
+ list_for_each_entry_continue(entry, list, node)
+ acpi_power_on(entry->resource);
+
+ return result;
+}
+
+static int acpi_power_on_list(struct list_head *list)
+{
+ struct acpi_power_resource_entry *entry;
+ int result = 0;
+
+ list_for_each_entry(entry, list, node) {
+ result = acpi_power_on(entry->resource);
+ if (result)
+ goto err;
+ }
+ return 0;
+
+ err:
+ list_for_each_entry_continue_reverse(entry, list, node)
+ acpi_power_off(entry->resource);
+
+ return result;
+}
+
+static struct attribute *attrs[] = {
+ NULL,
+};
+
+static struct attribute_group attr_groups[] = {
+ [ACPI_STATE_D0] = {
+ .name = "power_resources_D0",
+ .attrs = attrs,
+ },
+ [ACPI_STATE_D1] = {
+ .name = "power_resources_D1",
+ .attrs = attrs,
+ },
+ [ACPI_STATE_D2] = {
+ .name = "power_resources_D2",
+ .attrs = attrs,
+ },
+ [ACPI_STATE_D3_HOT] = {
+ .name = "power_resources_D3hot",
+ .attrs = attrs,
+ },
+};
+
+static struct attribute_group wakeup_attr_group = {
+ .name = "power_resources_wakeup",
+ .attrs = attrs,
+};
+
+static void acpi_power_hide_list(struct acpi_device *adev,
+ struct list_head *resources,
+ struct attribute_group *attr_group)
+{
+ struct acpi_power_resource_entry *entry;
+
+ if (list_empty(resources))
+ return;
+
+ list_for_each_entry_reverse(entry, resources, node) {
+ struct acpi_device *res_dev = &entry->resource->device;
+
+ sysfs_remove_link_from_group(&adev->dev.kobj,
+ attr_group->name,
+ dev_name(&res_dev->dev));
+ }
+ sysfs_remove_group(&adev->dev.kobj, attr_group);
+}
+
+static void acpi_power_expose_list(struct acpi_device *adev,
+ struct list_head *resources,
+ struct attribute_group *attr_group)
+{
+ struct acpi_power_resource_entry *entry;
+ int ret;
+
+ if (list_empty(resources))
+ return;
+
+ ret = sysfs_create_group(&adev->dev.kobj, attr_group);
+ if (ret)
+ return;
+
+ list_for_each_entry(entry, resources, node) {
+ struct acpi_device *res_dev = &entry->resource->device;
+
+ ret = sysfs_add_link_to_group(&adev->dev.kobj,
+ attr_group->name,
+ &res_dev->dev.kobj,
+ dev_name(&res_dev->dev));
+ if (ret) {
+ acpi_power_hide_list(adev, resources, attr_group);
+ break;
+ }
+ }
+}
+
+static void acpi_power_expose_hide(struct acpi_device *adev,
+ struct list_head *resources,
+ struct attribute_group *attr_group,
+ bool expose)
+{
+ if (expose)
+ acpi_power_expose_list(adev, resources, attr_group);
+ else
+ acpi_power_hide_list(adev, resources, attr_group);
+}
+
+void acpi_power_add_remove_device(struct acpi_device *adev, bool add)
+{
+ int state;
+
+ if (adev->wakeup.flags.valid)
+ acpi_power_expose_hide(adev, &adev->wakeup.resources,
+ &wakeup_attr_group, add);
+
+ if (!adev->power.flags.power_resources)
+ return;
+
+ for (state = ACPI_STATE_D0; state <= ACPI_STATE_D3_HOT; state++)
+ acpi_power_expose_hide(adev,
+ &adev->power.states[state].resources,
+ &attr_groups[state], add);
+}
+
+int acpi_power_wakeup_list_init(struct list_head *list, int *system_level_p)
+{
+ struct acpi_power_resource_entry *entry;
+ int system_level = 5;
+
+ list_for_each_entry(entry, list, node) {
+ struct acpi_power_resource *resource = entry->resource;
+ acpi_handle handle = resource->device.handle;
+ int result;
+ int state;
+
+ mutex_lock(&resource->resource_lock);
+
+ result = acpi_power_get_state(handle, &state);
+ if (result) {
+ mutex_unlock(&resource->resource_lock);
+ return result;
+ }
+ if (state == ACPI_POWER_RESOURCE_STATE_ON) {
+ resource->ref_count++;
+ resource->wakeup_enabled = true;
+ }
+ if (system_level > resource->system_level)
+ system_level = resource->system_level;
+
+ mutex_unlock(&resource->resource_lock);
+ }
+ *system_level_p = system_level;
+ return 0;
+}
+
+/* --------------------------------------------------------------------------
+ Device Power Management
+ -------------------------------------------------------------------------- */
+
+/**
+ * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
+ * ACPI 3.0) _PSW (Power State Wake)
+ * @dev: Device to handle.
+ * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
+ * @sleep_state: Target sleep state of the system.
+ * @dev_state: Target power state of the device.
+ *
+ * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
+ * State Wake) for the device, if present. On failure reset the device's
+ * wakeup.flags.valid flag.
+ *
+ * RETURN VALUE:
+ * 0 if either _DSW or _PSW has been successfully executed
+ * 0 if neither _DSW nor _PSW has been found
+ * -ENODEV if the execution of either _DSW or _PSW has failed
+ */
+int acpi_device_sleep_wake(struct acpi_device *dev,
+ int enable, int sleep_state, int dev_state)
+{
+ union acpi_object in_arg[3];
+ struct acpi_object_list arg_list = { 3, in_arg };
+ acpi_status status = AE_OK;
+
+ /*
+ * Try to execute _DSW first.
+ *
+ * Three agruments are needed for the _DSW object:
+ * Argument 0: enable/disable the wake capabilities
+ * Argument 1: target system state
+ * Argument 2: target device state
+ * When _DSW object is called to disable the wake capabilities, maybe
+ * the first argument is filled. The values of the other two agruments
+ * are meaningless.
+ */
+ in_arg[0].type = ACPI_TYPE_INTEGER;
+ in_arg[0].integer.value = enable;
+ in_arg[1].type = ACPI_TYPE_INTEGER;
+ in_arg[1].integer.value = sleep_state;
+ in_arg[2].type = ACPI_TYPE_INTEGER;
+ in_arg[2].integer.value = dev_state;
+ status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
+ if (ACPI_SUCCESS(status)) {
+ return 0;
+ } else if (status != AE_NOT_FOUND) {
+ printk(KERN_ERR PREFIX "_DSW execution failed\n");
+ dev->wakeup.flags.valid = 0;
+ return -ENODEV;
+ }
+
+ /* Execute _PSW */
+ status = acpi_execute_simple_method(dev->handle, "_PSW", enable);
+ if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
+ printk(KERN_ERR PREFIX "_PSW execution failed\n");
+ dev->wakeup.flags.valid = 0;
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+/*
+ * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
+ * 1. Power on the power resources required for the wakeup device
+ * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
+ * State Wake) for the device, if present
+ */
+int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
+{
+ struct acpi_power_resource_entry *entry;
+ int err = 0;
+
+ if (!dev || !dev->wakeup.flags.valid)
+ return -EINVAL;
+
+ mutex_lock(&acpi_device_lock);
+
+ if (dev->wakeup.prepare_count++)
+ goto out;
+
+ list_for_each_entry(entry, &dev->wakeup.resources, node) {
+ struct acpi_power_resource *resource = entry->resource;
+
+ mutex_lock(&resource->resource_lock);
+
+ if (!resource->wakeup_enabled) {
+ err = acpi_power_on_unlocked(resource);
+ if (!err)
+ resource->wakeup_enabled = true;
+ }
+
+ mutex_unlock(&resource->resource_lock);
+
+ if (err) {
+ dev_err(&dev->dev,
+ "Cannot turn wakeup power resources on\n");
+ dev->wakeup.flags.valid = 0;
+ goto out;
+ }
+ }
+ /*
+ * Passing 3 as the third argument below means the device may be
+ * put into arbitrary power state afterward.
