d0d221332db0562e424cf8e98304e8fbd2013947
[linux-2.6.git] / 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/wait.h>
23 #include <linux/suspend.h>
24 #include <linux/kthread.h>
25 #include <linux/moduleparam.h>
26 #include <linux/freezer.h>
27 #include <linux/of_platform.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
35 #undef DEBUG
36
37 #define CONFIG_REG   0x40
38 #define MANUAL_MASK  0xe0
39 #define AUTO_MASK    0x20
40 #define INVERT_MASK  0x10
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         int                     pwm_inv[2];
83 };
84
85 static enum {ADT7460, ADT7467} therm_type;
86 static int therm_bus, therm_address;
87 static struct platform_device * of_dev;
88 static struct thermostat* thermostat;
89 static struct task_struct *thread_therm = NULL;
90
91 static void write_both_fan_speed(struct thermostat *th, int speed);
92 static void write_fan_speed(struct thermostat *th, int speed, int fan);
93 static void thermostat_create_files(void);
94 static void thermostat_remove_files(void);
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 struct i2c_driver thermostat_driver;
131
132 static int
133 attach_thermostat(struct i2c_adapter *adapter)
134 {
135         unsigned long bus_no;
136         struct i2c_board_info info;
137         struct i2c_client *client;
138
139         if (strncmp(adapter->name, "uni-n", 5))
140                 return -ENODEV;
141         bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
142         if (bus_no != therm_bus)
143                 return -ENODEV;
144
145         memset(&info, 0, sizeof(struct i2c_board_info));
146         strlcpy(info.type, "therm_adt746x", I2C_NAME_SIZE);
147         info.addr = therm_address;
148         client = i2c_new_device(adapter, &info);
149         if (!client)
150                 return -ENODEV;
151
152         /*
153          * Let i2c-core delete that device on driver removal.
154          * This is safe because i2c-core holds the core_lock mutex for us.
155          */
156         list_add_tail(&client->detected, &thermostat_driver.clients);
157         return 0;
158 }
159
160 static int
161 remove_thermostat(struct i2c_client *client)
162 {
163         struct thermostat *th = i2c_get_clientdata(client);
164         int i;
165         
166         thermostat_remove_files();
167
168         if (thread_therm != NULL) {
169                 kthread_stop(thread_therm);
170         }
171
172         printk(KERN_INFO "adt746x: Putting max temperatures back from "
173                          "%d, %d, %d to %d, %d, %d\n",
174                 th->limits[0], th->limits[1], th->limits[2],
175                 th->initial_limits[0], th->initial_limits[1],
176                 th->initial_limits[2]);
177
178         for (i = 0; i < 3; i++)
179                 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
180
181         write_both_fan_speed(th, -1);
182
183         thermostat = NULL;
184
185         kfree(th);
186
187         return 0;
188 }
189
190 static int read_fan_speed(struct thermostat *th, u8 addr)
191 {
192         u8 tmp[2];
193         u16 res;
194         
195         /* should start with low byte */
196         tmp[1] = read_reg(th, addr);
197         tmp[0] = read_reg(th, addr + 1);
198         
199         res = tmp[1] + (tmp[0] << 8);
200         /* "a value of 0xffff means that the fan has stopped" */
201         return (res == 0xffff ? 0 : (90000*60)/res);
202 }
203
204 static void write_both_fan_speed(struct thermostat *th, int speed)
205 {
206         write_fan_speed(th, speed, 0);
207         if (therm_type == ADT7460)
208                 write_fan_speed(th, speed, 1);
209 }
210
211 static void write_fan_speed(struct thermostat *th, int speed, int fan)
212 {
213         u8 manual;
214         
215         if (speed > 0xff) 
216                 speed = 0xff;
217         else if (speed < -1) 
218                 speed = 0;
219         
220         if (therm_type == ADT7467 && fan == 1)
221                 return;
222         
223         if (th->last_speed[fan] != speed) {
224                 if (verbose) {
225                         if (speed == -1)
226                                 printk(KERN_DEBUG "adt746x: Setting speed to automatic "
227                                         "for %s fan.\n", sensor_location[fan+1]);
228                         else
229                                 printk(KERN_DEBUG "adt746x: Setting speed to %d "
230                                         "for %s fan.\n", speed, sensor_location[fan+1]);
231                 }
232         } else
233                 return;
234         
235         if (speed >= 0) {
