1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Hardware monitoring driver for LTC2978 and compatible chips.
4 *
5 * Copyright (c) 2011 Ericsson AB.
6 * Copyright (c) 2013, 2014, 2015 Guenter Roeck
7 * Copyright (c) 2015 Linear Technology
8 * Copyright (c) 2018 Analog Devices Inc.
9 */
10
11#include <linux/delay.h>
12#include <linux/jiffies.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/err.h>
17#include <linux/slab.h>
18#include <linux/i2c.h>
19#include <linux/regulator/driver.h>
20#include "pmbus.h"
21
22enum chips {
23	/* Managers */
24	ltc2972, ltc2974, ltc2975, ltc2977, ltc2978, ltc2979, ltc2980,
25	/* Controllers */
26	ltc3880, ltc3882, ltc3883, ltc3884, ltc3886, ltc3887, ltc3889, ltc7880,
27	/* Modules */
28	ltm2987, ltm4664, ltm4675, ltm4676, ltm4677, ltm4678, ltm4680, ltm4686,
29	ltm4700,
30};
31
32/* Common for all chips */
33#define LTC2978_MFR_VOUT_PEAK		0xdd
34#define LTC2978_MFR_VIN_PEAK		0xde
35#define LTC2978_MFR_TEMPERATURE_PEAK	0xdf
36#define LTC2978_MFR_SPECIAL_ID		0xe7	/* Undocumented on LTC3882 */
37#define LTC2978_MFR_COMMON		0xef
38
39/* LTC2974, LTC2975, LCT2977, LTC2980, LTC2978, and LTM2987 */
40#define LTC2978_MFR_VOUT_MIN		0xfb
41#define LTC2978_MFR_VIN_MIN		0xfc
42#define LTC2978_MFR_TEMPERATURE_MIN	0xfd
43
44/* LTC2974, LTC2975 */
45#define LTC2974_MFR_IOUT_PEAK		0xd7
46#define LTC2974_MFR_IOUT_MIN		0xd8
47
48/* LTC3880, LTC3882, LTC3883, LTC3887, LTM4675, and LTM4676 */
49#define LTC3880_MFR_IOUT_PEAK		0xd7
50#define LTC3880_MFR_CLEAR_PEAKS		0xe3
51#define LTC3880_MFR_TEMPERATURE2_PEAK	0xf4
52
53/* LTC3883, LTC3884, LTC3886, LTC3889 and LTC7880 only */
54#define LTC3883_MFR_IIN_PEAK		0xe1
55
56
57/* LTC2975 only */
58#define LTC2975_MFR_IIN_PEAK		0xc4
59#define LTC2975_MFR_IIN_MIN		0xc5
60#define LTC2975_MFR_PIN_PEAK		0xc6
61#define LTC2975_MFR_PIN_MIN		0xc7
62
63#define LTC2978_ID_MASK			0xfff0
64
65#define LTC2972_ID			0x0310
66#define LTC2974_ID			0x0210
67#define LTC2975_ID			0x0220
68#define LTC2977_ID			0x0130
69#define LTC2978_ID_REV1			0x0110	/* Early revision */
70#define LTC2978_ID_REV2			0x0120
71#define LTC2979_ID_A			0x8060
72#define LTC2979_ID_B			0x8070
73#define LTC2980_ID_A			0x8030	/* A/B for two die IDs */
74#define LTC2980_ID_B			0x8040
75#define LTC3880_ID			0x4020
76#define LTC3882_ID			0x4200
77#define LTC3882_ID_D1			0x4240	/* Dash 1 */
78#define LTC3883_ID			0x4300
79#define LTC3884_ID			0x4C00
80#define LTC3886_ID			0x4600
81#define LTC3887_ID			0x4700
82#define LTM2987_ID_A			0x8010	/* A/B for two die IDs */
83#define LTM2987_ID_B			0x8020
84#define LTC3889_ID			0x4900
85#define LTC7880_ID			0x49E0
86#define LTM4664_ID			0x4120
87#define LTM4675_ID			0x47a0
88#define LTM4676_ID_REV1			0x4400
89#define LTM4676_ID_REV2			0x4480
90#define LTM4676A_ID			0x47e0
91#define LTM4677_ID_REV1			0x47B0
92#define LTM4677_ID_REV2			0x47D0
93#define LTM4678_ID_REV1			0x4100
94#define LTM4678_ID_REV2			0x4110
95#define LTM4680_ID			0x4140
96#define LTM4686_ID			0x4770
97#define LTM4700_ID			0x4130
98
99#define LTC2972_NUM_PAGES		2
100#define LTC2974_NUM_PAGES		4
101#define LTC2978_NUM_PAGES		8
102#define LTC3880_NUM_PAGES		2
103#define LTC3883_NUM_PAGES		1
104
105#define LTC_POLL_TIMEOUT		100	/* in milli-seconds */
106
107#define LTC_NOT_BUSY			BIT(6)
108#define LTC_NOT_PENDING			BIT(5)
109
110/*
111 * LTC2978 clears peak data whenever the CLEAR_FAULTS command is executed, which
112 * happens pretty much each time chip data is updated. Raw peak data therefore
113 * does not provide much value. To be able to provide useful peak data, keep an
114 * internal cache of measured peak data, which is only cleared if an explicit
115 * "clear peak" command is executed for the sensor in question.
