drivers/hwmon/nct7802.c

   1 /*
   2  * nct7802 - Driver for Nuvoton NCT7802Y
   3  *
   4  * Copyright (C) 2014  Guenter Roeck <linux@roeck-us.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  */
  16
  17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  18
  19 #include <linux/err.h>
  20 #include <linux/i2c.h>
  21 #include <linux/init.h>
  22 #include <linux/hwmon.h>
  23 #include <linux/hwmon-sysfs.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/module.h>
  26 #include <linux/mutex.h>
  27 #include <linux/regmap.h>
  28 #include <linux/slab.h>
  29
  30 #define DRVNAME "nct7802"
  31
  32 static const u8 REG_VOLTAGE[5] = { 0x09, 0x0a, 0x0c, 0x0d, 0x0e };
  33
  34 static const u8 REG_VOLTAGE_LIMIT_LSB[2][5] = {
  35         { 0x40, 0x00, 0x42, 0x44, 0x46 },
  36         { 0x3f, 0x00, 0x41, 0x43, 0x45 },
  37 };
  38
  39 static const u8 REG_VOLTAGE_LIMIT_MSB[5] = { 0x48, 0x00, 0x47, 0x47, 0x48 };
  40
  41 static const u8 REG_VOLTAGE_LIMIT_MSB_SHIFT[2][5] = {
  42         { 0, 0, 4, 0, 4 },
  43         { 2, 0, 6, 2, 6 },
  44 };
  45
  46 #define REG_BANK                0x00
  47 #define REG_TEMP_LSB            0x05
  48 #define REG_TEMP_PECI_LSB       0x08
  49 #define REG_VOLTAGE_LOW         0x0f
  50 #define REG_FANCOUNT_LOW        0x13
  51 #define REG_START               0x21
  52 #define REG_MODE                0x22 /* 7.2.32 Mode Selection Register */
  53 #define REG_PECI_ENABLE         0x23
  54 #define REG_FAN_ENABLE          0x24
  55 #define REG_VMON_ENABLE         0x25
  56 #define REG_PWM(x)              (0x60 + (x))
  57 #define REG_SMARTFAN_EN(x)      (0x64 + (x) / 2)
  58 #define SMARTFAN_EN_SHIFT(x)    ((x) % 2 * 4)
  59 #define REG_VENDOR_ID           0xfd
  60 #define REG_CHIP_ID             0xfe
  61 #define REG_VERSION_ID          0xff
  62
  63 /*
  64  * Data structures and manipulation thereof
  65  */
  66
  67 struct nct7802_data {
  68         struct regmap *regmap;
  69         struct mutex access_lock; /* for multi-byte read and write operations */
  70 };
  71
  72 static ssize_t temp_type_show(struct device *dev,
  73                               struct device_attribute *attr, char *buf)
  74 {
  75         struct nct7802_data *data = dev_get_drvdata(dev);
  76         struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
  77         unsigned int mode;
  78         int ret;
  79
  80         ret = regmap_read(data->regmap, REG_MODE, &mode);
  81         if (ret < 0)
  82                 return ret;
  83
  84         return sprintf(buf, "%u\n", (mode >> (2 * sattr->index) & 3) + 2);
  85 }
  86
  87 static ssize_t temp_type_store(struct device *dev,
  88                                struct device_attribute *attr, const char *buf,
  89                                size_t count)
  90 {
  91         struct nct7802_data *data = dev_get_drvdata(dev);
  92         struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
  93         unsigned int type;
  94         int err;
  95
  96         err = kstrtouint(buf, 0, &type);
  97         if (err < 0)
  98                 return err;
  99         if (sattr->index == 2 && type != 4) /* RD3 */
 100                 return -EINVAL;
 101         if (type < 3 || type > 4)
 102                 return -EINVAL;
 103         err = regmap_update_bits(data->regmap, REG_MODE,
 104                         3 << 2 * sattr->index, (type - 2) << 2 * sattr->index);
 105         return err ? : count;
 106 }
 107
 108 static ssize_t pwm_mode_show(struct device *dev,
 109                              struct device_attribute *attr, char *buf)
 110 {
 111         struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
 112         struct nct7802_data *data = dev_get_drvdata(dev);
 113         unsigned int regval;
 114         int ret;
 115
 116         if (sattr->index > 1)
 117                 return sprintf(buf, "1\n");
 118
 119         ret = regmap_read(data->regmap, 0x5E, &regval);
 120         if (ret < 0)
 121                 return ret;
 122
 123         return sprintf(buf, "%u\n", !(regval & (1 << sattr->index)));
 124 }
 125
 126 static ssize_t pwm_show(struct device *dev, struct device_attribute *devattr,
 127                         char *buf)
 128 {
 129         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 130         struct nct7802_data *data = dev_get_drvdata(dev);
 131         unsigned int val;
 132         int ret;
 133
 134         if (!attr->index)
 135                 return sprintf(buf, "255\n");
 136
 137         ret = regmap_read(data->regmap, attr->index, &val);
 138         if (ret < 0)
 139                 return ret;
 140
 141         return sprintf(buf, "%d\n", val);
 142 }
 143
 144 static ssize_t pwm_store(struct device *dev, struct device_attribute *devattr,
 145                          const char *buf, size_t count)
 146 {
 147         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 148         struct nct7802_data *data = dev_get_drvdata(dev);
 149         int err;
 150         u8 val;
 151
 152         err = kstrtou8(buf, 0, &val);
 153         if (err < 0)
 154                 return err;
 155
 156         err = regmap_write(data->regmap, attr->index, val);
 157         return err ? : count;
 158 }
 159
 160 static ssize_t pwm_enable_show(struct device *dev,
 161                                struct device_attribute *attr, char *buf)
 162 {
 163         struct nct7802_data *data = dev_get_drvdata(dev);