+ */
+ err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
+ if (err)
+ dev->wakeup.prepare_count = 0;
+
+ out:
+ mutex_unlock(&acpi_device_lock);
+ return err;
+}
+
+/*
+ * Shutdown a wakeup device, counterpart of above method
+ * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
+ * State Wake) for the device, if present
+ * 2. Shutdown down the power resources
+ */
+int acpi_disable_wakeup_device_power(struct acpi_device *dev)
+{
+ struct acpi_power_resource_entry *entry;
+ int err = 0;
+
+ if (!dev || !dev->wakeup.flags.valid)
+ return -EINVAL;
+
+ mutex_lock(&acpi_device_lock);
+
+ if (--dev->wakeup.prepare_count > 0)
+ goto out;
+
+ /*
+ * Executing the code below even if prepare_count is already zero when
+ * the function is called may be useful, for example for initialisation.
+ */
+ if (dev->wakeup.prepare_count < 0)
+ dev->wakeup.prepare_count = 0;
+
+ err = acpi_device_sleep_wake(dev, 0, 0, 0);
+ if (err)
+ goto out;
+
+ list_for_each_entry(entry, &dev->wakeup.resources, node) {
+ struct acpi_power_resource *resource = entry->resource;
+
+ mutex_lock(&resource->resource_lock);
+
+ if (resource->wakeup_enabled) {
+ err = acpi_power_off_unlocked(resource);
+ if (!err)
+ resource->wakeup_enabled = false;
+ }
+
+ mutex_unlock(&resource->resource_lock);
+
+ if (err) {
+ dev_err(&dev->dev,
+ "Cannot turn wakeup power resources off\n");
+ dev->wakeup.flags.valid = 0;
+ break;
+ }
+ }
+
+ out:
+ mutex_unlock(&acpi_device_lock);
+ return err;
+}
+
+int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
+{
+ int result = 0;
+ int list_state = 0;
+ int i = 0;
+
+ if (!device || !state)
+ return -EINVAL;
+
+ /*
+ * We know a device's inferred power state when all the resources
+ * required for a given D-state are 'on'.
+ */
+ for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
+ struct list_head *list = &device->power.states[i].resources;
+
+ if (list_empty(list))
+ continue;
+
+ result = acpi_power_get_list_state(list, &list_state);
+ if (result)
+ return result;
+
+ if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
+ *state = i;
+ return 0;
+ }
+ }
+
+ *state = ACPI_STATE_D3_COLD;
+ return 0;
+}
+
+int acpi_power_on_resources(struct acpi_device *device, int state)
+{
+ if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3_HOT)
+ return -EINVAL;
+
+ return acpi_power_on_list(&device->power.states[state].resources);
+}
+
+int acpi_power_transition(struct acpi_device *device, int state)
+{
+ int result = 0;
+
+ if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
+ return -EINVAL;
+
+ if (device->power.state == state || !device->flags.power_manageable)
+ return 0;
+
+ if ((device->power.state < ACPI_STATE_D0)
+ || (device->power.state > ACPI_STATE_D3_COLD))
+ return -ENODEV;
+
+ /* TBD: Resources must be ordered. */
+
+ /*
+ * First we reference all power resources required in the target list
+ * (e.g. so the device doesn't lose power while transitioning). Then,
+ * we dereference all power resources used in the current list.
