xref: /openbmc/linux/drivers/hwmon/pmbus/pmbus_core.c (revision f6723b56)
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 "pmbus.h"
33 
34 /*
35  * Number of additional attribute pointers to allocate
36  * with each call to krealloc
37  */
38 #define PMBUS_ATTR_ALLOC_SIZE	32
39 
40 /*
41  * Index into status register array, per status register group
42  */
43 #define PB_STATUS_BASE		0
44 #define PB_STATUS_VOUT_BASE	(PB_STATUS_BASE + PMBUS_PAGES)
45 #define PB_STATUS_IOUT_BASE	(PB_STATUS_VOUT_BASE + PMBUS_PAGES)
46 #define PB_STATUS_FAN_BASE	(PB_STATUS_IOUT_BASE + PMBUS_PAGES)
47 #define PB_STATUS_FAN34_BASE	(PB_STATUS_FAN_BASE + PMBUS_PAGES)
48 #define PB_STATUS_TEMP_BASE	(PB_STATUS_FAN34_BASE + PMBUS_PAGES)
49 #define PB_STATUS_INPUT_BASE	(PB_STATUS_TEMP_BASE + PMBUS_PAGES)
50 #define PB_STATUS_VMON_BASE	(PB_STATUS_INPUT_BASE + 1)
51 
52 #define PB_NUM_STATUS_REG	(PB_STATUS_VMON_BASE + 1)
53 
54 #define PMBUS_NAME_SIZE		24
55 
56 struct pmbus_sensor {
57 	struct pmbus_sensor *next;
58 	char name[PMBUS_NAME_SIZE];	/* sysfs sensor name */
59 	struct device_attribute attribute;
60 	u8 page;		/* page number */
61 	u16 reg;		/* register */
62 	enum pmbus_sensor_classes class;	/* sensor class */
63 	bool update;		/* runtime sensor update needed */
64 	int data;		/* Sensor data.
65 				   Negative if there was a read error */
66 };
67 #define to_pmbus_sensor(_attr) \
68 	container_of(_attr, struct pmbus_sensor, attribute)
69 
70 struct pmbus_boolean {
71 	char name[PMBUS_NAME_SIZE];	/* sysfs boolean name */
72 	struct sensor_device_attribute attribute;
73 	struct pmbus_sensor *s1;
74 	struct pmbus_sensor *s2;
75 };
76 #define to_pmbus_boolean(_attr) \
77 	container_of(_attr, struct pmbus_boolean, attribute)
78 
79 struct pmbus_label {
80 	char name[PMBUS_NAME_SIZE];	/* sysfs label name */
81 	struct device_attribute attribute;
82 	char label[PMBUS_NAME_SIZE];	/* label */
83 };
84 #define to_pmbus_label(_attr) \
85 	container_of(_attr, struct pmbus_label, attribute)
86 
87 struct pmbus_data {
88 	struct device *dev;
89 	struct device *hwmon_dev;
90 
91 	u32 flags;		/* from platform data */
92 
93 	int exponent[PMBUS_PAGES];
94 				/* linear mode: exponent for output voltages */
95 
96 	const struct pmbus_driver_info *info;
97 
98 	int max_attributes;
99 	int num_attributes;
100 	struct attribute_group group;
101 	const struct attribute_group *groups[2];
102 
103 	struct pmbus_sensor *sensors;
104 
105 	struct mutex update_lock;
106 	bool valid;
107 	unsigned long last_updated;	/* in jiffies */
108 
109 	/*
110 	 * A single status register covers multiple attributes,
111 	 * so we keep them all together.
112 	 */
113 	u8 status[PB_NUM_STATUS_REG];
114 	u8 status_register;
115 
116 	u8 currpage;
117 };
118 
119 void pmbus_clear_cache(struct i2c_client *client)
120 {
121 	struct pmbus_data *data = i2c_get_clientdata(client);
122 
123 	data->valid = false;
124 }
125 EXPORT_SYMBOL_GPL(pmbus_clear_cache);
126 
127 int pmbus_set_page(struct i2c_client *client, u8 page)
128 {
129 	struct pmbus_data *data = i2c_get_clientdata(client);
130 	int rv = 0;
131 	int newpage;
132 
133 	if (page != data->currpage) {
134 		rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
135 		newpage = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
136 		if (newpage != page)
137 			rv = -EIO;
138 		else
139 			data->currpage = page;
140 	}
141 	return rv;
142 }
143 EXPORT_SYMBOL_GPL(pmbus_set_page);
144 
145 int pmbus_write_byte(struct i2c_client *client, int page, u8 value)
146 {
147 	int rv;
148 
149 	if (page >= 0) {
150 		rv = pmbus_set_page(client, page);
151 		if (rv < 0)
152 			return rv;
153 	}
154 
155 	return i2c_smbus_write_byte(client, value);
156 }
157 EXPORT_SYMBOL_GPL(pmbus_write_byte);
158 
159 /*
160  * _pmbus_write_byte() is similar to pmbus_write_byte(), but checks if
161  * a device specific mapping function exists and calls it if necessary.
162  */
163 static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value)
164 {
165 	struct pmbus_data *data = i2c_get_clientdata(client);
166 	const struct pmbus_driver_info *info = data->info;
167 	int status;
168 
169 	if (info->write_byte) {
170 		status = info->write_byte(client, page, value);
171 		if (status != -ENODATA)
172 			return status;
173 	}
174 	return pmbus_write_byte(client, page, value);
175 }
176 
177 int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word)
178 {
179 	int rv;
180 
181 	rv = pmbus_set_page(client, page);
182 	if (rv < 0)
183 		return rv;
184 
185 	return i2c_smbus_write_word_data(client, reg, word);
186 }
187 EXPORT_SYMBOL_GPL(pmbus_write_word_data);
188 
189 /*
190  * _pmbus_write_word_data() is similar to pmbus_write_word_data(), but checks if
191  * a device specific mapping function exists and calls it if necessary.
192  */
193 static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg,
194 				  u16 word)
195 {
196 	struct pmbus_data *data = i2c_get_clientdata(client);
197 	const struct pmbus_driver_info *info = data->info;
198 	int status;
199 
200 	if (info->write_word_data) {
201 		status = info->write_word_data(client, page, reg, word);
202 		if (status != -ENODATA)
203 			return status;
204 	}
205 	if (reg >= PMBUS_VIRT_BASE)
206 		return -ENXIO;
207 	return pmbus_write_word_data(client, page, reg, word);
208 }
209 
210 int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg)
211 {
212 	int rv;
213 
214 	rv = pmbus_set_page(client, page);
215 	if (rv < 0)
216 		return rv;
217 
218 	return i2c_smbus_read_word_data(client, reg);
219 }
220 EXPORT_SYMBOL_GPL(pmbus_read_word_data);
221 
222 /*
223  * _pmbus_read_word_data() is similar to pmbus_read_word_data(), but checks if
224  * a device specific mapping function exists and calls it if necessary.
225  */
226 static int _pmbus_read_word_data(struct i2c_client *client, int page, int reg)
227 {
228 	struct pmbus_data *data = i2c_get_clientdata(client);
229 	const struct pmbus_driver_info *info = data->info;
230 	int status;
231 
232 	if (info->read_word_data) {
233 		status = info->read_word_data(client, page, reg);
234 		if (status != -ENODATA)
235 			return status;
236 	}
237 	if (reg >= PMBUS_VIRT_BASE)
238 		return -ENXIO;
239 	return pmbus_read_word_data(client, page, reg);
240 }
241 
242 int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg)
243 {
244 	int rv;
245 
246 	if (page >= 0) {
247 		rv = pmbus_set_page(client, page);
248 		if (rv < 0)
249 			return rv;
250 	}
251 
252 	return i2c_smbus_read_byte_data(client, reg);
253 }
254 EXPORT_SYMBOL_GPL(pmbus_read_byte_data);
255 
256 /*
257  * _pmbus_read_byte_data() is similar to pmbus_read_byte_data(), but checks if
258  * a device specific mapping function exists and calls it if necessary.
