drivers/hwmon/max31760.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 #include <linux/bitfield.h>
   4 #include <linux/bits.h>
   5 #include <linux/err.h>
   6 #include <linux/hwmon.h>
   7 #include <linux/hwmon-sysfs.h>
   8 #include <linux/i2c.h>
   9 #include <linux/regmap.h>
  10 #include <linux/util_macros.h>
  11
  12 #define REG_CR1         0x00
  13 #define CR1_HYST        BIT(5)
  14 #define CR1_DRV         GENMASK(4, 3)
  15 #define CR1_TEMP_SRC    GENMASK(1, 0)
  16 #define REG_CR2         0x01
  17 #define CR2_STBY        BIT(7)
  18 #define CR2_ALERTS      BIT(6)
  19 #define CR2_DFC         BIT(0)
  20 #define REG_CR3         0x02
  21 #define REG_PWMR        0x50
  22 #define REG_PWMV        0x51
  23 #define REG_STATUS      0x5A
  24 #define STATUS_ALARM_CRIT(ch)   BIT(2 + 2 * (ch))
  25 #define STATUS_ALARM_MAX(ch)    BIT(3 + 2 * (ch))
  26 #define STATUS_RDFA             BIT(6)
  27
  28 #define REG_TACH(ch)            (0x52 + (ch) * 2)
  29 #define REG_TEMP_INPUT(ch)      (0x56 + (ch) * 2)
  30 #define REG_TEMP_MAX(ch)        (0x06 + (ch) * 2)
  31 #define REG_TEMP_CRIT(ch)       (0x0A + (ch) * 2)
  32
  33 #define TEMP11_FROM_REG(reg)    ((reg) / 32 * 125)
  34 #define TEMP11_TO_REG(val)      (DIV_ROUND_CLOSEST(clamp_val((val), -128000, \
  35                                                              127875), 125) * 32)
  36
  37 #define LUT_SIZE        48
  38
  39 #define REG_LUT(index)          (0x20 + (index))
  40
  41 struct max31760_state {
  42         struct regmap *regmap;
  43
  44         struct lut_attribute {
  45                 char name[24];
  46                 struct sensor_device_attribute sda;
  47         } lut[LUT_SIZE];
  48
  49         struct attribute *attrs[LUT_SIZE + 2];
  50         struct attribute_group group;
  51         const struct attribute_group *groups[2];
  52 };
  53
  54 static bool max31760_volatile_reg(struct device *dev, unsigned int reg)
  55 {
  56         return reg > 0x50;
  57 }
  58
  59 static const struct regmap_config regmap_config = {
  60         .reg_bits = 8,
  61         .val_bits = 8,
  62         .max_register = 0x5B,
  63         .cache_type = REGCACHE_RBTREE,
  64         .volatile_reg = max31760_volatile_reg,
  65 };
  66
  67 static const int max31760_pwm_freq[] = {33, 150, 1500, 25000};
  68
  69 static int tach_to_rpm(u16 tach)
  70 {
  71         if (tach == 0)
  72                 tach = 1;
  73
  74         return 60 * 100000 / tach / 2;
  75 }
  76
  77 static int max31760_read(struct device *dev, enum hwmon_sensor_types type,
  78                          u32 attr, int channel, long *val)
  79 {
  80         struct max31760_state *state = dev_get_drvdata(dev);
  81         unsigned int regval;
  82         unsigned int reg_temp;
  83         s16 temp;
  84         u8 reg[2];
  85         int ret;
  86
  87         switch (type) {
  88         case hwmon_temp:
  89                 switch (attr) {
  90                 case hwmon_temp_fault:
  91                         ret = regmap_read(state->regmap, REG_STATUS, &regval);
  92                         if (ret)
  93                                 return ret;
  94
  95                         *val = FIELD_GET(STATUS_RDFA, regval);
  96
  97                         return 0;
  98                 case hwmon_temp_max_alarm:
  99                         ret = regmap_read(state->regmap, REG_STATUS, &regval);
 100                         if (ret)
 101                                 return ret;
 102
 103                         if (channel)
 104                                 *val = FIELD_GET(STATUS_ALARM_MAX(1), regval);
 105                         else
 106                                 *val = FIELD_GET(STATUS_ALARM_MAX(0), regval);
 107
 108                         return 0;
 109                 case hwmon_temp_crit_alarm:
 110                         ret = regmap_read(state->regmap, REG_STATUS, &regval);
 111                         if (ret)
 112                                 return ret;
 113
 114                         if (channel)
 115                                 *val = FIELD_GET(STATUS_ALARM_CRIT(1), regval);
 116                         else
 117                                 *val = FIELD_GET(STATUS_ALARM_CRIT(0), regval);
 118
 119                         return 0;
 120                 case hwmon_temp_input:
 121                         reg_temp = REG_TEMP_INPUT(channel);
 122                         break;
 123                 case hwmon_temp_max:
 124                         reg_temp = REG_TEMP_MAX(channel);
