xref: /linux/drivers/hwmon/it87.c (revision b454cc6636d254fbf6049b73e9560aee76fb04a3)
1 /*
2     it87.c - Part of lm_sensors, Linux kernel modules for hardware
3              monitoring.
4 
5     Supports: IT8705F  Super I/O chip w/LPC interface
6               IT8712F  Super I/O chip w/LPC interface
7               IT8716F  Super I/O chip w/LPC interface
8               IT8718F  Super I/O chip w/LPC interface
9               Sis950   A clone of the IT8705F
10 
11     Copyright (C) 2001 Chris Gauthron <chrisg@0-in.com>
12     Copyright (C) 2005-2006 Jean Delvare <khali@linux-fr.org>
13 
14     This program is free software; you can redistribute it and/or modify
15     it under the terms of the GNU General Public License as published by
16     the Free Software Foundation; either version 2 of the License, or
17     (at your option) any later version.
18 
19     This program is distributed in the hope that it will be useful,
20     but WITHOUT ANY WARRANTY; without even the implied warranty of
21     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22     GNU General Public License for more details.
23 
24     You should have received a copy of the GNU General Public License
25     along with this program; if not, write to the Free Software
26     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
27 */
28 
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/slab.h>
32 #include <linux/jiffies.h>
33 #include <linux/i2c.h>
34 #include <linux/i2c-isa.h>
35 #include <linux/hwmon.h>
36 #include <linux/hwmon-sysfs.h>
37 #include <linux/hwmon-vid.h>
38 #include <linux/err.h>
39 #include <linux/mutex.h>
40 #include <linux/sysfs.h>
41 #include <asm/io.h>
42 
43 
44 static unsigned short isa_address;
45 enum chips { it87, it8712, it8716, it8718 };
46 
47 #define	REG	0x2e	/* The register to read/write */
48 #define	DEV	0x07	/* Register: Logical device select */
49 #define	VAL	0x2f	/* The value to read/write */
50 #define PME	0x04	/* The device with the fan registers in it */
51 #define GPIO	0x07	/* The device with the IT8718F VID value in it */
52 #define	DEVID	0x20	/* Register: Device ID */
53 #define	DEVREV	0x22	/* Register: Device Revision */
54 
55 static inline int
56 superio_inb(int reg)
57 {
58 	outb(reg, REG);
59 	return inb(VAL);
60 }
61 
62 static int superio_inw(int reg)
63 {
64 	int val;
65 	outb(reg++, REG);
66 	val = inb(VAL) << 8;
67 	outb(reg, REG);
68 	val |= inb(VAL);
69 	return val;
70 }
71 
72 static inline void
73 superio_select(int ldn)
74 {
75 	outb(DEV, REG);
76 	outb(ldn, VAL);
77 }
78 
79 static inline void
80 superio_enter(void)
81 {
82 	outb(0x87, REG);
83 	outb(0x01, REG);
84 	outb(0x55, REG);
85 	outb(0x55, REG);
86 }
87 
88 static inline void
89 superio_exit(void)
90 {
91 	outb(0x02, REG);
92 	outb(0x02, VAL);
93 }
94 
95 /* Logical device 4 registers */
96 #define IT8712F_DEVID 0x8712
97 #define IT8705F_DEVID 0x8705
98 #define IT8716F_DEVID 0x8716
99 #define IT8718F_DEVID 0x8718
100 #define IT87_ACT_REG  0x30
101 #define IT87_BASE_REG 0x60
102 
103 /* Logical device 7 registers (IT8712F and later) */
104 #define IT87_SIO_PINX2_REG	0x2c	/* Pin selection */
105 #define IT87_SIO_VID_REG	0xfc	/* VID value */
106 
107 /* Update battery voltage after every reading if true */
108 static int update_vbat;
109 
110 /* Not all BIOSes properly configure the PWM registers */
111 static int fix_pwm_polarity;
112 
113 /* Values read from Super-I/O config space */
114 static u16 chip_type;
115 static u8 vid_value;
116 
117 /* Many IT87 constants specified below */
118 
119 /* Length of ISA address segment */
120 #define IT87_EXTENT 8
121 
122 /* Where are the ISA address/data registers relative to the base address */
123 #define IT87_ADDR_REG_OFFSET 5
124 #define IT87_DATA_REG_OFFSET 6
125 
126 /*----- The IT87 registers -----*/
127 
128 #define IT87_REG_CONFIG        0x00
129 
130 #define IT87_REG_ALARM1        0x01
131 #define IT87_REG_ALARM2        0x02
132 #define IT87_REG_ALARM3        0x03
133 
134 /* The IT8718F has the VID value in a different register, in Super-I/O
135    configuration space. */
136 #define IT87_REG_VID           0x0a
137 /* Warning: register 0x0b is used for something completely different in
138    new chips/revisions. I suspect only 16-bit tachometer mode will work
139    for these. */
140 #define IT87_REG_FAN_DIV       0x0b
141 #define IT87_REG_FAN_16BIT     0x0c
142 
143 /* Monitors: 9 voltage (0 to 7, battery), 3 temp (1 to 3), 3 fan (1 to 3) */
144 
145 #define IT87_REG_FAN(nr)       (0x0d + (nr))
146 #define IT87_REG_FAN_MIN(nr)   (0x10 + (nr))
147 #define IT87_REG_FANX(nr)      (0x18 + (nr))
148 #define IT87_REG_FANX_MIN(nr)  (0x1b + (nr))
149 #define IT87_REG_FAN_MAIN_CTRL 0x13
150 #define IT87_REG_FAN_CTL       0x14
151 #define IT87_REG_PWM(nr)       (0x15 + (nr))
152 
153 #define IT87_REG_VIN(nr)       (0x20 + (nr))
154 #define IT87_REG_TEMP(nr)      (0x29 + (nr))
155 
156 #define IT87_REG_VIN_MAX(nr)   (0x30 + (nr) * 2)
157 #define IT87_REG_VIN_MIN(nr)   (0x31 + (nr) * 2)
158 #define IT87_REG_TEMP_HIGH(nr) (0x40 + (nr) * 2)
159 #define IT87_REG_TEMP_LOW(nr)  (0x41 + (nr) * 2)
160 
161 #define IT87_REG_VIN_ENABLE    0x50
162 #define IT87_REG_TEMP_ENABLE   0x51
163 
164 #define IT87_REG_CHIPID        0x58
165 
166 #define IN_TO_REG(val)  (SENSORS_LIMIT((((val) + 8)/16),0,255))
167 #define IN_FROM_REG(val) ((val) * 16)
168 
169 static inline u8 FAN_TO_REG(long rpm, int div)
170 {
171 	if (rpm == 0)
172 		return 255;
173 	rpm = SENSORS_LIMIT(rpm, 1, 1000000);
174 	return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1,
175 			     254);
176 }
177 
178 static inline u16 FAN16_TO_REG(long rpm)
179 {
180 	if (rpm == 0)
181 		return 0xffff;
182 	return SENSORS_LIMIT((1350000 + rpm) / (rpm * 2), 1, 0xfffe);
183 }
184 
185 #define FAN_FROM_REG(val,div) ((val)==0?-1:(val)==255?0:1350000/((val)*(div)))
186 /* The divider is fixed to 2 in 16-bit mode */
187 #define FAN16_FROM_REG(val) ((val)==0?-1:(val)==0xffff?0:1350000/((val)*2))
188 
189 #define TEMP_TO_REG(val) (SENSORS_LIMIT(((val)<0?(((val)-500)/1000):\
190 					((val)+500)/1000),-128,127))
