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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// 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 <linux/regulator/consumer.h>
21#include "lm75.h"
22
23/*
24 * This driver handles the LM75 and compatible digital temperature sensors.
25 */
26
27enum lm75_type { /* keep sorted in alphabetical order */
28 adt75,
29 at30ts74,
30 ds1775,
31 ds75,
32 ds7505,
33 g751,
34 lm75,
35 lm75a,
36 lm75b,
37 max6625,
38 max6626,
39 max31725,
40 mcp980x,
41 pct2075,
42 stds75,
43 stlm75,
44 tcn75,
45 tmp100,
46 tmp101,
47 tmp105,
48 tmp112,
49 tmp175,
50 tmp275,
51 tmp75,
52 tmp75b,
53 tmp75c,
54 tmp1075,
55};
56
57/**
58 * struct lm75_params - lm75 configuration parameters.
59 * @set_mask: Bits to set in configuration register when configuring
60 * the chip.
61 * @clr_mask: Bits to clear in configuration register when configuring
62 * the chip.
63 * @default_resolution: Default number of bits to represent the temperature
64 * value.
65 * @resolution_limits: Limit register resolution. Optional. Should be set if
66 * the resolution of limit registers does not match the
67 * resolution of the temperature register.
68 * @resolutions: List of resolutions associated with sample times.
69 * Optional. Should be set if num_sample_times is larger
70 * than 1, and if the resolution changes with sample times.
71 * If set, number of entries must match num_sample_times.
72 * @default_sample_time:Sample time to be set by default.
73 * @num_sample_times: Number of possible sample times to be set. Optional.
74 * Should be set if the number of sample times is larger
75 * than one.
76 * @sample_times: All the possible sample times to be set. Mandatory if
77 * num_sample_times is larger than 1. If set, number of
78 * entries must match num_sample_times.
79 */
80
81struct lm75_params {
82 u8 set_mask;
83 u8 clr_mask;
84 u8 default_resolution;
85 u8 resolution_limits;
86 const u8 *resolutions;
87 unsigned int default_sample_time;
88 u8 num_sample_times;
89 const unsigned int *sample_times;
90};
91
92/* Addresses scanned */
93static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
94 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
95
96/* The LM75 registers */
97#define LM75_REG_TEMP 0x00
98#define LM75_REG_CONF 0x01
99#define LM75_REG_HYST 0x02
100#define LM75_REG_MAX 0x03
101#define PCT2075_REG_IDLE 0x04
102
103/* Each client has this additional data */
104struct lm75_data {
105 struct i2c_client *client;
106 struct regmap *regmap;
107 struct regulator *vs;
108 u8 orig_conf;
109 u8 current_conf;
110 u8 resolution; /* In bits, 9 to 16 */
111 unsigned int sample_time; /* In ms */
112 enum lm75_type kind;
113 const struct lm75_params *params;
114};
115
116/*-----------------------------------------------------------------------*/
117
118static const u8 lm75_sample_set_masks[] = { 0 << 5, 1 << 5, 2 << 5, 3 << 5 };
119
120#define LM75_SAMPLE_CLEAR_MASK (3 << 5)
121
122/* The structure below stores the configuration values of the supported devices.
