Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
caaa0f36 S |
2 | * lm75.c - Part of lm_sensors, Linux kernel modules for hardware |
3 | * monitoring | |
4 | * Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
19 | */ | |
1da177e4 | 20 | |
1da177e4 LT |
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> | |
943b0830 | 26 | #include <linux/hwmon.h> |
9ca8e40c | 27 | #include <linux/hwmon-sysfs.h> |
943b0830 | 28 | #include <linux/err.h> |
9a61bf63 | 29 | #include <linux/mutex.h> |
22e73183 EV |
30 | #include <linux/of.h> |
31 | #include <linux/thermal.h> | |
1da177e4 LT |
32 | #include "lm75.h" |
33 | ||
34 | ||
01a52397 DB |
35 | /* |
36 | * This driver handles the LM75 and compatible digital temperature sensors. | |
01a52397 DB |
37 | */ |
38 | ||
9ebd3d82 | 39 | enum lm75_type { /* keep sorted in alphabetical order */ |
e96f9d89 | 40 | adt75, |
1f86df49 | 41 | ds1775, |
9ebd3d82 | 42 | ds75, |
3fbc81e3 | 43 | ds7505, |
c98d6c65 | 44 | g751, |
1f86df49 | 45 | lm75, |
9ebd3d82 | 46 | lm75a, |
799fc602 | 47 | lm75b, |
9ebd3d82 DB |
48 | max6625, |
49 | max6626, | |
50 | mcp980x, | |
51 | stds75, | |
52 | tcn75, | |
53 | tmp100, | |
54 | tmp101, | |
6d034059 | 55 | tmp105, |
c83959f8 | 56 | tmp112, |
9ebd3d82 DB |
57 | tmp175, |
58 | tmp275, | |
59 | tmp75, | |
60 | }; | |
61 | ||
8ff69eeb | 62 | /* Addresses scanned */ |
25e9c86d | 63 | static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c, |
1da177e4 | 64 | 0x4d, 0x4e, 0x4f, I2C_CLIENT_END }; |
1da177e4 | 65 | |
1da177e4 LT |
66 | |
67 | /* The LM75 registers */ | |
1da177e4 | 68 | #define LM75_REG_CONF 0x01 |
9ca8e40c JD |
69 | static const u8 LM75_REG_TEMP[3] = { |
70 | 0x00, /* input */ | |
71 | 0x03, /* max */ | |
72 | 0x02, /* hyst */ | |
73 | }; | |
1da177e4 LT |
74 | |
75 | /* Each client has this additional data */ | |
76 | struct lm75_data { | |
d663ec49 | 77 | struct i2c_client *client; |
01a52397 | 78 | struct device *hwmon_dev; |
22e73183 | 79 | struct thermal_zone_device *tz; |
9a61bf63 | 80 | struct mutex update_lock; |
9ebd3d82 | 81 | u8 orig_conf; |
87d0621a JD |
82 | u8 resolution; /* In bits, between 9 and 12 */ |
83 | u8 resolution_limits; | |
01a52397 | 84 | char valid; /* !=0 if registers are valid */ |
1da177e4 | 85 | unsigned long last_updated; /* In jiffies */ |
87d0621a JD |
86 | unsigned long sample_time; /* In jiffies */ |
87 | s16 temp[3]; /* Register values, | |
9ca8e40c JD |
88 | 0 = input |
89 | 1 = max | |
90 | 2 = hyst */ | |
1da177e4 LT |
91 | }; |
92 | ||
1da177e4 LT |
93 | static int lm75_read_value(struct i2c_client *client, u8 reg); |
94 | static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value); | |
95 | static struct lm75_data *lm75_update_device(struct device *dev); | |
96 | ||
97 | ||
01a52397 DB |
98 | /*-----------------------------------------------------------------------*/ |
99 | ||
22e73183 EV |
100 | static inline long lm75_reg_to_mc(s16 temp, u8 resolution) |
101 | { | |
102 | return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8); | |
