xref: /openbmc/linux/drivers/hwmon/pmbus/pmbus_core.c (revision 82e6fdd6)
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/debugfs.h>
23 #include <linux/kernel.h>
24 #include <linux/math64.h>
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/err.h>
28 #include <linux/slab.h>
29 #include <linux/i2c.h>
30 #include <linux/hwmon.h>
31 #include <linux/hwmon-sysfs.h>
32 #include <linux/jiffies.h>
33 #include <linux/pmbus.h>
34 #include <linux/regulator/driver.h>
35 #include <linux/regulator/machine.h>
36 #include "pmbus.h"
37 
38 /*
39  * Number of additional attribute pointers to allocate
40  * with each call to krealloc
41  */
42 #define PMBUS_ATTR_ALLOC_SIZE	32
43 
44 /*
45  * Index into status register array, per status register group
46  */
47 #define PB_STATUS_BASE		0
48 #define PB_STATUS_VOUT_BASE	(PB_STATUS_BASE + PMBUS_PAGES)
49 #define PB_STATUS_IOUT_BASE	(PB_STATUS_VOUT_BASE + PMBUS_PAGES)
50 #define PB_STATUS_FAN_BASE	(PB_STATUS_IOUT_BASE + PMBUS_PAGES)
51 #define PB_STATUS_FAN34_BASE	(PB_STATUS_FAN_BASE + PMBUS_PAGES)
52 #define PB_STATUS_TEMP_BASE	(PB_STATUS_FAN34_BASE + PMBUS_PAGES)
53 #define PB_STATUS_INPUT_BASE	(PB_STATUS_TEMP_BASE + PMBUS_PAGES)
54 #define PB_STATUS_VMON_BASE	(PB_STATUS_INPUT_BASE + 1)
55 
56 #define PB_NUM_STATUS_REG	(PB_STATUS_VMON_BASE + 1)
57 
58 #define PMBUS_NAME_SIZE		24
59 
60 struct pmbus_sensor {
61 	struct pmbus_sensor *next;
62 	char name[PMBUS_NAME_SIZE];	/* sysfs sensor name */
63 	struct device_attribute attribute;
64 	u8 page;		/* page number */
65 	u16 reg;		/* register */
66 	enum pmbus_sensor_classes class;	/* sensor class */
67 	bool update;		/* runtime sensor update needed */
68 	bool convert;		/* Whether or not to apply linear/vid/direct */
69 	int data;		/* Sensor data.
70 				   Negative if there was a read error */
71 };
72 #define to_pmbus_sensor(_attr) \
73 	container_of(_attr, struct pmbus_sensor, attribute)
74 
75 struct pmbus_boolean {
76 	char name[PMBUS_NAME_SIZE];	/* sysfs boolean name */
77 	struct sensor_device_attribute attribute;
78 	struct pmbus_sensor *s1;
79 	struct pmbus_sensor *s2;
80 };
81 #define to_pmbus_boolean(_attr) \
82 	container_of(_attr, struct pmbus_boolean, attribute)
83 
84 struct pmbus_label {
85 	char name[PMBUS_NAME_SIZE];	/* sysfs label name */
86 	struct device_attribute attribute;
87 	char label[PMBUS_NAME_SIZE];	/* label */
88 };
89 #define to_pmbus_label(_attr) \
90 	container_of(_attr, struct pmbus_label, attribute)
91 
92 struct pmbus_data {
93 	struct device *dev;
94 	struct device *hwmon_dev;
95 
96 	u32 flags;		/* from platform data */
97 
98 	int exponent[PMBUS_PAGES];
99 				/* linear mode: exponent for output voltages */
100 
101 	const struct pmbus_driver_info *info;
102 
103 	int max_attributes;
104 	int num_attributes;
105 	struct attribute_group group;
106 	const struct attribute_group *groups[2];
107 	struct dentry *debugfs;		/* debugfs device directory */
108 
109 	struct pmbus_sensor *sensors;
110 
111 	struct mutex update_lock;
112 	bool valid;
113 	unsigned long last_updated;	/* in jiffies */
114 
115 	/*
116 	 * A single status register covers multiple attributes,
117 	 * so we keep them all together.
118 	 */
119 	u16 status[PB_NUM_STATUS_REG];
120 
121 	bool has_status_word;		/* device uses STATUS_WORD register */
122 	int (*read_status)(struct i2c_client *client, int page);
123 
124 	u8 currpage;
125 };
126 
127 struct pmbus_debugfs_entry {
128 	struct i2c_client *client;
129 	u8 page;
130 	u8 reg;
131 };
132 
133 static const int pmbus_fan_rpm_mask[] = {
134 	PB_FAN_1_RPM,
135 	PB_FAN_2_RPM,
136 	PB_FAN_1_RPM,
137 	PB_FAN_2_RPM,
138 };
139 
140 static const int pmbus_fan_config_registers[] = {
141 	PMBUS_FAN_CONFIG_12,
142 	PMBUS_FAN_CONFIG_12,
143 	PMBUS_FAN_CONFIG_34,
144 	PMBUS_FAN_CONFIG_34
145 };
146 
147 static const int pmbus_fan_command_registers[] = {
148 	PMBUS_FAN_COMMAND_1,
149 	PMBUS_FAN_COMMAND_2,
150 	PMBUS_FAN_COMMAND_3,
151 	PMBUS_FAN_COMMAND_4,
152 };
153 
154 void pmbus_clear_cache(struct i2c_client *client)
155 {
156 	struct pmbus_data *data = i2c_get_clientdata(client);
157 
158 	data->valid = false;
159 }
160 EXPORT_SYMBOL_GPL(pmbus_clear_cache);
161 
162 int pmbus_set_page(struct i2c_client *client, int page)
163 {
164 	struct pmbus_data *data = i2c_get_clientdata(client);
165 	int rv;
166 
167 	if (page < 0 || page == data->currpage)
168 		return 0;
169 
170 	if (!(data->info->func[page] & PMBUS_PAGE_VIRTUAL)) {
171 		rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
172 		if (rv < 0)
173 			return rv;
174 
175 		rv = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
176 		if (rv < 0)
177 			return rv;
178 
179 		if (rv != page)
180 			return -EIO;
181 	}
182 
183 	data->currpage = page;
184 
185 	return 0;
186 }
187 EXPORT_SYMBOL_GPL(pmbus_set_page);
188 
189 int pmbus_write_byte(struct i2c_client *client, int page, u8 value)
190 {
191 	int rv;
192 
193 	rv = pmbus_set_page(client, page);
194 	if (rv < 0)
195 		return rv;
196 
197 	return i2c_smbus_write_byte(client, value);
198 }
199 EXPORT_SYMBOL_GPL(pmbus_write_byte);
200 
201 /*
202  * _pmbus_write_byte() is similar to pmbus_write_byte(), but checks if
203  * a device specific mapping function exists and calls it if necessary.
204  */
205 static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value)
206 {
207 	struct pmbus_data *data = i2c_get_clientdata(client);
208 	const struct pmbus_driver_info *info = data->info;
209 	int status;
210 
211 	if (info->write_byte) {
212 		status = info->write_byte(client, page, value);
213 		if (status != -ENODATA)
214 			return status;
215 	}
216 	return pmbus_write_byte(client, page, value);
217 }
218 
219 int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg,
220 			  u16 word)
221 {
222 	int rv;
223 
224 	rv = pmbus_set_page(client, page);
225 	if (rv < 0)
226 		return rv;
227 
228 	return i2c_smbus_write_word_data(client, reg, word);
229 }
230 EXPORT_SYMBOL_GPL(pmbus_write_word_data);
231 
232 
233 static int pmbus_write_virt_reg(struct i2c_client *client, int page, int reg,
234 				u16 word)
235 {
236 	int bit;
237 	int id;
238 	int rv;
239 
240 	switch (reg) {
241 	case PMBUS_VIRT_FAN_TARGET_1 ... PMBUS_VIRT_FAN_TARGET_4:
242 		id = reg - PMBUS_VIRT_FAN_TARGET_1;
243 		bit = pmbus_fan_rpm_mask[id];
244 		rv = pmbus_update_fan(client, page, id, bit, bit, word);
245 		break;
246 	default:
247 		rv = -ENXIO;
248 		break;
249 	}
250 
251 	return rv;
252 }
253 
254 /*
255  * _pmbus_write_word_data() is similar to pmbus_write_word_data(), but checks if
256  * a device specific mapping function exists and calls it if necessary.
257  */
258 static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg,
259 				  u16 word)
260 {
261 	struct pmbus_data *data = i2c_get_clientdata(client);
262 	const struct pmbus_driver_info *info = data->info;
263 	int status;
264 
265 	if (info->write_word_data) {
266 		status = info->write_word_data(client, page, reg, word);
267 		if (status != -ENODATA)
268 			return status;
269 	}
270 
271 	if (reg >= PMBUS_VIRT_BASE)
272 		return pmbus_write_virt_reg(client, page, reg, word);
273 
274 	return pmbus_write_word_data(client, page, reg, word);
275 }
276 
277 int pmbus_update_fan(struct i2c_client *client, int page, int id,
278 		     u8 config, u8 mask, u16 command)
279 {
280 	int from;
281 	int rv;
282 	u8 to;
283 
284 	from = pmbus_read_byte_data(client, page,
285 				    pmbus_fan_config_registers[id]);
286 	if (from < 0)
287 		return from;
288 
289 	to = (from & ~mask) | (config & mask);
290 	if (to != from) {
291 		rv = pmbus_write_byte_data(client, page,
292 					   pmbus_fan_config_registers[id], to);
293 		if (rv < 0)
294 			return rv;
295 	}
296 
297 	return _pmbus_write_word_data(client, page,
298 				      pmbus_fan_command_registers[id], command);
299 }
300 EXPORT_SYMBOL_GPL(pmbus_update_fan);
301 
302 int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg)
303 {
304 	int rv;
305 
306 	rv = pmbus_set_page(client, page);
307 	if (rv < 0)
308 		return rv;
309 
310 	return i2c_smbus_read_word_data(client, reg);
311 }
312 EXPORT_SYMBOL_GPL(pmbus_read_word_data);
313 
314 static int pmbus_read_virt_reg(struct i2c_client *client, int page, int reg)
315 {
316 	int rv;
317 	int id;
318 
319 	switch (reg) {
320 	case PMBUS_VIRT_FAN_TARGET_1 ... PMBUS_VIRT_FAN_TARGET_4:
321 		id = reg - PMBUS_VIRT_FAN_TARGET_1;
322 		rv = pmbus_get_fan_rate_device(client, page, id, rpm);
323 		break;
324 	default:
325 		rv = -ENXIO;
326 		break;
327 	}
328 
329 	return rv;
330 }
331 
332 /*
333  * _pmbus_read_word_data() is similar to pmbus_read_word_data(), but checks if
334  * a device specific mapping function exists and calls it if necessary.