123 * In case of being supported multiple configurations, the default one must
124 * always be the first element of the array
125 */
126static const struct lm75_params device_params[] = {
127 [adt75] = {
128 .clr_mask = 1 << 5, /* not one-shot mode */
129 .default_resolution = 12,
130 .default_sample_time = MSEC_PER_SEC / 10,
131 },
132 [at30ts74] = {
133 .set_mask = 3 << 5, /* 12-bit mode*/
134 .default_resolution = 12,
135 .default_sample_time = 200,
136 .num_sample_times = 4,
137 .sample_times = (unsigned int []){ 25, 50, 100, 200 },
138 .resolutions = (u8 []) {9, 10, 11, 12 },
139 },
140 [ds1775] = {
141 .clr_mask = 3 << 5,
142 .set_mask = 2 << 5, /* 11-bit mode */
143 .default_resolution = 11,
144 .default_sample_time = 500,
145 .num_sample_times = 4,
146 .sample_times = (unsigned int []){ 125, 250, 500, 1000 },
147 .resolutions = (u8 []) {9, 10, 11, 12 },
148 },
149 [ds75] = {
150 .clr_mask = 3 << 5,
151 .set_mask = 2 << 5, /* 11-bit mode */
152 .default_resolution = 11,
153 .default_sample_time = 600,
154 .num_sample_times = 4,
155 .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
156 .resolutions = (u8 []) {9, 10, 11, 12 },
157 },
158 [stds75] = {
159 .clr_mask = 3 << 5,
160 .set_mask = 2 << 5, /* 11-bit mode */
161 .default_resolution = 11,
162 .default_sample_time = 600,
163 .num_sample_times = 4,
164 .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
165 .resolutions = (u8 []) {9, 10, 11, 12 },
166 },
167 [stlm75] = {
168 .default_resolution = 9,
169 .default_sample_time = MSEC_PER_SEC / 6,
170 },
171 [ds7505] = {
172 .set_mask = 3 << 5, /* 12-bit mode*/
173 .default_resolution = 12,
174 .default_sample_time = 200,
175 .num_sample_times = 4,
176 .sample_times = (unsigned int []){ 25, 50, 100, 200 },
177 .resolutions = (u8 []) {9, 10, 11, 12 },
178 },
179 [g751] = {
180 .default_resolution = 9,
181 .default_sample_time = MSEC_PER_SEC / 10,
182 },
183 [lm75] = {
184 .default_resolution = 9,
185 .default_sample_time = MSEC_PER_SEC / 10,
186 },
187 [lm75a] = {
188 .default_resolution = 9,
189 .default_sample_time = MSEC_PER_SEC / 10,
190 },
191 [lm75b] = {
192 .default_resolution = 11,
193 .default_sample_time = MSEC_PER_SEC / 10,
194 },
195 [max6625] = {
196 .default_resolution = 9,
197 .default_sample_time = MSEC_PER_SEC / 7,
198 },
199 [max6626] = {
200 .default_resolution = 12,
201 .default_sample_time = MSEC_PER_SEC / 7,
202 .resolution_limits = 9,
203 },
204 [max31725] = {
205 .default_resolution = 16,
206 .default_sample_time = MSEC_PER_SEC / 20,
207 },
208 [tcn75] = {
209 .default_resolution = 9,
210 .default_sample_time = MSEC_PER_SEC / 18,
211 },
212 [pct2075] = {
213 .default_resolution = 11,
214 .default_sample_time = MSEC_PER_SEC / 10,
215 .num_sample_times = 31,
216 .sample_times = (unsigned int []){ 100, 200, 300, 400, 500, 600,
217 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700,
218 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700,
219 2800, 2900, 3000, 3100 },
220 },
221 [mcp980x] = {
222 .set_mask = 3 << 5, /* 12-bit mode */
223 .clr_mask = 1 << 7, /* not one-shot mode */
224 .default_resolution = 12,
225 .resolution_limits = 9,
226 .default_sample_time = 240,
227 .num_sample_times = 4,
228 .sample_times = (unsigned int []){ 30, 60, 120, 240 },
229 .resolutions = (u8 []) {9, 10, 11, 12 },
230 },
231 [tmp100] = {
232 .set_mask = 3 << 5, /* 12-bit mode */
233 .clr_mask = 1 << 7, /* not one-shot mode */
234 .default_resolution = 12,
235 .default_sample_time = 320,
236 .num_sample_times = 4,
237 .sample_times = (unsigned int []){ 40, 80, 160, 320 },
238 .resolutions = (u8 []) {9, 10, 11, 12 },
239 },
240 [tmp101] = {
241 .set_mask = 3 << 5, /* 12-bit mode */
242 .clr_mask = 1 << 7, /* not one-shot mode */
243 .default_resolution = 12,
244 .default_sample_time = 320,
245 .num_sample_times = 4,
246 .sample_times = (unsigned int []){ 40, 80, 160, 320 },
247 .resolutions = (u8 []) {9, 10, 11, 12 },
248 },
249 [tmp105] = {
250 .set_mask = 3 << 5, /* 12-bit mode */
251 .clr_mask = 1 << 7, /* not one-shot mode*/
252 .default_resolution = 12,
