1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * emc2103.c - Support for SMSC EMC2103 4 * Copyright (c) 2010 SMSC 5 */ 6 7 #include <linux/module.h> 8 #include <linux/init.h> 9 #include <linux/slab.h> 10 #include <linux/jiffies.h> 11 #include <linux/i2c.h> 12 #include <linux/hwmon.h> 13 #include <linux/hwmon-sysfs.h> 14 #include <linux/err.h> 15 #include <linux/mutex.h> 16 17 /* Addresses scanned */ 18 static const unsigned short normal_i2c[] = { 0x2E, I2C_CLIENT_END }; 19 20 static const u8 REG_TEMP[4] = { 0x00, 0x02, 0x04, 0x06 }; 21 static const u8 REG_TEMP_MIN[4] = { 0x3c, 0x38, 0x39, 0x3a }; 22 static const u8 REG_TEMP_MAX[4] = { 0x34, 0x30, 0x31, 0x32 }; 23 24 #define REG_CONF1 0x20 25 #define REG_TEMP_MAX_ALARM 0x24 26 #define REG_TEMP_MIN_ALARM 0x25 27 #define REG_FAN_CONF1 0x42 28 #define REG_FAN_TARGET_LO 0x4c 29 #define REG_FAN_TARGET_HI 0x4d 30 #define REG_FAN_TACH_HI 0x4e 31 #define REG_FAN_TACH_LO 0x4f 32 #define REG_PRODUCT_ID 0xfd 33 #define REG_MFG_ID 0xfe 34 35 /* equation 4 from datasheet: rpm = (3932160 * multipler) / count */ 36 #define FAN_RPM_FACTOR 3932160 37 38 /* 39 * 2103-2 and 2103-4's 3rd temperature sensor can be connected to two diodes 40 * in anti-parallel mode, and in this configuration both can be read 41 * independently (so we have 4 temperature inputs). The device can't 42 * detect if it's connected in this mode, so we have to manually enable 43 * it. Default is to leave the device in the state it's already in (-1). 44 * This parameter allows APD mode to be optionally forced on or off 45 */ 46 static int apd = -1; 47 module_param(apd, bint, 0); 48 MODULE_PARM_DESC(apd, "Set to zero to disable anti-parallel diode mode"); 49 50 struct temperature { 51 s8 degrees; 52 u8 fraction; /* 0-7 multiples of 0.125 */ 53 }; 54 55 struct emc2103_data { 56 struct i2c_client *client; 57 const struct attribute_group *groups[4]; 58 struct mutex update_lock; 59 bool valid; /* registers are valid */ 60 bool fan_rpm_control; 61 int temp_count; /* num of temp sensors */ 62 unsigned long last_updated; /* in jiffies */ 63 struct temperature temp[4]; /* internal + 3 external */ 64 s8 temp_min[4]; /* no fractional part */ 65 s8 temp_max[4]; /* no fractional part */ 66 u8 temp_min_alarm; 67 u8 temp_max_alarm; 68 u8 fan_multiplier; 69 u16 fan_tach; 70 u16 fan_target; 71 }; 72 73 static int read_u8_from_i2c(struct i2c_client *client, u8 i2c_reg, u8 *output) 74 { 75 int status = i2c_smbus_read_byte_data(client, i2c_reg); 76 if (status < 0) { 77 dev_warn(&client->dev, "reg 0x%02x, err %d\n", 78 i2c_reg, status); 79 } else { 80 *output = status; 81 } 82 return status; 83 } 84 85 static void read_temp_from_i2c(struct i2c_client *client, u8 i2c_reg, 86 struct temperature *temp) 87 { 88 u8 degrees, fractional; 89 90 if (read_u8_from_i2c(client, i2c_reg, °rees) < 0) 91 return; 92 93 if (read_u8_from_i2c(client, i2c_reg + 1, &fractional) < 0) 94 return; 95 96 temp->degrees = degrees; 97 temp->fraction = (fractional & 0xe0) >> 5; 98 } 99 100 static void read_fan_from_i2c(struct i2c_client *client, u16 *output, 101 u8 hi_addr, u8 lo_addr) 102 { 103 u8 high_byte, lo_byte; 104 105 if (read_u8_from_i2c(client, hi_addr, &high_byte) < 0) 106 return; 107 108 if (read_u8_from_i2c(client, lo_addr, &lo_byte) < 0) 109 return; 110 111 *output = ((u16)high_byte << 5) | (lo_byte >> 3); 112 } 113 114 static void write_fan_target_to_i2c(struct i2c_client *client, u16 new_target) 115 { 116 u8 