xref: /linux/drivers/hwmon/nct7802.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /*
2  * nct7802 - Driver for Nuvoton NCT7802Y
3  *
4  * Copyright (C) 2014  Guenter Roeck <linux@roeck-us.net>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 
19 #include <linux/err.h>
20 #include <linux/i2c.h>
21 #include <linux/init.h>
22 #include <linux/hwmon.h>
23 #include <linux/hwmon-sysfs.h>
24 #include <linux/jiffies.h>
25 #include <linux/module.h>
26 #include <linux/mutex.h>
27 #include <linux/regmap.h>
28 #include <linux/slab.h>
29 
30 #define DRVNAME "nct7802"
31 
32 static const u8 REG_VOLTAGE[5] = { 0x09, 0x0a, 0x0c, 0x0d, 0x0e };
33 
34 static const u8 REG_VOLTAGE_LIMIT_LSB[2][5] = {
35 	{ 0x40, 0x00, 0x42, 0x44, 0x46 },
36 	{ 0x3f, 0x00, 0x41, 0x43, 0x45 },
37 };
38 
39 static const u8 REG_VOLTAGE_LIMIT_MSB[5] = { 0x48, 0x00, 0x47, 0x47, 0x48 };
40 
41 static const u8 REG_VOLTAGE_LIMIT_MSB_SHIFT[2][5] = {
42 	{ 0, 0, 4, 0, 4 },
43 	{ 2, 0, 6, 2, 6 },
44 };
45 
46 #define REG_BANK		0x00
47 #define REG_TEMP_LSB		0x05
48 #define REG_TEMP_PECI_LSB	0x08
49 #define REG_VOLTAGE_LOW		0x0f
50 #define REG_FANCOUNT_LOW	0x13
51 #define REG_START		0x21
52 #define REG_MODE		0x22
53 #define REG_PECI_ENABLE		0x23
54 #define REG_FAN_ENABLE		0x24
55 #define REG_VMON_ENABLE		0x25
56 #define REG_VENDOR_ID		0xfd
57 #define REG_CHIP_ID		0xfe
58 #define REG_VERSION_ID		0xff
59 
60 /*
61  * Data structures and manipulation thereof
62  */
63 
64 struct nct7802_data {
65 	struct regmap *regmap;
66 	struct mutex access_lock; /* for multi-byte read and write operations */
67 };
68 
69 static int nct7802_read_temp(struct nct7802_data *data,
70 			     u8 reg_temp, u8 reg_temp_low, int *temp)
71 {
72 	unsigned int t1, t2 = 0;
73 	int err;
74 
75 	*temp = 0;
76 
77 	mutex_lock(&data->access_lock);
78 	err = regmap_read(data->regmap, reg_temp, &t1);
79 	if (err < 0)
80 		goto abort;
81 	t1 <<= 8;
82 	if (reg_temp_low) {	/* 11 bit data */
83 		err = regmap_read(data->regmap, reg_temp_low, &t2);
84 		if (err < 0)
85 			goto abort;
86 	}
87 	t1 |= t2 & 0xe0;
88 	*temp = (s16)t1 / 32 * 125;
89 abort:
90 	mutex_unlock(&data->access_lock);
91 	return err;
92 }
93 
94 static int nct7802_read_fan(struct nct7802_data *data, u8 reg_fan)
95 {
96 	unsigned int f1, f2;
97 	int ret;
98 
99 	mutex_lock(&data->access_lock);
100 	ret = regmap_read(data->regmap, reg_fan, &f1);
101 	if (ret < 0)
102 		goto abort;
103 	ret = regmap_read(data->regmap, REG_FANCOUNT_LOW, &f2);
104 	if (ret < 0)
105 		goto abort;
106 	ret = (f1 << 5) | (f2 >> 3);
107 	/* convert fan count to rpm */
108 	if (ret == 0x1fff)	/* maximum value, assume fan is stopped */
109 		ret = 0;
110 	else if (ret)
111 		ret = DIV_ROUND_CLOSEST(1350000U, ret);
112 abort:
113 	mutex_unlock(&data->access_lock);
114 	return ret;
115 }
116 
117 static int nct7802_read_fan_min(struct nct7802_data *data, u8 reg_fan_low,
118 				u8 reg_fan_high)
119 {
120 	unsigned int f1, f2;
121 	int ret;
122 
123 	mutex_lock(&data->access_lock);
124 	ret = regmap_read(data->regmap, reg_fan_low, &f1);
125 	if (ret < 0)
126 		goto abort;
127 	ret = regmap_read(data->regmap, reg_fan_high, &f2);
128 	if (ret < 0)
129 		goto abort;
130 	ret = f1 | ((f2 & 0xf8) << 5);
131 	/* convert fan count to rpm */
132 	if (ret == 0x1fff)	/* maximum value, assume no limit */
133 		ret = 0;
134 	else if (ret)
135 		ret = DIV_ROUND_CLOSEST(1350000U, ret);
136 abort:
137 	mutex_unlock(&data->access_lock);
138 	return ret;
139 }
140 
141 static int nct7802_write_fan_min(struct nct7802_data *data, u8 reg_fan_low,
142 				 u8 reg_fan_high, unsigned int limit)
143 {
144 	int err;
