drivers/macintosh/therm_adt746x.c

   1 /*
   2  * Device driver for the i2c thermostat found on the iBook G4, Albook G4
   3  *
   4  * Copyright (C) 2003, 2004 Colin Leroy, Rasmus Rohde, Benjamin Herrenschmidt
   5  *
   6  * Documentation from
   7  * http://www.analog.com/UploadedFiles/Data_Sheets/115254175ADT7467_pra.pdf
   8  * http://www.analog.com/UploadedFiles/Data_Sheets/3686221171167ADT7460_b.pdf
   9  *
  10  */
  11
  12 #include <linux/types.h>
  13 #include <linux/module.h>
  14 #include <linux/errno.h>
  15 #include <linux/kernel.h>
  16 #include <linux/delay.h>
  17 #include <linux/sched.h>
  18 #include <linux/i2c.h>
  19 #include <linux/slab.h>
  20 #include <linux/init.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/smp_lock.h>
  23 #include <linux/wait.h>
  24 #include <linux/suspend.h>
  25 #include <linux/kthread.h>
  26 #include <linux/moduleparam.h>
  27 #include <linux/freezer.h>
  28
  29 #include <asm/prom.h>
  30 #include <asm/machdep.h>
  31 #include <asm/io.h>
  32 #include <asm/system.h>
  33 #include <asm/sections.h>
  34 #include <asm/of_platform.h>
  35
  36 #undef DEBUG
  37
  38 #define CONFIG_REG   0x40
  39 #define MANUAL_MASK  0xe0
  40 #define AUTO_MASK    0x20
  41
  42 static u8 TEMP_REG[3]    = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
  43 static u8 LIMIT_REG[3]   = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
  44 static u8 MANUAL_MODE[2] = {0x5c, 0x5d};
  45 static u8 REM_CONTROL[2] = {0x00, 0x40};
  46 static u8 FAN_SPEED[2]   = {0x28, 0x2a};
  47 static u8 FAN_SPD_SET[2] = {0x30, 0x31};
  48
  49 static u8 default_limits_local[3] = {70, 50, 70};    /* local, sensor1, sensor2 */
  50 static u8 default_limits_chip[3] = {80, 65, 80};    /* local, sensor1, sensor2 */
  51 static const char *sensor_location[3];
  52
  53 static int limit_adjust;
  54 static int fan_speed = -1;
  55 static int verbose;
  56
  57 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
  58 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
  59                    "Powerbook G4 Alu");
  60 MODULE_LICENSE("GPL");
  61
  62 module_param(limit_adjust, int, 0644);
  63 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
  64                  "by N degrees.");
  65
  66 module_param(fan_speed, int, 0644);
  67 MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "
  68                  "(default 64)");
  69
  70 module_param(verbose, bool, 0);
  71 MODULE_PARM_DESC(verbose,"Verbose log operations "
  72                  "(default 0)");
  73
  74 struct thermostat {
  75         struct i2c_client       clt;
  76         u8                      temps[3];
  77         u8                      cached_temp[3];
  78         u8                      initial_limits[3];
  79         u8                      limits[3];
  80         int                     last_speed[2];
  81         int                     last_var[2];
  82 };
  83
  84 static enum {ADT7460, ADT7467} therm_type;
  85 static int therm_bus, therm_address;
  86 static struct of_device * of_dev;
  87 static struct thermostat* thermostat;
  88 static struct task_struct *thread_therm = NULL;
  89
  90 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
  91                                  int busno);
  92
  93 static void write_both_fan_speed(struct thermostat *th, int speed);
  94 static void write_fan_speed(struct thermostat *th, int speed, int fan);
  95
  96 static int
  97 write_reg(struct thermostat* th, int reg, u8 data)
  98 {
  99         u8 tmp[2];
 100         int rc;
 101
 102         tmp[0] = reg;
 103         tmp[1] = data;
 104         rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
 105         if (rc < 0)
 106                 return rc;
 107         if (rc != 2)
 108                 return -ENODEV;
 109         return 0;
 110 }
 111
 112 static int
 113 read_reg(struct thermostat* th, int reg)
 114 {
 115         u8 reg_addr, data;
 116         int rc;
 117
 118         reg_addr = (u8)reg;
 119         rc = i2c_master_send(&th->clt, &reg_addr, 1);
 120         if (rc < 0)
 121                 return rc;
 122         if (rc != 1)
 123                 return -ENODEV;
