1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * lm83.c - Part of lm_sensors, Linux kernel modules for hardware
4 * monitoring
5 * Copyright (C) 2003-2009 Jean Delvare <jdelvare@suse.de>
6 *
7 * Heavily inspired from the lm78, lm75 and adm1021 drivers. The LM83 is
8 * a sensor chip made by National Semiconductor. It reports up to four
9 * temperatures (its own plus up to three external ones) with a 1 deg
10 * resolution and a 3-4 deg accuracy. Complete datasheet can be obtained
11 * from National's website at:
12 * http://www.national.com/pf/LM/LM83.html
13 * Since the datasheet omits to give the chip stepping code, I give it
14 * here: 0x03 (at register 0xff).
15 *
16 * Also supports the LM82 temp sensor, which is basically a stripped down
17 * model of the LM83. Datasheet is here:
18 * http://www.national.com/pf/LM/LM82.html
19 */
20
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/slab.h>
24 #include <linux/jiffies.h>
25 #include <linux/i2c.h>
26 #include <linux/hwmon-sysfs.h>
27 #include <linux/hwmon.h>
28 #include <linux/err.h>
29 #include <linux/mutex.h>
30 #include <linux/sysfs.h>
31
32 /*
33 * Addresses to scan
34 * Address is selected using 2 three-level pins, resulting in 9 possible
35 * addresses.
36 */
37
38 static const unsigned short normal_i2c[] = {
39 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
40
41 enum chips { lm83, lm82 };
42
43 /*
44 * The LM83 registers
45 * Manufacturer ID is 0x01 for National Semiconductor.
46 */
47
48 #define LM83_REG_R_MAN_ID 0xFE
49 #define LM83_REG_R_CHIP_ID 0xFF
50 #define LM83_REG_R_CONFIG 0x03
51 #define LM83_REG_W_CONFIG 0x09
52 #define LM83_REG_R_STATUS1 0x02
53 #define LM83_REG_R_STATUS2 0x35
54 #define LM83_REG_R_LOCAL_TEMP 0x00
55 #define LM83_REG_R_LOCAL_HIGH 0x05
56 #define LM83_REG_W_LOCAL_HIGH 0x0B
57 #define LM83_REG_R_REMOTE1_TEMP 0x30
58 #define LM83_REG_R_REMOTE1_HIGH 0x38
59 #define LM83_REG_W_REMOTE1_HIGH 0x50
60 #define LM83_REG_R_REMOTE2_TEMP 0x01
61 #define LM83_REG_R_REMOTE2_HIGH 0x07
62 #define LM83_REG_W_REMOTE2_HIGH 0x0D
63 #define LM83_REG_R_REMOTE3_TEMP 0x31
64 #define LM83_REG_R_REMOTE3_HIGH 0x3A
65 #define LM83_REG_W_REMOTE3_HIGH 0x52
66 #define LM83_REG_R_TCRIT 0x42
67 #define LM83_REG_W_TCRIT 0x5A
68
69 /*
70 * Conversions and various macros
71 * The LM83 uses signed 8-bit values with LSB = 1 degree Celsius.
72 */
73
74 #define TEMP_FROM_REG(val) ((val) * 1000)
75 #define TEMP_TO_REG(val) ((val) <= -128000 ? -128 : \
76 (val) >= 127000 ? 127 : \
77 (val) < 0 ? ((val) - 500) / 1000 : \
78 ((val) + 500) / 1000)
79
80 static const u8 LM83_REG_R_TEMP[] = {
81 LM83_REG_R_LOCAL_TEMP,
82 LM83_REG_R_REMOTE1_TEMP,
83 LM83_REG_R_REMOTE2_TEMP,
84 LM83_REG_R_REMOTE3_TEMP,
85 LM83_REG_R_LOCAL_HIGH,
86 LM83_REG_R_REMOTE1_HIGH,
87 LM83_REG_R_REMOTE2_HIGH,
88 LM83_REG_R_REMOTE3_HIGH,
89 LM83_REG_R_TCRIT,
90 };
91
92 static const u8 LM83_REG_W_HIGH[] = {
93 LM83_REG_W_LOCAL_HIGH,
94 LM83_REG_W_REMOTE1_HIGH,
95 LM83_REG_W_REMOTE2_HIGH,
96 LM83_REG_W_REMOTE3_HIGH,
97 LM83_REG_W_TCRIT,
98 };
99
100 /*
101 * Client data (each client gets its own)
102 */
103
104 struct lm83_data {
105 struct i2c_client *client;
106 const struct attribute_group *groups[3];
107 struct mutex update_lock;
108 char valid; /* zero until following fields are valid */
109 unsigned long last_updated; /* in jiffies */
110
111 /* registers values */
112 s8 temp[9]; /* 0..3: input 1-4,
113 4..7: high limit 1-4,
114 8 : critical limit */
115 u16 alarms; /* bitvector, combined */
116 };
117
lm83_update_device(struct device * dev)118 static struct lm83_data *lm83_update_device(struct device *dev)
119 {
120 struct lm83_data *data = dev_get_drvdata(dev);
121 struct i2c_client *client = data->client;
122
123 mutex_lock(&data->update_lock);
124
125 if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
126 int nr;
127
128 dev_dbg(&client->dev, "Updating lm83 data.\n");
129 for (nr = 0; nr < 9; nr++) {
130 data->temp[nr] =
131 i2c_smbus_read_byte_data(client,
132 LM83_REG_R_TEMP[nr]);
133 }
134 data->alarms =
