xref: /linux/drivers/hwmon/spd5118.c (revision 66e72a01b60ae6950ddbb3585fdc1424d303e14b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Driver for Jedec 5118 compliant temperature sensors
4  *
5  * Derived from https://github.com/Steve-Tech/SPD5118-DKMS
6  * Originally from T/2 driver at https://t2sde.org/packages/linux
7  *	Copyright (c) 2023 René Rebe, ExactCODE GmbH; Germany.
8  *
9  * Copyright (c) 2024 Guenter Roeck
10  *
11  * Inspired by ee1004.c and jc42.c.
12  *
13  * SPD5118 compliant temperature sensors are typically used on DDR5
14  * memory modules.
15  */
16 
17 #include <linux/bitops.h>
18 #include <linux/bits.h>
19 #include <linux/err.h>
20 #include <linux/i2c.h>
21 #include <linux/hwmon.h>
22 #include <linux/module.h>
23 #include <linux/mutex.h>
24 #include <linux/nvmem-provider.h>
25 #include <linux/pm.h>
26 #include <linux/regmap.h>
27 #include <linux/units.h>
28 
29 /* Addresses to scan */
30 static const unsigned short normal_i2c[] = {
31 	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, I2C_CLIENT_END };
32 
33 /* SPD5118 registers. */
34 #define SPD5118_REG_TYPE		0x00	/* MR0:MR1 */
35 #define SPD5118_REG_REVISION		0x02	/* MR2 */
36 #define SPD5118_REG_VENDOR		0x03	/* MR3:MR4 */
37 #define SPD5118_REG_CAPABILITY		0x05	/* MR5 */
38 #define SPD5118_REG_I2C_LEGACY_MODE	0x0B	/* MR11 */
39 #define SPD5118_REG_TEMP_CLR		0x13	/* MR19 */
40 #define SPD5118_REG_ERROR_CLR		0x14	/* MR20 */
41 #define SPD5118_REG_TEMP_CONFIG		0x1A	/* MR26 */
42 #define SPD5118_REG_TEMP_MAX		0x1c	/* MR28:MR29 */
43 #define SPD5118_REG_TEMP_MIN		0x1e	/* MR30:MR31 */
44 #define SPD5118_REG_TEMP_CRIT		0x20	/* MR32:MR33 */
45 #define SPD5118_REG_TEMP_LCRIT		0x22	/* MR34:MR35 */
46 #define SPD5118_REG_TEMP		0x31	/* MR49:MR50 */
47 #define SPD5118_REG_TEMP_STATUS		0x33	/* MR51 */
48 
49 #define SPD5118_TEMP_STATUS_HIGH	BIT(0)
50 #define SPD5118_TEMP_STATUS_LOW		BIT(1)
51 #define SPD5118_TEMP_STATUS_CRIT	BIT(2)
52 #define SPD5118_TEMP_STATUS_LCRIT	BIT(3)
53 
54 #define SPD5118_CAP_TS_SUPPORT		BIT(1)	/* temperature sensor support */
55 
56 #define SPD5118_TS_DISABLE		BIT(0)	/* temperature sensor disable */
57 
58 #define SPD5118_LEGACY_MODE_ADDR	BIT(3)
59 #define SPD5118_LEGACY_PAGE_MASK	GENMASK(2, 0)
60 #define SPD5118_LEGACY_MODE_MASK	(SPD5118_LEGACY_MODE_ADDR | SPD5118_LEGACY_PAGE_MASK)
61 
62 #define SPD5118_NUM_PAGES		8
63 #define SPD5118_PAGE_SIZE		128
64 #define SPD5118_PAGE_SHIFT		7
65 #define SPD5118_PAGE_MASK		GENMASK(6, 0)
66 #define SPD5118_EEPROM_BASE		0x80
67 #define SPD5118_EEPROM_SIZE		(SPD5118_PAGE_SIZE * SPD5118_NUM_PAGES)
68 
69 /* Temperature unit in millicelsius */
70 #define SPD5118_TEMP_UNIT		(MILLIDEGREE_PER_DEGREE / 4)
71 /* Representable temperature range in millicelsius */
72 #define SPD5118_TEMP_RANGE_MIN		-256000
