xref: /openbmc/linux/drivers/hwmon/w83l786ng.c (revision ca55b2fe)
1 /*
2  * w83l786ng.c - Linux kernel driver for hardware monitoring
3  * Copyright (c) 2007 Kevin Lo <kevlo@kevlo.org>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation - version 2.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301 USA.
18  */
19 
20 /*
21  * Supports following chips:
22  *
23  * Chip		#vin	#fanin	#pwm	#temp	wchipid	vendid	i2c	ISA
24  * w83l786ng	3	2	2	2	0x7b	0x5ca3	yes	no
25  */
26 
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/slab.h>
30 #include <linux/i2c.h>
31 #include <linux/hwmon.h>
32 #include <linux/hwmon-vid.h>
33 #include <linux/hwmon-sysfs.h>
34 #include <linux/err.h>
35 #include <linux/mutex.h>
36 #include <linux/jiffies.h>
37 
38 /* Addresses to scan */
39 static const unsigned short normal_i2c[] = { 0x2e, 0x2f, I2C_CLIENT_END };
40 
41 /* Insmod parameters */
42 
43 static bool reset;
44 module_param(reset, bool, 0);
45 MODULE_PARM_DESC(reset, "Set to 1 to reset chip, not recommended");
46 
47 #define W83L786NG_REG_IN_MIN(nr)	(0x2C + (nr) * 2)
48 #define W83L786NG_REG_IN_MAX(nr)	(0x2B + (nr) * 2)
49 #define W83L786NG_REG_IN(nr)		((nr) + 0x20)
50 
51 #define W83L786NG_REG_FAN(nr)		((nr) + 0x28)
52 #define W83L786NG_REG_FAN_MIN(nr)	((nr) + 0x3B)
53 
54 #define W83L786NG_REG_CONFIG		0x40
55 #define W83L786NG_REG_ALARM1		0x41
56 #define W83L786NG_REG_ALARM2		0x42
57 #define W83L786NG_REG_GPIO_EN		0x47
58 #define W83L786NG_REG_MAN_ID2		0x4C
59 #define W83L786NG_REG_MAN_ID1		0x4D
60 #define W83L786NG_REG_CHIP_ID		0x4E
61 
62 #define W83L786NG_REG_DIODE		0x53
63 #define W83L786NG_REG_FAN_DIV		0x54
64 #define W83L786NG_REG_FAN_CFG		0x80
65 
66 #define W83L786NG_REG_TOLERANCE		0x8D
67 
68 static const u8 W83L786NG_REG_TEMP[2][3] = {
69 	{ 0x25,		/* TEMP 0 in DataSheet */
70 	  0x35,		/* TEMP 0 Over in DataSheet */
71 	  0x36 },	/* TEMP 0 Hyst in DataSheet */
72 	{ 0x26,		/* TEMP 1 in DataSheet */
73 	  0x37,		/* TEMP 1 Over in DataSheet */
74 	  0x38 }	/* TEMP 1 Hyst in DataSheet */
75 };
76 
77 static const u8 W83L786NG_PWM_MODE_SHIFT[] = {6, 7};
78 static const u8 W83L786NG_PWM_ENABLE_SHIFT[] = {2, 4};
79 
80 /* FAN Duty Cycle, be used to control */
81 static const u8 W83L786NG_REG_PWM[] = {0x81, 0x87};
82 
83 
84 static inline u8
85 FAN_TO_REG(long rpm, int div)
86 {
87 	if (rpm == 0)
88 		return 255;
89 	rpm = clamp_val(rpm, 1, 1000000);
90 	return clamp_val((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
91 }
92 
93 #define FAN_FROM_REG(val, div)	((val) == 0   ? -1 : \
94 				((val) == 255 ? 0 : \
95 				1350000 / ((val) * (div))))
96 
97 /* for temp */
98 #define TEMP_TO_REG(val)	(clamp_val(((val) < 0 ? (val) + 0x100 * 1000 \
99 						      : (val)) / 1000, 0, 0xff))
100 #define TEMP_FROM_REG(val)	(((val) & 0x80 ? \
101 				  (val) - 0x100 : (val)) * 1000)
102 
103 /*
104  * The analog voltage inputs have 8mV LSB. Since the sysfs output is
105  * in mV as would be measured on the chip input pin, need to just
106  * multiply/divide by 8 to translate from/to register values.
