w83l786ng.c

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/*
 * w83l786ng.c - Linux kernel driver for hardware monitoring
 * Copyright (c) 2007 Kevin Lo <[email protected]>
 *
 * 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 - version 2.
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301 USA.
 */

/*
 * Supports following chips:
 *
 * Chip     #vin    #fanin  #pwm    #temp   wchipid vendid  i2c ISA
 * w83l786ng    3   2   2   2   0x7b    0x5ca3  yes no
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-vid.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/jiffies.h>

/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2e, 0x2f, I2C_CLIENT_END };

/* Insmod parameters */

static bool reset;
module_param(reset, bool, 0);
MODULE_PARM_DESC(reset, "Set to 1 to reset chip, not recommended");

#define W83L786NG_REG_IN_MIN(nr)    (0x2C + (nr) * 2)
#define W83L786NG_REG_IN_MAX(nr)    (0x2B + (nr) * 2)
#define W83L786NG_REG_IN(nr)        ((nr) + 0x20)

#define W83L786NG_REG_FAN(nr)       ((nr) + 0x28)
#define W83L786NG_REG_FAN_MIN(nr)   ((nr) + 0x3B)

#define W83L786NG_REG_CONFIG        0x40
#define W83L786NG_REG_ALARM1        0x41
#define W83L786NG_REG_ALARM2        0x42
#define W83L786NG_REG_GPIO_EN       0x47
#define W83L786NG_REG_MAN_ID2       0x4C
#define W83L786NG_REG_MAN_ID1       0x4D
#define W83L786NG_REG_CHIP_ID       0x4E

#define W83L786NG_REG_DIODE     0x53
#define W83L786NG_REG_FAN_DIV       0x54
#define W83L786NG_REG_FAN_CFG       0x80

#define W83L786NG_REG_TOLERANCE     0x8D

static const u8 W83L786NG_REG_TEMP[2][3] = {
    { 0x25,     /* TEMP 0 in DataSheet */
      0x35,     /* TEMP 0 Over in DataSheet */
      0x36 },   /* TEMP 0 Hyst in DataSheet */
    { 0x26,     /* TEMP 1 in DataSheet */
      0x37,     /* TEMP 1 Over in DataSheet */
      0x38 }    /* TEMP 1 Hyst in DataSheet */
};

static const u8 W83L786NG_PWM_MODE_SHIFT[] = {6, 7};
static const u8 W83L786NG_PWM_ENABLE_SHIFT[] = {2, 4};

/* FAN Duty Cycle, be used to control */
static const u8 W83L786NG_REG_PWM[] = {0x81, 0x87};


static inline u8
FAN_TO_REG(long rpm, int div)
{
    if (rpm == 0)
        return 255;
    rpm = SENSORS_LIMIT(rpm, 1, 1000000);
    return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
}

#define FAN_FROM_REG(val, div)  ((val) == 0   ? -1 : \
                ((val) == 255 ? 0 : \
                1350000 / ((val) * (div))))

/* for temp */
#define TEMP_TO_REG(val)    (SENSORS_LIMIT(((val) < 0 ? \
                        (val) + 0x100 * 1000 \
                        : (val)) / 1000, 0, 0xff))
#define TEMP_FROM_REG(val)  (((val) & 0x80 ? \
                  (val) - 0x100 : (val)) * 1000)

/*
 * The analog voltage inputs have 8mV LSB. Since the sysfs output is
 * in mV as would be measured on the chip input pin, need to just
 * multiply/divide by 8 to translate from/to register values.
 */
#define IN_TO_REG(val)      (SENSORS_LIMIT((((val) + 4) / 8), 0, 255))
#define IN_FROM_REG(val)    ((val) * 8)

#define DIV_FROM_REG(val)   (1 << (val))

static inline u8
DIV_TO_REG(long val)
{
    int i;
    val = SENSORS_LIMIT(val, 1, 128) >> 1;
    for (i = 0; i < 7; i++) {
        if (val == 0)
            break;
        val >>= 1;
    }
    return (u8)i;
}

struct w83l786ng_data {
    struct device *hwmon_dev;
    struct mutex update_lock;
    char valid;         /* !=0 if following fields are valid */
    unsigned long last_updated; /* In jiffies */
    unsigned long last_nonvolatile; /* In jiffies, last time we update the
                     * nonvolatile registers */