335  */
336 static int _pmbus_read_word_data(struct i2c_client *client, int page, int reg)
337 {
338 	struct pmbus_data *data = i2c_get_clientdata(client);
339 	const struct pmbus_driver_info *info = data->info;
340 	int status;
341 
342 	if (info->read_word_data) {
343 		status = info->read_word_data(client, page, reg);
344 		if (status != -ENODATA)
345 			return status;
346 	}
347 
348 	if (reg >= PMBUS_VIRT_BASE)
349 		return pmbus_read_virt_reg(client, page, reg);
350 
351 	return pmbus_read_word_data(client, page, reg);
352 }
353 
354 int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg)
355 {
356 	int rv;
357 
358 	rv = pmbus_set_page(client, page);
359 	if (rv < 0)
360 		return rv;
361 
362 	return i2c_smbus_read_byte_data(client, reg);
363 }
364 EXPORT_SYMBOL_GPL(pmbus_read_byte_data);
365 
366 int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value)
367 {
368 	int rv;
369 
370 	rv = pmbus_set_page(client, page);
371 	if (rv < 0)
372 		return rv;
373 
374 	return i2c_smbus_write_byte_data(client, reg, value);
375 }
376 EXPORT_SYMBOL_GPL(pmbus_write_byte_data);
377 
378 int pmbus_update_byte_data(struct i2c_client *client, int page, u8 reg,
379 			   u8 mask, u8 value)
380 {
381 	unsigned int tmp;
382 	int rv;
383 
384 	rv = pmbus_read_byte_data(client, page, reg);
385 	if (rv < 0)
386 		return rv;
387 
388 	tmp = (rv & ~mask) | (value & mask);
389 
390 	if (tmp != rv)
391 		rv = pmbus_write_byte_data(client, page, reg, tmp);
392 
393 	return rv;
394 }
395 EXPORT_SYMBOL_GPL(pmbus_update_byte_data);
396 
397 /*
398  * _pmbus_read_byte_data() is similar to pmbus_read_byte_data(), but checks if
399  * a device specific mapping function exists and calls it if necessary.
400  */
401 static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
402 {
403 	struct pmbus_data *data = i2c_get_clientdata(client);
404 	const struct pmbus_driver_info *info = data->info;
405 	int status;
406 
407 	if (info->read_byte_data) {
408 		status = info->read_byte_data(client, page, reg);
409 		if (status != -ENODATA)
410 			return status;
411 	}
412 	return pmbus_read_byte_data(client, page, reg);
413 }
414 
415 static struct pmbus_sensor *pmbus_find_sensor(struct pmbus_data *data, int page,
416 					      int reg)
417 {
418 	struct pmbus_sensor *sensor;
419 
420 	for (sensor = data->sensors; sensor; sensor = sensor->next) {
421 		if (sensor->page == page && sensor->reg == reg)
422 			return sensor;
423 	}
424 
425 	return ERR_PTR(-EINVAL);
426 }
427 
428 static int pmbus_get_fan_rate(struct i2c_client *client, int page, int id,
429 			      enum pmbus_fan_mode mode,
430 			      bool from_cache)
431 {
432 	struct pmbus_data *data = i2c_get_clientdata(client);
433 	bool want_rpm, have_rpm;
434 	struct pmbus_sensor *s;
435 	int config;
436 	int reg;
437 
438 	want_rpm = (mode == rpm);
439 
440 	if (from_cache) {
441 		reg = want_rpm ? PMBUS_VIRT_FAN_TARGET_1 : PMBUS_VIRT_PWM_1;
442 		s = pmbus_find_sensor(data, page, reg + id);
443 		if (IS_ERR(s))
444 			return PTR_ERR(s);
445 
446 		return s->data;
447 	}
448 
449 	config = pmbus_read_byte_data(client, page,
450 				      pmbus_fan_config_registers[id]);
451 	if (config < 0)
452 		return config;
453 
454 	have_rpm = !!(config & pmbus_fan_rpm_mask[id]);
455 	if (want_rpm == have_rpm)
456 		return pmbus_read_word_data(client, page,
457 					    pmbus_fan_command_registers[id]);
458 
459 	/* Can't sensibly map between RPM and PWM, just return zero */
460 	return 0;
461 }
462 
463 int pmbus_get_fan_rate_device(struct i2c_client *client, int page, int id,
464 			      enum pmbus_fan_mode mode)
465 {
466 	return pmbus_get_fan_rate(client, page, id, mode, false);
467 }
468 EXPORT_SYMBOL_GPL(pmbus_get_fan_rate_device);
469 
470 int pmbus_get_fan_rate_cached(struct i2c_client *client, int page, int id,
471 			      enum pmbus_fan_mode mode)
472 {
473 	return pmbus_get_fan_rate(client, page, id, mode, true);
474 }
475 EXPORT_SYMBOL_GPL(pmbus_get_fan_rate_cached);
476 
477 static void pmbus_clear_fault_page(struct i2c_client *client, int page)
478 {
479 	_pmbus_write_byte(client, page, PMBUS_CLEAR_FAULTS);
480 }
481 
482 void pmbus_clear_faults(struct i2c_client *client)
483 {
484 	struct pmbus_data *data = i2c_get_clientdata(client);
485 	int i;
486 
487 	for (i = 0; i < data->info->pages; i++)
488 		pmbus_clear_fault_page(client, i);
489 }
490 EXPORT_SYMBOL_GPL(pmbus_clear_faults);
491 
492 static int pmbus_check_status_cml(struct i2c_client *client)
493 {
494 	struct pmbus_data *data = i2c_get_clientdata(client);
495 	int status, status2;
496 
497 	status = data->read_status(client, -1);
498 	if (status < 0 || (status & PB_STATUS_CML)) {
499 		status2 = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML);
500 		if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND))
501 			return -EIO;
502 	}
503 	return 0;
504 }
505 
506 static bool pmbus_check_register(struct i2c_client *client,
507 				 int (*func)(struct i2c_client *client,
508 					     int page, int reg),
509 				 int page, int reg)
510 {
511 	int rv;
512 	struct pmbus_data *data = i2c_get_clientdata(client);
513 
514 	rv = func(client, page, reg);
515 	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
516 		rv = pmbus_check_status_cml(client);
517 	pmbus_clear_fault_page(client, -1);
518 	return rv >= 0;
519 }
520 
521 static bool pmbus_check_status_register(struct i2c_client *client, int page)
522 {
523 	int status;
524 	struct pmbus_data *data = i2c_get_clientdata(client);
525 
526 	status = data->read_status(client, page);
527 	if (status >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK) &&
528 	    (status & PB_STATUS_CML)) {
529 		status = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML);
530 		if (status < 0 || (status & PB_CML_FAULT_INVALID_COMMAND))
531 			status = -EIO;
532 	}
533 
534 	pmbus_clear_fault_page(client, -1);
535 	return status >= 0;
536 }
537 
538 bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg)
539 {
540 	return pmbus_check_register(client, _pmbus_read_byte_data, page, reg);
541 }
542 EXPORT_SYMBOL_GPL(pmbus_check_byte_register);
543 
544 bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
545 {
546 	return pmbus_check_register(client, _pmbus_read_word_data, page, reg);
547 }
548 EXPORT_SYMBOL_GPL(pmbus_check_word_register);
549 
550 const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
551 {
552 	struct pmbus_data *data = i2c_get_clientdata(client);
553 
554 	return data->info;
555 }
556 EXPORT_SYMBOL_GPL(pmbus_get_driver_info);
557 
558 static struct _pmbus_status {
559 	u32 func;
560 	u16 base;
561 	u16 reg;
562 } pmbus_status[] = {
563 	{ PMBUS_HAVE_STATUS_VOUT, PB_STATUS_VOUT_BASE, PMBUS_STATUS_VOUT },
564 	{ PMBUS_HAVE_STATUS_IOUT, PB_STATUS_IOUT_BASE, PMBUS_STATUS_IOUT },
565 	{ PMBUS_HAVE_STATUS_TEMP, PB_STATUS_TEMP_BASE,
566 	  PMBUS_STATUS_TEMPERATURE },
567 	{ PMBUS_HAVE_STATUS_FAN12, PB_STATUS_FAN_BASE, PMBUS_STATUS_FAN_12 },
568 	{ PMBUS_HAVE_STATUS_FAN34, PB_STATUS_FAN34_BASE, PMBUS_STATUS_FAN_34 },
569 };
570 
571 static struct pmbus_data *pmbus_update_device(struct device *dev)
572 {
573 	struct i2c_client *client = to_i2c_client(dev->parent);
574 	struct pmbus_data *data = i2c_get_clientdata(client);
575 	const struct pmbus_driver_info *info = data->info;
576 	struct pmbus_sensor *sensor;
577 
578 	mutex_lock(&data->update_lock);
579 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
580 		int i, j;
581 
582 		for (i = 0; i < info->pages; i++) {
583 			data->status[PB_STATUS_BASE + i]
584 			    = data->read_status(client, i);
585 			for (j = 0; j < ARRAY_SIZE(pmbus_status); j++) {
586 				struct _pmbus_status *s = &pmbus_status[j];
587 
588 				if (!(info->func[i] & s->func))
589 					continue;
590 				data->status[s->base + i]
591 					= _pmbus_read_byte_data(client, i,
592 								s->reg);
593 			}
594 		}
595 
596 		if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
597 			data->status[PB_STATUS_INPUT_BASE]
598 			  = _pmbus_read_byte_data(client, 0,
599 						  PMBUS_STATUS_INPUT);
600 
601 		if (info->func[0] & PMBUS_HAVE_STATUS_VMON)
602 			data->status[PB_STATUS_VMON_BASE]
603 			  = _pmbus_read_byte_data(client, 0,
604 						  PMBUS_VIRT_STATUS_VMON);
605 
606 		for (sensor = data->sensors; sensor; sensor = sensor->next) {
607 			if (!data->valid || sensor->update)
608 				sensor->data
609 				    = _pmbus_read_word_data(client,
610 							    sensor->page,
611 							    sensor->reg);
612 		}
613 		pmbus_clear_faults(client);
614 		data->last_updated = jiffies;
615 		data->valid = 1;
616 	}
617 	mutex_unlock(&data->update_lock);
618 	return data;
619 }
620 
621 /*
622  * Convert linear sensor values to milli- or micro-units
623  * depending on sensor type.
624  */
625 static long pmbus_reg2data_linear(struct pmbus_data *data,
626 				  struct pmbus_sensor *sensor)
627 {
628 	s16 exponent;
629 	s32 mantissa;
630 	long val;
631 
632 	if (sensor->class == PSC_VOLTAGE_OUT) {	/* LINEAR16 */
633 		exponent = data->exponent[sensor->page];
634 		mantissa = (u16) sensor->data;
635 	} else {				/* LINEAR11 */
636 		exponent = ((s16)sensor->data) >> 11;
637 		mantissa = ((s16)((sensor->data & 0x7ff) << 5)) >> 5;
638 	}
639 
640 	val = mantissa;
641 
642 	/* scale result to milli-units for all sensors except fans */
643 	if (sensor->class != PSC_FAN)
644 		val = val * 1000L;
645 
646 	/* scale result to micro-units for power sensors */
647 	if (sensor->class == PSC_POWER)
648 		val = val * 1000L;
649 
650 	if (exponent >= 0)
651 		val <<= exponent;
652 	else
653 		val >>= -exponent;
654 
655 	return val;
656 }
657 
658 /*
659  * Convert direct sensor values to milli- or micro-units
660  * depending on sensor type.
