summaryrefslogtreecommitdiffstats
path: root/drivers/pnp/isapnp/core.c
blob: 2e5e58c777dd542a7918da00b3289a2e7e7677c4 (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
/*
 *  ISA Plug & Play support
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *
 *   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.
 *
 *  Changelog:
 *  2000-01-01	Added quirks handling for buggy hardware
 *		Peter Denison <peterd@pnd-pc.demon.co.uk>
 *  2000-06-14	Added isapnp_probe_devs() and isapnp_activate_dev()
 *		Christoph Hellwig <hch@infradead.org>
 *  2001-06-03  Added release_region calls to correspond with
 *		request_region calls when a failure occurs.  Also
 *		added KERN_* constants to printk() calls.
 *  2001-11-07  Added isapnp_{,un}register_driver calls along the lines
 *              of the pci driver interface
 *              Kai Germaschewski <kai.germaschewski@gmx.de>
 *  2002-06-06  Made the use of dma channel 0 configurable
 *              Gerald Teschl <gerald.teschl@univie.ac.at>
 *  2002-10-06  Ported to PnP Layer - Adam Belay <ambx1@neo.rr.com>
 *  2003-08-11	Resource Management Updates - Adam Belay <ambx1@neo.rr.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/isapnp.h>
#include <linux/mutex.h>
#include <asm/io.h>

#include "../base.h"

#if 0
#define ISAPNP_REGION_OK
#endif

int isapnp_disable;		/* Disable ISA PnP */
static int isapnp_rdp;		/* Read Data Port */
static int isapnp_reset = 1;	/* reset all PnP cards (deactivate) */
static int isapnp_verbose = 1;	/* verbose mode */

MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
MODULE_DESCRIPTION("Generic ISA Plug & Play support");
module_param(isapnp_disable, int, 0);
MODULE_PARM_DESC(isapnp_disable, "ISA Plug & Play disable");
module_param(isapnp_rdp, int, 0);
MODULE_PARM_DESC(isapnp_rdp, "ISA Plug & Play read data port");
module_param(isapnp_reset, int, 0);
MODULE_PARM_DESC(isapnp_reset, "ISA Plug & Play reset all cards");
module_param(isapnp_verbose, int, 0);
MODULE_PARM_DESC(isapnp_verbose, "ISA Plug & Play verbose mode");
MODULE_LICENSE("GPL");

#define _PIDXR		0x279
#define _PNPWRP		0xa79

/* short tags */
#define _STAG_PNPVERNO		0x01
#define _STAG_LOGDEVID		0x02
#define _STAG_COMPATDEVID	0x03
#define _STAG_IRQ		0x04
#define _STAG_DMA		0x05
#define _STAG_STARTDEP		0x06
#define _STAG_ENDDEP		0x07
#define _STAG_IOPORT		0x08
#define _STAG_FIXEDIO		0x09
#define _STAG_VENDOR		0x0e
#define _STAG_END		0x0f
/* long tags */
#define _LTAG_MEMRANGE		0x81
#define _LTAG_ANSISTR		0x82
#define _LTAG_UNICODESTR	0x83
#define _LTAG_VENDOR		0x84
#define _LTAG_MEM32RANGE	0x85
#define _LTAG_FIXEDMEM32RANGE	0x86

/* Logical device control and configuration registers */

#define ISAPNP_CFG_ACTIVATE	0x30	/* byte */
#define ISAPNP_CFG_MEM		0x40	/* 4 * dword */
#define ISAPNP_CFG_PORT		0x60	/* 8 * word */
#define ISAPNP_CFG_IRQ		0x70	/* 2 * word */
#define ISAPNP_CFG_DMA		0x74	/* 2 * byte */

/*
 * Sizes of ISAPNP logical device configuration register sets.
 * See PNP-ISA-v1.0a.pdf, Appendix A.
 */
#define ISAPNP_MAX_MEM		4
#define ISAPNP_MAX_PORT		8
#define ISAPNP_MAX_IRQ		2
#define ISAPNP_MAX_DMA		2

static unsigned char isapnp_checksum_value;
static DEFINE_MUTEX(isapnp_cfg_mutex);
static int isapnp_csn_count;

