summaryrefslogtreecommitdiff
path: root/sys/dev/i2c/i2c_scan.c
blob: 04880775386e5e9529d0bae41d864c00e6b277d3 (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
/*	$OpenBSD: i2c_scan.c,v 1.111 2007/10/30 07:10:34 deraadt Exp $	*/

/*
 * Copyright (c) 2005 Theo de Raadt <deraadt@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * I2C bus scanning.
 */

#include "ipmi.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>

#define _I2C_PRIVATE
#include <dev/i2c/i2cvar.h>

#undef I2C_DEBUG
#define I2C_VERBOSE

#define MAX_IGNORE 8
u_int8_t ignore_addrs[MAX_IGNORE];

struct iicprobelist {
	u_int8_t start, end;
};

/*
 * Addresses at which to probe for sensors.  Skip address 0x4f, since
 * probing it seems to crash at least one Sony VAIO laptop.  Only a
 * few chips can actually sit at that address, and vendors seem to
 * place those at other addresses, so this isn't a big loss.
 */
struct iicprobelist probe_addrs_sensor[] = {
	{ 0x18, 0x1f },
	{ 0x20, 0x2f },
	{ 0x48, 0x4e },
	{ 0, 0 }
};

/*
 * Addresses at which to probe for eeprom devices.
 */
struct iicprobelist probe_addrs_eeprom[] = {
	{ 0x50, 0x57 },
	{ 0, 0 }
};

char 	*iic_probe_sensor(struct device *, u_int8_t);
char	*iic_probe_eeprom(struct device *, u_int8_t);

#define PFLAG_SENSOR	1
static struct {
	struct iicprobelist *pl;
	char	*(*probe)(struct device *, u_int8_t);
	int	flags;
} probes[] = {
	{ probe_addrs_sensor, iic_probe_sensor, PFLAG_SENSOR },
	{ probe_addrs_eeprom, iic_probe_eeprom, 0 },
	{ NULL, NULL }
};

/*
 * Some Maxim 1617 clones MAY NOT even read cmd 0xfc!  When it is
 * read, they will power-on-reset.  Their default condition
 * (control register bit 0x80) therefore will be that they assert
 * /ALERT for the 5 potential errors that may occur.  One of those
 * errors is that the external temperature diode is missing.  This
 * is unfortunately a common choice of system designers, except
 * suddenly now we get a /ALERT, which may on some chipsets cause
 * us to receive an entirely unexpected SMI .. and then an NMI.
 *
 * As we probe each device, if we hit something which looks suspiciously
 * like it may potentially be a 1617 or clone, we immediately set this
 * variable to avoid reading that register offset.
 */
int	skip_fc;

static i2c_tag_t probe_ic;
static u_int8_t probe_addr;
static u_int8_t probe_val[256];

void		iicprobeinit(struct i2cbus_attach_args *, u_int8_t);
u_int8_t	iicprobenc(u_int8_t);
u_int8_t	iicprobe(u_int8_t);
u_int16_t	iicprobew(u_int8_t);
char		*lm75probe(void);
char		*adm1032cloneprobe(u_int8_t);
void		iic_dump(struct device *, u_int8_t, char *);

void
iicprobeinit(struct i2cbus_attach_args *iba, u_int8_t addr)
{
	probe_ic = iba->iba_tag;
	probe_addr = addr;
	memset(probe_val, 0xff, sizeof probe_val);
}

u_int8_t
iicprobenc(u_int8_t cmd)
{
	u_int8_t data;

	/*
	 * If we think we are talking to an evil Maxim 1617 or clone,
	 * avoid accessing this register because it is death.
	 */
	if (skip_fc && cmd == 0xfc)
		return (0xff);
	iic_acquire_bus(probe_ic, 0);
	if (iic_exec(probe_ic, I2C_OP_READ_WITH_STOP,
	    probe_addr, &cmd, 1, &data, 1, 0) != 0)
		data = 0xff;
	iic_release_bus(probe_ic, 0);
	return (data);
}

u_int16_t
iicprobew(u_int8_t cmd)
{
	u_int8_t data[2];

	/*
	 * If we think we are talking to an evil Maxim 1617 or clone,
	 * avoid accessing this register because it is death.
	 */
	if (skip_fc && cmd == 0xfc)
		return (0xffff);
	iic_acquire_bus(probe_ic, 0);
	if (iic_exec(probe_ic, I2C_OP_READ_WITH_STOP,
	    probe_addr, &cmd, 1, &data, 2, 0) != 0)
		data[0] = data[1] = 0xff;
	iic_release_bus(probe_ic, 0);
	return ((data[0] << 8) | data[1]);
}

u_int8_t
iicprobe(u_int8_t cmd)
{
	if (probe_val[cmd] != 0xff)
		return probe_val[cmd];
	probe_val[cmd] = iicprobenc(cmd);
	return (probe_val[cmd]);
}