 164         struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
 165         unsigned int reg, enabled;
 166         int ret;
 167
 168         ret = regmap_read(data->regmap, REG_SMARTFAN_EN(sattr->index), &reg);
 169         if (ret < 0)
 170                 return ret;
 171         enabled = reg >> SMARTFAN_EN_SHIFT(sattr->index) & 1;
 172         return sprintf(buf, "%u\n", enabled + 1);
 173 }
 174
 175 static ssize_t pwm_enable_store(struct device *dev,
 176                                 struct device_attribute *attr,
 177                                 const char *buf, size_t count)
 178 {
 179         struct nct7802_data *data = dev_get_drvdata(dev);
 180         struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
 181         u8 val;
 182         int ret;
 183
 184         ret = kstrtou8(buf, 0, &val);
 185         if (ret < 0)
 186                 return ret;
 187         if (val < 1 || val > 2)
 188                 return -EINVAL;
 189         ret = regmap_update_bits(data->regmap, REG_SMARTFAN_EN(sattr->index),
 190                                  1 << SMARTFAN_EN_SHIFT(sattr->index),
 191                                  (val - 1) << SMARTFAN_EN_SHIFT(sattr->index));
 192         return ret ? : count;
 193 }
 194
 195 static int nct7802_read_temp(struct nct7802_data *data,
 196                              u8 reg_temp, u8 reg_temp_low, int *temp)
 197 {
 198         unsigned int t1, t2 = 0;
 199         int err;
 200
 201         *temp = 0;
 202
 203         mutex_lock(&data->access_lock);
 204         err = regmap_read(data->regmap, reg_temp, &t1);
 205         if (err < 0)
 206                 goto abort;
 207         t1 <<= 8;
 208         if (reg_temp_low) {     /* 11 bit data */
 209                 err = regmap_read(data->regmap, reg_temp_low, &t2);
 210                 if (err < 0)
 211                         goto abort;
 212         }
 213         t1 |= t2 & 0xe0;
 214         *temp = (s16)t1 / 32 * 125;
 215 abort:
 216         mutex_unlock(&data->access_lock);
 217         return err;
 218 }
 219
 220 static int nct7802_read_fan(struct nct7802_data *data, u8 reg_fan)
 221 {
 222         unsigned int f1, f2;
 223         int ret;
 224
 225         mutex_lock(&data->access_lock);
 226         ret = regmap_read(data->regmap, reg_fan, &f1);
 227         if (ret < 0)
 228                 goto abort;
 229         ret = regmap_read(data->regmap, REG_FANCOUNT_LOW, &f2);
 230         if (ret < 0)
 231                 goto abort;
 232         ret = (f1 << 5) | (f2 >> 3);
 233         /* convert fan count to rpm */
 234         if (ret == 0x1fff)      /* maximum value, assume fan is stopped */
 235                 ret = 0;
 236         else if (ret)
 237                 ret = DIV_ROUND_CLOSEST(1350000U, ret);
 238 abort:
 239         mutex_unlock(&data->access_lock);
 240         return ret;
 241 }
 242
 243 static int nct7802_read_fan_min(struct nct7802_data *data, u8 reg_fan_low,
 244                                 u8 reg_fan_high)
 245 {
 246         unsigned int f1, f2;
 247         int ret;
 248
 249         mutex_lock(&data->access_lock);
 250         ret = regmap_read(data->regmap, reg_fan_low, &f1);
 251         if (ret < 0)
 252                 goto abort;
 253         ret = regmap_read(data->regmap, reg_fan_high, &f2);
 254         if (ret < 0)
 255                 goto abort;
 256         ret = f1 | ((f2 & 0xf8) << 5);
 257         /* convert fan count to rpm */
 258         if (ret == 0x1fff)      /* maximum value, assume no limit */
 259                 ret = 0;
 260         else if (ret)
 261                 ret = DIV_ROUND_CLOSEST(1350000U, ret);
 262         else
 263                 ret = 1350000U;
 264 abort:
 265         mutex_unlock(&data->access_lock);
 266         return ret;
 267 }
 268
 269 static int nct7802_write_fan_min(struct nct7802_data *data, u8 reg_fan_low,
 270                                  u8 reg_fan_high, unsigned long limit)
 271 {
 272         int err;
 273
 274         if (limit)
 275                 limit = DIV_ROUND_CLOSEST(1350000U, limit);
 276         else
 277                 limit = 0x1fff;
 278         limit = clamp_val(limit, 0, 0x1fff);
 279
 280         mutex_lock(&data->access_lock);
 281         err = regmap_write(data->regmap, reg_fan_low, limit & 0xff);
 282         if (err < 0)
 283                 goto abort;
 284
 285         err = regmap_write(data->regmap, reg_fan_high, (limit & 0x1f00) >> 5);
 286 abort:
 287         mutex_unlock(&data->access_lock);
 288         return err;
 289 }
 290
 291 static u8 nct7802_vmul[] = { 4, 2, 2, 2, 2 };
 292
 293 static int nct7802_read_voltage(struct nct7802_data *data, int nr, int index)
 294 {
 295         unsigned int v1, v2;
 296         int ret;
 297
 298         mutex_lock(&data->access_lock);
 299         if (index == 0) {       /* voltage */
 300                 ret = regmap_read(data->regmap, REG_VOLTAGE[nr], &v1);
 301                 if (ret < 0)
 302                         goto abort;
 303                 ret = regmap_read(data->regmap, REG_VOLTAGE_LOW, &v2);
 304                 if (ret < 0)
 305                         goto abort;
 306                 ret = ((v1 << 2) | (v2 >> 6)) * nct7802_vmul[nr];
 307         }  else {       /* limit */
 308                 int shift = 8 - REG_VOLTAGE_LIMIT_MSB_SHIFT[index - 1][nr];
 309