103 | } | |
104 | ||
01a52397 | 105 | /* sysfs attributes for hwmon */ |
1da177e4 | 106 | |
17e8351a | 107 | static int lm75_read_temp(void *dev, int *temp) |
22e73183 EV |
108 | { |
109 | struct lm75_data *data = lm75_update_device(dev); | |
110 | ||
111 | if (IS_ERR(data)) | |
112 | return PTR_ERR(data); | |
113 | ||
114 | *temp = lm75_reg_to_mc(data->temp[0], data->resolution); | |
115 | ||
116 | return 0; | |
117 | } | |
118 | ||
9ca8e40c JD |
119 | static ssize_t show_temp(struct device *dev, struct device_attribute *da, |
120 | char *buf) | |
121 | { | |
122 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); | |
123 | struct lm75_data *data = lm75_update_device(dev); | |
1f962f36 FM |
124 | |
125 | if (IS_ERR(data)) | |
126 | return PTR_ERR(data); | |
127 | ||
22e73183 EV |
128 | return sprintf(buf, "%ld\n", lm75_reg_to_mc(data->temp[attr->index], |
129 | data->resolution)); | |
1da177e4 | 130 | } |
9ca8e40c JD |
131 | |
132 | static ssize_t set_temp(struct device *dev, struct device_attribute *da, | |
133 | const char *buf, size_t count) | |
134 | { | |
135 | struct sensor_device_attribute *attr = to_sensor_dev_attr(da); | |
d663ec49 GR |
136 | struct lm75_data *data = dev_get_drvdata(dev); |
137 | struct i2c_client *client = data->client; | |
9ca8e40c | 138 | int nr = attr->index; |
e3cd9528 S |
139 | long temp; |
140 | int error; | |
87d0621a | 141 | u8 resolution; |
e3cd9528 | 142 | |
24edc0a7 | 143 | error = kstrtol(buf, 10, &temp); |
e3cd9528 S |
144 | if (error) |
145 | return error; | |
9ca8e40c | 146 | |
87d0621a JD |
147 | /* |
148 | * Resolution of limit registers is assumed to be the same as the | |
149 | * temperature input register resolution unless given explicitly. | |
150 | */ | |
151 | if (attr->index && data->resolution_limits) | |
152 | resolution = data->resolution_limits; | |
153 | else | |
154 | resolution = data->resolution; | |
155 | ||
9ca8e40c | 156 | mutex_lock(&data->update_lock); |
87d0621a JD |
157 | temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX); |
158 | data->temp[nr] = DIV_ROUND_CLOSEST(temp << (resolution - 8), | |
159 | 1000) << (16 - resolution); | |
9ca8e40c JD |
160 | lm75_write_value(client, LM75_REG_TEMP[nr], data->temp[nr]); |
161 | mutex_unlock(&data->update_lock); | |
162 | return count; | |
1da177e4 | 163 | } |
1da177e4 | 164 | |
9ca8e40c JD |
165 | static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, |
166 | show_temp, set_temp, 1); | |
167 | static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, | |
168 | show_temp, set_temp, 2); | |
169 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0); | |
1da177e4 | 170 | |
d663ec49 | 171 | static struct attribute *lm75_attrs[] = { |
9ca8e40c JD |
172 | &sensor_dev_attr_temp1_input.dev_attr.attr, |
173 | &sensor_dev_attr_temp1_max.dev_attr.attr, | |
174 | &sensor_dev_attr_temp1_max_hyst.dev_attr.attr, | |
c1685f61 MH |
175 | |
176 | NULL | |
177 | }; | |
d663ec49 | 178 | ATTRIBUTE_GROUPS(lm75); |
