drivers/hwmon/emc6w201.c

   1 /*
   2  * emc6w201.c - Hardware monitoring driver for the SMSC EMC6W201
   3  * Copyright (C) 2011  Jean Delvare <khali@linux-fr.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/delay.h>
  22 #include <linux/init.h>
  23 #include <linux/slab.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/i2c.h>
  26 #include <linux/hwmon.h>
  27 #include <linux/hwmon-sysfs.h>
  28 #include <linux/err.h>
  29 #include <linux/mutex.h>
  30
  31 /*
  32  * Addresses to scan
  33  */
  34
  35 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };
  36
  37 /*
  38  * The EMC6W201 registers
  39  */
  40
  41 #define EMC6W201_REG_IN(nr)             (0x20 + (nr))
  42 #define EMC6W201_REG_TEMP(nr)           (0x26 + (nr))
  43 #define EMC6W201_REG_FAN(nr)            (0x2C + (nr) * 2)
  44 #define EMC6W201_REG_COMPANY            0x3E
  45 #define EMC6W201_REG_VERSTEP            0x3F
  46 #define EMC6W201_REG_CONFIG             0x40
  47 #define EMC6W201_REG_IN_LOW(nr)         (0x4A + (nr) * 2)
  48 #define EMC6W201_REG_IN_HIGH(nr)        (0x4B + (nr) * 2)
  49 #define EMC6W201_REG_TEMP_LOW(nr)       (0x56 + (nr) * 2)
  50 #define EMC6W201_REG_TEMP_HIGH(nr)      (0x57 + (nr) * 2)
  51 #define EMC6W201_REG_FAN_MIN(nr)        (0x62 + (nr) * 2)
  52
  53 enum { input, min, max } subfeature;
  54
  55 /*
  56  * Per-device data
  57  */
  58
  59 struct emc6w201_data {
  60         struct device *hwmon_dev;
  61         struct mutex update_lock;
  62         char valid; /* zero until following fields are valid */
  63         unsigned long last_updated; /* in jiffies */
  64
  65         /* registers values */
  66         u8 in[3][6];
  67         s8 temp[3][6];
  68         u16 fan[2][5];
  69 };
  70
  71 /*
  72  * Combine LSB and MSB registers in a single value
  73  * Locking: must be called with data->update_lock held
  74  */
  75 static u16 emc6w201_read16(struct i2c_client *client, u8 reg)
  76 {
  77         int lsb, msb;
  78
  79         lsb = i2c_smbus_read_byte_data(client, reg);
  80         msb = i2c_smbus_read_byte_data(client, reg + 1);
  81         if (unlikely(lsb < 0 || msb < 0)) {
  82                 dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
  83                         16, "read", reg);
  84                 return 0xFFFF;  /* Arbitrary value */
  85         }
  86
  87         return (msb << 8) | lsb;
  88 }
  89
  90 /*
  91  * Write 16-bit value to LSB and MSB registers
  92  * Locking: must be called with data->update_lock held
  93  */
  94 static int emc6w201_write16(struct i2c_client *client, u8 reg, u16 val)
  95 {
  96         int err;
  97
  98         err = i2c_smbus_write_byte_data(client, reg, val & 0xff);
  99         if (likely(!err))
 100                 err = i2c_smbus_write_byte_data(client, reg + 1, val >> 8);
 101         if (unlikely(err < 0))
 102                 dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
 103                         16, "write", reg);
 104
 105         return err;
 106 }
 107
 108 /* Read 8-bit value from register */
 109 static u8 emc6w201_read8(struct i2c_client *client, u8 reg)
 110 {
 111         int val;
 112
 113         val = i2c_smbus_read_byte_data(client, reg);
 114         if (unlikely(val < 0)) {
 115                 dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
 116                         8, "read", reg);
 117                 return 0x00;    /* Arbitrary value */
 118         }
 119
 120         return val;
 121 }
 122
 123 /* Write 8-bit value to register */
 124 static int emc6w201_write8(struct i2c_client *client, u8 reg, u8 val)
 125 {
 126         int err;
 127
 128         err = i2c_smbus_write_byte_data(client, reg, val);