191 #define TEMP_FROM_REG(val) (((val)>0x80?(val)-0x100:(val))*1000)
192 
193 #define PWM_TO_REG(val)   ((val) >> 1)
194 #define PWM_FROM_REG(val) (((val)&0x7f) << 1)
195 
196 static int DIV_TO_REG(int val)
197 {
198 	int answer = 0;
199 	while (answer < 7 && (val >>= 1))
200 		answer++;
201 	return answer;
202 }
203 #define DIV_FROM_REG(val) (1 << (val))
204 
205 
206 /* For each registered IT87, we need to keep some data in memory. That
207    data is pointed to by it87_list[NR]->data. The structure itself is
208    dynamically allocated, at the same time when a new it87 client is
209    allocated. */
210 struct it87_data {
211 	struct i2c_client client;
212 	struct class_device *class_dev;
213 	struct mutex lock;
214 	enum chips type;
215 
216 	struct mutex update_lock;
217 	char valid;		/* !=0 if following fields are valid */
218 	unsigned long last_updated;	/* In jiffies */
219 
220 	u8 in[9];		/* Register value */
221 	u8 in_max[8];		/* Register value */
222 	u8 in_min[8];		/* Register value */
223 	u8 has_fan;		/* Bitfield, fans enabled */
224 	u16 fan[3];		/* Register values, possibly combined */
225 	u16 fan_min[3];		/* Register values, possibly combined */
226 	u8 temp[3];		/* Register value */
227 	u8 temp_high[3];	/* Register value */
228 	u8 temp_low[3];		/* Register value */
229 	u8 sensor;		/* Register value */
230 	u8 fan_div[3];		/* Register encoding, shifted right */
231 	u8 vid;			/* Register encoding, combined */
232 	u8 vrm;
233 	u32 alarms;		/* Register encoding, combined */
234 	u8 fan_main_ctrl;	/* Register value */
235 	u8 manual_pwm_ctl[3];   /* manual PWM value set by user */
236 };
237 
238 
239 static int it87_detect(struct i2c_adapter *adapter);
240 static int it87_detach_client(struct i2c_client *client);
241 
242 static int it87_read_value(struct i2c_client *client, u8 reg);
243 static void it87_write_value(struct i2c_client *client, u8 reg, u8 value);
244 static struct it87_data *it87_update_device(struct device *dev);
245 static int it87_check_pwm(struct i2c_client *client);
246 static void it87_init_client(struct i2c_client *client, struct it87_data *data);
247 
248 
249 static struct i2c_driver it87_isa_driver = {
250 	.driver = {
251 		.owner	= THIS_MODULE,
252 		.name	= "it87-isa",
253 	},
254 	.attach_adapter	= it87_detect,
255 	.detach_client	= it87_detach_client,
256 };
257 
258 
259 static ssize_t show_in(struct device *dev, struct device_attribute *attr,
260 		char *buf)
261 {
262 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
263 	int nr = sensor_attr->index;
264 
265 	struct it87_data *data = it87_update_device(dev);
266 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[nr]));
267 }
268 
269 static ssize_t show_in_min(struct device *dev, struct device_attribute *attr,
270 		char *buf)
271 {
272 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
273 	int nr = sensor_attr->index;
274 
275 	struct it87_data *data = it87_update_device(dev);
276 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[nr]));
277 }
278 
279 static ssize_t show_in_max(struct device *dev, struct device_attribute *attr,
280 		char *buf)
281 {
282 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
283 	int nr = sensor_attr->index;
284 
285 	struct it87_data *data = it87_update_device(dev);
286 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[nr]));
287 }
288 
289 static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
290 		const char *buf, size_t count)
291 {
292 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
293 	int nr = sensor_attr->index;
294 
295 	struct i2c_client *client = to_i2c_client(dev);
296 	struct it87_data *data = i2c_get_clientdata(client);
297 	unsigned long val = simple_strtoul(buf, NULL, 10);
298 
299 	mutex_lock(&data->update_lock);
300 	data->in_min[nr] = IN_TO_REG(val);
301 	it87_write_value(client, IT87_REG_VIN_MIN(nr),
302 			data->in_min[nr]);
303 	mutex_unlock(&data->update_lock);
304 	return count;
305 }
306 static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
307 		const char *buf, size_t count)
308 {
309 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
310 	int nr = sensor_attr->index;
311 
312 	struct i2c_client *client = to_i2c_client(dev);
313 	struct it87_data *data = i2c_get_clientdata(client);
314 	unsigned long val = simple_strtoul(buf, NULL, 10);
315 
316 	mutex_lock(&data->update_lock);
317 	data->in_max[nr] = IN_TO_REG(val);
318 	it87_write_value(client, IT87_REG_VIN_MAX(nr),
319 			data->in_max[nr]);
320 	mutex_unlock(&data->update_lock);
321 	return count;
322 }
323 
324 #define show_in_offset(offset)					\
325 static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
326 		show_in, NULL, offset);
327 
328 #define limit_in_offset(offset)					\
329 static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
330 		show_in_min, set_in_min, offset);		\
331 static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
332 		show_in_max, set_in_max, offset);
333 
334 show_in_offset(0);
335 limit_in_offset(0);
336 show_in_offset(1);
337 limit_in_offset(1);
338 show_in_offset(2);
339 limit_in_offset(2);
340 show_in_offset(3);
341 limit_in_offset(3);
342 show_in_offset(4);
343 limit_in_offset(4);
344 show_in_offset(5);
345 limit_in_offset(5);
346 show_in_offset(6);
347 limit_in_offset(6);
348 show_in_offset(7);
349 limit_in_offset(7);
350 show_in_offset(8);
351 
352 /* 3 temperatures */
353 static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
354 		char *buf)
355 {
356 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
357 	int nr = sensor_attr->index;
358 
359 	struct it87_data *data = it87_update_device(dev);
360 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
361 }
362 static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr,
363 		char *buf)
364 {
365 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
366 	int nr = sensor_attr->index;
367 
368 	struct it87_data *data = it87_update_device(dev);
369 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_high[nr]));
370 }
371 static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
372 		char *buf)
373 {
374 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
