1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * max6639.c - Support for Maxim MAX6639 4 * 5 * 2-Channel Temperature Monitor with Dual PWM Fan-Speed Controller 6 * 7 * Copyright (C) 2010, 2011 Roland Stigge <stigge@antcom.de> 8 * 9 * based on the initial MAX6639 support from semptian.net 10 * by He Changqing <hechangqing@semptian.com> 11 */ 12 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/slab.h> 16 #include <linux/jiffies.h> 17 #include <linux/i2c.h> 18 #include <linux/hwmon.h> 19 #include <linux/hwmon-sysfs.h> 20 #include <linux/err.h> 21 #include <linux/mutex.h> 22 #include <linux/platform_data/max6639.h> 23 24 /* Addresses to scan */ 25 static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END }; 26 27 /* The MAX6639 registers, valid channel numbers: 0, 1 */ 28 #define MAX6639_REG_TEMP(ch) (0x00 + (ch)) 29 #define MAX6639_REG_STATUS 0x02 30 #define MAX6639_REG_OUTPUT_MASK 0x03 31 #define MAX6639_REG_GCONFIG 0x04 32 #define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch)) 33 #define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch)) 34 #define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch)) 35 #define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch)) 36 #define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4) 37 #define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4) 38 #define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4) 39 #define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4) 40 #define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch)) 41 #define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch)) 42 #define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch)) 43 #define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch)) 44 #define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch)) 45 #define MAX6639_REG_DEVID 0x3D 46 #define MAX6639_REG_MANUID 0x3E 47 #define MAX6639_REG_DEVREV 0x3F 48 49 /* Register bits */ 50 #define MAX6639_GCONFIG_STANDBY 0x80 51 #define MAX6639_GCONFIG_POR 0x40 52 #define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20 53 #define MAX6639_GCONFIG_CH2_LOCAL 0x10 54 #define MAX6639_GCONFIG_PWM_FREQ_HI 0x08 55 56 #define MAX6639_FAN_CONFIG1_PWM 0x80 57 58 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40 59 60 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 }; 61 62 #define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \ 63 0 : (rpm_ranges[rpm_range] * 30) / (val)) 64 #define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255) 65 66 /* 67 * Client data (each client gets its own) 68 */ 69 struct max6639_data { 70 struct i2c_client *client; 71 struct mutex update_lock; 72 char valid; /* !=0 if following fields are valid */ 73 unsigned long last_updated; /* In jiffies */ 74 75 /* Register values sampled regularly */ 76 u16 temp[2]; /* Temperature, in 1/8 C, 0..255 C */ 77 bool temp_fault[2]; /* Detected temperature diode failure */ 78 u8 fan[2]; /* Register value: TACH count for fans >=30 */ 79 u8 status; /* Detected channel alarms and fan failures */ 80 81 /* Register values only written to */ 82 u8 pwm[2]; /* Register value: Duty cycle 0..120 */ 83 u8 temp_therm[2]; /* THERM Temperature, 0..255 C (->_max) */ 84 u8 temp_alert[2]; /* ALERT Temperature, 0..255 C (->_crit) */ 85 u8 temp_ot[2]; /* OT Temperature, 0..255 C (->_emergency) */ 86 87 /* Register values initialized only once */ 88 u8 ppr; /* Pulses per rotation 0..3 for 1..4 ppr */ 89 u8 rpm_range; /* Index in above rpm_ranges table */ 90 }; 91 92 static struct max6639_data *max6639_update_device(struct device *dev) 93 { 94 struct max6639_data *data = dev_get_drvdata(dev); 95 struct i2c_client *client = data->client; 96 struct max6639_data *ret = data; 97 int i; 98 int status_reg; 99 100 mutex_lock(&data->update_lock); 101 102 if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) { 103 int res; 104 105 dev_dbg(&client->dev, "Starting max6639 update\n"); 106 107 status_reg = i2c_smbus_read_byte_data(client, 108 MAX6639_REG_STATUS); 109 if (status_reg < 0) { 110 ret = ERR_PTR(status_reg); 111 goto abort; 112 } 113 114 data->status = status_reg; 115 116 for (i = 0; i < 2; i++) { 117 res = i2c_smbus_read_byte_data(client, 118 MAX6639_REG_FAN_CNT(i)); 119 if (res < 0) { 120 ret = ERR_PTR(res); 121 goto abort; 122 } 123 data->fan[i] = res; 124 125 res = i2c_smbus_read_byte_data(client, 126 MAX6639_REG_TEMP_EXT(i)); 127 if (res < 0) { 128 ret = ERR_PTR(res); 129 goto abort; 130 } 131 data->temp[i] = res >> 5; 132 data->temp_fault[i] = res & 0x01; 133 134 res = i2c_smbus_read_byte_data(client, 135 MAX6639_REG_TEMP(i)); 136 if (res < 0) { 137 ret = ERR_PTR(res); 138 goto abort; 139 } 140 data->temp[i] |= res << 3; 141 } 142 143 data->last_updated = jiffies; 144 data->valid = 1; 145 } 146 abort: 147 mutex_unlock(&data->update_lock); 148 149 return ret; 150 } 151 152 static ssize_t temp_input_show(struct device *dev, 153 struct device_attribute *dev_attr, char *buf) 154 { 155 long temp; 156 struct max6639_data *data = max6639_update_device(dev); 157 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 158 159 if (IS_ERR(data)) 160 return PTR_ERR(data); 161 162 temp = data->temp[attr->index] * 125; 163 return sprintf(buf, "%ld\n", temp); 164 } 165 166 static ssize_t temp_fault_show(struct device *dev, 167 struct device_attribute *dev_attr, char *buf) 168 { 169 struct max6639_data *data = max6639_update_device(dev); 170 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 171 172 if (IS_ERR(data)) 173 return PTR_ERR(data); 174 175 return sprintf(buf, "%d\n", data->temp_fault[attr->index]); 176 } 177 178 static ssize_t temp_max_show(struct device *dev, 179 struct device_attribute *dev_attr, char *buf) 180 { 181 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 182 struct max6639_data *data = dev_get_drvdata(dev); 183 184 return sprintf(buf, "%d\n", (data->temp_therm[attr->index] * 1000)); 185 } 186 187 static ssize_t temp_max_store(struct device *dev, 188 struct device_attribute *dev_attr, 189 const char *buf, size_t count) 190 { 191 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 192 struct max6639_data *data = dev_get_drvdata(dev); 193 struct i2c_client *client = data->client; 194 unsigned long val; 195 int res; 196 197 res = kstrtoul(buf, 10, &val); 198 if (res) 199 return res; 200 201 mutex_lock(&data->update_lock); 202 data->temp_therm[attr->index] = TEMP_LIMIT_TO_REG(val); 203 i2c_smbus_write_byte_data(client, 204 MAX6639_REG_THERM_LIMIT(attr->index), 205 data->temp_therm[attr->index]); 206 mutex_unlock(&data->update_lock); 207 return count; 208 } 209 210 static ssize_t temp_crit_show(struct device *dev, 211 struct device_attribute *dev_attr, char *buf) 212 { 213 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 214 struct max6639_data *data = dev_get_drvdata(dev); 215 216 return sprintf(buf, "%d\n", (data->temp_alert[attr->index] * 1000)); 217 } 218 219 static ssize_t temp_crit_store(struct device *dev, 220 struct device_attribute *dev_attr, 221 const char *buf, size_t count) 222 { 223 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 224 struct max6639_data *data = dev_get_drvdata(dev); 225 struct i2c_client *client = data->client; 226 unsigned long val; 227 int res; 228 229 res = kstrtoul(buf, 10, &val); 230 if (res) 231 return res; 232 233 mutex_lock(&data->update_lock); 234 data->temp_alert[attr->index] = TEMP_LIMIT_TO_REG(val); 235 i2c_smbus_write_byte_data(client, 236 