1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Hwmon client for disk and solid state drives with temperature sensors 4 * Copyright (C) 2019 Zodiac Inflight Innovations 5 * 6 * With input from: 7 * Hwmon client for S.M.A.R.T. hard disk drives with temperature sensors. 8 * (C) 2018 Linus Walleij 9 * 10 * hwmon: Driver for SCSI/ATA temperature sensors 11 * by Constantin Baranov <const@mimas.ru>, submitted September 2009 12 * 13 * This drive supports reporting the temperature of SATA drives. It can be 14 * easily extended to report the temperature of SCSI drives. 15 * 16 * The primary means to read drive temperatures and temperature limits 17 * for ATA drives is the SCT Command Transport feature set as specified in 18 * ATA8-ACS. 19 * It can be used to read the current drive temperature, temperature limits, 20 * and historic minimum and maximum temperatures. The SCT Command Transport 21 * feature set is documented in "AT Attachment 8 - ATA/ATAPI Command Set 22 * (ATA8-ACS)". 23 * 24 * If the SCT Command Transport feature set is not available, drive temperatures 25 * may be readable through SMART attributes. Since SMART attributes are not well 26 * defined, this method is only used as fallback mechanism. 27 * 28 * There are three SMART attributes which may report drive temperatures. 29 * Those are defined as follows (from 30 * http://www.cropel.com/library/smart-attribute-list.aspx). 31 * 32 * 190 Temperature Temperature, monitored by a sensor somewhere inside 33 * the drive. Raw value typicaly holds the actual 34 * temperature (hexadecimal) in its rightmost two digits. 35 * 36 * 194 Temperature Temperature, monitored by a sensor somewhere inside 37 * the drive. Raw value typicaly holds the actual 38 * temperature (hexadecimal) in its rightmost two digits. 39 * 40 * 231 Temperature Temperature, monitored by a sensor somewhere inside 41 * the drive. Raw value typicaly holds the actual 42 * temperature (hexadecimal) in its rightmost two digits. 43 * 44 * Wikipedia defines attributes a bit differently. 45 * 46 * 190 Temperature Value is equal to (100-temp. °C), allowing manufacturer 47 * Difference or to set a minimum threshold which corresponds to a 48 * Airflow maximum temperature. This also follows the convention of 49 * Temperature 100 being a best-case value and lower values being 50 * undesirable. However, some older drives may instead 51 * report raw Temperature (identical to 0xC2) or 52 * Temperature minus 50 here. 53 * 194 Temperature or Indicates the device temperature, if the appropriate 54 * Temperature sensor is fitted. Lowest byte of the raw value contains 55 * Celsius the exact temperature value (Celsius degrees). 56 * 231 Life Left Indicates the approximate SSD life left, in terms of 57 * (SSDs) or program/erase cycles or available reserved blocks. 58 * Temperature A normalized value of 100 represents a new drive, with 59 * a threshold value at 10 indicating a need for 60 * replacement. A value of 0 may mean that the drive is 61 * operating in read-only mode to allow data recovery. 