5 files changed, 748 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index da30a72a839c..12e26d772e7d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -252,6 +252,13 @@ L:	linux-acpi@vger.kernel.org
 W:      http://acpi.sourceforge.net/
 S:      Supported
 
+ACPI WMI DRIVER
+P:      Carlos Corbacho
+M:      carlos@strangeworlds.co.uk
+L:      linux-acpi@vger.kernel.org
+W:      http://www.lesswatts.org/projects/acpi/
+S:      Maintained
+
 ADM1025 HARDWARE MONITOR DRIVER
 P:      Jean Delvare
 M:      khali@linux-fr.org
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index ccf6ea95f68c..f60cf6fea2bb 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -199,6 +199,16 @@ config ACPI_NUMA
         depends on (X86 || IA64)
         default y if IA64_GENERIC || IA64_SGI_SN2
 
+config ACPI_WMI
+        tristate "WMI (EXPERIMENTAL)"
+        depends on EXPERIMENTAL
+        help
+          This driver adds support for the ACPI-WMI mapper device (PNP0C14)
+          found on some systems.
+
+          NOTE: You will need another driver or userspace application on top of
+          this to actually use anything defined in the ACPI-WMI mapper.
+
 config ACPI_ASUS
         tristate "ASUS/Medion Laptop Extras"
         depends on X86
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 456446f90077..f29812a86533 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -55,6 +55,7 @@ obj-$(CONFIG_ACPI_THERMAL)	+= thermal.o
 obj-$(CONFIG_ACPI_SYSTEM)       += system.o event.o
 obj-$(CONFIG_ACPI_DEBUG)        += debug.o
 obj-$(CONFIG_ACPI_NUMA)         += numa.o
+obj-$(CONFIG_ACPI_WMI)          += wmi.o
 obj-$(CONFIG_ACPI_ASUS)         += asus_acpi.o
 obj-$(CONFIG_ACPI_TOSHIBA)      += toshiba_acpi.o
 obj-$(CONFIG_ACPI_HOTPLUG_MEMORY)       += acpi_memhotplug.o
diff --git a/drivers/acpi/wmi.c b/drivers/acpi/wmi.c
new file mode 100644
index 000000000000..36b84ab418dd
--- /dev/null
+++ b/drivers/acpi/wmi.c
@@ -0,0 +1,710 @@
+/*
+ *  ACPI-WMI mapping driver
+ *
+ *  Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
+ *
+ *  GUID parsing code from ldm.c is:
+ *   Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
+ *   Copyright (c) 2001-2007 Anton Altaparmakov
+ *   Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.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.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/list.h>
+#include <linux/acpi.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+ACPI_MODULE_NAME("wmi");
+MODULE_AUTHOR("Carlos Corbacho");
+MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
+MODULE_LICENSE("GPL");
+
+#define ACPI_WMI_CLASS "wmi"
+
+#undef PREFIX
+#define PREFIX "ACPI: WMI: "
+
+static DEFINE_MUTEX(wmi_data_lock);
+
+struct guid_block {
+        char guid[16];
+        union {
+                char object_id[2];
+                struct {
+                        unsigned char notify_id;
+                        unsigned char reserved;
+                };
+        };
+        u8 instance_count;
+        u8 flags;
+};
+
+struct wmi_block {
+        struct list_head list;
+        struct guid_block gblock;
+        acpi_handle handle;
+        wmi_notify_handler handler;
+        void *handler_data;
+};
+
+static struct wmi_block wmi_blocks;
+
+/*
+ * If the GUID data block is marked as expensive, we must enable and
+ * explicitily disable data collection.