661  */
662 static long pmbus_reg2data_direct(struct pmbus_data *data,
663 				  struct pmbus_sensor *sensor)
664 {
665 	s64 b, val = (s16)sensor->data;
666 	s32 m, R;
667 
668 	m = data->info->m[sensor->class];
669 	b = data->info->b[sensor->class];
670 	R = data->info->R[sensor->class];
671 
672 	if (m == 0)
673 		return 0;
674 
675 	/* X = 1/m * (Y * 10^-R - b) */
676 	R = -R;
677 	/* scale result to milli-units for everything but fans */
678 	if (!(sensor->class == PSC_FAN || sensor->class == PSC_PWM)) {
679 		R += 3;
680 		b *= 1000;
681 	}
682 
683 	/* scale result to micro-units for power sensors */
684 	if (sensor->class == PSC_POWER) {
685 		R += 3;
686 		b *= 1000;
687 	}
688 
689 	while (R > 0) {
690 		val *= 10;
691 		R--;
692 	}
693 	while (R < 0) {
694 		val = div_s64(val + 5LL, 10L);  /* round closest */
695 		R++;
696 	}
697 
698 	val = div_s64(val - b, m);
699 	return clamp_val(val, LONG_MIN, LONG_MAX);
700 }
701 
702 /*
703  * Convert VID sensor values to milli- or micro-units
704  * depending on sensor type.
705  */
706 static long pmbus_reg2data_vid(struct pmbus_data *data,
707 			       struct pmbus_sensor *sensor)
708 {
709 	long val = sensor->data;
710 	long rv = 0;
711 
712 	switch (data->info->vrm_version) {
713 	case vr11:
714 		if (val >= 0x02 && val <= 0xb2)
715 			rv = DIV_ROUND_CLOSEST(160000 - (val - 2) * 625, 100);
716 		break;
717 	case vr12:
718 		if (val >= 0x01)
719 			rv = 250 + (val - 1) * 5;
720 		break;
721 	case vr13:
722 		if (val >= 0x01)
723 			rv = 500 + (val - 1) * 10;
724 		break;
725 	}
726 	return rv;
727 }
728 
729 static long pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
730 {
731 	long val;
732 
733 	if (!sensor->convert)
734 		return sensor->data;
735 
736 	switch (data->info->format[sensor->class]) {
737 	case direct:
738 		val = pmbus_reg2data_direct(data, sensor);
739 		break;
740 	case vid:
741 		val = pmbus_reg2data_vid(data, sensor);
742 		break;
743 	case linear:
744 	default:
745 		val = pmbus_reg2data_linear(data, sensor);
746 		break;
747 	}
748 	return val;
749 }
750 
751 #define MAX_MANTISSA	(1023 * 1000)
752 #define MIN_MANTISSA	(511 * 1000)
753 
754 static u16 pmbus_data2reg_linear(struct pmbus_data *data,
755 				 struct pmbus_sensor *sensor, long val)
756 {
757 	s16 exponent = 0, mantissa;
758 	bool negative = false;
759 
760 	/* simple case */
761 	if (val == 0)
762 		return 0;
763 
764 	if (sensor->class == PSC_VOLTAGE_OUT) {
765 		/* LINEAR16 does not support negative voltages */
766 		if (val < 0)
767 			return 0;
768 
769 		/*
770 		 * For a static exponents, we don't have a choice
771 		 * but to adjust the value to it.
772 		 */
773 		if (data->exponent[sensor->page] < 0)
774 			val <<= -data->exponent[sensor->page];
775 		else
776 			val >>= data->exponent[sensor->page];
777 		val = DIV_ROUND_CLOSEST(val, 1000);
778 		return val & 0xffff;
779 	}
780 
781 	if (val < 0) {
782 		negative = true;
783 		val = -val;
784 	}
785 
786 	/* Power is in uW. Convert to mW before converting. */
787 	if (sensor->class == PSC_POWER)
788 		val = DIV_ROUND_CLOSEST(val, 1000L);
789 
790 	/*
791 	 * For simplicity, convert fan data to milli-units
792 	 * before calculating the exponent.
793 	 */
794 	if (sensor->class == PSC_FAN)
795 		val = val * 1000;
796 
797 	/* Reduce large mantissa until it fits into 10 bit */
798 	while (val >= MAX_MANTISSA && exponent < 15) {
799 		exponent++;
800 		val >>= 1;
801 	}
802 	/* Increase small mantissa to improve precision */
803 	while (val < MIN_MANTISSA && exponent > -15) {
804 		exponent--;
805 		val <<= 1;
806 	}
807 
808 	/* Convert mantissa from milli-units to units */
809 	mantissa = DIV_ROUND_CLOSEST(val, 1000);
810 
811 	/* Ensure that resulting number is within range */
812 	if (mantissa > 0x3ff)
813 		mantissa = 0x3ff;
814 
815 	/* restore sign */
816 	if (negative)
817 		mantissa = -mantissa;
818 
819 	/* Convert to 5 bit exponent, 11 bit mantissa */
820 	return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
821 }
822 
823 static u16 pmbus_data2reg_direct(struct pmbus_data *data,
824 				 struct pmbus_sensor *sensor, long val)
825 {
826 	s64 b, val64 = val;
827 	s32 m, R;
828 
829 	m = data->info->m[sensor->class];
830 	b = data->info->b[sensor->class];
831 	R = data->info->R[sensor->class];
832 
833 	/* Power is in uW. Adjust R and b. */
834 	if (sensor->class == PSC_POWER) {
835 		R -= 3;
836 		b *= 1000;
837 	}
838 
839 	/* Calculate Y = (m * X + b) * 10^R */
840 	if (!(sensor->class == PSC_FAN || sensor->class == PSC_PWM)) {
841 		R -= 3;		/* Adjust R and b for data in milli-units */
842 		b *= 1000;
843 	}
844 	val64 = val64 * m + b;
845 
846 	while (R > 0) {
847 		val64 *= 10;
848 		R--;
849 	}
850 	while (R < 0) {
851 		val64 = div_s64(val64 + 5LL, 10L);  /* round closest */
852 		R++;
853 	}
854 
855 	return (u16)clamp_val(val64, S16_MIN, S16_MAX);
856 }
857 
858 static u16 pmbus_data2reg_vid(struct pmbus_data *data,
859 			      struct pmbus_sensor *sensor, long val)
860 {
861 	val = clamp_val(val, 500, 1600);
862 
863 	return 2 + DIV_ROUND_CLOSEST((1600 - val) * 100, 625);
864 }
865 
866 static u16 pmbus_data2reg(struct pmbus_data *data,
867 			  struct pmbus_sensor *sensor, long val)
868 {
869 	u16 regval;
870 
871 	if (!sensor->convert)
872 		return val;
873 
874 	switch (data->info->format[sensor->class]) {
875 	case direct:
876 		regval = pmbus_data2reg_direct(data, sensor, val);
877 		break;
878 	case vid:
879 		regval = pmbus_data2reg_vid(data, sensor, val);
880 		break;
881 	case linear:
882 	default:
883 		regval = pmbus_data2reg_linear(data, sensor, val);
884 		break;
885 	}
886 	return regval;
887 }
888 
889 /*
890  * Return boolean calculated from converted data.
891  * <index> defines a status register index and mask.
892  * The mask is in the lower 8 bits, the register index is in bits 8..23.
893  *
894  * The associated pmbus_boolean structure contains optional pointers to two
895  * sensor attributes. If specified, those attributes are compared against each
896  * other to determine if a limit has been exceeded.
897  *
898  * If the sensor attribute pointers are NULL, the function returns true if
899  * (status[reg] & mask) is true.
900  *
901  * If sensor attribute pointers are provided, a comparison against a specified
902  * limit has to be performed to determine the boolean result.
903  * In this case, the function returns true if v1 >= v2 (where v1 and v2 are
904  * sensor values referenced by sensor attribute pointers s1 and s2).
905  *
906  * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>.
907  * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>.
908  *
909  * If a negative value is stored in any of the referenced registers, this value
910  * reflects an error code which will be returned.
911  */
912 static int pmbus_get_boolean(struct pmbus_data *data, struct pmbus_boolean *b,
913 			     int index)
914 {
915 	struct pmbus_sensor *s1 = b->s1;
916 	struct pmbus_sensor *s2 = b->s2;
917 	u16 reg = (index >> 16) & 0xffff;
918 	u16 mask = index & 0xffff;
919 	int ret, status;
920 	u16 regval;
921 
922 	status = data->status[reg];
923 	if (status < 0)
924 		return status;
925 
926 	regval = status & mask;
927 	if (!s1 && !s2) {
928 		ret = !!regval;
929 	} else if (!s1 || !s2) {
930 		WARN(1, "Bad boolean descriptor %p: s1=%p, s2=%p\n", b, s1, s2);
931 		return 0;
932 	} else {
933 		long v1, v2;
934 
935 		if (s1->data < 0)
936 			return s1->data;
937 		if (s2->data < 0)
938 			return s2->data;
939 
940 		v1 = pmbus_reg2data(data, s1);
941 		v2 = pmbus_reg2data(data, s2);
942 		ret = !!(regval && v1 >= v2);
943 	}
944 	return ret;
945 }
946 
947 static ssize_t pmbus_show_boolean(struct device *dev,
948 				  struct device_attribute *da, char *buf)
949 {
950 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
951 	struct pmbus_boolean *boolean = to_pmbus_boolean(attr);
952 	struct pmbus_data *data = pmbus_update_device(dev);
953 	int val;
954 
955 	val = pmbus_get_boolean(data, boolean, attr->index);
956 	if (val < 0)
957 		return val;
958 	return snprintf(buf, PAGE_SIZE, "%d\n", val);
959 }
960 
961 static ssize_t pmbus_show_sensor(struct device *dev,
962 				 struct device_attribute *devattr, char *buf)
963 {
964 	struct pmbus_data *data = pmbus_update_device(dev);
965 	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
966 
967 	if (sensor->data < 0)
968 		return sensor->data;
969 
970 	return snprintf(buf, PAGE_SIZE, "%ld\n", pmbus_reg2data(data, sensor));
971 }
972 
973 static ssize_t pmbus_set_sensor(struct device *dev,
974 				struct device_attribute *devattr,
975 				const char *buf, size_t count)
976 {
977 	struct i2c_client *client = to_i2c_client(dev->parent);
978 	struct pmbus_data *data = i2c_get_clientdata(client);
979 	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
980 	ssize_t rv = count;
981 	long val = 0;
982 	int ret;
983 	u16 regval;
984 
985 	if (kstrtol(buf, 10, &val) < 0)
986 		return -EINVAL;
987 
988 	mutex_lock(&data->update_lock);