/* some prototypes */

static inline void write_data(unsigned char x)
{
	outb(x, _PNPWRP);
}

static inline void write_address(unsigned char x)
{
	outb(x, _PIDXR);
	udelay(20);
}

static inline unsigned char read_data(void)
{
	unsigned char val = inb(isapnp_rdp);
	return val;
}

unsigned char isapnp_read_byte(unsigned char idx)
{
	write_address(idx);
	return read_data();
}

static unsigned short isapnp_read_word(unsigned char idx)
{
	unsigned short val;

	val = isapnp_read_byte(idx);
	val = (val << 8) + isapnp_read_byte(idx + 1);
	return val;
}

void isapnp_write_byte(unsigned char idx, unsigned char val)
{
	write_address(idx);
	write_data(val);
}

static void isapnp_write_word(unsigned char idx, unsigned short val)
{
	isapnp_write_byte(idx, val >> 8);
	isapnp_write_byte(idx + 1, val);
}

static void isapnp_key(void)
{
	unsigned char code = 0x6a, msb;
	int i;

	mdelay(1);
	write_address(0x00);
	write_address(0x00);

	write_address(code);

	for (i = 1; i < 32; i++) {
		msb = ((code & 0x01) ^ ((code & 0x02) >> 1)) << 7;
		code = (code >> 1) | msb;
		write_address(code);
	}
}

/* place all pnp cards in wait-for-key state */
static void isapnp_wait(void)
{
	isapnp_write_byte(0x02, 0x02);
}

static void isapnp_wake(unsigned char csn)
{
	isapnp_write_byte(0x03, csn);
}

static void isapnp_device(unsigned char logdev)
{
	isapnp_write_byte(0x07, logdev);
}

static void isapnp_activate(unsigned char logdev)
{
	isapnp_device(logdev);
	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 1);
	udelay(250);
}

static void isapnp_deactivate(unsigned char logdev)
{
	isapnp_device(logdev);
	isapnp_write_byte(ISAPNP_CFG_ACTIVATE, 0);
	udelay(500);
}

static void __init isapnp_peek(unsigned char *data, int bytes)
{
	int i, j;
	unsigned char d = 0;

	for (i = 1; i <= bytes; i++) {
		for (j = 0; j < 20; j++) {
			d = isapnp_read_byte(0x05);
			if (d & 1)
				break;
			udelay(100);
		}
		if (!(d & 1)) {
			if (data != NULL)
				*data++ = 0xff;
			continue;
		}
		d = isapnp_read_byte(0x04);	/* PRESDI */
		isapnp_checksum_value += d;
		if (data != NULL)
			*data++ = d;
	}
}

#define RDP_STEP	32	/* minimum is 4 */

static int isapnp_next_rdp(void)
{
	int rdp = isapnp_rdp;
	static int old_rdp = 0;

	if (old_rdp) {
		release_region(old_rdp, 1);
		old_rdp = 0;
	}
	while (rdp <= 0x3ff) {
		/*
		 *      We cannot use NE2000 probe spaces for ISAPnP or we
		 *      will lock up machines.
		 */
		if ((rdp < 0x280 || rdp > 0x380)
		    && request_region(rdp, 1, "ISAPnP")) {
			isapnp_rdp = rdp;
			old_rdp = rdp;
			return 0;
		}
		rdp += RDP_STEP;
	}
	return -1;
}

/* Set read port address */
static inline void isapnp_set_rdp(void)
{
	isapnp_write_byte(0x00, isapnp_rdp >> 2);
	udelay(100);
}

/*
 *	Perform an isolation. The port selection code now tries to avoid
 *	"dangerous to read" ports.
 */
static int __init isapnp_isolate_rdp_select(void)
{
	isapnp_wait();
	isapnp_key();

	/* Control: reset CSN and conditionally everything else too */
	isapnp_write_byte(0x02, isapnp_reset ? 0x05 : 0x04);
	mdelay(2);

	isapnp_wait();
	isapnp_key();
	isapnp_wake(0x00);

	if (isapnp_next_rdp() < 0) {
		isapnp_wait();
		return -1;
	}

	isapnp_set_rdp();
	udelay(1000);
	write_address(0x01);
	udelay(1000);
	return 0;
}

/*
 *  Isolate (assign uniqued CSN) to all ISA PnP devices.
 */
static int __init isapnp_isolate(void)
{
	unsigned char checksum = 0x6a;
	unsigned char chksum = 0x00;
	unsigned char bit = 0x00;
	int data;
	int csn = 0;
	int i;
	int iteration = 1;

	isapnp_rdp = 0x213;
	if (isapnp_isolate_rdp_select() < 0)
		return -1;

	while (1) {
		for (i = 1; i <= 64; i++) {
			data = read_data() << 8;
			udelay(250);
			data = data | read_data();
			udelay(250);
			if (data == 0x55aa)
				bit = 0x01;
			checksum =
			    ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
			    | (checksum >> 1);
			bit = 0x00;
		}
		for (i = 65; i <= 72; i++) {
			data = read_data() << 8;
			udelay(250);
			data = data | read_data();
			udelay(250);
			if (data == 0x55aa)
				chksum |= (1 << (i - 65));
		}
		if (checksum != 0x00 && checksum == chksum) {
			csn++;