c1685f61 | 179 | |
2251aef6 EV |
180 | static const struct thermal_zone_of_device_ops lm75_of_thermal_ops = { |
181 | .get_temp = lm75_read_temp, | |
182 | }; | |
183 | ||
01a52397 DB |
184 | /*-----------------------------------------------------------------------*/ |
185 | ||
8ff69eeb | 186 | /* device probe and removal */ |
9ebd3d82 DB |
187 | |
188 | static int | |
189 | lm75_probe(struct i2c_client *client, const struct i2c_device_id *id) | |
190 | { | |
d663ec49 | 191 | struct device *dev = &client->dev; |
9ebd3d82 DB |
192 | struct lm75_data *data; |
193 | int status; | |
194 | u8 set_mask, clr_mask; | |
195 | int new; | |
0cd2c72d | 196 | enum lm75_type kind = id->driver_data; |
9ebd3d82 DB |
197 | |
198 | if (!i2c_check_functionality(client->adapter, | |
199 | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA)) | |
200 | return -EIO; | |
201 | ||
d663ec49 | 202 | data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL); |
9ebd3d82 DB |
203 | if (!data) |
204 | return -ENOMEM; | |
205 | ||
d663ec49 | 206 | data->client = client; |
9ebd3d82 | 207 | i2c_set_clientdata(client, data); |
9ebd3d82 DB |
208 | mutex_init(&data->update_lock); |
209 | ||
210 | /* Set to LM75 resolution (9 bits, 1/2 degree C) and range. | |
211 | * Then tweak to be more precise when appropriate. | |
212 | */ | |
213 | set_mask = 0; | |
8a5c5cc6 JD |
214 | clr_mask = LM75_SHUTDOWN; /* continuous conversions */ |
215 | ||
0cd2c72d | 216 | switch (kind) { |
8a5c5cc6 JD |
217 | case adt75: |
218 | clr_mask |= 1 << 5; /* not one-shot mode */ | |
0cd2c72d JD |
219 | data->resolution = 12; |
220 | data->sample_time = HZ / 8; | |
8a5c5cc6 JD |
221 | break; |
222 | case ds1775: | |
223 | case ds75: | |
224 | case stds75: | |
0cd2c72d JD |
225 | clr_mask |= 3 << 5; |
226 | set_mask |= 2 << 5; /* 11-bit mode */ | |
227 | data->resolution = 11; | |
228 | data->sample_time = HZ; | |
229 | break; | |
3fbc81e3 JD |
230 | case ds7505: |
231 | set_mask |= 3 << 5; /* 12-bit mode */ | |
232 | data->resolution = 12; | |
233 | data->sample_time = HZ / 4; | |
234 | break; | |
c98d6c65 | 235 | case g751: |
0cd2c72d JD |
236 | case lm75: |
237 | case lm75a: | |
238 | data->resolution = 9; | |
239 | data->sample_time = HZ / 2; | |
240 | break; | |
799fc602 MT |
241 | case lm75b: |
242 | data->resolution = 11; | |
243 | data->sample_time = HZ / 4; | |
244 | break; | |
0cd2c72d JD |
245 | case max6625: |
246 | data->resolution = 9; | |
247 | data->sample_time = HZ / 4; | |
248 | break; | |
249 | case max6626: | |
250 | data->resolution = 12; | |
251 | data->resolution_limits = 9; | |
252 | data->sample_time = HZ / 4; | |
253 | break; | |
254 | case tcn75: | |
255 | data->resolution = 9; | |
256 | data->sample_time = HZ / 8; | |
8a5c5cc6 JD |
257 | break; |
258 | case mcp980x: | |
0cd2c72d JD |
259 | data->resolution_limits = 9; |
260 | /* fall through */ | |
8a5c5cc6 JD |
261 | case tmp100: |
262 | case tmp101: | |
0cd2c72d JD |
263 | set_mask |= 3 << 5; /* 12-bit mode */ |
264 | data->resolution = 12; | |
