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Linux 6.13-rc6
[linux.git] / drivers / hwmon / lm75.c
blob2c2205aec7d40b92f248976221c4497766d88df9
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/interrupt.h>
11 #include <linux/slab.h>
12 #include <linux/jiffies.h>
13 #include <linux/i2c.h>
14 #include <linux/hwmon.h>
15 #include <linux/err.h>
16 #include <linux/of.h>
17 #include <linux/regmap.h>
18 #include <linux/util_macros.h>
19 #include <linux/regulator/consumer.h>
20 #include "lm75.h"
21
22 /*
23 * This driver handles the LM75 and compatible digital temperature sensors.
24 */
25
26 enum lm75_type { /* keep sorted in alphabetical order */
27 adt75,
28 as6200,
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 * @config_reg_16bits: Configure register size is 2 bytes.
60 * @set_mask: Bits to set in configuration register when configuring
61 * the chip.
62 * @clr_mask: Bits to clear in configuration register when configuring
63 * the chip.
64 * @default_resolution: Default number of bits to represent the temperature
65 * value.
66 * @resolution_limits: Limit register resolution. Optional. Should be set if
67 * the resolution of limit registers does not match the
68 * resolution of the temperature register.
69 * @resolutions: List of resolutions associated with sample times.
70 * Optional. Should be set if num_sample_times is larger
71 * than 1, and if the resolution changes with sample times.
72 * If set, number of entries must match num_sample_times.
73 * @default_sample_time:Sample time to be set by default.
74 * @num_sample_times: Number of possible sample times to be set. Optional.
75 * Should be set if the number of sample times is larger
76 * than one.
77 * @sample_times: All the possible sample times to be set. Mandatory if
78 * num_sample_times is larger than 1. If set, number of
79 * entries must match num_sample_times.
80 * @alarm: Alarm bit is supported.
81 */
82
83 struct lm75_params {
84 bool config_reg_16bits;
85 u16 set_mask;
86 u16 clr_mask;
87 u8 default_resolution;
88 u8 resolution_limits;
89 const u8 *resolutions;
90 unsigned int default_sample_time;
91 u8 num_sample_times;
92 const unsigned int *sample_times;
93 bool alarm;
94 };
95
96 /* Addresses scanned */
97 static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, 0x4c,
98 0x4d, 0x4e, 0x4f, I2C_CLIENT_END };
99
100 /* The LM75 registers */
101 #define LM75_REG_TEMP 0x00
102 #define LM75_REG_CONF 0x01
103 #define LM75_REG_HYST 0x02
104 #define LM75_REG_MAX 0x03
105 #define PCT2075_REG_IDLE 0x04
106
107 /* Each client has this additional data */
108 struct lm75_data {
109 struct i2c_client *client;
110 struct regmap *regmap;
111 struct regulator *vs;
112 u16 orig_conf;
113 u16 current_conf;
114 u8 resolution; /* In bits, 9 to 16 */
115 unsigned int sample_time; /* In ms */
116 enum lm75_type kind;
117 const struct lm75_params *params;
118 };
119
120 /*-----------------------------------------------------------------------*/
121
122 static const u8 lm75_sample_set_masks[] = { 0 << 5, 1 << 5, 2 << 5, 3 << 5 };
123
124 #define LM75_SAMPLE_CLEAR_MASK (3 << 5)
125
126 /* The structure below stores the configuration values of the supported devices.
