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/regmap.h> 23 #include <linux/util_macros.h> 24 25 /* Addresses to scan */ 26 static const unsigned short normal_i2c[] = { 0x2c, 0x2e, 0x2f, I2C_CLIENT_END }; 27 28 /* The MAX6639 registers, valid channel numbers: 0, 1 */ 29 #define MAX6639_REG_TEMP(ch) (0x00 + (ch)) 30 #define MAX6639_REG_STATUS 0x02 31 #define MAX6639_REG_OUTPUT_MASK 0x03 32 #define MAX6639_REG_GCONFIG 0x04 33 #define MAX6639_REG_TEMP_EXT(ch) (0x05 + (ch)) 34 #define MAX6639_REG_ALERT_LIMIT(ch) (0x08 + (ch)) 35 #define MAX6639_REG_OT_LIMIT(ch) (0x0A + (ch)) 36 #define MAX6639_REG_THERM_LIMIT(ch) (0x0C + (ch)) 37 #define MAX6639_REG_FAN_CONFIG1(ch) (0x10 + (ch) * 4) 38 #define MAX6639_REG_FAN_CONFIG2a(ch) (0x11 + (ch) * 4) 39 #define MAX6639_REG_FAN_CONFIG2b(ch) (0x12 + (ch) * 4) 40 #define MAX6639_REG_FAN_CONFIG3(ch) (0x13 + (ch) * 4) 41 #define MAX6639_REG_FAN_CNT(ch) (0x20 + (ch)) 42 #define MAX6639_REG_TARGET_CNT(ch) (0x22 + (ch)) 43 #define MAX6639_REG_FAN_PPR(ch) (0x24 + (ch)) 44 #define MAX6639_REG_TARGTDUTY(ch) (0x26 + (ch)) 45 #define MAX6639_REG_FAN_START_TEMP(ch) (0x28 + (ch)) 46 #define MAX6639_REG_DEVID 0x3D 47 #define MAX6639_REG_MANUID 0x3E 48 #define MAX6639_REG_DEVREV 0x3F 49 50 /* Register bits */ 51 #define MAX6639_GCONFIG_STANDBY 0x80 52 #define MAX6639_GCONFIG_POR 0x40 53 #define MAX6639_GCONFIG_DISABLE_TIMEOUT 0x20 54 #define MAX6639_GCONFIG_CH2_LOCAL 0x10 55 #define MAX6639_GCONFIG_PWM_FREQ_HI 0x08 56 57 #define MAX6639_FAN_CONFIG1_PWM 0x80 58 #define MAX6639_FAN_CONFIG3_FREQ_MASK 0x03 59 #define MAX6639_FAN_CONFIG3_THERM_FULL_SPEED 0x40 60 61 #define MAX6639_NUM_CHANNELS 2 62 63 static const int rpm_ranges[] = { 2000, 4000, 8000, 16000 }; 64 65 /* Supported PWM frequency */ 66 static const unsigned int freq_table[] = { 20, 33, 50, 100, 5000, 8333, 12500, 67 25000 }; 68 69 #define FAN_FROM_REG(val, rpm_range) ((val) == 0 || (val) == 255 ? \ 70 0 : (rpm_ranges[rpm_range] * 30) / (val)) 71 #define TEMP_LIMIT_TO_REG(val) clamp_val((val) / 1000, 0, 255) 72 73 /* 74 * Client data (each client gets its own) 75 */ 76 struct max6639_data { 77 struct regmap *regmap; 78 struct mutex update_lock; 79 80 /* Register values initialized only once */ 81 u8 ppr[MAX6639_NUM_CHANNELS]; /* Pulses per rotation 0..3 for 1..4 ppr */ 82 u8 rpm_range[MAX6639_NUM_CHANNELS]; /* Index in above rpm_ranges table */ 83 u32 target_rpm[MAX6639_NUM_CHANNELS]; 84 85 /* Optional regulator for FAN supply */ 86 struct regulator *reg; 87 }; 88 89 static int max6639_temp_read_input(struct device *dev, int channel, long *temp) 90 { 91 u32 regs[2] = { MAX6639_REG_TEMP_EXT(channel), MAX6639_REG_TEMP(channel) }; 92 struct max6639_data *data = dev_get_drvdata(dev); 93 u8 regvals[2]; 94 int res; 95 96 res = regmap_multi_reg_read(data->regmap, regs, regvals, 2); 97 if (res < 0) 98 return res; 99 100 *temp = ((regvals[0] >> 5) | (regvals[1] << 3)) * 125; 101 102 return 0; 103 } 104 105 static int max6639_temp_read_fault(struct device *dev, int channel, long *fault) 106 { 107 struct max6639_data *data = dev_get_drvdata(dev); 108 unsigned int val; 109 int res; 110 111 res = regmap_read(data->regmap, MAX6639_REG_TEMP_EXT(channel), &val); 112 if (res < 0) 113 return res; 114 115 *fault = val & 1; 116 117 return 0; 118 } 119 120 static int max6639_temp_read_max(struct device *dev, int channel, long *max) 121 { 122 struct max6639_data *data = dev_get_drvdata(dev); 123 unsigned int val; 124 int res; 125 126 res = regmap_read(data->regmap, MAX6639_REG_THERM_LIMIT(channel), &val); 127 if (res < 0) 128 return res; 129 130 *max = (long)val * 1000; 131 132 return 0; 133 } 134 135 static int max6639_temp_read_crit(struct device *dev, int channel, long *crit) 136 { 137 struct max6639_data *data = dev_get_drvdata(dev); 138 unsigned int val; 139 int res; 140 141 res = regmap_read(data->regmap, MAX6639_REG_ALERT_LIMIT(channel), &val); 142 if (res < 0) 143 return res; 144 145 *crit = (long)val * 1000; 146 147 return 0; 148 } 149 150 static int max6639_temp_read_emergency(struct device *dev, int channel, long *emerg) 151 { 152 struct max6639_data *data = dev_get_drvdata(dev); 153 unsigned int val; 154 int res; 155 156 res = regmap_read(data->regmap, MAX6639_REG_OT_LIMIT(channel), &val); 157 if (res < 0) 158 return res; 159 160 *emerg = (long)val * 1000; 161 162 return 0; 163 } 164 165 static int max6639_get_status(struct device *dev, unsigned int *status) 166 { 167 struct max6639_data *data = dev_get_drvdata(dev); 168 unsigned int val; 169 int res; 170 171 res = regmap_read(data->regmap, MAX6639_REG_STATUS, &val); 172 if (res < 0) 173 return res; 174 175 *status = val; 176 177 return 0; 178 } 179 180 static int max6639_temp_set_max(struct max6639_data *data, int channel, long val) 181 { 182 int res; 183 184 res = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(channel), 185 TEMP_LIMIT_TO_REG(val)); 186 return res; 187 } 188 189 static int max6639_temp_set_crit(struct max6639_data *data, int channel, long val) 190 { 191 int res; 192 193 res = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(channel), TEMP_LIMIT_TO_REG(val)); 194 195 return res; 196 } 197 198 static int max6639_temp_set_emergency(struct max6639_data *data, int channel, long val) 199 { 200 int res; 201 202 res = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(channel), TEMP_LIMIT_TO_REG(val)); 203 204 return res; 205 } 206 207 static int max6639_read_fan(struct device *dev, u32 attr, int channel, 208 long *fan_val) 209 { 210 struct max6639_data *data = dev_get_drvdata(dev); 211 unsigned int val; 212 int res; 213 214 switch (attr) { 215 case hwmon_fan_input: 216 res = regmap_read(data->regmap, MAX6639_REG_FAN_CNT(channel), &val); 217 if (res < 0) 218 return res; 219 *fan_val = FAN_FROM_REG(val, data->rpm_range[channel]); 220 return 0; 221 case hwmon_fan_fault: 222 res = max6639_get_status(dev, &val); 223 if (res < 0) 224 return res; 225 *fan_val = !!