1 /* 2 * max6650.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring. 4 * 5 * (C) 2007 by Hans J. Koch <hjk@hansjkoch.de> 6 * 7 * based on code written by John Morris <john.morris@spirentcom.com> 8 * Copyright (c) 2003 Spirent Communications 9 * and Claus Gindhart <claus.gindhart@kontron.com> 10 * 11 * This module has only been tested with the MAX6650 chip. It should 12 * also work with the MAX6651. It does not distinguish max6650 and max6651 13 * chips. 14 * 15 * The datasheet was last seen at: 16 * 17 * http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf 18 * 19 * This program is free software; you can redistribute it and/or modify 20 * it under the terms of the GNU General Public License as published by 21 * the Free Software Foundation; either version 2 of the License, or 22 * (at your option) any later version. 23 * 24 * This program is distributed in the hope that it will be useful, 25 * but WITHOUT ANY WARRANTY; without even the implied warranty of 26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 27 * GNU General Public License for more details. 28 * 29 * You should have received a copy of the GNU General Public License 30 * along with this program; if not, write to the Free Software 31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 32 */ 33 34 #include <linux/module.h> 35 #include <linux/init.h> 36 #include <linux/slab.h> 37 #include <linux/jiffies.h> 38 #include <linux/i2c.h> 39 #include <linux/hwmon.h> 40 #include <linux/hwmon-sysfs.h> 41 #include <linux/err.h> 42 #include <linux/of_device.h> 43 #include <linux/thermal.h> 44 45 /* 46 * Insmod parameters 47 */ 48 49 /* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */ 50 static int fan_voltage; 51 /* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */ 52 static int prescaler; 53 /* clock: The clock frequency of the chip (max6651 can be clocked externally) */ 54 static int clock = 254000; 55 56 module_param(fan_voltage, int, 0444); 57 module_param(prescaler, int, 0444); 58 module_param(clock, int, 0444); 59 60 /* 61 * MAX 6650/6651 registers 62 */ 63 64 #define MAX6650_REG_SPEED 0x00 65 #define MAX6650_REG_CONFIG 0x02 66 #define MAX6650_REG_GPIO_DEF 0x04 67 #define MAX6650_REG_DAC 0x06 68 #define MAX6650_REG_ALARM_EN 0x08 69 #define MAX6650_REG_ALARM 0x0A 70 #define MAX6650_REG_TACH0 0x0C 71 #define MAX6650_REG_TACH1 0x0E 72 #define MAX6650_REG_TACH2 0x10 73 #define MAX6650_REG_TACH3 0x12 74 #define MAX6650_REG_GPIO_STAT 0x14 75 #define MAX6650_REG_COUNT 0x16 76 77 /* 78 * Config register bits 79 */ 80 81 #define MAX6650_CFG_V12 0x08 82 #define MAX6650_CFG_PRESCALER_MASK 0x07 83 #define MAX6650_CFG_PRESCALER_2 0x01 84 #define MAX6650_CFG_PRESCALER_4 0x02 85 #define MAX6650_CFG_PRESCALER_8 0x03 86 #define MAX6650_CFG_PRESCALER_16 0x04 87 #define MAX6650_CFG_MODE_MASK 0x30 88 #define MAX6650_CFG_MODE_ON 0x00 89 #define MAX6650_CFG_MODE_OFF 0x10 90 #define MAX6650_CFG_MODE_CLOSED_LOOP 0x20 91 #define MAX6650_CFG_MODE_OPEN_LOOP 0x30 92 #define MAX6650_COUNT_MASK 0x03 93 94 /* 95 * Alarm status register bits 96 */ 97 98 #define MAX6650_ALRM_MAX 0x01 99 #define MAX6650_ALRM_MIN 0x02 100 #define MAX6650_ALRM_TACH 0x04 101 #define MAX6650_ALRM_GPIO1 0x08 102 #define MAX6650_ALRM_GPIO2 0x10 103 104 /* Minimum and maximum values of the FAN-RPM */ 105 #define FAN_RPM_MIN 240 106 #define FAN_RPM_MAX 30000 107 108 #define DIV_FROM_REG(reg) (1 << (reg & 7)) 109 110 /* 111 * Client data (each client gets its own) 112 */ 113 114 struct max6650_data { 115 struct i2c_client *client; 116 const struct attribute_group *groups[3]; 117 struct thermal_cooling_device *cooling_dev; 118 struct mutex update_lock; 119 int nr_fans; 120 char valid; /* zero until following fields are valid */ 121 unsigned long last_updated; /* in jiffies */ 122 123 /* register values */ 124 u8 speed; 125 u8 config; 126 u8 tach[4]; 127 u8 count; 128 u8 dac; 129 u8 alarm; 130 unsigned long cooling_dev_state; 131 }; 132 133 static const u8 tach_reg[] = { 134 MAX6650_REG_TACH0, 135 MAX6650_REG_TACH1, 136 MAX6650_REG_TACH2, 137 MAX6650_REG_TACH3, 138 }; 139 140 static const struct of_device_id __maybe_unused max6650_dt_match[] = { 141 { 142 .compatible = "maxim,max6650", 143 .data = (void *)1 144 }, 145 { 146 .compatible = "maxim,max6651", 147 .data = (void *)4 148 }, 149 { }, 150 }; 151 MODULE_DEVICE_TABLE(of, max6650_dt_match); 152 153 static struct max6650_data *max6650_update_device(struct device *dev) 154 { 155 struct max6650_data *data = dev_get_drvdata(dev); 156 struct i2c_client *client = data->client; 157 int i; 158 159 mutex_lock(&data->update_lock); 160 161 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { 162 data->speed = i2c_smbus_read_byte_data(client, 163 MAX6650_REG_SPEED); 164 data->config = i2c_smbus_read_byte_data(client, 165 MAX6650_REG_CONFIG); 166 for (i = 0; i < data->nr_fans; i++) { 167 data->tach[i] = i2c_smbus_read_byte_data(client, 168 tach_reg[i]); 169 } 170 data->count = i2c_smbus_read_byte_data(client, 171 MAX6650_REG_COUNT); 172 data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC); 173 174 /* 175 * Alarms are cleared on read in case the condition that 176 * caused the alarm is removed. Keep the value latched here 177 * for providing the register through different alarm files. 178 */ 179 data->alarm |= i2c_smbus_read_byte_data(client, 180 MAX6650_REG_ALARM); 181 182 data->last_updated = jiffies; 183 data->valid = 1; 184 } 185 186 mutex_unlock(&data->update_lock); 187 188 return data; 189 } 190 191 /* 192 * Change the operating mode of the chip (if needed). 193 * mode is one of the MAX6650_CFG_MODE_* values. 194 */ 195 static int max6650_set_operating_mode(struct max6650_data *data, u8 mode) 196 { 197 int result; 198 u8 config = data->config; 199 200 if (mode == (config & MAX6650_CFG_MODE_MASK)) 201 return 0; 202 203 config = (config & ~MAX6650_CFG_MODE_MASK) | mode; 204 205 result = i2c_smbus_write_byte_data(data->client, MAX6650_REG_CONFIG, 206 config); 207 if (result < 0) 208 return result; 209 210 data->config = config; 211 212 return 0; 213 } 214 215 static ssize_t fan_show(struct device *dev, struct device_attribute *devattr, 216 char *buf) 217 { 218 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 219 struct max6650_data *data = max6650_update_device(dev); 220 int rpm; 221 222 /* 223 * Calculation details: 224 * 225 * Each tachometer counts over an interval given by the "count" 226 * register (0.25, 0.5, 1 or 2 seconds). This module assumes 227 * that the fans produce two pulses per revolution (this seems 228 * to be the most common). 229 */ 230 231 rpm = ((data->tach[attr->index] * 120) / DIV_FROM_REG(data->count)); 232 return sprintf(buf, "%d\n", rpm); 233 } 234 235 /* 236 * Set the fan speed to the specified RPM (or read back the RPM setting). 