#define LM75TEMP	0x00
#define LM75CONF	0x01
#define LM75Thyst	0x02
#define LM75Tos		0x03
#define LM77Tlow	0x04
#define LM77Thigh	0x05
#define LM75TMASK	0xff80	/* 9 bits in temperature registers */
#define LM77TMASK	0xfff8	/* 13 bits in temperature registers */

/*
 * The LM75/LM75A/LM77 family are very hard to detect.  Thus, we check
 * for all other possible chips first.  These chips do not have an
 * ID register.  They do have a few quirks though:
 * -  on the LM75 and LM77, registers 0x06 and 0x07 return whatever
 *    value was read before
 * -  the LM75 lacks registers 0x04 and 0x05, so those act as above
 * -  the LM75A returns 0xffff for registers 0x04, 0x05, 0x06 and 0x07
 * -  the chip registers loop every 8 registers
 * The downside is that we must read almost every register to guess
 * if this is an LM75, LM75A or LM77.
 */
char *
lm75probe(void)
{
	u_int16_t temp, thyst, tos, tlow, thigh, mask = LM75TMASK;
	u_int8_t conf;
	int i, echocount, ffffcount, score;
	int echoreg67, echoreg45, ffffreg67, ffffreg45;

	temp = iicprobew(LM75TEMP);

	/*
	 * Sometimes the other probes can upset the chip, if we get 0xffff
	 * the first time, try it once more.
	 */
	if (temp == 0xffff)
		temp = iicprobew(LM75TEMP);

	conf = iicprobenc(LM75CONF);
	thyst = iicprobew(LM75Thyst);
	tos = iicprobew(LM75Tos);

	/* totally bogus data */
	if (conf == 0xff && temp == 0xffff && thyst == 0xffff)
		return (NULL);

	temp &= mask;
	thyst &= mask;
	tos &= mask;

	/* All values the same?  Very unlikely */
	if (temp == thyst && thyst == tos)
		return (NULL);

#if notsure
	/* more register aliasing effects that indicate not a lm75 */
	if ((temp >> 8) == conf)
		return (NULL);
#endif

	/*
	 * LM77/LM75 registers 6, 7
	 * echo whatever was read just before them from reg 0, 1, or 2
	 *
	 * LM75A doesn't appear to do this, but does appear to reliably
	 * return 0xffff
	 */
	for (i = 6, echocount = 2, ffffcount = 0; i <= 7; i++) {
		if ((iicprobew(LM75TEMP) & mask) != (iicprobew(i) & mask) ||
		    (iicprobew(LM75Thyst) & mask) != (iicprobew(i) & mask) ||
		    (iicprobew(LM75Tos) & mask) != (iicprobew(i) & mask))
			echocount--;
		if (iicprobew(i) == 0xffff)
			ffffcount++;
	}

	/* Make sure either both registers echo, or neither does */
	if (echocount == 1 || ffffcount == 1)
		return (NULL);

	echoreg67 = (echocount == 0) ? 0 : 1;
	ffffreg67 = (ffffcount == 0) ? 0 : 1;

	/*
	 * LM75 has no registers 4 or 5, and they will act as echos too
	 *
	 * LM75A doesn't appear to do this either, but does appear to
	 * reliably return 0xffff
	 */
	for (i = 4, echocount = 2, ffffcount = 0; i <= 5; i++) {
		if ((iicprobew(LM75TEMP) & mask) != (iicprobew(i) & mask) ||
		    (iicprobew(LM75Thyst) & mask) != (iicprobew(i) & mask) ||
		    (iicprobew(LM75Tos) & mask) != (iicprobew(i) & mask))
			echocount--;
		if (iicprobew(i) == 0xffff)
			ffffcount++;
	}

	/* Make sure either both registers echo, or neither does */
	if (echocount == 1 || ffffcount == 1)
		return (NULL);

	echoreg45 = (echocount == 0) ? 0 : 1;
	ffffreg45 = (ffffcount == 0) ? 0 : 1;

	/*
	 * If we find that 4 and 5 are not echos, and don't return 0xffff
	 * then based on whether the echo test of registers 6 and 7
	 * succeeded or not, we may have an LM77
	 */
	if (echoreg45 == 0 && ffffreg45 == 0 && echoreg67 == 1) {
		mask = LM77TMASK;

		/* mask size changed, must re-read for the next checks */
		thyst = iicprobew(LM75Thyst) & mask;
		tos = iicprobew(LM75Tos) & mask;
		tlow = iicprobew(LM77Tlow) & mask;
		thigh = iicprobew(LM77Thigh) & mask;
	}

	/* a real LM75/LM75A/LM77 repeats its registers.... */
	for (i = 0x08; i <= 0xf8; i += 8) {
		if (conf != iicprobenc(LM75CONF + i) ||
		    thyst != (iicprobew(LM75Thyst + i) & mask) ||
		    tos != (iicprobew(LM75Tos + i) & mask))
			return (NULL);

