xref: /openbmc/linux/drivers/hwmon/smsc47m192.c (revision 827634ad)
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 	return clamp_val(SCALE(val, 192, nom_mv[n]), 0, 255);
81 }
82 
83 /*
84  * TEMP: 0.001 degC units (-128C to +127C)
85  * REG: 1C/bit, two's complement
86  */
87 static inline s8 TEMP_TO_REG(int val)
88 {
89 	return SCALE(clamp_val(val, -128000, 127000), 1, 1000);
90 }
91 
92 static inline int TEMP_FROM_REG(s8 val)
93 {
94 	return val * 1000;
95 }
96 
97 struct smsc47m192_data {
98 	struct i2c_client *client;
99 	const struct attribute_group *groups[3];
100 	struct mutex update_lock;
101 	char valid;		/* !=0 if following fields are valid */
102 	unsigned long last_updated;	/* In jiffies */
103 
104 	u8 in[8];		/* Register value */
105 	u8 in_max[8];		/* Register value */
106 	u8 in_min[8];		/* Register value */
107 	s8 temp[3];		/* Register value */
108 	s8 temp_max[3];		/* Register value */
109 	s8 temp_min[3];		/* Register value */
110 	s8 temp_offset[3];	/* Register value */
111 	u16 alarms;		/* Register encoding, combined */
112 	u8 vid;			/* Register encoding, combined */
113 	u8 vrm;
114 };
115 
116 static struct smsc47m192_data *smsc47m192_update_device(struct device *dev)
117 {
118 	struct smsc47m192_data *data = dev_get_drvdata(dev);
119 	struct i2c_client *client = data->client;
120 	int i, config;
121 
122 	mutex_lock(&data->update_lock);
123 
124 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
125 	 || !data->valid) {
126 		u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
127 
128 		dev_dbg(&client->dev, "Starting smsc47m192 update\n");
129 
130 		for (i = 0; i <= 7; i++) {
131 			data->in[i] = i2c_smbus_read_byte_data(client,
132 						SMSC47M192_REG_IN(i));
133 			data->in_min[i] = i2c_smbus_read_byte_data(client,
134 						SMSC47M192_REG_IN_MIN(i));
135 			data->in_max[i] = i2c_smbus_read_byte_data(client,
136 						SMSC47M192_REG_IN_MAX(i));
137 		}
138 		for (i = 0; i < 3; i++) {
139 			data->temp[i] = i2c_smbus_read_byte_data(client,
140 						SMSC47M192_REG_TEMP[i]);
141 			data->temp_max[i] = i2c_smbus_read_byte_data(client,
142 						SMSC47M192_REG_TEMP_MAX[i]);
143 			data->temp_min[i] = i2c_smbus_read_byte_data(client,
144 						SMSC47M192_REG_TEMP_MIN[i]);
145 		}
146 		for (i = 1; i < 3; i++)
147 			data->temp_offset[i] = i2c_smbus_read_byte_data(client,
148 						SMSC47M192_REG_TEMP_OFFSET(i));
149 		/*
150 		 * first offset is temp_offset[0] if SFR bit 4 is set,
151 		 * temp_offset[1] otherwise
152 		 */
153 		if (sfr & 0x10) {
154 			data->temp_offset[0] = data->temp_offset[1];
155 			data->temp_offset[1] = 0;
156 		} else
157 			data->temp_offset[0] = 0;
158 
159 		data->vid = i2c_smbus_read_byte_data(client, SMSC47M192_REG_VID)
160 			    & 0x0f;
161 		config = i2c_smbus_read_byte_data(client,
162 						  SMSC47M192_REG_CONFIG);
163 		if (config & 0x20)
164 			data->vid |= (i2c_smbus_read_byte_data(client,
165 					SMSC47M192_REG_VID4) & 0x01) << 4;
166 		data->alarms = i2c_smbus_read_byte_data(client,
167 						SMSC47M192_REG_ALARM1) |
168 			       (i2c_smbus_read_byte_data(client,
169 						SMSC47M192_REG_ALARM2) << 8);
170 
171 		data->last_updated = jiffies;
172 		data->valid = 1;
173 	}
174 
175 	mutex_unlock(&data->update_lock);
176 
177 	return data;
178 }
179 
180 /* Voltages */
181 static ssize_t show_in(struct device *dev, struct device_attribute *attr,
182 		char *buf)
183 {
184 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
185 	int nr = sensor_attr->index;
186 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
187 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[nr], nr));
188 }
189 
190 static ssize_t show_in_min(struct device *dev, struct device_attribute *attr,
191 		char *buf)
192 {
193 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
194 	int nr = sensor_attr->index;
195 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
