drivers/hwmon/adt7411.c

   1 /*
   2  *  Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
   3  *
   4  *  Copyright (C) 2008, 2010 Pengutronix
   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 version 2 as
   8  *  published by the Free Software Foundation.
   9  *
  10  *  TODO: SPI, use power-down mode for suspend?, interrupt handling?
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/err.h>
  17 #include <linux/mutex.h>
  18 #include <linux/jiffies.h>
  19 #include <linux/i2c.h>
  20 #include <linux/hwmon.h>
  21 #include <linux/hwmon-sysfs.h>
  22 #include <linux/slab.h>
  23
  24 #define ADT7411_REG_STAT_1                      0x00
  25 #define ADT7411_STAT_1_INT_TEMP_HIGH            BIT(0)
  26 #define ADT7411_STAT_1_INT_TEMP_LOW             BIT(1)
  27 #define ADT7411_STAT_1_EXT_TEMP_HIGH_AIN1       BIT(2)
  28 #define ADT7411_STAT_1_EXT_TEMP_LOW             BIT(3)
  29 #define ADT7411_STAT_1_EXT_TEMP_FAULT           BIT(4)
  30 #define ADT7411_STAT_1_AIN2                     BIT(5)
  31 #define ADT7411_STAT_1_AIN3                     BIT(6)
  32 #define ADT7411_STAT_1_AIN4                     BIT(7)
  33 #define ADT7411_REG_STAT_2                      0x01
  34 #define ADT7411_STAT_2_AIN5                     BIT(0)
  35 #define ADT7411_STAT_2_AIN6                     BIT(1)
  36 #define ADT7411_STAT_2_AIN7                     BIT(2)
  37 #define ADT7411_STAT_2_AIN8                     BIT(3)
  38 #define ADT7411_STAT_2_VDD                      BIT(4)
  39 #define ADT7411_REG_INT_TEMP_VDD_LSB            0x03
  40 #define ADT7411_REG_EXT_TEMP_AIN14_LSB          0x04
  41 #define ADT7411_REG_VDD_MSB                     0x06
  42 #define ADT7411_REG_INT_TEMP_MSB                0x07
  43 #define ADT7411_REG_EXT_TEMP_AIN1_MSB           0x08
  44
  45 #define ADT7411_REG_CFG1                        0x18
  46 #define ADT7411_CFG1_START_MONITOR              BIT(0)
  47 #define ADT7411_CFG1_RESERVED_BIT1              BIT(1)
  48 #define ADT7411_CFG1_EXT_TDM                    BIT(2)
  49 #define ADT7411_CFG1_RESERVED_BIT3              BIT(3)
  50
  51 #define ADT7411_REG_CFG2                        0x19
  52 #define ADT7411_CFG2_DISABLE_AVG                BIT(5)
  53
  54 #define ADT7411_REG_CFG3                        0x1a
  55 #define ADT7411_CFG3_ADC_CLK_225                BIT(0)
  56 #define ADT7411_CFG3_RESERVED_BIT1              BIT(1)
  57 #define ADT7411_CFG3_RESERVED_BIT2              BIT(2)
  58 #define ADT7411_CFG3_RESERVED_BIT3              BIT(3)
  59 #define ADT7411_CFG3_REF_VDD                    BIT(4)
  60
  61 #define ADT7411_REG_VDD_HIGH                    0x23
  62 #define ADT7411_REG_VDD_LOW                     0x24
  63 #define ADT7411_REG_TEMP_HIGH(nr)               (0x25 + 2 * (nr))
  64 #define ADT7411_REG_TEMP_LOW(nr)                (0x26 + 2 * (nr))
  65 #define ADT7411_REG_IN_HIGH(nr)         ((nr) > 1 \
  66                                                   ? 0x2b + 2 * ((nr)-2) \
  67                                                   : 0x27)
  68 #define ADT7411_REG_IN_LOW(nr)                  ((nr) > 1 \
  69                                                   ? 0x2c + 2 * ((nr)-2) \
  70                                                   : 0x28)
  71
  72 #define ADT7411_REG_DEVICE_ID                   0x4d
  73 #define ADT7411_REG_MANUFACTURER_ID             0x4e
  74
  75 #define ADT7411_DEVICE_ID                       0x2
  76 #define ADT7411_MANUFACTURER_ID                 0x41
  77
  78 static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
  79
  80 static const u8 adt7411_in_alarm_reg[] = {
  81         ADT7411_REG_STAT_2,
  82         ADT7411_REG_STAT_1,
  83         ADT7411_REG_STAT_1,
  84         ADT7411_REG_STAT_1,
  85         ADT7411_REG_STAT_1,
  86         ADT7411_REG_STAT_2,
  87         ADT7411_REG_STAT_2,
