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1/*
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 */
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.h>
27#include <linux/hwmon-sysfs.h>
28#include <linux/err.h>
29#include <linux/of.h>
30#include <linux/regmap.h>
31#include "lm75.h"
32
33
34/*
35 * This driver handles the LM75 and compatible digital temperature sensors.
36 */
37
38enum lm75_type { /* keep sorted in alphabetical order */
39 adt75,
40 ds1775,
41 ds75,
42 ds7505,
43 g751,
44 lm75,
45 lm75a,
46 lm75b,
47 max6625,
48 max6626,
49 mcp980x,
50 stds75,
51 tcn75,
52 tmp100,
53 tmp101,
54 tmp105,
55 tmp112,
56 tmp175,
57 tmp275,
58 tmp75,
59 tmp75c,
60};
61
62/* Addresses scanned */
63static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
64 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
65
66
67/* The LM75 registers */
68#define LM75_REG_TEMP 0x00
69#define LM75_REG_CONF 0x01
70#define LM75_REG_HYST 0x02
71#define LM75_REG_MAX 0x03
72
73/* Each client has this additional data */
74struct lm75_data {
75 struct i2c_client *client;
76 struct regmap *regmap;
77 u8 orig_conf;
78 u8 resolution; /* In bits, between 9 and 12 */
79 u8 resolution_limits;
80 unsigned int sample_time; /* In ms */
81};
82
83/*-----------------------------------------------------------------------*/
84
85static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
86{
87 return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
88}
89
90static int lm75_read(struct device *dev, enum hwmon_sensor_types type,
91 u32 attr, int channel, long *val)
92{
93 struct lm75_data *data = dev_get_drvdata(dev);
94 unsigned int regval;
95 int err, reg;
96
97 switch (type) {
98 case hwmon_chip:
99 switch (attr) {
100 case hwmon_chip_update_interval:
101 *val = data->sample_time;
102 break;;
103 default:
104 return -EINVAL;
105 }
106 break;
107 case hwmon_temp:
108 switch (attr) {
109 case hwmon_temp_input:
110 reg = LM75_REG_TEMP;
111 break;
112 case hwmon_temp_max:
113 reg = LM75_REG_MAX;
114 break;
115 case hwmon_temp_max_hyst:
116 reg = LM75_REG_HYST;
117 break;
118 default:
119 return -EINVAL;
120 }
121 err = regmap_read(data->regmap, reg, ®val);
122 if (err < 0)
123 return err;
124
125 *val = lm75_reg_to_mc(regval, data->resolution);
126 break;
127 default:
128 return -EINVAL;
129 }
130 return 0;
131}
132
133static int lm75_write(struct device *dev, enum hwmon_sensor_types type,
134 u32 attr, int channel, long temp)
135{
136 struct lm75_data *data = dev_get_drvdata(dev);
137 u8 resolution;
138 int reg;
139
140 if (type != hwmon_temp)
141 return -EINVAL;
142
143 switch (attr) {
144 case hwmon_temp_max:
145 reg = LM75_REG_MAX;
146 break;
147 case hwmon_temp_max_hyst:
148 reg = LM75_REG_HYST;
149 break;
150 default:
151 return -EINVAL;
152 }
153
154 /*
155 * Resolution of limit registers is assumed to be the same as the
156 * temperature input register resolution unless given explicitly.
