blob: 23ebd0c046e16dcf447e2f4463c74618cbf46510 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Huawei WMI laptop extras driver
*
* Copyright (C) 2018 Ayman Bagabas <ayman.bagabas@gmail.com>
*/
#include <linux/acpi.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/input.h>
#include <linux/input/sparse-keymap.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/sysfs.h>
#include <linux/wmi.h>
#include <acpi/battery.h>
/*
* Huawei WMI GUIDs
*/
#define HWMI_METHOD_GUID "ABBC0F5B-8EA1-11D1-A000-C90629100000"
#define HWMI_EVENT_GUID "ABBC0F5C-8EA1-11D1-A000-C90629100000"
/* Legacy GUIDs */
#define WMI0_EXPENSIVE_GUID "39142400-C6A3-40fa-BADB-8A2652834100"
#define WMI0_EVENT_GUID "59142400-C6A3-40fa-BADB-8A2652834100"
/* HWMI commands */
enum {
BATTERY_THRESH_GET = 0x00001103, /* \GBTT */
BATTERY_THRESH_SET = 0x00001003, /* \SBTT */
FN_LOCK_GET = 0x00000604, /* \GFRS */
FN_LOCK_SET = 0x00000704, /* \SFRS */
MICMUTE_LED_SET = 0x00000b04, /* \SMLS */
};
union hwmi_arg {
u64 cmd;
u8 args[8];
};
struct quirk_entry {
bool battery_reset;
bool ec_micmute;
bool report_brightness;
};
static struct quirk_entry *quirks;
struct huawei_wmi_debug {
struct dentry *root;
u64 arg;
};
struct huawei_wmi {
bool battery_available;
bool fn_lock_available;
struct huawei_wmi_debug debug;
struct input_dev *idev[2];
struct led_classdev cdev;
struct device *dev;
struct mutex wmi_lock;
};
static struct huawei_wmi *huawei_wmi;
static const struct key_entry huawei_wmi_keymap[] = {
{ KE_KEY, 0x281, { KEY_BRIGHTNESSDOWN } },
{ KE_KEY, 0x282, { KEY_BRIGHTNESSUP } },
{ KE_KEY, 0x284, { KEY_MUTE } },
{ KE_KEY, 0x285, { KEY_VOLUMEDOWN } },
{ KE_KEY, 0x286, { KEY_VOLUMEUP } },
{ KE_KEY, 0x287, { KEY_MICMUTE } },
{ KE_KEY, 0x289, { KEY_WLAN } },
// Huawei |M| key
{ KE_KEY, 0x28a, { KEY_CONFIG } },
// Keyboard backlit
{ KE_IGNORE, 0x293, { KEY_KBDILLUMTOGGLE } },
{ KE_IGNORE, 0x294, { KEY_KBDILLUMUP } },
{ KE_IGNORE, 0x295, { KEY_KBDILLUMUP } },
// Ignore Ambient Light Sensoring
{ KE_KEY, 0x2c1, { KEY_RESERVED } },
{ KE_END, 0 }
};
static int battery_reset = -1;
static int report_brightness = -1;
module_param(battery_reset, bint, 0444);
MODULE_PARM_DESC(battery_reset,
"Reset battery charge values to (0-0) before disabling it using (0-100)");
module_param(report_brightness, bint, 0444);
MODULE_PARM_DESC(report_brightness,
"Report brightness keys.");
/* Quirks */
static int __init dmi_matched(const struct dmi_system_id *dmi)
{
quirks = dmi->driver_data;
return 1;
}
static struct quirk_entry quirk_unknown = {
};
static struct quirk_entry quirk_battery_reset = {
.battery_reset = true,
};
static struct quirk_entry quirk_matebook_x = {
.ec_micmute = true,
.report_brightness = true,
};
static const struct dmi_system_id huawei_quirks[] = {
{
.callback = dmi_matched,
.ident = "Huawei MACH-WX9",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
DMI_MATCH(DMI_PRODUCT_NAME, "MACH-WX9"),
},
.driver_data = &quirk_battery_reset
},
{
.callback = dmi_matched,
.ident = "Huawei MateBook X",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
DMI_MATCH(DMI_PRODUCT_NAME, "HUAWEI MateBook X")
},
.driver_data = &quirk_matebook_x
},
{ }
};
/* Utils */
static int huawei_wmi_call(struct huawei_wmi *huawei,
struct acpi_buffer *in, struct acpi_buffer *out)
{
acpi_status status;
mutex_lock(&huawei->wmi_lock);
status = wmi_evaluate_method(HWMI_METHOD_GUID, 0, 1, in, out);
mutex_unlock(&huawei->wmi_lock);
if (ACPI_FAILURE(status)) {
dev_err(huawei->dev, "Failed to evaluate wmi method\n");
return -ENODEV;
}
return 0;
}
/* HWMI takes a 64 bit input and returns either a package with 2 buffers, one of
* 4 bytes and the other of 256 bytes, or one buffer of size 0x104 (260) bytes.