(val & BIT(1 - channel)); 226 return 0; 227 case hwmon_fan_pulses: 228 *fan_val = data->ppr[channel]; 229 return 0; 230 default: 231 return -EOPNOTSUPP; 232 } 233 } 234 235 static int max6639_set_ppr(struct max6639_data *data, int channel, u8 ppr) 236 { 237 /* Decrement the PPR value and shift left by 6 to match the register format */ 238 return regmap_write(data->regmap, MAX6639_REG_FAN_PPR(channel), ppr-- << 6); 239 } 240 241 static int max6639_write_fan(struct device *dev, u32 attr, int channel, 242 long val) 243 { 244 struct max6639_data *data = dev_get_drvdata(dev); 245 int err; 246 247 switch (attr) { 248 case hwmon_fan_pulses: 249 if (val <= 0 || val > 4) 250 return -EINVAL; 251 252 mutex_lock(&data->update_lock); 253 /* Set Fan pulse per revolution */ 254 err = max6639_set_ppr(data, channel, val); 255 if (err < 0) { 256 mutex_unlock(&data->update_lock); 257 return err; 258 } 259 data->ppr[channel] = val; 260 261 mutex_unlock(&data->update_lock); 262 return 0; 263 default: 264 return -EOPNOTSUPP; 265 } 266 } 267 268 static umode_t max6639_fan_is_visible(const void *_data, u32 attr, int channel) 269 { 270 switch (attr) { 271 case hwmon_fan_input: 272 case hwmon_fan_fault: 273 return 0444; 274 case hwmon_fan_pulses: 275 return 0644; 276 default: 277 return 0; 278 } 279 } 280 281 static int max6639_read_pwm(struct device *dev, u32 attr, int channel, 282 long *pwm_val) 283 { 284 u32 regs[2] = { MAX6639_REG_FAN_CONFIG3(channel), MAX6639_REG_GCONFIG }; 285 struct max6639_data *data = dev_get_drvdata(dev); 286 unsigned int val; 287 u8 regvals[2]; 288 int res; 289 u8 i; 290 291 switch (attr) { 292 case hwmon_pwm_input: 293 res = regmap_read(data->regmap, MAX6639_REG_TARGTDUTY(channel), &val); 294 if (res < 0) 295 return res; 296 *pwm_val = val * 255 / 120; 297 return 0; 298 case hwmon_pwm_freq: 299 res = regmap_multi_reg_read(data->regmap, regs, regvals, 2); 300 if (res < 0) 301 return res; 302 i = regvals[0] & MAX6639_FAN_CONFIG3_FREQ_MASK; 303 if (regvals[1] & MAX6639_GCONFIG_PWM_FREQ_HI) 304 i |= 0x4; 305 *pwm_val = freq_table[i]; 306 return 0; 307 default: 308 return -EOPNOTSUPP; 309 } 310 } 311 312 static int max6639_write_pwm(struct device *dev, u32 attr, int channel, 313 long val) 314 { 315 struct max6639_data *data = dev_get_drvdata(dev); 316 int err; 317 u8 i; 318 319 switch (attr) { 320 case hwmon_pwm_input: 321 if (val < 0 || val > 255) 322 return -EINVAL; 323 err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(channel), 324 val * 120 / 255); 325 return err; 326 case hwmon_pwm_freq: 327 val = clamp_val(val, 0, 25000); 328 329 i = find_closest(val, freq_table, ARRAY_SIZE(freq_table)); 330 331 mutex_lock(&data->update_lock); 332 err = regmap_update_bits(data->regmap, MAX6639_REG_FAN_CONFIG3(channel), 333 MAX6639_FAN_CONFIG3_FREQ_MASK, i); 334 if (err < 0) { 335 mutex_unlock(&data->update_lock); 336 return err; 337 } 338 339 if (i >> 2) 340 err = regmap_set_bits(data->regmap, MAX6639_REG_GCONFIG, 341 MAX6639_GCONFIG_PWM_FREQ_HI); 342 else 343 err = regmap_clear_bits(data->regmap, MAX6639_REG_GCONFIG, 344 MAX6639_GCONFIG_PWM_FREQ_HI); 345 346 mutex_unlock(&data->update_lock); 347 return err; 348 default: 349 return -EOPNOTSUPP; 350 } 351 } 352 353 static umode_t max6639_pwm_is_visible(const void *_data, u32 attr, int channel) 354 { 355 switch (attr) { 356 case hwmon_pwm_input: 357 case hwmon_pwm_freq: 358 return 0644; 359 default: 360 return 0; 361 } 362 } 363 364 static int max6639_read_temp(struct device *dev, u32 attr, int channel, 365 long *val) 366 { 367 unsigned int status; 368 int res; 369 370 switch (attr) { 371 case hwmon_temp_input: 372 res = max6639_temp_read_input(dev, channel, val); 373 return res; 374 case hwmon_temp_fault: 375 res = max6639_temp_read_fault(dev, channel, val); 376 return res; 377 case hwmon_temp_max: 378 res = max6639_temp_read_max(dev, channel, val); 379 return res; 380 case hwmon_temp_crit: 381 res = max6639_temp_read_crit(dev, channel, val); 382 return res; 383 case hwmon_temp_emergency: 384 res = max6639_temp_read_emergency(dev, channel, val); 385 return res; 386 case hwmon_temp_max_alarm: 387 res = max6639_get_status(dev, &status); 388 if (res < 0) 389 return res; 390 *val = !!(status & BIT(3 - channel)); 391 return 0; 392 case hwmon_temp_crit_alarm: 393 res = max6639_get_status(dev, &status); 394 if (res < 0) 395 return res; 396 *val = !!(status & BIT(7 - channel)); 397 return 0; 398 case hwmon_temp_emergency_alarm: 399 res = max6639_get_status(dev, &status); 400 if (res < 0) 401 return res; 402 *val = !!(status & BIT(5 - channel)); 403 return 0; 404 default: 405 return -EOPNOTSUPP; 406 } 407 } 408 409 static int max6639_write_temp(struct device *dev, u32 attr, int channel, 410 long val) 411 { 412 struct max6639_data *data = dev_get_drvdata(dev); 413 414 switch (attr) { 415 case hwmon_temp_max: 416 return max6639_temp_set_max(data, channel, val); 417 case hwmon_temp_crit: 418 return max6639_temp_set_crit(data, channel, val); 419 case hwmon_temp_emergency: 420 return max6639_temp_set_emergency(data, channel, val); 421 default: 422 return -EOPNOTSUPP; 423 } 424 } 425 426 static umode_t max6639_temp_is_visible(const void *_data, u32 attr, int channel) 427 { 428 switch (attr) { 429 case hwmon_temp_input: 430 case hwmon_temp_fault: 431 case hwmon_temp_max_alarm: 432 case hwmon_temp_crit_alarm: 433 case hwmon_temp_emergency_alarm: 434 return 0444; 435 case hwmon_temp_max: 436 case hwmon_temp_crit: 437 case hwmon_temp_emergency: 438 return 0644; 439 default: 440 return 0; 441 } 442 } 443 444 static int max6639_read(struct device *dev, enum hwmon_sensor_types type, 445 u32 attr, int channel, long *val) 446 { 447 switch (type) { 448 case hwmon_fan: 449 return max6639_read_fan(dev, attr, channel, val); 450 case hwmon_pwm: 451 return max6639_read_pwm(dev, attr, channel, val); 452 case hwmon_temp: 453 return max6639_read_temp(dev, attr, channel, val); 454 default: 455 return -EOPNOTSUPP; 456 } 457 } 458 459 static int max6639_write(struct device *dev, enum hwmon_sensor_types type, 460 u32 attr, int channel, long val) 461 { 462 switch (type) { 463 case hwmon_fan: 464 return max6639_write_fan(dev, attr, channel, val); 465 case hwmon_pwm: 466 return max6639_write_pwm(dev, attr, channel, val); 467 case hwmon_temp: 468 return max6639_write_temp(dev, attr, channel, val); 469 default: 470 return -EOPNOTSUPP; 471 } 472 } 473 474 static umode_t max6639_is_visible(const void *data, 475 enum hwmon_sensor_types type, 476 u32 attr, int channel) 477 { 478 switch (type) { 479 case hwmon_fan: 480 return max6639_fan_is_visible(data, attr, channel); 481 case hwmon_pwm: 482 return max6639_pwm_is_visible(data, attr, channel); 483 case