		/*
		 * Check that the repeated registers 0x06 and 0x07 still
		 * either echo or return 0xffff
		 */
		if (echoreg67 == 1) {
			tos = iicprobew(LM75Tos) & mask;
			if (tos != (iicprobew(0x06 + i) & mask) ||
			    tos != (iicprobew(0x07 + i) & mask))
				return (NULL);
		} else if (ffffreg67 == 1)
			if (iicprobew(0x06 + i) != 0xffff ||
			    iicprobew(0x07 + i) != 0xffff)
				return (NULL);

		/*
		 * Check that the repeated registers 0x04 and 0x05 still
		 * either echo or return 0xffff. If they do neither, and
		 * registers 0x06 and 0x07 echo, then we will be probing
		 * for an LM77, so make sure those still repeat
		 */
		if (echoreg45 == 1) {
			tos = iicprobew(LM75Tos) & mask;
			if (tos != (iicprobew(LM77Tlow + i) & mask) ||
			    tos != (iicprobew(LM77Thigh + i) & mask))
				return (NULL);
		} else if (ffffreg45 == 1) {
			if (iicprobew(LM77Tlow + i) != 0xffff ||
			    iicprobew(LM77Thigh + i) != 0xffff)
				return (NULL);
		} else if (echoreg67 == 1)
			if (tlow != (iicprobew(LM77Tlow + i) & mask) ||
			    thigh != (iicprobew(LM77Thigh + i) & mask))
				return (NULL);
	}

	/*
	 * Given that we now know how the first eight registers behave and
	 * that this behaviour is consistently repeated, we can now use
	 * the following table:
	 *
	 * echoreg67 | echoreg45 | ffffreg67 | ffffreg45 | chip
	 * ----------+-----------+-----------+-----------+------
	 *     1     |     1     |     0     |     0     | LM75
	 *     1     |     0     |     0     |     0     | LM77
	 *     0     |     0     |     1     |     1     | LM75A
	 */

	/* Convert the various flags into a single score */
	score = (echoreg67 << 3) + (echoreg45 << 2) + (ffffreg67 << 1) +
	    ffffreg45;

	switch (score) {
	case 12:
		return ("lm75");
	case 8:
		return ("lm77");
	case 3:
		return ("lm75a");
	default:
#if defined(I2C_DEBUG)
		printf("lm75probe: unknown chip, scored %d\n", score);
#endif /* defined(I2C_DEBUG) */
		return (NULL);
	}
}

char *
adm1032cloneprobe(u_int8_t addr)
{
	if (addr == 0x18 || addr == 0x1a || addr == 0x29 ||
	    addr == 0x2b || addr == 0x4c || addr == 0x4e) {
		u_int8_t reg, val;
		int zero = 0, copy = 0;

		val = iicprobe(0x00);
		for (reg = 0x00; reg < 0x09; reg++) {
			if (iicprobe(reg) == 0xff)
				return (NULL);
			if (iicprobe(reg) == 0x00)
				zero++;
			if (val == iicprobe(reg))
				copy++;
		}
		if (zero > 6 || copy > 6)
			return (NULL);
		val = iicprobe(0x09);
		for (reg = 0x0a; reg < 0xfc; reg++) {
			if (iicprobe(reg) != val)
				return (NULL);
		}
		/* 0xfe may be Maxim, or some other vendor */
		if (iicprobe(0xfe) == 0x4d)
			return ("max1617");
		/*
		 * "xeontemp" is the name we choose for clone chips
		 * which have all sorts of buggy bus interactions, such
		 * as those we just probed.  Why?
		 * Intel is partly to blame for this situation.
		 */
		return ("xeontemp");
	}
	return (NULL);
}

void
iic_ignore_addr(u_int8_t addr)
{
	int i;

	for (i = 0; i < sizeof(ignore_addrs); i++)
		if (ignore_addrs[i] == 0) {
			ignore_addrs[i] = addr;
			return;
		}
}

#ifdef I2C_VERBOSE
void
iic_dump(struct device *dv, u_int8_t addr, char *name)
{
	static u_int8_t iicvalcnt[256];
	u_int8_t val, val2, max;
	int i, cnt = 0;

	/*
	 * Don't bother printing the most often repeated register
	 * value, since it is often weird devices that respond
	 * incorrectly, busted controller driver, or in the worst
	 * case, it in mosts cases, the value 0xff.
	 */
	bzero(iicvalcnt, sizeof iicvalcnt);
	val = iicprobe(0);
	iicvalcnt[val]++;
	for (i = 1; i <= 0xff; i++) {
		val2 = iicprobe(i);
		iicvalcnt[val2]++;
		if (val == val2)
			cnt++;
	}

	for (val = max = i = 0; i <= 0xff; i++)
		if (max < iicvalcnt[i]) {
			max = iicvalcnt[i];
			val = i;
		}

	if (cnt == 255)
		return;

	printf("%s: addr 0x%x", dv->dv_xname, addr);
	for (i = 0; i <= 0xff; i++) {
		if (iicprobe(i) != val)
			printf(" %02x=%02x", i, iicprobe(i));
	}
	printf(" words", dv->dv_xname, addr);
	for (i = 0; i < 16; i++)
		printf(" %02x=%04x", i, iicprobew(i));
	if (name)
		printf(": %s", name);
	printf("\n");
}
#endif /* I2C_VERBOSE */

char *
iic_probe_sensor(struct device *self, u_int8_t addr)
{
	char *name = NULL;

	skip_fc = 0;