			isapnp_write_byte(0x06, csn);
			udelay(250);
			iteration++;
			isapnp_wake(0x00);
			isapnp_set_rdp();
			udelay(1000);
			write_address(0x01);
			udelay(1000);
			goto __next;
		}
		if (iteration == 1) {
			isapnp_rdp += RDP_STEP;
			if (isapnp_isolate_rdp_select() < 0)
				return -1;
		} else if (iteration > 1) {
			break;
		}
__next:
		if (csn == 255)
			break;
		checksum = 0x6a;
		chksum = 0x00;
		bit = 0x00;
	}
	isapnp_wait();
	isapnp_csn_count = csn;
	return csn;
}

/*
 *  Read one tag from stream.
 */
static int __init isapnp_read_tag(unsigned char *type, unsigned short *size)
{
	unsigned char tag, tmp[2];

	isapnp_peek(&tag, 1);
	if (tag == 0)		/* invalid tag */
		return -1;
	if (tag & 0x80) {	/* large item */
		*type = tag;
		isapnp_peek(tmp, 2);
		*size = (tmp[1] << 8) | tmp[0];
	} else {
		*type = (tag >> 3) & 0x0f;
		*size = tag & 0x07;
	}
#if 0
	printk(KERN_DEBUG "tag = 0x%x, type = 0x%x, size = %i\n", tag, *type,
	       *size);
#endif
	if (*type == 0xff && *size == 0xffff)	/* probably invalid data */
		return -1;
	return 0;
}

/*
 *  Skip specified number of bytes from stream.
 */
static void __init isapnp_skip_bytes(int count)
{
	isapnp_peek(NULL, count);
}

/*
 *  Parse logical device tag.
 */
static struct pnp_dev *__init isapnp_parse_device(struct pnp_card *card,
						  int size, int number)
{
	unsigned char tmp[6];
	struct pnp_dev *dev;
	u32 eisa_id;
	char id[8];

	isapnp_peek(tmp, size);
	eisa_id = tmp[0] | tmp[1] << 8 | tmp[2] << 16 | tmp[3] << 24;
	pnp_eisa_id_to_string(eisa_id, id);

	dev = pnp_alloc_dev(&isapnp_protocol, number, id);
	if (!dev)
		return NULL;

	dev->regs = tmp[4];
	dev->card = card;
	if (size > 5)
		dev->regs |= tmp[5] << 8;
	dev->capabilities |= PNP_CONFIGURABLE;
	dev->capabilities |= PNP_READ;
	dev->capabilities |= PNP_WRITE;
	dev->capabilities |= PNP_DISABLE;
	pnp_init_resources(dev);
	return dev;
}

/*
 *  Add IRQ resource to resources list.
 */
static void __init isapnp_parse_irq_resource(struct pnp_dev *dev,
					     struct pnp_option *option,
					     int size)
{
	unsigned char tmp[3];
	struct pnp_irq *irq;
	unsigned long bits;

	isapnp_peek(tmp, size);
	irq = kzalloc(sizeof(struct pnp_irq), GFP_KERNEL);
	if (!irq)
		return;
	bits = (tmp[1] << 8) | tmp[0];
	bitmap_copy(irq->map, &bits, 16);
	if (size > 2)
		irq->flags = tmp[2];
	else
		irq->flags = IORESOURCE_IRQ_HIGHEDGE;
	pnp_register_irq_resource(dev, option, irq);
}

/*
 *  Add DMA resource to resources list.
 */
static void __init isapnp_parse_dma_resource(struct pnp_dev *dev,
					     struct pnp_option *option,
					     int size)
{
	unsigned char tmp[2];
	struct pnp_dma *dma;

	isapnp_peek(tmp, size);
	dma = kzalloc(sizeof(struct pnp_dma), GFP_KERNEL);
	if (!dma)
		return;
	dma->map = tmp[0];
	dma->flags = tmp[1];
	pnp_register_dma_resource(dev, option, dma);
}

