xref: /openbmc/linux/drivers/hwmon/adm1025.c (revision a1e58bbd)
1 /*
2  * adm1025.c
3  *
4  * Copyright (C) 2000       Chen-Yuan Wu <gwu@esoft.com>
5  * Copyright (C) 2003-2004  Jean Delvare <khali@linux-fr.org>
6  *
7  * The ADM1025 is a sensor chip made by Analog Devices. It reports up to 6
8  * voltages (including its own power source) and up to two temperatures
9  * (its own plus up to one external one). Voltages are scaled internally
10  * (which is not the common way) with ratios such that the nominal value
11  * of each voltage correspond to a register value of 192 (which means a
12  * resolution of about 0.5% of the nominal value). Temperature values are
13  * reported with a 1 deg resolution and a 3 deg accuracy. Complete
14  * datasheet can be obtained from Analog's website at:
15  *   http://www.analog.com/Analog_Root/productPage/productHome/0,2121,ADM1025,00.html
16  *
17  * This driver also supports the ADM1025A, which differs from the ADM1025
18  * only in that it has "open-drain VID inputs while the ADM1025 has
19  * on-chip 100k pull-ups on the VID inputs". It doesn't make any
20  * difference for us.
21  *
22  * This driver also supports the NE1619, a sensor chip made by Philips.
23  * That chip is similar to the ADM1025A, with a few differences. The only
24  * difference that matters to us is that the NE1619 has only two possible
25  * addresses while the ADM1025A has a third one. Complete datasheet can be
26  * obtained from Philips's website at:
27  *   http://www.semiconductors.philips.com/pip/NE1619DS.html
28  *
29  * Since the ADM1025 was the first chipset supported by this driver, most
30  * comments will refer to this chipset, but are actually general and
31  * concern all supported chipsets, unless mentioned otherwise.
32  *
33  * This program is free software; you can redistribute it and/or modify
34  * it under the terms of the GNU General Public License as published by
35  * the Free Software Foundation; either version 2 of the License, or
36  * (at your option) any later version.
37  *
38  * This program is distributed in the hope that it will be useful,
39  * but WITHOUT ANY WARRANTY; without even the implied warranty of
40  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
41  * GNU General Public License for more details.
42  *
43  * You should have received a copy of the GNU General Public License
44  * along with this program; if not, write to the Free Software
45  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
46  */
47 
48 #include <linux/module.h>
49 #include <linux/init.h>
50 #include <linux/slab.h>
51 #include <linux/jiffies.h>
52 #include <linux/i2c.h>
53 #include <linux/hwmon.h>
54 #include <linux/hwmon-sysfs.h>
55 #include <linux/hwmon-vid.h>
56 #include <linux/err.h>
57 #include <linux/mutex.h>
58 
59 /*
60  * Addresses to scan
61  * ADM1025 and ADM1025A have three possible addresses: 0x2c, 0x2d and 0x2e.
62  * NE1619 has two possible addresses: 0x2c and 0x2d.
63  */
64 
65 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };
66 
67 /*
68  * Insmod parameters
69  */
70 
71 I2C_CLIENT_INSMOD_2(adm1025, ne1619);
72 
73 /*
74  * The ADM1025 registers
75  */
76 
77 #define ADM1025_REG_MAN_ID		0x3E
78 #define ADM1025_REG_CHIP_ID		0x3F
79 #define ADM1025_REG_CONFIG		0x40
80 #define ADM1025_REG_STATUS1		0x41
81 #define ADM1025_REG_STATUS2		0x42
82 #define ADM1025_REG_IN(nr)		(0x20 + (nr))
83 #define ADM1025_REG_IN_MAX(nr)		(0x2B + (nr) * 2)
84 #define ADM1025_REG_IN_MIN(nr)		(0x2C + (nr) * 2)
85 #define ADM1025_REG_TEMP(nr)		(0x26 + (nr))
86 #define ADM1025_REG_TEMP_HIGH(nr)	(0x37 + (nr) * 2)
87 #define ADM1025_REG_TEMP_LOW(nr)	(0x38 + (nr) * 2)
88 #define ADM1025_REG_VID			0x47
89 #define ADM1025_REG_VID4		0x49
90 
91 /*
92  * Conversions and various macros
93  * The ADM1025 uses signed 8-bit values for temperatures.