989 	regval = pmbus_data2reg(data, sensor, val);
990 	ret = _pmbus_write_word_data(client, sensor->page, sensor->reg, regval);
991 	if (ret < 0)
992 		rv = ret;
993 	else
994 		sensor->data = regval;
995 	mutex_unlock(&data->update_lock);
996 	return rv;
997 }
998 
999 static ssize_t pmbus_show_label(struct device *dev,
1000 				struct device_attribute *da, char *buf)
1001 {
1002 	struct pmbus_label *label = to_pmbus_label(da);
1003 
1004 	return snprintf(buf, PAGE_SIZE, "%s\n", label->label);
1005 }
1006 
1007 static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
1008 {
1009 	if (data->num_attributes >= data->max_attributes - 1) {
1010 		int new_max_attrs = data->max_attributes + PMBUS_ATTR_ALLOC_SIZE;
1011 		void *new_attrs = krealloc(data->group.attrs,
1012 					   new_max_attrs * sizeof(void *),
1013 					   GFP_KERNEL);
1014 		if (!new_attrs)
1015 			return -ENOMEM;
1016 		data->group.attrs = new_attrs;
1017 		data->max_attributes = new_max_attrs;
1018 	}
1019 
1020 	data->group.attrs[data->num_attributes++] = attr;
1021 	data->group.attrs[data->num_attributes] = NULL;
1022 	return 0;
1023 }
1024 
1025 static void pmbus_dev_attr_init(struct device_attribute *dev_attr,
1026 				const char *name,
1027 				umode_t mode,
1028 				ssize_t (*show)(struct device *dev,
1029 						struct device_attribute *attr,
1030 						char *buf),
1031 				ssize_t (*store)(struct device *dev,
1032 						 struct device_attribute *attr,
1033 						 const char *buf, size_t count))
1034 {
1035 	sysfs_attr_init(&dev_attr->attr);
1036 	dev_attr->attr.name = name;
1037 	dev_attr->attr.mode = mode;
1038 	dev_attr->show = show;
1039 	dev_attr->store = store;
1040 }
1041 
1042 static void pmbus_attr_init(struct sensor_device_attribute *a,
1043 			    const char *name,
1044 			    umode_t mode,
1045 			    ssize_t (*show)(struct device *dev,
1046 					    struct device_attribute *attr,
1047 					    char *buf),
1048 			    ssize_t (*store)(struct device *dev,
1049 					     struct device_attribute *attr,
1050 					     const char *buf, size_t count),
1051 			    int idx)
1052 {
1053 	pmbus_dev_attr_init(&a->dev_attr, name, mode, show, store);
1054 	a->index = idx;
1055 }
1056 
1057 static int pmbus_add_boolean(struct pmbus_data *data,
1058 			     const char *name, const char *type, int seq,
1059 			     struct pmbus_sensor *s1,
1060 			     struct pmbus_sensor *s2,
1061 			     u16 reg, u16 mask)
1062 {
1063 	struct pmbus_boolean *boolean;
1064 	struct sensor_device_attribute *a;
1065 
1066 	boolean = devm_kzalloc(data->dev, sizeof(*boolean), GFP_KERNEL);
1067 	if (!boolean)
1068 		return -ENOMEM;
1069 
1070 	a = &boolean->attribute;
1071 
1072 	snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
1073 		 name, seq, type);
1074 	boolean->s1 = s1;
1075 	boolean->s2 = s2;
1076 	pmbus_attr_init(a, boolean->name, S_IRUGO, pmbus_show_boolean, NULL,
1077 			(reg << 16) | mask);
1078 
1079 	return pmbus_add_attribute(data, &a->dev_attr.attr);
1080 }
1081 
1082 static struct pmbus_sensor *pmbus_add_sensor(struct pmbus_data *data,
1083 					     const char *name, const char *type,
1084 					     int seq, int page, int reg,
1085 					     enum pmbus_sensor_classes class,
1086 					     bool update, bool readonly,
1087 					     bool convert)
1088 {
1089 	struct pmbus_sensor *sensor;
1090 	struct device_attribute *a;
1091 
1092 	sensor = devm_kzalloc(data->dev, sizeof(*sensor), GFP_KERNEL);
1093 	if (!sensor)
1094 		return NULL;
1095 	a = &sensor->attribute;
1096 
1097 	if (type)
1098 		snprintf(sensor->name, sizeof(sensor->name), "%s%d_%s",
1099 			 name, seq, type);
1100 	else
1101 		snprintf(sensor->name, sizeof(sensor->name), "%s%d",
1102 			 name, seq);
1103 
1104 	sensor->page = page;
1105 	sensor->reg = reg;
1106 	sensor->class = class;
1107 	sensor->update = update;
1108 	sensor->convert = convert;
1109 	pmbus_dev_attr_init(a, sensor->name,
1110 			    readonly ? S_IRUGO : S_IRUGO | S_IWUSR,
1111 			    pmbus_show_sensor, pmbus_set_sensor);
1112 
1113 	if (pmbus_add_attribute(data, &a->attr))
1114 		return NULL;
1115 
1116 	sensor->next = data->sensors;
1117 	data->sensors = sensor;
1118 
1119 	return sensor;
1120 }
1121 
1122 static int pmbus_add_label(struct pmbus_data *data,
1123 			   const char *name, int seq,
1124 			   const char *lstring, int index)
1125 {
1126 	struct pmbus_label *label;
1127 	struct device_attribute *a;
1128 
1129 	label = devm_kzalloc(data->dev, sizeof(*label), GFP_KERNEL);
1130 	if (!label)
1131 		return -ENOMEM;
1132 
1133 	a = &label->attribute;
1134 
1135 	snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
1136 	if (!index)
1137 		strncpy(label->label, lstring, sizeof(label->label) - 1);
1138 	else
1139 		snprintf(label->label, sizeof(label->label), "%s%d", lstring,
1140 			 index);
1141 
1142 	pmbus_dev_attr_init(a, label->name, S_IRUGO, pmbus_show_label, NULL);
1143 	return pmbus_add_attribute(data, &a->attr);
1144 }
1145 
1146 /*
1147  * Search for attributes. Allocate sensors, booleans, and labels as needed.
1148  */
1149 
1150 /*
1151  * The pmbus_limit_attr structure describes a single limit attribute
1152  * and its associated alarm attribute.
1153  */
1154 struct pmbus_limit_attr {
1155 	u16 reg;		/* Limit register */
1156 	u16 sbit;		/* Alarm attribute status bit */
1157 	bool update;		/* True if register needs updates */
1158 	bool low;		/* True if low limit; for limits with compare
1159 				   functions only */
1160 	const char *attr;	/* Attribute name */
1161 	const char *alarm;	/* Alarm attribute name */
1162 };
1163 
1164 /*
1165  * The pmbus_sensor_attr structure describes one sensor attribute. This
1166  * description includes a reference to the associated limit attributes.
1167  */
1168 struct pmbus_sensor_attr {
1169 	u16 reg;			/* sensor register */
1170 	u16 gbit;			/* generic status bit */
1171 	u8 nlimit;			/* # of limit registers */
1172 	enum pmbus_sensor_classes class;/* sensor class */
1173 	const char *label;		/* sensor label */
1174 	bool paged;			/* true if paged sensor */
1175 	bool update;			/* true if update needed */
1176 	bool compare;			/* true if compare function needed */
1177 	u32 func;			/* sensor mask */
1178 	u32 sfunc;			/* sensor status mask */
1179 	int sbase;			/* status base register */
1180 	const struct pmbus_limit_attr *limit;/* limit registers */
1181 };
1182 
1183 /*
1184  * Add a set of limit attributes and, if supported, the associated
1185  * alarm attributes.
1186  * returns 0 if no alarm register found, 1 if an alarm register was found,
1187  * < 0 on errors.
1188  */
1189 static int pmbus_add_limit_attrs(struct i2c_client *client,
1190 				 struct pmbus_data *data,
1191 				 const struct pmbus_driver_info *info,
1192 				 const char *name, int index, int page,
1193 				 struct pmbus_sensor *base,
1194 				 const struct pmbus_sensor_attr *attr)
1195 {
1196 	const struct pmbus_limit_attr *l = attr->limit;
1197 	int nlimit = attr->nlimit;
1198 	int have_alarm = 0;
1199 	int i, ret;
1200 	struct pmbus_sensor *curr;
1201 
1202 	for (i = 0; i < nlimit; i++) {
1203 		if (pmbus_check_word_register(client, page, l->reg)) {
1204 			curr = pmbus_add_sensor(data, name, l->attr, index,
1205 						page, l->reg, attr->class,
1206 						attr->update || l->update,
1207 						false, true);
1208 			if (!curr)
1209 				return -ENOMEM;
1210 			if (l->sbit && (info->func[page] & attr->sfunc)) {
1211 				ret = pmbus_add_boolean(data, name,
1212 					l->alarm, index,
1213 					attr->compare ?  l->low ? curr : base
1214 						      : NULL,
1215 					attr->compare ? l->low ? base : curr
1216 						      : NULL,
1217 					attr->sbase + page, l->sbit);
1218 				if (ret)
1219 					return ret;
1220 				have_alarm = 1;
1221 			}
1222 		}
1223 		l++;
1224 	}
1225 	return have_alarm;
1226 }
1227 
1228 static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
1229 				      struct pmbus_data *data,
1230 				      const struct pmbus_driver_info *info,
1231 				      const char *name,
1232 				      int index, int page,
1233 				      const struct pmbus_sensor_attr *attr)
1234 {
1235 	struct pmbus_sensor *base;
1236 	bool upper = !!(attr->gbit & 0xff00);	/* need to check STATUS_WORD */
1237 	int ret;
1238 
1239 	if (attr->label) {
1240 		ret = pmbus_add_label(data, name, index, attr->label,
1241 				      attr->paged ? page + 1 : 0);
1242 		if (ret)
1243 			return ret;
1244 	}
1245 	base = pmbus_add_sensor(data, name, "input", index, page, attr->reg,
1246 				attr->class, true, true, true);
1247 	if (!base)
1248 		return -ENOMEM;
1249 	if (attr->sfunc) {
1250 		ret = pmbus_add_limit_attrs(client, data, info, name,
1251 					    index, page, base, attr);
1252 		if (ret < 0)
1253 			return ret;
1254 		/*
1255 		 * Add generic alarm attribute only if there are no individual
1256 		 * alarm attributes, if there is a global alarm bit, and if
1257 		 * the generic status register (word or byte, depending on
1258 		 * which global bit is set) for this page is accessible.