145 
146 	if (limit)
147 		limit = DIV_ROUND_CLOSEST(1350000U, limit);
148 	else
149 		limit = 0x1fff;
150 	limit = clamp_val(limit, 0, 0x1fff);
151 
152 	mutex_lock(&data->access_lock);
153 	err = regmap_write(data->regmap, reg_fan_low, limit & 0xff);
154 	if (err < 0)
155 		goto abort;
156 
157 	err = regmap_write(data->regmap, reg_fan_high, (limit & 0x1f00) >> 5);
158 abort:
159 	mutex_unlock(&data->access_lock);
160 	return err;
161 }
162 
163 static u8 nct7802_vmul[] = { 4, 2, 2, 2, 2 };
164 
165 static int nct7802_read_voltage(struct nct7802_data *data, int nr, int index)
166 {
167 	unsigned int v1, v2;
168 	int ret;
169 
170 	mutex_lock(&data->access_lock);
171 	if (index == 0) {	/* voltage */
172 		ret = regmap_read(data->regmap, REG_VOLTAGE[nr], &v1);
173 		if (ret < 0)
174 			goto abort;
175 		ret = regmap_read(data->regmap, REG_VOLTAGE_LOW, &v2);
176 		if (ret < 0)
177 			goto abort;
178 		ret = ((v1 << 2) | (v2 >> 6)) * nct7802_vmul[nr];
179 	}  else {	/* limit */
180 		int shift = 8 - REG_VOLTAGE_LIMIT_MSB_SHIFT[index - 1][nr];
181 
182 		ret = regmap_read(data->regmap,
183 				  REG_VOLTAGE_LIMIT_LSB[index - 1][nr], &v1);
184 		if (ret < 0)
185 			goto abort;
186 		ret = regmap_read(data->regmap, REG_VOLTAGE_LIMIT_MSB[nr],
187 				  &v2);
188 		if (ret < 0)
189 			goto abort;
190 		ret = (v1 | ((v2 << shift) & 0x300)) * nct7802_vmul[nr];
191 	}
192 abort:
193 	mutex_unlock(&data->access_lock);
194 	return ret;
195 }
196 
197 static int nct7802_write_voltage(struct nct7802_data *data, int nr, int index,
198 				 unsigned int voltage)
199 {
200 	int shift = 8 - REG_VOLTAGE_LIMIT_MSB_SHIFT[index - 1][nr];
201 	int err;
202 
203 	voltage = DIV_ROUND_CLOSEST(voltage, nct7802_vmul[nr]);
204 	voltage = clamp_val(voltage, 0, 0x3ff);
205 
206 	mutex_lock(&data->access_lock);
207 	err = regmap_write(data->regmap,
208 			   REG_VOLTAGE_LIMIT_LSB[index - 1][nr],
209 			   voltage & 0xff);
210 	if (err < 0)
211 		goto abort;
212 
213 	err = regmap_update_bits(data->regmap, REG_VOLTAGE_LIMIT_MSB[nr],
214 				 0x0300 >> shift, (voltage & 0x0300) >> shift);
215 abort:
216 	mutex_unlock(&data->access_lock);
217 	return err;
218 }
219 
220 static ssize_t show_in(struct device *dev, struct device_attribute *attr,
221 		       char *buf)
222 {
223 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
224 	struct nct7802_data *data = dev_get_drvdata(dev);
225 	int voltage;
226 
227 	voltage = nct7802_read_voltage(data, sattr->nr, sattr->index);
228 	if (voltage < 0)
229 		return voltage;
230 
231 	return sprintf(buf, "%d\n", voltage);
232 }
233 
234 static ssize_t store_in(struct device *dev, struct device_attribute *attr,
235 			const char *buf, size_t count)
236 {
237 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
238 	struct nct7802_data *data = dev_get_drvdata(dev);
239 	int index = sattr->index;
240 	int nr = sattr->nr;
241 	unsigned long val;
242 	int err;
243 
244 	err = kstrtoul(buf, 10, &val);
245 	if (err < 0)
246 		return err;
247 
248 	err = nct7802_write_voltage(data, nr, index, val);
249 	return err ? : count;
250 }
251 
252 static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
253 			 char *buf)
254 {
255 	struct nct7802_data *data = dev_get_drvdata(dev);
256 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
257 	int err, temp;
258 
259 	err = nct7802_read_temp(data, sattr->nr, sattr->index, &temp);
260 	if (err < 0)
261 		return err;
262 
263 	return sprintf(buf, "%d\n", temp);
264 }
265 
266 static ssize_t store_temp(struct device *dev, struct device_attribute *attr,
267 			  const char *buf, size_t count)
268 {