237 * This works in closed loop mode only. Use pwm1 for open loop speed setting. 238 * 239 * The MAX6650/1 will automatically control fan speed when in closed loop 240 * mode. 241 * 242 * Assumptions: 243 * 244 * 1) The MAX6650/1 internal 254kHz clock frequency is set correctly. Use 245 * the clock module parameter if you need to fine tune this. 246 * 247 * 2) The prescaler (low three bits of the config register) has already 248 * been set to an appropriate value. Use the prescaler module parameter 249 * if your BIOS doesn't initialize the chip properly. 250 * 251 * The relevant equations are given on pages 21 and 22 of the datasheet. 252 * 253 * From the datasheet, the relevant equation when in regulation is: 254 * 255 * [fCLK / (128 x (KTACH + 1))] = 2 x FanSpeed / KSCALE 256 * 257 * where: 258 * 259 * fCLK is the oscillator frequency (either the 254kHz internal 260 * oscillator or the externally applied clock) 261 * 262 * KTACH is the value in the speed register 263 * 264 * FanSpeed is the speed of the fan in rps 265 * 266 * KSCALE is the prescaler value (1, 2, 4, 8, or 16) 267 * 268 * When reading, we need to solve for FanSpeed. When writing, we need to 269 * solve for KTACH. 270 * 271 * Note: this tachometer is completely separate from the tachometers 272 * used to measure the fan speeds. Only one fan's speed (fan1) is 273 * controlled. 274 */ 275 276 static ssize_t fan1_target_show(struct device *dev, 277 struct device_attribute *devattr, char *buf) 278 { 279 struct max6650_data *data = max6650_update_device(dev); 280 int kscale, ktach, rpm; 281 282 /* 283 * Use the datasheet equation: 284 * 285 * FanSpeed = KSCALE x fCLK / [256 x (KTACH + 1)] 286 * 287 * then multiply by 60 to give rpm. 288 */ 289 290 kscale = DIV_FROM_REG(data->config); 291 ktach = data->speed; 292 rpm = 60 * kscale * clock / (256 * (ktach + 1)); 293 return sprintf(buf, "%d\n", rpm); 294 } 295 296 static int max6650_set_target(struct max6650_data *data, unsigned long rpm) 297 { 298 int kscale, ktach; 299 300 if (rpm == 0) 301 return max6650_set_operating_mode(data, MAX6650_CFG_MODE_OFF); 302 303 rpm = clamp_val(rpm, FAN_RPM_MIN, FAN_RPM_MAX); 304 305 /* 306 * Divide the required speed by 60 to get from rpm to rps, then 307 * use the datasheet equation: 308 * 309 * KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1 310 */ 311 312 kscale = DIV_FROM_REG(data->config); 313 ktach = ((clock * kscale) / (256 * rpm / 60)) - 1; 314 if (ktach < 0) 315 ktach = 0; 316 if (ktach > 255) 317 ktach = 255; 318 data->speed = ktach; 319 320 return i2c_smbus_write_byte_data(data->client, MAX6650_REG_SPEED, 321 data->speed); 322 } 323 324 static ssize_t fan1_target_store(struct device *dev, 325 struct device_attribute *devattr, 326 const char *buf, size_t count) 327 { 328 struct max6650_data *data = dev_get_drvdata(dev); 329 unsigned long rpm; 330 int err; 331 332 err = kstrtoul(buf, 10, &rpm); 333 if (err) 334 return err; 335 336 mutex_lock(&data->update_lock); 337 338 err = max6650_set_target(data, rpm); 339 340 mutex_unlock(&data->update_lock); 341 342 if (err < 0) 343 return err; 344 345 return count; 346 } 347 348 /* 349 * Get/set the fan speed in open loop mode using pwm1 sysfs file. 350 * Speed is given as a relative value from 0 to 255, where 255 is maximum 351 * speed. Note that this is done by writing directly to the chip's DAC, 352 * it won't change the closed loop speed set by fan1_target. 