259  */
260 static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
261 {
262 	struct pmbus_data *data = i2c_get_clientdata(client);
263 	const struct pmbus_driver_info *info = data->info;
264 	int status;
265 
266 	if (info->read_byte_data) {
267 		status = info->read_byte_data(client, page, reg);
268 		if (status != -ENODATA)
269 			return status;
270 	}
271 	return pmbus_read_byte_data(client, page, reg);
272 }
273 
274 static void pmbus_clear_fault_page(struct i2c_client *client, int page)
275 {
276 	_pmbus_write_byte(client, page, PMBUS_CLEAR_FAULTS);
277 }
278 
279 void pmbus_clear_faults(struct i2c_client *client)
280 {
281 	struct pmbus_data *data = i2c_get_clientdata(client);
282 	int i;
283 
284 	for (i = 0; i < data->info->pages; i++)
285 		pmbus_clear_fault_page(client, i);
286 }
287 EXPORT_SYMBOL_GPL(pmbus_clear_faults);
288 
289 static int pmbus_check_status_cml(struct i2c_client *client)
290 {
291 	struct pmbus_data *data = i2c_get_clientdata(client);
292 	int status, status2;
293 
294 	status = _pmbus_read_byte_data(client, -1, data->status_register);
295 	if (status < 0 || (status & PB_STATUS_CML)) {
296 		status2 = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML);
297 		if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND))
298 			return -EIO;
299 	}
300 	return 0;
301 }
302 
303 static bool pmbus_check_register(struct i2c_client *client,
304 				 int (*func)(struct i2c_client *client,
305 					     int page, int reg),
306 				 int page, int reg)
307 {
308 	int rv;
309 	struct pmbus_data *data = i2c_get_clientdata(client);
310 
311 	rv = func(client, page, reg);
312 	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
313 		rv = pmbus_check_status_cml(client);
314 	pmbus_clear_fault_page(client, -1);
315 	return rv >= 0;
316 }
317 
318 bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg)
319 {
320 	return pmbus_check_register(client, _pmbus_read_byte_data, page, reg);
321 }
322 EXPORT_SYMBOL_GPL(pmbus_check_byte_register);
323 
324 bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
325 {
326 	return pmbus_check_register(client, _pmbus_read_word_data, page, reg);
327 }
328 EXPORT_SYMBOL_GPL(pmbus_check_word_register);
329 
330 const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
331 {
332 	struct pmbus_data *data = i2c_get_clientdata(client);
333 
334 	return data->info;
335 }
336 EXPORT_SYMBOL_GPL(pmbus_get_driver_info);
337 
338 static struct _pmbus_status {
339 	u32 func;
340 	u16 base;
341 	u16 reg;
342 } pmbus_status[] = {
343 	{ PMBUS_HAVE_STATUS_VOUT, PB_STATUS_VOUT_BASE, PMBUS_STATUS_VOUT },
344 	{ PMBUS_HAVE_STATUS_IOUT, PB_STATUS_IOUT_BASE, PMBUS_STATUS_IOUT },
345 	{ PMBUS_HAVE_STATUS_TEMP, PB_STATUS_TEMP_BASE,
346 	  PMBUS_STATUS_TEMPERATURE },
347 	{ PMBUS_HAVE_STATUS_FAN12, PB_STATUS_FAN_BASE, PMBUS_STATUS_FAN_12 },
348 	{ PMBUS_HAVE_STATUS_FAN34, PB_STATUS_FAN34_BASE, PMBUS_STATUS_FAN_34 },
349 };
350 
351 static struct pmbus_data *pmbus_update_device(struct device *dev)
352 {
353 	struct i2c_client *client = to_i2c_client(dev->parent);
354 	struct pmbus_data *data = i2c_get_clientdata(client);
355 	const struct pmbus_driver_info *info = data->info;
356 	struct pmbus_sensor *sensor;
357 
358 	mutex_lock(&data->update_lock);
359 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
360 		int i, j;
361 
362 		for (i = 0; i < info->pages; i++) {
363 			data->status[PB_STATUS_BASE + i]
364 			    = _pmbus_read_byte_data(client, i,
365 						    data->status_register);
366 			for (j = 0; j < ARRAY_SIZE(pmbus_status); j++) {
367 				struct _pmbus_status *s = &pmbus_status[j];
368 
369 				if (!(info->func[i] & s->func))
370 					continue;
371 				data->status[s->base + i]
372 					= _pmbus_read_byte_data(client, i,
373 								s->reg);
374 			}
375 		}
376 
377 		if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
378 			data->status[PB_STATUS_INPUT_BASE]
379 			  = _pmbus_read_byte_data(client, 0,
380 						  PMBUS_STATUS_INPUT);
381 
382 		if (info->func[0] & PMBUS_HAVE_STATUS_VMON)
383 			data->status[PB_STATUS_VMON_BASE]
384 			  = _pmbus_read_byte_data(client, 0,
385 						  PMBUS_VIRT_STATUS_VMON);
386 
387 		for (sensor = data->sensors; sensor; sensor = sensor->next) {
388 			if (!data->valid || sensor->update)
389 				sensor->data
390 				    = _pmbus_read_word_data(client,
391 							    sensor->page,
392 							    sensor->reg);
393 		}
394 		pmbus_clear_faults(client);
395 		data->last_updated = jiffies;
396 		data->valid = 1;
397 	}
398 	mutex_unlock(&data->update_lock);
399 	return data;
400 }
401 
402 /*
403  * Convert linear sensor values to milli- or micro-units
404  * depending on sensor type.
405  */
406 static long pmbus_reg2data_linear(struct pmbus_data *data,
407 				  struct pmbus_sensor *sensor)
408 {
409 	s16 exponent;
410 	s32 mantissa;
411 	long val;
412 
413 	if (sensor->class == PSC_VOLTAGE_OUT) {	/* LINEAR16 */
414 		exponent = data->exponent[sensor->page];
415 		mantissa = (u16) sensor->data;
416 	} else {				/* LINEAR11 */
417 		exponent = ((s16)sensor->data) >> 11;
418 		mantissa = ((s16)((sensor->data & 0x7ff) << 5)) >> 5;
419 	}
420 
421 	val = mantissa;
422 
423 	/* scale result to milli-units for all sensors except fans */
424 	if (sensor->class != PSC_FAN)
425 		val = val * 1000L;
426 
427 	/* scale result to micro-units for power sensors */
428 	if (sensor->class == PSC_POWER)
429 		val = val * 1000L;
430 
431 	if (exponent >= 0)
432 		val <<= exponent;
433 	else
434 		val >>= -exponent;
435 
436 	return val;
437 }
438 
439 /*
440  * Convert direct sensor values to milli- or micro-units
441  * depending on sensor type.
442  */
443 static long pmbus_reg2data_direct(struct pmbus_data *data,
444 				  struct pmbus_sensor *sensor)
445 {
446 	long val = (s16) sensor->data;
447 	long m, b, R;
448 
449 	m = data->info->m[sensor->class];
450 	b = data->info->b[sensor->class];
451 	R = data->info->R[sensor->class];
452 
453 	if (m == 0)
454 		return 0;
455 
456 	/* X = 1/m * (Y * 10^-R - b) */
457 	R = -R;
458 	/* scale result to milli-units for everything but fans */
459 	if (sensor->class != PSC_FAN) {
460 		R += 3;
461 		b *= 1000;
462 	}
463 
464 	/* scale result to micro-units for power sensors */
465 	if (sensor->class == PSC_POWER) {
466 		R += 3;
467 		b *= 1000;
468 	}
469 
470 	while (R > 0) {
471 		val *= 10;
472 		R--;
473 	}
474 	while (R < 0) {
475 		val = DIV_ROUND_CLOSEST(val, 10);
476 		R++;
477 	}
478 
479 	return (val - b) / m;
480 }
481 
482 /*
483  * Convert VID sensor values to milli- or micro-units
484  * depending on sensor type.
485  * We currently only support VR11.
