// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * smsc47m192.c - Support for hardware monitoring block of
 *                SMSC LPC47M192 and compatible Super I/O chips
 *
 * Copyright (C) 2006  Hartmut Rick <linux@rick.claranet.de>
 *
 * Derived from lm78.c and other chip drivers.
 */

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

/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END };

/* SMSC47M192 registers */
#define SMSC47M192_REG_IN(nr)           ((nr) < 6 ? (0x20 + (nr)) : \
                                        (0x50 + (nr) - 6))
#define SMSC47M192_REG_IN_MAX(nr)       ((nr) < 6 ? (0x2b + (nr) * 2) : \
                                        (0x54 + (((nr) - 6) * 2)))
#define SMSC47M192_REG_IN_MIN(nr)       ((nr) < 6 ? (0x2c + (nr) * 2) : \
                                        (0x55 + (((nr) - 6) * 2)))
static u8 SMSC47M192_REG_TEMP[3] =      { 0x27, 0x26, 0x52 };
static u8 SMSC47M192_REG_TEMP_MAX[3] =  { 0x39, 0x37, 0x58 };
static u8 SMSC47M192_REG_TEMP_MIN[3] =  { 0x3A, 0x38, 0x59 };
#define SMSC47M192_REG_TEMP_OFFSET(nr)  ((nr) == 2 ? 0x1e : 0x1f)
#define SMSC47M192_REG_ALARM1           0x41
#define SMSC47M192_REG_ALARM2           0x42
#define SMSC47M192_REG_VID              0x47
#define SMSC47M192_REG_VID4             0x49
#define SMSC47M192_REG_CONFIG           0x40
#define SMSC47M192_REG_SFR              0x4f
#define SMSC47M192_REG_COMPANY_ID       0x3e
#define SMSC47M192_REG_VERSION          0x3f

/* generalised scaling with integer rounding */
static inline int SCALE(long val, int mul, int div)
{
        if (val < 0)
                return (val * mul - div / 2) / div;
        else
                return (val * mul + div / 2) / div;
}

/* Conversions */

/* smsc47m192 internally scales voltage measurements */
static const u16 nom_mv[] = { 2500, 2250, 3300, 5000, 12000, 3300, 1500, 1800 };

static inline unsigned int IN_FROM_REG(u8 reg, int n)
{
        return SCALE(reg, nom_mv[n], 192);
}

static inline u8 IN_TO_REG(unsigned long val, int n)
{
        val = clamp_val(val, 0, nom_mv[n] * 255 / 192);
        return SCALE(val, 192, nom_mv[n]);
}

/*
 * TEMP: 0.001 degC units (-128C to +127C)
 * REG: 1C/bit, two's complement
 */
static inline s8 TEMP_TO_REG(long val)
{
        return SCALE(clamp_val(val, -128000, 127000), 1, 1000);
}

static inline int TEMP_FROM_REG(s8 val)
{
        return val * 1000;
}

struct smsc47m192_data {
        struct i2c_client *client;
        const struct attribute_group *groups[3];
        struct mutex update_lock;
        bool valid;             /* true if following fields are valid */
        unsigned long last_updated;     /* In jiffies */

        u8 in[8];               /* Register value */
        u8 in_max[8];           /* Register value */
        u8 in_min[8];           /* Register value */
        s8 temp[3];             /* Register value */
        s8 temp_max[3];         /* Register value */
        s8 temp_min[3];         /* Register value */
        s8 temp_offset[3];      /* Register value */
        u16 alarms;             /* Register encoding, combined */
        u8 vid;                 /* Register encoding, combined */
        u8 vrm;
};

static struct smsc47m192_data *smsc47m192_update_device(struct device *dev)
{
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        struct i2c_client *client = data->client;
        int i, config;

        mutex_lock(&data->update_lock);

        if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
         || !data->valid) {
                u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);

                dev_dbg(&client->dev, "Starting smsc47m192 update\n");

                for (i = 0; i <= 7; i++) {
                        data->in[i] = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_IN(i));
                        data->in_min[i] = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_IN_MIN(i));
                        data->in_max[i] = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_IN_MAX(i));
                }
                for (i = 0; i < 3; i++) {
                        data->temp[i] = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_TEMP[i]);
                        data->temp_max[i] = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_TEMP_MAX[i]);
                        data->temp_min[i] = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_TEMP_MIN[i]);
                }
                for (i = 1; i < 3; i++)
                        data->temp_offset[i] = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_TEMP_OFFSET(i));
                /*
                 * first offset is temp_offset[0] if SFR bit 4 is set,
                 * temp_offset[1] otherwise
                 */
                if (sfr & 0x10) {
                        data->temp_offset[0] = data->temp_offset[1];
                        data->temp_offset[1] = 0;
                } else
                        data->temp_offset[0] = 0;

