1 /* 2 * max6650.c - Part of lm_sensors, Linux kernel modules for hardware 3 * monitoring. 4 * 5 * (C) 2007 by Hans J. Koch <hjk@linutronix.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 * Tha 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 43 /* 44 * Addresses to scan. There are four disjoint possibilities, by pin config. 45 */ 46 47 static const unsigned short normal_i2c[] = {0x1b, 0x1f, 0x48, 0x4b, 48 I2C_CLIENT_END}; 49 50 /* 51 * Insmod parameters 52 */ 53 54 /* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */ 55 static int fan_voltage; 56 /* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */ 57 static int prescaler; 58 /* clock: The clock frequency of the chip the driver should assume */ 59 static int clock = 254000; 60 61 module_param(fan_voltage, int, S_IRUGO); 62 module_param(prescaler, int, S_IRUGO); 63 module_param(clock, int, S_IRUGO); 64 65 I2C_CLIENT_INSMOD_1(max6650); 66 67 /* 68 * MAX 6650/6651 registers 69 */ 70 71 #define MAX6650_REG_SPEED 0x00 72 #define MAX6650_REG_CONFIG 0x02 73 #define MAX6650_REG_GPIO_DEF 0x04 74 #define MAX6650_REG_DAC 0x06 75 #define MAX6650_REG_ALARM_EN 0x08 76 #define MAX6650_REG_ALARM 0x0A 77 #define MAX6650_REG_TACH0 0x0C 78 #define MAX6650_REG_TACH1 0x0E 79 #define MAX6650_REG_TACH2 0x10 80 #define MAX6650_REG_TACH3 0x12 81 #define MAX6650_REG_GPIO_STAT 0x14 82 #define MAX6650_REG_COUNT 0x16 83 84 /* 85 * Config register bits 86 */ 87 88 #define MAX6650_CFG_V12 0x08 89 #define MAX6650_CFG_PRESCALER_MASK 0x07 90 #define MAX6650_CFG_PRESCALER_2 0x01 91 #define MAX6650_CFG_PRESCALER_4 0x02 92 #define MAX6650_CFG_PRESCALER_8 0x03 93 #define MAX6650_CFG_PRESCALER_16 0x04 94 #define MAX6650_CFG_MODE_MASK 0x30 95 #define MAX6650_CFG_MODE_ON 0x00 96 #define MAX6650_CFG_MODE_OFF 0x10 97 #define MAX6650_CFG_MODE_CLOSED_LOOP 0x20 98 #define MAX6650_CFG_MODE_OPEN_LOOP 0x30 99 #define MAX6650_COUNT_MASK 0x03 100 101 /* Minimum and maximum values of the FAN-RPM */ 102 #define FAN_RPM_MIN 240 103 #define FAN_RPM_MAX 30000 104 105 #define DIV_FROM_REG(reg) (1 << (reg & 7)) 106 107 static int max6650_attach_adapter(struct i2c_adapter *adapter); 108 static int max6650_detect(struct i2c_adapter *adapter, int address, int kind); 109 static int max6650_init_client(struct i2c_client *client); 110 static int max6650_detach_client(struct i2c_client *client); 111 static struct max6650_data *max6650_update_device(struct device *dev); 112 113 /* 114 * Driver data (common to all clients) 115 */ 116 117 static struct i2c_driver max6650_driver = { 118 .driver = { 119 .name = "max6650", 120 }, 121 .attach_adapter = max6650_attach_adapter, 122 .detach_client = max6650_detach_client, 123 }; 124 125 /* 126 * Client data (each client gets its own) 127 */ 128 129 struct max6650_data 130 { 131 struct i2c_client client; 132 struct device *hwmon_dev; 133 struct mutex update_lock; 134 char valid; /* zero until following fields are valid */ 135 unsigned long last_updated; /* in jiffies */ 136 137 /* register values */ 138 u8 speed; 139 u8 config; 140 u8 tach[4]; 141 u8 count; 142 u8 dac; 143 }; 144 145 static ssize_t get_fan(struct device *dev, struct device_attribute *devattr, 146 char *buf) 147 { 148 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); 149 struct max6650_data *data = max6650_update_device(dev); 150 int rpm; 151 152 /* 153 * Calculation details: 154 * 155 * Each tachometer counts over an interval given by the "count" 156 * register (0.25, 0.5, 1 or 2 seconds). This module assumes 157 * that the fans produce two pulses per revolution (this seems 158 * to be the most common). 159 */ 160 161 rpm = ((data->tach[attr->index] * 120) / DIV_FROM_REG(data->count)); 162 return sprintf(buf, "%d\n", rpm); 163 } 164 165 /* 166 * Set the fan speed to the specified RPM (or read back the RPM setting). 167 * This works in closed loop mode only. Use pwm1 for open loop speed setting. 