xref: /linux/drivers/hwmon/lm87.c (revision b1a54551dd9ed5ef1763b97b35a0999ca002b95c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * lm87.c
4  *
5  * Copyright (C) 2000       Frodo Looijaard <frodol@dds.nl>
6  *                          Philip Edelbrock <phil@netroedge.com>
7  *                          Stephen Rousset <stephen.rousset@rocketlogix.com>
8  *                          Dan Eaton <dan.eaton@rocketlogix.com>
9  * Copyright (C) 2004-2008  Jean Delvare <jdelvare@suse.de>
10  *
11  * Original port to Linux 2.6 by Jeff Oliver.
12  *
13  * The LM87 is a sensor chip made by National Semiconductor. It monitors up
14  * to 8 voltages (including its own power source), up to three temperatures
15  * (its own plus up to two external ones) and up to two fans. The default
16  * configuration is 6 voltages, two temperatures and two fans (see below).
17  * Voltages are scaled internally with ratios such that the nominal value of
18  * each voltage correspond to a register value of 192 (which means a
19  * resolution of about 0.5% of the nominal value). Temperature values are
20  * reported with a 1 deg resolution and a 3-4 deg accuracy. Complete
21  * datasheet can be obtained from National's website at:
22  *   http://www.national.com/pf/LM/LM87.html
23  *
24  * Some functions share pins, so not all functions are available at the same
25  * time. Which are depends on the hardware setup. This driver normally
26  * assumes that firmware configured the chip correctly. Where this is not
27  * the case, platform code must set the I2C client's platform_data to point
28  * to a u8 value to be written to the channel register.
29  * For reference, here is the list of exclusive functions:
30  *  - in0+in5 (default) or temp3
31  *  - fan1 (default) or in6
32  *  - fan2 (default) or in7
33  *  - VID lines (default) or IRQ lines (not handled by this driver)
34  *
35  * The LM87 additionally features an analog output, supposedly usable to
36  * control the speed of a fan. All new chips use pulse width modulation
37  * instead. The LM87 is the only hardware monitoring chipset I know of
38  * which uses amplitude modulation. Be careful when using this feature.
39  *
40  * This driver also supports the ADM1024, a sensor chip made by Analog
41  * Devices. That chip is fully compatible with the LM87. Complete
42  * datasheet can be obtained from Analog's website at:
43  *   https://www.analog.com/en/prod/0,2877,ADM1024,00.html
44  */
45 
46 #include <linux/module.h>
47 #include <linux/init.h>
48 #include <linux/slab.h>
49 #include <linux/jiffies.h>
50 #include <linux/i2c.h>
51 #include <linux/hwmon.h>
52 #include <linux/hwmon-sysfs.h>
53 #include <linux/hwmon-vid.h>
54 #include <linux/err.h>
55 #include <linux/mutex.h>
56 #include <linux/regulator/consumer.h>
57 
58 /*
59  * Addresses to scan
60  * LM87 has three possible addresses: 0x2c, 0x2d and 0x2e.
61  */
62 
63 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };
64 
65 /*
66  * The LM87 registers
67  */
68 
69 /* nr in 0..5 */
70 #define LM87_REG_IN(nr)			(0x20 + (nr))
71 #define LM87_REG_IN_MAX(nr)		(0x2B + (nr) * 2)
72 #define LM87_REG_IN_MIN(nr)		(0x2C + (nr) * 2)
73 /* nr in 0..1 */
74 #define LM87_REG_AIN(nr)		(0x28 + (nr))
75 #define LM87_REG_AIN_MIN(nr)		(0x1A + (nr))
76 #define LM87_REG_AIN_MAX(nr)		(0x3B + (nr))
77 
78 static u8 LM87_REG_TEMP[3] = { 0x27, 0x26, 0x20 };
79 static u8 LM87_REG_TEMP_HIGH[3] = { 0x39, 0x37, 0x2B };
80 static u8 LM87_REG_TEMP_LOW[3] = { 0x3A, 0x38, 0x2C };
81 
82 #define LM87_REG_TEMP_HW_INT_LOCK	0x13
83 #define LM87_REG_TEMP_HW_EXT_LOCK	0x14
84 #define LM87_REG_TEMP_HW_INT		0x17
85 #define LM87_REG_TEMP_HW_EXT		0x18
86 
87 /* nr in 0..1 */
88 #define LM87_REG_FAN(nr)		(0x28 + (nr))
89 #define LM87_REG_FAN_MIN(nr)		(0x3B + (nr))
90 #define LM87_REG_AOUT			0x19
91 
92 #define LM87_REG_CONFIG			0x40
93 #define LM87_REG_CHANNEL_MODE		0x16
94 #define LM87_REG_VID_FAN_DIV		0x47
95 #define LM87_REG_VID4			0x49
96 
97 #define LM87_REG_ALARMS1		0x41
98 #define LM87_REG_ALARMS2		0x42
99 
100 #define LM87_REG_COMPANY_ID		0x3E
101 #define LM87_REG_REVISION		0x3F
102 
103 /*
104  * Conversions and various macros
105  * The LM87 uses signed 8-bit values for temperatures.