253 .default_sample_time = 220,
254 .num_sample_times = 4,
255 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
256 .resolutions = (u8 []) {9, 10, 11, 12 },
257 },
258 [tmp112] = {
259 .set_mask = 3 << 5, /* 8 samples / second */
260 .clr_mask = 1 << 7, /* no one-shot mode*/
261 .default_resolution = 12,
262 .default_sample_time = 125,
263 .num_sample_times = 4,
264 .sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
265 },
266 [tmp175] = {
267 .set_mask = 3 << 5, /* 12-bit mode */
268 .clr_mask = 1 << 7, /* not one-shot mode*/
269 .default_resolution = 12,
270 .default_sample_time = 220,
271 .num_sample_times = 4,
272 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
273 .resolutions = (u8 []) {9, 10, 11, 12 },
274 },
275 [tmp275] = {
276 .set_mask = 3 << 5, /* 12-bit mode */
277 .clr_mask = 1 << 7, /* not one-shot mode*/
278 .default_resolution = 12,
279 .default_sample_time = 220,
280 .num_sample_times = 4,
281 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
282 .resolutions = (u8 []) {9, 10, 11, 12 },
283 },
284 [tmp75] = {
285 .set_mask = 3 << 5, /* 12-bit mode */
286 .clr_mask = 1 << 7, /* not one-shot mode*/
287 .default_resolution = 12,
288 .default_sample_time = 220,
289 .num_sample_times = 4,
290 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
291 .resolutions = (u8 []) {9, 10, 11, 12 },
292 },
293 [tmp75b] = { /* not one-shot mode, Conversion rate 37Hz */
294 .clr_mask = 1 << 7 | 3 << 5,
295 .default_resolution = 12,
296 .default_sample_time = MSEC_PER_SEC / 37,
297 .sample_times = (unsigned int []){ MSEC_PER_SEC / 37,
298 MSEC_PER_SEC / 18,
299 MSEC_PER_SEC / 9, MSEC_PER_SEC / 4 },
300 .num_sample_times = 4,
301 },
302 [tmp75c] = {
303 .clr_mask = 1 << 5, /*not one-shot mode*/
304 .default_resolution = 12,
305 .default_sample_time = MSEC_PER_SEC / 12,
306 },
307 [tmp1075] = { /* not one-shot mode, 27.5 ms sample rate */
308 .clr_mask = 1 << 5 | 1 << 6 | 1 << 7,
309 .default_resolution = 12,
310 .default_sample_time = 28,
311 .num_sample_times = 4,
312 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
313 }
314};
315
316static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
317{
318 return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
319}
320
321static int lm75_write_config(struct lm75_data *data, u8 set_mask,
322 u8 clr_mask)
323{
324 u8 value;
325
326 clr_mask |= LM75_SHUTDOWN;
327 value = data->current_conf & ~clr_mask;
328 value |= set_mask;
329
330 if (data->current_conf != value) {
331 s32 err;
332
333 err = i2c_smbus_write_byte_data(data->client, LM75_REG_CONF,
334 value);
335 if (err)
336 return err;
337 data->current_conf = value;
338 }
339 return 0;
340}
341
342static int lm75_read(struct device *dev, enum hwmon_sensor_types type,
343 u32 attr, int channel, long *val)
344{
345 struct lm75_data *data = dev_get_drvdata(dev);
346 unsigned int regval;
347 int err, reg;
348
349 switch (type) {
350 case hwmon_chip:
351 switch (attr) {
352 case hwmon_chip_update_interval:
353 *val = data->sample_time;
354 break;
355 default:
356 return -EINVAL;
357 }
358 break;
359 case hwmon_temp:
360 switch (attr) {
361 case hwmon_temp_input:
362 reg = LM75_REG_TEMP;
363 break;
364 case hwmon_temp_max:
365 reg = LM75_REG_MAX;
366 break;
367 case hwmon_temp_max_hyst:
368 reg = LM75_REG_HYST;
369 break;
370 default:
371 return -EINVAL;
372 }
373 err = regmap_read(data->regmap, reg, ®val);
374 if (err < 0)
375 return err;
376
377 *val = lm75_reg_to_mc(regval, data->resolution);
378 break;
379 default:
380 return -EINVAL;
381 }
382 return 0;
383}
384
385static int lm75_write_temp(struct device *dev, u32 attr, long temp)
386{
387 struct lm75_data *data = dev_get_drvdata(dev);
388 u8 resolution;
389 int reg;
390
391 switch (attr) {
392 case hwmon_temp_max:
393 reg = LM75_REG_MAX;
394 break;
395 case hwmon_temp_max_hyst:
396 reg = LM75_REG_HYST;
397 break;
398 default:
399 return -EINVAL;
400 }
401
402 /*
403 * Resolution of limit registers is assumed to be the same as the
404 * temperature input register resolution unless given explicitly.
