xref: /linux/drivers/hwmon/pmbus/ltc2978.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
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 
22 enum chips {
23 	/* Managers */
24 	ltc2972, ltc2974, ltc2975, ltc2977, ltc2978, ltc2979, ltc2980,
25 	/* Controllers */
26 	lt7170, lt7171, ltc3880, ltc3882, ltc3883, ltc3884, ltc3886, ltc3887,
27 	ltc3889, ltc7132, ltc7841, ltc7880,
28 	/* Modules */
29 	ltm2987, ltm4664, ltm4673, ltm4675, ltm4676, ltm4677, ltm4678, ltm4680,
30 	ltm4686, ltm4700,
31 };
32 
33 /* Common for all chips */
34 #define LTC2978_MFR_VOUT_PEAK		0xdd
35 #define LTC2978_MFR_VIN_PEAK		0xde
36 #define LTC2978_MFR_TEMPERATURE_PEAK	0xdf
37 #define LTC2978_MFR_SPECIAL_ID		0xe7	/* Undocumented on LTC3882 */
38 #define LTC2978_MFR_COMMON		0xef
39 
40 /* LTC2974, LTC2975, LCT2977, LTC2980, LTC2978, and LTM2987 */
41 #define LTC2978_MFR_VOUT_MIN		0xfb
42 #define LTC2978_MFR_VIN_MIN		0xfc
43 #define LTC2978_MFR_TEMPERATURE_MIN	0xfd
44 
45 /* LTC2974, LTC2975 */
46 #define LTC2974_MFR_IOUT_PEAK		0xd7
47 #define LTC2974_MFR_IOUT_MIN		0xd8
48 
49 /* LTC3880, LTC3882, LTC3883, LTC3887, LTM4675, LTM4676, LTC7132 */
50 #define LTC3880_MFR_IOUT_PEAK		0xd7
51 #define LTC3880_MFR_CLEAR_PEAKS		0xe3
52 #define LTC3880_MFR_TEMPERATURE2_PEAK	0xf4
53 
54 /* LTC3883, LTC3884, LTC3886, LTC3889, LTC7132, LTC7841 and LTC7880 only */
55 #define LTC3883_MFR_IIN_PEAK		0xe1
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 LT7170_ID			0x1C10
66 #define LTC2972_ID			0x0310
67 #define LTC2974_ID			0x0210
68 #define LTC2975_ID			0x0220
69 #define LTC2977_ID			0x0130
70 #define LTC2978_ID_REV1			0x0110	/* Early revision */
71 #define LTC2978_ID_REV2			0x0120
72 #define LTC2979_ID_A			0x8060
73 #define LTC2979_ID_B			0x8070
74 #define LTC2980_ID_A			0x8030	/* A/B for two die IDs */
75 #define LTC2980_ID_B			0x8040
76 #define LTC3880_ID			0x4020
77 #define LTC3882_ID			0x4200
78 #define LTC3882_ID_D1			0x4240	/* Dash 1 */
79 #define LTC3883_ID			0x4300
80 #define LTC3884_ID			0x4C00
81 #define LTC3886_ID			0x4600
82 #define LTC3887_ID			0x4700
83 #define LTC3889_ID			0x4900
84 #define LTC7132_ID			0x4CE0
85 #define LTC7841_ID			0x40D0
86 #define LTC7880_ID			0x49E0
87 #define LTM2987_ID_A			0x8010	/* A/B for two die IDs */
88 #define LTM2987_ID_B			0x8020
89 #define LTM4664_ID			0x4120
90 #define LTM4673_ID_REV1			0x0230
91 #define LTM4673_ID			0x4480
92 #define LTM4675_ID			0x47a0
93 #define LTM4676_ID_REV1			0x4400
94 #define LTM4676_ID_REV2			0x4480
95 #define LTM4676A_ID			0x47e0
96 #define LTM4677_ID_REV1			0x47B0
97 #define LTM4677_ID_REV2			0x47D0
98 #define LTM4678_ID_REV1			0x4100
99 #define LTM4678_ID_REV2			0x4110
100 #define LTM4680_ID			0x4140
101 #define LTM4686_ID			0x4770
102 #define LTM4700_ID			0x4130
103 
104 #define LTC2972_NUM_PAGES		2
105 #define LTC2974_NUM_PAGES		4
106 #define LTC2978_NUM_PAGES		8
107 #define LTC3880_NUM_PAGES		2
108 #define LTC3883_NUM_PAGES		1
109 
110 #define LTC_POLL_TIMEOUT		100	/* in milli-seconds */
111 
112 #define LTC_NOT_BUSY			BIT(6)
113 #define LTC_NOT_PENDING			BIT(5)
114 
115 /*
116  * LTC2978 clears peak data whenever the CLEAR_FAULTS command is executed, which
117  * happens pretty much each time chip data is updated. Raw peak data therefore
118  * does not provide much value. To be able to provide useful peak data, keep an
119  * internal cache of measured peak data, which is only cleared if an explicit
120  * "clear peak" command is executed for the sensor in question.