116 */
117
118struct ltc2978_data {
119	enum chips id;
120	u16 vin_min, vin_max;
121	u16 temp_min[LTC2974_NUM_PAGES], temp_max[LTC2974_NUM_PAGES];
122	u16 vout_min[LTC2978_NUM_PAGES], vout_max[LTC2978_NUM_PAGES];
123	u16 iout_min[LTC2974_NUM_PAGES], iout_max[LTC2974_NUM_PAGES];
124	u16 iin_min, iin_max;
125	u16 pin_min, pin_max;
126	u16 temp2_max;
127	struct pmbus_driver_info info;
128	u32 features;
129};
130#define to_ltc2978_data(x)  container_of(x, struct ltc2978_data, info)
131
132#define FEAT_CLEAR_PEAKS	BIT(0)
133#define FEAT_NEEDS_POLLING	BIT(1)
134
135#define has_clear_peaks(d)	((d)->features & FEAT_CLEAR_PEAKS)
136#define needs_polling(d)	((d)->features & FEAT_NEEDS_POLLING)
137
138static int ltc_wait_ready(struct i2c_client *client)
139{
140	unsigned long timeout = jiffies + msecs_to_jiffies(LTC_POLL_TIMEOUT);
141	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
142	struct ltc2978_data *data = to_ltc2978_data(info);
143	int status;
144	u8 mask;
145
146	if (!needs_polling(data))
147		return 0;
148
149	/*
150	 * LTC3883 does not support LTC_NOT_PENDING, even though
151	 * the datasheet claims that it does.
152	 */
153	mask = LTC_NOT_BUSY;
154	if (data->id != ltc3883)
155		mask |= LTC_NOT_PENDING;
156
157	do {
158		status = pmbus_read_byte_data(client, 0, LTC2978_MFR_COMMON);
159		if (status == -EBADMSG || status == -ENXIO) {
160			/* PEC error or NACK: chip may be busy, try again */
161			usleep_range(50, 100);
162			continue;
163		}
164		if (status < 0)
165			return status;
166
167		if ((status & mask) == mask)
168			return 0;
169
170		usleep_range(50, 100);
171	} while (time_before(jiffies, timeout));
172
173	return -ETIMEDOUT;
174}
175
176static int ltc_read_word_data(struct i2c_client *client, int page, int phase,
177			      int reg)
178{
179	int ret;
180
181	ret = ltc_wait_ready(client);
182	if (ret < 0)
183		return ret;
184
185	return pmbus_read_word_data(client, page, 0xff, reg);
186}
187
188static int ltc_read_byte_data(struct i2c_client *client, int page, int reg)
189{
190	int ret;
191
192	ret = ltc_wait_ready(client);
193	if (ret < 0)
194		return ret;
195
196	return pmbus_read_byte_data(client, page, reg);
197}
198
199static int ltc_write_byte(struct i2c_client *client, int page, u8 byte)
200{
201	int ret;
202
203	ret = ltc_wait_ready(client);
204	if (ret < 0)
205		return ret;
206
207	return pmbus_write_byte(client, page, byte);
208}
209
210static inline int lin11_to_val(int data)
211{
212	s16 e = ((s16)data) >> 11;
213	s32 m = (((s16)(data << 5)) >> 5);
214
215	/*
216	 * mantissa is 10 bit + sign, exponent adds up to 15 bit.