486  */
487 static long pmbus_reg2data_vid(struct pmbus_data *data,
488 			       struct pmbus_sensor *sensor)
489 {
490 	long val = sensor->data;
491 
492 	if (val < 0x02 || val > 0xb2)
493 		return 0;
494 	return DIV_ROUND_CLOSEST(160000 - (val - 2) * 625, 100);
495 }
496 
497 static long pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
498 {
499 	long val;
500 
501 	switch (data->info->format[sensor->class]) {
502 	case direct:
503 		val = pmbus_reg2data_direct(data, sensor);
504 		break;
505 	case vid:
506 		val = pmbus_reg2data_vid(data, sensor);
507 		break;
508 	case linear:
509 	default:
510 		val = pmbus_reg2data_linear(data, sensor);
511 		break;
512 	}
513 	return val;
514 }
515 
516 #define MAX_MANTISSA	(1023 * 1000)
517 #define MIN_MANTISSA	(511 * 1000)
518 
519 static u16 pmbus_data2reg_linear(struct pmbus_data *data,
520 				 struct pmbus_sensor *sensor, long val)
521 {
522 	s16 exponent = 0, mantissa;
523 	bool negative = false;
524 
525 	/* simple case */
526 	if (val == 0)
527 		return 0;
528 
529 	if (sensor->class == PSC_VOLTAGE_OUT) {
530 		/* LINEAR16 does not support negative voltages */
531 		if (val < 0)
532 			return 0;
533 
534 		/*
535 		 * For a static exponents, we don't have a choice
536 		 * but to adjust the value to it.
537 		 */
538 		if (data->exponent[sensor->page] < 0)
539 			val <<= -data->exponent[sensor->page];
540 		else
541 			val >>= data->exponent[sensor->page];
542 		val = DIV_ROUND_CLOSEST(val, 1000);
543 		return val & 0xffff;
544 	}
545 
546 	if (val < 0) {
547 		negative = true;
548 		val = -val;
549 	}
550 
551 	/* Power is in uW. Convert to mW before converting. */
552 	if (sensor->class == PSC_POWER)
553 		val = DIV_ROUND_CLOSEST(val, 1000L);
554 
555 	/*
556 	 * For simplicity, convert fan data to milli-units
557 	 * before calculating the exponent.
558 	 */
559 	if (sensor->class == PSC_FAN)
560 		val = val * 1000;
561 
562 	/* Reduce large mantissa until it fits into 10 bit */
563 	while (val >= MAX_MANTISSA && exponent < 15) {
564 		exponent++;
565 		val >>= 1;
566 	}
567 	/* Increase small mantissa to improve precision */
568 	while (val < MIN_MANTISSA && exponent > -15) {
569 		exponent--;
570 		val <<= 1;
571 	}
572 
573 	/* Convert mantissa from milli-units to units */
574 	mantissa = DIV_ROUND_CLOSEST(val, 1000);
575 
576 	/* Ensure that resulting number is within range */
577 	if (mantissa > 0x3ff)
578 		mantissa = 0x3ff;
579 
580 	/* restore sign */
581 	if (negative)
582 		mantissa = -mantissa;
583 
584 	/* Convert to 5 bit exponent, 11 bit mantissa */
585 	return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
586 }
587 
588 static u16 pmbus_data2reg_direct(struct pmbus_data *data,
589 				 struct pmbus_sensor *sensor, long val)
590 {
591 	long m, b, R;
592 
593 	m = data->info->m[sensor->class];
594 	b = data->info->b[sensor->class];
595 	R = data->info->R[sensor->class];
596 
597 	/* Power is in uW. Adjust R and b. */
598 	if (sensor->class == PSC_POWER) {
599 		R -= 3;
600 		b *= 1000;
601 	}
602 
603 	/* Calculate Y = (m * X + b) * 10^R */
604 	if (sensor->class != PSC_FAN) {
605 		R -= 3;		/* Adjust R and b for data in milli-units */
606 		b *= 1000;
607 	}
608 	val = val * m + b;
609 
610 	while (R > 0) {
611 		val *= 10;
612 		R--;
613 	}
614 	while (R < 0) {
615 		val = DIV_ROUND_CLOSEST(val, 10);
616 		R++;
617 	}
618 
619 	return val;
620 }
621 
622 static u16 pmbus_data2reg_vid(struct pmbus_data *data,
623 			      struct pmbus_sensor *sensor, long val)
624 {
625 	val = clamp_val(val, 500, 1600);
626 
627 	return 2 + DIV_ROUND_CLOSEST((1600 - val) * 100, 625);
628 }
629 
630 static u16 pmbus_data2reg(struct pmbus_data *data,
631 			  struct pmbus_sensor *sensor, long val)
632 {
633 	u16 regval;
634 
635 	switch (data->info->format[sensor->class]) {
636 	case direct:
637 		regval = pmbus_data2reg_direct(data, sensor, val);
638 		break;
639 	case vid:
640 		regval = pmbus_data2reg_vid(data, sensor, val);
641 		break;
642 	case linear:
643 	default:
644 		regval = pmbus_data2reg_linear(data, sensor, val);
645 		break;
646 	}
647 	return regval;
648 }
649 
650 /*
651  * Return boolean calculated from converted data.
652  * <index> defines a status register index and mask.
653  * The mask is in the lower 8 bits, the register index is in bits 8..23.
654  *
655  * The associated pmbus_boolean structure contains optional pointers to two
656  * sensor attributes. If specified, those attributes are compared against each
657  * other to determine if a limit has been exceeded.
658  *
659  * If the sensor attribute pointers are NULL, the function returns true if
660  * (status[reg] & mask) is true.
661  *
662  * If sensor attribute pointers are provided, a comparison against a specified
663  * limit has to be performed to determine the boolean result.
664  * In this case, the function returns true if v1 >= v2 (where v1 and v2 are
665  * sensor values referenced by sensor attribute pointers s1 and s2).
666  *
667  * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>.
668  * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>.
669  *
670  * If a negative value is stored in any of the referenced registers, this value
671  * reflects an error code which will be returned.
672  */
673 static int pmbus_get_boolean(struct pmbus_data *data, struct pmbus_boolean *b,
674 			     int index)
675 {
676 	struct pmbus_sensor *s1 = b->s1;
677 	struct pmbus_sensor *s2 = b->s2;
678 	u16 reg = (index >> 8) & 0xffff;
679 	u8 mask = index & 0xff;
680 	int ret, status;
681 	u8 regval;
682 
683 	status = data->status[reg];
684 	if (status < 0)
685 		return status;
686 
687 	regval = status & mask;
688 	if (!s1 && !s2) {
689 		ret = !!regval;
690 	} else if (!s1 || !s2) {
691 		WARN(1, "Bad boolean descriptor %p: s1=%p, s2=%p\n", b, s1, s2);
692 		return 0;
693 	} else {
694 		long v1, v2;
695 
696 		if (s1->data < 0)
697 			return s1->data;
698 		if (s2->data < 0)
699 			return s2->data;
700 
701 		v1 = pmbus_reg2data(data, s1);
702 		v2 = pmbus_reg2data(data, s2);
703 		ret = !!(regval && v1 >= v2);
704 	}
705 	return ret;
706 }
707 
708 static ssize_t pmbus_show_boolean(struct device *dev,
709 				  struct device_attribute *da, char *buf)
710 {
711 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
712 	struct pmbus_boolean *boolean = to_pmbus_boolean(attr);
713 	struct pmbus_data *data = pmbus_update_device(dev);
714 	int val;
715 
716 	val = pmbus_get_boolean(data, boolean, attr->index);
717 	if (val < 0)
718 		return val;
719 	return snprintf(buf, PAGE_SIZE, "%d\n", val);
720 }
721 
722 static ssize_t pmbus_show_sensor(struct device *dev,
723 				 struct device_attribute *devattr, char *buf)
724 {
725 	struct pmbus_data *data = pmbus_update_device(dev);
726 	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
727 
728 	if (sensor->data < 0)
729 		return sensor->data;
730 
731 	return snprintf(buf, PAGE_SIZE, "%ld\n", pmbus_reg2data(data, sensor));
732 }
733 
734 static ssize_t pmbus_set_sensor(struct device *dev,
735 				struct device_attribute *devattr,
736 				const char *buf, size_t count)
737 {
738 	struct i2c_client *client = to_i2c_client(dev->parent);
739 	struct pmbus_data *data = i2c_get_clientdata(client);
740 	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
741 	ssize_t rv = count;
742 	long val = 0;
743 	int ret;
744 	u16 regval;
745 
746 	if (kstrtol(buf, 10, &val) < 0)
747 		return -EINVAL;
748 
749 	mutex_lock(&data->update_lock);
750 	regval = pmbus_data2reg(data, sensor, val);
751 	ret = _pmbus_write_word_data(client, sensor->page, sensor->reg, regval);
752 	if (ret < 0)
753 		rv = ret;
754 	else
755 		sensor->data = regval;
756 	mutex_unlock(&data->update_lock);
757 	return rv;
758 }
759 
760 static ssize_t pmbus_show_label(struct device *dev,
761 				struct device_attribute *da, char *buf)
762 {
763 	struct pmbus_label *label = to_pmbus_label(da);
764 
765 	return snprintf(buf, PAGE_SIZE, "%s\n", label->label);
