/*
* Dell WMI hotkeys
*
* Copyright (C) 2008 Red Hat <mjg@redhat.com>
* Copyright (C) 2014-2015 Pali Rohár <pali.rohar@gmail.com>
*
* Portions based on wistron_btns.c:
* Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
* Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
* Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
*
* 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
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/input.h>
#include <linux/input/sparse-keymap.h>
#include <linux/acpi.h>
#include <linux/string.h>
#include <linux/dmi.h>
#include <acpi/video.h>
#include "dell-smbios.h"
MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
MODULE_LICENSE("GPL");
#define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
#define DELL_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492"
static u32 dell_wmi_interface_version;
static bool wmi_requires_smbios_request;
MODULE_ALIAS("wmi:"DELL_EVENT_GUID);
MODULE_ALIAS("wmi:"DELL_DESCRIPTOR_GUID);
static int __init dmi_matched(const struct dmi_system_id *dmi)
{
wmi_requires_smbios_request = 1;
return 1;
}
static const struct dmi_system_id dell_wmi_smbios_list[] __initconst = {
{
.callback = dmi_matched,
.ident = "Dell Inspiron M5110",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron M5110"),
},
},
{
.callback = dmi_matched,
.ident = "Dell Vostro V131",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
},
},
{ }
};
/*
* Keymap for WMI events of type 0x0000
*
* Certain keys are flagged as KE_IGNORE. All of these are either
* notifications (rather than requests for change) or are also sent
* via the keyboard controller so should not be sent again.
*/
static const struct key_entry dell_wmi_keymap_type_0000[] __initconst = {
{ KE_IGNORE, 0x003a, { KEY_CAPSLOCK } },
/* Key code is followed by brightness level */
{ KE_KEY, 0xe005, { KEY_BRIGHTNESSDOWN } },
{ KE_KEY, 0xe006, { KEY_BRIGHTNESSUP } },
/* Battery health status button */
{ KE_KEY, 0xe007, { KEY_BATTERY } },
/* Radio devices state change, key code is followed by other values */
{ KE_IGNORE, 0xe008, { KEY_RFKILL } },
{ KE_KEY, 0xe009, { KEY_EJECTCD } },
/* Key code is followed by: next, active and attached devices */
{ KE_KEY, 0xe00b, { KEY_SWITCHVIDEOMODE } },
/* Key code is followed by keyboard illumination level */
{ KE_IGNORE, 0xe00c, { KEY_KBDILLUMTOGGLE } },
/* BIOS error detected */
{ KE_IGNORE, 0xe00d, { KEY_RESERVED } },
/* Battery was removed or inserted */
{ KE_IGNORE, 0xe00e, { KEY_RESERVED } },
/* Wifi Catcher */
{ KE_KEY, 0xe011, { KEY_WLAN } },
/* Ambient light sensor toggle */
{ KE_IGNORE, 0xe013, { KEY_RESERVED } },
{ KE_IGNORE, 0xe020, { KEY_MUTE } },
/* Unknown, defined in ACPI DSDT */
/* { KE_IGNORE, 0xe023, { KEY_RESERVED } }, */
/* Untested, Dell Instant Launch key on Inspiron 7520 */
/* { KE_IGNORE, 0xe024, { KEY_RESERVED } }, */
/* Dell Instant Launch key */
{ KE_KEY, 0xe025, { KEY_PROG4 } },
/* Audio panel key */
{ KE_IGNORE, 0xe026, { KEY_RESERVED } },
/* LCD Display On/Off Control key */
{ KE_KEY, 0xe027, { KEY_DISPLAYTOGGLE } },
/* Untested, Multimedia key on Dell Vostro 3560 */
/* { KE_IGNORE, 0xe028, { KEY_RESERVED } }, */
/* Dell Instant Launch key */
{ KE_KEY, 0xe029, { KEY_PROG4 } },
/* Untested, Windows Mobility Center button on Inspiron 7520 */
/* { KE_IGNORE, 0xe02a, { KEY_RESERVED } }, */
/* Unknown, defined in ACPI DSDT */
/* { KE_IGNORE, 0xe02b, { KEY_RESERVED } }, */
/* Untested, Dell Audio With Preset Switch button on Inspiron 7520 */
/* { KE_IGNORE, 0xe02c, { KEY_RESERVED } }, */
{ KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
{ KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
{ KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
{ KE_IGNORE, 0xe034, { KEY_KBDILLUMDOWN } },
{ KE_IGNORE, 0xe03a, { KEY_CAPSLOCK } },
/* NIC Link is Up */
{ KE_IGNORE, 0xe043, { KEY_RESERVED } },
/* NIC Link is Down */
{ KE_IGNORE, 0xe044, { KEY_RESERVED } },
/*
* This entry is very suspicious!
