xref: /openbmc/linux/drivers/hwmon/pmbus/pmbus_core.c (revision 0da85d1e)
1 /*
2  * Hardware monitoring driver for PMBus devices
3  *
4  * Copyright (c) 2010, 2011 Ericsson AB.
5  * Copyright (c) 2012 Guenter Roeck
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/err.h>
26 #include <linux/slab.h>
27 #include <linux/i2c.h>
28 #include <linux/hwmon.h>
29 #include <linux/hwmon-sysfs.h>
30 #include <linux/jiffies.h>
31 #include <linux/i2c/pmbus.h>
32 #include <linux/regulator/driver.h>
33 #include <linux/regulator/machine.h>
34 #include "pmbus.h"
35 
36 /*
37  * Number of additional attribute pointers to allocate
38  * with each call to krealloc
39  */
40 #define PMBUS_ATTR_ALLOC_SIZE	32
41 
42 /*
43  * Index into status register array, per status register group
44  */
45 #define PB_STATUS_BASE		0
46 #define PB_STATUS_VOUT_BASE	(PB_STATUS_BASE + PMBUS_PAGES)
47 #define PB_STATUS_IOUT_BASE	(PB_STATUS_VOUT_BASE + PMBUS_PAGES)
48 #define PB_STATUS_FAN_BASE	(PB_STATUS_IOUT_BASE + PMBUS_PAGES)
49 #define PB_STATUS_FAN34_BASE	(PB_STATUS_FAN_BASE + PMBUS_PAGES)
50 #define PB_STATUS_TEMP_BASE	(PB_STATUS_FAN34_BASE + PMBUS_PAGES)
51 #define PB_STATUS_INPUT_BASE	(PB_STATUS_TEMP_BASE + PMBUS_PAGES)
52 #define PB_STATUS_VMON_BASE	(PB_STATUS_INPUT_BASE + 1)
53 
54 #define PB_NUM_STATUS_REG	(PB_STATUS_VMON_BASE + 1)
55 
56 #define PMBUS_NAME_SIZE		24
57 
58 struct pmbus_sensor {
59 	struct pmbus_sensor *next;
60 	char name[PMBUS_NAME_SIZE];	/* sysfs sensor name */
61 	struct device_attribute attribute;
62 	u8 page;		/* page number */
63 	u16 reg;		/* register */
64 	enum pmbus_sensor_classes class;	/* sensor class */
65 	bool update;		/* runtime sensor update needed */
66 	int data;		/* Sensor data.
67 				   Negative if there was a read error */
68 };
69 #define to_pmbus_sensor(_attr) \
70 	container_of(_attr, struct pmbus_sensor, attribute)
71 
72 struct pmbus_boolean {
73 	char name[PMBUS_NAME_SIZE];	/* sysfs boolean name */
74 	struct sensor_device_attribute attribute;
75 	struct pmbus_sensor *s1;
76 	struct pmbus_sensor *s2;
77 };
78 #define to_pmbus_boolean(_attr) \
79 	container_of(_attr, struct pmbus_boolean, attribute)
80 
81 struct pmbus_label {
82 	char name[PMBUS_NAME_SIZE];	/* sysfs label name */
83 	struct device_attribute attribute;
84 	char label[PMBUS_NAME_SIZE];	/* label */
85 };
86 #define to_pmbus_label(_attr) \
87 	container_of(_attr, struct pmbus_label, attribute)
88 
89 struct pmbus_data {
90 	struct device *dev;
91 	struct device *hwmon_dev;
92 
93 	u32 flags;		/* from platform data */
94 
95 	int exponent[PMBUS_PAGES];
96 				/* linear mode: exponent for output voltages */
97 
98 	const struct pmbus_driver_info *info;
99 
100 	int max_attributes;
101 	int num_attributes;
102 	struct attribute_group group;
103 	const struct attribute_group *groups[2];
104 
105 	struct pmbus_sensor *sensors;
106 
107 	struct mutex update_lock;
108 	bool valid;
109 	unsigned long last_updated;	/* in jiffies */
110 
111 	/*
112 	 * A single status register covers multiple attributes,
113 	 * so we keep them all together.
114 	 */
115 	u8 status[PB_NUM_STATUS_REG];
116 	u8 status_register;
117 
118 	u8 currpage;
119 };
120 
121 void pmbus_clear_cache(struct i2c_client *client)
122 {
123 	struct pmbus_data *data = i2c_get_clientdata(client);
124 
125 	data->valid = false;
126 }
127 EXPORT_SYMBOL_GPL(pmbus_clear_cache);
128 
129 int pmbus_set_page(struct i2c_client *client, u8 page)
130 {
131 	struct pmbus_data *data = i2c_get_clientdata(client);
132 	int rv = 0;
133 	int newpage;
134 
135 	if (page != data->currpage) {
136 		rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
137 		newpage = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
138 		if (newpage != page)
139 			rv = -EIO;
140 		else
141 			data->currpage = page;
142 	}
143 	return rv;
144 }
145 EXPORT_SYMBOL_GPL(pmbus_set_page);
146 
147 int pmbus_write_byte(struct i2c_client *client, int page, u8 value)
148 {
149 	int rv;
150 
151 	if (page >= 0) {
152 		rv = pmbus_set_page(client, page);
153 		if (rv < 0)
154 			return rv;
155 	}
156 
157 	return i2c_smbus_write_byte(client, value);
158 }
159 EXPORT_SYMBOL_GPL(pmbus_write_byte);
160 
161 /*
162  * _pmbus_write_byte() is similar to pmbus_write_byte(), but checks if
163  * a device specific mapping function exists and calls it if necessary.
164  */
165 static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value)
166 {
167 	struct pmbus_data *data = i2c_get_clientdata(client);
168 	const struct pmbus_driver_info *info = data->info;
169 	int status;
170 
171 	if (info->write_byte) {
172 		status = info->write_byte(client, page, value);
173 		if (status != -ENODATA)
174 			return status;
175 	}
176 	return pmbus_write_byte(client, page, value);
177 }
178 
179 int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word)
180 {
181 	int rv;
182 
183 	rv = pmbus_set_page(client, page);
184 	if (rv < 0)
185 		return rv;
186 
187 	return i2c_smbus_write_word_data(client, reg, word);
188 }
189 EXPORT_SYMBOL_GPL(pmbus_write_word_data);
190 
191 /*
192  * _pmbus_write_word_data() is similar to pmbus_write_word_data(), but checks if
193  * a device specific mapping function exists and calls it if necessary.
194  */
195 static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg,
196 				  u16 word)
197 {
198 	struct pmbus_data *data = i2c_get_clientdata(client);
199 	const struct pmbus_driver_info *info = data->info;
200 	int status;
201 
202 	if (info->write_word_data) {
203 		status = info->write_word_data(client, page, reg, word);
204 		if (status != -ENODATA)
205 			return status;
206 	}
207 	if (reg >= PMBUS_VIRT_BASE)
208 		return -ENXIO;
209 	return pmbus_write_word_data(client, page, reg, word);
210 }
211 
212 int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg)
213 {
214 	int rv;
215 
216 	rv = pmbus_set_page(client, page);
217 	if (rv < 0)
218 		return rv;
219 
220 	return i2c_smbus_read_word_data(client, reg);
221 }
222 EXPORT_SYMBOL_GPL(pmbus_read_word_data);
223 
224 /*
225  * _pmbus_read_word_data() is similar to pmbus_read_word_data(), but checks if
226  * a device specific mapping function exists and calls it if necessary.
227  */
228 static int _pmbus_read_word_data(struct i2c_client *client, int page, int reg)
229 {
230 	struct pmbus_data *data = i2c_get_clientdata(client);
231 	const struct pmbus_driver_info *info = data->info;
232 	int status;
233 
234 	if (info->read_word_data) {
235 		status = info->read_word_data(client, page, reg);
236 		if (status != -ENODATA)
237 			return status;
238 	}
239 	if (reg >= PMBUS_VIRT_BASE)
240 		return -ENXIO;
241 	return pmbus_read_word_data(client, page, reg);
242 }
243 
244 int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg)
245 {
246 	int rv;
247 
248 	if (page >= 0) {
249 		rv = pmbus_set_page(client, page);
250 		if (rv < 0)
251 			return rv;
252 	}
253 
254 	return i2c_smbus_read_byte_data(client, reg);
255 }
256 EXPORT_SYMBOL_GPL(pmbus_read_byte_data);
257 
258 int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value)
259 {
260 	int rv;
261 
262 	rv = pmbus_set_page(client, page);
263 	if (rv < 0)
264 		return rv;
265 
266 	return i2c_smbus_write_byte_data(client, reg, value);
267 }
268 EXPORT_SYMBOL_GPL(pmbus_write_byte_data);
269 
270 int pmbus_update_byte_data(struct i2c_client *client, int page, u8 reg,
271 			   u8 mask, u8 value)
272 {
273 	unsigned int tmp;
274 	int rv;
275 
276 	rv = pmbus_read_byte_data(client, page, reg);
277 	if (rv < 0)
278 		return rv;
279 
280 	tmp = (rv & ~mask) | (value & mask);
281 
282 	if (tmp != rv)
283 		rv = pmbus_write_byte_data(client, page, reg, tmp);
284 
285 	return rv;
286 }
287 EXPORT_SYMBOL_GPL(pmbus_update_byte_data);
288 
289 /*
290  * _pmbus_read_byte_data() is similar to pmbus_read_byte_data(), but checks if
291  * a device specific mapping function exists and calls it if necessary.
