// SPDX-License-Identifier: GPL-2.0-only
/*
 * huawei-gaokun-ec - An EC driver for HUAWEI Matebook E Go
 *
 * Copyright (C) 2024-2025 Pengyu Luo <mitltlatltl@gmail.com>
 */

#include <linux/auxiliary_bus.h>
#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/notifier.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_data/huawei-gaokun-ec.h>

#define EC_EVENT                0x06

/* Also can be found in ACPI specification 12.3 */
#define EC_READ                 0x80
#define EC_WRITE                0x81
#define EC_BURST                0x82
#define EC_QUERY                0x84

#define EC_FN_LOCK_ON           0x5A
#define EC_FN_LOCK_OFF          0x55
#define EC_FN_LOCK_READ         0x6B
#define EC_FN_LOCK_WRITE        0x6C

#define EC_EVENT_LID            0x81

#define EC_LID_STATE            0x80
#define EC_LID_OPEN             BIT(1)

#define EC_TEMP_REG             0x61

#define EC_STANDBY_REG          0xB2
#define EC_STANDBY_ENTER        0xDB
#define EC_STANDBY_EXIT         0xEB

enum gaokun_ec_smart_charge_cmd {
        SMART_CHARGE_DATA_WRITE = 0xE3,
        SMART_CHARGE_DATA_READ,
        SMART_CHARGE_ENABLE_WRITE,
        SMART_CHARGE_ENABLE_READ,
};

enum gaokun_ec_ucsi_cmd {
        UCSI_REG_WRITE = 0xD2,
        UCSI_REG_READ,
        UCSI_DATA_WRITE,
        UCSI_DATA_READ,
};

#define UCSI_REG_SIZE           7

/*
 * For tx, command sequences are arranged as
 * {master_cmd, slave_cmd, data_len, data_seq}
 */
#define REQ_HDR_SIZE            3
#define INPUT_SIZE_OFFSET       2
#define REQ_LEN(req) (REQ_HDR_SIZE + (req)[INPUT_SIZE_OFFSET])

/*
 * For rx, data sequences are arranged as
 * {status, data_len(unreliable), data_seq}
 */
#define RESP_HDR_SIZE           2

#define MKREQ(REG0, REG1, SIZE, ...)                    \
{                                                       \
        REG0, REG1, SIZE,                               \
        /* ## will remove comma when SIZE is 0 */       \
        ## __VA_ARGS__,                                 \
        /* make sure len(pkt[3:]) >= SIZE */            \
        [3 + (SIZE)] = 0,                               \
}

#define MKRESP(SIZE)                            \
{                                               \
        [RESP_HDR_SIZE + (SIZE) - 1] = 0,       \
}

/* Possible size 1, 4, 20, 24. Most of the time, the size is 1. */
static inline void refill_req(u8 *dest, const u8 *src, size_t size)
{
        memcpy(dest + REQ_HDR_SIZE, src, size);
}

static inline void refill_req_byte(u8 *dest, const u8 *src)
{
        dest[REQ_HDR_SIZE] = *src;
}

/* Possible size 1, 2, 4, 7, 20. Most of the time, the size is 1. */
static inline void extr_resp(u8 *dest, const u8 *src, size_t size)
{
        memcpy(dest, src + RESP_HDR_SIZE, size);
}

static inline void extr_resp_byte(u8 *dest, const u8 *src)
{
        *dest = src[RESP_HDR_SIZE];
}

static inline void *extr_resp_shallow(const u8 *src)
{
        return (void *)(src + RESP_HDR_SIZE);
}

struct gaokun_ec {
        struct i2c_client *client;
        struct mutex lock; /* EC transaction lock */
        struct blocking_notifier_head notifier_list;
        struct device *hwmon_dev;
        struct input_dev *idev;
        bool suspended;
};

static int gaokun_ec_request(struct gaokun_ec *ec, const u8 *req,
                             size_t resp_len, u8 *resp)
{
        struct i2c_client *client = ec->client;
        struct i2c_msg msgs[] = {
                {
                        .addr = client->addr,
                        .flags = client->flags,
                        .len = REQ_LEN(req),
                        .buf = (void *)req,
                }, {
                        .addr = client->addr,
                        .flags = client->flags | I2C_M_RD,
                        .len = resp_len,
                        .buf = resp,
                },
        };
        int ret;

        guard(mutex)(&ec->lock);
        ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
        if (ret != ARRAY_SIZE(msgs)) {
                dev_err(&client->dev, "I2C transfer error %d\n", ret);
                goto out_after_break;
        }

        ret = *resp;
        if (ret)
                dev_err(&client->dev, "EC transaction error %d\n", ret);

out_after_break:
        usleep_range(2000, 2500); /* have a break, ACPI did this */

        return ret;
}

/* -------------------------------------------------------------------------- */
/* Common API */