236                 manual = read_reg(th, MANUAL_MODE[fan]);
237                 manual &= ~INVERT_MASK;
238                 write_reg(th, MANUAL_MODE[fan],
239                         manual | MANUAL_MASK | th->pwm_inv[fan]);
240                 write_reg(th, FAN_SPD_SET[fan], speed);
241         } else {
242                 /* back to automatic */
243                 if(therm_type == ADT7460) {
244                         manual = read_reg(th,
245                                 MANUAL_MODE[fan]) & (~MANUAL_MASK);
246                         manual &= ~INVERT_MASK;
247                         manual |= th->pwm_inv[fan];
248                         write_reg(th,
249                                 MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
250                 } else {
251                         manual = read_reg(th, MANUAL_MODE[fan]);
252                         manual &= ~INVERT_MASK;
253                         manual |= th->pwm_inv[fan];
254                         write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
255                 }
256         }
257         
258         th->last_speed[fan] = speed;                    
259 }
260
261 static void read_sensors(struct thermostat *th)
262 {
263         int i = 0;
264
265         for (i = 0; i < 3; i++)
266                 th->temps[i]  = read_reg(th, TEMP_REG[i]);
267 }
268
269 #ifdef DEBUG
270 static void display_stats(struct thermostat *th)
271 {
272         if (th->temps[0] != th->cached_temp[0]
273         ||  th->temps[1] != th->cached_temp[1]
274         ||  th->temps[2] != th->cached_temp[2]) {
275                 printk(KERN_INFO "adt746x: Temperature infos:"
276                                  " thermostats: %d,%d,%d;"
277                                  " limits: %d,%d,%d;"
278                                  " fan speed: %d RPM\n",
279                                  th->temps[0], th->temps[1], th->temps[2],
280                                  th->limits[0],  th->limits[1],  th->limits[2],
281                                  read_fan_speed(th, FAN_SPEED[0]));
282         }
283         th->cached_temp[0] = th->temps[0];
284         th->cached_temp[1] = th->temps[1];
285         th->cached_temp[2] = th->temps[2];
286 }
287 #endif
288
289 static void update_fans_speed (struct thermostat *th)
290 {
291         int lastvar = 0; /* last variation, for iBook */
292         int i = 0;
293
294         /* we don't care about local sensor, so we start at sensor 1 */
295         for (i = 1; i < 3; i++) {
296                 int started = 0;
297                 int fan_number = (therm_type == ADT7460 && i == 2);
298                 int var = th->temps[i] - th->limits[i];
299
300                 if (var > -1) {
301                         int step = (255 - fan_speed) / 7;
302                         int new_speed = 0;
303
304                         /* hysteresis : change fan speed only if variation is
305                          * more than two degrees */
306                         if (abs(var - th->last_var[fan_number]) < 2)
307                                 continue;
308
309                         started = 1;
310                         new_speed = fan_speed + ((var-1)*step);
311
312                         if (new_speed < fan_speed)
313                                 new_speed = fan_speed;
314                         if (new_speed > 255)
315                                 new_speed = 255;
316
317                         if (verbose)
318                                 printk(KERN_DEBUG "adt746x: Setting fans speed to %d "
319                                                  "(limit exceeded by %d on %s)\n",
320                                                 new_speed, var,
321                                                 sensor_location[fan_number+1]);
322                         write_both_fan_speed(th, new_speed);
323                         th->last_var[fan_number] = var;
324                 } else if (var < -2) {
325                         /* don't stop fan if sensor2 is cold and sensor1 is not
326                          * so cold (lastvar >= -1) */
327                         if (i == 2 && lastvar < -1) {
328                                 if (th->last_speed[fan_number] != 0)
329                                         if (verbose)
330                                                 printk(KERN_DEBUG "adt746x: Stopping "
331                                                         "fans.\n");
332                                 write_both_fan_speed(th, 0);
333                         }
334                 }
335
336                 lastvar = var;
337
338                 if (started)