high_byte = (new_target & 0x1fe0) >> 5; 117 u8 low_byte = (new_target & 0x001f) << 3; 118 i2c_smbus_write_byte_data(client, REG_FAN_TARGET_LO, low_byte); 119 i2c_smbus_write_byte_data(client, REG_FAN_TARGET_HI, high_byte); 120 } 121 122 static void read_fan_config_from_i2c(struct i2c_client *client) 123 124 { 125 struct emc2103_data *data = i2c_get_clientdata(client); 126 u8 conf1; 127 128 if (read_u8_from_i2c(client, REG_FAN_CONF1, &conf1) < 0) 129 return; 130 131 data->fan_multiplier = 1 << ((conf1 & 0x60) >> 5); 132 data->fan_rpm_control = (conf1 & 0x80) != 0; 133 } 134 135 static struct emc2103_data *emc2103_update_device(struct device *dev) 136 { 137 struct emc2103_data *data = dev_get_drvdata(dev); 138 struct i2c_client *client = data->client; 139 140 mutex_lock(&data->update_lock); 141 142 if (time_after(jiffies, data->last_updated + HZ + HZ / 2) 143 || !data->valid) { 144 int i; 145 146 for (i = 0; i < data->temp_count; i++) { 147 read_temp_from_i2c(client, REG_TEMP[i], &data->temp[i]); 148 read_u8_from_i2c(client, REG_TEMP_MIN[i], 149 &data->temp_min[i]); 150 read_u8_from_i2c(client, REG_TEMP_MAX[i], 151 &data->temp_max[i]); 152 } 153 154 read_u8_from_i2c(client, REG_TEMP_MIN_ALARM, 155 &data->temp_min_alarm); 156 read_u8_from_i2c(client, REG_TEMP_MAX_ALARM, 157 &data->temp_max_alarm); 158 159 read_fan_from_i2c(client, &data->fan_tach, 160 REG_FAN_TACH_HI, REG_FAN_TACH_LO); 161 read_fan_from_i2c(client, &data->fan_target, 162 REG_FAN_TARGET_HI, REG_FAN_TARGET_LO); 163 read_fan_config_from_i2c(client); 164 165 data->last_updated = jiffies; 166 data->valid = true; 167 } 168 169 mutex_unlock(&data->update_lock); 170 171 return data; 172 } 173 174 static ssize_t 175 temp_show(struct device *dev, struct device_attribute *da, char *buf) 176 { 177 int nr = to_sensor_dev_attr(da)->index; 178 struct emc2103_data *data = emc2103_update_device(dev); 179 int millidegrees = data->temp[nr].degrees * 1000 180 + data->temp[nr].fraction * 125; 181 return sprintf(buf, "%d\n", millidegrees); 182 } 183 184 static ssize_t 185 temp_min_show(struct device *dev, struct device_attribute *da, char *buf) 186 { 187 int nr = to_sensor_dev_attr(da)->index; 188 struct emc2103_data *data = emc2103_update_device(dev); 189 int millidegrees = data->temp_min[nr] * 1000; 190 return sprintf(buf, "%d\n", millidegrees); 191 } 192 193 static ssize_t 194 temp_max_show(struct device *dev, struct device_attribute *da, char *buf) 195 { 196 int nr = to_sensor_dev_attr(da)->index; 197 struct emc2103_data *data = emc2103_update_device(dev); 198 int millidegrees = data->temp_max[nr] * 1000; 199 return sprintf(buf, "%d\n", millidegrees); 200 } 201 202 static ssize_t 203 temp_fault_show(struct device *dev, struct device_attribute *da, char *buf) 204 { 205 int nr = to_sensor_dev_attr(da)->index; 206 struct emc2103_data *data = emc2103_update_device(dev); 207 bool fault = (data->temp[nr].degrees == -128); 208 return sprintf(buf, "%d\n", fault ? 1 : 0); 209 } 210 211 static ssize_t 212 temp_min_alarm_show(struct device *dev, struct device_attribute *da, 213 char *buf) 214 { 215 int nr = to_sensor_dev_attr(da)->index; 216 struct emc2103_data *data = emc2103_update_device(dev); 217 bool alarm = data->temp_min_alarm & (1 << nr); 218 return sprintf(buf, "%d\n", alarm ? 1 : 0); 219 } 220 221 static ssize_t 222 temp_max_alarm_show(struct device *dev, struct device_attribute *da, 223 char *buf) 224 { 225 int nr = to_sensor_dev_attr(da)->index; 226 struct emc2103_data *data = emc2103_update_device(dev); 227 bool alarm = data->temp_max_alarm & (1 << nr); 228 return sprintf(buf, "%d\n", alarm ? 