/**
 * gaokun_ec_read - Read from EC
 * @ec: The gaokun_ec structure
 * @req: The sequence to request
 * @resp_len: The size to read
 * @resp: The buffer to store response sequence
 *
 * This function is used to read data after writing a magic sequence to EC.
 * All EC operations depend on this function.
 *
 * Huawei uses magic sequences everywhere to complete various functions, all
 * these sequences are passed to ECCD(a ACPI method which is quiet similar
 * to gaokun_ec_request), there is no good abstraction to generalize these
 * sequences, so just wrap it for now. Almost all magic sequences are kept
 * in this file.
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_read(struct gaokun_ec *ec, const u8 *req,
                   size_t resp_len, u8 *resp)
{
        return gaokun_ec_request(ec, req, resp_len, resp);
}
EXPORT_SYMBOL_GPL(gaokun_ec_read);

/**
 * gaokun_ec_write - Write to EC
 * @ec: The gaokun_ec structure
 * @req: The sequence to request
 *
 * This function has no big difference from gaokun_ec_read. When caller care
 * only write status and no actual data are returned, then use it.
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_write(struct gaokun_ec *ec, const u8 *req)
{
        u8 ec_resp[] = MKRESP(0);

        return gaokun_ec_request(ec, req, sizeof(ec_resp), ec_resp);
}
EXPORT_SYMBOL_GPL(gaokun_ec_write);

int gaokun_ec_read_byte(struct gaokun_ec *ec, const u8 *req, u8 *byte)
{
        int ret;
        u8 ec_resp[] = MKRESP(sizeof(*byte));

        ret = gaokun_ec_read(ec, req, sizeof(ec_resp), ec_resp);
        extr_resp_byte(byte, ec_resp);

        return ret;
}
EXPORT_SYMBOL_GPL(gaokun_ec_read_byte);

/**
 * gaokun_ec_register_notify - Register a notifier callback for EC events.
 * @ec: The gaokun_ec structure
 * @nb: Notifier block pointer to register
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_register_notify(struct gaokun_ec *ec, struct notifier_block *nb)
{
        return blocking_notifier_chain_register(&ec->notifier_list, nb);
}
EXPORT_SYMBOL_GPL(gaokun_ec_register_notify);

/**
 * gaokun_ec_unregister_notify - Unregister notifier callback for EC events.
 * @ec: The gaokun_ec structure
 * @nb: Notifier block pointer to unregister
 *
 * Unregister a notifier callback that was previously registered with
 * gaokun_ec_register_notify().
 */
void gaokun_ec_unregister_notify(struct gaokun_ec *ec, struct notifier_block *nb)
{
        blocking_notifier_chain_unregister(&ec->notifier_list, nb);
}
EXPORT_SYMBOL_GPL(gaokun_ec_unregister_notify);

/* -------------------------------------------------------------------------- */
/* API for PSY */

/**
 * gaokun_ec_psy_multi_read - Read contiguous registers
 * @ec: The gaokun_ec structure
 * @reg: The start register
 * @resp_len: The number of registers to be read
 * @resp: The buffer to store response sequence
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_psy_multi_read(struct gaokun_ec *ec, u8 reg,
                             size_t resp_len, u8 *resp)
{
        u8 ec_req[] = MKREQ(0x02, EC_READ, 1, 0);
        u8 ec_resp[] = MKRESP(1);
        int i, ret;

        for (i = 0; i < resp_len; ++i, reg++) {
                refill_req_byte(ec_req, &reg);
                ret = gaokun_ec_read(ec, ec_req, sizeof(ec_resp), ec_resp);
                if (ret)
                        return ret;
                extr_resp_byte(&resp[i], ec_resp);
        }

        return 0;
}
EXPORT_SYMBOL_GPL(gaokun_ec_psy_multi_read);