73 #define SPD5118_TEMP_RANGE_MAX		255750
74 
75 struct spd5118_data {
76 	struct regmap *regmap;
77 	struct mutex nvmem_lock;
78 };
79 
80 /* hwmon */
81 
82 static int spd5118_temp_from_reg(u16 reg)
83 {
84 	int temp = sign_extend32(reg >> 2, 10);
85 
86 	return temp * SPD5118_TEMP_UNIT;
87 }
88 
89 static u16 spd5118_temp_to_reg(long temp)
90 {
91 	temp = clamp_val(temp, SPD5118_TEMP_RANGE_MIN, SPD5118_TEMP_RANGE_MAX);
92 	return (DIV_ROUND_CLOSEST(temp, SPD5118_TEMP_UNIT) & 0x7ff) << 2;
93 }
94 
95 static int spd5118_read_temp(struct regmap *regmap, u32 attr, long *val)
96 {
97 	int reg, err;
98 	u8 regval[2];
99 	u16 temp;
100 
101 	switch (attr) {
102 	case hwmon_temp_input:
103 		reg = SPD5118_REG_TEMP;
104 		break;
105 	case hwmon_temp_max:
106 		reg = SPD5118_REG_TEMP_MAX;
107 		break;
108 	case hwmon_temp_min:
109 		reg = SPD5118_REG_TEMP_MIN;
110 		break;
111 	case hwmon_temp_crit:
112 		reg = SPD5118_REG_TEMP_CRIT;
113 		break;
114 	case hwmon_temp_lcrit:
115 		reg = SPD5118_REG_TEMP_LCRIT;
116 		break;
117 	default:
118 		return -EOPNOTSUPP;
119 	}
120 
121 	err = regmap_bulk_read(regmap, reg, regval, 2);
122 	if (err)
123 		return err;
124 
125 	temp = (regval[1] << 8) | regval[0];
126 
127 	*val = spd5118_temp_from_reg(temp);
128 	return 0;
129 }
130 
131 static int spd5118_read_alarm(struct regmap *regmap, u32 attr, long *val)
132 {
133 	unsigned int mask, regval;
134 	int err;
135 
136 	switch (attr) {
137 	case hwmon_temp_max_alarm:
138 		mask = SPD5118_TEMP_STATUS_HIGH;
139 		break;
140 	case hwmon_temp_min_alarm:
141 		mask = SPD5118_TEMP_STATUS_LOW;
142 		break;
143 	case hwmon_temp_crit_alarm:
144 		mask = SPD5118_TEMP_STATUS_CRIT;
145 		break;
146 	case hwmon_temp_lcrit_alarm:
147 		mask = SPD5118_TEMP_STATUS_LCRIT;
148 		break;
149 	default:
150 		return -EOPNOTSUPP;
151 	}
152 
153 	err = regmap_read(regmap, SPD5118_REG_TEMP_STATUS, &regval);
154 	if (err < 0)
155 		return err;
156 	*val = !!(regval & mask);
157 	if (*val)
158 		return regmap_write(regmap, SPD5118_REG_TEMP_CLR, mask);
159 	return 0;
160 }
161 
162 static int spd5118_read_enable(struct regmap *regmap, long *val)
163 {
164 	u32 regval;
165 	int err;
166 
167 	err = regmap_read(regmap, SPD5118_REG_TEMP_CONFIG, &regval);
168 	if (err < 0)
169 		return err;
170 	*val = !(regval & SPD5118_TS_DISABLE);
171 	return 0;
172 }
173 
174 static int spd5118_read(struct device *dev, enum hwmon_sensor_types type,
175 			u32 attr, int channel, long *val)
176 {
177 	struct regmap *regmap = dev_get_drvdata(dev);
178 
179 	if (type != hwmon_temp)
180 		return -EOPNOTSUPP;
181 
182 	switch (attr) {
183 	case hwmon_temp_input:
184 	case hwmon_temp_max:
185 	case hwmon_temp_min:
186 	case hwmon_temp_crit:
187 	case hwmon_temp_lcrit:
188 		return spd5118_read_temp(regmap, attr, val);
