xref: /openbmc/linux/drivers/hwmon/lm80.c (revision 842ed298)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * lm80.c - From lm_sensors, Linux kernel modules for hardware
4  *	    monitoring
5  * Copyright (C) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
6  *			     and Philip Edelbrock <phil@netroedge.com>
7  *
8  * Ported to Linux 2.6 by Tiago Sousa <mirage@kaotik.org>
9  */
10 
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/slab.h>
14 #include <linux/jiffies.h>
15 #include <linux/i2c.h>
16 #include <linux/hwmon.h>
17 #include <linux/hwmon-sysfs.h>
18 #include <linux/err.h>
19 #include <linux/mutex.h>
20 
21 /* Addresses to scan */
22 static const unsigned short normal_i2c[] = { 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
23 						0x2e, 0x2f, I2C_CLIENT_END };
24 
25 /* Many LM80 constants specified below */
26 
27 /* The LM80 registers */
28 #define LM80_REG_IN_MAX(nr)		(0x2a + (nr) * 2)
29 #define LM80_REG_IN_MIN(nr)		(0x2b + (nr) * 2)
30 #define LM80_REG_IN(nr)			(0x20 + (nr))
31 
32 #define LM80_REG_FAN1			0x28
33 #define LM80_REG_FAN2			0x29
34 #define LM80_REG_FAN_MIN(nr)		(0x3b + (nr))
35 
36 #define LM80_REG_TEMP			0x27
37 #define LM80_REG_TEMP_HOT_MAX		0x38
38 #define LM80_REG_TEMP_HOT_HYST		0x39
39 #define LM80_REG_TEMP_OS_MAX		0x3a
40 #define LM80_REG_TEMP_OS_HYST		0x3b
41 
42 #define LM80_REG_CONFIG			0x00
43 #define LM80_REG_ALARM1			0x01
44 #define LM80_REG_ALARM2			0x02
45 #define LM80_REG_MASK1			0x03
46 #define LM80_REG_MASK2			0x04
47 #define LM80_REG_FANDIV			0x05
48 #define LM80_REG_RES			0x06
49 
50 #define LM96080_REG_CONV_RATE		0x07
51 #define LM96080_REG_MAN_ID		0x3e
52 #define LM96080_REG_DEV_ID		0x3f
53 
54 
55 /*
56  * Conversions. Rounding and limit checking is only done on the TO_REG
57  * variants. Note that you should be a bit careful with which arguments
58  * these macros are called: arguments may be evaluated more than once.
59  * Fixing this is just not worth it.
60  */
61 
62 #define IN_TO_REG(val)		(clamp_val(((val) + 5) / 10, 0, 255))
63 #define IN_FROM_REG(val)	((val) * 10)
64 
65 static inline unsigned char FAN_TO_REG(unsigned rpm, unsigned div)
66 {
67 	if (rpm == 0)
68 		return 255;
69 	rpm = clamp_val(rpm, 1, 1000000);
70 	return clamp_val((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
71 }
72 
73 #define FAN_FROM_REG(val, div)	((val) == 0 ? -1 : \
74 				(val) == 255 ? 0 : 1350000/((div) * (val)))
75 
76 #define TEMP_FROM_REG(reg)	((reg) * 125 / 32)
77 #define TEMP_TO_REG(temp)	(DIV_ROUND_CLOSEST(clamp_val((temp), \
78 					-128000, 127000), 1000) << 8)
79 
80 #define DIV_FROM_REG(val)		(1 << (val))
81 
82 enum temp_index {
83 	t_input = 0,
84 	t_hot_max,
85 	t_hot_hyst,
86 	t_os_max,
87 	t_os_hyst,
88 	t_num_temp
89 };
90 
91 static const u8 temp_regs[t_num_temp] = {
92 	[t_input] = LM80_REG_TEMP,
93 	[t_hot_max] = LM80_REG_TEMP_HOT_MAX,
94 	[t_hot_hyst] = LM80_REG_TEMP_HOT_HYST,
95 	[t_os_max] = LM80_REG_TEMP_OS_MAX,
96 	[t_os_hyst] = LM80_REG_TEMP_OS_HYST,
97 };
98 
99 enum in_index {
100 	i_input = 0,
101 	i_max,
102 	i_min,
103 	i_num_in
104 };
105 
106 enum fan_index {
107 	f_input,
108 	f_min,
109 	f_num_fan
110 };
111 
112 /*
113  * Client data (each client gets its own)
114  */
115 
116 struct lm80_data {
117 	struct i2c_client *client;
118 	struct mutex update_lock;
119 	char error;		/* !=0 if error occurred during last update */
