[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/drivers/acpi/scan.c b/ap/os/linux/linux-3.4.x/drivers/acpi/scan.c
new file mode 100644
index 0000000..619a2e4
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/drivers/acpi/scan.c
@@ -0,0 +1,1618 @@
+/*
+ * scan.c - support for transforming the ACPI namespace into individual objects
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/signal.h>
+#include <linux/kthread.h>
+#include <linux/dmi.h>
+
+#include <acpi/acpi_drivers.h>
+
+#include "internal.h"
+
+#define _COMPONENT		ACPI_BUS_COMPONENT
+ACPI_MODULE_NAME("scan");
+#define STRUCT_TO_INT(s)	(*((int*)&s))
+extern struct acpi_device *acpi_root;
+
+#define ACPI_BUS_CLASS			"system_bus"
+#define ACPI_BUS_HID			"LNXSYBUS"
+#define ACPI_BUS_DEVICE_NAME		"System Bus"
+
+#define ACPI_IS_ROOT_DEVICE(device)    (!(device)->parent)
+
+static const char *dummy_hid = "device";
+
+static LIST_HEAD(acpi_device_list);
+static LIST_HEAD(acpi_bus_id_list);
+DEFINE_MUTEX(acpi_device_lock);
+LIST_HEAD(acpi_wakeup_device_list);
+
+struct acpi_device_bus_id{
+	char bus_id[15];
+	unsigned int instance_no;
+	struct list_head node;
+};
+
+/*
+ * Creates hid/cid(s) string needed for modalias and uevent
+ * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get:
+ * char *modalias: "acpi:IBM0001:ACPI0001"
+*/
+static int create_modalias(struct acpi_device *acpi_dev, char *modalias,
+			   int size)
+{
+	int len;
+	int count;
+	struct acpi_hardware_id *id;
+
+	if (list_empty(&acpi_dev->pnp.ids))
+		return 0;
+
+	len = snprintf(modalias, size, "acpi:");
+	size -= len;
+
+	list_for_each_entry(id, &acpi_dev->pnp.ids, list) {
+		count = snprintf(&modalias[len], size, "%s:", id->id);
+		if (count < 0 || count >= size)
+			return -EINVAL;
+		len += count;
+		size -= count;
+	}
+
+	modalias[len] = '\0';
+	return len;
+}
+
+static ssize_t
+acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, char *buf) {
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	int len;
+
+	/* Device has no HID and no CID or string is >1024 */
+	len = create_modalias(acpi_dev, buf, 1024);
+	if (len <= 0)
+		return 0;
+	buf[len++] = '\n';
+	return len;
+}
+static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL);
+
+static void acpi_bus_hot_remove_device(void *context)
+{
+	struct acpi_device *device;
+	acpi_handle handle = context;
+	struct acpi_object_list arg_list;
+	union acpi_object arg;
+	acpi_status status = AE_OK;
+
+	if (acpi_bus_get_device(handle, &device))
+		return;
+
+	if (!device)
+		return;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+		"Hot-removing device %s...\n", dev_name(&device->dev)));
+
+	if (acpi_bus_trim(device, 1)) {
+		printk(KERN_ERR PREFIX
+				"Removing device failed\n");
+		return;
+	}
+
+	/* power off device */
+	status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
+	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
+		printk(KERN_WARNING PREFIX
+				"Power-off device failed\n");
+
+	if (device->flags.lockable) {
+		arg_list.count = 1;
+		arg_list.pointer = &arg;
+		arg.type = ACPI_TYPE_INTEGER;
+		arg.integer.value = 0;
+		acpi_evaluate_object(handle, "_LCK", &arg_list, NULL);
+	}
+
+	arg_list.count = 1;
+	arg_list.pointer = &arg;
+	arg.type = ACPI_TYPE_INTEGER;
+	arg.integer.value = 1;
+
+	/*
+	 * TBD: _EJD support.
+	 */
+	status = acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL);
+	if (ACPI_FAILURE(status))
+		printk(KERN_WARNING PREFIX
+				"Eject device failed\n");
+
+	return;
+}
+
+static ssize_t
+acpi_eject_store(struct device *d, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	int ret = count;
+	acpi_status status;
+	acpi_object_type type = 0;
+	struct acpi_device *acpi_device = to_acpi_device(d);
+
+	if ((!count) || (buf[0] != '1')) {
+		return -EINVAL;
+	}
+#ifndef FORCE_EJECT
+	if (acpi_device->driver == NULL) {
+		ret = -ENODEV;
+		goto err;
+	}
+#endif
+	status = acpi_get_type(acpi_device->handle, &type);
+	if (ACPI_FAILURE(status) || (!acpi_device->flags.ejectable)) {
+		ret = -ENODEV;
+		goto err;
+	}
+
+	acpi_os_hotplug_execute(acpi_bus_hot_remove_device, acpi_device->handle);
+err:
+	return ret;
+}
+
+static DEVICE_ATTR(eject, 0200, NULL, acpi_eject_store);
+
+static ssize_t
+acpi_device_hid_show(struct device *dev, struct device_attribute *attr, char *buf) {
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+
+	return sprintf(buf, "%s\n", acpi_device_hid(acpi_dev));
+}
+static DEVICE_ATTR(hid, 0444, acpi_device_hid_show, NULL);
+
+static ssize_t
+acpi_device_path_show(struct device *dev, struct device_attribute *attr, char *buf) {
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
+	int result;
+
+	result = acpi_get_name(acpi_dev->handle, ACPI_FULL_PATHNAME, &path);
+	if (result)
+		goto end;
+
+	result = sprintf(buf, "%s\n", (char*)path.pointer);
+	kfree(path.pointer);
+end:
+	return result;
+}
+static DEVICE_ATTR(path, 0444, acpi_device_path_show, NULL);
+
+static int acpi_device_setup_files(struct acpi_device *dev)
+{
+	acpi_status status;
+	acpi_handle temp;
+	int result = 0;
+
+	/*
+	 * Devices gotten from FADT don't have a "path" attribute
+	 */
+	if (dev->handle) {
+		result = device_create_file(&dev->dev, &dev_attr_path);
+		if (result)
+			goto end;
+	}
+
+	if (!list_empty(&dev->pnp.ids)) {
+		result = device_create_file(&dev->dev, &dev_attr_hid);
+		if (result)
+			goto end;
+
+		result = device_create_file(&dev->dev, &dev_attr_modalias);
+		if (result)
+			goto end;
+	}
+
+        /*
+         * If device has _EJ0, 'eject' file is created that is used to trigger
+         * hot-removal function from userland.