 125                         break;
 126                 case hwmon_temp_crit:
 127                         reg_temp = REG_TEMP_CRIT(channel);
 128                         break;
 129                 default:
 130                         return -EOPNOTSUPP;
 131                 }
 132
 133                 ret = regmap_bulk_read(state->regmap, reg_temp, reg, 2);
 134                 if (ret)
 135                         return ret;
 136
 137                 temp = (reg[0] << 8) | reg[1];
 138
 139                 *val = TEMP11_FROM_REG(temp);
 140
 141                 return 0;
 142         case hwmon_fan:
 143                 switch (attr) {
 144                 case hwmon_fan_input:
 145                         ret = regmap_bulk_read(state->regmap, REG_TACH(channel), reg, 2);
 146                         if (ret)
 147                                 return ret;
 148
 149                         *val = tach_to_rpm(reg[0] * 256 + reg[1]);
 150
 151                         return 0;
 152                 case hwmon_fan_fault:
 153                         ret = regmap_read(state->regmap, REG_STATUS, &regval);
 154                         if (ret)
 155                                 return ret;
 156
 157                         if (channel)
 158                                 *val = FIELD_GET(BIT(1), regval);
 159                         else
 160                                 *val = FIELD_GET(BIT(0), regval);
 161
 162                         return 0;
 163                 case hwmon_fan_enable:
 164                         ret = regmap_read(state->regmap, REG_CR3, &regval);
 165                         if (ret)
 166                                 return ret;
 167
 168                         if (channel)
 169                                 *val = FIELD_GET(BIT(1), regval);
 170                         else
 171                                 *val = FIELD_GET(BIT(0), regval);
 172
 173                         return 0;
 174                 default:
 175                         return -EOPNOTSUPP;
 176                 }
 177         case hwmon_pwm:
 178                 switch (attr) {
 179                 case hwmon_pwm_input:
 180                         ret = regmap_read(state->regmap, REG_PWMV, &regval);
 181                         if (ret)
 182                                 return ret;
 183
 184                         *val = regval;
 185
 186                         return 0;
 187                 case hwmon_pwm_freq:
 188                         ret = regmap_read(state->regmap, REG_CR1, &regval);
 189                         if (ret)
 190                                 return ret;
 191
 192                         regval = FIELD_GET(CR1_DRV, regval);
 193                         if (regval >= ARRAY_SIZE(max31760_pwm_freq))
 194                                 return -EINVAL;
 195
 196                         *val = max31760_pwm_freq[regval];
 197
 198                         return 0;
 199                 case hwmon_pwm_enable:
 200                         ret = regmap_read(state->regmap, REG_CR2, &regval);
 201                         if (ret)
 202                                 return ret;
 203
 204                         *val = 2 - FIELD_GET(CR2_DFC, regval);
 205
 206                         return 0;
 207                 case hwmon_pwm_auto_channels_temp:
 208                         ret = regmap_read(state->regmap, REG_CR1, &regval);
 209                         if (ret)
 210                                 return ret;
 211
 212                         switch (FIELD_GET(CR1_TEMP_SRC, regval)) {
 213                         case 0:
 214                                 *val = 2;
 215                                 break;
 216                         case 1:
 217                                 *val = 1;
 218                                 break;
 219                         case 2:
 220                         case 3:
 221                                 *val = 3;
 222                                 break;
 223                         default:
 224                                 return -EINVAL;
 225                         }
 226
 227                         return 0;
 228                 default:
 229                         return -EOPNOTSUPP;
 230                 }
 231         default:
 232                 return -EOPNOTSUPP;
 233         }
 234 }
 235
 236 static int max31760_write(struct device *dev, enum hwmon_sensor_types type,
 237                           u32 attr, int channel, long val)
 238 {
 239         struct max31760_state *state = dev_get_drvdata(dev);