  88         ADT7411_REG_STAT_2,
  89         ADT7411_REG_STAT_2,
  90 };
  91
  92 static const u8 adt7411_in_alarm_bits[] = {
  93         ADT7411_STAT_2_VDD,
  94         ADT7411_STAT_1_EXT_TEMP_HIGH_AIN1,
  95         ADT7411_STAT_1_AIN2,
  96         ADT7411_STAT_1_AIN3,
  97         ADT7411_STAT_1_AIN4,
  98         ADT7411_STAT_2_AIN5,
  99         ADT7411_STAT_2_AIN6,
 100         ADT7411_STAT_2_AIN7,
 101         ADT7411_STAT_2_AIN8,
 102 };
 103
 104 struct adt7411_data {
 105         struct mutex device_lock;       /* for "atomic" device accesses */
 106         struct mutex update_lock;
 107         unsigned long next_update;
 108         long vref_cached;
 109         struct i2c_client *client;
 110         bool use_ext_temp;
 111 };
 112
 113 /*
 114  * When reading a register containing (up to 4) lsb, all associated
 115  * msb-registers get locked by the hardware. After _one_ of those msb is read,
 116  * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
 117  * is protected here with a mutex, too.
 118  */
 119 static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
 120                                 u8 msb_reg, u8 lsb_shift)
 121 {
 122         struct adt7411_data *data = i2c_get_clientdata(client);
 123         int val, tmp;
 124
 125         mutex_lock(&data->device_lock);
 126
 127         val = i2c_smbus_read_byte_data(client, lsb_reg);
 128         if (val < 0)
 129                 goto exit_unlock;
 130
 131         tmp = (val >> lsb_shift) & 3;
 132         val = i2c_smbus_read_byte_data(client, msb_reg);
 133
 134         if (val >= 0)
 135                 val = (val << 2) | tmp;
 136
 137  exit_unlock:
 138         mutex_unlock(&data->device_lock);
 139
 140         return val;
 141 }
 142
 143 static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
 144                                 bool flag)
 145 {
 146         struct adt7411_data *data = i2c_get_clientdata(client);
 147         int ret, val;
 148
 149         mutex_lock(&data->device_lock);
 150
 151         ret = i2c_smbus_read_byte_data(client, reg);
 152         if (ret < 0)
 153                 goto exit_unlock;
 154
 155         if (flag)
 156                 val = ret | bit;
 157         else
 158                 val = ret & ~bit;
 159
 160         ret = i2c_smbus_write_byte_data(client, reg, val);
 161
 162  exit_unlock:
 163         mutex_unlock(&data->device_lock);
 164         return ret;
 165 }
 166
 167 static ssize_t adt7411_show_bit(struct device *dev,
 168                                 struct device_attribute *attr, char *buf)
 169 {
 170         struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
 171         struct adt7411_data *data = dev_get_drvdata(dev);
 172         struct i2c_client *client = data->client;
 173         int ret = i2c_smbus_read_byte_data(client, attr2->index);
 174
 175         return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
 176 }
 177
 178 static ssize_t adt7411_set_bit(struct device *dev,
 179                                struct device_attribute *attr, const char *buf,
 180                                size_t count)
 181 {
 182         struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
 183         struct adt7411_data *data = dev_get_drvdata(dev);
 184         struct i2c_client *client = data->client;
 185         int ret;
 186         unsigned long flag;
 187
 188         ret = kstrtoul(buf, 0, &flag);
 189         if (ret || flag > 1)
 190                 return -EINVAL;
 191
 192         ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
 193
 194         /* force update */
 195         mutex_lock(&data->update_lock);
 196         data->next_update = jiffies;
 197         mutex_unlock(&data->update_lock);
 198
 199         return ret < 0 ? ret : count;
 200 }
 201
 202 #define ADT7411_BIT_ATTR(__name, __reg, __bit) \
