summaryrefslogtreecommitdiff
path: root/drivers/hwmon/pmbus/pmbus_core.c
blob: 80eef50c50fd27f9022f3f3176ff6434ad945867 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
/*
 * Hardware monitoring driver for PMBus devices
 *
 * Copyright (c) 2010, 2011 Ericsson AB.
 * Copyright (c) 2012 Guenter Roeck
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/jiffies.h>
#include <linux/i2c/pmbus.h>
#include "pmbus.h"

/*
 * Number of additional attribute pointers to allocate
 * with each call to krealloc
 */
#define PMBUS_ATTR_ALLOC_SIZE	32

/*
 * Index into status register array, per status register group
 */
#define PB_STATUS_BASE		0
#define PB_STATUS_VOUT_BASE	(PB_STATUS_BASE + PMBUS_PAGES)
#define PB_STATUS_IOUT_BASE	(PB_STATUS_VOUT_BASE + PMBUS_PAGES)
#define PB_STATUS_FAN_BASE	(PB_STATUS_IOUT_BASE + PMBUS_PAGES)
#define PB_STATUS_FAN34_BASE	(PB_STATUS_FAN_BASE + PMBUS_PAGES)
#define PB_STATUS_TEMP_BASE	(PB_STATUS_FAN34_BASE + PMBUS_PAGES)
#define PB_STATUS_INPUT_BASE	(PB_STATUS_TEMP_BASE + PMBUS_PAGES)
#define PB_STATUS_VMON_BASE	(PB_STATUS_INPUT_BASE + 1)

#define PB_NUM_STATUS_REG	(PB_STATUS_VMON_BASE + 1)

#define PMBUS_NAME_SIZE		24

struct pmbus_sensor {
	struct pmbus_sensor *next;
	char name[PMBUS_NAME_SIZE];	/* sysfs sensor name */
	struct device_attribute attribute;
	u8 page;		/* page number */
	u16 reg;		/* register */
	enum pmbus_sensor_classes class;	/* sensor class */
	bool update;		/* runtime sensor update needed */
	int data;		/* Sensor data.
				   Negative if there was a read error */
};
#define to_pmbus_sensor(_attr) \
	container_of(_attr, struct pmbus_sensor, attribute)

struct pmbus_boolean {
	char name[PMBUS_NAME_SIZE];	/* sysfs boolean name */
	struct sensor_device_attribute attribute;
	struct pmbus_sensor *s1;
	struct pmbus_sensor *s2;
};
#define to_pmbus_boolean(_attr) \
	container_of(_attr, struct pmbus_boolean, attribute)

struct pmbus_label {
	char name[PMBUS_NAME_SIZE];	/* sysfs label name */
	struct device_attribute attribute;
	char label[PMBUS_NAME_SIZE];	/* label */
};
#define to_pmbus_label(_attr) \
	container_of(_attr, struct pmbus_label, attribute)

struct pmbus_data {
	struct device *dev;
	struct device *hwmon_dev;

	u32 flags;		/* from platform data */

	int exponent;		/* linear mode: exponent for output voltages */

	const struct pmbus_driver_info *info;

	int max_attributes;
	int num_attributes;
	struct attribute_group group;

	struct pmbus_sensor *sensors;

	struct mutex update_lock;
	bool valid;
	unsigned long last_updated;	/* in jiffies */

	/*
	 * A single status register covers multiple attributes,
	 * so we keep them all together.
	 */
	u8 status[PB_NUM_STATUS_REG];
	u8 status_register;

	u8 currpage;
};

void pmbus_clear_cache(struct i2c_client *client)
{
	struct pmbus_data *data = i2c_get_clientdata(client);

	data->valid = false;
}
EXPORT_SYMBOL_GPL(pmbus_clear_cache);

int pmbus_set_page(struct i2c_client *client, u8 page)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	int rv = 0;
	int newpage;

	if (page != data->currpage) {
		rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
		newpage = i2c_smbus_read_byte_data(client, PMBUS_PAGE);
		if (newpage != page)
			rv = -EIO;
		else
			data->currpage = page;
	}
	return rv;
}
EXPORT_SYMBOL_GPL(pmbus_set_page);

int pmbus_write_byte(struct i2c_client *client, int page, u8 value)
{
	int rv;

	if (page >= 0) {
		rv = pmbus_set_page(client, page);
		if (rv < 0)
			return rv;
	}

	return i2c_smbus_write_byte(client, value);
}
EXPORT_SYMBOL_GPL(pmbus_write_byte);

/*
 * _pmbus_write_byte() is similar to pmbus_write_byte(), but checks if
 * a device specific mapping funcion exists and calls it if necessary.
 */
static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	const struct pmbus_driver_info *info = data->info;
	int status;

	if (info->write_byte) {
		status = info->write_byte(client, page, value);
		if (status != -ENODATA)
			return status;
	}
	return pmbus_write_byte(client, page, value);
}

int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word)
{
	int rv;

	rv = pmbus_set_page(client, page);
	if (rv < 0)
		return rv;

	return i2c_smbus_write_word_data(client, reg, word);
}
EXPORT_SYMBOL_GPL(pmbus_write_word_data);

/*
 * _pmbus_write_word_data() is similar to pmbus_write_word_data(), but checks if
 * a device specific mapping function exists and calls it if necessary.
 */
static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg,
				  u16 word)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	const struct pmbus_driver_info *info = data->info;
	int status;

	if (info->write_word_data) {
		status = info->write_word_data(client, page, reg, word);
		if (status != -ENODATA)
			return status;
	}
	if (reg >= PMBUS_VIRT_BASE)
		return -ENXIO;
	return pmbus_write_word_data(client, page, reg, word);
}

int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg)
{
	int rv;

	rv = pmbus_set_page(client, page);
	if (rv < 0)
		return rv;

	return i2c_smbus_read_word_data(client, reg);
}
EXPORT_SYMBOL_GPL(pmbus_read_word_data);

/*
 * _pmbus_read_word_data() is similar to pmbus_read_word_data(), but checks if
 * a device specific mapping function exists and calls it if necessary.
 */
static int _pmbus_read_word_data(struct i2c_client *client, int page, int reg)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	const struct pmbus_driver_info *info = data->info;
	int status;

	if (info->read_word_data) {
		status = info->read_word_data(client, page, reg);
		if (status != -ENODATA)
			return status;
	}
	if (reg >= PMBUS_VIRT_BASE)
		return -ENXIO;
	return pmbus_read_word_data(client, page, reg);
}

int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg)
{
	int rv;

	if (page >= 0) {
		rv = pmbus_set_page(client, page);
		if (rv < 0)
			return rv;
	}

	return i2c_smbus_read_byte_data(client, reg);
}
EXPORT_SYMBOL_GPL(pmbus_read_byte_data);

