xref: /openbmc/linux/drivers/hwmon/lm87.c (revision ec8f24b7)
1 /*
2  * lm87.c
3  *
4  * Copyright (C) 2000       Frodo Looijaard <frodol@dds.nl>
5  *                          Philip Edelbrock <phil@netroedge.com>
6  *                          Stephen Rousset <stephen.rousset@rocketlogix.com>
7  *                          Dan Eaton <dan.eaton@rocketlogix.com>
8  * Copyright (C) 2004-2008  Jean Delvare <jdelvare@suse.de>
9  *
10  * Original port to Linux 2.6 by Jeff Oliver.
11  *
12  * The LM87 is a sensor chip made by National Semiconductor. It monitors up
13  * to 8 voltages (including its own power source), up to three temperatures
14  * (its own plus up to two external ones) and up to two fans. The default
15  * configuration is 6 voltages, two temperatures and two fans (see below).
16  * Voltages are scaled internally with ratios such that the nominal value of
17  * each voltage correspond to a register value of 192 (which means a
18  * resolution of about 0.5% of the nominal value). Temperature values are
19  * reported with a 1 deg resolution and a 3-4 deg accuracy. Complete
20  * datasheet can be obtained from National's website at:
21  *   http://www.national.com/pf/LM/LM87.html
22  *
23  * Some functions share pins, so not all functions are available at the same
24  * time. Which are depends on the hardware setup. This driver normally
25  * assumes that firmware configured the chip correctly. Where this is not
26  * the case, platform code must set the I2C client's platform_data to point
27  * to a u8 value to be written to the channel register.
28  * For reference, here is the list of exclusive functions:
29  *  - in0+in5 (default) or temp3
30  *  - fan1 (default) or in6
31  *  - fan2 (default) or in7
32  *  - VID lines (default) or IRQ lines (not handled by this driver)
33  *
34  * The LM87 additionally features an analog output, supposedly usable to
35  * control the speed of a fan. All new chips use pulse width modulation
36  * instead. The LM87 is the only hardware monitoring chipset I know of
37  * which uses amplitude modulation. Be careful when using this feature.
38  *
39  * This driver also supports the ADM1024, a sensor chip made by Analog
40  * Devices. That chip is fully compatible with the LM87. Complete
41  * datasheet can be obtained from Analog's website at:
42  *   http://www.analog.com/en/prod/0,2877,ADM1024,00.html
43  *
44  * This program is free software; you can redistribute it and/or modify
45  * it under the terms of the GNU General Public License as published by
46  * the Free Software Foundation; either version 2 of the License, or
47  * (at your option) any later version.
48  *
49  * This program is distributed in the hope that it will be useful,
50  * but WITHOUT ANY WARRANTY; without even the implied warranty of
51  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
52  * GNU General Public License for more details.
53  *
54  * You should have received a copy of the GNU General Public License
55  * along with this program; if not, write to the Free Software
56  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
57  */
58 
59 #include <linux/module.h>
60 #include <linux/init.h>
61 #include <linux/slab.h>
62 #include <linux/jiffies.h>
63 #include <linux/i2c.h>
64 #include <linux/hwmon.h>
65 #include <linux/hwmon-sysfs.h>
66 #include <linux/hwmon-vid.h>
67 #include <linux/err.h>
68 #include <linux/mutex.h>
69 #include <linux/regulator/consumer.h>
70 
71 /*
72  * Addresses to scan
73  * LM87 has three possible addresses: 0x2c, 0x2d and 0x2e.
74  */
75 
76 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };
77 
78 /*
79  * The LM87 registers
80  */
81 
82 /* nr in 0..5 */
83 #define LM87_REG_IN(nr)			(0x20 + (nr))
84 #define LM87_REG_IN_MAX(nr)		(0x2B + (nr) * 2)
85 #define LM87_REG_IN_MIN(nr)		(0x2C + (nr) * 2)
86 /* nr in 0..1 */
87 #define LM87_REG_AIN(nr)		(0x28 + (nr))
88 #define LM87_REG_AIN_MIN(nr)		(0x1A + (nr))
89 #define LM87_REG_AIN_MAX(nr)		(0x3B + (nr))
90 
91 static u8 LM87_REG_TEMP[3] = { 0x27, 0x26, 0x20 };
92 static u8 LM87_REG_TEMP_HIGH[3] = { 0x39, 0x37, 0x2B };
93 static u8 LM87_REG_TEMP_LOW[3] = { 0x3A, 0x38, 0x2C };
94 
95 #define LM87_REG_TEMP_HW_INT_LOCK	0x13
96 #define LM87_REG_TEMP_HW_EXT_LOCK	0x14
97 #define LM87_REG_TEMP_HW_INT		0x17
98 #define LM87_REG_TEMP_HW_EXT		0x18
99 
100 /* nr in 0..1 */
101 #define LM87_REG_FAN(nr)		(0x28 + (nr))
102 #define LM87_REG_FAN_MIN(nr)		(0x3B + (nr))
103 #define LM87_REG_AOUT			0x19
104 
105 #define LM87_REG_CONFIG			0x40
106 #define LM87_REG_CHANNEL_MODE		0x16
107 #define LM87_REG_VID_FAN_DIV		0x47
108 #define LM87_REG_VID4			0x49
109 
110 #define LM87_REG_ALARMS1		0x41
111 #define LM87_REG_ALARMS2		0x42
112 
113 #define LM87_REG_COMPANY_ID		0x3E
114 #define LM87_REG_REVISION		0x3F
115 
116 /*
117  * Conversions and various macros
118  * The LM87 uses signed 8-bit values for temperatures.