353 * Also note that due to rounding errors it is possible that you don't read 354 * back exactly the value you have set. 355 */ 356 357 static ssize_t pwm1_show(struct device *dev, struct device_attribute *devattr, 358 char *buf) 359 { 360 int pwm; 361 struct max6650_data *data = max6650_update_device(dev); 362 363 /* 364 * Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans. 365 * Lower DAC values mean higher speeds. 366 */ 367 if (data->config & MAX6650_CFG_V12) 368 pwm = 255 - (255 * (int)data->dac)/180; 369 else 370 pwm = 255 - (255 * (int)data->dac)/76; 371 372 if (pwm < 0) 373 pwm = 0; 374 375 return sprintf(buf, "%d\n", pwm); 376 } 377 378 static ssize_t pwm1_store(struct device *dev, 379 struct device_attribute *devattr, const char *buf, 380 size_t count) 381 { 382 struct max6650_data *data = dev_get_drvdata(dev); 383 struct i2c_client *client = data->client; 384 unsigned long pwm; 385 int err; 386 387 err = kstrtoul(buf, 10, &pwm); 388 if (err) 389 return err; 390 391 pwm = clamp_val(pwm, 0, 255); 392 393 mutex_lock(&data->update_lock); 394 395 if (data->config & MAX6650_CFG_V12) 396 data->dac = 180 - (180 * pwm)/255; 397 else 398 data->dac = 76 - (76 * pwm)/255; 399 err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac); 400 401 mutex_unlock(&data->update_lock); 402 403 return err < 0 ? err : count; 404 } 405 406 /* 407 * Get/Set controller mode: 408 * Possible values: 409 * 0 = Fan always on 410 * 1 = Open loop, Voltage is set according to speed, not regulated. 411 * 2 = Closed loop, RPM for all fans regulated by fan1 tachometer 412 * 3 = Fan off 413 */ 414 static ssize_t pwm1_enable_show(struct device *dev, 415 struct device_attribute *devattr, char *buf) 416 { 417 struct max6650_data *data = max6650_update_device(dev); 418 int mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4; 419 int sysfs_modes[4] = {0, 3, 2, 1}; 420 421 return sprintf(buf, "%d\n", sysfs_modes[mode]); 422 } 423 424 static ssize_t pwm1_enable_store(struct device *dev, 425 struct device_attribute *devattr, 426 const char *buf, size_t count) 427 { 428 struct max6650_data *data = dev_get_drvdata(dev); 429 unsigned long mode; 430 int err; 431 const u8 max6650_modes[] = { 432 MAX6650_CFG_MODE_ON, 433 MAX6650_CFG_MODE_OPEN_LOOP, 434 MAX6650_CFG_MODE_CLOSED_LOOP, 435 MAX6650_CFG_MODE_OFF, 436 }; 437 438 err = kstrtoul(buf, 10, &mode); 439 if (err) 440 return err; 441 442 if (mode >= ARRAY_SIZE(max6650_modes)) 443 return -EINVAL; 444 445 mutex_lock(&data->update_lock); 446 447 max6650_set_operating_mode(data, max6650_modes[mode]); 448 449 mutex_unlock(&data->update_lock); 450 451 return count; 452 } 453 454 /* 455 * Read/write functions for fan1_div sysfs file. The MAX6650 has no such 456 * divider. We handle this by converting between divider and counttime: 457 * 458 * (counttime == k) <==> (divider == 2^k), k = 0, 1, 2, or 3 459 * 460 * Lower values of k allow to connect a faster fan without the risk of 461 * counter overflow. The price is lower resolution. You can also set counttime 462 * using the module parameter. Note that the module parameter "prescaler" also 463 * influences the behaviour. Unfortunately, there's no sysfs attribute 464 * defined for that. See the data sheet for details. 