drivers/hwmon/ftsteutates.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Support for the FTS Systemmonitoring Chip "Teutates"
   4  *
   5  * Copyright (C) 2016 Fujitsu Technology Solutions GmbH,
   6  *                Thilo Cestonaro <thilo.cestonaro@ts.fujitsu.com>
   7  */
   8 #include <linux/err.h>
   9 #include <linux/hwmon.h>
  10 #include <linux/i2c.h>
  11 #include <linux/init.h>
  12 #include <linux/jiffies.h>
  13 #include <linux/math.h>
  14 #include <linux/module.h>
  15 #include <linux/mutex.h>
  16 #include <linux/slab.h>
  17 #include <linux/watchdog.h>
  18
  19 #define FTS_DEVICE_ID_REG               0x0000
  20 #define FTS_DEVICE_REVISION_REG         0x0001
  21 #define FTS_DEVICE_STATUS_REG           0x0004
  22 #define FTS_SATELLITE_STATUS_REG        0x0005
  23 #define FTS_EVENT_STATUS_REG            0x0006
  24 #define FTS_GLOBAL_CONTROL_REG          0x0007
  25
  26 #define FTS_DEVICE_DETECT_REG_1         0x0C
  27 #define FTS_DEVICE_DETECT_REG_2         0x0D
  28 #define FTS_DEVICE_DETECT_REG_3         0x0E
  29
  30 #define FTS_SENSOR_EVENT_REG            0x0010
  31
  32 #define FTS_FAN_EVENT_REG               0x0014
  33 #define FTS_FAN_PRESENT_REG             0x0015
  34
  35 #define FTS_POWER_ON_TIME_COUNTER_A     0x007A
  36 #define FTS_POWER_ON_TIME_COUNTER_B     0x007B
  37 #define FTS_POWER_ON_TIME_COUNTER_C     0x007C
  38
  39 #define FTS_PAGE_SELECT_REG             0x007F
  40
  41 #define FTS_WATCHDOG_TIME_PRESET        0x000B
  42 #define FTS_WATCHDOG_CONTROL            0x5081
  43
  44 #define FTS_NO_FAN_SENSORS              0x08
  45 #define FTS_NO_TEMP_SENSORS             0x10
  46 #define FTS_NO_VOLT_SENSORS             0x04
  47
  48 #define FTS_FAN_SOURCE_INVALID          0xff
  49
  50 static const unsigned short normal_i2c[] = { 0x73, I2C_CLIENT_END };
  51
  52 static const struct i2c_device_id fts_id[] = {
  53         { "ftsteutates", 0 },
  54         { }
  55 };
  56 MODULE_DEVICE_TABLE(i2c, fts_id);
  57
  58 enum WATCHDOG_RESOLUTION {
  59         seconds = 1,
  60         minutes = 60
  61 };
  62
  63 struct fts_data {
  64         struct i2c_client *client;
  65         /* update sensor data lock */
  66         struct mutex update_lock;
  67         /* read/write register lock */
  68         struct mutex access_lock;
  69         unsigned long last_updated; /* in jiffies */
  70         struct watchdog_device wdd;
  71         enum WATCHDOG_RESOLUTION resolution;
  72         bool valid; /* false until following fields are valid */
  73
  74         u8 volt[FTS_NO_VOLT_SENSORS];
  75
  76         u8 temp_input[FTS_NO_TEMP_SENSORS];
  77         u8 temp_alarm;
  78
  79         u8 fan_present;
  80         u8 fan_input[FTS_NO_FAN_SENSORS]; /* in rps */
  81         u8 fan_source[FTS_NO_FAN_SENSORS];
  82         u8 fan_alarm;
  83 };
  84
  85 #define FTS_REG_FAN_INPUT(idx) ((idx) + 0x20)
  86 #define FTS_REG_FAN_SOURCE(idx) ((idx) + 0x30)
  87 #define FTS_REG_FAN_CONTROL(idx) (((idx) << 16) + 0x4881)
  88
  89 #define FTS_REG_TEMP_INPUT(idx) ((idx) + 0x40)
  90 #define FTS_REG_TEMP_CONTROL(idx) (((idx) << 16) + 0x0681)
  91
  92 #define FTS_REG_VOLT(idx) ((idx) + 0x18)
  93
  94 /*****************************************************************************/
  95 /* I2C Helper functions                                                      */
  96 /*****************************************************************************/
  97 static int fts_read_byte(struct i2c_client *client, unsigned short reg)
  98 {
  99         int ret;
 100         unsigned char page = reg >> 8;
 101         struct fts_data *data = dev_get_drvdata(&client->dev);
 102
 103         mutex_lock(&data->access_lock);
 104
 105         dev_dbg(&client->dev, "page select - page: 0x%.02x\n", page);
 106         ret = i2c_smbus_write_byte_data(client, FTS_PAGE_SELECT_REG, page);
 107         if (ret < 0)
 108                 goto error;
 109
 110         reg &= 0xFF;
 111         ret = i2c_smbus_read_byte_data(client, reg);
 112         dev_dbg(&client->dev, "read - reg: 0x%.02x: val: 0x%.02x\n", reg, ret);
 113
 114 error:
 115         mutex_unlock(&data->access_lock);
 116         return ret;
 117 }
 118
 119 static int fts_write_byte(struct i2c_client *client, unsigned short reg,
 120                           unsigned char value)
 121 {
 122         int ret;