265 | data->sample_time = HZ; | |
266 | clr_mask |= 1 << 7; /* not one-shot mode */ | |
267 | break; | |
c83959f8 FK |
268 | case tmp112: |
269 | set_mask |= 3 << 5; /* 12-bit mode */ | |
270 | clr_mask |= 1 << 7; /* not one-shot mode */ | |
271 | data->resolution = 12; | |
272 | data->sample_time = HZ / 4; | |
273 | break; | |
8a5c5cc6 JD |
274 | case tmp105: |
275 | case tmp175: | |
276 | case tmp275: | |
277 | case tmp75: | |
0cd2c72d | 278 | set_mask |= 3 << 5; /* 12-bit mode */ |
8a5c5cc6 | 279 | clr_mask |= 1 << 7; /* not one-shot mode */ |
0cd2c72d JD |
280 | data->resolution = 12; |
281 | data->sample_time = HZ / 2; | |
8a5c5cc6 JD |
282 | break; |
283 | } | |
9ebd3d82 DB |
284 | |
285 | /* configure as specified */ | |
286 | status = lm75_read_value(client, LM75_REG_CONF); | |
287 | if (status < 0) { | |
d663ec49 | 288 | dev_dbg(dev, "Can't read config? %d\n", status); |
13ac7a01 | 289 | return status; |
9ebd3d82 DB |
290 | } |
291 | data->orig_conf = status; | |
292 | new = status & ~clr_mask; | |
293 | new |= set_mask; | |
294 | if (status != new) | |
295 | lm75_write_value(client, LM75_REG_CONF, new); | |
d663ec49 | 296 | dev_dbg(dev, "Config %02x\n", new); |
9ebd3d82 | 297 | |
d663ec49 GR |
298 | data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name, |
299 | data, lm75_groups); | |
300 | if (IS_ERR(data->hwmon_dev)) | |
301 | return PTR_ERR(data->hwmon_dev); | |
9ebd3d82 | 302 | |
2251aef6 | 303 | data->tz = thermal_zone_of_sensor_register(data->hwmon_dev, 0, |
d663ec49 | 304 | data->hwmon_dev, |
2251aef6 | 305 | &lm75_of_thermal_ops); |
22e73183 EV |
306 | if (IS_ERR(data->tz)) |
307 | data->tz = NULL; | |
308 | ||
d663ec49 | 309 | dev_info(dev, "%s: sensor '%s'\n", |
739cf3a2 | 310 | dev_name(data->hwmon_dev), client->name); |
9ebd3d82 DB |
311 | |
312 | return 0; | |
9ebd3d82 DB |
313 | } |
314 | ||
315 | static int lm75_remove(struct i2c_client *client) | |
316 | { | |
317 | struct lm75_data *data = i2c_get_clientdata(client); | |
318 | ||
d663ec49 | 319 | thermal_zone_of_sensor_unregister(data->hwmon_dev, data->tz); |
9ebd3d82 | 320 | hwmon_device_unregister(data->hwmon_dev); |
9ebd3d82 | 321 | lm75_write_value(client, LM75_REG_CONF, data->orig_conf); |
9ebd3d82 DB |
322 | return 0; |
323 | } | |
324 | ||
325 | static const struct i2c_device_id lm75_ids[] = { | |
e96f9d89 | 326 | { "adt75", adt75, }, |
9ebd3d82 DB |
327 | { "ds1775", ds1775, }, |
328 | { "ds75", ds75, }, | |
3fbc81e3 | 329 | { "ds7505", ds7505, }, |
c98d6c65 | 330 | { "g751", g751, }, |
9ebd3d82 DB |
331 | { "lm75", lm75, }, |
332 | { "lm75a", lm75a, }, | |
799fc602 | 333 | { "lm75b", lm75b, }, |
9ebd3d82 DB |
334 | { "max6625", max6625, }, |
335 | { "max6626", max6626, }, | |
336 | { "mcp980x", mcp980x, }, | |
337 | { "stds75", stds75, }, | |
338 | { "tcn75", tcn75, }, | |
339 | { "tmp100", tmp100, }, | |
340 | { "tmp101", tmp101, }, | |
6d034059 | 341 | { "tmp105", tmp105, }, |
c83959f8 | 342 | { "tmp112", tmp112, }, |
9ebd3d82 DB |
