2 * lm95241.c - Part of lm_sensors, Linux kernel modules for hardware
4 * Copyright (C) 2008 Davide Rizzo <elpa-rizzo@gmail.com>
6 * Based on the max1619 driver. The LM95241 is a sensor chip made by National
8 * It reports up to three temperatures (its own plus up to
9 * two external ones). Complete datasheet can be
10 * obtained from National's website at:
11 * http://www.national.com/ds.cgi/LM/LM95241.pdf
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.
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.
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.
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/jiffies.h>
32 #include <linux/i2c.h>
33 #include <linux/hwmon.h>
34 #include <linux/hwmon-sysfs.h>
35 #include <linux/err.h>
36 #include <linux/mutex.h>
37 #include <linux/sysfs.h>
39 static const unsigned short normal_i2c[] = {
40 0x19, 0x2a, 0x2b, I2C_CLIENT_END};
42 /* Insmod parameters */
43 I2C_CLIENT_INSMOD_1(lm95241);
45 /* LM95241 registers */
46 #define LM95241_REG_R_MAN_ID 0xFE
47 #define LM95241_REG_R_CHIP_ID 0xFF
48 #define LM95241_REG_R_STATUS 0x02
49 #define LM95241_REG_RW_CONFIG 0x03
50 #define LM95241_REG_RW_REM_FILTER 0x06
51 #define LM95241_REG_RW_TRUTHERM 0x07
52 #define LM95241_REG_W_ONE_SHOT 0x0F
53 #define LM95241_REG_R_LOCAL_TEMPH 0x10
54 #define LM95241_REG_R_REMOTE1_TEMPH 0x11
55 #define LM95241_REG_R_REMOTE2_TEMPH 0x12
56 #define LM95241_REG_R_LOCAL_TEMPL 0x20
57 #define LM95241_REG_R_REMOTE1_TEMPL 0x21
58 #define LM95241_REG_R_REMOTE2_TEMPL 0x22
59 #define LM95241_REG_RW_REMOTE_MODEL 0x30
61 /* LM95241 specific bitfields */
63 #define CFG_CR0076 0x00
64 #define CFG_CR0182 0x10
65 #define CFG_CR1000 0x20
66 #define CFG_CR2700 0x30
69 #define R1MS_MASK (0x01 << (R1MS_SHIFT))
70 #define R2MS_MASK (0x01 << (R2MS_SHIFT))
73 #define R1DF_MASK (0x01 << (R1DF_SHIFT))
74 #define R2DF_MASK (0x01 << (R2DF_SHIFT))
75 #define R1FE_MASK 0x01
76 #define R2FE_MASK 0x05
82 #define MANUFACTURER_ID 0x01
83 #define DEFAULT_REVISION 0xA4
85 /* Conversions and various macros */
86 #define TEMP_FROM_REG(val_h, val_l) (((val_h) & 0x80 ? (val_h) - 0x100 : \
87 (val_h)) * 1000 + (val_l) * 1000 / 256)
89 /* Functions declaration */
90 static void lm95241_init_client(struct i2c_client *client);
91 static struct lm95241_data *lm95241_update_device(struct device *dev);
93 /* Client data (each client gets its own) */
95 struct device *hwmon_dev;
96 struct mutex update_lock;
97 unsigned long last_updated, rate; /* in jiffies */
98 char valid; /* zero until following fields are valid */
99 /* registers values */
100 u8 local_h, local_l; /* local */
101 u8 remote1_h, remote1_l; /* remote1 */
102 u8 remote2_h, remote2_l; /* remote2 */
103 u8 config, model, trutherm;
107 #define show_temp(value) \
108 static ssize_t show_##value(struct device *dev, \
109 struct device_attribute *attr, char *buf) \
111 struct lm95241_data *data = lm95241_update_device(dev); \
112 snprintf(buf, PAGE_SIZE - 1, "%d\n", \
113 TEMP_FROM_REG(data->value##_h, data->value##_l)); \
114 return strlen(buf); \
120 static ssize_t show_rate(struct device *dev, struct device_attribute *attr,
123 struct lm95241_data *data = lm95241_update_device(dev);
125 snprintf(buf, PAGE_SIZE - 1, "%lu\n", 1000 * data->rate / HZ);
129 static ssize_t set_rate(struct device *dev, struct device_attribute *attr,
130 const char *buf, size_t count)
132 struct i2c_client *client = to_i2c_client(dev);
133 struct lm95241_data *data = i2c_get_clientdata(client);
135 strict_strtol(buf, 10, &data->rate);
136 data->rate = data->rate * HZ / 1000;
141 #define show_type(flag) \
142 static ssize_t show_type##flag(struct device *dev, \
143 struct device_attribute *attr, char *buf) \
145 struct i2c_client *client = to_i2c_client(dev); \
146 struct lm95241_data *data = i2c_get_clientdata(client); \