 124         rc = i2c_master_recv(&th->clt, (char *)&data, 1);
 125         if (rc < 0)
 126                 return rc;
 127         return data;
 128 }
 129
 130 static int
 131 attach_thermostat(struct i2c_adapter *adapter)
 132 {
 133         unsigned long bus_no;
 134
 135         if (strncmp(adapter->name, "uni-n", 5))
 136                 return -ENODEV;
 137         bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
 138         if (bus_no != therm_bus)
 139                 return -ENODEV;
 140         return attach_one_thermostat(adapter, therm_address, bus_no);
 141 }
 142
 143 static int
 144 detach_thermostat(struct i2c_adapter *adapter)
 145 {
 146         struct thermostat* th;
 147         int i;
 148
 149         if (thermostat == NULL)
 150                 return 0;
 151
 152         th = thermostat;
 153
 154         if (thread_therm != NULL) {
 155                 kthread_stop(thread_therm);
 156         }
 157
 158         printk(KERN_INFO "adt746x: Putting max temperatures back from "
 159                          "%d, %d, %d to %d, %d, %d\n",
 160                 th->limits[0], th->limits[1], th->limits[2],
 161                 th->initial_limits[0], th->initial_limits[1],
 162                 th->initial_limits[2]);
 163
 164         for (i = 0; i < 3; i++)
 165                 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
 166
 167         write_both_fan_speed(th, -1);
 168
 169         i2c_detach_client(&th->clt);
 170
 171         thermostat = NULL;
 172
 173         kfree(th);
 174
 175         return 0;
 176 }
 177
 178 static struct i2c_driver thermostat_driver = {
 179         .driver = {
 180                 .name   = "therm_adt746x",
 181         },
 182         .attach_adapter = attach_thermostat,
 183         .detach_adapter = detach_thermostat,
 184 };
 185
 186 static int read_fan_speed(struct thermostat *th, u8 addr)
 187 {
 188         u8 tmp[2];
 189         u16 res;
 190
 191         /* should start with low byte */
 192         tmp[1] = read_reg(th, addr);
 193         tmp[0] = read_reg(th, addr + 1);
 194
 195         res = tmp[1] + (tmp[0] << 8);
 196         /* "a value of 0xffff means that the fan has stopped" */
 197         return (res == 0xffff ? 0 : (90000*60)/res);
 198 }
 199
 200 static void write_both_fan_speed(struct thermostat *th, int speed)
 201 {
 202         write_fan_speed(th, speed, 0);
 203         if (therm_type == ADT7460)
 204                 write_fan_speed(th, speed, 1);
 205 }
 206
 207 static void write_fan_speed(struct thermostat *th, int speed, int fan)
 208 {
 209         u8 manual;
 210
 211         if (speed > 0xff)
 212                 speed = 0xff;
 213         else if (speed < -1)
 214                 speed = 0;
 215
 216         if (therm_type == ADT7467 && fan == 1)
 217                 return;
 218
 219         if (th->last_speed[fan] != speed) {
 220                 if (verbose) {
 221                         if (speed == -1)
 222                                 printk(KERN_DEBUG "adt746x: Setting speed to automatic "
 223                                         "for %s fan.\n", sensor_location[fan+1]);
 224                         else
 225                                 printk(KERN_DEBUG "adt746x: Setting speed to %d "
 226                                         "for %s fan.\n", speed, sensor_location[fan+1]);
 227                 }
 228         } else
 229                 return;
 230
 231         if (speed >= 0) {
 232                 manual = read_reg(th, MANUAL_MODE[fan]);
 233                 write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK);
 234                 write_reg(th, FAN_SPD_SET[fan], speed);
 235         } else {
 236                 /* back to automatic */
 237                 if(therm_type == ADT7460) {
 238                         manual = read_reg(th,
 239                                 MANUAL_MODE[fan]) & (~MANUAL_MASK);
 240
 241                         write_reg(th,
 242                                 MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
 243                 } else {
 244                         manual = read_reg(th, MANUAL_MODE[fan]);