157 */
158 if (data->resolution_limits)
159 resolution = data->resolution_limits;
160 else
161 resolution = data->resolution;
162
163 temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
164 temp = DIV_ROUND_CLOSEST(temp << (resolution - 8),
165 1000) << (16 - resolution);
166
167 return regmap_write(data->regmap, reg, temp);
168}
169
170static umode_t lm75_is_visible(const void *data, enum hwmon_sensor_types type,
171 u32 attr, int channel)
172{
173 switch (type) {
174 case hwmon_chip:
175 switch (attr) {
176 case hwmon_chip_update_interval:
177 return S_IRUGO;
178 }
179 break;
180 case hwmon_temp:
181 switch (attr) {
182 case hwmon_temp_input:
183 return S_IRUGO;
184 case hwmon_temp_max:
185 case hwmon_temp_max_hyst:
186 return S_IRUGO | S_IWUSR;
187 }
188 break;
189 default:
190 break;
191 }
192 return 0;
193}
194
195/*-----------------------------------------------------------------------*/
196
197/* device probe and removal */
198
199/* chip configuration */
200
201static const u32 lm75_chip_config[] = {
202 HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL,
203 0
204};
205
206static const struct hwmon_channel_info lm75_chip = {
207 .type = hwmon_chip,
208 .config = lm75_chip_config,
209};
210
211static const u32 lm75_temp_config[] = {
212 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST,
213 0
214};
215
216static const struct hwmon_channel_info lm75_temp = {
217 .type = hwmon_temp,
218 .config = lm75_temp_config,
219};
220
221static const struct hwmon_channel_info *lm75_info[] = {
222 &lm75_chip,
223 &lm75_temp,
224 NULL
225};
226
227static const struct hwmon_ops lm75_hwmon_ops = {
228 .is_visible = lm75_is_visible,
229 .read = lm75_read,
230 .write = lm75_write,
231};
232
233static const struct hwmon_chip_info lm75_chip_info = {
234 .ops = &lm75_hwmon_ops,
235 .info = lm75_info,
236};
237
238static bool lm75_is_writeable_reg(struct device *dev, unsigned int reg)
239{
240 return reg != LM75_REG_TEMP;
241}
242
243static bool lm75_is_volatile_reg(struct device *dev, unsigned int reg)
244{
245 return reg == LM75_REG_TEMP;
246}
247
248static const struct regmap_config lm75_regmap_config = {
249 .reg_bits = 8,
250 .val_bits = 16,
251 .max_register = LM75_REG_MAX,
252 .writeable_reg = lm75_is_writeable_reg,
253 .volatile_reg = lm75_is_volatile_reg,
254 .val_format_endian = REGMAP_ENDIAN_BIG,
255 .cache_type = REGCACHE_RBTREE,
256 .use_single_rw = true,
257};
258
259static void lm75_remove(void *data)
260{
261 struct lm75_data *lm75 = data;
262 struct i2c_client *client = lm75->client;
263
264 i2c_smbus_write_byte_data(client, LM75_REG_CONF, lm75->orig_conf);
265}
266
267static int
268lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
269{
270 struct device *dev = &client->dev;
271 struct device *hwmon_dev;
272 struct lm75_data *data;
273 int status, err;
274 u8 set_mask, clr_mask;
275 int new;
276 enum lm75_type kind = id->driver_data;
277
278 if (!i2c_check_functionality(client->adapter,
279 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
280 return -EIO;
281
282 data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
283 if (!data)
284 return -ENOMEM;
285
286 data->client = client;
287
288 data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
289 if (IS_ERR(data->regmap))
290 return PTR_ERR(data->regmap);
291
292 /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
293 * Then tweak to be more precise when appropriate.
294 */
295 set_mask = 0;
296 clr_mask = LM75_SHUTDOWN; /* continuous conversions */
297
298 switch (kind) {
299 case adt75:
300 clr_mask |= 1 << 5; /* not one-shot mode */
301 data->resolution = 12;
302 data->sample_time = MSEC_PER_SEC / 8;
303 break;
304 case ds1775:
305 case ds75:
306 case stds75:
307 clr_mask |= 3 << 5;
308 set_mask |= 2 << 5; /* 11-bit mode */
309 data->resolution = 11;
310 data->sample_time = MSEC_PER_SEC;
311 break;
312 case ds7505:
313 set_mask |= 3 << 5; /* 12-bit mode */
314 data->resolution = 12;
315 data->sample_time = MSEC_PER_SEC / 4;
316 break;
317 case g751:
318 case lm75:
319 case lm75a:
320 data->resolution = 9;
321 data->sample_time = MSEC_PER_SEC / 2;
322 break;
323 case lm75b:
324 data->resolution = 11;
325 data->sample_time = MSEC_PER_SEC / 4;
326 break;
327 case max6625:
328 data->resolution = 9;