+ */
+ if (state < ACPI_STATE_D3_COLD)
+ result = acpi_power_on_list(
+ &device->power.states[state].resources);
+
+ if (!result && device->power.state < ACPI_STATE_D3_COLD)
+ acpi_power_off_list(
+ &device->power.states[device->power.state].resources);
+
+ /* We shouldn't change the state unless the above operations succeed. */
+ device->power.state = result ? ACPI_STATE_UNKNOWN : state;
+
+ return result;
+}
+
+static void acpi_release_power_resource(struct device *dev)
+{
+ struct acpi_device *device = to_acpi_device(dev);
+ struct acpi_power_resource *resource;
+
+ resource = container_of(device, struct acpi_power_resource, device);
+
+ mutex_lock(&power_resource_list_lock);
+ list_del(&resource->list_node);
+ mutex_unlock(&power_resource_list_lock);
+
+ acpi_free_pnp_ids(&device->pnp);
+ kfree(resource);
+}
+
+static ssize_t acpi_power_in_use_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf) {
+ struct acpi_power_resource *resource;
+
+ resource = to_power_resource(to_acpi_device(dev));
+ return sprintf(buf, "%u\n", !!resource->ref_count);
+}
+static DEVICE_ATTR(resource_in_use, 0444, acpi_power_in_use_show, NULL);
+
+static void acpi_power_sysfs_remove(struct acpi_device *device)
+{
+ device_remove_file(&device->dev, &dev_attr_resource_in_use);
+}
+
+int acpi_add_power_resource(acpi_handle handle)
+{
+ struct acpi_power_resource *resource;
+ struct acpi_device *device = NULL;
+ union acpi_object acpi_object;
+ struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
+ acpi_status status;
+ int state, result = -ENODEV;
+
+ acpi_bus_get_device(handle, &device);
+ if (device)
+ return 0;
+
+ resource = kzalloc(sizeof(*resource), GFP_KERNEL);
+ if (!resource)
+ return -ENOMEM;
+
+ device = &resource->device;
+ acpi_init_device_object(device, handle, ACPI_BUS_TYPE_POWER,
+ ACPI_STA_DEFAULT);
+ mutex_init(&resource->resource_lock);
+ INIT_LIST_HEAD(&resource->list_node);
+ resource->name = device->pnp.bus_id;
+ strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
+ strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
+ device->power.state = ACPI_STATE_UNKNOWN;
+
+ /* Evalute the object to get the system level and resource order. */
+ status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
+ if (ACPI_FAILURE(status))
+ goto err;
+
+ resource->system_level = acpi_object.power_resource.system_level;
+ resource->order = acpi_object.power_resource.resource_order;
+
+ result = acpi_power_get_state(handle, &state);
+ if (result)
+ goto err;
+
+ printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
+ acpi_device_bid(device), state ? "on" : "off");
+
+ device->flags.match_driver = true;
+ result = acpi_device_add(device, acpi_release_power_resource);
+ if (result)
+ goto err;
+
+ if (!device_create_file(&device->dev, &dev_attr_resource_in_use))
+ device->remove = acpi_power_sysfs_remove;
+
+ mutex_lock(&power_resource_list_lock);
+ list_add(&resource->list_node, &acpi_power_resource_list);
+ mutex_unlock(&power_resource_list_lock);
+ acpi_device_add_finalize(device);
+ return 0;
+
+ err:
+ acpi_release_power_resource(&device->dev);
+ return result;
+}
+
+#ifdef CONFIG_ACPI_SLEEP
+void acpi_resume_power_resources(void)
+{
+ struct acpi_power_resource *resource;
+
+ mutex_lock(&power_resource_list_lock);
+
+ list_for_each_entry(resource, &acpi_power_resource_list, list_node) {
+ int result, state;
+
+ mutex_lock(&resource->resource_lock);
+
+ result = acpi_power_get_state(resource->device.handle, &state);
+ if (result) {
+ mutex_unlock(&resource->resource_lock);
+ continue;
+ }
+
+ if (state == ACPI_POWER_RESOURCE_STATE_OFF
+ && resource->ref_count) {
+ dev_info(&resource->device.dev, "Turning ON\n");
+ __acpi_power_on(resource);
+ } else if (state == ACPI_POWER_RESOURCE_STATE_ON
+ && !resource->ref_count) {
+ dev_info(&resource->device.dev, "Turning OFF\n");
+ __acpi_power_off(resource);
+ }
+
+ mutex_unlock(&resource->resource_lock);
+ }
+
+ mutex_unlock(&power_resource_list_lock);
+}
+#endif