269 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
270 	struct nct7802_data *data = dev_get_drvdata(dev);
271 	int nr = sattr->nr;
272 	long val;
273 	int err;
274 
275 	err = kstrtol(buf, 10, &val);
276 	if (err < 0)
277 		return err;
278 
279 	val = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
280 
281 	err = regmap_write(data->regmap, nr, val & 0xff);
282 	return err ? : count;
283 }
284 
285 static ssize_t show_fan(struct device *dev, struct device_attribute *attr,
286 			char *buf)
287 {
288 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
289 	struct nct7802_data *data = dev_get_drvdata(dev);
290 	int speed;
291 
292 	speed = nct7802_read_fan(data, sattr->index);
293 	if (speed < 0)
294 		return speed;
295 
296 	return sprintf(buf, "%d\n", speed);
297 }
298 
299 static ssize_t show_fan_min(struct device *dev, struct device_attribute *attr,
300 			    char *buf)
301 {
302 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
303 	struct nct7802_data *data = dev_get_drvdata(dev);
304 	int speed;
305 
306 	speed = nct7802_read_fan_min(data, sattr->nr, sattr->index);
307 	if (speed < 0)
308 		return speed;
309 
310 	return sprintf(buf, "%d\n", speed);
311 }
312 
313 static ssize_t store_fan_min(struct device *dev, struct device_attribute *attr,
314 			     const char *buf, size_t count)
315 {
316 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
317 	struct nct7802_data *data = dev_get_drvdata(dev);
318 	unsigned long val;
319 	int err;
320 
321 	err = kstrtoul(buf, 10, &val);
322 	if (err < 0)
323 		return err;
324 
325 	err = nct7802_write_fan_min(data, sattr->nr, sattr->index, val);
326 	return err ? : count;
327 }
328 
329 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
330 			  char *buf)
331 {
332 	struct nct7802_data *data = dev_get_drvdata(dev);
333 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
334 	int bit = sattr->index;
335 	unsigned int val;
336 	int ret;
337 
338 	ret = regmap_read(data->regmap, sattr->nr, &val);
339 	if (ret < 0)
340 		return ret;
341 
342 	return sprintf(buf, "%u\n", !!(val & (1 << bit)));
343 }
344 
345 static ssize_t
346 show_beep(struct device *dev, struct device_attribute *attr, char *buf)
347 {
348 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
349 	struct nct7802_data *data = dev_get_drvdata(dev);
350 	unsigned int regval;
351 	int err;
352 
353 	err = regmap_read(data->regmap, sattr->nr, &regval);
354 	if (err)
355 		return err;
356 
357 	return sprintf(buf, "%u\n", !!(regval & (1 << sattr->index)));
358 }
359 
360 static ssize_t
361 store_beep(struct device *dev, struct device_attribute *attr, const char *buf,
362 	   size_t count)
363 {
364 	struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr);
365 	struct nct7802_data *data = dev_get_drvdata(dev);
366 	unsigned long val;
367 	int err;
368 
369 	err = kstrtoul(buf, 10, &val);
370 	if (err < 0)
371 		return err;
372 	if (val > 1)
373 		return -EINVAL;
374 
375 	err = regmap_update_bits(data->regmap, sattr->nr, 1 << sattr->index,
376 				 val ? 1 << sattr->index : 0);
377 	return err ? : count;
378 }
379 
380 static SENSOR_DEVICE_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0x01,
381 			    REG_TEMP_LSB);
382 static SENSOR_DEVICE_ATTR_2(temp1_min, S_IRUGO | S_IWUSR, show_temp,
383 			    store_temp, 0x31, 0);
384 static SENSOR_DEVICE_ATTR_2(temp1_max, S_IRUGO | S_IWUSR, show_temp,
385 			    store_temp, 0x30, 0);
386 static SENSOR_DEVICE_ATTR_2(temp1_crit, S_IRUGO | S_IWUSR, show_temp,
387 			    store_temp, 0x3a, 0);
388 
389 static SENSOR_DEVICE_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 0x02,