217	 * Add 6 bit to exponent for maximum accuracy (10 + 15 + 6 = 31).
218	 */
219	e += 6;
220	return (e < 0 ? m >> -e : m << e);
221}
222
223static int ltc_get_max(struct ltc2978_data *data, struct i2c_client *client,
224		       int page, int reg, u16 *pmax)
225{
226	int ret;
227
228	ret = ltc_read_word_data(client, page, 0xff, reg);
229	if (ret >= 0) {
230		if (lin11_to_val(ret) > lin11_to_val(*pmax))
231			*pmax = ret;
232		ret = *pmax;
233	}
234	return ret;
235}
236
237static int ltc_get_min(struct ltc2978_data *data, struct i2c_client *client,
238		       int page, int reg, u16 *pmin)
239{
240	int ret;
241
242	ret = ltc_read_word_data(client, page, 0xff, reg);
243	if (ret >= 0) {
244		if (lin11_to_val(ret) < lin11_to_val(*pmin))
245			*pmin = ret;
246		ret = *pmin;
247	}
248	return ret;
249}
250
251static int ltc2978_read_word_data_common(struct i2c_client *client, int page,
252					 int reg)
253{
254	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
255	struct ltc2978_data *data = to_ltc2978_data(info);
256	int ret;
257
258	switch (reg) {
259	case PMBUS_VIRT_READ_VIN_MAX:
260		ret = ltc_get_max(data, client, page, LTC2978_MFR_VIN_PEAK,
261				  &data->vin_max);
262		break;
263	case PMBUS_VIRT_READ_VOUT_MAX:
264		ret = ltc_read_word_data(client, page, 0xff,
265					 LTC2978_MFR_VOUT_PEAK);
266		if (ret >= 0) {
267			/*
268			 * VOUT is 16 bit unsigned with fixed exponent,
269			 * so we can compare it directly
270			 */
271			if (ret > data->vout_max[page])
272				data->vout_max[page] = ret;
273			ret = data->vout_max[page];
274		}
275		break;
276	case PMBUS_VIRT_READ_TEMP_MAX:
277		ret = ltc_get_max(data, client, page,
278				  LTC2978_MFR_TEMPERATURE_PEAK,
279				  &data->temp_max[page]);
280		break;
281	case PMBUS_VIRT_RESET_VOUT_HISTORY:
282	case PMBUS_VIRT_RESET_VIN_HISTORY:
283	case PMBUS_VIRT_RESET_TEMP_HISTORY:
284		ret = 0;
285		break;
286	default:
287		ret = ltc_wait_ready(client);
288		if (ret < 0)
289			return ret;
290		ret = -ENODATA;
291		break;
292	}
293	return ret;
294}
295
296static int ltc2978_read_word_data(struct i2c_client *client, int page,
297				  int phase, int reg)
298{
299	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
300	struct ltc2978_data *data = to_ltc2978_data(info);
301	int ret;
302
303	switch (reg) {
304	case PMBUS_VIRT_READ_VIN_MIN:
305		ret = ltc_get_min(data, client, page, LTC2978_MFR_VIN_MIN,
306				  &data->vin_min);
307		break;
308	case PMBUS_VIRT_READ_VOUT_MIN:
309		ret = ltc_read_word_data(client, page, phase,
310					 LTC2978_MFR_VOUT_MIN);
311		if (ret >= 0) {
312			/*
313			 * VOUT_MIN is known to not be supported on some lots
314			 * of LTC2978 revision 1, and will return the maximum
315			 * possible voltage if read. If VOUT_MAX is valid and
316			 * lower than the reading of VOUT_MIN, use it instead.