106  */
107 
108 #define IN_FROM_REG(reg, scale)	(((reg) * (scale) + 96) / 192)
109 #define IN_TO_REG(val, scale)	((val) <= 0 ? 0 : \
110 				 (val) >= (scale) * 255 / 192 ? 255 : \
111 				 ((val) * 192 + (scale) / 2) / (scale))
112 
113 #define TEMP_FROM_REG(reg)	((reg) * 1000)
114 #define TEMP_TO_REG(val)	((val) <= -127500 ? -128 : \
115 				 (val) >= 126500 ? 127 : \
116 				 (((val) < 0 ? (val) - 500 : \
117 				   (val) + 500) / 1000))
118 
119 #define FAN_FROM_REG(reg, div)	((reg) == 255 || (reg) == 0 ? 0 : \
120 				 (1350000 + (reg)*(div) / 2) / ((reg) * (div)))
121 #define FAN_TO_REG(val, div)	((val) * (div) * 255 <= 1350000 ? 255 : \
122 				 (1350000 + (val)*(div) / 2) / ((val) * (div)))
123 
124 #define FAN_DIV_FROM_REG(reg)	(1 << (reg))
125 
126 /* analog out is 9.80mV/LSB */
127 #define AOUT_FROM_REG(reg)	(((reg) * 98 + 5) / 10)
128 #define AOUT_TO_REG(val)	((val) <= 0 ? 0 : \
129 				 (val) >= 2500 ? 255 : \
130 				 ((val) * 10 + 49) / 98)
131 
132 /* nr in 0..1 */
133 #define CHAN_NO_FAN(nr)		(1 << (nr))
134 #define CHAN_TEMP3		(1 << 2)
135 #define CHAN_VCC_5V		(1 << 3)
136 #define CHAN_NO_VID		(1 << 7)
137 
138 /*
139  * Client data (each client gets its own)
140  */
141 
142 struct lm87_data {
143 	struct mutex update_lock;
144 	bool valid; /* false until following fields are valid */
145 	unsigned long last_updated; /* In jiffies */
146 
147 	u8 channel;		/* register value */
148 	u8 config;		/* original register value */
149 
150 	u8 in[8];		/* register value */
151 	u8 in_max[8];		/* register value */
152 	u8 in_min[8];		/* register value */
153 	u16 in_scale[8];
154 
155 	s8 temp[3];		/* register value */
156 	s8 temp_high[3];	/* register value */
157 	s8 temp_low[3];		/* register value */
158 	s8 temp_crit_int;	/* min of two register values */
159 	s8 temp_crit_ext;	/* min of two register values */
160 
161 	u8 fan[2];		/* register value */
162 	u8 fan_min[2];		/* register value */
163 	u8 fan_div[2];		/* register value, shifted right */
164 	u8 aout;		/* register value */
165 
166 	u16 alarms;		/* register values, combined */
167 	u8 vid;			/* register values, combined */
168 	u8 vrm;
169 
170 	const struct attribute_group *attr_groups[6];
171 };
172 
173 static inline int lm87_read_value(struct i2c_client *client, u8 reg)
174 {
175 	return i2c_smbus_read_byte_data(client, reg);
176 }
177 
178 static inline int lm87_write_value(struct i2c_client *client, u8 reg, u8 value)
179 {
180 	return i2c_smbus_write_byte_data(client, reg, value);
181 }
182 
183 static struct lm87_data *lm87_update_device(struct device *dev)
184 {
185 	struct i2c_client *client = dev_get_drvdata(dev);
186 	struct lm87_data *data = i2c_get_clientdata(client);
187 
188 	mutex_lock(&data->update_lock);
189 
190 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
191 		int i, j;
192 
193 		dev_dbg(&client->dev, "Updating data.\n");
194 
195 		i = (data->channel & CHAN_TEMP3) ? 1 : 0;
196 		j = (data->channel & CHAN_TEMP3) ? 5 : 6;
197 		for (; i < j; i++) {
198 			data->in[i] = lm87_read_value(client,
199 				      LM87_REG_IN(i));
200 			data->in_min[i] = lm87_read_value(client,
201 					  LM87_REG_IN_MIN(i));
202 			data->in_max[i] = lm87_read_value(client,
203 					  LM87_REG_IN_MAX(i));
204 		}
205 
206 		for (i = 0; i < 2; i++) {
207 			if (data->channel & CHAN_NO_FAN(i)) {
208 				data->in[6+i] = lm87_read_value(client,
209 						LM87_REG_AIN(i));
210 				data->in_max[6+i] = lm87_read_value(client,
211 						    LM87_REG_AIN_MAX(i));
212 				data->in_min[6+i] = lm87_read_value(client,
213 						    LM87_REG_AIN_MIN(i));
214 
215 			} else {
216 				data->fan[i] = lm87_read_value(client,
217 					       LM87_REG_FAN(i));
218 				data->fan_min[i] = lm87_read_value(client,
219 						   LM87_REG_FAN_MIN(i));
220 			}
221 		}
222 
223 		j = (data->channel & CHAN_TEMP3) ? 3 : 2;
224 		for (i = 0 ; i < j; i++) {
225 			data->temp[i] = lm87_read_value(client,
226 					LM87_REG_TEMP[i]);
227 			data->temp_high[i] = lm87_read_value(client,
228 					     LM87_REG_TEMP_HIGH[i]);
229 			data->temp_low[i] = lm87_read_value(client,
230 					    LM87_REG_TEMP_LOW[i]);
231 		}
232 
233 		i = lm87_read_value(client, LM87_REG_TEMP_HW_INT_LOCK);
234 		j = lm87_read_value(client, LM87_REG_TEMP_HW_INT);