 203         SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
 204         adt7411_set_bit, __bit, __reg)
 205
 206 static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
 207 static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
 208 static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);
 209
 210 static struct attribute *adt7411_attrs[] = {
 211         &sensor_dev_attr_no_average.dev_attr.attr,
 212         &sensor_dev_attr_fast_sampling.dev_attr.attr,
 213         &sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
 214         NULL
 215 };
 216 ATTRIBUTE_GROUPS(adt7411);
 217
 218 static int adt7411_read_in_alarm(struct device *dev, int channel, long *val)
 219 {
 220         struct adt7411_data *data = dev_get_drvdata(dev);
 221         struct i2c_client *client = data->client;
 222         int ret;
 223
 224         ret = i2c_smbus_read_byte_data(client, adt7411_in_alarm_reg[channel]);
 225         if (ret < 0)
 226                 return ret;
 227         *val = !!(ret & adt7411_in_alarm_bits[channel]);
 228         return 0;
 229 }
 230
 231 static int adt7411_read_in_vdd(struct device *dev, u32 attr, long *val)
 232 {
 233         struct adt7411_data *data = dev_get_drvdata(dev);
 234         struct i2c_client *client = data->client;
 235         int ret;
 236
 237         switch (attr) {
 238         case hwmon_in_input:
 239                 ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
 240                                           ADT7411_REG_VDD_MSB, 2);
 241                 if (ret < 0)
 242                         return ret;
 243                 *val = ret * 7000 / 1024;
 244                 return 0;
 245         case hwmon_in_min:
 246                 ret = i2c_smbus_read_byte_data(client, ADT7411_REG_VDD_LOW);
 247                 if (ret < 0)
 248                         return ret;
 249                 *val = ret * 7000 / 256;
 250                 return 0;
 251         case hwmon_in_max:
 252                 ret = i2c_smbus_read_byte_data(client, ADT7411_REG_VDD_HIGH);
 253                 if (ret < 0)
 254                         return ret;
 255                 *val = ret * 7000 / 256;
 256                 return 0;
 257         case hwmon_in_alarm:
 258                 return adt7411_read_in_alarm(dev, 0, val);
 259         default:
 260                 return -EOPNOTSUPP;
 261         }
 262 }
 263
 264 static int adt7411_update_vref(struct device *dev)
 265 {
 266         struct adt7411_data *data = dev_get_drvdata(dev);
 267         struct i2c_client *client = data->client;
 268         int val;
 269
 270         if (time_after_eq(jiffies, data->next_update)) {
 271                 val = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
 272                 if (val < 0)
 273                         return val;
 274
 275                 if (val & ADT7411_CFG3_REF_VDD) {
 276                         val = adt7411_read_in_vdd(dev, hwmon_in_input,
 277                                                   &data->vref_cached);
 278                         if (val < 0)
 279                                 return val;
 280                 } else {
 281                         data->vref_cached = 2250;
 282                 }
 283
 284                 data->next_update = jiffies + HZ;
 285         }
 286
 287         return 0;
 288 }
 289
 290 static int adt7411_read_in_chan(struct device *dev, u32 attr, int channel,
 291                                 long *val)
 292 {
 293         struct adt7411_data *data = dev_get_drvdata(dev);
 294         struct i2c_client *client = data->client;
 295
 296         int ret;
 297         int reg, lsb_reg, lsb_shift;
 298         int nr = channel - 1;
 299
 300         mutex_lock(&data->update_lock);
 301         ret = adt7411_update_vref(dev);
 302         if (ret < 0)
 303                 goto exit_unlock;
