diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
new file mode 100644
index 0000000..373a3a9
--- /dev/null
+++ b/drivers/acpi/power.c
@@ -0,0 +1,692 @@
+/*
+ *  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/proc_fs.h>
+#include <linux/seq_file.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+
+#define _COMPONENT		ACPI_POWER_COMPONENT
+ACPI_MODULE_NAME		("acpi_power")
+
+#define ACPI_POWER_COMPONENT		0x00800000
+#define ACPI_POWER_CLASS		"power_resource"
+#define ACPI_POWER_DRIVER_NAME		"ACPI Power Resource Driver"
+#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
+
+static int acpi_power_add (struct acpi_device *device);
+static int acpi_power_remove (struct acpi_device *device, int type);
+static int acpi_power_open_fs(struct inode *inode, struct file *file);
+
+static struct acpi_driver acpi_power_driver = {
+	.name =		ACPI_POWER_DRIVER_NAME,
+	.class =	ACPI_POWER_CLASS,
+	.ids =		ACPI_POWER_HID,
+	.ops =		{
+				.add =		acpi_power_add,
+				.remove =	acpi_power_remove,
+			},
+};
+
+struct acpi_power_resource
+{
+	acpi_handle		handle;
+	acpi_bus_id		name;
+	u32			system_level;
+	u32			order;
+	int			state;
+	int			references;
+};
+
+static struct list_head		acpi_power_resource_list;
+
+static struct file_operations acpi_power_fops = {
+	.open		= acpi_power_open_fs,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+/* --------------------------------------------------------------------------
+                             Power Resource Management
+   -------------------------------------------------------------------------- */
+
+static int
+acpi_power_get_context (
+	acpi_handle		handle,
+	struct acpi_power_resource **resource)
+{
+	int			result = 0;
+	struct acpi_device	*device = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_power_get_context");
+
+	if (!resource)
+		return_VALUE(-ENODEV);
+
+	result = acpi_bus_get_device(handle, &device);
+	if (result) {
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Error getting context [%p]\n",
+			handle));
+		return_VALUE(result);
+	}
+
+	*resource = (struct acpi_power_resource *) acpi_driver_data(device);
+	if (!resource)
+		return_VALUE(-ENODEV);
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_power_get_state (
+	struct acpi_power_resource *resource)
+{
+	acpi_status		status = AE_OK;
+	unsigned long		sta = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_power_get_state");
+
+	if (!resource)
+		return_VALUE(-EINVAL);
+
+	status = acpi_evaluate_integer(resource->handle, "_STA", NULL, &sta);
+	if (ACPI_FAILURE(status))
+		return_VALUE(-ENODEV);
+
+	if (sta & 0x01)
+		resource->state = ACPI_POWER_RESOURCE_STATE_ON;
+	else
+		resource->state = ACPI_POWER_RESOURCE_STATE_OFF;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
+		resource->name, resource->state?"on":"off"));
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_power_get_list_state (
+	struct acpi_handle_list	*list,
+	int			*state)
+{
+	int			result = 0;
+	struct acpi_power_resource *resource = NULL;
+	u32			i = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_power_get_list_state");
+
+	if (!list || !state)
+		return_VALUE(-EINVAL);
+
+	/* The state of the list is 'on' IFF all resources are 'on'. */
+
+	for (i=0; i<list->count; i++) {
+		result = acpi_power_get_context(list->handles[i], &resource);
+		if (result)
+			return_VALUE(result);
+		result = acpi_power_get_state(resource);
+		if (result)
+			return_VALUE(result);
+
+		*state = resource->state;
+
+		if (*state != ACPI_POWER_RESOURCE_STATE_ON)
+			break;
+	}
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
+		*state?"on":"off"));
+
+	return_VALUE(result);
+}
+
+
+static int
+acpi_power_on (
+	acpi_handle		handle)
+{
+	int			result = 0;
+	acpi_status		status = AE_OK;
+	struct acpi_device	*device = NULL;
+	struct acpi_power_resource *resource = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_power_on");
+
+	result = acpi_power_get_context(handle, &resource);
+	if (result)
+		return_VALUE(result);
+
+	resource->references++;
