// 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 } },
        { 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)
{
        device_create_file(&battery->dev, &dev_attr_charge_control_start_threshold);
        device_create_file(&battery->dev, &dev_attr_charge_control_end_threshold);

        return 0;
}

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)
{
        *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;

        return sparse_keymap_setup(*idev, huawei_wmi_keymap, NULL) ||
                input_register_device(*idev) ||
                wmi_install_notify_handler(guid, huawei_wmi_input_notify,
                                *idev);
}

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");