107  */
108 #define IN_TO_REG(val)		(clamp_val((((val) + 4) / 8), 0, 255))
109 #define IN_FROM_REG(val)	((val) * 8)
110 
111 #define DIV_FROM_REG(val)	(1 << (val))
112 
113 static inline u8
114 DIV_TO_REG(long val)
115 {
116 	int i;
117 	val = clamp_val(val, 1, 128) >> 1;
118 	for (i = 0; i < 7; i++) {
119 		if (val == 0)
120 			break;
121 		val >>= 1;
122 	}
123 	return (u8)i;
124 }
125 
126 struct w83l786ng_data {
127 	struct i2c_client *client;
128 	struct mutex update_lock;
129 	char valid;			/* !=0 if following fields are valid */
130 	unsigned long last_updated;	/* In jiffies */
131 	unsigned long last_nonvolatile;	/* In jiffies, last time we update the
132 					 * nonvolatile registers */
133 
134 	u8 in[3];
135 	u8 in_max[3];
136 	u8 in_min[3];
137 	u8 fan[2];
138 	u8 fan_div[2];
139 	u8 fan_min[2];
140 	u8 temp_type[2];
141 	u8 temp[2][3];
142 	u8 pwm[2];
143 	u8 pwm_mode[2];	/* 0->DC variable voltage
144 			 * 1->PWM variable duty cycle */
145 
146 	u8 pwm_enable[2]; /* 1->manual
147 			   * 2->thermal cruise (also called SmartFan I) */
148 	u8 tolerance[2];
149 };
150 
151 static u8
152 w83l786ng_read_value(struct i2c_client *client, u8 reg)
153 {
154 	return i2c_smbus_read_byte_data(client, reg);
155 }
156 
157 static int
158 w83l786ng_write_value(struct i2c_client *client, u8 reg, u8 value)
159 {
160 	return i2c_smbus_write_byte_data(client, reg, value);
161 }
162 
163 static struct w83l786ng_data *w83l786ng_update_device(struct device *dev)
164 {
165 	struct w83l786ng_data *data = dev_get_drvdata(dev);
166 	struct i2c_client *client = data->client;
167 	int i, j;
168 	u8 reg_tmp, pwmcfg;
169 
170 	mutex_lock(&data->update_lock);
171 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
172 	    || !data->valid) {
173 		dev_dbg(&client->dev, "Updating w83l786ng data.\n");
174 
175 		/* Update the voltages measured value and limits */
176 		for (i = 0; i < 3; i++) {
177 			data->in[i] = w83l786ng_read_value(client,
178 			    W83L786NG_REG_IN(i));
179 			data->in_min[i] = w83l786ng_read_value(client,
180 			    W83L786NG_REG_IN_MIN(i));
181 			data->in_max[i] = w83l786ng_read_value(client,
182 			    W83L786NG_REG_IN_MAX(i));
183 		}
184 
185 		/* Update the fan counts and limits */
186 		for (i = 0; i < 2; i++) {
187 			data->fan[i] = w83l786ng_read_value(client,
188 			    W83L786NG_REG_FAN(i));
189 			data->fan_min[i] = w83l786ng_read_value(client,
190 			    W83L786NG_REG_FAN_MIN(i));
191 		}
192 
193 		/* Update the fan divisor */
194 		reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV);
195 		data->fan_div[0] = reg_tmp & 0x07;
196 		data->fan_div[1] = (reg_tmp >> 4) & 0x07;
197 
198 		pwmcfg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
199 		for (i = 0; i < 2; i++) {
200 			data->pwm_mode[i] =
201 			    ((pwmcfg >> W83L786NG_PWM_MODE_SHIFT[i]) & 1)
202 			    ? 0 : 1;
203 			data->pwm_enable[i] =
204 			    ((pwmcfg >> W83L786NG_PWM_ENABLE_SHIFT[i]) & 3) + 1;
205 			data->pwm[i] =
