Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
   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
/*
 *	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.
 *
 *	Original driver code supplied by Multi-Tech
 *
 *	Changes
 *	1/9/98	alan@lxorguk.ukuu.org.uk
 *					Merge to 2.0.x kernel tree
 *					Obtain and use official major/minors
 *					Loader switched to a misc device
 *					(fixed range check bug as a side effect)
 *					Printk clean up
 *	9/12/98	alan@lxorguk.ukuu.org.uk
 *					Rough port to 2.1.x
 *
 *	10/6/99 sameer			Merged the ISA and PCI drivers to
 *					a new unified driver.
 *
 *	3/9/99	sameer			Added support for ISI4616 cards.
 *
 *	16/9/99	sameer			We do not force RTS low anymore.
 *					This is to prevent the firmware
 *					from getting confused.
 *
 *	26/10/99 sameer			Cosmetic changes:The driver now
 *					dumps the Port Count information
 *					along with I/O address and IRQ.
 *
 *	13/12/99 sameer			Fixed the problem with IRQ sharing.
 *
 *	10/5/00  sameer			Fixed isicom_shutdown_board()
 *					to not lower DTR on all the ports
 *					when the last port on the card is
 *					closed.
 *
 *	10/5/00  sameer			Signal mask setup command added
 *					to  isicom_setup_port and
 *					isicom_shutdown_port.
 *
 *	24/5/00  sameer			The driver is now SMP aware.
 *
 *
 *	27/11/00 Vinayak P Risbud	Fixed the Driver Crash Problem
 *
 *
 *	03/01/01  anil .s		Added support for resetting the
 *					internal modems on ISI cards.
 *
 *	08/02/01  anil .s		Upgraded the driver for kernel
 *					2.4.x
 *
 *	11/04/01  Kevin			Fixed firmware load problem with
 *					ISIHP-4X card
 *
 *	30/04/01  anil .s		Fixed the remote login through
 *					ISI port problem. Now the link
 *					does not go down before password
 *					prompt.
 *
 *	03/05/01  anil .s		Fixed the problem with IRQ sharing
 *					among ISI-PCI cards.
 *
 *	03/05/01  anil .s		Added support to display the version
 *					info during insmod as well as module
 *					listing by lsmod.
 *
 *	10/05/01  anil .s		Done the modifications to the source
 *					file and Install script so that the
 *					same installation can be used for
 *					2.2.x and 2.4.x kernel.
 *
 *	06/06/01  anil .s		Now we drop both dtr and rts during
 *					shutdown_port as well as raise them
 *					during isicom_config_port.
 *
 *	09/06/01 acme@conectiva.com.br	use capable, not suser, do
 *					restore_flags on failure in
 *					isicom_send_break, verify put_user
 *					result
 *
 *	11/02/03  ranjeeth		Added support for 230 Kbps and 460 Kbps
 *					Baud index extended to 21
 *
 *	20/03/03  ranjeeth		Made to work for Linux Advanced server.
 *					Taken care of license warning.
 *
 *	10/12/03  Ravindra		Made to work for Fedora Core 1 of
 *					Red Hat Distribution
 *
 *	06/01/05  Alan Cox 		Merged the ISI and base kernel strands
 *					into a single 2.6 driver
 *
 *	***********************************************************
 *
 *	To use this driver you also need the support package. You
 *	can find this in RPM format on
 *		ftp://ftp.linux.org.uk/pub/linux/alan
 *
 *	You can find the original tools for this direct from Multitech
 *		ftp://ftp.multitech.com/ISI-Cards/
 *
 *	Having installed the cards the module options (/etc/modprobe.d/)
 *
 *	options isicom   io=card1,card2,card3,card4 irq=card1,card2,card3,card4
 *
 *	Omit those entries for boards you don't have installed.
 *
 *	TODO
 *		Merge testing
 *		64-bit verification
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/firmware.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/termios.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/serial.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/slab.h>

#include <linux/uaccess.h>
#include <linux/io.h>

#include <linux/pci.h>

#include <linux/isicom.h>

#define InterruptTheCard(base) outw(0, (base) + 0xc)
#define ClearInterrupt(base) inw((base) + 0x0a)

#ifdef DEBUG
#define isicom_paranoia_check(a, b, c) __isicom_paranoia_check((a), (b), (c))
#else
#define isicom_paranoia_check(a, b, c) 0
#endif

static int isicom_probe(struct pci_dev *, const struct pci_device_id *);
static void isicom_remove(struct pci_dev *);

static struct pci_device_id isicom_pci_tbl[] = {
	{ PCI_DEVICE(VENDOR_ID, 0x2028) },
	{ PCI_DEVICE(VENDOR_ID, 0x2051) },
	{ PCI_DEVICE(VENDOR_ID, 0x2052) },
	{ PCI_DEVICE(VENDOR_ID, 0x2053) },
	{ PCI_DEVICE(VENDOR_ID, 0x2054) },
	{ PCI_DEVICE(VENDOR_ID, 0x2055) },
	{ PCI_DEVICE(VENDOR_ID, 0x2056) },
	{ PCI_DEVICE(VENDOR_ID, 0x2057) },
	{ PCI_DEVICE(VENDOR_ID, 0x2058) },
	{ 0 }
};
MODULE_DEVICE_TABLE(pci, isicom_pci_tbl);

static struct pci_driver isicom_driver = {
	.name		= "isicom",
	.id_table	= isicom_pci_tbl,
	.probe		= isicom_probe,
	.remove		= isicom_remove
};

static int prev_card = 3;	/*	start servicing isi_card[0]	*/
static struct tty_driver *isicom_normal;

static void isicom_tx(unsigned long _data);
static void isicom_start(struct tty_struct *tty);

static DEFINE_TIMER(tx, isicom_tx, 0, 0);

