xref: /openbmc/linux/drivers/hwmon/smsc47m192.c (revision 82e6fdd6)
1 /*
2  * smsc47m192.c - Support for hardware monitoring block of
3  *		  SMSC LPC47M192 and compatible Super I/O chips
4  *
5  * Copyright (C) 2006  Hartmut Rick <linux@rick.claranet.de>
6  *
7  * Derived from lm78.c and other chip drivers.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23 
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/slab.h>
27 #include <linux/jiffies.h>
28 #include <linux/i2c.h>
29 #include <linux/hwmon.h>
30 #include <linux/hwmon-sysfs.h>
31 #include <linux/hwmon-vid.h>
32 #include <linux/err.h>
33 #include <linux/sysfs.h>
34 #include <linux/mutex.h>
35 
36 /* Addresses to scan */
37 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, I2C_CLIENT_END };
38 
39 /* SMSC47M192 registers */
40 #define SMSC47M192_REG_IN(nr)		((nr) < 6 ? (0x20 + (nr)) : \
41 					(0x50 + (nr) - 6))
42 #define SMSC47M192_REG_IN_MAX(nr)	((nr) < 6 ? (0x2b + (nr) * 2) : \
43 					(0x54 + (((nr) - 6) * 2)))
44 #define SMSC47M192_REG_IN_MIN(nr)	((nr) < 6 ? (0x2c + (nr) * 2) : \
45 					(0x55 + (((nr) - 6) * 2)))
46 static u8 SMSC47M192_REG_TEMP[3] =	{ 0x27, 0x26, 0x52 };
47 static u8 SMSC47M192_REG_TEMP_MAX[3] =	{ 0x39, 0x37, 0x58 };
48 static u8 SMSC47M192_REG_TEMP_MIN[3] =	{ 0x3A, 0x38, 0x59 };
49 #define SMSC47M192_REG_TEMP_OFFSET(nr)	((nr) == 2 ? 0x1e : 0x1f)
50 #define SMSC47M192_REG_ALARM1		0x41
51 #define SMSC47M192_REG_ALARM2		0x42
52 #define SMSC47M192_REG_VID		0x47
53 #define SMSC47M192_REG_VID4		0x49
54 #define SMSC47M192_REG_CONFIG		0x40
55 #define SMSC47M192_REG_SFR		0x4f
56 #define SMSC47M192_REG_COMPANY_ID	0x3e
57 #define SMSC47M192_REG_VERSION		0x3f
58 
59 /* generalised scaling with integer rounding */
60 static inline int SCALE(long val, int mul, int div)
61 {
62 	if (val < 0)
63 		return (val * mul - div / 2) / div;
64 	else
65 		return (val * mul + div / 2) / div;
66 }
67 
68 /* Conversions */
69 
70 /* smsc47m192 internally scales voltage measurements */
71 static const u16 nom_mv[] = { 2500, 2250, 3300, 5000, 12000, 3300, 1500, 1800 };
72 
73 static inline unsigned int IN_FROM_REG(u8 reg, int n)
74 {
75 	return SCALE(reg, nom_mv[n], 192);
76 }
77 
78 static inline u8 IN_TO_REG(unsigned long val, int n)
79 {
80 	val = clamp_val(val, 0, nom_mv[n] * 255 / 192);
81 	return SCALE(val, 192, nom_mv[n]);
82 }
83 
84 /*
85  * TEMP: 0.001 degC units (-128C to +127C)
86  * REG: 1C/bit, two's complement
87  */
88 static inline s8 TEMP_TO_REG(long val)
89 {
90 	return SCALE(clamp_val(val, -128000, 127000), 1, 1000);
91 }
92 
93 static inline int TEMP_FROM_REG(s8 val)
94 {
95 	return val * 1000;
96 }
97 
98 struct smsc47m192_data {
99 	struct i2c_client *client;
100 	const struct attribute_group *groups[3];
101 	struct mutex update_lock;
102 	char valid;		/* !=0 if following fields are valid */
103 	unsigned long last_updated;	/* In jiffies */
104 
105 	u8 in[8];		/* Register value */
106 	u8 in_max[8];		/* Register value */
107 	u8 in_min[8];		/* Register value */
108 	s8 temp[3];		/* Register value */
109 	s8 temp_max[3];		/* Register value */
110 	s8 temp_min[3];		/* Register value */
111 	s8 temp_offset[3];	/* Register value */
112 	u16 alarms;		/* Register encoding, combined */
113 	u8 vid;			/* Register encoding, combined */
114 	u8 vrm;
115 };
116 
117 static struct smsc47m192_data *smsc47m192_update_device(struct device *dev)
118 {
119 	struct smsc47m192_data *data = dev_get_drvdata(dev);
120 	struct i2c_client *client = data->client;
121 	int i, config;
122 
123 	mutex_lock(&data->update_lock);
124 
125 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