+ */
+#define ACPI_WMI_EXPENSIVE   0x1
+#define ACPI_WMI_METHOD      0x2        /* GUID is a method */
+#define ACPI_WMI_STRING      0x4        /* GUID takes & returns a string */
+#define ACPI_WMI_EVENT       0x8        /* GUID is an event */
+
+static int acpi_wmi_remove(struct acpi_device *device, int type);
+static int acpi_wmi_add(struct acpi_device *device);
+
+static const struct acpi_device_id wmi_device_ids[] = {
+        {"PNP0C14", 0},
+        {"pnp0c14", 0},
+        {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
+
+static struct acpi_driver acpi_wmi_driver = {
+        .name = "wmi",
+        .class = ACPI_WMI_CLASS,
+        .ids = wmi_device_ids,
+        .ops = {
+                .add = acpi_wmi_add,
+                .remove = acpi_wmi_remove,
+                },
+};
+
+/*
+ * GUID parsing functions
+ */
+
+/**
+ * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
+ * @src:  Pointer to at least 2 characters to convert.
+ *
+ * Convert a two character ASCII hex string to a number.
+ *
+ * Return:  0-255  Success, the byte was parsed correctly
+ *          -1     Error, an invalid character was supplied
+ */
+static int wmi_parse_hexbyte(const u8 *src)
+{
+        unsigned int x; /* For correct wrapping */
+        int h;
+
+        /* high part */
+        x = src[0];
+        if (x - '0' <= '9' - '0') {
+                h = x - '0';
+        } else if (x - 'a' <= 'f' - 'a') {
+                h = x - 'a' + 10;
+        } else if (x - 'A' <= 'F' - 'A') {
+                h = x - 'A' + 10;
+        } else {
+                return -1;
+        }
+        h <<= 4;
+
+        /* low part */
+        x = src[1];
+        if (x - '0' <= '9' - '0')
+                return h | (x - '0');
+        if (x - 'a' <= 'f' - 'a')
+                return h | (x - 'a' + 10);
+        if (x - 'A' <= 'F' - 'A')
+                return h | (x - 'A' + 10);
+        return -1;
+}
+
+/**
+ * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
+ * @src:   Memory block holding binary GUID (16 bytes)
+ * @dest:  Memory block to hold byte swapped binary GUID (16 bytes)
+ *
+ * Byte swap a binary GUID to match it's real GUID value
+ */
+static void wmi_swap_bytes(u8 *src, u8 *dest)
+{
+        int i;
+
+        for (i = 0; i <= 3; i++)
+                memcpy(dest + i, src + (3 - i), 1);
+
+        for (i = 0; i <= 1; i++)
+                memcpy(dest + 4 + i, src + (5 - i), 1);
+
+        for (i = 0; i <= 1; i++)
+                memcpy(dest + 6 + i, src + (7 - i), 1);
+
+        memcpy(dest + 8, src + 8, 8);
+}
+
+/**
+ * wmi_parse_guid - Convert GUID from ASCII to binary
+ * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @dest:  Memory block to hold binary GUID (16 bytes)
+ *
+ * N.B. The GUID need not be NULL terminated.
+ *
+ * Return:  'true'   @dest contains binary GUID
+ *          'false'  @dest contents are undefined
+ */
+static bool wmi_parse_guid(const u8 *src, u8 *dest)
+{
+        static const int size[] = { 4, 2, 2, 2, 6 };
+        int i, j, v;
+
+        if (src[8]  != '-' || src[13] != '-' ||
+                src[18] != '-' || src[23] != '-')
+                return false;
+
+        for (j = 0; j < 5; j++, src++) {
+                for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
+                        v = wmi_parse_hexbyte(src);
+                        if (v < 0)
+                                return false;
+                }
+        }
+
+        return true;
+}
+
+static bool find_guid(const char *guid_string, struct wmi_block **out)
+{
+        char tmp[16], guid_input[16];
+        struct wmi_block *wblock;
+        struct guid_block *block;
+        struct list_head *p;
+
+        wmi_parse_guid(guid_string, tmp);
+        wmi_swap_bytes(tmp, guid_input);
+
+        list_for_each(p, &wmi_blocks.list) {
+                wblock = list_entry(p, struct wmi_block, list);
+                block = &wblock->gblock;
+
+                if (memcmp(block->guid, guid_input, 16) == 0) {
+                        if (out)