119  */
120 
121 #define IN_FROM_REG(reg, scale)	(((reg) * (scale) + 96) / 192)
122 #define IN_TO_REG(val, scale)	((val) <= 0 ? 0 : \
123 				 (val) >= (scale) * 255 / 192 ? 255 : \
124 				 ((val) * 192 + (scale) / 2) / (scale))
125 
126 #define TEMP_FROM_REG(reg)	((reg) * 1000)
127 #define TEMP_TO_REG(val)	((val) <= -127500 ? -128 : \
128 				 (val) >= 126500 ? 127 : \
129 				 (((val) < 0 ? (val) - 500 : \
130 				   (val) + 500) / 1000))
131 
132 #define FAN_FROM_REG(reg, div)	((reg) == 255 || (reg) == 0 ? 0 : \
133 				 (1350000 + (reg)*(div) / 2) / ((reg) * (div)))
134 #define FAN_TO_REG(val, div)	((val) * (div) * 255 <= 1350000 ? 255 : \
135 				 (1350000 + (val)*(div) / 2) / ((val) * (div)))
136 
137 #define FAN_DIV_FROM_REG(reg)	(1 << (reg))
138 
139 /* analog out is 9.80mV/LSB */
140 #define AOUT_FROM_REG(reg)	(((reg) * 98 + 5) / 10)
141 #define AOUT_TO_REG(val)	((val) <= 0 ? 0 : \
142 				 (val) >= 2500 ? 255 : \
143 				 ((val) * 10 + 49) / 98)
144 
145 /* nr in 0..1 */
146 #define CHAN_NO_FAN(nr)		(1 << (nr))
147 #define CHAN_TEMP3		(1 << 2)
148 #define CHAN_VCC_5V		(1 << 3)
149 #define CHAN_NO_VID		(1 << 7)
150 
151 /*
152  * Client data (each client gets its own)
153  */
154 
155 struct lm87_data {
156 	struct mutex update_lock;
157 	char valid; /* zero until following fields are valid */
158 	unsigned long last_updated; /* In jiffies */
159 
160 	u8 channel;		/* register value */
161 	u8 config;		/* original register value */
162 
163 	u8 in[8];		/* register value */
164 	u8 in_max[8];		/* register value */
165 	u8 in_min[8];		/* register value */
166 	u16 in_scale[8];
167 
168 	s8 temp[3];		/* register value */
169 	s8 temp_high[3];	/* register value */
170 	s8 temp_low[3];		/* register value */
171 	s8 temp_crit_int;	/* min of two register values */
172 	s8 temp_crit_ext;	/* min of two register values */
173 
174 	u8 fan[2];		/* register value */
175 	u8 fan_min[2];		/* register value */
176 	u8 fan_div[2];		/* register value, shifted right */
177 	u8 aout;		/* register value */
178 
179 	u16 alarms;		/* register values, combined */
180 	u8 vid;			/* register values, combined */
181 	u8 vrm;
182 
183 	const struct attribute_group *attr_groups[6];
184 };
185 
186 static inline int lm87_read_value(struct i2c_client *client, u8 reg)
187 {
188 	return i2c_smbus_read_byte_data(client, reg);
189 }
190 
191 static inline int lm87_write_value(struct i2c_client *client, u8 reg, u8 value)
192 {
193 	return i2c_smbus_write_byte_data(client, reg, value);
194 }
195 
196 static struct lm87_data *lm87_update_device(struct device *dev)
197 {
198 	struct i2c_client *client = dev_get_drvdata(dev);
199 	struct lm87_data *data = i2c_get_clientdata(client);
200 
201 	mutex_lock(&data->update_lock);
202 
203 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
204 		int i, j;
205 
206 		dev_dbg(&client->dev, "Updating data.\n");
207 
208 		i = (data->channel & CHAN_TEMP3) ? 1 : 0;
209 		j = (data->channel & CHAN_TEMP3) ? 5 : 6;
210 		for (; i < j; i++) {
211 			data->in[i] = lm87_read_value(client,
212 				      LM87_REG_IN(i));
213 			data->in_min[i] = lm87_read_value(client,
214 					  LM87_REG_IN_MIN(i));
215 			data->in_max[i] = lm87_read_value(client,
216 					  LM87_REG_IN_MAX(i));
217 		}
218 
219 		for (i = 0; i < 2; i++) {
220 			if (data->channel & CHAN_NO_FAN(i)) {
221 				data->in[6+i] = lm87_read_value(client,
222 						LM87_REG_AIN(i));
223 				data->in_max[6+i] = lm87_read_value(client,
224 						    LM87_REG_AIN_MAX(i));
225 				data->in_min[6+i] = lm87_read_value(client,
226 						    LM87_REG_AIN_MIN(i));
227 
228 			} else {
229 				data->fan[i] = lm87_read_value(client,
230 					       LM87_REG_FAN(i));
231 				data->fan_min[i] = lm87_read_value(client,
232 						   LM87_REG_FAN_MIN(i));
233 			}
234 		}
235 
236 		j = (data->channel & CHAN_TEMP3) ? 3 : 2;
237 		for (i = 0 ; i < j; i++) {
238 			data->temp[i] = lm87_read_value(client,
239 					LM87_REG_TEMP[i]);
240 			data->temp_high[i] = lm87_read_value(client,
241 					     LM87_REG_TEMP_HIGH[i]);
242 			data->temp_low[i] = lm87_read_value(client,
243 					    LM87_REG_TEMP_LOW[i]);
244 		}
245 
246 		i = lm87_read_value(client, LM87_REG_TEMP_HW_INT_LOCK);
247 		j = lm87_read_value(client, LM87_REG_TEMP_HW_INT);