343 | { "tmp175", tmp175, }, |
344 | { "tmp275", tmp275, }, | |
345 | { "tmp75", tmp75, }, | |
346 | { /* LIST END */ } | |
347 | }; | |
348 | MODULE_DEVICE_TABLE(i2c, lm75_ids); | |
349 | ||
05e82fe4 LS |
350 | #define LM75A_ID 0xA1 |
351 | ||
8ff69eeb | 352 | /* Return 0 if detection is successful, -ENODEV otherwise */ |
310ec792 | 353 | static int lm75_detect(struct i2c_client *new_client, |
8ff69eeb | 354 | struct i2c_board_info *info) |
1da177e4 | 355 | { |
8ff69eeb | 356 | struct i2c_adapter *adapter = new_client->adapter; |
1da177e4 | 357 | int i; |
e76f67b5 | 358 | int conf, hyst, os; |
05e82fe4 | 359 | bool is_lm75a = 0; |
1da177e4 | 360 | |
1da177e4 LT |
361 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | |
362 | I2C_FUNC_SMBUS_WORD_DATA)) | |
8ff69eeb | 363 | return -ENODEV; |
1da177e4 | 364 | |
426343ef JD |
365 | /* |
366 | * Now, we do the remaining detection. There is no identification- | |
367 | * dedicated register so we have to rely on several tricks: | |
368 | * unused bits, registers cycling over 8-address boundaries, | |
369 | * addresses 0x04-0x07 returning the last read value. | |
370 | * The cycling+unused addresses combination is not tested, | |
371 | * since it would significantly slow the detection down and would | |
372 | * hardly add any value. | |
373 | * | |
374 | * The National Semiconductor LM75A is different than earlier | |
375 | * LM75s. It has an ID byte of 0xaX (where X is the chip | |
376 | * revision, with 1 being the only revision in existence) in | |
377 | * register 7, and unused registers return 0xff rather than the | |
378 | * last read value. | |
379 | * | |
380 | * Note that this function only detects the original National | |
381 | * Semiconductor LM75 and the LM75A. Clones from other vendors | |
382 | * aren't detected, on purpose, because they are typically never | |
383 | * found on PC hardware. They are found on embedded designs where | |
384 | * they can be instantiated explicitly so detection is not needed. | |
385 | * The absence of identification registers on all these clones | |
386 | * would make their exhaustive detection very difficult and weak, | |
387 | * and odds are that the driver would bind to unsupported devices. | |
388 | */ | |
1da177e4 | 389 | |
e76f67b5 | 390 | /* Unused bits */ |
52df6440 | 391 | conf = i2c_smbus_read_byte_data(new_client, 1); |
e76f67b5 JD |
392 | if (conf & 0xe0) |
393 | return -ENODEV; | |
05e82fe4 LS |
394 | |
395 | /* First check for LM75A */ | |
396 | if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) { | |
397 | /* LM75A returns 0xff on unused registers so | |
398 | just to be sure we check for that too. */ | |
399 | if (i2c_smbus_read_byte_data(new_client, 4) != 0xff | |
400 | || i2c_smbus_read_byte_data(new_client, 5) != 0xff | |
401 | || i2c_smbus_read_byte_data(new_client, 6) != 0xff) | |
402 | return -ENODEV; | |
403 | is_lm75a = 1; | |
e76f67b5 JD |
404 | hyst = i2c_smbus_read_byte_data(new_client, 2); |
405 | os = i2c_smbus_read_byte_data(new_client, 3); | |