317			 */
318			if (data->vout_max[page] && ret > data->vout_max[page])
319				ret = data->vout_max[page];
320			if (ret < data->vout_min[page])
321				data->vout_min[page] = ret;
322			ret = data->vout_min[page];
323		}
324		break;
325	case PMBUS_VIRT_READ_TEMP_MIN:
326		ret = ltc_get_min(data, client, page,
327				  LTC2978_MFR_TEMPERATURE_MIN,
328				  &data->temp_min[page]);
329		break;
330	case PMBUS_VIRT_READ_IOUT_MAX:
331	case PMBUS_VIRT_RESET_IOUT_HISTORY:
332	case PMBUS_VIRT_READ_TEMP2_MAX:
333	case PMBUS_VIRT_RESET_TEMP2_HISTORY:
334		ret = -ENXIO;
335		break;
336	default:
337		ret = ltc2978_read_word_data_common(client, page, reg);
338		break;
339	}
340	return ret;
341}
342
343static int ltc2974_read_word_data(struct i2c_client *client, int page,
344				  int phase, int reg)
345{
346	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
347	struct ltc2978_data *data = to_ltc2978_data(info);
348	int ret;
349
350	switch (reg) {
351	case PMBUS_VIRT_READ_IOUT_MAX:
352		ret = ltc_get_max(data, client, page, LTC2974_MFR_IOUT_PEAK,
353				  &data->iout_max[page]);
354		break;
355	case PMBUS_VIRT_READ_IOUT_MIN:
356		ret = ltc_get_min(data, client, page, LTC2974_MFR_IOUT_MIN,
357				  &data->iout_min[page]);
358		break;
359	case PMBUS_VIRT_RESET_IOUT_HISTORY:
360		ret = 0;
361		break;
362	default:
363		ret = ltc2978_read_word_data(client, page, phase, reg);
364		break;
365	}
366	return ret;
367}
368
369static int ltc2975_read_word_data(struct i2c_client *client, int page,
370				  int phase, int reg)
371{
372	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
373	struct ltc2978_data *data = to_ltc2978_data(info);
374	int ret;
375
376	switch (reg) {
377	case PMBUS_VIRT_READ_IIN_MAX:
378		ret = ltc_get_max(data, client, page, LTC2975_MFR_IIN_PEAK,
379				  &data->iin_max);
380		break;
381	case PMBUS_VIRT_READ_IIN_MIN:
382		ret = ltc_get_min(data, client, page, LTC2975_MFR_IIN_MIN,
383				  &data->iin_min);
384		break;
385	case PMBUS_VIRT_READ_PIN_MAX:
386		ret = ltc_get_max(data, client, page, LTC2975_MFR_PIN_PEAK,
387				  &data->pin_max);
388		break;
389	case PMBUS_VIRT_READ_PIN_MIN:
390		ret = ltc_get_min(data, client, page, LTC2975_MFR_PIN_MIN,
391				  &data->pin_min);
392		break;
393	case PMBUS_VIRT_RESET_IIN_HISTORY:
394	case PMBUS_VIRT_RESET_PIN_HISTORY:
395		ret = 0;
396		break;
397	default:
398		ret = ltc2978_read_word_data(client, page, phase, reg);
399		break;
400	}
401	return ret;
402}
403
404static int ltc3880_read_word_data(struct i2c_client *client, int page,
405				  int phase, int reg)
406{
407	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
408	struct ltc2978_data *data = to_ltc2978_data(info);
409	int ret;
410
411	switch (reg) {
412	case PMBUS_VIRT_READ_IOUT_MAX:
413		ret = ltc_get_max(data, client, page, LTC3880_MFR_IOUT_PEAK,
414				  &data->iout_max[page]);
415		break;
416	case PMBUS_VIRT_READ_TEMP2_MAX:
417		ret = ltc_get_max(data, client, page,
418				  LTC3880_MFR_TEMPERATURE2_PEAK,
419				  &data->temp2_max);
420		break;
421	case PMBUS_VIRT_READ_VIN_MIN:
422	case PMBUS_VIRT_READ_VOUT_MIN:
423	case PMBUS_VIRT_READ_TEMP_MIN:
424		ret = -ENXIO;
425		break;
426	case PMBUS_VIRT_RESET_IOUT_HISTORY:
427	case PMBUS_VIRT_RESET_TEMP2_HISTORY:
428		ret = 0;
429		break;
430	default:
431		ret = ltc2978_read_word_data_common(client, page, reg);
432		break;
433	}
434	return ret;
435}
436
437static int ltc3883_read_word_data(struct i2c_client *client, int page,
438				  int phase, int reg)
439{
440	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
441	struct ltc2978_data *data = to_ltc2978_data(info);
442	int ret;