206 			    (w83l786ng_read_value(client, W83L786NG_REG_PWM[i])
207 			     & 0x0f) * 0x11;
208 		}
209 
210 
211 		/* Update the temperature sensors */
212 		for (i = 0; i < 2; i++) {
213 			for (j = 0; j < 3; j++) {
214 				data->temp[i][j] = w83l786ng_read_value(client,
215 				    W83L786NG_REG_TEMP[i][j]);
216 			}
217 		}
218 
219 		/* Update Smart Fan I/II tolerance */
220 		reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_TOLERANCE);
221 		data->tolerance[0] = reg_tmp & 0x0f;
222 		data->tolerance[1] = (reg_tmp >> 4) & 0x0f;
223 
224 		data->last_updated = jiffies;
225 		data->valid = 1;
226 
227 	}
228 
229 	mutex_unlock(&data->update_lock);
230 
231 	return data;
232 }
233 
234 /* following are the sysfs callback functions */
235 #define show_in_reg(reg) \
236 static ssize_t \
237 show_##reg(struct device *dev, struct device_attribute *attr, \
238 	   char *buf) \
239 { \
240 	int nr = to_sensor_dev_attr(attr)->index; \
241 	struct w83l786ng_data *data = w83l786ng_update_device(dev); \
242 	return sprintf(buf, "%d\n", IN_FROM_REG(data->reg[nr])); \
243 }
244 
245 show_in_reg(in)
246 show_in_reg(in_min)
247 show_in_reg(in_max)
248 
249 #define store_in_reg(REG, reg) \
250 static ssize_t \
251 store_in_##reg(struct device *dev, struct device_attribute *attr, \
252 	       const char *buf, size_t count) \
253 { \
254 	int nr = to_sensor_dev_attr(attr)->index; \
255 	struct w83l786ng_data *data = dev_get_drvdata(dev); \
256 	struct i2c_client *client = data->client; \
257 	unsigned long val; \
258 	int err = kstrtoul(buf, 10, &val); \
259 	if (err) \
260 		return err; \
261 	mutex_lock(&data->update_lock); \
262 	data->in_##reg[nr] = IN_TO_REG(val); \
263 	w83l786ng_write_value(client, W83L786NG_REG_IN_##REG(nr), \
264 			      data->in_##reg[nr]); \
265 	mutex_unlock(&data->update_lock); \
266 	return count; \
267 }
268 
269 store_in_reg(MIN, min)
270 store_in_reg(MAX, max)
271 
272 static struct sensor_device_attribute sda_in_input[] = {
273 	SENSOR_ATTR(in0_input, S_IRUGO, show_in, NULL, 0),
274 	SENSOR_ATTR(in1_input, S_IRUGO, show_in, NULL, 1),
275 	SENSOR_ATTR(in2_input, S_IRUGO, show_in, NULL, 2),
276 };
277 
278 static struct sensor_device_attribute sda_in_min[] = {
279 	SENSOR_ATTR(in0_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 0),
280 	SENSOR_ATTR(in1_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 1),
281 	SENSOR_ATTR(in2_min, S_IWUSR | S_IRUGO, show_in_min, store_in_min, 2),
282 };
283 
284 static struct sensor_device_attribute sda_in_max[] = {
285 	SENSOR_ATTR(in0_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 0),
286 	SENSOR_ATTR(in1_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 1),
287 	SENSOR_ATTR(in2_max, S_IWUSR | S_IRUGO, show_in_max, store_in_max, 2),
288 };
289 
290 #define show_fan_reg(reg) \
291 static ssize_t show_##reg(struct device *dev, struct device_attribute *attr, \
292 			  char *buf) \
293 { \
294 	int nr = to_sensor_dev_attr(attr)->index; \