    u8 in[3];
    u8 in_max[3];
    u8 in_min[3];
    u8 fan[2];
    u8 fan_div[2];
    u8 fan_min[2];
    u8 temp_type[2];
    u8 temp[2][3];
    u8 pwm[2];
    u8 pwm_mode[2]; /* 0->DC variable voltage
             * 1->PWM variable duty cycle */

    u8 pwm_enable[2]; /* 1->manual
               * 2->thermal cruise (also called SmartFan I) */
    u8 tolerance[2];
};

static int w83l786ng_probe(struct i2c_client *client,
               const struct i2c_device_id *id);
static int w83l786ng_detect(struct i2c_client *client,
                struct i2c_board_info *info);
static int w83l786ng_remove(struct i2c_client *client);
static void w83l786ng_init_client(struct i2c_client *client);
static struct w83l786ng_data *w83l786ng_update_device(struct device *dev);

static const struct i2c_device_id w83l786ng_id[] = {
    { "w83l786ng", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, w83l786ng_id);

static struct i2c_driver w83l786ng_driver = {
    .class      = I2C_CLASS_HWMON,
    .driver = {
           .name = "w83l786ng",
    },
    .probe      = w83l786ng_probe,
    .remove     = w83l786ng_remove,
    .id_table   = w83l786ng_id,
    .detect     = w83l786ng_detect,
    .address_list   = normal_i2c,
};

static u8
w83l786ng_read_value(struct i2c_client *client, u8 reg)
{
    return i2c_smbus_read_byte_data(client, reg);
}

static int
w83l786ng_write_value(struct i2c_client *client, u8 reg, u8 value)
{
    return i2c_smbus_write_byte_data(client, reg, value);
}

/* following are the sysfs callback functions */
#define show_in_reg(reg) \
static ssize_t \
show_##reg(struct device *dev, struct device_attribute *attr, \
       char *buf) \
{ \
    int nr = to_sensor_dev_attr(attr)->index; \
    struct w83l786ng_data *data = w83l786ng_update_device(dev); \
    return sprintf(buf, "%d\n", IN_FROM_REG(data->reg[nr])); \
}

show_in_reg(in)
show_in_reg(in_min)
show_in_reg(in_max)

#define store_in_reg(REG, reg) \
static ssize_t \
store_in_##reg(struct device *dev, struct device_attribute *attr, \
           const char *buf, size_t count) \
{ \
    int nr = to_sensor_dev_attr(attr)->index; \
    struct i2c_client *client = to_i2c_client(dev); \
    struct w83l786ng_data *data = i2c_get_clientdata(client); \
    unsigned long val; \
    int err = kstrtoul(buf, 10, &val); \
    if (err) \
        return err; \
    mutex_lock(&data->update_lock); \
    data->in_##reg[nr] = IN_TO_REG(val); \
    w83l786ng_write_value(client, W83L786NG_REG_IN_##REG(nr), \
                  data->in_##reg[nr]); \
    mutex_unlock(&data->update_lock); \
    return count; \
}

store_in_reg(MIN, min)
store_in_reg(MAX, max)

static struct sensor_device_attribute sda_in_input[] = {
    SENSOR_ATTR(in0_input, S_IRUGO, show_in, NULL, 0),
    SENSOR_ATTR(in1_input, S_IRUGO, show_in, NULL, 1),
    SENSOR_ATTR(in2_input, S_IRUGO, show_in, NULL, 2),
};

static struct sensor_device_attribute sda_in_min[] = {
    SENSOR_ATTR(in0_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 0),
    SENSOR_ATTR(in1_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 1),
    SENSOR_ATTR(in2_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 2),
};

static struct sensor_device_attribute sda_in_max[] = {
    SENSOR_ATTR(in0_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 0),
    SENSOR_ATTR(in1_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 1),
    SENSOR_ATTR(in2_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 2),
};

#define show_fan_reg(reg) \
static ssize_t show_##reg(struct device *dev, struct device_attribute *attr, \
              char *buf) \
{ \
    int nr = to_sensor_dev_attr(attr)->index; \
    struct w83l786ng_data *data = w83l786ng_update_device(dev); \
    return sprintf(buf, "%d\n", \
        FAN_FROM_REG(data->fan[nr], DIV_FROM_REG(data->fan_div[nr]))); \
}

show_fan_reg(fan);
show_fan_reg(fan_min);

static ssize_t
store_fan_min(struct device *dev, struct device_attribute *attr,
          const char *buf, size_t count)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);
    unsigned long val;
    int err;

    err = kstrtoul(buf, 10, &val);
    if (err)
        return err;

    mutex_lock(&data->update_lock);
    data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
    w83l786ng_write_value(client, W83L786NG_REG_FAN_MIN(nr),
                  data->fan_min[nr]);
    mutex_unlock(&data->update_lock);

    return count;
}

static ssize_t
show_fan_div(struct device *dev, struct device_attribute *attr,
         char *buf)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct w83l786ng_data *data = w83l786ng_update_device(dev);
    return sprintf(buf, "%u\n", DIV_FROM_REG(data->fan_div[nr]));
}