1259 		 */
1260 		if (!ret && attr->gbit &&
1261 		    (!upper || (upper && data->has_status_word)) &&
1262 		    pmbus_check_status_register(client, page)) {
1263 			ret = pmbus_add_boolean(data, name, "alarm", index,
1264 						NULL, NULL,
1265 						PB_STATUS_BASE + page,
1266 						attr->gbit);
1267 			if (ret)
1268 				return ret;
1269 		}
1270 	}
1271 	return 0;
1272 }
1273 
1274 static int pmbus_add_sensor_attrs(struct i2c_client *client,
1275 				  struct pmbus_data *data,
1276 				  const char *name,
1277 				  const struct pmbus_sensor_attr *attrs,
1278 				  int nattrs)
1279 {
1280 	const struct pmbus_driver_info *info = data->info;
1281 	int index, i;
1282 	int ret;
1283 
1284 	index = 1;
1285 	for (i = 0; i < nattrs; i++) {
1286 		int page, pages;
1287 
1288 		pages = attrs->paged ? info->pages : 1;
1289 		for (page = 0; page < pages; page++) {
1290 			if (!(info->func[page] & attrs->func))
1291 				continue;
1292 			ret = pmbus_add_sensor_attrs_one(client, data, info,
1293 							 name, index, page,
1294 							 attrs);
1295 			if (ret)
1296 				return ret;
1297 			index++;
1298 		}
1299 		attrs++;
1300 	}
1301 	return 0;
1302 }
1303 
1304 static const struct pmbus_limit_attr vin_limit_attrs[] = {
1305 	{
1306 		.reg = PMBUS_VIN_UV_WARN_LIMIT,
1307 		.attr = "min",
1308 		.alarm = "min_alarm",
1309 		.sbit = PB_VOLTAGE_UV_WARNING,
1310 	}, {
1311 		.reg = PMBUS_VIN_UV_FAULT_LIMIT,
1312 		.attr = "lcrit",
1313 		.alarm = "lcrit_alarm",
1314 		.sbit = PB_VOLTAGE_UV_FAULT,
1315 	}, {
1316 		.reg = PMBUS_VIN_OV_WARN_LIMIT,
1317 		.attr = "max",
1318 		.alarm = "max_alarm",
1319 		.sbit = PB_VOLTAGE_OV_WARNING,
1320 	}, {
1321 		.reg = PMBUS_VIN_OV_FAULT_LIMIT,
1322 		.attr = "crit",
1323 		.alarm = "crit_alarm",
1324 		.sbit = PB_VOLTAGE_OV_FAULT,
1325 	}, {
1326 		.reg = PMBUS_VIRT_READ_VIN_AVG,
1327 		.update = true,
1328 		.attr = "average",
1329 	}, {
1330 		.reg = PMBUS_VIRT_READ_VIN_MIN,
1331 		.update = true,
1332 		.attr = "lowest",
1333 	}, {
1334 		.reg = PMBUS_VIRT_READ_VIN_MAX,
1335 		.update = true,
1336 		.attr = "highest",
1337 	}, {
1338 		.reg = PMBUS_VIRT_RESET_VIN_HISTORY,
1339 		.attr = "reset_history",
1340 	},
1341 };
1342 
1343 static const struct pmbus_limit_attr vmon_limit_attrs[] = {
1344 	{
1345 		.reg = PMBUS_VIRT_VMON_UV_WARN_LIMIT,
1346 		.attr = "min",
1347 		.alarm = "min_alarm",
1348 		.sbit = PB_VOLTAGE_UV_WARNING,
1349 	}, {
1350 		.reg = PMBUS_VIRT_VMON_UV_FAULT_LIMIT,
1351 		.attr = "lcrit",
1352 		.alarm = "lcrit_alarm",
1353 		.sbit = PB_VOLTAGE_UV_FAULT,
1354 	}, {
1355 		.reg = PMBUS_VIRT_VMON_OV_WARN_LIMIT,
1356 		.attr = "max",
1357 		.alarm = "max_alarm",
1358 		.sbit = PB_VOLTAGE_OV_WARNING,
1359 	}, {
1360 		.reg = PMBUS_VIRT_VMON_OV_FAULT_LIMIT,
1361 		.attr = "crit",
1362 		.alarm = "crit_alarm",
1363 		.sbit = PB_VOLTAGE_OV_FAULT,
1364 	}
1365 };
1366 
1367 static const struct pmbus_limit_attr vout_limit_attrs[] = {
1368 	{
1369 		.reg = PMBUS_VOUT_UV_WARN_LIMIT,
1370 		.attr = "min",
1371 		.alarm = "min_alarm",
1372 		.sbit = PB_VOLTAGE_UV_WARNING,
1373 	}, {
1374 		.reg = PMBUS_VOUT_UV_FAULT_LIMIT,
1375 		.attr = "lcrit",
1376 		.alarm = "lcrit_alarm",
1377 		.sbit = PB_VOLTAGE_UV_FAULT,
1378 	}, {
1379 		.reg = PMBUS_VOUT_OV_WARN_LIMIT,
1380 		.attr = "max",
1381 		.alarm = "max_alarm",
1382 		.sbit = PB_VOLTAGE_OV_WARNING,
1383 	}, {
1384 		.reg = PMBUS_VOUT_OV_FAULT_LIMIT,
1385 		.attr = "crit",
1386 		.alarm = "crit_alarm",
1387 		.sbit = PB_VOLTAGE_OV_FAULT,
1388 	}, {
1389 		.reg = PMBUS_VIRT_READ_VOUT_AVG,
1390 		.update = true,
1391 		.attr = "average",
1392 	}, {
1393 		.reg = PMBUS_VIRT_READ_VOUT_MIN,
1394 		.update = true,
1395 		.attr = "lowest",
1396 	}, {
1397 		.reg = PMBUS_VIRT_READ_VOUT_MAX,
1398 		.update = true,
1399 		.attr = "highest",
1400 	}, {
1401 		.reg = PMBUS_VIRT_RESET_VOUT_HISTORY,
1402 		.attr = "reset_history",
1403 	}
1404 };
1405 
1406 static const struct pmbus_sensor_attr voltage_attributes[] = {
1407 	{
1408 		.reg = PMBUS_READ_VIN,
1409 		.class = PSC_VOLTAGE_IN,
1410 		.label = "vin",
1411 		.func = PMBUS_HAVE_VIN,
1412 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1413 		.sbase = PB_STATUS_INPUT_BASE,
1414 		.gbit = PB_STATUS_VIN_UV,
1415 		.limit = vin_limit_attrs,
1416 		.nlimit = ARRAY_SIZE(vin_limit_attrs),
1417 	}, {
1418 		.reg = PMBUS_VIRT_READ_VMON,
1419 		.class = PSC_VOLTAGE_IN,
1420 		.label = "vmon",
1421 		.func = PMBUS_HAVE_VMON,
1422 		.sfunc = PMBUS_HAVE_STATUS_VMON,
1423 		.sbase = PB_STATUS_VMON_BASE,
1424 		.limit = vmon_limit_attrs,
1425 		.nlimit = ARRAY_SIZE(vmon_limit_attrs),
1426 	}, {
1427 		.reg = PMBUS_READ_VCAP,
1428 		.class = PSC_VOLTAGE_IN,
1429 		.label = "vcap",
1430 		.func = PMBUS_HAVE_VCAP,
1431 	}, {
1432 		.reg = PMBUS_READ_VOUT,
1433 		.class = PSC_VOLTAGE_OUT,
1434 		.label = "vout",
1435 		.paged = true,
1436 		.func = PMBUS_HAVE_VOUT,
1437 		.sfunc = PMBUS_HAVE_STATUS_VOUT,
1438 		.sbase = PB_STATUS_VOUT_BASE,
1439 		.gbit = PB_STATUS_VOUT_OV,
1440 		.limit = vout_limit_attrs,
1441 		.nlimit = ARRAY_SIZE(vout_limit_attrs),
1442 	}
1443 };
1444 
1445 /* Current attributes */
1446 
1447 static const struct pmbus_limit_attr iin_limit_attrs[] = {
1448 	{
1449 		.reg = PMBUS_IIN_OC_WARN_LIMIT,
1450 		.attr = "max",
1451 		.alarm = "max_alarm",
1452 		.sbit = PB_IIN_OC_WARNING,
1453 	}, {
1454 		.reg = PMBUS_IIN_OC_FAULT_LIMIT,
1455 		.attr = "crit",
1456 		.alarm = "crit_alarm",
1457 		.sbit = PB_IIN_OC_FAULT,
1458 	}, {
1459 		.reg = PMBUS_VIRT_READ_IIN_AVG,
1460 		.update = true,
1461 		.attr = "average",
1462 	}, {
1463 		.reg = PMBUS_VIRT_READ_IIN_MIN,
1464 		.update = true,
1465 		.attr = "lowest",
1466 	}, {
1467 		.reg = PMBUS_VIRT_READ_IIN_MAX,
1468 		.update = true,
1469 		.attr = "highest",
1470 	}, {
1471 		.reg = PMBUS_VIRT_RESET_IIN_HISTORY,
1472 		.attr = "reset_history",
1473 	}
1474 };
1475 
1476 static const struct pmbus_limit_attr iout_limit_attrs[] = {
1477 	{
1478 		.reg = PMBUS_IOUT_OC_WARN_LIMIT,
1479 		.attr = "max",
1480 		.alarm = "max_alarm",
1481 		.sbit = PB_IOUT_OC_WARNING,
1482 	}, {
1483 		.reg = PMBUS_IOUT_UC_FAULT_LIMIT,
1484 		.attr = "lcrit",
1485 		.alarm = "lcrit_alarm",
1486 		.sbit = PB_IOUT_UC_FAULT,
1487 	}, {
1488 		.reg = PMBUS_IOUT_OC_FAULT_LIMIT,
1489 		.attr = "crit",
1490 		.alarm = "crit_alarm",
1491 		.sbit = PB_IOUT_OC_FAULT,
1492 	}, {
1493 		.reg = PMBUS_VIRT_READ_IOUT_AVG,
1494 		.update = true,
1495 		.attr = "average",
1496 	}, {
1497 		.reg = PMBUS_VIRT_READ_IOUT_MIN,
1498 		.update = true,
1499 		.attr = "lowest",
1500 	}, {
1501 		.reg = PMBUS_VIRT_READ_IOUT_MAX,
1502 		.update = true,
1503 		.attr = "highest",
1504 	}, {
1505 		.reg = PMBUS_VIRT_RESET_IOUT_HISTORY,
1506 		.attr = "reset_history",
1507 	}
1508 };
1509 
1510 static const struct pmbus_sensor_attr current_attributes[] = {
1511 	{
1512 		.reg = PMBUS_READ_IIN,
1513 		.class = PSC_CURRENT_IN,
1514 		.label = "iin",
1515 		.func = PMBUS_HAVE_IIN,
1516 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1517 		.sbase = PB_STATUS_INPUT_BASE,
1518 		.gbit = PB_STATUS_INPUT,
1519 		.limit = iin_limit_attrs,
1520 		.nlimit = ARRAY_SIZE(iin_limit_attrs),
1521 	}, {
1522 		.reg = PMBUS_READ_IOUT,
1523 		.class = PSC_CURRENT_OUT,
1524 		.label = "iout",
1525 		.paged = true,
1526 		.func = PMBUS_HAVE_IOUT,
1527 		.sfunc = PMBUS_HAVE_STATUS_IOUT,
1528 		.sbase = PB_STATUS_IOUT_BASE,
1529 		.gbit = PB_STATUS_IOUT_OC,
1530 		.limit = iout_limit_attrs,
1531 		.nlimit = ARRAY_SIZE(iout_limit_attrs),
1532 	}
1533 };
1534 
1535 /* Power attributes */
1536 
1537 static const struct pmbus_limit_attr pin_limit_attrs[] = {
1538 	{
1539 		.reg = PMBUS_PIN_OP_WARN_LIMIT,
1540 		.attr = "max",
1541 		.alarm = "alarm",
1542 		.sbit = PB_PIN_OP_WARNING,
1543 	}, {
1544 		.reg = PMBUS_VIRT_READ_PIN_AVG,
1545 		.update = true,
1546 		.attr = "average",
1547 	}, {
1548 		.reg = PMBUS_VIRT_READ_PIN_MIN,
1549 		.update = true,
1550 		.attr = "input_lowest",
1551 	}, {
1552 		.reg = PMBUS_VIRT_READ_PIN_MAX,
1553 		.update = true,