+
+	if ((resource->references > 1) 
+		|| (resource->state == ACPI_POWER_RESOURCE_STATE_ON)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already on\n",
+			resource->name));
+		return_VALUE(0);
+	}
+
+	status = acpi_evaluate_object(resource->handle, "_ON", NULL, NULL);
+	if (ACPI_FAILURE(status))
+		return_VALUE(-ENODEV);
+
+	result = acpi_power_get_state(resource);
+	if (result)
+		return_VALUE(result);
+	if (resource->state != ACPI_POWER_RESOURCE_STATE_ON)
+		return_VALUE(-ENOEXEC);
+
+	/* Update the power resource's _device_ power state */
+	result = acpi_bus_get_device(resource->handle, &device);
+	if (result)
+		return_VALUE(result);
+	device->power.state = ACPI_STATE_D0;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned on\n",
+		resource->name));
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_power_off_device (
+	acpi_handle		handle)
+{
+	int			result = 0;
+	acpi_status		status = AE_OK;
+	struct acpi_device	*device = NULL;
+	struct acpi_power_resource *resource = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_power_off_device");
+
+	result = acpi_power_get_context(handle, &resource);
+	if (result)
+		return_VALUE(result);
+
+	if (resource->references)
+		resource->references--;
+
+	if (resource->references) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
+			"Resource [%s] is still in use, dereferencing\n",
+			device->pnp.bus_id));
+		return_VALUE(0);
+	}
+
+	if (resource->state == ACPI_POWER_RESOURCE_STATE_OFF) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already off\n",
+			device->pnp.bus_id));
+		return_VALUE(0);
+	}
+
+	status = acpi_evaluate_object(resource->handle, "_OFF", NULL, NULL);
+	if (ACPI_FAILURE(status))
+		return_VALUE(-ENODEV);
+
+	result = acpi_power_get_state(resource);
+	if (result)
+		return_VALUE(result);
+	if (resource->state != ACPI_POWER_RESOURCE_STATE_OFF)
+		return_VALUE(-ENOEXEC);
+
+	/* Update the power resource's _device_ power state */
+	result = acpi_bus_get_device(resource->handle, &device);
+	if (result)
+		return_VALUE(result);
+	device->power.state = ACPI_STATE_D3;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n",
+		resource->name));
+
+	return_VALUE(0);
+}
+
+/*
+ * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
+ * 1. Power on the power resources required for the wakeup device 
+ * 2. Enable _PSW (power state wake) for the device if present
+ */
+int acpi_enable_wakeup_device_power (struct acpi_device *dev)
+{
+	union acpi_object 		arg = {ACPI_TYPE_INTEGER};
+	struct acpi_object_list	arg_list = {1, &arg};
+	acpi_status			status = AE_OK;
+	int					i;
+	int 					ret = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_enable_wakeup_device_power");
+	if (!dev || !dev->wakeup.flags.valid)
+		return_VALUE(-1);
+
+	arg.integer.value = 1;
+	/* Open power resource */
+	for (i = 0; i < dev->wakeup.resources.count; i++) {
+		ret = acpi_power_on(dev->wakeup.resources.handles[i]);
+		if (ret) {
+			ACPI_DEBUG_PRINT((ACPI_DB_ERROR, 
+				"Error transition power state\n"));
+			dev->wakeup.flags.valid = 0;
+			return_VALUE(-1);
+		}
+	}
+
+	/* Execute PSW */
+	status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
+	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluate _PSW\n"));
+		dev->wakeup.flags.valid = 0;
+		ret = -1;
+	}
+
+	return_VALUE(ret);
+}
+
+/*
+ * Shutdown a wakeup device, counterpart of above method
+ * 1. Disable _PSW (power state wake)
+ * 2. Shutdown down the power resources
+ */
+int acpi_disable_wakeup_device_power (struct acpi_device *dev)
+{
+	union acpi_object 		arg = {ACPI_TYPE_INTEGER};
+	struct acpi_object_list	arg_list = {1, &arg};
+	acpi_status			status = AE_OK;
+	int					i;
+	int 					ret = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_disable_wakeup_device_power");
+
+	if (!dev || !dev->wakeup.flags.valid)
+		return_VALUE(-1);
+
+	arg.integer.value = 0;	
+	/* Execute PSW */
+	status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
+	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluate _PSW\n"));