329 data->sample_time = MSEC_PER_SEC / 4;
330 break;
331 case max6626:
332 data->resolution = 12;
333 data->resolution_limits = 9;
334 data->sample_time = MSEC_PER_SEC / 4;
335 break;
336 case tcn75:
337 data->resolution = 9;
338 data->sample_time = MSEC_PER_SEC / 8;
339 break;
340 case mcp980x:
341 data->resolution_limits = 9;
342 /* fall through */
343 case tmp100:
344 case tmp101:
345 set_mask |= 3 << 5; /* 12-bit mode */
346 data->resolution = 12;
347 data->sample_time = MSEC_PER_SEC;
348 clr_mask |= 1 << 7; /* not one-shot mode */
349 break;
350 case tmp112:
351 set_mask |= 3 << 5; /* 12-bit mode */
352 clr_mask |= 1 << 7; /* not one-shot mode */
353 data->resolution = 12;
354 data->sample_time = MSEC_PER_SEC / 4;
355 break;
356 case tmp105:
357 case tmp175:
358 case tmp275:
359 case tmp75:
360 set_mask |= 3 << 5; /* 12-bit mode */
361 clr_mask |= 1 << 7; /* not one-shot mode */
362 data->resolution = 12;
363 data->sample_time = MSEC_PER_SEC / 2;
364 break;
365 case tmp75c:
366 clr_mask |= 1 << 5; /* not one-shot mode */
367 data->resolution = 12;
368 data->sample_time = MSEC_PER_SEC / 4;
369 break;
370 }
371
372 /* configure as specified */
373 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
374 if (status < 0) {
375 dev_dbg(dev, "Can't read config? %d\n", status);
376 return status;
377 }
378 data->orig_conf = status;
379 new = status & ~clr_mask;
380 new |= set_mask;
381 if (status != new)
382 i2c_smbus_write_byte_data(client, LM75_REG_CONF, new);
383
384 err = devm_add_action_or_reset(dev, lm75_remove, data);
385 if (err)
386 return err;
387
388 dev_dbg(dev, "Config %02x\n", new);
389
390 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
391 data, &lm75_chip_info,
392 NULL);
393 if (IS_ERR(hwmon_dev))
394 return PTR_ERR(hwmon_dev);
395
396 dev_info(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), client->name);
397
398 return 0;
399}
400
401static const struct i2c_device_id lm75_ids[] = {
402 { "adt75", adt75, },
403 { "ds1775", ds1775, },
404 { "ds75", ds75, },
405 { "ds7505", ds7505, },
406 { "g751", g751, },
407 { "lm75", lm75, },
408 { "lm75a", lm75a, },
409 { "lm75b", lm75b, },
410 { "max6625", max6625, },
411 { "max6626", max6626, },
412 { "mcp980x", mcp980x, },
413 { "stds75", stds75, },
414 { "tcn75", tcn75, },
415 { "tmp100", tmp100, },
416 { "tmp101", tmp101, },
417 { "tmp105", tmp105, },
418 { "tmp112", tmp112, },
419 { "tmp175", tmp175, },
420 { "tmp275", tmp275, },
421 { "tmp75", tmp75, },
422 { "tmp75c", tmp75c, },
423 { /* LIST END */ }
424};
425MODULE_DEVICE_TABLE(i2c, lm75_ids);
426
427#define LM75A_ID 0xA1
428
429/* Return 0 if detection is successful, -ENODEV otherwise */
430static int lm75_detect(struct i2c_client *new_client,
431 struct i2c_board_info *info)
432{
433 struct i2c_adapter *adapter = new_client->adapter;
434 int i;
435 int conf, hyst, os;
436 bool is_lm75a = 0;
437
438 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
439 I2C_FUNC_SMBUS_WORD_DATA))
440 return -ENODEV;
441
442 /*
443 * Now, we do the remaining detection. There is no identification-
444 * dedicated register so we have to rely on several tricks:
445 * unused bits, registers cycling over 8-address boundaries,
446 * addresses 0x04-0x07 returning the last read value.
447 * The cycling+unused addresses combination is not tested,
448 * since it would significantly slow the detection down and would
449 * hardly add any value.
450 *
451 * The National Semiconductor LM75A is different than earlier
452 * LM75s. It has an ID byte of 0xaX (where X is the chip
453 * revision, with 1 being the only revision in existence) in
454 * register 7, and unused registers return 0xff rather than the
455 * last read value.
456 *
457 * Note that this function only detects the original National
458 * Semiconductor LM75 and the LM75A. Clones from other vendors
459 * aren't detected, on purpose, because they are typically never
460 * found on PC hardware. They are found on embedded designs where
461 * they can be instantiated explicitly so detection is not needed.
462 * The absence of identification registers on all these clones
463 * would make their exhaustive detection very difficult and weak,
464 * and odds are that the driver would bind to unsupported devices.