+         */
+	status = acpi_get_handle(dev->handle, "_EJ0", &temp);
+	if (ACPI_SUCCESS(status))
+		result = device_create_file(&dev->dev, &dev_attr_eject);
+end:
+	return result;
+}
+
+static void acpi_device_remove_files(struct acpi_device *dev)
+{
+	acpi_status status;
+	acpi_handle temp;
+
+	/*
+	 * If device has _EJ0, 'eject' file is created that is used to trigger
+	 * hot-removal function from userland.
+	 */
+	status = acpi_get_handle(dev->handle, "_EJ0", &temp);
+	if (ACPI_SUCCESS(status))
+		device_remove_file(&dev->dev, &dev_attr_eject);
+
+	device_remove_file(&dev->dev, &dev_attr_modalias);
+	device_remove_file(&dev->dev, &dev_attr_hid);
+	if (dev->handle)
+		device_remove_file(&dev->dev, &dev_attr_path);
+}
+/* --------------------------------------------------------------------------
+			ACPI Bus operations
+   -------------------------------------------------------------------------- */
+
+int acpi_match_device_ids(struct acpi_device *device,
+			  const struct acpi_device_id *ids)
+{
+	const struct acpi_device_id *id;
+	struct acpi_hardware_id *hwid;
+
+	/*
+	 * If the device is not present, it is unnecessary to load device
+	 * driver for it.
+	 */
+	if (!device->status.present)
+		return -ENODEV;
+
+	for (id = ids; id->id[0]; id++)
+		list_for_each_entry(hwid, &device->pnp.ids, list)
+			if (!strcmp((char *) id->id, hwid->id))
+				return 0;
+
+	return -ENOENT;
+}
+EXPORT_SYMBOL(acpi_match_device_ids);
+
+static void acpi_free_ids(struct acpi_device *device)
+{
+	struct acpi_hardware_id *id, *tmp;
+
+	list_for_each_entry_safe(id, tmp, &device->pnp.ids, list) {
+		kfree(id->id);
+		kfree(id);
+	}
+}
+
+static void acpi_device_release(struct device *dev)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+
+	acpi_free_ids(acpi_dev);
+	kfree(acpi_dev);
+}
+
+static int acpi_device_suspend(struct device *dev, pm_message_t state)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_driver *acpi_drv = acpi_dev->driver;
+
+	if (acpi_drv && acpi_drv->ops.suspend)
+		return acpi_drv->ops.suspend(acpi_dev, state);
+	return 0;
+}
+
+static int acpi_device_resume(struct device *dev)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_driver *acpi_drv = acpi_dev->driver;
+
+	if (acpi_drv && acpi_drv->ops.resume)
+		return acpi_drv->ops.resume(acpi_dev);
+	return 0;
+}
+
+static int acpi_bus_match(struct device *dev, struct device_driver *drv)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_driver *acpi_drv = to_acpi_driver(drv);
+
+	return !acpi_match_device_ids(acpi_dev, acpi_drv->ids);
+}
+
+static int acpi_device_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	int len;
+
+	if (list_empty(&acpi_dev->pnp.ids))
+		return 0;
+
+	if (add_uevent_var(env, "MODALIAS="))
+		return -ENOMEM;
+	len = create_modalias(acpi_dev, &env->buf[env->buflen - 1],
+			      sizeof(env->buf) - env->buflen);
+	if (len >= (sizeof(env->buf) - env->buflen))
+		return -ENOMEM;
+	env->buflen += len;
+	return 0;
+}
+
+static void acpi_device_notify(acpi_handle handle, u32 event, void *data)
+{
+	struct acpi_device *device = data;
+
+	device->driver->ops.notify(device, event);
+}
+
+static acpi_status acpi_device_notify_fixed(void *data)
+{
+	struct acpi_device *device = data;
+
+	/* Fixed hardware devices have no handles */
+	acpi_device_notify(NULL, ACPI_FIXED_HARDWARE_EVENT, device);
+	return AE_OK;
+}
+
+static int acpi_device_install_notify_handler(struct acpi_device *device)
+{
+	acpi_status status;
+
+	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
+		status =
+		    acpi_install_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+						     acpi_device_notify_fixed,
+						     device);
+	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
+		status =
+		    acpi_install_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
+						     acpi_device_notify_fixed,
+						     device);
+	else
+		status = acpi_install_notify_handler(device->handle,
+						     ACPI_DEVICE_NOTIFY,
+						     acpi_device_notify,
+						     device);
+
+	if (ACPI_FAILURE(status))
+		return -EINVAL;
+	return 0;
+}
+
+static void acpi_device_remove_notify_handler(struct acpi_device *device)
+{
+	if (device->device_type == ACPI_BUS_TYPE_POWER_BUTTON)
+		acpi_remove_fixed_event_handler(ACPI_EVENT_POWER_BUTTON,
+						acpi_device_notify_fixed);
+	else if (device->device_type == ACPI_BUS_TYPE_SLEEP_BUTTON)
+		acpi_remove_fixed_event_handler(ACPI_EVENT_SLEEP_BUTTON,
+						acpi_device_notify_fixed);
+	else
+		acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+					   acpi_device_notify);
+}
+
+static int acpi_bus_driver_init(struct acpi_device *, struct acpi_driver *);
+static int acpi_start_single_object(struct acpi_device *);
+static int acpi_device_probe(struct device * dev)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_driver *acpi_drv = to_acpi_driver(dev->driver);
+	int ret;
+
+	ret = acpi_bus_driver_init(acpi_dev, acpi_drv);
+	if (!ret) {
+		if (acpi_dev->bus_ops.acpi_op_start)
+			acpi_start_single_object(acpi_dev);
+
+		if (acpi_drv->ops.notify) {
+			ret = acpi_device_install_notify_handler(acpi_dev);
+			if (ret) {
+				if (acpi_drv->ops.remove)
+					acpi_drv->ops.remove(acpi_dev,
+						     acpi_dev->removal_type);
+				return ret;
+			}
+		}
+
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+			"Found driver [%s] for device [%s]\n",
+			acpi_drv->name, acpi_dev->pnp.bus_id));
+		get_device(dev);
+	}
+	return ret;
+}
+
+static int acpi_device_remove(struct device * dev)
+{
+	struct acpi_device *acpi_dev = to_acpi_device(dev);
+	struct acpi_driver *acpi_drv = acpi_dev->driver;
+
+	if (acpi_drv) {
+		if (acpi_drv->ops.notify)
+			acpi_device_remove_notify_handler(acpi_dev);
+		if (acpi_drv->ops.remove)
+			acpi_drv->ops.remove(acpi_dev, acpi_dev->removal_type);
+	}
+	acpi_dev->driver = NULL;
+	acpi_dev->driver_data = NULL;
+
+	put_device(dev);
+	return 0;
+}
+
+struct bus_type acpi_bus_type = {
+	.name		= "acpi",
+	.suspend	= acpi_device_suspend,
+	.resume		= acpi_device_resume,
+	.match		= acpi_bus_match,
+	.probe		= acpi_device_probe,
+	.remove		= acpi_device_remove,
+	.uevent		= acpi_device_uevent,
+};
+
+static int acpi_device_register(struct acpi_device *device)
+{
+	int result;
+	struct acpi_device_bus_id *acpi_device_bus_id, *new_bus_id;
+	int found = 0;
+
+	/*
+	 * Linkage
+	 * -------
+	 * Link this device to its parent and siblings.