127 * In case of being supported multiple configurations, the default one must
128 * always be the first element of the array
129 */
130 static const struct lm75_params device_params[] = {
131 [adt75] = {
132 .clr_mask = 1 << 5, /* not one-shot mode */
133 .default_resolution = 12,
134 .default_sample_time = MSEC_PER_SEC / 10,
135 },
136 [as6200] = {
137 .config_reg_16bits = true,
138 .set_mask = 0x94C0, /* 8 sample/s, 4 CF, positive polarity */
139 .default_resolution = 12,
140 .default_sample_time = 125,
141 .num_sample_times = 4,
142 .sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
143 .alarm = true,
144 },
145 [at30ts74] = {
146 .set_mask = 3 << 5, /* 12-bit mode*/
147 .default_resolution = 12,
148 .default_sample_time = 200,
149 .num_sample_times = 4,
150 .sample_times = (unsigned int []){ 25, 50, 100, 200 },
151 .resolutions = (u8 []) {9, 10, 11, 12 },
152 },
153 [ds1775] = {
154 .clr_mask = 3 << 5,
155 .set_mask = 2 << 5, /* 11-bit mode */
156 .default_resolution = 11,
157 .default_sample_time = 500,
158 .num_sample_times = 4,
159 .sample_times = (unsigned int []){ 125, 250, 500, 1000 },
160 .resolutions = (u8 []) {9, 10, 11, 12 },
161 },
162 [ds75] = {
163 .clr_mask = 3 << 5,
164 .set_mask = 2 << 5, /* 11-bit mode */
165 .default_resolution = 11,
166 .default_sample_time = 600,
167 .num_sample_times = 4,
168 .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
169 .resolutions = (u8 []) {9, 10, 11, 12 },
170 },
171 [stds75] = {
172 .clr_mask = 3 << 5,
173 .set_mask = 2 << 5, /* 11-bit mode */
174 .default_resolution = 11,
175 .default_sample_time = 600,
176 .num_sample_times = 4,
177 .sample_times = (unsigned int []){ 150, 300, 600, 1200 },
178 .resolutions = (u8 []) {9, 10, 11, 12 },
179 },
180 [stlm75] = {
181 .default_resolution = 9,
182 .default_sample_time = MSEC_PER_SEC / 6,
183 },
184 [ds7505] = {
185 .set_mask = 3 << 5, /* 12-bit mode*/
186 .default_resolution = 12,
187 .default_sample_time = 200,
188 .num_sample_times = 4,
189 .sample_times = (unsigned int []){ 25, 50, 100, 200 },
190 .resolutions = (u8 []) {9, 10, 11, 12 },
191 },
192 [g751] = {
193 .default_resolution = 9,
194 .default_sample_time = MSEC_PER_SEC / 10,
195 },
196 [lm75] = {
197 .default_resolution = 9,
198 .default_sample_time = MSEC_PER_SEC / 10,
199 },
200 [lm75a] = {
201 .default_resolution = 9,
202 .default_sample_time = MSEC_PER_SEC / 10,
203 },
204 [lm75b] = {
205 .default_resolution = 11,
206 .default_sample_time = MSEC_PER_SEC / 10,
207 },
208 [max6625] = {
209 .default_resolution = 9,
210 .default_sample_time = MSEC_PER_SEC / 7,
211 },
212 [max6626] = {
213 .default_resolution = 12,
214 .default_sample_time = MSEC_PER_SEC / 7,
215 .resolution_limits = 9,
216 },
217 [max31725] = {
218 .default_resolution = 16,
219 .default_sample_time = MSEC_PER_SEC / 20,
220 },
221 [tcn75] = {
222 .default_resolution = 9,
223 .default_sample_time = MSEC_PER_SEC / 18,
224 },
225 [pct2075] = {
226 .default_resolution = 11,
227 .default_sample_time = MSEC_PER_SEC / 10,
228 .num_sample_times = 31,
229 .sample_times = (unsigned int []){ 100, 200, 300, 400, 500, 600,
230 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700,
231 1800, 1900, 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700,
232 2800, 2900, 3000, 3100 },
233 },
234 [mcp980x] = {
235 .set_mask = 3 << 5, /* 12-bit mode */
236 .clr_mask = 1 << 7, /* not one-shot mode */
237 .default_resolution = 12,
238 .resolution_limits = 9,
239 .default_sample_time = 240,
240 .num_sample_times = 4,
241 .sample_times = (unsigned int []){ 30, 60, 120, 240 },
242 .resolutions = (u8 []) {9, 10, 11, 12 },
243 },
244 [tmp100] = {