292  */
293 static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
294 {
295 	struct pmbus_data *data = i2c_get_clientdata(client);
296 	const struct pmbus_driver_info *info = data->info;
297 	int status;
298 
299 	if (info->read_byte_data) {
300 		status = info->read_byte_data(client, page, reg);
301 		if (status != -ENODATA)
302 			return status;
303 	}
304 	return pmbus_read_byte_data(client, page, reg);
305 }
306 
307 static void pmbus_clear_fault_page(struct i2c_client *client, int page)
308 {
309 	_pmbus_write_byte(client, page, PMBUS_CLEAR_FAULTS);
310 }
311 
312 void pmbus_clear_faults(struct i2c_client *client)
313 {
314 	struct pmbus_data *data = i2c_get_clientdata(client);
315 	int i;
316 
317 	for (i = 0; i < data->info->pages; i++)
318 		pmbus_clear_fault_page(client, i);
319 }
320 EXPORT_SYMBOL_GPL(pmbus_clear_faults);
321 
322 static int pmbus_check_status_cml(struct i2c_client *client)
323 {
324 	struct pmbus_data *data = i2c_get_clientdata(client);
325 	int status, status2;
326 
327 	status = _pmbus_read_byte_data(client, -1, data->status_register);
328 	if (status < 0 || (status & PB_STATUS_CML)) {
329 		status2 = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML);
330 		if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND))
331 			return -EIO;
332 	}
333 	return 0;
334 }
335 
336 static bool pmbus_check_register(struct i2c_client *client,
337 				 int (*func)(struct i2c_client *client,
338 					     int page, int reg),
339 				 int page, int reg)
340 {
341 	int rv;
342 	struct pmbus_data *data = i2c_get_clientdata(client);
343 
344 	rv = func(client, page, reg);
345 	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
346 		rv = pmbus_check_status_cml(client);
347 	pmbus_clear_fault_page(client, -1);
348 	return rv >= 0;
349 }
350 
351 bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg)
352 {
353 	return pmbus_check_register(client, _pmbus_read_byte_data, page, reg);
354 }
355 EXPORT_SYMBOL_GPL(pmbus_check_byte_register);
356 
357 bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
358 {
359 	return pmbus_check_register(client, _pmbus_read_word_data, page, reg);
360 }
361 EXPORT_SYMBOL_GPL(pmbus_check_word_register);
362 
363 const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
364 {
365 	struct pmbus_data *data = i2c_get_clientdata(client);
366 
367 	return data->info;
368 }
369 EXPORT_SYMBOL_GPL(pmbus_get_driver_info);
370 
371 static struct _pmbus_status {
372 	u32 func;
373 	u16 base;
374 	u16 reg;
375 } pmbus_status[] = {
376 	{ PMBUS_HAVE_STATUS_VOUT, PB_STATUS_VOUT_BASE, PMBUS_STATUS_VOUT },
377 	{ PMBUS_HAVE_STATUS_IOUT, PB_STATUS_IOUT_BASE, PMBUS_STATUS_IOUT },
378 	{ PMBUS_HAVE_STATUS_TEMP, PB_STATUS_TEMP_BASE,
379 	  PMBUS_STATUS_TEMPERATURE },
380 	{ PMBUS_HAVE_STATUS_FAN12, PB_STATUS_FAN_BASE, PMBUS_STATUS_FAN_12 },
381 	{ PMBUS_HAVE_STATUS_FAN34, PB_STATUS_FAN34_BASE, PMBUS_STATUS_FAN_34 },
382 };
383 
384 static struct pmbus_data *pmbus_update_device(struct device *dev)
385 {
386 	struct i2c_client *client = to_i2c_client(dev->parent);
387 	struct pmbus_data *data = i2c_get_clientdata(client);
388 	const struct pmbus_driver_info *info = data->info;
389 	struct pmbus_sensor *sensor;
390 
391 	mutex_lock(&data->update_lock);
392 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
393 		int i, j;
394 
395 		for (i = 0; i < info->pages; i++) {
396 			data->status[PB_STATUS_BASE + i]
397 			    = _pmbus_read_byte_data(client, i,
398 						    data->status_register);
399 			for (j = 0; j < ARRAY_SIZE(pmbus_status); j++) {
400 				struct _pmbus_status *s = &pmbus_status[j];
401 
402 				if (!(info->func[i] & s->func))
403 					continue;
404 				data->status[s->base + i]
405 					= _pmbus_read_byte_data(client, i,
406 								s->reg);
407 			}
408 		}
409 
410 		if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
411 			data->status[PB_STATUS_INPUT_BASE]
412 			  = _pmbus_read_byte_data(client, 0,
413 						  PMBUS_STATUS_INPUT);
414 
415 		if (info->func[0] & PMBUS_HAVE_STATUS_VMON)
416 			data->status[PB_STATUS_VMON_BASE]
417 			  = _pmbus_read_byte_data(client, 0,
418 						  PMBUS_VIRT_STATUS_VMON);
419 
420 		for (sensor = data->sensors; sensor; sensor = sensor->next) {
421 			if (!data->valid || sensor->update)
422 				sensor->data
423 				    = _pmbus_read_word_data(client,
424 							    sensor->page,
425 							    sensor->reg);
426 		}
427 		pmbus_clear_faults(client);
428 		data->last_updated = jiffies;
429 		data->valid = 1;
430 	}
431 	mutex_unlock(&data->update_lock);
432 	return data;
433 }
434 
435 /*
436  * Convert linear sensor values to milli- or micro-units
437  * depending on sensor type.
438  */
439 static long pmbus_reg2data_linear(struct pmbus_data *data,
440 				  struct pmbus_sensor *sensor)
441 {
442 	s16 exponent;
443 	s32 mantissa;
444 	long val;
445 
446 	if (sensor->class == PSC_VOLTAGE_OUT) {	/* LINEAR16 */
447 		exponent = data->exponent[sensor->page];
448 		mantissa = (u16) sensor->data;
449 	} else {				/* LINEAR11 */
450 		exponent = ((s16)sensor->data) >> 11;
451 		mantissa = ((s16)((sensor->data & 0x7ff) << 5)) >> 5;
452 	}
453 
454 	val = mantissa;
455 
456 	/* scale result to milli-units for all sensors except fans */
457 	if (sensor->class != PSC_FAN)
458 		val = val * 1000L;
459 
460 	/* scale result to micro-units for power sensors */
461 	if (sensor->class == PSC_POWER)
462 		val = val * 1000L;
463 
464 	if (exponent >= 0)
465 		val <<= exponent;
466 	else
467 		val >>= -exponent;
468 
469 	return val;
470 }
471 
472 /*
473  * Convert direct sensor values to milli- or micro-units
474  * depending on sensor type.
475  */
476 static long pmbus_reg2data_direct(struct pmbus_data *data,
477 				  struct pmbus_sensor *sensor)
478 {
479 	long val = (s16) sensor->data;
480 	long m, b, R;
481 
482 	m = data->info->m[sensor->class];
483 	b = data->info->b[sensor->class];
484 	R = data->info->R[sensor->class];
485 
486 	if (m == 0)
487 		return 0;
488 
489 	/* X = 1/m * (Y * 10^-R - b) */
490 	R = -R;
491 	/* scale result to milli-units for everything but fans */
492 	if (sensor->class != PSC_FAN) {
493 		R += 3;
494 		b *= 1000;
495 	}
496 
497 	/* scale result to micro-units for power sensors */
498 	if (sensor->class == PSC_POWER) {
499 		R += 3;
500 		b *= 1000;
501 	}
502 
503 	while (R > 0) {
504 		val *= 10;
505 		R--;
506 	}
507 	while (R < 0) {
508 		val = DIV_ROUND_CLOSEST(val, 10);
509 		R++;
510 	}
511 
512 	return (val - b) / m;
513 }
514 
515 /*
516  * Convert VID sensor values to milli- or micro-units
517  * depending on sensor type.
518  * We currently only support VR11.