295 	struct w83l786ng_data *data = w83l786ng_update_device(dev); \
296 	return sprintf(buf, "%d\n", \
297 		FAN_FROM_REG(data->reg[nr], DIV_FROM_REG(data->fan_div[nr]))); \
298 }
299 
300 show_fan_reg(fan);
301 show_fan_reg(fan_min);
302 
303 static ssize_t
304 store_fan_min(struct device *dev, struct device_attribute *attr,
305 	      const char *buf, size_t count)
306 {
307 	int nr = to_sensor_dev_attr(attr)->index;
308 	struct w83l786ng_data *data = dev_get_drvdata(dev);
309 	struct i2c_client *client = data->client;
310 	unsigned long val;
311 	int err;
312 
313 	err = kstrtoul(buf, 10, &val);
314 	if (err)
315 		return err;
316 
317 	mutex_lock(&data->update_lock);
318 	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
319 	w83l786ng_write_value(client, W83L786NG_REG_FAN_MIN(nr),
320 			      data->fan_min[nr]);
321 	mutex_unlock(&data->update_lock);
322 
323 	return count;
324 }
325 
326 static ssize_t
327 show_fan_div(struct device *dev, struct device_attribute *attr,
328 	     char *buf)
329 {
330 	int nr = to_sensor_dev_attr(attr)->index;
331 	struct w83l786ng_data *data = w83l786ng_update_device(dev);
332 	return sprintf(buf, "%u\n", DIV_FROM_REG(data->fan_div[nr]));
333 }
334 
335 /*
336  * Note: we save and restore the fan minimum here, because its value is
337  * determined in part by the fan divisor.  This follows the principle of
338  * least surprise; the user doesn't expect the fan minimum to change just
339  * because the divisor changed.
340  */
341 static ssize_t
342 store_fan_div(struct device *dev, struct device_attribute *attr,
343 	      const char *buf, size_t count)
344 {
345 	int nr = to_sensor_dev_attr(attr)->index;
346 	struct w83l786ng_data *data = dev_get_drvdata(dev);
347 	struct i2c_client *client = data->client;
348 
349 	unsigned long min;
350 	u8 tmp_fan_div;
351 	u8 fan_div_reg;
352 	u8 keep_mask = 0;
353 	u8 new_shift = 0;
354 
355 	unsigned long val;
356 	int err;
357 
358 	err = kstrtoul(buf, 10, &val);
359 	if (err)
360 		return err;
361 
362 	/* Save fan_min */
363 	mutex_lock(&data->update_lock);
364 	min = FAN_FROM_REG(data->fan_min[nr], DIV_FROM_REG(data->fan_div[nr]));
365 
366 	data->fan_div[nr] = DIV_TO_REG(val);
367 
368 	switch (nr) {
369 	case 0:
370 		keep_mask = 0xf8;
371 		new_shift = 0;
372 		break;
373 	case 1:
374 		keep_mask = 0x8f;
375 		new_shift = 4;
376 		break;
377 	}
378 
379 	fan_div_reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV)
380 					   & keep_mask;
381 
382 	tmp_fan_div = (data->fan_div[nr] << new_shift) & ~keep_mask;
383 
384 	w83l786ng_write_value(client, W83L786NG_REG_FAN_DIV,
385 			      fan_div_reg | tmp_fan_div);
386 
387 	/* Restore fan_min */
388 	data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
389 	w83l786ng_write_value(client, W83L786NG_REG_FAN_MIN(nr),
390 			      data->fan_min[nr]);
391 	mutex_unlock(&data->update_lock);
392 
393 	return count;
394 }
395 
396 static struct sensor_device_attribute sda_fan_input[] = {