* Originally Matthew Garrett created this dell-wmi driver specially for
* "button with a picture of a battery" which has event code 0xe045.
* Later Mario Limonciello from Dell told us that event code 0xe045 is
* reported by Num Lock and should be ignored because key is send also
* by keyboard controller.
* So for now we will ignore this event to prevent potential double
* Num Lock key press.
*/
{ KE_IGNORE, 0xe045, { KEY_NUMLOCK } },
/* Scroll lock and also going to tablet mode on portable devices */
{ KE_IGNORE, 0xe046, { KEY_SCROLLLOCK } },
/* Untested, going from tablet mode on portable devices */
/* { KE_IGNORE, 0xe047, { KEY_RESERVED } }, */
/* Dell Support Center key */
{ KE_IGNORE, 0xe06e, { KEY_RESERVED } },
{ KE_IGNORE, 0xe0f7, { KEY_MUTE } },
{ KE_IGNORE, 0xe0f8, { KEY_VOLUMEDOWN } },
{ KE_IGNORE, 0xe0f9, { KEY_VOLUMEUP } },
};
struct dell_bios_keymap_entry {
u16 scancode;
u16 keycode;
};
struct dell_bios_hotkey_table {
struct dmi_header header;
struct dell_bios_keymap_entry keymap[];
};
struct dell_dmi_results {
int err;
int keymap_size;
struct key_entry *keymap;
};
/* Uninitialized entries here are KEY_RESERVED == 0. */
static const u16 bios_to_linux_keycode[256] __initconst = {
[0] = KEY_MEDIA,
[1] = KEY_NEXTSONG,
[2] = KEY_PLAYPAUSE,
[3] = KEY_PREVIOUSSONG,
[4] = KEY_STOPCD,
[5] = KEY_UNKNOWN,
[6] = KEY_UNKNOWN,
[7] = KEY_UNKNOWN,
[8] = KEY_WWW,
[9] = KEY_UNKNOWN,
[10] = KEY_VOLUMEDOWN,
[11] = KEY_MUTE,
[12] = KEY_VOLUMEUP,
[13] = KEY_UNKNOWN,
[14] = KEY_BATTERY,
[15] = KEY_EJECTCD,
[16] = KEY_UNKNOWN,
[17] = KEY_SLEEP,
[18] = KEY_PROG1,
[19] = KEY_BRIGHTNESSDOWN,
[20] = KEY_BRIGHTNESSUP,
[21] = KEY_UNKNOWN,
[22] = KEY_KBDILLUMTOGGLE,
[23] = KEY_UNKNOWN,
[24] = KEY_SWITCHVIDEOMODE,
[25] = KEY_UNKNOWN,
[26] = KEY_UNKNOWN,
[27] = KEY_SWITCHVIDEOMODE,
[28] = KEY_UNKNOWN,
[29] = KEY_UNKNOWN,
[30] = KEY_PROG2,
[31] = KEY_UNKNOWN,
[32] = KEY_UNKNOWN,
[33] = KEY_UNKNOWN,
[34] = KEY_UNKNOWN,
[35] = KEY_UNKNOWN,
[36] = KEY_UNKNOWN,
[37] = KEY_UNKNOWN,
[38] = KEY_MICMUTE,
[255] = KEY_PROG3,
};
/*
* Keymap for WMI events of type 0x0010
*
* These are applied if the 0xB2 DMI hotkey table is present and doesn't
* override them.