168 * 169 * The MAX6650/1 will automatically control fan speed when in closed loop 170 * mode. 171 * 172 * Assumptions: 173 * 174 * 1) The MAX6650/1 internal 254kHz clock frequency is set correctly. Use 175 * the clock module parameter if you need to fine tune this. 176 * 177 * 2) The prescaler (low three bits of the config register) has already 178 * been set to an appropriate value. Use the prescaler module parameter 179 * if your BIOS doesn't initialize the chip properly. 180 * 181 * The relevant equations are given on pages 21 and 22 of the datasheet. 182 * 183 * From the datasheet, the relevant equation when in regulation is: 184 * 185 * [fCLK / (128 x (KTACH + 1))] = 2 x FanSpeed / KSCALE 186 * 187 * where: 188 * 189 * fCLK is the oscillator frequency (either the 254kHz internal 190 * oscillator or the externally applied clock) 191 * 192 * KTACH is the value in the speed register 193 * 194 * FanSpeed is the speed of the fan in rps 195 * 196 * KSCALE is the prescaler value (1, 2, 4, 8, or 16) 197 * 198 * When reading, we need to solve for FanSpeed. When writing, we need to 199 * solve for KTACH. 200 * 201 * Note: this tachometer is completely separate from the tachometers 202 * used to measure the fan speeds. Only one fan's speed (fan1) is 203 * controlled. 204 */ 205 206 static ssize_t get_target(struct device *dev, struct device_attribute *devattr, 207 char *buf) 208 { 209 struct max6650_data *data = max6650_update_device(dev); 210 int kscale, ktach, rpm; 211 212 /* 213 * Use the datasheet equation: 214 * 215 * FanSpeed = KSCALE x fCLK / [256 x (KTACH + 1)] 216 * 217 * then multiply by 60 to give rpm. 218 */ 219 220 kscale = DIV_FROM_REG(data->config); 221 ktach = data->speed; 222 rpm = 60 * kscale * clock / (256 * (ktach + 1)); 223 return sprintf(buf, "%d\n", rpm); 224 } 225 226 static ssize_t set_target(struct device *dev, struct device_attribute *devattr, 227 const char *buf, size_t count) 228 { 229 struct i2c_client *client = to_i2c_client(dev); 230 struct max6650_data *data = i2c_get_clientdata(client); 231 int rpm = simple_strtoul(buf, NULL, 10); 232 int kscale, ktach; 233 234 rpm = SENSORS_LIMIT(rpm, FAN_RPM_MIN, FAN_RPM_MAX); 235 236 /* 237 * Divide the required speed by 60 to get from rpm to rps, then 238 * use the datasheet equation: 239 * 240 * KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1 241 */ 242 243 mutex_lock(&data->update_lock); 244 245 kscale = DIV_FROM_REG(data->config); 246 ktach = ((clock * kscale) / (256 * rpm / 60)) - 1; 247 if (ktach < 0) 248 ktach = 0; 249 if (ktach > 255) 250 ktach = 255; 251 data->speed = ktach; 252 253 i2c_smbus_write_byte_data(client, MAX6650_REG_SPEED, data->speed); 254 255 mutex_unlock(&data->update_lock); 256 257 return count; 258 } 259 260 /* 261 * Get/set the fan speed in open loop mode using pwm1 sysfs file. 262 * Speed is given as a relative value from 0 to 255, where 255 is maximum 263 * speed. Note that this is done by writing directly to the chip's DAC, 264 * it won't change the closed loop speed set by fan1_target. 265 * Also note that due to rounding errors it is possible that you don't read 266 * back exactly the value you have set. 267 */ 268 269 static ssize_t get_pwm(struct device *dev, struct device_attribute *devattr, 270 char *buf) 271 { 272 int pwm; 273 struct max6650_data *data = max6650_update_device(dev); 274 275 /* Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans. 276 Lower DAC values mean higher speeds. */ 277 if (data->config & MAX6650_CFG_V12) 278 pwm = 255 - (255 * (int)data->dac)/180; 279 else 280 pwm = 255 - (255 * (int)data->dac)/76; 281 282 if (pwm < 0) 283 pwm = 0; 284 285 return sprintf(buf, "%d\n", pwm); 286 } 287 288 static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr, 289 const char *buf, size_t count) 290 { 291 struct i2c_client *client = to_i2c_client(dev); 292 struct max6650_data *data = i2c_get_clientdata(client); 293 int pwm = simple_strtoul(buf, NULL, 10); 294 295 pwm = SENSORS_LIMIT(pwm, 0, 255); 296 297 mutex_lock(&data->update_lock); 298 299 if (data->config & MAX6650_CFG_V12) 300 data->dac = 180 - (180 * pwm)/255; 301 else 302 data->dac = 76 - (76 * pwm)/255; 303 304 i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac); 305 306 mutex_unlock(&data->update_lock); 307 308 return count; 309 } 310 311 /* 312 * Get/Set controller mode: 313 * Possible values: 314 * 0 = Fan always on 315 * 1 = Open loop, Voltage is set according to speed, not regulated. 