397 	SENSOR_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0),
398 	SENSOR_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 1),
399 };
400 
401 static struct sensor_device_attribute sda_fan_min[] = {
402 	SENSOR_ATTR(fan1_min, S_IWUSR | S_IRUGO, show_fan_min,
403 		    store_fan_min, 0),
404 	SENSOR_ATTR(fan2_min, S_IWUSR | S_IRUGO, show_fan_min,
405 		    store_fan_min, 1),
406 };
407 
408 static struct sensor_device_attribute sda_fan_div[] = {
409 	SENSOR_ATTR(fan1_div, S_IWUSR | S_IRUGO, show_fan_div,
410 		    store_fan_div, 0),
411 	SENSOR_ATTR(fan2_div, S_IWUSR | S_IRUGO, show_fan_div,
412 		    store_fan_div, 1),
413 };
414 
415 
416 /* read/write the temperature, includes measured value and limits */
417 
418 static ssize_t
419 show_temp(struct device *dev, struct device_attribute *attr, char *buf)
420 {
421 	struct sensor_device_attribute_2 *sensor_attr =
422 	    to_sensor_dev_attr_2(attr);
423 	int nr = sensor_attr->nr;
424 	int index = sensor_attr->index;
425 	struct w83l786ng_data *data = w83l786ng_update_device(dev);
426 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr][index]));
427 }
428 
429 static ssize_t
430 store_temp(struct device *dev, struct device_attribute *attr,
431 	   const char *buf, size_t count)
432 {
433 	struct sensor_device_attribute_2 *sensor_attr =
434 	    to_sensor_dev_attr_2(attr);
435 	int nr = sensor_attr->nr;
436 	int index = sensor_attr->index;
437 	struct w83l786ng_data *data = dev_get_drvdata(dev);
438 	struct i2c_client *client = data->client;
439 	long val;
440 	int err;
441 
442 	err = kstrtol(buf, 10, &val);
443 	if (err)
444 		return err;
445 
446 	mutex_lock(&data->update_lock);
447 	data->temp[nr][index] = TEMP_TO_REG(val);
448 	w83l786ng_write_value(client, W83L786NG_REG_TEMP[nr][index],
449 			      data->temp[nr][index]);
450 	mutex_unlock(&data->update_lock);
451 
452 	return count;
453 }
454 
455 static struct sensor_device_attribute_2 sda_temp_input[] = {
456 	SENSOR_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0, 0),
457 	SENSOR_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 1, 0),
458 };
459 
460 static struct sensor_device_attribute_2 sda_temp_max[] = {
461 	SENSOR_ATTR_2(temp1_max, S_IRUGO | S_IWUSR,
462 		      show_temp, store_temp, 0, 1),
463 	SENSOR_ATTR_2(temp2_max, S_IRUGO | S_IWUSR,
464 		      show_temp, store_temp, 1, 1),
465 };
466 
467 static struct sensor_device_attribute_2 sda_temp_max_hyst[] = {
468 	SENSOR_ATTR_2(temp1_max_hyst, S_IRUGO | S_IWUSR,
469 		      show_temp, store_temp, 0, 2),
470 	SENSOR_ATTR_2(temp2_max_hyst, S_IRUGO | S_IWUSR,
471 		      show_temp, store_temp, 1, 2),
472 };
473 
474 #define show_pwm_reg(reg) \
475 static ssize_t show_##reg(struct device *dev, struct device_attribute *attr, \
476 			  char *buf) \
477 { \
478 	struct w83l786ng_data *data = w83l786ng_update_device(dev); \
479 	int nr = to_sensor_dev_attr(attr)->index; \
480 	return sprintf(buf, "%d\n", data->reg[nr]); \
481 }
482 