405 */
406 if (data->params->resolution_limits)
407 resolution = data->params->resolution_limits;
408 else
409 resolution = data->resolution;
410
411 temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
412 temp = DIV_ROUND_CLOSEST(temp << (resolution - 8),
413 1000) << (16 - resolution);
414
415 return regmap_write(data->regmap, reg, (u16)temp);
416}
417
418static int lm75_update_interval(struct device *dev, long val)
419{
420 struct lm75_data *data = dev_get_drvdata(dev);
421 unsigned int reg;
422 u8 index;
423 s32 err;
424
425 index = find_closest(val, data->params->sample_times,
426 (int)data->params->num_sample_times);
427
428 switch (data->kind) {
429 default:
430 err = lm75_write_config(data, lm75_sample_set_masks[index],
431 LM75_SAMPLE_CLEAR_MASK);
432 if (err)
433 return err;
434
435 data->sample_time = data->params->sample_times[index];
436 if (data->params->resolutions)
437 data->resolution = data->params->resolutions[index];
438 break;
439 case tmp112:
440 err = regmap_read(data->regmap, LM75_REG_CONF, ®);
441 if (err < 0)
442 return err;
443 reg &= ~0x00c0;
444 reg |= (3 - index) << 6;
445 err = regmap_write(data->regmap, LM75_REG_CONF, reg);
446 if (err < 0)
447 return err;
448 data->sample_time = data->params->sample_times[index];
449 break;
450 case pct2075:
451 err = i2c_smbus_write_byte_data(data->client, PCT2075_REG_IDLE,
452 index + 1);
453 if (err)
454 return err;
455 data->sample_time = data->params->sample_times[index];
456 break;
457 }
458 return 0;
459}
460
461static int lm75_write_chip(struct device *dev, u32 attr, long val)
462{
463 switch (attr) {
464 case hwmon_chip_update_interval:
465 return lm75_update_interval(dev, val);
466 default:
467 return -EINVAL;
468 }
469 return 0;
470}
471
472static int lm75_write(struct device *dev, enum hwmon_sensor_types type,
473 u32 attr, int channel, long val)
474{
475 switch (type) {
476 case hwmon_chip:
477 return lm75_write_chip(dev, attr, val);
478 case hwmon_temp:
479 return lm75_write_temp(dev, attr, val);
480 default:
481 return -EINVAL;
482 }
483 return 0;
484}
485
486static umode_t lm75_is_visible(const void *data, enum hwmon_sensor_types type,
487 u32 attr, int channel)
488{
489 const struct lm75_data *config_data = data;
490
491 switch (type) {
492 case hwmon_chip:
493 switch (attr) {
494 case hwmon_chip_update_interval:
495 if (config_data->params->num_sample_times > 1)
496 return 0644;
497 return 0444;
498 }
499 break;
500 case hwmon_temp:
501 switch (attr) {
502 case hwmon_temp_input:
503 return 0444;
504 case hwmon_temp_max:
505 case hwmon_temp_max_hyst:
506 return 0644;
507 }
508 break;
509 default:
510 break;
511 }
512 return 0;
513}
514
515static const struct hwmon_channel_info *lm75_info[] = {
516 HWMON_CHANNEL_INFO(chip,
517 HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL),
518 HWMON_CHANNEL_INFO(temp,
519 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST),
520 NULL
521};
522
523static const struct hwmon_ops lm75_hwmon_ops = {
524 .is_visible = lm75_is_visible,
525 .read = lm75_read,
526 .write = lm75_write,
527};
528
529static const struct hwmon_chip_info lm75_chip_info = {
530 .ops = &lm75_hwmon_ops,
531 .info = lm75_info,
532};
533
534static bool lm75_is_writeable_reg(struct device *dev, unsigned int reg)
535{
536 return reg != LM75_REG_TEMP;
537}
538
539static bool lm75_is_volatile_reg(struct device *dev, unsigned int reg)
540{
541 return reg == LM75_REG_TEMP || reg == LM75_REG_CONF;
542}