148 snprintf(buf, PAGE_SIZE - 1, \
149 data->model & R##flag##MS_MASK ? "1\n" : "2\n"); \
150 return strlen(buf); \
155 #define show_min(flag) \
156 static ssize_t show_min##flag(struct device *dev, \
157 struct device_attribute *attr, char *buf) \
159 struct i2c_client *client = to_i2c_client(dev); \
160 struct lm95241_data *data = i2c_get_clientdata(client); \
162 snprintf(buf, PAGE_SIZE - 1, \
163 data->config & R##flag##DF_MASK ? \
164 "-127000\n" : "0\n"); \
165 return strlen(buf); \
170 #define show_max(flag) \
171 static ssize_t show_max##flag(struct device *dev, \
172 struct device_attribute *attr, char *buf) \
174 struct i2c_client *client = to_i2c_client(dev); \
175 struct lm95241_data *data = i2c_get_clientdata(client); \
177 snprintf(buf, PAGE_SIZE - 1, \
178 data->config & R##flag##DF_MASK ? \
179 "127000\n" : "255000\n"); \
180 return strlen(buf); \
185 #define set_type(flag) \
186 static ssize_t set_type##flag(struct device *dev, \
187 struct device_attribute *attr, \
188 const char *buf, size_t count) \
190 struct i2c_client *client = to_i2c_client(dev); \
191 struct lm95241_data *data = i2c_get_clientdata(client); \
194 strict_strtol(buf, 10, &val); \
196 if ((val == 1) || (val == 2)) { \
198 mutex_lock(&data->update_lock); \
200 data->trutherm &= ~(TT_MASK << TT##flag##_SHIFT); \
202 data->model |= R##flag##MS_MASK; \
203 data->trutherm |= (TT_ON << TT##flag##_SHIFT); \
206 data->model &= ~R##flag##MS_MASK; \
207 data->trutherm |= (TT_OFF << TT##flag##_SHIFT); \
212 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL, \
214 i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM, \
217 mutex_unlock(&data->update_lock); \
225 #define set_min(flag) \
226 static ssize_t set_min##flag(struct device *dev, \
227 struct device_attribute *devattr, const char *buf, size_t count) \
229 struct i2c_client *client = to_i2c_client(dev); \
230 struct lm95241_data *data = i2c_get_clientdata(client); \
233 strict_strtol(buf, 10, &val); \
235 mutex_lock(&data->update_lock); \
238 data->config |= R##flag##DF_MASK; \
240 data->config &= ~R##flag##DF_MASK; \
244 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \
247 mutex_unlock(&data->update_lock); \
254 #define set_max(flag) \
255 static ssize_t set_max##flag(struct device *dev, \
256 struct device_attribute *devattr, const char *buf, size_t count) \
258 struct i2c_client *client = to_i2c_client(dev); \
259 struct lm95241_data *data = i2c_get_clientdata(client); \
262 strict_strtol(buf, 10, &val); \
264 mutex_lock(&data->update_lock); \
267 data->config |= R##flag##DF_MASK; \
269 data->config &= ~R##flag##DF_MASK; \
273 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG, \
276 mutex_unlock(&data->update_lock); \
283 static DEVICE_ATTR(temp1_input, S_IRUGO, show_local, NULL);
284 static DEVICE_ATTR(temp2_input, S_IRUGO, show_remote1, NULL);
285 static DEVICE_ATTR(temp3_input, S_IRUGO, show_remote2, NULL);
286 static DEVICE_ATTR(temp2_type, S_IWUSR | S_IRUGO, show_type1, set_type1);
287 static DEVICE_ATTR(temp3_type, S_IWUSR | S_IRUGO, show_type2, set_type2);
288 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_min1, set_min1);
289 static DEVICE_ATTR(temp3_min, S_IWUSR | S_IRUGO, show_min2, set_min2);
290 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_max1, set_max1);
291 static DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_max2, set_max2);
292 static DEVICE_ATTR(rate, S_IWUSR | S_IRUGO, show_rate, set_rate);
294 static struct attribute *lm95241_attributes[] = {
295 &dev_attr_temp1_input.attr,
296 &dev_attr_temp2_input.attr,
297 &dev_attr_temp3_input.attr,
298 &dev_attr_temp2_type.attr,
299 &dev_attr_temp3_type.attr,
300 &dev_attr_temp2_min.attr,
301 &dev_attr_temp3_min.attr,
302 &dev_attr_temp2_max.attr,
303 &dev_attr_temp3_max.attr,
