xref: /linux/drivers/hwmon/nct7802.c (revision 0b8061c340b643e01da431dd60c75a41bb1d31ec)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * nct7802 - Driver for Nuvoton NCT7802Y
4  *
5  * Copyright (C) 2014  Guenter Roeck <linux@roeck-us.net>
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/err.h>
11 #include <linux/i2c.h>
12 #include <linux/init.h>
13 #include <linux/hwmon.h>
14 #include <linux/hwmon-sysfs.h>
15 #include <linux/jiffies.h>
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/regmap.h>
19 #include <linux/slab.h>
20 
21 #define DRVNAME "nct7802"
22 
23 static const u8 REG_VOLTAGE[5] = { 0x09, 0x0a, 0x0c, 0x0d, 0x0e };
24 
25 static const u8 REG_VOLTAGE_LIMIT_LSB[2][5] = {
26 	{ 0x46, 0x00, 0x40, 0x42, 0x44 },
27 	{ 0x45, 0x00, 0x3f, 0x41, 0x43 },
28 };
29 
30 static const u8 REG_VOLTAGE_LIMIT_MSB[5] = { 0x48, 0x00, 0x47, 0x47, 0x48 };
31 
32 static const u8 REG_VOLTAGE_LIMIT_MSB_SHIFT[2][5] = {
33 	{ 0, 0, 4, 0, 4 },
34 	{ 2, 0, 6, 2, 6 },
35 };
36 
37 #define REG_BANK		0x00
38 #define REG_TEMP_LSB		0x05
39 #define REG_TEMP_PECI_LSB	0x08
40 #define REG_VOLTAGE_LOW		0x0f
41 #define REG_FANCOUNT_LOW	0x13
42 #define REG_START		0x21
43 #define REG_MODE		0x22 /* 7.2.32 Mode Selection Register */
44 #define REG_PECI_ENABLE		0x23
45 #define REG_FAN_ENABLE		0x24
46 #define REG_VMON_ENABLE		0x25
47 #define REG_PWM(x)		(0x60 + (x))
48 #define REG_SMARTFAN_EN(x)      (0x64 + (x) / 2)
49 #define SMARTFAN_EN_SHIFT(x)    ((x) % 2 * 4)
50 #define REG_VENDOR_ID		0xfd
51 #define REG_CHIP_ID		0xfe
52 #define REG_VERSION_ID		0xff
53 
54 /*
55  * Data structures and manipulation thereof
56  */
57 
58 struct nct7802_data {
59 	struct regmap *regmap;
60 	struct mutex access_lock; /* for multi-byte read and write operations */
61 	u8 in_status;
62 	struct mutex in_alarm_lock;
63 };
64 
65 static ssize_t temp_type_show(struct device *dev,
66 			      struct device_attribute *attr, char *buf)
67 {
68 	struct nct7802_data *data = dev_get_drvdata(dev);
69 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
70 	unsigned int mode;
71 	int ret;
72 
73 	ret = regmap_read(data->regmap, REG_MODE, &mode);
74 	if (ret < 0)
75 		return ret;
76 
77 	return sprintf(buf, "%u\n", (mode >> (2 * sattr->index) & 3) + 2);
78 }
79 
80 static ssize_t temp_type_store(struct device *dev,
81 			       struct device_attribute *attr, const char *buf,
82 			       size_t count)
83 {
84 	struct nct7802_data *data = dev_get_drvdata(dev);
85 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
86 	unsigned int type;
87 	int err;
88 
89 	err = kstrtouint(buf, 0, &type);
90 	if (err < 0)
91 		return err;
92 	if (sattr->index == 2 && type != 4) /* RD3 */
93 		return -EINVAL;
94 	if (type < 3 || type > 4)
95 		return -EINVAL;
96 	err = regmap_update_bits(data->regmap, REG_MODE,
97 			3 << 2 * sattr->index, (type - 2) << 2 * sattr->index);
98 	return err ? : count;
99 }
100 
101 static ssize_t pwm_mode_show(struct device *dev,
102 			     struct device_attribute *attr, char *buf)
103 {
104 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
105 	struct nct7802_data *data = dev_get_drvdata(dev);
106 	unsigned int regval;
107 	int ret;
108 
109 	if (sattr->index > 1)
110 		return sprintf(buf, "1\n");
111 
112 	ret = regmap_read(data->regmap, 0x5E, &regval);
113 	if (ret < 0)
114 		return ret;
115 
116 	return sprintf(buf, "%u\n", !(regval & (1 << sattr->index)));
117 }
118 
119 static ssize_t pwm_show(struct device *dev, struct device_attribute *devattr,
120 			char *buf)
121 {
122 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
123 	struct nct7802_data *data = dev_get_drvdata(dev);
124 	unsigned int val;
125 	int ret;
126 
127 	if (!attr->index)
128 		return sprintf(buf, "255\n");
129 
130 	ret = regmap_read(data->regmap, attr->index, &val);
131 	if (ret < 0)
132 		return ret;
133 
134 	return sprintf(buf, "%d\n", val);
135 }
136 
137 static ssize_t pwm_store(struct device *dev, struct device_attribute *devattr,
138 			 const char *buf, size_t count)
139 {
140 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
141 	struct nct7802_data *data = dev_get_drvdata(dev);
142 	int err;
143 	u8 val;
144 
145 	err = kstrtou8(buf, 0, &val);
146 	if (err < 0)
147 		return err;
148 
149 	err = regmap_write(data->regmap, attr->index, val);
150 	return err ? : count;
151 }
152 
153 static ssize_t pwm_enable_show(struct device *dev,
154 			       struct device_attribute *attr, char *buf)
155 {
156 	struct nct7802_data *data = dev_get_drvdata(dev);
157 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
158 	unsigned int reg, enabled;
159 	int ret;
160 
161 	ret = regmap_read(data->regmap, REG_SMARTFAN_EN(sattr->index), &reg);
162 	if (ret < 0)
163 		return ret;
164 	enabled = reg >> SMARTFAN_EN_SHIFT(sattr->index) & 1;
165 	return sprintf(buf, "%u\n", enabled + 1);
166 }
167 
168 static ssize_t pwm_enable_store(struct device *dev,