+		dev->wakeup.flags.valid = 0;
+		return_VALUE(-1);
+	}
+
+	/* Close power resource */
+	for (i = 0; i < dev->wakeup.resources.count; i++) {
+		ret = acpi_power_off_device(dev->wakeup.resources.handles[i]);
+		if (ret) {
+			ACPI_DEBUG_PRINT((ACPI_DB_ERROR, 
+				"Error transition power state\n"));
+			dev->wakeup.flags.valid = 0;
+			return_VALUE(-1);
+		}
+	}
+
+	return_VALUE(ret);
+}
+
+/* --------------------------------------------------------------------------
+                             Device Power Management
+   -------------------------------------------------------------------------- */
+
+int
+acpi_power_get_inferred_state (
+	struct acpi_device	*device)
+{
+	int			result = 0;
+	struct acpi_handle_list	*list = NULL;
+	int			list_state = 0;
+	int			i = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_power_get_inferred_state");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	device->power.state = ACPI_STATE_UNKNOWN;
+
+	/*
+	 * 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; i++) {
+		list = &device->power.states[i].resources;
+		if (list->count < 1)
+			continue;
+
+		result = acpi_power_get_list_state(list, &list_state);
+		if (result)
+			return_VALUE(result);
+
+		if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
+			device->power.state = i;
+			return_VALUE(0);
+		}
+	}
+
+	device->power.state = ACPI_STATE_D3;
+
+	return_VALUE(0);
+}
+
+
+int
+acpi_power_transition (
+	struct acpi_device	*device,
+	int			state)
+{
+	int			result = 0;
+	struct acpi_handle_list	*cl = NULL;	/* Current Resources */
+	struct acpi_handle_list	*tl = NULL;	/* Target Resources */
+	int			i = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_power_transition");
+
+	if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
+		return_VALUE(-EINVAL);
+
+	if ((device->power.state < ACPI_STATE_D0) || (device->power.state > ACPI_STATE_D3))
+		return_VALUE(-ENODEV);
+
+	cl = &device->power.states[device->power.state].resources;
+	tl = &device->power.states[state].resources;
+
+	device->power.state = ACPI_STATE_UNKNOWN;
+
+	if (!cl->count && !tl->count) {
+		result = -ENODEV;
+		goto end;
+	}
+
+	/* 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).
+	 */
+	for (i=0; i<tl->count; i++) {
+		result = acpi_power_on(tl->handles[i]);
+		if (result)
+			goto end;
+	}
+
+	/*
+	 * Then we dereference all power resources used in the current list.
+	 */
+	for (i=0; i<cl->count; i++) {
+		result = acpi_power_off_device(cl->handles[i]);
+		if (result)
+			goto end;
+	}
+
+	/* We shouldn't change the state till all above operations succeed */
+	device->power.state = state;
+end:
+	if (result)
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, 
+			"Error transitioning device [%s] to D%d\n",
+			device->pnp.bus_id, state));
+
+	return_VALUE(result);
+}
+
+
+/* --------------------------------------------------------------------------
+                              FS Interface (/proc)
+   -------------------------------------------------------------------------- */
+
+static struct proc_dir_entry	*acpi_power_dir;
+
+static int acpi_power_seq_show(struct seq_file *seq, void *offset)
+{
+	struct acpi_power_resource *resource = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_power_seq_show");
+
+	resource = (struct acpi_power_resource *)seq->private;
+
+	if (!resource)
+		goto end;
+
+	seq_puts(seq, "state:                   ");
+	switch (resource->state) {
+	case ACPI_POWER_RESOURCE_STATE_ON:
+		seq_puts(seq, "on\n");
+		break;
+	case ACPI_POWER_RESOURCE_STATE_OFF:
+		seq_puts(seq, "off\n");
+		break;
+	default:
+		seq_puts(seq, "unknown\n");
+		break;
+	}
+
+	seq_printf(seq, "system level:            S%d\n"
+			"order:                   %d\n"
+			"reference count:         %d\n",
+			resource->system_level,
+			resource->order,
+			resource->references);
+
+end:
+	return_VALUE(0);
+}
+
+static int acpi_power_open_fs(struct inode *inode, struct file *file)
+{
+	return single_open(file, acpi_power_seq_show, PDE(inode)->data);
+}
+
+static int
+acpi_power_add_fs (
