blob: b28a297be50c68267366139f2e0310bc87fdb54a [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 lm77.c - Part of lm_sensors, Linux kernel modules for hardware
3 monitoring
4
5 Copyright (c) 2004 Andras BALI <drewie@freemail.hu>
6
7 Heavily based on lm75.c by Frodo Looijaard <frodol@dds.nl>. The LM77
8 is a temperature sensor and thermal window comparator with 0.5 deg
9 resolution made by National Semiconductor. Complete datasheet can be
10 obtained at their site:
11 http://www.national.com/pf/LM/LM77.html
12
13 This program is free software; you can redistribute it and/or modify
14 it under the terms of the GNU General Public License as published by
15 the Free Software Foundation; either version 2 of the License, or
16 (at your option) any later version.
17
18 This program is distributed in the hope that it will be useful,
19 but WITHOUT ANY WARRANTY; without even the implied warranty of
20 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 GNU General Public License for more details.
22
23 You should have received a copy of the GNU General Public License
24 along with this program; if not, write to the Free Software
25 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26*/
27
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/module.h>
29#include <linux/init.h>
30#include <linux/slab.h>
31#include <linux/jiffies.h>
32#include <linux/i2c.h>
Mark M. Hoffman943b0832005-07-15 21:39:18 -040033#include <linux/hwmon.h>
Jean Delvare1f52af02008-01-03 23:35:33 +010034#include <linux/hwmon-sysfs.h>
Mark M. Hoffman943b0832005-07-15 21:39:18 -040035#include <linux/err.h>
Ingo Molnar9a61bf62006-01-18 23:19:26 +010036#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38/* Addresses to scan */
Mark M. Hoffman25e9c862008-02-17 22:28:03 -050039static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
40 I2C_CLIENT_END };
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
Linus Torvalds1da177e2005-04-16 15:20:36 -070042/* The LM77 registers */
43#define LM77_REG_TEMP 0x00
44#define LM77_REG_CONF 0x01
45#define LM77_REG_TEMP_HYST 0x02
46#define LM77_REG_TEMP_CRIT 0x03
47#define LM77_REG_TEMP_MIN 0x04
48#define LM77_REG_TEMP_MAX 0x05
49
50/* Each client has this additional data */
51struct lm77_data {
Tony Jones1beeffe2007-08-20 13:46:20 -070052 struct device *hwmon_dev;
Ingo Molnar9a61bf62006-01-18 23:19:26 +010053 struct mutex update_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 char valid;
55 unsigned long last_updated; /* In jiffies */
56 int temp_input; /* Temperatures */
57 int temp_crit;
58 int temp_min;
59 int temp_max;
60 int temp_hyst;
61 u8 alarms;
62};
63
Jean Delvarea189dd62008-07-16 19:30:13 +020064static int lm77_probe(struct i2c_client *client,
65 const struct i2c_device_id *id);
Jean Delvare310ec792009-12-14 21:17:23 +010066static int lm77_detect(struct i2c_client *client, struct i2c_board_info *info);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067static void lm77_init_client(struct i2c_client *client);
Jean Delvarea189dd62008-07-16 19:30:13 +020068static int lm77_remove(struct i2c_client *client);
Linus Torvalds1da177e2005-04-16 15:20:36 -070069static u16 lm77_read_value(struct i2c_client *client, u8 reg);
70static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value);
71
72static struct lm77_data *lm77_update_device(struct device *dev);
73
74
Jean Delvarea189dd62008-07-16 19:30:13 +020075static const struct i2c_device_id lm77_id[] = {
Jean Delvare1f86df42009-12-14 21:17:26 +010076 { "lm77", 0 },
Jean Delvarea189dd62008-07-16 19:30:13 +020077 { }
78};
79MODULE_DEVICE_TABLE(i2c, lm77_id);
80
Linus Torvalds1da177e2005-04-16 15:20:36 -070081/* This is the driver that will be inserted */
82static struct i2c_driver lm77_driver = {
Jean Delvarea189dd62008-07-16 19:30:13 +020083 .class = I2C_CLASS_HWMON,
Laurent Riffardcdaf7932005-11-26 20:37:41 +010084 .driver = {
Laurent Riffardcdaf7932005-11-26 20:37:41 +010085 .name = "lm77",
86 },
Jean Delvarea189dd62008-07-16 19:30:13 +020087 .probe = lm77_probe,
88 .remove = lm77_remove,
89 .id_table = lm77_id,
90 .detect = lm77_detect,
Jean Delvarec3813d62009-12-14 21:17:25 +010091 .address_list = normal_i2c,