120 	char valid;		/* !=0 if following fields are valid */
121 	unsigned long last_updated;	/* In jiffies */
122 
123 	u8 in[i_num_in][7];	/* Register value, 1st index is enum in_index */
124 	u8 fan[f_num_fan][2];	/* Register value, 1st index enum fan_index */
125 	u8 fan_div[2];		/* Register encoding, shifted right */
126 	s16 temp[t_num_temp];	/* Register values, normalized to 16 bit */
127 	u16 alarms;		/* Register encoding, combined */
128 };
129 
130 static int lm80_read_value(struct i2c_client *client, u8 reg)
131 {
132 	return i2c_smbus_read_byte_data(client, reg);
133 }
134 
135 static int lm80_write_value(struct i2c_client *client, u8 reg, u8 value)
136 {
137 	return i2c_smbus_write_byte_data(client, reg, value);
138 }
139 
140 /* Called when we have found a new LM80 and after read errors */
141 static void lm80_init_client(struct i2c_client *client)
142 {
143 	/*
144 	 * Reset all except Watchdog values and last conversion values
145 	 * This sets fan-divs to 2, among others. This makes most other
146 	 * initializations unnecessary
147 	 */
148 	lm80_write_value(client, LM80_REG_CONFIG, 0x80);
149 	/* Set 11-bit temperature resolution */
150 	lm80_write_value(client, LM80_REG_RES, 0x08);
151 
152 	/* Start monitoring */
153 	lm80_write_value(client, LM80_REG_CONFIG, 0x01);
154 }
155 
156 static struct lm80_data *lm80_update_device(struct device *dev)
157 {
158 	struct lm80_data *data = dev_get_drvdata(dev);
159 	struct i2c_client *client = data->client;
160 	int i;
161 	int rv;
162 	int prev_rv;
163 	struct lm80_data *ret = data;
164 
165 	mutex_lock(&data->update_lock);
166 
167 	if (data->error)
168 		lm80_init_client(client);
169 
170 	if (time_after(jiffies, data->last_updated + 2 * HZ) || !data->valid) {
171 		dev_dbg(dev, "Starting lm80 update\n");
172 		for (i = 0; i <= 6; i++) {
173 			rv = lm80_read_value(client, LM80_REG_IN(i));
174 			if (rv < 0)
175 				goto abort;
176 			data->in[i_input][i] = rv;
177 
178 			rv = lm80_read_value(client, LM80_REG_IN_MIN(i));
179 			if (rv < 0)
180 				goto abort;
181 			data->in[i_min][i] = rv;
182 
183 			rv = lm80_read_value(client, LM80_REG_IN_MAX(i));
184 			if (rv < 0)
185 				goto abort;
186 			data->in[i_max][i] = rv;
187 		}
188 
189 		rv = lm80_read_value(client, LM80_REG_FAN1);
190 		if (rv < 0)
191 			goto abort;
192 		data->fan[f_input][0] = rv;
193 
194 		rv = lm80_read_value(client, LM80_REG_FAN_MIN(1));
195 		if (rv < 0)
196 			goto abort;
197 		data->fan[f_min][0] = rv;
198 
199 		rv = lm80_read_value(client, LM80_REG_FAN2);
200 		if (rv < 0)
201 			goto abort;
202 		data->fan[f_input][1] = rv;
203 
204 		rv = lm80_read_value(client, LM80_REG_FAN_MIN(2));
205 		if (rv < 0)
206 			goto abort;
207 		data->fan[f_min][1] = rv;
208 
209 		prev_rv = rv = lm80_read_value(client, LM80_REG_TEMP);
210 		if (rv < 0)
211 			goto abort;
212 		rv = lm80_read_value(client, LM80_REG_RES);
213 		if (rv < 0)
214 			goto abort;
215 		data->temp[t_input] = (prev_rv << 8) | (rv & 0xf0);
216 
217 		for (i = t_input + 1; i < t_num_temp; i++) {
218 			rv = lm80_read_value(client, temp_regs[i]);
219 			if (rv < 0)
220 				goto abort;
221 			data->temp[i] = rv << 8;
222 		}
223 
224 		rv = lm80_read_value(client, LM80_REG_FANDIV);
225 		if (rv < 0)
226 			goto abort;
227 		data->fan_div[0] = (rv >> 2) & 0x03;
228 		data->fan_div[1] = (rv >> 4) & 0x03;
229 
230 		prev_rv = rv = lm80_read_value(client, LM80_REG_ALARM1);