465 */
466
467 /* Unused bits */
468 conf = i2c_smbus_read_byte_data(new_client, 1);
469 if (conf & 0xe0)
470 return -ENODEV;
471
472 /* First check for LM75A */
473 if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
474 /* LM75A returns 0xff on unused registers so
475 just to be sure we check for that too. */
476 if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
477 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
478 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
479 return -ENODEV;
480 is_lm75a = 1;
481 hyst = i2c_smbus_read_byte_data(new_client, 2);
482 os = i2c_smbus_read_byte_data(new_client, 3);
483 } else { /* Traditional style LM75 detection */
484 /* Unused addresses */
485 hyst = i2c_smbus_read_byte_data(new_client, 2);
486 if (i2c_smbus_read_byte_data(new_client, 4) != hyst
487 || i2c_smbus_read_byte_data(new_client, 5) != hyst
488 || i2c_smbus_read_byte_data(new_client, 6) != hyst
489 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
490 return -ENODEV;
491 os = i2c_smbus_read_byte_data(new_client, 3);
492 if (i2c_smbus_read_byte_data(new_client, 4) != os
493 || i2c_smbus_read_byte_data(new_client, 5) != os
494 || i2c_smbus_read_byte_data(new_client, 6) != os
495 || i2c_smbus_read_byte_data(new_client, 7) != os)
496 return -ENODEV;
497 }
498 /*
499 * It is very unlikely that this is a LM75 if both
500 * hysteresis and temperature limit registers are 0.
501 */
502 if (hyst == 0 && os == 0)
503 return -ENODEV;
504
505 /* Addresses cycling */
506 for (i = 8; i <= 248; i += 40) {
507 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
508 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
509 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
510 return -ENODEV;
511 if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
512 != LM75A_ID)
513 return -ENODEV;
514 }
515
516 strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
517
518 return 0;
519}
520
521#ifdef CONFIG_PM
522static int lm75_suspend(struct device *dev)
523{
524 int status;
525 struct i2c_client *client = to_i2c_client(dev);
526 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
527 if (status < 0) {
528 dev_dbg(&client->dev, "Can't read config? %d\n", status);
529 return status;
530 }
531 status = status | LM75_SHUTDOWN;
532 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
533 return 0;
534}
535
536static int lm75_resume(struct device *dev)
537{
538 int status;
539 struct i2c_client *client = to_i2c_client(dev);
540 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
541 if (status < 0) {
542 dev_dbg(&client->dev, "Can't read config? %d\n", status);
543 return status;
544 }
545 status = status & ~LM75_SHUTDOWN;
546 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
547 return 0;
548}
549
550static const struct dev_pm_ops lm75_dev_pm_ops = {
551 .suspend = lm75_suspend,
552 .resume = lm75_resume,
553};
554#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
555#else
556#define LM75_DEV_PM_OPS NULL
557#endif /* CONFIG_PM */
558
559static struct i2c_driver lm75_driver = {
560 .class = I2C_CLASS_HWMON,
561 .driver = {
562 .name = "lm75",
563 .pm = LM75_DEV_PM_OPS,
564 },
565 .probe = lm75_probe,
566 .id_table = lm75_ids,
567 .detect = lm75_detect,
568 .address_list = normal_i2c,
569};
570
571module_i2c_driver(lm75_driver);
572
573MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
574MODULE_DESCRIPTION("LM75 driver");
575MODULE_LICENSE("GPL");
1/*
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 */
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.h>
27#include <linux/hwmon-sysfs.h>
28#include <linux/err.h>
29#include <linux/of_device.h>
30#include <linux/of.h>
31#include <linux/regmap.h>
32#include "lm75.h"
33
34
35/*
36 * This driver handles the LM75 and compatible digital temperature sensors.