1554 		.attr = "input_highest",
1555 	}, {
1556 		.reg = PMBUS_VIRT_RESET_PIN_HISTORY,
1557 		.attr = "reset_history",
1558 	}
1559 };
1560 
1561 static const struct pmbus_limit_attr pout_limit_attrs[] = {
1562 	{
1563 		.reg = PMBUS_POUT_MAX,
1564 		.attr = "cap",
1565 		.alarm = "cap_alarm",
1566 		.sbit = PB_POWER_LIMITING,
1567 	}, {
1568 		.reg = PMBUS_POUT_OP_WARN_LIMIT,
1569 		.attr = "max",
1570 		.alarm = "max_alarm",
1571 		.sbit = PB_POUT_OP_WARNING,
1572 	}, {
1573 		.reg = PMBUS_POUT_OP_FAULT_LIMIT,
1574 		.attr = "crit",
1575 		.alarm = "crit_alarm",
1576 		.sbit = PB_POUT_OP_FAULT,
1577 	}, {
1578 		.reg = PMBUS_VIRT_READ_POUT_AVG,
1579 		.update = true,
1580 		.attr = "average",
1581 	}, {
1582 		.reg = PMBUS_VIRT_READ_POUT_MIN,
1583 		.update = true,
1584 		.attr = "input_lowest",
1585 	}, {
1586 		.reg = PMBUS_VIRT_READ_POUT_MAX,
1587 		.update = true,
1588 		.attr = "input_highest",
1589 	}, {
1590 		.reg = PMBUS_VIRT_RESET_POUT_HISTORY,
1591 		.attr = "reset_history",
1592 	}
1593 };
1594 
1595 static const struct pmbus_sensor_attr power_attributes[] = {
1596 	{
1597 		.reg = PMBUS_READ_PIN,
1598 		.class = PSC_POWER,
1599 		.label = "pin",
1600 		.func = PMBUS_HAVE_PIN,
1601 		.sfunc = PMBUS_HAVE_STATUS_INPUT,
1602 		.sbase = PB_STATUS_INPUT_BASE,
1603 		.gbit = PB_STATUS_INPUT,
1604 		.limit = pin_limit_attrs,
1605 		.nlimit = ARRAY_SIZE(pin_limit_attrs),
1606 	}, {
1607 		.reg = PMBUS_READ_POUT,
1608 		.class = PSC_POWER,
1609 		.label = "pout",
1610 		.paged = true,
1611 		.func = PMBUS_HAVE_POUT,
1612 		.sfunc = PMBUS_HAVE_STATUS_IOUT,
1613 		.sbase = PB_STATUS_IOUT_BASE,
1614 		.limit = pout_limit_attrs,
1615 		.nlimit = ARRAY_SIZE(pout_limit_attrs),
1616 	}
1617 };
1618 
1619 /* Temperature atributes */
1620 
1621 static const struct pmbus_limit_attr temp_limit_attrs[] = {
1622 	{
1623 		.reg = PMBUS_UT_WARN_LIMIT,
1624 		.low = true,
1625 		.attr = "min",
1626 		.alarm = "min_alarm",
1627 		.sbit = PB_TEMP_UT_WARNING,
1628 	}, {
1629 		.reg = PMBUS_UT_FAULT_LIMIT,
1630 		.low = true,
1631 		.attr = "lcrit",
1632 		.alarm = "lcrit_alarm",
1633 		.sbit = PB_TEMP_UT_FAULT,
1634 	}, {
1635 		.reg = PMBUS_OT_WARN_LIMIT,
1636 		.attr = "max",
1637 		.alarm = "max_alarm",
1638 		.sbit = PB_TEMP_OT_WARNING,
1639 	}, {
1640 		.reg = PMBUS_OT_FAULT_LIMIT,
1641 		.attr = "crit",
1642 		.alarm = "crit_alarm",
1643 		.sbit = PB_TEMP_OT_FAULT,
1644 	}, {
1645 		.reg = PMBUS_VIRT_READ_TEMP_MIN,
1646 		.attr = "lowest",
1647 	}, {
1648 		.reg = PMBUS_VIRT_READ_TEMP_AVG,
1649 		.attr = "average",
1650 	}, {
1651 		.reg = PMBUS_VIRT_READ_TEMP_MAX,
1652 		.attr = "highest",
1653 	}, {
1654 		.reg = PMBUS_VIRT_RESET_TEMP_HISTORY,
1655 		.attr = "reset_history",
1656 	}
1657 };
1658 
1659 static const struct pmbus_limit_attr temp_limit_attrs2[] = {
1660 	{
1661 		.reg = PMBUS_UT_WARN_LIMIT,
1662 		.low = true,
1663 		.attr = "min",
1664 		.alarm = "min_alarm",
1665 		.sbit = PB_TEMP_UT_WARNING,
1666 	}, {
1667 		.reg = PMBUS_UT_FAULT_LIMIT,
1668 		.low = true,
1669 		.attr = "lcrit",
1670 		.alarm = "lcrit_alarm",
1671 		.sbit = PB_TEMP_UT_FAULT,
1672 	}, {
1673 		.reg = PMBUS_OT_WARN_LIMIT,
1674 		.attr = "max",
1675 		.alarm = "max_alarm",
1676 		.sbit = PB_TEMP_OT_WARNING,
1677 	}, {
1678 		.reg = PMBUS_OT_FAULT_LIMIT,
1679 		.attr = "crit",
1680 		.alarm = "crit_alarm",
1681 		.sbit = PB_TEMP_OT_FAULT,
1682 	}, {
1683 		.reg = PMBUS_VIRT_READ_TEMP2_MIN,
1684 		.attr = "lowest",
1685 	}, {
1686 		.reg = PMBUS_VIRT_READ_TEMP2_AVG,
1687 		.attr = "average",
1688 	}, {
1689 		.reg = PMBUS_VIRT_READ_TEMP2_MAX,
1690 		.attr = "highest",
1691 	}, {
1692 		.reg = PMBUS_VIRT_RESET_TEMP2_HISTORY,
1693 		.attr = "reset_history",
1694 	}
1695 };
1696 
1697 static const struct pmbus_limit_attr temp_limit_attrs3[] = {
1698 	{
1699 		.reg = PMBUS_UT_WARN_LIMIT,
1700 		.low = true,
1701 		.attr = "min",
1702 		.alarm = "min_alarm",
1703 		.sbit = PB_TEMP_UT_WARNING,
1704 	}, {
1705 		.reg = PMBUS_UT_FAULT_LIMIT,
1706 		.low = true,
1707 		.attr = "lcrit",
1708 		.alarm = "lcrit_alarm",
1709 		.sbit = PB_TEMP_UT_FAULT,
1710 	}, {
1711 		.reg = PMBUS_OT_WARN_LIMIT,
1712 		.attr = "max",
1713 		.alarm = "max_alarm",
1714 		.sbit = PB_TEMP_OT_WARNING,
1715 	}, {
1716 		.reg = PMBUS_OT_FAULT_LIMIT,
1717 		.attr = "crit",
1718 		.alarm = "crit_alarm",
1719 		.sbit = PB_TEMP_OT_FAULT,
1720 	}
1721 };
1722 
1723 static const struct pmbus_sensor_attr temp_attributes[] = {
1724 	{
1725 		.reg = PMBUS_READ_TEMPERATURE_1,
1726 		.class = PSC_TEMPERATURE,
1727 		.paged = true,
1728 		.update = true,
1729 		.compare = true,
1730 		.func = PMBUS_HAVE_TEMP,
1731 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1732 		.sbase = PB_STATUS_TEMP_BASE,
1733 		.gbit = PB_STATUS_TEMPERATURE,
1734 		.limit = temp_limit_attrs,
1735 		.nlimit = ARRAY_SIZE(temp_limit_attrs),
1736 	}, {
1737 		.reg = PMBUS_READ_TEMPERATURE_2,
1738 		.class = PSC_TEMPERATURE,
1739 		.paged = true,
1740 		.update = true,
1741 		.compare = true,
1742 		.func = PMBUS_HAVE_TEMP2,
1743 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1744 		.sbase = PB_STATUS_TEMP_BASE,
1745 		.gbit = PB_STATUS_TEMPERATURE,
1746 		.limit = temp_limit_attrs2,
1747 		.nlimit = ARRAY_SIZE(temp_limit_attrs2),
1748 	}, {
1749 		.reg = PMBUS_READ_TEMPERATURE_3,
1750 		.class = PSC_TEMPERATURE,
1751 		.paged = true,
1752 		.update = true,
1753 		.compare = true,
1754 		.func = PMBUS_HAVE_TEMP3,
1755 		.sfunc = PMBUS_HAVE_STATUS_TEMP,
1756 		.sbase = PB_STATUS_TEMP_BASE,
1757 		.gbit = PB_STATUS_TEMPERATURE,
1758 		.limit = temp_limit_attrs3,
1759 		.nlimit = ARRAY_SIZE(temp_limit_attrs3),
1760 	}
1761 };
1762 
1763 static const int pmbus_fan_registers[] = {
1764 	PMBUS_READ_FAN_SPEED_1,
1765 	PMBUS_READ_FAN_SPEED_2,
1766 	PMBUS_READ_FAN_SPEED_3,
1767 	PMBUS_READ_FAN_SPEED_4
1768 };
1769 
1770 static const int pmbus_fan_status_registers[] = {
1771 	PMBUS_STATUS_FAN_12,
1772 	PMBUS_STATUS_FAN_12,
1773 	PMBUS_STATUS_FAN_34,
1774 	PMBUS_STATUS_FAN_34
1775 };
1776 
1777 static const u32 pmbus_fan_flags[] = {
1778 	PMBUS_HAVE_FAN12,
1779 	PMBUS_HAVE_FAN12,
1780 	PMBUS_HAVE_FAN34,
1781 	PMBUS_HAVE_FAN34
1782 };
1783 
1784 static const u32 pmbus_fan_status_flags[] = {
1785 	PMBUS_HAVE_STATUS_FAN12,
1786 	PMBUS_HAVE_STATUS_FAN12,
1787 	PMBUS_HAVE_STATUS_FAN34,
1788 	PMBUS_HAVE_STATUS_FAN34
1789 };
1790 
1791 /* Fans */
1792 
1793 /* Precondition: FAN_CONFIG_x_y and FAN_COMMAND_x must exist for the fan ID */
1794 static int pmbus_add_fan_ctrl(struct i2c_client *client,
1795 		struct pmbus_data *data, int index, int page, int id,
1796 		u8 config)
1797 {
1798 	struct pmbus_sensor *sensor;
1799 
1800 	sensor = pmbus_add_sensor(data, "fan", "target", index, page,
1801 				  PMBUS_VIRT_FAN_TARGET_1 + id, PSC_FAN,
1802 				  false, false, true);
1803 
1804 	if (!sensor)
1805 		return -ENOMEM;
1806 
1807 	if (!((data->info->func[page] & PMBUS_HAVE_PWM12) ||
1808 			(data->info->func[page] & PMBUS_HAVE_PWM34)))
1809 		return 0;
1810 
1811 	sensor = pmbus_add_sensor(data, "pwm", NULL, index, page,
1812 				  PMBUS_VIRT_PWM_1 + id, PSC_PWM,
1813 				  false, false, true);
1814 
1815 	if (!sensor)
1816 		return -ENOMEM;
1817 
1818 	sensor = pmbus_add_sensor(data, "pwm", "enable", index, page,
1819 				  PMBUS_VIRT_PWM_ENABLE_1 + id, PSC_PWM,
1820 				  true, false, false);
1821 
1822 	if (!sensor)
1823 		return -ENOMEM;
1824 
1825 	return 0;
1826 }
1827 
1828 static int pmbus_add_fan_attributes(struct i2c_client *client,
1829 				    struct pmbus_data *data)
1830 {
1831 	const struct pmbus_driver_info *info = data->info;
1832 	int index = 1;
1833 	int page;
1834 	int ret;
1835 
1836 	for (page = 0; page < info->pages; page++) {
1837 		int f;
1838 
1839 		for (f = 0; f < ARRAY_SIZE(pmbus_fan_registers); f++) {
1840 			int regval;
1841 
1842 			if (!(info->func[page] & pmbus_fan_flags[f]))
1843 				break;
1844 
1845 			if (!pmbus_check_word_register(client, page,
1846 						       pmbus_fan_registers[f]))
1847 				break;
1848 
1849 			/*
1850 			 * Skip fan if not installed.