* The first 4 bytes are ignored, we ignore the first 4 bytes buffer if we got a
* package, or skip the first 4 if a buffer of 0x104 is used. The first byte of
* the remaining 0x100 sized buffer has the return status of every call. In case
* the return status is non-zero, we return -ENODEV but still copy the returned
* buffer to the given buffer parameter (buf).
*/
static int huawei_wmi_cmd(u64 arg, u8 *buf, size_t buflen)
{
struct huawei_wmi *huawei = huawei_wmi;
struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_buffer in;
union acpi_object *obj;
size_t len;
int err, i;
in.length = sizeof(arg);
in.pointer = &arg;
/* Some models require calling HWMI twice to execute a command. We evaluate
* HWMI and if we get a non-zero return status we evaluate it again.
*/
for (i = 0; i < 2; i++) {
err = huawei_wmi_call(huawei, &in, &out);
if (err)
goto fail_cmd;
obj = out.pointer;
if (!obj) {
err = -EIO;
goto fail_cmd;
}
switch (obj->type) {
/* Models that implement both "legacy" and HWMI tend to return a 0x104
* sized buffer instead of a package of 0x4 and 0x100 buffers.
*/
case ACPI_TYPE_BUFFER:
if (obj->buffer.length == 0x104) {
// Skip the first 4 bytes.
obj->buffer.pointer += 4;
len = 0x100;
} else {
dev_err(huawei->dev, "Bad buffer length, got %d\n", obj->buffer.length);
err = -EIO;
goto fail_cmd;
}
break;
/* HWMI returns a package with 2 buffer elements, one of 4 bytes and the
* other is 256 bytes.
*/
case ACPI_TYPE_PACKAGE:
if (obj->package.count != 2) {
dev_err(huawei->dev, "Bad package count, got %d\n", obj->package.count);
err = -EIO;
goto fail_cmd;
}
obj = &obj->package.elements[1];
if (obj->type != ACPI_TYPE_BUFFER) {
dev_err(huawei->dev, "Bad package element type, got %d\n", obj->type);
err = -EIO;
goto fail_cmd;
}
len = obj->buffer.length;
break;
/* Shouldn't get here! */
default:
dev_err(huawei->dev, "Unexpected obj type, got: %d\n", obj->type);
err = -EIO;
goto fail_cmd;
}
if (!*obj->buffer.pointer)
break;
}
err = (*obj->buffer.pointer) ? -ENODEV : 0;
if (buf) {
len = min(buflen, len);
memcpy(buf, obj->buffer.pointer, len);
}
fail_cmd:
kfree(out.pointer);
return err;
}
/* LEDs */
static int huawei_wmi_micmute_led_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
/* This is a workaround until the "legacy" interface is implemented. */
if (quirks && quirks->ec_micmute) {
char *acpi_method;
acpi_handle handle;
acpi_status status;
union acpi_object args[3];
struct acpi_object_list arg_list = {
.pointer = args,
.count = ARRAY_SIZE(args),
};
handle = ec_get_handle();
if (!handle)
return -ENODEV;
args[0].type = args[1].type = args[2].type = ACPI_TYPE_INTEGER;
args[1].integer.value = 0x04;
if (acpi_has_method(handle, "SPIN")) {
acpi_method = "SPIN";
args[0].integer.value = 0;
args[2].integer.value = brightness ? 1 : 0;
} else if (acpi_has_method(handle, "WPIN")) {
acpi_method = "WPIN";
args[0].integer.value = 1;
args[2].integer.value = brightness ? 0 : 1;
} else {
return -ENODEV;
}
status = acpi_evaluate_object(handle, acpi_method, &arg_list, NULL);
if (ACPI_FAILURE(status))
return -ENODEV;
return 0;
} else {
union hwmi_arg arg;
arg.cmd = MICMUTE_LED_SET;
arg.args[2] = brightness;
return huawei_wmi_cmd(arg.cmd, NULL, 0);