126 	 || !data->valid) {
127 		u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
128 
129 		dev_dbg(&client->dev, "Starting smsc47m192 update\n");
130 
131 		for (i = 0; i <= 7; i++) {
132 			data->in[i] = i2c_smbus_read_byte_data(client,
133 						SMSC47M192_REG_IN(i));
134 			data->in_min[i] = i2c_smbus_read_byte_data(client,
135 						SMSC47M192_REG_IN_MIN(i));
136 			data->in_max[i] = i2c_smbus_read_byte_data(client,
137 						SMSC47M192_REG_IN_MAX(i));
138 		}
139 		for (i = 0; i < 3; i++) {
140 			data->temp[i] = i2c_smbus_read_byte_data(client,
141 						SMSC47M192_REG_TEMP[i]);
142 			data->temp_max[i] = i2c_smbus_read_byte_data(client,
143 						SMSC47M192_REG_TEMP_MAX[i]);
144 			data->temp_min[i] = i2c_smbus_read_byte_data(client,
145 						SMSC47M192_REG_TEMP_MIN[i]);
146 		}
147 		for (i = 1; i < 3; i++)
148 			data->temp_offset[i] = i2c_smbus_read_byte_data(client,
149 						SMSC47M192_REG_TEMP_OFFSET(i));
150 		/*
151 		 * first offset is temp_offset[0] if SFR bit 4 is set,
152 		 * temp_offset[1] otherwise
153 		 */
154 		if (sfr & 0x10) {
155 			data->temp_offset[0] = data->temp_offset[1];
156 			data->temp_offset[1] = 0;
157 		} else
158 			data->temp_offset[0] = 0;
159 
160 		data->vid = i2c_smbus_read_byte_data(client, SMSC47M192_REG_VID)
161 			    & 0x0f;
162 		config = i2c_smbus_read_byte_data(client,
163 						  SMSC47M192_REG_CONFIG);
164 		if (config & 0x20)
165 			data->vid |= (i2c_smbus_read_byte_data(client,
166 					SMSC47M192_REG_VID4) & 0x01) << 4;
167 		data->alarms = i2c_smbus_read_byte_data(client,
168 						SMSC47M192_REG_ALARM1) |
169 			       (i2c_smbus_read_byte_data(client,
170 						SMSC47M192_REG_ALARM2) << 8);
171 
172 		data->last_updated = jiffies;
173 		data->valid = 1;
174 	}
175 
176 	mutex_unlock(&data->update_lock);
177 
178 	return data;
179 }
180 
181 /* Voltages */
182 static ssize_t show_in(struct device *dev, struct device_attribute *attr,
183 		char *buf)
184 {
185 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
186 	int nr = sensor_attr->index;
187 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
188 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[nr], nr));
189 }
190 
191 static ssize_t show_in_min(struct device *dev, struct device_attribute *attr,
192 		char *buf)
193 {
194 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
195 	int nr = sensor_attr->index;
196 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
197 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[nr], nr));
198 }
199 
200 static ssize_t show_in_max(struct device *dev, struct device_attribute *attr,
201 		char *buf)
202 {
203 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
204 	int nr = sensor_attr->index;
205 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
206 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[nr], nr));
207 }
208 
209 static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
210 		const char *buf, size_t count)
211 {
212 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
213 	int nr = sensor_attr->index;
214 	struct smsc47m192_data *data = dev_get_drvdata(dev);
215 	struct i2c_client *client = data->client;
216 	unsigned long val;
217 	int err;
218 
219 	err = kstrtoul(buf, 10, &val);
220 	if (err)
221 		return err;
222 
223 	mutex_lock(&data->update_lock);
224 	data->in_min[nr] = IN_TO_REG(val, nr);
225 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MIN(nr),
226 							data->in_min[nr]);
227 	mutex_unlock(&data->update_lock);
228 	return count;
229 }
230 
231 static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