231 		if (rv < 0)
232 			goto abort;
233 		rv = lm80_read_value(client, LM80_REG_ALARM2);
234 		if (rv < 0)
235 			goto abort;
236 		data->alarms = prev_rv + (rv << 8);
237 
238 		data->last_updated = jiffies;
239 		data->valid = 1;
240 		data->error = 0;
241 	}
242 	goto done;
243 
244 abort:
245 	ret = ERR_PTR(rv);
246 	data->valid = 0;
247 	data->error = 1;
248 
249 done:
250 	mutex_unlock(&data->update_lock);
251 
252 	return ret;
253 }
254 
255 /*
256  * Sysfs stuff
257  */
258 
259 static ssize_t in_show(struct device *dev, struct device_attribute *attr,
260 		       char *buf)
261 {
262 	struct lm80_data *data = lm80_update_device(dev);
263 	int index = to_sensor_dev_attr_2(attr)->index;
264 	int nr = to_sensor_dev_attr_2(attr)->nr;
265 
266 	if (IS_ERR(data))
267 		return PTR_ERR(data);
268 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[nr][index]));
269 }
270 
271 static ssize_t in_store(struct device *dev, struct device_attribute *attr,
272 			const char *buf, size_t count)
273 {
274 	struct lm80_data *data = dev_get_drvdata(dev);
275 	struct i2c_client *client = data->client;
276 	int index = to_sensor_dev_attr_2(attr)->index;
277 	int nr = to_sensor_dev_attr_2(attr)->nr;
278 	long val;
279 	u8 reg;
280 	int err = kstrtol(buf, 10, &val);
281 	if (err < 0)
282 		return err;
283 
284 	reg = nr == i_min ? LM80_REG_IN_MIN(index) : LM80_REG_IN_MAX(index);
285 
286 	mutex_lock(&data->update_lock);
287 	data->in[nr][index] = IN_TO_REG(val);
288 	lm80_write_value(client, reg, data->in[nr][index]);
289 	mutex_unlock(&data->update_lock);
290 	return count;
291 }
292 
293 static ssize_t fan_show(struct device *dev, struct device_attribute *attr,
294 			char *buf)
295 {
296 	int index = to_sensor_dev_attr_2(attr)->index;
297 	int nr = to_sensor_dev_attr_2(attr)->nr;
298 	struct lm80_data *data = lm80_update_device(dev);
299 	if (IS_ERR(data))
300 		return PTR_ERR(data);
301 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr][index],
302 		       DIV_FROM_REG(data->fan_div[index])));
303 }
304 
305 static ssize_t fan_div_show(struct device *dev, struct device_attribute *attr,
306 			    char *buf)
307 {
308 	int nr = to_sensor_dev_attr(attr)->index;
309 	struct lm80_data *data = lm80_update_device(dev);
310 	if (IS_ERR(data))
311 		return PTR_ERR(data);
312 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
313 }
314 
315 static ssize_t fan_store(struct device *dev, struct device_attribute *attr,
316 			 const char *buf, size_t count)
317 {
318 	int index = to_sensor_dev_attr_2(attr)->index;
319 	int nr = to_sensor_dev_attr_2(attr)->nr;
320 	struct lm80_data *data = dev_get_drvdata(dev);
321 	struct i2c_client *client = data->client;
322 	unsigned long val;
323 	int err = kstrtoul(buf, 10, &val);
324 	if (err < 0)
325 		return err;
326 
327 	mutex_lock(&data->update_lock);
328 	data->fan[nr][index] = FAN_TO_REG(val,
329 					  DIV_FROM_REG(data->fan_div[index]));
330 	lm80_write_value(client, LM80_REG_FAN_MIN(index + 1),
331 			 data->fan[nr][index]);
332 	mutex_unlock(&data->update_lock);
333 	return count;
334 }
335 
336 /*
337  * Note: we save and restore the fan minimum here, because its value is
338  * determined in part by the fan divisor.  This follows the principle of
339  * least surprise; the user doesn't expect the fan minimum to change just
340  * because the divisor changed.