121  */
122 
123 struct ltc2978_data {
124 	enum chips id;
125 	u16 vin_min, vin_max;
126 	u16 temp_min[LTC2974_NUM_PAGES], temp_max[LTC2974_NUM_PAGES];
127 	u16 vout_min[LTC2978_NUM_PAGES], vout_max[LTC2978_NUM_PAGES];
128 	u16 iout_min[LTC2974_NUM_PAGES], iout_max[LTC2974_NUM_PAGES];
129 	u16 iin_min, iin_max;
130 	u16 pin_min, pin_max;
131 	u16 temp2_max;
132 	struct pmbus_driver_info info;
133 	u32 features;
134 };
135 #define to_ltc2978_data(x)  container_of(x, struct ltc2978_data, info)
136 
137 #define FEAT_CLEAR_PEAKS	BIT(0)
138 #define FEAT_NEEDS_POLLING	BIT(1)
139 
140 #define has_clear_peaks(d)	((d)->features & FEAT_CLEAR_PEAKS)
141 #define needs_polling(d)	((d)->features & FEAT_NEEDS_POLLING)
142 
143 static int ltc_wait_ready(struct i2c_client *client)
144 {
145 	unsigned long timeout = jiffies + msecs_to_jiffies(LTC_POLL_TIMEOUT);
146 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
147 	struct ltc2978_data *data = to_ltc2978_data(info);
148 	int status;
149 	u8 mask;
150 
151 	if (!needs_polling(data))
152 		return 0;
153 
154 	/*
155 	 * LTC3883 does not support LTC_NOT_PENDING, even though
156 	 * the datasheet claims that it does.
157 	 */
158 	mask = LTC_NOT_BUSY;
159 	if (data->id != ltc3883)
160 		mask |= LTC_NOT_PENDING;
161 
162 	do {
163 		status = pmbus_read_byte_data(client, 0, LTC2978_MFR_COMMON);
164 		if (status == -EBADMSG || status == -ENXIO) {
165 			/* PEC error or NACK: chip may be busy, try again */
166 			usleep_range(50, 100);
167 			continue;
168 		}
169 		if (status < 0)
170 			return status;
171 
172 		if ((status & mask) == mask)
173 			return 0;
174 
175 		usleep_range(50, 100);
176 	} while (time_before(jiffies, timeout));
177 
178 	return -ETIMEDOUT;
179 }
180 
181 static int ltc_read_word_data(struct i2c_client *client, int page, int phase,
182 			      int reg)
183 {
184 	int ret;
185 
186 	ret = ltc_wait_ready(client);
187 	if (ret < 0)
188 		return ret;
189 
190 	return pmbus_read_word_data(client, page, 0xff, reg);
191 }
192 
193 static int ltc_read_byte_data(struct i2c_client *client, int page, int reg)
194 {
195 	int ret;
196 
197 	ret = ltc_wait_ready(client);
198 	if (ret < 0)
199 		return ret;
200 
201 	return pmbus_read_byte_data(client, page, reg);
202 }
203 
204 static int ltc_write_byte_data(struct i2c_client *client, int page, int reg, u8 value)
205 {
206 	int ret;
207 
208 	ret = ltc_wait_ready(client);
209 	if (ret < 0)
210 		return ret;
211 
212 	return pmbus_write_byte_data(client, page, reg, value);
213 }
214 
215 static int ltc_write_byte(struct i2c_client *client, int page, u8 byte)
216 {
217 	int ret;
218 
219 	ret = ltc_wait_ready(client);
220 	if (ret < 0)
221 		return ret;
222 
223 	return pmbus_write_byte(client, page, byte);
224 }
225 
226 static inline int lin11_to_val(int data)
227 {
228 	s16 e = ((s16)data) >> 11;
229 	s32 m = (((s16)(data << 5)) >> 5);
230 
231 	/*
232 	 * mantissa is 10 bit + sign, exponent adds up to 15 bit.
233 	 * Add 6 bit to exponent for maximum accuracy (10 + 15 + 6 = 31).
