1 /*
2 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring
4 * Copyright (C) 2003-2009 Jean Delvare <jdelvare@suse.de>
5 *
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).
14 *
15 * Also supports the LM82 temp sensor, which is basically a stripped down
16 * model of the LM83. Datasheet is here:
17 * http://www.national.com/pf/LM/LM82.html
18 *
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation; either version 2 of the License, or
22 * (at your option) any later version.
23 *
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
28 */
29
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/hwmon-sysfs.h>
36 #include <linux/hwmon.h>
37 #include <linux/err.h>
38 #include <linux/mutex.h>
39 #include <linux/sysfs.h>
40
41 /*
42 * Addresses to scan
43 * Address is selected using 2 three-level pins, resulting in 9 possible
44 * addresses.
45 */
46
47 static const unsigned short normal_i2c[] = {
48 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
49
50 enum chips { lm83, lm82 };
51
52 /*
53 * The LM83 registers
54 * Manufacturer ID is 0x01 for National Semiconductor.
55 */
56
57 #define LM83_REG_R_MAN_ID 0xFE
58 #define LM83_REG_R_CHIP_ID 0xFF
59 #define LM83_REG_R_CONFIG 0x03
60 #define LM83_REG_W_CONFIG 0x09
61 #define LM83_REG_R_STATUS1 0x02
62 #define LM83_REG_R_STATUS2 0x35
63 #define LM83_REG_R_LOCAL_TEMP 0x00
64 #define LM83_REG_R_LOCAL_HIGH 0x05
65 #define LM83_REG_W_LOCAL_HIGH 0x0B
66 #define LM83_REG_R_REMOTE1_TEMP 0x30
67 #define LM83_REG_R_REMOTE1_HIGH 0x38
68 #define LM83_REG_W_REMOTE1_HIGH 0x50
69 #define LM83_REG_R_REMOTE2_TEMP 0x01
70 #define LM83_REG_R_REMOTE2_HIGH 0x07
71 #define LM83_REG_W_REMOTE2_HIGH 0x0D
72 #define LM83_REG_R_REMOTE3_TEMP 0x31
73 #define LM83_REG_R_REMOTE3_HIGH 0x3A
74 #define LM83_REG_W_REMOTE3_HIGH 0x52
75 #define LM83_REG_R_TCRIT 0x42
76 #define LM83_REG_W_TCRIT 0x5A
77
78 /*
79 * Conversions and various macros
80 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
81 */
82
83 #define TEMP_FROM_REG(val) ((val) * 1000)
84 #define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \
85 (val) >= 127000 ? 127 : \
86 (val) < 0 ? ((val) - 500) / 1000 : \
87 ((val) + 500) / 1000)
88
89 static const u8 LM83_REG_R_TEMP[] = {
90 LM83_REG_R_LOCAL_TEMP,
91 LM83_REG_R_REMOTE1_TEMP,
92 LM83_REG_R_REMOTE2_TEMP,
93 LM83_REG_R_REMOTE3_TEMP,
94 LM83_REG_R_LOCAL_HIGH,
95 LM83_REG_R_REMOTE1_HIGH,
96 LM83_REG_R_REMOTE2_HIGH,
97 LM83_REG_R_REMOTE3_HIGH,
98 LM83_REG_R_TCRIT,
99 };
100
101 static const u8 LM83_REG_W_HIGH[] = {
102 LM83_REG_W_LOCAL_HIGH,
103 LM83_REG_W_REMOTE1_HIGH,
104 LM83_REG_W_REMOTE2_HIGH,
105 LM83_REG_W_REMOTE3_HIGH,
106 LM83_REG_W_TCRIT,
107 };
108
109 /*
110 * Client data (each client gets its own)
111 */
112
113 struct lm83_data {
114 struct i2c_client *client;
115 const struct attribute_group *groups[3];
116 struct mutex update_lock;
117 char valid; /* zero until following fields are valid */
118 unsigned long last_updated; /* in jiffies */
119
120 /* registers values */
121 s8 temp[9]; /* 0..3: input 1-4,
122 4..7: high limit 1-4,
123 8 : critical limit */
124 u16 alarms; /* bitvector, combined */
125 };
126
lm83_update_device(struct device * dev)127 static struct lm83_data *lm83_update_device(struct device *dev)
128 {
129 struct lm83_data *data = dev_get_drvdata(dev);
130 struct i2c_client *client = data->client;
131
132 mutex_lock(&data->update_lock);
133
134 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
135 int nr;
136
137 dev_dbg(&client->dev, "Updating lm83 data.\n");
138 for (nr = 0; nr < 9; nr++) {
139 data->temp[nr] =
140 i2c_smbus_read_byte_data(client,
141 LM83_REG_R_TEMP[nr]);
142 }
143 data->alarms =
144 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
145 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
146 << 8);
147
148 data->last_updated = jiffies;
149 data->valid = 1;
150 }
151
152 mutex_unlock(&data->update_lock);
153
154 return data;
155 }
156
157 /*
158 * Sysfs stuff
159 */
160
