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 
28 #include <asm/prom.h>
29 #include <asm/machdep.h>
30 #include <asm/io.h>
31 #include <asm/system.h>
32 #include <asm/sections.h>
33 #include <asm/of_platform.h>
34 
35 #undef DEBUG
36 
37 #define CONFIG_REG   0x40
38 #define MANUAL_MASK  0xe0
39 #define AUTO_MASK    0x20
40 
41 static u8 TEMP_REG[3]    = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
42 static u8 LIMIT_REG[3]   = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
43 static u8 MANUAL_MODE[2] = {0x5c, 0x5d};
44 static u8 REM_CONTROL[2] = {0x00, 0x40};
45 static u8 FAN_SPEED[2]   = {0x28, 0x2a};
46 static u8 FAN_SPD_SET[2] = {0x30, 0x31};
47 
48 static u8 default_limits_local[3] = {70, 50, 70};    /* local, sensor1, sensor2 */
49 static u8 default_limits_chip[3] = {80, 65, 80};    /* local, sensor1, sensor2 */
50 static const char *sensor_location[3];
51 
52 static int limit_adjust;
53 static int fan_speed = -1;
54 static int verbose;
55 
56 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
57 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
58 		   "Powerbook G4 Alu");
59 MODULE_LICENSE("GPL");
60 
61 module_param(limit_adjust, int, 0644);
62 MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
63 		 "by N degrees.");
64 
65 module_param(fan_speed, int, 0644);
66 MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "
67 		 "(default 64)");
68 
69 module_param(verbose, bool, 0);
70 MODULE_PARM_DESC(verbose,"Verbose log operations "
71 		 "(default 0)");
72 
73 struct thermostat {
74 	struct i2c_client	clt;
75 	u8			temps[3];
76 	u8			cached_temp[3];
77 	u8			initial_limits[3];
78 	u8			limits[3];
79 	int			last_speed[2];
80 	int			last_var[2];
81 };
82 
83 static enum {ADT7460, ADT7467} therm_type;
84 static int therm_bus, therm_address;
85 static struct of_device * of_dev;
86 static struct thermostat* thermostat;
87 static struct task_struct *thread_therm = NULL;
88 
89 static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
90 				 int busno);
91 
92 static void write_both_fan_speed(struct thermostat *th, int speed);
93 static void write_fan_speed(struct thermostat *th, int speed, int fan);
94 
95 static int
96 write_reg(struct thermostat* th, int reg, u8 data)
97 {
98 	u8 tmp[2];
99 	int rc;
100 
101 	tmp[0] = reg;
102 	tmp[1] = data;
103 	rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
104 	if (rc < 0)
105 		return rc;
106 	if (rc != 2)
107 		return -ENODEV;
108 	return 0;
109 }
110 
111 static int
112 read_reg(struct thermostat* th, int reg)
113 {
114 	u8 reg_addr, data;
115 	int rc;
116 
117 	reg_addr = (u8)reg;
118 	rc = i2c_master_send(&th->clt, &reg_addr, 1);
119 	if (rc < 0)
120 		return rc;
121 	if (rc != 1)
122 		return -ENODEV;
123 	rc = i2c_master_recv(&th->clt, (char *)&data, 1);
124 	if (rc < 0)
125 		return rc;
126 	return data;
127 }
128 
129 static int
130 attach_thermostat(struct i2c_adapter *adapter)
131 {
132 	unsigned long bus_no;
133 
134 	if (strncmp(adapter->name, "uni-n", 5))
135 		return -ENODEV;
136 	bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
137 	if (bus_no != therm_bus)
138 		return -ENODEV;
139 	return attach_one_thermostat(adapter, therm_address, bus_no);
140 }
141 
142 static int
143 detach_thermostat(struct i2c_adapter *adapter)
144 {
145 	struct thermostat* th;
146 	int i;
147 
148 	if (thermostat == NULL)
149 		return 0;
150 
151 	th = thermostat;
152 
153 	if (thread_therm != NULL) {
154 		kthread_stop(thread_therm);
155 	}
156 
157 	printk(KERN_INFO "adt746x: Putting max temperatures back from "
158 			 "%d, %d, %d to %d, %d, %d\n",