37 */
38
39enum lm75_type { /* keep sorted in alphabetical order */
40 adt75,
41 ds1775,
42 ds75,
43 ds7505,
44 g751,
45 lm75,
46 lm75a,
47 lm75b,
48 max6625,
49 max6626,
50 mcp980x,
51 stds75,
52 tcn75,
53 tmp100,
54 tmp101,
55 tmp105,
56 tmp112,
57 tmp175,
58 tmp275,
59 tmp75,
60 tmp75c,
61};
62
63/* Addresses scanned */
64static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
65 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
66
67
68/* The LM75 registers */
69#define LM75_REG_TEMP 0x00
70#define LM75_REG_CONF 0x01
71#define LM75_REG_HYST 0x02
72#define LM75_REG_MAX 0x03
73
74/* Each client has this additional data */
75struct lm75_data {
76 struct i2c_client *client;
77 struct regmap *regmap;
78 u8 orig_conf;
79 u8 resolution; /* In bits, between 9 and 12 */
80 u8 resolution_limits;
81 unsigned int sample_time; /* In ms */
82};
83
84/*-----------------------------------------------------------------------*/
85
86static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
87{
88 return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
89}
90
91static int lm75_read(struct device *dev, enum hwmon_sensor_types type,
92 u32 attr, int channel, long *val)
93{
94 struct lm75_data *data = dev_get_drvdata(dev);
95 unsigned int regval;
96 int err, reg;
97
98 switch (type) {
99 case hwmon_chip:
100 switch (attr) {
101 case hwmon_chip_update_interval:
102 *val = data->sample_time;
103 break;
104 default:
105 return -EINVAL;
106 }
107 break;
108 case hwmon_temp:
109 switch (attr) {
110 case hwmon_temp_input:
111 reg = LM75_REG_TEMP;
112 break;
113 case hwmon_temp_max:
114 reg = LM75_REG_MAX;
115 break;
116 case hwmon_temp_max_hyst:
117 reg = LM75_REG_HYST;
118 break;
119 default:
120 return -EINVAL;
121 }
122 err = regmap_read(data->regmap, reg, ®val);
123 if (err < 0)
124 return err;
125
126 *val = lm75_reg_to_mc(regval, data->resolution);
127 break;
128 default:
129 return -EINVAL;
130 }
131 return 0;
132}
133
134static int lm75_write(struct device *dev, enum hwmon_sensor_types type,
135 u32 attr, int channel, long temp)
136{
137 struct lm75_data *data = dev_get_drvdata(dev);
138 u8 resolution;
139 int reg;
140
141 if (type != hwmon_temp)
142 return -EINVAL;
143
144 switch (attr) {
145 case hwmon_temp_max:
146 reg = LM75_REG_MAX;
147 break;
148 case hwmon_temp_max_hyst:
149 reg = LM75_REG_HYST;
150 break;
151 default:
152 return -EINVAL;
153 }
154
155 /*
156 * Resolution of limit registers is assumed to be the same as the
157 * temperature input register resolution unless given explicitly.
158 */
159 if (data->resolution_limits)
160 resolution = data->resolution_limits;
161 else
162 resolution = data->resolution;
163
164 temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
165 temp = DIV_ROUND_CLOSEST(temp << (resolution - 8),
166 1000) << (16 - resolution);
167
168 return regmap_write(data->regmap, reg, temp);
169}
170
171static umode_t lm75_is_visible(const void *data, enum hwmon_sensor_types type,
172 u32 attr, int channel)
173{
174 switch (type) {
175 case hwmon_chip:
176 switch (attr) {
177 case hwmon_chip_update_interval:
178 return S_IRUGO;
179 }
180 break;
181 case hwmon_temp:
182 switch (attr) {
183 case hwmon_temp_input:
184 return S_IRUGO;
185 case hwmon_temp_max:
186 case hwmon_temp_max_hyst:
187 return S_IRUGO | S_IWUSR;
188 }
189 break;
190 default:
191 break;
192 }
193 return 0;
194}
195
196/*-----------------------------------------------------------------------*/
197
198/* device probe and removal */
199
200/* chip configuration */
201
202static const u32 lm75_chip_config[] = {
203 HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL,
204 0
205};
206
207static const struct hwmon_channel_info lm75_chip = {
208 .type = hwmon_chip,
209 .config = lm75_chip_config,
210};
211
212static const u32 lm75_temp_config[] = {
213 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST,
214 0
215};
216
217static const struct hwmon_channel_info lm75_temp = {