341  */
342 static ssize_t fan_div_store(struct device *dev,
343 			     struct device_attribute *attr, const char *buf,
344 			     size_t count)
345 {
346 	int nr = to_sensor_dev_attr(attr)->index;
347 	struct lm80_data *data = dev_get_drvdata(dev);
348 	struct i2c_client *client = data->client;
349 	unsigned long min, val;
350 	u8 reg;
351 	int rv;
352 
353 	rv = kstrtoul(buf, 10, &val);
354 	if (rv < 0)
355 		return rv;
356 
357 	/* Save fan_min */
358 	mutex_lock(&data->update_lock);
359 	min = FAN_FROM_REG(data->fan[f_min][nr],
360 			   DIV_FROM_REG(data->fan_div[nr]));
361 
362 	switch (val) {
363 	case 1:
364 		data->fan_div[nr] = 0;
365 		break;
366 	case 2:
367 		data->fan_div[nr] = 1;
368 		break;
369 	case 4:
370 		data->fan_div[nr] = 2;
371 		break;
372 	case 8:
373 		data->fan_div[nr] = 3;
374 		break;
375 	default:
376 		dev_err(dev,
377 			"fan_div value %ld not supported. Choose one of 1, 2, 4 or 8!\n",
378 			val);
379 		mutex_unlock(&data->update_lock);
380 		return -EINVAL;
381 	}
382 
383 	rv = lm80_read_value(client, LM80_REG_FANDIV);
384 	if (rv < 0) {
385 		mutex_unlock(&data->update_lock);
386 		return rv;
387 	}
388 	reg = (rv & ~(3 << (2 * (nr + 1))))
389 	    | (data->fan_div[nr] << (2 * (nr + 1)));
390 	lm80_write_value(client, LM80_REG_FANDIV, reg);
391 
392 	/* Restore fan_min */
393 	data->fan[f_min][nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
394 	lm80_write_value(client, LM80_REG_FAN_MIN(nr + 1),
395 			 data->fan[f_min][nr]);
396 	mutex_unlock(&data->update_lock);
397 
398 	return count;
399 }
400 
401 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
402 			 char *buf)
403 {
404 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
405 	struct lm80_data *data = lm80_update_device(dev);
406 	if (IS_ERR(data))
407 		return PTR_ERR(data);
408 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
409 }
410 
411 static ssize_t temp_store(struct device *dev,
412 			  struct device_attribute *devattr, const char *buf,
413 			  size_t count)
414 {
415 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
416 	struct lm80_data *data = dev_get_drvdata(dev);
417 	struct i2c_client *client = data->client;
418 	int nr = attr->index;
419 	long val;
420 	int err = kstrtol(buf, 10, &val);
421 	if (err < 0)
422 		return err;
423 
424 	mutex_lock(&data->update_lock);
425 	data->temp[nr] = TEMP_TO_REG(val);
426 	lm80_write_value(client, temp_regs[nr], data->temp[nr] >> 8);
427 	mutex_unlock(&data->update_lock);
428 	return count;
429 }
430 
431 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
432 			   char *buf)
433 {
434 	struct lm80_data *data = lm80_update_device(dev);
435 	if (IS_ERR(data))
436 		return PTR_ERR(data);
437 	return sprintf(buf, "%u\n", data->alarms);
438 }
439 
440 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
441 			  char *buf)
442 {
443 	int bitnr = to_sensor_dev_attr(attr)->index;
444 	struct lm80_data *data = lm80_update_device(dev);
445 	if (IS_ERR(data))
446 		return PTR_ERR(data);
447 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
448 }
449 
450 static SENSOR_DEVICE_ATTR_2_RW(in0_min, in, i_min, 0);
451 static SENSOR_DEVICE_ATTR_2_RW(in1_min, in, i_min, 1);
452 static SENSOR_DEVICE_ATTR_2_RW(in2_min, in, i_min, 2);
453 static SENSOR_DEVICE_ATTR_2_RW(in3_min, in, i_min, 3);
454 static SENSOR_DEVICE_ATTR_2_RW(in4_min, in, i_min, 4);
455 static SENSOR_DEVICE_ATTR_2_RW(in5_min, in, i_min, 5);
456 static SENSOR_DEVICE_ATTR_2_RW(in6_min, in, i_min, 6);
457 static SENSOR_DEVICE_ATTR_2_RW(in0_max, in, i_max, 0);
458 static SENSOR_DEVICE_ATTR_2_RW(in1_max, in, i_max, 1);
459 static SENSOR_DEVICE_ATTR_2_RW(in2_max, in, i_max, 2);
460 static SENSOR_DEVICE_ATTR_2_RW(in3_max, in, i_max, 3);
461 static SENSOR_DEVICE_ATTR_2_RW(in4_max, in, i_max, 4);
462 static SENSOR_DEVICE_ATTR_2_RW(in5_max, in, i_max, 5);
463 static SENSOR_DEVICE_ATTR_2_RW(in6_max, in, i_max, 6);
464 static SENSOR_DEVICE_ATTR_2_RO(in0_input, in, i_input, 0);
465 static SENSOR_DEVICE_ATTR_2_RO(in1_input, in, i_input, 1);
466 static SENSOR_DEVICE_ATTR_2_RO(in2_input, in, i_input, 2);
467 static SENSOR_DEVICE_ATTR_2_RO(in3_input, in, i_input, 3);
468 static SENSOR_DEVICE_ATTR_2_RO(in4_input, in, i_input, 4);
469 static SENSOR_DEVICE_ATTR_2_RO(in5_input, in, i_input, 5);
470 static SENSOR_DEVICE_ATTR_2_RO(in6_input, in, i_input, 6);
471 static SENSOR_DEVICE_ATTR_2_RW(fan1_min, fan, f_min, 0);
472 static SENSOR_DEVICE_ATTR_2_RW(fan2_min, fan, f_min, 1);