/*
 *  Add port resource to resources list.
 */
static void __init isapnp_parse_port_resource(struct pnp_dev *dev,
					      struct pnp_option *option,
					      int size)
{
	unsigned char tmp[7];
	struct pnp_port *port;

	isapnp_peek(tmp, size);
	port = kzalloc(sizeof(struct pnp_port), GFP_KERNEL);
	if (!port)
		return;
	port->min = (tmp[2] << 8) | tmp[1];
	port->max = (tmp[4] << 8) | tmp[3];
	port->align = tmp[5];
	port->size = tmp[6];
	port->flags = tmp[0] ? PNP_PORT_FLAG_16BITADDR : 0;
	pnp_register_port_resource(dev, option, port);
}

/*
 *  Add fixed port resource to resources list.
 */
static void __init isapnp_parse_fixed_port_resource(struct pnp_dev *dev,
						    struct pnp_option *option,
						    int size)
{
	unsigned char tmp[3];
	struct pnp_port *port;

	isapnp_peek(tmp, size);
	port = kzalloc(sizeof(struct pnp_port), GFP_KERNEL);
	if (!port)
		return;
	port->min = port->max = (tmp[1] << 8) | tmp[0];
	port->size = tmp[2];
	port->align = 0;
	port->flags = PNP_PORT_FLAG_FIXED;
	pnp_register_port_resource(dev, option, port);
}

/*
 *  Add memory resource to resources list.
 */
static void __init isapnp_parse_mem_resource(struct pnp_dev *dev,
					     struct pnp_option *option,
					     int size)
{
	unsigned char tmp[9];
	struct pnp_mem *mem;

	isapnp_peek(tmp, size);
	mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
	if (!mem)
		return;
	mem->min = ((tmp[2] << 8) | tmp[1]) << 8;
	mem->max = ((tmp[4] << 8) | tmp[3]) << 8;
	mem->align = (tmp[6] << 8) | tmp[5];
	mem->size = ((tmp[8] << 8) | tmp[7]) << 8;
	mem->flags = tmp[0];
	pnp_register_mem_resource(dev, option, mem);
}

/*
 *  Add 32-bit memory resource to resources list.
 */
static void __init isapnp_parse_mem32_resource(struct pnp_dev *dev,
					       struct pnp_option *option,
					       int size)
{
	unsigned char tmp[17];
	struct pnp_mem *mem;

	isapnp_peek(tmp, size);
	mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
	if (!mem)
		return;
	mem->min = (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
	mem->max = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
	mem->align =
	    (tmp[12] << 24) | (tmp[11] << 16) | (tmp[10] << 8) | tmp[9];
	mem->size =
	    (tmp[16] << 24) | (tmp[15] << 16) | (tmp[14] << 8) | tmp[13];
	mem->flags = tmp[0];
	pnp_register_mem_resource(dev, option, mem);
}

/*
 *  Add 32-bit fixed memory resource to resources list.
 */
static void __init isapnp_parse_fixed_mem32_resource(struct pnp_dev *dev,
						     struct pnp_option *option,
						     int size)
{
	unsigned char tmp[9];
	struct pnp_mem *mem;

	isapnp_peek(tmp, size);
	mem = kzalloc(sizeof(struct pnp_mem), GFP_KERNEL);
	if (!mem)
		return;
	mem->min = mem->max =
	    (tmp[4] << 24) | (tmp[3] << 16) | (tmp[2] << 8) | tmp[1];
	mem->size = (tmp[8] << 24) | (tmp[7] << 16) | (tmp[6] << 8) | tmp[5];
	mem->align = 0;
	mem->flags = tmp[0];
	pnp_register_mem_resource(dev, option, mem);
}

/*
 *  Parse card name for ISA PnP device.
 */
static void __init
isapnp_parse_name(char *name, unsigned int name_max, unsigned short *size)
{
	if (name[0] == '\0') {
		unsigned short size1 =
		    *size >= name_max ? (name_max - 1) : *size;
		isapnp_peek(name, size1);
		name[size1] = '\0';
		*size -= size1;

		/* clean whitespace from end of string */
		while (size1 > 0 && name[--size1] == ' ')
			name[size1] = '\0';
	}
}

/*
 *  Parse resource map for logical device.
 */
static int __init isapnp_create_device(struct pnp_card *card,
				       unsigned short size)
{
	int number = 0, skip = 0, priority = 0, compat = 0;
	unsigned char type, tmp[17];
	struct pnp_option *option;
	struct pnp_dev *dev;
	u32 eisa_id;
	char id[8];

	if ((dev = isapnp_parse_device(card, size, number++)) == NULL)
		return 1;
	option = pnp_register_independent_option(dev);
	if (!option) {
		kfree(dev);
		return 1;
	}
	pnp_add_card_device(card, dev);