245 .set_mask = 3 << 5, /* 12-bit mode */
246 .clr_mask = 1 << 7, /* not one-shot mode */
247 .default_resolution = 12,
248 .default_sample_time = 320,
249 .num_sample_times = 4,
250 .sample_times = (unsigned int []){ 40, 80, 160, 320 },
251 .resolutions = (u8 []) {9, 10, 11, 12 },
252 },
253 [tmp101] = {
254 .set_mask = 3 << 5, /* 12-bit mode */
255 .clr_mask = 1 << 7, /* not one-shot mode */
256 .default_resolution = 12,
257 .default_sample_time = 320,
258 .num_sample_times = 4,
259 .sample_times = (unsigned int []){ 40, 80, 160, 320 },
260 .resolutions = (u8 []) {9, 10, 11, 12 },
261 },
262 [tmp105] = {
263 .set_mask = 3 << 5, /* 12-bit mode */
264 .clr_mask = 1 << 7, /* not one-shot mode*/
265 .default_resolution = 12,
266 .default_sample_time = 220,
267 .num_sample_times = 4,
268 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
269 .resolutions = (u8 []) {9, 10, 11, 12 },
270 },
271 [tmp112] = {
272 .config_reg_16bits = true,
273 .set_mask = 0x60C0, /* 12-bit mode, 8 samples / second */
274 .clr_mask = 1 << 15, /* no one-shot mode*/
275 .default_resolution = 12,
276 .default_sample_time = 125,
277 .num_sample_times = 4,
278 .sample_times = (unsigned int []){ 125, 250, 1000, 4000 },
279 },
280 [tmp175] = {
281 .set_mask = 3 << 5, /* 12-bit mode */
282 .clr_mask = 1 << 7, /* not one-shot mode*/
283 .default_resolution = 12,
284 .default_sample_time = 220,
285 .num_sample_times = 4,
286 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
287 .resolutions = (u8 []) {9, 10, 11, 12 },
288 },
289 [tmp275] = {
290 .set_mask = 3 << 5, /* 12-bit mode */
291 .clr_mask = 1 << 7, /* not one-shot mode*/
292 .default_resolution = 12,
293 .default_sample_time = 220,
294 .num_sample_times = 4,
295 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
296 .resolutions = (u8 []) {9, 10, 11, 12 },
297 },
298 [tmp75] = {
299 .set_mask = 3 << 5, /* 12-bit mode */
300 .clr_mask = 1 << 7, /* not one-shot mode*/
301 .default_resolution = 12,
302 .default_sample_time = 220,
303 .num_sample_times = 4,
304 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
305 .resolutions = (u8 []) {9, 10, 11, 12 },
306 },
307 [tmp75b] = { /* not one-shot mode, Conversion rate 37Hz */
308 .clr_mask = 1 << 7 | 3 << 5,
309 .default_resolution = 12,
310 .default_sample_time = MSEC_PER_SEC / 37,
311 .sample_times = (unsigned int []){ MSEC_PER_SEC / 37,
312 MSEC_PER_SEC / 18,
313 MSEC_PER_SEC / 9, MSEC_PER_SEC / 4 },
314 .num_sample_times = 4,
315 },
316 [tmp75c] = {
317 .clr_mask = 1 << 5, /*not one-shot mode*/
318 .default_resolution = 12,
319 .default_sample_time = MSEC_PER_SEC / 12,
320 },
321 [tmp1075] = { /* not one-shot mode, 27.5 ms sample rate */
322 .clr_mask = 1 << 5 | 1 << 6 | 1 << 7,
323 .default_resolution = 12,
324 .default_sample_time = 28,
325 .num_sample_times = 4,
326 .sample_times = (unsigned int []){ 28, 55, 110, 220 },
327 }
328 };
329
330 static inline long lm75_reg_to_mc(s16 temp, u8 resolution)
331 {
332 return ((temp >> (16 - resolution)) * 1000) >> (resolution - 8);
333 }
334
335 static int lm75_write_config(struct lm75_data *data, u16 set_mask,
336 u16 clr_mask)
337 {
338 unsigned int value;
339
340 clr_mask |= LM75_SHUTDOWN << (8 * data->params->config_reg_16bits);
341 value = data->current_conf & ~clr_mask;
342 value |= set_mask;
343
344 if (data->current_conf != value) {
345 s32 err;
346 if (data->params->config_reg_16bits)
347 err = regmap_write(data->regmap, LM75_REG_CONF, value);
348 else
349 err = i2c_smbus_write_byte_data(data->client,
350 LM75_REG_CONF,
351 value);
352 if (err)
353 return err;
354 data->current_conf = value;
355 }
356 return 0;
357 }
358
359 static int lm75_read_config(struct lm75_data *data)