*/
static const struct key_entry dell_wmi_keymap_type_0010[] __initconst = {
/* Fn-lock */
{ KE_IGNORE, 0x151, { KEY_RESERVED } },
/* Change keyboard illumination */
{ KE_IGNORE, 0x152, { KEY_KBDILLUMTOGGLE } },
/*
* Radio disable (notify only -- there is no model for which the
* WMI event is supposed to trigger an action).
*/
{ KE_IGNORE, 0x153, { KEY_RFKILL } },
/* RGB keyboard backlight control */
{ KE_IGNORE, 0x154, { KEY_RESERVED } },
/* Stealth mode toggle */
{ KE_IGNORE, 0x155, { KEY_RESERVED } },
/* Rugged magnetic dock attach/detach events */
{ KE_IGNORE, 0x156, { KEY_RESERVED } },
{ KE_IGNORE, 0x157, { KEY_RESERVED } },
/* Rugged programmable (P1/P2/P3 keys) */
{ KE_KEY, 0x850, { KEY_PROG1 } },
{ KE_KEY, 0x851, { KEY_PROG2 } },
{ KE_KEY, 0x852, { KEY_PROG3 } },
};
/*
* Keymap for WMI events of type 0x0011
*/
static const struct key_entry dell_wmi_keymap_type_0011[] __initconst = {
/* Battery unplugged */
{ KE_IGNORE, 0xfff0, { KEY_RESERVED } },
/* Battery inserted */
{ KE_IGNORE, 0xfff1, { KEY_RESERVED } },
/* Keyboard backlight level changed */
{ KE_IGNORE, 0x01e1, { KEY_RESERVED } },
{ KE_IGNORE, 0x02ea, { KEY_RESERVED } },
{ KE_IGNORE, 0x02eb, { KEY_RESERVED } },
{ KE_IGNORE, 0x02ec, { KEY_RESERVED } },
{ KE_IGNORE, 0x02f6, { KEY_RESERVED } },
};
static struct input_dev *dell_wmi_input_dev;
static void dell_wmi_process_key(int type, int code)
{
const struct key_entry *key;
key = sparse_keymap_entry_from_scancode(dell_wmi_input_dev,
(type << 16) | code);
if (!key) {
pr_info("Unknown key with type 0x%04x and code 0x%04x pressed\n",
type, code);
return;
}
pr_debug("Key with type 0x%04x and code 0x%04x pressed\n", type, code);
/* Don't report brightness notifications that will also come via ACPI */
if ((key->keycode == KEY_BRIGHTNESSUP ||
key->keycode == KEY_BRIGHTNESSDOWN) &&
acpi_video_handles_brightness_key_presses())
return;
if (type == 0x0000 && code == 0xe025 && !wmi_requires_smbios_request)
return;
sparse_keymap_report_entry(dell_wmi_input_dev, key, 1, true);
}
static void dell_wmi_notify(u32 value, void *context)
{
struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
acpi_size buffer_size;
u16 *buffer_entry, *buffer_end;
int len, i;
status = wmi_get_event_data(value, &response);
if (status != AE_OK) {
pr_warn("bad event status 0x%x\n", status);
return;
}
obj = (union acpi_object *)response.pointer;
if (!obj) {
pr_warn("no response\n");
return;
}
if (obj->type != ACPI_TYPE_BUFFER) {
pr_warn("bad response type %x\n", obj->type);
kfree(obj);
return;
}
pr_debug("Received WMI event (%*ph)\n",
obj->buffer.length, obj->buffer.pointer);
buffer_entry = (u16 *)obj->buffer.pointer;
buffer_size = obj->buffer.length/2;
buffer_end = buffer_entry + buffer_size;
/*
* BIOS/ACPI on devices with WMI interface version 0 does not clear
* buffer before filling it. So next time when BIOS/ACPI send WMI event
* which is smaller as previous then it contains garbage in buffer from
* previous event.