 245                         write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
 246                 }
 247         }
 248
 249         th->last_speed[fan] = speed;
 250 }
 251
 252 static void read_sensors(struct thermostat *th)
 253 {
 254         int i = 0;
 255
 256         for (i = 0; i < 3; i++)
 257                 th->temps[i]  = read_reg(th, TEMP_REG[i]);
 258 }
 259
 260 #ifdef DEBUG
 261 static void display_stats(struct thermostat *th)
 262 {
 263         if (th->temps[0] != th->cached_temp[0]
 264         ||  th->temps[1] != th->cached_temp[1]
 265         ||  th->temps[2] != th->cached_temp[2]) {
 266                 printk(KERN_INFO "adt746x: Temperature infos:"
 267                                  " thermostats: %d,%d,%d;"
 268                                  " limits: %d,%d,%d;"
 269                                  " fan speed: %d RPM\n",
 270                                  th->temps[0], th->temps[1], th->temps[2],
 271                                  th->limits[0],  th->limits[1],  th->limits[2],
 272                                  read_fan_speed(th, FAN_SPEED[0]));
 273         }
 274         th->cached_temp[0] = th->temps[0];
 275         th->cached_temp[1] = th->temps[1];
 276         th->cached_temp[2] = th->temps[2];
 277 }
 278 #endif
 279
 280 static void update_fans_speed (struct thermostat *th)
 281 {
 282         int lastvar = 0; /* last variation, for iBook */
 283         int i = 0;
 284
 285         /* we don't care about local sensor, so we start at sensor 1 */
 286         for (i = 1; i < 3; i++) {
 287                 int started = 0;
 288                 int fan_number = (therm_type == ADT7460 && i == 2);
 289                 int var = th->temps[i] - th->limits[i];
 290
 291                 if (var > -1) {
 292                         int step = (255 - fan_speed) / 7;
 293                         int new_speed = 0;
 294
 295                         /* hysteresis : change fan speed only if variation is
 296                          * more than two degrees */
 297                         if (abs(var - th->last_var[fan_number]) < 2)
 298                                 continue;
 299
 300                         started = 1;
 301                         new_speed = fan_speed + ((var-1)*step);
 302
 303                         if (new_speed < fan_speed)
 304                                 new_speed = fan_speed;
 305                         if (new_speed > 255)
 306                                 new_speed = 255;
 307
 308                         if (verbose)
 309                                 printk(KERN_DEBUG "adt746x: Setting fans speed to %d "
 310                                                  "(limit exceeded by %d on %s) \n",
 311                                                 new_speed, var,
 312                                                 sensor_location[fan_number+1]);
 313                         write_both_fan_speed(th, new_speed);
 314                         th->last_var[fan_number] = var;
 315                 } else if (var < -2) {
 316                         /* don't stop fan if sensor2 is cold and sensor1 is not
 317                          * so cold (lastvar >= -1) */
 318                         if (i == 2 && lastvar < -1) {
 319                                 if (th->last_speed[fan_number] != 0)
 320                                         if (verbose)
 321                                                 printk(KERN_DEBUG "adt746x: Stopping "
 322                                                         "fans.\n");
 323                                 write_both_fan_speed(th, 0);
 324                         }
 325                 }
 326
 327                 lastvar = var;
 328
 329                 if (started)
 330                         return; /* we don't want to re-stop the fan
 331                                 * if sensor1 is heating and sensor2 is not */
 332         }
 333 }
 334
 335 static int monitor_task(void *arg)
 336 {
 337         struct thermostat* th = arg;
 338
 339         while(!kthread_should_stop()) {
 340                 try_to_freeze();
 341                 msleep_interruptible(2000);
 342
 343 #ifndef DEBUG