 129         if (unlikely(err < 0))
 130                 dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",
 131                         8, "write", reg);
 132
 133         return err;
 134 }
 135
 136 static struct emc6w201_data *emc6w201_update_device(struct device *dev)
 137 {
 138         struct i2c_client *client = to_i2c_client(dev);
 139         struct emc6w201_data *data = i2c_get_clientdata(client);
 140         int nr;
 141
 142         mutex_lock(&data->update_lock);
 143
 144         if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
 145                 for (nr = 0; nr < 6; nr++) {
 146                         data->in[input][nr] =
 147                                 emc6w201_read8(client,
 148                                                 EMC6W201_REG_IN(nr));
 149                         data->in[min][nr] =
 150                                 emc6w201_read8(client,
 151                                                 EMC6W201_REG_IN_LOW(nr));
 152                         data->in[max][nr] =
 153                                 emc6w201_read8(client,
 154                                                 EMC6W201_REG_IN_HIGH(nr));
 155                 }
 156
 157                 for (nr = 0; nr < 6; nr++) {
 158                         data->temp[input][nr] =
 159                                 emc6w201_read8(client,
 160                                                 EMC6W201_REG_TEMP(nr));
 161                         data->temp[min][nr] =
 162                                 emc6w201_read8(client,
 163                                                 EMC6W201_REG_TEMP_LOW(nr));
 164                         data->temp[max][nr] =
 165                                 emc6w201_read8(client,
 166                                                 EMC6W201_REG_TEMP_HIGH(nr));
 167                 }
 168
 169                 for (nr = 0; nr < 5; nr++) {
 170                         data->fan[input][nr] =
 171                                 emc6w201_read16(client,
 172                                                 EMC6W201_REG_FAN(nr));
 173                         data->fan[min][nr] =
 174                                 emc6w201_read16(client,
 175                                                 EMC6W201_REG_FAN_MIN(nr));
 176                 }
 177
 178                 data->last_updated = jiffies;
 179                 data->valid = 1;
 180         }
 181
 182         mutex_unlock(&data->update_lock);
 183
 184         return data;
 185 }
 186
 187 /*
 188  * Sysfs callback functions
 189  */
 190
 191 static const u16 nominal_mv[6] = { 2500, 1500, 3300, 5000, 1500, 1500 };
 192
 193 static ssize_t show_in(struct device *dev, struct device_attribute *devattr,
 194         char *buf)
 195 {
 196         struct emc6w201_data *data = emc6w201_update_device(dev);
 197         int sf = to_sensor_dev_attr_2(devattr)->index;
 198         int nr = to_sensor_dev_attr_2(devattr)->nr;
 199
 200         return sprintf(buf, "%u\n",
 201                        (unsigned)data->in[sf][nr] * nominal_mv[nr] / 0xC0);
 202 }
 203
 204 static ssize_t set_in(struct device *dev, struct device_attribute *devattr,
 205                       const char *buf, size_t count)
 206 {
 207         struct i2c_client *client = to_i2c_client(dev);
 208         struct emc6w201_data *data = i2c_get_clientdata(client);
 209         int sf = to_sensor_dev_attr_2(devattr)->index;
 210         int nr = to_sensor_dev_attr_2(devattr)->nr;
 211         int err;
 212         long val;
 213         u8 reg;
 214
 215         err = kstrtol(buf, 10, &val);
 216         if (err < 0)
 217                 return err;
 218
 219         val = DIV_ROUND_CLOSEST(val * 0xC0, nominal_mv[nr]);