94  */
95 
96 static const int in_scale[6] = { 2500, 2250, 3300, 5000, 12000, 3300 };
97 
98 #define IN_FROM_REG(reg,scale)	(((reg) * (scale) + 96) / 192)
99 #define IN_TO_REG(val,scale)	((val) <= 0 ? 0 : \
100 				 (val) * 192 >= (scale) * 255 ? 255 : \
101 				 ((val) * 192 + (scale)/2) / (scale))
102 
103 #define TEMP_FROM_REG(reg)	((reg) * 1000)
104 #define TEMP_TO_REG(val)	((val) <= -127500 ? -128 : \
105 				 (val) >= 126500 ? 127 : \
106 				 (((val) < 0 ? (val)-500 : (val)+500) / 1000))
107 
108 /*
109  * Functions declaration
110  */
111 
112 static int adm1025_attach_adapter(struct i2c_adapter *adapter);
113 static int adm1025_detect(struct i2c_adapter *adapter, int address, int kind);
114 static void adm1025_init_client(struct i2c_client *client);
115 static int adm1025_detach_client(struct i2c_client *client);
116 static struct adm1025_data *adm1025_update_device(struct device *dev);
117 
118 /*
119  * Driver data (common to all clients)
120  */
121 
122 static struct i2c_driver adm1025_driver = {
123 	.driver = {
124 		.name	= "adm1025",
125 	},
126 	.attach_adapter	= adm1025_attach_adapter,
127 	.detach_client	= adm1025_detach_client,
128 };
129 
130 /*
131  * Client data (each client gets its own)
132  */
133 
134 struct adm1025_data {
135 	struct i2c_client client;
136 	struct device *hwmon_dev;
137 	struct mutex update_lock;
138 	char valid; /* zero until following fields are valid */
139 	unsigned long last_updated; /* in jiffies */
140 
141 	u8 in[6];		/* register value */
142 	u8 in_max[6];		/* register value */
143 	u8 in_min[6];		/* register value */
144 	s8 temp[2];		/* register value */
145 	s8 temp_min[2];		/* register value */
146 	s8 temp_max[2];		/* register value */
147 	u16 alarms;		/* register values, combined */
148 	u8 vid;			/* register values, combined */
149 	u8 vrm;
150 };
151 
152 /*
153  * Sysfs stuff
154  */
155 
156 static ssize_t
157 show_in(struct device *dev, struct device_attribute *attr, char *buf)
158 {
159 	int index = to_sensor_dev_attr(attr)->index;
160 	struct adm1025_data *data = adm1025_update_device(dev);
161 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in[index],
162 		       in_scale[index]));
163 }
164 
165 static ssize_t
166 show_in_min(struct device *dev, struct device_attribute *attr, char *buf)
167 {
168 	int index = to_sensor_dev_attr(attr)->index;
169 	struct adm1025_data *data = adm1025_update_device(dev);
170 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_min[index],
171 		       in_scale[index]));
172 }
173 
174 static ssize_t
175 show_in_max(struct device *dev, struct device_attribute *attr, char *buf)
176 {
177 	int index = to_sensor_dev_attr(attr)->index;
178 	struct adm1025_data *data = adm1025_update_device(dev);
179 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_max[index],
180 		       in_scale[index]));
181 }
182 
183 static ssize_t
184 show_temp(struct device *dev, struct device_attribute *attr, char *buf)
185 {
186 	int index = to_sensor_dev_attr(attr)->index;
187 	struct adm1025_data *data = adm1025_update_device(dev);
188 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[index]));
189 }
190 
191 static ssize_t
192 show_temp_min(struct device *dev, struct device_attribute *attr, char *buf)
193 {
194 	int index = to_sensor_dev_attr(attr)->index;
195 	struct adm1025_data *data = adm1025_update_device(dev);
196 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_min[index]));
197 }
198 
199 static ssize_t
200 show_temp_max(struct device *dev, struct device_attribute *attr, char *buf)
201 {
202 	int index = to_sensor_dev_attr(attr)->index;
203 	struct adm1025_data *data = adm1025_update_device(dev);
204 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_max[index]));
205 }
206 
207 static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