248 		data->temp_crit_int = min(i, j);
249 
250 		i = lm87_read_value(client, LM87_REG_TEMP_HW_EXT_LOCK);
251 		j = lm87_read_value(client, LM87_REG_TEMP_HW_EXT);
252 		data->temp_crit_ext = min(i, j);
253 
254 		i = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
255 		data->fan_div[0] = (i >> 4) & 0x03;
256 		data->fan_div[1] = (i >> 6) & 0x03;
257 		data->vid = (i & 0x0F)
258 			  | (lm87_read_value(client, LM87_REG_VID4) & 0x01)
259 			     << 4;
260 
261 		data->alarms = lm87_read_value(client, LM87_REG_ALARMS1)
262 			     | (lm87_read_value(client, LM87_REG_ALARMS2)
263 				<< 8);
264 		data->aout = lm87_read_value(client, LM87_REG_AOUT);
265 
266 		data->last_updated = jiffies;
267 		data->valid = 1;
268 	}
269 
270 	mutex_unlock(&data->update_lock);
271 
272 	return data;
273 }
274 
275 /*
276  * Sysfs stuff
277  */
278 
279 static ssize_t in_input_show(struct device *dev,
280 			     struct device_attribute *attr, char *buf)
281 {
282 	struct lm87_data *data = lm87_update_device(dev);
283 	int nr = to_sensor_dev_attr(attr)->index;
284 
285 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in[nr],
286 		       data->in_scale[nr]));
287 }
288 
289 static ssize_t in_min_show(struct device *dev, struct device_attribute *attr,
290 			   char *buf)
291 {
292 	struct lm87_data *data = lm87_update_device(dev);
293 	int nr = to_sensor_dev_attr(attr)->index;
294 
295 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_min[nr],
296 		       data->in_scale[nr]));
297 }
298 
299 static ssize_t in_max_show(struct device *dev, struct device_attribute *attr,
300 			   char *buf)
301 {
302 	struct lm87_data *data = lm87_update_device(dev);
303 	int nr = to_sensor_dev_attr(attr)->index;
304 
305 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_max[nr],
306 		       data->in_scale[nr]));
307 }
308 
309 static ssize_t in_min_store(struct device *dev, struct device_attribute *attr,
310 			    const char *buf, size_t count)
311 {
312 	struct i2c_client *client = dev_get_drvdata(dev);
313 	struct lm87_data *data = i2c_get_clientdata(client);
314 	int nr = to_sensor_dev_attr(attr)->index;
315 	long val;
316 	int err;
317 
318 	err = kstrtol(buf, 10, &val);
319 	if (err)
320 		return err;
321 
322 	mutex_lock(&data->update_lock);
323 	data->in_min[nr] = IN_TO_REG(val, data->in_scale[nr]);
324 	lm87_write_value(client, nr < 6 ? LM87_REG_IN_MIN(nr) :
325 			 LM87_REG_AIN_MIN(nr - 6), data->in_min[nr]);
326 	mutex_unlock(&data->update_lock);
327 	return count;
328 }
329 
330 static ssize_t in_max_store(struct device *dev, struct device_attribute *attr,
331 			    const char *buf, size_t count)
332 {
333 	struct i2c_client *client = dev_get_drvdata(dev);
334 	struct lm87_data *data = i2c_get_clientdata(client);
335 	int nr = to_sensor_dev_attr(attr)->index;
336 	long val;
337 	int err;
338 
339 	err = kstrtol(buf, 10, &val);
340 	if (err)
341 		return err;
342 
343 	mutex_lock(&data->update_lock);
344 	data->in_max[nr] = IN_TO_REG(val, data->in_scale[nr]);
345 	lm87_write_value(client, nr < 6 ? LM87_REG_IN_MAX(nr) :
346 			 LM87_REG_AIN_MAX(nr - 6), data->in_max[nr]);
347 	mutex_unlock(&data->update_lock);
348 	return count;
349 }
350 
351 static SENSOR_DEVICE_ATTR_RO(in0_input, in_input, 0);
352 static SENSOR_DEVICE_ATTR_RW(in0_min, in_min, 0);
353 static SENSOR_DEVICE_ATTR_RW(in0_max, in_max, 0);
354 static SENSOR_DEVICE_ATTR_RO(in1_input, in_input, 1);
355 static SENSOR_DEVICE_ATTR_RW(in1_min, in_min, 1);
356 static SENSOR_DEVICE_ATTR_RW(in1_max, in_max, 1);
357 static SENSOR_DEVICE_ATTR_RO(in2_input, in_input, 2);
358 static SENSOR_DEVICE_ATTR_RW(in2_min, in_min, 2);
359 static SENSOR_DEVICE_ATTR_RW(in2_max, in_max, 2);
360 static SENSOR_DEVICE_ATTR_RO(in3_input, in_input, 3);
361 static SENSOR_DEVICE_ATTR_RW(in3_min, in_min, 3);
362 static SENSOR_DEVICE_ATTR_RW(in3_max, in_max, 3);
363 static SENSOR_DEVICE_ATTR_RO(in4_input, in_input, 4);
364 static SENSOR_DEVICE_ATTR_RW(in4_min, in_min, 4);
365 static SENSOR_DEVICE_ATTR_RW(in4_max, in_max, 4);
366 static SENSOR_DEVICE_ATTR_RO(in5_input, in_input, 5);
367 static SENSOR_DEVICE_ATTR_RW(in5_min, in_min, 5);
368 static SENSOR_DEVICE_ATTR_RW(in5_max, in_max, 5);
369 static SENSOR_DEVICE_ATTR_RO(in6_input, in_input, 6);