135 i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS1)
136 + (i2c_smbus_read_byte_data(client, LM83_REG_R_STATUS2)
137 << 8);
138
139 data->last_updated = jiffies;
140 data->valid = 1;
141 }
142
143 mutex_unlock(&data->update_lock);
144
145 return data;
146 }
147
148 /*
149 * Sysfs stuff
150 */
151
temp_show(struct device * dev,struct device_attribute * devattr,char * buf)152 static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
153 char *buf)
154 {
155 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
156 struct lm83_data *data = lm83_update_device(dev);
157 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[attr->index]));
158 }
159
temp_store(struct device * dev,struct device_attribute * devattr,const char * buf,size_t count)160 static ssize_t temp_store(struct device *dev,
161 struct device_attribute *devattr, const char *buf,
162 size_t count)
163 {
164 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
165 struct lm83_data *data = dev_get_drvdata(dev);
166 struct i2c_client *client = data->client;
167 long val;
168 int nr = attr->index;
169 int err;
170
171 err = kstrtol(buf, 10, &val);
172 if (err < 0)
173 return err;
174
175 mutex_lock(&data->update_lock);
176 data->temp[nr] = TEMP_TO_REG(val);
177 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
178 data->temp[nr]);
179 mutex_unlock(&data->update_lock);
180 return count;
181 }
182
alarms_show(struct device * dev,struct device_attribute * dummy,char * buf)183 static ssize_t alarms_show(struct device *dev, struct device_attribute *dummy,
184 char *buf)
185 {
186 struct lm83_data *data = lm83_update_device(dev);
187 return sprintf(buf, "%d\n", data->alarms);
188 }
189
alarm_show(struct device * dev,struct device_attribute * devattr,char * buf)190 static ssize_t alarm_show(struct device *dev,
191 struct device_attribute *devattr, char *buf)
192 {
193 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
194 struct lm83_data *data = lm83_update_device(dev);
195 int bitnr = attr->index;
196
197 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
198 }
199
200 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
201 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
202 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
203 static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3);
204 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, 4);
205 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, 5);
206 static SENSOR_DEVICE_ATTR_RW(temp3_max, temp, 6);
207 static SENSOR_DEVICE_ATTR_RW(temp4_max, temp, 7);
208 static SENSOR_DEVICE_ATTR_RO(temp1_crit, temp, 8);
209 static SENSOR_DEVICE_ATTR_RO(temp2_crit, temp, 8);
210 static SENSOR_DEVICE_ATTR_RW(temp3_crit, temp, 8);
211 static SENSOR_DEVICE_ATTR_RO(temp4_crit, temp, 8);
212
213 /* Individual alarm files */
214 static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 0);
215 static SENSOR_DEVICE_ATTR_RO(temp3_crit_alarm, alarm, 1);
216 static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 2);
217 static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, alarm, 4);
218 static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 6);
219 static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 8);
220 static SENSOR_DEVICE_ATTR_RO(temp4_crit_alarm, alarm, 9);
221 static SENSOR_DEVICE_ATTR_RO(temp4_fault, alarm, 10);
222 static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, alarm, 12);
223 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 13);
224 static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 15);
225 /* Raw alarm file for compatibility */
226 static DEVICE_ATTR_RO(alarms);
227
228 static struct attribute *lm83_attributes[] = {
229 &sensor_dev_attr_temp1_input.dev_attr.attr,
230 &sensor_dev_attr_temp3_input.dev_attr.attr,
231 &sensor_dev_attr_temp1_max.dev_attr.attr,
232 &sensor_dev_attr_temp3_max.dev_attr.attr,
233 &sensor_dev_attr_temp1_crit.dev_attr.attr,
234 &sensor_dev_attr_temp3_crit.dev_attr.attr,
235
236 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
237 &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