390 			    REG_TEMP_LSB);
391 static SENSOR_DEVICE_ATTR_2(temp2_min, S_IRUGO | S_IWUSR, show_temp,
392 			    store_temp, 0x33, 0);
393 static SENSOR_DEVICE_ATTR_2(temp2_max, S_IRUGO | S_IWUSR, show_temp,
394 			    store_temp, 0x32, 0);
395 static SENSOR_DEVICE_ATTR_2(temp2_crit, S_IRUGO | S_IWUSR, show_temp,
396 			    store_temp, 0x3b, 0);
397 
398 static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp, NULL, 0x03,
399 			    REG_TEMP_LSB);
400 static SENSOR_DEVICE_ATTR_2(temp3_min, S_IRUGO | S_IWUSR, show_temp,
401 			    store_temp, 0x35, 0);
402 static SENSOR_DEVICE_ATTR_2(temp3_max, S_IRUGO | S_IWUSR, show_temp,
403 			    store_temp, 0x34, 0);
404 static SENSOR_DEVICE_ATTR_2(temp3_crit, S_IRUGO | S_IWUSR, show_temp,
405 			    store_temp, 0x3c, 0);
406 
407 static SENSOR_DEVICE_ATTR_2(temp4_input, S_IRUGO, show_temp, NULL, 0x04, 0);
408 static SENSOR_DEVICE_ATTR_2(temp4_min, S_IRUGO | S_IWUSR, show_temp,
409 			    store_temp, 0x37, 0);
410 static SENSOR_DEVICE_ATTR_2(temp4_max, S_IRUGO | S_IWUSR, show_temp,
411 			    store_temp, 0x36, 0);
412 static SENSOR_DEVICE_ATTR_2(temp4_crit, S_IRUGO | S_IWUSR, show_temp,
413 			    store_temp, 0x3d, 0);
414 
415 static SENSOR_DEVICE_ATTR_2(temp5_input, S_IRUGO, show_temp, NULL, 0x06,
416 			    REG_TEMP_PECI_LSB);
417 static SENSOR_DEVICE_ATTR_2(temp5_min, S_IRUGO | S_IWUSR, show_temp,
418 			    store_temp, 0x39, 0);
419 static SENSOR_DEVICE_ATTR_2(temp5_max, S_IRUGO | S_IWUSR, show_temp,
420 			    store_temp, 0x38, 0);
421 static SENSOR_DEVICE_ATTR_2(temp5_crit, S_IRUGO | S_IWUSR, show_temp,
422 			    store_temp, 0x3e, 0);
423 
424 static SENSOR_DEVICE_ATTR_2(temp6_input, S_IRUGO, show_temp, NULL, 0x07,
425 			    REG_TEMP_PECI_LSB);
426 
427 static SENSOR_DEVICE_ATTR_2(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
428 			    0x18, 0);
429 static SENSOR_DEVICE_ATTR_2(temp2_min_alarm, S_IRUGO, show_alarm, NULL,
430 			    0x18, 1);
431 static SENSOR_DEVICE_ATTR_2(temp3_min_alarm, S_IRUGO, show_alarm, NULL,
432 			    0x18, 2);
433 static SENSOR_DEVICE_ATTR_2(temp4_min_alarm, S_IRUGO, show_alarm, NULL,
434 			    0x18, 3);
435 static SENSOR_DEVICE_ATTR_2(temp5_min_alarm, S_IRUGO, show_alarm, NULL,
436 			    0x18, 4);
437 
438 static SENSOR_DEVICE_ATTR_2(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
439 			    0x19, 0);
440 static SENSOR_DEVICE_ATTR_2(temp2_max_alarm, S_IRUGO, show_alarm, NULL,
441 			    0x19, 1);
442 static SENSOR_DEVICE_ATTR_2(temp3_max_alarm, S_IRUGO, show_alarm, NULL,
443 			    0x19, 2);
444 static SENSOR_DEVICE_ATTR_2(temp4_max_alarm, S_IRUGO, show_alarm, NULL,
445 			    0x19, 3);
446 static SENSOR_DEVICE_ATTR_2(temp5_max_alarm, S_IRUGO, show_alarm, NULL,
447 			    0x19, 4);
448 
449 static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
450 			    0x1b, 0);
451 static SENSOR_DEVICE_ATTR_2(temp2_crit_alarm, S_IRUGO, show_alarm, NULL,
452 			    0x1b, 1);
453 static SENSOR_DEVICE_ATTR_2(temp3_crit_alarm, S_IRUGO, show_alarm, NULL,
454 			    0x1b, 2);
455 static SENSOR_DEVICE_ATTR_2(temp4_crit_alarm, S_IRUGO, show_alarm, NULL,
456 			    0x1b, 3);
457 static SENSOR_DEVICE_ATTR_2(temp5_crit_alarm, S_IRUGO, show_alarm, NULL,
458 			    0x1b, 4);
459 
460 static SENSOR_DEVICE_ATTR_2(temp1_fault, S_IRUGO, show_alarm, NULL, 0x17, 0);
461 static SENSOR_DEVICE_ATTR_2(temp2_fault, S_IRUGO, show_alarm, NULL, 0x17, 1);
462 static SENSOR_DEVICE_ATTR_2(temp3_fault, S_IRUGO, show_alarm, NULL, 0x17, 2);
463 
464 static SENSOR_DEVICE_ATTR_2(temp1_beep, S_IRUGO | S_IWUSR, show_beep,
465 			    store_beep, 0x5c, 0);
466 static SENSOR_DEVICE_ATTR_2(temp2_beep, S_IRUGO | S_IWUSR, show_beep,