483 show_pwm_reg(pwm_mode)
484 show_pwm_reg(pwm_enable)
485 show_pwm_reg(pwm)
486 
487 static ssize_t
488 store_pwm_mode(struct device *dev, struct device_attribute *attr,
489 	       const char *buf, size_t count)
490 {
491 	int nr = to_sensor_dev_attr(attr)->index;
492 	struct w83l786ng_data *data = dev_get_drvdata(dev);
493 	struct i2c_client *client = data->client;
494 	u8 reg;
495 	unsigned long val;
496 	int err;
497 
498 	err = kstrtoul(buf, 10, &val);
499 	if (err)
500 		return err;
501 
502 	if (val > 1)
503 		return -EINVAL;
504 	mutex_lock(&data->update_lock);
505 	data->pwm_mode[nr] = val;
506 	reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
507 	reg &= ~(1 << W83L786NG_PWM_MODE_SHIFT[nr]);
508 	if (!val)
509 		reg |= 1 << W83L786NG_PWM_MODE_SHIFT[nr];
510 	w83l786ng_write_value(client, W83L786NG_REG_FAN_CFG, reg);
511 	mutex_unlock(&data->update_lock);
512 	return count;
513 }
514 
515 static ssize_t
516 store_pwm(struct device *dev, struct device_attribute *attr,
517 	  const char *buf, size_t count)
518 {
519 	int nr = to_sensor_dev_attr(attr)->index;
520 	struct w83l786ng_data *data = dev_get_drvdata(dev);
521 	struct i2c_client *client = data->client;
522 	unsigned long val;
523 	int err;
524 
525 	err = kstrtoul(buf, 10, &val);
526 	if (err)
527 		return err;
528 	val = clamp_val(val, 0, 255);
529 	val = DIV_ROUND_CLOSEST(val, 0x11);
530 
531 	mutex_lock(&data->update_lock);
532 	data->pwm[nr] = val * 0x11;
533 	val |= w83l786ng_read_value(client, W83L786NG_REG_PWM[nr]) & 0xf0;
534 	w83l786ng_write_value(client, W83L786NG_REG_PWM[nr], val);
535 	mutex_unlock(&data->update_lock);
536 	return count;
537 }
538 
539 static ssize_t
540 store_pwm_enable(struct device *dev, struct device_attribute *attr,
541 		 const char *buf, size_t count)
542 {
543 	int nr = to_sensor_dev_attr(attr)->index;
544 	struct w83l786ng_data *data = dev_get_drvdata(dev);
545 	struct i2c_client *client = data->client;
546 	u8 reg;
547 	unsigned long val;
548 	int err;
549 
550 	err = kstrtoul(buf, 10, &val);
551 	if (err)
552 		return err;
553 
554 	if (!val || val > 2)  /* only modes 1 and 2 are supported */
555 		return -EINVAL;
556 
557 	mutex_lock(&data->update_lock);
558 	reg = w83l786ng_read_value(client, W83L786NG_REG_FAN_CFG);
559 	data->pwm_enable[nr] = val;
560 	reg &= ~(0x03 << W83L786NG_PWM_ENABLE_SHIFT[nr]);
561 	reg |= (val - 1) << W83L786NG_PWM_ENABLE_SHIFT[nr];
562 	w83l786ng_write_value(client, W83L786NG_REG_FAN_CFG, reg);
563 	mutex_unlock(&data->update_lock);
564 	return count;
565 }
566 
567 static struct sensor_device_attribute sda_pwm[] = {
568 	SENSOR_ATTR(pwm1, S_IWUSR | S_IRUGO, show_pwm, store_pwm, 0),
569 	SENSOR_ATTR(pwm2, S_IWUSR | S_IRUGO, show_pwm, store_pwm, 1),
570 };
571 
572 static struct sensor_device_attribute sda_pwm_mode[] = {
573 	SENSOR_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, show_pwm_mode,
574 		    store_pwm_mode, 0),
575 	SENSOR_ATTR(pwm2_mode, S_IWUSR | S_IRUGO, show_pwm_mode,