766 }
767 
768 static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
769 {
770 	if (data->num_attributes >= data->max_attributes - 1) {
771 		int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE;
772 		void *new_attrs = krealloc(data->group.attrs,
773 					   new_max_attrs * sizeof(void *),
774 					   GFP_KERNEL);
775 		if (!new_attrs)
776 			return -ENOMEM;
777 		data->group.attrs = new_attrs;
778 		data->max_attributes = new_max_attrs;
779 	}
780 
781 	data->group.attrs[data->num_attributes++] = attr;
782 	data->group.attrs[data->num_attributes] = NULL;
783 	return 0;
784 }
785 
786 static void pmbus_dev_attr_init(struct device_attribute *dev_attr,
787 				const char *name,
788 				umode_t mode,
789 				ssize_t (*show)(struct device *dev,
790 						struct device_attribute *attr,
791 						char *buf),
792 				ssize_t (*store)(struct device *dev,
793 						 struct device_attribute *attr,
794 						 const char *buf, size_t count))
795 {
796 	sysfs_attr_init(&dev_attr->attr);
797 	dev_attr->attr.name = name;
798 	dev_attr->attr.mode = mode;
799 	dev_attr->show = show;
800 	dev_attr->store = store;
801 }
802 
803 static void pmbus_attr_init(struct sensor_device_attribute *a,
804 			    const char *name,
805 			    umode_t mode,
806 			    ssize_t (*show)(struct device *dev,
807 					    struct device_attribute *attr,
808 					    char *buf),
809 			    ssize_t (*store)(struct device *dev,
810 					     struct device_attribute *attr,
811 					     const char *buf, size_t count),
812 			    int idx)
813 {
814 	pmbus_dev_attr_init(&a->dev_attr, name, mode, show, store);
815 	a->index = idx;
816 }
817 
818 static int pmbus_add_boolean(struct pmbus_data *data,
819 			     const char *name, const char *type, int seq,
820 			     struct pmbus_sensor *s1,
821 			     struct pmbus_sensor *s2,
822 			     u16 reg, u8 mask)
823 {
824 	struct pmbus_boolean *boolean;
825 	struct sensor_device_attribute *a;
826 
827 	boolean = devm_kzalloc(data->dev, sizeof(*boolean), GFP_KERNEL);
828 	if (!boolean)
829 		return -ENOMEM;
830 
831 	a = &boolean->attribute;
832 
833 	snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
834 		 name, seq, type);
835 	boolean->s1 = s1;
836 	boolean->s2 = s2;
837 	pmbus_attr_init(a, boolean->name, S_IRUGO, pmbus_show_boolean, NULL,
838 			(reg << 8) | mask);
839 
840 	return pmbus_add_attribute(data, &a->dev_attr.attr);
841 }
842 
843 static struct pmbus_sensor *pmbus_add_sensor(struct pmbus_data *data,
844 					     const char *name, const char *type,
845 					     int seq, int page, int reg,
846 					     enum pmbus_sensor_classes class,
847 					     bool update, bool readonly)
848 {
849 	struct pmbus_sensor *sensor;
850 	struct device_attribute *a;
851 
852 	sensor = devm_kzalloc(data->dev, sizeof(*sensor), GFP_KERNEL);
853 	if (!sensor)
854 		return NULL;
855 	a = &sensor->attribute;
856 
857 	snprintf(sensor->name, sizeof(sensor->name), "%s%d_%s",
858 		 name, seq, type);
859 	sensor->page = page;
860 	sensor->reg = reg;
861 	sensor->class = class;
862 	sensor->update = update;
863 	pmbus_dev_attr_init(a, sensor->name,
864 			    readonly ? S_IRUGO : S_IRUGO | S_IWUSR,
865 			    pmbus_show_sensor, pmbus_set_sensor);
866 
867 	if (pmbus_add_attribute(data, &a->attr))
868 		return NULL;
869 
870 	sensor->next = data->sensors;
871 	data->sensors = sensor;
872 
873 	return sensor;
874 }
875 
876 static int pmbus_add_label(struct pmbus_data *data,
877 			   const char *name, int seq,
878 			   const char *lstring, int index)
879 {
880 	struct pmbus_label *label;
881 	struct device_attribute *a;
882 
883 	label = devm_kzalloc(data->dev, sizeof(*label), GFP_KERNEL);
884 	if (!label)
885 		return -ENOMEM;
886 
887 	a = &label->attribute;
888 
889 	snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
890 	if (!index)
891 		strncpy(label->label, lstring, sizeof(label->label) - 1);
892 	else
893 		snprintf(label->label, sizeof(label->label), "%s%d", lstring,
894 			 index);
895 
896 	pmbus_dev_attr_init(a, label->name, S_IRUGO, pmbus_show_label, NULL);
897 	return pmbus_add_attribute(data, &a->attr);
898 }
899 
900 /*
901  * Search for attributes. Allocate sensors, booleans, and labels as needed.
902  */
903 
904 /*
905  * The pmbus_limit_attr structure describes a single limit attribute
906  * and its associated alarm attribute.
907  */
908 struct pmbus_limit_attr {
909 	u16 reg;		/* Limit register */
910 	u16 sbit;		/* Alarm attribute status bit */
911 	bool update;		/* True if register needs updates */
912 	bool low;		/* True if low limit; for limits with compare
913 				   functions only */
914 	const char *attr;	/* Attribute name */
915 	const char *alarm;	/* Alarm attribute name */
916 };
917 
918 /*
919  * The pmbus_sensor_attr structure describes one sensor attribute. This
920  * description includes a reference to the associated limit attributes.
921  */
922 struct pmbus_sensor_attr {
923 	u16 reg;			/* sensor register */
924 	u8 gbit;			/* generic status bit */
925 	u8 nlimit;			/* # of limit registers */
926 	enum pmbus_sensor_classes class;/* sensor class */
927 	const char *label;		/* sensor label */
928 	bool paged;			/* true if paged sensor */
929 	bool update;			/* true if update needed */
930 	bool compare;			/* true if compare function needed */
931 	u32 func;			/* sensor mask */
932 	u32 sfunc;			/* sensor status mask */
933 	int sbase;			/* status base register */
934 	const struct pmbus_limit_attr *limit;/* limit registers */
935 };
936 
937 /*
938  * Add a set of limit attributes and, if supported, the associated
939  * alarm attributes.
940  * returns 0 if no alarm register found, 1 if an alarm register was found,
941  * < 0 on errors.
942  */
943 static int pmbus_add_limit_attrs(struct i2c_client *client,
944 				 struct pmbus_data *data,
945 				 const struct pmbus_driver_info *info,
946 				 const char *name, int index, int page,
947 				 struct pmbus_sensor *base,
948 				 const struct pmbus_sensor_attr *attr)
949 {
950 	const struct pmbus_limit_attr *l = attr->limit;
951 	int nlimit = attr->nlimit;
952 	int have_alarm = 0;
953 	int i, ret;
954 	struct pmbus_sensor *curr;
955 
956 	for (i = 0; i < nlimit; i++) {
957 		if (pmbus_check_word_register(client, page, l->reg)) {
958 			curr = pmbus_add_sensor(data, name, l->attr, index,
959 						page, l->reg, attr->class,
960 						attr->update || l->update,
961 						false);
962 			if (!curr)
963 				return -ENOMEM;
964 			if (l->sbit && (info->func[page] & attr->sfunc)) {
965 				ret = pmbus_add_boolean(data, name,
966 					l->alarm, index,
967 					attr->compare ?  l->low ? curr : base
968 						      : NULL,
969 					attr->compare ? l->low ? base : curr
970 						      : NULL,
971 					attr->sbase + page, l->sbit);
972 				if (ret)
973 					return ret;
974 				have_alarm = 1;
975 			}
976 		}
977 		l++;
978 	}
979 	return have_alarm;
980 }
981 
982 static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
983 				      struct pmbus_data *data,
984 				      const struct pmbus_driver_info *info,
985 				      const char *name,
986 				      int index, int page,
987 				      const struct pmbus_sensor_attr *attr)
988 {
989 	struct pmbus_sensor *base;
990 	int ret;
991 
992 	if (attr->label) {
993 		ret = pmbus_add_label(data, name, index, attr->label,
994 				      attr->paged ? page + 1 : 0);
995 		if (ret)
996 			return ret;
997 	}
998 	base = pmbus_add_sensor(data, name, "input", index, page, attr->reg,
999 				attr->class, true, true);
1000 	if (!base)
1001 		return -ENOMEM;
1002 	if (attr->sfunc) {
1003 		ret = pmbus_add_limit_attrs(client, data, info, name,
1004 					    index, page, base, attr);
1005 		if (ret < 0)
1006 			return ret;
1007 		/*
1008 		 * Add generic alarm attribute only if there are no individual
1009 		 * alarm attributes, if there is a global alarm bit, and if
1010 		 * the generic status register for this page is accessible.