467 			    store_beep, 0x5c, 1);
468 static SENSOR_DEVICE_ATTR_2(temp3_beep, S_IRUGO | S_IWUSR, show_beep,
469 			    store_beep, 0x5c, 2);
470 static SENSOR_DEVICE_ATTR_2(temp4_beep, S_IRUGO | S_IWUSR, show_beep,
471 			    store_beep, 0x5c, 3);
472 static SENSOR_DEVICE_ATTR_2(temp5_beep, S_IRUGO | S_IWUSR, show_beep,
473 			    store_beep, 0x5c, 4);
474 static SENSOR_DEVICE_ATTR_2(temp6_beep, S_IRUGO | S_IWUSR, show_beep,
475 			    store_beep, 0x5c, 5);
476 
477 static struct attribute *nct7802_temp_attrs[] = {
478 	&sensor_dev_attr_temp1_input.dev_attr.attr,
479 	&sensor_dev_attr_temp1_min.dev_attr.attr,
480 	&sensor_dev_attr_temp1_max.dev_attr.attr,
481 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
482 	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
483 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
484 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
485 	&sensor_dev_attr_temp1_fault.dev_attr.attr,
486 	&sensor_dev_attr_temp1_beep.dev_attr.attr,
487 
488 	&sensor_dev_attr_temp2_input.dev_attr.attr,		/* 9 */
489 	&sensor_dev_attr_temp2_min.dev_attr.attr,
490 	&sensor_dev_attr_temp2_max.dev_attr.attr,
491 	&sensor_dev_attr_temp2_crit.dev_attr.attr,
492 	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
493 	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
494 	&sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
495 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
496 	&sensor_dev_attr_temp2_beep.dev_attr.attr,
497 
498 	&sensor_dev_attr_temp3_input.dev_attr.attr,		/* 18 */
499 	&sensor_dev_attr_temp3_min.dev_attr.attr,
500 	&sensor_dev_attr_temp3_max.dev_attr.attr,
501 	&sensor_dev_attr_temp3_crit.dev_attr.attr,
502 	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
503 	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
504 	&sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
505 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
506 	&sensor_dev_attr_temp3_beep.dev_attr.attr,
507 
508 	&sensor_dev_attr_temp4_input.dev_attr.attr,		/* 27 */
509 	&sensor_dev_attr_temp4_min.dev_attr.attr,
510 	&sensor_dev_attr_temp4_max.dev_attr.attr,
511 	&sensor_dev_attr_temp4_crit.dev_attr.attr,
512 	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
513 	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
514 	&sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
515 	&sensor_dev_attr_temp4_beep.dev_attr.attr,
516 
517 	&sensor_dev_attr_temp5_input.dev_attr.attr,		/* 35 */
518 	&sensor_dev_attr_temp5_min.dev_attr.attr,
519 	&sensor_dev_attr_temp5_max.dev_attr.attr,
520 	&sensor_dev_attr_temp5_crit.dev_attr.attr,
521 	&sensor_dev_attr_temp5_min_alarm.dev_attr.attr,
522 	&sensor_dev_attr_temp5_max_alarm.dev_attr.attr,
523 	&sensor_dev_attr_temp5_crit_alarm.dev_attr.attr,
524 	&sensor_dev_attr_temp5_beep.dev_attr.attr,
525 
526 	&sensor_dev_attr_temp6_input.dev_attr.attr,		/* 43 */
527 	&sensor_dev_attr_temp6_beep.dev_attr.attr,
528 
529 	NULL
530 };
531 
532 static umode_t nct7802_temp_is_visible(struct kobject *kobj,
533 				       struct attribute *attr, int index)
534 {
535 	struct device *dev = container_of(kobj, struct device, kobj);
536 	struct nct7802_data *data = dev_get_drvdata(dev);
537 	unsigned int reg;
538 	int err;
539 
540 	err = regmap_read(data->regmap, REG_MODE, &reg);
541 	if (err < 0)
542 		return 0;
543 
544 	if (index < 9 &&
545 	    (reg & 03) != 0x01 && (reg & 0x03) != 0x02)		/* RD1 */
546 		return 0;
547 	if (index >= 9 && index < 18 &&
548 	    (reg & 0x0c) != 0x04 && (reg & 0x0c) != 0x08)	/* RD2 */
549 		return 0;