+	 */
+	INIT_LIST_HEAD(&device->children);
+	INIT_LIST_HEAD(&device->node);
+	INIT_LIST_HEAD(&device->wakeup_list);
+
+	new_bus_id = kzalloc(sizeof(struct acpi_device_bus_id), GFP_KERNEL);
+	if (!new_bus_id) {
+		printk(KERN_ERR PREFIX "Memory allocation error\n");
+		return -ENOMEM;
+	}
+
+	mutex_lock(&acpi_device_lock);
+	/*
+	 * Find suitable bus_id and instance number in acpi_bus_id_list
+	 * If failed, create one and link it into acpi_bus_id_list
+	 */
+	list_for_each_entry(acpi_device_bus_id, &acpi_bus_id_list, node) {
+		if (!strcmp(acpi_device_bus_id->bus_id,
+			    acpi_device_hid(device))) {
+			acpi_device_bus_id->instance_no++;
+			found = 1;
+			kfree(new_bus_id);
+			break;
+		}
+	}
+	if (!found) {
+		acpi_device_bus_id = new_bus_id;
+		strcpy(acpi_device_bus_id->bus_id, acpi_device_hid(device));
+		acpi_device_bus_id->instance_no = 0;
+		list_add_tail(&acpi_device_bus_id->node, &acpi_bus_id_list);
+	}
+	dev_set_name(&device->dev, "%s:%02x", acpi_device_bus_id->bus_id, acpi_device_bus_id->instance_no);
+
+	if (device->parent)
+		list_add_tail(&device->node, &device->parent->children);
+
+	if (device->wakeup.flags.valid)
+		list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list);
+	mutex_unlock(&acpi_device_lock);
+
+	if (device->parent)
+		device->dev.parent = &device->parent->dev;
+	device->dev.bus = &acpi_bus_type;
+	device->dev.release = &acpi_device_release;
+	result = device_register(&device->dev);
+	if (result) {
+		dev_err(&device->dev, "Error registering device\n");
+		goto end;
+	}
+
+	result = acpi_device_setup_files(device);
+	if (result)
+		printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n",
+		       dev_name(&device->dev));
+
+	device->removal_type = ACPI_BUS_REMOVAL_NORMAL;
+	return 0;
+end:
+	mutex_lock(&acpi_device_lock);
+	if (device->parent)
+		list_del(&device->node);
+	list_del(&device->wakeup_list);
+	mutex_unlock(&acpi_device_lock);
+	return result;
+}
+
+static void acpi_device_unregister(struct acpi_device *device, int type)
+{
+	mutex_lock(&acpi_device_lock);
+	if (device->parent)
+		list_del(&device->node);
+
+	list_del(&device->wakeup_list);
+	mutex_unlock(&acpi_device_lock);
+
+	acpi_detach_data(device->handle, acpi_bus_data_handler);
+
+	acpi_device_remove_files(device);
+	device_unregister(&device->dev);
+}
+
+/* --------------------------------------------------------------------------
+                                 Driver Management
+   -------------------------------------------------------------------------- */
+/**
+ * acpi_bus_driver_init - add a device to a driver
+ * @device: the device to add and initialize
+ * @driver: driver for the device
+ *
+ * Used to initialize a device via its device driver.  Called whenever a
+ * driver is bound to a device.  Invokes the driver's add() ops.
+ */
+static int
+acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver)
+{
+	int result = 0;
+
+	if (!device || !driver)
+		return -EINVAL;
+
+	if (!driver->ops.add)
+		return -ENOSYS;
+
+	result = driver->ops.add(device);
+	if (result) {
+		device->driver = NULL;
+		device->driver_data = NULL;
+		return result;
+	}
+
+	device->driver = driver;
+
+	/*
+	 * TBD - Configuration Management: Assign resources to device based
+	 * upon possible configuration and currently allocated resources.
+	 */
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+			  "Driver successfully bound to device\n"));
+	return 0;
+}
+
+static int acpi_start_single_object(struct acpi_device *device)
+{
+	int result = 0;
+	struct acpi_driver *driver;
+
+
+	if (!(driver = device->driver))
+		return 0;
+
+	if (driver->ops.start) {
+		result = driver->ops.start(device);
+		if (result && driver->ops.remove)
+			driver->ops.remove(device, ACPI_BUS_REMOVAL_NORMAL);
+	}
+
+	return result;
+}
+
+/**
+ * acpi_bus_register_driver - register a driver with the ACPI bus
+ * @driver: driver being registered
+ *
+ * Registers a driver with the ACPI bus.  Searches the namespace for all
+ * devices that match the driver's criteria and binds.  Returns zero for
+ * success or a negative error status for failure.
+ */
+int acpi_bus_register_driver(struct acpi_driver *driver)
+{
+	int ret;
+
+	if (acpi_disabled)
+		return -ENODEV;
+	driver->drv.name = driver->name;
+	driver->drv.bus = &acpi_bus_type;
+	driver->drv.owner = driver->owner;
+
+	ret = driver_register(&driver->drv);
+	return ret;
+}
+
+EXPORT_SYMBOL(acpi_bus_register_driver);
+
+/**
+ * acpi_bus_unregister_driver - unregisters a driver with the APIC bus
+ * @driver: driver to unregister
+ *
+ * Unregisters a driver with the ACPI bus.  Searches the namespace for all
+ * devices that match the driver's criteria and unbinds.