196 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[nr], nr));
197 }
198 
199 static ssize_t show_in_max(struct device *dev, struct device_attribute *attr,
200 		char *buf)
201 {
202 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
203 	int nr = sensor_attr->index;
204 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
205 	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[nr], nr));
206 }
207 
208 static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
209 		const char *buf, size_t count)
210 {
211 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
212 	int nr = sensor_attr->index;
213 	struct smsc47m192_data *data = dev_get_drvdata(dev);
214 	struct i2c_client *client = data->client;
215 	unsigned long val;
216 	int err;
217 
218 	err = kstrtoul(buf, 10, &val);
219 	if (err)
220 		return err;
221 
222 	mutex_lock(&data->update_lock);
223 	data->in_min[nr] = IN_TO_REG(val, nr);
224 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MIN(nr),
225 							data->in_min[nr]);
226 	mutex_unlock(&data->update_lock);
227 	return count;
228 }
229 
230 static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
231 		const char *buf, size_t count)
232 {
233 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
234 	int nr = sensor_attr->index;
235 	struct smsc47m192_data *data = dev_get_drvdata(dev);
236 	struct i2c_client *client = data->client;
237 	unsigned long val;
238 	int err;
239 
240 	err = kstrtoul(buf, 10, &val);
241 	if (err)
242 		return err;
243 
244 	mutex_lock(&data->update_lock);
245 	data->in_max[nr] = IN_TO_REG(val, nr);
246 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_IN_MAX(nr),
247 							data->in_max[nr]);
248 	mutex_unlock(&data->update_lock);
249 	return count;
250 }
251 
252 #define show_in_offset(offset)					\
253 static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
254 		show_in, NULL, offset);				\
255 static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
256 		show_in_min, set_in_min, offset);		\
257 static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
258 		show_in_max, set_in_max, offset);
259 
260 show_in_offset(0)
261 show_in_offset(1)
262 show_in_offset(2)
263 show_in_offset(3)
264 show_in_offset(4)
265 show_in_offset(5)
266 show_in_offset(6)
267 show_in_offset(7)
268 
269 /* Temperatures */
270 static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
271 		char *buf)
272 {
273 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
274 	int nr = sensor_attr->index;
275 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
276 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
277 }
278 
279 static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
280 		char *buf)
281 {
282 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
283 	int nr = sensor_attr->index;
284 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
285 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_min[nr]));
286 }
287 
288 static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr,
289 		char *buf)
290 {
291 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
292 	int nr = sensor_attr->index;
293 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
294 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max[nr]));
295 }
296 
297 static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
298 		const char *buf, size_t count)
299 {
300 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
301 	int nr = sensor_attr->index;
302 	struct smsc47m192_data *data = dev_get_drvdata(dev);
303 	struct i2c_client *client = data->client;
304 	long val;
305 	int err;
306 
307 	err = kstrtol(buf, 10, &val);
308 	if (err)
309 		return err;
310 
311 	mutex_lock(&data->update_lock);
312 	data->temp_min[nr] = TEMP_TO_REG(val);
313 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MIN[nr],
314 						data->temp_min[nr]);
315 	mutex_unlock(&data->update_lock);
316 	return count;
317 }
318 