370 static SENSOR_DEVICE_ATTR_RW(in6_min, in_min, 6);
371 static SENSOR_DEVICE_ATTR_RW(in6_max, in_max, 6);
372 static SENSOR_DEVICE_ATTR_RO(in7_input, in_input, 7);
373 static SENSOR_DEVICE_ATTR_RW(in7_min, in_min, 7);
374 static SENSOR_DEVICE_ATTR_RW(in7_max, in_max, 7);
375 
376 static ssize_t temp_input_show(struct device *dev,
377 			       struct device_attribute *attr, char *buf)
378 {
379 	struct lm87_data *data = lm87_update_device(dev);
380 	int nr = to_sensor_dev_attr(attr)->index;
381 
382 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
383 }
384 
385 static ssize_t temp_low_show(struct device *dev,
386 			     struct device_attribute *attr, char *buf)
387 {
388 	struct lm87_data *data = lm87_update_device(dev);
389 	int nr = to_sensor_dev_attr(attr)->index;
390 
391 	return sprintf(buf, "%d\n",
392 		       TEMP_FROM_REG(data->temp_low[nr]));
393 }
394 
395 static ssize_t temp_high_show(struct device *dev,
396 			      struct device_attribute *attr, char *buf)
397 {
398 	struct lm87_data *data = lm87_update_device(dev);
399 	int nr = to_sensor_dev_attr(attr)->index;
400 
401 	return sprintf(buf, "%d\n",
402 		       TEMP_FROM_REG(data->temp_high[nr]));
403 }
404 
405 static ssize_t temp_low_store(struct device *dev,
406 			      struct device_attribute *attr, const char *buf,
407 			      size_t count)
408 {
409 	struct i2c_client *client = dev_get_drvdata(dev);
410 	struct lm87_data *data = i2c_get_clientdata(client);
411 	int nr = to_sensor_dev_attr(attr)->index;
412 	long val;
413 	int err;
414 
415 	err = kstrtol(buf, 10, &val);
416 	if (err)
417 		return err;
418 
419 	mutex_lock(&data->update_lock);
420 	data->temp_low[nr] = TEMP_TO_REG(val);
421 	lm87_write_value(client, LM87_REG_TEMP_LOW[nr], data->temp_low[nr]);
422 	mutex_unlock(&data->update_lock);
423 	return count;
424 }
425 
426 static ssize_t temp_high_store(struct device *dev,
427 			       struct device_attribute *attr, const char *buf,
428 			       size_t count)
429 {
430 	struct i2c_client *client = dev_get_drvdata(dev);
431 	struct lm87_data *data = i2c_get_clientdata(client);
432 	int nr = to_sensor_dev_attr(attr)->index;
433 	long val;
434 	int err;
435 
436 	err = kstrtol(buf, 10, &val);
437 	if (err)
438 		return err;
439 
440 	mutex_lock(&data->update_lock);
441 	data->temp_high[nr] = TEMP_TO_REG(val);
442 	lm87_write_value(client, LM87_REG_TEMP_HIGH[nr], data->temp_high[nr]);
443 	mutex_unlock(&data->update_lock);
444 	return count;
445 }
446 
447 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
448 static SENSOR_DEVICE_ATTR_RW(temp1_min, temp_low, 0);
449 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_high, 0);
450 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1);
451 static SENSOR_DEVICE_ATTR_RW(temp2_min, temp_low, 1);
452 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_high, 1);
453 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp_input, 2);
454 static SENSOR_DEVICE_ATTR_RW(temp3_min, temp_low, 2);
455 static SENSOR_DEVICE_ATTR_RW(temp3_max, temp_high, 2);
456 
457 static ssize_t temp1_crit_show(struct device *dev,
458 			       struct device_attribute *attr, char *buf)
459 {
460 	struct lm87_data *data = lm87_update_device(dev);
461 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_int));
462 }
463 
464 static ssize_t temp2_crit_show(struct device *dev,
465 			       struct device_attribute *attr, char *buf)
466 {
467 	struct lm87_data *data = lm87_update_device(dev);
468 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_ext));
469 }
470 
471 static DEVICE_ATTR_RO(temp1_crit);
472 static DEVICE_ATTR_RO(temp2_crit);
473 static DEVICE_ATTR(temp3_crit, 0444, temp2_crit_show, NULL);
474 
475 static ssize_t fan_input_show(struct device *dev,
476 			      struct device_attribute *attr, char *buf)
477 {
478 	struct lm87_data *data = lm87_update_device(dev);
479 	int nr = to_sensor_dev_attr(attr)->index;
480 
481 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
482 		       FAN_DIV_FROM_REG(data->fan_div[nr])));
483 }
484 
485 static ssize_t fan_min_show(struct device *dev, struct device_attribute *attr,
486 			    char *buf)
487 {
488 	struct lm87_data *data = lm87_update_device(dev);
489 	int nr = to_sensor_dev_attr(attr)->index;
490 
491 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