 220         reg = (sf == min) ? EMC6W201_REG_IN_LOW(nr)
 221                           : EMC6W201_REG_IN_HIGH(nr);
 222
 223         mutex_lock(&data->update_lock);
 224         data->in[sf][nr] = SENSORS_LIMIT(val, 0, 255);
 225         err = emc6w201_write8(client, reg, data->in[sf][nr]);
 226         mutex_unlock(&data->update_lock);
 227
 228         return err < 0 ? err : count;
 229 }
 230
 231 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
 232         char *buf)
 233 {
 234         struct emc6w201_data *data = emc6w201_update_device(dev);
 235         int sf = to_sensor_dev_attr_2(devattr)->index;
 236         int nr = to_sensor_dev_attr_2(devattr)->nr;
 237
 238         return sprintf(buf, "%d\n", (int)data->temp[sf][nr] * 1000);
 239 }
 240
 241 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
 242                         const char *buf, size_t count)
 243 {
 244         struct i2c_client *client = to_i2c_client(dev);
 245         struct emc6w201_data *data = i2c_get_clientdata(client);
 246         int sf = to_sensor_dev_attr_2(devattr)->index;
 247         int nr = to_sensor_dev_attr_2(devattr)->nr;
 248         int err;
 249         long val;
 250         u8 reg;
 251
 252         err = kstrtol(buf, 10, &val);
 253         if (err < 0)
 254                 return err;
 255
 256         val /= 1000;
 257         reg = (sf == min) ? EMC6W201_REG_TEMP_LOW(nr)
 258                           : EMC6W201_REG_TEMP_HIGH(nr);
 259
 260         mutex_lock(&data->update_lock);
 261         data->temp[sf][nr] = SENSORS_LIMIT(val, -127, 128);
 262         err = emc6w201_write8(client, reg, data->temp[sf][nr]);
 263         mutex_unlock(&data->update_lock);
 264
 265         return err < 0 ? err : count;
 266 }
 267
 268 static ssize_t show_fan(struct device *dev, struct device_attribute *devattr,
 269         char *buf)
 270 {
 271         struct emc6w201_data *data = emc6w201_update_device(dev);
 272         int sf = to_sensor_dev_attr_2(devattr)->index;
 273         int nr = to_sensor_dev_attr_2(devattr)->nr;
 274         unsigned rpm;
 275
 276         if (data->fan[sf][nr] == 0 || data->fan[sf][nr] == 0xFFFF)
 277                 rpm = 0;
 278         else
 279                 rpm = 5400000U / data->fan[sf][nr];
 280
 281         return sprintf(buf, "%u\n", rpm);
 282 }
 283
 284 static ssize_t set_fan(struct device *dev, struct device_attribute *devattr,
 285                        const char *buf, size_t count)
 286 {
 287         struct i2c_client *client = to_i2c_client(dev);
 288         struct emc6w201_data *data = i2c_get_clientdata(client);
 289         int sf = to_sensor_dev_attr_2(devattr)->index;
 290         int nr = to_sensor_dev_attr_2(devattr)->nr;
 291         int err;
 292         unsigned long val;
 293
 294         err = kstrtoul(buf, 10, &val);
 295         if (err < 0)
 296                 return err;
 297
 298         if (val == 0) {
 299                 val = 0xFFFF;
 300         } else {
 301                 val = DIV_ROUND_CLOSEST(5400000U, val);
 302                 val = SENSORS_LIMIT(val, 0, 0xFFFE);
 303         }
 304
 305         mutex_lock(&data->update_lock);
 306         data->fan[sf][nr] = val;
 307         err = emc6w201_write16(client, EMC6W201_REG_FAN_MIN(nr),
 308                                data->fan[sf][nr]);
 309         mutex_unlock(&data->update_lock);
 310
 311         return err < 0 ? err : count;
 312 }
 313
 314 static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO, show_in, NULL, 0, input);
 315 static SENSOR_DEVICE_ATTR_2(in0_min, S_IRUGO | S_IWUSR, show_in, set_in,
 316                             0, min);
 317 static SENSOR_DEVICE_ATTR_2(in0_max, S_IRUGO | S_IWUSR, show_in, set_in,