375 	int nr = sensor_attr->index;
376 
377 	struct it87_data *data = it87_update_device(dev);
378 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_low[nr]));
379 }
380 static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
381 		const char *buf, size_t count)
382 {
383 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
384 	int nr = sensor_attr->index;
385 
386 	struct i2c_client *client = to_i2c_client(dev);
387 	struct it87_data *data = i2c_get_clientdata(client);
388 	int val = simple_strtol(buf, NULL, 10);
389 
390 	mutex_lock(&data->update_lock);
391 	data->temp_high[nr] = TEMP_TO_REG(val);
392 	it87_write_value(client, IT87_REG_TEMP_HIGH(nr), data->temp_high[nr]);
393 	mutex_unlock(&data->update_lock);
394 	return count;
395 }
396 static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
397 		const char *buf, size_t count)
398 {
399 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
400 	int nr = sensor_attr->index;
401 
402 	struct i2c_client *client = to_i2c_client(dev);
403 	struct it87_data *data = i2c_get_clientdata(client);
404 	int val = simple_strtol(buf, NULL, 10);
405 
406 	mutex_lock(&data->update_lock);
407 	data->temp_low[nr] = TEMP_TO_REG(val);
408 	it87_write_value(client, IT87_REG_TEMP_LOW(nr), data->temp_low[nr]);
409 	mutex_unlock(&data->update_lock);
410 	return count;
411 }
412 #define show_temp_offset(offset)					\
413 static SENSOR_DEVICE_ATTR(temp##offset##_input, S_IRUGO,		\
414 		show_temp, NULL, offset - 1);				\
415 static SENSOR_DEVICE_ATTR(temp##offset##_max, S_IRUGO | S_IWUSR,	\
416 		show_temp_max, set_temp_max, offset - 1);		\
417 static SENSOR_DEVICE_ATTR(temp##offset##_min, S_IRUGO | S_IWUSR,	\
418 		show_temp_min, set_temp_min, offset - 1);
419 
420 show_temp_offset(1);
421 show_temp_offset(2);
422 show_temp_offset(3);
423 
424 static ssize_t show_sensor(struct device *dev, struct device_attribute *attr,
425 		char *buf)
426 {
427 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
428 	int nr = sensor_attr->index;
429 
430 	struct it87_data *data = it87_update_device(dev);
431 	u8 reg = data->sensor; /* In case the value is updated while we use it */
432 
433 	if (reg & (1 << nr))
434 		return sprintf(buf, "3\n");  /* thermal diode */
435 	if (reg & (8 << nr))
436 		return sprintf(buf, "2\n");  /* thermistor */
437 	return sprintf(buf, "0\n");      /* disabled */
438 }
439 static ssize_t set_sensor(struct device *dev, struct device_attribute *attr,
440 		const char *buf, size_t count)
441 {
442 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
443 	int nr = sensor_attr->index;
444 
445 	struct i2c_client *client = to_i2c_client(dev);
446 	struct it87_data *data = i2c_get_clientdata(client);
447 	int val = simple_strtol(buf, NULL, 10);
448 
449 	mutex_lock(&data->update_lock);
450 
451 	data->sensor &= ~(1 << nr);
452 	data->sensor &= ~(8 << nr);
453 	/* 3 = thermal diode; 2 = thermistor; 0 = disabled */
454 	if (val == 3)
455 	    data->sensor |= 1 << nr;
456 	else if (val == 2)
457 	    data->sensor |= 8 << nr;
458 	else if (val != 0) {
459 		mutex_unlock(&data->update_lock);
460 		return -EINVAL;
461 	}
462 	it87_write_value(client, IT87_REG_TEMP_ENABLE, data->sensor);
463 	mutex_unlock(&data->update_lock);
464 	return count;
465 }
466 #define show_sensor_offset(offset)					\
467 static SENSOR_DEVICE_ATTR(temp##offset##_type, S_IRUGO | S_IWUSR,	\
468 		show_sensor, set_sensor, offset - 1);
469 
470 show_sensor_offset(1);
471 show_sensor_offset(2);
472 show_sensor_offset(3);
473 
474 /* 3 Fans */
475 static ssize_t show_fan(struct device *dev, struct device_attribute *attr,
476 		char *buf)
477 {
478 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
479 	int nr = sensor_attr->index;
480 
481 	struct it87_data *data = it87_update_device(dev);
482 	return sprintf(buf,"%d\n", FAN_FROM_REG(data->fan[nr],
483 				DIV_FROM_REG(data->fan_div[nr])));
484 }
485 static ssize_t show_fan_min(struct device *dev, struct device_attribute *attr,
486 		char *buf)
487 {
488 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
489 	int nr = sensor_attr->index;
490 
491 	struct it87_data *data = it87_update_device(dev);
492 	return sprintf(buf,"%d\n",
493 		FAN_FROM_REG(data->fan_min[nr], DIV_FROM_REG(data->fan_div[nr])));
494 }
495 static ssize_t show_fan_div(struct device *dev, struct device_attribute *attr,
496 		char *buf)
497 {
498 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
499 	int nr = sensor_attr->index;
500 
501 	struct it87_data *data = it87_update_device(dev);
502 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
503 }
504 static ssize_t show_pwm_enable(struct device *dev, struct device_attribute *attr,
505 		char *buf)
506 {
507 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
508 	int nr = sensor_attr->index;
509 
510 	struct it87_data *data = it87_update_device(dev);
511 	return sprintf(buf,"%d\n", (data->fan_main_ctrl & (1 << nr)) ? 1 : 0);
512 }
513 static ssize_t show_pwm(struct device *dev, struct device_attribute *attr,
514 		char *buf)
515 {
516 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
517 	int nr = sensor_attr->index;
518 
519 	struct it87_data *data = it87_update_device(dev);
520 	return sprintf(buf,"%d\n", data->manual_pwm_ctl[nr]);
521 }
522 static ssize_t set_fan_min(struct device *dev, struct device_attribute *attr,
523 		const char *buf, size_t count)
524 {
525 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
526 	int nr = sensor_attr->index;
527 
528 	struct i2c_client *client = to_i2c_client(dev);
529 	struct it87_data *data = i2c_get_clientdata(client);
530 	int val = simple_strtol(buf, NULL, 10);
531 	u8 reg = it87_read_value(client, IT87_REG_FAN_DIV);
532 
533 	mutex_lock(&data->update_lock);
534 	switch (nr) {
535 	case 0: data->fan_div[nr] = reg & 0x07; break;
536 	case 1: data->fan_div[nr] = (reg >> 3) & 0x07; break;
537 	case 2: data->fan_div[nr] = (reg & 0x40) ? 3 : 1; break;
538 	}
539 
540 	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
541 	it87_write_value(client, IT87_REG_FAN_MIN(nr), data->fan_min[nr]);
542 	mutex_unlock(&data->update_lock);
543 	return count;