1011 		 */
1012 		if (!ret && attr->gbit &&
1013 		    pmbus_check_byte_register(client, page,
1014 					      data->status_register)) {
1015 			ret = pmbus_add_boolean(data, name, "alarm", index,
1016 						NULL, NULL,
1017 						PB_STATUS_BASE + page,
1018 						attr->gbit);
1019 			if (ret)
1020 				return ret;
1021 		}
1022 	}
1023 	return 0;
1024 }
1025 
1026 static int pmbus_add_sensor_attrs(struct i2c_client *client,
1027 				  struct pmbus_data *data,
1028 				  const char *name,
1029 				  const struct pmbus_sensor_attr *attrs,
1030 				  int nattrs)
1031 {
1032 	const struct pmbus_driver_info *info = data->info;
1033 	int index, i;
1034 	int ret;
1035 
1036 	index = 1;
1037 	for (i = 0; i < nattrs; i++) {
1038 		int page, pages;
1039 
1040 		pages = attrs->paged ? info->pages : 1;
1041 		for (page = 0; page < pages; page++) {
1042 			if (!(info->func[page] & attrs->func))
1043 				continue;
1044 			ret = pmbus_add_sensor_attrs_one(client, data, info,
1045 							 name, index, page,
1046 							 attrs);
1047 			if (ret)
1048 				return ret;
1049 			index++;
1050 		}
1051 		attrs++;
1052 	}
1053 	return 0;
1054 }
1055 
1056 static const struct pmbus_limit_attr vin_limit_attrs[] = {
1057 	{
1058 		.reg = PMBUS_VIN_UV_WARN_LIMIT,
1059 		.attr = "min",
1060 		.alarm = "min_alarm",
1061 		.sbit = PB_VOLTAGE_UV_WARNING,
1062 	}, {
1063 		.reg = PMBUS_VIN_UV_FAULT_LIMIT,
1064 		.attr = "lcrit",
1065 		.alarm = "lcrit_alarm",
1066 		.sbit = PB_VOLTAGE_UV_FAULT,
1067 	}, {
1068 		.reg = PMBUS_VIN_OV_WARN_LIMIT,
1069 		.attr = "max",
1070 		.alarm = "max_alarm",
1071 		.sbit = PB_VOLTAGE_OV_WARNING,
1072 	}, {
1073 		.reg = PMBUS_VIN_OV_FAULT_LIMIT,
1074 		.attr = "crit",
1075 		.alarm = "crit_alarm",
1076 		.sbit = PB_VOLTAGE_OV_FAULT,
1077 	}, {
1078 		.reg = PMBUS_VIRT_READ_VIN_AVG,
1079 		.update = true,
1080 		.attr = "average",
1081 	}, {
1082 		.reg = PMBUS_VIRT_READ_VIN_MIN,
1083 		.update = true,
1084 		.attr = "lowest",
1085 	}, {
1086 		.reg = PMBUS_VIRT_READ_VIN_MAX,
1087 		.update = true,
1088 		.attr = "highest",
1089 	}, {
1090 		.reg = PMBUS_VIRT_RESET_VIN_HISTORY,
1091 		.attr = "reset_history",
1092 	},
1093 };
1094 
1095 static const struct pmbus_limit_attr vmon_limit_attrs[] = {
1096 	{
1097 		.reg = PMBUS_VIRT_VMON_UV_WARN_LIMIT,
1098 		.attr = "min",
1099 		.alarm = "min_alarm",
1100 		.sbit = PB_VOLTAGE_UV_WARNING,
1101 	}, {
1102 		.reg = PMBUS_VIRT_VMON_UV_FAULT_LIMIT,
1103 		.attr = "lcrit",
1104 		.alarm = "lcrit_alarm",
1105 		.sbit = PB_VOLTAGE_UV_FAULT,
1106 	}, {
1107 		.reg = PMBUS_VIRT_VMON_OV_WARN_LIMIT,
1108 		.attr = "max",
1109 		.alarm = "max_alarm",
1110 		.sbit = PB_VOLTAGE_OV_WARNING,
1111 	}, {
1112 		.reg = PMBUS_VIRT_VMON_OV_FAULT_LIMIT,
1113 		.attr = "crit",
1114 		.alarm = "crit_alarm",
1115 		.sbit = PB_VOLTAGE_OV_FAULT,
1116 	}
1117 };
1118 
1119 static const struct pmbus_limit_attr vout_limit_attrs[] = {
1120 	{
1121 		.reg = PMBUS_VOUT_UV_WARN_LIMIT,
1122 		.attr = "min",
1123 		.alarm = "min_alarm",
1124 		.sbit = PB_VOLTAGE_UV_WARNING,
1125 	}, {
1126 		.reg = PMBUS_VOUT_UV_FAULT_LIMIT,
1127 		.attr = "lcrit",
1128 		.alarm = "lcrit_alarm",
1129 		.sbit = PB_VOLTAGE_UV_FAULT,
1130 	}, {
1131 		.reg = PMBUS_VOUT_OV_WARN_LIMIT,
1132 		.attr = "max",
1133 		.alarm = "max_alarm",
1134 		.sbit = PB_VOLTAGE_OV_WARNING,
1135 	}, {
1136 		.reg = PMBUS_VOUT_OV_FAULT_LIMIT,
1137 		.attr = "crit",
1138 		.alarm = "crit_alarm",
1139 		.sbit = PB_VOLTAGE_OV_FAULT,
1140 	}, {
1141 		.reg = PMBUS_VIRT_READ_VOUT_AVG,
1142 		.update = true,
1143 		.attr = "average",
1144 	}, {
1145 		.reg = PMBUS_VIRT_READ_VOUT_MIN,
1146 		.update = true,
1147 		.attr = "lowest",
1148 	}, {
1149 		.reg = PMBUS_VIRT_READ_VOUT_MAX,
1150 		.update = true,
1151 		.attr = "highest",
1152 	}, {
1153 		.reg = PMBUS_VIRT_RESET_VOUT_HISTORY,
1154 		.attr = "reset_history",
1155 	}
1156 };
1157 
1158 static const struct pmbus_sensor_attr voltage_attributes[] = {
1159 	{
1160 		.reg = PMBUS_READ_VIN,
1161 		.class = PSC_VOLTAGE_IN,
1162 		.label = "vin",
1163 		.func = PMBUS_HAVE_VIN,
1164 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1165 		.sbase = PB_STATUS_INPUT_BASE,
1166 		.gbit = PB_STATUS_VIN_UV,
1167 		.limit = vin_limit_attrs,
1168 		.nlimit = ARRAY_SIZE(vin_limit_attrs),
1169 	}, {
1170 		.reg = PMBUS_VIRT_READ_VMON,
1171 		.class = PSC_VOLTAGE_IN,
1172 		.label = "vmon",
1173 		.func = PMBUS_HAVE_VMON,
1174 		.sfunc = PMBUS_HAVE_STATUS_VMON,
1175 		.sbase = PB_STATUS_VMON_BASE,
1176 		.limit = vmon_limit_attrs,
1177 		.nlimit = ARRAY_SIZE(vmon_limit_attrs),
1178 	}, {
1179 		.reg = PMBUS_READ_VCAP,
1180 		.class = PSC_VOLTAGE_IN,
1181 		.label = "vcap",
1182 		.func = PMBUS_HAVE_VCAP,
1183 	}, {
1184 		.reg = PMBUS_READ_VOUT,
1185 		.class = PSC_VOLTAGE_OUT,
1186 		.label = "vout",
1187 		.paged = true,
1188 		.func = PMBUS_HAVE_VOUT,
1189 		.sfunc = PMBUS_HAVE_STATUS_VOUT,
1190 		.sbase = PB_STATUS_VOUT_BASE,
1191 		.gbit = PB_STATUS_VOUT_OV,
1192 		.limit = vout_limit_attrs,
1193 		.nlimit = ARRAY_SIZE(vout_limit_attrs),
1194 	}
1195 };
1196 
1197 /* Current attributes */
1198 
1199 static const struct pmbus_limit_attr iin_limit_attrs[] = {
1200 	{