169 				struct device_attribute *attr,
170 				const char *buf, size_t count)
171 {
172 	struct nct7802_data *data = dev_get_drvdata(dev);
173 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
174 	u8 val;
175 	int ret;
176 
177 	ret = kstrtou8(buf, 0, &val);
178 	if (ret < 0)
179 		return ret;
180 	if (val < 1 || val > 2)
181 		return -EINVAL;
182 	ret = regmap_update_bits(data->regmap, REG_SMARTFAN_EN(sattr->index),
183 				 1 << SMARTFAN_EN_SHIFT(sattr->index),
184 				 (val - 1) << SMARTFAN_EN_SHIFT(sattr->index));
185 	return ret ? : count;
186 }
187 
188 static int nct7802_read_temp(struct nct7802_data *data,
189 			     u8 reg_temp, u8 reg_temp_low, int *temp)
190 {
191 	unsigned int t1, t2 = 0;
192 	int err;
193 
194 	*temp = 0;
195 
196 	mutex_lock(&data->access_lock);
197 	err = regmap_read(data->regmap, reg_temp, &t1);
198 	if (err < 0)
199 		goto abort;
200 	t1 <<= 8;
201 	if (reg_temp_low) {	/* 11 bit data */
202 		err = regmap_read(data->regmap, reg_temp_low, &t2);
203 		if (err < 0)
204 			goto abort;
205 	}
206 	t1 |= t2 & 0xe0;
207 	*temp = (s16)t1 / 32 * 125;
208 abort:
209 	mutex_unlock(&data->access_lock);
210 	return err;
211 }
212 
213 static int nct7802_read_fan(struct nct7802_data *data, u8 reg_fan)
214 {
215 	unsigned int f1, f2;
216 	int ret;
217 
218 	mutex_lock(&data->access_lock);
219 	ret = regmap_read(data->regmap, reg_fan, &f1);
220 	if (ret < 0)
221 		goto abort;
222 	ret = regmap_read(data->regmap, REG_FANCOUNT_LOW, &f2);
223 	if (ret < 0)
224 		goto abort;
225 	ret = (f1 << 5) | (f2 >> 3);
226 	/* convert fan count to rpm */
227 	if (ret == 0x1fff)	/* maximum value, assume fan is stopped */
228 		ret = 0;
229 	else if (ret)
230 		ret = DIV_ROUND_CLOSEST(1350000U, ret);
231 abort:
232 	mutex_unlock(&data->access_lock);
233 	return ret;
234 }
235 
236 static int nct7802_read_fan_min(struct nct7802_data *data, u8 reg_fan_low,
237 				u8 reg_fan_high)
238 {
239 	unsigned int f1, f2;
240 	int ret;
241 
242 	mutex_lock(&data->access_lock);
243 	ret = regmap_read(data->regmap, reg_fan_low, &f1);
244 	if (ret < 0)
245 		goto abort;
246 	ret = regmap_read(data->regmap, reg_fan_high, &f2);
247 	if (ret < 0)
248 		goto abort;
249 	ret = f1 | ((f2 & 0xf8) << 5);
250 	/* convert fan count to rpm */
251 	if (ret == 0x1fff)	/* maximum value, assume no limit */
252 		ret = 0;
253 	else if (ret)
254 		ret = DIV_ROUND_CLOSEST(1350000U, ret);
255 	else
256 		ret = 1350000U;
257 abort:
258 	mutex_unlock(&data->access_lock);
259 	return ret;
260 }
261 
262 static int nct7802_write_fan_min(struct nct7802_data *data, u8 reg_fan_low,
263 				 u8 reg_fan_high, unsigned long limit)
264 {
265 	int err;
266 
267 	if (limit)
268 		limit = DIV_ROUND_CLOSEST(1350000U, limit);
269 	else
270 		limit = 0x1fff;
271 	limit = clamp_val(limit, 0, 0x1fff);
272 
273 	mutex_lock(&data->access_lock);
274 	err = regmap_write(data->regmap, reg_fan_low, limit & 0xff);
275 	if (err < 0)
276 		goto abort;
277 
278 	err = regmap_write(data->regmap, reg_fan_high, (limit & 0x1f00) >> 5);
279 abort:
280 	mutex_unlock(&data->access_lock);
281 	return err;
282 }
283 
284 static u8 nct7802_vmul[] = { 4, 2, 2, 2, 2 };
285 
286 static int nct7802_read_voltage(struct nct7802_data *data, int nr, int index)
287 {
288 	unsigned int v1, v2;
289 	int ret;
290 
291 	mutex_lock(&data->access_lock);
292 	if (index == 0) {	/* voltage */
293 		ret = regmap_read(data->regmap, REG_VOLTAGE[nr], &v1);
294 		if (ret < 0)
295 			goto abort;
296 		ret = regmap_read(data->regmap, REG_VOLTAGE_LOW, &v2);
297 		if (ret < 0)
298 			goto abort;
299 		ret = ((v1 << 2) | (v2 >> 6)) * nct7802_vmul[nr];
300 	}  else {	/* limit */
301 		int shift = 8 - REG_VOLTAGE_LIMIT_MSB_SHIFT[index - 1][nr];
302 
303 		ret = regmap_read(data->regmap,
304 				  REG_VOLTAGE_LIMIT_LSB[index - 1][nr], &v1);
305 		if (ret < 0)
306 			goto abort;
307 		ret = regmap_read(data->regmap, REG_VOLTAGE_LIMIT_MSB[nr],
308 				  &v2);
309 		if (ret < 0)
310 			goto abort;
311 		ret = (v1 | ((v2 << shift) & 0x300)) * nct7802_vmul[nr];
312 	}
313 abort:
314 	mutex_unlock(&data->access_lock);
315 	return ret;
316 }
317 
318 static int nct7802_write_voltage(struct nct7802_data *data, int nr, int index,
319 				 unsigned long voltage)
320 {
321 	int shift = 8 - REG_VOLTAGE_LIMIT_MSB_SHIFT[index - 1][nr];
322 	int err;
323 
324 	voltage = clamp_val(voltage, 0, 0x3ff * nct7802_vmul[nr]);
325 	voltage = DIV_ROUND_CLOSEST(voltage, nct7802_vmul[nr]);
326 
327 	mutex_lock(&data->access_lock);
328 	err = regmap_write(data->regmap,
329 			   REG_VOLTAGE_LIMIT_LSB[index - 1][nr],
330 			   voltage & 0xff);
331 	if (err < 0)
332 		goto abort;
333 
334 	err = regmap_update_bits(data->regmap, REG_VOLTAGE_LIMIT_MSB[nr],
335 				 0x0300 >> shift, (voltage & 0x0300) >> shift);
336 abort:
337 	mutex_unlock(&data->access_lock);