234 	 */
235 	e += 6;
236 	return (e < 0 ? m >> -e : m << e);
237 }
238 
239 static int ltc_get_max(struct ltc2978_data *data, struct i2c_client *client,
240 		       int page, int reg, u16 *pmax)
241 {
242 	int ret;
243 
244 	ret = ltc_read_word_data(client, page, 0xff, reg);
245 	if (ret >= 0) {
246 		if (lin11_to_val(ret) > lin11_to_val(*pmax))
247 			*pmax = ret;
248 		ret = *pmax;
249 	}
250 	return ret;
251 }
252 
253 static int ltc_get_min(struct ltc2978_data *data, struct i2c_client *client,
254 		       int page, int reg, u16 *pmin)
255 {
256 	int ret;
257 
258 	ret = ltc_read_word_data(client, page, 0xff, reg);
259 	if (ret >= 0) {
260 		if (lin11_to_val(ret) < lin11_to_val(*pmin))
261 			*pmin = ret;
262 		ret = *pmin;
263 	}
264 	return ret;
265 }
266 
267 static int ltc2978_read_word_data_common(struct i2c_client *client, int page,
268 					 int reg)
269 {
270 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
271 	struct ltc2978_data *data = to_ltc2978_data(info);
272 	int ret;
273 
274 	switch (reg) {
275 	case PMBUS_VIRT_READ_VIN_MAX:
276 		ret = ltc_get_max(data, client, page, LTC2978_MFR_VIN_PEAK,
277 				  &data->vin_max);
278 		break;
279 	case PMBUS_VIRT_READ_VOUT_MAX:
280 		ret = ltc_read_word_data(client, page, 0xff,
281 					 LTC2978_MFR_VOUT_PEAK);
282 		if (ret >= 0) {
283 			/*
284 			 * VOUT is 16 bit unsigned with fixed exponent,
285 			 * so we can compare it directly
286 			 */
287 			if (ret > data->vout_max[page])
288 				data->vout_max[page] = ret;
289 			ret = data->vout_max[page];
290 		}
291 		break;
292 	case PMBUS_VIRT_READ_TEMP_MAX:
293 		ret = ltc_get_max(data, client, page,
294 				  LTC2978_MFR_TEMPERATURE_PEAK,
295 				  &data->temp_max[page]);
296 		break;
297 	case PMBUS_VIRT_RESET_VOUT_HISTORY:
298 	case PMBUS_VIRT_RESET_VIN_HISTORY:
299 	case PMBUS_VIRT_RESET_TEMP_HISTORY:
300 		ret = 0;
301 		break;
302 	default:
303 		ret = ltc_wait_ready(client);
304 		if (ret < 0)
305 			return ret;
306 		ret = -ENODATA;
307 		break;
308 	}
309 	return ret;
310 }
311 
312 static int ltc2978_read_word_data(struct i2c_client *client, int page,
313 				  int phase, int reg)
314 {
315 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
316 	struct ltc2978_data *data = to_ltc2978_data(info);
317 	int ret;
318 
319 	switch (reg) {
320 	case PMBUS_VIRT_READ_VIN_MIN:
321 		ret = ltc_get_min(data, client, page, LTC2978_MFR_VIN_MIN,
322 				  &data->vin_min);
323 		break;
324 	case PMBUS_VIRT_READ_VOUT_MIN:
325 		ret = ltc_read_word_data(client, page, phase,
326 					 LTC2978_MFR_VOUT_MIN);
327 		if (ret >= 0) {
328 			/*
329 			 * VOUT_MIN is known to not be supported on some lots
330 			 * of LTC2978 revision 1, and will return the maximum
331 			 * possible voltage if read. If VOUT_MAX is valid and
332 			 * lower than the reading of VOUT_MIN, use it instead.
333 			 */
334 			if (data->vout_max[page] && ret > data->vout_max[page])
335 				ret = data->vout_max[page];
336 			if (ret < data->vout_min[page])
337 				data->vout_min[page] = ret;
338 			ret = data->vout_min[page];
339 		}
340 		break;
341 	case PMBUS_VIRT_READ_TEMP_MIN:
342 		ret = ltc_get_min(data, client, page,
343 				  LTC2978_MFR_TEMPERATURE_MIN,
344 				  &data->temp_min[page]);
345 		break;
346 	case PMBUS_VIRT_READ_IOUT_MAX:
347 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
348 	case PMBUS_VIRT_READ_TEMP2_MAX:
349 	case PMBUS_VIRT_RESET_TEMP2_HISTORY:
350 		ret = -ENXIO;
351 		break;
352 	default:
353 		ret = ltc2978_read_word_data_common(client, page, reg);
354 		break;
355 	}
356 	return ret;
357 }
358 
359 static int ltc2974_read_word_data(struct i2c_client *client, int page,
360 				  int phase, int reg)
361 {
362 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
363 	struct ltc2978_data *data = to_ltc2978_data(info);
364 	int ret;
365 
366 	switch (reg) {
367 	case PMBUS_VIRT_READ_IOUT_MAX:
368 		ret = ltc_get_max(data, client, page, LTC2974_MFR_IOUT_PEAK,
369 				  &data->iout_max[page]);
370 		break;
371 	case PMBUS_VIRT_READ_IOUT_MIN:
372 		ret = ltc_get_min(data, client, page, LTC2974_MFR_IOUT_MIN,
373 				  &data->iout_min[page]);
374 		break;
375 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
376 		ret = 0;
377 		break;
378 	default:
379 		ret = ltc2978_read_word_data(client, page, phase, reg);
380 		break;
381 	}
382 	return ret;
383 }
384 