473 static SENSOR_DEVICE_ATTR_2_RO(fan1_input, fan, f_input, 0);
474 static SENSOR_DEVICE_ATTR_2_RO(fan2_input, fan, f_input, 1);
475 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
476 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
477 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, t_input);
478 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, t_hot_max);
479 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, temp, t_hot_hyst);
480 static SENSOR_DEVICE_ATTR_RW(temp1_crit, temp, t_os_max);
481 static SENSOR_DEVICE_ATTR_RW(temp1_crit_hyst, temp, t_os_hyst);
482 static DEVICE_ATTR_RO(alarms);
483 static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0);
484 static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 1);
485 static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 2);
486 static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 3);
487 static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 4);
488 static SENSOR_DEVICE_ATTR_RO(in5_alarm, alarm, 5);
489 static SENSOR_DEVICE_ATTR_RO(in6_alarm, alarm, 6);
490 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, alarm, 10);
491 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, alarm, 11);
492 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 8);
493 static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 13);
494 
495 /*
496  * Real code
497  */
498 
499 static struct attribute *lm80_attrs[] = {
500 	&sensor_dev_attr_in0_min.dev_attr.attr,
501 	&sensor_dev_attr_in1_min.dev_attr.attr,
502 	&sensor_dev_attr_in2_min.dev_attr.attr,
503 	&sensor_dev_attr_in3_min.dev_attr.attr,
504 	&sensor_dev_attr_in4_min.dev_attr.attr,
505 	&sensor_dev_attr_in5_min.dev_attr.attr,
506 	&sensor_dev_attr_in6_min.dev_attr.attr,
507 	&sensor_dev_attr_in0_max.dev_attr.attr,
508 	&sensor_dev_attr_in1_max.dev_attr.attr,
509 	&sensor_dev_attr_in2_max.dev_attr.attr,
510 	&sensor_dev_attr_in3_max.dev_attr.attr,
511 	&sensor_dev_attr_in4_max.dev_attr.attr,
512 	&sensor_dev_attr_in5_max.dev_attr.attr,
513 	&sensor_dev_attr_in6_max.dev_attr.attr,
514 	&sensor_dev_attr_in0_input.dev_attr.attr,
515 	&sensor_dev_attr_in1_input.dev_attr.attr,
516 	&sensor_dev_attr_in2_input.dev_attr.attr,
517 	&sensor_dev_attr_in3_input.dev_attr.attr,
518 	&sensor_dev_attr_in4_input.dev_attr.attr,
519 	&sensor_dev_attr_in5_input.dev_attr.attr,
520 	&sensor_dev_attr_in6_input.dev_attr.attr,
521 	&sensor_dev_attr_fan1_min.dev_attr.attr,
522 	&sensor_dev_attr_fan2_min.dev_attr.attr,
523 	&sensor_dev_attr_fan1_input.dev_attr.attr,
524 	&sensor_dev_attr_fan2_input.dev_attr.attr,
525 	&sensor_dev_attr_fan1_div.dev_attr.attr,
526 	&sensor_dev_attr_fan2_div.dev_attr.attr,
527 	&sensor_dev_attr_temp1_input.dev_attr.attr,
528 	&sensor_dev_attr_temp1_max.dev_attr.attr,
529 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
530 	&sensor_dev_attr_temp1_crit.dev_attr.attr,
531 	&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
532 	&dev_attr_alarms.attr,
533 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
534 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
535 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
536 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
537 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
538 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
539 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
540 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
541 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
542 	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
543 	&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
544 	NULL
545 };
546 ATTRIBUTE_GROUPS(lm80);
547 
548 /* Return 0 if detection is successful, -ENODEV otherwise */
549 static int lm80_detect(struct i2c_client *client, struct i2c_board_info *info)
550 {
551 	struct i2c_adapter *adapter = client->adapter;
552 	int i, cur, man_id, dev_id;
553 	const char *name = NULL;
554 
555 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
556 		return -ENODEV;
557 
558 	/* First check for unused bits, common to both chip types */
559 	if ((lm80_read_value(client, LM80_REG_ALARM2) & 0xc0)
560 	 || (lm80_read_value(client, LM80_REG_CONFIG) & 0x80))
561 		return -ENODEV;
562 
563 	/*
564 	 * The LM96080 has manufacturer and stepping/die rev registers so we
565 	 * can just check that. The LM80 does not have such registers so we
566 	 * have to use a more expensive trick.