360 {
361 int ret;
362 unsigned int status;
363
364 if (data->params->config_reg_16bits) {
365 ret = regmap_read(data->regmap, LM75_REG_CONF, &status);
366 return ret ? ret : status;
367 }
368
369 return i2c_smbus_read_byte_data(data->client, LM75_REG_CONF);
370 }
371
372 static irqreturn_t lm75_alarm_handler(int irq, void *private)
373 {
374 struct device *hwmon_dev = private;
375
376 hwmon_notify_event(hwmon_dev, hwmon_temp, hwmon_temp_alarm, 0);
377 return IRQ_HANDLED;
378 }
379
380 static int lm75_read(struct device *dev, enum hwmon_sensor_types type,
381 u32 attr, int channel, long *val)
382 {
383 struct lm75_data *data = dev_get_drvdata(dev);
384 unsigned int regval;
385 int err, reg;
386
387 switch (type) {
388 case hwmon_chip:
389 switch (attr) {
390 case hwmon_chip_update_interval:
391 *val = data->sample_time;
392 break;
393 default:
394 return -EINVAL;
395 }
396 break;
397 case hwmon_temp:
398 switch (attr) {
399 case hwmon_temp_input:
400 reg = LM75_REG_TEMP;
401 break;
402 case hwmon_temp_max:
403 reg = LM75_REG_MAX;
404 break;
405 case hwmon_temp_max_hyst:
406 reg = LM75_REG_HYST;
407 break;
408 case hwmon_temp_alarm:
409 reg = LM75_REG_CONF;
410 break;
411 default:
412 return -EINVAL;
413 }
414 err = regmap_read(data->regmap, reg, &regval);
415 if (err < 0)
416 return err;
417
418 if (attr == hwmon_temp_alarm) {
419 switch (data->kind) {
420 case as6200:
421 *val = (regval >> 5) & 0x1;
422 break;
423 default:
424 return -EINVAL;
425 }
426 } else {
427 *val = lm75_reg_to_mc(regval, data->resolution);
428 }
429 break;
430 default:
431 return -EINVAL;
432 }
433 return 0;
434 }
435
436 static int lm75_write_temp(struct device *dev, u32 attr, long temp)
437 {
438 struct lm75_data *data = dev_get_drvdata(dev);
439 u8 resolution;
440 int reg;
441
442 switch (attr) {
443 case hwmon_temp_max:
444 reg = LM75_REG_MAX;
445 break;
446 case hwmon_temp_max_hyst:
447 reg = LM75_REG_HYST;
448 break;
449 default:
450 return -EINVAL;
451 }
452
453 /*
454 * Resolution of limit registers is assumed to be the same as the
455 * temperature input register resolution unless given explicitly.
456 */
457 if (data->params->resolution_limits)
458 resolution = data->params->resolution_limits;
459 else
460 resolution = data->resolution;
461
462 temp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
463 temp = DIV_ROUND_CLOSEST(temp << (resolution - 8),
464 1000) << (16 - resolution);
465
466 return regmap_write(data->regmap, reg, (u16)temp);
467 }
468
469 static int lm75_update_interval(struct device *dev, long val)
470 {
471 struct lm75_data *data = dev_get_drvdata(dev);
472 unsigned int reg;
473 u8 index;
474 s32 err;
475
476 index = find_closest(val, data->params->sample_times,
477 (int)data->params->num_sample_times);
478
479 switch (data->kind) {
480 default:
481 err = lm75_write_config(data, lm75_sample_set_masks[index],
482 LM75_SAMPLE_CLEAR_MASK);
483 if (err)
484 return err;
485
486 data->sample_time = data->params->sample_times[index];
487 if (data->params->resolutions)
488 data->resolution = data->params->resolutions[index];
489 break;
490 case tmp112:
491 case as6200:
492 err = regmap_read(data->regmap, LM75_REG_CONF, &reg);
493 if (err < 0)
494 return err;
495 reg &= ~0x00c0;
496 reg |= (3 - index) << 6;
497 err = regmap_write(data->regmap, LM75_REG_CONF, reg);
498 if (err < 0)
499 return err;
500 data->sample_time = data->params->sample_times[index];
501 break;
502 case pct2075:
503 err = i2c_smbus_write_byte_data(data->client, PCT2075_REG_IDLE,
504 index + 1);
505 if (err)
506 return err;
507 data->sample_time = data->params->sample_times[index];
508 break;
509 }