	/*
	 * Many I2C/SMBus devices use register 0x3e as a vendor ID
	 * register.
	 */
	switch (iicprobe(0x3e)) {
	case 0x01:		/* National Semiconductor */
		/*
		 * Some newer National products use a vendor code at
		 * 0x3e of 0x01, and then 0x3f contains a product code
		 * But some older products are missing a product code,
		 * and contain who knows what in that register.  We assume
		 * that some employee was smart enough to keep the numbers
		 * unique.
		 */
		if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    (iicprobe(0x3f) == 0x73 || iicprobe(0x3f) == 0x72) &&
		    iicprobe(0x00) == 0x00)
			name = "lm93";	/* product 0x72 is the prototype */
		else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    iicprobe(0x3f) == 0x68)
			name = "lm96000";	/* adt7460 compat? */
		else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    (iicprobe(0x3f) == 0x60 || iicprobe(0x3f) == 0x62))
			name = "lm85";		/* lm85C/B == adt7460 compat */
		else if ((addr & 0x7c) == 0x2c &&	/* addr 0b01011xx */
		    iicprobe(0x48) == addr &&
		    (iicprobe(0x3f) == 0x03 || iicprobe(0x3f) == 0x04) &&
		    (iicprobe(0x40) & 0x80) == 0x00)
			name = "lm81";
		break;
	case 0x02:		/* National Semiconductor? */
		if ((iicprobe(0x3f) & 0xfc) == 0x04)
			name = "lm87";		/* complete check */
		break;
	case 0x23:		/* Analog Devices? */
		if (iicprobe(0x48) == addr &&
		    (iicprobe(0x40) & 0x80) == 0x00 &&
		    (addr & 0x7c) == 0x2c)
			name = "adm9240";	/* lm87 clone */
		break;
	case 0x41:		/* Analog Devices */
		/*
		 * Newer chips have a valid 0x3d product number, while
		 * older ones sometimes encoded the product into the
		 * upper half of the "step register" at 0x3f.
		 */
		if ((addr == 0x2c || addr == 0x2e || addr == 0x2f) &&
		    iicprobe(0x3d) == 0x70)
			name = "adt7470";
		else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    iicprobe(0x3d) == 0x76)
			name = "adt7476"; /* or adt7476a */
		else if (addr == 0x2e && iicprobe(0x3d) == 0x75)
			name = "adt7475";
		else if (iicprobe(0x3d) == 0x27 &&
		    (iicprobe(0x3f) == 0x60 || iicprobe(0x3f) == 0x6a))
			name = "adm1027";	/* complete check */
		else if (iicprobe(0x3d) == 0x27 &&
		    (iicprobe(0x3f) == 0x62 || iicprobe(0x3f) == 0x6a))
			name = "adt7460";	/* complete check */
		else if ((addr == 0x2c || addr == 0x2e) &&
		    iicprobe(0x3d) == 0x62 && iicprobe(0x3f) == 0x04)
			name = "adt7462";
		else if (addr == 0x2e &&
		    iicprobe(0x3d) == 0x68 && (iicprobe(0x3f) & 0xf0) == 0x70)
			name = "adt7467"; /* or adt7468 */
		else if (iicprobe(0x3d) == 0x33)
			name = "adm1033";
                else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    iicprobe(0x3d) == 0x30 &&
		    (iicprobe(0x01) & 0x80) == 0x00 &&
		    (iicprobe(0x0d) & 0x70) == 0x00 &&
		    (iicprobe(0x0e) & 0x70) == 0x00)
			/*