05e82fe4 LS |
406 | } else { /* Traditional style LM75 detection */ |
407 | /* Unused addresses */ | |
e76f67b5 JD |
408 | hyst = i2c_smbus_read_byte_data(new_client, 2); |
409 | if (i2c_smbus_read_byte_data(new_client, 4) != hyst | |
410 | || i2c_smbus_read_byte_data(new_client, 5) != hyst | |
411 | || i2c_smbus_read_byte_data(new_client, 6) != hyst | |
412 | || i2c_smbus_read_byte_data(new_client, 7) != hyst) | |
05e82fe4 | 413 | return -ENODEV; |
e76f67b5 JD |
414 | os = i2c_smbus_read_byte_data(new_client, 3); |
415 | if (i2c_smbus_read_byte_data(new_client, 4) != os | |
416 | || i2c_smbus_read_byte_data(new_client, 5) != os | |
417 | || i2c_smbus_read_byte_data(new_client, 6) != os | |
418 | || i2c_smbus_read_byte_data(new_client, 7) != os) | |
05e82fe4 LS |
419 | return -ENODEV; |
420 | } | |
4ad40cc5 GR |
421 | /* |
422 | * It is very unlikely that this is a LM75 if both | |
423 | * hysteresis and temperature limit registers are 0. | |
424 | */ | |
425 | if (hyst == 0 && os == 0) | |
426 | return -ENODEV; | |
1da177e4 | 427 | |
52df6440 | 428 | /* Addresses cycling */ |
e76f67b5 | 429 | for (i = 8; i <= 248; i += 40) { |
52df6440 | 430 | if (i2c_smbus_read_byte_data(new_client, i + 1) != conf |
e76f67b5 JD |
431 | || i2c_smbus_read_byte_data(new_client, i + 2) != hyst |
432 | || i2c_smbus_read_byte_data(new_client, i + 3) != os) | |
52df6440 | 433 | return -ENODEV; |
05e82fe4 LS |
434 | if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7) |
435 | != LM75A_ID) | |
436 | return -ENODEV; | |
1da177e4 LT |
437 | } |
438 | ||
05e82fe4 | 439 | strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE); |
c1685f61 | 440 | |
1da177e4 | 441 | return 0; |
01a52397 DB |
442 | } |
443 | ||
9914518e SD |
444 | #ifdef CONFIG_PM |
445 | static int lm75_suspend(struct device *dev) | |
446 | { | |
447 | int status; | |
448 | struct i2c_client *client = to_i2c_client(dev); | |
449 | status = lm75_read_value(client, LM75_REG_CONF); | |
450 | if (status < 0) { | |
451 | dev_dbg(&client->dev, "Can't read config? %d\n", status); | |
452 | return status; | |
453 | } | |
454 | status = status | LM75_SHUTDOWN; | |
455 | lm75_write_value(client, LM75_REG_CONF, status); | |
456 | return 0; | |
457 | } | |
458 | ||
459 | static int lm75_resume(struct device *dev) | |
460 | { | |
461 | int status; | |
462 | struct i2c_client *client = to_i2c_client(dev); | |
463 | status = lm75_read_value(client, LM75_REG_CONF); | |
464 | if (status < 0) { | |
465 | dev_dbg(&client->dev, "Can't read config? %d\n", status); | |
466 | return status; | |
467 | } | |
468 | status = status & ~LM75_SHUTDOWN; | |
469 | lm75_write_value(client, LM75_REG_CONF, status); | |
470 | return 0; | |
471 | } | |
472 | ||
473 | static const struct dev_pm_ops lm75_dev_pm_ops = { | |
474 | .suspend = lm75_suspend, | |
475 | .resume = lm75_resume, | |
476 | }; | |
477 | #define LM75_DEV_PM_OPS (&lm75_dev_pm_ops) | |
478 | #else | |
479 | #define LM75_DEV_PM_OPS NULL | |