show_temp(struct device * dev,struct device_attribute * devattr,char * buf)161 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
162 char *buf)
163 {
164 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
165 struct lm83_data *data = lm83_update_device(dev);
166 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
167 }
168
set_temp(struct device * dev,struct device_attribute * devattr,const char * buf,size_t count)169 static ssize_t set_temp(struct device *dev, struct device_attribute *devattr,
170 const char *buf, size_t count)
171 {
172 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
173 struct lm83_data *data = dev_get_drvdata(dev);
174 struct i2c_client *client = data->client;
175 long val;
176 int nr = attr->index;
177 int err;
178
179 err = kstrtol(buf, 10, &val);
180 if (err < 0)
181 return err;
182
183 mutex_lock(&data->update_lock);
184 data->temp[nr] = TEMP_TO_REG(val);
185 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
186 data->temp[nr]);
187 mutex_unlock(&data->update_lock);
188 return count;
189 }
190
alarms_show(struct device * dev,struct device_attribute * dummy,char * buf)191 static ssize_t alarms_show(struct device *dev, struct device_attribute *dummy,
192 char *buf)
193 {
194 struct lm83_data *data = lm83_update_device(dev);
195 return sprintf(buf, "%d\n", data->alarms);
196 }
197
show_alarm(struct device * dev,struct device_attribute * devattr,char * buf)198 static ssize_t show_alarm(struct device *dev, struct device_attribute
199 *devattr, char *buf)
200 {
201 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
202 struct lm83_data *data = lm83_update_device(dev);
203 int bitnr = attr->index;
204
205 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
206 }
207
208 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
209 static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
210 static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
211 static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
212 static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp,
213 set_temp, 4);
214 static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp,
215 set_temp, 5);
216 static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_temp,
217 set_temp, 6);
218 static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_temp,
219 set_temp, 7);
220 static SENSOR_DEVICE_ATTR(temp1_crit, S_IRUGO, show_temp, NULL, 8);
221 static SENSOR_DEVICE_ATTR(temp2_crit, S_IRUGO, show_temp, NULL, 8);
222 static SENSOR_DEVICE_ATTR(temp3_crit, S_IWUSR | S_IRUGO, show_temp,
223 set_temp, 8);
224 static SENSOR_DEVICE_ATTR(temp4_crit, S_IRUGO, show_temp, NULL, 8);
225
226 /* Individual alarm files */
227 static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 0);
228 static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
229 static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 2);
230 static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_alarm, NULL, 4);
231 static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_alarm, NULL, 6);
232 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 8);
233 static SENSOR_DEVICE_ATTR(temp4_crit_alarm, S_IRUGO, show_alarm, NULL, 9);
234 static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_alarm, NULL, 10);
235 static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_alarm, NULL, 12);
236 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 13);
237 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 15);
238 /* Raw alarm file for compatibility */
239 static DEVICE_ATTR_RO(alarms);
240
241 static struct attribute *lm83_attributes[] = {
242 &sensor_dev_attr_temp1_input.dev_attr.attr,
243 &sensor_dev_attr_temp3_input.dev_attr.attr,
244 &sensor_dev_attr_temp1_max.dev_attr.attr,
245 &sensor_dev_attr_temp3_max.dev_attr.attr,
246 &sensor_dev_attr_temp1_crit.dev_attr.attr,
247 &sensor_dev_attr_temp3_crit.dev_attr.attr,
248
249 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
250 &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
251 &sensor_dev_attr_temp3_fault.dev_attr.attr,