MAX6639_REG_ALERT_LIMIT(attr->index), 237 data->temp_alert[attr->index]); 238 mutex_unlock(&data->update_lock); 239 return count; 240 } 241 242 static ssize_t temp_emergency_show(struct device *dev, 243 struct device_attribute *dev_attr, 244 char *buf) 245 { 246 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 247 struct max6639_data *data = dev_get_drvdata(dev); 248 249 return sprintf(buf, "%d\n", (data->temp_ot[attr->index] * 1000)); 250 } 251 252 static ssize_t temp_emergency_store(struct device *dev, 253 struct device_attribute *dev_attr, 254 const char *buf, size_t count) 255 { 256 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 257 struct max6639_data *data = dev_get_drvdata(dev); 258 struct i2c_client *client = data->client; 259 unsigned long val; 260 int res; 261 262 res = kstrtoul(buf, 10, &val); 263 if (res) 264 return res; 265 266 mutex_lock(&data->update_lock); 267 data->temp_ot[attr->index] = TEMP_LIMIT_TO_REG(val); 268 i2c_smbus_write_byte_data(client, 269 MAX6639_REG_OT_LIMIT(attr->index), 270 data->temp_ot[attr->index]); 271 mutex_unlock(&data->update_lock); 272 return count; 273 } 274 275 static ssize_t pwm_show(struct device *dev, struct device_attribute *dev_attr, 276 char *buf) 277 { 278 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 279 struct max6639_data *data = dev_get_drvdata(dev); 280 281 return sprintf(buf, "%d\n", data->pwm[attr->index] * 255 / 120); 282 } 283 284 static ssize_t pwm_store(struct device *dev, 285 struct device_attribute *dev_attr, const char *buf, 286 size_t count) 287 { 288 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 289 struct max6639_data *data = dev_get_drvdata(dev); 290 struct i2c_client *client = data->client; 291 unsigned long val; 292 int res; 293 294 res = kstrtoul(buf, 10, &val); 295 if (res) 296 return res; 297 298 val = clamp_val(val, 0, 255); 299 300 mutex_lock(&data->update_lock); 301 data->pwm[attr->index] = (u8)(val * 120 / 255); 302 i2c_smbus_write_byte_data(client, 303 MAX6639_REG_TARGTDUTY(attr->index), 304 data->pwm[attr->index]); 305 mutex_unlock(&data->update_lock); 306 return count; 307 } 308 309 static ssize_t fan_input_show(struct device *dev, 310 struct device_attribute *dev_attr, char *buf) 311 { 312 struct max6639_data *data = max6639_update_device(dev); 313 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 314 315 if (IS_ERR(data)) 316 return PTR_ERR(data); 317 318 return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[attr->index], 319 data->rpm_range)); 320 } 321 322 static ssize_t alarm_show(struct device *dev, 323 struct device_attribute *dev_attr, char *buf) 324 { 325 struct max6639_data *data = max6639_update_device(dev); 326 struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr); 327 328 if (IS_ERR(data)) 329 return PTR_ERR(data); 330 331 return sprintf(buf, "%d\n", !!(data->status & (1 << attr->index))); 332 } 333 334 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0); 335 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1); 336 static SENSOR_DEVICE_ATTR_RO(temp1_fault, temp_fault, 0); 337 static SENSOR_DEVICE_ATTR_RO(temp2_fault, temp_fault, 1); 338 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_max, 0); 339 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_max, 1); 340 static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp_crit, 0); 341 static SENSOR_DEVICE_ATTR_RW(temp2_crit, temp_crit, 1); 342 static SENSOR_DEVICE_ATTR_RW(temp1_emergency, temp_emergency, 0); 343 static SENSOR_DEVICE_ATTR_RW(temp2_emergency, temp_emergency, 1); 344 static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0); 345 static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, 1); 346 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0); 