Linus Torvalds1da177e2005-04-16 15:20:36 -070092};
93
94/* straight from the datasheet */
95#define LM77_TEMP_MIN (-55000)
96#define LM77_TEMP_MAX 125000
97
98/* In the temperature registers, the low 3 bits are not part of the
99 temperature values; they are the status bits. */
Jean Delvare413b6452006-01-09 22:43:08 +0100100static inline s16 LM77_TEMP_TO_REG(int temp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700101{
102 int ntemp = SENSORS_LIMIT(temp, LM77_TEMP_MIN, LM77_TEMP_MAX);
Jean Delvare413b6452006-01-09 22:43:08 +0100103 return (ntemp / 500) * 8;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104}
105
Jean Delvare413b6452006-01-09 22:43:08 +0100106static inline int LM77_TEMP_FROM_REG(s16 reg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107{
Jean Delvare413b6452006-01-09 22:43:08 +0100108 return (reg / 8) * 500;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109}
110
111/* sysfs stuff */
112
113/* read routines for temperature limits */
114#define show(value) \
Yani Ioannou8627f9b2005-05-17 06:42:03 -0400115static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116{ \
117 struct lm77_data *data = lm77_update_device(dev); \
118 return sprintf(buf, "%d\n", data->value); \
119}
120
121show(temp_input);
122show(temp_crit);
123show(temp_min);
124show(temp_max);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
126/* read routines for hysteresis values */
Yani Ioannou8627f9b2005-05-17 06:42:03 -0400127static ssize_t show_temp_crit_hyst(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128{
129 struct lm77_data *data = lm77_update_device(dev);
130 return sprintf(buf, "%d\n", data->temp_crit - data->temp_hyst);
131}
Yani Ioannou8627f9b2005-05-17 06:42:03 -0400132static ssize_t show_temp_min_hyst(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133{
134 struct lm77_data *data = lm77_update_device(dev);
135 return sprintf(buf, "%d\n", data->temp_min + data->temp_hyst);
136}
Yani Ioannou8627f9b2005-05-17 06:42:03 -0400137static ssize_t show_temp_max_hyst(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700138{
139 struct lm77_data *data = lm77_update_device(dev);
140 return sprintf(buf, "%d\n", data->temp_max - data->temp_hyst);
141}
142
143/* write routines */
144#define set(value, reg) \
Yani Ioannou8627f9b2005-05-17 06:42:03 -0400145static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146{ \
147 struct i2c_client *client = to_i2c_client(dev); \
148 struct lm77_data *data = i2c_get_clientdata(client); \
Christian Hohnstaedt5bfedac2007-08-16 11:40:10 +0200149 long val = simple_strtol(buf, NULL, 10); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 \
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100151 mutex_lock(&data->update_lock); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 data->value = val; \
153 lm77_write_value(client, reg, LM77_TEMP_TO_REG(data->value)); \
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100154 mutex_unlock(&data->update_lock); \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 return count; \
156}
157
158set(temp_min, LM77_REG_TEMP_MIN);
159set(temp_max, LM77_REG_TEMP_MAX);
160
161/* hysteresis is stored as a relative value on the chip, so it has to be
162 converted first */
Yani Ioannou8627f9b2005-05-17 06:42:03 -0400163static ssize_t set_temp_crit_hyst(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164{
165 struct i2c_client *client = to_i2c_client(dev);
166 struct lm77_data *data = i2c_get_clientdata(client);
167 unsigned long val = simple_strtoul(buf, NULL, 10);
168
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100169 mutex_lock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 data->temp_hyst = data->temp_crit - val;
171 lm77_write_value(client, LM77_REG_TEMP_HYST,
172 LM77_TEMP_TO_REG(data->temp_hyst));
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100173 mutex_unlock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 return count;
175}
176
177/* preserve hysteresis when setting T_crit */
Yani Ioannou8627f9b2005-05-17 06:42:03 -0400178static ssize_t set_temp_crit(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179{