208 			  const char *buf, size_t count)
209 {
210 	int index = to_sensor_dev_attr(attr)->index;
211 	struct i2c_client *client = to_i2c_client(dev);
212 	struct adm1025_data *data = i2c_get_clientdata(client);
213 	long val = simple_strtol(buf, NULL, 10);
214 
215 	mutex_lock(&data->update_lock);
216 	data->in_min[index] = IN_TO_REG(val, in_scale[index]);
217 	i2c_smbus_write_byte_data(client, ADM1025_REG_IN_MIN(index),
218 				  data->in_min[index]);
219 	mutex_unlock(&data->update_lock);
220 	return count;
221 }
222 
223 static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
224 			  const char *buf, size_t count)
225 {
226 	int index = to_sensor_dev_attr(attr)->index;
227 	struct i2c_client *client = to_i2c_client(dev);
228 	struct adm1025_data *data = i2c_get_clientdata(client);
229 	long val = simple_strtol(buf, NULL, 10);
230 
231 	mutex_lock(&data->update_lock);
232 	data->in_max[index] = IN_TO_REG(val, in_scale[index]);
233 	i2c_smbus_write_byte_data(client, ADM1025_REG_IN_MAX(index),
234 				  data->in_max[index]);
235 	mutex_unlock(&data->update_lock);
236 	return count;
237 }
238 
239 #define set_in(offset) \
240 static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, \
241 	show_in, NULL, offset); \
242 static SENSOR_DEVICE_ATTR(in##offset##_min, S_IWUSR | S_IRUGO, \
243 	show_in_min, set_in_min, offset); \
244 static SENSOR_DEVICE_ATTR(in##offset##_max, S_IWUSR | S_IRUGO, \
245 	show_in_max, set_in_max, offset)
246 set_in(0);
247 set_in(1);
248 set_in(2);
249 set_in(3);
250 set_in(4);
251 set_in(5);
252 
253 static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
254 			    const char *buf, size_t count)
255 {
256 	int index = to_sensor_dev_attr(attr)->index;
257 	struct i2c_client *client = to_i2c_client(dev);
258 	struct adm1025_data *data = i2c_get_clientdata(client);
259 	long val = simple_strtol(buf, NULL, 10);
260 
261 	mutex_lock(&data->update_lock);
262 	data->temp_min[index] = TEMP_TO_REG(val);
263 	i2c_smbus_write_byte_data(client, ADM1025_REG_TEMP_LOW(index),
264 				  data->temp_min[index]);
265 	mutex_unlock(&data->update_lock);
266 	return count;
267 }
268 
269 static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
270 	const char *buf, size_t count)
271 {
272 	int index = to_sensor_dev_attr(attr)->index;
273 	struct i2c_client *client = to_i2c_client(dev);
274 	struct adm1025_data *data = i2c_get_clientdata(client);
275 	long val = simple_strtol(buf, NULL, 10);
276 
277 	mutex_lock(&data->update_lock);
278 	data->temp_max[index] = TEMP_TO_REG(val);
279 	i2c_smbus_write_byte_data(client, ADM1025_REG_TEMP_HIGH(index),
280 				  data->temp_max[index]);
281 	mutex_unlock(&data->update_lock);
282 	return count;
283 }
284 
285 #define set_temp(offset) \
286 static SENSOR_DEVICE_ATTR(temp##offset##_input, S_IRUGO, \
287 	show_temp, NULL, offset - 1); \
288 static SENSOR_DEVICE_ATTR(temp##offset##_min, S_IWUSR | S_IRUGO, \
289 	show_temp_min, set_temp_min, offset - 1); \
290 static SENSOR_DEVICE_ATTR(temp##offset##_max, S_IWUSR | S_IRUGO, \
291 	show_temp_max, set_temp_max, offset - 1)
292 set_temp(1);
293 set_temp(2);
294 
295 static ssize_t
296 show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
297 {
298 	struct adm1025_data *data = adm1025_update_device(dev);
299 	return sprintf(buf, "%u\n", data->alarms);
300 }
301 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
302 
303 static ssize_t
304 show_alarm(struct device *dev, struct device_attribute *attr, char *buf)
305 {
306 	int bitnr = to_sensor_dev_attr(attr)->index;
307 	struct adm1025_data *data = adm1025_update_device(dev);
308 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
309 }
310 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0);
311 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 1);
