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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * lm75.c - Part of lm_sensors, Linux kernel modules for hardware
4 * monitoring
5 * Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl>
6 */
7
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/slab.h>
11#include <linux/jiffies.h>
12#include <linux/i2c.h>
13#include <linux/hwmon.h>
14#include <linux/hwmon-sysfs.h>
15#include <linux/err.h>
16#include <linux/of_device.h>
17#include <linux/of.h>
18#include <linux/regmap.h>
19#include <linux/util_macros.h>
20#include "lm75.h"
21
22/*
23 * This driver handles the LM75 and compatible digital temperature sensors.
24 */
25
26enum lm75_type { /* keep sorted in alphabetical order */
27 adt75,
28 ds1775,
29 ds75,
30 ds7505,
31 g751,
32 lm75,
33 lm75a,
34 lm75b,
35 max6625,
36 max6626,
37 max31725,
38 mcp980x,
39 pct2075,
40 stds75,
41 stlm75,
42 tcn75,
43 tmp100,
44 tmp101,
45 tmp105,
46 tmp112,
47 tmp175,
48 tmp275,
49 tmp75,
50 tmp75b,
51 tmp75c,
52};
53
54/**
55 * struct lm75_params - lm75 configuration parameters.
56 * @set_mask: Bits to set in configuration register when configuring
57 * the chip.
58 * @clr_mask: Bits to clear in configuration register when configuring
59 * the chip.
60 * @default_resolution: Default number of bits to represent the temperature
61 * value.
62 * @resolution_limits: Limit register resolution. Optional. Should be set if
63 * the resolution of limit registers does not match the
64 * resolution of the temperature register.
65 * @resolutions: List of resolutions associated with sample times.
66 * Optional. Should be set if num_sample_times is larger
67 * than 1, and if the resolution changes with sample times.
68 * If set, number of entries must match num_sample_times.
69 * @default_sample_time:Sample time to be set by default.
70 * @num_sample_times: Number of possible sample times to be set. Optional.
71 * Should be set if the number of sample times is larger
72 * than one.
73 * @sample_times: All the possible sample times to be set. Mandatory if
74 * num_sample_times is larger than 1. If set, number of
75 * entries must match num_sample_times.
76 */
77
78struct lm75_params {
79 u8 set_mask;
80 u8 clr_mask;
81 u8 default_resolution;
82 u8 resolution_limits;
83 const u8 *resolutions;
84 unsigned int default_sample_time;
85 u8 num_sample_times;
86 const unsigned int *sample_times;
87};
88
89/* Addresses scanned */
90static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
91 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
92
93/* The LM75 registers */
94#define LM75_REG_TEMP 0x00
95#define LM75_REG_CONF 0x01
96#define LM75_REG_HYST 0x02
97#define LM75_REG_MAX 0x03
98#define PCT2075_REG_IDLE 0x04
99
100/* Each client has this additional data */
101struct lm75_data {
102 struct i2c_client *client;
103 struct regmap *regmap;
104 u8 orig_conf;
105 u8 current_conf;
106 u8 resolution; /* In bits, 9 to 16 */
107 unsigned int sample_time; /* In ms */
108 enum lm75_type kind;
109 const struct lm75_params *params;
110};
111
112/*-----------------------------------------------------------------------*/
113
114static const u8 lm75_sample_set_masks[] = { 0 << 5, 1 << 5, 2 << 5, 3 << 5 };
115
116#define LM75_SAMPLE_CLEAR_MASK (3 << 5)
117
118/* The structure below stores the configuration values of the supported devices.
119 * In case of being supported multiple configurations, the default one must
120 * always be the first element of the array
121 */
122static const struct lm75_params device_params[] = {
123 [adt75] = {
124 .clr_mask = 1 << 5, /* not one-shot mode */
125 .default_resolution = 12,
126 .default_sample_time = MSEC_PER_SEC / 10,
127 },
128 [ds1775] = {
129 .clr_mask = 3 << 5,
130 .set_mask = 2 << 5, /* 11-bit mode */
131 .default_resolution = 11,
132 .default_sample_time = 500,
133 .num_sample_times = 4,
134 .sample_times = (unsigned int []){ 125, 250, 500, 1000 },
135 .resolutions = (u8 []) {9, 10, 11, 12 },
136 },
137 [ds75] = {
138 .clr_mask = 3 << 5,
139 .set_mask = 2 << 5, /* 11-bit mode */
140 .default_resolution = 11,
141 .default_sample_time = 600,
142 .num_sample_times = 4,
143 .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
144 .resolutions = (u8 []) {9, 10, 11, 12 },
145 },
146 [stds75] = {
147 .clr_mask = 3 << 5,
148 .set_mask = 2 << 5, /* 11-bit mode */
149 .default_resolution = 11,
150 .default_sample_time = 600,
151 .num_sample_times = 4,
152 .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
153 .resolutions = (u8 []) {9, 10, 11, 12 },
154 },
155 [stlm75] = {