}
}
static void huawei_wmi_leds_setup(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
huawei->cdev.name = "platform::micmute";
huawei->cdev.max_brightness = 1;
huawei->cdev.brightness_set_blocking = &huawei_wmi_micmute_led_set;
huawei->cdev.default_trigger = "audio-micmute";
huawei->cdev.brightness = ledtrig_audio_get(LED_AUDIO_MICMUTE);
huawei->cdev.dev = dev;
huawei->cdev.flags = LED_CORE_SUSPENDRESUME;
devm_led_classdev_register(dev, &huawei->cdev);
}
/* Battery protection */
static int huawei_wmi_battery_get(int *start, int *end)
{
u8 ret[0x100];
int err, i;
err = huawei_wmi_cmd(BATTERY_THRESH_GET, ret, 0x100);
if (err)
return err;
/* Find the last two non-zero values. Return status is ignored. */
i = 0xff;
do {
if (start)
*start = ret[i-1];
if (end)
*end = ret[i];
} while (i > 2 && !ret[i--]);
return 0;
}
static int huawei_wmi_battery_set(int start, int end)
{
union hwmi_arg arg;
int err;
if (start < 0 || end < 0 || start > 100 || end > 100)
return -EINVAL;
arg.cmd = BATTERY_THRESH_SET;
arg.args[2] = start;
arg.args[3] = end;
/* This is an edge case were some models turn battery protection
* off without changing their thresholds values. We clear the
* values before turning off protection. Sometimes we need a sleep delay to
* make sure these values make their way to EC memory.
*/
if (quirks && quirks->battery_reset && start == 0 && end == 100) {
err = huawei_wmi_battery_set(0, 0);
if (err)
return err;
msleep(1000);
}
err = huawei_wmi_cmd(arg.cmd, NULL, 0);
return err;
}
static ssize_t charge_control_start_threshold_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int err, start;
err = huawei_wmi_battery_get(&start, NULL);
if (err)
return err;
return sprintf(buf, "%d\n", start);
}
static ssize_t charge_control_end_threshold_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int err, end;
err = huawei_wmi_battery_get(NULL, &end);
if (err)
return err;
return sprintf(buf, "%d\n", end);
}
static ssize_t charge_control_thresholds_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int err, start, end;
err = huawei_wmi_battery_get(&start, &end);
if (err)
return err;
return sprintf(buf, "%d %d\n", start, end);
}
static ssize_t charge_control_start_threshold_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
int err, start, end;
err = huawei_wmi_battery_get(NULL, &end);
if (err)
return err;
if (sscanf(buf, "%d", &start) != 1)
return -EINVAL;
err = huawei_wmi_battery_set(start, end);
if (err)
return err;
return size;
}
static ssize_t charge_control_end_threshold_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
int err, start, end;
err = huawei_wmi_battery_get(&start, NULL);
if (err)
return err;
if (sscanf(buf, "%d", &end) != 1)
return -EINVAL;
err = huawei_wmi_battery_set(start, end);
if (err)
return err;
return size;
}
static ssize_t charge_control_thresholds_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
int err, start, end;
if (sscanf(buf, "%d %d", &start, &end) != 2)
return -EINVAL;
err = huawei_wmi_battery_set(start, end);
if (err)
return err;
return size;
}
static DEVICE_ATTR_RW(charge_control_start_threshold);
static DEVICE_ATTR_RW(charge_control_end_threshold);