235 		data->temp_crit_int = min(i, j);
236 
237 		i = lm87_read_value(client, LM87_REG_TEMP_HW_EXT_LOCK);
238 		j = lm87_read_value(client, LM87_REG_TEMP_HW_EXT);
239 		data->temp_crit_ext = min(i, j);
240 
241 		i = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
242 		data->fan_div[0] = (i >> 4) & 0x03;
243 		data->fan_div[1] = (i >> 6) & 0x03;
244 		data->vid = (i & 0x0F)
245 			  | (lm87_read_value(client, LM87_REG_VID4) & 0x01)
246 			     << 4;
247 
248 		data->alarms = lm87_read_value(client, LM87_REG_ALARMS1)
249 			     | (lm87_read_value(client, LM87_REG_ALARMS2)
250 				<< 8);
251 		data->aout = lm87_read_value(client, LM87_REG_AOUT);
252 
253 		data->last_updated = jiffies;
254 		data->valid = true;
255 	}
256 
257 	mutex_unlock(&data->update_lock);
258 
259 	return data;
260 }
261 
262 /*
263  * Sysfs stuff
264  */
265 
266 static ssize_t in_input_show(struct device *dev,
267 			     struct device_attribute *attr, char *buf)
268 {
269 	struct lm87_data *data = lm87_update_device(dev);
270 	int nr = to_sensor_dev_attr(attr)->index;
271 
272 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in[nr],
273 		       data->in_scale[nr]));
274 }
275 
276 static ssize_t in_min_show(struct device *dev, struct device_attribute *attr,
277 			   char *buf)
278 {
279 	struct lm87_data *data = lm87_update_device(dev);
280 	int nr = to_sensor_dev_attr(attr)->index;
281 
282 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_min[nr],
283 		       data->in_scale[nr]));
284 }
285 
286 static ssize_t in_max_show(struct device *dev, struct device_attribute *attr,
287 			   char *buf)
288 {
289 	struct lm87_data *data = lm87_update_device(dev);
290 	int nr = to_sensor_dev_attr(attr)->index;
291 
292 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_max[nr],
293 		       data->in_scale[nr]));
294 }
295 
296 static ssize_t in_min_store(struct device *dev, struct device_attribute *attr,
297 			    const char *buf, size_t count)
298 {
299 	struct i2c_client *client = dev_get_drvdata(dev);
300 	struct lm87_data *data = i2c_get_clientdata(client);
301 	int nr = to_sensor_dev_attr(attr)->index;
302 	long val;
303 	int err;
304 
305 	err = kstrtol(buf, 10, &val);
306 	if (err)
307 		return err;
308 
309 	mutex_lock(&data->update_lock);
310 	data->in_min[nr] = IN_TO_REG(val, data->in_scale[nr]);
311 	lm87_write_value(client, nr < 6 ? LM87_REG_IN_MIN(nr) :
312 			 LM87_REG_AIN_MIN(nr - 6), data->in_min[nr]);
313 	mutex_unlock(&data->update_lock);
314 	return count;
315 }
316 
317 static ssize_t in_max_store(struct device *dev, struct device_attribute *attr,
318 			    const char *buf, size_t count)
319 {
320 	struct i2c_client *client = dev_get_drvdata(dev);
321 	struct lm87_data *data = i2c_get_clientdata(client);
322 	int nr = to_sensor_dev_attr(attr)->index;
323 	long val;
324 	int err;
325 
326 	err = kstrtol(buf, 10, &val);
327 	if (err)
328 		return err;
329 
330 	mutex_lock(&data->update_lock);
331 	data->in_max[nr] = IN_TO_REG(val, data->in_scale[nr]);
332 	lm87_write_value(client, nr < 6 ? LM87_REG_IN_MAX(nr) :
333 			 LM87_REG_AIN_MAX(nr - 6), data->in_max[nr]);
334 	mutex_unlock(&data->update_lock);
335 	return count;
336 }
337 
338 static SENSOR_DEVICE_ATTR_RO(in0_input, in_input, 0);
339 static SENSOR_DEVICE_ATTR_RW(in0_min, in_min, 0);
340 static SENSOR_DEVICE_ATTR_RW(in0_max, in_max, 0);
341 static SENSOR_DEVICE_ATTR_RO(in1_input, in_input, 1);
342 static SENSOR_DEVICE_ATTR_RW(in1_min, in_min, 1);
343 static SENSOR_DEVICE_ATTR_RW(in1_max, in_max, 1);
344 static SENSOR_DEVICE_ATTR_RO(in2_input, in_input, 2);
345 static SENSOR_DEVICE_ATTR_RW(in2_min, in_min, 2);
346 static SENSOR_DEVICE_ATTR_RW(in2_max, in_max, 2);
347 static SENSOR_DEVICE_ATTR_RO(in3_input, in_input, 3);
348 static SENSOR_DEVICE_ATTR_RW(in3_min, in_min, 3);
349 static SENSOR_DEVICE_ATTR_RW(in3_max, in_max, 3);
350 static SENSOR_DEVICE_ATTR_RO(in4_input, in_input, 4);
351 static SENSOR_DEVICE_ATTR_RW(in4_min, in_min, 4);
352 static SENSOR_DEVICE_ATTR_RW(in4_max, in_max, 4);
353 static SENSOR_DEVICE_ATTR_RO(in5_input, in_input, 5);
354 static SENSOR_DEVICE_ATTR_RW(in5_min, in_min, 5);
355 static SENSOR_DEVICE_ATTR_RW(in5_max, in_max, 5);
356 static SENSOR_DEVICE_ATTR_RO(in6_input, in_input, 6);