156 .default_resolution = 9,
157 .default_sample_time = MSEC_PER_SEC / 6,
158 },
159 [ds7505] = {
160 .set_mask = 3 << 5, /* 12-bit mode*/
161 .default_resolution = 12,
162 .default_sample_time = 200,
163 .num_sample_times = 4,
164 .sample_times = (unsigned int []){ 25, 50, 100, 200 },
165 .resolutions = (u8 []) {9, 10, 11, 12 },
166 },
167 [g751] = {
168 .default_resolution = 9,
169 .default_sample_time = MSEC_PER_SEC / 10,
170 },
171 [lm75] = {
172 .default_resolution = 9,
173 .default_sample_time = MSEC_PER_SEC / 10,
174 },
175 [lm75a] = {
176 .default_resolution = 9,
177 .default_sample_time = MSEC_PER_SEC / 10,
178 },
179 [lm75b] = {
180 .default_resolution = 11,
181 .default_sample_time = MSEC_PER_SEC / 10,
182 },
183 [max6625] = {
184 .default_resolution = 9,
185 .default_sample_time = MSEC_PER_SEC / 7,
186 },
187 [max6626] = {
188 .default_resolution = 12,
189 .default_sample_time = MSEC_PER_SEC / 7,
190 .resolution_limits = 9,
191 },
192 [max31725] = {
193 .default_resolution = 16,
194 .default_sample_time = MSEC_PER_SEC / 20,
195 },
196 [tcn75] = {
197 .default_resolution = 9,
198 .default_sample_time = MSEC_PER_SEC / 18,
199 },
200 [pct2075] = {
201 .default_resolution = 11,
202 .default_sample_time = MSEC_PER_SEC / 10,
203 .num_sample_times = 31,
204 .sample_times = (unsigned int []){ 100, 200, 300, 400, 500, 600,
205 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700,
206 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700,
207 2800, 2900, 3000, 3100 },
208 },
209 [mcp980x] = {
210 .set_mask = 3 << 5, /* 12-bit mode */
211 .clr_mask = 1 << 7, /* not one-shot mode */
212 .default_resolution = 12,
213 .resolution_limits = 9,
214 .default_sample_time = 240,
215 .num_sample_times = 4,
216 .sample_times = (unsigned int []){ 30, 60, 120, 240 },
217 .resolutions = (u8 []) {9, 10, 11, 12 },
218 },
219 [tmp100] = {
220 .set_mask = 3 << 5, /* 12-bit mode */
221 .clr_mask = 1 << 7, /* not one-shot mode */
222 .default_resolution = 12,
223 .default_sample_time = 320,
224 .num_sample_times = 4,
225 .sample_times = (unsigned int []){ 40, 80, 160, 320 },
226 .resolutions = (u8 []) {9, 10, 11, 12 },
227 },
228 [tmp101] = {
229 .set_mask = 3 << 5, /* 12-bit mode */
230 .clr_mask = 1 << 7, /* not one-shot mode */
231 .default_resolution = 12,
232 .default_sample_time = 320,
233 .num_sample_times = 4,
234 .sample_times = (unsigned int []){ 40, 80, 160, 320 },
235 .resolutions = (u8 []) {9, 10, 11, 12 },
236 },
237 [tmp105] = {
238 .set_mask = 3 << 5, /* 12-bit mode */
239 .clr_mask = 1 << 7, /* not one-shot mode*/
240 .default_resolution = 12,
241 .default_sample_time = 220,
242 .num_sample_times = 4,
243 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
244 .resolutions = (u8 []) {9, 10, 11, 12 },
245 },
246 [tmp112] = {
247 .set_mask = 3 << 5, /* 8 samples / second */
248 .clr_mask = 1 << 7, /* no one-shot mode*/
249 .default_resolution = 12,
250 .default_sample_time = 125,
251 .num_sample_times = 4,
252 .sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
253 },
254 [tmp175] = {
255 .set_mask = 3 << 5, /* 12-bit mode */
256 .clr_mask = 1 << 7, /* not one-shot mode*/
257 .default_resolution = 12,
258 .default_sample_time = 220,
259 .num_sample_times = 4,
260 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
261 .resolutions = (u8 []) {9, 10, 11, 12 },
262 },
263 [tmp275] = {
264 .set_mask = 3 << 5, /* 12-bit mode */
265 .clr_mask = 1 << 7, /* not one-shot mode*/
266 .default_resolution = 12,
267 .default_sample_time = 220,
268 .num_sample_times = 4,
269 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
270 .resolutions = (u8 []) {9, 10, 11, 12 },
271 },
272 [tmp75] = {
273 .set_mask = 3 << 5, /* 12-bit mode */
274 .clr_mask = 1 << 7, /* not one-shot mode*/
275 .default_resolution = 12,
276 .default_sample_time = 220,
277 .num_sample_times = 4,
278 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
279 .resolutions = (u8 []) {9, 10, 11, 12 },
280 },
281 [tmp75b] = { /* not one-shot mode, Conversion rate 37Hz */
282 .clr_mask = 1 << 7 | 3 << 5,
283 .default_resolution = 12,
284 .default_sample_time = MSEC_PER_SEC / 37,
285 .sample_times = (unsigned int []){ MSEC_PER_SEC / 37,
286 MSEC_PER_SEC / 18,
287 MSEC_PER_SEC / 9, MSEC_PER_SEC / 4 },
288 .num_sample_times = 4,
289 },
290 [tmp75c] = {
291 .clr_mask = 1 << 5, /*not one-shot mode*/
292 .default_resolution = 12,
293 .default_sample_time = MSEC_PER_SEC / 12,
294 }
295};
296
297static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
298{
299 return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