385 static int ltc2975_read_word_data(struct i2c_client *client, int page,
386 				  int phase, int reg)
387 {
388 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
389 	struct ltc2978_data *data = to_ltc2978_data(info);
390 	int ret;
391 
392 	switch (reg) {
393 	case PMBUS_VIRT_READ_IIN_MAX:
394 		ret = ltc_get_max(data, client, page, LTC2975_MFR_IIN_PEAK,
395 				  &data->iin_max);
396 		break;
397 	case PMBUS_VIRT_READ_IIN_MIN:
398 		ret = ltc_get_min(data, client, page, LTC2975_MFR_IIN_MIN,
399 				  &data->iin_min);
400 		break;
401 	case PMBUS_VIRT_READ_PIN_MAX:
402 		ret = ltc_get_max(data, client, page, LTC2975_MFR_PIN_PEAK,
403 				  &data->pin_max);
404 		break;
405 	case PMBUS_VIRT_READ_PIN_MIN:
406 		ret = ltc_get_min(data, client, page, LTC2975_MFR_PIN_MIN,
407 				  &data->pin_min);
408 		break;
409 	case PMBUS_VIRT_RESET_IIN_HISTORY:
410 	case PMBUS_VIRT_RESET_PIN_HISTORY:
411 		ret = 0;
412 		break;
413 	default:
414 		ret = ltc2978_read_word_data(client, page, phase, reg);
415 		break;
416 	}
417 	return ret;
418 }
419 
420 static int ltc3880_read_word_data(struct i2c_client *client, int page,
421 				  int phase, int reg)
422 {
423 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
424 	struct ltc2978_data *data = to_ltc2978_data(info);
425 	int ret;
426 
427 	switch (reg) {
428 	case PMBUS_VIRT_READ_IOUT_MAX:
429 		ret = ltc_get_max(data, client, page, LTC3880_MFR_IOUT_PEAK,
430 				  &data->iout_max[page]);
431 		break;
432 	case PMBUS_VIRT_READ_TEMP2_MAX:
433 		ret = ltc_get_max(data, client, page,
434 				  LTC3880_MFR_TEMPERATURE2_PEAK,
435 				  &data->temp2_max);
436 		break;
437 	case PMBUS_VIRT_READ_VIN_MIN:
438 	case PMBUS_VIRT_READ_VOUT_MIN:
439 	case PMBUS_VIRT_READ_TEMP_MIN:
440 		ret = -ENXIO;
441 		break;
442 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
443 	case PMBUS_VIRT_RESET_TEMP2_HISTORY:
444 		ret = 0;
445 		break;
446 	default:
447 		ret = ltc2978_read_word_data_common(client, page, reg);
448 		break;
449 	}
450 	return ret;
451 }
452 
453 static int ltc3883_read_word_data(struct i2c_client *client, int page,
454 				  int phase, int reg)
455 {
456 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
457 	struct ltc2978_data *data = to_ltc2978_data(info);
458 	int ret;
459 
460 	switch (reg) {
461 	case PMBUS_VIRT_READ_IIN_MAX:
462 		ret = ltc_get_max(data, client, page, LTC3883_MFR_IIN_PEAK,
463 				  &data->iin_max);
464 		break;
465 	case PMBUS_VIRT_RESET_IIN_HISTORY:
466 		ret = 0;
467 		break;
468 	default:
469 		ret = ltc3880_read_word_data(client, page, phase, reg);
470 		break;
471 	}
472 	return ret;
473 }
474 
475 static int ltc2978_clear_peaks(struct ltc2978_data *data,
476 			       struct i2c_client *client, int page)
477 {
478 	int ret;
479 
480 	if (has_clear_peaks(data))
481 		ret = ltc_write_byte(client, 0, LTC3880_MFR_CLEAR_PEAKS);
482 	else
483 		ret = ltc_write_byte(client, page, PMBUS_CLEAR_FAULTS);
484 
485 	return ret;
486 }
487 
488 static int ltc2978_write_word_data(struct i2c_client *client, int page,
489 				    int reg, u16 word)
490 {
491 	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
492 	struct ltc2978_data *data = to_ltc2978_data(info);
493 	int ret;
494 
495 	switch (reg) {
496 	case PMBUS_VIRT_RESET_IIN_HISTORY:
497 		data->iin_max = 0x7c00;
498 		data->iin_min = 0x7bff;
499 		ret = ltc2978_clear_peaks(data, client, 0);
500 		break;
501 	case PMBUS_VIRT_RESET_PIN_HISTORY:
502 		data->pin_max = 0x7c00;
503 		data->pin_min = 0x7bff;
504 		ret = ltc2978_clear_peaks(data, client, 0);
505 		break;
506 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
507 		data->iout_max[page] = 0x7c00;
508 		data->iout_min[page] = 0xfbff;
509 		ret = ltc2978_clear_peaks(data, client, page);
510 		break;
511 	case PMBUS_VIRT_RESET_TEMP2_HISTORY:
512 		data->temp2_max = 0x7c00;
513 		ret = ltc2978_clear_peaks(data, client, page);
514 		break;
515 	case PMBUS_VIRT_RESET_VOUT_HISTORY:
516 		data->vout_min[page] = 0xffff;
517 		data->vout_max[page] = 0;
518 		ret = ltc2978_clear_peaks(data, client, page);
519 		break;
520 	case PMBUS_VIRT_RESET_VIN_HISTORY:
521 		data->vin_min = 0x7bff;
522 		data->vin_max = 0x7c00;
523 		ret = ltc2978_clear_peaks(data, client, page);
524 		break;
525 	case PMBUS_VIRT_RESET_TEMP_HISTORY:
526 		data->temp_min[page] = 0x7bff;
527 		data->temp_max[page] = 0x7c00;
528 		ret = ltc2978_clear_peaks(data, client, page);
529 		break;
530 	default:
531 		ret = ltc_wait_ready(client);
532 		if (ret < 0)
533 			return ret;
534 		ret = -ENODATA;
535 		break;
536 	}
537 	return ret;
538 }
539 
540 static const struct i2c_device_id ltc2978_id[] = {
541 	{ .name = "lt7170", .driver_data = lt7170 },
542 	{ .name = "lt7171", .driver_data = lt7171 },
543 	{ .name = "ltc2972", .driver_data = ltc2972 },
544 	{ .name = "ltc2974", .driver_data = ltc2974 },
545 	{ .name = "ltc2975", .driver_data = ltc2975 },
546 	{ .name = "ltc2977", .driver_data = ltc2977 },
547 	{ .name = "ltc2978", .driver_data = ltc2978 },
548 	{ .name = "ltc2979", .driver_data = ltc2979 },
549 	{ .name = "ltc2980", .driver_data = ltc2980 },
550 	{ .name = "ltc3880", .driver_data = ltc3880 },
551 	{ .name = "ltc3882", .driver_data = ltc3882 },
552 	{ .name = "ltc3883", .driver_data = ltc3883 },
553 	{ .name = "ltc3884", .driver_data = ltc3884 },
554 	{ .name = "ltc3886", .driver_data = ltc3886 },
555 	{ .name = "ltc3887", .driver_data = ltc3887 },
556 	{ .name = "ltc3889", .driver_data = ltc3889 },
557 	{ .name = "ltc7132", .driver_data = ltc7132 },
558 	{ .name = "ltc7841", .driver_data = ltc7841 },
559 	{ .name = "ltc7880", .driver_data = ltc7880 },
560 	{ .name = "ltm2987", .driver_data = ltm2987 },
561 	{ .name = "ltm4664", .driver_data = ltm4664 },
562 	{ .name = "ltm4673", .driver_data = ltm4673 },
563 	{ .name = "ltm4675", .driver_data = ltm4675 },
564 	{ .name = "ltm4676", .driver_data = ltm4676 },
565 	{ .name = "ltm4677", .driver_data = ltm4677 },
566 	{ .name = "ltm4678", .driver_data = ltm4678 },
567 	{ .name = "ltm4680", .driver_data = ltm4680 },
568 	{ .name = "ltm4686", .driver_data = ltm4686 },
569 	{ .name = "ltm4700", .driver_data = ltm4700 },
570 	{ }
571 };
572 MODULE_DEVICE_TABLE(i2c, ltc2978_id);
573 
574 #if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
575 #define LTC2978_ADC_RES	0xFFFF
576 #define LTC2978_N_ADC	122
577 #define LTC2978_MAX_UV	(LTC2978_ADC_RES * LTC2978_N_ADC)
578 #define LTC2978_UV_STEP	1000
579 #define LTC2978_N_VOLTAGES	((LTC2978_MAX_UV / LTC2978_UV_STEP) + 1)
580 
581 static const struct regulator_desc ltc2978_reg_desc[] = {
582 	PMBUS_REGULATOR_STEP("vout", 0, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
583 	PMBUS_REGULATOR_STEP("vout", 1, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
584 	PMBUS_REGULATOR_STEP("vout", 2, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
585 	PMBUS_REGULATOR_STEP("vout", 3, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
586 	PMBUS_REGULATOR_STEP("vout", 4, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
587 	PMBUS_REGULATOR_STEP("vout", 5, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
588 	PMBUS_REGULATOR_STEP("vout", 6, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
589 	PMBUS_REGULATOR_STEP("vout", 7, LTC2978_N_VOLTAGES, LTC2978_UV_STEP, 0),
590 };
591 
592 static const struct regulator_desc ltc2978_reg_desc_default[] = {
593 	PMBUS_REGULATOR("vout", 0),
594 	PMBUS_REGULATOR("vout", 1),
595 	PMBUS_REGULATOR("vout", 2),
596 	PMBUS_REGULATOR("vout", 3),
597 	PMBUS_REGULATOR("vout", 4),
598 	PMBUS_REGULATOR("vout", 5),
599 	PMBUS_REGULATOR("vout", 6),
600 	PMBUS_REGULATOR("vout", 7),
601 };
602 #endif /* CONFIG_SENSORS_LTC2978_REGULATOR */
603 
604 static int ltc2978_get_id(struct i2c_client *client)
605 {
606 	int chip_id;
607 
608 	chip_id = i2c_smbus_read_word_data(client, LTC2978_MFR_SPECIAL_ID);
609 	if (chip_id < 0) {
610 		const struct i2c_device_id *id;
611 		u8 buf[I2C_SMBUS_BLOCK_MAX];
612 		int ret;
613 
614 		ret = pmbus_read_smbus_i2c_block_data(client, PMBUS_MFR_ID, buf);
615 		if (ret < 0)
616 			return ret;
617 		if (ret < 3 || (strncmp(buf, "LTC", 3) && strncmp(buf, "ADI", 3)))
618 			return -ENODEV;
619 
620 		ret = pmbus_read_smbus_i2c_block_data(client, PMBUS_MFR_MODEL, buf);
621 		if (ret < 0)
622 			return ret;
623 		for (id = &ltc2978_id[0]; strlen(id->name); id++) {
624 			if (!strncasecmp(id->name, buf, strlen(id->name)))
625 				return (int)id->driver_data;
626 		}
627 		return -ENODEV;
628 	}
629 
630 	chip_id &= LTC2978_ID_MASK;
631 
632 	if (chip_id == LT7170_ID) {
633 		u8 buf[I2C_SMBUS_BLOCK_MAX];
634 		int ret;
635 
636 		ret = pmbus_read_smbus_i2c_block_data(client, PMBUS_IC_DEVICE_ID,
637 						      buf);
638 		if (ret < 0)
639 			return ret;
640 
641 		if (ret < 6)
642 			return -ENODEV;
643 
644 		if (!strncmp(buf, "LT7170", 6))