/*   baud index mappings from linux defns to isi */

static signed char linuxb_to_isib[] = {
	-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 18, 19, 20, 21
};

struct	isi_board {
	unsigned long		base;
	int			irq;
	unsigned char		port_count;
	unsigned short		status;
	unsigned short		port_status; /* each bit for each port */
	unsigned short		shift_count;
	struct isi_port		*ports;
	signed char		count;
	spinlock_t		card_lock; /* Card wide lock 11/5/00 -sameer */
	unsigned long		flags;
	unsigned int		index;
};

struct	isi_port {
	unsigned short		magic;
	struct tty_port		port;
	u16			channel;
	u16			status;
	struct isi_board	*card;
	unsigned char		*xmit_buf;
	int			xmit_head;
	int			xmit_tail;
	int			xmit_cnt;
};

static struct isi_board isi_card[BOARD_COUNT];
static struct isi_port  isi_ports[PORT_COUNT];

/*
 *	Locking functions for card level locking. We need to own both
 *	the kernel lock for the card and have the card in a position that
 *	it wants to talk.
 */

static int WaitTillCardIsFree(unsigned long base)
{
	unsigned int count = 0;
	unsigned int a = in_atomic(); /* do we run under spinlock? */

	while (!(inw(base + 0xe) & 0x1) && count++ < 100)
		if (a)
			mdelay(1);
		else
			msleep(1);

	return !(inw(base + 0xe) & 0x1);
}

static int lock_card(struct isi_board *card)
{
	unsigned long base = card->base;
	unsigned int retries, a;

	for (retries = 0; retries < 10; retries++) {
		spin_lock_irqsave(&card->card_lock, card->flags);
		for (a = 0; a < 10; a++) {
			if (inw(base + 0xe) & 0x1)
				return 1;
			udelay(10);
		}
		spin_unlock_irqrestore(&card->card_lock, card->flags);
		msleep(10);
	}
	pr_warn("Failed to lock Card (0x%lx)\n", card->base);

	return 0;	/* Failed to acquire the card! */
}

static void unlock_card(struct isi_board *card)
{
	spin_unlock_irqrestore(&card->card_lock, card->flags);
}

/*
 *  ISI Card specific ops ...
 */

/* card->lock HAS to be held */
static void raise_dtr(struct isi_port *port)
{
	struct isi_board *card = port->card;
	unsigned long base = card->base;
	u16 channel = port->channel;

	if (WaitTillCardIsFree(base))
		return;

	outw(0x8000 | (channel << card->shift_count) | 0x02, base);
	outw(0x0504, base);
	InterruptTheCard(base);
	port->status |= ISI_DTR;
}

/* card->lock HAS to be held */
static void drop_dtr(struct isi_port *port)
{
	struct isi_board *card = port->card;
	unsigned long base = card->base;
	u16 channel = port->channel;

	if (WaitTillCardIsFree(base))
		return;

	outw(0x8000 | (channel << card->shift_count) | 0x02, base);
	outw(0x0404, base);
	InterruptTheCard(base);
	port->status &= ~ISI_DTR;
}

/* card->lock HAS to be held */
static inline void raise_rts(struct isi_port *port)
{
	struct isi_board *card = port->card;
	unsigned long base = card->base;
	u16 channel = port->channel;

	if (WaitTillCardIsFree(base))
		return;

	outw(0x8000 | (channel << card->shift_count) | 0x02, base);
	outw(0x0a04, base);
	InterruptTheCard(base);
	port->status |= ISI_RTS;
}

/* card->lock HAS to be held */
static inline void drop_rts(struct isi_port *port)
{
	struct isi_board *card = port->card;
	unsigned long base = card->base;
	u16 channel = port->channel;

	if (WaitTillCardIsFree(base))
		return;

	outw(0x8000 | (channel << card->shift_count) | 0x02, base);
	outw(0x0804, base);
	InterruptTheCard(base);
	port->status &= ~ISI_RTS;
}

/* card->lock MUST NOT be held */

static void isicom_dtr_rts(struct tty_port *port, int on)
{
	struct isi_port *ip = container_of(port, struct isi_port, port);
	struct isi_board *card = ip->card;
	unsigned long base = card->base;
	u16 channel = ip->channel;

	if (!lock_card(card))
		return;

	if (on) {
		outw(0x8000 | (channel << card->shift_count) | 0x02, base);
		outw(0x0f04, base);
		InterruptTheCard(base);
		ip->status |= (ISI_DTR | ISI_RTS);
	} else {
		outw(0x8000 | (channel << card->shift_count) | 0x02, base);
		outw(0x0C04, base);
		InterruptTheCard(base);
		ip->status &= ~(ISI_DTR | ISI_RTS);
	}
	unlock_card(card);
}

/* card->lock HAS to be held */
static void drop_dtr_rts(struct isi_port *port)
{
	struct isi_board *card = port->card;
	unsigned long base = card->base;
	u16 channel = port->channel;

	if (WaitTillCardIsFree(base))
		return;

	outw(0x8000 | (channel << card->shift_count) | 0x02, base);
	outw(0x0c04, base);
	InterruptTheCard(base);
	port->status &= ~(ISI_RTS | ISI_DTR);
}