+ */
+void acpi_bus_unregister_driver(struct acpi_driver *driver)
+{
+	driver_unregister(&driver->drv);
+}
+
+EXPORT_SYMBOL(acpi_bus_unregister_driver);
+
+/* --------------------------------------------------------------------------
+                                 Device Enumeration
+   -------------------------------------------------------------------------- */
+static struct acpi_device *acpi_bus_get_parent(acpi_handle handle)
+{
+	acpi_status status;
+	int ret;
+	struct acpi_device *device;
+
+	/*
+	 * Fixed hardware devices do not appear in the namespace and do not
+	 * have handles, but we fabricate acpi_devices for them, so we have
+	 * to deal with them specially.
+	 */
+	if (handle == NULL)
+		return acpi_root;
+
+	do {
+		status = acpi_get_parent(handle, &handle);
+		if (status == AE_NULL_ENTRY)
+			return NULL;
+		if (ACPI_FAILURE(status))
+			return acpi_root;
+
+		ret = acpi_bus_get_device(handle, &device);
+		if (ret == 0)
+			return device;
+	} while (1);
+}
+
+acpi_status
+acpi_bus_get_ejd(acpi_handle handle, acpi_handle *ejd)
+{
+	acpi_status status;
+	acpi_handle tmp;
+	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
+	union acpi_object *obj;
+
+	status = acpi_get_handle(handle, "_EJD", &tmp);
+	if (ACPI_FAILURE(status))
+		return status;
+
+	status = acpi_evaluate_object(handle, "_EJD", NULL, &buffer);
+	if (ACPI_SUCCESS(status)) {
+		obj = buffer.pointer;
+		status = acpi_get_handle(ACPI_ROOT_OBJECT, obj->string.pointer,
+					 ejd);
+		kfree(buffer.pointer);
+	}
+	return status;
+}
+EXPORT_SYMBOL_GPL(acpi_bus_get_ejd);
+
+void acpi_bus_data_handler(acpi_handle handle, void *context)
+{
+
+	/* TBD */
+
+	return;
+}
+
+static int acpi_bus_get_perf_flags(struct acpi_device *device)
+{
+	device->performance.state = ACPI_STATE_UNKNOWN;
+	return 0;
+}
+
+static acpi_status
+acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
+					     struct acpi_device_wakeup *wakeup)
+{
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *package = NULL;
+	union acpi_object *element = NULL;
+	acpi_status status;
+	int i = 0;
+
+	if (!wakeup)
+		return AE_BAD_PARAMETER;
+
+	/* _PRW */
+	status = acpi_evaluate_object(handle, "_PRW", NULL, &buffer);
+	if (ACPI_FAILURE(status)) {
+		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRW"));
+		return status;
+	}
+
+	package = (union acpi_object *)buffer.pointer;
+
+	if (!package || (package->package.count < 2)) {
+		status = AE_BAD_DATA;
+		goto out;
+	}
+
+	element = &(package->package.elements[0]);
+	if (!element) {
+		status = AE_BAD_DATA;
+		goto out;
+	}
+	if (element->type == ACPI_TYPE_PACKAGE) {
+		if ((element->package.count < 2) ||
+		    (element->package.elements[0].type !=
+		     ACPI_TYPE_LOCAL_REFERENCE)
+		    || (element->package.elements[1].type != ACPI_TYPE_INTEGER)) {
+			status = AE_BAD_DATA;
+			goto out;
+		}
+		wakeup->gpe_device =
+		    element->package.elements[0].reference.handle;
+		wakeup->gpe_number =
+		    (u32) element->package.elements[1].integer.value;
+	} else if (element->type == ACPI_TYPE_INTEGER) {
+		wakeup->gpe_device = NULL;
+		wakeup->gpe_number = element->integer.value;
+	} else {
+		status = AE_BAD_DATA;
+		goto out;
+	}
+
+	element = &(package->package.elements[1]);
+	if (element->type != ACPI_TYPE_INTEGER) {
+		status = AE_BAD_DATA;
+		goto out;
+	}
+	wakeup->sleep_state = element->integer.value;
+
+	if ((package->package.count - 2) > ACPI_MAX_HANDLES) {
+		status = AE_NO_MEMORY;
+		goto out;
+	}
+	wakeup->resources.count = package->package.count - 2;
+	for (i = 0; i < wakeup->resources.count; i++) {
+		element = &(package->package.elements[i + 2]);
+		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
+			status = AE_BAD_DATA;
+			goto out;
+		}
+
+		wakeup->resources.handles[i] = element->reference.handle;
+	}
+
+	acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
+
+ out:
+	kfree(buffer.pointer);
+
+	return status;
+}
+
+static void acpi_bus_set_run_wake_flags(struct acpi_device *device)
+{
+	struct acpi_device_id button_device_ids[] = {
+		{"PNP0C0C", 0},
+		{"PNP0C0D", 0},
+		{"PNP0C0E", 0},
+		{"", 0},
+	};
+	acpi_status status;
+	acpi_event_status event_status;
+
+	device->wakeup.flags.notifier_present = 0;
+
+	/* Power button, Lid switch always enable wakeup */
+	if (!acpi_match_device_ids(device, button_device_ids)) {
+		device->wakeup.flags.run_wake = 1;
+		if (!acpi_match_device_ids(device, &button_device_ids[1])) {
+			/* Do not use Lid/sleep button for S5 wakeup */
+			if (device->wakeup.sleep_state == ACPI_STATE_S5)
+				device->wakeup.sleep_state = ACPI_STATE_S4;
+		}
+		device_set_wakeup_capable(&device->dev, true);
+		return;
+	}
+
+	status = acpi_get_gpe_status(device->wakeup.gpe_device,
+					device->wakeup.gpe_number,
+						&event_status);
+	if (status == AE_OK)
+		device->wakeup.flags.run_wake =
+				!!(event_status & ACPI_EVENT_FLAG_HANDLE);
+}
+
+static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
+{
+	acpi_handle temp;
+	acpi_status status = 0;
+	int psw_error;
+
+	/* Presence of _PRW indicates wake capable */
+	status = acpi_get_handle(device->handle, "_PRW", &temp);
+	if (ACPI_FAILURE(status))
+		return;
+
+	status = acpi_bus_extract_wakeup_device_power_package(device->handle,
+							      &device->wakeup);
+	if (ACPI_FAILURE(status)) {
+		ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
+		return;
+	}
+
+	device->wakeup.flags.valid = 1;
+	device->wakeup.prepare_count = 0;
+	acpi_bus_set_run_wake_flags(device);
+	/* Call _PSW/_DSW object to disable its ability to wake the sleeping
+	 * system for the ACPI device with the _PRW object.