510 return 0;
511 }
512
513 static int lm75_write_chip(struct device *dev, u32 attr, long val)
514 {
515 switch (attr) {
516 case hwmon_chip_update_interval:
517 return lm75_update_interval(dev, val);
518 default:
519 return -EINVAL;
520 }
521 return 0;
522 }
523
524 static int lm75_write(struct device *dev, enum hwmon_sensor_types type,
525 u32 attr, int channel, long val)
526 {
527 switch (type) {
528 case hwmon_chip:
529 return lm75_write_chip(dev, attr, val);
530 case hwmon_temp:
531 return lm75_write_temp(dev, attr, val);
532 default:
533 return -EINVAL;
534 }
535 return 0;
536 }
537
538 static umode_t lm75_is_visible(const void *data, enum hwmon_sensor_types type,
539 u32 attr, int channel)
540 {
541 const struct lm75_data *config_data = data;
542
543 switch (type) {
544 case hwmon_chip:
545 switch (attr) {
546 case hwmon_chip_update_interval:
547 if (config_data->params->num_sample_times > 1)
548 return 0644;
549 return 0444;
550 }
551 break;
552 case hwmon_temp:
553 switch (attr) {
554 case hwmon_temp_input:
555 return 0444;
556 case hwmon_temp_max:
557 case hwmon_temp_max_hyst:
558 return 0644;
559 case hwmon_temp_alarm:
560 if (config_data->params->alarm)
561 return 0444;
562 break;
563 }
564 break;
565 default:
566 break;
567 }
568 return 0;
569 }
570
571 static const struct hwmon_channel_info * const lm75_info[] = {
572 HWMON_CHANNEL_INFO(chip,
573 HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL),
574 HWMON_CHANNEL_INFO(temp,
575 HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST |
576 HWMON_T_ALARM),
577 NULL
578 };
579
580 static const struct hwmon_ops lm75_hwmon_ops = {
581 .is_visible = lm75_is_visible,
582 .read = lm75_read,
583 .write = lm75_write,
584 };
585
586 static const struct hwmon_chip_info lm75_chip_info = {
587 .ops = &lm75_hwmon_ops,
588 .info = lm75_info,
589 };
590
591 static bool lm75_is_writeable_reg(struct device *dev, unsigned int reg)
592 {
593 return reg != LM75_REG_TEMP;
594 }
595
596 static bool lm75_is_volatile_reg(struct device *dev, unsigned int reg)
597 {
598 return reg == LM75_REG_TEMP || reg == LM75_REG_CONF;
599 }
600
601 static const struct regmap_config lm75_regmap_config = {
602 .reg_bits = 8,
603 .val_bits = 16,
604 .max_register = PCT2075_REG_IDLE,
605 .writeable_reg = lm75_is_writeable_reg,
606 .volatile_reg = lm75_is_volatile_reg,
607 .val_format_endian = REGMAP_ENDIAN_BIG,
608 .cache_type = REGCACHE_MAPLE,
609 .use_single_read = true,
610 .use_single_write = true,
611 };
612
613 static void lm75_disable_regulator(void *data)
614 {
615 struct lm75_data *lm75 = data;
616
617 regulator_disable(lm75->vs);
618 }
619
620 static void lm75_remove(void *data)
621 {
622 struct lm75_data *lm75 = data;
623 struct i2c_client *client = lm75->client;
624
625 i2c_smbus_write_byte_data(client, LM75_REG_CONF, lm75->orig_conf);
626 }
627
628 static int lm75_probe(struct i2c_client *client)
629 {
630 struct device *dev = &client->dev;
631 struct device *hwmon_dev;
632 struct lm75_data *data;
633 int status, err;
634
635 if (!i2c_check_functionality(client->adapter,
636 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))
637 return -EIO;
638
639 data = devm_kzalloc(dev, sizeof(struct lm75_data), GFP_KERNEL);
640 if (!data)
641 return -ENOMEM;
642
643 data->client = client;
644 data->kind = (uintptr_t)i2c_get_match_data(client);
645
646 data->vs = devm_regulator_get(dev, "vs");
647 if (IS_ERR(data->vs))
648 return PTR_ERR(data->vs);
649
650 data->regmap = devm_regmap_init_i2c(client, &lm75_regmap_config);
651 if (IS_ERR(data->regmap))
652 return PTR_ERR(data->regmap);
653
654 /* Set to LM75 resolution (9 bits, 1/2 degree C) and range.