+	struct acpi_device	*device)
+{
+	struct proc_dir_entry	*entry = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_power_add_fs");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	if (!acpi_device_dir(device)) {
+		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
+			acpi_power_dir);
+		if (!acpi_device_dir(device))
+			return_VALUE(-ENODEV);
+	}
+
+	/* 'status' [R] */
+	entry = create_proc_entry(ACPI_POWER_FILE_STATUS,
+		S_IRUGO, acpi_device_dir(device));
+	if (!entry)
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Unable to create '%s' fs entry\n",
+			ACPI_POWER_FILE_STATUS));
+	else {
+		entry->proc_fops = &acpi_power_fops;
+		entry->data = acpi_driver_data(device);
+	}
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_power_remove_fs (
+	struct acpi_device	*device)
+{
+	ACPI_FUNCTION_TRACE("acpi_power_remove_fs");
+
+	if (acpi_device_dir(device)) {
+		remove_proc_entry(ACPI_POWER_FILE_STATUS,
+				  acpi_device_dir(device));
+		remove_proc_entry(acpi_device_bid(device), acpi_power_dir);
+		acpi_device_dir(device) = NULL;
+	}
+
+	return_VALUE(0);
+}
+
+
+/* --------------------------------------------------------------------------
+                                Driver Interface
+   -------------------------------------------------------------------------- */
+
+static int
+acpi_power_add (
+	struct acpi_device	*device)
+{
+	int			result = 0;
+	acpi_status		status = AE_OK;
+	struct acpi_power_resource *resource = NULL;
+	union acpi_object	acpi_object;
+	struct acpi_buffer	buffer = {sizeof(acpi_object), &acpi_object};
+
+	ACPI_FUNCTION_TRACE("acpi_power_add");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	resource = kmalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
+	if (!resource)
+		return_VALUE(-ENOMEM);
+	memset(resource, 0, sizeof(struct acpi_power_resource));
+
+	resource->handle = device->handle;
+	strcpy(resource->name, device->pnp.bus_id);
+	strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
+	strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
+	acpi_driver_data(device) = resource;
+
+	/* Evalute the object to get the system level and resource order. */
+	status = acpi_evaluate_object(resource->handle, NULL, NULL, &buffer);
+	if (ACPI_FAILURE(status)) {
+		result = -ENODEV;
+		goto end;
+	}
+	resource->system_level = acpi_object.power_resource.system_level;
+	resource->order = acpi_object.power_resource.resource_order;
+
+	result = acpi_power_get_state(resource);
+	if (result)
+		goto end;
+
+	switch (resource->state) {
+	case ACPI_POWER_RESOURCE_STATE_ON:
+		device->power.state = ACPI_STATE_D0;
+		break;
+	case ACPI_POWER_RESOURCE_STATE_OFF:
+		device->power.state = ACPI_STATE_D3;
+		break;
+	default:
+		device->power.state = ACPI_STATE_UNKNOWN;
+		break;
+	}
+
+	result = acpi_power_add_fs(device);
+	if (result)
+		goto end;
+	
+	printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
+		acpi_device_bid(device), resource->state?"on":"off");
+
+end:
+	if (result)
+		kfree(resource);
+	
+	return_VALUE(result);
+}
+
+
+static int
+acpi_power_remove (
+	struct acpi_device	*device,
+	int			type)
+{
+	struct acpi_power_resource *resource = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_power_remove");
+
+	if (!device || !acpi_driver_data(device))
+		return_VALUE(-EINVAL);
+
+	resource = (struct acpi_power_resource *) acpi_driver_data(device);
+
+	acpi_power_remove_fs(device);
+
+	kfree(resource);
+
+	return_VALUE(0);
+}
+
+
+static int __init acpi_power_init (void)
+{
+	int			result = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_power_init");
+
+	if (acpi_disabled)
+		return_VALUE(0);
+
+	INIT_LIST_HEAD(&acpi_power_resource_list);
+
+	acpi_power_dir = proc_mkdir(ACPI_POWER_CLASS, acpi_root_dir);
+	if (!acpi_power_dir)
+		return_VALUE(-ENODEV);
+
+	result = acpi_bus_register_driver(&acpi_power_driver);
+	if (result < 0) {
+		remove_proc_entry(ACPI_POWER_CLASS, acpi_root_dir);
+		return_VALUE(-ENODEV);
+	}
+
+	return_VALUE(0);
+}
+
+subsys_initcall(acpi_power_init);
+