319 static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
320 		const char *buf, size_t count)
321 {
322 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
323 	int nr = sensor_attr->index;
324 	struct smsc47m192_data *data = dev_get_drvdata(dev);
325 	struct i2c_client *client = data->client;
326 	long val;
327 	int err;
328 
329 	err = kstrtol(buf, 10, &val);
330 	if (err)
331 		return err;
332 
333 	mutex_lock(&data->update_lock);
334 	data->temp_max[nr] = TEMP_TO_REG(val);
335 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_TEMP_MAX[nr],
336 						data->temp_max[nr]);
337 	mutex_unlock(&data->update_lock);
338 	return count;
339 }
340 
341 static ssize_t show_temp_offset(struct device *dev, struct device_attribute
342 		*attr, char *buf)
343 {
344 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
345 	int nr = sensor_attr->index;
346 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
347 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_offset[nr]));
348 }
349 
350 static ssize_t set_temp_offset(struct device *dev, struct device_attribute
351 		*attr, const char *buf, size_t count)
352 {
353 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
354 	int nr = sensor_attr->index;
355 	struct smsc47m192_data *data = dev_get_drvdata(dev);
356 	struct i2c_client *client = data->client;
357 	u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
358 	long val;
359 	int err;
360 
361 	err = kstrtol(buf, 10, &val);
362 	if (err)
363 		return err;
364 
365 	mutex_lock(&data->update_lock);
366 	data->temp_offset[nr] = TEMP_TO_REG(val);
367 	if (nr > 1)
368 		i2c_smbus_write_byte_data(client,
369 			SMSC47M192_REG_TEMP_OFFSET(nr), data->temp_offset[nr]);
370 	else if (data->temp_offset[nr] != 0) {
371 		/*
372 		 * offset[0] and offset[1] share the same register,
373 		 * SFR bit 4 activates offset[0]
374 		 */
375 		i2c_smbus_write_byte_data(client, SMSC47M192_REG_SFR,
376 					(sfr & 0xef) | (nr == 0 ? 0x10 : 0));
377 		data->temp_offset[1-nr] = 0;
378 		i2c_smbus_write_byte_data(client,
379 			SMSC47M192_REG_TEMP_OFFSET(nr), data->temp_offset[nr]);
380 	} else if ((sfr & 0x10) == (nr == 0 ? 0x10 : 0))
381 		i2c_smbus_write_byte_data(client,
382 					SMSC47M192_REG_TEMP_OFFSET(nr), 0);
383 	mutex_unlock(&data->update_lock);
384 	return count;
385 }
386 
387 #define show_temp_index(index)						\
388 static SENSOR_DEVICE_ATTR(temp##index##_input, S_IRUGO,			\
389 		show_temp, NULL, index-1);				\
390 static SENSOR_DEVICE_ATTR(temp##index##_min, S_IRUGO | S_IWUSR,		\
391 		show_temp_min, set_temp_min, index-1);			\
392 static SENSOR_DEVICE_ATTR(temp##index##_max, S_IRUGO | S_IWUSR,		\
393 		show_temp_max, set_temp_max, index-1);			\
394 static SENSOR_DEVICE_ATTR(temp##index##_offset, S_IRUGO | S_IWUSR,	\
395 		show_temp_offset, set_temp_offset, index-1);
396 
397 show_temp_index(1)
398 show_temp_index(2)
399 show_temp_index(3)
400 
401 /* VID */
402 static ssize_t show_vid(struct device *dev, struct device_attribute *attr,
403 		char *buf)
404 {
405 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
406 	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
407 }
408 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
409 
410 static ssize_t show_vrm(struct device *dev, struct device_attribute *attr,
411 		char *buf)
412 {
413 	struct smsc47m192_data *data = dev_get_drvdata(dev);
414 	return sprintf(buf, "%d\n", data->vrm);
415 }
416 
417 static ssize_t set_vrm(struct device *dev, struct device_attribute *attr,
418 		const char *buf, size_t count)
419 {
420 	struct smsc47m192_data *data = dev_get_drvdata(dev);
421 	unsigned long val;
422 	int err;
423 
424 	err = kstrtoul(buf, 10, &val);
425 	if (err)
426 		return err;
427 	if (val > 255)
428 		return -EINVAL;
429 
430 	data->vrm = val;
431 	return count;
432 }
433 static DEVICE_ATTR(vrm, S_IRUGO | S_IWUSR, show_vrm, set_vrm);
434 
435 /* Alarms */