/*
 * _pmbus_read_byte_data() is similar to pmbus_read_byte_data(), but checks if
 * a device specific mapping function exists and calls it if necessary.
 */
static int _pmbus_read_byte_data(struct i2c_client *client, int page, int reg)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	const struct pmbus_driver_info *info = data->info;
	int status;

	if (info->read_byte_data) {
		status = info->read_byte_data(client, page, reg);
		if (status != -ENODATA)
			return status;
	}
	return pmbus_read_byte_data(client, page, reg);
}

static void pmbus_clear_fault_page(struct i2c_client *client, int page)
{
	_pmbus_write_byte(client, page, PMBUS_CLEAR_FAULTS);
}

void pmbus_clear_faults(struct i2c_client *client)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	int i;

	for (i = 0; i < data->info->pages; i++)
		pmbus_clear_fault_page(client, i);
}
EXPORT_SYMBOL_GPL(pmbus_clear_faults);

static int pmbus_check_status_cml(struct i2c_client *client)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	int status, status2;

	status = _pmbus_read_byte_data(client, -1, data->status_register);
	if (status < 0 || (status & PB_STATUS_CML)) {
		status2 = _pmbus_read_byte_data(client, -1, PMBUS_STATUS_CML);
		if (status2 < 0 || (status2 & PB_CML_FAULT_INVALID_COMMAND))
			return -EIO;
	}
	return 0;
}

static bool pmbus_check_register(struct i2c_client *client,
				 int (*func)(struct i2c_client *client,
					     int page, int reg),
				 int page, int reg)
{
	int rv;
	struct pmbus_data *data = i2c_get_clientdata(client);

	rv = func(client, page, reg);
	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
		rv = pmbus_check_status_cml(client);
	pmbus_clear_fault_page(client, -1);
	return rv >= 0;
}

bool pmbus_check_byte_register(struct i2c_client *client, int page, int reg)
{
	return pmbus_check_register(client, _pmbus_read_byte_data, page, reg);
}
EXPORT_SYMBOL_GPL(pmbus_check_byte_register);

bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
{
	return pmbus_check_register(client, _pmbus_read_word_data, page, reg);
}
EXPORT_SYMBOL_GPL(pmbus_check_word_register);

const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
{
	struct pmbus_data *data = i2c_get_clientdata(client);

	return data->info;
}
EXPORT_SYMBOL_GPL(pmbus_get_driver_info);

static struct _pmbus_status {
	u32 func;
	u16 base;
	u16 reg;
} pmbus_status[] = {
	{ PMBUS_HAVE_STATUS_VOUT, PB_STATUS_VOUT_BASE, PMBUS_STATUS_VOUT },
	{ PMBUS_HAVE_STATUS_IOUT, PB_STATUS_IOUT_BASE, PMBUS_STATUS_IOUT },
	{ PMBUS_HAVE_STATUS_TEMP, PB_STATUS_TEMP_BASE,
	  PMBUS_STATUS_TEMPERATURE },
	{ PMBUS_HAVE_STATUS_FAN12, PB_STATUS_FAN_BASE, PMBUS_STATUS_FAN_12 },
	{ PMBUS_HAVE_STATUS_FAN34, PB_STATUS_FAN34_BASE, PMBUS_STATUS_FAN_34 },
};

static struct pmbus_data *pmbus_update_device(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct pmbus_data *data = i2c_get_clientdata(client);
	const struct pmbus_driver_info *info = data->info;
	struct pmbus_sensor *sensor;

	mutex_lock(&data->update_lock);
	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
		int i, j;

		for (i = 0; i < info->pages; i++) {
			data->status[PB_STATUS_BASE + i]
			    = _pmbus_read_byte_data(client, i,
						    data->status_register);
			for (j = 0; j < ARRAY_SIZE(pmbus_status); j++) {
				struct _pmbus_status *s = &pmbus_status[j];

				if (!(info->func[i] & s->func))
					continue;
				data->status[s->base + i]
					= _pmbus_read_byte_data(client, i,
								s->reg);
			}
		}

		if (info->func[0] & PMBUS_HAVE_STATUS_INPUT)
			data->status[PB_STATUS_INPUT_BASE]
			  = _pmbus_read_byte_data(client, 0,
						  PMBUS_STATUS_INPUT);

		if (info->func[0] & PMBUS_HAVE_STATUS_VMON)
			data->status[PB_STATUS_VMON_BASE]
			  = _pmbus_read_byte_data(client, 0,
						  PMBUS_VIRT_STATUS_VMON);

		for (sensor = data->sensors; sensor; sensor = sensor->next) {
			if (!data->valid || sensor->update)
				sensor->data
				    = _pmbus_read_word_data(client,
							    sensor->page,
							    sensor->reg);
		}
		pmbus_clear_faults(client);
		data->last_updated = jiffies;
		data->valid = 1;
	}
	mutex_unlock(&data->update_lock);
	return data;
}

/*
 * Convert linear sensor values to milli- or micro-units
 * depending on sensor type.
 */
static long pmbus_reg2data_linear(struct pmbus_data *data,
				  struct pmbus_sensor *sensor)
{
	s16 exponent;
	s32 mantissa;
	long val;

	if (sensor->class == PSC_VOLTAGE_OUT) {	/* LINEAR16 */
		exponent = data->exponent;
		mantissa = (u16) sensor->data;
	} else {				/* LINEAR11 */
		exponent = ((s16)sensor->data) >> 11;
		mantissa = ((s16)((sensor->data & 0x7ff) << 5)) >> 5;
	}

	val = mantissa;

	/* scale result to milli-units for all sensors except fans */
	if (sensor->class != PSC_FAN)
		val = val * 1000L;

	/* scale result to micro-units for power sensors */
	if (sensor->class == PSC_POWER)
		val = val * 1000L;

	if (exponent >= 0)
		val <<= exponent;
	else
		val >>= -exponent;

	return val;
}

/*
 * Convert direct sensor values to milli- or micro-units
 * depending on sensor type.
 */
static long pmbus_reg2data_direct(struct pmbus_data *data,
				  struct pmbus_sensor *sensor)
{
	long val = (s16) sensor->data;
	long m, b, R;

	m = data->info->m[sensor->class];
	b = data->info->b[sensor->class];
	R = data->info->R[sensor->class];

	if (m == 0)
		return 0;

	/* X = 1/m * (Y * 10^-R - b) */
	R = -R;
	/* scale result to milli-units for everything but fans */
	if (sensor->class != PSC_FAN) {
		R += 3;
		b *= 1000;
	}