159 		th->limits[0], th->limits[1], th->limits[2],
160 		th->initial_limits[0], th->initial_limits[1],
161 		th->initial_limits[2]);
162 
163 	for (i = 0; i < 3; i++)
164 		write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
165 
166 	write_both_fan_speed(th, -1);
167 
168 	i2c_detach_client(&th->clt);
169 
170 	thermostat = NULL;
171 
172 	kfree(th);
173 
174 	return 0;
175 }
176 
177 static struct i2c_driver thermostat_driver = {
178 	.driver = {
179 		.name	= "therm_adt746x",
180 	},
181 	.attach_adapter	= attach_thermostat,
182 	.detach_adapter	= detach_thermostat,
183 };
184 
185 static int read_fan_speed(struct thermostat *th, u8 addr)
186 {
187 	u8 tmp[2];
188 	u16 res;
189 
190 	/* should start with low byte */
191 	tmp[1] = read_reg(th, addr);
192 	tmp[0] = read_reg(th, addr + 1);
193 
194 	res = tmp[1] + (tmp[0] << 8);
195 	/* "a value of 0xffff means that the fan has stopped" */
196 	return (res == 0xffff ? 0 : (90000*60)/res);
197 }
198 
199 static void write_both_fan_speed(struct thermostat *th, int speed)
200 {
201 	write_fan_speed(th, speed, 0);
202 	if (therm_type == ADT7460)
203 		write_fan_speed(th, speed, 1);
204 }
205 
206 static void write_fan_speed(struct thermostat *th, int speed, int fan)
207 {
208 	u8 manual;
209 
210 	if (speed > 0xff)
211 		speed = 0xff;
212 	else if (speed < -1)
213 		speed = 0;
214 
215 	if (therm_type == ADT7467 && fan == 1)
216 		return;
217 
218 	if (th->last_speed[fan] != speed) {
219 		if (verbose) {
220 			if (speed == -1)
221 				printk(KERN_DEBUG "adt746x: Setting speed to automatic "
222 					"for %s fan.\n", sensor_location[fan+1]);
223 			else
224 				printk(KERN_DEBUG "adt746x: Setting speed to %d "
225 					"for %s fan.\n", speed, sensor_location[fan+1]);
226 		}
227 	} else
228 		return;
229 
230 	if (speed >= 0) {
231 		manual = read_reg(th, MANUAL_MODE[fan]);
232 		write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK);
233 		write_reg(th, FAN_SPD_SET[fan], speed);
234 	} else {
235 		/* back to automatic */
236 		if(therm_type == ADT7460) {
237 			manual = read_reg(th,
238 				MANUAL_MODE[fan]) & (~MANUAL_MASK);
239 
240 			write_reg(th,
241 				MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
242 		} else {
243 			manual = read_reg(th, MANUAL_MODE[fan]);
244 			write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
245 		}
246 	}
247 
248 	th->last_speed[fan] = speed;
249 }
250 
251 static void read_sensors(struct thermostat *th)
252 {
253 	int i = 0;
254 
255 	for (i = 0; i < 3; i++)
256 		th->temps[i]  = read_reg(th, TEMP_REG[i]);
257 }
258 
259 #ifdef DEBUG
260 static void display_stats(struct thermostat *th)
261 {
262 	if (th->temps[0] != th->cached_temp[0]
263 	||  th->temps[1] != th->cached_temp[1]
264 	||  th->temps[2] != th->cached_temp[2]) {
265 		printk(KERN_INFO "adt746x: Temperature infos:"
266 				 " thermostats: %d,%d,%d;"
267 				 " limits: %d,%d,%d;"
268 				 " fan speed: %d RPM\n",
269 				 th->temps[0], th->temps[1], th->temps[2],
270 				 th->limits[0],  th->limits[1],  th->limits[2],
271 				 read_fan_speed(th, FAN_SPEED[0]));
272 	}
273 	th->cached_temp[0] = th->temps[0];
274 	th->cached_temp[1] = th->temps[1];
275 	th->cached_temp[2] = th->temps[2];
276 }
277 #endif
278 
279 static void update_fans_speed (struct thermostat *th)
280 {
281 	int lastvar = 0; /* last variation, for iBook */
282 	int i = 0;
283 
284 	/* we don't care about local sensor, so we start at sensor 1 */
285 	for (i = 1; i < 3; i++) {
286 		int started = 0;
287 		int fan_number = (therm_type == ADT7460 && i == 2);
288 		int var = th->temps[i] - th->limits[i];
289 
290 		if (var > -1) {