1201 		.reg = PMBUS_IIN_OC_WARN_LIMIT,
1202 		.attr = "max",
1203 		.alarm = "max_alarm",
1204 		.sbit = PB_IIN_OC_WARNING,
1205 	}, {
1206 		.reg = PMBUS_IIN_OC_FAULT_LIMIT,
1207 		.attr = "crit",
1208 		.alarm = "crit_alarm",
1209 		.sbit = PB_IIN_OC_FAULT,
1210 	}, {
1211 		.reg = PMBUS_VIRT_READ_IIN_AVG,
1212 		.update = true,
1213 		.attr = "average",
1214 	}, {
1215 		.reg = PMBUS_VIRT_READ_IIN_MIN,
1216 		.update = true,
1217 		.attr = "lowest",
1218 	}, {
1219 		.reg = PMBUS_VIRT_READ_IIN_MAX,
1220 		.update = true,
1221 		.attr = "highest",
1222 	}, {
1223 		.reg = PMBUS_VIRT_RESET_IIN_HISTORY,
1224 		.attr = "reset_history",
1225 	}
1226 };
1227 
1228 static const struct pmbus_limit_attr iout_limit_attrs[] = {
1229 	{
1230 		.reg = PMBUS_IOUT_OC_WARN_LIMIT,
1231 		.attr = "max",
1232 		.alarm = "max_alarm",
1233 		.sbit = PB_IOUT_OC_WARNING,
1234 	}, {
1235 		.reg = PMBUS_IOUT_UC_FAULT_LIMIT,
1236 		.attr = "lcrit",
1237 		.alarm = "lcrit_alarm",
1238 		.sbit = PB_IOUT_UC_FAULT,
1239 	}, {
1240 		.reg = PMBUS_IOUT_OC_FAULT_LIMIT,
1241 		.attr = "crit",
1242 		.alarm = "crit_alarm",
1243 		.sbit = PB_IOUT_OC_FAULT,
1244 	}, {
1245 		.reg = PMBUS_VIRT_READ_IOUT_AVG,
1246 		.update = true,
1247 		.attr = "average",
1248 	}, {
1249 		.reg = PMBUS_VIRT_READ_IOUT_MIN,
1250 		.update = true,
1251 		.attr = "lowest",
1252 	}, {
1253 		.reg = PMBUS_VIRT_READ_IOUT_MAX,
1254 		.update = true,
1255 		.attr = "highest",
1256 	}, {
1257 		.reg = PMBUS_VIRT_RESET_IOUT_HISTORY,
1258 		.attr = "reset_history",
1259 	}
1260 };
1261 
1262 static const struct pmbus_sensor_attr current_attributes[] = {
1263 	{
1264 		.reg = PMBUS_READ_IIN,
1265 		.class = PSC_CURRENT_IN,
1266 		.label = "iin",
1267 		.func = PMBUS_HAVE_IIN,
1268 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1269 		.sbase = PB_STATUS_INPUT_BASE,
1270 		.limit = iin_limit_attrs,
1271 		.nlimit = ARRAY_SIZE(iin_limit_attrs),
1272 	}, {
1273 		.reg = PMBUS_READ_IOUT,
1274 		.class = PSC_CURRENT_OUT,
1275 		.label = "iout",
1276 		.paged = true,
1277 		.func = PMBUS_HAVE_IOUT,
1278 		.sfunc = PMBUS_HAVE_STATUS_IOUT,
1279 		.sbase = PB_STATUS_IOUT_BASE,
1280 		.gbit = PB_STATUS_IOUT_OC,
1281 		.limit = iout_limit_attrs,
1282 		.nlimit = ARRAY_SIZE(iout_limit_attrs),
1283 	}
1284 };
1285 
1286 /* Power attributes */
1287 
1288 static const struct pmbus_limit_attr pin_limit_attrs[] = {
1289 	{
1290 		.reg = PMBUS_PIN_OP_WARN_LIMIT,
1291 		.attr = "max",
1292 		.alarm = "alarm",
1293 		.sbit = PB_PIN_OP_WARNING,
1294 	}, {
1295 		.reg = PMBUS_VIRT_READ_PIN_AVG,
1296 		.update = true,
1297 		.attr = "average",
1298 	}, {
1299 		.reg = PMBUS_VIRT_READ_PIN_MAX,
1300 		.update = true,
1301 		.attr = "input_highest",
1302 	}, {
1303 		.reg = PMBUS_VIRT_RESET_PIN_HISTORY,
1304 		.attr = "reset_history",
1305 	}
1306 };
1307 
1308 static const struct pmbus_limit_attr pout_limit_attrs[] = {
1309 	{
1310 		.reg = PMBUS_POUT_MAX,
1311 		.attr = "cap",
1312 		.alarm = "cap_alarm",
1313 		.sbit = PB_POWER_LIMITING,
1314 	}, {
1315 		.reg = PMBUS_POUT_OP_WARN_LIMIT,
1316 		.attr = "max",
1317 		.alarm = "max_alarm",
1318 		.sbit = PB_POUT_OP_WARNING,
1319 	}, {
1320 		.reg = PMBUS_POUT_OP_FAULT_LIMIT,
1321 		.attr = "crit",
1322 		.alarm = "crit_alarm",
1323 		.sbit = PB_POUT_OP_FAULT,
1324 	}, {
1325 		.reg = PMBUS_VIRT_READ_POUT_AVG,
1326 		.update = true,
1327 		.attr = "average",
1328 	}, {
1329 		.reg = PMBUS_VIRT_READ_POUT_MAX,
1330 		.update = true,
1331 		.attr = "input_highest",
1332 	}, {
1333 		.reg = PMBUS_VIRT_RESET_POUT_HISTORY,
1334 		.attr = "reset_history",
1335 	}
1336 };
1337 
1338 static const struct pmbus_sensor_attr power_attributes[] = {
1339 	{
1340 		.reg = PMBUS_READ_PIN,
1341 		.class = PSC_POWER,
1342 		.label = "pin",
1343 		.func = PMBUS_HAVE_PIN,
1344 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1345 		.sbase = PB_STATUS_INPUT_BASE,
1346 		.limit = pin_limit_attrs,
1347 		.nlimit = ARRAY_SIZE(pin_limit_attrs),
1348 	}, {
1349 		.reg = PMBUS_READ_POUT,
1350 		.class = PSC_POWER,
1351 		.label = "pout",
1352 		.paged = true,
1353 		.func = PMBUS_HAVE_POUT,
1354 		.sfunc = PMBUS_HAVE_STATUS_IOUT,
1355 		.sbase = PB_STATUS_IOUT_BASE,
1356 		.limit = pout_limit_attrs,
1357 		.nlimit = ARRAY_SIZE(pout_limit_attrs),
1358 	}
1359 };
1360 
1361 /* Temperature atributes */
1362 
1363 static const struct pmbus_limit_attr temp_limit_attrs[] = {
1364 	{
1365 		.reg = PMBUS_UT_WARN_LIMIT,
1366 		.low = true,
1367 		.attr = "min",
1368 		.alarm = "min_alarm",
1369 		.sbit = PB_TEMP_UT_WARNING,
1370 	}, {
1371 		.reg = PMBUS_UT_FAULT_LIMIT,
1372 		.low = true,
1373 		.attr = "lcrit",
1374 		.alarm = "lcrit_alarm",
1375 		.sbit = PB_TEMP_UT_FAULT,
1376 	}, {
1377 		.reg = PMBUS_OT_WARN_LIMIT,
1378 		.attr = "max",
1379 		.alarm = "max_alarm",
1380 		.sbit = PB_TEMP_OT_WARNING,
1381 	}, {
1382 		.reg = PMBUS_OT_FAULT_LIMIT,
1383 		.attr = "crit",
1384 		.alarm = "crit_alarm",
1385 		.sbit = PB_TEMP_OT_FAULT,
1386 	}, {
1387 		.reg = PMBUS_VIRT_READ_TEMP_MIN,
1388 		.attr = "lowest",
1389 	}, {
1390 		.reg = PMBUS_VIRT_READ_TEMP_AVG,
1391 		.attr = "average",
1392 	}, {
1393 		.reg = PMBUS_VIRT_READ_TEMP_MAX,
1394 		.attr = "highest",
