2 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
4 * Copyright (C) 2003-2005 Jean Delvare <khali@linux-fr.org>
6 * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is
7 * a sensor chip made by National Semiconductor. It reports up to four
8 * temperatures (its own plus up to three external ones) with a 1 deg
9 * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained
10 * from National's website at:
11 * http://www.national.com/pf/LM/LM83.html
12 * Since the datasheet omits to give the chip stepping code, I give it
13 * here: 0x03 (at register 0xff).
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/slab.h>
33 #include <linux/jiffies.h>
34 #include <linux/i2c.h>
35 #include <linux/i2c-sensor.h>
36 #include <linux/hwmon-sysfs.h>
37 #include <linux/hwmon.h>
38 #include <linux/err.h>
42 * Address is selected using 2 three-level pins, resulting in 9 possible
46 static unsigned short normal_i2c[] = { 0x18, 0x19, 0x1a,
55 SENSORS_INSMOD_1(lm83);
59 * Manufacturer ID is 0x01 for National Semiconductor.
62 #define LM83_REG_R_MAN_ID 0xFE
63 #define LM83_REG_R_CHIP_ID 0xFF
64 #define LM83_REG_R_CONFIG 0x03
65 #define LM83_REG_W_CONFIG 0x09
66 #define LM83_REG_R_STATUS1 0x02
67 #define LM83_REG_R_STATUS2 0x35
68 #define LM83_REG_R_LOCAL_TEMP 0x00
69 #define LM83_REG_R_LOCAL_HIGH 0x05
70 #define LM83_REG_W_LOCAL_HIGH 0x0B
71 #define LM83_REG_R_REMOTE1_TEMP 0x30
72 #define LM83_REG_R_REMOTE1_HIGH 0x38
73 #define LM83_REG_W_REMOTE1_HIGH 0x50
74 #define LM83_REG_R_REMOTE2_TEMP 0x01
75 #define LM83_REG_R_REMOTE2_HIGH 0x07
76 #define LM83_REG_W_REMOTE2_HIGH 0x0D
77 #define LM83_REG_R_REMOTE3_TEMP 0x31
78 #define LM83_REG_R_REMOTE3_HIGH 0x3A
79 #define LM83_REG_W_REMOTE3_HIGH 0x52
80 #define LM83_REG_R_TCRIT 0x42
81 #define LM83_REG_W_TCRIT 0x5A
84 * Conversions and various macros
85 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
88 #define TEMP_FROM_REG(val) ((val) * 1000)
89 #define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \
90 (val) >= 127000 ? 127 : \
91 (val) < 0 ? ((val) - 500) / 1000 : \
94 static const u8 LM83_REG_R_TEMP[] = {
95 LM83_REG_R_LOCAL_TEMP,
96 LM83_REG_R_REMOTE1_TEMP,
97 LM83_REG_R_REMOTE2_TEMP,
98 LM83_REG_R_REMOTE3_TEMP,
99 LM83_REG_R_LOCAL_HIGH,
100 LM83_REG_R_REMOTE1_HIGH,
101 LM83_REG_R_REMOTE2_HIGH,
102 LM83_REG_R_REMOTE3_HIGH,
106 static const u8 LM83_REG_W_HIGH[] = {
107 LM83_REG_W_LOCAL_HIGH,
108 LM83_REG_W_REMOTE1_HIGH,
109 LM83_REG_W_REMOTE2_HIGH,
110 LM83_REG_W_REMOTE3_HIGH,
115 * Functions declaration
118 static int lm83_attach_adapter(struct i2c_adapter *adapter);
119 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind);
120 static int lm83_detach_client(struct i2c_client *client);
121 static struct lm83_data *lm83_update_device(struct device *dev);
124 * Driver data (common to all clients)
127 static struct i2c_driver lm83_driver = {
128 .owner = THIS_MODULE,
130 .id = I2C_DRIVERID_LM83,
131 .flags = I2C_DF_NOTIFY,
132 .attach_adapter = lm83_attach_adapter,
133 .detach_client = lm83_detach_client,
137 * Client data (each client gets its own)
141 struct i2c_client client;
142 struct class_device *class_dev;
143 struct semaphore update_lock;
144 char valid; /* zero until following fields are valid */
145 unsigned long last_updated; /* in jiffies */
147 /* registers values */
148 s8 temp[9]; /* 0..3: input 1-4,
149 4..7: high limit 1-4,
150 8 : critical limit */
151 u16 alarms; /* bitvector, combined */
158 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
161 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
162 struct lm83_data *data = lm83_update_device(dev);
163 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
166 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
167 const char *buf, size_t count)
169 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
170 struct i2c_client *client = to_i2c_client(dev);
171 struct lm83_data *data = i2c_get_clientdata(client);
172 long val = simple_strtol(buf, NULL, 10);
173 int nr = attr->index;
175 down(&data->update_lock);
176 data->temp[nr] = TEMP_TO_REG(val);
177 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
179 up(&data->update_lock);
183 static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
186 struct lm83_data *data = lm83_update_device(dev);
187 return sprintf(buf, "%d\n", data->alarms);
190 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
191 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
192 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
193 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
194 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
196 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
198 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
200 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
202 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
203 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
204 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
206 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
207 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
213 static int lm83_attach_adapter(struct i2c_adapter *adapter)
215 if (!(adapter->class & I2C_CLASS_HWMON))
217 return i2c_detect(adapter, &addr_data, lm83_detect);
221 * The following function does more than just detection. If detection
222 * succeeds, it also registers the new chip.