/*
 *	ISICOM Driver specific routines ...
 *
 */

static inline int __isicom_paranoia_check(struct isi_port const *port,
	char *name, const char *routine)
{
	if (!port) {
		pr_warn("Warning: bad isicom magic for dev %s in %s\n",
			name, routine);
		return 1;
	}
	if (port->magic != ISICOM_MAGIC) {
		pr_warn("Warning: NULL isicom port for dev %s in %s\n",
			name, routine);
		return 1;
	}

	return 0;
}

/*
 *	Transmitter.
 *
 *	We shovel data into the card buffers on a regular basis. The card
 *	will do the rest of the work for us.
 */

static void isicom_tx(unsigned long _data)
{
	unsigned long flags, base;
	unsigned int retries;
	short count = (BOARD_COUNT-1), card;
	short txcount, wrd, residue, word_count, cnt;
	struct isi_port *port;
	struct tty_struct *tty;

	/*	find next active board	*/
	card = (prev_card + 1) & 0x0003;
	while (count-- > 0) {
		if (isi_card[card].status & BOARD_ACTIVE)
			break;
		card = (card + 1) & 0x0003;
	}
	if (!(isi_card[card].status & BOARD_ACTIVE))
		goto sched_again;

	prev_card = card;

	count = isi_card[card].port_count;
	port = isi_card[card].ports;
	base = isi_card[card].base;

	spin_lock_irqsave(&isi_card[card].card_lock, flags);
	for (retries = 0; retries < 100; retries++) {
		if (inw(base + 0xe) & 0x1)
			break;
		udelay(2);
	}
	if (retries >= 100)
		goto unlock;

	tty = tty_port_tty_get(&port->port);
	if (tty == NULL)
		goto put_unlock;

	for (; count > 0; count--, port++) {
		/* port not active or tx disabled to force flow control */
		if (!tty_port_initialized(&port->port) ||
			!(port->status & ISI_TXOK))
			continue;

		txcount = min_t(short, TX_SIZE, port->xmit_cnt);
		if (txcount <= 0 || tty->stopped || tty->hw_stopped)
			continue;

		if (!(inw(base + 0x02) & (1 << port->channel)))
			continue;

		pr_debug("txing %d bytes, port%d.\n",
			 txcount, port->channel + 1);
		outw((port->channel << isi_card[card].shift_count) | txcount,
			base);
		residue = NO;
		wrd = 0;
		while (1) {
			cnt = min_t(int, txcount, (SERIAL_XMIT_SIZE
					- port->xmit_tail));
			if (residue == YES) {
				residue = NO;
				if (cnt > 0) {
					wrd |= (port->port.xmit_buf[port->xmit_tail]
									<< 8);
					port->xmit_tail = (port->xmit_tail + 1)
						& (SERIAL_XMIT_SIZE - 1);
					port->xmit_cnt--;
					txcount--;
					cnt--;
					outw(wrd, base);
				} else {
					outw(wrd, base);
					break;
				}
			}
			if (cnt <= 0)
				break;
			word_count = cnt >> 1;
			outsw(base, port->port.xmit_buf+port->xmit_tail, word_count);
			port->xmit_tail = (port->xmit_tail
				+ (word_count << 1)) & (SERIAL_XMIT_SIZE - 1);
			txcount -= (word_count << 1);
			port->xmit_cnt -= (word_count << 1);
			if (cnt & 0x0001) {
				residue = YES;
				wrd = port->port.xmit_buf[port->xmit_tail];
				port->xmit_tail = (port->xmit_tail + 1)
					& (SERIAL_XMIT_SIZE - 1);
				port->xmit_cnt--;
				txcount--;
			}
		}

		InterruptTheCard(base);
		if (port->xmit_cnt <= 0)
			port->status &= ~ISI_TXOK;
		if (port->xmit_cnt <= WAKEUP_CHARS)
			tty_wakeup(tty);
	}

put_unlock:
	tty_kref_put(tty);
unlock:
	spin_unlock_irqrestore(&isi_card[card].card_lock, flags);
	/*	schedule another tx for hopefully in about 10ms	*/
sched_again:
	mod_timer(&tx, jiffies + msecs_to_jiffies(10));
}

/*
 *	Main interrupt handler routine
 */

static irqreturn_t isicom_interrupt(int irq, void *dev_id)
{
	struct isi_board *card = dev_id;
	struct isi_port *port;
	struct tty_struct *tty;
	unsigned long base;
	u16 header, word_count, count, channel;
	short byte_count;
	unsigned char *rp;

	if (!card || !(card->status & FIRMWARE_LOADED))
		return IRQ_NONE;

	base = card->base;

	/* did the card interrupt us? */
	if (!(inw(base + 0x0e) & 0x02))
		return IRQ_NONE;

	spin_lock(&card->card_lock);