492 		       FAN_DIV_FROM_REG(data->fan_div[nr])));
493 }
494 
495 static ssize_t fan_div_show(struct device *dev, struct device_attribute *attr,
496 			    char *buf)
497 {
498 	struct lm87_data *data = lm87_update_device(dev);
499 	int nr = to_sensor_dev_attr(attr)->index;
500 
501 	return sprintf(buf, "%d\n",
502 		       FAN_DIV_FROM_REG(data->fan_div[nr]));
503 }
504 
505 static ssize_t fan_min_store(struct device *dev,
506 			     struct device_attribute *attr, const char *buf,
507 			     size_t count)
508 {
509 	struct i2c_client *client = dev_get_drvdata(dev);
510 	struct lm87_data *data = i2c_get_clientdata(client);
511 	int nr = to_sensor_dev_attr(attr)->index;
512 	long val;
513 	int err;
514 
515 	err = kstrtol(buf, 10, &val);
516 	if (err)
517 		return err;
518 
519 	mutex_lock(&data->update_lock);
520 	data->fan_min[nr] = FAN_TO_REG(val,
521 			    FAN_DIV_FROM_REG(data->fan_div[nr]));
522 	lm87_write_value(client, LM87_REG_FAN_MIN(nr), data->fan_min[nr]);
523 	mutex_unlock(&data->update_lock);
524 	return count;
525 }
526 
527 /*
528  * Note: we save and restore the fan minimum here, because its value is
529  * determined in part by the fan clock divider.  This follows the principle
530  * of least surprise; the user doesn't expect the fan minimum to change just
531  * because the divider changed.
532  */
533 static ssize_t fan_div_store(struct device *dev,
534 			     struct device_attribute *attr, const char *buf,
535 			     size_t count)
536 {
537 	struct i2c_client *client = dev_get_drvdata(dev);
538 	struct lm87_data *data = i2c_get_clientdata(client);
539 	int nr = to_sensor_dev_attr(attr)->index;
540 	long val;
541 	int err;
542 	unsigned long min;
543 	u8 reg;
544 
545 	err = kstrtol(buf, 10, &val);
546 	if (err)
547 		return err;
548 
549 	mutex_lock(&data->update_lock);
550 	min = FAN_FROM_REG(data->fan_min[nr],
551 			   FAN_DIV_FROM_REG(data->fan_div[nr]));
552 
553 	switch (val) {
554 	case 1:
555 		data->fan_div[nr] = 0;
556 		break;
557 	case 2:
558 		data->fan_div[nr] = 1;
559 		break;
560 	case 4:
561 		data->fan_div[nr] = 2;
562 		break;
563 	case 8:
564 		data->fan_div[nr] = 3;
565 		break;
566 	default:
567 		mutex_unlock(&data->update_lock);
568 		return -EINVAL;
569 	}
570 
571 	reg = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
572 	switch (nr) {
573 	case 0:
574 	    reg = (reg & 0xCF) | (data->fan_div[0] << 4);
575 	    break;
576 	case 1:
577 	    reg = (reg & 0x3F) | (data->fan_div[1] << 6);
578 	    break;
579 	}
580 	lm87_write_value(client, LM87_REG_VID_FAN_DIV, reg);
581 
582 	data->fan_min[nr] = FAN_TO_REG(min, val);
583 	lm87_write_value(client, LM87_REG_FAN_MIN(nr),
584 			 data->fan_min[nr]);
585 	mutex_unlock(&data->update_lock);
586 
587 	return count;
588 }
589 
590 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0);
591 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
592 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
593 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1);
594 static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
595 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
596 
597 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
598 			   char *buf)
599 {
600 	struct lm87_data *data = lm87_update_device(dev);
601 	return sprintf(buf, "%d\n", data->alarms);
602 }
603 static DEVICE_ATTR_RO(alarms);
604 
605 static ssize_t cpu0_vid_show(struct device *dev,
606 			     struct device_attribute *attr, char *buf)
607 {
608 	struct lm87_data *data = lm87_update_device(dev);
609 	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
610 }
611 static DEVICE_ATTR_RO(cpu0_vid);
612 
613 static ssize_t vrm_show(struct device *dev, struct device_attribute *attr,
614 			char *buf)
615 {
616 	struct lm87_data *data = dev_get_drvdata(dev);
617 	return sprintf(buf, "%d\n", data->vrm);
618 }
619 static ssize_t vrm_store(struct device *dev, struct device_attribute *attr,
620 			 const char *buf, size_t count)
621 {
622 	struct lm87_data *data = dev_get_drvdata(dev);
623 	unsigned long val;
624 	int err;
625 
626 	err = kstrtoul(buf, 10, &val);
627 	if (err)
628 		return err;
629 
630 	if (val > 255)
631 		return -EINVAL;
632 
633 	data->vrm = val;
634 	return count;