543
544static const struct regmap_config lm75_regmap_config = {
545 .reg_bits = 8,
546 .val_bits = 16,
547 .max_register = PCT2075_REG_IDLE,
548 .writeable_reg = lm75_is_writeable_reg,
549 .volatile_reg = lm75_is_volatile_reg,
550 .val_format_endian = REGMAP_ENDIAN_BIG,
551 .cache_type = REGCACHE_RBTREE,
552 .use_single_read = true,
553 .use_single_write = true,
554};
555
556static void lm75_disable_regulator(void *data)
557{
558 struct lm75_data *lm75 = data;
559
560 regulator_disable(lm75->vs);
561}
562
563static void lm75_remove(void *data)
564{
565 struct lm75_data *lm75 = data;
566 struct i2c_client *client = lm75->client;
567
568 i2c_smbus_write_byte_data(client, LM75_REG_CONF, lm75->orig_conf);
569}
570
571static const struct i2c_device_id lm75_ids[];
572
573static int lm75_probe(struct i2c_client *client)
574{
575 struct device *dev = &client->dev;
576 struct device *hwmon_dev;
577 struct lm75_data *data;
578 int status, err;
579 enum lm75_type kind;
580
581 if (client->dev.of_node)
582 kind = (enum lm75_type)of_device_get_match_data(&client->dev);
583 else
584 kind = i2c_match_id(lm75_ids, client)->driver_data;
585
586 if (!i2c_check_functionality(client->adapter,
587 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
588 return -EIO;
589
590 data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
591 if (!data)
592 return -ENOMEM;
593
594 data->client = client;
595 data->kind = kind;
596
597 data->vs = devm_regulator_get(dev, "vs");
598 if (IS_ERR(data->vs))
599 return PTR_ERR(data->vs);
600
601 data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
602 if (IS_ERR(data->regmap))
603 return PTR_ERR(data->regmap);
604
605 /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
606 * Then tweak to be more precise when appropriate.
607 */
608
609 data->params = &device_params[data->kind];
610
611 /* Save default sample time and resolution*/
612 data->sample_time = data->params->default_sample_time;
613 data->resolution = data->params->default_resolution;
614
615 /* Enable the power */
616 err = regulator_enable(data->vs);
617 if (err) {
618 dev_err(dev, "failed to enable regulator: %d\n", err);
619 return err;
620 }
621
622 err = devm_add_action_or_reset(dev, lm75_disable_regulator, data);
623 if (err)
624 return err;
625
626 /* Cache original configuration */
627 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
628 if (status < 0) {
629 dev_dbg(dev, "Can't read config? %d\n", status);
630 return status;
631 }
632 data->orig_conf = status;
633 data->current_conf = status;
634
635 err = lm75_write_config(data, data->params->set_mask,
636 data->params->clr_mask);
637 if (err)
638 return err;
639
640 err = devm_add_action_or_reset(dev, lm75_remove, data);
641 if (err)
642 return err;
643
644 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
645 data, &lm75_chip_info,
646 NULL);
647 if (IS_ERR(hwmon_dev))
648 return PTR_ERR(hwmon_dev);
649
650 dev_info(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), client->name);
651
652 return 0;
653}
654
655static const struct i2c_device_id lm75_ids[] = {
656 { "adt75", adt75, },
657 { "at30ts74", at30ts74, },
658 { "ds1775", ds1775, },
659 { "ds75", ds75, },
660 { "ds7505", ds7505, },
661 { "g751", g751, },
662 { "lm75", lm75, },
663 { "lm75a", lm75a, },
664 { "lm75b", lm75b, },
665 { "max6625", max6625, },
666 { "max6626", max6626, },
667 { "max31725", max31725, },
668 { "max31726", max31725, },
669 { "mcp980x", mcp980x, },