/* Smart charge */

/**
 * gaokun_ec_psy_get_smart_charge - Get smart charge data from EC
 * @ec: The gaokun_ec structure
 * @resp: The buffer to store response sequence (mode, delay, start, end)
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_psy_get_smart_charge(struct gaokun_ec *ec,
                                   u8 resp[GAOKUN_SMART_CHARGE_DATA_SIZE])
{
        /* GBCM */
        u8 ec_req[] = MKREQ(0x02, SMART_CHARGE_DATA_READ, 0);
        u8 ec_resp[] = MKRESP(GAOKUN_SMART_CHARGE_DATA_SIZE);
        int ret;

        ret = gaokun_ec_read(ec, ec_req, sizeof(ec_resp), ec_resp);
        if (ret)
                return ret;

        extr_resp(resp, ec_resp, GAOKUN_SMART_CHARGE_DATA_SIZE);

        return 0;
}
EXPORT_SYMBOL_GPL(gaokun_ec_psy_get_smart_charge);

static inline bool validate_battery_threshold_range(u8 start, u8 end)
{
        return end != 0 && start <= end && end <= 100;
}

/**
 * gaokun_ec_psy_set_smart_charge - Set smart charge data
 * @ec: The gaokun_ec structure
 * @req: The sequence to request (mode, delay, start, end)
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_psy_set_smart_charge(struct gaokun_ec *ec,
                                   const u8 req[GAOKUN_SMART_CHARGE_DATA_SIZE])
{
        /* SBCM */
        u8 ec_req[] = MKREQ(0x02, SMART_CHARGE_DATA_WRITE,
                            GAOKUN_SMART_CHARGE_DATA_SIZE);

        if (!validate_battery_threshold_range(req[2], req[3]))
                return -EINVAL;

        refill_req(ec_req, req, GAOKUN_SMART_CHARGE_DATA_SIZE);

        return gaokun_ec_write(ec, ec_req);
}
EXPORT_SYMBOL_GPL(gaokun_ec_psy_set_smart_charge);

/* Smart charge enable */

/**
 * gaokun_ec_psy_get_smart_charge_enable - Get smart charge state
 * @ec: The gaokun_ec structure
 * @on: The state
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_psy_get_smart_charge_enable(struct gaokun_ec *ec, bool *on)
{
        /* GBAC */
        u8 ec_req[] = MKREQ(0x02, SMART_CHARGE_ENABLE_READ, 0);
        u8 state;
        int ret;

        ret = gaokun_ec_read_byte(ec, ec_req, &state);
        if (ret)
                return ret;

        *on = !!state;

        return 0;
}
EXPORT_SYMBOL_GPL(gaokun_ec_psy_get_smart_charge_enable);

/**
 * gaokun_ec_psy_set_smart_charge_enable - Set smart charge state
 * @ec: The gaokun_ec structure
 * @on: The state
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_psy_set_smart_charge_enable(struct gaokun_ec *ec, bool on)
{
        /* SBAC */
        u8 ec_req[] = MKREQ(0x02, SMART_CHARGE_ENABLE_WRITE, 1, on);

        return gaokun_ec_write(ec, ec_req);
}
EXPORT_SYMBOL_GPL(gaokun_ec_psy_set_smart_charge_enable);

/* -------------------------------------------------------------------------- */
/* API for UCSI */

/**
 * gaokun_ec_ucsi_read - Read UCSI data from EC
 * @ec: The gaokun_ec structure
 * @resp: The buffer to store response sequence
 *
 * Read CCI and MSGI (used by UCSI subdriver).
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_ucsi_read(struct gaokun_ec *ec,
                        u8 resp[GAOKUN_UCSI_READ_SIZE])
{
        u8 ec_req[] = MKREQ(0x03, UCSI_DATA_READ, 0);
        u8 ec_resp[] = MKRESP(GAOKUN_UCSI_READ_SIZE);
        int ret;

        ret = gaokun_ec_read(ec, ec_req, sizeof(ec_resp), ec_resp);
        if (ret)
                return ret;

        extr_resp(resp, ec_resp, GAOKUN_UCSI_READ_SIZE);
        return 0;
}
EXPORT_SYMBOL_GPL(gaokun_ec_ucsi_read);