300}
301
302static int lm75_write_config(struct lm75_data *data, u8 set_mask,
303 u8 clr_mask)
304{
305 u8 value;
306
307 clr_mask |= LM75_SHUTDOWN;
308 value = data->current_conf & ~clr_mask;
309 value |= set_mask;
310
311 if (data->current_conf != value) {
312 s32 err;
313
314 err = i2c_smbus_write_byte_data(data->client, LM75_REG_CONF,
315 value);
316 if (err)
317 return err;
318 data->current_conf = value;
319 }
320 return 0;
321}
322
323static int lm75_read(struct device *dev, enum hwmon_sensor_types type,
324 u32 attr, int channel, long *val)
325{
326 struct lm75_data *data = dev_get_drvdata(dev);
327 unsigned int regval;
328 int err, reg;
329
330 switch (type) {
331 case hwmon_chip:
332 switch (attr) {
333 case hwmon_chip_update_interval:
334 *val = data->sample_time;
335 break;
336 default:
337 return -EINVAL;
338 }
339 break;
340 case hwmon_temp:
341 switch (attr) {
342 case hwmon_temp_input:
343 reg = LM75_REG_TEMP;
344 break;
345 case hwmon_temp_max:
346 reg = LM75_REG_MAX;
347 break;
348 case hwmon_temp_max_hyst:
349 reg = LM75_REG_HYST;
350 break;
351 default:
352 return -EINVAL;
353 }
354 err = regmap_read(data->regmap, reg, ®val);
355 if (err < 0)
356 return err;
357
358 *val = lm75_reg_to_mc(regval, data->resolution);
359 break;
360 default:
361 return -EINVAL;
362 }
363 return 0;
364}
365
366static int lm75_write_temp(struct device *dev, u32 attr, long temp)
367{
368 struct lm75_data *data = dev_get_drvdata(dev);
369 u8 resolution;
370 int reg;
371
372 switch (attr) {
373 case hwmon_temp_max:
374 reg = LM75_REG_MAX;
375 break;
376 case hwmon_temp_max_hyst:
377 reg = LM75_REG_HYST;
378 break;
379 default:
380 return -EINVAL;
381 }
382
383 /*
384 * Resolution of limit registers is assumed to be the same as the
385 * temperature input register resolution unless given explicitly.
386 */
387 if (data->params->resolution_limits)
388 resolution = data->params->resolution_limits;
389 else
390 resolution = data->resolution;
391
392 temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
393 temp = DIV_ROUND_CLOSEST(temp << (resolution - 8),
394 1000) << (16 - resolution);
395
396 return regmap_write(data->regmap, reg, (u16)temp);
397}
398
399static int lm75_update_interval(struct device *dev, long val)
400{
401 struct lm75_data *data = dev_get_drvdata(dev);
402 unsigned int reg;
403 u8 index;
404 s32 err;
405
406 index = find_closest(val, data->params->sample_times,
407 (int)data->params->num_sample_times);
408
409 switch (data->kind) {
410 default:
411 err = lm75_write_config(data, lm75_sample_set_masks[index],
412 LM75_SAMPLE_CLEAR_MASK);
413 if (err)
414 return err;
415
416 data->sample_time = data->params->sample_times[index];
417 if (data->params->resolutions)
418 data->resolution = data->params->resolutions[index];
419 break;
420 case tmp112:
421 err = regmap_read(data->regmap, LM75_REG_CONF, ®);
422 if (err < 0)
423 return err;
424 reg &= ~0x00c0;
425 reg |= (3 - index) << 6;
426 err = regmap_write(data->regmap, LM75_REG_CONF, reg);
427 if (err < 0)
428 return err;
429 data->sample_time = data->params->sample_times[index];
430 break;
431 case pct2075:
432 err = i2c_smbus_write_byte_data(data->client, PCT2075_REG_IDLE,
433 index + 1);
434 if (err)
435 return err;
436 data->sample_time = data->params->sample_times[index];
437 break;
438 }
439 return 0;
440}
441
442static int lm75_write_chip(struct device *dev, u32 attr, long val)
443{
444 switch (attr) {
445 case hwmon_chip_update_interval:
446 return lm75_update_interval(dev, val);
447 default:
448 return -EINVAL;
449 }
450 return 0;
451}
452
453static int lm75_write(struct device *dev, enum hwmon_sensor_types type,
454 u32 attr, int channel, long val)
455{
456 switch (type) {
457 case hwmon_chip:
458 return lm75_write_chip(dev, attr, val);
459 case hwmon_temp:
460 return lm75_write_temp(dev, attr, val);
461 default:
462 return -EINVAL;
463 }
464 return 0;
465}
466
467static umode_t lm75_is_visible(const void *data, enum hwmon_sensor_types type,
468 u32 attr, int channel)
469{
470 const struct lm75_data *config_data = data;
471
472 switch (type) {
473 case hwmon_chip:
474 switch (attr) {
475 case hwmon_chip_update_interval:
476 if (config_data->params->num_sample_times > 1)
477 return 0644;
478 return 0444;
479 }
480 break;
481 case hwmon_temp:
482 switch (attr) {
483 case hwmon_temp_input:
484 return 0444;
485 case hwmon_temp_max:
486 case hwmon_temp_max_hyst:
487 return 0644;
488 }
489 break;
490 default:
491 break;
492 }
493 return 0;
494}
495
496static const struct hwmon_channel_info *lm75_info[] = {