544 }
545 static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr,
546 		const char *buf, size_t count)
547 {
548 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
549 	int nr = sensor_attr->index;
550 
551 	struct i2c_client *client = to_i2c_client(dev);
552 	struct it87_data *data = i2c_get_clientdata(client);
553 	unsigned long val = simple_strtoul(buf, NULL, 10);
554 	int min;
555 	u8 old;
556 
557 	mutex_lock(&data->update_lock);
558 	old = it87_read_value(client, IT87_REG_FAN_DIV);
559 
560 	/* Save fan min limit */
561 	min = FAN_FROM_REG(data->fan_min[nr], DIV_FROM_REG(data->fan_div[nr]));
562 
563 	switch (nr) {
564 	case 0:
565 	case 1:
566 		data->fan_div[nr] = DIV_TO_REG(val);
567 		break;
568 	case 2:
569 		if (val < 8)
570 			data->fan_div[nr] = 1;
571 		else
572 			data->fan_div[nr] = 3;
573 	}
574 	val = old & 0x80;
575 	val |= (data->fan_div[0] & 0x07);
576 	val |= (data->fan_div[1] & 0x07) << 3;
577 	if (data->fan_div[2] == 3)
578 		val |= 0x1 << 6;
579 	it87_write_value(client, IT87_REG_FAN_DIV, val);
580 
581 	/* Restore fan min limit */
582 	data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
583 	it87_write_value(client, IT87_REG_FAN_MIN(nr), data->fan_min[nr]);
584 
585 	mutex_unlock(&data->update_lock);
586 	return count;
587 }
588 static ssize_t set_pwm_enable(struct device *dev,
589 		struct device_attribute *attr, const char *buf, size_t count)
590 {
591 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
592 	int nr = sensor_attr->index;
593 
594 	struct i2c_client *client = to_i2c_client(dev);
595 	struct it87_data *data = i2c_get_clientdata(client);
596 	int val = simple_strtol(buf, NULL, 10);
597 
598 	mutex_lock(&data->update_lock);
599 
600 	if (val == 0) {
601 		int tmp;
602 		/* make sure the fan is on when in on/off mode */
603 		tmp = it87_read_value(client, IT87_REG_FAN_CTL);
604 		it87_write_value(client, IT87_REG_FAN_CTL, tmp | (1 << nr));
605 		/* set on/off mode */
606 		data->fan_main_ctrl &= ~(1 << nr);
607 		it87_write_value(client, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
608 	} else if (val == 1) {
609 		/* set SmartGuardian mode */
610 		data->fan_main_ctrl |= (1 << nr);
611 		it87_write_value(client, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
612 		/* set saved pwm value, clear FAN_CTLX PWM mode bit */
613 		it87_write_value(client, IT87_REG_PWM(nr), PWM_TO_REG(data->manual_pwm_ctl[nr]));
614 	} else {
615 		mutex_unlock(&data->update_lock);
616 		return -EINVAL;
617 	}
618 
619 	mutex_unlock(&data->update_lock);
620 	return count;
621 }
622 static ssize_t set_pwm(struct device *dev, struct device_attribute *attr,
623 		const char *buf, size_t count)
624 {
625 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
626 	int nr = sensor_attr->index;
627 
628 	struct i2c_client *client = to_i2c_client(dev);
629 	struct it87_data *data = i2c_get_clientdata(client);
630 	int val = simple_strtol(buf, NULL, 10);
631 
632 	if (val < 0 || val > 255)
633 		return -EINVAL;
634 
635 	mutex_lock(&data->update_lock);
636 	data->manual_pwm_ctl[nr] = val;
637 	if (data->fan_main_ctrl & (1 << nr))
638 		it87_write_value(client, IT87_REG_PWM(nr), PWM_TO_REG(data->manual_pwm_ctl[nr]));
639 	mutex_unlock(&data->update_lock);
640 	return count;
641 }
642 
643 #define show_fan_offset(offset)					\
644 static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO,		\
645 		show_fan, NULL, offset - 1);			\
646 static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR, \
647 		show_fan_min, set_fan_min, offset - 1);		\
648 static SENSOR_DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR, \
649 		show_fan_div, set_fan_div, offset - 1);
650 
651 show_fan_offset(1);
652 show_fan_offset(2);
653 show_fan_offset(3);
654 
655 #define show_pwm_offset(offset)						\
656 static SENSOR_DEVICE_ATTR(pwm##offset##_enable, S_IRUGO | S_IWUSR,	\
657 		show_pwm_enable, set_pwm_enable, offset - 1);		\
658 static SENSOR_DEVICE_ATTR(pwm##offset, S_IRUGO | S_IWUSR,		\
659 		show_pwm, set_pwm, offset - 1);
660 
661 show_pwm_offset(1);
662 show_pwm_offset(2);
663 show_pwm_offset(3);
664 
665 /* A different set of callbacks for 16-bit fans */
666 static ssize_t show_fan16(struct device *dev, struct device_attribute *attr,
667 		char *buf)
668 {
669 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
670 	int nr = sensor_attr->index;
671 	struct it87_data *data = it87_update_device(dev);
672 	return sprintf(buf, "%d\n", FAN16_FROM_REG(data->fan[nr]));
673 }
674 
675 static ssize_t show_fan16_min(struct device *dev, struct device_attribute *attr,
676 		char *buf)
677 {
678 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
679 	int nr = sensor_attr->index;
680 	struct it87_data *data = it87_update_device(dev);
681 	return sprintf(buf, "%d\n", FAN16_FROM_REG(data->fan_min[nr]));
682 }
683 
684 static ssize_t set_fan16_min(struct device *dev, struct device_attribute *attr,
685 		const char *buf, size_t count)
686 {
687 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
688 	int nr = sensor_attr->index;
689 	struct i2c_client *client = to_i2c_client(dev);
690 	struct it87_data *data = i2c_get_clientdata(client);
691 	int val = simple_strtol(buf, NULL, 10);
692 
693 	mutex_lock(&data->update_lock);
694 	data->fan_min[nr] = FAN16_TO_REG(val);
695 	it87_write_value(client, IT87_REG_FAN_MIN(nr),
696 			 data->fan_min[nr] & 0xff);
697 	it87_write_value(client, IT87_REG_FANX_MIN(nr),
698 			 data->fan_min[nr] >> 8);
699 	mutex_unlock(&data->update_lock);
700 	return count;
701 }
702 
703 /* We want to use the same sysfs file names as 8-bit fans, but we need
704    different variable names, so we have to use SENSOR_ATTR instead of
705    SENSOR_DEVICE_ATTR. */
706 #define show_fan16_offset(offset) \
707 static struct sensor_device_attribute sensor_dev_attr_fan##offset##_input16 \
708 	= SENSOR_ATTR(fan##offset##_input, S_IRUGO,		\
709 		show_fan16, NULL, offset - 1);			\
710 static struct sensor_device_attribute sensor_dev_attr_fan##offset##_min16 \
711 	= SENSOR_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,	\
712 		show_fan16_min, set_fan16_min, offset - 1)