465 */ 466 467 static ssize_t fan1_div_show(struct device *dev, 468 struct device_attribute *devattr, char *buf) 469 { 470 struct max6650_data *data = max6650_update_device(dev); 471 472 return sprintf(buf, "%d\n", DIV_FROM_REG(data->count)); 473 } 474 475 static ssize_t fan1_div_store(struct device *dev, 476 struct device_attribute *devattr, 477 const char *buf, size_t count) 478 { 479 struct max6650_data *data = dev_get_drvdata(dev); 480 struct i2c_client *client = data->client; 481 unsigned long div; 482 int err; 483 484 err = kstrtoul(buf, 10, &div); 485 if (err) 486 return err; 487 488 mutex_lock(&data->update_lock); 489 switch (div) { 490 case 1: 491 data->count = 0; 492 break; 493 case 2: 494 data->count = 1; 495 break; 496 case 4: 497 data->count = 2; 498 break; 499 case 8: 500 data->count = 3; 501 break; 502 default: 503 mutex_unlock(&data->update_lock); 504 return -EINVAL; 505 } 506 507 i2c_smbus_write_byte_data(client, MAX6650_REG_COUNT, data->count); 508 mutex_unlock(&data->update_lock); 509 510 return count; 511 } 512 513 /* 514 * Get alarm stati: 515 * Possible values: 516 * 0 = no alarm 517 * 1 = alarm 518 */ 519 520 static ssize_t alarm_show(struct device *dev, 521 struct device_attribute *devattr, char *buf) 522 { 523 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 524 struct max6650_data *data = max6650_update_device(dev); 525 struct i2c_client *client = data->client; 526 int alarm = 0; 527 528 if (data->alarm & attr->index) { 529 mutex_lock(&data->update_lock); 530 alarm = 1; 531 data->alarm &= ~attr->index; 532 data->alarm |= i2c_smbus_read_byte_data(client, 533 MAX6650_REG_ALARM); 534 mutex_unlock(&data->update_lock); 535 } 536 537 return sprintf(buf, "%d\n", alarm); 538 } 539 540 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0); 541 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1); 542 static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 2); 543 static SENSOR_DEVICE_ATTR_RO(fan4_input, fan, 3); 544 static DEVICE_ATTR_RW(fan1_target); 545 static DEVICE_ATTR_RW(fan1_div); 546 static DEVICE_ATTR_RW(pwm1_enable); 547 static DEVICE_ATTR_RW(pwm1); 548 static SENSOR_DEVICE_ATTR_RO(fan1_max_alarm, alarm, MAX6650_ALRM_MAX); 549 static SENSOR_DEVICE_ATTR_RO(fan1_min_alarm, alarm, MAX6650_ALRM_MIN); 550 static SENSOR_DEVICE_ATTR_RO(fan1_fault, alarm, MAX6650_ALRM_TACH); 551 static SENSOR_DEVICE_ATTR_RO(gpio1_alarm, alarm, MAX6650_ALRM_GPIO1); 552 static SENSOR_DEVICE_ATTR_RO(gpio2_alarm, alarm, MAX6650_ALRM_GPIO2); 553 554 static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a, 555 int n) 556 { 557 struct device *dev = container_of(kobj, struct device, kobj); 558 struct max6650_data *data = dev_get_drvdata(dev); 559 struct i2c_client *client = data->client; 560 u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN); 561 struct device_attribute *devattr; 562 563 /* 564 * Hide the alarms that have not been enabled by the firmware 565 */ 566 567 devattr = container_of(a, struct device_attribute, attr); 568 if (devattr == &sensor_dev_attr_fan1_max_alarm.dev_attr 569 || devattr == &sensor_dev_attr_fan1_min_alarm.dev_attr 570 || devattr == &sensor_dev_attr_fan1_fault.dev_attr 571 || devattr == &sensor_dev_attr_gpio1_alarm.dev_attr 572 || devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) { 573 if (!