339                         return; /* we don't want to re-stop the fan
340                                 * if sensor1 is heating and sensor2 is not */
341         }
342 }
343
344 static int monitor_task(void *arg)
345 {
346         struct thermostat* th = arg;
347
348         set_freezable();
349         while(!kthread_should_stop()) {
350                 try_to_freeze();
351                 msleep_interruptible(2000);
352
353 #ifndef DEBUG
354                 if (fan_speed != -1)
355                         read_sensors(th);
356 #else
357                 read_sensors(th);
358 #endif          
359
360                 if (fan_speed != -1)
361                         update_fans_speed(th);
362
363 #ifdef DEBUG
364                 display_stats(th);
365 #endif
366
367         }
368
369         return 0;
370 }
371
372 static void set_limit(struct thermostat *th, int i)
373 {
374                 /* Set sensor1 limit higher to avoid powerdowns */
375                 th->limits[i] = default_limits_chip[i] + limit_adjust;
376                 write_reg(th, LIMIT_REG[i], th->limits[i]);
377                 
378                 /* set our limits to normal */
379                 th->limits[i] = default_limits_local[i] + limit_adjust;
380 }
381
382 static int probe_thermostat(struct i2c_client *client,
383                             const struct i2c_device_id *id)
384 {
385         struct thermostat* th;
386         int rc;
387         int i;
388
389         if (thermostat)
390                 return 0;
391
392         th = kzalloc(sizeof(struct thermostat), GFP_KERNEL);
393         if (!th)
394                 return -ENOMEM;
395
396         i2c_set_clientdata(client, th);
397         th->clt = client;
398
399         rc = read_reg(th, CONFIG_REG);
400         if (rc < 0) {
401                 dev_err(&client->dev, "Thermostat failed to read config!\n");
402                 kfree(th);
403                 return -ENODEV;
404         }
405
406         /* force manual control to start the fan quieter */
407         if (fan_speed == -1)
408                 fan_speed = 64;
409         
410         if(therm_type == ADT7460) {
411                 printk(KERN_INFO "adt746x: ADT7460 initializing\n");
412                 /* The 7460 needs to be started explicitly */
413                 write_reg(th, CONFIG_REG, 1);
414         } else
415                 printk(KERN_INFO "adt746x: ADT7467 initializing\n");
416
417         for (i = 0; i < 3; i++) {
418                 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
419                 set_limit(th, i);
420         }
421
422         printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
423                          " to %d, %d, %d\n",
424                          th->initial_limits[0], th->initial_limits[1],
425                          th->initial_limits[2], th->limits[0], th->limits[1],
426                          th->limits[2]);
427
428         thermostat = th;
429
430         /* record invert bit status because fw can corrupt it after suspend */
431         th->pwm_inv[0] = read_reg(th, MANUAL_MODE[0]) & INVERT_MASK;
432         th->pwm_inv[1] = read_reg(th, MANUAL_MODE[1]) & INVERT_MASK;
433
434         /* be sure to really write fan speed the first time */
435         th->last_speed[0] = -2;
436         th->last_speed[1] = -2;
437         th->last_var[0] = -80;
438         th->last_var[1] = -80;
439
440         if (fan_speed != -1) {
441                 /* manual mode, stop fans */
442                 write_both_fan_speed(th, 0);
443         } else {
444                 /* automatic mode */
445                 write_both_fan_speed(th, -1);
446         }
447         
448         thread_therm = kthread_run(monitor_task, th, "kfand");
449
450         if (thread_therm == ERR_PTR(-ENOMEM)) {
451                 printk(KERN_INFO "adt746x: Kthread creation failed\n");
452                 thread_therm = NULL;
453                 return -ENOMEM;
454         }
455
456         thermostat_create_files();
457
458         return 0;
459 }
460
461 static const struct i2c_device_id therm_adt746x_id[] = {
462         { "therm_adt746x", 0 },
463         { }
464 };
465
466 static struct i2c_driver thermostat_driver = {
467         .driver = {
468                 .name   = "therm_adt746x",
469         },
470         .attach_adapter = attach_thermostat,
471         .probe = probe_thermostat,
472         .remove = remove_thermostat,
473         .id_table = therm_adt746x_id,
474 };
475
476 /* 
477  * Now, unfortunately, sysfs doesn't give us a nice void * we could
478  * pass around to the attribute functions, so we don't really have
479  * choice but implement a bunch of them...