443
444	switch (reg) {
445	case PMBUS_VIRT_READ_IIN_MAX:
446		ret = ltc_get_max(data, client, page, LTC3883_MFR_IIN_PEAK,
447				  &data->iin_max);
448		break;
449	case PMBUS_VIRT_RESET_IIN_HISTORY:
450		ret = 0;
451		break;
452	default:
453		ret = ltc3880_read_word_data(client, page, phase, reg);
454		break;
455	}
456	return ret;
457}
458
459static int ltc2978_clear_peaks(struct ltc2978_data *data,
460			       struct i2c_client *client, int page)
461{
462	int ret;
463
464	if (has_clear_peaks(data))
465		ret = ltc_write_byte(client, 0, LTC3880_MFR_CLEAR_PEAKS);
466	else
467		ret = ltc_write_byte(client, page, PMBUS_CLEAR_FAULTS);
468
469	return ret;
470}
471
472static int ltc2978_write_word_data(struct i2c_client *client, int page,
473				    int reg, u16 word)
474{
475	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
476	struct ltc2978_data *data = to_ltc2978_data(info);
477	int ret;
478
479	switch (reg) {
480	case PMBUS_VIRT_RESET_IIN_HISTORY:
481		data->iin_max = 0x7c00;
482		data->iin_min = 0x7bff;
483		ret = ltc2978_clear_peaks(data, client, 0);
484		break;
485	case PMBUS_VIRT_RESET_PIN_HISTORY:
486		data->pin_max = 0x7c00;
487		data->pin_min = 0x7bff;
488		ret = ltc2978_clear_peaks(data, client, 0);
489		break;
490	case PMBUS_VIRT_RESET_IOUT_HISTORY:
491		data->iout_max[page] = 0x7c00;
492		data->iout_min[page] = 0xfbff;
493		ret = ltc2978_clear_peaks(data, client, page);
494		break;
495	case PMBUS_VIRT_RESET_TEMP2_HISTORY:
496		data->temp2_max = 0x7c00;
497		ret = ltc2978_clear_peaks(data, client, page);
498		break;
499	case PMBUS_VIRT_RESET_VOUT_HISTORY:
500		data->vout_min[page] = 0xffff;
501		data->vout_max[page] = 0;
502		ret = ltc2978_clear_peaks(data, client, page);
503		break;
504	case PMBUS_VIRT_RESET_VIN_HISTORY:
505		data->vin_min = 0x7bff;
506		data->vin_max = 0x7c00;
507		ret = ltc2978_clear_peaks(data, client, page);
508		break;
509	case PMBUS_VIRT_RESET_TEMP_HISTORY:
510		data->temp_min[page] = 0x7bff;
511		data->temp_max[page] = 0x7c00;
512		ret = ltc2978_clear_peaks(data, client, page);
513		break;
514	default:
515		ret = ltc_wait_ready(client);
516		if (ret < 0)
517			return ret;
518		ret = -ENODATA;
519		break;
520	}
521	return ret;
522}
523
524static const struct i2c_device_id ltc2978_id[] = {
525	{"ltc2972", ltc2972},
526	{"ltc2974", ltc2974},
527	{"ltc2975", ltc2975},
528	{"ltc2977", ltc2977},
529	{"ltc2978", ltc2978},
530	{"ltc2979", ltc2979},
531	{"ltc2980", ltc2980},
532	{"ltc3880", ltc3880},
533	{"ltc3882", ltc3882},
534	{"ltc3883", ltc3883},
535	{"ltc3884", ltc3884},
536	{"ltc3886", ltc3886},
537	{"ltc3887", ltc3887},
538	{"ltc3889", ltc3889},
539	{"ltc7880", ltc7880},
540	{"ltm2987", ltm2987},
541	{"ltm4664", ltm4664},
542	{"ltm4675", ltm4675},
543	{"ltm4676", ltm4676},
544	{"ltm4677", ltm4677},
545	{"ltm4678", ltm4678},
546	{"ltm4680", ltm4680},
547	{"ltm4686", ltm4686},
548	{"ltm4700", ltm4700},
549	{}
550};
551MODULE_DEVICE_TABLE(i2c, ltc2978_id);
552
553#if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
554static const struct regulator_desc ltc2978_reg_desc[] = {
555	PMBUS_REGULATOR("vout", 0),
556	PMBUS_REGULATOR("vout", 1),
557	PMBUS_REGULATOR("vout", 2),
558	PMBUS_REGULATOR("vout", 3),
559	PMBUS_REGULATOR("vout", 4),
560	PMBUS_REGULATOR("vout", 5),
561	PMBUS_REGULATOR("vout", 6),
562	PMBUS_REGULATOR("vout", 7),
563};
564#endif /* CONFIG_SENSORS_LTC2978_REGULATOR */
565
566static int ltc2978_get_id(struct i2c_client *client)
567{
568	int chip_id;
569
570	chip_id = i2c_smbus_read_word_data(client, LTC2978_MFR_SPECIAL_ID);
571	if (chip_id < 0) {
572		const struct i2c_device_id *id;