/**
 * gaokun_ec_ucsi_write - Write UCSI data to EC
 * @ec: The gaokun_ec structure
 * @req: The sequence to request
 *
 * Write CTRL and MSGO (used by UCSI subdriver).
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_ucsi_write(struct gaokun_ec *ec,
                         const u8 req[GAOKUN_UCSI_WRITE_SIZE])
{
        u8 ec_req[] = MKREQ(0x03, UCSI_DATA_WRITE, GAOKUN_UCSI_WRITE_SIZE);

        refill_req(ec_req, req, GAOKUN_UCSI_WRITE_SIZE);

        return gaokun_ec_write(ec, ec_req);
}
EXPORT_SYMBOL_GPL(gaokun_ec_ucsi_write);

/**
 * gaokun_ec_ucsi_get_reg - Get UCSI register from EC
 * @ec: The gaokun_ec structure
 * @ureg: The gaokun ucsi register
 *
 * Get UCSI register data (used by UCSI subdriver).
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_ucsi_get_reg(struct gaokun_ec *ec, struct gaokun_ucsi_reg *ureg)
{
        u8 ec_req[] = MKREQ(0x03, UCSI_REG_READ, 0);
        u8 ec_resp[] = MKRESP(UCSI_REG_SIZE);
        int ret;

        ret = gaokun_ec_read(ec, ec_req, sizeof(ec_resp), ec_resp);
        if (ret)
                return ret;

        extr_resp((u8 *)ureg, ec_resp, UCSI_REG_SIZE);

        return 0;
}
EXPORT_SYMBOL_GPL(gaokun_ec_ucsi_get_reg);

/**
 * gaokun_ec_ucsi_pan_ack - Ack pin assignment notifications from EC
 * @ec: The gaokun_ec structure
 * @port_id: The port id receiving and handling the notifications
 *
 * Ack pin assignment notifications (used by UCSI subdriver).
 *
 * Return: 0 on success or negative error code.
 */
int gaokun_ec_ucsi_pan_ack(struct gaokun_ec *ec, int port_id)
{
        u8 ec_req[] = MKREQ(0x03, UCSI_REG_WRITE, 1);
        u8 data = 1 << port_id;

        if (port_id == GAOKUN_UCSI_NO_PORT_UPDATE)
                data = 0;

        refill_req_byte(ec_req, &data);

        return gaokun_ec_write(ec, ec_req);
}
EXPORT_SYMBOL_GPL(gaokun_ec_ucsi_pan_ack);

/* -------------------------------------------------------------------------- */
/* EC Sysfs */

/* Fn lock */
static int gaokun_ec_get_fn_lock(struct gaokun_ec *ec, bool *on)
{
        /* GFRS */
        u8 ec_req[] = MKREQ(0x02, EC_FN_LOCK_READ, 0);
        int ret;
        u8 state;

        ret = gaokun_ec_read_byte(ec, ec_req, &state);
        if (ret)
                return ret;

        if (state == EC_FN_LOCK_ON)
                *on = true;
        else if (state == EC_FN_LOCK_OFF)
                *on = false;
        else
                return -EIO;

        return 0;
}

static int gaokun_ec_set_fn_lock(struct gaokun_ec *ec, bool on)
{
        /* SFRS */
        u8 ec_req[] = MKREQ(0x02, EC_FN_LOCK_WRITE, 1,
                            on ? EC_FN_LOCK_ON : EC_FN_LOCK_OFF);

        return gaokun_ec_write(ec, ec_req);
}

static ssize_t fn_lock_show(struct device *dev,
                            struct device_attribute *attr,
                            char *buf)
{
        struct gaokun_ec *ec = dev_get_drvdata(dev);
        bool on;
        int ret;

        ret = gaokun_ec_get_fn_lock(ec, &on);
        if (ret)
                return ret;

        return sysfs_emit(buf, "%d\n", on);
}

static ssize_t fn_lock_store(struct device *dev,
                             struct device_attribute *attr,
                             const char *buf, size_t size)
{
        struct gaokun_ec *ec = dev_get_drvdata(dev);
        bool on;
        int ret;

        if (kstrtobool(buf, &on))
                return -EINVAL;

        ret = gaokun_ec_set_fn_lock(ec, on);
        if (ret)
                return ret;

        return size;
}

static DEVICE_ATTR_RW(fn_lock);

static struct attribute *gaokun_ec_attrs[] = {
        &dev_attr_fn_lock.attr,
        NULL,
};
ATTRIBUTE_GROUPS(gaokun_ec);