 310                 ret = regmap_read(data->regmap,
 311                                   REG_VOLTAGE_LIMIT_LSB[index - 1][nr], &v1);
 312                 if (ret < 0)
 313                         goto abort;
 314                 ret = regmap_read(data->regmap, REG_VOLTAGE_LIMIT_MSB[nr],
 315                                   &v2);
 316                 if (ret < 0)
 317                         goto abort;
 318                 ret = (v1 | ((v2 << shift) & 0x300)) * nct7802_vmul[nr];
 319         }
 320 abort:
 321         mutex_unlock(&data->access_lock);
 322         return ret;
 323 }
 324
 325 static int nct7802_write_voltage(struct nct7802_data *data, int nr, int index,
 326                                  unsigned long voltage)
 327 {
 328         int shift = 8 - REG_VOLTAGE_LIMIT_MSB_SHIFT[index - 1][nr];
 329         int err;
 330
 331         voltage = clamp_val(voltage, 0, 0x3ff * nct7802_vmul[nr]);
 332         voltage = DIV_ROUND_CLOSEST(voltage, nct7802_vmul[nr]);
 333
 334         mutex_lock(&data->access_lock);
 335         err = regmap_write(data->regmap,
 336                            REG_VOLTAGE_LIMIT_LSB[index - 1][nr],
 337                            voltage & 0xff);
 338         if (err < 0)
 339                 goto abort;
 340
 341         err = regmap_update_bits(data->regmap, REG_VOLTAGE_LIMIT_MSB[nr],
 342                                  0x0300 >> shift, (voltage & 0x0300) >> shift);
 343 abort:
 344         mutex_unlock(&data->access_lock);
 345         return err;
 346 }
 347
 348 static ssize_t in_show(struct device *dev, struct device_attribute *attr,
 349                        char *buf)
 350 {
 351         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 352         struct nct7802_data *data = dev_get_drvdata(dev);
 353         int voltage;
 354
 355         voltage = nct7802_read_voltage(data, sattr->nr, sattr->index);
 356         if (voltage < 0)
 357                 return voltage;
 358
 359         return sprintf(buf, "%d\n", voltage);
 360 }
 361
 362 static ssize_t in_store(struct device *dev, struct device_attribute *attr,
 363                         const char *buf, size_t count)
 364 {
 365         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 366         struct nct7802_data *data = dev_get_drvdata(dev);
 367         int index = sattr->index;
 368         int nr = sattr->nr;
 369         unsigned long val;
 370         int err;
 371
 372         err = kstrtoul(buf, 10, &val);
 373         if (err < 0)
 374                 return err;
 375
 376         err = nct7802_write_voltage(data, nr, index, val);
 377         return err ? : count;
 378 }
 379
 380 static ssize_t temp_show(struct device *dev, struct device_attribute *attr,
 381                          char *buf)
 382 {
 383         struct nct7802_data *data = dev_get_drvdata(dev);
 384         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 385         int err, temp;
 386
 387         err = nct7802_read_temp(data, sattr->nr, sattr->index, &temp);
 388         if (err < 0)
 389                 return err;
 390
 391         return sprintf(buf, "%d\n", temp);
 392 }
 393
 394 static ssize_t temp_store(struct device *dev, struct device_attribute *attr,
 395                           const char *buf, size_t count)
 396 {
 397         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 398         struct nct7802_data *data = dev_get_drvdata(dev);
 399         int nr = sattr->nr;
 400         long val;
 401         int err;
 402
 403         err = kstrtol(buf, 10, &val);
 404         if (err < 0)
 405                 return err;
 406
 407         val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
 408
 409         err = regmap_write(data->regmap, nr, val & 0xff);
 410         return err ? : count;
 411 }
 412
 413 static ssize_t fan_show(struct device *dev, struct device_attribute *attr,
 414                         char *buf)
 415 {
 416         struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
 417         struct nct7802_data *data = dev_get_drvdata(dev);
 418         int speed;
 419
 420         speed = nct7802_read_fan(data, sattr->index);
 421         if (speed < 0)
 422                 return speed;
 423
 424         return sprintf(buf, "%d\n", speed);
 425 }
 426
 427 static ssize_t fan_min_show(struct device *dev, struct device_attribute *attr,
 428                             char *buf)
 429 {
 430         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 431         struct nct7802_data *data = dev_get_drvdata(dev);
 432         int speed;
 433
 434         speed = nct7802_read_fan_min(data, sattr->nr, sattr->index);
 435         if (speed < 0)
 436                 return speed;
 437
 438         return sprintf(buf, "%d\n", speed);
 439 }
 440
 441 static ssize_t fan_min_store(struct device *dev,
 442                              struct device_attribute *attr, const char *buf,
 443                              size_t count)
 444 {
 445         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 446         struct nct7802_data *data = dev_get_drvdata(dev);
 447         unsigned long val;
 448         int err;
 449
 450         err = kstrtoul(buf, 10, &val);
 451         if (err < 0)
 452                 return err;
 453
 454         err = nct7802_write_fan_min(data, sattr->nr, sattr->index, val);
 455         return err ? : count;
 456 }
 457
 458 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