519  */
520 static long pmbus_reg2data_vid(struct pmbus_data *data,
521 			       struct pmbus_sensor *sensor)
522 {
523 	long val = sensor->data;
524 
525 	if (val < 0x02 || val > 0xb2)
526 		return 0;
527 	return DIV_ROUND_CLOSEST(160000 - (val - 2) * 625, 100);
528 }
529 
530 static long pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
531 {
532 	long val;
533 
534 	switch (data->info->format[sensor->class]) {
535 	case direct:
536 		val = pmbus_reg2data_direct(data, sensor);
537 		break;
538 	case vid:
539 		val = pmbus_reg2data_vid(data, sensor);
540 		break;
541 	case linear:
542 	default:
543 		val = pmbus_reg2data_linear(data, sensor);
544 		break;
545 	}
546 	return val;
547 }
548 
549 #define MAX_MANTISSA	(1023 * 1000)
550 #define MIN_MANTISSA	(511 * 1000)
551 
552 static u16 pmbus_data2reg_linear(struct pmbus_data *data,
553 				 struct pmbus_sensor *sensor, long val)
554 {
555 	s16 exponent = 0, mantissa;
556 	bool negative = false;
557 
558 	/* simple case */
559 	if (val == 0)
560 		return 0;
561 
562 	if (sensor->class == PSC_VOLTAGE_OUT) {
563 		/* LINEAR16 does not support negative voltages */
564 		if (val < 0)
565 			return 0;
566 
567 		/*
568 		 * For a static exponents, we don't have a choice
569 		 * but to adjust the value to it.
570 		 */
571 		if (data->exponent[sensor->page] < 0)
572 			val <<= -data->exponent[sensor->page];
573 		else
574 			val >>= data->exponent[sensor->page];
575 		val = DIV_ROUND_CLOSEST(val, 1000);
576 		return val & 0xffff;
577 	}
578 
579 	if (val < 0) {
580 		negative = true;
581 		val = -val;
582 	}
583 
584 	/* Power is in uW. Convert to mW before converting. */
585 	if (sensor->class == PSC_POWER)
586 		val = DIV_ROUND_CLOSEST(val, 1000L);
587 
588 	/*
589 	 * For simplicity, convert fan data to milli-units
590 	 * before calculating the exponent.
591 	 */
592 	if (sensor->class == PSC_FAN)
593 		val = val * 1000;
594 
595 	/* Reduce large mantissa until it fits into 10 bit */
596 	while (val >= MAX_MANTISSA && exponent < 15) {
597 		exponent++;
598 		val >>= 1;
599 	}
600 	/* Increase small mantissa to improve precision */
601 	while (val < MIN_MANTISSA && exponent > -15) {
602 		exponent--;
603 		val <<= 1;
604 	}
605 
606 	/* Convert mantissa from milli-units to units */
607 	mantissa = DIV_ROUND_CLOSEST(val, 1000);
608 
609 	/* Ensure that resulting number is within range */
610 	if (mantissa > 0x3ff)
611 		mantissa = 0x3ff;
612 
613 	/* restore sign */
614 	if (negative)
615 		mantissa = -mantissa;
616 
617 	/* Convert to 5 bit exponent, 11 bit mantissa */
618 	return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
619 }
620 
621 static u16 pmbus_data2reg_direct(struct pmbus_data *data,
622 				 struct pmbus_sensor *sensor, long val)
623 {
624 	long m, b, R;
625 
626 	m = data->info->m[sensor->class];
627 	b = data->info->b[sensor->class];
628 	R = data->info->R[sensor->class];
629 
630 	/* Power is in uW. Adjust R and b. */
631 	if (sensor->class == PSC_POWER) {
632 		R -= 3;
633 		b *= 1000;
634 	}
635 
636 	/* Calculate Y = (m * X + b) * 10^R */
637 	if (sensor->class != PSC_FAN) {
638 		R -= 3;		/* Adjust R and b for data in milli-units */
639 		b *= 1000;
640 	}
641 	val = val * m + b;
642 
643 	while (R > 0) {
644 		val *= 10;
645 		R--;
646 	}
647 	while (R < 0) {
648 		val = DIV_ROUND_CLOSEST(val, 10);
649 		R++;
650 	}
651 
652 	return val;
653 }
654 
655 static u16 pmbus_data2reg_vid(struct pmbus_data *data,
656 			      struct pmbus_sensor *sensor, long val)
657 {
658 	val = clamp_val(val, 500, 1600);
659 
660 	return 2 + DIV_ROUND_CLOSEST((1600 - val) * 100, 625);
661 }
662 
663 static u16 pmbus_data2reg(struct pmbus_data *data,
664 			  struct pmbus_sensor *sensor, long val)
665 {
666 	u16 regval;
667 
668 	switch (data->info->format[sensor->class]) {
669 	case direct:
670 		regval = pmbus_data2reg_direct(data, sensor, val);
671 		break;
672 	case vid:
673 		regval = pmbus_data2reg_vid(data, sensor, val);
674 		break;
675 	case linear:
676 	default:
677 		regval = pmbus_data2reg_linear(data, sensor, val);
678 		break;
679 	}
680 	return regval;
681 }
682 
683 /*
684  * Return boolean calculated from converted data.
685  * <index> defines a status register index and mask.
686  * The mask is in the lower 8 bits, the register index is in bits 8..23.
687  *
688  * The associated pmbus_boolean structure contains optional pointers to two
689  * sensor attributes. If specified, those attributes are compared against each
690  * other to determine if a limit has been exceeded.
691  *
692  * If the sensor attribute pointers are NULL, the function returns true if
693  * (status[reg] & mask) is true.
694  *
695  * If sensor attribute pointers are provided, a comparison against a specified
696  * limit has to be performed to determine the boolean result.
697  * In this case, the function returns true if v1 >= v2 (where v1 and v2 are
698  * sensor values referenced by sensor attribute pointers s1 and s2).
699  *
700  * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>.
701  * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>.
702  *
703  * If a negative value is stored in any of the referenced registers, this value
704  * reflects an error code which will be returned.
705  */
706 static int pmbus_get_boolean(struct pmbus_data *data, struct pmbus_boolean *b,
707 			     int index)
708 {
709 	struct pmbus_sensor *s1 = b->s1;
710 	struct pmbus_sensor *s2 = b->s2;
711 	u16 reg = (index >> 8) & 0xffff;
712 	u8 mask = index & 0xff;
713 	int ret, status;
714 	u8 regval;
715 
716 	status = data->status[reg];
717 	if (status < 0)
718 		return status;
719 
720 	regval = status & mask;
721 	if (!s1 && !s2) {
722 		ret = !!regval;
723 	} else if (!s1 || !s2) {
724 		WARN(1, "Bad boolean descriptor %p: s1=%p, s2=%p\n", b, s1, s2);
725 		return 0;
726 	} else {
727 		long v1, v2;
728 
729 		if (s1->data < 0)
730 			return s1->data;
731 		if (s2->data < 0)
732 			return s2->data;
733 
734 		v1 = pmbus_reg2data(data, s1);
735 		v2 = pmbus_reg2data(data, s2);
736 		ret = !!(regval && v1 >= v2);
737 	}
738 	return ret;
739 }
740 
741 static ssize_t pmbus_show_boolean(struct device *dev,
742 				  struct device_attribute *da, char *buf)
743 {
744 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
745 	struct pmbus_boolean *boolean = to_pmbus_boolean(attr);
746 	struct pmbus_data *data = pmbus_update_device(dev);
747 	int val;
748 
749 	val = pmbus_get_boolean(data, boolean, attr->index);
750 	if (val < 0)
751 		return val;
752 	return snprintf(buf, PAGE_SIZE, "%d\n", val);
753 }
754 
755 static ssize_t pmbus_show_sensor(struct device *dev,
756 				 struct device_attribute *devattr, char *buf)
757 {
758 	struct pmbus_data *data = pmbus_update_device(dev);
759 	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
760 
761 	if (sensor->data < 0)
762 		return sensor->data;
763 
764 	return snprintf(buf, PAGE_SIZE, "%ld\n", pmbus_reg2data(data, sensor));
765 }
766 
767 static ssize_t pmbus_set_sensor(struct device *dev,
768 				struct device_attribute *devattr,
769 				const char *buf, size_t count)
770 {
771 	struct i2c_client *client = to_i2c_client(dev->parent);
772 	struct pmbus_data *data = i2c_get_clientdata(client);
773 	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
774 	ssize_t rv = count;
775 	long val = 0;
776 	int ret;
777 	u16 regval;
778 
779 	if (kstrtol(buf, 10, &val) < 0)
780 		return -EINVAL;
781 
782 	mutex_lock(&data->update_lock);
783 	regval = pmbus_data2reg(data, sensor, val);
784 	ret = _pmbus_write_word_data(client, sensor->page, sensor->reg, regval);
785 	if (ret < 0)
786 		rv = ret;
787 	else
788 		sensor->data = regval;
789 	mutex_unlock(&data->update_lock);
790 	return rv;
791 }
792 
793 static ssize_t pmbus_show_label(struct device *dev,
794 				struct device_attribute *da, char *buf)
795 {
796 	struct pmbus_label *label = to_pmbus_label(da);
797 
798 	return snprintf(buf, PAGE_SIZE, "%s\n", label->label);