291 			int step = (255 - fan_speed) / 7;
292 			int new_speed = 0;
293 
294 			/* hysteresis : change fan speed only if variation is
295 			 * more than two degrees */
296 			if (abs(var - th->last_var[fan_number]) < 2)
297 				continue;
298 
299 			started = 1;
300 			new_speed = fan_speed + ((var-1)*step);
301 
302 			if (new_speed < fan_speed)
303 				new_speed = fan_speed;
304 			if (new_speed > 255)
305 				new_speed = 255;
306 
307 			if (verbose)
308 				printk(KERN_DEBUG "adt746x: Setting fans speed to %d "
309 						 "(limit exceeded by %d on %s) \n",
310 						new_speed, var,
311 						sensor_location[fan_number+1]);
312 			write_both_fan_speed(th, new_speed);
313 			th->last_var[fan_number] = var;
314 		} else if (var < -2) {
315 			/* don't stop fan if sensor2 is cold and sensor1 is not
316 			 * so cold (lastvar >= -1) */
317 			if (i == 2 && lastvar < -1) {
318 				if (th->last_speed[fan_number] != 0)
319 					if (verbose)
320 						printk(KERN_DEBUG "adt746x: Stopping "
321 							"fans.\n");
322 				write_both_fan_speed(th, 0);
323 			}
324 		}
325 
326 		lastvar = var;
327 
328 		if (started)
329 			return; /* we don't want to re-stop the fan
330 				* if sensor1 is heating and sensor2 is not */
331 	}
332 }
333 
334 static int monitor_task(void *arg)
335 {
336 	struct thermostat* th = arg;
337 
338 	set_freezable();
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 = kzalloc(sizeof(struct thermostat), GFP_KERNEL);
383 	if (!th)
384 		return -ENOMEM;
385 
386 	th->clt.addr = addr;
387 	th->clt.adapter = adapter;
388 	th->clt.driver = &thermostat_driver;
389 	strcpy(th->clt.name, "thermostat");
390 
391 	rc = read_reg(th, 0);
392 	if (rc < 0) {
393 		printk(KERN_ERR "adt746x: Thermostat failed to read config "
394 				"from bus %d !\n",
395 				busno);
396 		kfree(th);
397 		return -ENODEV;
398 	}
399 
400 	/* force manual control to start the fan quieter */
401 	if (fan_speed == -1)
402 		fan_speed = 64;
403 
404 	if(therm_type == ADT7460) {
405 		printk(KERN_INFO "adt746x: ADT7460 initializing\n");
406 		/* The 7460 needs to be started explicitly */
407 		write_reg(th, CONFIG_REG, 1);
408 	} else
409 		printk(KERN_INFO "adt746x: ADT7467 initializing\n");
410 
411 	for (i = 0; i < 3; i++) {
412 		th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
413 		set_limit(th, i);
414 	}
415 
416 	printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
417 			 " to %d, %d, %d\n",
418 			 th->initial_limits[0], th->initial_limits[1],
419 			 th->initial_limits[2], th->limits[0], th->limits[1],
420 			 th->limits[2]);
421 
422 	thermostat = th;
423 
424 	if (i2c_attach_client(&th->clt)) {
425 		printk(KERN_INFO "adt746x: Thermostat failed to attach "
426 				 "client !\n");
427 		thermostat = NULL;
428 		kfree(th);
429 		return -ENODEV;
430 	}
431 
432 	/* be sure to really write fan speed the first time */
433 	th->last_speed[0] = -2;
434 	th->last_speed[1] = -2;
435 	th->last_var[0] = -80;
436 	th->last_var[1] = -80;
437 
438 	if (fan_speed != -1) {
439 		/* manual mode, stop fans */
440 		write_both_fan_speed(th, 0);
441 	} else {
442 		/* automatic mode */
443 		write_both_fan_speed(th, -1);
444 	}
445 
446 	thread_therm = kthread_run(monitor_task, th, "kfand");
447 
448 	if (thread_therm == ERR_PTR(-ENOMEM)) {
449 		printk(KERN_INFO "adt746x: Kthread creation failed\n");
450 		thread_therm = NULL;
451 		return -ENOMEM;
452 	}
453 
454 	return 0;
455 }
456 
457 /*
458  * Now, unfortunately, sysfs doesn't give us a nice void * we could
459  * pass around to the attribute functions, so we don't really have
460  * choice but implement a bunch of them...