357 static SENSOR_DEVICE_ATTR_RW(in6_min, in_min, 6);
358 static SENSOR_DEVICE_ATTR_RW(in6_max, in_max, 6);
359 static SENSOR_DEVICE_ATTR_RO(in7_input, in_input, 7);
360 static SENSOR_DEVICE_ATTR_RW(in7_min, in_min, 7);
361 static SENSOR_DEVICE_ATTR_RW(in7_max, in_max, 7);
362 
363 static ssize_t temp_input_show(struct device *dev,
364 			       struct device_attribute *attr, char *buf)
365 {
366 	struct lm87_data *data = lm87_update_device(dev);
367 	int nr = to_sensor_dev_attr(attr)->index;
368 
369 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
370 }
371 
372 static ssize_t temp_low_show(struct device *dev,
373 			     struct device_attribute *attr, char *buf)
374 {
375 	struct lm87_data *data = lm87_update_device(dev);
376 	int nr = to_sensor_dev_attr(attr)->index;
377 
378 	return sprintf(buf, "%d\n",
379 		       TEMP_FROM_REG(data->temp_low[nr]));
380 }
381 
382 static ssize_t temp_high_show(struct device *dev,
383 			      struct device_attribute *attr, char *buf)
384 {
385 	struct lm87_data *data = lm87_update_device(dev);
386 	int nr = to_sensor_dev_attr(attr)->index;
387 
388 	return sprintf(buf, "%d\n",
389 		       TEMP_FROM_REG(data->temp_high[nr]));
390 }
391 
392 static ssize_t temp_low_store(struct device *dev,
393 			      struct device_attribute *attr, const char *buf,
394 			      size_t count)
395 {
396 	struct i2c_client *client = dev_get_drvdata(dev);
397 	struct lm87_data *data = i2c_get_clientdata(client);
398 	int nr = to_sensor_dev_attr(attr)->index;
399 	long val;
400 	int err;
401 
402 	err = kstrtol(buf, 10, &val);
403 	if (err)
404 		return err;
405 
406 	mutex_lock(&data->update_lock);
407 	data->temp_low[nr] = TEMP_TO_REG(val);
408 	lm87_write_value(client, LM87_REG_TEMP_LOW[nr], data->temp_low[nr]);
409 	mutex_unlock(&data->update_lock);
410 	return count;
411 }
412 
413 static ssize_t temp_high_store(struct device *dev,
414 			       struct device_attribute *attr, const char *buf,
415 			       size_t count)
416 {
417 	struct i2c_client *client = dev_get_drvdata(dev);
418 	struct lm87_data *data = i2c_get_clientdata(client);
419 	int nr = to_sensor_dev_attr(attr)->index;
420 	long val;
421 	int err;
422 
423 	err = kstrtol(buf, 10, &val);
424 	if (err)
425 		return err;
426 
427 	mutex_lock(&data->update_lock);
428 	data->temp_high[nr] = TEMP_TO_REG(val);
429 	lm87_write_value(client, LM87_REG_TEMP_HIGH[nr], data->temp_high[nr]);
430 	mutex_unlock(&data->update_lock);
431 	return count;
432 }
433 
434 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
435 static SENSOR_DEVICE_ATTR_RW(temp1_min, temp_low, 0);
436 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_high, 0);
437 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1);
438 static SENSOR_DEVICE_ATTR_RW(temp2_min, temp_low, 1);
439 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_high, 1);
440 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp_input, 2);
441 static SENSOR_DEVICE_ATTR_RW(temp3_min, temp_low, 2);
442 static SENSOR_DEVICE_ATTR_RW(temp3_max, temp_high, 2);
443 
444 static ssize_t temp1_crit_show(struct device *dev,
445 			       struct device_attribute *attr, char *buf)
446 {
447 	struct lm87_data *data = lm87_update_device(dev);
448 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_int));
449 }
450 
451 static ssize_t temp2_crit_show(struct device *dev,
452 			       struct device_attribute *attr, char *buf)
453 {
454 	struct lm87_data *data = lm87_update_device(dev);
455 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_ext));
456 }
457 
458 static DEVICE_ATTR_RO(temp1_crit);
459 static DEVICE_ATTR_RO(temp2_crit);
460 static DEVICE_ATTR(temp3_crit, 0444, temp2_crit_show, NULL);
461 
462 static ssize_t fan_input_show(struct device *dev,
463 			      struct device_attribute *attr, char *buf)
464 {
465 	struct lm87_data *data = lm87_update_device(dev);
466 	int nr = to_sensor_dev_attr(attr)->index;
467 
468 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
469 		       FAN_DIV_FROM_REG(data->fan_div[nr])));
470 }
471 
472 static ssize_t fan_min_show(struct device *dev, struct device_attribute *attr,
473 			    char *buf)
474 {
475 	struct lm87_data *data = lm87_update_device(dev);
476 	int nr = to_sensor_dev_attr(attr)->index;
477 
