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
47static const unsigned short normal_i2c[] = {
48 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
49
50enum 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
89static 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
101static 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
113struct 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
127static 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
161static ssize_t temp_show(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
169static ssize_t temp_store(struct device *dev,
170 struct device_attribute *devattr, const char *buf,
171 size_t count)
172{
173 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
174 struct lm83_data *data = dev_get_drvdata(dev);
175 struct i2c_client *client = data->client;
176 long val;
177 int nr = attr->index;
178 int err;
179
180 err = kstrtol(buf, 10, &val);
181 if (err < 0)
182 return err;
183
184 mutex_lock(&data->update_lock);
185 data->temp[nr] = TEMP_TO_REG(val);
186 i2c_smbus_write_byte_data(client, LM83_REG_W_HIGH[nr - 4],
187 data->temp[nr]);
188 mutex_unlock(&data->update_lock);
189 return count;
190}
191
192static ssize_t alarms_show(struct device *dev, struct device_attribute *dummy,
193 char *buf)
194{
195 struct lm83_data *data = lm83_update_device(dev);
196 return sprintf(buf, "%d\n", data->alarms);
197}
198
199static ssize_t alarm_show(struct device *dev,
200 struct device_attribute *devattr, char *buf)
201{
202 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
203 struct lm83_data *data = lm83_update_device(dev);
204 int bitnr = attr->index;
205
206 return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
207}
208
209static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
210static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
211static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
212static SENSOR_DEVICE_ATTR_RO(temp4_input, temp, 3);
213static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, 4);
214static SENSOR_DEVICE_ATTR_RW(temp2_max, temp, 5);
215static SENSOR_DEVICE_ATTR_RW(temp3_max, temp, 6);
216static SENSOR_DEVICE_ATTR_RW(temp4_max, temp, 7);
217static SENSOR_DEVICE_ATTR_RO(temp1_crit, temp, 8);
218static SENSOR_DEVICE_ATTR_RO(temp2_crit, temp, 8);
219static SENSOR_DEVICE_ATTR_RW(temp3_crit, temp, 8);
220static SENSOR_DEVICE_ATTR_RO(temp4_crit, temp, 8);
221
222/* Individual alarm files */
223static SENSOR_DEVICE_ATTR_RO(temp1_crit_alarm, alarm, 0);
224static SENSOR_DEVICE_ATTR_RO(temp3_crit_alarm, alarm, 1);
225static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 2);
226static SENSOR_DEVICE_ATTR_RO(temp3_max_alarm, alarm, 4);
227static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 6);
228static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, alarm, 8);
229static SENSOR_DEVICE_ATTR_RO(temp4_crit_alarm, alarm, 9);
230static SENSOR_DEVICE_ATTR_RO(temp4_fault, alarm, 10);
231static SENSOR_DEVICE_ATTR_RO(temp4_max_alarm, alarm, 12);
232static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 13);
233static SENSOR_DEVICE_ATTR_RO(temp2_max_alarm, alarm, 15);
234/* Raw alarm file for compatibility */
235static DEVICE_ATTR_RO(alarms);
236
237static struct attribute *lm83_attributes[] = {
238 &sensor_dev_attr_temp1_input.dev_attr.attr,
239 &sensor_dev_attr_temp3_input.dev_attr.attr,
240 &sensor_dev_attr_temp1_max.dev_attr.attr,
241 &sensor_dev_attr_temp3_max.dev_attr.attr,
242 &sensor_dev_attr_temp1_crit.dev_attr.attr,
243 &sensor_dev_attr_temp3_crit.dev_attr.attr,
244
245 &sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
246 &sensor_dev_attr_temp3_crit_alarm.dev_attr.attr,
247 &sensor_dev_attr_temp3_fault.dev_attr.attr,
248 &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