                data->vid = i2c_smbus_read_byte_data(client, SMSC47M192_REG_VID)
                            & 0x0f;
                config = i2c_smbus_read_byte_data(client,
                                                  SMSC47M192_REG_CONFIG);
                if (config & 0x20)
                        data->vid |= (i2c_smbus_read_byte_data(client,
                                        SMSC47M192_REG_VID4) & 0x01) << 4;
                data->alarms = i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_ALARM1) |
                               (i2c_smbus_read_byte_data(client,
                                                SMSC47M192_REG_ALARM2) << 8);

                data->last_updated = jiffies;
                data->valid = true;
        }

        mutex_unlock(&data->update_lock);

        return data;
}

/* Voltages */
static ssize_t in_show(struct device *dev, struct device_attribute *attr,
                       char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", IN_FROM_REG(data->in[nr], nr));
}

static ssize_t in_min_show(struct device *dev, struct device_attribute *attr,
                           char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[nr], nr));
}

static ssize_t in_max_show(struct device *dev, struct device_attribute *attr,
                           char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[nr], nr));
}

static ssize_t in_min_store(struct device *dev, struct device_attribute *attr,
                            const char *buf, size_t count)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        struct i2c_client *client = data->client;
        unsigned long val;
        int err;

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

        mutex_lock(&data->update_lock);
        data->in_min[nr] = IN_TO_REG(val, nr);
        i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MIN(nr),
                                                        data->in_min[nr]);
        mutex_unlock(&data->update_lock);
        return count;
}

static ssize_t in_max_store(struct device *dev, struct device_attribute *attr,
                            const char *buf, size_t count)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        struct i2c_client *client = data->client;
        unsigned long val;
        int err;

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

        mutex_lock(&data->update_lock);
        data->in_max[nr] = IN_TO_REG(val, nr);
        i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MAX(nr),
                                                        data->in_max[nr]);
        mutex_unlock(&data->update_lock);
        return count;
}

static SENSOR_DEVICE_ATTR_RO(in0_input, in, 0);
static SENSOR_DEVICE_ATTR_RW(in0_min, in_min, 0);
static SENSOR_DEVICE_ATTR_RW(in0_max, in_max, 0);
static SENSOR_DEVICE_ATTR_RO(in1_input, in, 1);
static SENSOR_DEVICE_ATTR_RW(in1_min, in_min, 1);
static SENSOR_DEVICE_ATTR_RW(in1_max, in_max, 1);
static SENSOR_DEVICE_ATTR_RO(in2_input, in, 2);
static SENSOR_DEVICE_ATTR_RW(in2_min, in_min, 2);
static SENSOR_DEVICE_ATTR_RW(in2_max, in_max, 2);
static SENSOR_DEVICE_ATTR_RO(in3_input, in, 3);
static SENSOR_DEVICE_ATTR_RW(in3_min, in_min, 3);
static SENSOR_DEVICE_ATTR_RW(in3_max, in_max, 3);
static SENSOR_DEVICE_ATTR_RO(in4_input, in, 4);
static SENSOR_DEVICE_ATTR_RW(in4_min, in_min, 4);
static SENSOR_DEVICE_ATTR_RW(in4_max, in_max, 4);
static SENSOR_DEVICE_ATTR_RO(in5_input, in, 5);
static SENSOR_DEVICE_ATTR_RW(in5_min, in_min, 5);
static SENSOR_DEVICE_ATTR_RW(in5_max, in_max, 5);
static SENSOR_DEVICE_ATTR_RO(in6_input, in, 6);
static SENSOR_DEVICE_ATTR_RW(in6_min, in_min, 6);
static SENSOR_DEVICE_ATTR_RW(in6_max, in_max, 6);
static SENSOR_DEVICE_ATTR_RO(in7_input, in, 7);
static SENSOR_DEVICE_ATTR_RW(in7_min, in_min, 7);
static SENSOR_DEVICE_ATTR_RW(in7_max, in_max, 7);