316 * 2 = Closed loop, RPM for all fans regulated by fan1 tachometer 317 */ 318 319 static ssize_t get_enable(struct device *dev, struct device_attribute *devattr, 320 char *buf) 321 { 322 struct max6650_data *data = max6650_update_device(dev); 323 int mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4; 324 int sysfs_modes[4] = {0, 1, 2, 1}; 325 326 return sprintf(buf, "%d\n", sysfs_modes[mode]); 327 } 328 329 static ssize_t set_enable(struct device *dev, struct device_attribute *devattr, 330 const char *buf, size_t count) 331 { 332 struct i2c_client *client = to_i2c_client(dev); 333 struct max6650_data *data = i2c_get_clientdata(client); 334 int mode = simple_strtoul(buf, NULL, 10); 335 int max6650_modes[3] = {0, 3, 2}; 336 337 if ((mode < 0)||(mode > 2)) { 338 dev_err(&client->dev, 339 "illegal value for pwm1_enable (%d)\n", mode); 340 return -EINVAL; 341 } 342 343 mutex_lock(&data->update_lock); 344 345 data->config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG); 346 data->config = (data->config & ~MAX6650_CFG_MODE_MASK) 347 | (max6650_modes[mode] << 4); 348 349 i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, data->config); 350 351 mutex_unlock(&data->update_lock); 352 353 return count; 354 } 355 356 /* 357 * Read/write functions for fan1_div sysfs file. The MAX6650 has no such 358 * divider. We handle this by converting between divider and counttime: 359 * 360 * (counttime == k) <==> (divider == 2^k), k = 0, 1, 2, or 3 361 * 362 * Lower values of k allow to connect a faster fan without the risk of 363 * counter overflow. The price is lower resolution. You can also set counttime 364 * using the module parameter. Note that the module parameter "prescaler" also 365 * influences the behaviour. Unfortunately, there's no sysfs attribute 366 * defined for that. See the data sheet for details. 367 */ 368 369 static ssize_t get_div(struct device *dev, struct device_attribute *devattr, 370 char *buf) 371 { 372 struct max6650_data *data = max6650_update_device(dev); 373 374 return sprintf(buf, "%d\n", DIV_FROM_REG(data->count)); 375 } 376 377 static ssize_t set_div(struct device *dev, struct device_attribute *devattr, 378 const char *buf, size_t count) 379 { 380 struct i2c_client *client = to_i2c_client(dev); 381 struct max6650_data *data = i2c_get_clientdata(client); 382 int div = simple_strtoul(buf, NULL, 10); 383 384 mutex_lock(&data->update_lock); 385 switch (div) { 386 case 1: 387 data->count = 0; 388 break; 389 case 2: 390 data->count = 1; 391 break; 392 case 4: 393 data->count = 2; 394 break; 395 case 8: 396 data->count = 3; 397 break; 398 default: 399 dev_err(&client->dev, 400 "illegal value for fan divider (%d)\n", div); 401 return -EINVAL; 402 } 403 404 i2c_smbus_write_byte_data(client, MAX6650_REG_COUNT, data->count); 405 mutex_unlock(&data->update_lock); 406 407 return count; 408 } 409 410 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan, NULL, 0); 411 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, get_fan, NULL, 1); 412 static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, get_fan, NULL, 2); 413 static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, get_fan, NULL, 3); 414 static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO, get_target, set_target); 415 static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_div, set_div); 416 static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, get_enable, set_enable); 417 static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm); 418 419 420 static struct attribute *max6650_attrs[] = { 421 &sensor_dev_attr_fan1_input.dev_attr.attr, 422 &sensor_dev_attr_fan2_input.dev_attr.attr, 423 &sensor_dev_attr_fan3_input.dev_attr.attr, 424 &sensor_dev_attr_fan4_input.dev_attr.attr, 425 &dev_attr_fan1_target.attr, 426 &dev_attr_fan1_div.attr, 427 &dev_attr_pwm1_enable.attr, 428 &dev_attr_pwm1.attr, 429 NULL 430 }; 431 432 static struct attribute_group max6650_attr_grp = { 433 .attrs = max6650_attrs, 434 }; 435 436 /* 437 * Real code 438 */ 439 440 static int max6650_attach_adapter(struct i2c_adapter *adapter) 441 { 442 if (!