1 : 0); 229 } 230 231 static ssize_t temp_min_store(struct device *dev, struct device_attribute *da, 232 const char *buf, size_t count) 233 { 234 int nr = to_sensor_dev_attr(da)->index; 235 struct emc2103_data *data = dev_get_drvdata(dev); 236 struct i2c_client *client = data->client; 237 long val; 238 239 int result = kstrtol(buf, 10, &val); 240 if (result < 0) 241 return result; 242 243 val = DIV_ROUND_CLOSEST(clamp_val(val, -63000, 127000), 1000); 244 245 mutex_lock(&data->update_lock); 246 data->temp_min[nr] = val; 247 i2c_smbus_write_byte_data(client, REG_TEMP_MIN[nr], val); 248 mutex_unlock(&data->update_lock); 249 250 return count; 251 } 252 253 static ssize_t temp_max_store(struct device *dev, struct device_attribute *da, 254 const char *buf, size_t count) 255 { 256 int nr = to_sensor_dev_attr(da)->index; 257 struct emc2103_data *data = dev_get_drvdata(dev); 258 struct i2c_client *client = data->client; 259 long val; 260 261 int result = kstrtol(buf, 10, &val); 262 if (result < 0) 263 return result; 264 265 val = DIV_ROUND_CLOSEST(clamp_val(val, -63000, 127000), 1000); 266 267 mutex_lock(&data->update_lock); 268 data->temp_max[nr] = val; 269 i2c_smbus_write_byte_data(client, REG_TEMP_MAX[nr], val); 270 mutex_unlock(&data->update_lock); 271 272 return count; 273 } 274 275 static ssize_t 276 fan1_input_show(struct device *dev, struct device_attribute *da, char *buf) 277 { 278 struct emc2103_data *data = emc2103_update_device(dev); 279 int rpm = 0; 280 if (data->fan_tach != 0) 281 rpm = (FAN_RPM_FACTOR * data->fan_multiplier) / data->fan_tach; 282 return sprintf(buf, "%d\n", rpm); 283 } 284 285 static ssize_t 286 fan1_div_show(struct device *dev, struct device_attribute *da, char *buf) 287 { 288 struct emc2103_data *data = emc2103_update_device(dev); 289 int fan_div = 8 / data->fan_multiplier; 290 return sprintf(buf, "%d\n", fan_div); 291 } 292 293 /* 294 * Note: we also update the fan target here, because its value is 295 * determined in part by the fan clock divider. This follows the principle 296 * of least surprise; the user doesn't expect the fan target to change just 297 * because the divider changed. 298 */ 299 static ssize_t fan1_div_store(struct device *dev, struct device_attribute *da, 300 const char *buf, size_t count) 301 { 302 struct emc2103_data *data = emc2103_update_device(dev); 303 struct i2c_client *client = data->client; 304 int new_range_bits, old_div = 8 / data->fan_multiplier; 305 long new_div; 306 307 int status = kstrtol(buf, 10, &new_div); 308 if (status < 0) 309 return status; 310 311 if (new_div == old_div) /* No change */ 312 return count; 313 314 switch (new_div) { 315 case 1: 316 new_range_bits = 3; 317 break; 318 case 2: 319 new_range_bits = 2; 320 break; 321 case 4: 322 new_range_bits = 1; 323 break; 324 case 8: 325 new_range_bits = 0; 326 break; 327 default: 328 return -EINVAL; 329 } 330 331 mutex_lock(&data->update_lock); 332 333 status = i2c_smbus_read_byte_data(client, REG_FAN_CONF1); 334 if (status < 0) { 335 dev_dbg(&client->dev, "reg 0x%02x, err %d\n", 336 REG_FAN_CONF1, status); 337 mutex_unlock(&data->update_lock); 338 return status; 339 } 340 status &= 0x9F; 341 status |= (new_range_bits << 5); 342 i2c_smbus_write_byte_data(client, REG_FAN_CONF1, status); 343 344 data->fan_multiplier = 