635 }
636 static DEVICE_ATTR_RW(vrm);
637 
638 static ssize_t aout_output_show(struct device *dev,
639 				struct device_attribute *attr, char *buf)
640 {
641 	struct lm87_data *data = lm87_update_device(dev);
642 	return sprintf(buf, "%d\n", AOUT_FROM_REG(data->aout));
643 }
644 static ssize_t aout_output_store(struct device *dev,
645 				 struct device_attribute *attr,
646 				 const char *buf, size_t count)
647 {
648 	struct i2c_client *client = dev_get_drvdata(dev);
649 	struct lm87_data *data = i2c_get_clientdata(client);
650 	long val;
651 	int err;
652 
653 	err = kstrtol(buf, 10, &val);
654 	if (err)
655 		return err;
656 
657 	mutex_lock(&data->update_lock);
658 	data->aout = AOUT_TO_REG(val);
659 	lm87_write_value(client, LM87_REG_AOUT, data->aout);
660 	mutex_unlock(&data->update_lock);
661 	return count;
662 }
663 static DEVICE_ATTR_RW(aout_output);
664 
665 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
666 			  char *buf)
667 {
668 	struct lm87_data *data = lm87_update_device(dev);
669 	int bitnr = to_sensor_dev_attr(attr)->index;
670 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
671 }
672 static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0);
673 static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 1);
674 static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 2);
675 static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 3);
676 static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 8);
677 static SENSOR_DEVICE_ATTR_RO(in5_alarm, alarm, 9);
678 static SENSOR_DEVICE_ATTR_RO(in6_alarm, alarm, 6);
679 static SENSOR_DEVICE_ATTR_RO(in7_alarm, alarm, 7);
680 static SENSOR_DEVICE_ATTR_RO(temp1_alarm, alarm, 4);
681 static SENSOR_DEVICE_ATTR_RO(temp2_alarm, alarm, 5);
682 static SENSOR_DEVICE_ATTR_RO(temp3_alarm, alarm, 5);
683 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, alarm, 6);
684 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, alarm, 7);
685 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 14);
686 static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 15);
687 
688 /*
689  * Real code
690  */
691 
692 static struct attribute *lm87_attributes[] = {
693 	&sensor_dev_attr_in1_input.dev_attr.attr,
694 	&sensor_dev_attr_in1_min.dev_attr.attr,
695 	&sensor_dev_attr_in1_max.dev_attr.attr,
696 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
697 	&sensor_dev_attr_in2_input.dev_attr.attr,
698 	&sensor_dev_attr_in2_min.dev_attr.attr,
699 	&sensor_dev_attr_in2_max.dev_attr.attr,
700 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
701 	&sensor_dev_attr_in3_input.dev_attr.attr,
702 	&sensor_dev_attr_in3_min.dev_attr.attr,
703 	&sensor_dev_attr_in3_max.dev_attr.attr,
704 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
705 	&sensor_dev_attr_in4_input.dev_attr.attr,
706 	&sensor_dev_attr_in4_min.dev_attr.attr,
707 	&sensor_dev_attr_in4_max.dev_attr.attr,
708 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
709 
710 	&sensor_dev_attr_temp1_input.dev_attr.attr,
711 	&sensor_dev_attr_temp1_max.dev_attr.attr,
712 	&sensor_dev_attr_temp1_min.dev_attr.attr,
713 	&dev_attr_temp1_crit.attr,
714 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
715 	&sensor_dev_attr_temp2_input.dev_attr.attr,
716 	&sensor_dev_attr_temp2_max.dev_attr.attr,
717 	&sensor_dev_attr_temp2_min.dev_attr.attr,
718 	&dev_attr_temp2_crit.attr,
719 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
720 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
721 
722 	&dev_attr_alarms.attr,
723 	&dev_attr_aout_output.attr,
724 
725 	NULL
726 };
727 
728 static const struct attribute_group lm87_group = {
729 	.attrs = lm87_attributes,
730 };
731 
732 static struct attribute *lm87_attributes_in6[] = {
733 	&sensor_dev_attr_in6_input.dev_attr.attr,
734 	&sensor_dev_attr_in6_min.dev_attr.attr,
735 	&sensor_dev_attr_in6_max.dev_attr.attr,
736 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
737 	NULL
738 };
739 
740 static const struct attribute_group lm87_group_in6 = {
741 	.attrs = lm87_attributes_in6,
742 };
743 
744 static struct attribute *lm87_attributes_fan1[] = {
745 	&sensor_dev_attr_fan1_input.dev_attr.attr,
746 	&sensor_dev_attr_fan1_min.dev_attr.attr,
747 	&sensor_dev_attr_fan1_div.dev_attr.attr,