799 }
800 
801 static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
802 {
803 	if (data->num_attributes >= data->max_attributes - 1) {
804 		int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE;
805 		void *new_attrs = krealloc(data->group.attrs,
806 					   new_max_attrs * sizeof(void *),
807 					   GFP_KERNEL);
808 		if (!new_attrs)
809 			return -ENOMEM;
810 		data->group.attrs = new_attrs;
811 		data->max_attributes = new_max_attrs;
812 	}
813 
814 	data->group.attrs[data->num_attributes++] = attr;
815 	data->group.attrs[data->num_attributes] = NULL;
816 	return 0;
817 }
818 
819 static void pmbus_dev_attr_init(struct device_attribute *dev_attr,
820 				const char *name,
821 				umode_t mode,
822 				ssize_t (*show)(struct device *dev,
823 						struct device_attribute *attr,
824 						char *buf),
825 				ssize_t (*store)(struct device *dev,
826 						 struct device_attribute *attr,
827 						 const char *buf, size_t count))
828 {
829 	sysfs_attr_init(&dev_attr->attr);
830 	dev_attr->attr.name = name;
831 	dev_attr->attr.mode = mode;
832 	dev_attr->show = show;
833 	dev_attr->store = store;
834 }
835 
836 static void pmbus_attr_init(struct sensor_device_attribute *a,
837 			    const char *name,
838 			    umode_t mode,
839 			    ssize_t (*show)(struct device *dev,
840 					    struct device_attribute *attr,
841 					    char *buf),
842 			    ssize_t (*store)(struct device *dev,
843 					     struct device_attribute *attr,
844 					     const char *buf, size_t count),
845 			    int idx)
846 {
847 	pmbus_dev_attr_init(&a->dev_attr, name, mode, show, store);
848 	a->index = idx;
849 }
850 
851 static int pmbus_add_boolean(struct pmbus_data *data,
852 			     const char *name, const char *type, int seq,
853 			     struct pmbus_sensor *s1,
854 			     struct pmbus_sensor *s2,
855 			     u16 reg, u8 mask)
856 {
857 	struct pmbus_boolean *boolean;
858 	struct sensor_device_attribute *a;
859 
860 	boolean = devm_kzalloc(data->dev, sizeof(*boolean), GFP_KERNEL);
861 	if (!boolean)
862 		return -ENOMEM;
863 
864 	a = &boolean->attribute;
865 
866 	snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
867 		 name, seq, type);
868 	boolean->s1 = s1;
869 	boolean->s2 = s2;
870 	pmbus_attr_init(a, boolean->name, S_IRUGO, pmbus_show_boolean, NULL,
871 			(reg << 8) | mask);
872 
873 	return pmbus_add_attribute(data, &a->dev_attr.attr);
874 }
875 
876 static struct pmbus_sensor *pmbus_add_sensor(struct pmbus_data *data,
877 					     const char *name, const char *type,
878 					     int seq, int page, int reg,
879 					     enum pmbus_sensor_classes class,
880 					     bool update, bool readonly)
881 {
882 	struct pmbus_sensor *sensor;
883 	struct device_attribute *a;
884 
885 	sensor = devm_kzalloc(data->dev, sizeof(*sensor), GFP_KERNEL);
886 	if (!sensor)
887 		return NULL;
888 	a = &sensor->attribute;
889 
890 	snprintf(sensor->name, sizeof(sensor->name), "%s%d_%s",
891 		 name, seq, type);
892 	sensor->page = page;
893 	sensor->reg = reg;
894 	sensor->class = class;
895 	sensor->update = update;
896 	pmbus_dev_attr_init(a, sensor->name,
897 			    readonly ? S_IRUGO : S_IRUGO | S_IWUSR,
898 			    pmbus_show_sensor, pmbus_set_sensor);
899 
900 	if (pmbus_add_attribute(data, &a->attr))
901 		return NULL;
902 
903 	sensor->next = data->sensors;
904 	data->sensors = sensor;
905 
906 	return sensor;
907 }
908 
909 static int pmbus_add_label(struct pmbus_data *data,
910 			   const char *name, int seq,
911 			   const char *lstring, int index)
912 {
913 	struct pmbus_label *label;
914 	struct device_attribute *a;
915 
916 	label = devm_kzalloc(data->dev, sizeof(*label), GFP_KERNEL);
917 	if (!label)
918 		return -ENOMEM;
919 
920 	a = &label->attribute;
921 
922 	snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
923 	if (!index)
924 		strncpy(label->label, lstring, sizeof(label->label) - 1);
925 	else
926 		snprintf(label->label, sizeof(label->label), "%s%d", lstring,
927 			 index);
928 
929 	pmbus_dev_attr_init(a, label->name, S_IRUGO, pmbus_show_label, NULL);
930 	return pmbus_add_attribute(data, &a->attr);
931 }
932 
933 /*
934  * Search for attributes. Allocate sensors, booleans, and labels as needed.
935  */
936 
937 /*
938  * The pmbus_limit_attr structure describes a single limit attribute
939  * and its associated alarm attribute.
940  */
941 struct pmbus_limit_attr {
942 	u16 reg;		/* Limit register */
943 	u16 sbit;		/* Alarm attribute status bit */
944 	bool update;		/* True if register needs updates */
945 	bool low;		/* True if low limit; for limits with compare
946 				   functions only */
947 	const char *attr;	/* Attribute name */
948 	const char *alarm;	/* Alarm attribute name */
949 };
950 
951 /*
952  * The pmbus_sensor_attr structure describes one sensor attribute. This
953  * description includes a reference to the associated limit attributes.
954  */
955 struct pmbus_sensor_attr {
956 	u16 reg;			/* sensor register */
957 	u8 gbit;			/* generic status bit */
958 	u8 nlimit;			/* # of limit registers */
959 	enum pmbus_sensor_classes class;/* sensor class */
960 	const char *label;		/* sensor label */
961 	bool paged;			/* true if paged sensor */
962 	bool update;			/* true if update needed */
963 	bool compare;			/* true if compare function needed */
964 	u32 func;			/* sensor mask */
965 	u32 sfunc;			/* sensor status mask */
966 	int sbase;			/* status base register */
967 	const struct pmbus_limit_attr *limit;/* limit registers */
968 };
969 
970 /*
971  * Add a set of limit attributes and, if supported, the associated
972  * alarm attributes.
973  * returns 0 if no alarm register found, 1 if an alarm register was found,
974  * < 0 on errors.
975  */
976 static int pmbus_add_limit_attrs(struct i2c_client *client,
977 				 struct pmbus_data *data,
978 				 const struct pmbus_driver_info *info,
979 				 const char *name, int index, int page,
980 				 struct pmbus_sensor *base,
981 				 const struct pmbus_sensor_attr *attr)
982 {
983 	const struct pmbus_limit_attr *l = attr->limit;
984 	int nlimit = attr->nlimit;
985 	int have_alarm = 0;
986 	int i, ret;
987 	struct pmbus_sensor *curr;
988 
989 	for (i = 0; i < nlimit; i++) {
990 		if (pmbus_check_word_register(client, page, l->reg)) {
991 			curr = pmbus_add_sensor(data, name, l->attr, index,
992 						page, l->reg, attr->class,
993 						attr->update || l->update,
994 						false);
995 			if (!curr)
996 				return -ENOMEM;
997 			if (l->sbit && (info->func[page] & attr->sfunc)) {
998 				ret = pmbus_add_boolean(data, name,
999 					l->alarm, index,
1000 					attr->compare ?  l->low ? curr : base
1001 						      : NULL,
1002 					attr->compare ? l->low ? base : curr
1003 						      : NULL,
1004 					attr->sbase + page, l->sbit);
1005 				if (ret)
1006 					return ret;
1007 				have_alarm = 1;
1008 			}
1009 		}
1010 		l++;
1011 	}
1012 	return have_alarm;
1013 }
1014 
1015 static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
1016 				      struct pmbus_data *data,
1017 				      const struct pmbus_driver_info *info,
1018 				      const char *name,
1019 				      int index, int page,
1020 				      const struct pmbus_sensor_attr *attr)
1021 {
1022 	struct pmbus_sensor *base;
1023 	int ret;
1024 
1025 	if (attr->label) {
1026 		ret = pmbus_add_label(data, name, index, attr->label,
1027 				      attr->paged ? page + 1 : 0);
1028 		if (ret)
1029 			return ret;
1030 	}
1031 	base = pmbus_add_sensor(data, name, "input", index, page, attr->reg,
1032 				attr->class, true, true);
1033 	if (!base)
1034 		return -ENOMEM;
1035 	if (attr->sfunc) {
1036 		ret = pmbus_add_limit_attrs(client, data, info, name,
1037 					    index, page, base, attr);
1038 		if (ret < 0)
1039 			return ret;
1040 		/*
1041 		 * Add generic alarm attribute only if there are no individual
1042 		 * alarm attributes, if there is a global alarm bit, and if
1043 		 * the generic status register for this page is accessible.