	while (1) {
		if (isapnp_read_tag(&type, &size) < 0)
			return 1;
		if (skip && type != _STAG_LOGDEVID && type != _STAG_END)
			goto __skip;
		switch (type) {
		case _STAG_LOGDEVID:
			if (size >= 5 && size <= 6) {
				if ((dev =
				     isapnp_parse_device(card, size,
							 number++)) == NULL)
					return 1;
				size = 0;
				skip = 0;
				option = pnp_register_independent_option(dev);
				if (!option) {
					kfree(dev);
					return 1;
				}
				pnp_add_card_device(card, dev);
			} else {
				skip = 1;
			}
			priority = 0;
			compat = 0;
			break;
		case _STAG_COMPATDEVID:
			if (size == 4 && compat < DEVICE_COUNT_COMPATIBLE) {
				isapnp_peek(tmp, 4);
				eisa_id = tmp[0] | tmp[1] << 8 |
					  tmp[2] << 16 | tmp[3] << 24;
				pnp_eisa_id_to_string(eisa_id, id);
				pnp_add_id(dev, id);
				compat++;
				size = 0;
			}
			break;
		case _STAG_IRQ:
			if (size < 2 || size > 3)
				goto __skip;
			isapnp_parse_irq_resource(dev, option, size);
			size = 0;
			break;
		case _STAG_DMA:
			if (size != 2)
				goto __skip;
			isapnp_parse_dma_resource(dev, option, size);
			size = 0;
			break;
		case _STAG_STARTDEP:
			if (size > 1)
				goto __skip;
			priority = 0x100 | PNP_RES_PRIORITY_ACCEPTABLE;
			if (size > 0) {
				isapnp_peek(tmp, size);
				priority = 0x100 | tmp[0];
				size = 0;
			}
			option = pnp_register_dependent_option(dev, priority);
			if (!option)
				return 1;
			break;
		case _STAG_ENDDEP:
			if (size != 0)
				goto __skip;
			priority = 0;
			dev_dbg(&dev->dev, "end dependent options\n");
			break;
		case _STAG_IOPORT:
			if (size != 7)
				goto __skip;
			isapnp_parse_port_resource(dev, option, size);
			size = 0;
			break;
		case _STAG_FIXEDIO:
			if (size != 3)
				goto __skip;
			isapnp_parse_fixed_port_resource(dev, option, size);
			size = 0;
			break;
		case _STAG_VENDOR:
			break;
		case _LTAG_MEMRANGE:
			if (size != 9)
				goto __skip;
			isapnp_parse_mem_resource(dev, option, size);
			size = 0;
			break;
		case _LTAG_ANSISTR:
			isapnp_parse_name(dev->name, sizeof(dev->name), &size);
			break;
		case _LTAG_UNICODESTR:
			/* silently ignore */
			/* who use unicode for hardware identification? */
			break;
		case _LTAG_VENDOR:
			break;
		case _LTAG_MEM32RANGE:
			if (size != 17)
				goto __skip;
			isapnp_parse_mem32_resource(dev, option, size);
			size = 0;
			break;
		case _LTAG_FIXEDMEM32RANGE:
			if (size != 9)
				goto __skip;
			isapnp_parse_fixed_mem32_resource(dev, option, size);
			size = 0;
			break;
		case _STAG_END:
			if (size > 0)
				isapnp_skip_bytes(size);
			return 1;
		default:
			dev_err(&dev->dev, "unknown tag %#x (card %i), "
				"ignored\n", type, card->number);
		}
__skip:
		if (size > 0)
			isapnp_skip_bytes(size);
	}
	return 0;
}

/*
 *  Parse resource map for ISA PnP card.
 */
static void __init isapnp_parse_resource_map(struct pnp_card *card)
{
	unsigned char type, tmp[17];
	unsigned short size;

	while (1) {
		if (isapnp_read_tag(&type, &size) < 0)
			return;
		switch (type) {
		case _STAG_PNPVERNO:
			if (size != 2)
				goto __skip;
			isapnp_peek(tmp, 2);
			card->pnpver = tmp[0];
			card->productver = tmp[1];
			size = 0;
			break;
		case _STAG_LOGDEVID:
			if (size >= 5 && size <= 6) {
				if (isapnp_create_device(card, size) == 1)
					return;
				size = 0;
			}
			break;
		case _STAG_VENDOR:
			break;
		case _LTAG_ANSISTR:
			isapnp_parse_name(card->name, sizeof(card->name),
					  &size);
			break;
		case _LTAG_UNICODESTR:
			/* silently ignore */
			/* who use unicode for hardware identification? */
			break;
		case _LTAG_VENDOR:
			break;
		case _STAG_END:
			if (size > 0)
				isapnp_skip_bytes(size);
			return;
		default:
			dev_err(&card->dev, "unknown tag %#x, ignored\n",
			       type);
		}
__skip:
		if (size > 0)
			isapnp_skip_bytes(size);
	}
}