+	 * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW.
+	 * So it is necessary to call _DSW object first. Only when it is not
+	 * present will the _PSW object used.
+	 */
+	psw_error = acpi_device_sleep_wake(device, 0, 0, 0);
+	if (psw_error)
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+				"error in _DSW or _PSW evaluation\n"));
+}
+
+static void acpi_bus_add_power_resource(acpi_handle handle);
+
+static int acpi_bus_get_power_flags(struct acpi_device *device)
+{
+	acpi_status status = 0;
+	acpi_handle handle = NULL;
+	u32 i = 0;
+
+
+	/*
+	 * Power Management Flags
+	 */
+	status = acpi_get_handle(device->handle, "_PSC", &handle);
+	if (ACPI_SUCCESS(status))
+		device->power.flags.explicit_get = 1;
+	status = acpi_get_handle(device->handle, "_IRC", &handle);
+	if (ACPI_SUCCESS(status))
+		device->power.flags.inrush_current = 1;
+
+	/*
+	 * Enumerate supported power management states
+	 */
+	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
+		struct acpi_device_power_state *ps = &device->power.states[i];
+		char object_name[5] = { '_', 'P', 'R', '0' + i, '\0' };
+
+		/* Evaluate "_PRx" to se if power resources are referenced */
+		acpi_evaluate_reference(device->handle, object_name, NULL,
+					&ps->resources);
+		if (ps->resources.count) {
+			int j;
+
+			device->power.flags.power_resources = 1;
+			for (j = 0; j < ps->resources.count; j++)
+				acpi_bus_add_power_resource(ps->resources.handles[j]);
+		}
+
+		/* Evaluate "_PSx" to see if we can do explicit sets */
+		object_name[2] = 'S';
+		status = acpi_get_handle(device->handle, object_name, &handle);
+		if (ACPI_SUCCESS(status))
+			ps->flags.explicit_set = 1;
+
+		/*
+		 * State is valid if there are means to put the device into it.
+		 * D3hot is only valid if _PR3 present.
+		 */
+		if (ps->resources.count ||
+		    (ps->flags.explicit_set && i < ACPI_STATE_D3_HOT))
+			ps->flags.valid = 1;
+
+		ps->power = -1;	/* Unknown - driver assigned */
+		ps->latency = -1;	/* Unknown - driver assigned */
+	}
+
+	/* Set defaults for D0 and D3 states (always valid) */
+	device->power.states[ACPI_STATE_D0].flags.valid = 1;
+	device->power.states[ACPI_STATE_D0].power = 100;
+	device->power.states[ACPI_STATE_D3].flags.valid = 1;
+	device->power.states[ACPI_STATE_D3].power = 0;
+
+	/* Set D3cold's explicit_set flag if _PS3 exists. */
+	if (device->power.states[ACPI_STATE_D3_HOT].flags.explicit_set)
+		device->power.states[ACPI_STATE_D3_COLD].flags.explicit_set = 1;
+
+	acpi_bus_init_power(device);
+
+	return 0;
+}
+
+static int acpi_bus_get_flags(struct acpi_device *device)
+{
+	acpi_status status = AE_OK;
+	acpi_handle temp = NULL;
+
+
+	/* Presence of _STA indicates 'dynamic_status' */
+	status = acpi_get_handle(device->handle, "_STA", &temp);
+	if (ACPI_SUCCESS(status))
+		device->flags.dynamic_status = 1;
+
+	/* Presence of _RMV indicates 'removable' */
+	status = acpi_get_handle(device->handle, "_RMV", &temp);
+	if (ACPI_SUCCESS(status))
+		device->flags.removable = 1;
+
+	/* Presence of _EJD|_EJ0 indicates 'ejectable' */
+	status = acpi_get_handle(device->handle, "_EJD", &temp);
+	if (ACPI_SUCCESS(status))
+		device->flags.ejectable = 1;
+	else {
+		status = acpi_get_handle(device->handle, "_EJ0", &temp);
+		if (ACPI_SUCCESS(status))
+			device->flags.ejectable = 1;
+	}
+
+	/* Presence of _LCK indicates 'lockable' */
+	status = acpi_get_handle(device->handle, "_LCK", &temp);
+	if (ACPI_SUCCESS(status))
+		device->flags.lockable = 1;
+
+	/* Power resources cannot be power manageable. */
+	if (device->device_type == ACPI_BUS_TYPE_POWER)
+		return 0;
+
+	/* Presence of _PS0|_PR0 indicates 'power manageable' */
+	status = acpi_get_handle(device->handle, "_PS0", &temp);
+	if (ACPI_FAILURE(status))
+		status = acpi_get_handle(device->handle, "_PR0", &temp);
+	if (ACPI_SUCCESS(status))
+		device->flags.power_manageable = 1;
+
+	/* TBD: Performance management */
+
+	return 0;
+}
+
+static void acpi_device_get_busid(struct acpi_device *device)
+{
+	char bus_id[5] = { '?', 0 };
+	struct acpi_buffer buffer = { sizeof(bus_id), bus_id };
+	int i = 0;
+
+	/*
+	 * Bus ID
+	 * ------
+	 * The device's Bus ID is simply the object name.
+	 * TBD: Shouldn't this value be unique (within the ACPI namespace)?