/*
 * Note: we save and restore the fan minimum here, because its value is
 * determined in part by the fan divisor.  This follows the principle of
 * least surprise; the user doesn't expect the fan minimum to change just
 * because the divisor changed.
 */
static ssize_t
store_fan_div(struct device *dev, struct device_attribute *attr,
          const char *buf, size_t count)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);

    unsigned long min;
    u8 tmp_fan_div;
    u8 fan_div_reg;
    u8 keep_mask = 0;
    u8 new_shift = 0;

    unsigned long val;
    int err;

    err = kstrtoul(buf, 10, &val);
    if (err)
        return err;

    /* Save fan_min */
    mutex_lock(&data->update_lock);
    min = FAN_FROM_REG(data->fan_min[nr], DIV_FROM_REG(data->fan_div[nr]));

    data->fan_div[nr] = DIV_TO_REG(val);

    switch (nr) {
    case 0:
        keep_mask = 0xf8;
        new_shift = 0;
        break;
    case 1:
        keep_mask = 0x8f;
        new_shift = 4;
        break;
    }

    fan_div_reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV)
                       & keep_mask;

    tmp_fan_div = (data->fan_div[nr] << new_shift) & ~keep_mask;

    w83l786ng_write_value(client, W83L786NG_REG_FAN_DIV,
                  fan_div_reg | tmp_fan_div);

    /* Restore fan_min */
    data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
    w83l786ng_write_value(client, W83L786NG_REG_FAN_MIN(nr),
                  data->fan_min[nr]);
    mutex_unlock(&data->update_lock);

    return count;
}

static struct sensor_device_attribute sda_fan_input[] = {
    SENSOR_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0),
    SENSOR_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1),
};

static struct sensor_device_attribute sda_fan_min[] = {
    SENSOR_ATTR(fan1_min, S_IWUSR | S_IRUGO, show_fan_min,
            store_fan_min, 0),
    SENSOR_ATTR(fan2_min, S_IWUSR | S_IRUGO, show_fan_min,
            store_fan_min, 1),
};

static struct sensor_device_attribute sda_fan_div[] = {
    SENSOR_ATTR(fan1_div, S_IWUSR | S_IRUGO, show_fan_div,
            store_fan_div, 0),
    SENSOR_ATTR(fan2_div, S_IWUSR | S_IRUGO, show_fan_div,
            store_fan_div, 1),
};


/* read/write the temperature, includes measured value and limits */

static ssize_t
show_temp(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct sensor_device_attribute_2 *sensor_attr =
        to_sensor_dev_attr_2(attr);
    int nr = sensor_attr->nr;
    int index = sensor_attr->index;
    struct w83l786ng_data *data = w83l786ng_update_device(dev);
    return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr][index]));
}

static ssize_t
store_temp(struct device *dev, struct device_attribute *attr,
       const char *buf, size_t count)
{
    struct sensor_device_attribute_2 *sensor_attr =
        to_sensor_dev_attr_2(attr);
    int nr = sensor_attr->nr;
    int index = sensor_attr->index;
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);
    long val;
    int err;

    err = kstrtol(buf, 10, &val);
    if (err)
        return err;

    mutex_lock(&data->update_lock);
    data->temp[nr][index] = TEMP_TO_REG(val);
    w83l786ng_write_value(client, W83L786NG_REG_TEMP[nr][index],
                  data->temp[nr][index]);
    mutex_unlock(&data->update_lock);

    return count;
}

static struct sensor_device_attribute_2 sda_temp_input[] = {
    SENSOR_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0, 0),
    SENSOR_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 1, 0),
};

static struct sensor_device_attribute_2 sda_temp_max[] = {
    SENSOR_ATTR_2(temp1_max, S_IRUGO | S_IWUSR,
              show_temp, store_temp, 0, 1),
    SENSOR_ATTR_2(temp2_max, S_IRUGO | S_IWUSR,
              show_temp, store_temp, 1, 1),
};

static struct sensor_device_attribute_2 sda_temp_max_hyst[] = {
    SENSOR_ATTR_2(temp1_max_hyst, S_IRUGO | S_IWUSR,
              show_temp, store_temp, 0, 2),
    SENSOR_ATTR_2(temp2_max_hyst, S_IRUGO | S_IWUSR,
              show_temp, store_temp, 1, 2),
};