 123         unsigned char page = reg >> 8;
 124         struct fts_data *data = dev_get_drvdata(&client->dev);
 125
 126         mutex_lock(&data->access_lock);
 127
 128         dev_dbg(&client->dev, "page select - page: 0x%.02x\n", page);
 129         ret = i2c_smbus_write_byte_data(client, FTS_PAGE_SELECT_REG, page);
 130         if (ret < 0)
 131                 goto error;
 132
 133         reg &= 0xFF;
 134         dev_dbg(&client->dev,
 135                 "write - reg: 0x%.02x: val: 0x%.02x\n", reg, value);
 136         ret = i2c_smbus_write_byte_data(client, reg, value);
 137
 138 error:
 139         mutex_unlock(&data->access_lock);
 140         return ret;
 141 }
 142
 143 /*****************************************************************************/
 144 /* Data Updater Helper function                                              */
 145 /*****************************************************************************/
 146 static int fts_update_device(struct fts_data *data)
 147 {
 148         int i;
 149         int err = 0;
 150
 151         mutex_lock(&data->update_lock);
 152         if (!time_after(jiffies, data->last_updated + 2 * HZ) && data->valid)
 153                 goto exit;
 154
 155         err = fts_read_byte(data->client, FTS_DEVICE_STATUS_REG);
 156         if (err < 0)
 157                 goto exit;
 158
 159         data->valid = !!(err & 0x02); /* Data not ready yet */
 160         if (unlikely(!data->valid)) {
 161                 err = -EAGAIN;
 162                 goto exit;
 163         }
 164
 165         err = fts_read_byte(data->client, FTS_FAN_PRESENT_REG);
 166         if (err < 0)
 167                 goto exit;
 168         data->fan_present = err;
 169
 170         err = fts_read_byte(data->client, FTS_FAN_EVENT_REG);
 171         if (err < 0)
 172                 goto exit;
 173         data->fan_alarm = err;
 174
 175         for (i = 0; i < FTS_NO_FAN_SENSORS; i++) {
 176                 if (data->fan_present & BIT(i)) {
 177                         err = fts_read_byte(data->client, FTS_REG_FAN_INPUT(i));
 178                         if (err < 0)
 179                                 goto exit;
 180                         data->fan_input[i] = err;
 181
 182                         err = fts_read_byte(data->client,
 183                                             FTS_REG_FAN_SOURCE(i));
 184                         if (err < 0)
 185                                 goto exit;
 186                         data->fan_source[i] = err;
 187                 } else {
 188                         data->fan_input[i] = 0;
 189                         data->fan_source[i] = FTS_FAN_SOURCE_INVALID;
 190                 }
 191         }
 192
 193         err = fts_read_byte(data->client, FTS_SENSOR_EVENT_REG);
 194         if (err < 0)
 195                 goto exit;
 196         data->temp_alarm = err;
 197
 198         for (i = 0; i < FTS_NO_TEMP_SENSORS; i++) {
 199                 err = fts_read_byte(data->client, FTS_REG_TEMP_INPUT(i));
 200                 if (err < 0)
 201                         goto exit;
 202                 data->temp_input[i] = err;
 203         }
 204
 205         for (i = 0; i < FTS_NO_VOLT_SENSORS; i++) {
 206                 err = fts_read_byte(data->client, FTS_REG_VOLT(i));
 207                 if (err < 0)
 208                         goto exit;
 209                 data->volt[i] = err;
 210         }
 211         data->last_updated = jiffies;
 212         err = 0;
 213 exit:
 214         mutex_unlock(&data->update_lock);
 215         return err;
 216 }
 217
 218 /*****************************************************************************/
 219 /* Watchdog functions                                                        */
 220 /*****************************************************************************/
 221 static int fts_wd_set_resolution(struct fts_data *data,
 222                                  enum WATCHDOG_RESOLUTION resolution)
 223 {
 224         int ret;
 225
 226         if (data->resolution == resolution)
 227                 return 0;
 228
 229         ret = fts_read_byte(data->client, FTS_WATCHDOG_CONTROL);
 230         if (ret < 0)
 231                 return ret;
 232
 233         if ((resolution == seconds && ret & BIT(1)) ||
 234             (resolution == minutes && (ret & BIT(1)) == 0)) {
 235                 data->resolution = resolution;