645 			return lt7170;
646 		if (!strncmp(buf, "LT7171", 6))
647 			return lt7171;
648 
649 		return -ENODEV;
650 	}
651 
652 	if (chip_id == LTC2972_ID)
653 		return ltc2972;
654 	else if (chip_id == LTC2974_ID)
655 		return ltc2974;
656 	else if (chip_id == LTC2975_ID)
657 		return ltc2975;
658 	else if (chip_id == LTC2977_ID)
659 		return ltc2977;
660 	else if (chip_id == LTC2978_ID_REV1 || chip_id == LTC2978_ID_REV2)
661 		return ltc2978;
662 	else if (chip_id == LTC2979_ID_A || chip_id == LTC2979_ID_B)
663 		return ltc2979;
664 	else if (chip_id == LTC2980_ID_A || chip_id == LTC2980_ID_B)
665 		return ltc2980;
666 	else if (chip_id == LTC3880_ID)
667 		return ltc3880;
668 	else if (chip_id == LTC3882_ID || chip_id == LTC3882_ID_D1)
669 		return ltc3882;
670 	else if (chip_id == LTC3883_ID)
671 		return ltc3883;
672 	else if (chip_id == LTC3884_ID)
673 		return ltc3884;
674 	else if (chip_id == LTC3886_ID)
675 		return ltc3886;
676 	else if (chip_id == LTC3887_ID)
677 		return ltc3887;
678 	else if (chip_id == LTC3889_ID)
679 		return ltc3889;
680 	else if (chip_id == LTC7132_ID)
681 		return ltc7132;
682 	else if (chip_id == LTC7841_ID)
683 		return ltc7841;
684 	else if (chip_id == LTC7880_ID)
685 		return ltc7880;
686 	else if (chip_id == LTM2987_ID_A || chip_id == LTM2987_ID_B)
687 		return ltm2987;
688 	else if (chip_id == LTM4664_ID)
689 		return ltm4664;
690 	else if (chip_id == LTM4673_ID || chip_id == LTM4673_ID_REV1)
691 		return ltm4673;
692 	else if (chip_id == LTM4675_ID)
693 		return ltm4675;
694 	else if (chip_id == LTM4676_ID_REV1 || chip_id == LTM4676_ID_REV2 ||
695 		 chip_id == LTM4676A_ID)
696 		return ltm4676;
697 	else if (chip_id == LTM4677_ID_REV1 || chip_id == LTM4677_ID_REV2)
698 		return ltm4677;
699 	else if (chip_id == LTM4678_ID_REV1 || chip_id == LTM4678_ID_REV2)
700 		return ltm4678;
701 	else if (chip_id == LTM4680_ID)
702 		return ltm4680;
703 	else if (chip_id == LTM4686_ID)
704 		return ltm4686;
705 	else if (chip_id == LTM4700_ID)
706 		return ltm4700;
707 
708 	dev_err(&client->dev, "Unsupported chip ID 0x%x\n", chip_id);
709 	return -ENODEV;
710 }
711 
712 static int ltc2978_probe(struct i2c_client *client)
713 {
714 	int i, chip_id;
715 	struct ltc2978_data *data;
716 	struct pmbus_driver_info *info;
717 	const struct i2c_device_id *id;
718 
719 	if (!i2c_check_functionality(client->adapter,
720 				     I2C_FUNC_SMBUS_READ_WORD_DATA))
721 		return -ENODEV;
722 
723 	data = devm_kzalloc(&client->dev, sizeof(struct ltc2978_data),
724 			    GFP_KERNEL);
725 	if (!data)
726 		return -ENOMEM;
727 
728 	chip_id = ltc2978_get_id(client);
729 	if (chip_id < 0)
730 		return chip_id;
731 
732 	data->id = chip_id;
733 	id = i2c_client_get_device_id(client);
734 	if (data->id != id->driver_data)
735 		dev_warn(&client->dev,
736 			 "Device mismatch: Configured %s (%d), detected %d\n",
737 			 id->name,
738 			 (int) id->driver_data,
739 			 chip_id);
740 
741 	info = &data->info;
742 	info->write_word_data = ltc2978_write_word_data;
743 	info->write_byte = ltc_write_byte;
744 	info->write_byte_data = ltc_write_byte_data;
745 	info->read_word_data = ltc_read_word_data;
746 	info->read_byte_data = ltc_read_byte_data;
747 
748 	data->vin_min = 0x7bff;
749 	data->vin_max = 0x7c00;
750 	for (i = 0; i < ARRAY_SIZE(data->vout_min); i++)
751 		data->vout_min[i] = 0xffff;
752 	for (i = 0; i < ARRAY_SIZE(data->iout_min); i++)
753 		data->iout_min[i] = 0xfbff;
754 	for (i = 0; i < ARRAY_SIZE(data->iout_max); i++)
755 		data->iout_max[i] = 0x7c00;
756 	for (i = 0; i < ARRAY_SIZE(data->temp_min); i++)
757 		data->temp_min[i] = 0x7bff;
758 	for (i = 0; i < ARRAY_SIZE(data->temp_max); i++)
759 		data->temp_max[i] = 0x7c00;
760 	data->temp2_max = 0x7c00;
761 
762 	switch (data->id) {
763 	case lt7170:
764 	case lt7171:
765 		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
766 		info->read_word_data = ltc3883_read_word_data;
767 		info->pages = LTC3883_NUM_PAGES;
768 		info->format[PSC_VOLTAGE_IN] = ieee754;
769 		info->format[PSC_VOLTAGE_OUT] = ieee754;
770 		info->format[PSC_CURRENT_OUT] = ieee754;
771 		info->format[PSC_TEMPERATURE] = ieee754;
772 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
773 		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
774 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
775 		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
776 		break;