+                                *out = wblock;
+                        return 1;
+                }
+        }
+        return 0;
+}
+
+/*
+ * Exported WMI functions
+ */
+/**
+ * wmi_evaluate_method - Evaluate a WMI method
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @instance: Instance index
+ * @method_id: Method ID to call
+ * &in: Buffer containing input for the method call
+ * &out: Empty buffer to return the method results
+ *
+ * Call an ACPI-WMI method
+ */
+acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
+u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
+{
+        struct guid_block *block = NULL;
+        struct wmi_block *wblock = NULL;
+        acpi_handle handle;
+        acpi_status status;
+        struct acpi_object_list input;
+        union acpi_object params[3];
+        char method[4] = "WM";
+
+        if (!find_guid(guid_string, &wblock))
+                return AE_BAD_ADDRESS;
+
+        block = &wblock->gblock;
+        handle = wblock->handle;
+
+        if (!block->flags & ACPI_WMI_METHOD)
+                return AE_BAD_DATA;
+
+        if (block->instance_count < instance)
+                return AE_BAD_PARAMETER;
+
+        input.count = 2;
+        input.pointer = params;
+        params[0].type = ACPI_TYPE_INTEGER;
+        params[0].integer.value = instance;
+        params[1].type = ACPI_TYPE_INTEGER;
+        params[1].integer.value = method_id;
+
+        if (in) {
+                input.count = 3;
+
+                if (block->flags & ACPI_WMI_STRING) {
+                        params[2].type = ACPI_TYPE_STRING;
+                } else {
+                        params[2].type = ACPI_TYPE_BUFFER;
+                }
+                params[2].buffer.length = in->length;
+                params[2].buffer.pointer = in->pointer;
+        }
+
+        strncat(method, block->object_id, 2);
+
+        status = acpi_evaluate_object(handle, method, &input, out);
+
+        return status;
+}
+EXPORT_SYMBOL_GPL(wmi_evaluate_method);
+
+/**
+ * wmi_query_block - Return contents of a WMI block
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @instance: Instance index
+ * &out: Empty buffer to return the contents of the data block to
+ *
+ * Return the contents of an ACPI-WMI data block to a buffer
+ */
+acpi_status wmi_query_block(const char *guid_string, u8 instance,
+struct acpi_buffer *out)
+{
+        struct guid_block *block = NULL;
+        struct wmi_block *wblock = NULL;
+        acpi_handle handle;
+        acpi_status status, wc_status = AE_ERROR;
+        struct acpi_object_list input, wc_input;
+        union acpi_object wc_params[1], wq_params[1];
+        char method[4];
+        char wc_method[4] = "WC";
+
+        if (!guid_string || !out)
+                return AE_BAD_PARAMETER;
+
+        if (!find_guid(guid_string, &wblock))
+                return AE_BAD_ADDRESS;
+
+        block = &wblock->gblock;
+        handle = wblock->handle;
+
+        if (block->instance_count < instance)
+                return AE_BAD_PARAMETER;
+
+        /* Check GUID is a data block */
+        if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
+                return AE_BAD_ADDRESS;
+
+        input.count = 1;
+        input.pointer = wq_params;
+        wq_params[0].type = ACPI_TYPE_INTEGER;
+        wq_params[0].integer.value = instance;
+
+        /*
+         * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
+         * enable collection.
+         */
+        if (block->flags & ACPI_WMI_EXPENSIVE) {
+                wc_input.count = 1;
+                wc_input.pointer = wc_params;
+                wc_params[0].type = ACPI_TYPE_INTEGER;
+                wc_params[0].integer.value = 1;
+
+                strncat(wc_method, block->object_id, 2);
+
+                /*
+                 * Some GUIDs break the specification by declaring themselves
+                 * expensive, but have no corresponding WCxx method. So we
+                 * should not fail if this happens.