218 .type = hwmon_temp,
219 .config = lm75_temp_config,
220};
221
222static const struct hwmon_channel_info *lm75_info[] = {
223 &lm75_chip,
224 &lm75_temp,
225 NULL
226};
227
228static const struct hwmon_ops lm75_hwmon_ops = {
229 .is_visible = lm75_is_visible,
230 .read = lm75_read,
231 .write = lm75_write,
232};
233
234static const struct hwmon_chip_info lm75_chip_info = {
235 .ops = &lm75_hwmon_ops,
236 .info = lm75_info,
237};
238
239static bool lm75_is_writeable_reg(struct device *dev, unsigned int reg)
240{
241 return reg != LM75_REG_TEMP;
242}
243
244static bool lm75_is_volatile_reg(struct device *dev, unsigned int reg)
245{
246 return reg == LM75_REG_TEMP;
247}
248
249static const struct regmap_config lm75_regmap_config = {
250 .reg_bits = 8,
251 .val_bits = 16,
252 .max_register = LM75_REG_MAX,
253 .writeable_reg = lm75_is_writeable_reg,
254 .volatile_reg = lm75_is_volatile_reg,
255 .val_format_endian = REGMAP_ENDIAN_BIG,
256 .cache_type = REGCACHE_RBTREE,
257 .use_single_rw = true,
258};
259
260static void lm75_remove(void *data)
261{
262 struct lm75_data *lm75 = data;
263 struct i2c_client *client = lm75->client;
264
265 i2c_smbus_write_byte_data(client, LM75_REG_CONF, lm75->orig_conf);
266}
267
268static int
269lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
270{
271 struct device *dev = &client->dev;
272 struct device *hwmon_dev;
273 struct lm75_data *data;
274 int status, err;
275 u8 set_mask, clr_mask;
276 int new;
277 enum lm75_type kind;
278
279 if (client->dev.of_node)
280 kind = (enum lm75_type)of_device_get_match_data(&client->dev);
281 else
282 kind = id->driver_data;
283
284 if (!i2c_check_functionality(client->adapter,
285 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
286 return -EIO;
287
288 data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
289 if (!data)
290 return -ENOMEM;
291
292 data->client = client;
293
294 data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
295 if (IS_ERR(data->regmap))
296 return PTR_ERR(data->regmap);
297
298 /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
299 * Then tweak to be more precise when appropriate.
300 */
301 set_mask = 0;
302 clr_mask = LM75_SHUTDOWN; /* continuous conversions */
303
304 switch (kind) {
305 case adt75:
306 clr_mask |= 1 << 5; /* not one-shot mode */
307 data->resolution = 12;
308 data->sample_time = MSEC_PER_SEC / 8;
309 break;
310 case ds1775:
311 case ds75:
312 case stds75:
313 clr_mask |= 3 << 5;
314 set_mask |= 2 << 5; /* 11-bit mode */
315 data->resolution = 11;
316 data->sample_time = MSEC_PER_SEC;
317 break;
318 case ds7505:
319 set_mask |= 3 << 5; /* 12-bit mode */
320 data->resolution = 12;
321 data->sample_time = MSEC_PER_SEC / 4;
322 break;
323 case g751:
324 case lm75:
325 case lm75a:
326 data->resolution = 9;
327 data->sample_time = MSEC_PER_SEC / 2;
328 break;
329 case lm75b:
330 data->resolution = 11;
331 data->sample_time = MSEC_PER_SEC / 4;
332 break;
333 case max6625:
334 data->resolution = 9;
335 data->sample_time = MSEC_PER_SEC / 4;
336 break;
337 case max6626:
338 data->resolution = 12;
339 data->resolution_limits = 9;
340 data->sample_time = MSEC_PER_SEC / 4;
341 break;
342 case tcn75:
343 data->resolution = 9;
344 data->sample_time = MSEC_PER_SEC / 8;
345 break;
346 case mcp980x:
347 data->resolution_limits = 9;
348 /* fall through */
349 case tmp100:
350 case tmp101:
351 set_mask |= 3 << 5; /* 12-bit mode */
352 data->resolution = 12;
353 data->sample_time = MSEC_PER_SEC;
354 clr_mask |= 1 << 7; /* not one-shot mode */
355 break;
356 case tmp112:
357 set_mask |= 3 << 5; /* 12-bit mode */
358 clr_mask |= 1 << 7; /* not one-shot mode */
359 data->resolution = 12;
360 data->sample_time = MSEC_PER_SEC / 4;
361 break;
362 case tmp105:
363 case tmp175:
364 case tmp275:
365 case tmp75:
366 set_mask |= 3 << 5; /* 12-bit mode */
367 clr_mask |= 1 << 7; /* not one-shot mode */
368 data->resolution = 12;
369 data->sample_time = MSEC_PER_SEC / 2;