*
* BIOS/ACPI on devices with WMI interface version 1 clears buffer and
* sometimes send more events in buffer at one call.
*
* So to prevent reading garbage from buffer we will process only first
* one event on devices with WMI interface version 0.
*/
if (dell_wmi_interface_version == 0 && buffer_entry < buffer_end)
if (buffer_end > buffer_entry + buffer_entry[0] + 1)
buffer_end = buffer_entry + buffer_entry[0] + 1;
while (buffer_entry < buffer_end) {
len = buffer_entry[0];
if (len == 0)
break;
len++;
if (buffer_entry + len > buffer_end) {
pr_warn("Invalid length of WMI event\n");
break;
}
pr_debug("Process buffer (%*ph)\n", len*2, buffer_entry);
switch (buffer_entry[1]) {
case 0x0000: /* One key pressed or event occurred */
if (len > 2)
dell_wmi_process_key(0x0000, buffer_entry[2]);
/* Other entries could contain additional information */
break;
case 0x0010: /* Sequence of keys pressed */
case 0x0011: /* Sequence of events occurred */
for (i = 2; i < len; ++i)
dell_wmi_process_key(buffer_entry[1],
buffer_entry[i]);
break;
default: /* Unknown event */
pr_info("Unknown WMI event type 0x%x\n",
(int)buffer_entry[1]);
break;
}
buffer_entry += len;
}
kfree(obj);
}
static bool have_scancode(u32 scancode, const struct key_entry *keymap, int len)
{
int i;
for (i = 0; i < len; i++)
if (keymap[i].code == scancode)
return true;
return false;
}
static void __init handle_dmi_entry(const struct dmi_header *dm,
void *opaque)
{
struct dell_dmi_results *results = opaque;
struct dell_bios_hotkey_table *table;
int hotkey_num, i, pos = 0;
struct key_entry *keymap;
if (results->err || results->keymap)
return; /* We already found the hotkey table. */
if (dm->type != 0xb2)
return;
table = container_of(dm, struct dell_bios_hotkey_table, header);
hotkey_num = (table->header.length -
sizeof(struct dell_bios_hotkey_table)) /
sizeof(struct dell_bios_keymap_entry);
if (hotkey_num < 1) {
/*
* Historically, dell-wmi would ignore a DMI entry of
* fewer than 7 bytes. Sizes between 4 and 8 bytes are
* nonsensical (both the header and all entries are 4
* bytes), so we approximate the old behavior by
* ignoring tables with fewer than one entry.
*/
return;
}
keymap = kcalloc(hotkey_num, sizeof(struct key_entry), GFP_KERNEL);
if (!keymap) {
results->err = -ENOMEM;
return;
}
for (i = 0; i < hotkey_num; i++) {
const struct dell_bios_keymap_entry *bios_entry =
&table->keymap[i];
/* Uninitialized entries are 0 aka KEY_RESERVED. */
u16 keycode = (bios_entry->keycode <
ARRAY_SIZE(bios_to_linux_keycode)) ?
bios_to_linux_keycode[bios_entry->keycode] :
KEY_RESERVED;
/*
* Log if we find an entry in the DMI table that we don't
* understand. If this happens, we should figure out what
* the entry means and add it to bios_to_linux_keycode.