1851 			 * Each fan configuration register covers multiple fans,
1852 			 * so we have to do some magic.
1853 			 */
1854 			regval = _pmbus_read_byte_data(client, page,
1855 				pmbus_fan_config_registers[f]);
1856 			if (regval < 0 ||
1857 			    (!(regval & (PB_FAN_1_INSTALLED >> ((f & 1) * 4)))))
1858 				continue;
1859 
1860 			if (pmbus_add_sensor(data, "fan", "input", index,
1861 					     page, pmbus_fan_registers[f],
1862 					     PSC_FAN, true, true, true) == NULL)
1863 				return -ENOMEM;
1864 
1865 			/* Fan control */
1866 			if (pmbus_check_word_register(client, page,
1867 					pmbus_fan_command_registers[f])) {
1868 				ret = pmbus_add_fan_ctrl(client, data, index,
1869 							 page, f, regval);
1870 				if (ret < 0)
1871 					return ret;
1872 			}
1873 
1874 			/*
1875 			 * Each fan status register covers multiple fans,
1876 			 * so we have to do some magic.
1877 			 */
1878 			if ((info->func[page] & pmbus_fan_status_flags[f]) &&
1879 			    pmbus_check_byte_register(client,
1880 					page, pmbus_fan_status_registers[f])) {
1881 				int base;
1882 
1883 				if (f > 1)	/* fan 3, 4 */
1884 					base = PB_STATUS_FAN34_BASE + page;
1885 				else
1886 					base = PB_STATUS_FAN_BASE + page;
1887 				ret = pmbus_add_boolean(data, "fan",
1888 					"alarm", index, NULL, NULL, base,
1889 					PB_FAN_FAN1_WARNING >> (f & 1));
1890 				if (ret)
1891 					return ret;
1892 				ret = pmbus_add_boolean(data, "fan",
1893 					"fault", index, NULL, NULL, base,
1894 					PB_FAN_FAN1_FAULT >> (f & 1));
1895 				if (ret)
1896 					return ret;
1897 			}
1898 			index++;
1899 		}
1900 	}
1901 	return 0;
1902 }
1903 
1904 static int pmbus_find_attributes(struct i2c_client *client,
1905 				 struct pmbus_data *data)
1906 {
1907 	int ret;
1908 
1909 	/* Voltage sensors */
1910 	ret = pmbus_add_sensor_attrs(client, data, "in", voltage_attributes,
1911 				     ARRAY_SIZE(voltage_attributes));
1912 	if (ret)
1913 		return ret;
1914 
1915 	/* Current sensors */
1916 	ret = pmbus_add_sensor_attrs(client, data, "curr", current_attributes,
1917 				     ARRAY_SIZE(current_attributes));
1918 	if (ret)
1919 		return ret;
1920 
1921 	/* Power sensors */
1922 	ret = pmbus_add_sensor_attrs(client, data, "power", power_attributes,
1923 				     ARRAY_SIZE(power_attributes));
1924 	if (ret)
1925 		return ret;
1926 
1927 	/* Temperature sensors */
1928 	ret = pmbus_add_sensor_attrs(client, data, "temp", temp_attributes,
1929 				     ARRAY_SIZE(temp_attributes));
1930 	if (ret)
1931 		return ret;
1932 
1933 	/* Fans */
1934 	ret = pmbus_add_fan_attributes(client, data);
1935 	return ret;
1936 }
1937 
1938 /*
1939  * Identify chip parameters.
1940  * This function is called for all chips.
1941  */
1942 static int pmbus_identify_common(struct i2c_client *client,
1943 				 struct pmbus_data *data, int page)
1944 {
1945 	int vout_mode = -1;
1946 
1947 	if (pmbus_check_byte_register(client, page, PMBUS_VOUT_MODE))
1948 		vout_mode = _pmbus_read_byte_data(client, page,
1949 						  PMBUS_VOUT_MODE);
1950 	if (vout_mode >= 0 && vout_mode != 0xff) {
1951 		/*
1952 		 * Not all chips support the VOUT_MODE command,
1953 		 * so a failure to read it is not an error.
1954 		 */
1955 		switch (vout_mode >> 5) {
1956 		case 0:	/* linear mode      */
1957 			if (data->info->format[PSC_VOLTAGE_OUT] != linear)
1958 				return -ENODEV;
1959 
1960 			data->exponent[page] = ((s8)(vout_mode << 3)) >> 3;
1961 			break;
1962 		case 1: /* VID mode         */
1963 			if (data->info->format[PSC_VOLTAGE_OUT] != vid)
1964 				return -ENODEV;
1965 			break;
1966 		case 2:	/* direct mode      */
1967 			if (data->info->format[PSC_VOLTAGE_OUT] != direct)
1968 				return -ENODEV;
1969 			break;
1970 		default:
1971 			return -ENODEV;
1972 		}
1973 	}
1974 
1975 	pmbus_clear_fault_page(client, page);
1976 	return 0;
1977 }
1978 
1979 static int pmbus_read_status_byte(struct i2c_client *client, int page)
1980 {
1981 	return _pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE);
1982 }
1983 
1984 static int pmbus_read_status_word(struct i2c_client *client, int page)
1985 {
1986 	return _pmbus_read_word_data(client, page, PMBUS_STATUS_WORD);
1987 }
1988 
1989 static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data,
1990 			     struct pmbus_driver_info *info)
1991 {
1992 	struct device *dev = &client->dev;
1993 	int page, ret;
1994 
1995 	/*
1996 	 * Some PMBus chips don't support PMBUS_STATUS_WORD, so try
1997 	 * to use PMBUS_STATUS_BYTE instead if that is the case.
1998 	 * Bail out if both registers are not supported.
1999 	 */
2000 	data->read_status = pmbus_read_status_word;
2001 	ret = i2c_smbus_read_word_data(client, PMBUS_STATUS_WORD);
2002 	if (ret < 0 || ret == 0xffff) {
2003 		data->read_status = pmbus_read_status_byte;
2004 		ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE);
2005 		if (ret < 0 || ret == 0xff) {
2006 			dev_err(dev, "PMBus status register not found\n");
2007 			return -ENODEV;
2008 		}
2009 	} else {
2010 		data->has_status_word = true;
2011 	}
2012 
2013 	/* Enable PEC if the controller supports it */
2014 	ret = i2c_smbus_read_byte_data(client, PMBUS_CAPABILITY);
2015 	if (ret >= 0 && (ret & PB_CAPABILITY_ERROR_CHECK))
2016 		client->flags |= I2C_CLIENT_PEC;
2017 
2018 	pmbus_clear_faults(client);
2019 
2020 	if (info->identify) {
2021 		ret = (*info->identify)(client, info);
2022 		if (ret < 0) {
2023 			dev_err(dev, "Chip identification failed\n");
2024 			return ret;
2025 		}
2026 	}
2027 
2028 	if (info->pages <= 0 || info->pages > PMBUS_PAGES) {
2029 		dev_err(dev, "Bad number of PMBus pages: %d\n", info->pages);
2030 		return -ENODEV;
2031 	}
2032 
2033 	for (page = 0; page < info->pages; page++) {
2034 		ret = pmbus_identify_common(client, data, page);
2035 		if (ret < 0) {
2036 			dev_err(dev, "Failed to identify chip capabilities\n");
2037 			return ret;
2038 		}
2039 	}
2040 	return 0;
2041 }
2042 
2043 #if IS_ENABLED(CONFIG_REGULATOR)
2044 static int pmbus_regulator_is_enabled(struct regulator_dev *rdev)
2045 {
2046 	struct device *dev = rdev_get_dev(rdev);
2047 	struct i2c_client *client = to_i2c_client(dev->parent);
2048 	u8 page = rdev_get_id(rdev);
2049 	int ret;
2050 
2051 	ret = pmbus_read_byte_data(client, page, PMBUS_OPERATION);
2052 	if (ret < 0)
2053 		return ret;
2054 
2055 	return !!(ret & PB_OPERATION_CONTROL_ON);
2056 }
2057 
2058 static int _pmbus_regulator_on_off(struct regulator_dev *rdev, bool enable)
2059 {
2060 	struct device *dev = rdev_get_dev(rdev);
2061 	struct i2c_client *client = to_i2c_client(dev->parent);
2062 	u8 page = rdev_get_id(rdev);
2063 
2064 	return pmbus_update_byte_data(client, page, PMBUS_OPERATION,
2065 				      PB_OPERATION_CONTROL_ON,
2066 				      enable ? PB_OPERATION_CONTROL_ON : 0);
2067 }
2068 
2069 static int pmbus_regulator_enable(struct regulator_dev *rdev)
2070 {
2071 	return _pmbus_regulator_on_off(rdev, 1);
2072 }
2073 
2074 static int pmbus_regulator_disable(struct regulator_dev *rdev)
2075 {
2076 	return _pmbus_regulator_on_off(rdev, 0);
2077 }
2078 
2079 const struct regulator_ops pmbus_regulator_ops = {
2080 	.enable = pmbus_regulator_enable,
2081 	.disable = pmbus_regulator_disable,
2082 	.is_enabled = pmbus_regulator_is_enabled,
2083 };
2084 EXPORT_SYMBOL_GPL(pmbus_regulator_ops);
2085 
2086 static int pmbus_regulator_register(struct pmbus_data *data)
2087 {
2088 	struct device *dev = data->dev;
2089 	const struct pmbus_driver_info *info = data->info;
2090 	const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
2091 	struct regulator_dev *rdev;
2092 	int i;
2093 
2094 	for (i = 0; i < info->num_regulators; i++) {
2095 		struct regulator_config config = { };
2096 
2097 		config.dev = dev;
2098 		config.driver_data = data;
2099 
2100 		if (pdata && pdata->reg_init_data)
2101 			config.init_data = &pdata->reg_init_data[i];
2102 
2103 		rdev = devm_regulator_register(dev, &info->reg_desc[i],
2104 					       &config);
2105 		if (IS_ERR(rdev)) {
2106 			dev_err(dev, "Failed to register %s regulator\n",
2107 				info->reg_desc[i].name);
2108 			return PTR_ERR(rdev);
2109 		}
2110 	}
2111 
2112 	return 0;
2113 }
2114 #else
2115 static int pmbus_regulator_register(struct pmbus_data *data)
2116 {
2117 	return 0;
2118 }
2119 #endif
2120 
2121 static struct dentry *pmbus_debugfs_dir;	/* pmbus debugfs directory */
2122 
2123 #if IS_ENABLED(CONFIG_DEBUG_FS)
2124 static int pmbus_debugfs_get(void *data, u64 *val)
2125 {
2126 	int rc;
2127 	struct pmbus_debugfs_entry *entry = data;
2128 
2129 	rc = _pmbus_read_byte_data(entry->client, entry->page, entry->reg);
2130 	if (rc < 0)
2131 		return rc;
2132 
2133 	*val = rc;
2134 
2135 	return 0;
2136 }
2137 DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops, pmbus_debugfs_get, NULL,
2138 			 "0x%02llx\n");
2139 
2140 static int pmbus_debugfs_get_status(void *data, u64 *val)
2141 {
2142 	int rc;
2143 	struct pmbus_debugfs_entry *entry = data;
2144 	struct pmbus_data *pdata = i2c_get_clientdata(entry->client);
2145 
2146 	rc = pdata->read_status(entry->client, entry->page);
2147 	if (rc < 0)
2148 		return rc;
2149 
2150 	*val = rc;
2151 
2152 	return 0;
2153 }
2154 DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops_status, pmbus_debugfs_get_status,
2155 			 NULL, "0x%04llx\n");
2156 
2157 static int pmbus_init_debugfs(struct i2c_client *client,
2158 			      struct pmbus_data *data)
2159 {
2160 	int i, idx = 0;
2161 	char name[PMBUS_NAME_SIZE];
2162 	struct pmbus_debugfs_entry *entries;
2163 
2164 	if (!pmbus_debugfs_dir)
2165 		return -ENODEV;
2166 
2167 	/*
2168 	 * Create the debugfs directory for this device. Use the hwmon device
2169 	 * name to avoid conflicts (hwmon numbers are globally unique).