 318                             0, max);
 319 static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO, show_in, NULL, 1, input);
 320 static SENSOR_DEVICE_ATTR_2(in1_min, S_IRUGO | S_IWUSR, show_in, set_in,
 321                             1, min);
 322 static SENSOR_DEVICE_ATTR_2(in1_max, S_IRUGO | S_IWUSR, show_in, set_in,
 323                             1, max);
 324 static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO, show_in, NULL, 2, input);
 325 static SENSOR_DEVICE_ATTR_2(in2_min, S_IRUGO | S_IWUSR, show_in, set_in,
 326                             2, min);
 327 static SENSOR_DEVICE_ATTR_2(in2_max, S_IRUGO | S_IWUSR, show_in, set_in,
 328                             2, max);
 329 static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO, show_in, NULL, 3, input);
 330 static SENSOR_DEVICE_ATTR_2(in3_min, S_IRUGO | S_IWUSR, show_in, set_in,
 331                             3, min);
 332 static SENSOR_DEVICE_ATTR_2(in3_max, S_IRUGO | S_IWUSR, show_in, set_in,
 333                             3, max);
 334 static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO, show_in, NULL, 4, input);
 335 static SENSOR_DEVICE_ATTR_2(in4_min, S_IRUGO | S_IWUSR, show_in, set_in,
 336                             4, min);
 337 static SENSOR_DEVICE_ATTR_2(in4_max, S_IRUGO | S_IWUSR, show_in, set_in,
 338                             4, max);
 339 static SENSOR_DEVICE_ATTR_2(in5_input, S_IRUGO, show_in, NULL, 5, input);
 340 static SENSOR_DEVICE_ATTR_2(in5_min, S_IRUGO | S_IWUSR, show_in, set_in,
 341                             5, min);
 342 static SENSOR_DEVICE_ATTR_2(in5_max, S_IRUGO | S_IWUSR, show_in, set_in,
 343                             5, max);
 344
 345 static SENSOR_DEVICE_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0, input);
 346 static SENSOR_DEVICE_ATTR_2(temp1_min, S_IRUGO | S_IWUSR, show_temp, set_temp,
 347                             0, min);
 348 static SENSOR_DEVICE_ATTR_2(temp1_max, S_IRUGO | S_IWUSR, show_temp, set_temp,
 349                             0, max);
 350 static SENSOR_DEVICE_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 1, input);
 351 static SENSOR_DEVICE_ATTR_2(temp2_min, S_IRUGO | S_IWUSR, show_temp, set_temp,
 352                             1, min);
 353 static SENSOR_DEVICE_ATTR_2(temp2_max, S_IRUGO | S_IWUSR, show_temp, set_temp,
 354                             1, max);
 355 static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp, NULL, 2, input);
 356 static SENSOR_DEVICE_ATTR_2(temp3_min, S_IRUGO | S_IWUSR, show_temp, set_temp,
 357                             2, min);
 358 static SENSOR_DEVICE_ATTR_2(temp3_max, S_IRUGO | S_IWUSR, show_temp, set_temp,
 359                             2, max);
 360 static SENSOR_DEVICE_ATTR_2(temp4_input, S_IRUGO, show_temp, NULL, 3, input);
 361 static SENSOR_DEVICE_ATTR_2(temp4_min, S_IRUGO | S_IWUSR, show_temp, set_temp,
 362                             3, min);
 363 static SENSOR_DEVICE_ATTR_2(temp4_max, S_IRUGO | S_IWUSR, show_temp, set_temp,
 364                             3, max);
 365 static SENSOR_DEVICE_ATTR_2(temp5_input, S_IRUGO, show_temp, NULL, 4, input);
 366 static SENSOR_DEVICE_ATTR_2(temp5_min, S_IRUGO | S_IWUSR, show_temp, set_temp,
 367                             4, min);
 368 static SENSOR_DEVICE_ATTR_2(temp5_max, S_IRUGO | S_IWUSR, show_temp, set_temp,
 369                             4, max);
 370 static SENSOR_DEVICE_ATTR_2(temp6_input, S_IRUGO, show_temp, NULL, 5, input);
 371 static SENSOR_DEVICE_ATTR_2(temp6_min, S_IRUGO | S_IWUSR, show_temp, set_temp,
 372                             5, min);
 373 static SENSOR_DEVICE_ATTR_2(temp6_max, S_IRUGO | S_IWUSR, show_temp, set_temp,
 374                             5, max);