 459                           char *buf)
 460 {
 461         struct nct7802_data *data = dev_get_drvdata(dev);
 462         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 463         int bit = sattr->index;
 464         unsigned int val;
 465         int ret;
 466
 467         ret = regmap_read(data->regmap, sattr->nr, &val);
 468         if (ret < 0)
 469                 return ret;
 470
 471         return sprintf(buf, "%u\n", !!(val & (1 << bit)));
 472 }
 473
 474 static ssize_t
 475 beep_show(struct device *dev, struct device_attribute *attr, char *buf)
 476 {
 477         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 478         struct nct7802_data *data = dev_get_drvdata(dev);
 479         unsigned int regval;
 480         int err;
 481
 482         err = regmap_read(data->regmap, sattr->nr, &regval);
 483         if (err)
 484                 return err;
 485
 486         return sprintf(buf, "%u\n", !!(regval & (1 << sattr->index)));
 487 }
 488
 489 static ssize_t
 490 beep_store(struct device *dev, struct device_attribute *attr, const char *buf,
 491            size_t count)
 492 {
 493         struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
 494         struct nct7802_data *data = dev_get_drvdata(dev);
 495         unsigned long val;
 496         int err;
 497
 498         err = kstrtoul(buf, 10, &val);
 499         if (err < 0)
 500                 return err;
 501         if (val > 1)
 502                 return -EINVAL;
 503
 504         err = regmap_update_bits(data->regmap, sattr->nr, 1 << sattr->index,
 505                                  val ? 1 << sattr->index : 0);
 506         return err ? : count;
 507 }
 508
 509 static SENSOR_DEVICE_ATTR_RW(temp1_type, temp_type, 0);
 510 static SENSOR_DEVICE_ATTR_2_RO(temp1_input, temp, 0x01, REG_TEMP_LSB);
 511 static SENSOR_DEVICE_ATTR_2_RW(temp1_min, temp, 0x31, 0);
 512 static SENSOR_DEVICE_ATTR_2_RW(temp1_max, temp, 0x30, 0);
 513 static SENSOR_DEVICE_ATTR_2_RW(temp1_crit, temp, 0x3a, 0);
 514
 515 static SENSOR_DEVICE_ATTR_RW(temp2_type, temp_type, 1);
 516 static SENSOR_DEVICE_ATTR_2_RO(temp2_input, temp, 0x02, REG_TEMP_LSB);
 517 static SENSOR_DEVICE_ATTR_2_RW(temp2_min, temp, 0x33, 0);
 518 static SENSOR_DEVICE_ATTR_2_RW(temp2_max, temp, 0x32, 0);
 519 static SENSOR_DEVICE_ATTR_2_RW(temp2_crit, temp, 0x3b, 0);
 520
 521 static SENSOR_DEVICE_ATTR_RW(temp3_type, temp_type, 2);
 522 static SENSOR_DEVICE_ATTR_2_RO(temp3_input, temp, 0x03, REG_TEMP_LSB);
 523 static SENSOR_DEVICE_ATTR_2_RW(temp3_min, temp, 0x35, 0);
 524 static SENSOR_DEVICE_ATTR_2_RW(temp3_max, temp, 0x34, 0);
 525 static SENSOR_DEVICE_ATTR_2_RW(temp3_crit, temp, 0x3c, 0);
 526
 527 static SENSOR_DEVICE_ATTR_2_RO(temp4_input, temp, 0x04, 0);
 528 static SENSOR_DEVICE_ATTR_2_RW(temp4_min, temp, 0x37, 0);
 529 static SENSOR_DEVICE_ATTR_2_RW(temp4_max, temp, 0x36, 0);
 530 static SENSOR_DEVICE_ATTR_2_RW(temp4_crit, temp, 0x3d, 0);
 531
 532 static SENSOR_DEVICE_ATTR_2_RO(temp5_input, temp, 0x06, REG_TEMP_PECI_LSB);
 533 static SENSOR_DEVICE_ATTR_2_RW(temp5_min, temp, 0x39, 0);
 534 static SENSOR_DEVICE_ATTR_2_RW(temp5_max, temp, 0x38, 0);
 535 static SENSOR_DEVICE_ATTR_2_RW(temp5_crit, temp, 0x3e, 0);
 536
 537 static SENSOR_DEVICE_ATTR_2_RO(temp6_input, temp, 0x07, REG_TEMP_PECI_LSB);
 538
 539 static SENSOR_DEVICE_ATTR_2_RO(temp1_min_alarm, alarm, 0x18, 0);
 540 static SENSOR_DEVICE_ATTR_2_RO(temp2_min_alarm, alarm, 0x18, 1);
 541 static SENSOR_DEVICE_ATTR_2_RO(temp3_min_alarm, alarm, 0x18, 2);
 542 static SENSOR_DEVICE_ATTR_2_RO(temp4_min_alarm, alarm, 0x18, 3);
 543 static SENSOR_DEVICE_ATTR_2_RO(temp5_min_alarm, alarm, 0x18, 4);
 544
 545 static SENSOR_DEVICE_ATTR_2_RO(temp1_max_alarm, alarm, 0x19, 0);
 546 static SENSOR_DEVICE_ATTR_2_RO(temp2_max_alarm, alarm, 0x19, 1);
 547 static SENSOR_DEVICE_ATTR_2_RO(temp3_max_alarm, alarm, 0x19, 2);
 548 static SENSOR_DEVICE_ATTR_2_RO(temp4_max_alarm, alarm, 0x19, 3);
 549 static SENSOR_DEVICE_ATTR_2_RO(temp5_max_alarm, alarm, 0x19, 4);
 550
 551 static SENSOR_DEVICE_ATTR_2_RO(temp1_crit_alarm, alarm, 0x1b, 0);
 552 static SENSOR_DEVICE_ATTR_2_RO(temp2_crit_alarm, alarm, 0x1b, 1);
 553 static SENSOR_DEVICE_ATTR_2_RO(temp3_crit_alarm, alarm, 0x1b, 2);
 554 static SENSOR_DEVICE_ATTR_2_RO(temp4_crit_alarm, alarm, 0x1b, 3);
 555 static SENSOR_DEVICE_ATTR_2_RO(temp5_crit_alarm, alarm, 0x1b, 4);
 556
 557 static SENSOR_DEVICE_ATTR_2_RO(temp1_fault, alarm, 0x17, 0);
 558 static SENSOR_DEVICE_ATTR_2_RO(temp2_fault, alarm, 0x17, 1);
 559 static SENSOR_DEVICE_ATTR_2_RO(temp3_fault, alarm, 0x17, 2);
 560
 561 static SENSOR_DEVICE_ATTR_2_RW(temp1_beep, beep, 0x5c, 0);
 562 static SENSOR_DEVICE_ATTR_2_RW(temp2_beep, beep, 0x5c, 1);
 563 static SENSOR_DEVICE_ATTR_2_RW(temp3_beep, beep, 0x5c, 2);
 564 static SENSOR_DEVICE_ATTR_2_RW(temp4_beep, beep, 0x5c, 3);
 565 static SENSOR_DEVICE_ATTR_2_RW(temp5_beep, beep, 0x5c, 4);
 566 static SENSOR_DEVICE_ATTR_2_RW(temp6_beep, beep, 0x5c, 5);
 567
 568 static struct attribute *nct7802_temp_attrs[] = {
 569         &sensor_dev_attr_temp1_type.dev_attr.attr,
 570         &sensor_dev_attr_temp1_input.dev_attr.attr,
 571         &sensor_dev_attr_temp1_min.dev_attr.attr,
 572         &sensor_dev_attr_temp1_max.dev_attr.attr,
 573         &sensor_dev_attr_temp1_crit.dev_attr.attr,
 574         &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