338 	return err;
339 }
340 
341 static ssize_t in_show(struct device *dev, struct device_attribute *attr,
342 		       char *buf)
343 {
344 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
345 	struct nct7802_data *data = dev_get_drvdata(dev);
346 	int voltage;
347 
348 	voltage = nct7802_read_voltage(data, sattr->nr, sattr->index);
349 	if (voltage < 0)
350 		return voltage;
351 
352 	return sprintf(buf, "%d\n", voltage);
353 }
354 
355 static ssize_t in_store(struct device *dev, struct device_attribute *attr,
356 			const char *buf, size_t count)
357 {
358 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
359 	struct nct7802_data *data = dev_get_drvdata(dev);
360 	int index = sattr->index;
361 	int nr = sattr->nr;
362 	unsigned long val;
363 	int err;
364 
365 	err = kstrtoul(buf, 10, &val);
366 	if (err < 0)
367 		return err;
368 
369 	err = nct7802_write_voltage(data, nr, index, val);
370 	return err ? : count;
371 }
372 
373 static ssize_t in_alarm_show(struct device *dev, struct device_attribute *attr,
374 			     char *buf)
375 {
376 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
377 	struct nct7802_data *data = dev_get_drvdata(dev);
378 	int volt, min, max, ret;
379 	unsigned int val;
380 
381 	mutex_lock(&data->in_alarm_lock);
382 
383 	/*
384 	 * The SMI Voltage status register is the only register giving a status
385 	 * for voltages. A bit is set for each input crossing a threshold, in
386 	 * both direction, but the "inside" or "outside" limits info is not
387 	 * available. Also this register is cleared on read.
388 	 * Note: this is not explicitly spelled out in the datasheet, but
389 	 * from experiment.
390 	 * To deal with this we use a status cache with one validity bit and
391 	 * one status bit for each input. Validity is cleared at startup and
392 	 * each time the register reports a change, and the status is processed
393 	 * by software based on current input value and limits.
394 	 */
395 	ret = regmap_read(data->regmap, 0x1e, &val); /* SMI Voltage status */
396 	if (ret < 0)
397 		goto abort;
398 
399 	/* invalidate cached status for all inputs crossing a threshold */
400 	data->in_status &= ~((val & 0x0f) << 4);
401 
402 	/* if cached status for requested input is invalid, update it */
403 	if (!(data->in_status & (0x10 << sattr->index))) {
404 		ret = nct7802_read_voltage(data, sattr->nr, 0);
405 		if (ret < 0)
406 			goto abort;
407 		volt = ret;
408 
409 		ret = nct7802_read_voltage(data, sattr->nr, 1);
410 		if (ret < 0)
411 			goto abort;
412 		min = ret;
413 
414 		ret = nct7802_read_voltage(data, sattr->nr, 2);
415 		if (ret < 0)
416 			goto abort;
417 		max = ret;
418 
419 		if (volt < min || volt > max)
420 			data->in_status |= (1 << sattr->index);
421 		else
422 			data->in_status &= ~(1 << sattr->index);
423 
424 		data->in_status |= 0x10 << sattr->index;
425 	}
426 
427 	ret = sprintf(buf, "%u\n", !!(data->in_status & (1 << sattr->index)));
428 abort:
429 	mutex_unlock(&data->in_alarm_lock);
430 	return ret;
431 }
432 
433 static ssize_t temp_show(struct device *dev, struct device_attribute *attr,
434 			 char *buf)
435 {
436 	struct nct7802_data *data = dev_get_drvdata(dev);
437 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
438 	int err, temp;
439 
440 	err = nct7802_read_temp(data, sattr->nr, sattr->index, &temp);
441 	if (err < 0)
442 		return err;
443 
444 	return sprintf(buf, "%d\n", temp);
445 }
446 
447 static ssize_t temp_store(struct device *dev, struct device_attribute *attr,
448 			  const char *buf, size_t count)
449 {
450 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
451 	struct nct7802_data *data = dev_get_drvdata(dev);
452 	int nr = sattr->nr;
453 	long val;
454 	int err;
455 
456 	err = kstrtol(buf, 10, &val);
457 	if (err < 0)
458 		return err;
459 
460 	val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
461 
462 	err = regmap_write(data->regmap, nr, val & 0xff);
463 	return err ? : count;
464 }
465 
466 static ssize_t fan_show(struct device *dev, struct device_attribute *attr,
467 			char *buf)
468 {
469 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
470 	struct nct7802_data *data = dev_get_drvdata(dev);
471 	int speed;
472 
473 	speed = nct7802_read_fan(data, sattr->index);
474 	if (speed < 0)
475 		return speed;
476 
477 	return sprintf(buf, "%d\n", speed);
478 }
479 
480 static ssize_t fan_min_show(struct device *dev, struct device_attribute *attr,
481 			    char *buf)
482 {
483 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
484 	struct nct7802_data *data = dev_get_drvdata(dev);
485 	int speed;
486 
487 	speed = nct7802_read_fan_min(data, sattr->nr, sattr->index);
488 	if (speed < 0)
489 		return speed;
490 
491 	return sprintf(buf, "%d\n", speed);
492 }
493 
494 static ssize_t fan_min_store(struct device *dev,
495 			     struct device_attribute *attr, const char *buf,