+	 */
+	if (ACPI_IS_ROOT_DEVICE(device)) {
+		strcpy(device->pnp.bus_id, "ACPI");
+		return;
+	}
+
+	switch (device->device_type) {
+	case ACPI_BUS_TYPE_POWER_BUTTON:
+		strcpy(device->pnp.bus_id, "PWRF");
+		break;
+	case ACPI_BUS_TYPE_SLEEP_BUTTON:
+		strcpy(device->pnp.bus_id, "SLPF");
+		break;
+	default:
+		acpi_get_name(device->handle, ACPI_SINGLE_NAME, &buffer);
+		/* Clean up trailing underscores (if any) */
+		for (i = 3; i > 1; i--) {
+			if (bus_id[i] == '_')
+				bus_id[i] = '\0';
+			else
+				break;
+		}
+		strcpy(device->pnp.bus_id, bus_id);
+		break;
+	}
+}
+
+/*
+ * acpi_bay_match - see if a device is an ejectable driver bay
+ *
+ * If an acpi object is ejectable and has one of the ACPI ATA methods defined,
+ * then we can safely call it an ejectable drive bay
+ */
+static int acpi_bay_match(struct acpi_device *device){
+	acpi_status status;
+	acpi_handle handle;
+	acpi_handle tmp;
+	acpi_handle phandle;
+
+	handle = device->handle;
+
+	status = acpi_get_handle(handle, "_EJ0", &tmp);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
+		(ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
+		(ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
+		(ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
+		return 0;
+
+	if (acpi_get_parent(handle, &phandle))
+		return -ENODEV;
+
+        if ((ACPI_SUCCESS(acpi_get_handle(phandle, "_GTF", &tmp))) ||
+                (ACPI_SUCCESS(acpi_get_handle(phandle, "_GTM", &tmp))) ||
+                (ACPI_SUCCESS(acpi_get_handle(phandle, "_STM", &tmp))) ||
+                (ACPI_SUCCESS(acpi_get_handle(phandle, "_SDD", &tmp))))
+                return 0;
+
+	return -ENODEV;
+}
+
+/*
+ * acpi_dock_match - see if a device has a _DCK method
+ */
+static int acpi_dock_match(struct acpi_device *device)
+{
+	acpi_handle tmp;
+	return acpi_get_handle(device->handle, "_DCK", &tmp);
+}
+
+const char *acpi_device_hid(struct acpi_device *device)
+{
+	struct acpi_hardware_id *hid;
+
+	if (list_empty(&device->pnp.ids))
+		return dummy_hid;
+
+	hid = list_first_entry(&device->pnp.ids, struct acpi_hardware_id, list);
+	return hid->id;
+}
+EXPORT_SYMBOL(acpi_device_hid);
+
+static void acpi_add_id(struct acpi_device *device, const char *dev_id)
+{
+	struct acpi_hardware_id *id;
+
+	id = kmalloc(sizeof(*id), GFP_KERNEL);
+	if (!id)
+		return;
+
+	id->id = kstrdup(dev_id, GFP_KERNEL);
+	if (!id->id) {
+		kfree(id);
+		return;
+	}
+
+	list_add_tail(&id->list, &device->pnp.ids);
+}
+
+/*
+ * Old IBM workstations have a DSDT bug wherein the SMBus object
+ * lacks the SMBUS01 HID and the methods do not have the necessary "_"
+ * prefix.  Work around this.
+ */
+static int acpi_ibm_smbus_match(struct acpi_device *device)
+{
+	acpi_handle h_dummy;
+	struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL};
+	int result;
+
+	if (!dmi_name_in_vendors("IBM"))
+		return -ENODEV;
+
+	/* Look for SMBS object */
+	result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path);
+	if (result)
+		return result;
+
+	if (strcmp("SMBS", path.pointer)) {
+		result = -ENODEV;
+		goto out;
+	}
+
+	/* Does it have the necessary (but misnamed) methods? */
+	result = -ENODEV;
+	if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) &&
+	    ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) &&
+	    ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy)))
+		result = 0;
+out:
+	kfree(path.pointer);
+	return result;
+}
+
+static void acpi_device_set_id(struct acpi_device *device)
+{
+	acpi_status status;
+	struct acpi_device_info *info;
+	struct acpica_device_id_list *cid_list;
+	int i;
+
+	switch (device->device_type) {
+	case ACPI_BUS_TYPE_DEVICE:
+		if (ACPI_IS_ROOT_DEVICE(device)) {
+			acpi_add_id(device, ACPI_SYSTEM_HID);
+			break;
+		}
+
+		status = acpi_get_object_info(device->handle, &info);
+		if (ACPI_FAILURE(status)) {
+			printk(KERN_ERR PREFIX "%s: Error reading device info\n", __func__);
+			return;
+		}
+
+		if (info->valid & ACPI_VALID_HID)
+			acpi_add_id(device, info->hardware_id.string);
+		if (info->valid & ACPI_VALID_CID) {
+			cid_list = &info->compatible_id_list;
+			for (i = 0; i < cid_list->count; i++)
+				acpi_add_id(device, cid_list->ids[i].string);
+		}
+		if (info->valid & ACPI_VALID_ADR) {
+			device->pnp.bus_address = info->address;
+			device->flags.bus_address = 1;
+		}
+
+		kfree(info);
+
+		/*
+		 * Some devices don't reliably have _HIDs & _CIDs, so add
+		 * synthetic HIDs to make sure drivers can find them.
+		 */
+		if (acpi_is_video_device(device))
+			acpi_add_id(device, ACPI_VIDEO_HID);
+		else if (ACPI_SUCCESS(acpi_bay_match(device)))
+			acpi_add_id(device, ACPI_BAY_HID);
+		else if (ACPI_SUCCESS(acpi_dock_match(device)))
+			acpi_add_id(device, ACPI_DOCK_HID);
+		else if (!acpi_ibm_smbus_match(device))
+			acpi_add_id(device, ACPI_SMBUS_IBM_HID);
+		else if (list_empty(&device->pnp.ids) &&
+			 ACPI_IS_ROOT_DEVICE(device->parent)) {
+			acpi_add_id(device, ACPI_BUS_HID); /* \_SB, LNXSYBUS */
+			strcpy(device->pnp.device_name, ACPI_BUS_DEVICE_NAME);
+			strcpy(device->pnp.device_class, ACPI_BUS_CLASS);
+		}
+
+		break;
+	case ACPI_BUS_TYPE_POWER:
+		acpi_add_id(device, ACPI_POWER_HID);
+		break;
+	case ACPI_BUS_TYPE_PROCESSOR:
+		acpi_add_id(device, ACPI_PROCESSOR_OBJECT_HID);
+		break;
+	case ACPI_BUS_TYPE_THERMAL:
+		acpi_add_id(device, ACPI_THERMAL_HID);
+		break;
+	case ACPI_BUS_TYPE_POWER_BUTTON:
+		acpi_add_id(device, ACPI_BUTTON_HID_POWERF);
+		break;
+	case ACPI_BUS_TYPE_SLEEP_BUTTON:
+		acpi_add_id(device, ACPI_BUTTON_HID_SLEEPF);
+		break;
+	}
+}
+
+static int acpi_device_set_context(struct acpi_device *device)
+{
+	acpi_status status;
+
+	/*
+	 * Context
+	 * -------
+	 * Attach this 'struct acpi_device' to the ACPI object.  This makes
+	 * resolutions from handle->device very efficient.  Fixed hardware
+	 * devices have no handles, so we skip them.