436 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
437 		char *buf)
438 {
439 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
440 	int nr = sensor_attr->index;
441 	struct smsc47m192_data *data = smsc47m192_update_device(dev);
442 	return sprintf(buf, "%u\n", (data->alarms & nr) ? 1 : 0);
443 }
444 
445 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 0x0010);
446 static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 0x0020);
447 static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 0x0040);
448 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 0x4000);
449 static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 0x8000);
450 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0x0001);
451 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 0x0002);
452 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 0x0004);
453 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 0x0008);
454 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 0x0100);
455 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 0x0200);
456 static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, show_alarm, NULL, 0x0400);
457 static SENSOR_DEVICE_ATTR(in7_alarm, S_IRUGO, show_alarm, NULL, 0x0800);
458 
459 static struct attribute *smsc47m192_attributes[] = {
460 	&sensor_dev_attr_in0_input.dev_attr.attr,
461 	&sensor_dev_attr_in0_min.dev_attr.attr,
462 	&sensor_dev_attr_in0_max.dev_attr.attr,
463 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
464 	&sensor_dev_attr_in1_input.dev_attr.attr,
465 	&sensor_dev_attr_in1_min.dev_attr.attr,
466 	&sensor_dev_attr_in1_max.dev_attr.attr,
467 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
468 	&sensor_dev_attr_in2_input.dev_attr.attr,
469 	&sensor_dev_attr_in2_min.dev_attr.attr,
470 	&sensor_dev_attr_in2_max.dev_attr.attr,
471 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
472 	&sensor_dev_attr_in3_input.dev_attr.attr,
473 	&sensor_dev_attr_in3_min.dev_attr.attr,
474 	&sensor_dev_attr_in3_max.dev_attr.attr,
475 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
476 	&sensor_dev_attr_in5_input.dev_attr.attr,
477 	&sensor_dev_attr_in5_min.dev_attr.attr,
478 	&sensor_dev_attr_in5_max.dev_attr.attr,
479 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
480 	&sensor_dev_attr_in6_input.dev_attr.attr,
481 	&sensor_dev_attr_in6_min.dev_attr.attr,
482 	&sensor_dev_attr_in6_max.dev_attr.attr,
483 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
484 	&sensor_dev_attr_in7_input.dev_attr.attr,
485 	&sensor_dev_attr_in7_min.dev_attr.attr,
486 	&sensor_dev_attr_in7_max.dev_attr.attr,
487 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
488 
489 	&sensor_dev_attr_temp1_input.dev_attr.attr,
490 	&sensor_dev_attr_temp1_max.dev_attr.attr,
491 	&sensor_dev_attr_temp1_min.dev_attr.attr,
492 	&sensor_dev_attr_temp1_offset.dev_attr.attr,
493 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
494 	&sensor_dev_attr_temp2_input.dev_attr.attr,
495 	&sensor_dev_attr_temp2_max.dev_attr.attr,
496 	&sensor_dev_attr_temp2_min.dev_attr.attr,
497 	&sensor_dev_attr_temp2_offset.dev_attr.attr,
498 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
499 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
500 	&sensor_dev_attr_temp3_input.dev_attr.attr,
501 	&sensor_dev_attr_temp3_max.dev_attr.attr,
502 	&sensor_dev_attr_temp3_min.dev_attr.attr,
503 	&sensor_dev_attr_temp3_offset.dev_attr.attr,
504 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
505 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
506 
507 	&dev_attr_cpu0_vid.attr,
508 	&dev_attr_vrm.attr,
509 	NULL
510 };
511 
512 static const struct attribute_group smsc47m192_group = {
513 	.attrs = smsc47m192_attributes,
514 };
515 
516 static struct attribute *smsc47m192_attributes_in4[] = {
517 	&sensor_dev_attr_in4_input.dev_attr.attr,
518 	&sensor_dev_attr_in4_min.dev_attr.attr,
519 	&sensor_dev_attr_in4_max.dev_attr.attr,