+                 */
+                wc_status = acpi_evaluate_object(handle, wc_method,
+                        &wc_input, NULL);
+        }
+
+        strcpy(method, "WQ");
+        strncat(method, block->object_id, 2);
+
+        status = acpi_evaluate_object(handle, method, NULL, out);
+
+        /*
+         * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
+         * the WQxx method failed - we should disable collection anyway.
+         */
+        if ((block->flags & ACPI_WMI_EXPENSIVE) && wc_status) {
+                wc_params[0].integer.value = 0;
+                status = acpi_evaluate_object(handle,
+                wc_method, &wc_input, NULL);
+        }
+
+        return status;
+}
+EXPORT_SYMBOL_GPL(wmi_query_block);
+
+/**
+ * wmi_set_block - Write to a WMI block
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @instance: Instance index
+ * &in: Buffer containing new values for the data block
+ *
+ * Write the contents of the input buffer to an ACPI-WMI data block
+ */
+acpi_status wmi_set_block(const char *guid_string, u8 instance,
+const struct acpi_buffer *in)
+{
+        struct guid_block *block = NULL;
+        struct wmi_block *wblock = NULL;
+        acpi_handle handle;
+        struct acpi_object_list input;
+        union acpi_object params[2];
+        char method[4] = "WS";
+
+        if (!guid_string || !in)
+                return AE_BAD_DATA;
+
+        if (!find_guid(guid_string, &wblock))
+                return AE_BAD_ADDRESS;
+
+        block = &wblock->gblock;
+        handle = wblock->handle;
+
+        if (block->instance_count < instance)
+                return AE_BAD_PARAMETER;
+
+        /* Check GUID is a data block */
+        if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
+                return AE_BAD_ADDRESS;
+
+        input.count = 2;
+        input.pointer = params;
+        params[0].type = ACPI_TYPE_INTEGER;
+        params[0].integer.value = instance;
+
+        if (block->flags & ACPI_WMI_STRING) {
+                params[1].type = ACPI_TYPE_STRING;
+        } else {
+                params[1].type = ACPI_TYPE_BUFFER;
+        }
+        params[1].buffer.length = in->length;
+        params[1].buffer.pointer = in->pointer;
+
+        strncat(method, block->object_id, 2);
+
+        return acpi_evaluate_object(handle, method, &input, NULL);
+}
+EXPORT_SYMBOL_GPL(wmi_set_block);
+
+/**
+ * wmi_install_notify_handler - Register handler for WMI events
+ * @handler: Function to handle notifications
+ * @data: Data to be returned to handler when event is fired
+ *
+ * Register a handler for events sent to the ACPI-WMI mapper device.
+ */
+acpi_status wmi_install_notify_handler(const char *guid,
+wmi_notify_handler handler, void *data)
+{
+        struct wmi_block *block;
+
+        if (!guid || !handler)
+                return AE_BAD_PARAMETER;
+
+        find_guid(guid, &block);
+        if (!block)
+                return AE_NOT_EXIST;
+
+        if (block->handler)
+                return AE_ALREADY_ACQUIRED;
+
+        block->handler = handler;
+        block->handler_data = data;
+
+        return AE_OK;
+}
+EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
+
+/**
+ * wmi_uninstall_notify_handler - Unregister handler for WMI events
+ *
+ * Unregister handler for events sent to the ACPI-WMI mapper device.
+ */
+acpi_status wmi_remove_notify_handler(const char *guid)
+{
+        struct wmi_block *block;
+
+        if (!guid)
+                return AE_BAD_PARAMETER;
+
+        find_guid(guid, &block);
+        if (!block)
+                return AE_NOT_EXIST;
+
+        if (!block->handler)
+                return AE_NULL_ENTRY;
+
+        block->handler = NULL;
+        block->handler_data = NULL;
+
+        return AE_OK;
+}
+EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
+
+/**
+ * wmi_get_event_data - Get WMI data associated with an event
+ *
+ * @event - Event to find
+ * &out - Buffer to hold event data
+ *
+ * Returns extra data associated with an event in WMI.