8 / new_div; 345 346 /* update fan target if high byte is not disabled */ 347 if ((data->fan_target & 0x1fe0) != 0x1fe0) { 348 u16 new_target = (data->fan_target * old_div) / new_div; 349 data->fan_target = min(new_target, (u16)0x1fff); 350 write_fan_target_to_i2c(client, data->fan_target); 351 } 352 353 /* invalidate data to force re-read from hardware */ 354 data->valid = false; 355 356 mutex_unlock(&data->update_lock); 357 return count; 358 } 359 360 static ssize_t 361 fan1_target_show(struct device *dev, struct device_attribute *da, char *buf) 362 { 363 struct emc2103_data *data = emc2103_update_device(dev); 364 int rpm = 0; 365 366 /* high byte of 0xff indicates disabled so return 0 */ 367 if ((data->fan_target != 0) && ((data->fan_target & 0x1fe0) != 0x1fe0)) 368 rpm = (FAN_RPM_FACTOR * data->fan_multiplier) 369 / data->fan_target; 370 371 return sprintf(buf, "%d\n", rpm); 372 } 373 374 static ssize_t fan1_target_store(struct device *dev, 375 struct device_attribute *da, const char *buf, 376 size_t count) 377 { 378 struct emc2103_data *data = emc2103_update_device(dev); 379 struct i2c_client *client = data->client; 380 unsigned long rpm_target; 381 382 int result = kstrtoul(buf, 10, &rpm_target); 383 if (result < 0) 384 return result; 385 386 /* Datasheet states 16384 as maximum RPM target (table 3.2) */ 387 rpm_target = clamp_val(rpm_target, 0, 16384); 388 389 mutex_lock(&data->update_lock); 390 391 if (rpm_target == 0) 392 data->fan_target = 0x1fff; 393 else 394 data->fan_target = clamp_val( 395 (FAN_RPM_FACTOR * data->fan_multiplier) / rpm_target, 396 0, 0x1fff); 397 398 write_fan_target_to_i2c(client, data->fan_target); 399 400 mutex_unlock(&data->update_lock); 401 return count; 402 } 403 404 static ssize_t 405 fan1_fault_show(struct device *dev, struct device_attribute *da, char *buf) 406 { 407 struct emc2103_data *data = emc2103_update_device(dev); 408 bool fault = ((data->fan_tach & 0x1fe0) == 0x1fe0); 409 return sprintf(buf, "%d\n", fault ? 1 : 0); 410 } 411 412 static ssize_t 413 pwm1_enable_show(struct device *dev, struct device_attribute *da, char *buf) 414 { 415 struct emc2103_data *data = emc2103_update_device(dev); 416 return sprintf(buf, "%d\n", data->fan_rpm_control ? 3 : 0); 417 } 418 419 static ssize_t pwm1_enable_store(struct device *dev, 420 struct device_attribute *da, const char *buf, 421 size_t count) 422 { 423 struct emc2103_data *data = dev_get_drvdata(dev); 424 struct i2c_client *client = data->client; 425 long new_value; 426 u8 conf_reg; 427 428 int result = kstrtol(buf, 10, &new_value); 429 if (result < 0) 430 return result; 431 432 mutex_lock(&data->update_lock); 433 switch (new_value) { 434 case 0: 435 data->fan_rpm_control = false; 436 break; 437 case 3: 438 data->fan_rpm_control = true; 439 break; 440 default: 441 count = -EINVAL; 442 goto err; 443 } 444 445 result = read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg); 446 if (result < 0) { 447 count = result; 448 goto err; 449 } 450 451 if (data->fan_rpm_control) 452 conf_reg |= 0x80; 453 else 454 conf_reg &= ~0x80; 455 456 i2c_smbus_write_byte_data(client, REG_FAN_CONF1, conf_reg); 457 err: 458 mutex_unlock(&data->update_lock); 459 return count; 460 } 461 462 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0); 463 static SENSOR_DEVICE_ATTR_RW(temp1_min, temp_min, 0); 464 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0); 465 static SENSOR_DEVICE_ATTR_RO(temp1_fault, temp_fault, 