(adapter->class & I2C_CLASS_HWMON)) { 443 dev_dbg(&adapter->dev, 444 "FATAL: max6650_attach_adapter class HWMON not set\n"); 445 return 0; 446 } 447 448 return i2c_probe(adapter, &addr_data, max6650_detect); 449 } 450 451 /* 452 * The following function does more than just detection. If detection 453 * succeeds, it also registers the new chip. 454 */ 455 456 static int max6650_detect(struct i2c_adapter *adapter, int address, int kind) 457 { 458 struct i2c_client *client; 459 struct max6650_data *data; 460 int err = -ENODEV; 461 462 dev_dbg(&adapter->dev, "max6650_detect called, kind = %d\n", kind); 463 464 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) { 465 dev_dbg(&adapter->dev, "max6650: I2C bus doesn't support " 466 "byte read mode, skipping.\n"); 467 return 0; 468 } 469 470 if (!(data = kzalloc(sizeof(struct max6650_data), GFP_KERNEL))) { 471 dev_err(&adapter->dev, "max6650: out of memory.\n"); 472 return -ENOMEM; 473 } 474 475 client = &data->client; 476 i2c_set_clientdata(client, data); 477 client->addr = address; 478 client->adapter = adapter; 479 client->driver = &max6650_driver; 480 481 /* 482 * Now we do the remaining detection. A negative kind means that 483 * the driver was loaded with no force parameter (default), so we 484 * must both detect and identify the chip (actually there is only 485 * one possible kind of chip for now, max6650). A zero kind means that 486 * the driver was loaded with the force parameter, the detection 487 * step shall be skipped. A positive kind means that the driver 488 * was loaded with the force parameter and a given kind of chip is 489 * requested, so both the detection and the identification steps 490 * are skipped. 491 * 492 * Currently I can find no way to distinguish between a MAX6650 and 493 * a MAX6651. This driver has only been tried on the former. 494 */ 495 496 if ((kind < 0) && 497 ( (i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG) & 0xC0) 498 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_GPIO_STAT) & 0xE0) 499 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN) & 0xE0) 500 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM) & 0xE0) 501 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT) & 0xFC))) { 502 dev_dbg(&adapter->dev, 503 "max6650: detection failed at 0x%02x.\n", address); 504 goto err_free; 505 } 506 507 dev_info(&adapter->dev, "max6650: chip found at 0x%02x.\n", address); 508 509 strlcpy(client->name, "max6650", I2C_NAME_SIZE); 510 mutex_init(&data->update_lock); 511 512 if ((err = i2c_attach_client(client))) { 513 dev_err(&adapter->dev, "max6650: failed to attach client.\n"); 514 goto err_free; 515 } 516 517 /* 518 * Initialize the max6650 chip 519 */ 520 if (max6650_init_client(client)) 521 goto err_detach; 522 523 err = sysfs_create_group(&client->dev.kobj, &max6650_attr_grp); 524 if (err) 525 goto err_detach; 526 527 data->hwmon_dev = hwmon_device_register(&client->dev); 528 if (!IS_ERR(data->hwmon_dev)) 529 return 0; 530 531 err = PTR_ERR(data->hwmon_dev); 532 dev_err(&client->dev, "error registering hwmon device.