62 * Previously (pre-2010) occasionally used for Drive 63 * Temperature (more typically reported at 0xC2). 64 * 65 * Common denominator is that the first raw byte reports the temperature 66 * in degrees C on almost all drives. Some drives may report a fractional 67 * temperature in the second raw byte. 68 * 69 * Known exceptions (from libatasmart): 70 * - SAMSUNG SV0412H and SAMSUNG SV1204H) report the temperature in 10th 71 * degrees C in the first two raw bytes. 72 * - A few Maxtor drives report an unknown or bad value in attribute 194. 73 * - Certain Apple SSD drives report an unknown value in attribute 190. 74 * Only certain firmware versions are affected. 75 * 76 * Those exceptions affect older ATA drives and are currently ignored. 77 * Also, the second raw byte (possibly reporting the fractional temperature) 78 * is currently ignored. 79 * 80 * Many drives also report temperature limits in additional SMART data raw 81 * bytes. The format of those is not well defined and varies widely. 82 * The driver does not currently attempt to report those limits. 83 * 84 * According to data in smartmontools, attribute 231 is rarely used to report 85 * drive temperatures. At the same time, several drives report SSD life left 86 * in attribute 231, but do not support temperature sensors. For this reason, 87 * attribute 231 is currently ignored. 88 * 89 * Following above definitions, temperatures are reported as follows. 90 * If SCT Command Transport is supported, it is used to read the 91 * temperature and, if available, temperature limits. 92 * - Otherwise, if SMART attribute 194 is supported, it is used to read 93 * the temperature. 94 * - Otherwise, if SMART attribute 190 is supported, it is used to read 95 * the temperature. 96 */ 97 98 #include <linux/ata.h> 99 #include <linux/bits.h> 100 #include <linux/device.h> 101 #include <linux/hwmon.h> 102 #include <linux/kernel.h> 103 #include <linux/list.h> 104 #include <linux/module.h> 105 #include <scsi/scsi_cmnd.h> 106 #include <scsi/scsi_device.h> 107 #include <scsi/scsi_driver.h> 108 #include <scsi/scsi_proto.h> 109 110 struct drivetemp_data { 111 struct list_head list; /* list of instantiated devices */ 112 struct scsi_device *sdev; /* SCSI device */ 113 struct device *dev; /* instantiating device */ 114 struct device *hwdev; /* hardware monitoring device */ 115 u8 smartdata[ATA_SECT_SIZE]; /* local buffer */ 116 int (*get_temp)(struct drivetemp_data *st, u32 attr, long *val); 117 bool have_temp_lowest; /* lowest temp in SCT status */ 118 bool have_temp_highest; /* highest temp in SCT status */ 119 bool have_temp_min; /* have min temp */ 120 bool have_temp_max; /* have max temp */ 121 bool have_temp_lcrit; /* have lower critical limit */ 122 bool have_temp_crit; /* have critical limit */ 123 int temp_min; /* min temp */ 124 int temp_max; /* max temp */ 125 int temp_lcrit; /* lower critical limit */ 126 int temp_crit; /* critical limit */ 127 }; 128 129 static LIST_HEAD(drivetemp_devlist); 130 131 #define ATA_MAX_SMART_ATTRS 30 132 #define SMART_TEMP_PROP_190 190 133 #define SMART_TEMP_PROP_194 194 134 135 #define SCT_STATUS_REQ_ADDR 0xe0 136 #define