+ */
+acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
+{
+        struct acpi_object_list input;
+        union acpi_object params[1];
+        struct guid_block *gblock;
+        struct wmi_block *wblock;
+        struct list_head *p;
+
+        input.count = 1;
+        input.pointer = params;
+        params[0].type = ACPI_TYPE_INTEGER;
+        params[0].integer.value = event;
+
+        list_for_each(p, &wmi_blocks.list) {
+                wblock = list_entry(p, struct wmi_block, list);
+                gblock = &wblock->gblock;
+
+                if ((gblock->flags & ACPI_WMI_EVENT) &&
+                        (gblock->notify_id == event))
+                        return acpi_evaluate_object(wblock->handle, "_WED",
+                                &input, out);
+        }
+
+        return AE_NOT_FOUND;
+}
+EXPORT_SYMBOL_GPL(wmi_get_event_data);
+
+/**
+ * wmi_has_guid - Check if a GUID is available
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ *
+ * Check if a given GUID is defined by _WDG
+ */
+bool wmi_has_guid(const char *guid_string)
+{
+        return find_guid(guid_string, NULL);
+}
+EXPORT_SYMBOL_GPL(wmi_has_guid);
+
+/*
+ * Parse the _WDG method for the GUID data blocks
+ */
+static __init acpi_status parse_wdg(acpi_handle handle)
+{
+        struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
+        union acpi_object *obj;
+        struct guid_block *gblock;
+        struct wmi_block *wblock;
+        acpi_status status;
+        u32 i, total;
+
+        status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
+
+        if (ACPI_FAILURE(status))
+                return status;
+
+        obj = (union acpi_object *) out.pointer;
+
+        if (obj->type != ACPI_TYPE_BUFFER)
+                return AE_ERROR;
+
+        total = obj->buffer.length / sizeof(struct guid_block);
+
+        gblock = kzalloc(obj->buffer.length, GFP_KERNEL);
+        if (!gblock)
+                return AE_NO_MEMORY;
+
+        memcpy(gblock, obj->buffer.pointer, obj->buffer.length);
+
+        for (i = 0; i < total; i++) {
+                wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
+                if (!wblock)
+                        return AE_NO_MEMORY;
+
+                wblock->gblock = gblock[i];
+                wblock->handle = handle;
+                list_add_tail(&wblock->list, &wmi_blocks.list);
+        }
+
+        kfree(out.pointer);
+        kfree(gblock);
+
+        return status;
+}
+
+/*
+ * WMI can have EmbeddedControl access regions. In which case, we just want to
+ * hand these off to the EC driver.
+ */
+static acpi_status
+acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
+                      u32 bits, acpi_integer * value,
+                      void *handler_context, void *region_context)
+{
+        int result = 0, i = 0;
+        u8 temp = 0;
+
+        if ((address > 0xFF) || !value)
+                return AE_BAD_PARAMETER;
+
+        if (function != ACPI_READ && function != ACPI_WRITE)
+                return AE_BAD_PARAMETER;
+
+        if (bits != 8)
+                return AE_BAD_PARAMETER;
+
+        if (function == ACPI_READ) {
+                result = ec_read(address, &temp);
+                (*value) |= ((acpi_integer)temp) << i;
+        } else {
+                temp = 0xff & ((*value) >> i);
+                result = ec_write(address, temp);
+        }
+
+        switch (result) {
+        case -EINVAL:
+                return AE_BAD_PARAMETER;
+                break;
+        case -ENODEV:
+                return AE_NOT_FOUND;
+                break;
+        case -ETIME:
+                return AE_TIME;
+                break;
+        default:
+                return AE_OK;
+        }
+}
+
+static void acpi_wmi_notify(acpi_handle handle, u32 event, void *data)
+{
+        struct guid_block *block;
+        struct wmi_block *wblock;
+        struct list_head *p;
+        struct acpi_device *device = data;
+
+        list_for_each(p, &wmi_blocks.list) {
+                wblock = list_entry(p, struct wmi_block, list);
+                block = &wblock->gblock;
+