249 &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
250 &dev_attr_alarms.attr,
251 NULL
252};
253
254static const struct attribute_group lm83_group = {
255 .attrs = lm83_attributes,
256};
257
258static struct attribute *lm83_attributes_opt[] = {
259 &sensor_dev_attr_temp2_input.dev_attr.attr,
260 &sensor_dev_attr_temp4_input.dev_attr.attr,
261 &sensor_dev_attr_temp2_max.dev_attr.attr,
262 &sensor_dev_attr_temp4_max.dev_attr.attr,
263 &sensor_dev_attr_temp2_crit.dev_attr.attr,
264 &sensor_dev_attr_temp4_crit.dev_attr.attr,
265
266 &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
267 &sensor_dev_attr_temp4_crit_alarm.dev_attr.attr,
268 &sensor_dev_attr_temp4_fault.dev_attr.attr,
269 &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
270 &sensor_dev_attr_temp2_fault.dev_attr.attr,
271 &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
272 NULL
273};
274
275static const struct attribute_group lm83_group_opt = {
276 .attrs = lm83_attributes_opt,
277};
278
279/*
280 * Real code
281 */
282
283/* Return 0 if detection is successful, -ENODEV otherwise */
284static int lm83_detect(struct i2c_client *new_client,
285 struct i2c_board_info *info)
286{
287 struct i2c_adapter *adapter = new_client->adapter;
288 const char *name;
289 u8 man_id, chip_id;
290
291 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
292 return -ENODEV;
293
294 /* Detection */
295 if ((i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS1) & 0xA8) ||
296 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_STATUS2) & 0x48) ||
297 (i2c_smbus_read_byte_data(new_client, LM83_REG_R_CONFIG) & 0x41)) {
298 dev_dbg(&adapter->dev, "LM83 detection failed at 0x%02x\n",
299 new_client->addr);
300 return -ENODEV;
301 }
302
303 /* Identification */
304 man_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_MAN_ID);
305 if (man_id != 0x01) /* National Semiconductor */
306 return -ENODEV;
307
308 chip_id = i2c_smbus_read_byte_data(new_client, LM83_REG_R_CHIP_ID);
309 switch (chip_id) {
310 case 0x03:
311 name = "lm83";
312 break;
313 case 0x01:
314 name = "lm82";
315 break;
316 default:
317 /* identification failed */
318 dev_info(&adapter->dev,
319 "Unsupported chip (man_id=0x%02X, chip_id=0x%02X)\n",
320 man_id, chip_id);
321 return -ENODEV;
322 }
323
324 strlcpy(info->type, name, I2C_NAME_SIZE);
325
326 return 0;
327}
328
329static int lm83_probe(struct i2c_client *new_client,
330 const struct i2c_device_id *id)
331{
332 struct device *hwmon_dev;
333 struct lm83_data *data;
334
335 data = devm_kzalloc(&new_client->dev, sizeof(struct lm83_data),
336 GFP_KERNEL);
337 if (!data)
338 return -ENOMEM;
339
340 data->client = new_client;
341 mutex_init(&data->update_lock);
342
343 /*
344 * Register sysfs hooks
345 * The LM82 can only monitor one external diode which is
346 * at the same register as the LM83 temp3 entry - so we
347 * declare 1 and 3 common, and then 2 and 4 only for the LM83.
348 */
349 data->groups[0] = &lm83_group;
350 if (id->driver_data == lm83)
351 data->groups[1] = &lm83_group_opt;
352
353 hwmon_dev = devm_hwmon_device_register_with_groups(&new_client->dev,
354 new_client->name,
355 data, data->groups);
356 return PTR_ERR_OR_ZERO(hwmon_dev);
357}
358
359/*
360 * Driver data (common to all clients)
361 */
362
363static const struct i2c_device_id lm83_id[] = {
364 { "lm83", lm83 },
365 { "lm82", lm82 },
366 { }
367};
368MODULE_DEVICE_TABLE(i2c, lm83_id);
369
370static struct i2c_driver lm83_driver = {
371 .class = I2C_CLASS_HWMON,
372 .driver = {
373 .name = "lm83",
374 },
375 .probe = lm83_probe,
376 .id_table = lm83_id,
377 .detect = lm83_detect,
378 .address_list = normal_i2c,
379};
380
381module_i2c_driver(lm83_driver);
382
383MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
384MODULE_DESCRIPTION("LM83 driver");
385MODULE_LICENSE("GPL");
386