 240         unsigned int pwm_index;
 241         unsigned int reg_temp;
 242         int temp;
 243         u8 reg_val[2];
 244
 245         switch (type) {
 246         case hwmon_temp:
 247                 switch (attr) {
 248                 case hwmon_temp_max:
 249                         reg_temp = REG_TEMP_MAX(channel);
 250                         break;
 251                 case hwmon_temp_crit:
 252                         reg_temp = REG_TEMP_CRIT(channel);
 253                         break;
 254                 default:
 255                         return -EOPNOTSUPP;
 256                 }
 257
 258                 temp = TEMP11_TO_REG(val);
 259                 reg_val[0] = temp >> 8;
 260                 reg_val[1] = temp & 0xFF;
 261
 262                 return regmap_bulk_write(state->regmap, reg_temp, reg_val, 2);
 263         case hwmon_fan:
 264                 switch (attr) {
 265                 case hwmon_fan_enable:
 266                         if (val == 0)
 267                                 return regmap_clear_bits(state->regmap, REG_CR3, BIT(channel));
 268
 269                         if (val == 1)
 270                                 return regmap_set_bits(state->regmap, REG_CR3, BIT(channel));
 271
 272                         return -EINVAL;
 273                 default:
 274                         return -EOPNOTSUPP;
 275                 }
 276         case hwmon_pwm:
 277                 switch (attr) {
 278                 case hwmon_pwm_input:
 279                         if (val < 0 || val > 255)
 280                                 return -EINVAL;
 281
 282                         return regmap_write(state->regmap, REG_PWMR, val);
 283                 case hwmon_pwm_enable:
 284                         if (val == 1)
 285                                 return regmap_set_bits(state->regmap, REG_CR2, CR2_DFC);
 286
 287                         if (val == 2)
 288                                 return regmap_clear_bits(state->regmap, REG_CR2, CR2_DFC);
 289
 290                         return -EINVAL;
 291                 case hwmon_pwm_freq:
 292                         pwm_index = find_closest(val, max31760_pwm_freq,
 293                                                  ARRAY_SIZE(max31760_pwm_freq));
 294
 295                         return regmap_update_bits(state->regmap,
 296                                                   REG_CR1, CR1_DRV,
 297                                                   FIELD_PREP(CR1_DRV, pwm_index));
 298                 case hwmon_pwm_auto_channels_temp:
 299                         switch (val) {
 300                         case 1:
 301                                 break;
 302                         case 2:
 303                                 val = 0;
 304                                 break;
 305                         case 3:
 306                                 val = 2;
 307                                 break;
 308                         default:
 309                                 return -EINVAL;
 310                         }
 311
 312                         return regmap_update_bits(state->regmap, REG_CR1, CR1_TEMP_SRC, val);
 313                 default:
 314                         return -EOPNOTSUPP;
 315                 }
 316         default:
 317                 return -EOPNOTSUPP;
 318         }
 319 }
 320
 321 static const struct hwmon_channel_info *max31760_info[] = {
 322         HWMON_CHANNEL_INFO(chip,
 323                            HWMON_C_REGISTER_TZ),
 324         HWMON_CHANNEL_INFO(fan,
 325                            HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_ENABLE,
 326                            HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_ENABLE),
 327         HWMON_CHANNEL_INFO(temp,
 328                            HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT | HWMON_T_FAULT |
 329                            HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_LABEL,
 330                            HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
 331                            HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM | HWMON_T_LABEL),
 332         HWMON_CHANNEL_INFO(pwm,
 333                            HWMON_PWM_ENABLE | HWMON_PWM_FREQ | HWMON_PWM_INPUT |
 334                            HWMON_PWM_AUTO_CHANNELS_TEMP),
 335         NULL
 336 };
 337
 338 static umode_t max31760_is_visible(const void *data,
 339                                    enum hwmon_sensor_types type,