	/* scale result to micro-units for power sensors */
	if (sensor->class == PSC_POWER) {
		R += 3;
		b *= 1000;
	}

	while (R > 0) {
		val *= 10;
		R--;
	}
	while (R < 0) {
		val = DIV_ROUND_CLOSEST(val, 10);
		R++;
	}

	return (val - b) / m;
}

/*
 * Convert VID sensor values to milli- or micro-units
 * depending on sensor type.
 * We currently only support VR11.
 */
static long pmbus_reg2data_vid(struct pmbus_data *data,
			       struct pmbus_sensor *sensor)
{
	long val = sensor->data;

	if (val < 0x02 || val > 0xb2)
		return 0;
	return DIV_ROUND_CLOSEST(160000 - (val - 2) * 625, 100);
}

static long pmbus_reg2data(struct pmbus_data *data, struct pmbus_sensor *sensor)
{
	long val;

	switch (data->info->format[sensor->class]) {
	case direct:
		val = pmbus_reg2data_direct(data, sensor);
		break;
	case vid:
		val = pmbus_reg2data_vid(data, sensor);
		break;
	case linear:
	default:
		val = pmbus_reg2data_linear(data, sensor);
		break;
	}
	return val;
}

#define MAX_MANTISSA	(1023 * 1000)
#define MIN_MANTISSA	(511 * 1000)

static u16 pmbus_data2reg_linear(struct pmbus_data *data,
				 enum pmbus_sensor_classes class, long val)
{
	s16 exponent = 0, mantissa;
	bool negative = false;

	/* simple case */
	if (val == 0)
		return 0;

	if (class == PSC_VOLTAGE_OUT) {
		/* LINEAR16 does not support negative voltages */
		if (val < 0)
			return 0;

		/*
		 * For a static exponents, we don't have a choice
		 * but to adjust the value to it.
		 */
		if (data->exponent < 0)
			val <<= -data->exponent;
		else
			val >>= data->exponent;
		val = DIV_ROUND_CLOSEST(val, 1000);
		return val & 0xffff;
	}

	if (val < 0) {
		negative = true;
		val = -val;
	}

	/* Power is in uW. Convert to mW before converting. */
	if (class == PSC_POWER)
		val = DIV_ROUND_CLOSEST(val, 1000L);

	/*
	 * For simplicity, convert fan data to milli-units
	 * before calculating the exponent.
	 */
	if (class == PSC_FAN)
		val = val * 1000;

	/* Reduce large mantissa until it fits into 10 bit */
	while (val >= MAX_MANTISSA && exponent < 15) {
		exponent++;
		val >>= 1;
	}
	/* Increase small mantissa to improve precision */
	while (val < MIN_MANTISSA && exponent > -15) {
		exponent--;
		val <<= 1;
	}

	/* Convert mantissa from milli-units to units */
	mantissa = DIV_ROUND_CLOSEST(val, 1000);

	/* Ensure that resulting number is within range */
	if (mantissa > 0x3ff)
		mantissa = 0x3ff;

	/* restore sign */
	if (negative)
		mantissa = -mantissa;

	/* Convert to 5 bit exponent, 11 bit mantissa */
	return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
}

static u16 pmbus_data2reg_direct(struct pmbus_data *data,
				 enum pmbus_sensor_classes class, long val)
{
	long m, b, R;

	m = data->info->m[class];
	b = data->info->b[class];
	R = data->info->R[class];

	/* Power is in uW. Adjust R and b. */
	if (class == PSC_POWER) {
		R -= 3;
		b *= 1000;
	}

	/* Calculate Y = (m * X + b) * 10^R */
	if (class != PSC_FAN) {
		R -= 3;		/* Adjust R and b for data in milli-units */
		b *= 1000;
	}
	val = val * m + b;

	while (R > 0) {
		val *= 10;
		R--;
	}
	while (R < 0) {
		val = DIV_ROUND_CLOSEST(val, 10);
		R++;
	}

	return val;
}

static u16 pmbus_data2reg_vid(struct pmbus_data *data,
			      enum pmbus_sensor_classes class, long val)
{
	val = clamp_val(val, 500, 1600);

	return 2 + DIV_ROUND_CLOSEST((1600 - val) * 100, 625);
}

static u16 pmbus_data2reg(struct pmbus_data *data,
			  enum pmbus_sensor_classes class, long val)
{
	u16 regval;

	switch (data->info->format[class]) {
	case direct:
		regval = pmbus_data2reg_direct(data, class, val);
		break;
	case vid:
		regval = pmbus_data2reg_vid(data, class, val);
		break;
	case linear:
	default:
		regval = pmbus_data2reg_linear(data, class, val);
		break;
	}
	return regval;
}

/*
 * Return boolean calculated from converted data.
 * <index> defines a status register index and mask.
 * The mask is in the lower 8 bits, the register index is in bits 8..23.
 *
 * The associated pmbus_boolean structure contains optional pointers to two
 * sensor attributes. If specified, those attributes are compared against each
 * other to determine if a limit has been exceeded.
 *
 * If the sensor attribute pointers are NULL, the function returns true if
 * (status[reg] & mask) is true.
 *
 * If sensor attribute pointers are provided, a comparison against a specified
 * limit has to be performed to determine the boolean result.
 * In this case, the function returns true if v1 >= v2 (where v1 and v2 are
 * sensor values referenced by sensor attribute pointers s1 and s2).
 *
 * To determine if an object exceeds upper limits, specify <s1,s2> = <v,limit>.
 * To determine if an object exceeds lower limits, specify <s1,s2> = <limit,v>.
 *
 * If a negative value is stored in any of the referenced registers, this value
 * reflects an error code which will be returned.
 */
static int pmbus_get_boolean(struct pmbus_data *data, struct pmbus_boolean *b,
			     int index)
{
	struct pmbus_sensor *s1 = b->s1;
	struct pmbus_sensor *s2 = b->s2;
	u16 reg = (index >> 8) & 0xffff;
	u8 mask = index & 0xff;
	int ret, status;
	u8 regval;

	status = data->status[reg];
	if (status < 0)
		return status;

	regval = status & mask;
	if (!s1 && !s2) {
		ret = !!regval;
	} else if (!s1 || !s2) {
		BUG();
		return 0;
	} else {
		long v1, v2;

		if (s1->data < 0)
			return s1->data;
		if (s2->data < 0)
			return s2->data;

		v1 = pmbus_reg2data(data, s1);
		v2 = pmbus_reg2data(data, s2);
		ret = !!(regval && v1 >= v2);
	}
	return ret;
}

static ssize_t pmbus_show_boolean(struct device *dev,
				  struct device_attribute *da, char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct pmbus_boolean *boolean = to_pmbus_boolean(attr);
	struct pmbus_data *data = pmbus_update_device(dev);
	int val;

	val = pmbus_get_boolean(data, boolean, attr->index);
	if (val < 0)
		return val;
	return snprintf(buf, PAGE_SIZE, "%d\n", val);
}