#define show_pwm_reg(reg) \
static ssize_t show_##reg(struct device *dev, struct device_attribute *attr, \
              char *buf) \
{ \
    struct w83l786ng_data *data = w83l786ng_update_device(dev); \
    int nr = to_sensor_dev_attr(attr)->index; \
    return sprintf(buf, "%d\n", data->reg[nr]); \
}

show_pwm_reg(pwm_mode)
show_pwm_reg(pwm_enable)
show_pwm_reg(pwm)

static ssize_t
store_pwm_mode(struct device *dev, struct device_attribute *attr,
           const char *buf, size_t count)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);
    u8 reg;
    unsigned long val;
    int err;

    err = kstrtoul(buf, 10, &val);
    if (err)
        return err;

    if (val > 1)
        return -EINVAL;
    mutex_lock(&data->update_lock);
    data->pwm_mode[nr] = val;
    reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
    reg &= ~(1 << W83L786NG_PWM_MODE_SHIFT[nr]);
    if (!val)
        reg |= 1 << W83L786NG_PWM_MODE_SHIFT[nr];
    w83l786ng_write_value(client, W83L786NG_REG_FAN_CFG, reg);
    mutex_unlock(&data->update_lock);
    return count;
}

static ssize_t
store_pwm(struct device *dev, struct device_attribute *attr,
      const char *buf, size_t count)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);
    unsigned long val;
    int err;

    err = kstrtoul(buf, 10, &val);
    if (err)
        return err;
    val = SENSORS_LIMIT(val, 0, 255);

    mutex_lock(&data->update_lock);
    data->pwm[nr] = val;
    w83l786ng_write_value(client, W83L786NG_REG_PWM[nr], val);
    mutex_unlock(&data->update_lock);
    return count;
}

static ssize_t
store_pwm_enable(struct device *dev, struct device_attribute *attr,
         const char *buf, size_t count)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);
    u8 reg;
    unsigned long val;
    int err;

    err = kstrtoul(buf, 10, &val);
    if (err)
        return err;

    if (!val || val > 2)  /* only modes 1 and 2 are supported */
        return -EINVAL;

    mutex_lock(&data->update_lock);
    reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
    data->pwm_enable[nr] = val;
    reg &= ~(0x02 << W83L786NG_PWM_ENABLE_SHIFT[nr]);
    reg |= (val - 1) << W83L786NG_PWM_ENABLE_SHIFT[nr];
    w83l786ng_write_value(client, W83L786NG_REG_FAN_CFG, reg);
    mutex_unlock(&data->update_lock);
    return count;
}

static struct sensor_device_attribute sda_pwm[] = {
    SENSOR_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, store_pwm, 0),
    SENSOR_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, store_pwm, 1),
};

static struct sensor_device_attribute sda_pwm_mode[] = {
    SENSOR_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, show_pwm_mode,
            store_pwm_mode, 0),
    SENSOR_ATTR(pwm2_mode, S_IWUSR | S_IRUGO, show_pwm_mode,
            store_pwm_mode, 1),
};

static struct sensor_device_attribute sda_pwm_enable[] = {
    SENSOR_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, show_pwm_enable,
            store_pwm_enable, 0),
    SENSOR_ATTR(pwm2_enable, S_IWUSR | S_IRUGO, show_pwm_enable,
            store_pwm_enable, 1),
};