1395 	}, {
1396 		.reg = PMBUS_VIRT_RESET_TEMP_HISTORY,
1397 		.attr = "reset_history",
1398 	}
1399 };
1400 
1401 static const struct pmbus_limit_attr temp_limit_attrs2[] = {
1402 	{
1403 		.reg = PMBUS_UT_WARN_LIMIT,
1404 		.low = true,
1405 		.attr = "min",
1406 		.alarm = "min_alarm",
1407 		.sbit = PB_TEMP_UT_WARNING,
1408 	}, {
1409 		.reg = PMBUS_UT_FAULT_LIMIT,
1410 		.low = true,
1411 		.attr = "lcrit",
1412 		.alarm = "lcrit_alarm",
1413 		.sbit = PB_TEMP_UT_FAULT,
1414 	}, {
1415 		.reg = PMBUS_OT_WARN_LIMIT,
1416 		.attr = "max",
1417 		.alarm = "max_alarm",
1418 		.sbit = PB_TEMP_OT_WARNING,
1419 	}, {
1420 		.reg = PMBUS_OT_FAULT_LIMIT,
1421 		.attr = "crit",
1422 		.alarm = "crit_alarm",
1423 		.sbit = PB_TEMP_OT_FAULT,
1424 	}, {
1425 		.reg = PMBUS_VIRT_READ_TEMP2_MIN,
1426 		.attr = "lowest",
1427 	}, {
1428 		.reg = PMBUS_VIRT_READ_TEMP2_AVG,
1429 		.attr = "average",
1430 	}, {
1431 		.reg = PMBUS_VIRT_READ_TEMP2_MAX,
1432 		.attr = "highest",
1433 	}, {
1434 		.reg = PMBUS_VIRT_RESET_TEMP2_HISTORY,
1435 		.attr = "reset_history",
1436 	}
1437 };
1438 
1439 static const struct pmbus_limit_attr temp_limit_attrs3[] = {
1440 	{
1441 		.reg = PMBUS_UT_WARN_LIMIT,
1442 		.low = true,
1443 		.attr = "min",
1444 		.alarm = "min_alarm",
1445 		.sbit = PB_TEMP_UT_WARNING,
1446 	}, {
1447 		.reg = PMBUS_UT_FAULT_LIMIT,
1448 		.low = true,
1449 		.attr = "lcrit",
1450 		.alarm = "lcrit_alarm",
1451 		.sbit = PB_TEMP_UT_FAULT,
1452 	}, {
1453 		.reg = PMBUS_OT_WARN_LIMIT,
1454 		.attr = "max",
1455 		.alarm = "max_alarm",
1456 		.sbit = PB_TEMP_OT_WARNING,
1457 	}, {
1458 		.reg = PMBUS_OT_FAULT_LIMIT,
1459 		.attr = "crit",
1460 		.alarm = "crit_alarm",
1461 		.sbit = PB_TEMP_OT_FAULT,
1462 	}
1463 };
1464 
1465 static const struct pmbus_sensor_attr temp_attributes[] = {
1466 	{
1467 		.reg = PMBUS_READ_TEMPERATURE_1,
1468 		.class = PSC_TEMPERATURE,
1469 		.paged = true,
1470 		.update = true,
1471 		.compare = true,
1472 		.func = PMBUS_HAVE_TEMP,
1473 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1474 		.sbase = PB_STATUS_TEMP_BASE,
1475 		.gbit = PB_STATUS_TEMPERATURE,
1476 		.limit = temp_limit_attrs,
1477 		.nlimit = ARRAY_SIZE(temp_limit_attrs),
1478 	}, {
1479 		.reg = PMBUS_READ_TEMPERATURE_2,
1480 		.class = PSC_TEMPERATURE,
1481 		.paged = true,
1482 		.update = true,
1483 		.compare = true,
1484 		.func = PMBUS_HAVE_TEMP2,
1485 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1486 		.sbase = PB_STATUS_TEMP_BASE,
1487 		.gbit = PB_STATUS_TEMPERATURE,
1488 		.limit = temp_limit_attrs2,
1489 		.nlimit = ARRAY_SIZE(temp_limit_attrs2),
1490 	}, {
1491 		.reg = PMBUS_READ_TEMPERATURE_3,
1492 		.class = PSC_TEMPERATURE,
1493 		.paged = true,
1494 		.update = true,
1495 		.compare = true,
1496 		.func = PMBUS_HAVE_TEMP3,
1497 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1498 		.sbase = PB_STATUS_TEMP_BASE,
1499 		.gbit = PB_STATUS_TEMPERATURE,
1500 		.limit = temp_limit_attrs3,
1501 		.nlimit = ARRAY_SIZE(temp_limit_attrs3),
1502 	}
1503 };
1504 
1505 static const int pmbus_fan_registers[] = {
1506 	PMBUS_READ_FAN_SPEED_1,
1507 	PMBUS_READ_FAN_SPEED_2,
1508 	PMBUS_READ_FAN_SPEED_3,
1509 	PMBUS_READ_FAN_SPEED_4
1510 };
1511 
1512 static const int pmbus_fan_config_registers[] = {
1513 	PMBUS_FAN_CONFIG_12,
1514 	PMBUS_FAN_CONFIG_12,
1515 	PMBUS_FAN_CONFIG_34,
1516 	PMBUS_FAN_CONFIG_34
1517 };
1518 
1519 static const int pmbus_fan_status_registers[] = {
1520 	PMBUS_STATUS_FAN_12,
1521 	PMBUS_STATUS_FAN_12,
1522 	PMBUS_STATUS_FAN_34,
1523 	PMBUS_STATUS_FAN_34
1524 };
1525 
1526 static const u32 pmbus_fan_flags[] = {
1527 	PMBUS_HAVE_FAN12,
1528 	PMBUS_HAVE_FAN12,
1529 	PMBUS_HAVE_FAN34,
1530 	PMBUS_HAVE_FAN34
1531 };
1532 
1533 static const u32 pmbus_fan_status_flags[] = {
1534 	PMBUS_HAVE_STATUS_FAN12,
1535 	PMBUS_HAVE_STATUS_FAN12,
1536 	PMBUS_HAVE_STATUS_FAN34,
1537 	PMBUS_HAVE_STATUS_FAN34
1538 };
1539 
1540 /* Fans */
1541 static int pmbus_add_fan_attributes(struct i2c_client *client,
1542 				    struct pmbus_data *data)
1543 {
1544 	const struct pmbus_driver_info *info = data->info;
1545 	int index = 1;
1546 	int page;
1547 	int ret;
1548 
1549 	for (page = 0; page < info->pages; page++) {
1550 		int f;
1551 
1552 		for (f = 0; f < ARRAY_SIZE(pmbus_fan_registers); f++) {
1553 			int regval;
1554 
1555 			if (!(info->func[page] & pmbus_fan_flags[f]))
1556 				break;
1557 
1558 			if (!pmbus_check_word_register(client, page,
1559 						       pmbus_fan_registers[f]))
1560 				break;
1561 
1562 			/*
1563 			 * Skip fan if not installed.
1564 			 * Each fan configuration register covers multiple fans,
1565 			 * so we have to do some magic.
1566 			 */
1567 			regval = _pmbus_read_byte_data(client, page,
1568 				pmbus_fan_config_registers[f]);
1569 			if (regval < 0 ||
1570 			    (!(regval & (PB_FAN_1_INSTALLED >> ((f & 1) * 4)))))
1571 				continue;
1572 
1573 			if (pmbus_add_sensor(data, "fan", "input", index,
1574 					     page, pmbus_fan_registers[f],
1575 					     PSC_FAN, true, true) == NULL)
1576 				return -ENOMEM;
1577 
1578 			/*
1579 			 * Each fan status register covers multiple fans,
1580 			 * so we have to do some magic.