461  *
462  * FIXME, it does now...
463  */
464 #define BUILD_SHOW_FUNC_INT(name, data)				\
465 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)	\
466 {								\
467 	return sprintf(buf, "%d\n", data);			\
468 }
469 
470 #define BUILD_SHOW_FUNC_STR(name, data)				\
471 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)       \
472 {								\
473 	return sprintf(buf, "%s\n", data);			\
474 }
475 
476 #define BUILD_SHOW_FUNC_FAN(name, data)				\
477 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)       \
478 {								\
479 	return sprintf(buf, "%d (%d rpm)\n", 			\
480 		thermostat->last_speed[data],			\
481 		read_fan_speed(thermostat, FAN_SPEED[data])	\
482 		);						\
483 }
484 
485 #define BUILD_STORE_FUNC_DEG(name, data)			\
486 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
487 {								\
488 	int val;						\
489 	int i;							\
490 	val = simple_strtol(buf, NULL, 10);			\
491 	printk(KERN_INFO "Adjusting limits by %d degrees\n", val);	\
492 	limit_adjust = val;					\
493 	for (i=0; i < 3; i++)					\
494 		set_limit(thermostat, i);			\
495 	return n;						\
496 }
497 
498 #define BUILD_STORE_FUNC_INT(name, data)			\
499 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
500 {								\
501 	u32 val;						\
502 	val = simple_strtoul(buf, NULL, 10);			\
503 	if (val < 0 || val > 255)				\
504 		return -EINVAL;					\
505 	printk(KERN_INFO "Setting specified fan speed to %d\n", val);	\
506 	data = val;						\
507 	return n;						\
508 }
509 
510 BUILD_SHOW_FUNC_INT(sensor1_temperature,	 (read_reg(thermostat, TEMP_REG[1])))
511 BUILD_SHOW_FUNC_INT(sensor2_temperature,	 (read_reg(thermostat, TEMP_REG[2])))
512 BUILD_SHOW_FUNC_INT(sensor1_limit,		 thermostat->limits[1])
513 BUILD_SHOW_FUNC_INT(sensor2_limit,		 thermostat->limits[2])
514 BUILD_SHOW_FUNC_STR(sensor1_location,		 sensor_location[1])
515 BUILD_SHOW_FUNC_STR(sensor2_location,		 sensor_location[2])
516 
517 BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
518 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed,	 0)
519 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed,	 1)
520 
521 BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
522 BUILD_SHOW_FUNC_INT(limit_adjust,	 limit_adjust)
523 BUILD_STORE_FUNC_DEG(limit_adjust,	 thermostat)
524 
525 static DEVICE_ATTR(sensor1_temperature,	S_IRUGO,
526 		   show_sensor1_temperature,NULL);
527 static DEVICE_ATTR(sensor2_temperature,	S_IRUGO,
528 		   show_sensor2_temperature,NULL);
529 static DEVICE_ATTR(sensor1_limit, S_IRUGO,
530 		   show_sensor1_limit,	NULL);
531 static DEVICE_ATTR(sensor2_limit, S_IRUGO,
532 		   show_sensor2_limit,	NULL);
533 static DEVICE_ATTR(sensor1_location, S_IRUGO,
534 		   show_sensor1_location, NULL);
535 static DEVICE_ATTR(sensor2_location, S_IRUGO,
536 		   show_sensor2_location, NULL);
537 
538 static DEVICE_ATTR(specified_fan_speed,	S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
539 		   show_specified_fan_speed,store_specified_fan_speed);
540 
541 static DEVICE_ATTR(sensor1_fan_speed,	S_IRUGO,
542 		   show_sensor1_fan_speed,	NULL);
543 static DEVICE_ATTR(sensor2_fan_speed,	S_IRUGO,
544 		   show_sensor2_fan_speed,	NULL);
545 
546 static DEVICE_ATTR(limit_adjust,	S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
547 		   show_limit_adjust,	store_limit_adjust);
548 
549 
550 static int __init
551 thermostat_init(void)
552 {
553 	struct device_node* np;
554 	const u32 *prop;
555 	int i = 0, offset = 0;
556 	int err;
557 
558 	np = of_find_node_by_name(NULL, "fan");
559 	if (!np)
560 		return -ENODEV;
561 	if (of_device_is_compatible(np, "adt7460"))
562 		therm_type = ADT7460;