497 HWMON_CHANNEL_INFO(chip,
498 HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL),
499 HWMON_CHANNEL_INFO(temp,
500 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST),
501 NULL
502};
503
504static const struct hwmon_ops lm75_hwmon_ops = {
505 .is_visible = lm75_is_visible,
506 .read = lm75_read,
507 .write = lm75_write,
508};
509
510static const struct hwmon_chip_info lm75_chip_info = {
511 .ops = &lm75_hwmon_ops,
512 .info = lm75_info,
513};
514
515static bool lm75_is_writeable_reg(struct device *dev, unsigned int reg)
516{
517 return reg != LM75_REG_TEMP;
518}
519
520static bool lm75_is_volatile_reg(struct device *dev, unsigned int reg)
521{
522 return reg == LM75_REG_TEMP || reg == LM75_REG_CONF;
523}
524
525static const struct regmap_config lm75_regmap_config = {
526 .reg_bits = 8,
527 .val_bits = 16,
528 .max_register = PCT2075_REG_IDLE,
529 .writeable_reg = lm75_is_writeable_reg,
530 .volatile_reg = lm75_is_volatile_reg,
531 .val_format_endian = REGMAP_ENDIAN_BIG,
532 .cache_type = REGCACHE_RBTREE,
533 .use_single_read = true,
534 .use_single_write = true,
535};
536
537static void lm75_remove(void *data)
538{
539 struct lm75_data *lm75 = data;
540 struct i2c_client *client = lm75->client;
541
542 i2c_smbus_write_byte_data(client, LM75_REG_CONF, lm75->orig_conf);
543}
544
545static int
546lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
547{
548 struct device *dev = &client->dev;
549 struct device *hwmon_dev;
550 struct lm75_data *data;
551 int status, err;
552 enum lm75_type kind;
553
554 if (client->dev.of_node)
555 kind = (enum lm75_type)of_device_get_match_data(&client->dev);
556 else
557 kind = id->driver_data;
558
559 if (!i2c_check_functionality(client->adapter,
560 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
561 return -EIO;
562
563 data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
564 if (!data)
565 return -ENOMEM;
566
567 data->client = client;
568 data->kind = kind;
569
570 data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
571 if (IS_ERR(data->regmap))
572 return PTR_ERR(data->regmap);
573
574 /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
575 * Then tweak to be more precise when appropriate.
576 */
577
578 data->params = &device_params[data->kind];
579
580 /* Save default sample time and resolution*/
581 data->sample_time = data->params->default_sample_time;
582 data->resolution = data->params->default_resolution;
583
584 /* Cache original configuration */
585 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
586 if (status < 0) {
587 dev_dbg(dev, "Can't read config? %d\n", status);
588 return status;
589 }
590 data->orig_conf = status;
591 data->current_conf = status;
592
593 err = lm75_write_config(data, data->params->set_mask,
594 data->params->clr_mask);
595 if (err)
596 return err;
597
598 err = devm_add_action_or_reset(dev, lm75_remove, data);
599 if (err)
600 return err;
601
602 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
603 data, &lm75_chip_info,
604 NULL);
605 if (IS_ERR(hwmon_dev))
606 return PTR_ERR(hwmon_dev);
607
608 dev_info(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), client->name);
609
610 return 0;
611}
612
613static const struct i2c_device_id lm75_ids[] = {
614 { "adt75", adt75, },
615 { "ds1775", ds1775, },
616 { "ds75", ds75, },
617 { "ds7505", ds7505, },
618 { "g751", g751, },
619 { "lm75", lm75, },
620 { "lm75a", lm75a, },
621 { "lm75b", lm75b, },
622 { "max6625", max6625, },
623 { "max6626", max6626, },
624 { "max31725", max31725, },
625 { "max31726", max31725, },
626 { "mcp980x", mcp980x, },
627 { "pct2075", pct2075, },
628 { "stds75", stds75, },
629 { "stlm75", stlm75, },
630 { "tcn75", tcn75, },
631 { "tmp100", tmp100, },
632 { "tmp101", tmp101, },
633 { "tmp105", tmp105, },
634 { "tmp112", tmp112, },
635 { "tmp175", tmp175, },
636 { "tmp275", tmp275, },
637 { "tmp75", tmp75, },
638 { "tmp75b", tmp75b, },
639 { "tmp75c", tmp75c, },
640 { /* LIST END */ }
641};
642MODULE_DEVICE_TABLE(i2c, lm75_ids);
643
644static const struct of_device_id __maybe_unused lm75_of_match[] = {
645 {
646 .compatible = "adi,adt75",
647 .data = (void *)adt75
648 },
649 {
650 .compatible = "dallas,ds1775",
651 .data = (void *)ds1775
652 },
653 {
654 .compatible = "dallas,ds75",
655 .data = (void *)ds75
656 },
657 {
658 .compatible = "dallas,ds7505",
659 .data = (void *)ds7505
660 },
661 {
662 .compatible = "gmt,g751",
663 .data = (void *)g751
664 },
665 {
666 .compatible = "national,lm75",
667 .data = (void *)lm75
668 },
669 {
670 .compatible = "national,lm75a",
671 .data = (void *)lm75a