	/*
	 * disable any interrupts from the PCI card and lower the
	 * interrupt line
	 */
	outw(0x8000, base+0x04);
	ClearInterrupt(base);

	inw(base);		/* get the dummy word out */
	header = inw(base);
	channel = (header & 0x7800) >> card->shift_count;
	byte_count = header & 0xff;

	if (channel + 1 > card->port_count) {
		pr_warn("%s(0x%lx): %d(channel) > port_count\n",
			__func__, base, channel + 1);
		outw(0x0000, base+0x04); /* enable interrupts */
		spin_unlock(&card->card_lock);
		return IRQ_HANDLED;
	}
	port = card->ports + channel;
	if (!tty_port_initialized(&port->port)) {
		outw(0x0000, base+0x04); /* enable interrupts */
		spin_unlock(&card->card_lock);
		return IRQ_HANDLED;
	}

	tty = tty_port_tty_get(&port->port);
	if (tty == NULL) {
		word_count = byte_count >> 1;
		while (byte_count > 1) {
			inw(base);
			byte_count -= 2;
		}
		if (byte_count & 0x01)
			inw(base);
		outw(0x0000, base+0x04); /* enable interrupts */
		spin_unlock(&card->card_lock);
		return IRQ_HANDLED;
	}

	if (header & 0x8000) {		/* Status Packet */
		header = inw(base);
		switch (header & 0xff) {
		case 0:	/* Change in EIA signals */
			if (tty_port_check_carrier(&port->port)) {
				if (port->status & ISI_DCD) {
					if (!(header & ISI_DCD)) {
					/* Carrier has been lost  */
						pr_debug("%s: DCD->low.\n",
							 __func__);
						port->status &= ~ISI_DCD;
						tty_hangup(tty);
					}
				} else if (header & ISI_DCD) {
				/* Carrier has been detected */
					pr_debug("%s: DCD->high.\n",
						__func__);
					port->status |= ISI_DCD;
					wake_up_interruptible(&port->port.open_wait);
				}
			} else {
				if (header & ISI_DCD)
					port->status |= ISI_DCD;
				else
					port->status &= ~ISI_DCD;
			}

			if (tty_port_cts_enabled(&port->port)) {
				if (tty->hw_stopped) {
					if (header & ISI_CTS) {
						tty->hw_stopped = 0;
						/* start tx ing */
						port->status |= (ISI_TXOK
							| ISI_CTS);
						tty_wakeup(tty);
					}
				} else if (!(header & ISI_CTS)) {
					tty->hw_stopped = 1;
					/* stop tx ing */
					port->status &= ~(ISI_TXOK | ISI_CTS);
				}
			} else {
				if (header & ISI_CTS)
					port->status |= ISI_CTS;
				else
					port->status &= ~ISI_CTS;
			}

			if (header & ISI_DSR)
				port->status |= ISI_DSR;
			else
				port->status &= ~ISI_DSR;

			if (header & ISI_RI)
				port->status |= ISI_RI;
			else
				port->status &= ~ISI_RI;

			break;

		case 1:	/* Received Break !!! */
			tty_insert_flip_char(&port->port, 0, TTY_BREAK);
			if (port->port.flags & ASYNC_SAK)
				do_SAK(tty);
			tty_flip_buffer_push(&port->port);
			break;

		case 2:	/* Statistics		 */
			pr_debug("%s: stats!!!\n", __func__);
			break;

		default:
			pr_debug("%s: Unknown code in status packet.\n",
				 __func__);
			break;
		}
	} else {				/* Data   Packet */
		count = tty_prepare_flip_string(&port->port, &rp,
				byte_count & ~1);
		pr_debug("%s: Can rx %d of %d bytes.\n",
			 __func__, count, byte_count);
		word_count = count >> 1;
		insw(base, rp, word_count);
		byte_count -= (word_count << 1);
		if (count & 0x0001) {
			tty_insert_flip_char(&port->port, inw(base) & 0xff,
				TTY_NORMAL);
			byte_count -= 2;
		}
		if (byte_count > 0) {
			pr_debug("%s(0x%lx:%d): Flip buffer overflow! dropping bytes...\n",
				 __func__, base, channel + 1);
		/* drain out unread xtra data */
		while (byte_count > 0) {
				inw(base);
				byte_count -= 2;
			}
		}
		tty_flip_buffer_push(&port->port);
	}
	outw(0x0000, base+0x04); /* enable interrupts */
	spin_unlock(&card->card_lock);
	tty_kref_put(tty);

	return IRQ_HANDLED;
}

static void isicom_config_port(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;
	struct isi_board *card = port->card;
	unsigned long baud;
	unsigned long base = card->base;
	u16 channel_setup, channel = port->channel,
		shift_count = card->shift_count;
	unsigned char flow_ctrl;

	/* FIXME: Switch to new tty baud API */
	baud = C_BAUD(tty);
	if (baud & CBAUDEX) {
		baud &= ~CBAUDEX;

		/*  if CBAUDEX bit is on and the baud is set to either 50 or 75
		 *  then the card is programmed for 57.6Kbps or 115Kbps
		 *  respectively.
		 */

		/* 1,2,3,4 => 57.6, 115.2, 230, 460 kbps resp. */
		if (baud < 1 || baud > 4)
			tty->termios.c_cflag &= ~CBAUDEX;
		else
			baud += 15;
	}
	if (baud == 15) {