777 	case ltc2972:
778 		info->read_word_data = ltc2975_read_word_data;
779 		info->pages = LTC2972_NUM_PAGES;
780 		info->func[0] = PMBUS_HAVE_IIN | PMBUS_HAVE_PIN
781 		  | PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
782 		  | PMBUS_HAVE_TEMP2;
783 		for (i = 0; i < info->pages; i++) {
784 			info->func[i] |= PMBUS_HAVE_VOUT
785 			  | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_POUT
786 			  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
787 			  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
788 		}
789 		break;
790 	case ltc2974:
791 		info->read_word_data = ltc2974_read_word_data;
792 		info->pages = LTC2974_NUM_PAGES;
793 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
794 		  | PMBUS_HAVE_TEMP2;
795 		for (i = 0; i < info->pages; i++) {
796 			info->func[i] |= PMBUS_HAVE_VOUT
797 			  | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_POUT
798 			  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
799 			  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
800 		}
801 		break;
802 	case ltc2975:
803 		info->read_word_data = ltc2975_read_word_data;
804 		info->pages = LTC2974_NUM_PAGES;
805 		info->func[0] = PMBUS_HAVE_IIN | PMBUS_HAVE_PIN
806 		  | PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
807 		  | PMBUS_HAVE_TEMP2;
808 		for (i = 0; i < info->pages; i++) {
809 			info->func[i] |= PMBUS_HAVE_VOUT
810 			  | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_POUT
811 			  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
812 			  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT;
813 		}
814 		break;
815 
816 	case ltc2977:
817 	case ltc2978:
818 	case ltc2979:
819 	case ltc2980:
820 	case ltm2987:
821 		info->read_word_data = ltc2978_read_word_data;
822 		info->pages = LTC2978_NUM_PAGES;
823 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
824 		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
825 		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
826 		for (i = 1; i < LTC2978_NUM_PAGES; i++) {
827 			info->func[i] = PMBUS_HAVE_VOUT
828 			  | PMBUS_HAVE_STATUS_VOUT;
829 		}
830 		break;
831 	case ltc3880:
832 	case ltc3887:
833 	case ltm4675:
834 	case ltm4676:
835 	case ltm4677:
836 	case ltm4686:
837 		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
838 		info->read_word_data = ltc3880_read_word_data;
839 		info->pages = LTC3880_NUM_PAGES;
840 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
841 		  | PMBUS_HAVE_STATUS_INPUT
842 		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
843 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
844 		  | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
845 		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
846 		info->func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
847 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
848 		  | PMBUS_HAVE_POUT
849 		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
850 		break;
851 	case ltc3882:
852 		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
853 		info->read_word_data = ltc3880_read_word_data;
854 		info->pages = LTC3880_NUM_PAGES;
855 		info->func[0] = PMBUS_HAVE_VIN
856 		  | PMBUS_HAVE_STATUS_INPUT
857 		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
858 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
859 		  | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
860 		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
861 		info->func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
862 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
863 		  | PMBUS_HAVE_POUT
864 		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
865 		break;
866 	case ltc3883:
867 		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
868 		info->read_word_data = ltc3883_read_word_data;
869 		info->pages = LTC3883_NUM_PAGES;
870 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
871 		  | PMBUS_HAVE_STATUS_INPUT
872 		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
873 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
874 		  | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
875 		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
876 		break;
877 	case ltc3884:
878 	case ltc3886:
879 	case ltc3889:
880 	case ltc7132:
881 	case ltc7880:
882 	case ltm4664:
883 	case ltm4678:
884 	case ltm4680:
885 	case ltm4700:
886 		data->features |= FEAT_CLEAR_PEAKS | FEAT_NEEDS_POLLING;