static ssize_t pmbus_show_sensor(struct device *dev,
				 struct device_attribute *devattr, char *buf)
{
	struct pmbus_data *data = pmbus_update_device(dev);
	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);

	if (sensor->data < 0)
		return sensor->data;

	return snprintf(buf, PAGE_SIZE, "%ld\n", pmbus_reg2data(data, sensor));
}

static ssize_t pmbus_set_sensor(struct device *dev,
				struct device_attribute *devattr,
				const char *buf, size_t count)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct pmbus_data *data = i2c_get_clientdata(client);
	struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
	ssize_t rv = count;
	long val = 0;
	int ret;
	u16 regval;

	if (kstrtol(buf, 10, &val) < 0)
		return -EINVAL;

	mutex_lock(&data->update_lock);
	regval = pmbus_data2reg(data, sensor->class, val);
	ret = _pmbus_write_word_data(client, sensor->page, sensor->reg, regval);
	if (ret < 0)
		rv = ret;
	else
		sensor->data = regval;
	mutex_unlock(&data->update_lock);
	return rv;
}

static ssize_t pmbus_show_label(struct device *dev,
				struct device_attribute *da, char *buf)
{
	struct pmbus_label *label = to_pmbus_label(da);

	return snprintf(buf, PAGE_SIZE, "%s\n", label->label);
}

static int pmbus_add_attribute(struct pmbus_data *data, struct attribute *attr)
{
	if (data->num_attributes >= data->max_attributes - 1) {
		data->max_attributes += PMBUS_ATTR_ALLOC_SIZE;
		data->group.attrs = krealloc(data->group.attrs,
					     sizeof(struct attribute *) *
					     data->max_attributes, GFP_KERNEL);
		if (data->group.attrs == NULL)
			return -ENOMEM;
	}

	data->group.attrs[data->num_attributes++] = attr;
	data->group.attrs[data->num_attributes] = NULL;
	return 0;
}

static void pmbus_dev_attr_init(struct device_attribute *dev_attr,
				const char *name,
				umode_t mode,
				ssize_t (*show)(struct device *dev,
						struct device_attribute *attr,
						char *buf),
				ssize_t (*store)(struct device *dev,
						 struct device_attribute *attr,
						 const char *buf, size_t count))
{
	sysfs_attr_init(&dev_attr->attr);
	dev_attr->attr.name = name;
	dev_attr->attr.mode = mode;
	dev_attr->show = show;
	dev_attr->store = store;
}

static void pmbus_attr_init(struct sensor_device_attribute *a,
			    const char *name,
			    umode_t mode,
			    ssize_t (*show)(struct device *dev,
					    struct device_attribute *attr,
					    char *buf),
			    ssize_t (*store)(struct device *dev,
					     struct device_attribute *attr,
					     const char *buf, size_t count),
			    int idx)
{
	pmbus_dev_attr_init(&a->dev_attr, name, mode, show, store);
	a->index = idx;
}

static int pmbus_add_boolean(struct pmbus_data *data,
			     const char *name, const char *type, int seq,
			     struct pmbus_sensor *s1,
			     struct pmbus_sensor *s2,
			     u16 reg, u8 mask)
{
	struct pmbus_boolean *boolean;
	struct sensor_device_attribute *a;

	boolean = devm_kzalloc(data->dev, sizeof(*boolean), GFP_KERNEL);
	if (!boolean)
		return -ENOMEM;

	a = &boolean->attribute;

	snprintf(boolean->name, sizeof(boolean->name), "%s%d_%s",
		 name, seq, type);
	boolean->s1 = s1;
	boolean->s2 = s2;
	pmbus_attr_init(a, boolean->name, S_IRUGO, pmbus_show_boolean, NULL,
			(reg << 8) | mask);

	return pmbus_add_attribute(data, &a->dev_attr.attr);
}

static struct pmbus_sensor *pmbus_add_sensor(struct pmbus_data *data,
					     const char *name, const char *type,
					     int seq, int page, int reg,
					     enum pmbus_sensor_classes class,
					     bool update, bool readonly)
{
	struct pmbus_sensor *sensor;
	struct device_attribute *a;

	sensor = devm_kzalloc(data->dev, sizeof(*sensor), GFP_KERNEL);
	if (!sensor)
		return NULL;
	a = &sensor->attribute;

	snprintf(sensor->name, sizeof(sensor->name), "%s%d_%s",
		 name, seq, type);
	sensor->page = page;
	sensor->reg = reg;
	sensor->class = class;
	sensor->update = update;
	pmbus_dev_attr_init(a, sensor->name,
			    readonly ? S_IRUGO : S_IRUGO | S_IWUSR,
			    pmbus_show_sensor, pmbus_set_sensor);

	if (pmbus_add_attribute(data, &a->attr))
		return NULL;

	sensor->next = data->sensors;
	data->sensors = sensor;

	return sensor;
}

static int pmbus_add_label(struct pmbus_data *data,
			   const char *name, int seq,
			   const char *lstring, int index)
{
	struct pmbus_label *label;
	struct device_attribute *a;

	label = devm_kzalloc(data->dev, sizeof(*label), GFP_KERNEL);
	if (!label)
		return -ENOMEM;

	a = &label->attribute;

	snprintf(label->name, sizeof(label->name), "%s%d_label", name, seq);
	if (!index)
		strncpy(label->label, lstring, sizeof(label->label) - 1);
	else
		snprintf(label->label, sizeof(label->label), "%s%d", lstring,
			 index);

	pmbus_dev_attr_init(a, label->name, S_IRUGO, pmbus_show_label, NULL);
	return pmbus_add_attribute(data, &a->attr);
}

/*
 * Search for attributes. Allocate sensors, booleans, and labels as needed.
 */

/*
 * The pmbus_limit_attr structure describes a single limit attribute
 * and its associated alarm attribute.
 */
struct pmbus_limit_attr {
	u16 reg;		/* Limit register */
	u16 sbit;		/* Alarm attribute status bit */
	bool update;		/* True if register needs updates */
	bool low;		/* True if low limit; for limits with compare
				   functions only */
	const char *attr;	/* Attribute name */
	const char *alarm;	/* Alarm attribute name */
};

/*
 * The pmbus_sensor_attr structure describes one sensor attribute. This
 * description includes a reference to the associated limit attributes.
 */
struct pmbus_sensor_attr {
	u16 reg;			/* sensor register */
	u8 gbit;			/* generic status bit */
	u8 nlimit;			/* # of limit registers */
	enum pmbus_sensor_classes class;/* sensor class */
	const char *label;		/* sensor label */
	bool paged;			/* true if paged sensor */
	bool update;			/* true if update needed */
	bool compare;			/* true if compare function needed */
	u32 func;			/* sensor mask */
	u32 sfunc;			/* sensor status mask */
	int sbase;			/* status base register */
	const struct pmbus_limit_attr *limit;/* limit registers */
};