		/*  the ASYNC_SPD_HI and ASYNC_SPD_VHI options are set
		 *  by the set_serial_info ioctl ... this is done by
		 *  the 'setserial' utility.
		 */

		if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
			baud++; /*  57.6 Kbps */
		if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
			baud += 2; /*  115  Kbps */
		if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
			baud += 3; /* 230 kbps*/
		if ((port->port.flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
			baud += 4; /* 460 kbps*/
	}
	if (linuxb_to_isib[baud] == -1) {
		/* hang up */
		drop_dtr(port);
		return;
	} else
		raise_dtr(port);

	if (WaitTillCardIsFree(base) == 0) {
		outw(0x8000 | (channel << shift_count) | 0x03, base);
		outw(linuxb_to_isib[baud] << 8 | 0x03, base);
		channel_setup = 0;
		switch (C_CSIZE(tty)) {
		case CS5:
			channel_setup |= ISICOM_CS5;
			break;
		case CS6:
			channel_setup |= ISICOM_CS6;
			break;
		case CS7:
			channel_setup |= ISICOM_CS7;
			break;
		case CS8:
			channel_setup |= ISICOM_CS8;
			break;
		}

		if (C_CSTOPB(tty))
			channel_setup |= ISICOM_2SB;
		if (C_PARENB(tty)) {
			channel_setup |= ISICOM_EVPAR;
			if (C_PARODD(tty))
				channel_setup |= ISICOM_ODPAR;
		}
		outw(channel_setup, base);
		InterruptTheCard(base);
	}
	tty_port_set_check_carrier(&port->port, !C_CLOCAL(tty));

	/* flow control settings ...*/
	flow_ctrl = 0;
	tty_port_set_cts_flow(&port->port, C_CRTSCTS(tty));
	if (C_CRTSCTS(tty))
		flow_ctrl |= ISICOM_CTSRTS;
	if (I_IXON(tty))
		flow_ctrl |= ISICOM_RESPOND_XONXOFF;
	if (I_IXOFF(tty))
		flow_ctrl |= ISICOM_INITIATE_XONXOFF;

	if (WaitTillCardIsFree(base) == 0) {
		outw(0x8000 | (channel << shift_count) | 0x04, base);
		outw(flow_ctrl << 8 | 0x05, base);
		outw((STOP_CHAR(tty)) << 8 | (START_CHAR(tty)), base);
		InterruptTheCard(base);
	}

	/*	rx enabled -> enable port for rx on the card	*/
	if (C_CREAD(tty)) {
		card->port_status |= (1 << channel);
		outw(card->port_status, base + 0x02);
	}
}

/* open et all */

static inline void isicom_setup_board(struct isi_board *bp)
{
	int channel;
	struct isi_port *port;

	bp->count++;
	if (!(bp->status & BOARD_INIT)) {
		port = bp->ports;
		for (channel = 0; channel < bp->port_count; channel++, port++)
			drop_dtr_rts(port);
	}
	bp->status |= BOARD_ACTIVE | BOARD_INIT;
}

/* Activate and thus setup board are protected from races against shutdown
   by the tty_port mutex */

static int isicom_activate(struct tty_port *tport, struct tty_struct *tty)
{
	struct isi_port *port = container_of(tport, struct isi_port, port);
	struct isi_board *card = port->card;
	unsigned long flags;

	if (tty_port_alloc_xmit_buf(tport) < 0)
		return -ENOMEM;

	spin_lock_irqsave(&card->card_lock, flags);
	isicom_setup_board(card);

	port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;

	/*	discard any residual data	*/
	if (WaitTillCardIsFree(card->base) == 0) {
		outw(0x8000 | (port->channel << card->shift_count) | 0x02,
				card->base);
		outw(((ISICOM_KILLTX | ISICOM_KILLRX) << 8) | 0x06, card->base);
		InterruptTheCard(card->base);
	}
	isicom_config_port(tty);
	spin_unlock_irqrestore(&card->card_lock, flags);

	return 0;
}

static int isicom_carrier_raised(struct tty_port *port)
{
	struct isi_port *ip = container_of(port, struct isi_port, port);
	return (ip->status & ISI_DCD)?1 : 0;
}

static struct tty_port *isicom_find_port(struct tty_struct *tty)
{
	struct isi_port *port;
	struct isi_board *card;
	unsigned int board;
	int line = tty->index;

	board = BOARD(line);
	card = &isi_card[board];

	if (!(card->status & FIRMWARE_LOADED))
		return NULL;

	/*  open on a port greater than the port count for the card !!! */
	if (line > ((board * 16) + card->port_count - 1))
		return NULL;

	port = &isi_ports[line];
	if (isicom_paranoia_check(port, tty->name, "isicom_open"))
		return NULL;

	return &port->port;
}

static int isicom_open(struct tty_struct *tty, struct file *filp)
{
	struct isi_port *port;
	struct tty_port *tport;

	tport = isicom_find_port(tty);
	if (tport == NULL)
		return -ENODEV;
	port = container_of(tport, struct isi_port, port);

	tty->driver_data = port;
	return tty_port_open(tport, tty, filp);
}

/* close et all */

/* card->lock HAS to be held */
static void isicom_shutdown_port(struct isi_port *port)
{
	struct isi_board *card = port->card;

	if (--card->count < 0) {
		pr_debug("%s: bad board(0x%lx) count %d.\n",
			 __func__, card->base, card->count);
		card->count = 0;
	}
	/* last port was closed, shutdown that board too */
	if (!card->count)
		card->status &= BOARD_ACTIVE;
}

static void isicom_flush_buffer(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;
	struct isi_board *card = port->card;
	unsigned long flags;

	if (isicom_paranoia_check(port, tty->name, "isicom_flush_buffer"))
		return;

	spin_lock_irqsave(&card->card_lock, flags);
	port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;
	spin_unlock_irqrestore(&card->card_lock, flags);

	tty_wakeup(tty);
}

static void isicom_shutdown(struct tty_port *port)
{
	struct isi_port *ip = container_of(port, struct isi_port, port);
	struct isi_board *card = ip->card;
	unsigned long flags;