180 struct i2c_client *client = to_i2c_client(dev);
181 struct lm77_data *data = i2c_get_clientdata(client);
182 long val = simple_strtoul(buf, NULL, 10);
183 int oldcrithyst;
184
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100185 mutex_lock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 oldcrithyst = data->temp_crit - data->temp_hyst;
187 data->temp_crit = val;
188 data->temp_hyst = data->temp_crit - oldcrithyst;
189 lm77_write_value(client, LM77_REG_TEMP_CRIT,
190 LM77_TEMP_TO_REG(data->temp_crit));
191 lm77_write_value(client, LM77_REG_TEMP_HYST,
192 LM77_TEMP_TO_REG(data->temp_hyst));
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100193 mutex_unlock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 return count;
195}
196
Jean Delvare1f52af02008-01-03 23:35:33 +0100197static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
198 char *buf)
199{
200 int bitnr = to_sensor_dev_attr(attr)->index;
201 struct lm77_data *data = lm77_update_device(dev);
202 return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
203}
204
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205static DEVICE_ATTR(temp1_input, S_IRUGO,
206 show_temp_input, NULL);
207static DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
208 show_temp_crit, set_temp_crit);
209static DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
210 show_temp_min, set_temp_min);
211static DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
212 show_temp_max, set_temp_max);
213
214static DEVICE_ATTR(temp1_crit_hyst, S_IWUSR | S_IRUGO,
215 show_temp_crit_hyst, set_temp_crit_hyst);
216static DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
217 show_temp_min_hyst, NULL);
218static DEVICE_ATTR(temp1_max_hyst, S_IRUGO,
219 show_temp_max_hyst, NULL);
220
Jean Delvare1f52af02008-01-03 23:35:33 +0100221static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 2);
222static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_alarm, NULL, 0);
223static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224
Mark M. Hoffman0501a3812006-09-24 21:14:35 +0200225static struct attribute *lm77_attributes[] = {
226 &dev_attr_temp1_input.attr,
227 &dev_attr_temp1_crit.attr,
228 &dev_attr_temp1_min.attr,
229 &dev_attr_temp1_max.attr,
230 &dev_attr_temp1_crit_hyst.attr,
231 &dev_attr_temp1_min_hyst.attr,
232 &dev_attr_temp1_max_hyst.attr,
Jean Delvare1f52af02008-01-03 23:35:33 +0100233 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
234 &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
235 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
Mark M. Hoffman0501a3812006-09-24 21:14:35 +0200236 NULL
237};
238
239static const struct attribute_group lm77_group = {
240 .attrs = lm77_attributes,
241};
242
Jean Delvarea189dd62008-07-16 19:30:13 +0200243/* Return 0 if detection is successful, -ENODEV otherwise */
Jean Delvare310ec792009-12-14 21:17:23 +0100244static int lm77_detect(struct i2c_client *new_client,
Jean Delvarea189dd62008-07-16 19:30:13 +0200245 struct i2c_board_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246{
Jean Delvarea189dd62008-07-16 19:30:13 +0200247 struct i2c_adapter *adapter = new_client->adapter;
Jean Delvare747d9be2009-12-09 20:35:52 +0100248 int i, cur, conf, hyst, crit, min, max;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249
250 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
251 I2C_FUNC_SMBUS_WORD_DATA))
Jean Delvarea189dd62008-07-16 19:30:13 +0200252 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
254 /* Here comes the remaining detection. Since the LM77 has no
255 register dedicated to identification, we have to rely on the
256 following tricks:
257
258 1. the high 4 bits represent the sign and thus they should
259 always be the same
260 2. the high 3 bits are unused in the configuration register
261 3. addresses 0x06 and 0x07 return the last read value
262 4. registers cycling over 8-address boundaries
263
264 Word-sized registers are high-byte first. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265
Jean Delvare747d9be2009-12-09 20:35:52 +0100266 /* addresses cycling */
267 cur = i2c_smbus_read_word_data(new_client, 0);