 304
 305         switch (attr) {
 306         case hwmon_in_input:
 307                 lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
 308                 lsb_shift = 2 * (nr & 0x03);
 309                 ret = adt7411_read_10_bit(client, lsb_reg,
 310                                           ADT7411_REG_EXT_TEMP_AIN1_MSB + nr,
 311                                           lsb_shift);
 312                 if (ret < 0)
 313                         goto exit_unlock;
 314                 *val = ret * data->vref_cached / 1024;
 315                 ret = 0;
 316                 break;
 317         case hwmon_in_min:
 318         case hwmon_in_max:
 319                 reg = (attr == hwmon_in_min)
 320                         ? ADT7411_REG_IN_LOW(channel)
 321                         : ADT7411_REG_IN_HIGH(channel);
 322                 ret = i2c_smbus_read_byte_data(client, reg);
 323                 if (ret < 0)
 324                         goto exit_unlock;
 325                 *val = ret * data->vref_cached / 256;
 326                 ret = 0;
 327                 break;
 328         case hwmon_in_alarm:
 329                 ret = adt7411_read_in_alarm(dev, channel, val);
 330                 break;
 331         default:
 332                 ret = -EOPNOTSUPP;
 333                 break;
 334         }
 335  exit_unlock:
 336         mutex_unlock(&data->update_lock);
 337         return ret;
 338 }
 339
 340 static int adt7411_read_in(struct device *dev, u32 attr, int channel,
 341                            long *val)
 342 {
 343         if (channel == 0)
 344                 return adt7411_read_in_vdd(dev, attr, val);
 345         else
 346                 return adt7411_read_in_chan(dev, attr, channel, val);
 347 }
 348
 349
 350 static int adt7411_read_temp_alarm(struct device *dev, u32 attr, int channel,
 351                                    long *val)
 352 {
 353         struct adt7411_data *data = dev_get_drvdata(dev);
 354         struct i2c_client *client = data->client;
 355         int ret, bit;
 356
 357         ret = i2c_smbus_read_byte_data(client, ADT7411_REG_STAT_1);
 358         if (ret < 0)
 359                 return ret;
 360
 361         switch (attr) {
 362         case hwmon_temp_min_alarm:
 363                 bit = channel ? ADT7411_STAT_1_EXT_TEMP_LOW
 364                               : ADT7411_STAT_1_INT_TEMP_LOW;
 365                 break;
 366         case hwmon_temp_max_alarm:
 367                 bit = channel ? ADT7411_STAT_1_EXT_TEMP_HIGH_AIN1
 368                               : ADT7411_STAT_1_INT_TEMP_HIGH;
 369                 break;
 370         case hwmon_temp_fault:
 371                 bit = ADT7411_STAT_1_EXT_TEMP_FAULT;
 372                 break;
 373         default:
 374                 return -EOPNOTSUPP;
 375         }
 376
 377         *val = !!(ret & bit);
 378         return 0;
 379 }
 380
 381 static int adt7411_read_temp(struct device *dev, u32 attr, int channel,
 382                              long *val)
 383 {
 384         struct adt7411_data *data = dev_get_drvdata(dev);
 385         struct i2c_client *client = data->client;
 386         int ret, reg, regl, regh;
 387
 388         switch (attr) {
 389         case hwmon_temp_input:
 390                 regl = channel ? ADT7411_REG_EXT_TEMP_AIN14_LSB :
 391                                  ADT7411_REG_INT_TEMP_VDD_LSB;
 392                 regh = channel ? ADT7411_REG_EXT_TEMP_AIN1_MSB :
 393                                  ADT7411_REG_INT_TEMP_MSB;
 394                 ret = adt7411_read_10_bit(client, regl, regh, 0);
 395                 if (ret < 0)
 396                         return ret;
 397                 ret = ret & 0x200 ? ret - 0x400 : ret; /* 10 bit signed */
 398                 *val = ret * 250;
 399                 return 0;
 400         case hwmon_temp_min:
 401         case hwmon_temp_max:
 402                 reg = (attr == hwmon_temp_min)
 403                         ? ADT7411_REG_TEMP_LOW(channel)
 404                         : ADT7411_REG_TEMP_HIGH(channel);
 405                 ret = i2c_smbus_read_byte_data(client, reg);
 406                 if (ret < 0)
 407                         return ret;
 408                 ret = ret & 0x80 ? ret - 0x100 : ret; /* 8 bit signed */
 409                 *val = ret * 1000;
 410                 return 0;
 411         case hwmon_temp_min_alarm:
 412         case hwmon_temp_max_alarm:
 413         case hwmon_temp_fault:
 414                 return adt7411_read_temp_alarm(dev, attr, channel, val);
 415         default:
 416                 return -EOPNOTSUPP;
 417         }
 418 }
 419
 420 static int adt7411_read(struct device *dev, enum hwmon_sensor_types type,
 421                         u32 attr, int channel, long *val)
 422 {
 423         switch (type) {
 424         case hwmon_in:
 425                 return adt7411_read_in(dev, attr, channel, val);
 426         case hwmon_temp:
 427                 return adt7411_read_temp(dev, attr, channel, val);
 428         default:
 429                 return -EOPNOTSUPP;
 430         }
 431 }
 432
 433 static int adt7411_write_in_vdd(struct device *dev, u32 attr, long val)
 434 {
 435         struct adt7411_data *data = dev_get_drvdata(dev);
 436         struct i2c_client *client = data->client;
 437         int reg;
 438
 439         val = clamp_val(val, 0, 255 * 7000 / 256);
 440         val = DIV_ROUND_CLOSEST(val * 256, 7000);
 441
 442         switch (attr) {
 443         case hwmon_in_min:
 444                 reg = ADT7411_REG_VDD_LOW;
 445                 break;
 446         case hwmon_in_max:
 447                 reg = ADT7411_REG_VDD_HIGH;
 448                 break;
 449         default:
 450                 return -EOPNOTSUPP;
 451         }
 452
 453         return i2c_smbus_write_byte_data(client, reg, val);
 454 }
 455
 456 static int adt7411_write_in_chan(struct device *dev, u32 attr, int channel,
 457                                  long val)
 458 {
 459         struct adt7411_data *data = dev_get_drvdata(dev);
 460         struct i2c_client *client = data->client;
 461         int ret, reg;
 462
 463         mutex_lock(&data->update_lock);
 464         ret = adt7411_update_vref(dev);
 465         if (ret < 0)
 466                 goto exit_unlock;
 467         val = clamp_val(val, 0, 255 * data->vref_cached / 256);
 468         val = DIV_ROUND_CLOSEST(val * 256, data->vref_cached);
 469
 470         switch (attr) {
 471         case hwmon_in_min:
 472                 reg = ADT7411_REG_IN_LOW(channel);
 473                 break;
 474         case hwmon_in_max:
 475                 reg = ADT7411_REG_IN_HIGH(channel);
 476                 break;
 477         default:
 478                 ret = -EOPNOTSUPP;
 479                 goto exit_unlock;
 480         }
 481
 482         ret = i2c_smbus_write_byte_data(client, reg, val);
 483  exit_unlock:
 484         mutex_unlock(&data->update_lock);
 485         return ret;
 486 }
 487
 488 static int adt7411_write_in(struct device *dev, u32 attr, int channel,
 489                             long val)
 490 {
 491         if (channel == 0)
 492                 return adt7411_write_in_vdd(dev, attr, val);
 493         else
 494                 return adt7411_write_in_chan(dev, attr, channel, val);
 495 }
 496
 497 static int adt7411_write_temp(struct device *dev, u32 attr, int channel,
 498                               long val)
 499 {
 500         struct adt7411_data *data = dev_get_drvdata(dev);
 501         struct i2c_client *client = data->client;
 502         int reg;
 503
 504         val = clamp_val(val, -128000, 127000);
 505         val = DIV_ROUND_CLOSEST(val, 1000);
 506