 340                                    u32 attr, int channel)
 341 {
 342         switch (type) {
 343         case hwmon_temp:
 344                 switch (attr) {
 345                 case hwmon_temp_input:
 346                 case hwmon_temp_max_alarm:
 347                 case hwmon_temp_crit_alarm:
 348                 case hwmon_temp_fault:
 349                 case hwmon_temp_label:
 350                         return 0444;
 351                 case hwmon_temp_max:
 352                 case hwmon_temp_crit:
 353                         return 0644;
 354                 default:
 355                         return 0;
 356                 }
 357         case hwmon_fan:
 358                 switch (attr) {
 359                 case hwmon_fan_input:
 360                 case hwmon_fan_fault:
 361                         return 0444;
 362                 case hwmon_fan_enable:
 363                         return 0644;
 364                 default:
 365                         return 0;
 366                 }
 367         case hwmon_pwm:
 368                 switch (attr) {
 369                 case hwmon_pwm_enable:
 370                 case hwmon_pwm_input:
 371                 case hwmon_pwm_freq:
 372                 case hwmon_pwm_auto_channels_temp:
 373                         return 0644;
 374                 default:
 375                         return 0;
 376                 }
 377         default:
 378                 return 0;
 379         }
 380 }
 381
 382 static int max31760_read_string(struct device *dev,
 383                                 enum hwmon_sensor_types type,
 384                                 u32 attr, int channel, const char **str)
 385 {
 386         switch (type) {
 387         case hwmon_temp:
 388                 if (attr != hwmon_temp_label)
 389                         return -EOPNOTSUPP;
 390
 391                 *str = channel ? "local" : "remote";
 392
 393                 return 0;
 394         default:
 395                 return -EOPNOTSUPP;
 396         }
 397 }
 398
 399 static const struct hwmon_ops max31760_hwmon_ops = {
 400         .is_visible = max31760_is_visible,
 401         .read = max31760_read,
 402         .write = max31760_write,
 403         .read_string = max31760_read_string
 404 };
 405
 406 static const struct hwmon_chip_info max31760_chip_info = {
 407         .ops = &max31760_hwmon_ops,
 408         .info = max31760_info,
 409 };
 410
 411 static ssize_t lut_show(struct device *dev,
 412                         struct device_attribute *devattr, char *buf)
 413 {
 414         struct sensor_device_attribute *sda = to_sensor_dev_attr(devattr);
 415         struct max31760_state *state = dev_get_drvdata(dev);
 416         int ret;
 417         unsigned int regval;
 418
 419         ret = regmap_read(state->regmap, REG_LUT(sda->index), &regval);
 420         if (ret)
 421                 return ret;
 422
 423         return sysfs_emit(buf, "%d\n", regval);
 424 }
 425
 426 static ssize_t lut_store(struct device *dev,
 427                          struct device_attribute *devattr,
 428                          const char *buf, size_t count)
 429 {
 430         struct sensor_device_attribute *sda = to_sensor_dev_attr(devattr);
 431         struct max31760_state *state = dev_get_drvdata(dev);
 432         int ret;
 433         u8 pwm;
 434
 435         ret = kstrtou8(buf, 10, &pwm);
 436         if (ret)
 437                 return ret;
 438
 439         ret = regmap_write(state->regmap, REG_LUT(sda->index), pwm);
 440         if (ret)
 441                 return ret;
 442
 443         return count;
 444 }
 445
 446 static ssize_t pwm1_auto_point_temp_hyst_show(struct device *dev,
 447                                               struct device_attribute *attr,
 448                                               char *buf)
 449 {
 450         struct max31760_state *state = dev_get_drvdata(dev);
 451         unsigned int regval;
 452         int ret;
 453
 454         ret = regmap_read(state->regmap, REG_CR1, &regval);
 455         if (ret)
 456                 return ret;
 457
 458         return sysfs_emit(buf, "%d\n", (1 + (int)FIELD_GET(CR1_HYST, regval)) * 2000);
 459 }
 460
 461 static ssize_t pwm1_auto_point_temp_hyst_store(struct device *dev,
 462                                                struct device_attribute *attr,
 463                                                const char *buf,
 464                                                size_t count)
 465 {