 236                 return 0;
 237         }
 238
 239         if (resolution == seconds)
 240                 ret |= BIT(1);
 241         else
 242                 ret &= ~BIT(1);
 243
 244         ret = fts_write_byte(data->client, FTS_WATCHDOG_CONTROL, ret);
 245         if (ret < 0)
 246                 return ret;
 247
 248         data->resolution = resolution;
 249         return ret;
 250 }
 251
 252 static int fts_wd_set_timeout(struct watchdog_device *wdd, unsigned int timeout)
 253 {
 254         struct fts_data *data;
 255         enum WATCHDOG_RESOLUTION resolution = seconds;
 256         int ret;
 257
 258         data = watchdog_get_drvdata(wdd);
 259         /* switch watchdog resolution to minutes if timeout does not fit
 260          * into a byte
 261          */
 262         if (timeout > 0xFF) {
 263                 timeout = DIV_ROUND_UP(timeout, 60) * 60;
 264                 resolution = minutes;
 265         }
 266
 267         ret = fts_wd_set_resolution(data, resolution);
 268         if (ret < 0)
 269                 return ret;
 270
 271         wdd->timeout = timeout;
 272         return 0;
 273 }
 274
 275 static int fts_wd_start(struct watchdog_device *wdd)
 276 {
 277         struct fts_data *data = watchdog_get_drvdata(wdd);
 278
 279         return fts_write_byte(data->client, FTS_WATCHDOG_TIME_PRESET,
 280                               wdd->timeout / (u8)data->resolution);
 281 }
 282
 283 static int fts_wd_stop(struct watchdog_device *wdd)
 284 {
 285         struct fts_data *data;
 286
 287         data = watchdog_get_drvdata(wdd);
 288         return fts_write_byte(data->client, FTS_WATCHDOG_TIME_PRESET, 0);
 289 }
 290
 291 static const struct watchdog_info fts_wd_info = {
 292         .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
 293         .identity = "FTS Teutates Hardware Watchdog",
 294 };
 295
 296 static const struct watchdog_ops fts_wd_ops = {
 297         .owner = THIS_MODULE,
 298         .start = fts_wd_start,
 299         .stop = fts_wd_stop,
 300         .set_timeout = fts_wd_set_timeout,
 301 };
 302
 303 static int fts_watchdog_init(struct fts_data *data)
 304 {
 305         int timeout, ret;
 306
 307         watchdog_set_drvdata(&data->wdd, data);
 308
 309         timeout = fts_read_byte(data->client, FTS_WATCHDOG_TIME_PRESET);
 310         if (timeout < 0)
 311                 return timeout;
 312
 313         /* watchdog not running, set timeout to a default of 60 sec. */
 314         if (timeout == 0) {
 315                 ret = fts_wd_set_resolution(data, seconds);
 316                 if (ret < 0)
 317                         return ret;
 318                 data->wdd.timeout = 60;
 319         } else {
 320                 ret = fts_read_byte(data->client, FTS_WATCHDOG_CONTROL);
 321                 if (ret < 0)
 322                         return ret;
 323
 324                 data->resolution = ret & BIT(1) ? seconds : minutes;
 325                 data->wdd.timeout = timeout * (u8)data->resolution;
 326                 set_bit(WDOG_HW_RUNNING, &data->wdd.status);
 327         }
 328
 329         /* Register our watchdog part */
 330         data->wdd.info = &fts_wd_info;
 331         data->wdd.ops = &fts_wd_ops;
 332         data->wdd.parent = &data->client->dev;
 333         data->wdd.min_timeout = 1;
 334
 335         /* max timeout 255 minutes. */
 336         data->wdd.max_hw_heartbeat_ms = 0xFF * 60 * MSEC_PER_SEC;
 337
 338         return devm_watchdog_register_device(&data->client->dev, &data->wdd);
 339 }
 340
 341 static umode_t fts_is_visible(const void *devdata, enum hwmon_sensor_types type, u32 attr,
 342                               int channel)
 343 {
 344         switch (type) {
 345         case hwmon_temp:
 346                 switch (attr) {
 347                 case hwmon_temp_input:
 348                 case hwmon_temp_fault:
 349                         return 0444;
 350                 case hwmon_temp_alarm:
 351                         return 0644;
 352                 default:
 353                         break;
 354                 }
 355                 break;
 356         case hwmon_fan:
 357                 switch (attr) {
 358                 case hwmon_fan_input:
 359                 case hwmon_fan_fault:
 360                         return 0444;
 361                 case hwmon_fan_alarm:
 362                         return 0644;
 363                 default:
 364                         break;
 365                 }
 366                 break;
 367         case hwmon_pwm:
 368         case hwmon_in:
 369                 return 0444;
 370         default:
 371                 break;
 372         }
 373
 374         return 0;
 375 }
 376
 377 static int fts_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
 378                     long *val)
 379 {
 380         struct fts_data *data = dev_get_drvdata(dev);
 381         int ret = fts_update_device(data);
 382
 383         if (ret < 0)
 384                 return ret;
 385
 386         switch (type) {
 387         case hwmon_temp:
 388                 switch (attr) {
 389                 case hwmon_temp_input:
 390                         *val = (data->temp_input[channel] - 64) * 1000;
 391
 392                         return 0;
 393                 case hwmon_temp_alarm:
 394                         *val = !!(data->temp_alarm & BIT(channel));
 395
 396                         return 0;
 397                 case hwmon_temp_fault:
 398                         /* 00h Temperature = Sensor Error */;
 399                         *val = (data->temp_input[channel] == 0);
 400
 401                         return 0;
 402                 default:
 403                         break;
 404                 }
 405                 break;
 406         case hwmon_fan:
 407                 switch (attr) {
 408                 case hwmon_fan_input:
 409                         *val = data->fan_input[channel] * 60;
 410
 411                         return 0;
 412                 case hwmon_fan_alarm:
 413                         *val = !!(data->fan_alarm & BIT(channel));
 414
 415                         return 0;
 416                 case hwmon_fan_fault:
 417                         *val = !(data->fan_present & BIT(channel));
 418
 419                         return 0;
 420                 default:
 421                         break;
 422                 }
 423                 break;
 424         case hwmon_pwm:
 425                 switch (attr) {
 426                 case hwmon_pwm_auto_channels_temp:
 427                         if (data->fan_source[channel] == FTS_FAN_SOURCE_INVALID)
 428                                 *val = 0;
 429                         else
 430                                 *val = BIT(data->fan_source[channel]);
 431
 432                         return 0;
 433                 default:
 434                         break;
 435                 }
 436                 break;
 437         case hwmon_in:
 438                 switch (attr) {
 439                 case hwmon_in_input:
 440                         *val = DIV_ROUND_CLOSEST(data->volt[channel] * 3300, 255);
 441
 442                         return 0;
 443                 default:
 444                         break;
 445                 }
 446                 break;
 447         default:
 448                 break;
 449         }
 450
 451         return -EOPNOTSUPP;
 452 }
 453
 454 static int fts_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
 455                      long val)
 456 {
 457         struct fts_data *data = dev_get_drvdata(dev);
 458         int ret = fts_update_device(data);
 459
 460         if (ret < 0)
 461                 return ret;
 462
 463         switch (type) {
 464         case hwmon_temp:
 465                 switch (attr) {
 466                 case hwmon_temp_alarm:
 467                         if (val)
 468                                 return -EINVAL;
 469
 470                         mutex_lock(&data->update_lock);
 471                         ret = fts_read_byte(data->client, FTS_REG_TEMP_CONTROL(channel));
 472                         if (ret >= 0)
 473                                 ret = fts_write_byte(data->client, FTS_REG_TEMP_CONTROL(channel),
 474                                                      ret | 0x1);
 475                         if (ret >= 0)
 476                                 data->valid = false;
 477
 478                         mutex_unlock(&data->update_lock);
 479                         if (ret < 0)
 480                                 return ret;
 481
 482                         return 0;
 483                 default:
 484                         break;
 485                 }