 575         &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 576         &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
 577         &sensor_dev_attr_temp1_fault.dev_attr.attr,
 578         &sensor_dev_attr_temp1_beep.dev_attr.attr,
 579
 580         &sensor_dev_attr_temp2_type.dev_attr.attr,              /* 10 */
 581         &sensor_dev_attr_temp2_input.dev_attr.attr,
 582         &sensor_dev_attr_temp2_min.dev_attr.attr,
 583         &sensor_dev_attr_temp2_max.dev_attr.attr,
 584         &sensor_dev_attr_temp2_crit.dev_attr.attr,
 585         &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 586         &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 587         &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 588         &sensor_dev_attr_temp2_fault.dev_attr.attr,
 589         &sensor_dev_attr_temp2_beep.dev_attr.attr,
 590
 591         &sensor_dev_attr_temp3_type.dev_attr.attr,              /* 20 */
 592         &sensor_dev_attr_temp3_input.dev_attr.attr,
 593         &sensor_dev_attr_temp3_min.dev_attr.attr,
 594         &sensor_dev_attr_temp3_max.dev_attr.attr,
 595         &sensor_dev_attr_temp3_crit.dev_attr.attr,
 596         &sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
 597         &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 598         &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
 599         &sensor_dev_attr_temp3_fault.dev_attr.attr,
 600         &sensor_dev_attr_temp3_beep.dev_attr.attr,
 601
 602         &sensor_dev_attr_temp4_input.dev_attr.attr,             /* 30 */
 603         &sensor_dev_attr_temp4_min.dev_attr.attr,
 604         &sensor_dev_attr_temp4_max.dev_attr.attr,
 605         &sensor_dev_attr_temp4_crit.dev_attr.attr,
 606         &sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
 607         &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
 608         &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
 609         &sensor_dev_attr_temp4_beep.dev_attr.attr,
 610
 611         &sensor_dev_attr_temp5_input.dev_attr.attr,             /* 38 */
 612         &sensor_dev_attr_temp5_min.dev_attr.attr,
 613         &sensor_dev_attr_temp5_max.dev_attr.attr,
 614         &sensor_dev_attr_temp5_crit.dev_attr.attr,
 615         &sensor_dev_attr_temp5_min_alarm.dev_attr.attr,
 616         &sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
 617         &sensor_dev_attr_temp5_crit_alarm.dev_attr.attr,
 618         &sensor_dev_attr_temp5_beep.dev_attr.attr,
 619
 620         &sensor_dev_attr_temp6_input.dev_attr.attr,             /* 46 */
 621         &sensor_dev_attr_temp6_beep.dev_attr.attr,
 622
 623         NULL
 624 };
 625
 626 static umode_t nct7802_temp_is_visible(struct kobject *kobj,
 627                                        struct attribute *attr, int index)
 628 {
 629         struct device *dev = container_of(kobj, struct device, kobj);
 630         struct nct7802_data *data = dev_get_drvdata(dev);
 631         unsigned int reg;
 632         int err;
 633
 634         err = regmap_read(data->regmap, REG_MODE, &reg);
 635         if (err < 0)
 636                 return 0;
 637
 638         if (index < 10 &&
 639             (reg & 03) != 0x01 && (reg & 0x03) != 0x02)         /* RD1 */
 640                 return 0;
 641
 642         if (index >= 10 && index < 20 &&
 643             (reg & 0x0c) != 0x04 && (reg & 0x0c) != 0x08)       /* RD2 */
 644                 return 0;
 645         if (index >= 20 && index < 30 && (reg & 0x30) != 0x20)  /* RD3 */
 646                 return 0;
 647
 648         if (index >= 30 && index < 38)                          /* local */
 649                 return attr->mode;
 650
 651         err = regmap_read(data->regmap, REG_PECI_ENABLE, &reg);
 652         if (err < 0)
 653                 return 0;
 654
 655         if (index >= 38 && index < 46 && !(reg & 0x01))         /* PECI 0 */
 656                 return 0;
 657
 658         if (index >= 0x46 && (!(reg & 0x02)))                   /* PECI 1 */
 659                 return 0;
 660
 661         return attr->mode;
 662 }
 663
 664 static const struct attribute_group nct7802_temp_group = {
 665         .attrs = nct7802_temp_attrs,
 666         .is_visible = nct7802_temp_is_visible,
 667 };
 668
 669 static SENSOR_DEVICE_ATTR_2_RO(in0_input, in, 0, 0);
 670 static SENSOR_DEVICE_ATTR_2_RW(in0_min, in, 0, 1);
 671 static SENSOR_DEVICE_ATTR_2_RW(in0_max, in, 0, 2);
 672 static SENSOR_DEVICE_ATTR_2_RO(in0_alarm, alarm, 0x1e, 3);
 673 static SENSOR_DEVICE_ATTR_2_RW(in0_beep, beep, 0x5a, 3);
 674
 675 static SENSOR_DEVICE_ATTR_2_RO(in1_input, in, 1, 0);
 676
 677 static SENSOR_DEVICE_ATTR_2_RO(in2_input, in, 2, 0);
 678 static SENSOR_DEVICE_ATTR_2_RW(in2_min, in, 2, 1);
 679 static SENSOR_DEVICE_ATTR_2_RW(in2_max, in, 2, 2);
 680 static SENSOR_DEVICE_ATTR_2_RO(in2_alarm, alarm, 0x1e, 0);
 681 static SENSOR_DEVICE_ATTR_2_RW(in2_beep, beep, 0x5a, 0);
 682
 683 static SENSOR_DEVICE_ATTR_2_RO(in3_input, in, 3, 0);
 684 static SENSOR_DEVICE_ATTR_2_RW(in3_min, in, 3, 1);
 685 static SENSOR_DEVICE_ATTR_2_RW(in3_max, in, 3, 2);
 686 static SENSOR_DEVICE_ATTR_2_RO(in3_alarm, alarm, 0x1e, 1);
 687 static SENSOR_DEVICE_ATTR_2_RW(in3_beep, beep, 0x5a, 1);
 688
 689 static SENSOR_DEVICE_ATTR_2_RO(in4_input, in, 4, 0);
 690 static SENSOR_DEVICE_ATTR_2_RW(in4_min, in, 4, 1);
 691 static SENSOR_DEVICE_ATTR_2_RW(in4_max, in, 4, 2);