496 			     size_t count)
497 {
498 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
499 	struct nct7802_data *data = dev_get_drvdata(dev);
500 	unsigned long val;
501 	int err;
502 
503 	err = kstrtoul(buf, 10, &val);
504 	if (err < 0)
505 		return err;
506 
507 	err = nct7802_write_fan_min(data, sattr->nr, sattr->index, val);
508 	return err ? : count;
509 }
510 
511 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
512 			  char *buf)
513 {
514 	struct nct7802_data *data = dev_get_drvdata(dev);
515 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
516 	int bit = sattr->index;
517 	unsigned int val;
518 	int ret;
519 
520 	ret = regmap_read(data->regmap, sattr->nr, &val);
521 	if (ret < 0)
522 		return ret;
523 
524 	return sprintf(buf, "%u\n", !!(val & (1 << bit)));
525 }
526 
527 static ssize_t
528 beep_show(struct device *dev, struct device_attribute *attr, char *buf)
529 {
530 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
531 	struct nct7802_data *data = dev_get_drvdata(dev);
532 	unsigned int regval;
533 	int err;
534 
535 	err = regmap_read(data->regmap, sattr->nr, &regval);
536 	if (err)
537 		return err;
538 
539 	return sprintf(buf, "%u\n", !!(regval & (1 << sattr->index)));
540 }
541 
542 static ssize_t
543 beep_store(struct device *dev, struct device_attribute *attr, const char *buf,
544 	   size_t count)
545 {
546 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
547 	struct nct7802_data *data = dev_get_drvdata(dev);
548 	unsigned long val;
549 	int err;
550 
551 	err = kstrtoul(buf, 10, &val);
552 	if (err < 0)
553 		return err;
554 	if (val > 1)
555 		return -EINVAL;
556 
557 	err = regmap_update_bits(data->regmap, sattr->nr, 1 << sattr->index,
558 				 val ? 1 << sattr->index : 0);
559 	return err ? : count;
560 }
561 
562 static SENSOR_DEVICE_ATTR_RW(temp1_type, temp_type, 0);
563 static SENSOR_DEVICE_ATTR_2_RO(temp1_input, temp, 0x01, REG_TEMP_LSB);
564 static SENSOR_DEVICE_ATTR_2_RW(temp1_min, temp, 0x31, 0);
565 static SENSOR_DEVICE_ATTR_2_RW(temp1_max, temp, 0x30, 0);
566 static SENSOR_DEVICE_ATTR_2_RW(temp1_crit, temp, 0x3a, 0);
567 
568 static SENSOR_DEVICE_ATTR_RW(temp2_type, temp_type, 1);
569 static SENSOR_DEVICE_ATTR_2_RO(temp2_input, temp, 0x02, REG_TEMP_LSB);
570 static SENSOR_DEVICE_ATTR_2_RW(temp2_min, temp, 0x33, 0);
571 static SENSOR_DEVICE_ATTR_2_RW(temp2_max, temp, 0x32, 0);
572 static SENSOR_DEVICE_ATTR_2_RW(temp2_crit, temp, 0x3b, 0);
573 
574 static SENSOR_DEVICE_ATTR_RW(temp3_type, temp_type, 2);
575 static SENSOR_DEVICE_ATTR_2_RO(temp3_input, temp, 0x03, REG_TEMP_LSB);
576 static SENSOR_DEVICE_ATTR_2_RW(temp3_min, temp, 0x35, 0);
577 static SENSOR_DEVICE_ATTR_2_RW(temp3_max, temp, 0x34, 0);
578 static SENSOR_DEVICE_ATTR_2_RW(temp3_crit, temp, 0x3c, 0);
579 
580 static SENSOR_DEVICE_ATTR_2_RO(temp4_input, temp, 0x04, 0);
581 static SENSOR_DEVICE_ATTR_2_RW(temp4_min, temp, 0x37, 0);
582 static SENSOR_DEVICE_ATTR_2_RW(temp4_max, temp, 0x36, 0);
583 static SENSOR_DEVICE_ATTR_2_RW(temp4_crit, temp, 0x3d, 0);
584 
585 static SENSOR_DEVICE_ATTR_2_RO(temp5_input, temp, 0x06, REG_TEMP_PECI_LSB);
586 static SENSOR_DEVICE_ATTR_2_RW(temp5_min, temp, 0x39, 0);
587 static SENSOR_DEVICE_ATTR_2_RW(temp5_max, temp, 0x38, 0);
588 static SENSOR_DEVICE_ATTR_2_RW(temp5_crit, temp, 0x3e, 0);
589 
590 static SENSOR_DEVICE_ATTR_2_RO(temp6_input, temp, 0x07, REG_TEMP_PECI_LSB);
591 
592 static SENSOR_DEVICE_ATTR_2_RO(temp1_min_alarm, alarm, 0x18, 0);
593 static SENSOR_DEVICE_ATTR_2_RO(temp2_min_alarm, alarm, 0x18, 1);
594 static SENSOR_DEVICE_ATTR_2_RO(temp3_min_alarm, alarm, 0x18, 2);
595 static SENSOR_DEVICE_ATTR_2_RO(temp4_min_alarm, alarm, 0x18, 3);
596 static SENSOR_DEVICE_ATTR_2_RO(temp5_min_alarm, alarm, 0x18, 4);
597 
598 static SENSOR_DEVICE_ATTR_2_RO(temp1_max_alarm, alarm, 0x19, 0);
599 static SENSOR_DEVICE_ATTR_2_RO(temp2_max_alarm, alarm, 0x19, 1);
600 static SENSOR_DEVICE_ATTR_2_RO(temp3_max_alarm, alarm, 0x19, 2);
601 static SENSOR_DEVICE_ATTR_2_RO(temp4_max_alarm, alarm, 0x19, 3);
602 static SENSOR_DEVICE_ATTR_2_RO(temp5_max_alarm, alarm, 0x19, 4);
603 
604 static SENSOR_DEVICE_ATTR_2_RO(temp1_crit_alarm, alarm, 0x1b, 0);
605 static SENSOR_DEVICE_ATTR_2_RO(temp2_crit_alarm, alarm, 0x1b, 1);
606 static SENSOR_DEVICE_ATTR_2_RO(temp3_crit_alarm, alarm, 0x1b, 2);
607 static SENSOR_DEVICE_ATTR_2_RO(temp4_crit_alarm, alarm, 0x1b, 3);
608 static SENSOR_DEVICE_ATTR_2_RO(temp5_crit_alarm, alarm, 0x1b, 4);
609 
610 static SENSOR_DEVICE_ATTR_2_RO(temp1_fault, alarm, 0x17, 0);
611 static SENSOR_DEVICE_ATTR_2_RO(temp2_fault, alarm, 0x17, 1);
612 static SENSOR_DEVICE_ATTR_2_RO(temp3_fault, alarm, 0x17, 2);
613 
614 static SENSOR_DEVICE_ATTR_2_RW(temp1_beep, beep, 0x5c, 0);
615 static SENSOR_DEVICE_ATTR_2_RW(temp2_beep, beep, 0x5c, 1);
616 static SENSOR_DEVICE_ATTR_2_RW(temp3_beep, beep, 0x5c, 2);