/* -------------------------------------------------------------------------- */
/* Thermal Zone HwMon */

/* Range from 0 to 0x2C, partially valid */
static const u8 temp_reg[] = {
        0x05, 0x07, 0x08, 0x0E, 0x0F, 0x12, 0x15, 0x1E,
        0x1F, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26,
        0x27, 0x28, 0x29, 0x2A
};

static int gaokun_ec_get_temp(struct gaokun_ec *ec, u8 idx, long *temp)
{
        /* GTMP */
        u8 ec_req[] = MKREQ(0x02, EC_TEMP_REG, 1, temp_reg[idx]);
        u8 ec_resp[] = MKRESP(sizeof(__le16));
        __le16 *tmp;
        int ret;

        ret = gaokun_ec_read(ec, ec_req, sizeof(ec_resp), ec_resp);
        if (ret)
                return ret;

        tmp = (__le16 *)extr_resp_shallow(ec_resp);
        *temp = le16_to_cpu(*tmp) * 100; /* convert to HwMon's unit */

        return 0;
}

static umode_t
gaokun_ec_hwmon_is_visible(const void *data, enum hwmon_sensor_types type,
                           u32 attr, int channel)
{
        return type == hwmon_temp ? 0444 : 0;
}

static int
gaokun_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
                     u32 attr, int channel, long *val)
{
        struct gaokun_ec *ec = dev_get_drvdata(dev);

        if (type == hwmon_temp)
                return gaokun_ec_get_temp(ec, channel, val);

        return -EINVAL;
}

static const struct hwmon_ops gaokun_ec_hwmon_ops = {
        .is_visible = gaokun_ec_hwmon_is_visible,
        .read = gaokun_ec_hwmon_read,
};

static u32 gaokun_ec_temp_config[] = {
        [0 ... ARRAY_SIZE(temp_reg) - 1] = HWMON_T_INPUT,
        0
};

static const struct hwmon_channel_info gaokun_ec_temp = {
        .type = hwmon_temp,
        .config = gaokun_ec_temp_config,
};

static const struct hwmon_channel_info * const gaokun_ec_hwmon_info[] = {
        &gaokun_ec_temp,
        NULL
};

static const struct hwmon_chip_info gaokun_ec_hwmon_chip_info = {
        .ops = &gaokun_ec_hwmon_ops,
        .info = gaokun_ec_hwmon_info,
};

/* -------------------------------------------------------------------------- */
/* Modern Standby */

static int gaokun_ec_suspend(struct device *dev)
{
        struct gaokun_ec *ec = dev_get_drvdata(dev);
        u8 ec_req[] = MKREQ(0x02, EC_STANDBY_REG, 1, EC_STANDBY_ENTER);
        int ret;

        if (ec->suspended)
                return 0;

        ret = gaokun_ec_write(ec, ec_req);
        if (ret)
                return ret;

        ec->suspended = true;

        return 0;
}

static int gaokun_ec_resume(struct device *dev)
{
        struct gaokun_ec *ec = dev_get_drvdata(dev);
        u8 ec_req[] = MKREQ(0x02, EC_STANDBY_REG, 1, EC_STANDBY_EXIT);
        int ret;
        int i;

        if (!ec->suspended)
                return 0;

        for (i = 0; i < 3; ++i) {
                ret = gaokun_ec_write(ec, ec_req);
                if (ret == 0)
                        break;

                msleep(100); /* EC need time to resume */
        }

        ec->suspended = false;

        return 0;
}

static void gaokun_aux_release(struct device *dev)
{
        struct auxiliary_device *adev = to_auxiliary_dev(dev);

        of_node_put(dev->of_node);
        kfree(adev);
}

static void gaokun_aux_remove(void *data)
{
        struct auxiliary_device *adev = data;

        auxiliary_device_delete(adev);
        auxiliary_device_uninit(adev);
}

static int gaokun_aux_init(struct device *parent, const char *name,
                           struct gaokun_ec *ec)
{
        struct auxiliary_device *adev;
        int ret;

        adev = kzalloc_obj(*adev);
        if (!adev)
                return -ENOMEM;

        adev->name = name;
        adev->id = 0;
        adev->dev.parent = parent;
        adev->dev.release = gaokun_aux_release;
        adev->dev.platform_data = ec;
        /* Allow aux devices to access parent's DT nodes directly */
        device_set_of_node_from_dev(&adev->dev, parent);

