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
32static const u8 REG_VOLTAGE[5] = { 0x09, 0x0a, 0x0c, 0x0d, 0x0e };
33
34static const u8 REG_VOLTAGE_LIMIT_LSB[2][5] = {
35	{ 0x40, 0x00, 0x42, 0x44, 0x46 },
36	{ 0x3f, 0x00, 0x41, 0x43, 0x45 },
37};
38
39static const u8 REG_VOLTAGE_LIMIT_MSB[5] = { 0x48, 0x00, 0x47, 0x47, 0x48 };
40
41static 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
64struct nct7802_data {
65	struct regmap *regmap;
66	struct mutex access_lock; /* for multi-byte read and write operations */
67};
68
69static 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;
89abort:
90	mutex_unlock(&data->access_lock);
91	return err;
92}
93
94static 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);
112abort:
113	mutex_unlock(&data->access_lock);
114	return ret;
115}
116
117static 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);
136abort:
137	mutex_unlock(&data->access_lock);
138	return ret;
139}
140
141static 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);
158abort:
159	mutex_unlock(&data->access_lock);
160	return err;
161}
162
163static u8 nct7802_vmul[] = { 4, 2, 2, 2, 2 };
164
165static 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	}
192abort:
193	mutex_unlock(&data->access_lock);
194	return ret;
195}
196
197static int nct7802_write_voltage(struct nct7802_data *data, int nr, int index,
198				 unsigned long 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);
215abort:
216	mutex_unlock(&data->access_lock);
217	return err;
218}
219
220static 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
234static 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
252static 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
266static 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
285static 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
299static 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
313static 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
329static 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
345static ssize_t
346show_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
360static ssize_t
361store_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
380static SENSOR_DEVICE_ATTR_2(temp1_input, S_IRUGO, show_temp, NULL, 0x01,
381			    REG_TEMP_LSB);
382static SENSOR_DEVICE_ATTR_2(temp1_min, S_IRUGO | S_IWUSR, show_temp,
383			    store_temp, 0x31, 0);
384static SENSOR_DEVICE_ATTR_2(temp1_max, S_IRUGO | S_IWUSR, show_temp,
385			    store_temp, 0x30, 0);
386static SENSOR_DEVICE_ATTR_2(temp1_crit, S_IRUGO | S_IWUSR, show_temp,
387			    store_temp, 0x3a, 0);
388
389static SENSOR_DEVICE_ATTR_2(temp2_input, S_IRUGO, show_temp, NULL, 0x02,
390			    REG_TEMP_LSB);
391static SENSOR_DEVICE_ATTR_2(temp2_min, S_IRUGO | S_IWUSR, show_temp,
392			    store_temp, 0x33, 0);
393static SENSOR_DEVICE_ATTR_2(temp2_max, S_IRUGO | S_IWUSR, show_temp,
394			    store_temp, 0x32, 0);
395static SENSOR_DEVICE_ATTR_2(temp2_crit, S_IRUGO | S_IWUSR, show_temp,
396			    store_temp, 0x3b, 0);
397
398static SENSOR_DEVICE_ATTR_2(temp3_input, S_IRUGO, show_temp, NULL, 0x03,
399			    REG_TEMP_LSB);
400static SENSOR_DEVICE_ATTR_2(temp3_min, S_IRUGO | S_IWUSR, show_temp,
401			    store_temp, 0x35, 0);
402static SENSOR_DEVICE_ATTR_2(temp3_max, S_IRUGO | S_IWUSR, show_temp,
403			    store_temp, 0x34, 0);
404static SENSOR_DEVICE_ATTR_2(temp3_crit, S_IRUGO | S_IWUSR, show_temp,
405			    store_temp, 0x3c, 0);
406
407static SENSOR_DEVICE_ATTR_2(temp4_input, S_IRUGO, show_temp, NULL, 0x04, 0);
408static SENSOR_DEVICE_ATTR_2(temp4_min, S_IRUGO | S_IWUSR, show_temp,
409			    store_temp, 0x37, 0);
410static SENSOR_DEVICE_ATTR_2(temp4_max, S_IRUGO | S_IWUSR, show_temp,
411			    store_temp, 0x36, 0);
412static SENSOR_DEVICE_ATTR_2(temp4_crit, S_IRUGO | S_IWUSR, show_temp,
413			    store_temp, 0x3d, 0);
414
415static SENSOR_DEVICE_ATTR_2(temp5_input, S_IRUGO, show_temp, NULL, 0x06,