hwmon_temp: 484 return max6639_temp_is_visible(data, attr, channel); 485 default: 486 return 0; 487 } 488 } 489 490 static const struct hwmon_channel_info * const max6639_info[] = { 491 HWMON_CHANNEL_INFO(fan, 492 HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES, 493 HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_PULSES), 494 HWMON_CHANNEL_INFO(pwm, 495 HWMON_PWM_INPUT | HWMON_PWM_FREQ, 496 HWMON_PWM_INPUT | HWMON_PWM_FREQ), 497 HWMON_CHANNEL_INFO(temp, 498 HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM | 499 HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY | 500 HWMON_T_EMERGENCY_ALARM, 501 HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_MAX | HWMON_T_MAX_ALARM | 502 HWMON_T_CRIT | HWMON_T_CRIT_ALARM | HWMON_T_EMERGENCY | 503 HWMON_T_EMERGENCY_ALARM), 504 NULL 505 }; 506 507 static const struct hwmon_ops max6639_hwmon_ops = { 508 .is_visible = max6639_is_visible, 509 .read = max6639_read, 510 .write = max6639_write, 511 }; 512 513 static const struct hwmon_chip_info max6639_chip_info = { 514 .ops = &max6639_hwmon_ops, 515 .info = max6639_info, 516 }; 517 518 /* 519 * returns respective index in rpm_ranges table 520 * 1 by default on invalid range 521 */ 522 static int rpm_range_to_reg(int range) 523 { 524 int i; 525 526 for (i = 0; i < ARRAY_SIZE(rpm_ranges); i++) { 527 if (rpm_ranges[i] == range) 528 return i; 529 } 530 531 return 1; /* default: 4000 RPM */ 532 } 533 534 static int max6639_probe_child_from_dt(struct i2c_client *client, 535 struct device_node *child, 536 struct max6639_data *data) 537 538 { 539 struct device *dev = &client->dev; 540 u32 i; 541 int err, val; 542 543 err = of_property_read_u32(child, "reg", &i); 544 if (err) { 545 dev_err(dev, "missing reg property of %pOFn\n", child); 546 return err; 547 } 548 549 if (i > 1) { 550 dev_err(dev, "Invalid fan index reg %d\n", i); 551 return -EINVAL; 552 } 553 554 err = of_property_read_u32(child, "pulses-per-revolution", &val); 555 if (!err) { 556 if (val < 1 || val > 5) { 557 dev_err(dev, "invalid pulses-per-revolution %d of %pOFn\n", val, child); 558 return -EINVAL; 559 } 560 data->ppr[i] = val; 561 } 562 563 err = of_property_read_u32(child, "max-rpm", &val); 564 if (!err) 565 data->rpm_range[i] = rpm_range_to_reg(val); 566 567 err = of_property_read_u32(child, "target-rpm", &val); 568 if (!err) 569 data->target_rpm[i] = val; 570 571 return 0; 572 } 573 574 static int max6639_init_client(struct i2c_client *client, 575 struct max6639_data *data) 576 { 577 struct device *dev = &client->dev; 578 const struct device_node *np = dev->of_node; 579 struct device_node *child; 580 int i, err; 581 u8 target_duty; 582 583 /* Reset chip to default values, see below for GCONFIG setup */ 584 err = regmap_write(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_POR); 585 if (err) 586 return err; 587 588 /* Fans pulse per revolution is 2 by default */ 589 data->ppr[0] = 2; 590 data->ppr[1] = 2; 591 592 /* default: 4000 RPM */ 593 data->rpm_range[0] = 1; 594 data->rpm_range[1] = 1; 595 data->target_rpm[0] = 4000; 596 data->target_rpm[1] = 4000; 597 598 for_each_child_of_node(np, child) { 599 if (strcmp(child->name, "fan")) 600 continue; 601 602 err = max6639_probe_child_from_dt(client, child, data); 603 if (err) { 604 of_node_put(child); 605 return err; 606 } 607 } 608 609 for (i = 0; i < MAX6639_NUM_CHANNELS; i++) { 610 err = regmap_set_bits(data->regmap, MAX6639_REG_OUTPUT_MASK, BIT(1 - i)); 611 if (err) 612 return err; 613 614 /* Set Fan pulse per revolution */ 615 err = max6639_set_ppr(data, i, data->ppr[i]); 616 if (err) 617 return err; 618 619 /* Fans config PWM, RPM */ 620 err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG1(i), 621 MAX6639_FAN_CONFIG1_PWM | data->rpm_range[i]); 622 if (err) 623 return err; 624 625 /* Fans PWM polarity high by default */ 626 err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG2a(i), 0x00); 627 if (err) 628 return err; 629 630 /* 631 * /THERM full speed enable, 632 * PWM frequency 25kHz, see also GCONFIG below 633 */ 634 err = regmap_write(data->regmap, MAX6639_REG_FAN_CONFIG3(i), 635 MAX6639_FAN_CONFIG3_THERM_FULL_SPEED | 0x03); 636 if (err) 637 return err; 638 639 /* Max. temp. 80C/90C/100C */ 640 err = regmap_write(data->regmap, MAX6639_REG_THERM_LIMIT(i), 80); 641 if (err) 642 return err; 643 err = regmap_write(data->regmap, MAX6639_REG_ALERT_LIMIT(i), 90); 644 if (err) 645 return err; 646 err = regmap_write(data->regmap, MAX6639_REG_OT_LIMIT(i), 100); 647 if (err) 648 return err; 649 650 /* Set PWM based on target RPM if specified */ 651 if (data->target_rpm[i] > rpm_ranges[data->rpm_range[i]]) 652 data->target_rpm[i] = rpm_ranges[data->rpm_range[i]]; 653 654 target_duty = 120 * data->target_rpm[i] / rpm_ranges[data->rpm_range[i]]; 655 err = regmap_write(data->regmap, MAX6639_REG_TARGTDUTY(i), target_duty); 656 if (err) 657 return err; 658 } 659 /* Start monitoring */ 660 return regmap_write(data->regmap, MAX6639_REG_GCONFIG, 661 MAX6639_GCONFIG_DISABLE_TIMEOUT | MAX6639_GCONFIG_CH2_LOCAL | 662 MAX6639_GCONFIG_PWM_FREQ_HI); 663 664 } 665 666 /* Return 0 if detection is successful, -ENODEV otherwise */ 667 static int max6639_detect(struct i2c_client *client, 668 struct i2c_board_info *info) 669 { 670 struct i2c_adapter *adapter = client->adapter; 671 int dev_id, manu_id; 672 673 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) 674 return -ENODEV; 675 676 /* Actual detection via device and manufacturer ID */ 677 dev_id = i2c_smbus_read_byte_data(client, MAX6639_REG_DEVID); 678 manu_id = i2c_smbus_read_byte_data(client, MAX6639_REG_MANUID); 679 if (dev_id != 0x58 || manu_id != 0x4D) 680 return -ENODEV; 681 682 strscpy(info->type, "max6639", I2C_NAME_SIZE); 683 684 return 0; 685 } 686 687 static void max6639_regulator_disable(void *data) 688 { 689 regulator_disable(data); 690 } 691 692 static bool max6639_regmap_is_volatile(struct device *dev, unsigned int reg) 693 { 694 switch (reg) { 695 case MAX6639_REG_TEMP(0): 696 case MAX6639_REG_TEMP_EXT(0): 697 case MAX6639_REG_TEMP(1): 698 case MAX6639_REG_TEMP_EXT(1): 699 case MAX6639_REG_STATUS: 700 case MAX6639_REG_FAN_CNT(0): 701 case MAX6639_REG_FAN_CNT(1): 702 case MAX6639_REG_TARGTDUTY(0): 703 case MAX6639_REG_TARGTDUTY(1): 704 return true; 705 default: 706 return false; 707 } 708 } 709 710 static const struct regmap_config max6639_regmap_config = { 711 .reg_bits = 8, 712 .val_bits = 8, 713 .max_register = MAX6639_REG_DEVREV, 714 .cache_type = REGCACHE_MAPLE, 715 .volatile_reg = max6639_regmap_is_volatile, 716 }; 717 718 static int max6639_probe(struct i2c_client *client) 719 { 720 struct device *dev = &client->dev; 721 struct max6639_data *data; 722 struct device *hwmon_dev; 723 int err; 724 725 data = devm_kzalloc(dev, sizeof(struct max6639_data), GFP_KERNEL); 726 if (!data) 727 return -ENOMEM; 728 729 data->regmap = devm_regmap_init_i2c(client, &max6639_regmap_config); 730 if (IS_ERR(data->regmap)) 731 return dev_err_probe(dev, 732 PTR_ERR(data->regmap), 733 "regmap initialization failed\n"); 734 735 data->reg = devm_regulator_get_optional(dev, "fan"); 736 if (IS_ERR(data->reg)) { 737 if (PTR_ERR(data->reg) != -ENODEV) 738 return PTR_ERR(data->reg); 739 740 data->reg = NULL; 741 } else { 742 /* Spin up fans */ 743 err = regulator_enable(data->reg); 744 if (err) { 745 dev_err(dev, "Failed to enable fan supply: %d\n", err); 746 return err; 747 } 748 err = devm_add_action_or_reset(dev, max6639_regulator_disable, 749 data->reg); 750 if (err) { 751 dev_err(dev, "Failed to register action: %d\n", err); 752 return err; 753 } 754 } 755 756 mutex_init(&data->update_lock); 757 758 /* Initialize the max6639 chip */ 759 err = max6639_init_client(client, data); 760 if (err < 0) 761 return err; 762 763 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, 764 data, &max6639_chip_info, 765 NULL); 766 767 return PTR_ERR_OR_ZERO(hwmon_dev); 768 } 769 770 static int max6639_suspend(struct device *dev) 771 { 772 struct max6639_data *data = dev_get_drvdata(dev); 773 774 if (data->reg) 775 regulator_disable(data->reg); 776 777 return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY, 778 MAX6639_GCONFIG_STANDBY); 779 } 780 781 static int max6639_resume(struct device *dev) 782 { 783 struct max6639_data *data = dev_get_drvdata(dev); 784 int ret; 785 786 if (data->reg) { 787 ret = regulator_enable(data->reg); 788 if (ret) { 789 dev_err(dev, "Failed to enable fan supply: %d\n", ret); 790 return ret; 791 } 792 } 793 794 return regmap_write_bits(data->regmap, MAX6639_REG_GCONFIG, MAX6639_GCONFIG_STANDBY, 795 ~MAX6639_GCONFIG_STANDBY); 796 } 797 798 static const struct i2c_device_id max6639_id[] = { 799 {"max6639"}, 800 { } 801 }; 802 803 MODULE_DEVICE_TABLE(i2c, max6639_id); 804 805 static DEFINE_SIMPLE_DEV_PM_OPS(max6639_pm_ops, max6639_suspend, max6639_resume); 806 807 static const struct of_device_id max6639_of_match[] = { 808 { .compatible = "maxim,max6639", }, 809 { }, 810 }; 811 812 static struct i2c_driver max6639_driver = { 813 .class = I2C_CLASS_HWMON, 814 .driver = { 815 .name = "max6639", 816 .pm = pm_sleep_ptr(&max6639_pm_ops), 817 .of_match_table = max6639_of_match, 818 }, 819 .probe = max6639_probe, 820 .id_table = max6639_id, 821 .detect = max6639_detect, 822 .address_list = normal_i2c, 823 }; 824 825 module_i2c_driver(max6639_driver); 826 827 MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>"); 828 MODULE_DESCRIPTION("max6639 driver"); 829 MODULE_LICENSE("GPL"); 830