SCT_STATUS_VERSION_LOW 0 /* log byte offsets */ 137 #define SCT_STATUS_VERSION_HIGH 1 138 #define SCT_STATUS_TEMP 200 139 #define SCT_STATUS_TEMP_LOWEST 201 140 #define SCT_STATUS_TEMP_HIGHEST 202 141 #define SCT_READ_LOG_ADDR 0xe1 142 #define SMART_READ_LOG 0xd5 143 #define SMART_WRITE_LOG 0xd6 144 145 #define INVALID_TEMP 0x80 146 147 #define temp_is_valid(temp) ((temp) != INVALID_TEMP) 148 #define temp_from_sct(temp) (((s8)(temp)) * 1000) 149 150 static inline bool ata_id_smart_supported(u16 *id) 151 { 152 return id[ATA_ID_COMMAND_SET_1] & BIT(0); 153 } 154 155 static inline bool ata_id_smart_enabled(u16 *id) 156 { 157 return id[ATA_ID_CFS_ENABLE_1] & BIT(0); 158 } 159 160 static int drivetemp_scsi_command(struct drivetemp_data *st, 161 u8 ata_command, u8 feature, 162 u8 lba_low, u8 lba_mid, u8 lba_high) 163 { 164 u8 scsi_cmd[MAX_COMMAND_SIZE]; 165 enum req_op op; 166 int err; 167 168 memset(scsi_cmd, 0, sizeof(scsi_cmd)); 169 scsi_cmd[0] = ATA_16; 170 if (ata_command == ATA_CMD_SMART && feature == SMART_WRITE_LOG) { 171 scsi_cmd[1] = (5 << 1); /* PIO Data-out */ 172 /* 173 * No off.line or cc, write to dev, block count in sector count 174 * field. 175 */ 176 scsi_cmd[2] = 0x06; 177 op = REQ_OP_DRV_OUT; 178 } else { 179 scsi_cmd[1] = (4 << 1); /* PIO Data-in */ 180 /* 181 * No off.line or cc, read from dev, block count in sector count 182 * field. 183 */ 184 scsi_cmd[2] = 0x0e; 185 op = REQ_OP_DRV_IN; 186 } 187 scsi_cmd[4] = feature; 188 scsi_cmd[6] = 1; /* 1 sector */ 189 scsi_cmd[8] = lba_low; 190 scsi_cmd[10] = lba_mid; 191 scsi_cmd[12] = lba_high; 192 scsi_cmd[14] = ata_command; 193 194 err = scsi_execute_cmd(st->sdev, scsi_cmd, op, st->smartdata, 195 ATA_SECT_SIZE, 10 * HZ, 5, NULL); 196 if (err > 0) 197 err = -EIO; 198 return err; 199 } 200 201 static int drivetemp_ata_command(struct drivetemp_data *st, u8 feature, 202 u8 select) 203 { 204 return drivetemp_scsi_command(st, ATA_CMD_SMART, feature, select, 205 ATA_SMART_LBAM_PASS, ATA_SMART_LBAH_PASS); 206 } 207 208 static int drivetemp_get_smarttemp(struct drivetemp_data *st, u32 attr, 209 long *temp) 210 { 211 u8 *buf = st->smartdata; 212 bool have_temp = false; 213 u8 temp_raw; 214 u8 csum; 215 int err; 216 int i; 217 218 err = drivetemp_ata_command(st, ATA_SMART_READ_VALUES, 0); 219 if (err) 220 return err; 221 222 /* Checksum the read value table */ 223 csum = 0; 224 for (i = 0; i < ATA_SECT_SIZE; i++) 225 csum += buf[i]; 226 if (csum) { 227 dev_dbg(&st->sdev->sdev_gendev, 228 "checksum error reading SMART values\n"); 229 return -EIO; 230 } 231 232 for (i = 0; i < ATA_MAX_SMART_ATTRS; i++) { 233 u8 *attr = buf + i * 12; 234 int id = attr[2]; 235 236 if (!id) 237 continue; 238 239 if (id == SMART_TEMP_PROP_190) { 240 temp_raw = attr[7]; 241 have_temp = true; 242 } 243 if (id == SMART_TEMP_PROP_194) { 244 temp_raw = attr[7]; 245 have_temp = true; 246 break; 247 } 248 } 249 250 if (have_temp) { 251 *temp = temp_raw * 1000; 252 return 0; 253 } 254 255 return -ENXIO; 256 } 257 258 static int drivetemp_get_scttemp(struct drivetemp_data *st, u32 attr, long *val) 259 { 260 u8 *buf = st->smartdata; 261 