	/* indicate to the card that no more data can be received
	   on this port */
	spin_lock_irqsave(&card->card_lock, flags);
	card->port_status &= ~(1 << ip->channel);
	outw(card->port_status, card->base + 0x02);
	isicom_shutdown_port(ip);
	spin_unlock_irqrestore(&card->card_lock, flags);
	tty_port_free_xmit_buf(port);
}

static void isicom_close(struct tty_struct *tty, struct file *filp)
{
	struct isi_port *ip = tty->driver_data;
	struct tty_port *port;

	if (ip == NULL)
		return;

	port = &ip->port;
	if (isicom_paranoia_check(ip, tty->name, "isicom_close"))
		return;
	tty_port_close(port, tty, filp);
}

/* write et all */
static int isicom_write(struct tty_struct *tty,	const unsigned char *buf,
	int count)
{
	struct isi_port *port = tty->driver_data;
	struct isi_board *card = port->card;
	unsigned long flags;
	int cnt, total = 0;

	if (isicom_paranoia_check(port, tty->name, "isicom_write"))
		return 0;

	spin_lock_irqsave(&card->card_lock, flags);

	while (1) {
		cnt = min_t(int, count, min(SERIAL_XMIT_SIZE - port->xmit_cnt
				- 1, SERIAL_XMIT_SIZE - port->xmit_head));
		if (cnt <= 0)
			break;

		memcpy(port->port.xmit_buf + port->xmit_head, buf, cnt);
		port->xmit_head = (port->xmit_head + cnt) & (SERIAL_XMIT_SIZE
			- 1);
		port->xmit_cnt += cnt;
		buf += cnt;
		count -= cnt;
		total += cnt;
	}
	if (port->xmit_cnt && !tty->stopped && !tty->hw_stopped)
		port->status |= ISI_TXOK;
	spin_unlock_irqrestore(&card->card_lock, flags);
	return total;
}

/* put_char et all */
static int isicom_put_char(struct tty_struct *tty, unsigned char ch)
{
	struct isi_port *port = tty->driver_data;
	struct isi_board *card = port->card;
	unsigned long flags;

	if (isicom_paranoia_check(port, tty->name, "isicom_put_char"))
		return 0;

	spin_lock_irqsave(&card->card_lock, flags);
	if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) {
		spin_unlock_irqrestore(&card->card_lock, flags);
		return 0;
	}

	port->port.xmit_buf[port->xmit_head++] = ch;
	port->xmit_head &= (SERIAL_XMIT_SIZE - 1);
	port->xmit_cnt++;
	spin_unlock_irqrestore(&card->card_lock, flags);
	return 1;
}

/* flush_chars et all */
static void isicom_flush_chars(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;

	if (isicom_paranoia_check(port, tty->name, "isicom_flush_chars"))
		return;

	if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
			!port->port.xmit_buf)
		return;

	/* this tells the transmitter to consider this port for
	   data output to the card ... that's the best we can do. */
	port->status |= ISI_TXOK;
}

/* write_room et all */
static int isicom_write_room(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;
	int free;

	if (isicom_paranoia_check(port, tty->name, "isicom_write_room"))
		return 0;

	free = SERIAL_XMIT_SIZE - port->xmit_cnt - 1;
	if (free < 0)
		free = 0;
	return free;
}

/* chars_in_buffer et all */
static int isicom_chars_in_buffer(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;
	if (isicom_paranoia_check(port, tty->name, "isicom_chars_in_buffer"))
		return 0;
	return port->xmit_cnt;
}

/* ioctl et all */
static int isicom_send_break(struct tty_struct *tty, int length)
{
	struct isi_port *port = tty->driver_data;
	struct isi_board *card = port->card;
	unsigned long base = card->base;

	if (length == -1)
		return -EOPNOTSUPP;

	if (!lock_card(card))
		return -EINVAL;

	outw(0x8000 | ((port->channel) << (card->shift_count)) | 0x3, base);
	outw((length & 0xff) << 8 | 0x00, base);
	outw((length & 0xff00u), base);
	InterruptTheCard(base);

	unlock_card(card);
	return 0;
}

static int isicom_tiocmget(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;
	/* just send the port status */
	u16 status = port->status;

	if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))
		return -ENODEV;

	return  ((status & ISI_RTS) ? TIOCM_RTS : 0) |
		((status & ISI_DTR) ? TIOCM_DTR : 0) |
		((status & ISI_DCD) ? TIOCM_CAR : 0) |
		((status & ISI_DSR) ? TIOCM_DSR : 0) |
		((status & ISI_CTS) ? TIOCM_CTS : 0) |
		((status & ISI_RI ) ? TIOCM_RI  : 0);
}

static int isicom_tiocmset(struct tty_struct *tty,
					unsigned int set, unsigned int clear)
{
	struct isi_port *port = tty->driver_data;
	unsigned long flags;

	if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))
		return -ENODEV;

	spin_lock_irqsave(&port->card->card_lock, flags);
	if (set & TIOCM_RTS)
		raise_rts(port);
	if (set & TIOCM_DTR)
		raise_dtr(port);