1044 		 */
1045 		if (!ret && attr->gbit &&
1046 		    pmbus_check_byte_register(client, page,
1047 					      data->status_register)) {
1048 			ret = pmbus_add_boolean(data, name, "alarm", index,
1049 						NULL, NULL,
1050 						PB_STATUS_BASE + page,
1051 						attr->gbit);
1052 			if (ret)
1053 				return ret;
1054 		}
1055 	}
1056 	return 0;
1057 }
1058 
1059 static int pmbus_add_sensor_attrs(struct i2c_client *client,
1060 				  struct pmbus_data *data,
1061 				  const char *name,
1062 				  const struct pmbus_sensor_attr *attrs,
1063 				  int nattrs)
1064 {
1065 	const struct pmbus_driver_info *info = data->info;
1066 	int index, i;
1067 	int ret;
1068 
1069 	index = 1;
1070 	for (i = 0; i < nattrs; i++) {
1071 		int page, pages;
1072 
1073 		pages = attrs->paged ? info->pages : 1;
1074 		for (page = 0; page < pages; page++) {
1075 			if (!(info->func[page] & attrs->func))
1076 				continue;
1077 			ret = pmbus_add_sensor_attrs_one(client, data, info,
1078 							 name, index, page,
1079 							 attrs);
1080 			if (ret)
1081 				return ret;
1082 			index++;
1083 		}
1084 		attrs++;
1085 	}
1086 	return 0;
1087 }
1088 
1089 static const struct pmbus_limit_attr vin_limit_attrs[] = {
1090 	{
1091 		.reg = PMBUS_VIN_UV_WARN_LIMIT,
1092 		.attr = "min",
1093 		.alarm = "min_alarm",
1094 		.sbit = PB_VOLTAGE_UV_WARNING,
1095 	}, {
1096 		.reg = PMBUS_VIN_UV_FAULT_LIMIT,
1097 		.attr = "lcrit",
1098 		.alarm = "lcrit_alarm",
1099 		.sbit = PB_VOLTAGE_UV_FAULT,
1100 	}, {
1101 		.reg = PMBUS_VIN_OV_WARN_LIMIT,
1102 		.attr = "max",
1103 		.alarm = "max_alarm",
1104 		.sbit = PB_VOLTAGE_OV_WARNING,
1105 	}, {
1106 		.reg = PMBUS_VIN_OV_FAULT_LIMIT,
1107 		.attr = "crit",
1108 		.alarm = "crit_alarm",
1109 		.sbit = PB_VOLTAGE_OV_FAULT,
1110 	}, {
1111 		.reg = PMBUS_VIRT_READ_VIN_AVG,
1112 		.update = true,
1113 		.attr = "average",
1114 	}, {
1115 		.reg = PMBUS_VIRT_READ_VIN_MIN,
1116 		.update = true,
1117 		.attr = "lowest",
1118 	}, {
1119 		.reg = PMBUS_VIRT_READ_VIN_MAX,
1120 		.update = true,
1121 		.attr = "highest",
1122 	}, {
1123 		.reg = PMBUS_VIRT_RESET_VIN_HISTORY,
1124 		.attr = "reset_history",
1125 	},
1126 };
1127 
1128 static const struct pmbus_limit_attr vmon_limit_attrs[] = {
1129 	{
1130 		.reg = PMBUS_VIRT_VMON_UV_WARN_LIMIT,
1131 		.attr = "min",
1132 		.alarm = "min_alarm",
1133 		.sbit = PB_VOLTAGE_UV_WARNING,
1134 	}, {
1135 		.reg = PMBUS_VIRT_VMON_UV_FAULT_LIMIT,
1136 		.attr = "lcrit",
1137 		.alarm = "lcrit_alarm",
1138 		.sbit = PB_VOLTAGE_UV_FAULT,
1139 	}, {
1140 		.reg = PMBUS_VIRT_VMON_OV_WARN_LIMIT,
1141 		.attr = "max",
1142 		.alarm = "max_alarm",
1143 		.sbit = PB_VOLTAGE_OV_WARNING,
1144 	}, {
1145 		.reg = PMBUS_VIRT_VMON_OV_FAULT_LIMIT,
1146 		.attr = "crit",
1147 		.alarm = "crit_alarm",
1148 		.sbit = PB_VOLTAGE_OV_FAULT,
1149 	}
1150 };
1151 
1152 static const struct pmbus_limit_attr vout_limit_attrs[] = {
1153 	{
1154 		.reg = PMBUS_VOUT_UV_WARN_LIMIT,
1155 		.attr = "min",
1156 		.alarm = "min_alarm",
1157 		.sbit = PB_VOLTAGE_UV_WARNING,
1158 	}, {
1159 		.reg = PMBUS_VOUT_UV_FAULT_LIMIT,
1160 		.attr = "lcrit",
1161 		.alarm = "lcrit_alarm",
1162 		.sbit = PB_VOLTAGE_UV_FAULT,
1163 	}, {
1164 		.reg = PMBUS_VOUT_OV_WARN_LIMIT,
1165 		.attr = "max",
1166 		.alarm = "max_alarm",
1167 		.sbit = PB_VOLTAGE_OV_WARNING,
1168 	}, {
1169 		.reg = PMBUS_VOUT_OV_FAULT_LIMIT,
1170 		.attr = "crit",
1171 		.alarm = "crit_alarm",
1172 		.sbit = PB_VOLTAGE_OV_FAULT,
1173 	}, {
1174 		.reg = PMBUS_VIRT_READ_VOUT_AVG,
1175 		.update = true,
1176 		.attr = "average",
1177 	}, {
1178 		.reg = PMBUS_VIRT_READ_VOUT_MIN,
1179 		.update = true,
1180 		.attr = "lowest",
1181 	}, {
1182 		.reg = PMBUS_VIRT_READ_VOUT_MAX,
1183 		.update = true,
1184 		.attr = "highest",
1185 	}, {
1186 		.reg = PMBUS_VIRT_RESET_VOUT_HISTORY,
1187 		.attr = "reset_history",
1188 	}
1189 };
1190 
1191 static const struct pmbus_sensor_attr voltage_attributes[] = {
1192 	{
1193 		.reg = PMBUS_READ_VIN,
1194 		.class = PSC_VOLTAGE_IN,
1195 		.label = "vin",
1196 		.func = PMBUS_HAVE_VIN,
1197 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1198 		.sbase = PB_STATUS_INPUT_BASE,
1199 		.gbit = PB_STATUS_VIN_UV,
1200 		.limit = vin_limit_attrs,
1201 		.nlimit = ARRAY_SIZE(vin_limit_attrs),
1202 	}, {
1203 		.reg = PMBUS_VIRT_READ_VMON,
1204 		.class = PSC_VOLTAGE_IN,
1205 		.label = "vmon",
1206 		.func = PMBUS_HAVE_VMON,
1207 		.sfunc = PMBUS_HAVE_STATUS_VMON,
1208 		.sbase = PB_STATUS_VMON_BASE,
1209 		.limit = vmon_limit_attrs,
1210 		.nlimit = ARRAY_SIZE(vmon_limit_attrs),
1211 	}, {
1212 		.reg = PMBUS_READ_VCAP,
1213 		.class = PSC_VOLTAGE_IN,
1214 		.label = "vcap",
1215 		.func = PMBUS_HAVE_VCAP,
1216 	}, {
1217 		.reg = PMBUS_READ_VOUT,
1218 		.class = PSC_VOLTAGE_OUT,
1219 		.label = "vout",
1220 		.paged = true,
1221 		.func = PMBUS_HAVE_VOUT,
1222 		.sfunc = PMBUS_HAVE_STATUS_VOUT,
1223 		.sbase = PB_STATUS_VOUT_BASE,
1224 		.gbit = PB_STATUS_VOUT_OV,
1225 		.limit = vout_limit_attrs,
1226 		.nlimit = ARRAY_SIZE(vout_limit_attrs),
1227 	}
1228 };
1229 
1230 /* Current attributes */
1231 
1232 static const struct pmbus_limit_attr iin_limit_attrs[] = {
1233 	{
1234 		.reg = PMBUS_IIN_OC_WARN_LIMIT,
1235 		.attr = "max",
1236 		.alarm = "max_alarm",
1237 		.sbit = PB_IIN_OC_WARNING,
1238 	}, {
1239 		.reg = PMBUS_IIN_OC_FAULT_LIMIT,
1240 		.attr = "crit",
1241 		.alarm = "crit_alarm",
1242 		.sbit = PB_IIN_OC_FAULT,
1243 	}, {
1244 		.reg = PMBUS_VIRT_READ_IIN_AVG,
1245 		.update = true,
1246 		.attr = "average",
1247 	}, {
1248 		.reg = PMBUS_VIRT_READ_IIN_MIN,
1249 		.update = true,
1250 		.attr = "lowest",
1251 	}, {
1252 		.reg = PMBUS_VIRT_READ_IIN_MAX,
1253 		.update = true,
1254 		.attr = "highest",
1255 	}, {
1256 		.reg = PMBUS_VIRT_RESET_IIN_HISTORY,