713 
714 show_fan16_offset(1);
715 show_fan16_offset(2);
716 show_fan16_offset(3);
717 
718 /* Alarms */
719 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
720 {
721 	struct it87_data *data = it87_update_device(dev);
722 	return sprintf(buf, "%u\n", data->alarms);
723 }
724 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
725 
726 static ssize_t
727 show_vrm_reg(struct device *dev, struct device_attribute *attr, char *buf)
728 {
729 	struct it87_data *data = it87_update_device(dev);
730 	return sprintf(buf, "%u\n", data->vrm);
731 }
732 static ssize_t
733 store_vrm_reg(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
734 {
735 	struct i2c_client *client = to_i2c_client(dev);
736 	struct it87_data *data = i2c_get_clientdata(client);
737 	u32 val;
738 
739 	val = simple_strtoul(buf, NULL, 10);
740 	data->vrm = val;
741 
742 	return count;
743 }
744 static DEVICE_ATTR(vrm, S_IRUGO | S_IWUSR, show_vrm_reg, store_vrm_reg);
745 
746 static ssize_t
747 show_vid_reg(struct device *dev, struct device_attribute *attr, char *buf)
748 {
749 	struct it87_data *data = it87_update_device(dev);
750 	return sprintf(buf, "%ld\n", (long) vid_from_reg(data->vid, data->vrm));
751 }
752 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid_reg, NULL);
753 
754 static struct attribute *it87_attributes[] = {
755 	&sensor_dev_attr_in0_input.dev_attr.attr,
756 	&sensor_dev_attr_in1_input.dev_attr.attr,
757 	&sensor_dev_attr_in2_input.dev_attr.attr,
758 	&sensor_dev_attr_in3_input.dev_attr.attr,
759 	&sensor_dev_attr_in4_input.dev_attr.attr,
760 	&sensor_dev_attr_in5_input.dev_attr.attr,
761 	&sensor_dev_attr_in6_input.dev_attr.attr,
762 	&sensor_dev_attr_in7_input.dev_attr.attr,
763 	&sensor_dev_attr_in8_input.dev_attr.attr,
764 	&sensor_dev_attr_in0_min.dev_attr.attr,
765 	&sensor_dev_attr_in1_min.dev_attr.attr,
766 	&sensor_dev_attr_in2_min.dev_attr.attr,
767 	&sensor_dev_attr_in3_min.dev_attr.attr,
768 	&sensor_dev_attr_in4_min.dev_attr.attr,
769 	&sensor_dev_attr_in5_min.dev_attr.attr,
770 	&sensor_dev_attr_in6_min.dev_attr.attr,
771 	&sensor_dev_attr_in7_min.dev_attr.attr,
772 	&sensor_dev_attr_in0_max.dev_attr.attr,
773 	&sensor_dev_attr_in1_max.dev_attr.attr,
774 	&sensor_dev_attr_in2_max.dev_attr.attr,
775 	&sensor_dev_attr_in3_max.dev_attr.attr,
776 	&sensor_dev_attr_in4_max.dev_attr.attr,
777 	&sensor_dev_attr_in5_max.dev_attr.attr,
778 	&sensor_dev_attr_in6_max.dev_attr.attr,
779 	&sensor_dev_attr_in7_max.dev_attr.attr,
780 
781 	&sensor_dev_attr_temp1_input.dev_attr.attr,
782 	&sensor_dev_attr_temp2_input.dev_attr.attr,
783 	&sensor_dev_attr_temp3_input.dev_attr.attr,
784 	&sensor_dev_attr_temp1_max.dev_attr.attr,
785 	&sensor_dev_attr_temp2_max.dev_attr.attr,
786 	&sensor_dev_attr_temp3_max.dev_attr.attr,
787 	&sensor_dev_attr_temp1_min.dev_attr.attr,
788 	&sensor_dev_attr_temp2_min.dev_attr.attr,
789 	&sensor_dev_attr_temp3_min.dev_attr.attr,
790 	&sensor_dev_attr_temp1_type.dev_attr.attr,
791 	&sensor_dev_attr_temp2_type.dev_attr.attr,
792 	&sensor_dev_attr_temp3_type.dev_attr.attr,
793 
794 	&dev_attr_alarms.attr,
795 	NULL
796 };
797 
798 static const struct attribute_group it87_group = {
799 	.attrs = it87_attributes,
800 };
801 
802 static struct attribute *it87_attributes_opt[] = {
803 	&sensor_dev_attr_fan1_input16.dev_attr.attr,
804 	&sensor_dev_attr_fan1_min16.dev_attr.attr,
805 	&sensor_dev_attr_fan2_input16.dev_attr.attr,
806 	&sensor_dev_attr_fan2_min16.dev_attr.attr,
807 	&sensor_dev_attr_fan3_input16.dev_attr.attr,
808 	&sensor_dev_attr_fan3_min16.dev_attr.attr,
809 
810 	&sensor_dev_attr_fan1_input.dev_attr.attr,
811 	&sensor_dev_attr_fan1_min.dev_attr.attr,
812 	&sensor_dev_attr_fan1_div.dev_attr.attr,
813 	&sensor_dev_attr_fan2_input.dev_attr.attr,
814 	&sensor_dev_attr_fan2_min.dev_attr.attr,
815 	&sensor_dev_attr_fan2_div.dev_attr.attr,
816 	&sensor_dev_attr_fan3_input.dev_attr.attr,
817 	&sensor_dev_attr_fan3_min.dev_attr.attr,
818 	&sensor_dev_attr_fan3_div.dev_attr.attr,
819 
820 	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
821 	&sensor_dev_attr_pwm2_enable.dev_attr.attr,
822 	&sensor_dev_attr_pwm3_enable.dev_attr.attr,
823 	&sensor_dev_attr_pwm1.dev_attr.attr,
824 	&sensor_dev_attr_pwm2.dev_attr.attr,
825 	&sensor_dev_attr_pwm3.dev_attr.attr,
826 
827 	&dev_attr_vrm.attr,
828 	&dev_attr_cpu0_vid.attr,
829 	NULL
830 };
831 
832 static const struct attribute_group it87_group_opt = {
833 	.attrs = it87_attributes_opt,
834 };
835 
836 /* SuperIO detection - will change isa_address if a chip is found */
837 static int __init it87_find(unsigned short *address)
838 {
839 	int err = -ENODEV;
840 
841 	superio_enter();
842 	chip_type = superio_inw(DEVID);
843 	if (chip_type != IT8712F_DEVID
844 	 && chip_type != IT8716F_DEVID
845 	 && chip_type != IT8718F_DEVID
846 	 && chip_type != IT8705F_DEVID)
847 	 	goto exit;
848 
849 	superio_select(PME);
850 	if (!(superio_inb(IT87_ACT_REG) & 0x01)) {
851 		pr_info("it87: Device not activated, skipping\n");
852 		goto exit;
853 	}
854 
855 	*address = superio_inw(IT87_BASE_REG) & ~(IT87_EXTENT - 1);
856 	if (*address == 0) {
857 		pr_info("it87: Base address not set, skipping\n");
858 		goto exit;
859 	}
860 
861 	err = 0;
862 	pr_info("it87: Found IT%04xF chip at 0x%x, revision %d\n",
863 		chip_type, *address, superio_inb(DEVREV) & 0x0f);
864 
865 	/* Read GPIO config and VID value from LDN 7 (GPIO) */
866 	if (chip_type != IT8705F_DEVID) {
867 		int reg;
868 
869 		superio_select(GPIO);
870 		if (chip_type == it8718)
871 			vid_value = superio_inb(IT87_SIO_VID_REG);
872 
873 		reg = superio_inb(IT87_SIO_PINX2_REG);
874 		if (reg & (1 << 0))
875 			pr_info("it87: in3 is VCC (+5V)\n");
876 		if (reg & (1 << 1))
877 			pr_info("it87: in7 is VCCH (+5V Stand-By)\n");
878 	}
879 
880 exit:
881 	superio_exit();
882 	return err;
883 }
884 
885 /* This function is called by i2c_probe */
886 static int it87_detect(struct i2c_adapter *adapter)
887 {
888 	struct i2c_client *new_client;
889 	struct it87_data *data;
890 	int err = 0;
891 	const char *name;
892 	int enable_pwm_interface;
893 
894 	/* Reserve the ISA region */