550 	if (index >= 18 && index < 27 && (reg & 0x30) != 0x10)	/* RD3 */
551 		return 0;
552 	if (index >= 27 && index < 35)				/* local */
553 		return attr->mode;
554 
555 	err = regmap_read(data->regmap, REG_PECI_ENABLE, &reg);
556 	if (err < 0)
557 		return 0;
558 
559 	if (index >= 35 && index < 43 && !(reg & 0x01))		/* PECI 0 */
560 		return 0;
561 
562 	if (index >= 0x43 && (!(reg & 0x02)))			/* PECI 1 */
563 		return 0;
564 
565 	return attr->mode;
566 }
567 
568 static struct attribute_group nct7802_temp_group = {
569 	.attrs = nct7802_temp_attrs,
570 	.is_visible = nct7802_temp_is_visible,
571 };
572 
573 static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO, show_in, NULL, 0, 0);
574 static SENSOR_DEVICE_ATTR_2(in0_min, S_IRUGO | S_IWUSR, show_in, store_in,
575 			    0, 1);
576 static SENSOR_DEVICE_ATTR_2(in0_max, S_IRUGO | S_IWUSR, show_in, store_in,
577 			    0, 2);
578 static SENSOR_DEVICE_ATTR_2(in0_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 3);
579 static SENSOR_DEVICE_ATTR_2(in0_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
580 			    0x5a, 3);
581 
582 static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO, show_in, NULL, 1, 0);
583 
584 static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO, show_in, NULL, 2, 0);
585 static SENSOR_DEVICE_ATTR_2(in2_min, S_IRUGO | S_IWUSR, show_in, store_in,
586 			    2, 1);
587 static SENSOR_DEVICE_ATTR_2(in2_max, S_IRUGO | S_IWUSR, show_in, store_in,
588 			    2, 2);
589 static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 0);
590 static SENSOR_DEVICE_ATTR_2(in2_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
591 			    0x5a, 0);
592 
593 static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO, show_in, NULL, 3, 0);
594 static SENSOR_DEVICE_ATTR_2(in3_min, S_IRUGO | S_IWUSR, show_in, store_in,
595 			    3, 1);
596 static SENSOR_DEVICE_ATTR_2(in3_max, S_IRUGO | S_IWUSR, show_in, store_in,
597 			    3, 2);
598 static SENSOR_DEVICE_ATTR_2(in3_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 1);
599 static SENSOR_DEVICE_ATTR_2(in3_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
600 			    0x5a, 1);
601 
602 static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO, show_in, NULL, 4, 0);
603 static SENSOR_DEVICE_ATTR_2(in4_min, S_IRUGO | S_IWUSR, show_in, store_in,
604 			    4, 1);
605 static SENSOR_DEVICE_ATTR_2(in4_max, S_IRUGO | S_IWUSR, show_in, store_in,
606 			    4, 2);
607 static SENSOR_DEVICE_ATTR_2(in4_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 2);
608 static SENSOR_DEVICE_ATTR_2(in4_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
609 			    0x5a, 2);
610 
611 static struct attribute *nct7802_in_attrs[] = {
612 	&sensor_dev_attr_in0_input.dev_attr.attr,
613 	&sensor_dev_attr_in0_min.dev_attr.attr,
614 	&sensor_dev_attr_in0_max.dev_attr.attr,
615 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
616 	&sensor_dev_attr_in0_beep.dev_attr.attr,
617 
618 	&sensor_dev_attr_in1_input.dev_attr.attr,	/* 5 */
619 
620 	&sensor_dev_attr_in2_input.dev_attr.attr,	/* 6 */
621 	&sensor_dev_attr_in2_min.dev_attr.attr,
622 	&sensor_dev_attr_in2_max.dev_attr.attr,
623 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
624 	&sensor_dev_attr_in2_beep.dev_attr.attr,
625 
626 	&sensor_dev_attr_in3_input.dev_attr.attr,	/* 11 */
627 	&sensor_dev_attr_in3_min.dev_attr.attr,
628 	&sensor_dev_attr_in3_max.dev_attr.attr,
629 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
630 	&sensor_dev_attr_in3_beep.dev_attr.attr,
631 
632 	&sensor_dev_attr_in4_input.dev_attr.attr,	/* 17 */
633 	&sensor_dev_attr_in4_min.dev_attr.attr,
634 	&sensor_dev_attr_in4_max.dev_attr.attr,