+	 */
+	if (!device->handle)
+		return 0;
+
+	status = acpi_attach_data(device->handle,
+				  acpi_bus_data_handler, device);
+	if (ACPI_SUCCESS(status))
+		return 0;
+
+	printk(KERN_ERR PREFIX "Error attaching device data\n");
+	return -ENODEV;
+}
+
+static int acpi_bus_remove(struct acpi_device *dev, int rmdevice)
+{
+	if (!dev)
+		return -EINVAL;
+
+	dev->removal_type = ACPI_BUS_REMOVAL_EJECT;
+	device_release_driver(&dev->dev);
+
+	if (!rmdevice)
+		return 0;
+
+	/*
+	 * unbind _ADR-Based Devices when hot removal
+	 */
+	if (dev->flags.bus_address) {
+		if ((dev->parent) && (dev->parent->ops.unbind))
+			dev->parent->ops.unbind(dev);
+	}
+	acpi_device_unregister(dev, ACPI_BUS_REMOVAL_EJECT);
+
+	return 0;
+}
+
+static int acpi_add_single_object(struct acpi_device **child,
+				  acpi_handle handle, int type,
+				  unsigned long long sta,
+				  struct acpi_bus_ops *ops)
+{
+	int result;
+	struct acpi_device *device;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+
+	device = kzalloc(sizeof(struct acpi_device), GFP_KERNEL);
+	if (!device) {
+		printk(KERN_ERR PREFIX "Memory allocation error\n");
+		return -ENOMEM;
+	}
+
+	INIT_LIST_HEAD(&device->pnp.ids);
+	device->device_type = type;
+	device->handle = handle;
+	device->parent = acpi_bus_get_parent(handle);
+	device->bus_ops = *ops; /* workround for not call .start */
+	STRUCT_TO_INT(device->status) = sta;
+
+	acpi_device_get_busid(device);
+
+	/*
+	 * Flags
+	 * -----
+	 * Note that we only look for object handles -- cannot evaluate objects
+	 * until we know the device is present and properly initialized.
+	 */
+	result = acpi_bus_get_flags(device);
+	if (result)
+		goto end;
+
+	/*
+	 * Initialize Device
+	 * -----------------
+	 * TBD: Synch with Core's enumeration/initialization process.
+	 */
+	acpi_device_set_id(device);
+
+	/*
+	 * Power Management
+	 * ----------------
+	 */
+	if (device->flags.power_manageable) {
+		result = acpi_bus_get_power_flags(device);
+		if (result)
+			goto end;
+	}
+
+	/*
+	 * Wakeup device management
+	 *-----------------------
+	 */
+	acpi_bus_get_wakeup_device_flags(device);
+
+	/*
+	 * Performance Management
+	 * ----------------------
+	 */
+	if (device->flags.performance_manageable) {
+		result = acpi_bus_get_perf_flags(device);
+		if (result)
+			goto end;
+	}
+
+	if ((result = acpi_device_set_context(device)))
+		goto end;
+
+	result = acpi_device_register(device);
+
+	/*
+	 * Bind _ADR-Based Devices when hot add
+	 */
+	if (device->flags.bus_address) {
+		if (device->parent && device->parent->ops.bind)
+			device->parent->ops.bind(device);
+	}
+
+end:
+	if (!result) {
+		acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+			"Adding %s [%s] parent %s\n", dev_name(&device->dev),
+			 (char *) buffer.pointer,
+			 device->parent ? dev_name(&device->parent->dev) :
+					  "(null)"));
+		kfree(buffer.pointer);
+		*child = device;
+	} else
+		acpi_device_release(&device->dev);
+
+	return result;
+}
+
+#define ACPI_STA_DEFAULT (ACPI_STA_DEVICE_PRESENT | ACPI_STA_DEVICE_ENABLED | \
+			  ACPI_STA_DEVICE_UI      | ACPI_STA_DEVICE_FUNCTIONING)
+
+static void acpi_bus_add_power_resource(acpi_handle handle)
+{
+	struct acpi_bus_ops ops = {
+		.acpi_op_add = 1,
+		.acpi_op_start = 1,
+	};
+	struct acpi_device *device = NULL;
+
+	acpi_bus_get_device(handle, &device);
+	if (!device)
+		acpi_add_single_object(&device, handle, ACPI_BUS_TYPE_POWER,
+					ACPI_STA_DEFAULT, &ops);
+}
+
+static int acpi_bus_type_and_status(acpi_handle handle, int *type,
+				    unsigned long long *sta)
+{
+	acpi_status status;
+	acpi_object_type acpi_type;
+
+	status = acpi_get_type(handle, &acpi_type);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	switch (acpi_type) {
+	case ACPI_TYPE_ANY:		/* for ACPI_ROOT_OBJECT */
+	case ACPI_TYPE_DEVICE:
+		*type = ACPI_BUS_TYPE_DEVICE;
+		status = acpi_bus_get_status_handle(handle, sta);
+		if (ACPI_FAILURE(status))
+			return -ENODEV;
+		break;
+	case ACPI_TYPE_PROCESSOR:
+		*type = ACPI_BUS_TYPE_PROCESSOR;
+		status = acpi_bus_get_status_handle(handle, sta);
+		if (ACPI_FAILURE(status))
+			return -ENODEV;
+		break;
+	case ACPI_TYPE_THERMAL:
+		*type = ACPI_BUS_TYPE_THERMAL;
+		*sta = ACPI_STA_DEFAULT;
+		break;
+	case ACPI_TYPE_POWER:
+		*type = ACPI_BUS_TYPE_POWER;
+		*sta = ACPI_STA_DEFAULT;
+		break;
+	default:
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static acpi_status acpi_bus_check_add(acpi_handle handle, u32 lvl,
+				      void *context, void **return_value)
+{
+	struct acpi_bus_ops *ops = context;
+	int type;
+	unsigned long long sta;
+	struct acpi_device *device;
+	acpi_status status;
+	int result;
+
+	result = acpi_bus_type_and_status(handle, &type, &sta);
+	if (result)
+		return AE_OK;
+
+	if (!(sta & ACPI_STA_DEVICE_PRESENT) &&
+	    !(sta & ACPI_STA_DEVICE_FUNCTIONING)) {
+		struct acpi_device_wakeup wakeup;
+		acpi_handle temp;
+
+		status = acpi_get_handle(handle, "_PRW", &temp);
+		if (ACPI_SUCCESS(status))
+			acpi_bus_extract_wakeup_device_power_package(handle,
+								     &wakeup);
+		return AE_CTRL_DEPTH;
+	}
+
+	/*
+	 * We may already have an acpi_device from a previous enumeration.  If
+	 * so, we needn't add it again, but we may still have to start it.