748 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
749 	NULL
750 };
751 
752 static const struct attribute_group lm87_group_fan1 = {
753 	.attrs = lm87_attributes_fan1,
754 };
755 
756 static struct attribute *lm87_attributes_in7[] = {
757 	&sensor_dev_attr_in7_input.dev_attr.attr,
758 	&sensor_dev_attr_in7_min.dev_attr.attr,
759 	&sensor_dev_attr_in7_max.dev_attr.attr,
760 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
761 	NULL
762 };
763 
764 static const struct attribute_group lm87_group_in7 = {
765 	.attrs = lm87_attributes_in7,
766 };
767 
768 static struct attribute *lm87_attributes_fan2[] = {
769 	&sensor_dev_attr_fan2_input.dev_attr.attr,
770 	&sensor_dev_attr_fan2_min.dev_attr.attr,
771 	&sensor_dev_attr_fan2_div.dev_attr.attr,
772 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
773 	NULL
774 };
775 
776 static const struct attribute_group lm87_group_fan2 = {
777 	.attrs = lm87_attributes_fan2,
778 };
779 
780 static struct attribute *lm87_attributes_temp3[] = {
781 	&sensor_dev_attr_temp3_input.dev_attr.attr,
782 	&sensor_dev_attr_temp3_max.dev_attr.attr,
783 	&sensor_dev_attr_temp3_min.dev_attr.attr,
784 	&dev_attr_temp3_crit.attr,
785 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
786 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
787 	NULL
788 };
789 
790 static const struct attribute_group lm87_group_temp3 = {
791 	.attrs = lm87_attributes_temp3,
792 };
793 
794 static struct attribute *lm87_attributes_in0_5[] = {
795 	&sensor_dev_attr_in0_input.dev_attr.attr,
796 	&sensor_dev_attr_in0_min.dev_attr.attr,
797 	&sensor_dev_attr_in0_max.dev_attr.attr,
798 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
799 	&sensor_dev_attr_in5_input.dev_attr.attr,
800 	&sensor_dev_attr_in5_min.dev_attr.attr,
801 	&sensor_dev_attr_in5_max.dev_attr.attr,
802 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
803 	NULL
804 };
805 
806 static const struct attribute_group lm87_group_in0_5 = {
807 	.attrs = lm87_attributes_in0_5,
808 };
809 
810 static struct attribute *lm87_attributes_vid[] = {
811 	&dev_attr_cpu0_vid.attr,
812 	&dev_attr_vrm.attr,
813 	NULL
814 };
815 
816 static const struct attribute_group lm87_group_vid = {
817 	.attrs = lm87_attributes_vid,
818 };
819 
820 /* Return 0 if detection is successful, -ENODEV otherwise */
821 static int lm87_detect(struct i2c_client *client, struct i2c_board_info *info)
822 {
823 	struct i2c_adapter *adapter = client->adapter;
824 	const char *name;
825 	u8 cid, rev;
826 
827 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
828 		return -ENODEV;
829 
830 	if (lm87_read_value(client, LM87_REG_CONFIG) & 0x80)
831 		return -ENODEV;
832 
833 	/* Now, we do the remaining detection. */
834 	cid = lm87_read_value(client, LM87_REG_COMPANY_ID);
835 	rev = lm87_read_value(client, LM87_REG_REVISION);
836 
837 	if (cid == 0x02			/* National Semiconductor */
838 	 && (rev >= 0x01 && rev <= 0x08))
839 		name = "lm87";
840 	else if (cid == 0x41		/* Analog Devices */
841 	      && (rev & 0xf0) == 0x10)
842 		name = "adm1024";
843 	else {
844 		dev_dbg(&adapter->dev, "LM87 detection failed at 0x%02x\n",
845 			client->addr);
846 		return -ENODEV;
847 	}
848 
849 	strlcpy(info->type, name, I2C_NAME_SIZE);
850 
851 	return 0;
852 }
853 
854 static void lm87_restore_config(void *arg)
855 {
856 	struct i2c_client *client = arg;
857 	struct lm87_data *data = i2c_get_clientdata(client);
858 
859 	lm87_write_value(client, LM87_REG_CONFIG, data->config);
860 }
861 
862 static int lm87_init_client(struct i2c_client *client)
863 {
864 	struct lm87_data *data = i2c_get_clientdata(client);
865 	int rc;
866 	struct device_node *of_node = client->dev.of_node;
867 	u8 val = 0;
868 	struct regulator *vcc = NULL;
869 
870 	if (of_node) {
871 		if (of_property_read_bool(of_node, "has-temp3"))
872 			val |= CHAN_TEMP3;
873 		if (of_property_read_bool(of_node, "has-in6"))
874 			val |= CHAN_NO_FAN(0);
875 		if (of_property_read_bool(of_node, "has-in7"))
876 			val |= CHAN_NO_FAN(1);
877 		vcc = devm_regulator_get_optional(&client->dev, "vcc");
878 		if (!IS_ERR(vcc)) {
879 			if (regulator_get_voltage(vcc) == 5000000)
880 				val |= CHAN_VCC_5V;
881 		}
882 		data->channel = val;
883 		lm87_write_value(client,
884 				LM87_REG_CHANNEL_MODE, data->channel);