635 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
636 	&sensor_dev_attr_in4_beep.dev_attr.attr,
637 
638 	NULL,
639 };
640 
641 static umode_t nct7802_in_is_visible(struct kobject *kobj,
642 				     struct attribute *attr, int index)
643 {
644 	struct device *dev = container_of(kobj, struct device, kobj);
645 	struct nct7802_data *data = dev_get_drvdata(dev);
646 	unsigned int reg;
647 	int err;
648 
649 	if (index < 6)						/* VCC, VCORE */
650 		return attr->mode;
651 
652 	err = regmap_read(data->regmap, REG_MODE, &reg);
653 	if (err < 0)
654 		return 0;
655 
656 	if (index >= 6 && index < 11 && (reg & 0x03) != 0x03)	/* VSEN1 */
657 		return 0;
658 	if (index >= 11 && index < 17 && (reg & 0x0c) != 0x0c)	/* VSEN2 */
659 		return 0;
660 	if (index >= 17 && (reg & 0x30) != 0x30)		/* VSEN3 */
661 		return 0;
662 
663 	return attr->mode;
664 }
665 
666 static struct attribute_group nct7802_in_group = {
667 	.attrs = nct7802_in_attrs,
668 	.is_visible = nct7802_in_is_visible,
669 };
670 
671 static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0x10);
672 static SENSOR_DEVICE_ATTR_2(fan1_min, S_IRUGO | S_IWUSR, show_fan_min,
673 			    store_fan_min, 0x49, 0x4c);
674 static SENSOR_DEVICE_ATTR_2(fan1_alarm, S_IRUGO, show_alarm, NULL, 0x1a, 0);
675 static SENSOR_DEVICE_ATTR_2(fan1_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
676 			    0x5b, 0);
677 static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 0x11);
678 static SENSOR_DEVICE_ATTR_2(fan2_min, S_IRUGO | S_IWUSR, show_fan_min,
679 			    store_fan_min, 0x4a, 0x4d);
680 static SENSOR_DEVICE_ATTR_2(fan2_alarm, S_IRUGO, show_alarm, NULL, 0x1a, 1);
681 static SENSOR_DEVICE_ATTR_2(fan2_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
682 			    0x5b, 1);
683 static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan, NULL, 0x12);
684 static SENSOR_DEVICE_ATTR_2(fan3_min, S_IRUGO | S_IWUSR, show_fan_min,
685 			    store_fan_min, 0x4b, 0x4e);
686 static SENSOR_DEVICE_ATTR_2(fan3_alarm, S_IRUGO, show_alarm, NULL, 0x1a, 2);
687 static SENSOR_DEVICE_ATTR_2(fan3_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
688 			    0x5b, 2);
689 
690 static struct attribute *nct7802_fan_attrs[] = {
691 	&sensor_dev_attr_fan1_input.dev_attr.attr,
692 	&sensor_dev_attr_fan1_min.dev_attr.attr,
693 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
694 	&sensor_dev_attr_fan1_beep.dev_attr.attr,
695 	&sensor_dev_attr_fan2_input.dev_attr.attr,
696 	&sensor_dev_attr_fan2_min.dev_attr.attr,
697 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
698 	&sensor_dev_attr_fan2_beep.dev_attr.attr,
699 	&sensor_dev_attr_fan3_input.dev_attr.attr,
700 	&sensor_dev_attr_fan3_min.dev_attr.attr,
701 	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
702 	&sensor_dev_attr_fan3_beep.dev_attr.attr,
703 
704 	NULL
705 };
706 
707 static umode_t nct7802_fan_is_visible(struct kobject *kobj,
708 				      struct attribute *attr, int index)
709 {
710 	struct device *dev = container_of(kobj, struct device, kobj);
711 	struct nct7802_data *data = dev_get_drvdata(dev);
712 	int fan = index / 4;	/* 4 attributes per fan */
713 	unsigned int reg;
714 	int err;
715 
716 	err = regmap_read(data->regmap, REG_FAN_ENABLE, &reg);
717 	if (err < 0 || !(reg & (1 << fan)))
718 		return 0;
719 
720 	return attr->mode;
721 }
722 
723 static struct attribute_group nct7802_fan_group = {
724 	.attrs = nct7802_fan_attrs,
725 	.is_visible = nct7802_fan_is_visible,
726 };
727 
728 static const struct attribute_group *nct7802_groups[] = {
729 	&nct7802_temp_group,
730 	&nct7802_in_group,
731 	&nct7802_fan_group,