520 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
521 	NULL
522 };
523 
524 static const struct attribute_group smsc47m192_group_in4 = {
525 	.attrs = smsc47m192_attributes_in4,
526 };
527 
528 static void smsc47m192_init_client(struct i2c_client *client)
529 {
530 	int i;
531 	u8 config = i2c_smbus_read_byte_data(client, SMSC47M192_REG_CONFIG);
532 	u8 sfr = i2c_smbus_read_byte_data(client, SMSC47M192_REG_SFR);
533 
534 	/* select cycle mode (pause 1 sec between updates) */
535 	i2c_smbus_write_byte_data(client, SMSC47M192_REG_SFR,
536 						(sfr & 0xfd) | 0x02);
537 	if (!(config & 0x01)) {
538 		/* initialize alarm limits */
539 		for (i = 0; i < 8; i++) {
540 			i2c_smbus_write_byte_data(client,
541 				SMSC47M192_REG_IN_MIN(i), 0);
542 			i2c_smbus_write_byte_data(client,
543 				SMSC47M192_REG_IN_MAX(i), 0xff);
544 		}
545 		for (i = 0; i < 3; i++) {
546 			i2c_smbus_write_byte_data(client,
547 				SMSC47M192_REG_TEMP_MIN[i], 0x80);
548 			i2c_smbus_write_byte_data(client,
549 				SMSC47M192_REG_TEMP_MAX[i], 0x7f);
550 		}
551 
552 		/* start monitoring */
553 		i2c_smbus_write_byte_data(client, SMSC47M192_REG_CONFIG,
554 						(config & 0xf7) | 0x01);
555 	}
556 }
557 
558 /* Return 0 if detection is successful, -ENODEV otherwise */
559 static int smsc47m192_detect(struct i2c_client *client,
560 			     struct i2c_board_info *info)
561 {
562 	struct i2c_adapter *adapter = client->adapter;
563 	int version;
564 
565 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
566 		return -ENODEV;
567 
568 	/* Detection criteria from sensors_detect script */
569 	version = i2c_smbus_read_byte_data(client, SMSC47M192_REG_VERSION);
570 	if (i2c_smbus_read_byte_data(client,
571 				SMSC47M192_REG_COMPANY_ID) == 0x55
572 	 && (version & 0xf0) == 0x20
573 	 && (i2c_smbus_read_byte_data(client,
574 				SMSC47M192_REG_VID) & 0x70) == 0x00
575 	 && (i2c_smbus_read_byte_data(client,
576 				SMSC47M192_REG_VID4) & 0xfe) == 0x80) {
577 		dev_info(&adapter->dev,
578 			 "found SMSC47M192 or compatible, "
579 			 "version 2, stepping A%d\n", version & 0x0f);
580 	} else {
581 		dev_dbg(&adapter->dev,
582 			"SMSC47M192 detection failed at 0x%02x\n",
583 			client->addr);
584 		return -ENODEV;
585 	}
586 
587 	strlcpy(info->type, "smsc47m192", I2C_NAME_SIZE);
588 
589 	return 0;
590 }
591 
592 static int smsc47m192_probe(struct i2c_client *client,
593 			    const struct i2c_device_id *id)
594 {
595 	struct device *dev = &client->dev;
596 	struct device *hwmon_dev;
597 	struct smsc47m192_data *data;
598 	int config;
599 
600 	data = devm_kzalloc(dev, sizeof(struct smsc47m192_data), GFP_KERNEL);
601 	if (!data)
602 		return -ENOMEM;
603 
604 	data->client = client;
605 	data->vrm = vid_which_vrm();
606 	mutex_init(&data->update_lock);
607 
608 	/* Initialize the SMSC47M192 chip */
609 	smsc47m192_init_client(client);
610 
611 	/* sysfs hooks */
612 	data->groups[0] = &smsc47m192_group;
613 	/* Pin 110 is either in4 (+12V) or VID4 */
614 	config = i2c_smbus_read_byte_data(client, SMSC47M192_REG_CONFIG);
615 	if (!(config & 0x20))
616 		data->groups[1] = &smsc47m192_group_in4;
617 
618 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
619 							   data, data->groups);
620 	return PTR_ERR_OR_ZERO(hwmon_dev);
621 }
622 
623 static const struct i2c_device_id smsc47m192_id[] = {
624 	{ "smsc47m192", 0 },
625 	{ }
626 };
627 MODULE_DEVICE_TABLE(i2c, smsc47m192_id);
628 
629 static struct i2c_driver smsc47m192_driver = {
630 	.class		= I2C_CLASS_HWMON,
631 	.driver = {
632 		.name	= "smsc47m192",
633 	},
634 	.probe		= smsc47m192_probe,
635 	.id_table	= smsc47m192_id,
636 	.detect		= smsc47m192_detect,
637 	.address_list	= normal_i2c,
638 };
639 
640 module_i2c_driver(smsc47m192_driver);
641 
642 MODULE_AUTHOR("Hartmut Rick <linux@rick.claranet.de>");
643 MODULE_DESCRIPTION("SMSC47M192 driver");
644 MODULE_LICENSE("GPL");
645