/* Temperatures */
static ssize_t temp_show(struct device *dev, struct device_attribute *attr,
                         char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
}

static ssize_t temp_min_show(struct device *dev,
                             struct device_attribute *attr, char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_min[nr]));
}

static ssize_t temp_max_show(struct device *dev,
                             struct device_attribute *attr, char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max[nr]));
}

static ssize_t temp_min_store(struct device *dev,
                              struct device_attribute *attr, const char *buf,
                              size_t count)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        struct i2c_client *client = data->client;
        long val;
        int err;

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

        mutex_lock(&data->update_lock);
        data->temp_min[nr] = TEMP_TO_REG(val);
        i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MIN[nr],
                                                data->temp_min[nr]);
        mutex_unlock(&data->update_lock);
        return count;
}

static ssize_t temp_max_store(struct device *dev,
                              struct device_attribute *attr, const char *buf,
                              size_t count)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        struct i2c_client *client = data->client;
        long val;
        int err;

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

        mutex_lock(&data->update_lock);
        data->temp_max[nr] = TEMP_TO_REG(val);
        i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MAX[nr],
                                                data->temp_max[nr]);
        mutex_unlock(&data->update_lock);
        return count;
}

static ssize_t temp_offset_show(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_offset[nr]));
}

static ssize_t temp_offset_store(struct device *dev,
                                 struct device_attribute *attr,
                                 const char *buf, size_t count)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        struct i2c_client *client = data->client;
        u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
        long val;
        int err;

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

        mutex_lock(&data->update_lock);
        data->temp_offset[nr] = TEMP_TO_REG(val);
        if (nr > 1)
                i2c_smbus_write_byte_data(client,
                        SMSC47M192_REG_TEMP_OFFSET(nr), data->temp_offset[nr]);
        else if (data->temp_offset[nr] != 0) {
                /*
                 * offset[0] and offset[1] share the same register,
                 * SFR bit 4 activates offset[0]
                 */
                i2c_smbus_write_byte_data(client, SMSC47M192_REG_SFR,
                                        (sfr & 0xef) | (nr == 0 ? 0x10 : 0));
                data->temp_offset[1-nr] = 0;
                i2c_smbus_write_byte_data(client,
                        SMSC47M192_REG_TEMP_OFFSET(nr), data->temp_offset[nr]);
        } else if ((sfr & 0x10) == (nr == 0 ? 0x10 : 0))
                i2c_smbus_write_byte_data(client,
                                        SMSC47M192_REG_TEMP_OFFSET(nr), 0);
        mutex_unlock(&data->update_lock);
        return count;
}

static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_min, temp_min, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_offset, temp_offset, 0);
static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
static SENSOR_DEVICE_ATTR_RW(temp2_min, temp_min, 1);
static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1);
static SENSOR_DEVICE_ATTR_RW(temp2_offset, temp_offset, 1);
static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
static SENSOR_DEVICE_ATTR_RW(temp3_min, temp_min, 2);
static SENSOR_DEVICE_ATTR_RW(temp3_max, temp_max, 2);
static SENSOR_DEVICE_ATTR_RW(temp3_offset, temp_offset, 2);

/* VID */
static ssize_t cpu0_vid_show(struct device *dev,
                             struct device_attribute *attr, char *buf)
{
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
}
static DEVICE_ATTR_RO(cpu0_vid);

static ssize_t vrm_show(struct device *dev, struct device_attribute *attr,
                char *buf)
{
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        return sprintf(buf, "%d\n", data->vrm);
}

static ssize_t vrm_store(struct device *dev, struct device_attribute *attr,
                         const char *buf, size_t count)
{
        struct smsc47m192_data *data = dev_get_drvdata(dev);
        unsigned long val;
        int err;

        err = kstrtoul(buf, 10, &val);
        if (err)
                return err;
        if (val > 255)
                return -EINVAL;

        data->vrm = val;
        return count;
}
static DEVICE_ATTR_RW(vrm);