672 },
673 {
674 .compatible = "national,lm75b",
675 .data = (void *)lm75b
676 },
677 {
678 .compatible = "maxim,max6625",
679 .data = (void *)max6625
680 },
681 {
682 .compatible = "maxim,max6626",
683 .data = (void *)max6626
684 },
685 {
686 .compatible = "maxim,max31725",
687 .data = (void *)max31725
688 },
689 {
690 .compatible = "maxim,max31726",
691 .data = (void *)max31725
692 },
693 {
694 .compatible = "maxim,mcp980x",
695 .data = (void *)mcp980x
696 },
697 {
698 .compatible = "nxp,pct2075",
699 .data = (void *)pct2075
700 },
701 {
702 .compatible = "st,stds75",
703 .data = (void *)stds75
704 },
705 {
706 .compatible = "st,stlm75",
707 .data = (void *)stlm75
708 },
709 {
710 .compatible = "microchip,tcn75",
711 .data = (void *)tcn75
712 },
713 {
714 .compatible = "ti,tmp100",
715 .data = (void *)tmp100
716 },
717 {
718 .compatible = "ti,tmp101",
719 .data = (void *)tmp101
720 },
721 {
722 .compatible = "ti,tmp105",
723 .data = (void *)tmp105
724 },
725 {
726 .compatible = "ti,tmp112",
727 .data = (void *)tmp112
728 },
729 {
730 .compatible = "ti,tmp175",
731 .data = (void *)tmp175
732 },
733 {
734 .compatible = "ti,tmp275",
735 .data = (void *)tmp275
736 },
737 {
738 .compatible = "ti,tmp75",
739 .data = (void *)tmp75
740 },
741 {
742 .compatible = "ti,tmp75b",
743 .data = (void *)tmp75b
744 },
745 {
746 .compatible = "ti,tmp75c",
747 .data = (void *)tmp75c
748 },
749 { },
750};
751MODULE_DEVICE_TABLE(of, lm75_of_match);
752
753#define LM75A_ID 0xA1
754
755/* Return 0 if detection is successful, -ENODEV otherwise */
756static int lm75_detect(struct i2c_client *new_client,
757 struct i2c_board_info *info)
758{
759 struct i2c_adapter *adapter = new_client->adapter;
760 int i;
761 int conf, hyst, os;
762 bool is_lm75a = 0;
763
764 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
765 I2C_FUNC_SMBUS_WORD_DATA))
766 return -ENODEV;
767
768 /*
769 * Now, we do the remaining detection. There is no identification-
770 * dedicated register so we have to rely on several tricks:
771 * unused bits, registers cycling over 8-address boundaries,
772 * addresses 0x04-0x07 returning the last read value.
773 * The cycling+unused addresses combination is not tested,
774 * since it would significantly slow the detection down and would
775 * hardly add any value.
776 *
777 * The National Semiconductor LM75A is different than earlier
778 * LM75s. It has an ID byte of 0xaX (where X is the chip
779 * revision, with 1 being the only revision in existence) in
780 * register 7, and unused registers return 0xff rather than the
781 * last read value.
782 *
783 * Note that this function only detects the original National
784 * Semiconductor LM75 and the LM75A. Clones from other vendors
785 * aren't detected, on purpose, because they are typically never
786 * found on PC hardware. They are found on embedded designs where
787 * they can be instantiated explicitly so detection is not needed.
788 * The absence of identification registers on all these clones
789 * would make their exhaustive detection very difficult and weak,
790 * and odds are that the driver would bind to unsupported devices.
791 */
792
793 /* Unused bits */
794 conf = i2c_smbus_read_byte_data(new_client, 1);
795 if (conf & 0xe0)
796 return -ENODEV;
797
798 /* First check for LM75A */
799 if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
800 /*
801 * LM75A returns 0xff on unused registers so
802 * just to be sure we check for that too.
803 */
804 if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
805 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
806 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
807 return -ENODEV;
808 is_lm75a = 1;
809 hyst = i2c_smbus_read_byte_data(new_client, 2);
810 os = i2c_smbus_read_byte_data(new_client, 3);
811 } else { /* Traditional style LM75 detection */
812 /* Unused addresses */
813 hyst = i2c_smbus_read_byte_data(new_client, 2);
814 if (i2c_smbus_read_byte_data(new_client, 4) != hyst
815 || i2c_smbus_read_byte_data(new_client, 5) != hyst
816 || i2c_smbus_read_byte_data(new_client, 6) != hyst
817 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
818 return -ENODEV;
819 os = i2c_smbus_read_byte_data(new_client, 3);
820 if (i2c_smbus_read_byte_data(new_client, 4) != os
821 || i2c_smbus_read_byte_data(new_client, 5) != os
822 || i2c_smbus_read_byte_data(new_client, 6) != os
823 || i2c_smbus_read_byte_data(new_client, 7) != os)
824 return -ENODEV;
825 }
826 /*
827 * It is very unlikely that this is a LM75 if both
828 * hysteresis and temperature limit registers are 0.