/*
 *  Compute ISA PnP checksum for first eight bytes.
 */
static unsigned char __init isapnp_checksum(unsigned char *data)
{
	int i, j;
	unsigned char checksum = 0x6a, bit, b;

	for (i = 0; i < 8; i++) {
		b = data[i];
		for (j = 0; j < 8; j++) {
			bit = 0;
			if (b & (1 << j))
				bit = 1;
			checksum =
			    ((((checksum ^ (checksum >> 1)) & 0x01) ^ bit) << 7)
			    | (checksum >> 1);
		}
	}
	return checksum;
}

/*
 *  Build device list for all present ISA PnP devices.
 */
static int __init isapnp_build_device_list(void)
{
	int csn;
	unsigned char header[9], checksum;
	struct pnp_card *card;
	u32 eisa_id;
	char id[8];

	isapnp_wait();
	isapnp_key();
	for (csn = 1; csn <= isapnp_csn_count; csn++) {
		isapnp_wake(csn);
		isapnp_peek(header, 9);
		checksum = isapnp_checksum(header);
		eisa_id = header[0] | header[1] << 8 |
			  header[2] << 16 | header[3] << 24;
		pnp_eisa_id_to_string(eisa_id, id);
		card = pnp_alloc_card(&isapnp_protocol, csn, id);
		if (!card)
			continue;

#if 0
		dev_info(&card->dev,
		       "vendor: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
		       header[0], header[1], header[2], header[3], header[4],
		       header[5], header[6], header[7], header[8]);
		dev_info(&card->dev, "checksum = %#x\n", checksum);
#endif
		INIT_LIST_HEAD(&card->devices);
		card->serial =
		    (header[7] << 24) | (header[6] << 16) | (header[5] << 8) |
		    header[4];
		isapnp_checksum_value = 0x00;
		isapnp_parse_resource_map(card);
		if (isapnp_checksum_value != 0x00)
			dev_err(&card->dev, "invalid checksum %#x\n",
				isapnp_checksum_value);
		card->checksum = isapnp_checksum_value;

		pnp_add_card(card);
	}
	isapnp_wait();
	return 0;
}

/*
 *  Basic configuration routines.
 */

int isapnp_present(void)
{
	struct pnp_card *card;

	pnp_for_each_card(card) {
		if (card->protocol == &isapnp_protocol)
			return 1;
	}
	return 0;
}

int isapnp_cfg_begin(int csn, int logdev)
{
	if (csn < 1 || csn > isapnp_csn_count || logdev > 10)
		return -EINVAL;
	mutex_lock(&isapnp_cfg_mutex);
	isapnp_wait();
	isapnp_key();
	isapnp_wake(csn);
#if 0
	/* to avoid malfunction when the isapnptools package is used */
	/* we must set RDP to our value again */
	/* it is possible to set RDP only in the isolation phase */
	/*   Jens Thoms Toerring <Jens.Toerring@physik.fu-berlin.de> */
	isapnp_write_byte(0x02, 0x04);	/* clear CSN of card */
	mdelay(2);		/* is this necessary? */
	isapnp_wake(csn);	/* bring card into sleep state */
	isapnp_wake(0);		/* bring card into isolation state */
	isapnp_set_rdp();	/* reset the RDP port */
	udelay(1000);		/* delay 1000us */
	isapnp_write_byte(0x06, csn);	/* reset CSN to previous value */
	udelay(250);		/* is this necessary? */
#endif
	if (logdev >= 0)
		isapnp_device(logdev);
	return 0;
}

int isapnp_cfg_end(void)
{
	isapnp_wait();
	mutex_unlock(&isapnp_cfg_mutex);
	return 0;
}