655 * Then tweak to be more precise when appropriate.
656 */
657
658 data->params = &device_params[data->kind];
659
660 /* Save default sample time and resolution*/
661 data->sample_time = data->params->default_sample_time;
662 data->resolution = data->params->default_resolution;
663
664 /* Enable the power */
665 err = regulator_enable(data->vs);
666 if (err) {
667 dev_err(dev, "failed to enable regulator: %d\n", err);
668 return err;
669 }
670
671 err = devm_add_action_or_reset(dev, lm75_disable_regulator, data);
672 if (err)
673 return err;
674
675 /* Cache original configuration */
676 status = lm75_read_config(data);
677 if (status < 0) {
678 dev_dbg(dev, "Can't read config? %d\n", status);
679 return status;
680 }
681 data->orig_conf = status;
682 data->current_conf = status;
683
684 err = lm75_write_config(data, data->params->set_mask,
685 data->params->clr_mask);
686 if (err)
687 return err;
688
689 err = devm_add_action_or_reset(dev, lm75_remove, data);
690 if (err)
691 return err;
692
693 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
694 data, &lm75_chip_info,
695 NULL);
696 if (IS_ERR(hwmon_dev))
697 return PTR_ERR(hwmon_dev);
698
699 if (client->irq) {
700 if (data->params->alarm) {
701 err = devm_request_threaded_irq(dev,
702 client->irq,
703 NULL,
704 &lm75_alarm_handler,
705 IRQF_ONESHOT,
706 client->name,
707 hwmon_dev);
708 if (err)
709 return err;
710 } else {
711 /* alarm is only supported for chips with alarm bit */
712 dev_err(dev, "alarm interrupt is not supported\n");
713 }
714 }
715
716 dev_info(dev, "%s: sensor '%s'\n", dev_name(hwmon_dev), client->name);
717
718 return 0;
719 }
720
721 static const struct i2c_device_id lm75_ids[] = {
722 { "adt75", adt75, },
723 { "as6200", as6200, },
724 { "at30ts74", at30ts74, },
725 { "ds1775", ds1775, },
726 { "ds75", ds75, },
727 { "ds7505", ds7505, },
728 { "g751", g751, },
729 { "lm75", lm75, },
730 { "lm75a", lm75a, },
731 { "lm75b", lm75b, },
732 { "max6625", max6625, },
733 { "max6626", max6626, },
734 { "max31725", max31725, },
735 { "max31726", max31725, },
736 { "mcp980x", mcp980x, },
737 { "pct2075", pct2075, },
738 { "stds75", stds75, },
739 { "stlm75", stlm75, },
740 { "tcn75", tcn75, },
741 { "tmp100", tmp100, },
742 { "tmp101", tmp101, },
743 { "tmp105", tmp105, },
744 { "tmp112", tmp112, },
745 { "tmp175", tmp175, },
746 { "tmp275", tmp275, },
747 { "tmp75", tmp75, },
748 { "tmp75b", tmp75b, },
749 { "tmp75c", tmp75c, },
750 { "tmp1075", tmp1075, },
751 { /* LIST END */ }
752 };
753 MODULE_DEVICE_TABLE(i2c, lm75_ids);
754
755 static const struct of_device_id __maybe_unused lm75_of_match[] = {
756 {
757 .compatible = "adi,adt75",
758 .data = (void *)adt75
759 },
760 {
761 .compatible = "ams,as6200",
762 .data = (void *)as6200
763 },
764 {
765 .compatible = "atmel,at30ts74",
766 .data = (void *)at30ts74
767 },
768 {
769 .compatible = "dallas,ds1775",
770 .data = (void *)ds1775
771 },
772 {
773 .compatible = "dallas,ds75",
774 .data = (void *)ds75
775 },
776 {
777 .compatible = "dallas,ds7505",
778 .data = (void *)ds7505
779 },
780 {
781 .compatible = "gmt,g751",
782 .data = (void *)g751
783 },
784 {
785 .compatible = "national,lm75",
786 .data = (void *)lm75
787 },
788 {
789 .compatible = "national,lm75a",
790 .data = (void *)lm75a
791 },
792 {
793 .compatible = "national,lm75b",
794 .data = (void *)lm75b
795 },
796 {
797 .compatible = "maxim,max6625",
