+static void __acpi_power_resource_unregister_device(struct device *dev,
+ acpi_handle res_handle)
+{
+ struct acpi_power_resource *resource = NULL;
+ struct acpi_power_resource_device *prev, *curr;
+
+ if (acpi_power_get_context(res_handle, &resource))
+ return;
+
+ mutex_lock(&resource->resource_lock);
+ prev = NULL;
+ curr = resource->devices;
+ while (curr) {
+ if (curr->device->dev == dev) {
+ if (!prev)
+ resource->devices = curr->next;
+ else
+ prev->next = curr->next;
+
+ kfree(curr);
+ break;
+ }
+
+ prev = curr;
+ curr = curr->next;
+ }
+ mutex_unlock(&resource->resource_lock);
+}
+
+/* Unlink dev from all power resources in _PR0 */
+void acpi_power_resource_unregister_device(struct device *dev, acpi_handle handle)
+{
+ struct acpi_device *acpi_dev;
+ struct acpi_handle_list *list;
+ int i;
+
+ if (!dev || !handle)
+ return;
+
+ if (acpi_bus_get_device(handle, &acpi_dev))
+ return;
+
+ list = &acpi_dev->power.states[ACPI_STATE_D0].resources;
+
+ for (i = 0; i < list->count; i++)
+ __acpi_power_resource_unregister_device(dev,
+ list->handles[i]);
+}
+
+static int __acpi_power_resource_register_device(
+ struct acpi_power_managed_device *powered_device, acpi_handle handle)
+{
+ struct acpi_power_resource *resource = NULL;
+ struct acpi_power_resource_device *power_resource_device;
+ int result;
+
+ result = acpi_power_get_context(handle, &resource);
+ if (result)
+ return result;
+
+ power_resource_device = kzalloc(
+ sizeof(*power_resource_device), GFP_KERNEL);
+ if (!power_resource_device)
+ return -ENOMEM;
+
+ power_resource_device->device = powered_device;
+
+ mutex_lock(&resource->resource_lock);
+ power_resource_device->next = resource->devices;
+ resource->devices = power_resource_device;
+ mutex_unlock(&resource->resource_lock);
+
+ return 0;
+}
+
+/* Link dev to all power resources in _PR0 */
+int acpi_power_resource_register_device(struct device *dev, acpi_handle handle)
+{
+ struct acpi_device *acpi_dev;
+ struct acpi_handle_list *list;
+ struct acpi_power_managed_device *powered_device;
+ int i, ret;
+
+ if (!dev || !handle)
+ return -ENODEV;
+
+ ret = acpi_bus_get_device(handle, &acpi_dev);
+ if (ret)
+ goto no_power_resource;
+
+ if (!acpi_dev->power.flags.power_resources)
+ goto no_power_resource;
+
+ powered_device = kzalloc(sizeof(*powered_device), GFP_KERNEL);
+ if (!powered_device)
+ return -ENOMEM;
+
+ powered_device->dev = dev;
+ powered_device->handle = handle;
+
+ list = &acpi_dev->power.states[ACPI_STATE_D0].resources;
+
+ for (i = 0; i < list->count; i++) {
+ ret = __acpi_power_resource_register_device(powered_device,
+ list->handles[i]);
+
+ if (ret) {
+ acpi_power_resource_unregister_device(dev, handle);
+ break;
+ }
+ }
+
+ return ret;
+
+no_power_resource:
+ printk(KERN_WARNING PREFIX "Invalid Power Resource to register!");
+ return -ENODEV;
+}
+