829 */
830 if (hyst == 0 && os == 0)
831 return -ENODEV;
832
833 /* Addresses cycling */
834 for (i = 8; i <= 248; i += 40) {
835 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
836 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
837 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
838 return -ENODEV;
839 if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
840 != LM75A_ID)
841 return -ENODEV;
842 }
843
844 strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
845
846 return 0;
847}
848
849#ifdef CONFIG_PM
850static int lm75_suspend(struct device *dev)
851{
852 int status;
853 struct i2c_client *client = to_i2c_client(dev);
854
855 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
856 if (status < 0) {
857 dev_dbg(&client->dev, "Can't read config? %d\n", status);
858 return status;
859 }
860 status = status | LM75_SHUTDOWN;
861 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
862 return 0;
863}
864
865static int lm75_resume(struct device *dev)
866{
867 int status;
868 struct i2c_client *client = to_i2c_client(dev);
869
870 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
871 if (status < 0) {
872 dev_dbg(&client->dev, "Can't read config? %d\n", status);
873 return status;
874 }
875 status = status & ~LM75_SHUTDOWN;
876 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
877 return 0;
878}
879
880static const struct dev_pm_ops lm75_dev_pm_ops = {
881 .suspend = lm75_suspend,
882 .resume = lm75_resume,
883};
884#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
885#else
886#define LM75_DEV_PM_OPS NULL
887#endif /* CONFIG_PM */
888
889static struct i2c_driver lm75_driver = {
890 .class = I2C_CLASS_HWMON,
891 .driver = {
892 .name = "lm75",
893 .of_match_table = of_match_ptr(lm75_of_match),
894 .pm = LM75_DEV_PM_OPS,
895 },
896 .probe = lm75_probe,
897 .id_table = lm75_ids,
898 .detect = lm75_detect,
899 .address_list = normal_i2c,
900};
901
902module_i2c_driver(lm75_driver);
903
904MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
905MODULE_DESCRIPTION("LM75 driver");
906MODULE_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/mutex.h>
30#include <linux/of.h>
31#include <linux/thermal.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_CONF 0x01
70static const u8 LM75_REG_TEMP[3] = {
71 0x00, /* input */
72 0x03, /* max */
73 0x02, /* hyst */
74};
75
76/* Each client has this additional data */
77struct lm75_data {
78 struct i2c_client *client;
79 struct device *hwmon_dev;
80 struct thermal_zone_device *tz;
81 struct mutex update_lock;
82 u8 orig_conf;
83 u8 resolution; /* In bits, between 9 and 12 */
84 u8 resolution_limits;
85 char valid; /* !=0 if registers are valid */
86 unsigned long last_updated; /* In jiffies */
87 unsigned long sample_time; /* In jiffies */
88 s16 temp[3]; /* Register values,
89 0 = input
90 1 = max
91 2 = hyst */
92};
93
94static int lm75_read_value(struct i2c_client *client, u8 reg);
95static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value);
96static struct lm75_data *lm75_update_device(struct device *dev);
97
98
99/*-----------------------------------------------------------------------*/
100
101static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
102{
103 return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
104}
105
106/* sysfs attributes for hwmon */
107
108static int lm75_read_temp(void *dev, int *temp)
109{
110 struct lm75_data *data = lm75_update_device(dev);
111
112 if (IS_ERR(data))
113 return PTR_ERR(data);
114
115 *temp = lm75_reg_to_mc(data->temp[0], data->resolution);
116
117 return 0;
118}
119
120static ssize_t show_temp(struct device *dev, struct device_attribute *da,
121 char *buf)
122{
123 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
124 struct lm75_data *data = lm75_update_device(dev);
125
126 if (IS_ERR(data))
127 return PTR_ERR(data);
128
129 return sprintf(buf, "%ld\n", lm75_reg_to_mc(data->temp[attr->index],
130 data->resolution));
131}
132
133static ssize_t set_temp(struct device *dev, struct device_attribute *da,
134 const char *buf, size_t count)
135{
136 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
137 struct lm75_data *data = dev_get_drvdata(dev);
138 struct i2c_client *client = data->client;
139 int nr = attr->index;
140 long temp;
141 int error;
142 u8 resolution;
143
144 error = kstrtol(buf, 10, &temp);
145 if (error)
146 return error;
147
148 /*
149 * Resolution of limit registers is assumed to be the same as the
150 * temperature input register resolution unless given explicitly.
151 */
152 if (attr->index && data->resolution_limits)
153 resolution = data->resolution_limits;
154 else
155 resolution = data->resolution;
156
157 mutex_lock(&data->update_lock);
158 temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
159 data->temp[nr] = DIV_ROUND_CLOSEST(temp << (resolution - 8),
160 1000) << (16 - resolution);
161 lm75_write_value(client, LM75_REG_TEMP[nr], data->temp[nr]);
162 mutex_unlock(&data->update_lock);
163 return count;
164}
165
166static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
167 show_temp, set_temp, 1);
168static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
169 show_temp, set_temp, 2);
170static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
171
172static struct attribute *lm75_attrs[] = {
173 &sensor_dev_attr_temp1_input.dev_attr.attr,
174 &sensor_dev_attr_temp1_max.dev_attr.attr,
175 &sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
176
177 NULL
178};
179ATTRIBUTE_GROUPS(lm75);
180
181static const struct thermal_zone_of_device_ops lm75_of_thermal_ops = {
182 .get_temp = lm75_read_temp,
183};
184
185/*-----------------------------------------------------------------------*/
186
187/* device probe and removal */
188
189static int
190lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
191{
192 struct device *dev = &client->dev;
193 struct lm75_data *data;
194 int status;
195 u8 set_mask, clr_mask;
196 int new;
197 enum lm75_type kind = id->driver_data;
198
199 if (!i2c_check_functionality(client->adapter,
200 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
201 return -EIO;
202
203 data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
204 if (!data)
205 return -ENOMEM;
206
207 data->client = client;
208 i2c_set_clientdata(client, data);
209 mutex_init(&data->update_lock);
210
211 /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
212 * Then tweak to be more precise when appropriate.