308 static const struct attribute_group lm95241_group = {
309 .attrs = lm95241_attributes,
312 /* Return 0 if detection is successful, -ENODEV otherwise */
313 static int lm95241_detect(struct i2c_client *new_client, int kind,
314 struct i2c_board_info *info)
316 struct i2c_adapter *adapter = new_client->adapter;
317 int address = new_client->addr;
320 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
323 if ((i2c_smbus_read_byte_data(new_client, LM95241_REG_R_MAN_ID)
325 && (i2c_smbus_read_byte_data(new_client, LM95241_REG_R_CHIP_ID)
326 >= DEFAULT_REVISION)) {
329 dev_dbg(&adapter->dev, "LM95241 detection failed at 0x%02x\n",
334 /* Fill the i2c board info */
335 strlcpy(info->type, name, I2C_NAME_SIZE);
339 static int lm95241_probe(struct i2c_client *new_client,
340 const struct i2c_device_id *id)
342 struct lm95241_data *data;
345 data = kzalloc(sizeof(struct lm95241_data), GFP_KERNEL);
351 i2c_set_clientdata(new_client, data);
352 mutex_init(&data->update_lock);
354 /* Initialize the LM95241 chip */
355 lm95241_init_client(new_client);
357 /* Register sysfs hooks */
358 err = sysfs_create_group(&new_client->dev.kobj, &lm95241_group);
362 data->hwmon_dev = hwmon_device_register(&new_client->dev);
363 if (IS_ERR(data->hwmon_dev)) {
364 err = PTR_ERR(data->hwmon_dev);
365 goto exit_remove_files;
371 sysfs_remove_group(&new_client->dev.kobj, &lm95241_group);
378 static void lm95241_init_client(struct i2c_client *client)
380 struct lm95241_data *data = i2c_get_clientdata(client);
382 data->rate = HZ; /* 1 sec default */
384 data->config = CFG_CR0076;
386 data->trutherm = (TT_OFF << TT1_SHIFT) | (TT_OFF << TT2_SHIFT);
388 i2c_smbus_write_byte_data(client, LM95241_REG_RW_CONFIG,
390 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REM_FILTER,
391 R1FE_MASK | R2FE_MASK);
392 i2c_smbus_write_byte_data(client, LM95241_REG_RW_TRUTHERM,
394 i2c_smbus_write_byte_data(client, LM95241_REG_RW_REMOTE_MODEL,
398 static int lm95241_remove(struct i2c_client *client)
400 struct lm95241_data *data = i2c_get_clientdata(client);
402 hwmon_device_unregister(data->hwmon_dev);
403 sysfs_remove_group(&client->dev.kobj, &lm95241_group);
405 i2c_set_clientdata(client, NULL);
410 static struct lm95241_data *lm95241_update_device(struct device *dev)
412 struct i2c_client *client = to_i2c_client(dev);
413 struct lm95241_data *data = i2c_get_clientdata(client);
415 mutex_lock(&data->update_lock);
417 if (time_after(jiffies, data->last_updated + data->rate) ||
419 dev_dbg(&client->dev, "Updating lm95241 data.\n");
421 i2c_smbus_read_byte_data(client,
422 LM95241_REG_R_LOCAL_TEMPH);
424 i2c_smbus_read_byte_data(client,
425 LM95241_REG_R_LOCAL_TEMPL);
427 i2c_smbus_read_byte_data(client,
428 LM95241_REG_R_REMOTE1_TEMPH);
430 i2c_smbus_read_byte_data(client,
431 LM95241_REG_R_REMOTE1_TEMPL);
433 i2c_smbus_read_byte_data(client,
434 LM95241_REG_R_REMOTE2_TEMPH);
436 i2c_smbus_read_byte_data(client,
437 LM95241_REG_R_REMOTE2_TEMPL);
438 data->last_updated = jiffies;
442 mutex_unlock(&data->update_lock);
447 /* Driver data (common to all clients) */
448 static const struct i2c_device_id lm95241_id[] = {
449 { "lm95241", lm95241 },
452 MODULE_DEVICE_TABLE(i2c, lm95241_id);
454 static struct i2c_driver lm95241_driver = {
455 .class = I2C_CLASS_HWMON,
459 .probe = lm95241_probe,
460 .remove = lm95241_remove,
461 .id_table = lm95241_id,
462 .detect = lm95241_detect,
463 .address_data = &addr_data,
466 static int __init sensors_lm95241_init(void)
468 return i2c_add_driver(&lm95241_driver);
471 static void __exit sensors_lm95241_exit(void)
473 i2c_del_driver(&lm95241_driver);
476 MODULE_AUTHOR("Davide Rizzo <elpa-rizzo@gmail.com>");
477 MODULE_DESCRIPTION("LM95241 sensor driver");
478 MODULE_LICENSE("GPL");
480 module_init(sensors_lm95241_init);
481 module_exit(sensors_lm95241_exit);