 344                 if (fan_speed != -1)
 345                         read_sensors(th);
 346 #else
 347                 read_sensors(th);
 348 #endif
 349
 350                 if (fan_speed != -1)
 351                         update_fans_speed(th);
 352
 353 #ifdef DEBUG
 354                 display_stats(th);
 355 #endif
 356
 357         }
 358
 359         return 0;
 360 }
 361
 362 static void set_limit(struct thermostat *th, int i)
 363 {
 364                 /* Set sensor1 limit higher to avoid powerdowns */
 365                 th->limits[i] = default_limits_chip[i] + limit_adjust;
 366                 write_reg(th, LIMIT_REG[i], th->limits[i]);
 367
 368                 /* set our limits to normal */
 369                 th->limits[i] = default_limits_local[i] + limit_adjust;
 370 }
 371
 372 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
 373                                  int busno)
 374 {
 375         struct thermostat* th;
 376         int rc;
 377         int i;
 378
 379         if (thermostat)
 380                 return 0;
 381
 382         th = (struct thermostat *)
 383                 kmalloc(sizeof(struct thermostat), GFP_KERNEL);
 384
 385         if (!th)
 386                 return -ENOMEM;
 387
 388         memset(th, 0, sizeof(*th));
 389         th->clt.addr = addr;
 390         th->clt.adapter = adapter;
 391         th->clt.driver = &thermostat_driver;
 392         strcpy(th->clt.name, "thermostat");
 393
 394         rc = read_reg(th, 0);
 395         if (rc < 0) {
 396                 printk(KERN_ERR "adt746x: Thermostat failed to read config "
 397                                 "from bus %d !\n",
 398                                 busno);
 399                 kfree(th);
 400                 return -ENODEV;
 401         }
 402
 403         /* force manual control to start the fan quieter */
 404         if (fan_speed == -1)
 405                 fan_speed = 64;
 406
 407         if(therm_type == ADT7460) {
 408                 printk(KERN_INFO "adt746x: ADT7460 initializing\n");
 409                 /* The 7460 needs to be started explicitly */
 410                 write_reg(th, CONFIG_REG, 1);
 411         } else
 412                 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
 413
 414         for (i = 0; i < 3; i++) {
 415                 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
 416                 set_limit(th, i);
 417         }
 418
 419         printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
 420                          " to %d, %d, %d\n",
 421                          th->initial_limits[0], th->initial_limits[1],
 422                          th->initial_limits[2], th->limits[0], th->limits[1],
 423                          th->limits[2]);
 424
 425         thermostat = th;
 426
 427         if (i2c_attach_client(&th->clt)) {
 428                 printk(KERN_INFO "adt746x: Thermostat failed to attach "
 429                                  "client !\n");
 430                 thermostat = NULL;
 431                 kfree(th);
 432                 return -ENODEV;
 433         }
 434
 435         /* be sure to really write fan speed the first time */
 436         th->last_speed[0] = -2;
 437         th->last_speed[1] = -2;
 438         th->last_var[0] = -80;
 439         th->last_var[1] = -80;
 440
 441         if (fan_speed != -1) {
 442                 /* manual mode, stop fans */
 443                 write_both_fan_speed(th, 0);
 444         } else {
 445                 /* automatic mode */
 446                 write_both_fan_speed(th, -1);
 447         }
 448
 449         thread_therm = kthread_run(monitor_task, th, "kfand");
 450
 451         if (thread_therm == ERR_PTR(-ENOMEM)) {
 452                 printk(KERN_INFO "adt746x: Kthread creation failed\n");
 453                 thread_therm = NULL;
 454                 return -ENOMEM;
 455         }
 456
 457         return 0;
 458 }
 459
 460 /*
 461  * Now, unfortunately, sysfs doesn't give us a nice void * we could
 462  * pass around to the attribute functions, so we don't really have
 463  * choice but implement a bunch of them...
 464  *
 465  * FIXME, it does now...