617 static SENSOR_DEVICE_ATTR_2_RW(temp4_beep, beep, 0x5c, 3);
618 static SENSOR_DEVICE_ATTR_2_RW(temp5_beep, beep, 0x5c, 4);
619 static SENSOR_DEVICE_ATTR_2_RW(temp6_beep, beep, 0x5c, 5);
620 
621 static struct attribute *nct7802_temp_attrs[] = {
622 	&sensor_dev_attr_temp1_type.dev_attr.attr,
623 	&sensor_dev_attr_temp1_input.dev_attr.attr,
624 	&sensor_dev_attr_temp1_min.dev_attr.attr,
625 	&sensor_dev_attr_temp1_max.dev_attr.attr,
626 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
627 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
628 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
629 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
630 	&sensor_dev_attr_temp1_fault.dev_attr.attr,
631 	&sensor_dev_attr_temp1_beep.dev_attr.attr,
632 
633 	&sensor_dev_attr_temp2_type.dev_attr.attr,		/* 10 */
634 	&sensor_dev_attr_temp2_input.dev_attr.attr,
635 	&sensor_dev_attr_temp2_min.dev_attr.attr,
636 	&sensor_dev_attr_temp2_max.dev_attr.attr,
637 	&sensor_dev_attr_temp2_crit.dev_attr.attr,
638 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
639 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
640 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
641 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
642 	&sensor_dev_attr_temp2_beep.dev_attr.attr,
643 
644 	&sensor_dev_attr_temp3_type.dev_attr.attr,		/* 20 */
645 	&sensor_dev_attr_temp3_input.dev_attr.attr,
646 	&sensor_dev_attr_temp3_min.dev_attr.attr,
647 	&sensor_dev_attr_temp3_max.dev_attr.attr,
648 	&sensor_dev_attr_temp3_crit.dev_attr.attr,
649 	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
650 	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
651 	&sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
652 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
653 	&sensor_dev_attr_temp3_beep.dev_attr.attr,
654 
655 	&sensor_dev_attr_temp4_input.dev_attr.attr,		/* 30 */
656 	&sensor_dev_attr_temp4_min.dev_attr.attr,
657 	&sensor_dev_attr_temp4_max.dev_attr.attr,
658 	&sensor_dev_attr_temp4_crit.dev_attr.attr,
659 	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
660 	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
661 	&sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
662 	&sensor_dev_attr_temp4_beep.dev_attr.attr,
663 
664 	&sensor_dev_attr_temp5_input.dev_attr.attr,		/* 38 */
665 	&sensor_dev_attr_temp5_min.dev_attr.attr,
666 	&sensor_dev_attr_temp5_max.dev_attr.attr,
667 	&sensor_dev_attr_temp5_crit.dev_attr.attr,
668 	&sensor_dev_attr_temp5_min_alarm.dev_attr.attr,
669 	&sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
670 	&sensor_dev_attr_temp5_crit_alarm.dev_attr.attr,
671 	&sensor_dev_attr_temp5_beep.dev_attr.attr,
672 
673 	&sensor_dev_attr_temp6_input.dev_attr.attr,		/* 46 */
674 	&sensor_dev_attr_temp6_beep.dev_attr.attr,
675 
676 	NULL
677 };
678 
679 static umode_t nct7802_temp_is_visible(struct kobject *kobj,
680 				       struct attribute *attr, int index)
681 {
682 	struct device *dev = kobj_to_dev(kobj);
683 	struct nct7802_data *data = dev_get_drvdata(dev);
684 	unsigned int reg;
685 	int err;
686 
687 	err = regmap_read(data->regmap, REG_MODE, &reg);
688 	if (err < 0)
689 		return 0;
690 
691 	if (index < 10 &&
692 	    (reg & 03) != 0x01 && (reg & 0x03) != 0x02)		/* RD1 */
693 		return 0;
694 
695 	if (index >= 10 && index < 20 &&
696 	    (reg & 0x0c) != 0x04 && (reg & 0x0c) != 0x08)	/* RD2 */
697 		return 0;
698 	if (index >= 20 && index < 30 && (reg & 0x30) != 0x20)	/* RD3 */
699 		return 0;
700 
701 	if (index >= 30 && index < 38)				/* local */
702 		return attr->mode;
703 
704 	err = regmap_read(data->regmap, REG_PECI_ENABLE, &reg);
705 	if (err < 0)
706 		return 0;
707 
708 	if (index >= 38 && index < 46 && !(reg & 0x01))		/* PECI 0 */
709 		return 0;
710 
711 	if (index >= 0x46 && (!(reg & 0x02)))			/* PECI 1 */
712 		return 0;
713 
714 	return attr->mode;
715 }
716 
717 static const struct attribute_group nct7802_temp_group = {
718 	.attrs = nct7802_temp_attrs,
719 	.is_visible = nct7802_temp_is_visible,
720 };
721 
722 static SENSOR_DEVICE_ATTR_2_RO(in0_input, in, 0, 0);
723 static SENSOR_DEVICE_ATTR_2_RW(in0_min, in, 0, 1);
724 static SENSOR_DEVICE_ATTR_2_RW(in0_max, in, 0, 2);
725 static SENSOR_DEVICE_ATTR_2_RO(in0_alarm, in_alarm, 0, 3);
726 static SENSOR_DEVICE_ATTR_2_RW(in0_beep, beep, 0x5a, 3);
727 
728 static SENSOR_DEVICE_ATTR_2_RO(in1_input, in, 1, 0);
729 
730 static SENSOR_DEVICE_ATTR_2_RO(in2_input, in, 2, 0);
731 static SENSOR_DEVICE_ATTR_2_RW(in2_min, in, 2, 1);
732 static SENSOR_DEVICE_ATTR_2_RW(in2_max, in, 2, 2);
733 static SENSOR_DEVICE_ATTR_2_RO(in2_alarm, in_alarm, 2, 0);
734 static SENSOR_DEVICE_ATTR_2_RW(in2_beep, beep, 0x5a, 0);
735 
736 static SENSOR_DEVICE_ATTR_2_RO(in3_input, in, 3, 0);
737 static SENSOR_DEVICE_ATTR_2_RW(in3_min, in, 3, 1);
738 static SENSOR_DEVICE_ATTR_2_RW(in3_max, in, 3, 2);