416			    REG_TEMP_PECI_LSB);
417static SENSOR_DEVICE_ATTR_2(temp5_min, S_IRUGO | S_IWUSR, show_temp,
418			    store_temp, 0x39, 0);
419static SENSOR_DEVICE_ATTR_2(temp5_max, S_IRUGO | S_IWUSR, show_temp,
420			    store_temp, 0x38, 0);
421static SENSOR_DEVICE_ATTR_2(temp5_crit, S_IRUGO | S_IWUSR, show_temp,
422			    store_temp, 0x3e, 0);
423
424static SENSOR_DEVICE_ATTR_2(temp6_input, S_IRUGO, show_temp, NULL, 0x07,
425			    REG_TEMP_PECI_LSB);
426
427static SENSOR_DEVICE_ATTR_2(temp1_min_alarm, S_IRUGO, show_alarm, NULL,
428			    0x18, 0);
429static SENSOR_DEVICE_ATTR_2(temp2_min_alarm, S_IRUGO, show_alarm, NULL,
430			    0x18, 1);
431static SENSOR_DEVICE_ATTR_2(temp3_min_alarm, S_IRUGO, show_alarm, NULL,
432			    0x18, 2);
433static SENSOR_DEVICE_ATTR_2(temp4_min_alarm, S_IRUGO, show_alarm, NULL,
434			    0x18, 3);
435static SENSOR_DEVICE_ATTR_2(temp5_min_alarm, S_IRUGO, show_alarm, NULL,
436			    0x18, 4);
437
438static SENSOR_DEVICE_ATTR_2(temp1_max_alarm, S_IRUGO, show_alarm, NULL,
439			    0x19, 0);
440static SENSOR_DEVICE_ATTR_2(temp2_max_alarm, S_IRUGO, show_alarm, NULL,
441			    0x19, 1);
442static SENSOR_DEVICE_ATTR_2(temp3_max_alarm, S_IRUGO, show_alarm, NULL,
443			    0x19, 2);
444static SENSOR_DEVICE_ATTR_2(temp4_max_alarm, S_IRUGO, show_alarm, NULL,
445			    0x19, 3);
446static SENSOR_DEVICE_ATTR_2(temp5_max_alarm, S_IRUGO, show_alarm, NULL,
447			    0x19, 4);
448
449static SENSOR_DEVICE_ATTR_2(temp1_crit_alarm, S_IRUGO, show_alarm, NULL,
450			    0x1b, 0);
451static SENSOR_DEVICE_ATTR_2(temp2_crit_alarm, S_IRUGO, show_alarm, NULL,
452			    0x1b, 1);
453static SENSOR_DEVICE_ATTR_2(temp3_crit_alarm, S_IRUGO, show_alarm, NULL,
454			    0x1b, 2);
455static SENSOR_DEVICE_ATTR_2(temp4_crit_alarm, S_IRUGO, show_alarm, NULL,
456			    0x1b, 3);
457static SENSOR_DEVICE_ATTR_2(temp5_crit_alarm, S_IRUGO, show_alarm, NULL,
458			    0x1b, 4);
459
460static SENSOR_DEVICE_ATTR_2(temp1_fault, S_IRUGO, show_alarm, NULL, 0x17, 0);
461static SENSOR_DEVICE_ATTR_2(temp2_fault, S_IRUGO, show_alarm, NULL, 0x17, 1);
462static SENSOR_DEVICE_ATTR_2(temp3_fault, S_IRUGO, show_alarm, NULL, 0x17, 2);
463
464static SENSOR_DEVICE_ATTR_2(temp1_beep, S_IRUGO | S_IWUSR, show_beep,
465			    store_beep, 0x5c, 0);
466static SENSOR_DEVICE_ATTR_2(temp2_beep, S_IRUGO | S_IWUSR, show_beep,
467			    store_beep, 0x5c, 1);
468static SENSOR_DEVICE_ATTR_2(temp3_beep, S_IRUGO | S_IWUSR, show_beep,
469			    store_beep, 0x5c, 2);
470static SENSOR_DEVICE_ATTR_2(temp4_beep, S_IRUGO | S_IWUSR, show_beep,
471			    store_beep, 0x5c, 3);
472static SENSOR_DEVICE_ATTR_2(temp5_beep, S_IRUGO | S_IWUSR, show_beep,
473			    store_beep, 0x5c, 4);
474static SENSOR_DEVICE_ATTR_2(temp6_beep, S_IRUGO | S_IWUSR, show_beep,
475			    store_beep, 0x5c, 5);
476
477static 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
532static 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) != 0x20)	/* 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
568static struct attribute_group nct7802_temp_group = {
569	.attrs = nct7802_temp_attrs,
570	.is_visible = nct7802_temp_is_visible,
571};
572
573static SENSOR_DEVICE_ATTR_2(in0_input, S_IRUGO, show_in, NULL, 0, 0);
574static SENSOR_DEVICE_ATTR_2(in0_min, S_IRUGO | S_IWUSR, show_in, store_in,
575			    0, 1);
576static SENSOR_DEVICE_ATTR_2(in0_max, S_IRUGO | S_IWUSR, show_in, store_in,
577			    0, 2);
578static SENSOR_DEVICE_ATTR_2(in0_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 3);
579static SENSOR_DEVICE_ATTR_2(in0_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
580			    0x5a, 3);
581
582static SENSOR_DEVICE_ATTR_2(in1_input, S_IRUGO, show_in, NULL, 1, 0);
583
584static SENSOR_DEVICE_ATTR_2(in2_input, S_IRUGO, show_in, NULL, 2, 0);
585static SENSOR_DEVICE_ATTR_2(in2_min, S_IRUGO | S_IWUSR, show_in, store_in,
586			    2, 1);
587static SENSOR_DEVICE_ATTR_2(in2_max, S_IRUGO | S_IWUSR, show_in, store_in,