 692 static SENSOR_DEVICE_ATTR_2_RO(in4_alarm, alarm, 0x1e, 2);
 693 static SENSOR_DEVICE_ATTR_2_RW(in4_beep, beep, 0x5a, 2);
 694
 695 static struct attribute *nct7802_in_attrs[] = {
 696         &sensor_dev_attr_in0_input.dev_attr.attr,
 697         &sensor_dev_attr_in0_min.dev_attr.attr,
 698         &sensor_dev_attr_in0_max.dev_attr.attr,
 699         &sensor_dev_attr_in0_alarm.dev_attr.attr,
 700         &sensor_dev_attr_in0_beep.dev_attr.attr,
 701
 702         &sensor_dev_attr_in1_input.dev_attr.attr,       /* 5 */
 703
 704         &sensor_dev_attr_in2_input.dev_attr.attr,       /* 6 */
 705         &sensor_dev_attr_in2_min.dev_attr.attr,
 706         &sensor_dev_attr_in2_max.dev_attr.attr,
 707         &sensor_dev_attr_in2_alarm.dev_attr.attr,
 708         &sensor_dev_attr_in2_beep.dev_attr.attr,
 709
 710         &sensor_dev_attr_in3_input.dev_attr.attr,       /* 11 */
 711         &sensor_dev_attr_in3_min.dev_attr.attr,
 712         &sensor_dev_attr_in3_max.dev_attr.attr,
 713         &sensor_dev_attr_in3_alarm.dev_attr.attr,
 714         &sensor_dev_attr_in3_beep.dev_attr.attr,
 715
 716         &sensor_dev_attr_in4_input.dev_attr.attr,       /* 17 */
 717         &sensor_dev_attr_in4_min.dev_attr.attr,
 718         &sensor_dev_attr_in4_max.dev_attr.attr,
 719         &sensor_dev_attr_in4_alarm.dev_attr.attr,
 720         &sensor_dev_attr_in4_beep.dev_attr.attr,
 721
 722         NULL,
 723 };
 724
 725 static umode_t nct7802_in_is_visible(struct kobject *kobj,
 726                                      struct attribute *attr, int index)
 727 {
 728         struct device *dev = container_of(kobj, struct device, kobj);
 729         struct nct7802_data *data = dev_get_drvdata(dev);
 730         unsigned int reg;
 731         int err;
 732
 733         if (index < 6)                                          /* VCC, VCORE */
 734                 return attr->mode;
 735
 736         err = regmap_read(data->regmap, REG_MODE, &reg);
 737         if (err < 0)
 738                 return 0;
 739
 740         if (index >= 6 && index < 11 && (reg & 0x03) != 0x03)   /* VSEN1 */
 741                 return 0;
 742         if (index >= 11 && index < 17 && (reg & 0x0c) != 0x0c)  /* VSEN2 */
 743                 return 0;
 744         if (index >= 17 && (reg & 0x30) != 0x30)                /* VSEN3 */
 745                 return 0;
 746
 747         return attr->mode;
 748 }
 749
 750 static const struct attribute_group nct7802_in_group = {
 751         .attrs = nct7802_in_attrs,
 752         .is_visible = nct7802_in_is_visible,
 753 };
 754
 755 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0x10);
 756 static SENSOR_DEVICE_ATTR_2_RW(fan1_min, fan_min, 0x49, 0x4c);
 757 static SENSOR_DEVICE_ATTR_2_RO(fan1_alarm, alarm, 0x1a, 0);
 758 static SENSOR_DEVICE_ATTR_2_RW(fan1_beep, beep, 0x5b, 0);
 759 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 0x11);
 760 static SENSOR_DEVICE_ATTR_2_RW(fan2_min, fan_min, 0x4a, 0x4d);
 761 static SENSOR_DEVICE_ATTR_2_RO(fan2_alarm, alarm, 0x1a, 1);
 762 static SENSOR_DEVICE_ATTR_2_RW(fan2_beep, beep, 0x5b, 1);
 763 static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 0x12);
 764 static SENSOR_DEVICE_ATTR_2_RW(fan3_min, fan_min, 0x4b, 0x4e);
 765 static SENSOR_DEVICE_ATTR_2_RO(fan3_alarm, alarm, 0x1a, 2);
 766 static SENSOR_DEVICE_ATTR_2_RW(fan3_beep, beep, 0x5b, 2);
 767
 768 /* 7.2.89 Fan Control Output Type */
 769 static SENSOR_DEVICE_ATTR_RO(pwm1_mode, pwm_mode, 0);
 770 static SENSOR_DEVICE_ATTR_RO(pwm2_mode, pwm_mode, 1);
 771 static SENSOR_DEVICE_ATTR_RO(pwm3_mode, pwm_mode, 2);
 772
 773 /* 7.2.91... Fan Control Output Value */
 774 static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, REG_PWM(0));
 775 static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, REG_PWM(1));
 776 static SENSOR_DEVICE_ATTR_RW(pwm3, pwm, REG_PWM(2));
 777
 778 /* 7.2.95... Temperature to Fan mapping Relationships Register */
 779 static SENSOR_DEVICE_ATTR_RW(pwm1_enable, pwm_enable, 0);
 780 static SENSOR_DEVICE_ATTR_RW(pwm2_enable, pwm_enable, 1);
 781 static SENSOR_DEVICE_ATTR_RW(pwm3_enable, pwm_enable, 2);
 782
 783 static struct attribute *nct7802_fan_attrs[] = {
 784         &sensor_dev_attr_fan1_input.dev_attr.attr,
 785         &sensor_dev_attr_fan1_min.dev_attr.attr,
 786         &sensor_dev_attr_fan1_alarm.dev_attr.attr,
 787         &sensor_dev_attr_fan1_beep.dev_attr.attr,
 788         &sensor_dev_attr_fan2_input.dev_attr.attr,
 789         &sensor_dev_attr_fan2_min.dev_attr.attr,
 790         &sensor_dev_attr_fan2_alarm.dev_attr.attr,
 791         &sensor_dev_attr_fan2_beep.dev_attr.attr,
 792         &sensor_dev_attr_fan3_input.dev_attr.attr,
 793         &sensor_dev_attr_fan3_min.dev_attr.attr,
 794         &sensor_dev_attr_fan3_alarm.dev_attr.attr,
 795         &sensor_dev_attr_fan3_beep.dev_attr.attr,
 796
 797         NULL
 798 };
 799
 800 static umode_t nct7802_fan_is_visible(struct kobject *kobj,
 801                                       struct attribute *attr, int index)
 802 {
 803         struct device *dev = container_of(kobj, struct device, kobj);
 804         struct nct7802_data *data = dev_get_drvdata(dev);
 805         int fan = index / 4;    /* 4 attributes per fan */
 806         unsigned int reg;
 807         int err;
 808
 809         err = regmap_read(data->regmap, REG_FAN_ENABLE, &reg);
 810         if (err < 0 || !(reg & (1 << fan)))
 811                 return 0;