478 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
479 		       FAN_DIV_FROM_REG(data->fan_div[nr])));
480 }
481 
482 static ssize_t fan_div_show(struct device *dev, struct device_attribute *attr,
483 			    char *buf)
484 {
485 	struct lm87_data *data = lm87_update_device(dev);
486 	int nr = to_sensor_dev_attr(attr)->index;
487 
488 	return sprintf(buf, "%d\n",
489 		       FAN_DIV_FROM_REG(data->fan_div[nr]));
490 }
491 
492 static ssize_t fan_min_store(struct device *dev,
493 			     struct device_attribute *attr, const char *buf,
494 			     size_t count)
495 {
496 	struct i2c_client *client = dev_get_drvdata(dev);
497 	struct lm87_data *data = i2c_get_clientdata(client);
498 	int nr = to_sensor_dev_attr(attr)->index;
499 	long val;
500 	int err;
501 
502 	err = kstrtol(buf, 10, &val);
503 	if (err)
504 		return err;
505 
506 	mutex_lock(&data->update_lock);
507 	data->fan_min[nr] = FAN_TO_REG(val,
508 			    FAN_DIV_FROM_REG(data->fan_div[nr]));
509 	lm87_write_value(client, LM87_REG_FAN_MIN(nr), data->fan_min[nr]);
510 	mutex_unlock(&data->update_lock);
511 	return count;
512 }
513 
514 /*
515  * Note: we save and restore the fan minimum here, because its value is
516  * determined in part by the fan clock divider.  This follows the principle
517  * of least surprise; the user doesn't expect the fan minimum to change just
518  * because the divider changed.
519  */
520 static ssize_t fan_div_store(struct device *dev,
521 			     struct device_attribute *attr, const char *buf,
522 			     size_t count)
523 {
524 	struct i2c_client *client = dev_get_drvdata(dev);
525 	struct lm87_data *data = i2c_get_clientdata(client);
526 	int nr = to_sensor_dev_attr(attr)->index;
527 	long val;
528 	int err;
529 	unsigned long min;
530 	u8 reg;
531 
532 	err = kstrtol(buf, 10, &val);
533 	if (err)
534 		return err;
535 
536 	mutex_lock(&data->update_lock);
537 	min = FAN_FROM_REG(data->fan_min[nr],
538 			   FAN_DIV_FROM_REG(data->fan_div[nr]));
539 
540 	switch (val) {
541 	case 1:
542 		data->fan_div[nr] = 0;
543 		break;
544 	case 2:
545 		data->fan_div[nr] = 1;
546 		break;
547 	case 4:
548 		data->fan_div[nr] = 2;
549 		break;
550 	case 8:
551 		data->fan_div[nr] = 3;
552 		break;
553 	default:
554 		mutex_unlock(&data->update_lock);
555 		return -EINVAL;
556 	}
557 
558 	reg = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
559 	switch (nr) {
560 	case 0:
561 	    reg = (reg & 0xCF) | (data->fan_div[0] << 4);
562 	    break;
563 	case 1:
564 	    reg = (reg & 0x3F) | (data->fan_div[1] << 6);
565 	    break;
566 	}
567 	lm87_write_value(client, LM87_REG_VID_FAN_DIV, reg);
568 
569 	data->fan_min[nr] = FAN_TO_REG(min, val);
570 	lm87_write_value(client, LM87_REG_FAN_MIN(nr),
571 			 data->fan_min[nr]);
572 	mutex_unlock(&data->update_lock);
573 
574 	return count;
575 }
576 
577 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0);
578 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
579 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
580 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1);
581 static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
582 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
583 
584 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
585 			   char *buf)
586 {
587 	struct lm87_data *data = lm87_update_device(dev);
588 	return sprintf(buf, "%d\n", data->alarms);
589 }
590 static DEVICE_ATTR_RO(alarms);
591 
592 static ssize_t cpu0_vid_show(struct device *dev,
593 			     struct device_attribute *attr, char *buf)
594 {
595 	struct lm87_data *data = lm87_update_device(dev);
596 	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
597 }
598 static DEVICE_ATTR_RO(cpu0_vid);
599 
600 static ssize_t vrm_show(struct device *dev, struct device_attribute *attr,
601 			char *buf)
602 {
603 	struct lm87_data *data = dev_get_drvdata(dev);
604 	return sprintf(buf, "%d\n", data->vrm);
605 }
606 static ssize_t vrm_store(struct device *dev, struct device_attribute *attr,
607 			 const char *buf, size_t count)
608 {
609 	struct lm87_data *data = dev_get_drvdata(dev);
610 	unsigned long val;
611 	int err;
612 
613 	err = kstrtoul(buf, 10, &val);
614 	if (err)
615 		return err;
616 
617 	if (val > 255)
618 		return -EINVAL;
619 
620 	data->vrm = val;