/*
 * Add a set of limit attributes and, if supported, the associated
 * alarm attributes.
 * returns 0 if no alarm register found, 1 if an alarm register was found,
 * < 0 on errors.
 */
static int pmbus_add_limit_attrs(struct i2c_client *client,
				 struct pmbus_data *data,
				 const struct pmbus_driver_info *info,
				 const char *name, int index, int page,
				 struct pmbus_sensor *base,
				 const struct pmbus_sensor_attr *attr)
{
	const struct pmbus_limit_attr *l = attr->limit;
	int nlimit = attr->nlimit;
	int have_alarm = 0;
	int i, ret;
	struct pmbus_sensor *curr;

	for (i = 0; i < nlimit; i++) {
		if (pmbus_check_word_register(client, page, l->reg)) {
			curr = pmbus_add_sensor(data, name, l->attr, index,
						page, l->reg, attr->class,
						attr->update || l->update,
						false);
			if (!curr)
				return -ENOMEM;
			if (l->sbit && (info->func[page] & attr->sfunc)) {
				ret = pmbus_add_boolean(data, name,
					l->alarm, index,
					attr->compare ?  l->low ? curr : base
						      : NULL,
					attr->compare ? l->low ? base : curr
						      : NULL,
					attr->sbase + page, l->sbit);
				if (ret)
					return ret;
				have_alarm = 1;
			}
		}
		l++;
	}
	return have_alarm;
}

static int pmbus_add_sensor_attrs_one(struct i2c_client *client,
				      struct pmbus_data *data,
				      const struct pmbus_driver_info *info,
				      const char *name,
				      int index, int page,
				      const struct pmbus_sensor_attr *attr)
{
	struct pmbus_sensor *base;
	int ret;

	if (attr->label) {
		ret = pmbus_add_label(data, name, index, attr->label,
				      attr->paged ? page + 1 : 0);
		if (ret)
			return ret;
	}
	base = pmbus_add_sensor(data, name, "input", index, page, attr->reg,
				attr->class, true, true);
	if (!base)
		return -ENOMEM;
	if (attr->sfunc) {
		ret = pmbus_add_limit_attrs(client, data, info, name,
					    index, page, base, attr);
		if (ret < 0)
			return ret;
		/*
		 * Add generic alarm attribute only if there are no individual
		 * alarm attributes, if there is a global alarm bit, and if
		 * the generic status register for this page is accessible.
		 */
		if (!ret && attr->gbit &&
		    pmbus_check_byte_register(client, page,
					      data->status_register)) {
			ret = pmbus_add_boolean(data, name, "alarm", index,
						NULL, NULL,
						PB_STATUS_BASE + page,
						attr->gbit);
			if (ret)
				return ret;
		}
	}
	return 0;
}

static int pmbus_add_sensor_attrs(struct i2c_client *client,
				  struct pmbus_data *data,
				  const char *name,
				  const struct pmbus_sensor_attr *attrs,
				  int nattrs)
{
	const struct pmbus_driver_info *info = data->info;
	int index, i;
	int ret;

	index = 1;
	for (i = 0; i < nattrs; i++) {
		int page, pages;

		pages = attrs->paged ? info->pages : 1;
		for (page = 0; page < pages; page++) {
			if (!(info->func[page] & attrs->func))
				continue;
			ret = pmbus_add_sensor_attrs_one(client, data, info,
							 name, index, page,
							 attrs);
			if (ret)
				return ret;
			index++;
		}
		attrs++;
	}
	return 0;
}

static const struct pmbus_limit_attr vin_limit_attrs[] = {
	{
		.reg = PMBUS_VIN_UV_WARN_LIMIT,
		.attr = "min",
		.alarm = "min_alarm",
		.sbit = PB_VOLTAGE_UV_WARNING,
	}, {
		.reg = PMBUS_VIN_UV_FAULT_LIMIT,
		.attr = "lcrit",
		.alarm = "lcrit_alarm",
		.sbit = PB_VOLTAGE_UV_FAULT,
	}, {
		.reg = PMBUS_VIN_OV_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_VOLTAGE_OV_WARNING,
	}, {
		.reg = PMBUS_VIN_OV_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_VOLTAGE_OV_FAULT,
	}, {
		.reg = PMBUS_VIRT_READ_VIN_AVG,
		.update = true,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_VIN_MIN,
		.update = true,
		.attr = "lowest",
	}, {
		.reg = PMBUS_VIRT_READ_VIN_MAX,
		.update = true,
		.attr = "highest",
	}, {
		.reg = PMBUS_VIRT_RESET_VIN_HISTORY,
		.attr = "reset_history",
	},
};

static const struct pmbus_limit_attr vmon_limit_attrs[] = {
	{
		.reg = PMBUS_VIRT_VMON_UV_WARN_LIMIT,
		.attr = "min",
		.alarm = "min_alarm",
		.sbit = PB_VOLTAGE_UV_WARNING,
	}, {
		.reg = PMBUS_VIRT_VMON_UV_FAULT_LIMIT,
		.attr = "lcrit",
		.alarm = "lcrit_alarm",
		.sbit = PB_VOLTAGE_UV_FAULT,
	}, {
		.reg = PMBUS_VIRT_VMON_OV_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_VOLTAGE_OV_WARNING,
	}, {
		.reg = PMBUS_VIRT_VMON_OV_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_VOLTAGE_OV_FAULT,
	}
};

static const struct pmbus_limit_attr vout_limit_attrs[] = {
	{
		.reg = PMBUS_VOUT_UV_WARN_LIMIT,
		.attr = "min",
		.alarm = "min_alarm",
		.sbit = PB_VOLTAGE_UV_WARNING,
	}, {
		.reg = PMBUS_VOUT_UV_FAULT_LIMIT,
		.attr = "lcrit",
		.alarm = "lcrit_alarm",
		.sbit = PB_VOLTAGE_UV_FAULT,
	}, {
		.reg = PMBUS_VOUT_OV_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_VOLTAGE_OV_WARNING,
	}, {
		.reg = PMBUS_VOUT_OV_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_VOLTAGE_OV_FAULT,
	}, {
		.reg = PMBUS_VIRT_READ_VOUT_AVG,
		.update = true,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_VOUT_MIN,
		.update = true,
		.attr = "lowest",
	}, {
		.reg = PMBUS_VIRT_READ_VOUT_MAX,
		.update = true,
		.attr = "highest",
	}, {
		.reg = PMBUS_VIRT_RESET_VOUT_HISTORY,
		.attr = "reset_history",
	}
};