int err; 262 263 err = drivetemp_ata_command(st, SMART_READ_LOG, SCT_STATUS_REQ_ADDR); 264 if (err) 265 return err; 266 switch (attr) { 267 case hwmon_temp_input: 268 if (!temp_is_valid(buf[SCT_STATUS_TEMP])) 269 return -ENODATA; 270 *val = temp_from_sct(buf[SCT_STATUS_TEMP]); 271 break; 272 case hwmon_temp_lowest: 273 if (!temp_is_valid(buf[SCT_STATUS_TEMP_LOWEST])) 274 return -ENODATA; 275 *val = temp_from_sct(buf[SCT_STATUS_TEMP_LOWEST]); 276 break; 277 case hwmon_temp_highest: 278 if (!temp_is_valid(buf[SCT_STATUS_TEMP_HIGHEST])) 279 return -ENODATA; 280 *val = temp_from_sct(buf[SCT_STATUS_TEMP_HIGHEST]); 281 break; 282 default: 283 err = -EINVAL; 284 break; 285 } 286 return err; 287 } 288 289 static const char * const sct_avoid_models[] = { 290 /* 291 * These drives will have WRITE FPDMA QUEUED command timeouts and sometimes just 292 * freeze until power-cycled under heavy write loads when their temperature is 293 * getting polled in SCT mode. The SMART mode seems to be fine, though. 294 * 295 * While only the 3 TB model (DT01ACA3) was actually caught exhibiting the 296 * problem let's play safe here to avoid data corruption and ban the whole 297 * DT01ACAx family. 298 299 * The models from this array are prefix-matched. 300 */ 301 "TOSHIBA DT01ACA", 302 }; 303 304 static bool drivetemp_sct_avoid(struct drivetemp_data *st) 305 { 306 struct scsi_device *sdev = st->sdev; 307 unsigned int ctr; 308 309 /* 310 * The "model" field contains just the raw SCSI INQUIRY response 311 * "product identification" field, which has a width of 16 bytes. 312 * This field is space-filled and NUL-terminated. 313 */ 314 for (ctr = 0; ctr < ARRAY_SIZE(sct_avoid_models); ctr++) 315 if (!strncmp(sdev->model, sct_avoid_models[ctr], 316 strlen(sct_avoid_models[ctr]))) 317 return true; 318 319 return false; 320 } 321 322 static int drivetemp_identify_sata(struct drivetemp_data *st) 323 { 324 struct scsi_device *sdev = st->sdev; 325 u8 *buf = st->smartdata; 326 struct scsi_vpd *vpd; 327 bool is_ata, is_sata; 328 bool have_sct_data_table; 329 bool have_sct_temp; 330 bool have_smart; 331 bool have_sct; 332 u16 *ata_id; 333 u16 version; 334 long temp; 335 int err; 336 337 /* SCSI-ATA Translation present? */ 338 rcu_read_lock(); 339 vpd = rcu_dereference(sdev->vpd_pg89); 340 341 /* 342 * Verify that ATA IDENTIFY DEVICE data is included in ATA Information 343 * VPD and that the drive implements the SATA protocol. 344 */ 345 if (!vpd || vpd->len < 572 || vpd->data[56] != ATA_CMD_ID_ATA || 346 vpd->data[36] != 0x34) { 347 rcu_read_unlock(); 348 return -ENODEV; 349 } 350 ata_id = (u16 *)&vpd->data[60]; 351 is_ata = ata_id_is_ata(ata_id); 352 is_sata = ata_id_is_sata(ata_id); 353 have_sct = ata_id_sct_supported(ata_id); 354 have_sct_data_table = ata_id_sct_data_tables(ata_id); 355 have_smart = ata_id_smart_supported(ata_id) && 356 ata_id_smart_enabled(ata_id); 357 358 rcu_read_unlock(); 359 360 /* bail out if this is not a SATA device */ 361 if (!is_ata || !is_sata) 362 return -ENODEV; 363 364 if (have_sct && drivetemp_sct_avoid(st)) { 365 dev_notice(&sdev->sdev_gendev, 366 "will