*/
if (keycode == KEY_RESERVED) {
pr_info("firmware scancode 0x%x maps to unrecognized keycode 0x%x\n",
bios_entry->scancode, bios_entry->keycode);
continue;
}
if (keycode == KEY_KBDILLUMTOGGLE)
keymap[pos].type = KE_IGNORE;
else
keymap[pos].type = KE_KEY;
keymap[pos].code = bios_entry->scancode;
keymap[pos].keycode = keycode;
pos++;
}
results->keymap = keymap;
results->keymap_size = pos;
}
static int __init dell_wmi_input_setup(void)
{
struct dell_dmi_results dmi_results = {};
struct key_entry *keymap;
int err, i, pos = 0;
dell_wmi_input_dev = input_allocate_device();
if (!dell_wmi_input_dev)
return -ENOMEM;
dell_wmi_input_dev->name = "Dell WMI hotkeys";
dell_wmi_input_dev->phys = "wmi/input0";
dell_wmi_input_dev->id.bustype = BUS_HOST;
if (dmi_walk(handle_dmi_entry, &dmi_results)) {
/*
* Historically, dell-wmi ignored dmi_walk errors. A failure
* is certainly surprising, but it probably just indicates
* a very old laptop.
*/
pr_warn("no DMI; using the old-style hotkey interface\n");
}
if (dmi_results.err) {
err = dmi_results.err;
goto err_free_dev;
}
keymap = kcalloc(dmi_results.keymap_size +
ARRAY_SIZE(dell_wmi_keymap_type_0000) +
ARRAY_SIZE(dell_wmi_keymap_type_0010) +
ARRAY_SIZE(dell_wmi_keymap_type_0011) +
1,
sizeof(struct key_entry), GFP_KERNEL);
if (!keymap) {
kfree(dmi_results.keymap);
err = -ENOMEM;
goto err_free_dev;
}
/* Append table with events of type 0x0010 which comes from DMI */
for (i = 0; i < dmi_results.keymap_size; i++) {
keymap[pos] = dmi_results.keymap[i];
keymap[pos].code |= (0x0010 << 16);
pos++;
}
kfree(dmi_results.keymap);
/* Append table with extra events of type 0x0010 which are not in DMI */
for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0010); i++) {
const struct key_entry *entry = &dell_wmi_keymap_type_0010[i];
/*
* Check if we've already found this scancode. This takes
* quadratic time, but it doesn't matter unless the list
* of extra keys gets very long.
*/
if (dmi_results.keymap_size &&
have_scancode(entry->code | (0x0010 << 16),
keymap, dmi_results.keymap_size)
)
continue;
keymap[pos] = *entry;
keymap[pos].code |= (0x0010 << 16);
pos++;
}
/* Append table with events of type 0x0011 */
for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0011); i++) {
keymap[pos] = dell_wmi_keymap_type_0011[i];
keymap[pos].code |= (0x0011 << 16);
pos++;
}
/*
* Now append also table with "legacy" events of type 0x0000. Some of
* them are reported also on laptops which have scancodes in DMI.
*/
for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0000); i++) {
keymap[pos] = dell_wmi_keymap_type_0000[i];
pos++;
}
keymap[pos].type = KE_END;
err = sparse_keymap_setup(dell_wmi_input_dev, keymap, NULL);
/*
* Sparse keymap library makes a copy of keymap so we don't need the
* original one that was allocated.