347 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1); 348 static SENSOR_DEVICE_ATTR_RO(fan1_fault, alarm, 1); 349 static SENSOR_DEVICE_ATTR_RO(fan2_fault, alarm, 0); 350 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 3); 351 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 2); 352 static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 7); 353 static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 6); 354 static SENSOR_DEVICE_ATTR_RO(temp1_emergency_alarm, alarm, 5); 355 static SENSOR_DEVICE_ATTR_RO(temp2_emergency_alarm, alarm, 4); 356 357 358 static struct attribute *max6639_attrs[] = { 359 &sensor_dev_attr_temp1_input.dev_attr.attr, 360 &sensor_dev_attr_temp2_input.dev_attr.attr, 361 &sensor_dev_attr_temp1_fault.dev_attr.attr, 362 &sensor_dev_attr_temp2_fault.dev_attr.attr, 363 &sensor_dev_attr_temp1_max.dev_attr.attr, 364 &sensor_dev_attr_temp2_max.dev_attr.attr, 365 &sensor_dev_attr_temp1_crit.dev_attr.attr, 366 &sensor_dev_attr_temp2_crit.dev_attr.attr, 367 &sensor_dev_attr_temp1_emergency.dev_attr.attr, 368 &sensor_dev_attr_temp2_emergency.dev_attr.attr, 369 &sensor_dev_attr_pwm1.dev_attr.attr, 370 &sensor_dev_attr_pwm2.dev_attr.attr, 371 &sensor_dev_attr_fan1_input.dev_attr.attr, 372 &sensor_dev_attr_fan2_input.dev_attr.attr, 373 &sensor_dev_attr_fan1_fault.dev_attr.attr, 374 &sensor_dev_attr_fan2_fault.dev_attr.attr, 375 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr, 376 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr, 377 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr, 378 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr, 379 &sensor_dev_attr_temp1_emergency_alarm.dev_attr.attr, 380 &sensor_dev_attr_temp2_emergency_alarm.dev_attr.attr, 381 NULL 382 }; 383 ATTRIBUTE_GROUPS(max6639); 384 385 /* 386 * returns respective index in rpm_ranges table 387 * 1 by default on invalid range 388 */ 389 static int rpm_range_to_reg(int range) 390 { 391 int i; 392 393 for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) { 394 if (rpm_ranges[i] == range) 395 return i; 396 } 397 398 return 1; /* default: 4000 RPM */ 399 } 400 401 static int max6639_init_client(struct i2c_client *client, 402 struct max6639_data *data) 403 { 404 struct max6639_platform_data *max6639_info = 405 dev_get_platdata(&client->dev); 406 int i; 407 int rpm_range = 1; /* default: 4000 RPM */ 408 int err; 409 410 /* Reset chip to default values, see below for GCONFIG setup */ 411 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, 412 MAX6639_GCONFIG_POR); 413 if (err) 414 goto exit; 415 416 /* Fans pulse per revolution is 2 by default */ 417 if (max6639_info && max6639_info->ppr > 0 && 418 max6639_info->ppr < 5) 419 data->ppr = max6639_info->ppr; 420 else 421 data->ppr = 2; 422 data->ppr -= 1; 423 424 if (max6639_info) 425 rpm_range = rpm_range_to_reg(max6639_info->rpm_range); 426 data->rpm_range = rpm_range; 427 428 for (i = 0; i < 2; i++) { 429 430 /* Set Fan pulse per revolution */ 431 err = i2c_smbus_write_byte_data(client, 432 MAX6639_REG_FAN_PPR(i), 433 data->ppr << 6); 434 if (err) 435 goto exit; 436 437 /* Fans config PWM, RPM */ 438 err = i2c_smbus_write_byte_data(client, 439 MAX6639_REG_FAN_CONFIG1(i), 440 MAX6639_FAN_CONFIG1_PWM | rpm_range); 441 if (err) 442 goto exit; 443 444 /* Fans PWM polarity high by default */ 445 if (max6639_info && max6639_info->pwm_polarity == 0) 446 err = i2c_smbus_write_byte_data(client, 447 MAX6639_REG_FAN_CONFIG2a(i), 0x00); 448 else 449 err = i2c_smbus_write_byte_data(client, 450 MAX6639_REG_FAN_CONFIG2a(i), 0x02); 451 if (err) 452 goto exit; 453 454 /* 455 * /THERM full speed enable, 456 * PWM frequency 25kHz, see also GCONFIG below 457 */ 458 err = i2c_smbus_write_byte_data(client, 