+                if ((block->flags & ACPI_WMI_EVENT) &&
+                        (block->notify_id == event)) {
+                        if (wblock->handler)
+                                wblock->handler(event, wblock->handler_data);
+
+                        acpi_bus_generate_netlink_event(
+                                device->pnp.device_class, device->dev.bus_id,
+                                event, 0);
+                        break;
+                }
+        }
+}
+
+static int acpi_wmi_remove(struct acpi_device *device, int type)
+{
+        acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+                acpi_wmi_notify);
+
+        acpi_remove_address_space_handler(device->handle,
+                                ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
+
+        return 0;
+}
+
+static int __init acpi_wmi_add(struct acpi_device *device)
+{
+        acpi_status status;
+        int result = 0;
+
+        status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
+                acpi_wmi_notify, device);
+        if (ACPI_FAILURE(status)) {
+                printk(KERN_ERR PREFIX "Error installing notify handler\n");
+                return -ENODEV;
+        }
+
+        status = acpi_install_address_space_handler(device->handle,
+                                                    ACPI_ADR_SPACE_EC,
+                                                    &acpi_wmi_ec_space_handler,
+                                                    NULL, NULL);
+        if (ACPI_FAILURE(status))
+                return -ENODEV;
+
+        status = parse_wdg(device->handle);
+        if (ACPI_FAILURE(status)) {
+                printk(KERN_ERR PREFIX "Error installing EC region handler\n");
+                return -ENODEV;
+        }
+
+        return result;
+}
+
+static int __init acpi_wmi_init(void)
+{
+        acpi_status result;
+
+        if (acpi_disabled)
+                return -ENODEV;
+
+        INIT_LIST_HEAD(&wmi_blocks.list);
+
+        result = acpi_bus_register_driver(&acpi_wmi_driver);
+
+        if (result < 0) {
+                printk(KERN_INFO PREFIX "Error loading mapper\n");
+        } else {
+                printk(KERN_INFO PREFIX "Mapper loaded\n");
+        }
+
+        return result;
+}
+
+static void __exit acpi_wmi_exit(void)
+{
+        struct list_head *p, *tmp;
+        struct wmi_block *wblock;
+
+        acpi_bus_unregister_driver(&acpi_wmi_driver);
+
+        list_for_each_safe(p, tmp, &wmi_blocks.list) {
+                wblock = list_entry(p, struct wmi_block, list);
+
+                list_del(p);
+                kfree(wblock);
+        }
+
+        printk(KERN_INFO PREFIX "Mapper unloaded\n");
+}
+
+subsys_initcall(acpi_wmi_init);
+module_exit(acpi_wmi_exit);
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 63f2e6ed698f..fab9f70fe39d 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -192,6 +192,26 @@ extern int ec_transaction(u8 command,
 
 #endif /*CONFIG_ACPI_EC*/
 
+#if defined(CONFIG_ACPI_WMI) || defined(CONFIG_ACPI_WMI_MODULE)
+
+typedef void (*wmi_notify_handler) (u32 value, void *context);
+
+extern acpi_status wmi_evaluate_method(const char *guid, u8 instance,
+                                        u32 method_id,
+                                        const struct acpi_buffer *in,
+                                        struct acpi_buffer *out);
+extern acpi_status wmi_query_block(const char *guid, u8 instance,
+                                        struct acpi_buffer *out);
+extern acpi_status wmi_set_block(const char *guid, u8 instance,
+                                        const struct acpi_buffer *in);
+extern acpi_status wmi_install_notify_handler(const char *guid,
+                                        wmi_notify_handler handler, void *data);
+extern acpi_status wmi_remove_notify_handler(const char *guid);
+extern acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out);
+extern bool wmi_has_guid(const char *guid);
+
+#endif  /* CONFIG_ACPI_WMI */
+
 extern int acpi_blacklisted(void);
 #ifdef CONFIG_DMI
 extern void acpi_dmi_osi_linux(int enable, const struct dmi_system_id *d);