0); 466 static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, temp_min_alarm, 0); 467 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, temp_max_alarm, 0); 468 469 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1); 470 static SENSOR_DEVICE_ATTR_RW(temp2_min, temp_min, 1); 471 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1); 472 static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp_fault, 1); 473 static SENSOR_DEVICE_ATTR_RO(temp2_min_alarm, temp_min_alarm, 1); 474 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, temp_max_alarm, 1); 475 476 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2); 477 static SENSOR_DEVICE_ATTR_RW(temp3_min, temp_min, 2); 478 static SENSOR_DEVICE_ATTR_RW(temp3_max, temp_max, 2); 479 static SENSOR_DEVICE_ATTR_RO(temp3_fault, temp_fault, 2); 480 static SENSOR_DEVICE_ATTR_RO(temp3_min_alarm, temp_min_alarm, 2); 481 static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, temp_max_alarm, 2); 482 483 static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3); 484 static SENSOR_DEVICE_ATTR_RW(temp4_min, temp_min, 3); 485 static SENSOR_DEVICE_ATTR_RW(temp4_max, temp_max, 3); 486 static SENSOR_DEVICE_ATTR_RO(temp4_fault, temp_fault, 3); 487 static SENSOR_DEVICE_ATTR_RO(temp4_min_alarm, temp_min_alarm, 3); 488 static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, temp_max_alarm, 3); 489 490 static DEVICE_ATTR_RO(fan1_input); 491 static DEVICE_ATTR_RW(fan1_div); 492 static DEVICE_ATTR_RW(fan1_target); 493 static DEVICE_ATTR_RO(fan1_fault); 494 495 static DEVICE_ATTR_RW(pwm1_enable); 496 497 /* sensors present on all models */ 498 static struct attribute *emc2103_attributes[] = { 499 &sensor_dev_attr_temp1_input.dev_attr.attr, 500 &sensor_dev_attr_temp1_min.dev_attr.attr, 501 &sensor_dev_attr_temp1_max.dev_attr.attr, 502 &sensor_dev_attr_temp1_fault.dev_attr.attr, 503 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr, 504 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 505 &sensor_dev_attr_temp2_input.dev_attr.attr, 506 &sensor_dev_attr_temp2_min.dev_attr.attr, 507 &sensor_dev_attr_temp2_max.dev_attr.attr, 508 &sensor_dev_attr_temp2_fault.dev_attr.attr, 509 &sensor_dev_attr_temp2_min_alarm.dev_attr.attr, 510 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 511 &dev_attr_fan1_input.attr, 512 &dev_attr_fan1_div.attr, 513 &dev_attr_fan1_target.attr, 514 &dev_attr_fan1_fault.attr, 515 &dev_attr_pwm1_enable.attr, 516 NULL 517 }; 518 519 /* extra temperature sensors only present on 2103-2 and 2103-4 */ 520 static struct attribute *emc2103_attributes_temp3[] = { 521 &sensor_dev_attr_temp3_input.dev_attr.attr, 522 &sensor_dev_attr_temp3_min.dev_attr.attr, 523 &sensor_dev_attr_temp3_max.dev_attr.attr, 524 &sensor_dev_attr_temp3_fault.dev_attr.attr, 525 &sensor_dev_attr_temp3_min_alarm.dev_attr.attr, 526 &sensor_dev_attr_temp3_max_alarm.dev_attr.attr, 527 NULL 528 }; 529 530 /* extra temperature sensors only present on 2103-2 and 2103-4 in APD mode */ 531 static struct attribute *emc2103_attributes_temp4[] = { 532 &sensor_dev_attr_temp4_input.dev_attr.attr, 533 &sensor_dev_attr_temp4_min.dev_attr.attr, 534 &sensor_dev_attr_temp4_max.dev_attr.attr, 535 &sensor_dev_attr_temp4_fault.dev_attr.attr, 536 &sensor_dev_attr_temp4_min_alarm.dev_attr.attr, 537 &sensor_dev_attr_temp4_max_alarm.dev_attr.attr, 538 NULL 539 }; 540 541 static const struct attribute_group emc2103_group = { 542 .attrs = emc2103_attributes, 