573		u8 buf[I2C_SMBUS_BLOCK_MAX];
574		int ret;
575
576		if (!i2c_check_functionality(client->adapter,
577					     I2C_FUNC_SMBUS_READ_BLOCK_DATA))
578			return -ENODEV;
579
580		ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
581		if (ret < 0)
582			return ret;
583		if (ret < 3 || strncmp(buf, "LTC", 3))
584			return -ENODEV;
585
586		ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
587		if (ret < 0)
588			return ret;
589		for (id = &ltc2978_id[0]; strlen(id->name); id++) {
590			if (!strncasecmp(id->name, buf, strlen(id->name)))
591				return (int)id->driver_data;
592		}
593		return -ENODEV;
594	}
595
596	chip_id &= LTC2978_ID_MASK;
597
598	if (chip_id == LTC2972_ID)
599		return ltc2972;
600	else if (chip_id == LTC2974_ID)
601		return ltc2974;
602	else if (chip_id == LTC2975_ID)
603		return ltc2975;
604	else if (chip_id == LTC2977_ID)
605		return ltc2977;
606	else if (chip_id == LTC2978_ID_REV1 || chip_id == LTC2978_ID_REV2)
607		return ltc2978;
608	else if (chip_id == LTC2979_ID_A || chip_id == LTC2979_ID_B)
609		return ltc2979;
610	else if (chip_id == LTC2980_ID_A || chip_id == LTC2980_ID_B)
611		return ltc2980;
612	else if (chip_id == LTC3880_ID)
613		return ltc3880;
614	else if (chip_id == LTC3882_ID || chip_id == LTC3882_ID_D1)
615		return ltc3882;
616	else if (chip_id == LTC3883_ID)
617		return ltc3883;
618	else if (chip_id == LTC3884_ID)
619		return ltc3884;
620	else if (chip_id == LTC3886_ID)
621		return ltc3886;
622	else if (chip_id == LTC3887_ID)
623		return ltc3887;
624	else if (chip_id == LTC3889_ID)
625		return ltc3889;
626	else if (chip_id == LTC7880_ID)
627		return ltc7880;
628	else if (chip_id == LTM2987_ID_A || chip_id == LTM2987_ID_B)
629		return ltm2987;
630	else if (chip_id == LTM4664_ID)
631		return ltm4664;
632	else if (chip_id == LTM4675_ID)
633		return ltm4675;
634	else if (chip_id == LTM4676_ID_REV1 || chip_id == LTM4676_ID_REV2 ||
635		 chip_id == LTM4676A_ID)
636		return ltm4676;
637	else if (chip_id == LTM4677_ID_REV1 || chip_id == LTM4677_ID_REV2)
638		return ltm4677;
639	else if (chip_id == LTM4678_ID_REV1 || chip_id == LTM4678_ID_REV2)
640		return ltm4678;
641	else if (chip_id == LTM4680_ID)
642		return ltm4680;
643	else if (chip_id == LTM4686_ID)
644		return ltm4686;
645	else if (chip_id == LTM4700_ID)
646		return ltm4700;
647
648	dev_err(&client->dev, "Unsupported chip ID 0x%x\n", chip_id);
649	return -ENODEV;
650}
651
652static int ltc2978_probe(struct i2c_client *client)
653{
654	int i, chip_id;
655	struct ltc2978_data *data;
656	struct pmbus_driver_info *info;
657	const struct i2c_device_id *id;
658
659	if (!i2c_check_functionality(client->adapter,
660				     I2C_FUNC_SMBUS_READ_WORD_DATA))
661		return -ENODEV;
662
663	data = devm_kzalloc(&client->dev, sizeof(struct ltc2978_data),
664			    GFP_KERNEL);
665	if (!data)
666		return -ENOMEM;
667
668	chip_id = ltc2978_get_id(client);
669	if (chip_id < 0)
670		return chip_id;
671
672	data->id = chip_id;
673	id = i2c_match_id(ltc2978_id, client);
674	if (data->id != id->driver_data)
675		dev_warn(&client->dev,
676			 "Device mismatch: Configured %s (%d), detected %d\n",
677			 id->name,
678			 (int) id->driver_data,
679			 chip_id);
680
681	info = &data->info;
682	info->write_word_data = ltc2978_write_word_data;
683	info->write_byte = ltc_write_byte;
684	info->read_word_data = ltc_read_word_data;
685	info->read_byte_data = ltc_read_byte_data;
686
687	data->vin_min = 0x7bff;
688	data->vin_max = 0x7c00;
689	for (i = 0; i < ARRAY_SIZE(data->vout_min); i++)
690		data->vout_min[i] = 0xffff;
691	for (i = 0; i < ARRAY_SIZE(data->iout_min); i++)