189 	case hwmon_temp_max_alarm:
190 	case hwmon_temp_min_alarm:
191 	case hwmon_temp_crit_alarm:
192 	case hwmon_temp_lcrit_alarm:
193 		return spd5118_read_alarm(regmap, attr, val);
194 	case hwmon_temp_enable:
195 		return spd5118_read_enable(regmap, val);
196 	default:
197 		return -EOPNOTSUPP;
198 	}
199 }
200 
201 static int spd5118_write_temp(struct regmap *regmap, u32 attr, long val)
202 {
203 	u8 regval[2];
204 	u16 temp;
205 	int reg;
206 
207 	switch (attr) {
208 	case hwmon_temp_max:
209 		reg = SPD5118_REG_TEMP_MAX;
210 		break;
211 	case hwmon_temp_min:
212 		reg = SPD5118_REG_TEMP_MIN;
213 		break;
214 	case hwmon_temp_crit:
215 		reg = SPD5118_REG_TEMP_CRIT;
216 		break;
217 	case hwmon_temp_lcrit:
218 		reg = SPD5118_REG_TEMP_LCRIT;
219 		break;
220 	default:
221 		return -EOPNOTSUPP;
222 	}
223 
224 	temp = spd5118_temp_to_reg(val);
225 	regval[0] = temp & 0xff;
226 	regval[1] = temp >> 8;
227 
228 	return regmap_bulk_write(regmap, reg, regval, 2);
229 }
230 
231 static int spd5118_write_enable(struct regmap *regmap, long val)
232 {
233 	if (val && val != 1)
234 		return -EINVAL;
235 
236 	return regmap_update_bits(regmap, SPD5118_REG_TEMP_CONFIG,
237 				  SPD5118_TS_DISABLE,
238 				  val ? 0 : SPD5118_TS_DISABLE);
239 }
240 
241 static int spd5118_temp_write(struct regmap *regmap, u32 attr, long val)
242 {
243 	switch (attr) {
244 	case hwmon_temp_max:
245 	case hwmon_temp_min:
246 	case hwmon_temp_crit:
247 	case hwmon_temp_lcrit:
248 		return spd5118_write_temp(regmap, attr, val);
249 	case hwmon_temp_enable:
250 		return spd5118_write_enable(regmap, val);
251 	default:
252 		return -EOPNOTSUPP;
253 	}
254 }
255 
256 static int spd5118_write(struct device *dev, enum hwmon_sensor_types type,
257 			 u32 attr, int channel, long val)
258 {
259 	struct regmap *regmap = dev_get_drvdata(dev);
260 
261 	switch (type) {
262 	case hwmon_temp:
263 		return spd5118_temp_write(regmap, attr, val);
264 	default:
265 		return -EOPNOTSUPP;
266 	}
267 }
268 
269 static umode_t spd5118_is_visible(const void *_data, enum hwmon_sensor_types type,
270 				  u32 attr, int channel)
271 {
272 	if (type != hwmon_temp)
273 		return 0;
274 
275 	switch (attr) {
276 	case hwmon_temp_input:
277 		return 0444;
278 	case hwmon_temp_min:
279 	case hwmon_temp_max:
280 	case hwmon_temp_lcrit:
281 	case hwmon_temp_crit:
282 	case hwmon_temp_enable:
283 		return 0644;
284 	case hwmon_temp_min_alarm:
285 	case hwmon_temp_max_alarm:
286 	case hwmon_temp_crit_alarm:
287 	case hwmon_temp_lcrit_alarm:
288 		return 0444;
289 	default:
290 		return 0;
291 	}
292 }
293 
294 static inline bool spd5118_parity8(u8 w)
295 {
296 	w ^= w >> 4;
297 	return (0x6996 >> (w & 0xf)) & 1;
298 }
299 
300 /*
301  * Bank and vendor id are 8-bit fields with seven data bits and odd parity.