			 * Revision 3 seems to be an adm1031 with
			 * remote diode 2 shorted.  Therefore we
			 * cannot assume the reserved/unused bits of
			 * register 0x03 and 0x06 are set to zero.
			 */
			name = "adm1030";       /* complete check */
                else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    iicprobe(0x3d) == 0x31 &&
		    (iicprobe(0x01) & 0x80) == 0x00 &&
		    (iicprobe(0x0d) & 0x70) == 0x00 &&
		    (iicprobe(0x0e) & 0x70) == 0x00 &&
		    (iicprobe(0x0f) & 0x70) == 0x00)
			name = "adm1031";	/* complete check */
		else if ((addr & 0x7c) == 0x2c &&	/* addr 0b01011xx */
		    (iicprobe(0x3f) & 0xf0) == 0x20 &&
		    (iicprobe(0x40) & 0x80) == 0x00 &&
		    (iicprobe(0x41) & 0xc0) == 0x00 &&
		    (iicprobe(0x42) & 0xbc) == 0x00)
			name = "adm1025";	/* complete check */
		else if ((addr & 0x7c) == 0x2c &&	/* addr 0b01011xx */
		    (iicprobe(0x3f) & 0xf0) == 0x10 &&
		    (iicprobe(0x40) & 0x80) == 0x00)
			name = "adm1024";	/* complete check */
		else if ((iicprobe(0xff) & 0xf0) == 0x30)
			name = "adm1023";
		else if (addr == 0x2e &&
		    (iicprobe(0x3f) & 0xf0) == 0xd0 &&
		    (iicprobe(0x40) & 0x80) == 0x00)
			name = "adm1028";	/* adm1022 clone? */
		else if ((addr == 0x2c || addr == 0x2e || addr == 0x2f) &&
		    (iicprobe(0x3f) & 0xf0) == 0xc0 &&
		    (iicprobe(0x40) & 0x80) == 0x00)
			name = "adm1022";
		break;
	case 0x49:		/* Texas Instruments */
		if ((addr == 0x2c || addr == 0x2e || addr == 0x2f) &&
		    (iicprobe(0x3f) & 0xf0) == 0xc0 &&
		    (iicprobe(0x40) & 0x80) == 0x00)
			name = "thmc50";	/* adm1022 clone */
		break;
	case 0x55:		/* SMSC */
		if ((addr & 0x7c) == 0x2c &&		/* addr 0b01011xx */
		    iicprobe(0x3f) == 0x20 &&
		    (iicprobe(0x47) & 0x70) == 0x00 &&
		    (iicprobe(0x49) & 0xfe) == 0x80)
			name = "47m192";	/* adm1025 compat */
		break;
	case 0x5c:		/* SMSC */
		if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    (iicprobe(0x3f) & 0xf0) == 0x60)
			name = "emc6d100";   /* emc6d101, emc6d102, emc6d103 */
		else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    (iicprobe(0x3f) & 0xf0) == 0x80)
			name = "sch5017";
		else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    (iicprobe(0x3f) & 0xf0) == 0xb0)
			name = "emc6w201";
		break;
	case 0x61:		/* Andigilog */
		if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
		    iicprobe(0x3f) == 0x6c)
			name = "asc7621";
		break;
	case 0xa1:		/* Philips */
		if ((iicprobe(0x3f) & 0xf0) == 0x20 &&
		    (iicprobe(0x40) & 0x80) == 0x00 &&
		    (iicprobe(0x41) & 0xc0) == 0x00 &&
		    (iicprobe(0x42) & 0xbc) == 0x00)
			name = "ne1619";	/* adm1025 compat */
		break;
	case 0xda:		/* Dallas Semiconductor */
		if (iicprobe(0x3f) == 0x01 && iicprobe(0x48) == addr &&
		    (iicprobe(0x40) & 0x80) == 0x00)
			name = "ds1780";	/* lm87 clones */
		break;
	}