232 		const char *buf, size_t count)
233 {
234 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
235 	int nr = sensor_attr->index;
236 	struct smsc47m192_data *data = dev_get_drvdata(dev);
237 	struct i2c_client *client = data->client;
238 	unsigned long val;
239 	int err;
240 
241 	err = kstrtoul(buf, 10, &val);
242 	if (err)
243 		return err;
244 
245 	mutex_lock(&data->update_lock);
246 	data->in_max[nr] = IN_TO_REG(val, nr);
247 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MAX(nr),
248 							data->in_max[nr]);
249 	mutex_unlock(&data->update_lock);
250 	return count;
251 }
252 
253 #define show_in_offset(offset)					\
254 static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
255 		show_in, NULL, offset);				\
256 static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
257 		show_in_min, set_in_min, offset);		\
258 static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
259 		show_in_max, set_in_max, offset);
260 
261 show_in_offset(0)
262 show_in_offset(1)
263 show_in_offset(2)
264 show_in_offset(3)
265 show_in_offset(4)
266 show_in_offset(5)
267 show_in_offset(6)
268 show_in_offset(7)
269 
270 /* Temperatures */
271 static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
272 		char *buf)
273 {
274 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
275 	int nr = sensor_attr->index;
276 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
277 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
278 }
279 
280 static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
281 		char *buf)
282 {
283 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
284 	int nr = sensor_attr->index;
285 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
286 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_min[nr]));
287 }
288 
289 static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr,
290 		char *buf)
291 {
292 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
293 	int nr = sensor_attr->index;
294 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
295 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max[nr]));
296 }
297 
298 static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
299 		const char *buf, size_t count)
300 {
301 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
302 	int nr = sensor_attr->index;
303 	struct smsc47m192_data *data = dev_get_drvdata(dev);
304 	struct i2c_client *client = data->client;
305 	long val;
306 	int err;
307 
308 	err = kstrtol(buf, 10, &val);
309 	if (err)
310 		return err;
311 
312 	mutex_lock(&data->update_lock);
313 	data->temp_min[nr] = TEMP_TO_REG(val);
314 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MIN[nr],
315 						data->temp_min[nr]);
316 	mutex_unlock(&data->update_lock);
317 	return count;
318 }
319 
320 static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
321 		const char *buf, size_t count)
322 {
323 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
324 	int nr = sensor_attr->index;
325 	struct smsc47m192_data *data = dev_get_drvdata(dev);
326 	struct i2c_client *client = data->client;
327 	long val;
328 	int err;
329 
330 	err = kstrtol(buf, 10, &val);
331 	if (err)
332 		return err;
333 
334 	mutex_lock(&data->update_lock);
335 	data->temp_max[nr] = TEMP_TO_REG(val);
336 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MAX[nr],
337 						data->temp_max[nr]);
338 	mutex_unlock(&data->update_lock);
339 	return count;
340 }
341 
342 static ssize_t show_temp_offset(struct device *dev, struct device_attribute
343 		*attr, char *buf)
344 {
345 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
346 	int nr = sensor_attr->index;