static DEVICE_ATTR_RW(charge_control_thresholds);
static int huawei_wmi_battery_add(struct power_supply *battery)
{
int err = 0;
err = device_create_file(&battery->dev, &dev_attr_charge_control_start_threshold);
if (err)
return err;
err = device_create_file(&battery->dev, &dev_attr_charge_control_end_threshold);
if (err)
device_remove_file(&battery->dev, &dev_attr_charge_control_start_threshold);
return err;
}
static int huawei_wmi_battery_remove(struct power_supply *battery)
{
device_remove_file(&battery->dev, &dev_attr_charge_control_start_threshold);
device_remove_file(&battery->dev, &dev_attr_charge_control_end_threshold);
return 0;
}
static struct acpi_battery_hook huawei_wmi_battery_hook = {
.add_battery = huawei_wmi_battery_add,
.remove_battery = huawei_wmi_battery_remove,
.name = "Huawei Battery Extension"
};
static void huawei_wmi_battery_setup(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
huawei->battery_available = true;
if (huawei_wmi_battery_get(NULL, NULL)) {
huawei->battery_available = false;
return;
}
battery_hook_register(&huawei_wmi_battery_hook);
device_create_file(dev, &dev_attr_charge_control_thresholds);
}
static void huawei_wmi_battery_exit(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
if (huawei->battery_available) {
battery_hook_unregister(&huawei_wmi_battery_hook);
device_remove_file(dev, &dev_attr_charge_control_thresholds);
}
}
/* Fn lock */
static int huawei_wmi_fn_lock_get(int *on)
{
u8 ret[0x100] = { 0 };
int err, i;
err = huawei_wmi_cmd(FN_LOCK_GET, ret, 0x100);
if (err)
return err;
/* Find the first non-zero value. Return status is ignored. */
i = 1;
do {
if (on)
*on = ret[i] - 1; // -1 undefined, 0 off, 1 on.
} while (i < 0xff && !ret[i++]);
return 0;
}
static int huawei_wmi_fn_lock_set(int on)
{
union hwmi_arg arg;
arg.cmd = FN_LOCK_SET;
arg.args[2] = on + 1; // 0 undefined, 1 off, 2 on.
return huawei_wmi_cmd(arg.cmd, NULL, 0);
}
static ssize_t fn_lock_state_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int err, on;
err = huawei_wmi_fn_lock_get(&on);
if (err)
return err;
return sprintf(buf, "%d\n", on);
}
static ssize_t fn_lock_state_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
int on, err;
if (kstrtoint(buf, 10, &on) ||
on < 0 || on > 1)
return -EINVAL;
err = huawei_wmi_fn_lock_set(on);
if (err)
return err;
return size;
}
static DEVICE_ATTR_RW(fn_lock_state);
static void huawei_wmi_fn_lock_setup(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
huawei->fn_lock_available = true;
if (huawei_wmi_fn_lock_get(NULL)) {
huawei->fn_lock_available = false;
return;
}
device_create_file(dev, &dev_attr_fn_lock_state);
}
static void huawei_wmi_fn_lock_exit(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
if (huawei->fn_lock_available)
device_remove_file(dev, &dev_attr_fn_lock_state);
}
/* debugfs */
static void huawei_wmi_debugfs_call_dump(struct seq_file *m, void *data,
union acpi_object *obj)
{
struct huawei_wmi *huawei = m->private;
int i;
switch (obj->type) {
case ACPI_TYPE_INTEGER:
seq_printf(m, "0x%llx", obj->integer.value);
break;
case ACPI_TYPE_STRING:
seq_printf(m, "\"%.*s\"", obj->string.length, obj->string.pointer);
break;
case ACPI_TYPE_BUFFER:
seq_puts(m, "{");
for (i = 0; i < obj->buffer.length; i++) {
seq_printf(m, "0x%02x", obj->buffer.pointer[i]);
if (i < obj->buffer.length - 1)
seq_puts(m, ",");
}
seq_puts(m, "}");
break;
case ACPI_TYPE_PACKAGE:
seq_puts(m, "[");
for (i = 0; i < obj->package.count; i++) {
huawei_wmi_debugfs_call_dump(m, huawei, &obj->package.elements[i]);
if (i < obj->package.count - 1)
seq_puts(m, ",");
}
seq_puts(m, "]");
break;
default:
dev_err(huawei->dev, "Unexpected obj type, got %d\n", obj->type);
return;
}
}
static int huawei_wmi_debugfs_call_show(struct seq_file *m, void *data)
{
struct huawei_wmi *huawei = m->private;
struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
struct acpi_buffer in;
union acpi_object *obj;
int err;
in.length = sizeof(u64);
in.pointer = &huawei->debug.arg;
err = huawei_wmi_call(huawei, &in, &out);
if (err)
return err;
obj = out.pointer;
if (!obj) {
err = -EIO;
goto fail_debugfs_call;
}
huawei_wmi_debugfs_call_dump(m, huawei, obj);
fail_debugfs_call:
kfree(out.pointer);
return err;
}
DEFINE_SHOW_ATTRIBUTE(huawei_wmi_debugfs_call);
static void huawei_wmi_debugfs_setup(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
huawei->debug.root = debugfs_create_dir("huawei-wmi", NULL);
debugfs_create_x64("arg", 0644, huawei->debug.root,
&huawei->debug.arg);
debugfs_create_file("call", 0400,
huawei->debug.root, huawei, &huawei_wmi_debugfs_call_fops);
}
static void huawei_wmi_debugfs_exit(struct device *dev)
{
struct huawei_wmi *huawei = dev_get_drvdata(dev);
debugfs_remove_recursive(huawei->debug.root);
}
/* Input */
static void huawei_wmi_process_key(struct input_dev *idev, int code)
{
const struct key_entry *key;
/*
* WMI0 uses code 0x80 to indicate a hotkey event.
* The actual key is fetched from the method WQ00
* using WMI0_EXPENSIVE_GUID.
*/
if (code == 0x80) {
struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
status = wmi_query_block(WMI0_EXPENSIVE_GUID, 0, &response);
if (ACPI_FAILURE(status))
return;
obj = (union acpi_object *)response.pointer;
if (obj && obj->type == ACPI_TYPE_INTEGER)
code = obj->integer.value;
kfree(response.pointer);
}
key = sparse_keymap_entry_from_scancode(idev, code);
if (!key) {
dev_info(&idev->dev, "Unknown key pressed, code: 0x%04x\n", code);
return;
}
if (quirks && !quirks->report_brightness &&
(key->sw.code == KEY_BRIGHTNESSDOWN ||
key->sw.code == KEY_BRIGHTNESSUP))
return;
sparse_keymap_report_entry(idev, key, 1, true);
}
static void huawei_wmi_input_notify(u32 value, void *context)
{
struct input_dev *idev = (struct input_dev *)context;
struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
acpi_status status;
status = wmi_get_event_data(value, &response);
if (ACPI_FAILURE(status)) {
dev_err(&idev->dev, "Unable to get event data\n");
return;
}
obj = (union acpi_object *)response.pointer;
if (obj && obj->type == ACPI_TYPE_INTEGER)
huawei_wmi_process_key(idev, obj->integer.value);
else
dev_err(&idev->dev, "Bad response type\n");
kfree(response.pointer);
}
static int huawei_wmi_input_setup(struct device *dev,
const char *guid,
struct input_dev **idev)
{
acpi_status status;
int err;
*idev = devm_input_allocate_device(dev);
if (!*idev)