370 break;
371 case tmp75c:
372 clr_mask |= 1 << 5; /* not one-shot mode */
373 data->resolution = 12;
374 data->sample_time = MSEC_PER_SEC / 4;
375 break;
376 }
377
378 /* configure as specified */
379 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
380 if (status < 0) {
381 dev_dbg(dev, "Can't read config? %d\n", status);
382 return status;
383 }
384 data->orig_conf = status;
385 new = status & ~clr_mask;
386 new |= set_mask;
387 if (status != new)
388 i2c_smbus_write_byte_data(client, LM75_REG_CONF, new);
389
390 err = devm_add_action_or_reset(dev, lm75_remove, data);
391 if (err)
392 return err;
393
394 dev_dbg(dev, "Config %02x\n", new);
395
396 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
397 data, &lm75_chip_info,
398 NULL);
399 if (IS_ERR(hwmon_dev))
400 return PTR_ERR(hwmon_dev);
401
402 dev_info(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), client->name);
403
404 return 0;
405}
406
407static const struct i2c_device_id lm75_ids[] = {
408 { "adt75", adt75, },
409 { "ds1775", ds1775, },
410 { "ds75", ds75, },
411 { "ds7505", ds7505, },
412 { "g751", g751, },
413 { "lm75", lm75, },
414 { "lm75a", lm75a, },
415 { "lm75b", lm75b, },
416 { "max6625", max6625, },
417 { "max6626", max6626, },
418 { "mcp980x", mcp980x, },
419 { "stds75", stds75, },
420 { "tcn75", tcn75, },
421 { "tmp100", tmp100, },
422 { "tmp101", tmp101, },
423 { "tmp105", tmp105, },
424 { "tmp112", tmp112, },
425 { "tmp175", tmp175, },
426 { "tmp275", tmp275, },
427 { "tmp75", tmp75, },
428 { "tmp75c", tmp75c, },
429 { /* LIST END */ }
430};
431MODULE_DEVICE_TABLE(i2c, lm75_ids);
432
433static const struct of_device_id lm75_of_match[] = {
434 {
435 .compatible = "adi,adt75",
436 .data = (void *)adt75
437 },
438 {
439 .compatible = "dallas,ds1775",
440 .data = (void *)ds1775
441 },
442 {
443 .compatible = "dallas,ds75",
444 .data = (void *)ds75
445 },
446 {
447 .compatible = "dallas,ds7505",
448 .data = (void *)ds7505
449 },
450 {
451 .compatible = "gmt,g751",
452 .data = (void *)g751
453 },
454 {
455 .compatible = "national,lm75",
456 .data = (void *)lm75
457 },
458 {
459 .compatible = "national,lm75a",
460 .data = (void *)lm75a
461 },
462 {
463 .compatible = "national,lm75b",
464 .data = (void *)lm75b
465 },
466 {
467 .compatible = "maxim,max6625",
468 .data = (void *)max6625
469 },
470 {
471 .compatible = "maxim,max6626",
472 .data = (void *)max6626
473 },
474 {
475 .compatible = "maxim,mcp980x",
476 .data = (void *)mcp980x
477 },
478 {
479 .compatible = "st,stds75",
480 .data = (void *)stds75
481 },
482 {
483 .compatible = "microchip,tcn75",
484 .data = (void *)tcn75
485 },
486 {
487 .compatible = "ti,tmp100",
488 .data = (void *)tmp100
489 },
490 {
491 .compatible = "ti,tmp101",
492 .data = (void *)tmp101
493 },
494 {
495 .compatible = "ti,tmp105",
496 .data = (void *)tmp105
497 },
498 {
499 .compatible = "ti,tmp112",
500 .data = (void *)tmp112
501 },
502 {
503 .compatible = "ti,tmp175",
504 .data = (void *)tmp175
505 },
506 {
507 .compatible = "ti,tmp275",
508 .data = (void *)tmp275
509 },
510 {
511 .compatible = "ti,tmp75",
512 .data = (void *)tmp75
513 },
514 {
515 .compatible = "ti,tmp75c",
516 .data = (void *)tmp75c
517 },
518 { },
519};
520MODULE_DEVICE_TABLE(of, lm75_of_match);
521
522#define LM75A_ID 0xA1
523
524/* Return 0 if detection is successful, -ENODEV otherwise */
525static int lm75_detect(struct i2c_client *new_client,
526 struct i2c_board_info *info)
527{
528 struct i2c_adapter *adapter = new_client->adapter;
529 int i;
530 int conf, hyst, os;
531 bool is_lm75a = 0;
532
533 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
534 I2C_FUNC_SMBUS_WORD_DATA))
535 return -ENODEV;
536
537 /*
538 * Now, we do the remaining detection. There is no identification-
539 * dedicated register so we have to rely on several tricks:
540 * unused bits, registers cycling over 8-address boundaries,
541 * addresses 0x04-0x07 returning the last read value.