1257 		.attr = "reset_history",
1258 	}
1259 };
1260 
1261 static const struct pmbus_limit_attr iout_limit_attrs[] = {
1262 	{
1263 		.reg = PMBUS_IOUT_OC_WARN_LIMIT,
1264 		.attr = "max",
1265 		.alarm = "max_alarm",
1266 		.sbit = PB_IOUT_OC_WARNING,
1267 	}, {
1268 		.reg = PMBUS_IOUT_UC_FAULT_LIMIT,
1269 		.attr = "lcrit",
1270 		.alarm = "lcrit_alarm",
1271 		.sbit = PB_IOUT_UC_FAULT,
1272 	}, {
1273 		.reg = PMBUS_IOUT_OC_FAULT_LIMIT,
1274 		.attr = "crit",
1275 		.alarm = "crit_alarm",
1276 		.sbit = PB_IOUT_OC_FAULT,
1277 	}, {
1278 		.reg = PMBUS_VIRT_READ_IOUT_AVG,
1279 		.update = true,
1280 		.attr = "average",
1281 	}, {
1282 		.reg = PMBUS_VIRT_READ_IOUT_MIN,
1283 		.update = true,
1284 		.attr = "lowest",
1285 	}, {
1286 		.reg = PMBUS_VIRT_READ_IOUT_MAX,
1287 		.update = true,
1288 		.attr = "highest",
1289 	}, {
1290 		.reg = PMBUS_VIRT_RESET_IOUT_HISTORY,
1291 		.attr = "reset_history",
1292 	}
1293 };
1294 
1295 static const struct pmbus_sensor_attr current_attributes[] = {
1296 	{
1297 		.reg = PMBUS_READ_IIN,
1298 		.class = PSC_CURRENT_IN,
1299 		.label = "iin",
1300 		.func = PMBUS_HAVE_IIN,
1301 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1302 		.sbase = PB_STATUS_INPUT_BASE,
1303 		.limit = iin_limit_attrs,
1304 		.nlimit = ARRAY_SIZE(iin_limit_attrs),
1305 	}, {
1306 		.reg = PMBUS_READ_IOUT,
1307 		.class = PSC_CURRENT_OUT,
1308 		.label = "iout",
1309 		.paged = true,
1310 		.func = PMBUS_HAVE_IOUT,
1311 		.sfunc = PMBUS_HAVE_STATUS_IOUT,
1312 		.sbase = PB_STATUS_IOUT_BASE,
1313 		.gbit = PB_STATUS_IOUT_OC,
1314 		.limit = iout_limit_attrs,
1315 		.nlimit = ARRAY_SIZE(iout_limit_attrs),
1316 	}
1317 };
1318 
1319 /* Power attributes */
1320 
1321 static const struct pmbus_limit_attr pin_limit_attrs[] = {
1322 	{
1323 		.reg = PMBUS_PIN_OP_WARN_LIMIT,
1324 		.attr = "max",
1325 		.alarm = "alarm",
1326 		.sbit = PB_PIN_OP_WARNING,
1327 	}, {
1328 		.reg = PMBUS_VIRT_READ_PIN_AVG,
1329 		.update = true,
1330 		.attr = "average",
1331 	}, {
1332 		.reg = PMBUS_VIRT_READ_PIN_MAX,
1333 		.update = true,
1334 		.attr = "input_highest",
1335 	}, {
1336 		.reg = PMBUS_VIRT_RESET_PIN_HISTORY,
1337 		.attr = "reset_history",
1338 	}
1339 };
1340 
1341 static const struct pmbus_limit_attr pout_limit_attrs[] = {
1342 	{
1343 		.reg = PMBUS_POUT_MAX,
1344 		.attr = "cap",
1345 		.alarm = "cap_alarm",
1346 		.sbit = PB_POWER_LIMITING,
1347 	}, {
1348 		.reg = PMBUS_POUT_OP_WARN_LIMIT,
1349 		.attr = "max",
1350 		.alarm = "max_alarm",
1351 		.sbit = PB_POUT_OP_WARNING,
1352 	}, {
1353 		.reg = PMBUS_POUT_OP_FAULT_LIMIT,
1354 		.attr = "crit",
1355 		.alarm = "crit_alarm",
1356 		.sbit = PB_POUT_OP_FAULT,
1357 	}, {
1358 		.reg = PMBUS_VIRT_READ_POUT_AVG,
1359 		.update = true,
1360 		.attr = "average",
1361 	}, {
1362 		.reg = PMBUS_VIRT_READ_POUT_MAX,
1363 		.update = true,
1364 		.attr = "input_highest",
1365 	}, {
1366 		.reg = PMBUS_VIRT_RESET_POUT_HISTORY,
1367 		.attr = "reset_history",
1368 	}
1369 };
1370 
1371 static const struct pmbus_sensor_attr power_attributes[] = {
1372 	{
1373 		.reg = PMBUS_READ_PIN,
1374 		.class = PSC_POWER,
1375 		.label = "pin",
1376 		.func = PMBUS_HAVE_PIN,
1377 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1378 		.sbase = PB_STATUS_INPUT_BASE,
1379 		.limit = pin_limit_attrs,
1380 		.nlimit = ARRAY_SIZE(pin_limit_attrs),
1381 	}, {
1382 		.reg = PMBUS_READ_POUT,
1383 		.class = PSC_POWER,
1384 		.label = "pout",
1385 		.paged = true,
1386 		.func = PMBUS_HAVE_POUT,
1387 		.sfunc = PMBUS_HAVE_STATUS_IOUT,
1388 		.sbase = PB_STATUS_IOUT_BASE,
1389 		.limit = pout_limit_attrs,
1390 		.nlimit = ARRAY_SIZE(pout_limit_attrs),
1391 	}
1392 };
1393 
1394 /* Temperature atributes */
1395 
1396 static const struct pmbus_limit_attr temp_limit_attrs[] = {
1397 	{
1398 		.reg = PMBUS_UT_WARN_LIMIT,
1399 		.low = true,
1400 		.attr = "min",
1401 		.alarm = "min_alarm",
1402 		.sbit = PB_TEMP_UT_WARNING,
1403 	}, {
1404 		.reg = PMBUS_UT_FAULT_LIMIT,
1405 		.low = true,
1406 		.attr = "lcrit",
1407 		.alarm = "lcrit_alarm",
1408 		.sbit = PB_TEMP_UT_FAULT,
1409 	}, {
1410 		.reg = PMBUS_OT_WARN_LIMIT,
1411 		.attr = "max",
1412 		.alarm = "max_alarm",
1413 		.sbit = PB_TEMP_OT_WARNING,
1414 	}, {
1415 		.reg = PMBUS_OT_FAULT_LIMIT,
1416 		.attr = "crit",
1417 		.alarm = "crit_alarm",
1418 		.sbit = PB_TEMP_OT_FAULT,
1419 	}, {
1420 		.reg = PMBUS_VIRT_READ_TEMP_MIN,
1421 		.attr = "lowest",
1422 	}, {
1423 		.reg = PMBUS_VIRT_READ_TEMP_AVG,
1424 		.attr = "average",
1425 	}, {
1426 		.reg = PMBUS_VIRT_READ_TEMP_MAX,
1427 		.attr = "highest",
1428 	}, {
1429 		.reg = PMBUS_VIRT_RESET_TEMP_HISTORY,
1430 		.attr = "reset_history",
1431 	}
1432 };
1433 
1434 static const struct pmbus_limit_attr temp_limit_attrs2[] = {
1435 	{
1436 		.reg = PMBUS_UT_WARN_LIMIT,
1437 		.low = true,
1438 		.attr = "min",
1439 		.alarm = "min_alarm",
1440 		.sbit = PB_TEMP_UT_WARNING,
1441 	}, {
1442 		.reg = PMBUS_UT_FAULT_LIMIT,
1443 		.low = true,
1444 		.attr = "lcrit",
1445 		.alarm = "lcrit_alarm",
1446 		.sbit = PB_TEMP_UT_FAULT,
1447 	}, {
1448 		.reg = PMBUS_OT_WARN_LIMIT,
1449 		.attr = "max",
1450 		.alarm = "max_alarm",
1451 		.sbit = PB_TEMP_OT_WARNING,
1452 	}, {
1453 		.reg = PMBUS_OT_FAULT_LIMIT,
1454 		.attr = "crit",
1455 		.alarm = "crit_alarm",
1456 		.sbit = PB_TEMP_OT_FAULT,
1457 	}, {
1458 		.reg = PMBUS_VIRT_READ_TEMP2_MIN,
1459 		.attr = "lowest",
1460 	}, {
1461 		.reg = PMBUS_VIRT_READ_TEMP2_AVG,
1462 		.attr = "average",
1463 	}, {
1464 		.reg = PMBUS_VIRT_READ_TEMP2_MAX,
1465 		.attr = "highest",
1466 	}, {
1467 		.reg = PMBUS_VIRT_RESET_TEMP2_HISTORY,
1468 		.attr = "reset_history",
1469 	}
1470 };
1471 
1472 static const struct pmbus_limit_attr temp_limit_attrs3[] = {
1473 	{
1474 		.reg = PMBUS_UT_WARN_LIMIT,
1475 		.low = true,