 466  */
 467 #define BUILD_SHOW_FUNC_INT(name, data)                         \
 468 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
 469 {                                                               \
 470         return sprintf(buf, "%d\n", data);                      \
 471 }
 472
 473 #define BUILD_SHOW_FUNC_STR(name, data)                         \
 474 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)       \
 475 {                                                               \
 476         return sprintf(buf, "%s\n", data);                      \
 477 }
 478
 479 #define BUILD_SHOW_FUNC_FAN(name, data)                         \
 480 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)       \
 481 {                                                               \
 482         return sprintf(buf, "%d (%d rpm)\n",                    \
 483                 thermostat->last_speed[data],                   \
 484                 read_fan_speed(thermostat, FAN_SPEED[data])     \
 485                 );                                              \
 486 }
 487
 488 #define BUILD_STORE_FUNC_DEG(name, data)                        \
 489 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
 490 {                                                               \
 491         int val;                                                \
 492         int i;                                                  \
 493         val = simple_strtol(buf, NULL, 10);                     \
 494         printk(KERN_INFO "Adjusting limits by %d degrees\n", val);      \
 495         limit_adjust = val;                                     \
 496         for (i=0; i < 3; i++)                                   \
 497                 set_limit(thermostat, i);                       \
 498         return n;                                               \
 499 }
 500
 501 #define BUILD_STORE_FUNC_INT(name, data)                        \
 502 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
 503 {                                                               \
 504         u32 val;                                                \
 505         val = simple_strtoul(buf, NULL, 10);                    \
 506         if (val < 0 || val > 255)                               \
 507                 return -EINVAL;                                 \
 508         printk(KERN_INFO "Setting specified fan speed to %d\n", val);   \
 509         data = val;                                             \
 510         return n;                                               \
 511 }
 512
 513 BUILD_SHOW_FUNC_INT(sensor1_temperature,         (read_reg(thermostat, TEMP_REG[1])))
 514 BUILD_SHOW_FUNC_INT(sensor2_temperature,         (read_reg(thermostat, TEMP_REG[2])))
 515 BUILD_SHOW_FUNC_INT(sensor1_limit,               thermostat->limits[1])
 516 BUILD_SHOW_FUNC_INT(sensor2_limit,               thermostat->limits[2])
 517 BUILD_SHOW_FUNC_STR(sensor1_location,            sensor_location[1])
 518 BUILD_SHOW_FUNC_STR(sensor2_location,            sensor_location[2])
 519
 520 BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
 521 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed,   0)
 522 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed,   1)
 523
 524 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
 525 BUILD_SHOW_FUNC_INT(limit_adjust,        limit_adjust)
 526 BUILD_STORE_FUNC_DEG(limit_adjust,       thermostat)
 527
 528 static DEVICE_ATTR(sensor1_temperature, S_IRUGO,
 529                    show_sensor1_temperature,NULL);
 530 static DEVICE_ATTR(sensor2_temperature, S_IRUGO,
 531                    show_sensor2_temperature,NULL);
 532 static DEVICE_ATTR(sensor1_limit, S_IRUGO,
 533                    show_sensor1_limit,  NULL);
 534 static DEVICE_ATTR(sensor2_limit, S_IRUGO,
 535                    show_sensor2_limit,  NULL);
 536 static DEVICE_ATTR(sensor1_location, S_IRUGO,
 537                    show_sensor1_location, NULL);
 538 static DEVICE_ATTR(sensor2_location, S_IRUGO,
 539                    show_sensor2_location, NULL);
 540
 541 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
 542                    show_specified_fan_speed,store_specified_fan_speed);
 543
 544 static DEVICE_ATTR(sensor1_fan_speed,   S_IRUGO,
 545                    show_sensor1_fan_speed,      NULL);
 546 static DEVICE_ATTR(sensor2_fan_speed,   S_IRUGO,
 547                    show_sensor2_fan_speed,      NULL);
 548
 549 static DEVICE_ATTR(limit_adjust,        S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
 550                    show_limit_adjust,   store_limit_adjust);
 551
 552
 553 static int __init
 554 thermostat_init(void)
 555 {