312 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 2);
313 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
314 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 8);
315 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 9);
316 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 5);
317 static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 4);
318 static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, show_alarm, NULL, 14);
319 
320 static ssize_t
321 show_vid(struct device *dev, struct device_attribute *attr, char *buf)
322 {
323 	struct adm1025_data *data = adm1025_update_device(dev);
324 	return sprintf(buf, "%u\n", vid_from_reg(data->vid, data->vrm));
325 }
326 static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
327 
328 static ssize_t
329 show_vrm(struct device *dev, struct device_attribute *attr, char *buf)
330 {
331 	struct adm1025_data *data = dev_get_drvdata(dev);
332 	return sprintf(buf, "%u\n", data->vrm);
333 }
334 static ssize_t set_vrm(struct device *dev, struct device_attribute *attr,
335 		       const char *buf, size_t count)
336 {
337 	struct adm1025_data *data = dev_get_drvdata(dev);
338 	data->vrm = simple_strtoul(buf, NULL, 10);
339 	return count;
340 }
341 static DEVICE_ATTR(vrm, S_IRUGO | S_IWUSR, show_vrm, set_vrm);
342 
343 /*
344  * Real code
345  */
346 
347 static int adm1025_attach_adapter(struct i2c_adapter *adapter)
348 {
349 	if (!(adapter->class & I2C_CLASS_HWMON))
350 		return 0;
351 	return i2c_probe(adapter, &addr_data, adm1025_detect);
352 }
353 
354 static struct attribute *adm1025_attributes[] = {
355 	&sensor_dev_attr_in0_input.dev_attr.attr,
356 	&sensor_dev_attr_in1_input.dev_attr.attr,
357 	&sensor_dev_attr_in2_input.dev_attr.attr,
358 	&sensor_dev_attr_in3_input.dev_attr.attr,
359 	&sensor_dev_attr_in5_input.dev_attr.attr,
360 	&sensor_dev_attr_in0_min.dev_attr.attr,
361 	&sensor_dev_attr_in1_min.dev_attr.attr,
362 	&sensor_dev_attr_in2_min.dev_attr.attr,
363 	&sensor_dev_attr_in3_min.dev_attr.attr,
364 	&sensor_dev_attr_in5_min.dev_attr.attr,
365 	&sensor_dev_attr_in0_max.dev_attr.attr,
366 	&sensor_dev_attr_in1_max.dev_attr.attr,
367 	&sensor_dev_attr_in2_max.dev_attr.attr,
368 	&sensor_dev_attr_in3_max.dev_attr.attr,
369 	&sensor_dev_attr_in5_max.dev_attr.attr,
370 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
371 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
372 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
373 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
374 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
375 	&sensor_dev_attr_temp1_input.dev_attr.attr,
376 	&sensor_dev_attr_temp2_input.dev_attr.attr,
377 	&sensor_dev_attr_temp1_min.dev_attr.attr,
378 	&sensor_dev_attr_temp2_min.dev_attr.attr,
379 	&sensor_dev_attr_temp1_max.dev_attr.attr,
380 	&sensor_dev_attr_temp2_max.dev_attr.attr,
381 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
382 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
383 	&sensor_dev_attr_temp1_fault.dev_attr.attr,
384 	&dev_attr_alarms.attr,
385 	&dev_attr_cpu0_vid.attr,
386 	&dev_attr_vrm.attr,
387 	NULL
388 };
389 
390 static const struct attribute_group adm1025_group = {
391 	.attrs = adm1025_attributes,
392 };
393 
394 static struct attribute *adm1025_attributes_in4[] = {
395 	&sensor_dev_attr_in4_input.dev_attr.attr,
396 	&sensor_dev_attr_in4_min.dev_attr.attr,
397 	&sensor_dev_attr_in4_max.dev_attr.attr,
398 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
399 	NULL
400 };
401 
402 static const struct attribute_group adm1025_group_in4 = {
403 	.attrs = adm1025_attributes_in4,
404 };
405 
406 /*
407  * The following function does more than just detection. If detection
408  * succeeds, it also registers the new chip.