798 .data = (void *)max6625
799 },
800 {
801 .compatible = "maxim,max6626",
802 .data = (void *)max6626
803 },
804 {
805 .compatible = "maxim,max31725",
806 .data = (void *)max31725
807 },
808 {
809 .compatible = "maxim,max31726",
810 .data = (void *)max31725
811 },
812 {
813 .compatible = "maxim,mcp980x",
814 .data = (void *)mcp980x
815 },
816 {
817 .compatible = "nxp,pct2075",
818 .data = (void *)pct2075
819 },
820 {
821 .compatible = "st,stds75",
822 .data = (void *)stds75
823 },
824 {
825 .compatible = "st,stlm75",
826 .data = (void *)stlm75
827 },
828 {
829 .compatible = "microchip,tcn75",
830 .data = (void *)tcn75
831 },
832 {
833 .compatible = "ti,tmp100",
834 .data = (void *)tmp100
835 },
836 {
837 .compatible = "ti,tmp101",
838 .data = (void *)tmp101
839 },
840 {
841 .compatible = "ti,tmp105",
842 .data = (void *)tmp105
843 },
844 {
845 .compatible = "ti,tmp112",
846 .data = (void *)tmp112
847 },
848 {
849 .compatible = "ti,tmp175",
850 .data = (void *)tmp175
851 },
852 {
853 .compatible = "ti,tmp275",
854 .data = (void *)tmp275
855 },
856 {
857 .compatible = "ti,tmp75",
858 .data = (void *)tmp75
859 },
860 {
861 .compatible = "ti,tmp75b",
862 .data = (void *)tmp75b
863 },
864 {
865 .compatible = "ti,tmp75c",
866 .data = (void *)tmp75c
867 },
868 {
869 .compatible = "ti,tmp1075",
870 .data = (void *)tmp1075
871 },
872 { },
873 };
874 MODULE_DEVICE_TABLE(of, lm75_of_match);
875
876 #define LM75A_ID 0xA1
877
878 /* Return 0 if detection is successful, -ENODEV otherwise */
879 static int lm75_detect(struct i2c_client *new_client,
880 struct i2c_board_info *info)
881 {
882 struct i2c_adapter *adapter = new_client->adapter;
883 int i;
884 int conf, hyst, os;
885 bool is_lm75a = 0;
886
887 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
888 I2C_FUNC_SMBUS_WORD_DATA))
889 return -ENODEV;
890
891 /*
892 * Now, we do the remaining detection. There is no identification-
893 * dedicated register so we have to rely on several tricks:
894 * unused bits, registers cycling over 8-address boundaries,
895 * addresses 0x04-0x07 returning the last read value.
896 * The cycling+unused addresses combination is not tested,
897 * since it would significantly slow the detection down and would
898 * hardly add any value.
899 *
900 * The National Semiconductor LM75A is different than earlier
901 * LM75s. It has an ID byte of 0xaX (where X is the chip
902 * revision, with 1 being the only revision in existence) in
903 * register 7, and unused registers return 0xff rather than the
904 * last read value.
905 *
906 * Note that this function only detects the original National
907 * Semiconductor LM75 and the LM75A. Clones from other vendors
908 * aren't detected, on purpose, because they are typically never
909 * found on PC hardware. They are found on embedded designs where
910 * they can be instantiated explicitly so detection is not needed.
911 * The absence of identification registers on all these clones
912 * would make their exhaustive detection very difficult and weak,
913 * and odds are that the driver would bind to unsupported devices.
914 */
915
916 /* Unused bits */
917 conf = i2c_smbus_read_byte_data(new_client, 1);
918 if (conf & 0xe0)
919 return -ENODEV;
920
921 /* First check for LM75A */
922 if (i2c_smbus_read_byte_data(new_client, 7) == LM75A_ID) {
923 /*
924 * LM75A returns 0xff on unused registers so
925 * just to be sure we check for that too.