avoid using SCT for temperature monitoring\n"); 367 have_sct = false; 368 } 369 370 if (!have_sct) 371 goto skip_sct; 372 373 err = drivetemp_ata_command(st, SMART_READ_LOG, SCT_STATUS_REQ_ADDR); 374 if (err) 375 goto skip_sct; 376 377 version = (buf[SCT_STATUS_VERSION_HIGH] << 8) | 378 buf[SCT_STATUS_VERSION_LOW]; 379 if (version != 2 && version != 3) 380 goto skip_sct; 381 382 have_sct_temp = temp_is_valid(buf[SCT_STATUS_TEMP]); 383 if (!have_sct_temp) 384 goto skip_sct; 385 386 st->have_temp_lowest = temp_is_valid(buf[SCT_STATUS_TEMP_LOWEST]); 387 st->have_temp_highest = temp_is_valid(buf[SCT_STATUS_TEMP_HIGHEST]); 388 389 if (!have_sct_data_table) 390 goto skip_sct_data; 391 392 /* Request and read temperature history table */ 393 memset(buf, '\0', sizeof(st->smartdata)); 394 buf[0] = 5; /* data table command */ 395 buf[2] = 1; /* read table */ 396 buf[4] = 2; /* temperature history table */ 397 398 err = drivetemp_ata_command(st, SMART_WRITE_LOG, SCT_STATUS_REQ_ADDR); 399 if (err) 400 goto skip_sct_data; 401 402 err = drivetemp_ata_command(st, SMART_READ_LOG, SCT_READ_LOG_ADDR); 403 if (err) 404 goto skip_sct_data; 405 406 /* 407 * Temperature limits per AT Attachment 8 - 408 * ATA/ATAPI Command Set (ATA8-ACS) 409 */ 410 st->have_temp_max = temp_is_valid(buf[6]); 411 st->have_temp_crit = temp_is_valid(buf[7]); 412 st->have_temp_min = temp_is_valid(buf[8]); 413 st->have_temp_lcrit = temp_is_valid(buf[9]); 414 415 st->temp_max = temp_from_sct(buf[6]); 416 st->temp_crit = temp_from_sct(buf[7]); 417 st->temp_min = temp_from_sct(buf[8]); 418 st->temp_lcrit = temp_from_sct(buf[9]); 419 420 skip_sct_data: 421 if (have_sct_temp) { 422 st->get_temp = drivetemp_get_scttemp; 423 return 0; 424 } 425 skip_sct: 426 if (!have_smart) 427 return -ENODEV; 428 st->get_temp = drivetemp_get_smarttemp; 429 return drivetemp_get_smarttemp(st, hwmon_temp_input, &temp); 430 } 431 432 static int drivetemp_identify(struct drivetemp_data *st) 433 { 434 struct scsi_device *sdev = st->sdev; 435 436 /* Bail out immediately if there is no inquiry data */ 437 if (!sdev->inquiry || sdev->inquiry_len < 16) 438 return -ENODEV; 439 440 /* Disk device? */ 441 if (sdev->type != TYPE_DISK && sdev->type != TYPE_ZBC) 442 return -ENODEV; 443 444 return drivetemp_identify_sata(st); 445 } 446 447 static int drivetemp_read(struct device *dev, enum hwmon_sensor_types type, 448 u32 attr, int channel, long *val) 449 { 450 struct drivetemp_data *st = dev_get_drvdata(dev); 451 int err = 0; 452 453 if (type != hwmon_temp) 454 return -EINVAL; 455 456 switch (attr) { 457 case hwmon_temp_input: 458 case hwmon_temp_lowest: 459 case hwmon_temp_highest: 460 err = st->get_temp(st, attr, val); 461 break; 462 case hwmon_temp_lcrit: 463 *val = st->temp_lcrit; 464 break; 465 case hwmon_temp_min: 466 *val = st->temp_min; 467 break; 468 case hwmon_temp_max: 469 *val = st->temp_max; 470 break; 471 case hwmon_temp_crit: 472 *val = st->temp_crit; 473 break; 474 default: 475 err = -EINVAL; 476 break; 477 } 478 return err; 479 } 480 481 static umode_t drivetemp_is_visible(const void *data, 482 enum hwmon_sensor_types