543 }; 544 545 static const struct attribute_group emc2103_temp3_group = { 546 .attrs = emc2103_attributes_temp3, 547 }; 548 549 static const struct attribute_group emc2103_temp4_group = { 550 .attrs = emc2103_attributes_temp4, 551 }; 552 553 static int 554 emc2103_probe(struct i2c_client *client) 555 { 556 struct emc2103_data *data; 557 struct device *hwmon_dev; 558 int status, idx = 0; 559 560 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 561 return -EIO; 562 563 data = devm_kzalloc(&client->dev, sizeof(struct emc2103_data), 564 GFP_KERNEL); 565 if (!data) 566 return -ENOMEM; 567 568 i2c_set_clientdata(client, data); 569 data->client = client; 570 mutex_init(&data->update_lock); 571 572 /* 2103-2 and 2103-4 have 3 external diodes, 2103-1 has 1 */ 573 status = i2c_smbus_read_byte_data(client, REG_PRODUCT_ID); 574 if (status == 0x24) { 575 /* 2103-1 only has 1 external diode */ 576 data->temp_count = 2; 577 } else { 578 /* 2103-2 and 2103-4 have 3 or 4 external diodes */ 579 status = i2c_smbus_read_byte_data(client, REG_CONF1); 580 if (status < 0) { 581 dev_dbg(&client->dev, "reg 0x%02x, err %d\n", REG_CONF1, 582 status); 583 return status; 584 } 585 586 /* detect current state of hardware */ 587 data->temp_count = (status & 0x01) ? 4 : 3; 588 589 /* force APD state if module parameter is set */ 590 if (apd == 0) { 591 /* force APD mode off */ 592 data->temp_count = 3; 593 status &= ~(0x01); 594 i2c_smbus_write_byte_data(client, REG_CONF1, status); 595 } else if (apd == 1) { 596 /* force APD mode on */ 597 data->temp_count = 4; 598 status |= 0x01; 599 i2c_smbus_write_byte_data(client, REG_CONF1, status); 600 } 601 } 602 603 /* sysfs hooks */ 604 data->groups[idx++] = &emc2103_group; 605 if (data->temp_count >= 3) 606 data->groups[idx++] = &emc2103_temp3_group; 607 if (data->temp_count == 4) 608 data->groups[idx++] = &emc2103_temp4_group; 609 610 hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev, 611 client->name, data, 612 data->groups); 613 if (IS_ERR(hwmon_dev)) 614 return PTR_ERR(hwmon_dev); 615 616 dev_info(&client->dev, "%s: sensor '%s'\n", 617 dev_name(hwmon_dev), client->name); 618 619 return 0; 620 } 621 622 static const struct i2c_device_id emc2103_ids[] = { 623 { "emc2103" }, 624 { /* LIST END */ } 625 }; 626 MODULE_DEVICE_TABLE(i2c, emc2103_ids); 627 628 /* Return 0 if detection is successful, -ENODEV otherwise */ 629 static int 630 emc2103_detect(struct i2c_client *new_client, struct i2c_board_info *info) 631 { 632 struct i2c_adapter *adapter = new_client->adapter; 633 int manufacturer, product; 634 635 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 636 return -ENODEV; 637 638 manufacturer = i2c_smbus_read_byte_data(new_client, REG_MFG_ID); 639 if (manufacturer != 0x5D) 640 return -ENODEV; 641 642 product = i2c_smbus_read_byte_data(new_client, REG_PRODUCT_ID); 643 if ((product != 0x24) && (product != 0x26)) 644 return -ENODEV; 645 646 strscpy(info->type, "emc2103", I2C_NAME_SIZE); 647 648 return 0; 649 } 650 651 static struct i2c_driver emc2103_driver = { 652 .class = I2C_CLASS_HWMON, 653 .driver = { 654 .name = "emc2103", 655 }, 656 .probe = emc2103_probe, 657 .id_table = emc2103_ids, 658 .detect = emc2103_detect, 659 .address_list = normal_i2c, 660 }; 661 662 module_i2c_driver(emc2103_driver); 663 664 MODULE_AUTHOR("Steve Glendinning <steve.glendinning@shawell.net>"); 665 MODULE_DESCRIPTION("SMSC EMC2103 hwmon driver"); 666 MODULE_LICENSE("GPL"); 667