670 { "pct2075", pct2075, },
671 { "stds75", stds75, },
672 { "stlm75", stlm75, },
673 { "tcn75", tcn75, },
674 { "tmp100", tmp100, },
675 { "tmp101", tmp101, },
676 { "tmp105", tmp105, },
677 { "tmp112", tmp112, },
678 { "tmp175", tmp175, },
679 { "tmp275", tmp275, },
680 { "tmp75", tmp75, },
681 { "tmp75b", tmp75b, },
682 { "tmp75c", tmp75c, },
683 { "tmp1075", tmp1075, },
684 { /* LIST END */ }
685};
686MODULE_DEVICE_TABLE(i2c, lm75_ids);
687
688static const struct of_device_id __maybe_unused lm75_of_match[] = {
689 {
690 .compatible = "adi,adt75",
691 .data = (void *)adt75
692 },
693 {
694 .compatible = "atmel,at30ts74",
695 .data = (void *)at30ts74
696 },
697 {
698 .compatible = "dallas,ds1775",
699 .data = (void *)ds1775
700 },
701 {
702 .compatible = "dallas,ds75",
703 .data = (void *)ds75
704 },
705 {
706 .compatible = "dallas,ds7505",
707 .data = (void *)ds7505
708 },
709 {
710 .compatible = "gmt,g751",
711 .data = (void *)g751
712 },
713 {
714 .compatible = "national,lm75",
715 .data = (void *)lm75
716 },
717 {
718 .compatible = "national,lm75a",
719 .data = (void *)lm75a
720 },
721 {
722 .compatible = "national,lm75b",
723 .data = (void *)lm75b
724 },
725 {
726 .compatible = "maxim,max6625",
727 .data = (void *)max6625
728 },
729 {
730 .compatible = "maxim,max6626",
731 .data = (void *)max6626
732 },
733 {
734 .compatible = "maxim,max31725",
735 .data = (void *)max31725
736 },
737 {
738 .compatible = "maxim,max31726",
739 .data = (void *)max31725
740 },
741 {
742 .compatible = "maxim,mcp980x",
743 .data = (void *)mcp980x
744 },
745 {
746 .compatible = "nxp,pct2075",
747 .data = (void *)pct2075
748 },
749 {
750 .compatible = "st,stds75",
751 .data = (void *)stds75
752 },
753 {
754 .compatible = "st,stlm75",
755 .data = (void *)stlm75
756 },
757 {
758 .compatible = "microchip,tcn75",
759 .data = (void *)tcn75
760 },
761 {
762 .compatible = "ti,tmp100",
763 .data = (void *)tmp100
764 },
765 {
766 .compatible = "ti,tmp101",
767 .data = (void *)tmp101
768 },
769 {
770 .compatible = "ti,tmp105",
771 .data = (void *)tmp105
772 },
773 {
774 .compatible = "ti,tmp112",
775 .data = (void *)tmp112
776 },
777 {
778 .compatible = "ti,tmp175",
779 .data = (void *)tmp175
780 },
781 {
782 .compatible = "ti,tmp275",
783 .data = (void *)tmp275
784 },
785 {
786 .compatible = "ti,tmp75",
787 .data = (void *)tmp75
788 },
789 {
790 .compatible = "ti,tmp75b",
791 .data = (void *)tmp75b
792 },
793 {
794 .compatible = "ti,tmp75c",
795 .data = (void *)tmp75c
796 },
797 {
798 .compatible = "ti,tmp1075",
799 .data = (void *)tmp1075
800 },
801 { },
802};
803MODULE_DEVICE_TABLE(of, lm75_of_match);
804
805#define LM75A_ID 0xA1
806
807/* Return 0 if detection is successful, -ENODEV otherwise */
808static int lm75_detect(struct i2c_client *new_client,
809 struct i2c_board_info *info)
810{
811 struct i2c_adapter *adapter = new_client->adapter;
812 int i;
813 int conf, hyst, os;
814 bool is_lm75a = 0;
815
816 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
817 I2C_FUNC_SMBUS_WORD_DATA))
818 return -ENODEV;
819
820 /*
821 * Now, we do the remaining detection. There is no identification-
822 * dedicated register so we have to rely on several tricks:
823 * unused bits, registers cycling over 8-address boundaries,
824 * addresses 0x04-0x07 returning the last read value.
825 * The cycling+unused addresses combination is not tested,
826 * since it would significantly slow the detection down and would
827 * hardly add any value.