 812
 813         return attr->mode;
 814 }
 815
 816 static const struct attribute_group nct7802_fan_group = {
 817         .attrs = nct7802_fan_attrs,
 818         .is_visible = nct7802_fan_is_visible,
 819 };
 820
 821 static struct attribute *nct7802_pwm_attrs[] = {
 822         &sensor_dev_attr_pwm1_enable.dev_attr.attr,
 823         &sensor_dev_attr_pwm1_mode.dev_attr.attr,
 824         &sensor_dev_attr_pwm1.dev_attr.attr,
 825         &sensor_dev_attr_pwm2_enable.dev_attr.attr,
 826         &sensor_dev_attr_pwm2_mode.dev_attr.attr,
 827         &sensor_dev_attr_pwm2.dev_attr.attr,
 828         &sensor_dev_attr_pwm3_enable.dev_attr.attr,
 829         &sensor_dev_attr_pwm3_mode.dev_attr.attr,
 830         &sensor_dev_attr_pwm3.dev_attr.attr,
 831         NULL
 832 };
 833
 834 static const struct attribute_group nct7802_pwm_group = {
 835         .attrs = nct7802_pwm_attrs,
 836 };
 837
 838 /* 7.2.115... 0x80-0x83, 0x84 Temperature (X-axis) transition */
 839 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point1_temp, temp, 0x80, 0);
 840 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point2_temp, temp, 0x81, 0);
 841 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point3_temp, temp, 0x82, 0);
 842 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point4_temp, temp, 0x83, 0);
 843 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point5_temp, temp, 0x84, 0);
 844
 845 /* 7.2.120... 0x85-0x88 PWM (Y-axis) transition */
 846 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_pwm, pwm, 0x85);
 847 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_pwm, pwm, 0x86);
 848 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_pwm, pwm, 0x87);
 849 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_pwm, pwm, 0x88);
 850 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point5_pwm, pwm, 0);
 851
 852 /* 7.2.124 Table 2 X-axis Transition Point 1 Register */
 853 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point1_temp, temp, 0x90, 0);
 854 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point2_temp, temp, 0x91, 0);
 855 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point3_temp, temp, 0x92, 0);
 856 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point4_temp, temp, 0x93, 0);
 857 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point5_temp, temp, 0x94, 0);
 858
 859 /* 7.2.129 Table 2 Y-axis Transition Point 1 Register */
 860 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point1_pwm, pwm, 0x95);
 861 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point2_pwm, pwm, 0x96);
 862 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point3_pwm, pwm, 0x97);
 863 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point4_pwm, pwm, 0x98);
 864 static SENSOR_DEVICE_ATTR_RO(pwm2_auto_point5_pwm, pwm, 0);
 865
 866 /* 7.2.133 Table 3 X-axis Transition Point 1 Register */
 867 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point1_temp, temp, 0xA0, 0);
 868 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point2_temp, temp, 0xA1, 0);
 869 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point3_temp, temp, 0xA2, 0);
 870 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point4_temp, temp, 0xA3, 0);
 871 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point5_temp, temp, 0xA4, 0);
 872
 873 /* 7.2.138 Table 3 Y-axis Transition Point 1 Register */
 874 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point1_pwm, pwm, 0xA5);
 875 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point2_pwm, pwm, 0xA6);
 876 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point3_pwm, pwm, 0xA7);
 877 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point4_pwm, pwm, 0xA8);
 878 static SENSOR_DEVICE_ATTR_RO(pwm3_auto_point5_pwm, pwm, 0);
 879
 880 static struct attribute *nct7802_auto_point_attrs[] = {
 881         &sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr,
 882         &sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr,
 883         &sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr,
 884         &sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr,
 885         &sensor_dev_attr_pwm1_auto_point5_temp.dev_attr.attr,
 886
 887         &sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
 888         &sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
 889         &sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
 890         &sensor_dev_attr_pwm1_auto_point4_pwm.dev_attr.attr,
 891         &sensor_dev_attr_pwm1_auto_point5_pwm.dev_attr.attr,
 892
 893         &sensor_dev_attr_pwm2_auto_point1_temp.dev_attr.attr,
 894         &sensor_dev_attr_pwm2_auto_point2_temp.dev_attr.attr,
 895         &sensor_dev_attr_pwm2_auto_point3_temp.dev_attr.attr,
 896         &sensor_dev_attr_pwm2_auto_point4_temp.dev_attr.attr,
 897         &sensor_dev_attr_pwm2_auto_point5_temp.dev_attr.attr,
 898
 899         &sensor_dev_attr_pwm2_auto_point1_pwm.dev_attr.attr,
 900         &sensor_dev_attr_pwm2_auto_point2_pwm.dev_attr.attr,
 901         &sensor_dev_attr_pwm2_auto_point3_pwm.dev_attr.attr,
 902         &sensor_dev_attr_pwm2_auto_point4_pwm.dev_attr.attr,
 903         &sensor_dev_attr_pwm2_auto_point5_pwm.dev_attr.attr,
 904
 905         &sensor_dev_attr_pwm3_auto_point1_temp.dev_attr.attr,
 906         &sensor_dev_attr_pwm3_auto_point2_temp.dev_attr.attr,
 907         &sensor_dev_attr_pwm3_auto_point3_temp.dev_attr.attr,