302  * Vendor IDs 0 and 0x7f are invalid.
303  * See Jedec standard JEP106BJ for details and a list of assigned vendor IDs.
304  */
305 static bool spd5118_vendor_valid(u8 bank, u8 id)
306 {
307 	if (!spd5118_parity8(bank) || !spd5118_parity8(id))
308 		return false;
309 
310 	id &= 0x7f;
311 	return id && id != 0x7f;
312 }
313 
314 /* Return 0 if detection is successful, -ENODEV otherwise */
315 static int spd5118_detect(struct i2c_client *client, struct i2c_board_info *info)
316 {
317 	struct i2c_adapter *adapter = client->adapter;
318 	int regval;
319 
320 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
321 				     I2C_FUNC_SMBUS_WORD_DATA))
322 		return -ENODEV;
323 
324 	regval = i2c_smbus_read_word_swapped(client, SPD5118_REG_TYPE);
325 	if (regval != 0x5118)
326 		return -ENODEV;
327 
328 	regval = i2c_smbus_read_word_data(client, SPD5118_REG_VENDOR);
329 	if (regval < 0 || !spd5118_vendor_valid(regval & 0xff, regval >> 8))
330 		return -ENODEV;
331 
332 	regval = i2c_smbus_read_byte_data(client, SPD5118_REG_CAPABILITY);
333 	if (regval < 0)
334 		return -ENODEV;
335 	if (!(regval & SPD5118_CAP_TS_SUPPORT) || (regval & 0xfc))
336 		return -ENODEV;
337 
338 	regval = i2c_smbus_read_byte_data(client, SPD5118_REG_TEMP_CLR);
339 	if (regval)
340 		return -ENODEV;
341 	regval = i2c_smbus_read_byte_data(client, SPD5118_REG_ERROR_CLR);
342 	if (regval)
343 		return -ENODEV;
344 
345 	regval = i2c_smbus_read_byte_data(client, SPD5118_REG_REVISION);
346 	if (regval < 0 || (regval & 0xc1))
347 		return -ENODEV;
348 
349 	regval = i2c_smbus_read_byte_data(client, SPD5118_REG_TEMP_CONFIG);
350 	if (regval < 0)
351 		return -ENODEV;
352 	if (regval & ~SPD5118_TS_DISABLE)
353 		return -ENODEV;
354 
355 	strscpy(info->type, "spd5118", I2C_NAME_SIZE);
356 	return 0;
357 }
358 
359 static const struct hwmon_channel_info *spd5118_info[] = {
360 	HWMON_CHANNEL_INFO(chip,
361 			   HWMON_C_REGISTER_TZ),
362 	HWMON_CHANNEL_INFO(temp,
363 			   HWMON_T_INPUT |
364 			   HWMON_T_LCRIT | HWMON_T_LCRIT_ALARM |
365 			   HWMON_T_MIN | HWMON_T_MIN_ALARM |
366 			   HWMON_T_MAX | HWMON_T_MAX_ALARM |
367 			   HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
368 			   HWMON_T_ENABLE),
369 	NULL
370 };
371 
372 static const struct hwmon_ops spd5118_hwmon_ops = {
373 	.is_visible = spd5118_is_visible,
374 	.read = spd5118_read,
375 	.write = spd5118_write,
376 };
377 
378 static const struct hwmon_chip_info spd5118_chip_info = {
379 	.ops = &spd5118_hwmon_ops,
380 	.info = spd5118_info,
381 };
382 
383 /* nvmem */
384 
385 static ssize_t spd5118_nvmem_read_page(struct regmap *regmap, char *buf,
386 				       unsigned int offset, size_t count)
387 {
388 	int addr = (offset >> SPD5118_PAGE_SHIFT) * 0x100 + SPD5118_EEPROM_BASE;
389 	int err;
390 
391 	offset &= SPD5118_PAGE_MASK;
392 
393 	/* Can't cross page boundaries */
394 	if (offset + count > SPD5118_PAGE_SIZE)
395 		count = SPD5118_PAGE_SIZE - offset;
396 
397 	err = regmap_bulk_read(regmap, addr + offset, buf, count);
398 	if (err)
399 		return err;
400 
401 	return count;
402 }
403 
404 static int spd5118_nvmem_read(void *priv, unsigned int off, void *val, size_t count)
405 {
406 	struct spd5118_data *data = priv;
407 	char *buf = val;
408 	int ret;
409 
410 	if (unlikely(!count))
411 		return count;
412 
413 	if (off + count > SPD5118_EEPROM_SIZE)