621 	return count;
622 }
623 static DEVICE_ATTR_RW(vrm);
624 
625 static ssize_t aout_output_show(struct device *dev,
626 				struct device_attribute *attr, char *buf)
627 {
628 	struct lm87_data *data = lm87_update_device(dev);
629 	return sprintf(buf, "%d\n", AOUT_FROM_REG(data->aout));
630 }
631 static ssize_t aout_output_store(struct device *dev,
632 				 struct device_attribute *attr,
633 				 const char *buf, size_t count)
634 {
635 	struct i2c_client *client = dev_get_drvdata(dev);
636 	struct lm87_data *data = i2c_get_clientdata(client);
637 	long val;
638 	int err;
639 
640 	err = kstrtol(buf, 10, &val);
641 	if (err)
642 		return err;
643 
644 	mutex_lock(&data->update_lock);
645 	data->aout = AOUT_TO_REG(val);
646 	lm87_write_value(client, LM87_REG_AOUT, data->aout);
647 	mutex_unlock(&data->update_lock);
648 	return count;
649 }
650 static DEVICE_ATTR_RW(aout_output);
651 
652 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
653 			  char *buf)
654 {
655 	struct lm87_data *data = lm87_update_device(dev);
656 	int bitnr = to_sensor_dev_attr(attr)->index;
657 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
658 }
659 static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0);
660 static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 1);
661 static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 2);
662 static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 3);
663 static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 8);
664 static SENSOR_DEVICE_ATTR_RO(in5_alarm, alarm, 9);
665 static SENSOR_DEVICE_ATTR_RO(in6_alarm, alarm, 6);
666 static SENSOR_DEVICE_ATTR_RO(in7_alarm, alarm, 7);
667 static SENSOR_DEVICE_ATTR_RO(temp1_alarm, alarm, 4);
668 static SENSOR_DEVICE_ATTR_RO(temp2_alarm, alarm, 5);
669 static SENSOR_DEVICE_ATTR_RO(temp3_alarm, alarm, 5);
670 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, alarm, 6);
671 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, alarm, 7);
672 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 14);
673 static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 15);
674 
675 /*
676  * Real code
677  */
678 
679 static struct attribute *lm87_attributes[] = {
680 	&sensor_dev_attr_in1_input.dev_attr.attr,
681 	&sensor_dev_attr_in1_min.dev_attr.attr,
682 	&sensor_dev_attr_in1_max.dev_attr.attr,
683 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
684 	&sensor_dev_attr_in2_input.dev_attr.attr,
685 	&sensor_dev_attr_in2_min.dev_attr.attr,
686 	&sensor_dev_attr_in2_max.dev_attr.attr,
687 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
688 	&sensor_dev_attr_in3_input.dev_attr.attr,
689 	&sensor_dev_attr_in3_min.dev_attr.attr,
690 	&sensor_dev_attr_in3_max.dev_attr.attr,
691 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
692 	&sensor_dev_attr_in4_input.dev_attr.attr,
693 	&sensor_dev_attr_in4_min.dev_attr.attr,
694 	&sensor_dev_attr_in4_max.dev_attr.attr,
695 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
696 
697 	&sensor_dev_attr_temp1_input.dev_attr.attr,
698 	&sensor_dev_attr_temp1_max.dev_attr.attr,
699 	&sensor_dev_attr_temp1_min.dev_attr.attr,
700 	&dev_attr_temp1_crit.attr,
701 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
702 	&sensor_dev_attr_temp2_input.dev_attr.attr,
703 	&sensor_dev_attr_temp2_max.dev_attr.attr,
704 	&sensor_dev_attr_temp2_min.dev_attr.attr,
705 	&dev_attr_temp2_crit.attr,
706 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
707 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
708 
709 	&dev_attr_alarms.attr,
710 	&dev_attr_aout_output.attr,
711 
712 	NULL
713 };
714 
715 static const struct attribute_group lm87_group = {
716 	.attrs = lm87_attributes,
717 };
718 
719 static struct attribute *lm87_attributes_in6[] = {
720 	&sensor_dev_attr_in6_input.dev_attr.attr,
721 	&sensor_dev_attr_in6_min.dev_attr.attr,
722 	&sensor_dev_attr_in6_max.dev_attr.attr,
723 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
724 	NULL
725 };
726 
727 static const struct attribute_group lm87_group_in6 = {
728 	.attrs = lm87_attributes_in6,
729 };
730 
731 static struct attribute *lm87_attributes_fan1[] = {
732 	&sensor_dev_attr_fan1_input.dev_attr.attr,
733 	&sensor_dev_attr_fan1_min.dev_attr.attr,
734 	&sensor_dev_attr_fan1_div.dev_attr.attr,