	switch (iicprobe(0x4e)) {
	case 0x41:		/* Analog Devices */
		if ((addr == 0x48 || addr == 0x4a || addr == 0x4b) &&
		    (iicprobe(0x4d) == 0x03 || iicprobe(0x4d) == 0x08 ||
		    iicprobe(0x4d) == 0x07))
			name = "adt7516";	/* adt7517, adt7519 */
		break;
	}

	switch (iicprobe(0xfe)) {
	case 0x01:		/* National Semiconductor */
		if (addr == 0x4c &&
		    iicprobe(0xff) == 0x41 && (iicprobe(0x03) & 0x18) == 0 &&
		    iicprobe(0x04) <= 0x0f && (iicprobe(0xbf) & 0xf8) == 0)
			name = "lm63";
		else if (addr == 0x4c &&
		    iicprobe(0xff) == 0x11 && (iicprobe(0x03) & 0x2a) == 0 &&
		    iicprobe(0x04) <= 0x09 && (iicprobe(0xbf) & 0xf8) == 0)
			name = "lm86";
		else if (addr == 0x4c &&
		    iicprobe(0xff) == 0x31 && (iicprobe(0x03) & 0x2a) == 0 &&
		    iicprobe(0x04) <= 0x09 && (iicprobe(0xbf) & 0xf8) == 0)
			name = "lm89";		/* or lm99 */
		else if (addr == 0x4d &&
		    iicprobe(0xff) == 0x34 && (iicprobe(0x03) & 0x2a) == 0 &&
		    iicprobe(0x04) <= 0x09 && (iicprobe(0xbf) & 0xf8) == 0)
			name = "lm89-1";	/* or lm99-1 */
		else if (addr == 0x4c &&
		    iicprobe(0xff) == 0x21 && (iicprobe(0x03) & 0x2a) == 0 &&
		    iicprobe(0x04) <= 0x09 && (iicprobe(0xbf) & 0xf8) == 0)
			name = "lm90";
		break;
	case 0x23:		/* Genesys Logic? */
		if ((addr == 0x4c) &&
		    (iicprobe(0x03) & 0x3f) == 0x00 && iicprobe(0x04) <= 0x08)
			/*
			 * Genesys Logic doesn't make the datasheet
			 * for the GL523SM publically available, so
			 * the checks above are nothing more than a
			 * (conservative) educated guess.
			 */
			name = "gl523sm";
		break;
	case 0x41:		/* Analog Devices */
		if ((addr == 0x4c || addr == 0x4d) &&
		    iicprobe(0xff) == 0x51 &&
		    (iicprobe(0x03) & 0x1f) == 0x04 &&
		    iicprobe(0x04) <= 0x0a) {
			/* If not in adm1032 compatibility mode. */
			name = "adt7461";
		} else if ((addr == 0x18 || addr == 0x19 || addr == 0x1a ||
		    addr == 0x29 || addr == 0x2a || addr == 0x2b ||
		    addr == 0x4c || addr == 0x4d || addr == 0x4e) &&
		    (iicprobe(0xff) & 0xf0) == 0x00 &&
		    (iicprobe(0x03) & 0x3f) == 0x00 &&
		    iicprobe(0x04) <= 0x07) {
			name = "adm1021";
			skip_fc = 1;
		} else if ((addr == 0x18 || addr == 0x19 || addr == 0x1a ||
		    addr == 0x29 || addr == 0x2a || addr == 0x2b ||
		    addr == 0x4c || addr == 0x4d || addr == 0x4e) &&
		    (iicprobe(0xff) & 0xf0) == 0x30 &&
		    (iicprobe(0x03) & 0x3f) == 0x00 &&
		    iicprobe(0x04) <= 0x07) {
			name = "adm1023";	/* or adm1021a */
			skip_fc = 1;
		} else if ((addr == 0x4c || addr == 0x4d || addr == 0x4e) &&
		    (iicprobe(0x03) & 0x3f) == 0x00 &&
		    iicprobe(0x04) <= 0x0a) {
			name = "adm1032";	/* or adm1020 */
			skip_fc = 1;
		}
		break;
	case 0x47:		/* Global Mixed-mode Technology */
		if (addr == 0x4c && iicprobe(0xff) == 0x01 &&
		    (iicprobe(0x03) & 0x3f) == 0x00 && iicprobe(0x04) <= 0x08)
			name = "g781";
		if (addr == 0x4d && iicprobe(0xff) == 0x03 &&
		    (iicprobe(0x03) & 0x3f) == 0x00 && iicprobe(0x04) <= 0x08)
			name = "g781-1";
		break;
	case 0x4d:		/* Maxim */
		if ((addr == 0x18 || addr == 0x19 || addr == 0x1a ||
		     addr == 0x29 || addr == 0x2a || addr == 0x2b ||
		     addr == 0x4c || addr == 0x4d || addr == 0x4e) &&
		    iicprobe(0xff) == 0x08 && (iicprobe(0x02) & 0x03) == 0 &&
		    (iicprobe(0x03) & 0x07) == 0 && iicprobe(0x04) <= 0x08)
			name = "max6690";
		else if ((addr == 0x4c || addr == 0x4d || addr == 0x4e) &&
		    iicprobe(0xff) == 0x59 && (iicprobe(0x03) & 0x1f) == 0 &&
		    iicprobe(0x04) <= 0x07)
			name = "max6646";	/* max6647/8/9, max6692 */
		else if ((addr == 0x4c || addr == 0x4d || addr == 0x4e) &&
		    (iicprobe(0x02) & 0x2b) == 0 &&
		    (iicprobe(0x03) & 0x0f) == 0 && iicprobe(0x04) <= 0x09) {
			name = "max6657";	/* max6658, max6659 */
			skip_fc = 1;
		} else if ((addr >= 0x48 && addr <= 0x4f) &&
		    (iicprobe(0x02) & 0x2b) == 0 &&
		    (iicprobe(0x03) & 0x0f) == 0)
			name = "max6642";
		break;
	case 0x55:		/* Texas Instruments */
		if (addr == 0x4c && iicprobe(0xff) == 0x11 &&
		    (iicprobe(0x03) & 0x1b) == 0x00 &&
		    (iicprobe(0x04) & 0xf0) == 0x00 &&
		    (iicprobe(0x10) & 0x0f) == 0x00 &&
		    (iicprobe(0x13) & 0x0f) == 0x00 &&
		    (iicprobe(0x14) & 0x0f) == 0x00 &&
		    (iicprobe(0x15) & 0x0f) == 0x00 &&
		    (iicprobe(0x16) & 0x0f) == 0x00 &&
		    (iicprobe(0x17) & 0x0f) == 0x00)
			name = "tmp401";
		break;
	}