1476 		.attr = "min",
1477 		.alarm = "min_alarm",
1478 		.sbit = PB_TEMP_UT_WARNING,
1479 	}, {
1480 		.reg = PMBUS_UT_FAULT_LIMIT,
1481 		.low = true,
1482 		.attr = "lcrit",
1483 		.alarm = "lcrit_alarm",
1484 		.sbit = PB_TEMP_UT_FAULT,
1485 	}, {
1486 		.reg = PMBUS_OT_WARN_LIMIT,
1487 		.attr = "max",
1488 		.alarm = "max_alarm",
1489 		.sbit = PB_TEMP_OT_WARNING,
1490 	}, {
1491 		.reg = PMBUS_OT_FAULT_LIMIT,
1492 		.attr = "crit",
1493 		.alarm = "crit_alarm",
1494 		.sbit = PB_TEMP_OT_FAULT,
1495 	}
1496 };
1497 
1498 static const struct pmbus_sensor_attr temp_attributes[] = {
1499 	{
1500 		.reg = PMBUS_READ_TEMPERATURE_1,
1501 		.class = PSC_TEMPERATURE,
1502 		.paged = true,
1503 		.update = true,
1504 		.compare = true,
1505 		.func = PMBUS_HAVE_TEMP,
1506 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1507 		.sbase = PB_STATUS_TEMP_BASE,
1508 		.gbit = PB_STATUS_TEMPERATURE,
1509 		.limit = temp_limit_attrs,
1510 		.nlimit = ARRAY_SIZE(temp_limit_attrs),
1511 	}, {
1512 		.reg = PMBUS_READ_TEMPERATURE_2,
1513 		.class = PSC_TEMPERATURE,
1514 		.paged = true,
1515 		.update = true,
1516 		.compare = true,
1517 		.func = PMBUS_HAVE_TEMP2,
1518 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1519 		.sbase = PB_STATUS_TEMP_BASE,
1520 		.gbit = PB_STATUS_TEMPERATURE,
1521 		.limit = temp_limit_attrs2,
1522 		.nlimit = ARRAY_SIZE(temp_limit_attrs2),
1523 	}, {
1524 		.reg = PMBUS_READ_TEMPERATURE_3,
1525 		.class = PSC_TEMPERATURE,
1526 		.paged = true,
1527 		.update = true,
1528 		.compare = true,
1529 		.func = PMBUS_HAVE_TEMP3,
1530 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1531 		.sbase = PB_STATUS_TEMP_BASE,
1532 		.gbit = PB_STATUS_TEMPERATURE,
1533 		.limit = temp_limit_attrs3,
1534 		.nlimit = ARRAY_SIZE(temp_limit_attrs3),
1535 	}
1536 };
1537 
1538 static const int pmbus_fan_registers[] = {
1539 	PMBUS_READ_FAN_SPEED_1,
1540 	PMBUS_READ_FAN_SPEED_2,
1541 	PMBUS_READ_FAN_SPEED_3,
1542 	PMBUS_READ_FAN_SPEED_4
1543 };
1544 
1545 static const int pmbus_fan_config_registers[] = {
1546 	PMBUS_FAN_CONFIG_12,
1547 	PMBUS_FAN_CONFIG_12,
1548 	PMBUS_FAN_CONFIG_34,
1549 	PMBUS_FAN_CONFIG_34
1550 };
1551 
1552 static const int pmbus_fan_status_registers[] = {
1553 	PMBUS_STATUS_FAN_12,
1554 	PMBUS_STATUS_FAN_12,
1555 	PMBUS_STATUS_FAN_34,
1556 	PMBUS_STATUS_FAN_34
1557 };
1558 
1559 static const u32 pmbus_fan_flags[] = {
1560 	PMBUS_HAVE_FAN12,
1561 	PMBUS_HAVE_FAN12,
1562 	PMBUS_HAVE_FAN34,
1563 	PMBUS_HAVE_FAN34
1564 };
1565 
1566 static const u32 pmbus_fan_status_flags[] = {
1567 	PMBUS_HAVE_STATUS_FAN12,
1568 	PMBUS_HAVE_STATUS_FAN12,
1569 	PMBUS_HAVE_STATUS_FAN34,
1570 	PMBUS_HAVE_STATUS_FAN34
1571 };
1572 
1573 /* Fans */
1574 static int pmbus_add_fan_attributes(struct i2c_client *client,
1575 				    struct pmbus_data *data)
1576 {
1577 	const struct pmbus_driver_info *info = data->info;
1578 	int index = 1;
1579 	int page;
1580 	int ret;
1581 
1582 	for (page = 0; page < info->pages; page++) {
1583 		int f;
1584 
1585 		for (f = 0; f < ARRAY_SIZE(pmbus_fan_registers); f++) {
1586 			int regval;
1587 
1588 			if (!(info->func[page] & pmbus_fan_flags[f]))
1589 				break;
1590 
1591 			if (!pmbus_check_word_register(client, page,
1592 						       pmbus_fan_registers[f]))
1593 				break;
1594 
1595 			/*
1596 			 * Skip fan if not installed.
1597 			 * Each fan configuration register covers multiple fans,
1598 			 * so we have to do some magic.
1599 			 */
1600 			regval = _pmbus_read_byte_data(client, page,
1601 				pmbus_fan_config_registers[f]);
1602 			if (regval < 0 ||
1603 			    (!(regval & (PB_FAN_1_INSTALLED >> ((f & 1) * 4)))))
1604 				continue;
1605 
1606 			if (pmbus_add_sensor(data, "fan", "input", index,
1607 					     page, pmbus_fan_registers[f],
1608 					     PSC_FAN, true, true) == NULL)
1609 				return -ENOMEM;
1610 
1611 			/*
1612 			 * Each fan status register covers multiple fans,
1613 			 * so we have to do some magic.
1614 			 */
1615 			if ((info->func[page] & pmbus_fan_status_flags[f]) &&
1616 			    pmbus_check_byte_register(client,
1617 					page, pmbus_fan_status_registers[f])) {
1618 				int base;
1619 
1620 				if (f > 1)	/* fan 3, 4 */
1621 					base = PB_STATUS_FAN34_BASE + page;
1622 				else
1623 					base = PB_STATUS_FAN_BASE + page;
1624 				ret = pmbus_add_boolean(data, "fan",
1625 					"alarm", index, NULL, NULL, base,
1626 					PB_FAN_FAN1_WARNING >> (f & 1));
1627 				if (ret)
1628 					return ret;
1629 				ret = pmbus_add_boolean(data, "fan",
1630 					"fault", index, NULL, NULL, base,
1631 					PB_FAN_FAN1_FAULT >> (f & 1));
1632 				if (ret)
1633 					return ret;
1634 			}
1635 			index++;
1636 		}
1637 	}
1638 	return 0;
1639 }
1640 
1641 static int pmbus_find_attributes(struct i2c_client *client,
1642 				 struct pmbus_data *data)
1643 {
1644 	int ret;
1645 
1646 	/* Voltage sensors */
1647 	ret = pmbus_add_sensor_attrs(client, data, "in", voltage_attributes,
1648 				     ARRAY_SIZE(voltage_attributes));
1649 	if (ret)
1650 		return ret;
1651 
1652 	/* Current sensors */
1653 	ret = pmbus_add_sensor_attrs(client, data, "curr", current_attributes,
1654 				     ARRAY_SIZE(current_attributes));
1655 	if (ret)
1656 		return ret;
1657 
1658 	/* Power sensors */
1659 	ret = pmbus_add_sensor_attrs(client, data, "power", power_attributes,
1660 				     ARRAY_SIZE(power_attributes));
1661 	if (ret)
1662 		return ret;
1663 
1664 	/* Temperature sensors */
1665 	ret = pmbus_add_sensor_attrs(client, data, "temp", temp_attributes,
1666 				     ARRAY_SIZE(temp_attributes));
1667 	if (ret)
1668 		return ret;
1669 
1670 	/* Fans */
1671 	ret = pmbus_add_fan_attributes(client, data);
1672 	return ret;
1673 }
1674 
1675 /*
1676  * Identify chip parameters.
1677  * This function is called for all chips.