563 	else if (of_device_is_compatible(np, "adt7467"))
564 		therm_type = ADT7467;
565 	else
566 		return -ENODEV;
567 
568 	prop = of_get_property(np, "hwsensor-params-version", NULL);
569 	printk(KERN_INFO "adt746x: version %d (%ssupported)\n", *prop,
570 			 (*prop == 1)?"":"un");
571 	if (*prop != 1)
572 		return -ENODEV;
573 
574 	prop = of_get_property(np, "reg", NULL);
575 	if (!prop)
576 		return -ENODEV;
577 
578 	/* look for bus either by path or using "reg" */
579 	if (strstr(np->full_name, "/i2c-bus@") != NULL) {
580 		const char *tmp_bus = (strstr(np->full_name, "/i2c-bus@") + 9);
581 		therm_bus = tmp_bus[0]-'0';
582 	} else {
583 		therm_bus = ((*prop) >> 8) & 0x0f;
584 	}
585 
586 	therm_address = ((*prop) & 0xff) >> 1;
587 
588 	printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, "
589 			 "limit_adjust: %d, fan_speed: %d\n",
590 			 therm_bus, therm_address, limit_adjust, fan_speed);
591 
592 	if (of_get_property(np, "hwsensor-location", NULL)) {
593 		for (i = 0; i < 3; i++) {
594 			sensor_location[i] = of_get_property(np,
595 					"hwsensor-location", NULL) + offset;
596 
597 			if (sensor_location[i] == NULL)
598 				sensor_location[i] = "";
599 
600 			printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);
601 			offset += strlen(sensor_location[i]) + 1;
602 		}
603 	} else {
604 		sensor_location[0] = "?";
605 		sensor_location[1] = "?";
606 		sensor_location[2] = "?";
607 	}
608 
609 	of_dev = of_platform_device_create(np, "temperatures", NULL);
610 
611 	if (of_dev == NULL) {
612 		printk(KERN_ERR "Can't register temperatures device !\n");
613 		return -ENODEV;
614 	}
615 
616 	err = device_create_file(&of_dev->dev, &dev_attr_sensor1_temperature);
617 	err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_temperature);
618 	err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_limit);
619 	err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_limit);
620 	err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_location);
621 	err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_location);
622 	err |= device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
623 	err |= device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
624 	err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
625 	if(therm_type == ADT7460)
626 		err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_fan_speed);
627 	if (err)
628 		printk(KERN_WARNING
629 			"Failed to create tempertaure attribute file(s).\n");
630 
631 #ifndef CONFIG_I2C_POWERMAC
632 	request_module("i2c-powermac");
633 #endif
634 
635 	return i2c_add_driver(&thermostat_driver);
636 }
637 
638 static void __exit
639 thermostat_exit(void)
640 {
641 	if (of_dev) {
642 		device_remove_file(&of_dev->dev, &dev_attr_sensor1_temperature);
643 		device_remove_file(&of_dev->dev, &dev_attr_sensor2_temperature);
644 		device_remove_file(&of_dev->dev, &dev_attr_sensor1_limit);
645 		device_remove_file(&of_dev->dev, &dev_attr_sensor2_limit);
646 		device_remove_file(&of_dev->dev, &dev_attr_sensor1_location);
647 		device_remove_file(&of_dev->dev, &dev_attr_sensor2_location);
648 		device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
649 		device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
650 		device_remove_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
651 
652 		if(therm_type == ADT7460)
653 			device_remove_file(&of_dev->dev,
654 					   &dev_attr_sensor2_fan_speed);
655 
656 		of_device_unregister(of_dev);
657 	}
658 	i2c_del_driver(&thermostat_driver);
659 }
660 
661 module_init(thermostat_init);
662 module_exit(thermostat_exit);
663