	if (addr == iicprobe(0x48) &&
	    ((iicprobe(0x4f) == 0x5c && (iicprobe(0x4e) & 0x80)) ||
	    (iicprobe(0x4f) == 0xa3 && !(iicprobe(0x4e) & 0x80)))) {
		/*
		 * We could toggle 0x4e bit 0x80, then re-read 0x4f to
		 * see if the value changes to 0xa3 (indicating Winbond).
		 * But we are trying to avoid writes.
		 */
		if ((iicprobe(0x4e) & 0x07) == 0) {
			switch (iicprobe(0x58)) {
			case 0x10:
			case 0x11:			/* rev 2? */
				name = "w83781d";
				break;
			case 0x21:
				name = "w83627hf";
				break;
			case 0x30:
				name = "w83782d";
				break;
			case 0x31:
				name = "as99127f";	/* rev 2 */
				break;
			case 0x40:
				name = "w83783s";
				break;
			case 0x71:
				name = "w83791d";
				break;
			case 0x72:
				name = "w83791sd";
				break;
			case 0x7a:
				name = "w83792d";
				break;
			}
		} else {
			/*
			 * The BIOS left the chip in a non-zero
			 * register bank.  Assume it's a W83781D and
			 * let lm(4) sort out the real model.
			 */
			name = "w83781d";
		}
	} else if (addr == iicprobe(0x4a) && iicprobe(0x4e) == 0x50 &&
	    iicprobe(0x4c) == 0xa3 && iicprobe(0x4d) == 0x5c) {
		name = "w83l784r";
	} else if (addr == 0x2d && iicprobe(0x4e) == 0x60 &&
	    iicprobe(0x4c) == 0xa3 && iicprobe(0x4d) == 0x5c) {
		name = "w83l785r";
	} else if (addr == 0x2e && iicprobe(0x4e) == 0x70 &&
	    iicprobe(0x4c) == 0xa3 && iicprobe(0x4d) == 0x5c) {
		name = "w83l785ts-l";
	} else if (addr >= 0x2c && addr <= 0x2f &&
	    addr * 2 == iicprobe(0x0b) &&
	    (iicprobe(0x0c) & 0x40) && !(iicprobe(0x0c) & 0x04) &&
	    iicprobe(0x0e) == 0x7b &&
	    (iicprobe(0x0f) == 0x11 || iicprobe(0x0f) == 0x12) &&
	    ((iicprobe(0x0d) == 0x5c && (iicprobe(0x00) & 0x80)) ||
	    (iicprobe(0x0d) == 0xa3 && !(iicprobe(0x00) & 0x80)))) {
		name = "w83793g";
	} else if (addr >= 0x28 && addr <= 0x2f &&
	    iicprobe(0x4f) == 0x12 && (iicprobe(0x4e) & 0x80)) {
		/*
		 * We could toggle 0x4e bit 0x80, then re-read 0x4f to
		 * see if the value changes to 0xc3 (indicating ASUS).
		 * But we are trying to avoid writes.
		 */
		if (iicprobe(0x58) == 0x31)
			name = "as99127f";	/* rev 1 */
	} else if ((addr == 0x2d || addr == 0x2e) &&
	    addr * 2 == iicprobe(0x04) &&
	    iicprobe(0x5d) == 0x19 && iicprobe(0x5e) == 0x34 &&
	    iicprobe(0x5a) == 0x03 && iicprobe(0x5b) == 0x06) {
		name = "f75375";	/* Fintek */
	} else if (addr == 0x2d &&
	    ((iicprobe(0x4f) == 0x06 && (iicprobe(0x4e) & 0x80)) ||
	    (iicprobe(0x4f) == 0x94 && !(iicprobe(0x4e) & 0x80)))) {
		/*
		 * We could toggle 0x4e bit 0x80, then re-read 0x4f to
		 * see if the value changes to 0x94 (indicating ASUS).
		 * But we are trying to avoid writes.
		 *
		 * NB. we won't match if the BIOS has selected a non-zero
		 * register bank (set via 0x4e). We could select bank 0 so
		 * we see the right registers, but that would require a
		 * write.  In general though, we bet no BIOS would leave us
		 * in the wrong state.
		 */
		if ((iicprobe(0x58) & 0x7f) == 0x31 &&
		    (iicprobe(0x4e) & 0xf) == 0x00)
			name = "asb100";
	} else if ((addr == 0x2c || addr == 0x2d) &&
	    iicprobe(0x00) == 0x80 &&
	    (iicprobe(0x01) == 0x00 || iicprobe(0x01) == 0x80) &&
	    iicprobe(0x02) == 0x00 && (iicprobe(0x03) & 0x83) == 0x00 &&
	    (iicprobe(0x0f) & 0x07) == 0x00 &&
	    (iicprobe(0x11) & 0x80) == 0x00 &&
	    (iicprobe(0x12) & 0x80) == 0x00) {
		/*
		 * The GL518SM is really crappy.  It has both byte and
		 * word registers, and reading a word register with a
		 * byte read command will make the device crap out and
		 * hang the bus.  This has nasty consequences on some
		 * machines, like preventing warm reboots.  The word
		 * registers are 0x07 through 0x0c, so make sure the
		 * checks above don't access those registers.  We
		 * don't want to do this check right up front though
		 * since this chip is somewhat hard to detect (which
		 * is why we check for every single fixed bit it has).
		 */
		name = "gl518sm";
	} else if ((addr == 0x2c || addr == 0x2d || addr == 0x2e) &&
	      iicprobe(0x16) == 0x41 && ((iicprobe(0x17) & 0xf0) == 0x40)) {
		name = "adm1026";
	} else if (name == NULL &&
	    (addr & 0x78) == 0x48) {		/* addr 0b1001xxx */
		name = lm75probe();
	}
#if 0
	/*
	 * XXX This probe needs to be improved; the driver does some
	 * dangerous writes.
	 */
	if (name == NULL && (addr & 0x7c) == 0x48 &&	/* addr 0b1001xxx */
	    (iicprobew(0xaa) & 0x0007) == 0x0000 &&
	    (iicprobew(0xa1) & 0x0007) == 0x0000 &&
	    (iicprobew(0xa2) & 0x0007) == 0x0000 &&
	    (iicprobe(0xac) & 0x10) == 0x00) {
		if ((iicprobe(0xac) & 0x7e) == 0x0a &&
		    iicprobe(0xab) == 0x00 && iicprobe(0xa8) == 0x00)
			name = "ds1624";
		else if ((iicprobe(0xac) & 0x7e) == 0x0c)
			name = "ds1631";	/* terrible probe */
		else if ((iicprobe(0xac) & 0x2e) == 0x2e)
			name = "ds1721";	/* terrible probe */
	}
#endif
	if (name == NULL && (addr & 0xf8) == 0x28 && iicprobe(0x48) == addr &&
	    (iicprobe(0x00) & 0x90) == 0x10 && iicprobe(0x58) == 0x90) {
		if (iicprobe(0x5b) == 0x12)
			name = "it8712";
		else if (iicprobe(0x5b) == 0x00)
			name = "it8712f-a";		/* sis950 too */
	}