/* Alarms */
static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
                          char *buf)
{
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
        int nr = sensor_attr->index;
        struct smsc47m192_data *data = smsc47m192_update_device(dev);
        return sprintf(buf, "%u\n", (data->alarms & nr) ? 1 : 0);
}

static SENSOR_DEVICE_ATTR_RO(temp1_alarm, alarm, 0x0010);
static SENSOR_DEVICE_ATTR_RO(temp2_alarm, alarm, 0x0020);
static SENSOR_DEVICE_ATTR_RO(temp3_alarm, alarm, 0x0040);
static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 0x4000);
static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 0x8000);
static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0x0001);
static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 0x0002);
static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 0x0004);
static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 0x0008);
static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 0x0100);
static SENSOR_DEVICE_ATTR_RO(in5_alarm, alarm, 0x0200);
static SENSOR_DEVICE_ATTR_RO(in6_alarm, alarm, 0x0400);
static SENSOR_DEVICE_ATTR_RO(in7_alarm, alarm, 0x0800);

static struct attribute *smsc47m192_attributes[] = {
        &sensor_dev_attr_in0_input.dev_attr.attr,
        &sensor_dev_attr_in0_min.dev_attr.attr,
        &sensor_dev_attr_in0_max.dev_attr.attr,
        &sensor_dev_attr_in0_alarm.dev_attr.attr,
        &sensor_dev_attr_in1_input.dev_attr.attr,
        &sensor_dev_attr_in1_min.dev_attr.attr,
        &sensor_dev_attr_in1_max.dev_attr.attr,
        &sensor_dev_attr_in1_alarm.dev_attr.attr,
        &sensor_dev_attr_in2_input.dev_attr.attr,
        &sensor_dev_attr_in2_min.dev_attr.attr,
        &sensor_dev_attr_in2_max.dev_attr.attr,
        &sensor_dev_attr_in2_alarm.dev_attr.attr,
        &sensor_dev_attr_in3_input.dev_attr.attr,
        &sensor_dev_attr_in3_min.dev_attr.attr,
        &sensor_dev_attr_in3_max.dev_attr.attr,
        &sensor_dev_attr_in3_alarm.dev_attr.attr,
        &sensor_dev_attr_in5_input.dev_attr.attr,
        &sensor_dev_attr_in5_min.dev_attr.attr,
        &sensor_dev_attr_in5_max.dev_attr.attr,
        &sensor_dev_attr_in5_alarm.dev_attr.attr,
        &sensor_dev_attr_in6_input.dev_attr.attr,
        &sensor_dev_attr_in6_min.dev_attr.attr,
        &sensor_dev_attr_in6_max.dev_attr.attr,
        &sensor_dev_attr_in6_alarm.dev_attr.attr,
        &sensor_dev_attr_in7_input.dev_attr.attr,
        &sensor_dev_attr_in7_min.dev_attr.attr,
        &sensor_dev_attr_in7_max.dev_attr.attr,
        &sensor_dev_attr_in7_alarm.dev_attr.attr,

        &sensor_dev_attr_temp1_input.dev_attr.attr,
        &sensor_dev_attr_temp1_max.dev_attr.attr,
        &sensor_dev_attr_temp1_min.dev_attr.attr,
        &sensor_dev_attr_temp1_offset.dev_attr.attr,
        &sensor_dev_attr_temp1_alarm.dev_attr.attr,
        &sensor_dev_attr_temp2_input.dev_attr.attr,
        &sensor_dev_attr_temp2_max.dev_attr.attr,
        &sensor_dev_attr_temp2_min.dev_attr.attr,
        &sensor_dev_attr_temp2_offset.dev_attr.attr,
        &sensor_dev_attr_temp2_alarm.dev_attr.attr,
        &sensor_dev_attr_temp2_fault.dev_attr.attr,
        &sensor_dev_attr_temp3_input.dev_attr.attr,
        &sensor_dev_attr_temp3_max.dev_attr.attr,
        &sensor_dev_attr_temp3_min.dev_attr.attr,
        &sensor_dev_attr_temp3_offset.dev_attr.attr,
        &sensor_dev_attr_temp3_alarm.dev_attr.attr,
        &sensor_dev_attr_temp3_fault.dev_attr.attr,

        &dev_attr_cpu0_vid.attr,
        &dev_attr_vrm.attr,
        NULL
};

static const struct attribute_group smsc47m192_group = {
        .attrs = smsc47m192_attributes,
};

static struct attribute *smsc47m192_attributes_in4[] = {
        &sensor_dev_attr_in4_input.dev_attr.attr,
        &sensor_dev_attr_in4_min.dev_attr.attr,
        &sensor_dev_attr_in4_max.dev_attr.attr,
        &sensor_dev_attr_in4_alarm.dev_attr.attr,
        NULL
};

static const struct attribute_group smsc47m192_group_in4 = {
        .attrs = smsc47m192_attributes_in4,
};

static void smsc47m192_init_client(struct i2c_client *client)
{
        int i;
        u8 config = i2c_smbus_read_byte_data(client, SMSC47M192_REG_CONFIG);
        u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);