252 &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
253 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
254 &dev_attr_alarms.attr,
255 NULL
256 };
257
258 static const struct attribute_group lm83_group = {
259 .attrs = lm83_attributes,
260 };
261
262 static struct attribute *lm83_attributes_opt[] = {
263 &sensor_dev_attr_temp2_input.dev_attr.attr,
264 &sensor_dev_attr_temp4_input.dev_attr.attr,
265 &sensor_dev_attr_temp2_max.dev_attr.attr,
266 &sensor_dev_attr_temp4_max.dev_attr.attr,
267 &sensor_dev_attr_temp2_crit.dev_attr.attr,
268 &sensor_dev_attr_temp4_crit.dev_attr.attr,
269
270 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
271 &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
272 &sensor_dev_attr_temp4_fault.dev_attr.attr,
273 &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
274 &sensor_dev_attr_temp2_fault.dev_attr.attr,
275 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
276 NULL
277 };
278
279 static const struct attribute_group lm83_group_opt = {
280 .attrs = lm83_attributes_opt,
281 };
282
283 /*
284 * Real code
285 */
286
287 /* Return 0 if detection is successful, -ENODEV otherwise */
lm83_detect(struct i2c_client * new_client,struct i2c_board_info * info)288 static int lm83_detect(struct i2c_client *new_client,
289 struct i2c_board_info *info)
290 {
291 struct i2c_adapter *adapter = new_client->adapter;
292 const char *name;
293 u8 man_id, chip_id;
294
295 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
296 return -ENODEV;
297
298 /* Detection */
299 if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) ||
300 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) ||
301 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) {
302 dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n",
303 new_client->addr);
304 return -ENODEV;
305 }
306
307 /* Identification */
308 man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID);
309 if (man_id != 0x01) /* National Semiconductor */
310 return -ENODEV;
311
312 chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID);
313 switch (chip_id) {
314 case 0x03:
315 name = "lm83";
316 break;
317 case 0x01:
318 name = "lm82";
319 break;
320 default:
321 /* identification failed */
322 dev_info(&adapter->dev,
323 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n",
324 man_id, chip_id);
325 return -ENODEV;
326 }
327
328 strlcpy(info->type, name, I2C_NAME_SIZE);
329
330 return 0;
331 }
332
lm83_probe(struct i2c_client * new_client,const struct i2c_device_id * id)333 static int lm83_probe(struct i2c_client *new_client,
334 const struct i2c_device_id *id)
335 {
336 struct device *hwmon_dev;
337 struct lm83_data *data;
338
339 data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data),
340 GFP_KERNEL);
341 if (!data)
342 return -ENOMEM;
343
344 data->client = new_client;
345 mutex_init(&data->update_lock);
346
347 /*
348 * Register sysfs hooks
349 * The LM82 can only monitor one external diode which is
350 * at the same register as the LM83 temp3 entry - so we
351 * declare 1 and 3 common, and then 2 and 4 only for the LM83.
352 */
353 data->groups[0] = &lm83_group;
354 if (id->driver_data == lm83)
355 data->groups[1] = &lm83_group_opt;
356
357 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
358 new_client->name,
359 data, data->groups);
360 return PTR_ERR_OR_ZERO(hwmon_dev);
361 }
362
363 /*
364 * Driver data (common to all clients)
365 */
366
367 static const struct i2c_device_id lm83_id[] = {
368 { "lm83", lm83 },
369 { "lm82", lm82 },
370 { }
371 };
372 MODULE_DEVICE_TABLE(i2c, lm83_id);
373
374 static struct i2c_driver lm83_driver = {
375 .class = I2C_CLASS_HWMON,
376 .driver = {
377 .name = "lm83",
378 },
379 .probe = lm83_probe,
380 .id_table = lm83_id,
381 .detect = lm83_detect,
382 .address_list = normal_i2c,
383 };
384
385 module_i2c_driver(lm83_driver);
386
387 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
388 MODULE_DESCRIPTION("LM83 driver");
389 MODULE_LICENSE("GPL");
390