/* For Smart Fan I/Thermal Cruise and Smart Fan II */
static ssize_t
show_tolerance(struct device *dev, struct device_attribute *attr, char *buf)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct w83l786ng_data *data = w83l786ng_update_device(dev);
    return sprintf(buf, "%ld\n", (long)data->tolerance[nr]);
}

static ssize_t
store_tolerance(struct device *dev, struct device_attribute *attr,
        const char *buf, size_t count)
{
    int nr = to_sensor_dev_attr(attr)->index;
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);
    u8 tol_tmp, tol_mask;
    unsigned long val;
    int err;

    err = kstrtoul(buf, 10, &val);
    if (err)
        return err;

    mutex_lock(&data->update_lock);
    tol_mask = w83l786ng_read_value(client,
        W83L786NG_REG_TOLERANCE) & ((nr == 1) ? 0x0f : 0xf0);
    tol_tmp = SENSORS_LIMIT(val, 0, 15);
    tol_tmp &= 0x0f;
    data->tolerance[nr] = tol_tmp;
    if (nr == 1)
        tol_tmp <<= 4;

    w83l786ng_write_value(client, W83L786NG_REG_TOLERANCE,
                  tol_mask | tol_tmp);
    mutex_unlock(&data->update_lock);
    return count;
}

static struct sensor_device_attribute sda_tolerance[] = {
    SENSOR_ATTR(pwm1_tolerance, S_IWUSR | S_IRUGO,
            show_tolerance, store_tolerance, 0),
    SENSOR_ATTR(pwm2_tolerance, S_IWUSR | S_IRUGO,
            show_tolerance, store_tolerance, 1),
};


#define IN_UNIT_ATTRS(X)    \
    &sda_in_input[X].dev_attr.attr,     \
    &sda_in_min[X].dev_attr.attr,       \
    &sda_in_max[X].dev_attr.attr

#define FAN_UNIT_ATTRS(X)   \
    &sda_fan_input[X].dev_attr.attr,    \
    &sda_fan_min[X].dev_attr.attr,      \
    &sda_fan_div[X].dev_attr.attr

#define TEMP_UNIT_ATTRS(X)  \
    &sda_temp_input[X].dev_attr.attr,   \
    &sda_temp_max[X].dev_attr.attr,     \
    &sda_temp_max_hyst[X].dev_attr.attr

#define PWM_UNIT_ATTRS(X)   \
    &sda_pwm[X].dev_attr.attr,      \
    &sda_pwm_mode[X].dev_attr.attr,     \
    &sda_pwm_enable[X].dev_attr.attr

#define TOLERANCE_UNIT_ATTRS(X) \
    &sda_tolerance[X].dev_attr.attr

static struct attribute *w83l786ng_attributes[] = {
    IN_UNIT_ATTRS(0),
    IN_UNIT_ATTRS(1),
    IN_UNIT_ATTRS(2),
    FAN_UNIT_ATTRS(0),
    FAN_UNIT_ATTRS(1),
    TEMP_UNIT_ATTRS(0),
    TEMP_UNIT_ATTRS(1),
    PWM_UNIT_ATTRS(0),
    PWM_UNIT_ATTRS(1),
    TOLERANCE_UNIT_ATTRS(0),
    TOLERANCE_UNIT_ATTRS(1),
    NULL
};

static const struct attribute_group w83l786ng_group = {
    .attrs = w83l786ng_attributes,
};

static int
w83l786ng_detect(struct i2c_client *client, struct i2c_board_info *info)
{
    struct i2c_adapter *adapter = client->adapter;
    u16 man_id;
    u8 chip_id;

    if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
        return -ENODEV;

    /* Detection */
    if ((w83l786ng_read_value(client, W83L786NG_REG_CONFIG) & 0x80)) {
        dev_dbg(&adapter->dev, "W83L786NG detection failed at 0x%02x\n",
            client->addr);
        return -ENODEV;
    }

    /* Identification */
    man_id = (w83l786ng_read_value(client, W83L786NG_REG_MAN_ID1) << 8) +
         w83l786ng_read_value(client, W83L786NG_REG_MAN_ID2);
    chip_id = w83l786ng_read_value(client, W83L786NG_REG_CHIP_ID);

    if (man_id != 0x5CA3 ||     /* Winbond */
        chip_id != 0x80) {      /* W83L786NG */
        dev_dbg(&adapter->dev,
            "Unsupported chip (man_id=0x%04X, chip_id=0x%02X)\n",
            man_id, chip_id);
        return -ENODEV;
    }

    strlcpy(info->type, "w83l786ng", I2C_NAME_SIZE);

    return 0;
}

static int
w83l786ng_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
    struct device *dev = &client->dev;
    struct w83l786ng_data *data;
    int i, err = 0;
    u8 reg_tmp;

    data = devm_kzalloc(&client->dev, sizeof(struct w83l786ng_data),
                GFP_KERNEL);
    if (!data)
        return -ENOMEM;

    i2c_set_clientdata(client, data);
    mutex_init(&data->update_lock);