414 		return -EINVAL;
415 
416 	mutex_lock(&data->nvmem_lock);
417 
418 	while (count) {
419 		ret = spd5118_nvmem_read_page(data->regmap, buf, off, count);
420 		if (ret < 0) {
421 			mutex_unlock(&data->nvmem_lock);
422 			return ret;
423 		}
424 		buf += ret;
425 		off += ret;
426 		count -= ret;
427 	}
428 	mutex_unlock(&data->nvmem_lock);
429 	return 0;
430 }
431 
432 static int spd5118_nvmem_init(struct device *dev, struct spd5118_data *data)
433 {
434 	struct nvmem_config nvmem_config = {
435 		.type = NVMEM_TYPE_EEPROM,
436 		.name = dev_name(dev),
437 		.id = NVMEM_DEVID_NONE,
438 		.dev = dev,
439 		.base_dev = dev,
440 		.read_only = true,
441 		.root_only = false,
442 		.owner = THIS_MODULE,
443 		.compat = true,
444 		.reg_read = spd5118_nvmem_read,
445 		.priv = data,
446 		.stride = 1,
447 		.word_size = 1,
448 		.size = SPD5118_EEPROM_SIZE,
449 	};
450 	struct nvmem_device *nvmem;
451 
452 	nvmem = devm_nvmem_register(dev, &nvmem_config);
453 	return PTR_ERR_OR_ZERO(nvmem);
454 }
455 
456 /* regmap */
457 
458 static bool spd5118_writeable_reg(struct device *dev, unsigned int reg)
459 {
460 	switch (reg) {
461 	case SPD5118_REG_I2C_LEGACY_MODE:
462 	case SPD5118_REG_TEMP_CLR:
463 	case SPD5118_REG_TEMP_CONFIG:
464 	case SPD5118_REG_TEMP_MAX:
465 	case SPD5118_REG_TEMP_MAX + 1:
466 	case SPD5118_REG_TEMP_MIN:
467 	case SPD5118_REG_TEMP_MIN + 1:
468 	case SPD5118_REG_TEMP_CRIT:
469 	case SPD5118_REG_TEMP_CRIT + 1:
470 	case SPD5118_REG_TEMP_LCRIT:
471 	case SPD5118_REG_TEMP_LCRIT + 1:
472 		return true;
473 	default:
474 		return false;
475 	}
476 }
477 
478 static bool spd5118_volatile_reg(struct device *dev, unsigned int reg)
479 {
480 	switch (reg) {
481 	case SPD5118_REG_TEMP_CLR:
482 	case SPD5118_REG_ERROR_CLR:
483 	case SPD5118_REG_TEMP:
484 	case SPD5118_REG_TEMP + 1:
485 	case SPD5118_REG_TEMP_STATUS:
486 		return true;
487 	default:
488 		return false;
489 	}
490 }
491 
492 static const struct regmap_range_cfg spd5118_regmap_range_cfg[] = {
493 	{
494 	.selector_reg   = SPD5118_REG_I2C_LEGACY_MODE,
495 	.selector_mask  = SPD5118_LEGACY_PAGE_MASK,
496 	.selector_shift = 0,
497 	.window_start   = 0,
498 	.window_len     = 0x100,
499 	.range_min      = 0,
500 	.range_max      = 0x7ff,
501 	},
502 };
503 
504 static const struct regmap_config spd5118_regmap_config = {
505 	.reg_bits = 8,
506 	.val_bits = 8,
507 	.max_register = 0x7ff,
508 	.writeable_reg = spd5118_writeable_reg,
509 	.volatile_reg = spd5118_volatile_reg,
510 	.cache_type = REGCACHE_MAPLE,
511 
512 	.ranges = spd5118_regmap_range_cfg,
513 	.num_ranges = ARRAY_SIZE(spd5118_regmap_range_cfg),
514 };
515 
516 static int spd5118_init(struct i2c_client *client)
517 {
518 	struct i2c_adapter *adapter = client->adapter;
519 	int err, regval, mode;
520 
521 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
522 				     I2C_FUNC_SMBUS_WORD_DATA))
523 		return -ENODEV;
524 
525 	regval = i2c_smbus_read_word_swapped(client, SPD5118_REG_TYPE);
526 	if (regval < 0 || (regval && regval != 0x5118))
527 		return -ENODEV;
528 
529 	/*
530 	 * If the device type registers return 0, it is possible that the chip
531 	 * has a non-zero page selected and takes the specification literally,
532 	 * i.e. disables access to volatile registers besides the page register
533 	 * if the page is not 0. Try to identify such chips.