 486                 break;
 487         case hwmon_fan:
 488                 switch (attr) {
 489                 case hwmon_fan_alarm:
 490                         if (val)
 491                                 return -EINVAL;
 492
 493                         mutex_lock(&data->update_lock);
 494                         ret = fts_read_byte(data->client, FTS_REG_FAN_CONTROL(channel));
 495                         if (ret >= 0)
 496                                 ret = fts_write_byte(data->client, FTS_REG_FAN_CONTROL(channel),
 497                                                      ret | 0x1);
 498                         if (ret >= 0)
 499                                 data->valid = false;
 500
 501                         mutex_unlock(&data->update_lock);
 502                         if (ret < 0)
 503                                 return ret;
 504
 505                         return 0;
 506                 default:
 507                         break;
 508                 }
 509                 break;
 510         default:
 511                 break;
 512         }
 513
 514         return -EOPNOTSUPP;
 515 }
 516
 517 static const struct hwmon_ops fts_ops = {
 518         .is_visible = fts_is_visible,
 519         .read = fts_read,
 520         .write = fts_write,
 521 };
 522
 523 static const struct hwmon_channel_info * const fts_info[] = {
 524         HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
 525         HWMON_CHANNEL_INFO(temp,
 526                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 527                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 528                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 529                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 530                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 531                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 532                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 533                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 534                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 535                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 536                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 537                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 538                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 539                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 540                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT,
 541                            HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_FAULT
 542                            ),
 543         HWMON_CHANNEL_INFO(fan,
 544                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT,
 545                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT,
 546                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT,
 547                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT,
 548                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT,
 549                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT,
 550                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT,
 551                            HWMON_F_INPUT | HWMON_F_ALARM | HWMON_F_FAULT
 552                            ),
 553         HWMON_CHANNEL_INFO(pwm,
 554                            HWMON_PWM_AUTO_CHANNELS_TEMP,
 555                            HWMON_PWM_AUTO_CHANNELS_TEMP,
 556                            HWMON_PWM_AUTO_CHANNELS_TEMP,
 557                            HWMON_PWM_AUTO_CHANNELS_TEMP,
 558                            HWMON_PWM_AUTO_CHANNELS_TEMP,
 559                            HWMON_PWM_AUTO_CHANNELS_TEMP,
 560                            HWMON_PWM_AUTO_CHANNELS_TEMP,
 561                            HWMON_PWM_AUTO_CHANNELS_TEMP
 562                            ),
 563         HWMON_CHANNEL_INFO(in,
 564                            HWMON_I_INPUT,
 565                            HWMON_I_INPUT,
 566                            HWMON_I_INPUT,
 567                            HWMON_I_INPUT
 568                            ),
 569         NULL
 570 };
 571
 572 static const struct hwmon_chip_info fts_chip_info = {
 573         .ops = &fts_ops,
 574         .info = fts_info,
 575 };
 576