type, 483 u32 attr, int channel) 484 { 485 const struct drivetemp_data *st = data; 486 487 switch (type) { 488 case hwmon_temp: 489 switch (attr) { 490 case hwmon_temp_input: 491 return 0444; 492 case hwmon_temp_lowest: 493 if (st->have_temp_lowest) 494 return 0444; 495 break; 496 case hwmon_temp_highest: 497 if (st->have_temp_highest) 498 return 0444; 499 break; 500 case hwmon_temp_min: 501 if (st->have_temp_min) 502 return 0444; 503 break; 504 case hwmon_temp_max: 505 if (st->have_temp_max) 506 return 0444; 507 break; 508 case hwmon_temp_lcrit: 509 if (st->have_temp_lcrit) 510 return 0444; 511 break; 512 case hwmon_temp_crit: 513 if (st->have_temp_crit) 514 return 0444; 515 break; 516 default: 517 break; 518 } 519 break; 520 default: 521 break; 522 } 523 return 0; 524 } 525 526 static const struct hwmon_channel_info * const drivetemp_info[] = { 527 HWMON_CHANNEL_INFO(chip, 528 HWMON_C_REGISTER_TZ), 529 HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | 530 HWMON_T_LOWEST | HWMON_T_HIGHEST | 531 HWMON_T_MIN | HWMON_T_MAX | 532 HWMON_T_LCRIT | HWMON_T_CRIT), 533 NULL 534 }; 535 536 static const struct hwmon_ops drivetemp_ops = { 537 .is_visible = drivetemp_is_visible, 538 .read = drivetemp_read, 539 }; 540 541 static const struct hwmon_chip_info drivetemp_chip_info = { 542 .ops = &drivetemp_ops, 543 .info = drivetemp_info, 544 }; 545 546 /* 547 * The device argument points to sdev->sdev_dev. Its parent is 548 * sdev->sdev_gendev, which we can use to get the scsi_device pointer. 549 */ 550 static int drivetemp_add(struct device *dev) 551 { 552 struct scsi_device *sdev = to_scsi_device(dev->parent); 553 struct drivetemp_data *st; 554 int err; 555 556 st = kzalloc_obj(*st); 557 if (!st) 558 return -ENOMEM; 559 560 st->sdev = sdev; 561 st->dev = dev; 562 563 if (drivetemp_identify(st)) { 564 err = -ENODEV; 565 goto abort; 566 } 567 568 st->hwdev = hwmon_device_register_with_info(dev->parent, "drivetemp", 569 st, &drivetemp_chip_info, 570 NULL); 571 if (IS_ERR(st->hwdev)) { 572 err = PTR_ERR(st->hwdev); 573 goto abort; 574 } 575 576 list_add(&st->list, &drivetemp_devlist); 577 return 0; 578 579 abort: 580 kfree(st); 581 return err; 582 } 583 584 static void drivetemp_remove(struct device *dev) 585 { 586 struct drivetemp_data *st, *tmp; 587 588 list_for_each_entry_safe(st, tmp, &drivetemp_devlist, list) { 589 if (st->dev == dev) { 590 list_del(&st->list); 591 hwmon_device_unregister(st->hwdev); 592 kfree(st); 593 break; 594 } 595 } 596 } 597 598 static struct class_interface drivetemp_interface = { 599 .add_dev = drivetemp_add, 600 .remove_dev = drivetemp_remove, 601 }; 602 603 static int __init drivetemp_init(void) 604 { 605 return scsi_register_interface(&drivetemp_interface); 606 } 607 608 static void __exit drivetemp_exit(void) 609 { 610 scsi_unregister_interface(&drivetemp_interface); 611 } 612 613 module_init(drivetemp_init); 614 module_exit(drivetemp_exit); 615 616 MODULE_AUTHOR("Guenter Roeck <linus@roeck-us.net>"); 617 MODULE_DESCRIPTION("Hard drive temperature monitor"); 618 MODULE_LICENSE("GPL"); 619 MODULE_ALIAS("platform:drivetemp"); 620