213 */
214 set_mask = 0;
215 clr_mask = LM75_SHUTDOWN; /* continuous conversions */
216
217 switch (kind) {
218 case adt75:
219 clr_mask |= 1 << 5; /* not one-shot mode */
220 data->resolution = 12;
221 data->sample_time = HZ / 8;
222 break;
223 case ds1775:
224 case ds75:
225 case stds75:
226 clr_mask |= 3 << 5;
227 set_mask |= 2 << 5; /* 11-bit mode */
228 data->resolution = 11;
229 data->sample_time = HZ;
230 break;
231 case ds7505:
232 set_mask |= 3 << 5; /* 12-bit mode */
233 data->resolution = 12;
234 data->sample_time = HZ / 4;
235 break;
236 case g751:
237 case lm75:
238 case lm75a:
239 data->resolution = 9;
240 data->sample_time = HZ / 2;
241 break;
242 case lm75b:
243 data->resolution = 11;
244 data->sample_time = HZ / 4;
245 break;
246 case max6625:
247 data->resolution = 9;
248 data->sample_time = HZ / 4;
249 break;
250 case max6626:
251 data->resolution = 12;
252 data->resolution_limits = 9;
253 data->sample_time = HZ / 4;
254 break;
255 case tcn75:
256 data->resolution = 9;
257 data->sample_time = HZ / 8;
258 break;
259 case mcp980x:
260 data->resolution_limits = 9;
261 /* fall through */
262 case tmp100:
263 case tmp101:
264 set_mask |= 3 << 5; /* 12-bit mode */
265 data->resolution = 12;
266 data->sample_time = HZ;
267 clr_mask |= 1 << 7; /* not one-shot mode */
268 break;
269 case tmp112:
270 set_mask |= 3 << 5; /* 12-bit mode */
271 clr_mask |= 1 << 7; /* not one-shot mode */
272 data->resolution = 12;
273 data->sample_time = HZ / 4;
274 break;
275 case tmp105:
276 case tmp175:
277 case tmp275:
278 case tmp75:
279 set_mask |= 3 << 5; /* 12-bit mode */
280 clr_mask |= 1 << 7; /* not one-shot mode */
281 data->resolution = 12;
282 data->sample_time = HZ / 2;
283 break;
284 case tmp75c:
285 clr_mask |= 1 << 5; /* not one-shot mode */
286 data->resolution = 12;
287 data->sample_time = HZ / 4;
288 break;
289 }
290
291 /* configure as specified */
292 status = lm75_read_value(client, LM75_REG_CONF);
293 if (status < 0) {
294 dev_dbg(dev, "Can't read config? %d\n", status);
295 return status;
296 }
297 data->orig_conf = status;
298 new = status & ~clr_mask;
299 new |= set_mask;
300 if (status != new)
301 lm75_write_value(client, LM75_REG_CONF, new);
302 dev_dbg(dev, "Config %02x\n", new);
303
304 data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
305 data, lm75_groups);
306 if (IS_ERR(data->hwmon_dev))
307 return PTR_ERR(data->hwmon_dev);
308
309 data->tz = thermal_zone_of_sensor_register(data->hwmon_dev, 0,
310 data->hwmon_dev,
311 &lm75_of_thermal_ops);
312 if (IS_ERR(data->tz))
313 data->tz = NULL;
314
315 dev_info(dev, "%s: sensor '%s'\n",
316 dev_name(data->hwmon_dev), client->name);
317
318 return 0;
319}
320
321static int lm75_remove(struct i2c_client *client)
322{
323 struct lm75_data *data = i2c_get_clientdata(client);
324
325 thermal_zone_of_sensor_unregister(data->hwmon_dev, data->tz);
326 hwmon_device_unregister(data->hwmon_dev);
327 lm75_write_value(client, LM75_REG_CONF, data->orig_conf);
328 return 0;
329}
330
331static const struct i2c_device_id lm75_ids[] = {
332 { "adt75", adt75, },
333 { "ds1775", ds1775, },
334 { "ds75", ds75, },
335 { "ds7505", ds7505, },
336 { "g751", g751, },
337 { "lm75", lm75, },
338 { "lm75a", lm75a, },
339 { "lm75b", lm75b, },
340 { "max6625", max6625, },
341 { "max6626", max6626, },
342 { "mcp980x", mcp980x, },
343 { "stds75", stds75, },
344 { "tcn75", tcn75, },
345 { "tmp100", tmp100, },
346 { "tmp101", tmp101, },
347 { "tmp105", tmp105, },
348 { "tmp112", tmp112, },
349 { "tmp175", tmp175, },
350 { "tmp275", tmp275, },
351 { "tmp75", tmp75, },
352 { "tmp75c", tmp75c, },
353 { /* LIST END */ }
354};
355MODULE_DEVICE_TABLE(i2c, lm75_ids);
356
357#define LM75A_ID 0xA1
358
359/* Return 0 if detection is successful, -ENODEV otherwise */
360static int lm75_detect(struct i2c_client *new_client,
361 struct i2c_board_info *info)
362{
363 struct i2c_adapter *adapter = new_client->adapter;
364 int i;
365 int conf, hyst, os;
366 bool is_lm75a = 0;
367
368 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
369 I2C_FUNC_SMBUS_WORD_DATA))
370 return -ENODEV;
371
372 /*
373 * Now, we do the remaining detection. There is no identification-
374 * dedicated register so we have to rely on several tricks:
375 * unused bits, registers cycling over 8-address boundaries,
376 * addresses 0x04-0x07 returning the last read value.
377 * The cycling+unused addresses combination is not tested,
378 * since it would significantly slow the detection down and would
379 * hardly add any value.
380 *
381 * The National Semiconductor LM75A is different than earlier
382 * LM75s. It has an ID byte of 0xaX (where X is the chip
383 * revision, with 1 being the only revision in existence) in
384 * register 7, and unused registers return 0xff rather than the
385 * last read value.
386 *
387 * Note that this function only detects the original National
388 * Semiconductor LM75 and the LM75A. Clones from other vendors
389 * aren't detected, on purpose, because they are typically never
390 * found on PC hardware. They are found on embedded designs where
391 * they can be instantiated explicitly so detection is not needed.
392 * The absence of identification registers on all these clones
393 * would make their exhaustive detection very difficult and weak,
394 * and odds are that the driver would bind to unsupported devices.