238 &sensor_dev_attr_temp3_fault.dev_attr.attr,
239 &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
240 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
241 &dev_attr_alarms.attr,
242 NULL
243 };
244
245 static const struct attribute_group lm83_group = {
246 .attrs = lm83_attributes,
247 };
248
249 static struct attribute *lm83_attributes_opt[] = {
250 &sensor_dev_attr_temp2_input.dev_attr.attr,
251 &sensor_dev_attr_temp4_input.dev_attr.attr,
252 &sensor_dev_attr_temp2_max.dev_attr.attr,
253 &sensor_dev_attr_temp4_max.dev_attr.attr,
254 &sensor_dev_attr_temp2_crit.dev_attr.attr,
255 &sensor_dev_attr_temp4_crit.dev_attr.attr,
256
257 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
258 &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
259 &sensor_dev_attr_temp4_fault.dev_attr.attr,
260 &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
261 &sensor_dev_attr_temp2_fault.dev_attr.attr,
262 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
263 NULL
264 };
265
266 static const struct attribute_group lm83_group_opt = {
267 .attrs = lm83_attributes_opt,
268 };
269
270 /*
271 * Real code
272 */
273
274 /* Return 0 if detection is successful, -ENODEV otherwise */
lm83_detect(struct i2c_client * new_client,struct i2c_board_info * info)275 static int lm83_detect(struct i2c_client *new_client,
276 struct i2c_board_info *info)
277 {
278 struct i2c_adapter *adapter = new_client->adapter;
279 const char *name;
280 u8 man_id, chip_id;
281
282 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
283 return -ENODEV;
284
285 /* Detection */
286 if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) ||
287 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) ||
288 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) {
289 dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n",
290 new_client->addr);
291 return -ENODEV;
292 }
293
294 /* Identification */
295 man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID);
296 if (man_id != 0x01) /* National Semiconductor */
297 return -ENODEV;
298
299 chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID);
300 switch (chip_id) {
301 case 0x03:
302 name = "lm83";
303 break;
304 case 0x01:
305 name = "lm82";
306 break;
307 default:
308 /* identification failed */
309 dev_info(&adapter->dev,
310 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n",
311 man_id, chip_id);
312 return -ENODEV;
313 }
314
315 strlcpy(info->type, name, I2C_NAME_SIZE);
316
317 return 0;
318 }
319
320 static const struct i2c_device_id lm83_id[];
321
lm83_probe(struct i2c_client * new_client)322 static int lm83_probe(struct i2c_client *new_client)
323 {
324 struct device *hwmon_dev;
325 struct lm83_data *data;
326
327 data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data),
328 GFP_KERNEL);
329 if (!data)
330 return -ENOMEM;
331
332 data->client = new_client;
333 mutex_init(&data->update_lock);
334
335 /*
336 * Register sysfs hooks
337 * The LM82 can only monitor one external diode which is
338 * at the same register as the LM83 temp3 entry - so we
339 * declare 1 and 3 common, and then 2 and 4 only for the LM83.
340 */
341 data->groups[0] = &lm83_group;
342 if (i2c_match_id(lm83_id, new_client)->driver_data == lm83)
343 data->groups[1] = &lm83_group_opt;
344
345 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
346 new_client->name,
347 data, data->groups);
348 return PTR_ERR_OR_ZERO(hwmon_dev);
349 }
350
351 /*
352 * Driver data (common to all clients)
353 */
354
355 static const struct i2c_device_id lm83_id[] = {
356 { "lm83", lm83 },
357 { "lm82", lm82 },
358 { }
359 };
360 MODULE_DEVICE_TABLE(i2c, lm83_id);
361
362 static struct i2c_driver lm83_driver = {
363 .class = I2C_CLASS_HWMON,
364 .driver = {
365 .name = "lm83",
366 },
367 .probe_new = lm83_probe,
368 .id_table = lm83_id,
369 .detect = lm83_detect,
370 .address_list = normal_i2c,
371 };
372
373 module_i2c_driver(lm83_driver);
374
375 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
376 MODULE_DESCRIPTION("LM83 driver");
377 MODULE_LICENSE("GPL");
378