/*
 *  Initialization.
 */

EXPORT_SYMBOL(isapnp_protocol);
EXPORT_SYMBOL(isapnp_present);
EXPORT_SYMBOL(isapnp_cfg_begin);
EXPORT_SYMBOL(isapnp_cfg_end);
EXPORT_SYMBOL(isapnp_write_byte);

static int isapnp_read_resources(struct pnp_dev *dev)
{
	struct pnp_resource *pnp_res;
	struct resource *res;
	int tmp, ret;

	dev->active = isapnp_read_byte(ISAPNP_CFG_ACTIVATE);
	if (dev->active) {
		for (tmp = 0; tmp < ISAPNP_MAX_PORT; tmp++) {
			ret = isapnp_read_word(ISAPNP_CFG_PORT + (tmp << 1));
			if (!ret)
				continue;
			pnp_res = pnp_get_pnp_resource(dev, IORESOURCE_IO, tmp);
			pnp_res->index = tmp;
			res = &pnp_res->res;
			res->start = ret;
			res->flags = IORESOURCE_IO;
		}
		for (tmp = 0; tmp < ISAPNP_MAX_MEM; tmp++) {
			ret =
			    isapnp_read_word(ISAPNP_CFG_MEM + (tmp << 3)) << 8;
			if (!ret)
				continue;
			pnp_res = pnp_get_pnp_resource(dev, IORESOURCE_MEM,
						       tmp);
			pnp_res->index = tmp;
			res = &pnp_res->res;
			res->start = ret;
			res->flags = IORESOURCE_MEM;
		}
		for (tmp = 0; tmp < ISAPNP_MAX_IRQ; tmp++) {
			ret =
			    (isapnp_read_word(ISAPNP_CFG_IRQ + (tmp << 1)) >>
			     8);
			if (!ret)
				continue;
			pnp_res = pnp_add_irq_resource(dev, ret, 0);
			if (pnp_res)
				pnp_res->index = tmp;
		}
		for (tmp = 0; tmp < ISAPNP_MAX_DMA; tmp++) {
			ret = isapnp_read_byte(ISAPNP_CFG_DMA + tmp);
			if (ret == 4)
				continue;
			pnp_res = pnp_add_dma_resource(dev, ret, 0);
			if  (pnp_res)
				pnp_res->index = tmp;
		}
	}
	return 0;
}

static int isapnp_get_resources(struct pnp_dev *dev)
{
	int ret;

	dev_dbg(&dev->dev, "get resources\n");
	pnp_init_resources(dev);
	isapnp_cfg_begin(dev->card->number, dev->number);
	ret = isapnp_read_resources(dev);
	isapnp_cfg_end();
	return ret;
}

static int isapnp_set_resources(struct pnp_dev *dev)
{
	struct pnp_resource *pnp_res;
	struct resource *res;
	int tmp, index;

	dev_dbg(&dev->dev, "set resources\n");
	isapnp_cfg_begin(dev->card->number, dev->number);
	dev->active = 1;
	for (tmp = 0; tmp < ISAPNP_MAX_PORT; tmp++) {
		pnp_res = pnp_get_pnp_resource(dev, IORESOURCE_IO, tmp);
		if (!pnp_res)
			continue;
		res = &pnp_res->res;
		if (pnp_resource_valid(res)) {
			index = pnp_res->index;
			dev_dbg(&dev->dev, "  set io  %d to %#llx\n",
				index, (unsigned long long) res->start);
			isapnp_write_word(ISAPNP_CFG_PORT + (index << 1),
					  res->start);
		}
	}
	for (tmp = 0; tmp < ISAPNP_MAX_IRQ; tmp++) {
		pnp_res = pnp_get_pnp_resource(dev, IORESOURCE_IRQ, tmp);
		if (!pnp_res)
			continue;
		res = &pnp_res->res;
		if (pnp_resource_valid(res)) {
			int irq = res->start;
			if (irq == 2)
				irq = 9;
			index = pnp_res->index;
			dev_dbg(&dev->dev, "  set irq %d to %d\n", index, irq);
			isapnp_write_byte(ISAPNP_CFG_IRQ + (index << 1), irq);
		}
	}
	for (tmp = 0; tmp < ISAPNP_MAX_DMA; tmp++) {
		pnp_res = pnp_get_pnp_resource(dev, IORESOURCE_DMA, tmp);
		if (!pnp_res)
			continue;
		res = &pnp_res->res;
		if (pnp_resource_valid(res)) {
			index = pnp_res->index;
			dev_dbg(&dev->dev, "  set dma %d to %lld\n",
				index, (unsigned long long) res->start);
			isapnp_write_byte(ISAPNP_CFG_DMA + index, res->start);
		}
	}
	for (tmp = 0; tmp < ISAPNP_MAX_MEM; tmp++) {
		pnp_res = pnp_get_pnp_resource(dev, IORESOURCE_MEM, tmp);
		if (!pnp_res)
			continue;
		res = &pnp_res->res;
		if (pnp_resource_valid(res)) {
			index = pnp_res->index;
			dev_dbg(&dev->dev, "  set mem %d to %#llx\n",
				index, (unsigned long long) res->start);
			isapnp_write_word(ISAPNP_CFG_MEM + (index << 3),
					  (res->start >> 8) & 0xffff);
		}
	}
	/* FIXME: We aren't handling 32bit mems properly here */
	isapnp_activate(dev->number);
	isapnp_cfg_end();
	return 0;
}