	if (clear & TIOCM_RTS)
		drop_rts(port);
	if (clear & TIOCM_DTR)
		drop_dtr(port);
	spin_unlock_irqrestore(&port->card->card_lock, flags);

	return 0;
}

static int isicom_set_serial_info(struct tty_struct *tty,
					struct serial_struct __user *info)
{
	struct isi_port *port = tty->driver_data;
	struct serial_struct newinfo;
	int reconfig_port;

	if (copy_from_user(&newinfo, info, sizeof(newinfo)))
		return -EFAULT;

	mutex_lock(&port->port.mutex);
	reconfig_port = ((port->port.flags & ASYNC_SPD_MASK) !=
		(newinfo.flags & ASYNC_SPD_MASK));

	if (!capable(CAP_SYS_ADMIN)) {
		if ((newinfo.close_delay != port->port.close_delay) ||
				(newinfo.closing_wait != port->port.closing_wait) ||
				((newinfo.flags & ~ASYNC_USR_MASK) !=
				(port->port.flags & ~ASYNC_USR_MASK))) {
			mutex_unlock(&port->port.mutex);
			return -EPERM;
		}
		port->port.flags = ((port->port.flags & ~ASYNC_USR_MASK) |
				(newinfo.flags & ASYNC_USR_MASK));
	} else {
		port->port.close_delay = newinfo.close_delay;
		port->port.closing_wait = newinfo.closing_wait;
		port->port.flags = ((port->port.flags & ~ASYNC_FLAGS) |
				(newinfo.flags & ASYNC_FLAGS));
	}
	if (reconfig_port) {
		unsigned long flags;
		spin_lock_irqsave(&port->card->card_lock, flags);
		isicom_config_port(tty);
		spin_unlock_irqrestore(&port->card->card_lock, flags);
	}
	mutex_unlock(&port->port.mutex);
	return 0;
}

static int isicom_get_serial_info(struct isi_port *port,
	struct serial_struct __user *info)
{
	struct serial_struct out_info;

	mutex_lock(&port->port.mutex);
	memset(&out_info, 0, sizeof(out_info));
/*	out_info.type = ? */
	out_info.line = port - isi_ports;
	out_info.port = port->card->base;
	out_info.irq = port->card->irq;
	out_info.flags = port->port.flags;
/*	out_info.baud_base = ? */
	out_info.close_delay = port->port.close_delay;
	out_info.closing_wait = port->port.closing_wait;
	mutex_unlock(&port->port.mutex);
	if (copy_to_user(info, &out_info, sizeof(out_info)))
		return -EFAULT;
	return 0;
}

static int isicom_ioctl(struct tty_struct *tty,
	unsigned int cmd, unsigned long arg)
{
	struct isi_port *port = tty->driver_data;
	void __user *argp = (void __user *)arg;

	if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))
		return -ENODEV;

	switch (cmd) {
	case TIOCGSERIAL:
		return isicom_get_serial_info(port, argp);

	case TIOCSSERIAL:
		return isicom_set_serial_info(tty, argp);

	default:
		return -ENOIOCTLCMD;
	}
	return 0;
}

/* set_termios et all */
static void isicom_set_termios(struct tty_struct *tty,
	struct ktermios *old_termios)
{
	struct isi_port *port = tty->driver_data;
	unsigned long flags;

	if (isicom_paranoia_check(port, tty->name, "isicom_set_termios"))
		return;

	if (tty->termios.c_cflag == old_termios->c_cflag &&
			tty->termios.c_iflag == old_termios->c_iflag)
		return;

	spin_lock_irqsave(&port->card->card_lock, flags);
	isicom_config_port(tty);
	spin_unlock_irqrestore(&port->card->card_lock, flags);

	if ((old_termios->c_cflag & CRTSCTS) && !C_CRTSCTS(tty)) {
		tty->hw_stopped = 0;
		isicom_start(tty);
	}
}

/* throttle et all */
static void isicom_throttle(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;
	struct isi_board *card = port->card;

	if (isicom_paranoia_check(port, tty->name, "isicom_throttle"))
		return;

	/* tell the card that this port cannot handle any more data for now */
	card->port_status &= ~(1 << port->channel);
	outw(card->port_status, card->base + 0x02);
}

/* unthrottle et all */
static void isicom_unthrottle(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;
	struct isi_board *card = port->card;

	if (isicom_paranoia_check(port, tty->name, "isicom_unthrottle"))
		return;

	/* tell the card that this port is ready to accept more data */
	card->port_status |= (1 << port->channel);
	outw(card->port_status, card->base + 0x02);
}

/* stop et all */
static void isicom_stop(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;

	if (isicom_paranoia_check(port, tty->name, "isicom_stop"))
		return;

	/* this tells the transmitter not to consider this port for
	   data output to the card. */
	port->status &= ~ISI_TXOK;
}

/* start et all */
static void isicom_start(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;

	if (isicom_paranoia_check(port, tty->name, "isicom_start"))
		return;

	/* this tells the transmitter to consider this port for
	   data output to the card. */
	port->status |= ISI_TXOK;
}

static void isicom_hangup(struct tty_struct *tty)
{
	struct isi_port *port = tty->driver_data;

	if (isicom_paranoia_check(port, tty->name, "isicom_hangup"))
		return;
	tty_port_hangup(&port->port);
}