224 static int lm83_detect(struct i2c_adapter *adapter, int address, int kind)
226 struct i2c_client *new_client;
227 struct lm83_data *data;
229 const char *name = "";
231 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
234 if (!(data = kmalloc(sizeof(struct lm83_data), GFP_KERNEL))) {
238 memset(data, 0, sizeof(struct lm83_data));
240 /* The common I2C client data is placed right after the
241 * LM83-specific data. */
242 new_client = &data->client;
243 i2c_set_clientdata(new_client, data);
244 new_client->addr = address;
245 new_client->adapter = adapter;
246 new_client->driver = &lm83_driver;
247 new_client->flags = 0;
249 /* Now we do the detection and identification. A negative kind
250 * means that the driver was loaded with no force parameter
251 * (default), so we must both detect and identify the chip
252 * (actually there is only one possible kind of chip for now, LM83).
253 * A zero kind means that the driver was loaded with the force
254 * parameter, the detection step shall be skipped. A positive kind
255 * means that the driver was loaded with the force parameter and a
256 * given kind of chip is requested, so both the detection and the
257 * identification steps are skipped. */
259 /* Default to an LM83 if forced */
263 if (kind < 0) { /* detection */
264 if (((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1)
266 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2)
268 ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG)
270 dev_dbg(&adapter->dev,
271 "LM83 detection failed at 0x%02x.\n", address);
276 if (kind <= 0) { /* identification */
279 man_id = i2c_smbus_read_byte_data(new_client,
281 chip_id = i2c_smbus_read_byte_data(new_client,
284 if (man_id == 0x01) { /* National Semiconductor */
285 if (chip_id == 0x03) {
290 if (kind <= 0) { /* identification failed */
291 dev_info(&adapter->dev,
292 "Unsupported chip (man_id=0x%02X, "
293 "chip_id=0x%02X).\n", man_id, chip_id);
302 /* We can fill in the remaining client fields */
303 strlcpy(new_client->name, name, I2C_NAME_SIZE);
305 init_MUTEX(&data->update_lock);
307 /* Tell the I2C layer a new client has arrived */
308 if ((err = i2c_attach_client(new_client)))
312 * Initialize the LM83 chip
313 * (Nothing to do for this one.)
316 /* Register sysfs hooks */
317 data->class_dev = hwmon_device_register(&new_client->dev);
318 if (IS_ERR(data->class_dev)) {
319 err = PTR_ERR(data->class_dev);
323 device_create_file(&new_client->dev,
324 &sensor_dev_attr_temp1_input.dev_attr);
325 device_create_file(&new_client->dev,
326 &sensor_dev_attr_temp2_input.dev_attr);
327 device_create_file(&new_client->dev,
328 &sensor_dev_attr_temp3_input.dev_attr);
329 device_create_file(&new_client->dev,
330 &sensor_dev_attr_temp4_input.dev_attr);
331 device_create_file(&new_client->dev,
332 &sensor_dev_attr_temp1_max.dev_attr);
333 device_create_file(&new_client->dev,
334 &sensor_dev_attr_temp2_max.dev_attr);
335 device_create_file(&new_client->dev,
336 &sensor_dev_attr_temp3_max.dev_attr);
337 device_create_file(&new_client->dev,
338 &sensor_dev_attr_temp4_max.dev_attr);
339 device_create_file(&new_client->dev,
340 &sensor_dev_attr_temp1_crit.dev_attr);
341 device_create_file(&new_client->dev,
342 &sensor_dev_attr_temp2_crit.dev_attr);
343 device_create_file(&new_client->dev,
344 &sensor_dev_attr_temp3_crit.dev_attr);
345 device_create_file(&new_client->dev,
346 &sensor_dev_attr_temp4_crit.dev_attr);
347 device_create_file(&new_client->dev, &dev_attr_alarms);
352 i2c_detach_client(new_client);
359 static int lm83_detach_client(struct i2c_client *client)
361 struct lm83_data *data = i2c_get_clientdata(client);
364 hwmon_device_unregister(data->class_dev);
366 if ((err = i2c_detach_client(client)))
373 static struct lm83_data *lm83_update_device(struct device *dev)
375 struct i2c_client *client = to_i2c_client(dev);
376 struct lm83_data *data = i2c_get_clientdata(client);
378 down(&data->update_lock);
380 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
383 dev_dbg(&client->dev, "Updating lm83 data.\n");
384 for (nr = 0; nr < 9; nr++) {
386 i2c_smbus_read_byte_data(client,
387 LM83_REG_R_TEMP[nr]);
390 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
391 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
394 data->last_updated = jiffies;
398 up(&data->update_lock);
403 static int __init sensors_lm83_init(void)
405 return i2c_add_driver(&lm83_driver);
408 static void __exit sensors_lm83_exit(void)
410 i2c_del_driver(&lm83_driver);
413 MODULE_AUTHOR("Jean Delvare <khali@linux-fr.org>");
414 MODULE_DESCRIPTION("LM83 driver");
415 MODULE_LICENSE("GPL");
417 module_init(sensors_lm83_init);
418 module_exit(sensors_lm83_exit);