739 static SENSOR_DEVICE_ATTR_2_RO(in3_alarm, in_alarm, 3, 1);
740 static SENSOR_DEVICE_ATTR_2_RW(in3_beep, beep, 0x5a, 1);
741 
742 static SENSOR_DEVICE_ATTR_2_RO(in4_input, in, 4, 0);
743 static SENSOR_DEVICE_ATTR_2_RW(in4_min, in, 4, 1);
744 static SENSOR_DEVICE_ATTR_2_RW(in4_max, in, 4, 2);
745 static SENSOR_DEVICE_ATTR_2_RO(in4_alarm, in_alarm, 4, 2);
746 static SENSOR_DEVICE_ATTR_2_RW(in4_beep, beep, 0x5a, 2);
747 
748 static struct attribute *nct7802_in_attrs[] = {
749 	&sensor_dev_attr_in0_input.dev_attr.attr,
750 	&sensor_dev_attr_in0_min.dev_attr.attr,
751 	&sensor_dev_attr_in0_max.dev_attr.attr,
752 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
753 	&sensor_dev_attr_in0_beep.dev_attr.attr,
754 
755 	&sensor_dev_attr_in1_input.dev_attr.attr,	/* 5 */
756 
757 	&sensor_dev_attr_in2_input.dev_attr.attr,	/* 6 */
758 	&sensor_dev_attr_in2_min.dev_attr.attr,
759 	&sensor_dev_attr_in2_max.dev_attr.attr,
760 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
761 	&sensor_dev_attr_in2_beep.dev_attr.attr,
762 
763 	&sensor_dev_attr_in3_input.dev_attr.attr,	/* 11 */
764 	&sensor_dev_attr_in3_min.dev_attr.attr,
765 	&sensor_dev_attr_in3_max.dev_attr.attr,
766 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
767 	&sensor_dev_attr_in3_beep.dev_attr.attr,
768 
769 	&sensor_dev_attr_in4_input.dev_attr.attr,	/* 16 */
770 	&sensor_dev_attr_in4_min.dev_attr.attr,
771 	&sensor_dev_attr_in4_max.dev_attr.attr,
772 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
773 	&sensor_dev_attr_in4_beep.dev_attr.attr,
774 
775 	NULL,
776 };
777 
778 static umode_t nct7802_in_is_visible(struct kobject *kobj,
779 				     struct attribute *attr, int index)
780 {
781 	struct device *dev = kobj_to_dev(kobj);
782 	struct nct7802_data *data = dev_get_drvdata(dev);
783 	unsigned int reg;
784 	int err;
785 
786 	if (index < 6)						/* VCC, VCORE */
787 		return attr->mode;
788 
789 	err = regmap_read(data->regmap, REG_MODE, &reg);
790 	if (err < 0)
791 		return 0;
792 
793 	if (index >= 6 && index < 11 && (reg & 0x03) != 0x03)	/* VSEN1 */
794 		return 0;
795 	if (index >= 11 && index < 16 && (reg & 0x0c) != 0x0c)	/* VSEN2 */
796 		return 0;
797 	if (index >= 16 && (reg & 0x30) != 0x30)		/* VSEN3 */
798 		return 0;
799 
800 	return attr->mode;
801 }
802 
803 static const struct attribute_group nct7802_in_group = {
804 	.attrs = nct7802_in_attrs,
805 	.is_visible = nct7802_in_is_visible,
806 };
807 
808 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0x10);
809 static SENSOR_DEVICE_ATTR_2_RW(fan1_min, fan_min, 0x49, 0x4c);
810 static SENSOR_DEVICE_ATTR_2_RO(fan1_alarm, alarm, 0x1a, 0);
811 static SENSOR_DEVICE_ATTR_2_RW(fan1_beep, beep, 0x5b, 0);
812 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 0x11);
813 static SENSOR_DEVICE_ATTR_2_RW(fan2_min, fan_min, 0x4a, 0x4d);
814 static SENSOR_DEVICE_ATTR_2_RO(fan2_alarm, alarm, 0x1a, 1);
815 static SENSOR_DEVICE_ATTR_2_RW(fan2_beep, beep, 0x5b, 1);
816 static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 0x12);
817 static SENSOR_DEVICE_ATTR_2_RW(fan3_min, fan_min, 0x4b, 0x4e);
818 static SENSOR_DEVICE_ATTR_2_RO(fan3_alarm, alarm, 0x1a, 2);
819 static SENSOR_DEVICE_ATTR_2_RW(fan3_beep, beep, 0x5b, 2);
820 
821 /* 7.2.89 Fan Control Output Type */
822 static SENSOR_DEVICE_ATTR_RO(pwm1_mode, pwm_mode, 0);
823 static SENSOR_DEVICE_ATTR_RO(pwm2_mode, pwm_mode, 1);
824 static SENSOR_DEVICE_ATTR_RO(pwm3_mode, pwm_mode, 2);
825 
826 /* 7.2.91... Fan Control Output Value */
827 static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, REG_PWM(0));
828 static SENSOR_DEVICE_ATTR_RW(pwm2, pwm, REG_PWM(1));
829 static SENSOR_DEVICE_ATTR_RW(pwm3, pwm, REG_PWM(2));
830 
831 /* 7.2.95... Temperature to Fan mapping Relationships Register */
832 static SENSOR_DEVICE_ATTR_RW(pwm1_enable, pwm_enable, 0);
833 static SENSOR_DEVICE_ATTR_RW(pwm2_enable, pwm_enable, 1);
834 static SENSOR_DEVICE_ATTR_RW(pwm3_enable, pwm_enable, 2);
835 
836 static struct attribute *nct7802_fan_attrs[] = {
837 	&sensor_dev_attr_fan1_input.dev_attr.attr,
838 	&sensor_dev_attr_fan1_min.dev_attr.attr,
839 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
840 	&sensor_dev_attr_fan1_beep.dev_attr.attr,
841 	&sensor_dev_attr_fan2_input.dev_attr.attr,
842 	&sensor_dev_attr_fan2_min.dev_attr.attr,
843 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
844 	&sensor_dev_attr_fan2_beep.dev_attr.attr,
845 	&sensor_dev_attr_fan3_input.dev_attr.attr,
846 	&sensor_dev_attr_fan3_min.dev_attr.attr,
847 	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
848 	&sensor_dev_attr_fan3_beep.dev_attr.attr,
849 
850 	NULL
851 };
852 
853 static umode_t nct7802_fan_is_visible(struct kobject *kobj,
854 				      struct attribute *attr, int index)
855 {
856 	struct device *dev = kobj_to_dev(kobj);
857 	struct nct7802_data *data = dev_get_drvdata(dev);
858 	int fan = index / 4;	/* 4 attributes per fan */