480 | #endif /* CONFIG_PM */ | |
481 | ||
8ff69eeb JD |
482 | static struct i2c_driver lm75_driver = { |
483 | .class = I2C_CLASS_HWMON, | |
01a52397 | 484 | .driver = { |
8ff69eeb | 485 | .name = "lm75", |
9914518e | 486 | .pm = LM75_DEV_PM_OPS, |
01a52397 | 487 | }, |
8ff69eeb JD |
488 | .probe = lm75_probe, |
489 | .remove = lm75_remove, | |
490 | .id_table = lm75_ids, | |
491 | .detect = lm75_detect, | |
c3813d6a | 492 | .address_list = normal_i2c, |
01a52397 DB |
493 | }; |
494 | ||
495 | /*-----------------------------------------------------------------------*/ | |
496 | ||
497 | /* register access */ | |
498 | ||
caaa0f36 S |
499 | /* |
500 | * All registers are word-sized, except for the configuration register. | |
501 | * LM75 uses a high-byte first convention, which is exactly opposite to | |
502 | * the SMBus standard. | |
503 | */ | |
1da177e4 LT |
504 | static int lm75_read_value(struct i2c_client *client, u8 reg) |
505 | { | |
506 | if (reg == LM75_REG_CONF) | |
507 | return i2c_smbus_read_byte_data(client, reg); | |
90f4102c JD |
508 | else |
509 | return i2c_smbus_read_word_swapped(client, reg); | |
1da177e4 LT |
510 | } |
511 | ||
1da177e4 LT |
512 | static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value) |
513 | { | |
514 | if (reg == LM75_REG_CONF) | |
515 | return i2c_smbus_write_byte_data(client, reg, value); | |
516 | else | |
90f4102c | 517 | return i2c_smbus_write_word_swapped(client, reg, value); |
1da177e4 LT |
518 | } |
519 | ||
1da177e4 LT |
520 | static struct lm75_data *lm75_update_device(struct device *dev) |
521 | { | |
d663ec49 GR |
522 | struct lm75_data *data = dev_get_drvdata(dev); |
523 | struct i2c_client *client = data->client; | |
1f962f36 | 524 | struct lm75_data *ret = data; |
1da177e4 | 525 | |
9a61bf63 | 526 | mutex_lock(&data->update_lock); |
1da177e4 | 527 | |
87d0621a | 528 | if (time_after(jiffies, data->last_updated + data->sample_time) |
1da177e4 | 529 | || !data->valid) { |
9ca8e40c | 530 | int i; |
1da177e4 LT |
531 | dev_dbg(&client->dev, "Starting lm75 update\n"); |
532 | ||
bcccc3a2 DB |
533 | for (i = 0; i < ARRAY_SIZE(data->temp); i++) { |
534 | int status; | |
535 | ||
536 | status = lm75_read_value(client, LM75_REG_TEMP[i]); | |
1f962f36 FM |
537 | if (unlikely(status < 0)) { |
538 | dev_dbg(dev, | |
539 | "LM75: Failed to read value: reg %d, error %d\n", | |
540 | LM75_REG_TEMP[i], status); | |
541 | ret = ERR_PTR(status); | |
542 | data->valid = 0; | |
543 | goto abort; | |
544 | } | |
545 | data->temp[i] = status; | |
bcccc3a2 | 546 | } |
1da177e4 LT |
547 | data->last_updated = jiffies; |
548 | data->valid = 1; | |
549 | } | |
550 | ||
1f962f36 | 551 | abort: |
9a61bf63 | 552 | mutex_unlock(&data->update_lock); |
1f962f36 | 553 | return ret; |
1da177e4 LT |
554 | } |
555 | ||
f0967eea | 556 | module_i2c_driver(lm75_driver); |
1da177e4 LT |
557 | |
558 | MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>"); | |
559 | MODULE_DESCRIPTION("LM75 driver"); | |
560 | MODULE_LICENSE("GPL"); |