	if (name == NULL && iicprobe(0x48) == addr &&
	    (iicprobe(0x40) & 0x80) == 0x00 && iicprobe(0x58) == 0xac)
		name = "mtp008";

	if (name == NULL) {
		name = adm1032cloneprobe(addr);
		if (name)
			skip_fc = 1;
	}

	return (name);
}

char *
iic_probe_eeprom(struct device *self, u_int8_t addr)
{
	int reg, csum = 0;
	char *name = NULL;

	/* SPD EEPROMs should only set lower nibble for size (ie <= 32K) */
	if ((iicprobe(0x01) & 0xf0) != 0)
		return (name);

	for (reg = 0; reg < 0x3f; reg++)
		csum += iicprobe(reg);

	if (iicprobe(0x3f) == (csum & 0xff))
		name = "spd";
	return (name);
}

void
iic_scan(struct device *self, struct i2cbus_attach_args *iba)
{
	i2c_tag_t ic = iba->iba_tag;
	struct i2c_attach_args ia;
	struct iicprobelist *pl;
	u_int8_t cmd = 0, addr;
	char *name;
	int i, j, k;

	bzero(ignore_addrs, sizeof(ignore_addrs));

	for (i = 0; probes[i].probe; i++) {
#if NIPMI > 0
		extern int ipmi_enabled;

		if ((probes[i].flags & PFLAG_SENSOR) && ipmi_enabled) {
			printf("%s: skipping sensors to avoid ipmi0 interactions\n",
			    self->dv_xname);
			continue;
		}
#endif
		pl = probes[i].pl;
		for (j = 0; pl[j].start && pl[j].end; j++) {
			for (addr = pl[j].start; addr <= pl[j].end; addr++) {
				for (k = 0; k < sizeof(ignore_addrs); k++)
					if (ignore_addrs[k] == addr)
						continue;

				/* Perform RECEIVE BYTE command */
				iic_acquire_bus(ic, 0);
				if (iic_exec(ic, I2C_OP_READ_WITH_STOP, addr,
				    &cmd, 1, NULL, 0, 0) == 0) {
					iic_release_bus(ic, 0);

					/* Some device exists */
					iicprobeinit(iba, addr);
					name = (*probes[i].probe)(self, addr);
#ifndef I2C_VERBOSE
					if (name == NULL)
						name = "unknown";
#endif /* !I2C_VERBOSE */
					if (name) {
						memset(&ia, 0, sizeof(ia));
						ia.ia_tag = iba->iba_tag;
						ia.ia_addr = addr;
						ia.ia_size = 1;
						ia.ia_name = name;
						if (config_found(self,
						    &ia, iic_print))
							continue;
					}
#ifdef I2C_VERBOSE
					if ((probes[i].flags & PFLAG_SENSOR))
						iic_dump(self, addr, name);
#endif /* I2C_VERBOSE */
				} else
					iic_release_bus(ic, 0);
			}
		}
	}
}