859 	unsigned int reg;
860 	int err;
861 
862 	err = regmap_read(data->regmap, REG_FAN_ENABLE, &reg);
863 	if (err < 0 || !(reg & (1 << fan)))
864 		return 0;
865 
866 	return attr->mode;
867 }
868 
869 static const struct attribute_group nct7802_fan_group = {
870 	.attrs = nct7802_fan_attrs,
871 	.is_visible = nct7802_fan_is_visible,
872 };
873 
874 static struct attribute *nct7802_pwm_attrs[] = {
875 	&sensor_dev_attr_pwm1_enable.dev_attr.attr,
876 	&sensor_dev_attr_pwm1_mode.dev_attr.attr,
877 	&sensor_dev_attr_pwm1.dev_attr.attr,
878 	&sensor_dev_attr_pwm2_enable.dev_attr.attr,
879 	&sensor_dev_attr_pwm2_mode.dev_attr.attr,
880 	&sensor_dev_attr_pwm2.dev_attr.attr,
881 	&sensor_dev_attr_pwm3_enable.dev_attr.attr,
882 	&sensor_dev_attr_pwm3_mode.dev_attr.attr,
883 	&sensor_dev_attr_pwm3.dev_attr.attr,
884 	NULL
885 };
886 
887 static const struct attribute_group nct7802_pwm_group = {
888 	.attrs = nct7802_pwm_attrs,
889 };
890 
891 /* 7.2.115... 0x80-0x83, 0x84 Temperature (X-axis) transition */
892 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point1_temp, temp, 0x80, 0);
893 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point2_temp, temp, 0x81, 0);
894 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point3_temp, temp, 0x82, 0);
895 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point4_temp, temp, 0x83, 0);
896 static SENSOR_DEVICE_ATTR_2_RW(pwm1_auto_point5_temp, temp, 0x84, 0);
897 
898 /* 7.2.120... 0x85-0x88 PWM (Y-axis) transition */
899 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_pwm, pwm, 0x85);
900 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_pwm, pwm, 0x86);
901 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_pwm, pwm, 0x87);
902 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_pwm, pwm, 0x88);
903 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point5_pwm, pwm, 0);
904 
905 /* 7.2.124 Table 2 X-axis Transition Point 1 Register */
906 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point1_temp, temp, 0x90, 0);
907 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point2_temp, temp, 0x91, 0);
908 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point3_temp, temp, 0x92, 0);
909 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point4_temp, temp, 0x93, 0);
910 static SENSOR_DEVICE_ATTR_2_RW(pwm2_auto_point5_temp, temp, 0x94, 0);
911 
912 /* 7.2.129 Table 2 Y-axis Transition Point 1 Register */
913 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point1_pwm, pwm, 0x95);
914 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point2_pwm, pwm, 0x96);
915 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point3_pwm, pwm, 0x97);
916 static SENSOR_DEVICE_ATTR_RW(pwm2_auto_point4_pwm, pwm, 0x98);
917 static SENSOR_DEVICE_ATTR_RO(pwm2_auto_point5_pwm, pwm, 0);
918 
919 /* 7.2.133 Table 3 X-axis Transition Point 1 Register */
920 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point1_temp, temp, 0xA0, 0);
921 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point2_temp, temp, 0xA1, 0);
922 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point3_temp, temp, 0xA2, 0);
923 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point4_temp, temp, 0xA3, 0);
924 static SENSOR_DEVICE_ATTR_2_RW(pwm3_auto_point5_temp, temp, 0xA4, 0);
925 
926 /* 7.2.138 Table 3 Y-axis Transition Point 1 Register */
927 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point1_pwm, pwm, 0xA5);
928 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point2_pwm, pwm, 0xA6);
929 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point3_pwm, pwm, 0xA7);
930 static SENSOR_DEVICE_ATTR_RW(pwm3_auto_point4_pwm, pwm, 0xA8);
931 static SENSOR_DEVICE_ATTR_RO(pwm3_auto_point5_pwm, pwm, 0);
932 
933 static struct attribute *nct7802_auto_point_attrs[] = {
934 	&sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr,
935 	&sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr,
936 	&sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr,
937 	&sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr,
938 	&sensor_dev_attr_pwm1_auto_point5_temp.dev_attr.attr,
939 
940 	&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
941 	&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
942 	&sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
943 	&sensor_dev_attr_pwm1_auto_point4_pwm.dev_attr.attr,
944 	&sensor_dev_attr_pwm1_auto_point5_pwm.dev_attr.attr,
945 
946 	&sensor_dev_attr_pwm2_auto_point1_temp.dev_attr.attr,
947 	&sensor_dev_attr_pwm2_auto_point2_temp.dev_attr.attr,
948 	&sensor_dev_attr_pwm2_auto_point3_temp.dev_attr.attr,
949 	&sensor_dev_attr_pwm2_auto_point4_temp.dev_attr.attr,
950 	&sensor_dev_attr_pwm2_auto_point5_temp.dev_attr.attr,
951 
952 	&sensor_dev_attr_pwm2_auto_point1_pwm.dev_attr.attr,
953 	&sensor_dev_attr_pwm2_auto_point2_pwm.dev_attr.attr,
954 	&sensor_dev_attr_pwm2_auto_point3_pwm.dev_attr.attr,