\n"); 533 sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp); 534 err_detach: 535 i2c_detach_client(client); 536 err_free: 537 kfree(data); 538 return err; 539 } 540 541 static int max6650_detach_client(struct i2c_client *client) 542 { 543 struct max6650_data *data = i2c_get_clientdata(client); 544 int err; 545 546 sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp); 547 hwmon_device_unregister(data->hwmon_dev); 548 err = i2c_detach_client(client); 549 if (!err) 550 kfree(data); 551 return err; 552 } 553 554 static int max6650_init_client(struct i2c_client *client) 555 { 556 struct max6650_data *data = i2c_get_clientdata(client); 557 int config; 558 int err = -EIO; 559 560 config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG); 561 562 if (config < 0) { 563 dev_err(&client->dev, "Error reading config, aborting.\n"); 564 return err; 565 } 566 567 switch (fan_voltage) { 568 case 0: 569 break; 570 case 5: 571 config &= ~MAX6650_CFG_V12; 572 break; 573 case 12: 574 config |= MAX6650_CFG_V12; 575 break; 576 default: 577 dev_err(&client->dev, 578 "illegal value for fan_voltage (%d)\n", 579 fan_voltage); 580 } 581 582 dev_info(&client->dev, "Fan voltage is set to %dV.\n", 583 (config & MAX6650_CFG_V12) ? 12 : 5); 584 585 switch (prescaler) { 586 case 0: 587 break; 588 case 1: 589 config &= ~MAX6650_CFG_PRESCALER_MASK; 590 break; 591 case 2: 592 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 593 | MAX6650_CFG_PRESCALER_2; 594 break; 595 case 4: 596 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 597 | MAX6650_CFG_PRESCALER_4; 598 break; 599 case 8: 600 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 601 | MAX6650_CFG_PRESCALER_8; 602 break; 603 case 16: 604 config = (config & ~MAX6650_CFG_PRESCALER_MASK) 605 | MAX6650_CFG_PRESCALER_16; 606 break; 607 default: 608 dev_err(&client->dev, 609 "illegal value for prescaler (%d)\n", 610 prescaler); 611 } 612 613 dev_info(&client->dev, "Prescaler is set to %d.\n", 614 1 << (config & MAX6650_CFG_PRESCALER_MASK)); 615 616 /* If mode is set to "full off", we change it to "open loop" and 617 * set DAC to 255, which has the same effect. We do this because 618 * there's no "full off" mode defined in hwmon specifcations. 619 */ 620 621 if ((config & MAX6650_CFG_MODE_MASK) == MAX6650_CFG_MODE_OFF) { 622 dev_dbg(&client->dev, "Change mode to open loop, full off.\n"); 623 config = (config & ~MAX6650_CFG_MODE_MASK) 624 | MAX6650_CFG_MODE_OPEN_LOOP; 625 if (i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, 255)) { 626 dev_err(&client->dev, "DAC write error, aborting.\n"); 627 return err; 628 } 629 } 630 631 if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) { 632 dev_err(&client->dev, "Config write error, aborting.\n"); 633 return err; 634 } 635 636 data->config = config; 637 data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT); 638 639 return 0; 640 } 641 642 static const u8 tach_reg[] = { 643 MAX6650_REG_TACH0, 644 MAX6650_REG_TACH1, 645 MAX6650_REG_TACH2, 646 MAX6650_REG_TACH3, 647 }; 648 649 static struct max6650_data *max6650_update_device(struct device *dev) 650 { 651 int i; 652 struct i2c_client *client = to_i2c_client(dev); 653 struct max6650_data *data = i2c_get_clientdata(client); 654 655 mutex_lock(&data->update_lock); 656 657 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { 658 data->speed = i2c_smbus_read_byte_data(client, 659 MAX6650_REG_SPEED); 660 data->config = i2c_smbus_read_byte_data(client, 661 MAX6650_REG_CONFIG); 662 for (i = 0; i < 4; i++) { 663 data->tach[i] = i2c_smbus_read_byte_data(client, 664 tach_reg[i]); 665 } 666 data->count = i2c_smbus_read_byte_data(client, 667 MAX6650_REG_COUNT); 668 data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC); 669 670 data->last_updated = jiffies; 671 data->valid = 1; 672 } 673 674 mutex_unlock(&data->update_lock); 675 676 return data; 677 } 678 679 static int __init sensors_max6650_init(void) 680 { 681 return i2c_add_driver(&max6650_driver); 682 } 683 684 static void __exit sensors_max6650_exit(void) 685 { 686 i2c_del_driver(&max6650_driver); 687 } 688 689 MODULE_AUTHOR("Hans J. Koch"); 690 MODULE_DESCRIPTION("MAX6650 sensor driver"); 691 MODULE_LICENSE("GPL"); 692 693 module_init(sensors_max6650_init); 694 module_exit(sensors_max6650_exit); 695