        ret = auxiliary_device_init(adev);
        if (ret) {
                of_node_put(adev->dev.of_node);
                kfree(adev);
                return ret;
        }

        ret = auxiliary_device_add(adev);
        if (ret) {
                auxiliary_device_uninit(adev);
                return ret;
        }

        return devm_add_action_or_reset(parent, gaokun_aux_remove, adev);
}

/* -------------------------------------------------------------------------- */
/* EC */

static irqreturn_t gaokun_ec_irq_handler(int irq, void *data)
{
        struct gaokun_ec *ec = data;
        u8 ec_req[] = MKREQ(EC_EVENT, EC_QUERY, 0);
        u8 status, id;
        int ret;

        ret = gaokun_ec_read_byte(ec, ec_req, &id);
        if (ret)
                return IRQ_HANDLED;

        switch (id) {
        case 0x0: /* No event */
                break;

        case EC_EVENT_LID:
                gaokun_ec_psy_read_byte(ec, EC_LID_STATE, &status);
                status &= EC_LID_OPEN;
                input_report_switch(ec->idev, SW_LID, !status);
                input_sync(ec->idev);
                break;

        default:
                blocking_notifier_call_chain(&ec->notifier_list, id, ec);
        }

        return IRQ_HANDLED;
}

static int gaokun_ec_probe(struct i2c_client *client)
{
        struct device *dev = &client->dev;
        struct gaokun_ec *ec;
        int ret;

        ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL);
        if (!ec)
                return -ENOMEM;

        ret = devm_mutex_init(dev, &ec->lock);
        if (ret)
                return ret;

        ec->client = client;
        i2c_set_clientdata(client, ec);
        BLOCKING_INIT_NOTIFIER_HEAD(&ec->notifier_list);

        /* Lid switch */
        ec->idev = devm_input_allocate_device(dev);
        if (!ec->idev)
                return -ENOMEM;

        ec->idev->name = "LID";
        ec->idev->phys = "gaokun-ec/input0";
        input_set_capability(ec->idev, EV_SW, SW_LID);

        ret = input_register_device(ec->idev);
        if (ret)
                return dev_err_probe(dev, ret, "Failed to register input device\n");

        ret = gaokun_aux_init(dev, GAOKUN_DEV_PSY, ec);
        if (ret)
                return ret;

        ret = gaokun_aux_init(dev, GAOKUN_DEV_UCSI, ec);
        if (ret)
                return ret;

        ret = devm_request_threaded_irq(dev, client->irq, NULL,
                                        gaokun_ec_irq_handler, IRQF_ONESHOT,
                                        dev_name(dev), ec);
        if (ret)
                return dev_err_probe(dev, ret, "Failed to request IRQ\n");

        ec->hwmon_dev = devm_hwmon_device_register_with_info(dev, "gaokun_ec_hwmon",
                                                             ec, &gaokun_ec_hwmon_chip_info, NULL);
        if (IS_ERR(ec->hwmon_dev))
                return dev_err_probe(dev, PTR_ERR(ec->hwmon_dev),
                                     "Failed to register hwmon device\n");

        return 0;
}

static const struct i2c_device_id gaokun_ec_id[] = {
        { "gaokun-ec", },
        { }
};
MODULE_DEVICE_TABLE(i2c, gaokun_ec_id);

static const struct of_device_id gaokun_ec_of_match[] = {
        { .compatible = "huawei,gaokun3-ec", },
        { }
};
MODULE_DEVICE_TABLE(of, gaokun_ec_of_match);

static const struct dev_pm_ops gaokun_ec_pm_ops = {
        NOIRQ_SYSTEM_SLEEP_PM_OPS(gaokun_ec_suspend, gaokun_ec_resume)
};

static struct i2c_driver gaokun_ec_driver = {
        .driver = {
                .name = "gaokun-ec",
                .of_match_table = gaokun_ec_of_match,
                .pm = &gaokun_ec_pm_ops,
                .dev_groups = gaokun_ec_groups,
        },
        .probe = gaokun_ec_probe,
        .id_table = gaokun_ec_id,
};
module_i2c_driver(gaokun_ec_driver);

MODULE_DESCRIPTION("HUAWEI Matebook E Go EC driver");
MODULE_AUTHOR("Pengyu Luo <mitltlatltl@gmail.com>");
MODULE_LICENSE("GPL");