*/
kfree(keymap);
if (err)
goto err_free_dev;
err = input_register_device(dell_wmi_input_dev);
if (err)
goto err_free_keymap;
return 0;
err_free_keymap:
sparse_keymap_free(dell_wmi_input_dev);
err_free_dev:
input_free_device(dell_wmi_input_dev);
return err;
}
static void dell_wmi_input_destroy(void)
{
sparse_keymap_free(dell_wmi_input_dev);
input_unregister_device(dell_wmi_input_dev);
}
/*
* Descriptor buffer is 128 byte long and contains:
*
* Name Offset Length Value
* Vendor Signature 0 4 "DELL"
* Object Signature 4 4 " WMI"
* WMI Interface Version 8 4 <version>
* WMI buffer length 12 4 4096
*/
static int __init dell_wmi_check_descriptor_buffer(void)
{
struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
u32 *buffer;
status = wmi_query_block(DELL_DESCRIPTOR_GUID, 0, &out);
if (ACPI_FAILURE(status)) {
pr_err("Cannot read Dell descriptor buffer - %d\n", status);
return status;
}
obj = (union acpi_object *)out.pointer;
if (!obj) {
pr_err("Dell descriptor buffer is empty\n");
return -EINVAL;
}
if (obj->type != ACPI_TYPE_BUFFER) {
pr_err("Cannot read Dell descriptor buffer\n");
kfree(obj);
return -EINVAL;
}
if (obj->buffer.length != 128) {
pr_err("Dell descriptor buffer has invalid length (%d)\n",
obj->buffer.length);
if (obj->buffer.length < 16) {
kfree(obj);
return -EINVAL;
}
}
buffer = (u32 *)obj->buffer.pointer;
if (buffer[0] != 0x4C4C4544 && buffer[1] != 0x494D5720)
pr_warn("Dell descriptor buffer has invalid signature (%*ph)\n",
8, buffer);
if (buffer[2] != 0 && buffer[2] != 1)
pr_warn("Dell descriptor buffer has unknown version (%d)\n",
buffer[2]);
if (buffer[3] != 4096)
pr_warn("Dell descriptor buffer has invalid buffer length (%d)\n",
buffer[3]);
dell_wmi_interface_version = buffer[2];
pr_info("Detected Dell WMI interface version %u\n",
dell_wmi_interface_version);
kfree(obj);
return 0;
}
/*
* According to Dell SMBIOS documentation:
*
* 17 3 Application Program Registration
*
* cbArg1 Application ID 1 = 0x00010000
* cbArg2 Application ID 2
* QUICKSET/DCP = 0x51534554 "QSET"
* ALS Driver = 0x416c7353 "AlsS"
* Latitude ON = 0x4c6f6e52 "LonR"
* cbArg3 Application version or revision number
* cbArg4 0 = Unregister application
* 1 = Register application
* cbRes1 Standard return codes (0, -1, -2)
*/
static int dell_wmi_events_set_enabled(bool enable)
{
struct calling_interface_buffer *buffer;
int ret;
buffer = dell_smbios_get_buffer();
buffer->input[0] = 0x10000;
buffer->input[1] = 0x51534554;
buffer->input[3] = enable;
dell_smbios_send_request(17, 3);
ret = buffer->output[0];
dell_smbios_release_buffer();
return dell_smbios_error(ret);
}
static int __init dell_wmi_init(void)
{
int err;
acpi_status status;
if (!wmi_has_guid(DELL_EVENT_GUID) ||
!wmi_has_guid(DELL_DESCRIPTOR_GUID)) {
pr_warn("Dell WMI GUID were not found\n");
return -ENODEV;
}
err = dell_wmi_check_descriptor_buffer();
if (err)
return err;
err = dell_wmi_input_setup();
if (err)
return err;
status = wmi_install_notify_handler(DELL_EVENT_GUID,
dell_wmi_notify, NULL);
if (ACPI_FAILURE(status)) {
dell_wmi_input_destroy();
pr_err("Unable to register notify handler - %d\n", status);
return -ENODEV;
}
dmi_check_system(dell_wmi_smbios_list);
if (wmi_requires_smbios_request) {
err = dell_wmi_events_set_enabled(true);
if (err) {
pr_err("Failed to enable WMI events\n");
wmi_remove_notify_handler(DELL_EVENT_GUID);
dell_wmi_input_destroy();
return err;
}
}
return 0;
}
module_init(dell_wmi_init);
static void __exit dell_wmi_exit(void)
{
if (wmi_requires_smbios_request)
dell_wmi_events_set_enabled(false);
wmi_remove_notify_handler(DELL_EVENT_GUID);
dell_wmi_input_destroy();
}
module_exit(dell_wmi_exit);