static const struct pmbus_sensor_attr voltage_attributes[] = {
	{
		.reg = PMBUS_READ_VIN,
		.class = PSC_VOLTAGE_IN,
		.label = "vin",
		.func = PMBUS_HAVE_VIN,
		.sfunc = PMBUS_HAVE_STATUS_INPUT,
		.sbase = PB_STATUS_INPUT_BASE,
		.gbit = PB_STATUS_VIN_UV,
		.limit = vin_limit_attrs,
		.nlimit = ARRAY_SIZE(vin_limit_attrs),
	}, {
		.reg = PMBUS_VIRT_READ_VMON,
		.class = PSC_VOLTAGE_IN,
		.label = "vmon",
		.func = PMBUS_HAVE_VMON,
		.sfunc = PMBUS_HAVE_STATUS_VMON,
		.sbase = PB_STATUS_VMON_BASE,
		.limit = vmon_limit_attrs,
		.nlimit = ARRAY_SIZE(vmon_limit_attrs),
	}, {
		.reg = PMBUS_READ_VCAP,
		.class = PSC_VOLTAGE_IN,
		.label = "vcap",
		.func = PMBUS_HAVE_VCAP,
	}, {
		.reg = PMBUS_READ_VOUT,
		.class = PSC_VOLTAGE_OUT,
		.label = "vout",
		.paged = true,
		.func = PMBUS_HAVE_VOUT,
		.sfunc = PMBUS_HAVE_STATUS_VOUT,
		.sbase = PB_STATUS_VOUT_BASE,
		.gbit = PB_STATUS_VOUT_OV,
		.limit = vout_limit_attrs,
		.nlimit = ARRAY_SIZE(vout_limit_attrs),
	}
};

/* Current attributes */

static const struct pmbus_limit_attr iin_limit_attrs[] = {
	{
		.reg = PMBUS_IIN_OC_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_IIN_OC_WARNING,
	}, {
		.reg = PMBUS_IIN_OC_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_IIN_OC_FAULT,
	}, {
		.reg = PMBUS_VIRT_READ_IIN_AVG,
		.update = true,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_IIN_MIN,
		.update = true,
		.attr = "lowest",
	}, {
		.reg = PMBUS_VIRT_READ_IIN_MAX,
		.update = true,
		.attr = "highest",
	}, {
		.reg = PMBUS_VIRT_RESET_IIN_HISTORY,
		.attr = "reset_history",
	}
};

static const struct pmbus_limit_attr iout_limit_attrs[] = {
	{
		.reg = PMBUS_IOUT_OC_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_IOUT_OC_WARNING,
	}, {
		.reg = PMBUS_IOUT_UC_FAULT_LIMIT,
		.attr = "lcrit",
		.alarm = "lcrit_alarm",
		.sbit = PB_IOUT_UC_FAULT,
	}, {
		.reg = PMBUS_IOUT_OC_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_IOUT_OC_FAULT,
	}, {
		.reg = PMBUS_VIRT_READ_IOUT_AVG,
		.update = true,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_IOUT_MIN,
		.update = true,
		.attr = "lowest",
	}, {
		.reg = PMBUS_VIRT_READ_IOUT_MAX,
		.update = true,
		.attr = "highest",
	}, {
		.reg = PMBUS_VIRT_RESET_IOUT_HISTORY,
		.attr = "reset_history",
	}
};

static const struct pmbus_sensor_attr current_attributes[] = {
	{
		.reg = PMBUS_READ_IIN,
		.class = PSC_CURRENT_IN,
		.label = "iin",
		.func = PMBUS_HAVE_IIN,
		.sfunc = PMBUS_HAVE_STATUS_INPUT,
		.sbase = PB_STATUS_INPUT_BASE,
		.limit = iin_limit_attrs,
		.nlimit = ARRAY_SIZE(iin_limit_attrs),
	}, {
		.reg = PMBUS_READ_IOUT,
		.class = PSC_CURRENT_OUT,
		.label = "iout",
		.paged = true,
		.func = PMBUS_HAVE_IOUT,
		.sfunc = PMBUS_HAVE_STATUS_IOUT,
		.sbase = PB_STATUS_IOUT_BASE,
		.gbit = PB_STATUS_IOUT_OC,
		.limit = iout_limit_attrs,
		.nlimit = ARRAY_SIZE(iout_limit_attrs),
	}
};

/* Power attributes */

static const struct pmbus_limit_attr pin_limit_attrs[] = {
	{
		.reg = PMBUS_PIN_OP_WARN_LIMIT,
		.attr = "max",
		.alarm = "alarm",
		.sbit = PB_PIN_OP_WARNING,
	}, {
		.reg = PMBUS_VIRT_READ_PIN_AVG,
		.update = true,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_PIN_MAX,
		.update = true,
		.attr = "input_highest",
	}, {
		.reg = PMBUS_VIRT_RESET_PIN_HISTORY,
		.attr = "reset_history",
	}
};

static const struct pmbus_limit_attr pout_limit_attrs[] = {
	{
		.reg = PMBUS_POUT_MAX,
		.attr = "cap",
		.alarm = "cap_alarm",
		.sbit = PB_POWER_LIMITING,
	}, {
		.reg = PMBUS_POUT_OP_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_POUT_OP_WARNING,
	}, {
		.reg = PMBUS_POUT_OP_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_POUT_OP_FAULT,
	}, {
		.reg = PMBUS_VIRT_READ_POUT_AVG,
		.update = true,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_POUT_MAX,
		.update = true,
		.attr = "input_highest",
	}, {
		.reg = PMBUS_VIRT_RESET_POUT_HISTORY,
		.attr = "reset_history",
	}
};

static const struct pmbus_sensor_attr power_attributes[] = {
	{
		.reg = PMBUS_READ_PIN,
		.class = PSC_POWER,
		.label = "pin",
		.func = PMBUS_HAVE_PIN,
		.sfunc = PMBUS_HAVE_STATUS_INPUT,
		.sbase = PB_STATUS_INPUT_BASE,
		.limit = pin_limit_attrs,
		.nlimit = ARRAY_SIZE(pin_limit_attrs),
	}, {
		.reg = PMBUS_READ_POUT,
		.class = PSC_POWER,
		.label = "pout",
		.paged = true,
		.func = PMBUS_HAVE_POUT,
		.sfunc = PMBUS_HAVE_STATUS_IOUT,
		.sbase = PB_STATUS_IOUT_BASE,
		.limit = pout_limit_attrs,
		.nlimit = ARRAY_SIZE(pout_limit_attrs),
	}
};