534 	 */
535 	if (!regval) {
536 		/* Vendor ID registers must also be 0 */
537 		regval = i2c_smbus_read_word_data(client, SPD5118_REG_VENDOR);
538 		if (regval)
539 			return -ENODEV;
540 
541 		/* The selected page in MR11 must not be 0 */
542 		mode = i2c_smbus_read_byte_data(client, SPD5118_REG_I2C_LEGACY_MODE);
543 		if (mode < 0 || (mode & ~SPD5118_LEGACY_MODE_MASK) ||
544 		    !(mode & SPD5118_LEGACY_PAGE_MASK))
545 			return -ENODEV;
546 
547 		err = i2c_smbus_write_byte_data(client, SPD5118_REG_I2C_LEGACY_MODE,
548 						mode & SPD5118_LEGACY_MODE_ADDR);
549 		if (err)
550 			return -ENODEV;
551 
552 		/*
553 		 * If the device type registers are still bad after selecting
554 		 * page 0, this is not a SPD5118 device. Restore original
555 		 * legacy mode register value and abort.
556 		 */
557 		regval = i2c_smbus_read_word_swapped(client, SPD5118_REG_TYPE);
558 		if (regval != 0x5118) {
559 			i2c_smbus_write_byte_data(client, SPD5118_REG_I2C_LEGACY_MODE, mode);
560 			return -ENODEV;
561 		}
562 	}
563 
564 	/* We are reasonably sure that this is really a SPD5118 hub controller */
565 	return 0;
566 }
567 
568 static int spd5118_probe(struct i2c_client *client)
569 {
570 	struct device *dev = &client->dev;
571 	unsigned int regval, revision, vendor, bank;
572 	struct spd5118_data *data;
573 	struct device *hwmon_dev;
574 	struct regmap *regmap;
575 	int err;
576 
577 	err = spd5118_init(client);
578 	if (err)
579 		return err;
580 
581 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
582 	if (!data)
583 		return -ENOMEM;
584 
585 	regmap = devm_regmap_init_i2c(client, &spd5118_regmap_config);
586 	if (IS_ERR(regmap))
587 		return dev_err_probe(dev, PTR_ERR(regmap), "regmap init failed\n");
588 
589 	err = regmap_read(regmap, SPD5118_REG_CAPABILITY, &regval);
590 	if (err)
591 		return err;
592 	if (!(regval & SPD5118_CAP_TS_SUPPORT))
593 		return -ENODEV;
594 
595 	err = regmap_read(regmap, SPD5118_REG_REVISION, &revision);
596 	if (err)
597 		return err;
598 
599 	err = regmap_read(regmap, SPD5118_REG_VENDOR, &bank);
600 	if (err)
601 		return err;
602 	err = regmap_read(regmap, SPD5118_REG_VENDOR + 1, &vendor);
603 	if (err)
604 		return err;
605 	if (!spd5118_vendor_valid(bank, vendor))
606 		return -ENODEV;
607 
608 	data->regmap = regmap;
609 	mutex_init(&data->nvmem_lock);
610 	dev_set_drvdata(dev, data);
611 
612 	err = spd5118_nvmem_init(dev, data);
613 	/* Ignore if NVMEM support is disabled */
614 	if (err && err != -EOPNOTSUPP) {
615 		dev_err_probe(dev, err, "failed to register nvmem\n");
616 		return err;
617 	}
618 