887 		info->read_word_data = ltc3883_read_word_data;
888 		info->pages = LTC3880_NUM_PAGES;
889 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
890 		  | PMBUS_HAVE_STATUS_INPUT
891 		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
892 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
893 		  | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
894 		  | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
895 		info->func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
896 		  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
897 		  | PMBUS_HAVE_POUT
898 		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
899 		break;
900 	case ltc7841:
901 		data->features |= FEAT_CLEAR_PEAKS;
902 		info->read_word_data = ltc3883_read_word_data;
903 		info->pages = LTC3883_NUM_PAGES;
904 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
905 		  | PMBUS_HAVE_STATUS_INPUT
906 		  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
907 		  | PMBUS_HAVE_IOUT
908 		  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
909 		break;
910 	case ltm4673:
911 		data->features |= FEAT_NEEDS_POLLING;
912 		info->read_word_data = ltc2975_read_word_data;
913 		info->pages = LTC2974_NUM_PAGES;
914 		info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
915 		  | PMBUS_HAVE_TEMP2;
916 		for (i = 0; i < info->pages; i++) {
917 			info->func[i] |= PMBUS_HAVE_IIN
918 			  | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
919 			  | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
920 			  | PMBUS_HAVE_PIN
921 			  | PMBUS_HAVE_POUT
922 			  | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP;
923 		}
924 		break;
925 	default:
926 		return -ENODEV;
927 	}
928 
929 #if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
930 	info->num_regulators = info->pages;
931 	switch (data->id) {
932 	case ltc2972:
933 	case ltc2974:
934 	case ltc2975:
935 	case ltc2977:
936 	case ltc2978:
937 	case ltc2979:
938 	case ltc2980:
939 	case ltm2987:
940 		info->reg_desc = ltc2978_reg_desc;
941 		if (info->num_regulators > ARRAY_SIZE(ltc2978_reg_desc)) {
942 			dev_warn(&client->dev, "num_regulators too large!");
943 			info->num_regulators = ARRAY_SIZE(ltc2978_reg_desc);
944 		}
945 		break;
946 	default:
947 		info->reg_desc = ltc2978_reg_desc_default;
948 		if (info->num_regulators > ARRAY_SIZE(ltc2978_reg_desc_default)) {
949 			dev_warn(&client->dev, "num_regulators too large!");
950 			info->num_regulators =
951 			    ARRAY_SIZE(ltc2978_reg_desc_default);
952 		}
953 		break;
954 	}
955 #endif
956 
957 	return pmbus_do_probe(client, info);
958 }
959 
960 
961 #ifdef CONFIG_OF
962 static const struct of_device_id ltc2978_of_match[] = {
963 	{ .compatible = "lltc,lt7170" },
964 	{ .compatible = "lltc,lt7171" },
965 	{ .compatible = "lltc,ltc2972" },
966 	{ .compatible = "lltc,ltc2974" },
967 	{ .compatible = "lltc,ltc2975" },
968 	{ .compatible = "lltc,ltc2977" },
969 	{ .compatible = "lltc,ltc2978" },
970 	{ .compatible = "lltc,ltc2979" },
971 	{ .compatible = "lltc,ltc2980" },
972 	{ .compatible = "lltc,ltc3880" },
973 	{ .compatible = "lltc,ltc3882" },
974 	{ .compatible = "lltc,ltc3883" },
975 	{ .compatible = "lltc,ltc3884" },
976 	{ .compatible = "lltc,ltc3886" },
977 	{ .compatible = "lltc,ltc3887" },
978 	{ .compatible = "lltc,ltc3889" },
979 	{ .compatible = "lltc,ltc7132" },
980 	{ .compatible = "lltc,ltc7841" },
981 	{ .compatible = "lltc,ltc7880" },
982 	{ .compatible = "lltc,ltm2987" },
983 	{ .compatible = "lltc,ltm4664" },
984 	{ .compatible = "lltc,ltm4673" },
985 	{ .compatible = "lltc,ltm4675" },
986 	{ .compatible = "lltc,ltm4676" },
987 	{ .compatible = "lltc,ltm4677" },
988 	{ .compatible = "lltc,ltm4678" },
989 	{ .compatible = "lltc,ltm4680" },
990 	{ .compatible = "lltc,ltm4686" },
991 	{ .compatible = "lltc,ltm4700" },
992 	{ }
993 };
994 MODULE_DEVICE_TABLE(of, ltc2978_of_match);
995 #endif
996 
997 static struct i2c_driver ltc2978_driver = {
998 	.driver = {
999 		   .name = "ltc2978",
1000 		   .of_match_table = of_match_ptr(ltc2978_of_match),
1001 		   },
1002 	.probe = ltc2978_probe,
1003 	.id_table = ltc2978_id,
1004 };
1005 
1006 module_i2c_driver(ltc2978_driver);
1007 
1008 MODULE_AUTHOR("Guenter Roeck");
1009 MODULE_DESCRIPTION("PMBus driver for LTC2978 and compatible chips");
1010 MODULE_LICENSE("GPL");
1011 MODULE_IMPORT_NS("PMBUS");
1012