static int isapnp_disable_resources(struct pnp_dev *dev)
{
	if (!dev->active)
		return -EINVAL;
	isapnp_cfg_begin(dev->card->number, dev->number);
	isapnp_deactivate(dev->number);
	dev->active = 0;
	isapnp_cfg_end();
	return 0;
}

struct pnp_protocol isapnp_protocol = {
	.name = "ISA Plug and Play",
	.get = isapnp_get_resources,
	.set = isapnp_set_resources,
	.disable = isapnp_disable_resources,
};

static int __init isapnp_init(void)
{
	int cards;
	struct pnp_card *card;
	struct pnp_dev *dev;

	if (isapnp_disable) {
		printk(KERN_INFO "isapnp: ISA Plug & Play support disabled\n");
		return 0;
	}
#ifdef CONFIG_PPC_MERGE
	if (check_legacy_ioport(_PIDXR) || check_legacy_ioport(_PNPWRP))
		return -EINVAL;
#endif
#ifdef ISAPNP_REGION_OK
	if (!request_region(_PIDXR, 1, "isapnp index")) {
		printk(KERN_ERR "isapnp: Index Register 0x%x already used\n",
		       _PIDXR);
		return -EBUSY;
	}
#endif
	if (!request_region(_PNPWRP, 1, "isapnp write")) {
		printk(KERN_ERR
		       "isapnp: Write Data Register 0x%x already used\n",
		       _PNPWRP);
#ifdef ISAPNP_REGION_OK
		release_region(_PIDXR, 1);
#endif
		return -EBUSY;
	}

	if (pnp_register_protocol(&isapnp_protocol) < 0)
		return -EBUSY;

	/*
	 *      Print a message. The existing ISAPnP code is hanging machines
	 *      so let the user know where.
	 */

	printk(KERN_INFO "isapnp: Scanning for PnP cards...\n");
	if (isapnp_rdp >= 0x203 && isapnp_rdp <= 0x3ff) {
		isapnp_rdp |= 3;
		if (!request_region(isapnp_rdp, 1, "isapnp read")) {
			printk(KERN_ERR
			       "isapnp: Read Data Register 0x%x already used\n",
			       isapnp_rdp);
#ifdef ISAPNP_REGION_OK
			release_region(_PIDXR, 1);
#endif
			release_region(_PNPWRP, 1);
			return -EBUSY;
		}
		isapnp_set_rdp();
	}
	if (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff) {
		cards = isapnp_isolate();
		if (cards < 0 || (isapnp_rdp < 0x203 || isapnp_rdp > 0x3ff)) {
#ifdef ISAPNP_REGION_OK
			release_region(_PIDXR, 1);
#endif
			release_region(_PNPWRP, 1);
			printk(KERN_INFO
			       "isapnp: No Plug & Play device found\n");
			return 0;
		}
		request_region(isapnp_rdp, 1, "isapnp read");
	}
	isapnp_build_device_list();
	cards = 0;

	protocol_for_each_card(&isapnp_protocol, card) {
		cards++;
		if (isapnp_verbose) {
			dev_info(&card->dev, "card '%s'\n",
			       card->name[0] ? card->name : "unknown");
			if (isapnp_verbose < 2)
				continue;
			card_for_each_dev(card, dev) {
				dev_info(&card->dev, "device '%s'\n",
				       dev->name[0] ? dev->name : "unknown");
			}
		}
	}
	if (cards)
		printk(KERN_INFO
		       "isapnp: %i Plug & Play card%s detected total\n", cards,
		       cards > 1 ? "s" : "");
	else
		printk(KERN_INFO "isapnp: No Plug & Play card found\n");

	isapnp_proc_init();
	return 0;
}

device_initcall(isapnp_init);

/* format is: noisapnp */

static int __init isapnp_setup_disable(char *str)
{
	isapnp_disable = 1;
	return 1;
}

__setup("noisapnp", isapnp_setup_disable);

/* format is: isapnp=rdp,reset,skip_pci_scan,verbose */

static int __init isapnp_setup_isapnp(char *str)
{
	(void)((get_option(&str, &isapnp_rdp) == 2) &&
	       (get_option(&str, &isapnp_reset) == 2) &&
	       (get_option(&str, &isapnp_verbose) == 2));
	return 1;
}

__setup("isapnp=", isapnp_setup_isapnp);