692		data->iout_min[i] = 0xfbff;
693	for (i = 0; i < ARRAY_SIZE(data->iout_max); i++)
694		data->iout_max[i] = 0x7c00;
695	for (i = 0; i < ARRAY_SIZE(data->temp_min); i++)
696		data->temp_min[i] = 0x7bff;
697	for (i = 0; i < ARRAY_SIZE(data->temp_max); i++)
698		data->temp_max[i] = 0x7c00;
699	data->temp2_max = 0x7c00;
700
701	switch (data->id) {
702	case ltc2972:
703		info->read_word_data = ltc2975_read_word_data;
704		info->pages = LTC2972_NUM_PAGES;
705		info->func[0] = PMBUS_HAVE_IIN | PMBUS_HAVE_PIN
706		  | PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
707		  | PMBUS_HAVE_TEMP2;
708		for (i = 0; i < info->pages; i++) {
709			info->func[i] |= PMBUS_HAVE_VOUT
710			  | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_POUT
711			  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
712			  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
713		}
714		break;
715	case ltc2974:
716		info->read_word_data = ltc2974_read_word_data;
717		info->pages = LTC2974_NUM_PAGES;
718		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
719		  | PMBUS_HAVE_TEMP2;
720		for (i = 0; i < info->pages; i++) {
721			info->func[i] |= PMBUS_HAVE_VOUT
722			  | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_POUT
723			  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
724			  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
725		}
726		break;
727	case ltc2975:
728		info->read_word_data = ltc2975_read_word_data;
729		info->pages = LTC2974_NUM_PAGES;
730		info->func[0] = PMBUS_HAVE_IIN | PMBUS_HAVE_PIN
731		  | PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
732		  | PMBUS_HAVE_TEMP2;
733		for (i = 0; i < info->pages; i++) {
734			info->func[i] |= PMBUS_HAVE_VOUT
735			  | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_POUT
736			  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
737			  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
738		}
739		break;
740
741	case ltc2977:
742	case ltc2978:
743	case ltc2979:
744	case ltc2980:
745	case ltm2987:
746		info->read_word_data = ltc2978_read_word_data;
747		info->pages = LTC2978_NUM_PAGES;
748		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
749		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
750		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
751		for (i = 1; i < LTC2978_NUM_PAGES; i++) {
752			info->func[i] = PMBUS_HAVE_VOUT
753			  | PMBUS_HAVE_STATUS_VOUT;
754		}
755		break;
756	case ltc3880:
757	case ltc3887:
758	case ltm4675:
759	case ltm4676:
760	case ltm4677:
761	case ltm4686:
762		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
763		info->read_word_data = ltc3880_read_word_data;
764		info->pages = LTC3880_NUM_PAGES;
765		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
766		  | PMBUS_HAVE_STATUS_INPUT
767		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
768		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
769		  | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
770		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
771		info->func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
772		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
773		  | PMBUS_HAVE_POUT
774		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
775		break;
776	case ltc3882:
777		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
778		info->read_word_data = ltc3880_read_word_data;
779		info->pages = LTC3880_NUM_PAGES;
780		info->func[0] = PMBUS_HAVE_VIN
781		  | PMBUS_HAVE_STATUS_INPUT
782		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
783		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
784		  | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