895 	if (!request_region(isa_address, IT87_EXTENT,
896 			    it87_isa_driver.driver.name)){
897 		err = -EBUSY;
898 		goto ERROR0;
899 	}
900 
901 	if (!(data = kzalloc(sizeof(struct it87_data), GFP_KERNEL))) {
902 		err = -ENOMEM;
903 		goto ERROR1;
904 	}
905 
906 	new_client = &data->client;
907 	mutex_init(&data->lock);
908 	i2c_set_clientdata(new_client, data);
909 	new_client->addr = isa_address;
910 	new_client->adapter = adapter;
911 	new_client->driver = &it87_isa_driver;
912 
913 	/* Now, we do the remaining detection. */
914 	if ((it87_read_value(new_client, IT87_REG_CONFIG) & 0x80)
915 	 || it87_read_value(new_client, IT87_REG_CHIPID) != 0x90) {
916 		err = -ENODEV;
917 		goto ERROR2;
918 	}
919 
920 	/* Determine the chip type. */
921 	switch (chip_type) {
922 	case IT8712F_DEVID:
923 		data->type = it8712;
924 		name = "it8712";
925 		break;
926 	case IT8716F_DEVID:
927 		data->type = it8716;
928 		name = "it8716";
929 		break;
930 	case IT8718F_DEVID:
931 		data->type = it8718;
932 		name = "it8718";
933 		break;
934 	default:
935 		data->type = it87;
936 		name = "it87";
937 	}
938 
939 	/* Fill in the remaining client fields and put it into the global list */
940 	strlcpy(new_client->name, name, I2C_NAME_SIZE);
941 	mutex_init(&data->update_lock);
942 
943 	/* Tell the I2C layer a new client has arrived */
944 	if ((err = i2c_attach_client(new_client)))
945 		goto ERROR2;
946 
947 	/* Check PWM configuration */
948 	enable_pwm_interface = it87_check_pwm(new_client);
949 
950 	/* Initialize the IT87 chip */
951 	it87_init_client(new_client, data);
952 
953 	/* Register sysfs hooks */
954 	if ((err = sysfs_create_group(&new_client->dev.kobj, &it87_group)))
955 		goto ERROR3;
956 
957 	/* Do not create fan files for disabled fans */
958 	if (data->type == it8716 || data->type == it8718) {
959 		/* 16-bit tachometers */
960 		if (data->has_fan & (1 << 0)) {
961 			if ((err = device_create_file(&new_client->dev,
962 			     &sensor_dev_attr_fan1_input16.dev_attr))
963 			 || (err = device_create_file(&new_client->dev,
964 			     &sensor_dev_attr_fan1_min16.dev_attr)))
965 				goto ERROR4;
966 		}
967 		if (data->has_fan & (1 << 1)) {
968 			if ((err = device_create_file(&new_client->dev,
969 			     &sensor_dev_attr_fan2_input16.dev_attr))
970 			 || (err = device_create_file(&new_client->dev,
971 			     &sensor_dev_attr_fan2_min16.dev_attr)))
972 				goto ERROR4;
973 		}
974 		if (data->has_fan & (1 << 2)) {
975 			if ((err = device_create_file(&new_client->dev,
976 			     &sensor_dev_attr_fan3_input16.dev_attr))
977 			 || (err = device_create_file(&new_client->dev,
978 			     &sensor_dev_attr_fan3_min16.dev_attr)))
979 				goto ERROR4;
980 		}
981 	} else {
982 		/* 8-bit tachometers with clock divider */
983 		if (data->has_fan & (1 << 0)) {
984 			if ((err = device_create_file(&new_client->dev,
985 			     &sensor_dev_attr_fan1_input.dev_attr))
986 			 || (err = device_create_file(&new_client->dev,
987 			     &sensor_dev_attr_fan1_min.dev_attr))
988 			 || (err = device_create_file(&new_client->dev,
989 			     &sensor_dev_attr_fan1_div.dev_attr)))
990 				goto ERROR4;
991 		}
992 		if (data->has_fan & (1 << 1)) {
993 			if ((err = device_create_file(&new_client->dev,
994 			     &sensor_dev_attr_fan2_input.dev_attr))
995 			 || (err = device_create_file(&new_client->dev,
996 			     &sensor_dev_attr_fan2_min.dev_attr))
997 			 || (err = device_create_file(&new_client->dev,
998 			     &sensor_dev_attr_fan2_div.dev_attr)))
999 				goto ERROR4;
1000 		}
1001 		if (data->has_fan & (1 << 2)) {
1002 			if ((err = device_create_file(&new_client->dev,
1003 			     &sensor_dev_attr_fan3_input.dev_attr))
1004 			 || (err = device_create_file(&new_client->dev,
1005 			     &sensor_dev_attr_fan3_min.dev_attr))
1006 			 || (err = device_create_file(&new_client->dev,
1007 			     &sensor_dev_attr_fan3_div.dev_attr)))
1008 				goto ERROR4;
1009 		}
1010 	}
1011 
1012 	if (enable_pwm_interface) {
1013 		if ((err = device_create_file(&new_client->dev,
1014 		     &sensor_dev_attr_pwm1_enable.dev_attr))
1015 		 || (err = device_create_file(&new_client->dev,
1016 		     &sensor_dev_attr_pwm2_enable.dev_attr))
1017 		 || (err = device_create_file(&new_client->dev,
1018 		     &sensor_dev_attr_pwm3_enable.dev_attr))
1019 		 || (err = device_create_file(&new_client->dev,
1020 		     &sensor_dev_attr_pwm1.dev_attr))
1021 		 || (err = device_create_file(&new_client->dev,
1022 		     &sensor_dev_attr_pwm2.dev_attr))
1023 		 || (err = device_create_file(&new_client->dev,
1024 		     &sensor_dev_attr_pwm3.dev_attr)))
1025 			goto ERROR4;
1026 	}
1027 
1028 	if (data->type == it8712 || data->type == it8716
1029 	 || data->type == it8718) {
1030 		data->vrm = vid_which_vrm();
1031 		/* VID reading from Super-I/O config space if available */
1032 		data->vid = vid_value;
1033 		if ((err = device_create_file(&new_client->dev,
1034 		     &dev_attr_vrm))
1035 		 || (err = device_create_file(&new_client->dev,
1036 		     &dev_attr_cpu0_vid)))
1037 			goto ERROR4;
1038 	}
1039 
1040 	data->class_dev = hwmon_device_register(&new_client->dev);
1041 	if (IS_ERR(data->class_dev)) {
1042 		err = PTR_ERR(data->class_dev);
1043 		goto ERROR4;
1044 	}
1045 
1046 	return 0;
1047 
1048 ERROR4:
1049 	sysfs_remove_group(&new_client->dev.kobj, &it87_group);
1050 	sysfs_remove_group(&new_client->dev.kobj, &it87_group_opt);
1051 ERROR3:
1052 	i2c_detach_client(new_client);
1053 ERROR2:
1054 	kfree(data);
1055 ERROR1:
1056 	release_region(isa_address, IT87_EXTENT);
1057 ERROR0:
1058 	return err;
1059 }
1060 
1061 static int it87_detach_client(struct i2c_client *client)
1062 {
1063 	struct it87_data *data = i2c_get_clientdata(client);
1064 	int err;
1065 
1066 	hwmon_device_unregister(data->class_dev);
1067 	sysfs_remove_group(&client->dev.kobj, &it87_group);
1068 	sysfs_remove_group(&client->dev.kobj, &it87_group_opt);
1069 
1070 	if ((err = i2c_detach_client(client)))
1071 		return err;
1072 
1073 	release_region(client->addr, IT87_EXTENT);
1074 	kfree(data);
1075 
1076 	return 0;
1077 }
1078 
1079 /* ISA access must be locked explicitly!