735 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
736 	NULL
737 };
738 
739 static const struct attribute_group lm87_group_fan1 = {
740 	.attrs = lm87_attributes_fan1,
741 };
742 
743 static struct attribute *lm87_attributes_in7[] = {
744 	&sensor_dev_attr_in7_input.dev_attr.attr,
745 	&sensor_dev_attr_in7_min.dev_attr.attr,
746 	&sensor_dev_attr_in7_max.dev_attr.attr,
747 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
748 	NULL
749 };
750 
751 static const struct attribute_group lm87_group_in7 = {
752 	.attrs = lm87_attributes_in7,
753 };
754 
755 static struct attribute *lm87_attributes_fan2[] = {
756 	&sensor_dev_attr_fan2_input.dev_attr.attr,
757 	&sensor_dev_attr_fan2_min.dev_attr.attr,
758 	&sensor_dev_attr_fan2_div.dev_attr.attr,
759 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
760 	NULL
761 };
762 
763 static const struct attribute_group lm87_group_fan2 = {
764 	.attrs = lm87_attributes_fan2,
765 };
766 
767 static struct attribute *lm87_attributes_temp3[] = {
768 	&sensor_dev_attr_temp3_input.dev_attr.attr,
769 	&sensor_dev_attr_temp3_max.dev_attr.attr,
770 	&sensor_dev_attr_temp3_min.dev_attr.attr,
771 	&dev_attr_temp3_crit.attr,
772 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
773 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
774 	NULL
775 };
776 
777 static const struct attribute_group lm87_group_temp3 = {
778 	.attrs = lm87_attributes_temp3,
779 };
780 
781 static struct attribute *lm87_attributes_in0_5[] = {
782 	&sensor_dev_attr_in0_input.dev_attr.attr,
783 	&sensor_dev_attr_in0_min.dev_attr.attr,
784 	&sensor_dev_attr_in0_max.dev_attr.attr,
785 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
786 	&sensor_dev_attr_in5_input.dev_attr.attr,
787 	&sensor_dev_attr_in5_min.dev_attr.attr,
788 	&sensor_dev_attr_in5_max.dev_attr.attr,
789 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
790 	NULL
791 };
792 
793 static const struct attribute_group lm87_group_in0_5 = {
794 	.attrs = lm87_attributes_in0_5,
795 };
796 
797 static struct attribute *lm87_attributes_vid[] = {
798 	&dev_attr_cpu0_vid.attr,
799 	&dev_attr_vrm.attr,
800 	NULL
801 };
802 
803 static const struct attribute_group lm87_group_vid = {
804 	.attrs = lm87_attributes_vid,
805 };
806 
807 /* Return 0 if detection is successful, -ENODEV otherwise */
808 static int lm87_detect(struct i2c_client *client, struct i2c_board_info *info)
809 {
810 	struct i2c_adapter *adapter = client->adapter;
811 	const char *name;
812 	u8 cid, rev;
813 
814 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
815 		return -ENODEV;
816 
817 	if (lm87_read_value(client, LM87_REG_CONFIG) & 0x80)
818 		return -ENODEV;
819 
820 	/* Now, we do the remaining detection. */
821 	cid = lm87_read_value(client, LM87_REG_COMPANY_ID);
822 	rev = lm87_read_value(client, LM87_REG_REVISION);
823 
824 	if (cid == 0x02			/* National Semiconductor */
825 	 && (rev >= 0x01 && rev <= 0x08))
826 		name = "lm87";
827 	else if (cid == 0x41		/* Analog Devices */
828 	      && (rev & 0xf0) == 0x10)
829 		name = "adm1024";
830 	else {
831 		dev_dbg(&adapter->dev, "LM87 detection failed at 0x%02x\n",
832 			client->addr);
833 		return -ENODEV;
834 	}
835 
836 	strscpy(info->type, name, I2C_NAME_SIZE);
837 
838 	return 0;
839 }
840 
841 static void lm87_restore_config(void *arg)
842 {
843 	struct i2c_client *client = arg;
844 	struct lm87_data *data = i2c_get_clientdata(client);
845 
846 	lm87_write_value(client, LM87_REG_CONFIG, data->config);
847 }
848 
849 static int lm87_init_client(struct i2c_client *client)
850 {
851 	struct lm87_data *data = i2c_get_clientdata(client);
852 	int rc;
853 	struct device_node *of_node = client->dev.of_node;
854 	u8 val = 0;
855 	struct regulator *vcc = NULL;
856 
857 	if (of_node) {
858 		if (of_property_read_bool(of_node, "has-temp3"))
859 			val |= CHAN_TEMP3;
860 		if (of_property_read_bool(of_node, "has-in6"))
861 			val |= CHAN_NO_FAN(0);
862 		if (of_property_read_bool(of_node, "has-in7"))
863 			val |= CHAN_NO_FAN(1);
864 		vcc = devm_regulator_get_optional(&client->dev, "vcc");
865 		if (!IS_ERR(vcc)) {
866 			if (regulator_get_voltage(vcc) == 5000000)
867 				val |= CHAN_VCC_5V;
868 		}
869 		data->channel = val;
870 		lm87_write_value(client,