        /* select cycle mode (pause 1 sec between updates) */
        i2c_smbus_write_byte_data(client, SMSC47M192_REG_SFR,
                                                (sfr & 0xfd) | 0x02);
        if (!(config & 0x01)) {
                /* initialize alarm limits */
                for (i = 0; i < 8; i++) {
                        i2c_smbus_write_byte_data(client,
                                SMSC47M192_REG_IN_MIN(i), 0);
                        i2c_smbus_write_byte_data(client,
                                SMSC47M192_REG_IN_MAX(i), 0xff);
                }
                for (i = 0; i < 3; i++) {
                        i2c_smbus_write_byte_data(client,
                                SMSC47M192_REG_TEMP_MIN[i], 0x80);
                        i2c_smbus_write_byte_data(client,
                                SMSC47M192_REG_TEMP_MAX[i], 0x7f);
                }

                /* start monitoring */
                i2c_smbus_write_byte_data(client, SMSC47M192_REG_CONFIG,
                                                (config & 0xf7) | 0x01);
        }
}

/* Return 0 if detection is successful, -ENODEV otherwise */
static int smsc47m192_detect(struct i2c_client *client,
                             struct i2c_board_info *info)
{
        struct i2c_adapter *adapter = client->adapter;
        int version;

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

        /* Detection criteria from sensors_detect script */
        version = i2c_smbus_read_byte_data(client, SMSC47M192_REG_VERSION);
        if (i2c_smbus_read_byte_data(client,
                                SMSC47M192_REG_COMPANY_ID) == 0x55
         && (version & 0xf0) == 0x20
         && (i2c_smbus_read_byte_data(client,
                                SMSC47M192_REG_VID) & 0x70) == 0x00
         && (i2c_smbus_read_byte_data(client,
                                SMSC47M192_REG_VID4) & 0xfe) == 0x80) {
                dev_info(&adapter->dev,
                         "found SMSC47M192 or compatible, "
                         "version 2, stepping A%d\n", version & 0x0f);
        } else {
                dev_dbg(&adapter->dev,
                        "SMSC47M192 detection failed at 0x%02x\n",
                        client->addr);
                return -ENODEV;
        }

        strscpy(info->type, "smsc47m192", I2C_NAME_SIZE);

        return 0;
}

static int smsc47m192_probe(struct i2c_client *client)
{
        struct device *dev = &client->dev;
        struct device *hwmon_dev;
        struct smsc47m192_data *data;
        int config;

        data = devm_kzalloc(dev, sizeof(struct smsc47m192_data), GFP_KERNEL);
        if (!data)
                return -ENOMEM;

        data->client = client;
        data->vrm = vid_which_vrm();
        mutex_init(&data->update_lock);

        /* Initialize the SMSC47M192 chip */
        smsc47m192_init_client(client);

        /* sysfs hooks */
        data->groups[0] = &smsc47m192_group;
        /* Pin 110 is either in4 (+12V) or VID4 */
        config = i2c_smbus_read_byte_data(client, SMSC47M192_REG_CONFIG);
        if (!(config & 0x20))
                data->groups[1] = &smsc47m192_group_in4;

        hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
                                                           data, data->groups);
        return PTR_ERR_OR_ZERO(hwmon_dev);
}

static const struct i2c_device_id smsc47m192_id[] = {
        { "smsc47m192" },
        { }
};
MODULE_DEVICE_TABLE(i2c, smsc47m192_id);

static struct i2c_driver smsc47m192_driver = {
        .class          = I2C_CLASS_HWMON,
        .driver = {
                .name   = "smsc47m192",
        },
        .probe          = smsc47m192_probe,
        .id_table       = smsc47m192_id,
        .detect         = smsc47m192_detect,
        .address_list   = normal_i2c,
};

module_i2c_driver(smsc47m192_driver);

MODULE_AUTHOR("Hartmut Rick <linux@rick.claranet.de>");
MODULE_DESCRIPTION("SMSC47M192 driver");
MODULE_LICENSE("GPL");