/* Temperature atributes */

static const struct pmbus_limit_attr temp_limit_attrs[] = {
	{
		.reg = PMBUS_UT_WARN_LIMIT,
		.low = true,
		.attr = "min",
		.alarm = "min_alarm",
		.sbit = PB_TEMP_UT_WARNING,
	}, {
		.reg = PMBUS_UT_FAULT_LIMIT,
		.low = true,
		.attr = "lcrit",
		.alarm = "lcrit_alarm",
		.sbit = PB_TEMP_UT_FAULT,
	}, {
		.reg = PMBUS_OT_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_TEMP_OT_WARNING,
	}, {
		.reg = PMBUS_OT_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_TEMP_OT_FAULT,
	}, {
		.reg = PMBUS_VIRT_READ_TEMP_MIN,
		.attr = "lowest",
	}, {
		.reg = PMBUS_VIRT_READ_TEMP_AVG,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_TEMP_MAX,
		.attr = "highest",
	}, {
		.reg = PMBUS_VIRT_RESET_TEMP_HISTORY,
		.attr = "reset_history",
	}
};

static const struct pmbus_limit_attr temp_limit_attrs2[] = {
	{
		.reg = PMBUS_UT_WARN_LIMIT,
		.low = true,
		.attr = "min",
		.alarm = "min_alarm",
		.sbit = PB_TEMP_UT_WARNING,
	}, {
		.reg = PMBUS_UT_FAULT_LIMIT,
		.low = true,
		.attr = "lcrit",
		.alarm = "lcrit_alarm",
		.sbit = PB_TEMP_UT_FAULT,
	}, {
		.reg = PMBUS_OT_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_TEMP_OT_WARNING,
	}, {
		.reg = PMBUS_OT_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_TEMP_OT_FAULT,
	}, {
		.reg = PMBUS_VIRT_READ_TEMP2_MIN,
		.attr = "lowest",
	}, {
		.reg = PMBUS_VIRT_READ_TEMP2_AVG,
		.attr = "average",
	}, {
		.reg = PMBUS_VIRT_READ_TEMP2_MAX,
		.attr = "highest",
	}, {
		.reg = PMBUS_VIRT_RESET_TEMP2_HISTORY,
		.attr = "reset_history",
	}
};

static const struct pmbus_limit_attr temp_limit_attrs3[] = {
	{
		.reg = PMBUS_UT_WARN_LIMIT,
		.low = true,
		.attr = "min",
		.alarm = "min_alarm",
		.sbit = PB_TEMP_UT_WARNING,
	}, {
		.reg = PMBUS_UT_FAULT_LIMIT,
		.low = true,
		.attr = "lcrit",
		.alarm = "lcrit_alarm",
		.sbit = PB_TEMP_UT_FAULT,
	}, {
		.reg = PMBUS_OT_WARN_LIMIT,
		.attr = "max",
		.alarm = "max_alarm",
		.sbit = PB_TEMP_OT_WARNING,
	}, {
		.reg = PMBUS_OT_FAULT_LIMIT,
		.attr = "crit",
		.alarm = "crit_alarm",
		.sbit = PB_TEMP_OT_FAULT,
	}
};

static const struct pmbus_sensor_attr temp_attributes[] = {
	{
		.reg = PMBUS_READ_TEMPERATURE_1,
		.class = PSC_TEMPERATURE,
		.paged = true,
		.update = true,
		.compare = true,
		.func = PMBUS_HAVE_TEMP,
		.sfunc = PMBUS_HAVE_STATUS_TEMP,
		.sbase = PB_STATUS_TEMP_BASE,
		.gbit = PB_STATUS_TEMPERATURE,
		.limit = temp_limit_attrs,
		.nlimit = ARRAY_SIZE(temp_limit_attrs),
	}, {
		.reg = PMBUS_READ_TEMPERATURE_2,
		.class = PSC_TEMPERATURE,
		.paged = true,
		.update = true,
		.compare = true,
		.func = PMBUS_HAVE_TEMP2,
		.sfunc = PMBUS_HAVE_STATUS_TEMP,
		.sbase = PB_STATUS_TEMP_BASE,
		.gbit = PB_STATUS_TEMPERATURE,
		.limit = temp_limit_attrs2,
		.nlimit = ARRAY_SIZE(temp_limit_attrs2),
	}, {
		.reg = PMBUS_READ_TEMPERATURE_3,
		.class = PSC_TEMPERATURE,
		.paged = true,
		.update = true,
		.compare = true,
		.func = PMBUS_HAVE_TEMP3,
		.sfunc = PMBUS_HAVE_STATUS_TEMP,
		.sbase = PB_STATUS_TEMP_BASE,
		.gbit = PB_STATUS_TEMPERATURE,
		.limit = temp_limit_attrs3,
		.nlimit = ARRAY_SIZE(temp_limit_attrs3),
	}
};

static const int pmbus_fan_registers[] = {
	PMBUS_READ_FAN_SPEED_1,
	PMBUS_READ_FAN_SPEED_2,
	PMBUS_READ_FAN_SPEED_3,
	PMBUS_READ_FAN_SPEED_4
};

static const int pmbus_fan_config_registers[] = {
	PMBUS_FAN_CONFIG_12,
	PMBUS_FAN_CONFIG_12,
	PMBUS_FAN_CONFIG_34,
	PMBUS_FAN_CONFIG_34
};

static const int pmbus_fan_status_registers[] = {
	PMBUS_STATUS_FAN_12,
	PMBUS_STATUS_FAN_12,
	PMBUS_STATUS_FAN_34,
	PMBUS_STATUS_FAN_34
};

static const u32 pmbus_fan_flags[] = {
	PMBUS_HAVE_FAN12,
	PMBUS_HAVE_FAN12,
	PMBUS_HAVE_FAN34,
	PMBUS_HAVE_FAN34
};

static const u32 pmbus_fan_status_flags[] = {
	PMBUS_HAVE_STATUS_FAN12,
	PMBUS_HAVE_STATUS_FAN12,
	PMBUS_HAVE_STATUS_FAN34,
	PMBUS_HAVE_STATUS_FAN34
};

/* Fans */
static int pmbus_add_fan_attributes(struct i2c_client *client,
				    struct pmbus_data *data)
{
	const struct pmbus_driver_info *info = data->info;
	int index = 1;
	int page;
	int ret;

	for (page = 0; page < info->pages; page++) {
		int f;

		for (f = 0; f < ARRAY_SIZE(pmbus_fan_registers); f++) {
			int regval;

			if (!(info->func[page] & pmbus_fan_flags[f]))
				break;

			if (!pmbus_check_word_register(client, page,
						       pmbus_fan_registers[f]))
				break;

			/*
			 * Skip fan if not installed.
			 * Each fan configuration register covers multiple fans,
			 * so we have to do some magic.
			 */
			regval = _pmbus_read_byte_data(client, page,
				pmbus_fan_config_registers[f]);
			if (regval < 0 ||
			    (!(regval & (PB_FAN_1_INSTALLED >> ((f & 1) * 4)))))
				continue;

			if (pmbus_add_sensor(data, "fan", "input", index,
					     page, pmbus_fan_registers[f],
					     PSC_FAN, true, true) == NULL)
				return -ENOMEM;