871 				LM87_REG_CHANNEL_MODE, data->channel);
872 	} else if (dev_get_platdata(&client->dev)) {
873 		data->channel = *(u8 *)dev_get_platdata(&client->dev);
874 		lm87_write_value(client,
875 				 LM87_REG_CHANNEL_MODE, data->channel);
876 	} else {
877 		data->channel = lm87_read_value(client, LM87_REG_CHANNEL_MODE);
878 	}
879 	data->config = lm87_read_value(client, LM87_REG_CONFIG) & 0x6F;
880 
881 	rc = devm_add_action(&client->dev, lm87_restore_config, client);
882 	if (rc)
883 		return rc;
884 
885 	if (!(data->config & 0x01)) {
886 		int i;
887 
888 		/* Limits are left uninitialized after power-up */
889 		for (i = 1; i < 6; i++) {
890 			lm87_write_value(client, LM87_REG_IN_MIN(i), 0x00);
891 			lm87_write_value(client, LM87_REG_IN_MAX(i), 0xFF);
892 		}
893 		for (i = 0; i < 2; i++) {
894 			lm87_write_value(client, LM87_REG_TEMP_HIGH[i], 0x7F);
895 			lm87_write_value(client, LM87_REG_TEMP_LOW[i], 0x00);
896 			lm87_write_value(client, LM87_REG_AIN_MIN(i), 0x00);
897 			lm87_write_value(client, LM87_REG_AIN_MAX(i), 0xFF);
898 		}
899 		if (data->channel & CHAN_TEMP3) {
900 			lm87_write_value(client, LM87_REG_TEMP_HIGH[2], 0x7F);
901 			lm87_write_value(client, LM87_REG_TEMP_LOW[2], 0x00);
902 		} else {
903 			lm87_write_value(client, LM87_REG_IN_MIN(0), 0x00);
904 			lm87_write_value(client, LM87_REG_IN_MAX(0), 0xFF);
905 		}
906 	}
907 
908 	/* Make sure Start is set and INT#_Clear is clear */
909 	if ((data->config & 0x09) != 0x01)
910 		lm87_write_value(client, LM87_REG_CONFIG,
911 				 (data->config & 0x77) | 0x01);
912 	return 0;
913 }
914 
915 static int lm87_probe(struct i2c_client *client)
916 {
917 	struct lm87_data *data;
918 	struct device *hwmon_dev;
919 	int err;
920 	unsigned int group_tail = 0;
921 
922 	data = devm_kzalloc(&client->dev, sizeof(struct lm87_data), GFP_KERNEL);
923 	if (!data)
924 		return -ENOMEM;
925 
926 	i2c_set_clientdata(client, data);
927 	mutex_init(&data->update_lock);
928 
929 	/* Initialize the LM87 chip */
930 	err = lm87_init_client(client);
931 	if (err)
932 		return err;
933 
934 	data->in_scale[0] = 2500;
935 	data->in_scale[1] = 2700;
936 	data->in_scale[2] = (data->channel & CHAN_VCC_5V) ? 5000 : 3300;
937 	data->in_scale[3] = 5000;
938 	data->in_scale[4] = 12000;
939 	data->in_scale[5] = 2700;
940 	data->in_scale[6] = 1875;
941 	data->in_scale[7] = 1875;
942 
943 	/*
944 	 * Construct the list of attributes, the list depends on the
945 	 * configuration of the chip
946 	 */
947 	data->attr_groups[group_tail++] = &lm87_group;
948 	if (data->channel & CHAN_NO_FAN(0))
949 		data->attr_groups[group_tail++] = &lm87_group_in6;
950 	else
951 		data->attr_groups[group_tail++] = &lm87_group_fan1;
952 
953 	if (data->channel & CHAN_NO_FAN(1))
954 		data->attr_groups[group_tail++] = &lm87_group_in7;
955 	else
956 		data->attr_groups[group_tail++] = &lm87_group_fan2;
957 
958 	if (data->channel & CHAN_TEMP3)
959 		data->attr_groups[group_tail++] = &lm87_group_temp3;
960 	else
961 		data->attr_groups[group_tail++] = &lm87_group_in0_5;
962 
963 	if (!(data->channel & CHAN_NO_VID)) {
964 		data->vrm = vid_which_vrm();
965 		data->attr_groups[group_tail++] = &lm87_group_vid;
966 	}
967 
968 	hwmon_dev = devm_hwmon_device_register_with_groups(
969 	    &client->dev, client->name, client, data->attr_groups);
970 	return PTR_ERR_OR_ZERO(hwmon_dev);
971 }
972 
973 /*
974  * Driver data (common to all clients)
975  */
976 
977 static const struct i2c_device_id lm87_id[] = {
978 	{ "lm87", 0 },
979 	{ "adm1024", 0 },
980 	{ }
981 };
982 MODULE_DEVICE_TABLE(i2c, lm87_id);
983 
984 static const struct of_device_id lm87_of_match[] = {
985 	{ .compatible = "ti,lm87" },
986 	{ .compatible = "adi,adm1024" },
987 	{ },
988 };
989 MODULE_DEVICE_TABLE(of, lm87_of_match);
990 
991 static struct i2c_driver lm87_driver = {
992 	.class		= I2C_CLASS_HWMON,
993 	.driver = {
994 		.name	= "lm87",
995 		.of_match_table = lm87_of_match,
996 	},
997 	.probe		= lm87_probe,
998 	.id_table	= lm87_id,
999 	.detect		= lm87_detect,
1000 	.address_list	= normal_i2c,
1001 };
1002 
1003 module_i2c_driver(lm87_driver);
1004 
1005 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de> and others");
1006 MODULE_DESCRIPTION("LM87 driver");
1007 MODULE_LICENSE("GPL");
1008