 375
 376 static SENSOR_DEVICE_ATTR_2(fan1_input, S_IRUGO, show_fan, NULL, 0, input);
 377 static SENSOR_DEVICE_ATTR_2(fan1_min, S_IRUGO | S_IWUSR, show_fan, set_fan,
 378                             0, min);
 379 static SENSOR_DEVICE_ATTR_2(fan2_input, S_IRUGO, show_fan, NULL, 1, input);
 380 static SENSOR_DEVICE_ATTR_2(fan2_min, S_IRUGO | S_IWUSR, show_fan, set_fan,
 381                             1, min);
 382 static SENSOR_DEVICE_ATTR_2(fan3_input, S_IRUGO, show_fan, NULL, 2, input);
 383 static SENSOR_DEVICE_ATTR_2(fan3_min, S_IRUGO | S_IWUSR, show_fan, set_fan,
 384                             2, min);
 385 static SENSOR_DEVICE_ATTR_2(fan4_input, S_IRUGO, show_fan, NULL, 3, input);
 386 static SENSOR_DEVICE_ATTR_2(fan4_min, S_IRUGO | S_IWUSR, show_fan, set_fan,
 387                             3, min);
 388 static SENSOR_DEVICE_ATTR_2(fan5_input, S_IRUGO, show_fan, NULL, 4, input);
 389 static SENSOR_DEVICE_ATTR_2(fan5_min, S_IRUGO | S_IWUSR, show_fan, set_fan,
 390                             4, min);
 391
 392 static struct attribute *emc6w201_attributes[] = {
 393         &sensor_dev_attr_in0_input.dev_attr.attr,
 394         &sensor_dev_attr_in0_min.dev_attr.attr,
 395         &sensor_dev_attr_in0_max.dev_attr.attr,
 396         &sensor_dev_attr_in1_input.dev_attr.attr,
 397         &sensor_dev_attr_in1_min.dev_attr.attr,
 398         &sensor_dev_attr_in1_max.dev_attr.attr,
 399         &sensor_dev_attr_in2_input.dev_attr.attr,
 400         &sensor_dev_attr_in2_min.dev_attr.attr,
 401         &sensor_dev_attr_in2_max.dev_attr.attr,
 402         &sensor_dev_attr_in3_input.dev_attr.attr,
 403         &sensor_dev_attr_in3_min.dev_attr.attr,
 404         &sensor_dev_attr_in3_max.dev_attr.attr,
 405         &sensor_dev_attr_in4_input.dev_attr.attr,
 406         &sensor_dev_attr_in4_min.dev_attr.attr,
 407         &sensor_dev_attr_in4_max.dev_attr.attr,
 408         &sensor_dev_attr_in5_input.dev_attr.attr,
 409         &sensor_dev_attr_in5_min.dev_attr.attr,
 410         &sensor_dev_attr_in5_max.dev_attr.attr,
 411
 412         &sensor_dev_attr_temp1_input.dev_attr.attr,
 413         &sensor_dev_attr_temp1_min.dev_attr.attr,
 414         &sensor_dev_attr_temp1_max.dev_attr.attr,
 415         &sensor_dev_attr_temp2_input.dev_attr.attr,
 416         &sensor_dev_attr_temp2_min.dev_attr.attr,
 417         &sensor_dev_attr_temp2_max.dev_attr.attr,
 418         &sensor_dev_attr_temp3_input.dev_attr.attr,
 419         &sensor_dev_attr_temp3_min.dev_attr.attr,
 420         &sensor_dev_attr_temp3_max.dev_attr.attr,
 421         &sensor_dev_attr_temp4_input.dev_attr.attr,
 422         &sensor_dev_attr_temp4_min.dev_attr.attr,
 423         &sensor_dev_attr_temp4_max.dev_attr.attr,
 424         &sensor_dev_attr_temp5_input.dev_attr.attr,
 425         &sensor_dev_attr_temp5_min.dev_attr.attr,
 426         &sensor_dev_attr_temp5_max.dev_attr.attr,
 427         &sensor_dev_attr_temp6_input.dev_attr.attr,
 428         &sensor_dev_attr_temp6_min.dev_attr.attr,
 429         &sensor_dev_attr_temp6_max.dev_attr.attr,
 430
 431         &sensor_dev_attr_fan1_input.dev_attr.attr,
 432         &sensor_dev_attr_fan1_min.dev_attr.attr,
 433         &sensor_dev_attr_fan2_input.dev_attr.attr,
 434         &sensor_dev_attr_fan2_min.dev_attr.attr,
 435         &sensor_dev_attr_fan3_input.dev_attr.attr,
 436         &sensor_dev_attr_fan3_min.dev_attr.attr,
 437         &sensor_dev_attr_fan4_input.dev_attr.attr,
 438         &sensor_dev_attr_fan4_min.dev_attr.attr,
 439         &sensor_dev_attr_fan5_input.dev_attr.attr,
 440         &sensor_dev_attr_fan5_min.dev_attr.attr,
 441         NULL
 442 };
 443
 444 static const struct attribute_group emc6w201_group = {