732 	NULL
733 };
734 
735 static int nct7802_detect(struct i2c_client *client,
736 			  struct i2c_board_info *info)
737 {
738 	int reg;
739 
740 	/*
741 	 * Chip identification registers are only available in bank 0,
742 	 * so only attempt chip detection if bank 0 is selected
743 	 */
744 	reg = i2c_smbus_read_byte_data(client, REG_BANK);
745 	if (reg != 0x00)
746 		return -ENODEV;
747 
748 	reg = i2c_smbus_read_byte_data(client, REG_VENDOR_ID);
749 	if (reg != 0x50)
750 		return -ENODEV;
751 
752 	reg = i2c_smbus_read_byte_data(client, REG_CHIP_ID);
753 	if (reg != 0xc3)
754 		return -ENODEV;
755 
756 	reg = i2c_smbus_read_byte_data(client, REG_VERSION_ID);
757 	if (reg < 0 || (reg & 0xf0) != 0x20)
758 		return -ENODEV;
759 
760 	/* Also validate lower bits of voltage and temperature registers */
761 	reg = i2c_smbus_read_byte_data(client, REG_TEMP_LSB);
762 	if (reg < 0 || (reg & 0x1f))
763 		return -ENODEV;
764 
765 	reg = i2c_smbus_read_byte_data(client, REG_TEMP_PECI_LSB);
766 	if (reg < 0 || (reg & 0x3f))
767 		return -ENODEV;
768 
769 	reg = i2c_smbus_read_byte_data(client, REG_VOLTAGE_LOW);
770 	if (reg < 0 || (reg & 0x3f))
771 		return -ENODEV;
772 
773 	strlcpy(info->type, "nct7802", I2C_NAME_SIZE);
774 	return 0;
775 }
776 
777 static bool nct7802_regmap_is_volatile(struct device *dev, unsigned int reg)
778 {
779 	return reg != REG_BANK && reg <= 0x20;
780 }
781 
782 static struct regmap_config nct7802_regmap_config = {
783 	.reg_bits = 8,
784 	.val_bits = 8,
785 	.cache_type = REGCACHE_RBTREE,
786 	.volatile_reg = nct7802_regmap_is_volatile,
787 };
788 
789 static int nct7802_init_chip(struct nct7802_data *data)
790 {
791 	int err;
792 
793 	/* Enable ADC */
794 	err = regmap_update_bits(data->regmap, REG_START, 0x01, 0x01);
795 	if (err)
796 		return err;
797 
798 	/* Enable local temperature sensor */
799 	err = regmap_update_bits(data->regmap, REG_MODE, 0x40, 0x40);
800 	if (err)
801 		return err;
802 
803 	/* Enable Vcore and VCC voltage monitoring */
804 	return regmap_update_bits(data->regmap, REG_VMON_ENABLE, 0x03, 0x03);
805 }
806 
807 static int nct7802_probe(struct i2c_client *client,
808 			 const struct i2c_device_id *id)
809 {
810 	struct device *dev = &client->dev;
811 	struct nct7802_data *data;
812 	struct device *hwmon_dev;
813 	int ret;
814 
815 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
816 	if (data == NULL)
817 		return -ENOMEM;
818 
819 	data->regmap = devm_regmap_init_i2c(client, &nct7802_regmap_config);
820 	if (IS_ERR(data->regmap))
821 		return PTR_ERR(data->regmap);
822 
823 	mutex_init(&data->access_lock);
824 
825 	ret = nct7802_init_chip(data);
826 	if (ret < 0)
827 		return ret;
828 
829 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
830 							   data,
831 							   nct7802_groups);
832 	return PTR_ERR_OR_ZERO(hwmon_dev);
833 }
834 
835 static const unsigned short nct7802_address_list[] = {
836 	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END
837 };
838 
839 static const struct i2c_device_id nct7802_idtable[] = {
840 	{ "nct7802", 0 },
841 	{ }
842 };
843 MODULE_DEVICE_TABLE(i2c, nct7802_idtable);
844 
845 static struct i2c_driver nct7802_driver = {
846 	.class = I2C_CLASS_HWMON,
847 	.driver = {
848 		.name = DRVNAME,
849 	},
850 	.detect = nct7802_detect,
851 	.probe = nct7802_probe,
852 	.id_table = nct7802_idtable,
853 	.address_list = nct7802_address_list,
854 };
855 
856 module_i2c_driver(nct7802_driver);
857 
858 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
859 MODULE_DESCRIPTION("NCT7802Y Hardware Monitoring Driver");
860 MODULE_LICENSE("GPL v2");
861