1581 			 */
1582 			if ((info->func[page] & pmbus_fan_status_flags[f]) &&
1583 			    pmbus_check_byte_register(client,
1584 					page, pmbus_fan_status_registers[f])) {
1585 				int base;
1586 
1587 				if (f > 1)	/* fan 3, 4 */
1588 					base = PB_STATUS_FAN34_BASE + page;
1589 				else
1590 					base = PB_STATUS_FAN_BASE + page;
1591 				ret = pmbus_add_boolean(data, "fan",
1592 					"alarm", index, NULL, NULL, base,
1593 					PB_FAN_FAN1_WARNING >> (f & 1));
1594 				if (ret)
1595 					return ret;
1596 				ret = pmbus_add_boolean(data, "fan",
1597 					"fault", index, NULL, NULL, base,
1598 					PB_FAN_FAN1_FAULT >> (f & 1));
1599 				if (ret)
1600 					return ret;
1601 			}
1602 			index++;
1603 		}
1604 	}
1605 	return 0;
1606 }
1607 
1608 static int pmbus_find_attributes(struct i2c_client *client,
1609 				 struct pmbus_data *data)
1610 {
1611 	int ret;
1612 
1613 	/* Voltage sensors */
1614 	ret = pmbus_add_sensor_attrs(client, data, "in", voltage_attributes,
1615 				     ARRAY_SIZE(voltage_attributes));
1616 	if (ret)
1617 		return ret;
1618 
1619 	/* Current sensors */
1620 	ret = pmbus_add_sensor_attrs(client, data, "curr", current_attributes,
1621 				     ARRAY_SIZE(current_attributes));
1622 	if (ret)
1623 		return ret;
1624 
1625 	/* Power sensors */
1626 	ret = pmbus_add_sensor_attrs(client, data, "power", power_attributes,
1627 				     ARRAY_SIZE(power_attributes));
1628 	if (ret)
1629 		return ret;
1630 
1631 	/* Temperature sensors */
1632 	ret = pmbus_add_sensor_attrs(client, data, "temp", temp_attributes,
1633 				     ARRAY_SIZE(temp_attributes));
1634 	if (ret)
1635 		return ret;
1636 
1637 	/* Fans */
1638 	ret = pmbus_add_fan_attributes(client, data);
1639 	return ret;
1640 }
1641 
1642 /*
1643  * Identify chip parameters.
1644  * This function is called for all chips.
1645  */
1646 static int pmbus_identify_common(struct i2c_client *client,
1647 				 struct pmbus_data *data, int page)
1648 {
1649 	int vout_mode = -1;
1650 
1651 	if (pmbus_check_byte_register(client, page, PMBUS_VOUT_MODE))
1652 		vout_mode = _pmbus_read_byte_data(client, page,
1653 						  PMBUS_VOUT_MODE);
1654 	if (vout_mode >= 0 && vout_mode != 0xff) {
1655 		/*
1656 		 * Not all chips support the VOUT_MODE command,
1657 		 * so a failure to read it is not an error.
1658 		 */
1659 		switch (vout_mode >> 5) {
1660 		case 0:	/* linear mode      */
1661 			if (data->info->format[PSC_VOLTAGE_OUT] != linear)
1662 				return -ENODEV;
1663 
1664 			data->exponent[page] = ((s8)(vout_mode << 3)) >> 3;
1665 			break;
1666 		case 1: /* VID mode         */
1667 			if (data->info->format[PSC_VOLTAGE_OUT] != vid)
1668 				return -ENODEV;
1669 			break;
1670 		case 2:	/* direct mode      */
1671 			if (data->info->format[PSC_VOLTAGE_OUT] != direct)
1672 				return -ENODEV;
1673 			break;
1674 		default:
1675 			return -ENODEV;
1676 		}
1677 	}
1678 
1679 	pmbus_clear_fault_page(client, page);
1680 	return 0;
1681 }
1682 
1683 static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data,
1684 			     struct pmbus_driver_info *info)
1685 {
1686 	struct device *dev = &client->dev;
1687 	int page, ret;
1688 
1689 	/*
1690 	 * Some PMBus chips don't support PMBUS_STATUS_BYTE, so try
1691 	 * to use PMBUS_STATUS_WORD instead if that is the case.
1692 	 * Bail out if both registers are not supported.
1693 	 */
1694 	data->status_register = PMBUS_STATUS_BYTE;
1695 	ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE);
1696 	if (ret < 0 || ret == 0xff) {
1697 		data->status_register = PMBUS_STATUS_WORD;
1698 		ret = i2c_smbus_read_word_data(client, PMBUS_STATUS_WORD);
1699 		if (ret < 0 || ret == 0xffff) {
1700 			dev_err(dev, "PMBus status register not found\n");
1701 			return -ENODEV;
1702 		}
1703 	}
1704 
1705 	pmbus_clear_faults(client);
1706 
1707 	if (info->identify) {
1708 		ret = (*info->identify)(client, info);
1709 		if (ret < 0) {
1710 			dev_err(dev, "Chip identification failed\n");
1711 			return ret;
1712 		}
1713 	}
1714 
1715 	if (info->pages <= 0 || info->pages > PMBUS_PAGES) {
1716 		dev_err(dev, "Bad number of PMBus pages: %d\n", info->pages);
1717 		return -ENODEV;
1718 	}
1719 
1720 	for (page = 0; page < info->pages; page++) {
1721 		ret = pmbus_identify_common(client, data, page);
1722 		if (ret < 0) {
1723 			dev_err(dev, "Failed to identify chip capabilities\n");
1724 			return ret;
1725 		}
1726 	}
1727 	return 0;
1728 }
1729 
1730 int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
1731 		   struct pmbus_driver_info *info)
1732 {
1733 	struct device *dev = &client->dev;
1734 	const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
1735 	struct pmbus_data *data;
1736 	int ret;
1737 
1738 	if (!info)
1739 		return -ENODEV;
1740 
1741 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE
1742 				     | I2C_FUNC_SMBUS_BYTE_DATA
1743 				     | I2C_FUNC_SMBUS_WORD_DATA))
1744 		return -ENODEV;
1745 
1746 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
1747 	if (!data)
1748 		return -ENOMEM;
1749 
1750 	i2c_set_clientdata(client, data);
1751 	mutex_init(&data->update_lock);
1752 	data->dev = dev;
1753 
1754 	if (pdata)
1755 		data->flags = pdata->flags;
1756 	data->info = info;
1757 
1758 	ret = pmbus_init_common(client, data, info);
1759 	if (ret < 0)
1760 		return ret;
1761 
1762 	ret = pmbus_find_attributes(client, data);
1763 	if (ret)
1764 		goto out_kfree;
1765 
1766 	/*
1767 	 * If there are no attributes, something is wrong.
1768 	 * Bail out instead of trying to register nothing.
1769 	 */
1770 	if (!data->num_attributes) {
1771 		dev_err(dev, "No attributes found\n");
1772 		ret = -ENODEV;
1773 		goto out_kfree;
1774 	}
1775 
1776 	data->groups[0] = &data->group;
1777 	data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
1778 							    data, data->groups);
1779 	if (IS_ERR(data->hwmon_dev)) {
1780 		ret = PTR_ERR(data->hwmon_dev);
1781 		dev_err(dev, "Failed to register hwmon device\n");
1782 		goto out_kfree;
1783 	}
1784 	return 0;
1785 
1786 out_kfree:
1787 	kfree(data->group.attrs);
1788 	return ret;
1789 }
1790 EXPORT_SYMBOL_GPL(pmbus_do_probe);
1791 
1792 int pmbus_do_remove(struct i2c_client *client)
1793 {
1794 	struct pmbus_data *data = i2c_get_clientdata(client);
1795 	hwmon_device_unregister(data->hwmon_dev);
1796 	kfree(data->group.attrs);
1797 	return 0;
1798 }
1799 EXPORT_SYMBOL_GPL(pmbus_do_remove);
1800 
1801 MODULE_AUTHOR("Guenter Roeck");
1802 MODULE_DESCRIPTION("PMBus core driver");
1803 MODULE_LICENSE("GPL");
1804