 445         .attrs = emc6w201_attributes,
 446 };
 447
 448 /*
 449  * Driver interface
 450  */
 451
 452 /* Return 0 if detection is successful, -ENODEV otherwise */
 453 static int emc6w201_detect(struct i2c_client *client,
 454                            struct i2c_board_info *info)
 455 {
 456         struct i2c_adapter *adapter = client->adapter;
 457         int company, verstep, config;
 458
 459         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 460                 return -ENODEV;
 461
 462         /* Identification */
 463         company = i2c_smbus_read_byte_data(client, EMC6W201_REG_COMPANY);
 464         if (company != 0x5C)
 465                 return -ENODEV;
 466         verstep = i2c_smbus_read_byte_data(client, EMC6W201_REG_VERSTEP);
 467         if (verstep < 0 || (verstep & 0xF0) != 0xB0)
 468                 return -ENODEV;
 469         if ((verstep & 0x0F) > 2) {
 470                 dev_dbg(&client->dev, "Unknwown EMC6W201 stepping %d\n",
 471                         verstep & 0x0F);
 472                 return -ENODEV;
 473         }
 474
 475         /* Check configuration */
 476         config = i2c_smbus_read_byte_data(client, EMC6W201_REG_CONFIG);
 477         if (config < 0 || (config & 0xF4) != 0x04)
 478                 return -ENODEV;
 479         if (!(config & 0x01)) {
 480                 dev_err(&client->dev, "Monitoring not enabled\n");
 481                 return -ENODEV;
 482         }
 483
 484         strlcpy(info->type, "emc6w201", I2C_NAME_SIZE);
 485
 486         return 0;
 487 }
 488
 489 static int emc6w201_probe(struct i2c_client *client,
 490                           const struct i2c_device_id *id)
 491 {
 492         struct emc6w201_data *data;
 493         int err;
 494
 495         data = devm_kzalloc(&client->dev, sizeof(struct emc6w201_data),
 496                             GFP_KERNEL);
 497         if (!data)
 498                 return -ENOMEM;
 499
 500         i2c_set_clientdata(client, data);
 501         mutex_init(&data->update_lock);
 502
 503         /* Create sysfs attribute */
 504         err = sysfs_create_group(&client->dev.kobj, &emc6w201_group);
 505         if (err)
 506                 return err;
 507
 508         /* Expose as a hwmon device */
 509         data->hwmon_dev = hwmon_device_register(&client->dev);
 510         if (IS_ERR(data->hwmon_dev)) {
 511                 err = PTR_ERR(data->hwmon_dev);
 512                 goto exit_remove;
 513         }
 514
 515         return 0;
 516
 517  exit_remove:
 518         sysfs_remove_group(&client->dev.kobj, &emc6w201_group);
 519         return err;
 520 }
 521
 522 static int emc6w201_remove(struct i2c_client *client)
 523 {
 524         struct emc6w201_data *data = i2c_get_clientdata(client);
 525
 526         hwmon_device_unregister(data->hwmon_dev);
 527         sysfs_remove_group(&client->dev.kobj, &emc6w201_group);
 528
 529         return 0;
 530 }
 531
 532 static const struct i2c_device_id emc6w201_id[] = {
 533         { "emc6w201", 0 },
 534         { }
 535 };
 536 MODULE_DEVICE_TABLE(i2c, emc6w201_id);
 537
 538 static struct i2c_driver emc6w201_driver = {
 539         .class          = I2C_CLASS_HWMON,
 540         .driver = {
 541                 .name   = "emc6w201",
 542         },
 543         .probe          = emc6w201_probe,
 544         .remove         = emc6w201_remove,
 545         .id_table       = emc6w201_id,
 546         .detect         = emc6w201_detect,
 547         .address_list   = normal_i2c,
 548 };
 549
 550 module_i2c_driver(emc6w201_driver);
 551
 552 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
 553 MODULE_DESCRIPTION("SMSC EMC6W201 hardware monitoring driver");
 554 MODULE_LICENSE("GPL");