268 conf = i2c_smbus_read_byte_data(new_client, 1);
269 hyst = i2c_smbus_read_word_data(new_client, 2);
270 crit = i2c_smbus_read_word_data(new_client, 3);
271 min = i2c_smbus_read_word_data(new_client, 4);
272 max = i2c_smbus_read_word_data(new_client, 5);
273 for (i = 8; i <= 0xff; i += 8) {
274 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
275 || i2c_smbus_read_word_data(new_client, i + 2) != hyst
276 || i2c_smbus_read_word_data(new_client, i + 3) != crit
277 || i2c_smbus_read_word_data(new_client, i + 4) != min
278 || i2c_smbus_read_word_data(new_client, i + 5) != max)
Jean Delvarea189dd62008-07-16 19:30:13 +0200279 return -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 }
281
Jean Delvare747d9be2009-12-09 20:35:52 +0100282 /* sign bits */
283 if (((cur & 0x00f0) != 0xf0 && (cur & 0x00f0) != 0x0)
284 || ((hyst & 0x00f0) != 0xf0 && (hyst & 0x00f0) != 0x0)
285 || ((crit & 0x00f0) != 0xf0 && (crit & 0x00f0) != 0x0)
286 || ((min & 0x00f0) != 0xf0 && (min & 0x00f0) != 0x0)
287 || ((max & 0x00f0) != 0xf0 && (max & 0x00f0) != 0x0))
288 return -ENODEV;
289
290 /* unused bits */
291 if (conf & 0xe0)
292 return -ENODEV;
293
294 /* 0x06 and 0x07 return the last read value */
295 cur = i2c_smbus_read_word_data(new_client, 0);
296 if (i2c_smbus_read_word_data(new_client, 6) != cur
297 || i2c_smbus_read_word_data(new_client, 7) != cur)
298 return -ENODEV;
299 hyst = i2c_smbus_read_word_data(new_client, 2);
300 if (i2c_smbus_read_word_data(new_client, 6) != hyst
301 || i2c_smbus_read_word_data(new_client, 7) != hyst)
302 return -ENODEV;
303 min = i2c_smbus_read_word_data(new_client, 4);
304 if (i2c_smbus_read_word_data(new_client, 6) != min
305 || i2c_smbus_read_word_data(new_client, 7) != min)
306 return -ENODEV;
307
Jean Delvarea189dd62008-07-16 19:30:13 +0200308 strlcpy(info->type, "lm77", I2C_NAME_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309
Jean Delvarea189dd62008-07-16 19:30:13 +0200310 return 0;
311}
312
313static int lm77_probe(struct i2c_client *new_client,
314 const struct i2c_device_id *id)
315{
316 struct lm77_data *data;
317 int err;
318
319 data = kzalloc(sizeof(struct lm77_data), GFP_KERNEL);
320 if (!data) {
321 err = -ENOMEM;
322 goto exit;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 }
324
Jean Delvarea189dd62008-07-16 19:30:13 +0200325 i2c_set_clientdata(new_client, data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 data->valid = 0;
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100327 mutex_init(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 /* Initialize the LM77 chip */
330 lm77_init_client(new_client);
331
332 /* Register sysfs hooks */
Mark M. Hoffman0501a3812006-09-24 21:14:35 +0200333 if ((err = sysfs_create_group(&new_client->dev.kobj, &lm77_group)))
Jean Delvarea189dd62008-07-16 19:30:13 +0200334 goto exit_free;
Mark M. Hoffman0501a3812006-09-24 21:14:35 +0200335
Tony Jones1beeffe2007-08-20 13:46:20 -0700336 data->hwmon_dev = hwmon_device_register(&new_client->dev);
337 if (IS_ERR(data->hwmon_dev)) {
338 err = PTR_ERR(data->hwmon_dev);
Mark M. Hoffman0501a3812006-09-24 21:14:35 +0200339 goto exit_remove;
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400340 }
341
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 return 0;
343
Mark M. Hoffman0501a3812006-09-24 21:14:35 +0200344exit_remove:
345 sysfs_remove_group(&new_client->dev.kobj, &lm77_group);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346exit_free:
347 kfree(data);
348exit:
349 return err;
350}
351
Jean Delvarea189dd62008-07-16 19:30:13 +0200352static int lm77_remove(struct i2c_client *client)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353{
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400354 struct lm77_data *data = i2c_get_clientdata(client);
Tony Jones1beeffe2007-08-20 13:46:20 -0700355 hwmon_device_unregister(data->hwmon_dev);
Mark M. Hoffman0501a3812006-09-24 21:14:35 +0200356 sysfs_remove_group(&client->dev.kobj, &lm77_group);
Mark M. Hoffman943b0832005-07-15 21:39:18 -0400357 kfree(data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358 return 0;
359}
360
361/* All registers are word-sized, except for the configuration register.