885 	} else if (dev_get_platdata(&client->dev)) {
886 		data->channel = *(u8 *)dev_get_platdata(&client->dev);
887 		lm87_write_value(client,
888 				 LM87_REG_CHANNEL_MODE, data->channel);
889 	} else {
890 		data->channel = lm87_read_value(client, LM87_REG_CHANNEL_MODE);
891 	}
892 	data->config = lm87_read_value(client, LM87_REG_CONFIG) & 0x6F;
893 
894 	rc = devm_add_action(&client->dev, lm87_restore_config, client);
895 	if (rc)
896 		return rc;
897 
898 	if (!(data->config & 0x01)) {
899 		int i;
900 
901 		/* Limits are left uninitialized after power-up */
902 		for (i = 1; i < 6; i++) {
903 			lm87_write_value(client, LM87_REG_IN_MIN(i), 0x00);
904 			lm87_write_value(client, LM87_REG_IN_MAX(i), 0xFF);
905 		}
906 		for (i = 0; i < 2; i++) {
907 			lm87_write_value(client, LM87_REG_TEMP_HIGH[i], 0x7F);
908 			lm87_write_value(client, LM87_REG_TEMP_LOW[i], 0x00);
909 			lm87_write_value(client, LM87_REG_AIN_MIN(i), 0x00);
910 			lm87_write_value(client, LM87_REG_AIN_MAX(i), 0xFF);
911 		}
912 		if (data->channel & CHAN_TEMP3) {
913 			lm87_write_value(client, LM87_REG_TEMP_HIGH[2], 0x7F);
914 			lm87_write_value(client, LM87_REG_TEMP_LOW[2], 0x00);
915 		} else {
916 			lm87_write_value(client, LM87_REG_IN_MIN(0), 0x00);
917 			lm87_write_value(client, LM87_REG_IN_MAX(0), 0xFF);
918 		}
919 	}
920 
921 	/* Make sure Start is set and INT#_Clear is clear */
922 	if ((data->config & 0x09) != 0x01)
923 		lm87_write_value(client, LM87_REG_CONFIG,
924 				 (data->config & 0x77) | 0x01);
925 	return 0;
926 }
927 
928 static int lm87_probe(struct i2c_client *client, const struct i2c_device_id *id)
929 {
930 	struct lm87_data *data;
931 	struct device *hwmon_dev;
932 	int err;
933 	unsigned int group_tail = 0;
934 
935 	data = devm_kzalloc(&client->dev, sizeof(struct lm87_data), GFP_KERNEL);
936 	if (!data)
937 		return -ENOMEM;
938 
939 	i2c_set_clientdata(client, data);
940 	mutex_init(&data->update_lock);
941 
942 	/* Initialize the LM87 chip */
943 	err = lm87_init_client(client);
944 	if (err)
945 		return err;
946 
947 	data->in_scale[0] = 2500;
948 	data->in_scale[1] = 2700;
949 	data->in_scale[2] = (data->channel & CHAN_VCC_5V) ? 5000 : 3300;
950 	data->in_scale[3] = 5000;
951 	data->in_scale[4] = 12000;
952 	data->in_scale[5] = 2700;
953 	data->in_scale[6] = 1875;
954 	data->in_scale[7] = 1875;
955 
956 	/*
957 	 * Construct the list of attributes, the list depends on the
958 	 * configuration of the chip
959 	 */
960 	data->attr_groups[group_tail++] = &lm87_group;
961 	if (data->channel & CHAN_NO_FAN(0))
962 		data->attr_groups[group_tail++] = &lm87_group_in6;
963 	else
964 		data->attr_groups[group_tail++] = &lm87_group_fan1;
965 
966 	if (data->channel & CHAN_NO_FAN(1))
967 		data->attr_groups[group_tail++] = &lm87_group_in7;
968 	else
969 		data->attr_groups[group_tail++] = &lm87_group_fan2;
970 
971 	if (data->channel & CHAN_TEMP3)
972 		data->attr_groups[group_tail++] = &lm87_group_temp3;
973 	else
974 		data->attr_groups[group_tail++] = &lm87_group_in0_5;
975 
976 	if (!(data->channel & CHAN_NO_VID)) {
977 		data->vrm = vid_which_vrm();
978 		data->attr_groups[group_tail++] = &lm87_group_vid;
979 	}
980 
981 	hwmon_dev = devm_hwmon_device_register_with_groups(
982 	    &client->dev, client->name, client, data->attr_groups);
983 	return PTR_ERR_OR_ZERO(hwmon_dev);
984 }
985 
986 /*
987  * Driver data (common to all clients)
988  */
989 
990 static const struct i2c_device_id lm87_id[] = {
991 	{ "lm87", 0 },
992 	{ "adm1024", 0 },
993 	{ }
994 };
995 MODULE_DEVICE_TABLE(i2c, lm87_id);
996 
997 static const struct of_device_id lm87_of_match[] = {
998 	{ .compatible = "ti,lm87" },
999 	{ .compatible = "adi,adm1024" },
1000 	{ },
1001 };
1002 MODULE_DEVICE_TABLE(of, lm87_of_match);
1003 
1004 static struct i2c_driver lm87_driver = {
1005 	.class		= I2C_CLASS_HWMON,
1006 	.driver = {
1007 		.name	= "lm87",
1008 		.of_match_table = lm87_of_match,
1009 	},
1010 	.probe		= lm87_probe,
1011 	.id_table	= lm87_id,
1012 	.detect		= lm87_detect,
1013 	.address_list	= normal_i2c,
1014 };
1015 
1016 module_i2c_driver(lm87_driver);
1017 
1018 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de> and others");
1019 MODULE_DESCRIPTION("LM87 driver");
1020 MODULE_LICENSE("GPL");
1021