828 *
829 * The National Semiconductor LM75A is different than earlier
830 * LM75s. It has an ID byte of 0xaX (where X is the chip
831 * revision, with 1 being the only revision in existence) in
832 * register 7, and unused registers return 0xff rather than the
833 * last read value.
834 *
835 * Note that this function only detects the original National
836 * Semiconductor LM75 and the LM75A. Clones from other vendors
837 * aren't detected, on purpose, because they are typically never
838 * found on PC hardware. They are found on embedded designs where
839 * they can be instantiated explicitly so detection is not needed.
840 * The absence of identification registers on all these clones
841 * would make their exhaustive detection very difficult and weak,
842 * and odds are that the driver would bind to unsupported devices.
843 */
844
845 /* Unused bits */
846 conf = i2c_smbus_read_byte_data(new_client, 1);
847 if (conf & 0xe0)
848 return -ENODEV;
849
850 /* First check for LM75A */
851 if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
852 /*
853 * LM75A returns 0xff on unused registers so
854 * just to be sure we check for that too.
855 */
856 if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
857 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
858 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
859 return -ENODEV;
860 is_lm75a = 1;
861 hyst = i2c_smbus_read_byte_data(new_client, 2);
862 os = i2c_smbus_read_byte_data(new_client, 3);
863 } else { /* Traditional style LM75 detection */
864 /* Unused addresses */
865 hyst = i2c_smbus_read_byte_data(new_client, 2);
866 if (i2c_smbus_read_byte_data(new_client, 4) != hyst
867 || i2c_smbus_read_byte_data(new_client, 5) != hyst
868 || i2c_smbus_read_byte_data(new_client, 6) != hyst
869 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
870 return -ENODEV;
871 os = i2c_smbus_read_byte_data(new_client, 3);
872 if (i2c_smbus_read_byte_data(new_client, 4) != os
873 || i2c_smbus_read_byte_data(new_client, 5) != os
874 || i2c_smbus_read_byte_data(new_client, 6) != os
875 || i2c_smbus_read_byte_data(new_client, 7) != os)
876 return -ENODEV;
877 }
878 /*
879 * It is very unlikely that this is a LM75 if both
880 * hysteresis and temperature limit registers are 0.
881 */
882 if (hyst == 0 && os == 0)
883 return -ENODEV;
884
885 /* Addresses cycling */
886 for (i = 8; i <= 248; i += 40) {
887 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
888 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
889 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
890 return -ENODEV;
891 if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
892 != LM75A_ID)
893 return -ENODEV;
894 }
895
896 strscpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
897
898 return 0;
899}
900
901#ifdef CONFIG_PM
902static int lm75_suspend(struct device *dev)
903{
904 int status;
905 struct i2c_client *client = to_i2c_client(dev);
906
907 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
908 if (status < 0) {
909 dev_dbg(&client->dev, "Can't read config? %d\n", status);
910 return status;
911 }
912 status = status | LM75_SHUTDOWN;
913 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
914 return 0;
915}
916
917static int lm75_resume(struct device *dev)
918{
919 int status;
920 struct i2c_client *client = to_i2c_client(dev);
921
922 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
923 if (status < 0) {
924 dev_dbg(&client->dev, "Can't read config? %d\n", status);
925 return status;
926 }
927 status = status & ~LM75_SHUTDOWN;
928 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
929 return 0;
930}
931
932static const struct dev_pm_ops lm75_dev_pm_ops = {
933 .suspend = lm75_suspend,
934 .resume = lm75_resume,
935};
936#define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
937#else
938#define LM75_DEV_PM_OPS NULL
939#endif /* CONFIG_PM */
940
941static struct i2c_driver lm75_driver = {
942 .class = I2C_CLASS_HWMON,
943 .driver = {
944 .name = "lm75",
945 .of_match_table = of_match_ptr(lm75_of_match),
946 .pm = LM75_DEV_PM_OPS,
947 },
948 .probe_new = lm75_probe,
949 .id_table = lm75_ids,
950 .detect = lm75_detect,
951 .address_list = normal_i2c,
952};
953
954module_i2c_driver(lm75_driver);
955
956MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
957MODULE_DESCRIPTION("LM75 driver");
958MODULE_LICENSE("GPL");