347 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
348 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_offset[nr]));
349 }
350 
351 static ssize_t set_temp_offset(struct device *dev, struct device_attribute
352 		*attr, const char *buf, size_t count)
353 {
354 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
355 	int nr = sensor_attr->index;
356 	struct smsc47m192_data *data = dev_get_drvdata(dev);
357 	struct i2c_client *client = data->client;
358 	u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
359 	long val;
360 	int err;
361 
362 	err = kstrtol(buf, 10, &val);
363 	if (err)
364 		return err;
365 
366 	mutex_lock(&data->update_lock);
367 	data->temp_offset[nr] = TEMP_TO_REG(val);
368 	if (nr > 1)
369 		i2c_smbus_write_byte_data(client,
370 			SMSC47M192_REG_TEMP_OFFSET(nr), data->temp_offset[nr]);
371 	else if (data->temp_offset[nr] != 0) {
372 		/*
373 		 * offset[0] and offset[1] share the same register,
374 		 * SFR bit 4 activates offset[0]
375 		 */
376 		i2c_smbus_write_byte_data(client, SMSC47M192_REG_SFR,
377 					(sfr & 0xef) | (nr == 0 ? 0x10 : 0));
378 		data->temp_offset[1-nr] = 0;
379 		i2c_smbus_write_byte_data(client,
380 			SMSC47M192_REG_TEMP_OFFSET(nr), data->temp_offset[nr]);
381 	} else if ((sfr & 0x10) == (nr == 0 ? 0x10 : 0))
382 		i2c_smbus_write_byte_data(client,
383 					SMSC47M192_REG_TEMP_OFFSET(nr), 0);
384 	mutex_unlock(&data->update_lock);
385 	return count;
386 }
387 
388 #define show_temp_index(index)						\
389 static SENSOR_DEVICE_ATTR(temp##index##_input, S_IRUGO,			\
390 		show_temp, NULL, index-1);				\
391 static SENSOR_DEVICE_ATTR(temp##index##_min, S_IRUGO | S_IWUSR,		\
392 		show_temp_min, set_temp_min, index-1);			\
393 static SENSOR_DEVICE_ATTR(temp##index##_max, S_IRUGO | S_IWUSR,		\
394 		show_temp_max, set_temp_max, index-1);			\
395 static SENSOR_DEVICE_ATTR(temp##index##_offset, S_IRUGO | S_IWUSR,	\
396 		show_temp_offset, set_temp_offset, index-1);
397 
398 show_temp_index(1)
399 show_temp_index(2)
400 show_temp_index(3)
401 
402 /* VID */
403 static ssize_t cpu0_vid_show(struct device *dev,
404 			     struct device_attribute *attr, char *buf)
405 {
406 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
407 	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
408 }
409 static DEVICE_ATTR_RO(cpu0_vid);
410 
411 static ssize_t vrm_show(struct device *dev, struct device_attribute *attr,
412 		char *buf)
413 {
414 	struct smsc47m192_data *data = dev_get_drvdata(dev);
415 	return sprintf(buf, "%d\n", data->vrm);
416 }
417 
418 static ssize_t vrm_store(struct device *dev, struct device_attribute *attr,
419 			 const char *buf, size_t count)
420 {
421 	struct smsc47m192_data *data = dev_get_drvdata(dev);
422 	unsigned long val;
423 	int err;
424 
425 	err = kstrtoul(buf, 10, &val);
426 	if (err)
427 		return err;
428 	if (val > 255)
429 		return -EINVAL;
430 
431 	data->vrm = val;
432 	return count;
433 }
434 static DEVICE_ATTR_RW(vrm);
435 
436 /* Alarms */
437 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
438 		char *buf)
439 {
440 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
441 	int nr = sensor_attr->index;
442 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
443 	return sprintf(buf, "%u\n", (data->alarms & nr) ? 1 : 0);
444 }
445 
446 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 0x0010);
447 static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 0x0020);
448 static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 0x0040);
449 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 0x4000);