588			    2, 2);
589static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 0);
590static SENSOR_DEVICE_ATTR_2(in2_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
591			    0x5a, 0);
592
593static SENSOR_DEVICE_ATTR_2(in3_input, S_IRUGO, show_in, NULL, 3, 0);
594static SENSOR_DEVICE_ATTR_2(in3_min, S_IRUGO | S_IWUSR, show_in, store_in,
595			    3, 1);
596static SENSOR_DEVICE_ATTR_2(in3_max, S_IRUGO | S_IWUSR, show_in, store_in,
597			    3, 2);
598static SENSOR_DEVICE_ATTR_2(in3_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 1);
599static SENSOR_DEVICE_ATTR_2(in3_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
600			    0x5a, 1);
601
602static SENSOR_DEVICE_ATTR_2(in4_input, S_IRUGO, show_in, NULL, 4, 0);
603static SENSOR_DEVICE_ATTR_2(in4_min, S_IRUGO | S_IWUSR, show_in, store_in,
604			    4, 1);
605static SENSOR_DEVICE_ATTR_2(in4_max, S_IRUGO | S_IWUSR, show_in, store_in,
606			    4, 2);
607static SENSOR_DEVICE_ATTR_2(in4_alarm, S_IRUGO, show_alarm, NULL, 0x1e, 2);
608static SENSOR_DEVICE_ATTR_2(in4_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
609			    0x5a, 2);
610
611static 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
641static 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
666static struct attribute_group nct7802_in_group = {
667	.attrs = nct7802_in_attrs,
668	.is_visible = nct7802_in_is_visible,
669};
670
671static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan, NULL, 0x10);
672static SENSOR_DEVICE_ATTR_2(fan1_min, S_IRUGO | S_IWUSR, show_fan_min,
673			    store_fan_min, 0x49, 0x4c);
674static SENSOR_DEVICE_ATTR_2(fan1_alarm, S_IRUGO, show_alarm, NULL, 0x1a, 0);
675static SENSOR_DEVICE_ATTR_2(fan1_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
676			    0x5b, 0);
677static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan, NULL, 0x11);
678static SENSOR_DEVICE_ATTR_2(fan2_min, S_IRUGO | S_IWUSR, show_fan_min,
679			    store_fan_min, 0x4a, 0x4d);
680static SENSOR_DEVICE_ATTR_2(fan2_alarm, S_IRUGO, show_alarm, NULL, 0x1a, 1);
681static SENSOR_DEVICE_ATTR_2(fan2_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
682			    0x5b, 1);
683static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, show_fan, NULL, 0x12);
684static SENSOR_DEVICE_ATTR_2(fan3_min, S_IRUGO | S_IWUSR, show_fan_min,
685			    store_fan_min, 0x4b, 0x4e);
686static SENSOR_DEVICE_ATTR_2(fan3_alarm, S_IRUGO, show_alarm, NULL, 0x1a, 2);
687static SENSOR_DEVICE_ATTR_2(fan3_beep, S_IRUGO | S_IWUSR, show_beep, store_beep,
688			    0x5b, 2);
689
690static 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
707static 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
723static struct attribute_group nct7802_fan_group = {
724	.attrs = nct7802_fan_attrs,
725	.is_visible = nct7802_fan_is_visible,
726};
727
728static const struct attribute_group *nct7802_groups[] = {
729	&nct7802_temp_group,
730	&nct7802_in_group,
731	&nct7802_fan_group,
732	NULL
733};
734
735static 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
777static bool nct7802_regmap_is_volatile(struct device *dev, unsigned int reg)
778{
779	return reg != REG_BANK && reg <= 0x20;
780}
781
782static const 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
789static 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
807static 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
835static const unsigned short nct7802_address_list[] = {
836	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END
837};
838
839static const struct i2c_device_id nct7802_idtable[] = {
840	{ "nct7802", 0 },
841	{ }
842};
843MODULE_DEVICE_TABLE(i2c, nct7802_idtable);
844
845static 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
856module_i2c_driver(nct7802_driver);
857
858MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
859MODULE_DESCRIPTION("NCT7802Y Hardware Monitoring Driver");
860MODULE_LICENSE("GPL v2");
861