362 The LM77 uses the high-byte first convention. */
363static u16 lm77_read_value(struct i2c_client *client, u8 reg)
364{
365 if (reg == LM77_REG_CONF)
366 return i2c_smbus_read_byte_data(client, reg);
367 else
368 return swab16(i2c_smbus_read_word_data(client, reg));
369}
370
371static int lm77_write_value(struct i2c_client *client, u8 reg, u16 value)
372{
373 if (reg == LM77_REG_CONF)
374 return i2c_smbus_write_byte_data(client, reg, value);
375 else
376 return i2c_smbus_write_word_data(client, reg, swab16(value));
377}
378
379static void lm77_init_client(struct i2c_client *client)
380{
381 /* Initialize the LM77 chip - turn off shutdown mode */
382 int conf = lm77_read_value(client, LM77_REG_CONF);
383 if (conf & 1)
384 lm77_write_value(client, LM77_REG_CONF, conf & 0xfe);
385}
386
387static struct lm77_data *lm77_update_device(struct device *dev)
388{
389 struct i2c_client *client = to_i2c_client(dev);
390 struct lm77_data *data = i2c_get_clientdata(client);
391
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100392 mutex_lock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393
394 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
395 || !data->valid) {
396 dev_dbg(&client->dev, "Starting lm77 update\n");
397 data->temp_input =
398 LM77_TEMP_FROM_REG(lm77_read_value(client,
399 LM77_REG_TEMP));
400 data->temp_hyst =
401 LM77_TEMP_FROM_REG(lm77_read_value(client,
402 LM77_REG_TEMP_HYST));
403 data->temp_crit =
404 LM77_TEMP_FROM_REG(lm77_read_value(client,
405 LM77_REG_TEMP_CRIT));
406 data->temp_min =
407 LM77_TEMP_FROM_REG(lm77_read_value(client,
408 LM77_REG_TEMP_MIN));
409 data->temp_max =
410 LM77_TEMP_FROM_REG(lm77_read_value(client,
411 LM77_REG_TEMP_MAX));
412 data->alarms =
413 lm77_read_value(client, LM77_REG_TEMP) & 0x0007;
414 data->last_updated = jiffies;
415 data->valid = 1;
416 }
417
Ingo Molnar9a61bf62006-01-18 23:19:26 +0100418 mutex_unlock(&data->update_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419
420 return data;
421}
422
423static int __init sensors_lm77_init(void)
424{
425 return i2c_add_driver(&lm77_driver);
426}
427
428static void __exit sensors_lm77_exit(void)
429{
430 i2c_del_driver(&lm77_driver);
431}
432
433MODULE_AUTHOR("Andras BALI <drewie@freemail.hu>");
434MODULE_DESCRIPTION("LM77 driver");
435MODULE_LICENSE("GPL");
436
437module_init(sensors_lm77_init);
438module_exit(sensors_lm77_exit);