return -ENOMEM;
(*idev)->name = "Huawei WMI hotkeys";
(*idev)->phys = "wmi/input0";
(*idev)->id.bustype = BUS_HOST;
(*idev)->dev.parent = dev;
err = sparse_keymap_setup(*idev, huawei_wmi_keymap, NULL);
if (err)
return err;
err = input_register_device(*idev);
if (err)
return err;
status = wmi_install_notify_handler(guid, huawei_wmi_input_notify, *idev);
if (ACPI_FAILURE(status))
return -EIO;
return 0;
}
static void huawei_wmi_input_exit(struct device *dev, const char *guid)
{
wmi_remove_notify_handler(guid);
}
/* Huawei driver */
static const struct wmi_device_id huawei_wmi_events_id_table[] = {
{ .guid_string = WMI0_EVENT_GUID },
{ .guid_string = HWMI_EVENT_GUID },
{ }
};
static int huawei_wmi_probe(struct platform_device *pdev)
{
const struct wmi_device_id *guid = huawei_wmi_events_id_table;
int err;
platform_set_drvdata(pdev, huawei_wmi);
huawei_wmi->dev = &pdev->dev;
while (*guid->guid_string) {
struct input_dev *idev = *huawei_wmi->idev;
if (wmi_has_guid(guid->guid_string)) {
err = huawei_wmi_input_setup(&pdev->dev, guid->guid_string, &idev);
if (err) {
dev_err(&pdev->dev, "Failed to setup input on %s\n", guid->guid_string);
return err;
}
}
idev++;
guid++;
}
if (wmi_has_guid(HWMI_METHOD_GUID)) {
mutex_init(&huawei_wmi->wmi_lock);
huawei_wmi_leds_setup(&pdev->dev);
huawei_wmi_fn_lock_setup(&pdev->dev);
huawei_wmi_battery_setup(&pdev->dev);
huawei_wmi_debugfs_setup(&pdev->dev);
}
return 0;
}
static int huawei_wmi_remove(struct platform_device *pdev)
{
const struct wmi_device_id *guid = huawei_wmi_events_id_table;
while (*guid->guid_string) {
if (wmi_has_guid(guid->guid_string))
huawei_wmi_input_exit(&pdev->dev, guid->guid_string);
guid++;
}
if (wmi_has_guid(HWMI_METHOD_GUID)) {
huawei_wmi_debugfs_exit(&pdev->dev);
huawei_wmi_battery_exit(&pdev->dev);
huawei_wmi_fn_lock_exit(&pdev->dev);
}
return 0;
}
static struct platform_driver huawei_wmi_driver = {
.driver = {
.name = "huawei-wmi",
},
.probe = huawei_wmi_probe,
.remove = huawei_wmi_remove,
};
static __init int huawei_wmi_init(void)
{
struct platform_device *pdev;
int err;
huawei_wmi = kzalloc(sizeof(struct huawei_wmi), GFP_KERNEL);
if (!huawei_wmi)
return -ENOMEM;
quirks = &quirk_unknown;
dmi_check_system(huawei_quirks);
if (battery_reset != -1)
quirks->battery_reset = battery_reset;
if (report_brightness != -1)
quirks->report_brightness = report_brightness;
err = platform_driver_register(&huawei_wmi_driver);
if (err)
goto pdrv_err;
pdev = platform_device_register_simple("huawei-wmi", -1, NULL, 0);
if (IS_ERR(pdev)) {
err = PTR_ERR(pdev);
goto pdev_err;
}
return 0;
pdev_err:
platform_driver_unregister(&huawei_wmi_driver);
pdrv_err:
kfree(huawei_wmi);
return err;
}
static __exit void huawei_wmi_exit(void)
{
struct platform_device *pdev = to_platform_device(huawei_wmi->dev);
platform_device_unregister(pdev);
platform_driver_unregister(&huawei_wmi_driver);
kfree(huawei_wmi);
}
module_init(huawei_wmi_init);
module_exit(huawei_wmi_exit);
MODULE_ALIAS("wmi:"HWMI_METHOD_GUID);
MODULE_DEVICE_TABLE(wmi, huawei_wmi_events_id_table);
MODULE_AUTHOR("Ayman Bagabas <ayman.bagabas@gmail.com>");
MODULE_DESCRIPTION("Huawei WMI laptop extras driver");
MODULE_LICENSE("GPL v2");