542 * The cycling+unused addresses combination is not tested,
543 * since it would significantly slow the detection down and would
544 * hardly add any value.
545 *
546 * The National Semiconductor LM75A is different than earlier
547 * LM75s. It has an ID byte of 0xaX (where X is the chip
548 * revision, with 1 being the only revision in existence) in
549 * register 7, and unused registers return 0xff rather than the
550 * last read value.
551 *
552 * Note that this function only detects the original National
553 * Semiconductor LM75 and the LM75A. Clones from other vendors
554 * aren't detected, on purpose, because they are typically never
555 * found on PC hardware. They are found on embedded designs where
556 * they can be instantiated explicitly so detection is not needed.
557 * The absence of identification registers on all these clones
558 * would make their exhaustive detection very difficult and weak,
559 * and odds are that the driver would bind to unsupported devices.
560 */
561
562 /* Unused bits */
563 conf = i2c_smbus_read_byte_data(new_client, 1);
564 if (conf & 0xe0)
565 return -ENODEV;
566
567 /* First check for LM75A */
568 if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
569 /* LM75A returns 0xff on unused registers so
570 just to be sure we check for that too. */
571 if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
572 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
573 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
574 return -ENODEV;
575 is_lm75a = 1;
576 hyst = i2c_smbus_read_byte_data(new_client, 2);
577 os = i2c_smbus_read_byte_data(new_client, 3);
578 } else { /* Traditional style LM75 detection */
579 /* Unused addresses */
580 hyst = i2c_smbus_read_byte_data(new_client, 2);
581 if (i2c_smbus_read_byte_data(new_client, 4) != hyst
582 || i2c_smbus_read_byte_data(new_client, 5) != hyst
583 || i2c_smbus_read_byte_data(new_client, 6) != hyst
584 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
585 return -ENODEV;
586 os = i2c_smbus_read_byte_data(new_client, 3);
587 if (i2c_smbus_read_byte_data(new_client, 4) != os
588 || i2c_smbus_read_byte_data(new_client, 5) != os
589 || i2c_smbus_read_byte_data(new_client, 6) != os
590 || i2c_smbus_read_byte_data(new_client, 7) != os)
591 return -ENODEV;
592 }
593 /*
594 * It is very unlikely that this is a LM75 if both
595 * hysteresis and temperature limit registers are 0.
596 */
597 if (hyst == 0 && os == 0)
598 return -ENODEV;
599
600 /* Addresses cycling */
601 for (i = 8; i <= 248; i += 40) {
602 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
603 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
604 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
605 return -ENODEV;
606 if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
607 != LM75A_ID)
608 return -ENODEV;
609 }
610
611 strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
612
613 return 0;
614}
615
616#ifdef CONFIG_PM
617static int lm75_suspend(struct device *dev)
618{
619 int status;
620 struct i2c_client *client = to_i2c_client(dev);
621 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
622 if (status < 0) {
623 dev_dbg(&client->dev, "Can't read config? %d\n", status);
624 return status;
625 }
626 status = status | LM75_SHUTDOWN;
627 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
628 return 0;
629}
630
631static int lm75_resume(struct device *dev)
632{
633 int status;
634 struct i2c_client *client = to_i2c_client(dev);
635 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
636 if (status < 0) {
637 dev_dbg(&client->dev, "Can't read config? %d\n", status);
638 return status;
639 }
640 status = status & ~LM75_SHUTDOWN;
641 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
642 return 0;
643}
644
645static const struct dev_pm_ops lm75_dev_pm_ops = {
646 .suspend = lm75_suspend,
647 .resume = lm75_resume,
648};
649#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
650#else
651#define LM75_DEV_PM_OPS NULL
652#endif /* CONFIG_PM */
653
654static struct i2c_driver lm75_driver = {
655 .class = I2C_CLASS_HWMON,
656 .driver = {
657 .name = "lm75",
658 .of_match_table = of_match_ptr(lm75_of_match),
659 .pm = LM75_DEV_PM_OPS,
660 },
661 .probe = lm75_probe,
662 .id_table = lm75_ids,
663 .detect = lm75_detect,
664 .address_list = normal_i2c,
665};
666
667module_i2c_driver(lm75_driver);
668
669MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
670MODULE_DESCRIPTION("LM75 driver");
671MODULE_LICENSE("GPL");