 507         switch (attr) {
 508         case hwmon_temp_min:
 509                 reg = ADT7411_REG_TEMP_LOW(channel);
 510                 break;
 511         case hwmon_temp_max:
 512                 reg = ADT7411_REG_TEMP_HIGH(channel);
 513                 break;
 514         default:
 515                 return -EOPNOTSUPP;
 516         }
 517
 518         return i2c_smbus_write_byte_data(client, reg, val);
 519 }
 520
 521 static int adt7411_write(struct device *dev, enum hwmon_sensor_types type,
 522                          u32 attr, int channel, long val)
 523 {
 524         switch (type) {
 525         case hwmon_in:
 526                 return adt7411_write_in(dev, attr, channel, val);
 527         case hwmon_temp:
 528                 return adt7411_write_temp(dev, attr, channel, val);
 529         default:
 530                 return -EOPNOTSUPP;
 531         }
 532 }
 533
 534 static umode_t adt7411_is_visible(const void *_data,
 535                                   enum hwmon_sensor_types type,
 536                                   u32 attr, int channel)
 537 {
 538         const struct adt7411_data *data = _data;
 539         bool visible;
 540
 541         switch (type) {
 542         case hwmon_in:
 543                 visible = channel == 0 || channel >= 3 || !data->use_ext_temp;
 544                 switch (attr) {
 545                 case hwmon_in_input:
 546                 case hwmon_in_alarm:
 547                         return visible ? S_IRUGO : 0;
 548                 case hwmon_in_min:
 549                 case hwmon_in_max:
 550                         return visible ? S_IRUGO | S_IWUSR : 0;
 551                 }
 552                 break;
 553         case hwmon_temp:
 554                 visible = channel == 0 || data->use_ext_temp;
 555                 switch (attr) {
 556                 case hwmon_temp_input:
 557                 case hwmon_temp_min_alarm:
 558                 case hwmon_temp_max_alarm:
 559                 case hwmon_temp_fault:
 560                         return visible ? S_IRUGO : 0;
 561                 case hwmon_temp_min:
 562                 case hwmon_temp_max:
 563                         return visible ? S_IRUGO | S_IWUSR : 0;
 564                 }
 565                 break;
 566         default:
 567                 break;
 568         }
 569         return 0;
 570 }
 571
 572 static int adt7411_detect(struct i2c_client *client,
 573                           struct i2c_board_info *info)
 574 {
 575         int val;
 576
 577         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 578                 return -ENODEV;
 579
 580         val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
 581         if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
 582                 dev_dbg(&client->dev,
 583                         "Wrong manufacturer ID. Got %d, expected %d\n",
 584                         val, ADT7411_MANUFACTURER_ID);
 585                 return -ENODEV;
 586         }
 587
 588         val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
 589         if (val < 0 || val != ADT7411_DEVICE_ID) {
 590                 dev_dbg(&client->dev,
 591                         "Wrong device ID. Got %d, expected %d\n",
 592                         val, ADT7411_DEVICE_ID);
 593                 return -ENODEV;
 594         }
 595
 596         strlcpy(info->type, "adt7411", I2C_NAME_SIZE);
 597
 598         return 0;
 599 }
 600
 601 static int adt7411_init_device(struct adt7411_data *data)
 602 {
 603         int ret;
 604         u8 val;
 605
 606         ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG3);
 607         if (ret < 0)
 608                 return ret;
 609
 610         /*
 611          * We must only write zero to bit 1 and bit 2 and only one to bit 3
 612          * according to the datasheet.