409  */
410 static int adm1025_detect(struct i2c_adapter *adapter, int address, int kind)
411 {
412 	struct i2c_client *client;
413 	struct adm1025_data *data;
414 	int err = 0;
415 	const char *name = "";
416 	u8 config;
417 
418 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
419 		goto exit;
420 
421 	if (!(data = kzalloc(sizeof(struct adm1025_data), GFP_KERNEL))) {
422 		err = -ENOMEM;
423 		goto exit;
424 	}
425 
426 	client = &data->client;
427 	i2c_set_clientdata(client, data);
428 	client->addr = address;
429 	client->adapter = adapter;
430 	client->driver = &adm1025_driver;
431 
432 	/*
433 	 * Now we do the remaining detection. A negative kind means that
434 	 * the driver was loaded with no force parameter (default), so we
435 	 * must both detect and identify the chip. A zero kind means that
436 	 * the driver was loaded with the force parameter, the detection
437 	 * step shall be skipped. A positive kind means that the driver
438 	 * was loaded with the force parameter and a given kind of chip is
439 	 * requested, so both the detection and the identification steps
440 	 * are skipped.
441 	 */
442 	config = i2c_smbus_read_byte_data(client, ADM1025_REG_CONFIG);
443 	if (kind < 0) { /* detection */
444 		if ((config & 0x80) != 0x00
445 		 || (i2c_smbus_read_byte_data(client,
446 		     ADM1025_REG_STATUS1) & 0xC0) != 0x00
447 		 || (i2c_smbus_read_byte_data(client,
448 		     ADM1025_REG_STATUS2) & 0xBC) != 0x00) {
449 			dev_dbg(&adapter->dev,
450 				"ADM1025 detection failed at 0x%02x.\n",
451 				address);
452 			goto exit_free;
453 		}
454 	}
455 
456 	if (kind <= 0) { /* identification */
457 		u8 man_id, chip_id;
458 
459 		man_id = i2c_smbus_read_byte_data(client, ADM1025_REG_MAN_ID);
460 		chip_id = i2c_smbus_read_byte_data(client, ADM1025_REG_CHIP_ID);
461 
462 		if (man_id == 0x41) { /* Analog Devices */
463 			if ((chip_id & 0xF0) == 0x20) { /* ADM1025/ADM1025A */
464 				kind = adm1025;
465 			}
466 		} else
467 		if (man_id == 0xA1) { /* Philips */
468 			if (address != 0x2E
469 			 && (chip_id & 0xF0) == 0x20) { /* NE1619 */
470 				kind = ne1619;
471 			}
472 		}
473 
474 		if (kind <= 0) { /* identification failed */
475 			dev_info(&adapter->dev,
476 			    "Unsupported chip (man_id=0x%02X, "
477 			    "chip_id=0x%02X).\n", man_id, chip_id);
478 			goto exit_free;
479 		}
480 	}
481 
482 	if (kind == adm1025) {
483 		name = "adm1025";
484 	} else if (kind == ne1619) {
485 		name = "ne1619";
486 	}
487 
488 	/* We can fill in the remaining client fields */
489 	strlcpy(client->name, name, I2C_NAME_SIZE);
490 	mutex_init(&data->update_lock);
491 
492 	/* Tell the I2C layer a new client has arrived */
493 	if ((err = i2c_attach_client(client)))
494 		goto exit_free;
495 
496 	/* Initialize the ADM1025 chip */
497 	adm1025_init_client(client);
498 
499 	/* Register sysfs hooks */
500 	if ((err = sysfs_create_group(&client->dev.kobj, &adm1025_group)))
501 		goto exit_detach;
502 
503 	/* Pin 11 is either in4 (+12V) or VID4 */
504 	if (!(config & 0x20)) {
505 		if ((err = sysfs_create_group(&client->dev.kobj,
506 					      &adm1025_group_in4)))
507 			goto exit_remove;
508 	}
509 
510 	data->hwmon_dev = hwmon_device_register(&client->dev);
511 	if (IS_ERR(data->hwmon_dev)) {
512 		err = PTR_ERR(data->hwmon_dev);
513 		goto exit_remove;
514 	}
515 
516 	return 0;
517 
518 exit_remove:
519 	sysfs_remove_group(&client->dev.kobj, &adm1025_group);
520 	sysfs_remove_group(&client->dev.kobj, &adm1025_group_in4);
521 exit_detach:
522 	i2c_detach_client(client);
523 exit_free:
524 	kfree(data);
525 exit:
526 	return err;
527 }
528 
529 static void adm1025_init_client(struct i2c_client *client)
530 {
531 	u8 reg;
532 	struct adm1025_data *data = i2c_get_clientdata(client);
533 	int i;
534 
535 	data->vrm = vid_which_vrm();
536 
537 	/*
538 	 * Set high limits
539 	 * Usually we avoid setting limits on driver init, but it happens
540 	 * that the ADM1025 comes with stupid default limits (all registers
541 	 * set to 0). In case the chip has not gone through any limit
542 	 * setting yet, we better set the high limits to the max so that
543 	 * no alarm triggers.