			/*
			 * Each fan status register covers multiple fans,
			 * so we have to do some magic.
			 */
			if ((info->func[page] & pmbus_fan_status_flags[f]) &&
			    pmbus_check_byte_register(client,
					page, pmbus_fan_status_registers[f])) {
				int base;

				if (f > 1)	/* fan 3, 4 */
					base = PB_STATUS_FAN34_BASE + page;
				else
					base = PB_STATUS_FAN_BASE + page;
				ret = pmbus_add_boolean(data, "fan",
					"alarm", index, NULL, NULL, base,
					PB_FAN_FAN1_WARNING >> (f & 1));
				if (ret)
					return ret;
				ret = pmbus_add_boolean(data, "fan",
					"fault", index, NULL, NULL, base,
					PB_FAN_FAN1_FAULT >> (f & 1));
				if (ret)
					return ret;
			}
			index++;
		}
	}
	return 0;
}

static int pmbus_find_attributes(struct i2c_client *client,
				 struct pmbus_data *data)
{
	int ret;

	/* Voltage sensors */
	ret = pmbus_add_sensor_attrs(client, data, "in", voltage_attributes,
				     ARRAY_SIZE(voltage_attributes));
	if (ret)
		return ret;

	/* Current sensors */
	ret = pmbus_add_sensor_attrs(client, data, "curr", current_attributes,
				     ARRAY_SIZE(current_attributes));
	if (ret)
		return ret;

	/* Power sensors */
	ret = pmbus_add_sensor_attrs(client, data, "power", power_attributes,
				     ARRAY_SIZE(power_attributes));
	if (ret)
		return ret;

	/* Temperature sensors */
	ret = pmbus_add_sensor_attrs(client, data, "temp", temp_attributes,
				     ARRAY_SIZE(temp_attributes));
	if (ret)
		return ret;

	/* Fans */
	ret = pmbus_add_fan_attributes(client, data);
	return ret;
}

/*
 * Identify chip parameters.
 * This function is called for all chips.
 */
static int pmbus_identify_common(struct i2c_client *client,
				 struct pmbus_data *data)
{
	int vout_mode = -1;

	if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE))
		vout_mode = _pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
	if (vout_mode >= 0 && vout_mode != 0xff) {
		/*
		 * Not all chips support the VOUT_MODE command,
		 * so a failure to read it is not an error.
		 */
		switch (vout_mode >> 5) {
		case 0:	/* linear mode      */
			if (data->info->format[PSC_VOLTAGE_OUT] != linear)
				return -ENODEV;

			data->exponent = ((s8)(vout_mode << 3)) >> 3;
			break;
		case 1: /* VID mode         */
			if (data->info->format[PSC_VOLTAGE_OUT] != vid)
				return -ENODEV;
			break;
		case 2:	/* direct mode      */
			if (data->info->format[PSC_VOLTAGE_OUT] != direct)
				return -ENODEV;
			break;
		default:
			return -ENODEV;
		}
	}

	pmbus_clear_fault_page(client, 0);
	return 0;
}

static int pmbus_init_common(struct i2c_client *client, struct pmbus_data *data,
			     struct pmbus_driver_info *info)
{
	struct device *dev = &client->dev;
	int ret;

	/*
	 * Some PMBus chips don't support PMBUS_STATUS_BYTE, so try
	 * to use PMBUS_STATUS_WORD instead if that is the case.
	 * Bail out if both registers are not supported.
	 */
	data->status_register = PMBUS_STATUS_BYTE;
	ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE);
	if (ret < 0 || ret == 0xff) {
		data->status_register = PMBUS_STATUS_WORD;
		ret = i2c_smbus_read_word_data(client, PMBUS_STATUS_WORD);
		if (ret < 0 || ret == 0xffff) {
			dev_err(dev, "PMBus status register not found\n");
			return -ENODEV;
		}
	}

	pmbus_clear_faults(client);

	if (info->identify) {
		ret = (*info->identify)(client, info);
		if (ret < 0) {
			dev_err(dev, "Chip identification failed\n");
			return ret;
		}
	}

	if (info->pages <= 0 || info->pages > PMBUS_PAGES) {
		dev_err(dev, "Bad number of PMBus pages: %d\n", info->pages);
		return -ENODEV;
	}

	ret = pmbus_identify_common(client, data);
	if (ret < 0) {
		dev_err(dev, "Failed to identify chip capabilities\n");
		return ret;
	}
	return 0;
}

int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id,
		   struct pmbus_driver_info *info)
{
	struct device *dev = &client->dev;
	const struct pmbus_platform_data *pdata = dev->platform_data;
	struct pmbus_data *data;
	int ret;

	if (!info)
		return -ENODEV;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE
				     | I2C_FUNC_SMBUS_BYTE_DATA
				     | I2C_FUNC_SMBUS_WORD_DATA))
		return -ENODEV;

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	i2c_set_clientdata(client, data);
	mutex_init(&data->update_lock);
	data->dev = dev;

	if (pdata)
		data->flags = pdata->flags;
	data->info = info;

	ret = pmbus_init_common(client, data, info);
	if (ret < 0)
		return ret;

	ret = pmbus_find_attributes(client, data);
	if (ret)
		goto out_kfree;

	/*
	 * If there are no attributes, something is wrong.
	 * Bail out instead of trying to register nothing.
	 */
	if (!data->num_attributes) {
		dev_err(dev, "No attributes found\n");
		ret = -ENODEV;
		goto out_kfree;
	}

	/* Register sysfs hooks */
	ret = sysfs_create_group(&dev->kobj, &data->group);
	if (ret) {
		dev_err(dev, "Failed to create sysfs entries\n");
		goto out_kfree;
	}
	data->hwmon_dev = hwmon_device_register(dev);
	if (IS_ERR(data->hwmon_dev)) {
		ret = PTR_ERR(data->hwmon_dev);
		dev_err(dev, "Failed to register hwmon device\n");
		goto out_hwmon_device_register;
	}
	return 0;

out_hwmon_device_register:
	sysfs_remove_group(&dev->kobj, &data->group);
out_kfree:
	kfree(data->group.attrs);
	return ret;
}
EXPORT_SYMBOL_GPL(pmbus_do_probe);

int pmbus_do_remove(struct i2c_client *client)
{
	struct pmbus_data *data = i2c_get_clientdata(client);
	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&client->dev.kobj, &data->group);
	kfree(data->group.attrs);
	return 0;
}
EXPORT_SYMBOL_GPL(pmbus_do_remove);

MODULE_AUTHOR("Guenter Roeck");
MODULE_DESCRIPTION("PMBus core driver");
MODULE_LICENSE("GPL");