1080    We ignore the IT87 BUSY flag at this moment - it could lead to deadlocks,
1081    would slow down the IT87 access and should not be necessary. */
1082 static int it87_read_value(struct i2c_client *client, u8 reg)
1083 {
1084 	struct it87_data *data = i2c_get_clientdata(client);
1085 	int res;
1086 
1087 	mutex_lock(&data->lock);
1088 	outb_p(reg, client->addr + IT87_ADDR_REG_OFFSET);
1089 	res = inb_p(client->addr + IT87_DATA_REG_OFFSET);
1090 	mutex_unlock(&data->lock);
1091 
1092 	return res;
1093 }
1094 
1095 /* ISA access must be locked explicitly!
1096    We ignore the IT87 BUSY flag at this moment - it could lead to deadlocks,
1097    would slow down the IT87 access and should not be necessary. */
1098 static void it87_write_value(struct i2c_client *client, u8 reg, u8 value)
1099 {
1100 	struct it87_data *data = i2c_get_clientdata(client);
1101 
1102 	mutex_lock(&data->lock);
1103 	outb_p(reg, client->addr + IT87_ADDR_REG_OFFSET);
1104 	outb_p(value, client->addr + IT87_DATA_REG_OFFSET);
1105 	mutex_unlock(&data->lock);
1106 }
1107 
1108 /* Return 1 if and only if the PWM interface is safe to use */
1109 static int it87_check_pwm(struct i2c_client *client)
1110 {
1111 	/* Some BIOSes fail to correctly configure the IT87 fans. All fans off
1112 	 * and polarity set to active low is sign that this is the case so we
1113 	 * disable pwm control to protect the user. */
1114 	int tmp = it87_read_value(client, IT87_REG_FAN_CTL);
1115 	if ((tmp & 0x87) == 0) {
1116 		if (fix_pwm_polarity) {
1117 			/* The user asks us to attempt a chip reconfiguration.
1118 			 * This means switching to active high polarity and
1119 			 * inverting all fan speed values. */
1120 			int i;
1121 			u8 pwm[3];
1122 
1123 			for (i = 0; i < 3; i++)
1124 				pwm[i] = it87_read_value(client,
1125 							 IT87_REG_PWM(i));
1126 
1127 			/* If any fan is in automatic pwm mode, the polarity
1128 			 * might be correct, as suspicious as it seems, so we
1129 			 * better don't change anything (but still disable the
1130 			 * PWM interface). */
1131 			if (!((pwm[0] | pwm[1] | pwm[2]) & 0x80)) {
1132 				dev_info(&client->dev, "Reconfiguring PWM to "
1133 					 "active high polarity\n");
1134 				it87_write_value(client, IT87_REG_FAN_CTL,
1135 						 tmp | 0x87);
1136 				for (i = 0; i < 3; i++)
1137 					it87_write_value(client,
1138 							 IT87_REG_PWM(i),
1139 							 0x7f & ~pwm[i]);
1140 				return 1;
1141 			}
1142 
1143 			dev_info(&client->dev, "PWM configuration is "
1144 				 "too broken to be fixed\n");
1145 		}
1146 
1147 		dev_info(&client->dev, "Detected broken BIOS "
1148 			 "defaults, disabling PWM interface\n");
1149 		return 0;
1150 	} else if (fix_pwm_polarity) {
1151 		dev_info(&client->dev, "PWM configuration looks "
1152 			 "sane, won't touch\n");
1153 	}
1154 
1155 	return 1;
1156 }
1157 
1158 /* Called when we have found a new IT87. */
1159 static void it87_init_client(struct i2c_client *client, struct it87_data *data)
1160 {
1161 	int tmp, i;
1162 
1163 	/* initialize to sane defaults:
1164 	 * - if the chip is in manual pwm mode, this will be overwritten with
1165 	 *   the actual settings on the chip (so in this case, initialization
1166 	 *   is not needed)
1167 	 * - if in automatic or on/off mode, we could switch to manual mode,
1168 	 *   read the registers and set manual_pwm_ctl accordingly, but currently
1169 	 *   this is not implemented, so we initialize to something sane */
1170 	for (i = 0; i < 3; i++) {
1171 		data->manual_pwm_ctl[i] = 0xff;
1172 	}
1173 
1174 	/* Some chips seem to have default value 0xff for all limit
1175 	 * registers. For low voltage limits it makes no sense and triggers
1176 	 * alarms, so change to 0 instead. For high temperature limits, it
1177 	 * means -1 degree C, which surprisingly doesn't trigger an alarm,
1178 	 * but is still confusing, so change to 127 degrees C. */
1179 	for (i = 0; i < 8; i++) {
1180 		tmp = it87_read_value(client, IT87_REG_VIN_MIN(i));
1181 		if (tmp == 0xff)
1182 			it87_write_value(client, IT87_REG_VIN_MIN(i), 0);
1183 	}
1184 	for (i = 0; i < 3; i++) {
1185 		tmp = it87_read_value(client, IT87_REG_TEMP_HIGH(i));
1186 		if (tmp == 0xff)
1187 			it87_write_value(client, IT87_REG_TEMP_HIGH(i), 127);
1188 	}
1189 
1190 	/* Check if temperature channnels are reset manually or by some reason */
1191 	tmp = it87_read_value(client, IT87_REG_TEMP_ENABLE);
1192 	if ((tmp & 0x3f) == 0) {
1193 		/* Temp1,Temp3=thermistor; Temp2=thermal diode */
1194 		tmp = (tmp & 0xc0) | 0x2a;
1195 		it87_write_value(client, IT87_REG_TEMP_ENABLE, tmp);
1196 	}
1197 	data->sensor = tmp;
1198 
1199 	/* Check if voltage monitors are reset manually or by some reason */
1200 	tmp = it87_read_value(client, IT87_REG_VIN_ENABLE);
1201 	if ((tmp & 0xff) == 0) {
1202 		/* Enable all voltage monitors */
1203 		it87_write_value(client, IT87_REG_VIN_ENABLE, 0xff);
1204 	}
1205 
1206 	/* Check if tachometers are reset manually or by some reason */
1207 	data->fan_main_ctrl = it87_read_value(client, IT87_REG_FAN_MAIN_CTRL);
1208 	if ((data->fan_main_ctrl & 0x70) == 0) {
1209 		/* Enable all fan tachometers */
1210 		data->fan_main_ctrl |= 0x70;
1211 		it87_write_value(client, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