450 static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 0x8000);
451 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0x0001);
452 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 0x0002);
453 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 0x0004);
454 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 0x0008);
455 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 0x0100);
456 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 0x0200);
457 static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, show_alarm, NULL, 0x0400);
458 static SENSOR_DEVICE_ATTR(in7_alarm, S_IRUGO, show_alarm, NULL, 0x0800);
459 
460 static struct attribute *smsc47m192_attributes[] = {
461 	&sensor_dev_attr_in0_input.dev_attr.attr,
462 	&sensor_dev_attr_in0_min.dev_attr.attr,
463 	&sensor_dev_attr_in0_max.dev_attr.attr,
464 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
465 	&sensor_dev_attr_in1_input.dev_attr.attr,
466 	&sensor_dev_attr_in1_min.dev_attr.attr,
467 	&sensor_dev_attr_in1_max.dev_attr.attr,
468 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
469 	&sensor_dev_attr_in2_input.dev_attr.attr,
470 	&sensor_dev_attr_in2_min.dev_attr.attr,
471 	&sensor_dev_attr_in2_max.dev_attr.attr,
472 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
473 	&sensor_dev_attr_in3_input.dev_attr.attr,
474 	&sensor_dev_attr_in3_min.dev_attr.attr,
475 	&sensor_dev_attr_in3_max.dev_attr.attr,
476 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
477 	&sensor_dev_attr_in5_input.dev_attr.attr,
478 	&sensor_dev_attr_in5_min.dev_attr.attr,
479 	&sensor_dev_attr_in5_max.dev_attr.attr,
480 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
481 	&sensor_dev_attr_in6_input.dev_attr.attr,
482 	&sensor_dev_attr_in6_min.dev_attr.attr,
483 	&sensor_dev_attr_in6_max.dev_attr.attr,
484 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
485 	&sensor_dev_attr_in7_input.dev_attr.attr,
486 	&sensor_dev_attr_in7_min.dev_attr.attr,
487 	&sensor_dev_attr_in7_max.dev_attr.attr,
488 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
489 
490 	&sensor_dev_attr_temp1_input.dev_attr.attr,
491 	&sensor_dev_attr_temp1_max.dev_attr.attr,
492 	&sensor_dev_attr_temp1_min.dev_attr.attr,
493 	&sensor_dev_attr_temp1_offset.dev_attr.attr,
494 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
495 	&sensor_dev_attr_temp2_input.dev_attr.attr,
496 	&sensor_dev_attr_temp2_max.dev_attr.attr,
497 	&sensor_dev_attr_temp2_min.dev_attr.attr,
498 	&sensor_dev_attr_temp2_offset.dev_attr.attr,
499 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
500 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
501 	&sensor_dev_attr_temp3_input.dev_attr.attr,
502 	&sensor_dev_attr_temp3_max.dev_attr.attr,
503 	&sensor_dev_attr_temp3_min.dev_attr.attr,
504 	&sensor_dev_attr_temp3_offset.dev_attr.attr,
505 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
506 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
507 
508 	&dev_attr_cpu0_vid.attr,
509 	&dev_attr_vrm.attr,
510 	NULL
511 };
512 
513 static const struct attribute_group smsc47m192_group = {
514 	.attrs = smsc47m192_attributes,
515 };
516 
517 static struct attribute *smsc47m192_attributes_in4[] = {
518 	&sensor_dev_attr_in4_input.dev_attr.attr,
519 	&sensor_dev_attr_in4_min.dev_attr.attr,
520 	&sensor_dev_attr_in4_max.dev_attr.attr,
521 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
522 	NULL
523 };
524 
525 static const struct attribute_group smsc47m192_group_in4 = {
526 	.attrs = smsc47m192_attributes_in4,
527 };
528 
529 static void smsc47m192_init_client(struct i2c_client *client)
530 {
531 	int i;