619 	hwmon_dev = devm_hwmon_device_register_with_info(dev, "spd5118",
620 							 regmap, &spd5118_chip_info,
621 							 NULL);
622 	if (IS_ERR(hwmon_dev))
623 		return PTR_ERR(hwmon_dev);
624 
625 	/*
626 	 * From JESD300-5B
627 	 *   MR2 bits [5:4]: Major revision, 1..4
628 	 *   MR2 bits [3:1]: Minor revision, 0..8? Probably a typo, assume 1..8
629 	 */
630 	dev_info(dev, "DDR5 temperature sensor: vendor 0x%02x:0x%02x revision %d.%d\n",
631 		 bank & 0x7f, vendor, ((revision >> 4) & 0x03) + 1, ((revision >> 1) & 0x07) + 1);
632 
633 	return 0;
634 }
635 
636 static int spd5118_suspend(struct device *dev)
637 {
638 	struct spd5118_data *data = dev_get_drvdata(dev);
639 	struct regmap *regmap = data->regmap;
640 	u32 regval;
641 	int err;
642 
643 	/*
644 	 * Make sure the configuration register in the regmap cache is current
645 	 * before bypassing it.
646 	 */
647 	err = regmap_read(regmap, SPD5118_REG_TEMP_CONFIG, &regval);
648 	if (err < 0)
649 		return err;
650 
651 	regcache_cache_bypass(regmap, true);
652 	regmap_update_bits(regmap, SPD5118_REG_TEMP_CONFIG, SPD5118_TS_DISABLE,
653 			   SPD5118_TS_DISABLE);
654 	regcache_cache_bypass(regmap, false);
655 
656 	regcache_cache_only(regmap, true);
657 	regcache_mark_dirty(regmap);
658 
659 	return 0;
660 }
661 
662 static int spd5118_resume(struct device *dev)
663 {
664 	struct spd5118_data *data = dev_get_drvdata(dev);
665 	struct regmap *regmap = data->regmap;
666 
667 	regcache_cache_only(regmap, false);
668 	return regcache_sync(regmap);
669 }
670 
671 static DEFINE_SIMPLE_DEV_PM_OPS(spd5118_pm_ops, spd5118_suspend, spd5118_resume);
672 
673 static const struct i2c_device_id spd5118_id[] = {
674 	{ "spd5118", 0 },
675 	{ }
676 };
677 MODULE_DEVICE_TABLE(i2c, spd5118_id);
678 
679 static const struct of_device_id spd5118_of_ids[] = {
680 	{ .compatible = "jedec,spd5118", },
681 	{ }
682 };
683 MODULE_DEVICE_TABLE(of, spd5118_of_ids);
684 
685 static struct i2c_driver spd5118_driver = {
686 	.class		= I2C_CLASS_HWMON,
687 	.driver = {
688 		.name	= "spd5118",
689 		.of_match_table = spd5118_of_ids,
690 		.pm = pm_sleep_ptr(&spd5118_pm_ops),
691 	},
692 	.probe		= spd5118_probe,
693 	.id_table	= spd5118_id,
694 	.detect		= IS_ENABLED(CONFIG_SENSORS_SPD5118_DETECT) ? spd5118_detect : NULL,
695 	.address_list	= IS_ENABLED(CONFIG_SENSORS_SPD5118_DETECT) ? normal_i2c : NULL,
696 };
697 
698 module_i2c_driver(spd5118_driver);
699 
700 MODULE_AUTHOR("René Rebe <rene@exactcode.de>");
701 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
702 MODULE_DESCRIPTION("SPD 5118 driver");
703 MODULE_LICENSE("GPL");
704