1212 	}
1213 	data->has_fan = (data->fan_main_ctrl >> 4) & 0x07;
1214 
1215 	/* Set tachometers to 16-bit mode if needed */
1216 	if (data->type == it8716 || data->type == it8718) {
1217 		tmp = it87_read_value(client, IT87_REG_FAN_16BIT);
1218 		if (~tmp & 0x07 & data->has_fan) {
1219 			dev_dbg(&client->dev,
1220 				"Setting fan1-3 to 16-bit mode\n");
1221 			it87_write_value(client, IT87_REG_FAN_16BIT,
1222 					 tmp | 0x07);
1223 		}
1224 	}
1225 
1226 	/* Set current fan mode registers and the default settings for the
1227 	 * other mode registers */
1228 	for (i = 0; i < 3; i++) {
1229 		if (data->fan_main_ctrl & (1 << i)) {
1230 			/* pwm mode */
1231 			tmp = it87_read_value(client, IT87_REG_PWM(i));
1232 			if (tmp & 0x80) {
1233 				/* automatic pwm - not yet implemented, but
1234 				 * leave the settings made by the BIOS alone
1235 				 * until a change is requested via the sysfs
1236 				 * interface */
1237 			} else {
1238 				/* manual pwm */
1239 				data->manual_pwm_ctl[i] = PWM_FROM_REG(tmp);
1240 			}
1241 		}
1242  	}
1243 
1244 	/* Start monitoring */
1245 	it87_write_value(client, IT87_REG_CONFIG,
1246 			 (it87_read_value(client, IT87_REG_CONFIG) & 0x36)
1247 			 | (update_vbat ? 0x41 : 0x01));
1248 }
1249 
1250 static struct it87_data *it87_update_device(struct device *dev)
1251 {
1252 	struct i2c_client *client = to_i2c_client(dev);
1253 	struct it87_data *data = i2c_get_clientdata(client);
1254 	int i;
1255 
1256 	mutex_lock(&data->update_lock);
1257 
1258 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
1259 	    || !data->valid) {
1260 
1261 		if (update_vbat) {
1262 			/* Cleared after each update, so reenable.  Value
1263 		 	  returned by this read will be previous value */
1264 			it87_write_value(client, IT87_REG_CONFIG,
1265 			   it87_read_value(client, IT87_REG_CONFIG) | 0x40);
1266 		}
1267 		for (i = 0; i <= 7; i++) {
1268 			data->in[i] =
1269 			    it87_read_value(client, IT87_REG_VIN(i));
1270 			data->in_min[i] =
1271 			    it87_read_value(client, IT87_REG_VIN_MIN(i));
1272 			data->in_max[i] =
1273 			    it87_read_value(client, IT87_REG_VIN_MAX(i));
1274 		}
1275 		/* in8 (battery) has no limit registers */
1276 		data->in[8] =
1277 		    it87_read_value(client, IT87_REG_VIN(8));
1278 
1279 		for (i = 0; i < 3; i++) {
1280 			/* Skip disabled fans */
1281 			if (!(data->has_fan & (1 << i)))
1282 				continue;
1283 
1284 			data->fan_min[i] =
1285 			    it87_read_value(client, IT87_REG_FAN_MIN(i));
1286 			data->fan[i] = it87_read_value(client,
1287 				       IT87_REG_FAN(i));
1288 			/* Add high byte if in 16-bit mode */
1289 			if (data->type == it8716 || data->type == it8718) {
1290 				data->fan[i] |= it87_read_value(client,
1291 						IT87_REG_FANX(i)) << 8;
1292 				data->fan_min[i] |= it87_read_value(client,
1293 						IT87_REG_FANX_MIN(i)) << 8;
1294 			}
1295 		}
1296 		for (i = 0; i < 3; i++) {
1297 			data->temp[i] =
1298 			    it87_read_value(client, IT87_REG_TEMP(i));
1299 			data->temp_high[i] =
1300 			    it87_read_value(client, IT87_REG_TEMP_HIGH(i));
1301 			data->temp_low[i] =
1302 			    it87_read_value(client, IT87_REG_TEMP_LOW(i));
1303 		}
1304 
1305 		/* Newer chips don't have clock dividers */
1306 		if ((data->has_fan & 0x07) && data->type != it8716
1307 		 && data->type != it8718) {
1308 			i = it87_read_value(client, IT87_REG_FAN_DIV);
1309 			data->fan_div[0] = i & 0x07;
1310 			data->fan_div[1] = (i >> 3) & 0x07;
1311 			data->fan_div[2] = (i & 0x40) ? 3 : 1;
1312 		}
1313 
1314 		data->alarms =
1315 			it87_read_value(client, IT87_REG_ALARM1) |
1316 			(it87_read_value(client, IT87_REG_ALARM2) << 8) |
1317 			(it87_read_value(client, IT87_REG_ALARM3) << 16);
1318 		data->fan_main_ctrl = it87_read_value(client, IT87_REG_FAN_MAIN_CTRL);
1319 
1320 		data->sensor = it87_read_value(client, IT87_REG_TEMP_ENABLE);
1321 		/* The 8705 does not have VID capability */
1322 		if (data->type == it8712 || data->type == it8716) {
1323 			data->vid = it87_read_value(client, IT87_REG_VID);
1324 			/* The older IT8712F revisions had only 5 VID pins,
1325 			   but we assume it is always safe to read 6 bits. */
1326 			data->vid &= 0x3f;
1327 		}
1328 		data->last_updated = jiffies;
1329 		data->valid = 1;
1330 	}
1331 
1332 	mutex_unlock(&data->update_lock);
1333 
1334 	return data;
1335 }
1336 
1337 static int __init sm_it87_init(void)
1338 {
1339 	int res;
1340 
1341 	if ((res = it87_find(&isa_address)))
1342 		return res;
1343 	return i2c_isa_add_driver(&it87_isa_driver);
1344 }
1345 
1346 static void __exit sm_it87_exit(void)
1347 {
1348 	i2c_isa_del_driver(&it87_isa_driver);
1349 }
1350 
1351 
1352 MODULE_AUTHOR("Chris Gauthron <chrisg@0-in.com>, "
1353 	      "Jean Delvare <khali@linux-fr.org>");
1354 MODULE_DESCRIPTION("IT8705F/8712F/8716F/8718F, SiS950 driver");
1355 module_param(update_vbat, bool, 0);
1356 MODULE_PARM_DESC(update_vbat, "Update vbat if set else return powerup value");
1357 module_param(fix_pwm_polarity, bool, 0);
1358 MODULE_PARM_DESC(fix_pwm_polarity, "Force PWM polarity to active high (DANGEROUS)");
1359 MODULE_LICENSE("GPL");
1360 
1361 module_init(sm_it87_init);
1362 module_exit(sm_it87_exit);
1363