532 	u8 config = i2c_smbus_read_byte_data(client, SMSC47M192_REG_CONFIG);
533 	u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
534 
535 	/* select cycle mode (pause 1 sec between updates) */
536 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_SFR,
537 						(sfr & 0xfd) | 0x02);
538 	if (!(config & 0x01)) {
539 		/* initialize alarm limits */
540 		for (i = 0; i < 8; i++) {
541 			i2c_smbus_write_byte_data(client,
542 				SMSC47M192_REG_IN_MIN(i), 0);
543 			i2c_smbus_write_byte_data(client,
544 				SMSC47M192_REG_IN_MAX(i), 0xff);
545 		}
546 		for (i = 0; i < 3; i++) {
547 			i2c_smbus_write_byte_data(client,
548 				SMSC47M192_REG_TEMP_MIN[i], 0x80);
549 			i2c_smbus_write_byte_data(client,
550 				SMSC47M192_REG_TEMP_MAX[i], 0x7f);
551 		}
552 
553 		/* start monitoring */
554 		i2c_smbus_write_byte_data(client, SMSC47M192_REG_CONFIG,
555 						(config & 0xf7) | 0x01);
556 	}
557 }
558 
559 /* Return 0 if detection is successful, -ENODEV otherwise */
560 static int smsc47m192_detect(struct i2c_client *client,
561 			     struct i2c_board_info *info)
562 {
563 	struct i2c_adapter *adapter = client->adapter;
564 	int version;
565 
566 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
567 		return -ENODEV;
568 
569 	/* Detection criteria from sensors_detect script */
570 	version = i2c_smbus_read_byte_data(client, SMSC47M192_REG_VERSION);
571 	if (i2c_smbus_read_byte_data(client,
572 				SMSC47M192_REG_COMPANY_ID) == 0x55
573 	 && (version & 0xf0) == 0x20
574 	 && (i2c_smbus_read_byte_data(client,
575 				SMSC47M192_REG_VID) & 0x70) == 0x00
576 	 && (i2c_smbus_read_byte_data(client,
577 				SMSC47M192_REG_VID4) & 0xfe) == 0x80) {
578 		dev_info(&adapter->dev,
579 			 "found SMSC47M192 or compatible, "
580 			 "version 2, stepping A%d\n", version & 0x0f);
581 	} else {
582 		dev_dbg(&adapter->dev,
583 			"SMSC47M192 detection failed at 0x%02x\n",
584 			client->addr);
585 		return -ENODEV;
586 	}
587 
588 	strlcpy(info->type, "smsc47m192", I2C_NAME_SIZE);
589 
590 	return 0;
591 }
592 
593 static int smsc47m192_probe(struct i2c_client *client,
594 			    const struct i2c_device_id *id)
595 {
596 	struct device *dev = &client->dev;
597 	struct device *hwmon_dev;
598 	struct smsc47m192_data *data;
599 	int config;
600 
601 	data = devm_kzalloc(dev, sizeof(struct smsc47m192_data), GFP_KERNEL);
602 	if (!data)
603 		return -ENOMEM;
604 
605 	data->client = client;
606 	data->vrm = vid_which_vrm();
607 	mutex_init(&data->update_lock);
608 
609 	/* Initialize the SMSC47M192 chip */
610 	smsc47m192_init_client(client);
611 
612 	/* sysfs hooks */
613 	data->groups[0] = &smsc47m192_group;
614 	/* Pin 110 is either in4 (+12V) or VID4 */
615 	config = i2c_smbus_read_byte_data(client, SMSC47M192_REG_CONFIG);
616 	if (!(config & 0x20))
617 		data->groups[1] = &smsc47m192_group_in4;
618 
619 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
620 							   data, data->groups);
621 	return PTR_ERR_OR_ZERO(hwmon_dev);
622 }
623 
624 static const struct i2c_device_id smsc47m192_id[] = {
625 	{ "smsc47m192", 0 },
626 	{ }
627 };
628 MODULE_DEVICE_TABLE(i2c, smsc47m192_id);
629 
630 static struct i2c_driver smsc47m192_driver = {
631 	.class		= I2C_CLASS_HWMON,
632 	.driver = {
633 		.name	= "smsc47m192",
634 	},
635 	.probe		= smsc47m192_probe,
636 	.id_table	= smsc47m192_id,
637 	.detect		= smsc47m192_detect,
638 	.address_list	= normal_i2c,
639 };
640 
641 module_i2c_driver(smsc47m192_driver);
642 
643 MODULE_AUTHOR("Hartmut Rick <linux@rick.claranet.de>");
644 MODULE_DESCRIPTION("SMSC47M192 driver");
645 MODULE_LICENSE("GPL");
646