1678  */
1679 static int pmbus_identify_common(struct i2c_client *client,
1680 				 struct pmbus_data *data, int page)
1681 {
1682 	int vout_mode = -1;
1683 
1684 	if (pmbus_check_byte_register(client, page, PMBUS_VOUT_MODE))
1685 		vout_mode = _pmbus_read_byte_data(client, page,
1686 						  PMBUS_VOUT_MODE);
1687 	if (vout_mode >= 0 && vout_mode != 0xff) {
1688 		/*
1689 		 * Not all chips support the VOUT_MODE command,
1690 		 * so a failure to read it is not an error.
1691 		 */
1692 		switch (vout_mode >> 5) {
1693 		case 0:	/* linear mode      */
1694 			if (data->info->format[PSC_VOLTAGE_OUT] != linear)
1695 				return -ENODEV;
1696 
1697 			data->exponent[page] = ((s8)(vout_mode << 3)) >> 3;
1698 			break;
1699 		case 1: /* VID mode         */
1700 			if (data->info->format[PSC_VOLTAGE_OUT] != vid)
1701 				return -ENODEV;
1702 			break;
1703 		case 2:	/* direct mode      */
1704 			if (data->info->format[PSC_VOLTAGE_OUT] != direct)
1705 				return -ENODEV;
1706 			break;
1707 		default:
1708 			return -ENODEV;
1709 		}
1710 	}
1711 
1712 	pmbus_clear_fault_page(client, page);
1713 	return 0;
1714 }
1715 
1716 static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data,
1717 			     struct pmbus_driver_info *info)
1718 {
1719 	struct device *dev = &client->dev;
1720 	int page, ret;
1721 
1722 	/*
1723 	 * Some PMBus chips don't support PMBUS_STATUS_BYTE, so try
1724 	 * to use PMBUS_STATUS_WORD instead if that is the case.
1725 	 * Bail out if both registers are not supported.
1726 	 */
1727 	data->status_register = PMBUS_STATUS_BYTE;
1728 	ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE);
1729 	if (ret < 0 || ret == 0xff) {
1730 		data->status_register = PMBUS_STATUS_WORD;
1731 		ret = i2c_smbus_read_word_data(client, PMBUS_STATUS_WORD);
1732 		if (ret < 0 || ret == 0xffff) {
1733 			dev_err(dev, "PMBus status register not found\n");
1734 			return -ENODEV;
1735 		}
1736 	}
1737 
1738 	pmbus_clear_faults(client);
1739 
1740 	if (info->identify) {
1741 		ret = (*info->identify)(client, info);
1742 		if (ret < 0) {
1743 			dev_err(dev, "Chip identification failed\n");
1744 			return ret;
1745 		}
1746 	}
1747 
1748 	if (info->pages <= 0 || info->pages > PMBUS_PAGES) {
1749 		dev_err(dev, "Bad number of PMBus pages: %d\n", info->pages);
1750 		return -ENODEV;
1751 	}
1752 
1753 	for (page = 0; page < info->pages; page++) {
1754 		ret = pmbus_identify_common(client, data, page);
1755 		if (ret < 0) {
1756 			dev_err(dev, "Failed to identify chip capabilities\n");
1757 			return ret;
1758 		}
1759 	}
1760 	return 0;
1761 }
1762 
1763 #if IS_ENABLED(CONFIG_REGULATOR)
1764 static int pmbus_regulator_is_enabled(struct regulator_dev *rdev)
1765 {
1766 	struct device *dev = rdev_get_dev(rdev);
1767 	struct i2c_client *client = to_i2c_client(dev->parent);
1768 	u8 page = rdev_get_id(rdev);
1769 	int ret;
1770 
1771 	ret = pmbus_read_byte_data(client, page, PMBUS_OPERATION);
1772 	if (ret < 0)
1773 		return ret;
1774 
1775 	return !!(ret & PB_OPERATION_CONTROL_ON);
1776 }
1777 
1778 static int _pmbus_regulator_on_off(struct regulator_dev *rdev, bool enable)
1779 {
1780 	struct device *dev = rdev_get_dev(rdev);
1781 	struct i2c_client *client = to_i2c_client(dev->parent);
1782 	u8 page = rdev_get_id(rdev);
1783 
1784 	return pmbus_update_byte_data(client, page, PMBUS_OPERATION,
1785 				      PB_OPERATION_CONTROL_ON,
1786 				      enable ? PB_OPERATION_CONTROL_ON : 0);
1787 }
1788 
1789 static int pmbus_regulator_enable(struct regulator_dev *rdev)
1790 {
1791 	return _pmbus_regulator_on_off(rdev, 1);
1792 }
1793 
1794 static int pmbus_regulator_disable(struct regulator_dev *rdev)
1795 {
1796 	return _pmbus_regulator_on_off(rdev, 0);
1797 }
1798 
1799 struct regulator_ops pmbus_regulator_ops = {
1800 	.enable = pmbus_regulator_enable,
1801 	.disable = pmbus_regulator_disable,
1802 	.is_enabled = pmbus_regulator_is_enabled,
1803 };
1804 EXPORT_SYMBOL_GPL(pmbus_regulator_ops);
1805 
1806 static int pmbus_regulator_register(struct pmbus_data *data)
1807 {
1808 	struct device *dev = data->dev;
1809 	const struct pmbus_driver_info *info = data->info;
1810 	const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
1811 	struct regulator_dev *rdev;
1812 	int i;
1813 
1814 	for (i = 0; i < info->num_regulators; i++) {
1815 		struct regulator_config config = { };
1816 
1817 		config.dev = dev;
1818 		config.driver_data = data;
1819 
1820 		if (pdata && pdata->reg_init_data)
1821 			config.init_data = &pdata->reg_init_data[i];
1822 
1823 		rdev = devm_regulator_register(dev, &info->reg_desc[i],
1824 					       &config);
1825 		if (IS_ERR(rdev)) {
1826 			dev_err(dev, "Failed to register %s regulator\n",
1827 				info->reg_desc[i].name);
1828 			return PTR_ERR(rdev);
1829 		}
1830 	}
1831 
1832 	return 0;
1833 }
1834 #else
1835 static int pmbus_regulator_register(struct pmbus_data *data)
1836 {
1837 	return 0;
1838 }
1839 #endif
1840 
1841 int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
1842 		   struct pmbus_driver_info *info)
1843 {
1844 	struct device *dev = &client->dev;
1845 	const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
1846 	struct pmbus_data *data;
1847 	int ret;
1848 
1849 	if (!info)
1850 		return -ENODEV;
1851 
1852 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE
1853 				     | I2C_FUNC_SMBUS_BYTE_DATA
1854 				     | I2C_FUNC_SMBUS_WORD_DATA))
1855 		return -ENODEV;
1856 
1857 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
1858 	if (!data)
1859 		return -ENOMEM;
1860 
1861 	i2c_set_clientdata(client, data);
1862 	mutex_init(&data->update_lock);
1863 	data->dev = dev;
1864 
1865 	if (pdata)
1866 		data->flags = pdata->flags;
1867 	data->info = info;
1868 
1869 	ret = pmbus_init_common(client, data, info);
1870 	if (ret < 0)
1871 		return ret;
1872 
1873 	ret = pmbus_find_attributes(client, data);
1874 	if (ret)
1875 		goto out_kfree;
1876 
1877 	/*
1878 	 * If there are no attributes, something is wrong.
1879 	 * Bail out instead of trying to register nothing.
1880 	 */
1881 	if (!data->num_attributes) {
1882 		dev_err(dev, "No attributes found\n");
1883 		ret = -ENODEV;
1884 		goto out_kfree;
1885 	}
1886 
1887 	data->groups[0] = &data->group;
1888 	data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
1889 							    data, data->groups);
1890 	if (IS_ERR(data->hwmon_dev)) {
1891 		ret = PTR_ERR(data->hwmon_dev);
1892 		dev_err(dev, "Failed to register hwmon device\n");
1893 		goto out_kfree;
1894 	}
1895 
1896 	ret = pmbus_regulator_register(data);
1897 	if (ret)
1898 		goto out_unregister;
1899 
1900 	return 0;
1901 
1902 out_unregister:
1903 	hwmon_device_unregister(data->hwmon_dev);
1904 out_kfree:
1905 	kfree(data->group.attrs);
1906 	return ret;
1907 }
1908 EXPORT_SYMBOL_GPL(pmbus_do_probe);
1909 
1910 int pmbus_do_remove(struct i2c_client *client)
1911 {
1912 	struct pmbus_data *data = i2c_get_clientdata(client);
1913 	hwmon_device_unregister(data->hwmon_dev);
1914 	kfree(data->group.attrs);
1915 	return 0;
1916 }
1917 EXPORT_SYMBOL_GPL(pmbus_do_remove);
1918 
1919 MODULE_AUTHOR("Guenter Roeck");
1920 MODULE_DESCRIPTION("PMBus core driver");
1921 MODULE_LICENSE("GPL");
1922