544 	 */
545 	for (i=0; i<6; i++) {
546 		reg = i2c_smbus_read_byte_data(client,
547 					       ADM1025_REG_IN_MAX(i));
548 		if (reg == 0)
549 			i2c_smbus_write_byte_data(client,
550 						  ADM1025_REG_IN_MAX(i),
551 						  0xFF);
552 	}
553 	for (i=0; i<2; i++) {
554 		reg = i2c_smbus_read_byte_data(client,
555 					       ADM1025_REG_TEMP_HIGH(i));
556 		if (reg == 0)
557 			i2c_smbus_write_byte_data(client,
558 						  ADM1025_REG_TEMP_HIGH(i),
559 						  0x7F);
560 	}
561 
562 	/*
563 	 * Start the conversions
564 	 */
565 	reg = i2c_smbus_read_byte_data(client, ADM1025_REG_CONFIG);
566 	if (!(reg & 0x01))
567 		i2c_smbus_write_byte_data(client, ADM1025_REG_CONFIG,
568 					  (reg&0x7E)|0x01);
569 }
570 
571 static int adm1025_detach_client(struct i2c_client *client)
572 {
573 	struct adm1025_data *data = i2c_get_clientdata(client);
574 	int err;
575 
576 	hwmon_device_unregister(data->hwmon_dev);
577 	sysfs_remove_group(&client->dev.kobj, &adm1025_group);
578 	sysfs_remove_group(&client->dev.kobj, &adm1025_group_in4);
579 
580 	if ((err = i2c_detach_client(client)))
581 		return err;
582 
583 	kfree(data);
584 	return 0;
585 }
586 
587 static struct adm1025_data *adm1025_update_device(struct device *dev)
588 {
589 	struct i2c_client *client = to_i2c_client(dev);
590 	struct adm1025_data *data = i2c_get_clientdata(client);
591 
592 	mutex_lock(&data->update_lock);
593 
594 	if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
595 		int i;
596 
597 		dev_dbg(&client->dev, "Updating data.\n");
598 		for (i=0; i<6; i++) {
599 			data->in[i] = i2c_smbus_read_byte_data(client,
600 				      ADM1025_REG_IN(i));
601 			data->in_min[i] = i2c_smbus_read_byte_data(client,
602 					  ADM1025_REG_IN_MIN(i));
603 			data->in_max[i] = i2c_smbus_read_byte_data(client,
604 					  ADM1025_REG_IN_MAX(i));
605 		}
606 		for (i=0; i<2; i++) {
607 			data->temp[i] = i2c_smbus_read_byte_data(client,
608 					ADM1025_REG_TEMP(i));
609 			data->temp_min[i] = i2c_smbus_read_byte_data(client,
610 					    ADM1025_REG_TEMP_LOW(i));
611 			data->temp_max[i] = i2c_smbus_read_byte_data(client,
612 					    ADM1025_REG_TEMP_HIGH(i));
613 		}
614 		data->alarms = i2c_smbus_read_byte_data(client,
615 			       ADM1025_REG_STATUS1)
616 			     | (i2c_smbus_read_byte_data(client,
617 				ADM1025_REG_STATUS2) << 8);
618 		data->vid = (i2c_smbus_read_byte_data(client,
619 			     ADM1025_REG_VID) & 0x0f)
620 			  | ((i2c_smbus_read_byte_data(client,
621 			      ADM1025_REG_VID4) & 0x01) << 4);
622 
623 		data->last_updated = jiffies;
624 		data->valid = 1;
625 	}
626 
627 	mutex_unlock(&data->update_lock);
628 
629 	return data;
630 }
631 
632 static int __init sensors_adm1025_init(void)
633 {
634 	return i2c_add_driver(&adm1025_driver);
635 }
636 
637 static void __exit sensors_adm1025_exit(void)
638 {
639 	i2c_del_driver(&adm1025_driver);
640 }
641 
642 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
643 MODULE_DESCRIPTION("ADM1025 driver");
644 MODULE_LICENSE("GPL");
645 
646 module_init(sensors_adm1025_init);
647 module_exit(sensors_adm1025_exit);
648