 613          */
 614         val = ret;
 615         val &= ~(ADT7411_CFG3_RESERVED_BIT1 | ADT7411_CFG3_RESERVED_BIT2);
 616         val |= ADT7411_CFG3_RESERVED_BIT3;
 617
 618         ret = i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG3, val);
 619         if (ret < 0)
 620                 return ret;
 621
 622         ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG1);
 623         if (ret < 0)
 624                 return ret;
 625
 626         data->use_ext_temp = ret & ADT7411_CFG1_EXT_TDM;
 627
 628         /*
 629          * We must only write zero to bit 1 and only one to bit 3 according to
 630          * the datasheet.
 631          */
 632         val = ret;
 633         val &= ~ADT7411_CFG1_RESERVED_BIT1;
 634         val |= ADT7411_CFG1_RESERVED_BIT3;
 635
 636         /* enable monitoring */
 637         val |= ADT7411_CFG1_START_MONITOR;
 638
 639         return i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG1, val);
 640 }
 641
 642 static const u32 adt7411_in_config[] = {
 643         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 644         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 645         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 646         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 647         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 648         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 649         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 650         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 651         HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_ALARM,
 652         0
 653 };
 654
 655 static const struct hwmon_channel_info adt7411_in = {
 656         .type = hwmon_in,
 657         .config = adt7411_in_config,
 658 };
 659
 660 static const u32 adt7411_temp_config[] = {
 661         HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MIN_ALARM |
 662                 HWMON_T_MAX | HWMON_T_MAX_ALARM,
 663         HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MIN_ALARM |
 664                 HWMON_T_MAX | HWMON_T_MAX_ALARM | HWMON_T_FAULT,
 665         0
 666 };
 667
 668 static const struct hwmon_channel_info adt7411_temp = {
 669         .type = hwmon_temp,
 670         .config = adt7411_temp_config,
 671 };
 672
 673 static const struct hwmon_channel_info *adt7411_info[] = {
 674         &adt7411_in,
 675         &adt7411_temp,
 676         NULL
 677 };
 678
 679 static const struct hwmon_ops adt7411_hwmon_ops = {
 680         .is_visible = adt7411_is_visible,
 681         .read = adt7411_read,
 682         .write = adt7411_write,
 683 };
 684
 685 static const struct hwmon_chip_info adt7411_chip_info = {
 686         .ops = &adt7411_hwmon_ops,
 687         .info = adt7411_info,
 688 };
 689
 690 static int adt7411_probe(struct i2c_client *client,
 691                                    const struct i2c_device_id *id)
 692 {
 693         struct device *dev = &client->dev;
 694         struct adt7411_data *data;
 695         struct device *hwmon_dev;
 696         int ret;
 697
 698         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 699         if (!data)
 700                 return -ENOMEM;
 701
 702         i2c_set_clientdata(client, data);
 703         data->client = client;
 704         mutex_init(&data->device_lock);
 705         mutex_init(&data->update_lock);
 706
 707         ret = adt7411_init_device(data);
 708         if (ret < 0)
 709                 return ret;
 710
 711         /* force update on first occasion */
 712         data->next_update = jiffies;
 713
 714         hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 715                                                          data,
 716                                                          &adt7411_chip_info,
 717                                                          adt7411_groups);
 718         return PTR_ERR_OR_ZERO(hwmon_dev);
 719 }
 720
 721 static const struct i2c_device_id adt7411_id[] = {
 722         { "adt7411", 0 },
 723         { }
 724 };
 725 MODULE_DEVICE_TABLE(i2c, adt7411_id);
 726
 727 static struct i2c_driver adt7411_driver = {
 728         .driver         = {
 729                 .name           = "adt7411",
 730         },
 731         .probe  = adt7411_probe,
 732         .id_table = adt7411_id,
 733         .detect = adt7411_detect,
 734         .address_list = normal_i2c,
 735         .class = I2C_CLASS_HWMON,
 736 };
 737
 738 module_i2c_driver(adt7411_driver);
 739
 740 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
 741         "Wolfram Sang <w.sang@pengutronix.de>");
 742 MODULE_DESCRIPTION("ADT7411 driver");
 743 MODULE_LICENSE("GPL v2");