 908         &sensor_dev_attr_pwm3_auto_point4_temp.dev_attr.attr,
 909         &sensor_dev_attr_pwm3_auto_point5_temp.dev_attr.attr,
 910
 911         &sensor_dev_attr_pwm3_auto_point1_pwm.dev_attr.attr,
 912         &sensor_dev_attr_pwm3_auto_point2_pwm.dev_attr.attr,
 913         &sensor_dev_attr_pwm3_auto_point3_pwm.dev_attr.attr,
 914         &sensor_dev_attr_pwm3_auto_point4_pwm.dev_attr.attr,
 915         &sensor_dev_attr_pwm3_auto_point5_pwm.dev_attr.attr,
 916
 917         NULL
 918 };
 919
 920 static const struct attribute_group nct7802_auto_point_group = {
 921         .attrs = nct7802_auto_point_attrs,
 922 };
 923
 924 static const struct attribute_group *nct7802_groups[] = {
 925         &nct7802_temp_group,
 926         &nct7802_in_group,
 927         &nct7802_fan_group,
 928         &nct7802_pwm_group,
 929         &nct7802_auto_point_group,
 930         NULL
 931 };
 932
 933 static int nct7802_detect(struct i2c_client *client,
 934                           struct i2c_board_info *info)
 935 {
 936         int reg;
 937
 938         /*
 939          * Chip identification registers are only available in bank 0,
 940          * so only attempt chip detection if bank 0 is selected
 941          */
 942         reg = i2c_smbus_read_byte_data(client, REG_BANK);
 943         if (reg != 0x00)
 944                 return -ENODEV;
 945
 946         reg = i2c_smbus_read_byte_data(client, REG_VENDOR_ID);
 947         if (reg != 0x50)
 948                 return -ENODEV;
 949
 950         reg = i2c_smbus_read_byte_data(client, REG_CHIP_ID);
 951         if (reg != 0xc3)
 952                 return -ENODEV;
 953
 954         reg = i2c_smbus_read_byte_data(client, REG_VERSION_ID);
 955         if (reg < 0 || (reg & 0xf0) != 0x20)
 956                 return -ENODEV;
 957
 958         /* Also validate lower bits of voltage and temperature registers */
 959         reg = i2c_smbus_read_byte_data(client, REG_TEMP_LSB);
 960         if (reg < 0 || (reg & 0x1f))
 961                 return -ENODEV;
 962
 963         reg = i2c_smbus_read_byte_data(client, REG_TEMP_PECI_LSB);
 964         if (reg < 0 || (reg & 0x3f))
 965                 return -ENODEV;
 966
 967         reg = i2c_smbus_read_byte_data(client, REG_VOLTAGE_LOW);
 968         if (reg < 0 || (reg & 0x3f))
 969                 return -ENODEV;
 970
 971         strlcpy(info->type, "nct7802", I2C_NAME_SIZE);
 972         return 0;
 973 }
 974
 975 static bool nct7802_regmap_is_volatile(struct device *dev, unsigned int reg)
 976 {
 977         return (reg != REG_BANK && reg <= 0x20) ||
 978                 (reg >= REG_PWM(0) && reg <= REG_PWM(2));
 979 }
 980
 981 static const struct regmap_config nct7802_regmap_config = {
 982         .reg_bits = 8,
 983         .val_bits = 8,
 984         .cache_type = REGCACHE_RBTREE,
 985         .volatile_reg = nct7802_regmap_is_volatile,
 986 };
 987
 988 static int nct7802_init_chip(struct nct7802_data *data)
 989 {
 990         int err;
 991
 992         /* Enable ADC */
 993         err = regmap_update_bits(data->regmap, REG_START, 0x01, 0x01);
 994         if (err)
 995                 return err;
 996
 997         /* Enable local temperature sensor */
 998         err = regmap_update_bits(data->regmap, REG_MODE, 0x40, 0x40);
 999         if (err)
1000                 return err;
1001
1002         /* Enable Vcore and VCC voltage monitoring */
1003         return regmap_update_bits(data->regmap, REG_VMON_ENABLE, 0x03, 0x03);
1004 }
1005
1006 static int nct7802_probe(struct i2c_client *client,
1007                          const struct i2c_device_id *id)
1008 {
1009         struct device *dev = &client->dev;
1010         struct nct7802_data *data;
1011         struct device *hwmon_dev;
1012         int ret;
1013
1014         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
1015         if (data == NULL)
1016                 return -ENOMEM;
1017
1018         data->regmap = devm_regmap_init_i2c(client, &nct7802_regmap_config);
1019         if (IS_ERR(data->regmap))
1020                 return PTR_ERR(data->regmap);
1021
1022         mutex_init(&data->access_lock);
1023
1024         ret = nct7802_init_chip(data);
1025         if (ret < 0)
1026                 return ret;
1027
1028         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
1029                                                            data,
1030                                                            nct7802_groups);
1031         return PTR_ERR_OR_ZERO(hwmon_dev);
1032 }
1033
1034 static const unsigned short nct7802_address_list[] = {
1035         0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END
1036 };
1037
1038 static const struct i2c_device_id nct7802_idtable[] = {
1039         { "nct7802", 0 },
1040         { }
1041 };
1042 MODULE_DEVICE_TABLE(i2c, nct7802_idtable);
1043
1044 static struct i2c_driver nct7802_driver = {
1045         .class = I2C_CLASS_HWMON,
1046         .driver = {
1047                 .name = DRVNAME,
1048         },
1049         .detect = nct7802_detect,
1050         .probe = nct7802_probe,
1051         .id_table = nct7802_idtable,
1052         .address_list = nct7802_address_list,
1053 };
1054
1055 module_i2c_driver(nct7802_driver);
1056
1057 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
1058 MODULE_DESCRIPTION("NCT7802Y Hardware Monitoring Driver");
1059 MODULE_LICENSE("GPL v2");