955 	&sensor_dev_attr_pwm2_auto_point4_pwm.dev_attr.attr,
956 	&sensor_dev_attr_pwm2_auto_point5_pwm.dev_attr.attr,
957 
958 	&sensor_dev_attr_pwm3_auto_point1_temp.dev_attr.attr,
959 	&sensor_dev_attr_pwm3_auto_point2_temp.dev_attr.attr,
960 	&sensor_dev_attr_pwm3_auto_point3_temp.dev_attr.attr,
961 	&sensor_dev_attr_pwm3_auto_point4_temp.dev_attr.attr,
962 	&sensor_dev_attr_pwm3_auto_point5_temp.dev_attr.attr,
963 
964 	&sensor_dev_attr_pwm3_auto_point1_pwm.dev_attr.attr,
965 	&sensor_dev_attr_pwm3_auto_point2_pwm.dev_attr.attr,
966 	&sensor_dev_attr_pwm3_auto_point3_pwm.dev_attr.attr,
967 	&sensor_dev_attr_pwm3_auto_point4_pwm.dev_attr.attr,
968 	&sensor_dev_attr_pwm3_auto_point5_pwm.dev_attr.attr,
969 
970 	NULL
971 };
972 
973 static const struct attribute_group nct7802_auto_point_group = {
974 	.attrs = nct7802_auto_point_attrs,
975 };
976 
977 static const struct attribute_group *nct7802_groups[] = {
978 	&nct7802_temp_group,
979 	&nct7802_in_group,
980 	&nct7802_fan_group,
981 	&nct7802_pwm_group,
982 	&nct7802_auto_point_group,
983 	NULL
984 };
985 
986 static int nct7802_detect(struct i2c_client *client,
987 			  struct i2c_board_info *info)
988 {
989 	int reg;
990 
991 	/*
992 	 * Chip identification registers are only available in bank 0,
993 	 * so only attempt chip detection if bank 0 is selected
994 	 */
995 	reg = i2c_smbus_read_byte_data(client, REG_BANK);
996 	if (reg != 0x00)
997 		return -ENODEV;
998 
999 	reg = i2c_smbus_read_byte_data(client, REG_VENDOR_ID);
1000 	if (reg != 0x50)
1001 		return -ENODEV;
1002 
1003 	reg = i2c_smbus_read_byte_data(client, REG_CHIP_ID);
1004 	if (reg != 0xc3)
1005 		return -ENODEV;
1006 
1007 	reg = i2c_smbus_read_byte_data(client, REG_VERSION_ID);
1008 	if (reg < 0 || (reg & 0xf0) != 0x20)
1009 		return -ENODEV;
1010 
1011 	/* Also validate lower bits of voltage and temperature registers */
1012 	reg = i2c_smbus_read_byte_data(client, REG_TEMP_LSB);
1013 	if (reg < 0 || (reg & 0x1f))
1014 		return -ENODEV;
1015 
1016 	reg = i2c_smbus_read_byte_data(client, REG_TEMP_PECI_LSB);
1017 	if (reg < 0 || (reg & 0x3f))
1018 		return -ENODEV;
1019 
1020 	reg = i2c_smbus_read_byte_data(client, REG_VOLTAGE_LOW);
1021 	if (reg < 0 || (reg & 0x3f))
1022 		return -ENODEV;
1023 
1024 	strlcpy(info->type, "nct7802", I2C_NAME_SIZE);
1025 	return 0;
1026 }
1027 
1028 static bool nct7802_regmap_is_volatile(struct device *dev, unsigned int reg)
1029 {
1030 	return (reg != REG_BANK && reg <= 0x20) ||
1031 		(reg >= REG_PWM(0) && reg <= REG_PWM(2));
1032 }
1033 
1034 static const struct regmap_config nct7802_regmap_config = {
1035 	.reg_bits = 8,
1036 	.val_bits = 8,
1037 	.cache_type = REGCACHE_RBTREE,
1038 	.volatile_reg = nct7802_regmap_is_volatile,
1039 };
1040 
1041 static int nct7802_init_chip(struct nct7802_data *data)
1042 {
1043 	int err;
1044 
1045 	/* Enable ADC */
1046 	err = regmap_update_bits(data->regmap, REG_START, 0x01, 0x01);
1047 	if (err)
1048 		return err;
1049 
1050 	/* Enable local temperature sensor */
1051 	err = regmap_update_bits(data->regmap, REG_MODE, 0x40, 0x40);
1052 	if (err)
1053 		return err;
1054 
1055 	/* Enable Vcore and VCC voltage monitoring */
1056 	return regmap_update_bits(data->regmap, REG_VMON_ENABLE, 0x03, 0x03);
1057 }
1058 
1059 static int nct7802_probe(struct i2c_client *client)
1060 {
1061 	struct device *dev = &client->dev;
1062 	struct nct7802_data *data;
1063 	struct device *hwmon_dev;
1064 	int ret;
1065 
1066 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
1067 	if (data == NULL)
1068 		return -ENOMEM;
1069 
1070 	data->regmap = devm_regmap_init_i2c(client, &nct7802_regmap_config);
1071 	if (IS_ERR(data->regmap))
1072 		return PTR_ERR(data->regmap);
1073 
1074 	mutex_init(&data->access_lock);
1075 	mutex_init(&data->in_alarm_lock);
1076 
1077 	ret = nct7802_init_chip(data);
1078 	if (ret < 0)
1079 		return ret;
1080 
1081 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
1082 							   data,
1083 							   nct7802_groups);
1084 	return PTR_ERR_OR_ZERO(hwmon_dev);
1085 }
1086 
1087 static const unsigned short nct7802_address_list[] = {
1088 	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END
1089 };
1090 
1091 static const struct i2c_device_id nct7802_idtable[] = {
1092 	{ "nct7802", 0 },
1093 	{ }
1094 };
1095 MODULE_DEVICE_TABLE(i2c, nct7802_idtable);
1096 
1097 static struct i2c_driver nct7802_driver = {
1098 	.class = I2C_CLASS_HWMON,
1099 	.driver = {
1100 		.name = DRVNAME,
1101 	},
1102 	.detect = nct7802_detect,
1103 	.probe_new = nct7802_probe,
1104 	.id_table = nct7802_idtable,
1105 	.address_list = nct7802_address_list,
1106 };
1107 
1108 module_i2c_driver(nct7802_driver);
1109 
1110 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
1111 MODULE_DESCRIPTION("NCT7802Y Hardware Monitoring Driver");
1112 MODULE_LICENSE("GPL v2");
1113