459 MAX6639_REG_FAN_CONFIG3(i), 460 MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03); 461 if (err) 462 goto exit; 463 464 /* Max. temp. 80C/90C/100C */ 465 data->temp_therm[i] = 80; 466 data->temp_alert[i] = 90; 467 data->temp_ot[i] = 100; 468 err = i2c_smbus_write_byte_data(client, 469 MAX6639_REG_THERM_LIMIT(i), 470 data->temp_therm[i]); 471 if (err) 472 goto exit; 473 err = i2c_smbus_write_byte_data(client, 474 MAX6639_REG_ALERT_LIMIT(i), 475 data->temp_alert[i]); 476 if (err) 477 goto exit; 478 err = i2c_smbus_write_byte_data(client, 479 MAX6639_REG_OT_LIMIT(i), data->temp_ot[i]); 480 if (err) 481 goto exit; 482 483 /* PWM 120/120 (i.e. 100%) */ 484 data->pwm[i] = 120; 485 err = i2c_smbus_write_byte_data(client, 486 MAX6639_REG_TARGTDUTY(i), data->pwm[i]); 487 if (err) 488 goto exit; 489 } 490 /* Start monitoring */ 491 err = i2c_smbus_write_byte_data(client, MAX6639_REG_GCONFIG, 492 MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL | 493 MAX6639_GCONFIG_PWM_FREQ_HI); 494 exit: 495 return err; 496 } 497 498 /* Return 0 if detection is successful, -ENODEV otherwise */ 499 static int max6639_detect(struct i2c_client *client, 500 struct i2c_board_info *info) 501 { 502 struct i2c_adapter *adapter = client->adapter; 503 int dev_id, manu_id; 504 505 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 506 return -ENODEV; 507 508 /* Actual detection via device and manufacturer ID */ 509 dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID); 510 manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID); 511 if (dev_id != 0x58 || manu_id != 0x4D) 512 return -ENODEV; 513 514 strlcpy(info->type, "max6639", I2C_NAME_SIZE); 515 516 return 0; 517 } 518 519 static int max6639_probe(struct i2c_client *client, 520 const struct i2c_device_id *id) 521 { 522 struct device *dev = &client->dev; 523 struct max6639_data *data; 524 struct device *hwmon_dev; 525 int err; 526 527 data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL); 528 if (!data) 529 return -ENOMEM; 530 531 data->client = client; 532 mutex_init(&data->update_lock); 533 534 /* Initialize the max6639 chip */ 535 err = max6639_init_client(client, data); 536 if (err < 0) 537 return err; 538 539 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, 540 data, 541 max6639_groups); 542 return PTR_ERR_OR_ZERO(hwmon_dev); 543 } 544 545 #ifdef CONFIG_PM_SLEEP 546 static int max6639_suspend(struct device *dev) 547 { 548 struct i2c_client *client = to_i2c_client(dev); 549 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG); 550 if (data < 0) 551 return data; 552 553 return i2c_smbus_write_byte_data(client, 554 MAX6639_REG_GCONFIG, data | MAX6639_GCONFIG_STANDBY); 555 } 556 557 static int max6639_resume(struct device *dev) 558 { 559 struct i2c_client *client = to_i2c_client(dev); 560 int data = i2c_smbus_read_byte_data(client, MAX6639_REG_GCONFIG); 561 if (data < 0) 562 return data; 563 564 return i2c_smbus_write_byte_data(client, 565 MAX6639_REG_GCONFIG, data & ~MAX6639_GCONFIG_STANDBY); 566 } 567 #endif /* CONFIG_PM_SLEEP */ 568 569 static const struct i2c_device_id max6639_id[] = { 570 {"max6639", 0}, 571 { } 572 }; 573 574 MODULE_DEVICE_TABLE(i2c, max6639_id); 575 576 static SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume); 577 578 static struct i2c_driver max6639_driver = { 579 .class = I2C_CLASS_HWMON, 580 .driver = { 581 .name = "max6639", 582 .pm = &max6639_pm_ops, 583 }, 584 .probe = max6639_probe, 585 .id_table = max6639_id, 586 .detect = max6639_detect, 587 .address_list = normal_i2c, 588 }; 589 590 module_i2c_driver(max6639_driver); 591 592 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>"); 593 MODULE_DESCRIPTION("max6639 driver"); 594 MODULE_LICENSE("GPL"); 595