785		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
786		info->func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
787		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
788		  | PMBUS_HAVE_POUT
789		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
790		break;
791	case ltc3883:
792		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
793		info->read_word_data = ltc3883_read_word_data;
794		info->pages = LTC3883_NUM_PAGES;
795		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
796		  | PMBUS_HAVE_STATUS_INPUT
797		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
798		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
799		  | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
800		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
801		break;
802	case ltc3884:
803	case ltc3886:
804	case ltc3889:
805	case ltc7880:
806	case ltm4664:
807	case ltm4678:
808	case ltm4680:
809	case ltm4700:
810		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
811		info->read_word_data = ltc3883_read_word_data;
812		info->pages = LTC3880_NUM_PAGES;
813		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
814		  | PMBUS_HAVE_STATUS_INPUT
815		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
816		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
817		  | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
818		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
819		info->func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
820		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
821		  | PMBUS_HAVE_POUT
822		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
823		break;
824	default:
825		return -ENODEV;
826	}
827
828#if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
829	info->num_regulators = info->pages;
830	info->reg_desc = ltc2978_reg_desc;
831	if (info->num_regulators > ARRAY_SIZE(ltc2978_reg_desc)) {
832		dev_err(&client->dev, "num_regulators too large!");
833		info->num_regulators = ARRAY_SIZE(ltc2978_reg_desc);
834	}
835#endif
836
837	return pmbus_do_probe(client, info);
838}
839
840
841#ifdef CONFIG_OF
842static const struct of_device_id ltc2978_of_match[] = {
843	{ .compatible = "lltc,ltc2972" },
844	{ .compatible = "lltc,ltc2974" },
845	{ .compatible = "lltc,ltc2975" },
846	{ .compatible = "lltc,ltc2977" },
847	{ .compatible = "lltc,ltc2978" },
848	{ .compatible = "lltc,ltc2979" },
849	{ .compatible = "lltc,ltc2980" },
850	{ .compatible = "lltc,ltc3880" },
851	{ .compatible = "lltc,ltc3882" },
852	{ .compatible = "lltc,ltc3883" },
853	{ .compatible = "lltc,ltc3884" },
854	{ .compatible = "lltc,ltc3886" },
855	{ .compatible = "lltc,ltc3887" },
856	{ .compatible = "lltc,ltc3889" },
857	{ .compatible = "lltc,ltc7880" },
858	{ .compatible = "lltc,ltm2987" },
859	{ .compatible = "lltc,ltm4664" },
860	{ .compatible = "lltc,ltm4675" },
861	{ .compatible = "lltc,ltm4676" },
862	{ .compatible = "lltc,ltm4677" },
863	{ .compatible = "lltc,ltm4678" },
864	{ .compatible = "lltc,ltm4680" },
865	{ .compatible = "lltc,ltm4686" },
866	{ .compatible = "lltc,ltm4700" },
867	{ }
868};
869MODULE_DEVICE_TABLE(of, ltc2978_of_match);
870#endif
871
872static struct i2c_driver ltc2978_driver = {
873	.driver = {
874		   .name = "ltc2978",
875		   .of_match_table = of_match_ptr(ltc2978_of_match),
876		   },
877	.probe_new = ltc2978_probe,
878	.remove = pmbus_do_remove,
879	.id_table = ltc2978_id,
880};
881
882module_i2c_driver(ltc2978_driver);
883
884MODULE_AUTHOR("Guenter Roeck");
885MODULE_DESCRIPTION("PMBus driver for LTC2978 and compatible chips");
886MODULE_LICENSE("GPL");
887