576 		    store_pwm_mode, 1),
577 };
578 
579 static struct sensor_device_attribute sda_pwm_enable[] = {
580 	SENSOR_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, show_pwm_enable,
581 		    store_pwm_enable, 0),
582 	SENSOR_ATTR(pwm2_enable, S_IWUSR | S_IRUGO, show_pwm_enable,
583 		    store_pwm_enable, 1),
584 };
585 
586 /* For Smart Fan I/Thermal Cruise and Smart Fan II */
587 static ssize_t
588 show_tolerance(struct device *dev, struct device_attribute *attr, char *buf)
589 {
590 	int nr = to_sensor_dev_attr(attr)->index;
591 	struct w83l786ng_data *data = w83l786ng_update_device(dev);
592 	return sprintf(buf, "%ld\n", (long)data->tolerance[nr]);
593 }
594 
595 static ssize_t
596 store_tolerance(struct device *dev, struct device_attribute *attr,
597 		const char *buf, size_t count)
598 {
599 	int nr = to_sensor_dev_attr(attr)->index;
600 	struct w83l786ng_data *data = dev_get_drvdata(dev);
601 	struct i2c_client *client = data->client;
602 	u8 tol_tmp, tol_mask;
603 	unsigned long val;
604 	int err;
605 
606 	err = kstrtoul(buf, 10, &val);
607 	if (err)
608 		return err;
609 
610 	mutex_lock(&data->update_lock);
611 	tol_mask = w83l786ng_read_value(client,
612 	    W83L786NG_REG_TOLERANCE) & ((nr == 1) ? 0x0f : 0xf0);
613 	tol_tmp = clamp_val(val, 0, 15);
614 	tol_tmp &= 0x0f;
615 	data->tolerance[nr] = tol_tmp;
616 	if (nr == 1)
617 		tol_tmp <<= 4;
618 
619 	w83l786ng_write_value(client, W83L786NG_REG_TOLERANCE,
620 			      tol_mask | tol_tmp);
621 	mutex_unlock(&data->update_lock);
622 	return count;
623 }
624 
625 static struct sensor_device_attribute sda_tolerance[] = {
626 	SENSOR_ATTR(pwm1_tolerance, S_IWUSR | S_IRUGO,
627 		    show_tolerance, store_tolerance, 0),
628 	SENSOR_ATTR(pwm2_tolerance, S_IWUSR | S_IRUGO,
629 		    show_tolerance, store_tolerance, 1),
630 };
631 
632 
633 #define IN_UNIT_ATTRS(X)	\
634 	&sda_in_input[X].dev_attr.attr,		\
635 	&sda_in_min[X].dev_attr.attr,		\
636 	&sda_in_max[X].dev_attr.attr
637 
638 #define FAN_UNIT_ATTRS(X)	\
639 	&sda_fan_input[X].dev_attr.attr,	\
640 	&sda_fan_min[X].dev_attr.attr,		\
641 	&sda_fan_div[X].dev_attr.attr
642 
643 #define TEMP_UNIT_ATTRS(X)	\
644 	&sda_temp_input[X].dev_attr.attr,	\
645 	&sda_temp_max[X].dev_attr.attr,		\
646 	&sda_temp_max_hyst[X].dev_attr.attr
647 
648 #define PWM_UNIT_ATTRS(X)	\
649 	&sda_pwm[X].dev_attr.attr,		\
650 	&sda_pwm_mode[X].dev_attr.attr,		\
651 	&sda_pwm_enable[X].dev_attr.attr
652 
653 #define TOLERANCE_UNIT_ATTRS(X)	\
654 	&sda_tolerance[X].dev_attr.attr
655 
656 static struct attribute *w83l786ng_attrs[] = {
657 	IN_UNIT_ATTRS(0),
658 	IN_UNIT_ATTRS(1),
659 	IN_UNIT_ATTRS(2),
660 	FAN_UNIT_ATTRS(0),
661 	FAN_UNIT_ATTRS(1),
662 	TEMP_UNIT_ATTRS(0),
663 	TEMP_UNIT_ATTRS(1),
664 	PWM_UNIT_ATTRS(0),
665 	PWM_UNIT_ATTRS(1),
666 	TOLERANCE_UNIT_ATTRS(0),
667 	TOLERANCE_UNIT_ATTRS(1),
668 	NULL
669 };
670 
671 ATTRIBUTE_GROUPS(w83l786ng);
672 
673 static int
674 w83l786ng_detect(struct i2c_client *client, struct i2c_board_info *info)