 466         struct max31760_state *state = dev_get_drvdata(dev);
 467         unsigned int hyst;
 468         int ret;
 469
 470         ret = kstrtou32(buf, 10, &hyst);
 471         if (ret)
 472                 return ret;
 473
 474         if (hyst < 3000)
 475                 ret = regmap_clear_bits(state->regmap, REG_CR1, CR1_HYST);
 476         else
 477                 ret = regmap_set_bits(state->regmap, REG_CR1, CR1_HYST);
 478
 479         if (ret)
 480                 return ret;
 481
 482         return count;
 483 }
 484
 485 static DEVICE_ATTR_RW(pwm1_auto_point_temp_hyst);
 486
 487 static void max31760_create_lut_nodes(struct max31760_state *state)
 488 {
 489         int i;
 490         struct sensor_device_attribute *sda;
 491         struct lut_attribute *lut;
 492
 493         for (i = 0; i < LUT_SIZE; ++i) {
 494                 lut = &state->lut[i];
 495                 sda = &lut->sda;
 496
 497                 snprintf(lut->name, sizeof(lut->name),
 498                          "pwm1_auto_point%d_pwm", i + 1);
 499
 500                 sda->dev_attr.attr.mode = 0644;
 501                 sda->index = i;
 502                 sda->dev_attr.show = lut_show;
 503                 sda->dev_attr.store = lut_store;
 504                 sda->dev_attr.attr.name = lut->name;
 505
 506                 sysfs_attr_init(&sda->dev_attr.attr);
 507
 508                 state->attrs[i] = &sda->dev_attr.attr;
 509         }
 510
 511         state->attrs[i] = &dev_attr_pwm1_auto_point_temp_hyst.attr;
 512
 513         state->group.attrs = state->attrs;
 514         state->groups[0] = &state->group;
 515 }
 516
 517 static int max31760_probe(struct i2c_client *client)
 518 {
 519         struct device *dev = &client->dev;
 520         struct max31760_state *state;
 521         struct device *hwmon_dev;
 522         int ret;
 523
 524         state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
 525         if (!state)
 526                 return -ENOMEM;
 527
 528         state->regmap = devm_regmap_init_i2c(client, &regmap_config);
 529         if (IS_ERR(state->regmap))
 530                 return dev_err_probe(dev,
 531                                      PTR_ERR(state->regmap),
 532                                      "regmap initialization failed\n");
 533
 534         dev_set_drvdata(dev, state);
 535
 536         /* Set alert output to comparator mode */
 537         ret = regmap_set_bits(state->regmap, REG_CR2, CR2_ALERTS);
 538         if (ret)
 539                 return dev_err_probe(dev, ret, "cannot write register\n");
 540
 541         max31760_create_lut_nodes(state);
 542
 543         hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 544                                                          state,
 545                                                          &max31760_chip_info,
 546                                                          state->groups);
 547
 548         return PTR_ERR_OR_ZERO(hwmon_dev);
 549 }
 550
 551 static const struct of_device_id max31760_of_match[] = {
 552         {.compatible = "adi,max31760"},
 553         { }
 554 };
 555 MODULE_DEVICE_TABLE(of, max31760_of_match);
 556
 557 static const struct i2c_device_id max31760_id[] = {
 558         {"max31760"},
 559         { }
 560 };
 561 MODULE_DEVICE_TABLE(i2c, max31760_id);
 562
 563 static int max31760_suspend(struct device *dev)
 564 {
 565         struct max31760_state *state = dev_get_drvdata(dev);
 566
 567         return regmap_set_bits(state->regmap, REG_CR2, CR2_STBY);
 568 }
 569
 570 static int max31760_resume(struct device *dev)
 571 {
 572         struct max31760_state *state = dev_get_drvdata(dev);
 573
 574         return regmap_clear_bits(state->regmap, REG_CR2, CR2_STBY);
 575 }
 576
 577 static DEFINE_SIMPLE_DEV_PM_OPS(max31760_pm_ops, max31760_suspend,
 578                                 max31760_resume);
 579
 580 static struct i2c_driver max31760_driver = {
 581         .class          = I2C_CLASS_HWMON,
 582         .driver = {
 583                 .name   = "max31760",
 584                 .of_match_table = max31760_of_match,
 585                 .pm = pm_ptr(&max31760_pm_ops)
 586         },
 587         .probe_new      = max31760_probe,
 588         .id_table       = max31760_id
 589 };
 590 module_i2c_driver(max31760_driver);
 591
 592 MODULE_AUTHOR("Ibrahim Tilki <Ibrahim.Tilki@analog.com>");
 593 MODULE_DESCRIPTION("Analog Devices MAX31760 Fan Speed Controller");
 594 MODULE_SOFTDEP("pre: regmap_i2c");
 595 MODULE_VERSION("1.0");
 596 MODULE_LICENSE("GPL");