480  *
481  * FIXME, it does now...
482  */
483 #define BUILD_SHOW_FUNC_INT(name, data)                         \
484 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
485 {                                                               \
486         return sprintf(buf, "%d\n", data);                      \
487 }
488
489 #define BUILD_SHOW_FUNC_STR(name, data)                         \
490 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)       \
491 {                                                               \
492         return sprintf(buf, "%s\n", data);                      \
493 }
494
495 #define BUILD_SHOW_FUNC_FAN(name, data)                         \
496 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)       \
497 {                                                               \
498         return sprintf(buf, "%d (%d rpm)\n",                    \
499                 thermostat->last_speed[data],                   \
500                 read_fan_speed(thermostat, FAN_SPEED[data])     \
501                 );                                              \
502 }
503
504 #define BUILD_STORE_FUNC_DEG(name, data)                        \
505 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
506 {                                                               \
507         int val;                                                \
508         int i;                                                  \
509         val = simple_strtol(buf, NULL, 10);                     \
510         printk(KERN_INFO "Adjusting limits by %d degrees\n", val);      \
511         limit_adjust = val;                                     \
512         for (i=0; i < 3; i++)                                   \
513                 set_limit(thermostat, i);                       \
514         return n;                                               \
515 }
516
517 #define BUILD_STORE_FUNC_INT(name, data)                        \
518 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
519 {                                                               \
520         int val;                                                \
521         val = simple_strtol(buf, NULL, 10);                     \
522         if (val < 0 || val > 255)                               \
523                 return -EINVAL;                                 \
524         printk(KERN_INFO "Setting specified fan speed to %d\n", val);   \
525         data = val;                                             \
526         return n;                                               \
527 }
528
529 BUILD_SHOW_FUNC_INT(sensor1_temperature,         (read_reg(thermostat, TEMP_REG[1])))
530 BUILD_SHOW_FUNC_INT(sensor2_temperature,         (read_reg(thermostat, TEMP_REG[2])))
531 BUILD_SHOW_FUNC_INT(sensor1_limit,               thermostat->limits[1])
532 BUILD_SHOW_FUNC_INT(sensor2_limit,               thermostat->limits[2])
533 BUILD_SHOW_FUNC_STR(sensor1_location,            sensor_location[1])
534 BUILD_SHOW_FUNC_STR(sensor2_location,            sensor_location[2])
535
536 BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
537 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed,   0)
538 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed,   1)
539
540 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
541 BUILD_SHOW_FUNC_INT(limit_adjust,        limit_adjust)
542 BUILD_STORE_FUNC_DEG(limit_adjust,       thermostat)
543                 
544 static DEVICE_ATTR(sensor1_temperature, S_IRUGO,
545                    show_sensor1_temperature,NULL);
546 static DEVICE_ATTR(sensor2_temperature, S_IRUGO,
547                    show_sensor2_temperature,NULL);
548 static DEVICE_ATTR(sensor1_limit, S_IRUGO,
549                    show_sensor1_limit,  NULL);
550 static DEVICE_ATTR(sensor2_limit, S_IRUGO,
551                    show_sensor2_limit,  NULL);
552 static DEVICE_ATTR(sensor1_location, S_IRUGO,
553                    show_sensor1_location, NULL);
554 static DEVICE_ATTR(sensor2_location, S_IRUGO,
555                    show_sensor2_location, NULL);
556
557 static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
558                    show_specified_fan_speed,store_specified_fan_speed);
559
560 static DEVICE_ATTR(sensor1_fan_speed,   S_IRUGO,
561                    show_sensor1_fan_speed,      NULL);
562 static DEVICE_ATTR(sensor2_fan_speed,   S_IRUGO,
563                    show_sensor2_fan_speed,      NULL);
564
565 static DEVICE_ATTR(limit_adjust,        S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
566                    show_limit_adjust,   store_limit_adjust);
567
568
569 static int __init
570 thermostat_init(void)
571 {
572         struct device_node* np;
573         const u32 *prop;
574         int i = 0, offset = 0;
575
576         np = of_find_node_by_name(NULL, "fan");
577         if (!np)
578                 return -ENODEV;