 577 /*****************************************************************************/
 578 /* Module initialization / remove functions                                  */
 579 /*****************************************************************************/
 580 static int fts_detect(struct i2c_client *client,
 581                       struct i2c_board_info *info)
 582 {
 583         int val;
 584
 585         /* detection works with revision greater or equal to 0x2b */
 586         val = i2c_smbus_read_byte_data(client, FTS_DEVICE_REVISION_REG);
 587         if (val < 0x2b)
 588                 return -ENODEV;
 589
 590         /* Device Detect Regs must have 0x17 0x34 and 0x54 */
 591         val = i2c_smbus_read_byte_data(client, FTS_DEVICE_DETECT_REG_1);
 592         if (val != 0x17)
 593                 return -ENODEV;
 594
 595         val = i2c_smbus_read_byte_data(client, FTS_DEVICE_DETECT_REG_2);
 596         if (val != 0x34)
 597                 return -ENODEV;
 598
 599         val = i2c_smbus_read_byte_data(client, FTS_DEVICE_DETECT_REG_3);
 600         if (val != 0x54)
 601                 return -ENODEV;
 602
 603         /*
 604          * 0x10 == Baseboard Management Controller, 0x01 == Teutates
 605          * Device ID Reg needs to be 0x11
 606          */
 607         val = i2c_smbus_read_byte_data(client, FTS_DEVICE_ID_REG);
 608         if (val != 0x11)
 609                 return -ENODEV;
 610
 611         strscpy(info->type, fts_id[0].name, I2C_NAME_SIZE);
 612         info->flags = 0;
 613         return 0;
 614 }
 615
 616 static int fts_probe(struct i2c_client *client)
 617 {
 618         u8 revision;
 619         struct fts_data *data;
 620         int err;
 621         s8 deviceid;
 622         struct device *hwmon_dev;
 623
 624         if (client->addr != 0x73)
 625                 return -ENODEV;
 626
 627         /* Baseboard Management Controller check */
 628         deviceid = i2c_smbus_read_byte_data(client, FTS_DEVICE_ID_REG);
 629         if (deviceid > 0 && (deviceid & 0xF0) == 0x10) {
 630                 switch (deviceid & 0x0F) {
 631                 case 0x01:
 632                         break;
 633                 default:
 634                         dev_dbg(&client->dev,
 635                                 "No Baseboard Management Controller\n");
 636                         return -ENODEV;
 637                 }
 638         } else {
 639                 dev_dbg(&client->dev, "No fujitsu board\n");
 640                 return -ENODEV;
 641         }
 642
 643         data = devm_kzalloc(&client->dev, sizeof(struct fts_data),
 644                             GFP_KERNEL);
 645         if (!data)
 646                 return -ENOMEM;
 647
 648         mutex_init(&data->update_lock);
 649         mutex_init(&data->access_lock);
 650         data->client = client;
 651         dev_set_drvdata(&client->dev, data);
 652
 653         err = i2c_smbus_read_byte_data(client, FTS_DEVICE_REVISION_REG);
 654         if (err < 0)
 655                 return err;
 656         revision = err;
 657
 658         hwmon_dev = devm_hwmon_device_register_with_info(&client->dev, "ftsteutates", data,
 659                                                          &fts_chip_info, NULL);
 660         if (IS_ERR(hwmon_dev))
 661                 return PTR_ERR(hwmon_dev);
 662
 663         err = fts_watchdog_init(data);
 664         if (err)
 665                 return err;
 666
 667         dev_info(&client->dev, "Detected FTS Teutates chip, revision: %d.%d\n",
 668                  (revision & 0xF0) >> 4, revision & 0x0F);
 669         return 0;
 670 }
 671
 672 /*****************************************************************************/
 673 /* Module Details                                                            */
 674 /*****************************************************************************/
 675 static struct i2c_driver fts_driver = {
 676         .class = I2C_CLASS_HWMON,
 677         .driver = {
 678                 .name = "ftsteutates",
 679         },
 680         .id_table = fts_id,
 681         .probe = fts_probe,
 682         .detect = fts_detect,
 683         .address_list = normal_i2c,
 684 };
 685
 686 module_i2c_driver(fts_driver);
 687
 688 MODULE_AUTHOR("Thilo Cestonaro <thilo.cestonaro@ts.fujitsu.com>");
 689 MODULE_DESCRIPTION("FTS Teutates driver");
 690 MODULE_LICENSE("GPL");