675 {
676 	struct i2c_adapter *adapter = client->adapter;
677 	u16 man_id;
678 	u8 chip_id;
679 
680 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
681 		return -ENODEV;
682 
683 	/* Detection */
684 	if ((w83l786ng_read_value(client, W83L786NG_REG_CONFIG) & 0x80)) {
685 		dev_dbg(&adapter->dev, "W83L786NG detection failed at 0x%02x\n",
686 			client->addr);
687 		return -ENODEV;
688 	}
689 
690 	/* Identification */
691 	man_id = (w83l786ng_read_value(client, W83L786NG_REG_MAN_ID1) << 8) +
692 		 w83l786ng_read_value(client, W83L786NG_REG_MAN_ID2);
693 	chip_id = w83l786ng_read_value(client, W83L786NG_REG_CHIP_ID);
694 
695 	if (man_id != 0x5CA3 ||		/* Winbond */
696 	    chip_id != 0x80) {		/* W83L786NG */
697 		dev_dbg(&adapter->dev,
698 			"Unsupported chip (man_id=0x%04X, chip_id=0x%02X)\n",
699 			man_id, chip_id);
700 		return -ENODEV;
701 	}
702 
703 	strlcpy(info->type, "w83l786ng", I2C_NAME_SIZE);
704 
705 	return 0;
706 }
707 
708 static void w83l786ng_init_client(struct i2c_client *client)
709 {
710 	u8 tmp;
711 
712 	if (reset)
713 		w83l786ng_write_value(client, W83L786NG_REG_CONFIG, 0x80);
714 
715 	/* Start monitoring */
716 	tmp = w83l786ng_read_value(client, W83L786NG_REG_CONFIG);
717 	if (!(tmp & 0x01))
718 		w83l786ng_write_value(client, W83L786NG_REG_CONFIG, tmp | 0x01);
719 }
720 
721 static int
722 w83l786ng_probe(struct i2c_client *client, const struct i2c_device_id *id)
723 {
724 	struct device *dev = &client->dev;
725 	struct w83l786ng_data *data;
726 	struct device *hwmon_dev;
727 	int i;
728 	u8 reg_tmp;
729 
730 	data = devm_kzalloc(dev, sizeof(struct w83l786ng_data), GFP_KERNEL);
731 	if (!data)
732 		return -ENOMEM;
733 
734 	data->client = client;
735 	mutex_init(&data->update_lock);
736 
737 	/* Initialize the chip */
738 	w83l786ng_init_client(client);
739 
740 	/* A few vars need to be filled upon startup */
741 	for (i = 0; i < 2; i++) {
742 		data->fan_min[i] = w83l786ng_read_value(client,
743 		    W83L786NG_REG_FAN_MIN(i));
744 	}
745 
746 	/* Update the fan divisor */
747 	reg_tmp = w83l786ng_read_value(client, W83L786NG_REG_FAN_DIV);
748 	data->fan_div[0] = reg_tmp & 0x07;
749 	data->fan_div[1] = (reg_tmp >> 4) & 0x07;
750 
751 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
752 							   data,
753 							   w83l786ng_groups);
754 	return PTR_ERR_OR_ZERO(hwmon_dev);
755 }
756 
757 static const struct i2c_device_id w83l786ng_id[] = {
758 	{ "w83l786ng", 0 },
759 	{ }
760 };
761 MODULE_DEVICE_TABLE(i2c, w83l786ng_id);
762 
763 static struct i2c_driver w83l786ng_driver = {
764 	.class		= I2C_CLASS_HWMON,
765 	.driver = {
766 		   .name = "w83l786ng",
767 	},
768 	.probe		= w83l786ng_probe,
769 	.id_table	= w83l786ng_id,
770 	.detect		= w83l786ng_detect,
771 	.address_list	= normal_i2c,
772 };
773 
774 module_i2c_driver(w83l786ng_driver);
775 
776 MODULE_AUTHOR("Kevin Lo");
777 MODULE_DESCRIPTION("w83l786ng driver");
778 MODULE_LICENSE("GPL");
779