395 */
396
397 /* Unused bits */
398 conf = i2c_smbus_read_byte_data(new_client, 1);
399 if (conf & 0xe0)
400 return -ENODEV;
401
402 /* First check for LM75A */
403 if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
404 /* LM75A returns 0xff on unused registers so
405 just to be sure we check for that too. */
406 if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
407 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
408 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
409 return -ENODEV;
410 is_lm75a = 1;
411 hyst = i2c_smbus_read_byte_data(new_client, 2);
412 os = i2c_smbus_read_byte_data(new_client, 3);
413 } else { /* Traditional style LM75 detection */
414 /* Unused addresses */
415 hyst = i2c_smbus_read_byte_data(new_client, 2);
416 if (i2c_smbus_read_byte_data(new_client, 4) != hyst
417 || i2c_smbus_read_byte_data(new_client, 5) != hyst
418 || i2c_smbus_read_byte_data(new_client, 6) != hyst
419 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
420 return -ENODEV;
421 os = i2c_smbus_read_byte_data(new_client, 3);
422 if (i2c_smbus_read_byte_data(new_client, 4) != os
423 || i2c_smbus_read_byte_data(new_client, 5) != os
424 || i2c_smbus_read_byte_data(new_client, 6) != os
425 || i2c_smbus_read_byte_data(new_client, 7) != os)
426 return -ENODEV;
427 }
428 /*
429 * It is very unlikely that this is a LM75 if both
430 * hysteresis and temperature limit registers are 0.
431 */
432 if (hyst == 0 && os == 0)
433 return -ENODEV;
434
435 /* Addresses cycling */
436 for (i = 8; i <= 248; i += 40) {
437 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
438 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
439 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
440 return -ENODEV;
441 if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
442 != LM75A_ID)
443 return -ENODEV;
444 }
445
446 strlcpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
447
448 return 0;
449}
450
451#ifdef CONFIG_PM
452static int lm75_suspend(struct device *dev)
453{
454 int status;
455 struct i2c_client *client = to_i2c_client(dev);
456 status = lm75_read_value(client, LM75_REG_CONF);
457 if (status < 0) {
458 dev_dbg(&client->dev, "Can't read config? %d\n", status);
459 return status;
460 }
461 status = status | LM75_SHUTDOWN;
462 lm75_write_value(client, LM75_REG_CONF, status);
463 return 0;
464}
465
466static int lm75_resume(struct device *dev)
467{
468 int status;
469 struct i2c_client *client = to_i2c_client(dev);
470 status = lm75_read_value(client, LM75_REG_CONF);
471 if (status < 0) {
472 dev_dbg(&client->dev, "Can't read config? %d\n", status);
473 return status;
474 }
475 status = status & ~LM75_SHUTDOWN;
476 lm75_write_value(client, LM75_REG_CONF, status);
477 return 0;
478}
479
480static const struct dev_pm_ops lm75_dev_pm_ops = {
481 .suspend = lm75_suspend,
482 .resume = lm75_resume,
483};
484#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
485#else
486#define LM75_DEV_PM_OPS NULL
487#endif /* CONFIG_PM */
488
489static struct i2c_driver lm75_driver = {
490 .class = I2C_CLASS_HWMON,
491 .driver = {
492 .name = "lm75",
493 .pm = LM75_DEV_PM_OPS,
494 },
495 .probe = lm75_probe,
496 .remove = lm75_remove,
497 .id_table = lm75_ids,
498 .detect = lm75_detect,
499 .address_list = normal_i2c,
500};
501
502/*-----------------------------------------------------------------------*/
503
504/* register access */
505
506/*
507 * All registers are word-sized, except for the configuration register.
508 * LM75 uses a high-byte first convention, which is exactly opposite to
509 * the SMBus standard.
510 */
511static int lm75_read_value(struct i2c_client *client, u8 reg)
512{
513 if (reg == LM75_REG_CONF)
514 return i2c_smbus_read_byte_data(client, reg);
515 else
516 return i2c_smbus_read_word_swapped(client, reg);
517}
518
519static int lm75_write_value(struct i2c_client *client, u8 reg, u16 value)
520{
521 if (reg == LM75_REG_CONF)
522 return i2c_smbus_write_byte_data(client, reg, value);
523 else
524 return i2c_smbus_write_word_swapped(client, reg, value);
525}
526
527static struct lm75_data *lm75_update_device(struct device *dev)
528{
529 struct lm75_data *data = dev_get_drvdata(dev);
530 struct i2c_client *client = data->client;
531 struct lm75_data *ret = data;
532
533 mutex_lock(&data->update_lock);
534
535 if (time_after(jiffies, data->last_updated + data->sample_time)
536 || !data->valid) {
537 int i;
538 dev_dbg(&client->dev, "Starting lm75 update\n");
539
540 for (i = 0; i < ARRAY_SIZE(data->temp); i++) {
541 int status;
542
543 status = lm75_read_value(client, LM75_REG_TEMP[i]);
544 if (unlikely(status < 0)) {
545 dev_dbg(dev,
546 "LM75: Failed to read value: reg %d, error %d\n",
547 LM75_REG_TEMP[i], status);
548 ret = ERR_PTR(status);
549 data->valid = 0;
550 goto abort;
551 }
552 data->temp[i] = status;
553 }
554 data->last_updated = jiffies;
555 data->valid = 1;
556 }
557
558abort:
559 mutex_unlock(&data->update_lock);
560 return ret;
561}
562
563module_i2c_driver(lm75_driver);
564
565MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
566MODULE_DESCRIPTION("LM75 driver");
567MODULE_LICENSE("GPL");