(alarm_en & to_sensor_dev_attr(devattr)->index)) 574 return 0; 575 } 576 577 return a->mode; 578 } 579 580 static struct attribute *max6650_attrs[] = { 581 &sensor_dev_attr_fan1_input.dev_attr.attr, 582 &dev_attr_fan1_target.attr, 583 &dev_attr_fan1_div.attr, 584 &dev_attr_pwm1_enable.attr, 585 &dev_attr_pwm1.attr, 586 &sensor_dev_attr_fan1_max_alarm.dev_attr.attr, 587 &sensor_dev_attr_fan1_min_alarm.dev_attr.attr, 588 &sensor_dev_attr_fan1_fault.dev_attr.attr, 589 &sensor_dev_attr_gpio1_alarm.dev_attr.attr, 590 &sensor_dev_attr_gpio2_alarm.dev_attr.attr, 591 NULL 592 }; 593 594 static const struct attribute_group max6650_group = { 595 .attrs = max6650_attrs, 596 .is_visible = max6650_attrs_visible, 597 }; 598 599 static struct attribute *max6651_attrs[] = { 600 &sensor_dev_attr_fan2_input.dev_attr.attr, 601 &sensor_dev_attr_fan3_input.dev_attr.attr, 602 &sensor_dev_attr_fan4_input.dev_attr.attr, 603 NULL 604 }; 605 606 static const struct attribute_group max6651_group = { 607 .attrs = max6651_attrs, 608 }; 609 610 /* 611 * Real code 612 */ 613 614 static int max6650_init_client(struct max6650_data *data, 615 struct i2c_client *client) 616 { 617 struct device *dev = &client->dev; 618 int config; 619 int err = -EIO; 620 u32 voltage; 621 u32 prescale; 622 u32 target_rpm; 623 624 if (of_property_read_u32(dev->of_node, "maxim,fan-microvolt", 625 &voltage)) 626 voltage = fan_voltage; 627 else 628 voltage /= 1000000; /* Microvolts to volts */ 629 if (of_property_read_u32(dev->of_node, "maxim,fan-prescale", 630 &prescale)) 631 prescale = prescaler; 632 633 config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG); 634 635 if (config < 0) { 636 dev_err(dev, "Error reading config, aborting.\n"); 637 return err; 638 } 639 640 switch (voltage) { 641 case 0: 642 break; 643 case 5: 644 config &= ~MAX6650_CFG_V12; 645 break; 646 case 12: 647 config |= MAX6650_CFG_V12; 648 break; 649 default: 650 dev_err(dev, "illegal value for fan_voltage (%d)\n", voltage); 651 } 652 653 switch (prescale) { 654 case 0: 655 break; 656 case 1: 657 config &= ~MAX6650_CFG_PRESCALER_MASK; 658 break; 659 case 2: 660 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 661 | MAX6650_CFG_PRESCALER_2; 662 break; 663 case 4: 664 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 665 | MAX6650_CFG_PRESCALER_4; 666 break; 667 case 8: 668 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 669 | MAX6650_CFG_PRESCALER_8; 670 break; 671 case 16: 672 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 673 | MAX6650_CFG_PRESCALER_16; 674 break; 675 default: 676 dev_err(dev, "illegal value for prescaler (%d)\n", prescale); 677 } 678 679 dev_info(dev, "Fan voltage: %dV, prescaler: %d.\n", 680 (config & MAX6650_CFG_V12) ? 12 : 5, 681 1 << (config & MAX6650_CFG_PRESCALER_MASK)); 682 683 if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) { 684 dev_err(dev, "Config write error, aborting.\n"); 685 return err; 686 } 687 688 data->config = config; 689 data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT); 690 691 if (!of_property_read_u32(client->dev.of_node, "maxim,fan-target-rpm", 692 &target_rpm)) { 693 max6650_set_target(data, target_rpm); 694 max6650_set_operating_mode(data, MAX6650_CFG_MODE_CLOSED_LOOP); 695 } 696 697 return 0; 698 } 699 700 #if IS_ENABLED(CONFIG_THERMAL) 701 702 static int max6650_get_max_state(struct thermal_cooling_device *cdev, 703 unsigned long *state) 704 { 705 *state = 255; 706 707 return 0; 708 } 709 710 static int max6650_get_cur_state(struct