2170 	 */
2171 	data->debugfs = debugfs_create_dir(dev_name(data->hwmon_dev),
2172 					   pmbus_debugfs_dir);
2173 	if (IS_ERR_OR_NULL(data->debugfs)) {
2174 		data->debugfs = NULL;
2175 		return -ENODEV;
2176 	}
2177 
2178 	/* Allocate the max possible entries we need. */
2179 	entries = devm_kzalloc(data->dev,
2180 			       sizeof(*entries) * (data->info->pages * 10),
2181 			       GFP_KERNEL);
2182 	if (!entries)
2183 		return -ENOMEM;
2184 
2185 	for (i = 0; i < data->info->pages; ++i) {
2186 		/* Check accessibility of status register if it's not page 0 */
2187 		if (!i || pmbus_check_status_register(client, i)) {
2188 			/* No need to set reg as we have special read op. */
2189 			entries[idx].client = client;
2190 			entries[idx].page = i;
2191 			scnprintf(name, PMBUS_NAME_SIZE, "status%d", i);
2192 			debugfs_create_file(name, 0444, data->debugfs,
2193 					    &entries[idx++],
2194 					    &pmbus_debugfs_ops_status);
2195 		}
2196 
2197 		if (data->info->func[i] & PMBUS_HAVE_STATUS_VOUT) {
2198 			entries[idx].client = client;
2199 			entries[idx].page = i;
2200 			entries[idx].reg = PMBUS_STATUS_VOUT;
2201 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_vout", i);
2202 			debugfs_create_file(name, 0444, data->debugfs,
2203 					    &entries[idx++],
2204 					    &pmbus_debugfs_ops);
2205 		}
2206 
2207 		if (data->info->func[i] & PMBUS_HAVE_STATUS_IOUT) {
2208 			entries[idx].client = client;
2209 			entries[idx].page = i;
2210 			entries[idx].reg = PMBUS_STATUS_IOUT;
2211 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_iout", i);
2212 			debugfs_create_file(name, 0444, data->debugfs,
2213 					    &entries[idx++],
2214 					    &pmbus_debugfs_ops);
2215 		}
2216 
2217 		if (data->info->func[i] & PMBUS_HAVE_STATUS_INPUT) {
2218 			entries[idx].client = client;
2219 			entries[idx].page = i;
2220 			entries[idx].reg = PMBUS_STATUS_INPUT;
2221 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_input", i);
2222 			debugfs_create_file(name, 0444, data->debugfs,
2223 					    &entries[idx++],
2224 					    &pmbus_debugfs_ops);
2225 		}
2226 
2227 		if (data->info->func[i] & PMBUS_HAVE_STATUS_TEMP) {
2228 			entries[idx].client = client;
2229 			entries[idx].page = i;
2230 			entries[idx].reg = PMBUS_STATUS_TEMPERATURE;
2231 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_temp", i);
2232 			debugfs_create_file(name, 0444, data->debugfs,
2233 					    &entries[idx++],
2234 					    &pmbus_debugfs_ops);
2235 		}
2236 
2237 		if (pmbus_check_byte_register(client, i, PMBUS_STATUS_CML)) {
2238 			entries[idx].client = client;
2239 			entries[idx].page = i;
2240 			entries[idx].reg = PMBUS_STATUS_CML;
2241 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_cml", i);
2242 			debugfs_create_file(name, 0444, data->debugfs,
2243 					    &entries[idx++],
2244 					    &pmbus_debugfs_ops);
2245 		}
2246 
2247 		if (pmbus_check_byte_register(client, i, PMBUS_STATUS_OTHER)) {
2248 			entries[idx].client = client;
2249 			entries[idx].page = i;
2250 			entries[idx].reg = PMBUS_STATUS_OTHER;
2251 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_other", i);
2252 			debugfs_create_file(name, 0444, data->debugfs,
2253 					    &entries[idx++],
2254 					    &pmbus_debugfs_ops);
2255 		}
2256 
2257 		if (pmbus_check_byte_register(client, i,
2258 					      PMBUS_STATUS_MFR_SPECIFIC)) {
2259 			entries[idx].client = client;
2260 			entries[idx].page = i;
2261 			entries[idx].reg = PMBUS_STATUS_MFR_SPECIFIC;
2262 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_mfr", i);
2263 			debugfs_create_file(name, 0444, data->debugfs,
2264 					    &entries[idx++],
2265 					    &pmbus_debugfs_ops);
2266 		}
2267 
2268 		if (data->info->func[i] & PMBUS_HAVE_STATUS_FAN12) {
2269 			entries[idx].client = client;
2270 			entries[idx].page = i;
2271 			entries[idx].reg = PMBUS_STATUS_FAN_12;
2272 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_fan12", i);
2273 			debugfs_create_file(name, 0444, data->debugfs,
2274 					    &entries[idx++],
2275 					    &pmbus_debugfs_ops);
2276 		}
2277 
2278 		if (data->info->func[i] & PMBUS_HAVE_STATUS_FAN34) {
2279 			entries[idx].client = client;
2280 			entries[idx].page = i;
2281 			entries[idx].reg = PMBUS_STATUS_FAN_34;
2282 			scnprintf(name, PMBUS_NAME_SIZE, "status%d_fan34", i);
2283 			debugfs_create_file(name, 0444, data->debugfs,
2284 					    &entries[idx++],
2285 					    &pmbus_debugfs_ops);
2286 		}
2287 	}
2288 
2289 	return 0;
2290 }
2291 #else
2292 static int pmbus_init_debugfs(struct i2c_client *client,
2293 			      struct pmbus_data *data)
2294 {
2295 	return 0;
2296 }
2297 #endif	/* IS_ENABLED(CONFIG_DEBUG_FS) */
2298 
2299 int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
2300 		   struct pmbus_driver_info *info)
2301 {
2302 	struct device *dev = &client->dev;
2303 	const struct pmbus_platform_data *pdata = dev_get_platdata(dev);
2304 	struct pmbus_data *data;
2305 	int ret;
2306 
2307 	if (!info)
2308 		return -ENODEV;
2309 
2310 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE
2311 				     | I2C_FUNC_SMBUS_BYTE_DATA
2312 				     | I2C_FUNC_SMBUS_WORD_DATA))
2313 		return -ENODEV;
2314 
2315 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
2316 	if (!data)
2317 		return -ENOMEM;
2318 
2319 	i2c_set_clientdata(client, data);
2320 	mutex_init(&data->update_lock);
2321 	data->dev = dev;
2322 
2323 	if (pdata)
2324 		data->flags = pdata->flags;
2325 	data->info = info;
2326 
2327 	ret = pmbus_init_common(client, data, info);
2328 	if (ret < 0)
2329 		return ret;
2330 
2331 	ret = pmbus_find_attributes(client, data);
2332 	if (ret)
2333 		goto out_kfree;
2334 
2335 	/*
2336 	 * If there are no attributes, something is wrong.
2337 	 * Bail out instead of trying to register nothing.
2338 	 */
2339 	if (!data->num_attributes) {
2340 		dev_err(dev, "No attributes found\n");
2341 		ret = -ENODEV;
2342 		goto out_kfree;
2343 	}
2344 
2345 	data->groups[0] = &data->group;
2346 	data->hwmon_dev = hwmon_device_register_with_groups(dev, client->name,
2347 							    data, data->groups);
2348 	if (IS_ERR(data->hwmon_dev)) {
2349 		ret = PTR_ERR(data->hwmon_dev);
2350 		dev_err(dev, "Failed to register hwmon device\n");
2351 		goto out_kfree;
2352 	}
2353 
2354 	ret = pmbus_regulator_register(data);
2355 	if (ret)
2356 		goto out_unregister;
2357 
2358 	ret = pmbus_init_debugfs(client, data);
2359 	if (ret)
2360 		dev_warn(dev, "Failed to register debugfs\n");
2361 
2362 	return 0;
2363 
2364 out_unregister:
2365 	hwmon_device_unregister(data->hwmon_dev);
2366 out_kfree:
2367 	kfree(data->group.attrs);
2368 	return ret;
2369 }
2370 EXPORT_SYMBOL_GPL(pmbus_do_probe);
2371 
2372 int pmbus_do_remove(struct i2c_client *client)
2373 {
2374 	struct pmbus_data *data = i2c_get_clientdata(client);
2375 
2376 	debugfs_remove_recursive(data->debugfs);
2377 
2378 	hwmon_device_unregister(data->hwmon_dev);
2379 	kfree(data->group.attrs);
2380 	return 0;
2381 }
2382 EXPORT_SYMBOL_GPL(pmbus_do_remove);
2383 
2384 struct dentry *pmbus_get_debugfs_dir(struct i2c_client *client)
2385 {
2386 	struct pmbus_data *data = i2c_get_clientdata(client);
2387 
2388 	return data->debugfs;
2389 }
2390 EXPORT_SYMBOL_GPL(pmbus_get_debugfs_dir);
2391 
2392 static int __init pmbus_core_init(void)
2393 {
2394 	pmbus_debugfs_dir = debugfs_create_dir("pmbus", NULL);
2395 	if (IS_ERR(pmbus_debugfs_dir))
2396 		pmbus_debugfs_dir = NULL;
2397 
2398 	return 0;
2399 }
2400 
2401 static void __exit pmbus_core_exit(void)
2402 {
2403 	debugfs_remove_recursive(pmbus_debugfs_dir);
2404 }
2405 
2406 module_init(pmbus_core_init);
2407 module_exit(pmbus_core_exit);
2408 
2409 MODULE_AUTHOR("Guenter Roeck");
2410 MODULE_DESCRIPTION("PMBus core driver");
2411 MODULE_LICENSE("GPL");
2412