926 */
927 if (i2c_smbus_read_byte_data(new_client, 4) != 0xff
928 || i2c_smbus_read_byte_data(new_client, 5) != 0xff
929 || i2c_smbus_read_byte_data(new_client, 6) != 0xff)
930 return -ENODEV;
931 is_lm75a = 1;
932 hyst = i2c_smbus_read_byte_data(new_client, 2);
933 os = i2c_smbus_read_byte_data(new_client, 3);
934 } else { /* Traditional style LM75 detection */
935 /* Unused addresses */
936 hyst = i2c_smbus_read_byte_data(new_client, 2);
937 if (i2c_smbus_read_byte_data(new_client, 4) != hyst
938 || i2c_smbus_read_byte_data(new_client, 5) != hyst
939 || i2c_smbus_read_byte_data(new_client, 6) != hyst
940 || i2c_smbus_read_byte_data(new_client, 7) != hyst)
941 return -ENODEV;
942 os = i2c_smbus_read_byte_data(new_client, 3);
943 if (i2c_smbus_read_byte_data(new_client, 4) != os
944 || i2c_smbus_read_byte_data(new_client, 5) != os
945 || i2c_smbus_read_byte_data(new_client, 6) != os
946 || i2c_smbus_read_byte_data(new_client, 7) != os)
947 return -ENODEV;
948 }
949 /*
950 * It is very unlikely that this is a LM75 if both
951 * hysteresis and temperature limit registers are 0.
952 */
953 if (hyst == 0 && os == 0)
954 return -ENODEV;
955
956 /* Addresses cycling */
957 for (i = 8; i <= 248; i += 40) {
958 if (i2c_smbus_read_byte_data(new_client, i + 1) != conf
959 || i2c_smbus_read_byte_data(new_client, i + 2) != hyst
960 || i2c_smbus_read_byte_data(new_client, i + 3) != os)
961 return -ENODEV;
962 if (is_lm75a && i2c_smbus_read_byte_data(new_client, i + 7)
963 != LM75A_ID)
964 return -ENODEV;
965 }
966
967 strscpy(info->type, is_lm75a ? "lm75a" : "lm75", I2C_NAME_SIZE);
968
969 return 0;
970 }
971
972 #ifdef CONFIG_PM
973 static int lm75_suspend(struct device *dev)
974 {
975 int status;
976 struct i2c_client *client = to_i2c_client(dev);
977
978 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
979 if (status < 0) {
980 dev_dbg(&client->dev, "Can't read config? %d\n", status);
981 return status;
982 }
983 status = status | LM75_SHUTDOWN;
984 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
985 return 0;
986 }
987
988 static int lm75_resume(struct device *dev)
989 {
990 int status;
991 struct i2c_client *client = to_i2c_client(dev);
992
993 status = i2c_smbus_read_byte_data(client, LM75_REG_CONF);
994 if (status < 0) {
995 dev_dbg(&client->dev, "Can't read config? %d\n", status);
996 return status;
997 }
998 status = status & ~LM75_SHUTDOWN;
999 i2c_smbus_write_byte_data(client, LM75_REG_CONF, status);
1000 return 0;
1001 }
1002
1003 static const struct dev_pm_ops lm75_dev_pm_ops = {
1004 .suspend = lm75_suspend,
1005 .resume = lm75_resume,
1006 };
1007 #define LM75_DEV_PM_OPS (&lm75_dev_pm_ops)
1008 #else
1009 #define LM75_DEV_PM_OPS NULL
1010 #endif /* CONFIG_PM */
1011
1012 static struct i2c_driver lm75_driver = {
1013 .class = I2C_CLASS_HWMON,
1014 .driver = {
1015 .name = "lm75",
1016 .of_match_table = of_match_ptr(lm75_of_match),
1017 .pm = LM75_DEV_PM_OPS,
1018 },
1019 .probe = lm75_probe,
1020 .id_table = lm75_ids,
1021 .detect = lm75_detect,
1022 .address_list = normal_i2c,
1023 };
1024
1025 module_i2c_driver(lm75_driver);
1026
1027 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
1028 MODULE_DESCRIPTION("LM75 driver");
1029 MODULE_LICENSE("GPL");
Linux Kernel