567 	 */
568 	man_id = lm80_read_value(client, LM96080_REG_MAN_ID);
569 	dev_id = lm80_read_value(client, LM96080_REG_DEV_ID);
570 	if (man_id == 0x01 && dev_id == 0x08) {
571 		/* Check more unused bits for confirmation */
572 		if (lm80_read_value(client, LM96080_REG_CONV_RATE) & 0xfe)
573 			return -ENODEV;
574 
575 		name = "lm96080";
576 	} else {
577 		/* Check 6-bit addressing */
578 		for (i = 0x2a; i <= 0x3d; i++) {
579 			cur = i2c_smbus_read_byte_data(client, i);
580 			if ((i2c_smbus_read_byte_data(client, i + 0x40) != cur)
581 			 || (i2c_smbus_read_byte_data(client, i + 0x80) != cur)
582 			 || (i2c_smbus_read_byte_data(client, i + 0xc0) != cur))
583 				return -ENODEV;
584 		}
585 
586 		name = "lm80";
587 	}
588 
589 	strlcpy(info->type, name, I2C_NAME_SIZE);
590 
591 	return 0;
592 }
593 
594 static int lm80_probe(struct i2c_client *client)
595 {
596 	struct device *dev = &client->dev;
597 	struct device *hwmon_dev;
598 	struct lm80_data *data;
599 	int rv;
600 
601 	data = devm_kzalloc(dev, sizeof(struct lm80_data), GFP_KERNEL);
602 	if (!data)
603 		return -ENOMEM;
604 
605 	data->client = client;
606 	mutex_init(&data->update_lock);
607 
608 	/* Initialize the LM80 chip */
609 	lm80_init_client(client);
610 
611 	/* A few vars need to be filled upon startup */
612 	rv = lm80_read_value(client, LM80_REG_FAN_MIN(1));
613 	if (rv < 0)
614 		return rv;
615 	data->fan[f_min][0] = rv;
616 	rv = lm80_read_value(client, LM80_REG_FAN_MIN(2));
617 	if (rv < 0)
618 		return rv;
619 	data->fan[f_min][1] = rv;
620 
621 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
622 							   data, lm80_groups);
623 
624 	return PTR_ERR_OR_ZERO(hwmon_dev);
625 }
626 
627 /*
628  * Driver data (common to all clients)
629  */
630 
631 static const struct i2c_device_id lm80_id[] = {
632 	{ "lm80", 0 },
633 	{ "lm96080", 1 },
634 	{ }
635 };
636 MODULE_DEVICE_TABLE(i2c, lm80_id);
637 
638 static struct i2c_driver lm80_driver = {
639 	.class		= I2C_CLASS_HWMON,
640 	.driver = {
641 		.name	= "lm80",
642 	},
643 	.probe_new	= lm80_probe,
644 	.id_table	= lm80_id,
645 	.detect		= lm80_detect,
646 	.address_list	= normal_i2c,
647 };
648 
649 module_i2c_driver(lm80_driver);
650 
651 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
652 	"Philip Edelbrock <phil@netroedge.com>");
653 MODULE_DESCRIPTION("LM80 driver");
654 MODULE_LICENSE("GPL");
655