579         if (of_device_is_compatible(np, "adt7460"))
580                 therm_type = ADT7460;
581         else if (of_device_is_compatible(np, "adt7467"))
582                 therm_type = ADT7467;
583         else {
584                 of_node_put(np);
585                 return -ENODEV;
586         }
587
588         prop = of_get_property(np, "hwsensor-params-version", NULL);
589         printk(KERN_INFO "adt746x: version %d (%ssupported)\n", *prop,
590                          (*prop == 1)?"":"un");
591         if (*prop != 1) {
592                 of_node_put(np);
593                 return -ENODEV;
594         }
595
596         prop = of_get_property(np, "reg", NULL);
597         if (!prop) {
598                 of_node_put(np);
599                 return -ENODEV;
600         }
601
602         /* look for bus either by path or using "reg" */
603         if (strstr(np->full_name, "/i2c-bus@") != NULL) {
604                 const char *tmp_bus = (strstr(np->full_name, "/i2c-bus@") + 9);
605                 therm_bus = tmp_bus[0]-'0';
606         } else {
607                 therm_bus = ((*prop) >> 8) & 0x0f;
608         }
609
610         therm_address = ((*prop) & 0xff) >> 1;
611
612         printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, "
613                          "limit_adjust: %d, fan_speed: %d\n",
614                          therm_bus, therm_address, limit_adjust, fan_speed);
615
616         if (of_get_property(np, "hwsensor-location", NULL)) {
617                 for (i = 0; i < 3; i++) {
618                         sensor_location[i] = of_get_property(np,
619                                         "hwsensor-location", NULL) + offset;
620
621                         if (sensor_location[i] == NULL)
622                                 sensor_location[i] = "";
623
624                         printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);
625                         offset += strlen(sensor_location[i]) + 1;
626                 }
627         } else {
628                 sensor_location[0] = "?";
629                 sensor_location[1] = "?";
630                 sensor_location[2] = "?";
631         }
632
633         of_dev = of_platform_device_create(np, "temperatures", NULL);
634         of_node_put(np);
635
636         if (of_dev == NULL) {
637                 printk(KERN_ERR "Can't register temperatures device !\n");
638                 return -ENODEV;
639         }
640
641 #ifndef CONFIG_I2C_POWERMAC
642         request_module("i2c-powermac");
643 #endif
644
645         return i2c_add_driver(&thermostat_driver);
646 }
647
648 static void thermostat_create_files(void)
649 {
650         int err;
651
652         err = device_create_file(&of_dev->dev, &dev_attr_sensor1_temperature);
653         err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_temperature);
654         err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_limit);
655         err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_limit);
656         err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_location);
657         err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_location);
658         err |= device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
659         err |= device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
660         err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
661         if(therm_type == ADT7460)
662                 err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_fan_speed);
663         if (err)
664                 printk(KERN_WARNING
665                         "Failed to create tempertaure attribute file(s).\n");
666 }
667
668 static void thermostat_remove_files(void)
669 {
670         if (of_dev) {
671                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_temperature);
672                 device_remove_file(&of_dev->dev, &dev_attr_sensor2_temperature);
673                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_limit);
674                 device_remove_file(&of_dev->dev, &dev_attr_sensor2_limit);
675                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_location);
676                 device_remove_file(&of_dev->dev, &dev_attr_sensor2_location);
677                 device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
678                 device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
679                 device_remove_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
680
681                 if(therm_type == ADT7460)
682                         device_remove_file(&of_dev->dev,
683                                            &dev_attr_sensor2_fan_speed);
684
685         }
686 }
687
688 static void __exit
689 thermostat_exit(void)
690 {
691         i2c_del_driver(&thermostat_driver);
692         of_device_unregister(of_dev);
693 }
694
695 module_init(thermostat_init);
696 module_exit(thermostat_exit);