    /* Initialize the chip */
    w83l786ng_init_client(client);

    /* A few vars need to be filled upon startup */
    for (i = 0; i < 2; i++) {
        data->fan_min[i] = w83l786ng_read_value(client,
            W83L786NG_REG_FAN_MIN(i));
    }

    /* Update the fan divisor */
    reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV);
    data->fan_div[0] = reg_tmp & 0x07;
    data->fan_div[1] = (reg_tmp >> 4) & 0x07;

    /* Register sysfs hooks */
    err = sysfs_create_group(&client->dev.kobj, &w83l786ng_group);
    if (err)
        goto exit_remove;

    data->hwmon_dev = hwmon_device_register(dev);
    if (IS_ERR(data->hwmon_dev)) {
        err = PTR_ERR(data->hwmon_dev);
        goto exit_remove;
    }

    return 0;

    /* Unregister sysfs hooks */

exit_remove:
    sysfs_remove_group(&client->dev.kobj, &w83l786ng_group);
    return err;
}

static int
w83l786ng_remove(struct i2c_client *client)
{
    struct w83l786ng_data *data = i2c_get_clientdata(client);

    hwmon_device_unregister(data->hwmon_dev);
    sysfs_remove_group(&client->dev.kobj, &w83l786ng_group);

    return 0;
}

static void
w83l786ng_init_client(struct i2c_client *client)
{
    u8 tmp;

    if (reset)
        w83l786ng_write_value(client, W83L786NG_REG_CONFIG, 0x80);

    /* Start monitoring */
    tmp = w83l786ng_read_value(client, W83L786NG_REG_CONFIG);
    if (!(tmp & 0x01))
        w83l786ng_write_value(client, W83L786NG_REG_CONFIG, tmp | 0x01);
}

static struct w83l786ng_data *w83l786ng_update_device(struct device *dev)
{
    struct i2c_client *client = to_i2c_client(dev);
    struct w83l786ng_data *data = i2c_get_clientdata(client);
    int i, j;
    u8 reg_tmp, pwmcfg;

    mutex_lock(&data->update_lock);
    if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
        || !data->valid) {
        dev_dbg(&client->dev, "Updating w83l786ng data.\n");

        /* Update the voltages measured value and limits */
        for (i = 0; i < 3; i++) {
            data->in[i] = w83l786ng_read_value(client,
                W83L786NG_REG_IN(i));
            data->in_min[i] = w83l786ng_read_value(client,
                W83L786NG_REG_IN_MIN(i));
            data->in_max[i] = w83l786ng_read_value(client,
                W83L786NG_REG_IN_MAX(i));
        }

        /* Update the fan counts and limits */
        for (i = 0; i < 2; i++) {
            data->fan[i] = w83l786ng_read_value(client,
                W83L786NG_REG_FAN(i));
            data->fan_min[i] = w83l786ng_read_value(client,
                W83L786NG_REG_FAN_MIN(i));
        }

        /* Update the fan divisor */
        reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV);
        data->fan_div[0] = reg_tmp & 0x07;
        data->fan_div[1] = (reg_tmp >> 4) & 0x07;

        pwmcfg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
        for (i = 0; i < 2; i++) {
            data->pwm_mode[i] =
                ((pwmcfg >> W83L786NG_PWM_MODE_SHIFT[i]) & 1)
                ? 0 : 1;
            data->pwm_enable[i] =
                ((pwmcfg >> W83L786NG_PWM_ENABLE_SHIFT[i]) & 2) + 1;
            data->pwm[i] = w83l786ng_read_value(client,
                W83L786NG_REG_PWM[i]);
        }


        /* Update the temperature sensors */
        for (i = 0; i < 2; i++) {
            for (j = 0; j < 3; j++) {
                data->temp[i][j] = w83l786ng_read_value(client,
                    W83L786NG_REG_TEMP[i][j]);
            }
        }

        /* Update Smart Fan I/II tolerance */
        reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_TOLERANCE);
        data->tolerance[0] = reg_tmp & 0x0f;
        data->tolerance[1] = (reg_tmp >> 4) & 0x0f;

        data->last_updated = jiffies;
        data->valid = 1;

    }

    mutex_unlock(&data->update_lock);

    return data;
}

module_i2c_driver(w83l786ng_driver);

MODULE_AUTHOR("Kevin Lo");
MODULE_DESCRIPTION("w83l786ng driver");
MODULE_LICENSE("GPL");