+	 */
+	device = NULL;
+	acpi_bus_get_device(handle, &device);
+	if (ops->acpi_op_add && !device)
+		acpi_add_single_object(&device, handle, type, sta, ops);
+
+	if (!device)
+		return AE_CTRL_DEPTH;
+
+	if (ops->acpi_op_start && !(ops->acpi_op_add)) {
+		status = acpi_start_single_object(device);
+		if (ACPI_FAILURE(status))
+			return AE_CTRL_DEPTH;
+	}
+
+	if (!*return_value)
+		*return_value = device;
+	return AE_OK;
+}
+
+static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops,
+			 struct acpi_device **child)
+{
+	acpi_status status;
+	void *device = NULL;
+
+	status = acpi_bus_check_add(handle, 0, ops, &device);
+	if (ACPI_SUCCESS(status))
+		acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
+				    acpi_bus_check_add, NULL, ops, &device);
+
+	if (child)
+		*child = device;
+
+	if (device)
+		return 0;
+	else
+		return -ENODEV;
+}
+
+/*
+ * acpi_bus_add and acpi_bus_start
+ *
+ * scan a given ACPI tree and (probably recently hot-plugged)
+ * create and add or starts found devices.
+ *
+ * If no devices were found -ENODEV is returned which does not
+ * mean that this is a real error, there just have been no suitable
+ * ACPI objects in the table trunk from which the kernel could create
+ * a device and add/start an appropriate driver.
+ */
+
+int
+acpi_bus_add(struct acpi_device **child,
+	     struct acpi_device *parent, acpi_handle handle, int type)
+{
+	struct acpi_bus_ops ops;
+
+	memset(&ops, 0, sizeof(ops));
+	ops.acpi_op_add = 1;
+
+	return acpi_bus_scan(handle, &ops, child);
+}
+EXPORT_SYMBOL(acpi_bus_add);
+
+int acpi_bus_start(struct acpi_device *device)
+{
+	struct acpi_bus_ops ops;
+	int result;
+
+	if (!device)
+		return -EINVAL;
+
+	memset(&ops, 0, sizeof(ops));
+	ops.acpi_op_start = 1;
+
+	result = acpi_bus_scan(device->handle, &ops, NULL);
+
+	acpi_update_all_gpes();
+
+	return result;
+}
+EXPORT_SYMBOL(acpi_bus_start);
+
+int acpi_bus_trim(struct acpi_device *start, int rmdevice)
+{
+	acpi_status status;
+	struct acpi_device *parent, *child;
+	acpi_handle phandle, chandle;
+	acpi_object_type type;
+	u32 level = 1;
+	int err = 0;
+
+	parent = start;
+	phandle = start->handle;
+	child = chandle = NULL;
+
+	while ((level > 0) && parent && (!err)) {
+		status = acpi_get_next_object(ACPI_TYPE_ANY, phandle,
+					      chandle, &chandle);
+
+		/*
+		 * If this scope is exhausted then move our way back up.
+		 */
+		if (ACPI_FAILURE(status)) {
+			level--;
+			chandle = phandle;
+			acpi_get_parent(phandle, &phandle);
+			child = parent;
+			parent = parent->parent;
+
+			if (level == 0)
+				err = acpi_bus_remove(child, rmdevice);
+			else
+				err = acpi_bus_remove(child, 1);
+
+			continue;
+		}
+
+		status = acpi_get_type(chandle, &type);
+		if (ACPI_FAILURE(status)) {
+			continue;
+		}
+		/*
+		 * If there is a device corresponding to chandle then
+		 * parse it (depth-first).
+		 */
+		if (acpi_bus_get_device(chandle, &child) == 0) {
+			level++;
+			phandle = chandle;
+			chandle = NULL;
+			parent = child;
+		}
+		continue;
+	}
+	return err;
+}
+EXPORT_SYMBOL_GPL(acpi_bus_trim);
+
+static int acpi_bus_scan_fixed(void)
+{
+	int result = 0;
+	struct acpi_device *device = NULL;
+	struct acpi_bus_ops ops;
+
+	memset(&ops, 0, sizeof(ops));
+	ops.acpi_op_add = 1;
+	ops.acpi_op_start = 1;
+
+	/*
+	 * Enumerate all fixed-feature devices.
+	 */
+	if ((acpi_gbl_FADT.flags & ACPI_FADT_POWER_BUTTON) == 0) {
+		result = acpi_add_single_object(&device, NULL,
+						ACPI_BUS_TYPE_POWER_BUTTON,
+						ACPI_STA_DEFAULT,
+						&ops);
+	}
+
+	if ((acpi_gbl_FADT.flags & ACPI_FADT_SLEEP_BUTTON) == 0) {
+		result = acpi_add_single_object(&device, NULL,
+						ACPI_BUS_TYPE_SLEEP_BUTTON,
+						ACPI_STA_DEFAULT,
+						&ops);
+	}
+
+	return result;
+}
+
+int __init acpi_scan_init(void)
+{
+	int result;
+	struct acpi_bus_ops ops;
+
+	memset(&ops, 0, sizeof(ops));
+	ops.acpi_op_add = 1;
+	ops.acpi_op_start = 1;
+
+	result = bus_register(&acpi_bus_type);
+	if (result) {
+		/* We don't want to quit even if we failed to add suspend/resume */
+		printk(KERN_ERR PREFIX "Could not register bus type\n");
+	}
+
+	acpi_power_init();
+
+	/*
+	 * Enumerate devices in the ACPI namespace.
+	 */
+	result = acpi_bus_scan(ACPI_ROOT_OBJECT, &ops, &acpi_root);
+
+	if (!result)
+		result = acpi_bus_scan_fixed();
+
+	if (result)
+		acpi_device_unregister(acpi_root, ACPI_BUS_REMOVAL_NORMAL);
+	else
+		acpi_update_all_gpes();
+
+	return result;
+}