thermal_cooling_device *cdev, 711 unsigned long *state) 712 { 713 struct max6650_data *data = cdev->devdata; 714 715 *state = data->cooling_dev_state; 716 717 return 0; 718 } 719 720 static int max6650_set_cur_state(struct thermal_cooling_device *cdev, 721 unsigned long state) 722 { 723 struct max6650_data *data = cdev->devdata; 724 struct i2c_client *client = data->client; 725 int err; 726 727 state = clamp_val(state, 0, 255); 728 729 mutex_lock(&data->update_lock); 730 731 if (data->config & MAX6650_CFG_V12) 732 data->dac = 180 - (180 * state)/255; 733 else 734 data->dac = 76 - (76 * state)/255; 735 736 err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac); 737 738 if (!err) { 739 max6650_set_operating_mode(data, state ? 740 MAX6650_CFG_MODE_OPEN_LOOP : 741 MAX6650_CFG_MODE_OFF); 742 data->cooling_dev_state = state; 743 } 744 745 mutex_unlock(&data->update_lock); 746 747 return err < 0 ? err : 0; 748 } 749 750 static const struct thermal_cooling_device_ops max6650_cooling_ops = { 751 .get_max_state = max6650_get_max_state, 752 .get_cur_state = max6650_get_cur_state, 753 .set_cur_state = max6650_set_cur_state, 754 }; 755 #endif 756 757 static int max6650_probe(struct i2c_client *client, 758 const struct i2c_device_id *id) 759 { 760 struct device *dev = &client->dev; 761 const struct of_device_id *of_id = 762 of_match_device(of_match_ptr(max6650_dt_match), dev); 763 struct max6650_data *data; 764 struct device *hwmon_dev; 765 int err; 766 767 data = devm_kzalloc(dev, sizeof(struct max6650_data), GFP_KERNEL); 768 if (!data) 769 return -ENOMEM; 770 771 data->client = client; 772 i2c_set_clientdata(client, data); 773 mutex_init(&data->update_lock); 774 data->nr_fans = of_id ? (int)(uintptr_t)of_id->data : id->driver_data; 775 776 /* 777 * Initialize the max6650 chip 778 */ 779 err = max6650_init_client(data, client); 780 if (err) 781 return err; 782 783 data->groups[0] = &max6650_group; 784 /* 3 additional fan inputs for the MAX6651 */ 785 if (data->nr_fans == 4) 786 data->groups[1] = &max6651_group; 787 788 hwmon_dev = devm_hwmon_device_register_with_groups(dev, 789 client->name, data, 790 data->groups); 791 err = PTR_ERR_OR_ZERO(hwmon_dev); 792 if (err) 793 return err; 794 795 #if IS_ENABLED(CONFIG_THERMAL) 796 data->cooling_dev = 797 thermal_of_cooling_device_register(client->dev.of_node, 798 client->name, data, 799 &max6650_cooling_ops); 800 if (IS_ERR(data->cooling_dev)) 801 dev_warn(&client->dev, 802 "thermal cooling device register failed: %ld\n", 803 PTR_ERR(data->cooling_dev)); 804 #endif 805 return 0; 806 } 807 808 static int max6650_remove(struct i2c_client *client) 809 { 810 struct max6650_data *data = i2c_get_clientdata(client); 811 812 if (!IS_ERR(data->cooling_dev)) 813 thermal_cooling_device_unregister(data->cooling_dev); 814 815 return 0; 816 } 817 818 static const struct i2c_device_id max6650_id[] = { 819 { "max6650", 1 }, 820 { "max6651", 4 }, 821 { } 822 }; 823 MODULE_DEVICE_TABLE(i2c, max6650_id); 824 825 static struct i2c_driver max6650_driver = { 826 .driver = { 827 .name = "max6650", 828 .of_match_table = of_match_ptr(max6650_dt_match), 829 }, 830 .probe = max6650_probe, 831 .remove = max6650_remove, 832 .id_table = max6650_id, 833 }; 834 835 module_i2c_driver(max6650_driver); 836 837 MODULE_AUTHOR("Hans J. Koch"); 838 MODULE_DESCRIPTION("MAX6650 sensor driver"); 839 MODULE_LICENSE("GPL"); 840