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 */
37static 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)))
46static u8 SMSC47M192_REG_TEMP[3] =	{ 0x27, 0x26, 0x52 };
47static u8 SMSC47M192_REG_TEMP_MAX[3] =	{ 0x39, 0x37, 0x58 };
48static 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 */
60static 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 */
71static const u16 nom_mv[] = { 2500, 2250, 3300, 5000, 12000, 3300, 1500, 1800 };
72
73static inline unsigned int IN_FROM_REG(u8 reg, int n)
74{
75	return SCALE(reg, nom_mv[n], 192);
76}
77
78static 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 */
87static inline s8 TEMP_TO_REG(int val)
88{
89	return SCALE(clamp_val(val, -128000, 127000), 1, 1000);
90}
91
92static inline int TEMP_FROM_REG(s8 val)
93{
94	return val * 1000;
95}
96
97struct 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
116static 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 */
181static 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
190static 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
199static 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
208static 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
230static 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)					\
253static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
254		show_in, NULL, offset);				\
255static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
256		show_in_min, set_in_min, offset);		\
257static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
258		show_in_max, set_in_max, offset);
259
260show_in_offset(0)
261show_in_offset(1)
262show_in_offset(2)
263show_in_offset(3)
264show_in_offset(4)
265show_in_offset(5)
266show_in_offset(6)
267show_in_offset(7)
268
269/* Temperatures */
270static 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
279static 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
288static 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
297static 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
319static 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
341static 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
350static 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)						\
388static SENSOR_DEVICE_ATTR(temp##index##_input, S_IRUGO,			\
389		show_temp, NULL, index-1);				\
390static SENSOR_DEVICE_ATTR(temp##index##_min, S_IRUGO | S_IWUSR,		\
391		show_temp_min, set_temp_min, index-1);			\
392static SENSOR_DEVICE_ATTR(temp##index##_max, S_IRUGO | S_IWUSR,		\
393		show_temp_max, set_temp_max, index-1);			\
394static SENSOR_DEVICE_ATTR(temp##index##_offset, S_IRUGO | S_IWUSR,	\
395		show_temp_offset, set_temp_offset, index-1);
396
397show_temp_index(1)
398show_temp_index(2)
399show_temp_index(3)
400
401/* VID */
402static 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}
408static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
409
410static 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
417static 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}
433static DEVICE_ATTR(vrm, S_IRUGO | S_IWUSR, show_vrm, set_vrm);
434
435/* Alarms */
436static 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
445static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 0x0010);
446static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 0x0020);
447static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 0x0040);
448static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 0x4000);
449static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 0x8000);
450static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0x0001);
451static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 0x0002);
452static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 0x0004);
453static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 0x0008);
454static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 0x0100);
455static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 0x0200);
456static SENSOR_DEVICE_ATTR(in6_alarm, S_IRUGO, show_alarm, NULL, 0x0400);
457static SENSOR_DEVICE_ATTR(in7_alarm, S_IRUGO, show_alarm, NULL, 0x0800);
458
459static 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
512static const struct attribute_group smsc47m192_group = {
513	.attrs = smsc47m192_attributes,
514};
515
516static 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
524static const struct attribute_group smsc47m192_group_in4 = {
525	.attrs = smsc47m192_attributes_in4,
526};
527
528static 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 */
559static 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
592static 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
623static const struct i2c_device_id smsc47m192_id[] = {
624	{ "smsc47m192", 0 },
625	{ }
626};
627MODULE_DEVICE_TABLE(i2c, smsc47m192_id);
628
629static 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
640module_i2c_driver(smsc47m192_driver);
641
642MODULE_AUTHOR("Hartmut Rick <linux@rick.claranet.de>");
643MODULE_DESCRIPTION("SMSC47M192 driver");
644MODULE_LICENSE("GPL");
645