 556         struct device_node* np;
 557         const u32 *prop;
 558         int i = 0, offset = 0;
 559
 560         np = of_find_node_by_name(NULL, "fan");
 561         if (!np)
 562                 return -ENODEV;
 563         if (device_is_compatible(np, "adt7460"))
 564                 therm_type = ADT7460;
 565         else if (device_is_compatible(np, "adt7467"))
 566                 therm_type = ADT7467;
 567         else
 568                 return -ENODEV;
 569
 570         prop = get_property(np, "hwsensor-params-version", NULL);
 571         printk(KERN_INFO "adt746x: version %d (%ssupported)\n", *prop,
 572                          (*prop == 1)?"":"un");
 573         if (*prop != 1)
 574                 return -ENODEV;
 575
 576         prop = get_property(np, "reg", NULL);
 577         if (!prop)
 578                 return -ENODEV;
 579
 580         /* look for bus either by path or using "reg" */
 581         if (strstr(np->full_name, "/i2c-bus@") != NULL) {
 582                 const char *tmp_bus = (strstr(np->full_name, "/i2c-bus@") + 9);
 583                 therm_bus = tmp_bus[0]-'0';
 584         } else {
 585                 therm_bus = ((*prop) >> 8) & 0x0f;
 586         }
 587
 588         therm_address = ((*prop) & 0xff) >> 1;
 589
 590         printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, "
 591                          "limit_adjust: %d, fan_speed: %d\n",
 592                          therm_bus, therm_address, limit_adjust, fan_speed);
 593
 594         if (get_property(np, "hwsensor-location", NULL)) {
 595                 for (i = 0; i < 3; i++) {
 596                         sensor_location[i] = get_property(np,
 597                                         "hwsensor-location", NULL) + offset;
 598
 599                         if (sensor_location[i] == NULL)
 600                                 sensor_location[i] = "";
 601
 602                         printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);
 603                         offset += strlen(sensor_location[i]) + 1;
 604                 }
 605         } else {
 606                 sensor_location[0] = "?";
 607                 sensor_location[1] = "?";
 608                 sensor_location[2] = "?";
 609         }
 610
 611         of_dev = of_platform_device_create(np, "temperatures", NULL);
 612
 613         if (of_dev == NULL) {
 614                 printk(KERN_ERR "Can't register temperatures device !\n");
 615                 return -ENODEV;
 616         }
 617
 618         device_create_file(&of_dev->dev, &dev_attr_sensor1_temperature);
 619         device_create_file(&of_dev->dev, &dev_attr_sensor2_temperature);
 620         device_create_file(&of_dev->dev, &dev_attr_sensor1_limit);
 621         device_create_file(&of_dev->dev, &dev_attr_sensor2_limit);
 622         device_create_file(&of_dev->dev, &dev_attr_sensor1_location);
 623         device_create_file(&of_dev->dev, &dev_attr_sensor2_location);
 624         device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
 625         device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
 626         device_create_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
 627         if(therm_type == ADT7460)
 628                 device_create_file(&of_dev->dev, &dev_attr_sensor2_fan_speed);
 629
 630 #ifndef CONFIG_I2C_POWERMAC
 631         request_module("i2c-powermac");
 632 #endif
 633
 634         return i2c_add_driver(&thermostat_driver);
 635 }
 636
 637 static void __exit
 638 thermostat_exit(void)
 639 {
 640         if (of_dev) {
 641                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_temperature);
 642                 device_remove_file(&of_dev->dev, &dev_attr_sensor2_temperature);
 643                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_limit);
 644                 device_remove_file(&of_dev->dev, &dev_attr_sensor2_limit);
 645                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_location);
 646                 device_remove_file(&of_dev->dev, &dev_attr_sensor2_location);
 647                 device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
 648                 device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
 649                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
 650
 651                 if(therm_type == ADT7460)
 652                         device_remove_file(&of_dev->dev,
 653                                            &dev_attr_sensor2_fan_speed);
 654
 655                 of_device_unregister(of_dev);
 656         }
 657         i2c_del_driver(&thermostat_driver);
 658 }
 659
 660 module_init(thermostat_init);
 661 module_exit(thermostat_exit);