/*
 * Driver init and deinit functions
 */

static const struct tty_operations isicom_ops = {
	.open			= isicom_open,
	.close			= isicom_close,
	.write			= isicom_write,
	.put_char		= isicom_put_char,
	.flush_chars		= isicom_flush_chars,
	.write_room		= isicom_write_room,
	.chars_in_buffer	= isicom_chars_in_buffer,
	.ioctl			= isicom_ioctl,
	.set_termios		= isicom_set_termios,
	.throttle		= isicom_throttle,
	.unthrottle		= isicom_unthrottle,
	.stop			= isicom_stop,
	.start			= isicom_start,
	.hangup			= isicom_hangup,
	.flush_buffer		= isicom_flush_buffer,
	.tiocmget		= isicom_tiocmget,
	.tiocmset		= isicom_tiocmset,
	.break_ctl		= isicom_send_break,
};

static const struct tty_port_operations isicom_port_ops = {
	.carrier_raised		= isicom_carrier_raised,
	.dtr_rts		= isicom_dtr_rts,
	.activate		= isicom_activate,
	.shutdown		= isicom_shutdown,
};

static int reset_card(struct pci_dev *pdev,
	const unsigned int card, unsigned int *signature)
{
	struct isi_board *board = pci_get_drvdata(pdev);
	unsigned long base = board->base;
	unsigned int sig, portcount = 0;
	int retval = 0;

	dev_dbg(&pdev->dev, "ISILoad:Resetting Card%d at 0x%lx\n", card + 1,
		base);

	inw(base + 0x8);

	msleep(10);

	outw(0, base + 0x8); /* Reset */

	msleep(1000);

	sig = inw(base + 0x4) & 0xff;

	if (sig != 0xa5 && sig != 0xbb && sig != 0xcc && sig != 0xdd &&
			sig != 0xee) {
		dev_warn(&pdev->dev, "ISILoad:Card%u reset failure (Possible "
			"bad I/O Port Address 0x%lx).\n", card + 1, base);
		dev_dbg(&pdev->dev, "Sig=0x%x\n", sig);
		retval = -EIO;
		goto end;
	}

	msleep(10);

	portcount = inw(base + 0x2);
	if (!(inw(base + 0xe) & 0x1) || (portcount != 0 && portcount != 4 &&
				portcount != 8 && portcount != 16)) {
		dev_err(&pdev->dev, "ISILoad:PCI Card%d reset failure.\n",
			card + 1);
		retval = -EIO;
		goto end;
	}

	switch (sig) {
	case 0xa5:
	case 0xbb:
	case 0xdd:
		board->port_count = (portcount == 4) ? 4 : 8;
		board->shift_count = 12;
		break;
	case 0xcc:
	case 0xee:
		board->port_count = 16;
		board->shift_count = 11;
		break;
	}
	dev_info(&pdev->dev, "-Done\n");
	*signature = sig;

end:
	return retval;
}

static int load_firmware(struct pci_dev *pdev,
	const unsigned int index, const unsigned int signature)
{
	struct isi_board *board = pci_get_drvdata(pdev);
	const struct firmware *fw;
	unsigned long base = board->base;
	unsigned int a;
	u16 word_count, status;
	int retval = -EIO;
	char *name;
	u8 *data;

	struct stframe {
		u16	addr;
		u16	count;
		u8	data[0];
	} *frame;

	switch (signature) {
	case 0xa5:
		name = "isi608.bin";
		break;
	case 0xbb:
		name = "isi608em.bin";
		break;
	case 0xcc:
		name = "isi616em.bin";
		break;
	case 0xdd:
		name = "isi4608.bin";
		break;
	case 0xee:
		name = "isi4616.bin";
		break;
	default:
		dev_err(&pdev->dev, "Unknown signature.\n");
		goto end;
	}

	retval = request_firmware(&fw, name, &pdev->dev);
	if (retval)
		goto end;

	retval = -EIO;

	for (frame = (struct stframe *)fw->data;
			frame < (struct stframe *)(fw->data + fw->size);
			frame = (struct stframe *)((u8 *)(frame + 1) +
				frame->count)) {
		if (WaitTillCardIsFree(base))
			goto errrelfw;

		outw(0xf0, base);	/* start upload sequence */
		outw(0x00, base);
		outw(frame->addr, base); /* lsb of address */

		word_count = frame->count / 2 + frame->count % 2;
		outw(word_count, base);
		InterruptTheCard(base);

		udelay(100); /* 0x2f */

		if (WaitTillCardIsFree(base))
			goto errrelfw;

		status = inw(base + 0x4);
		if (status != 0) {
			dev_warn(&pdev->dev, "Card%d rejected load header:\n"
				 "Address:0x%x\n"
				 "Count:0x%x\n"
				 "Status:0x%x\n",
				 index + 1, frame->addr, frame->count, status);
			goto errrelfw;
		}
		outsw(base, frame->data, word_count);

		InterruptTheCard(base);

		udelay(50); /* 0x0f */

		if (WaitTillCardIsFree(base))
			goto errrelfw;

		status = inw(base + 0x4);
		if (status != 0) {
			dev_err(&pdev->dev, "Card%d got out of sync.Card "
				"Status:0x%x\n", index + 1, status);
			goto errrelfw;
		}
	}

/* XXX: should we test it by reading it back and comparing with original like
 * in load firmware package? */
	for (frame = (struct stframe *)fw->data;
			frame < (struct stframe *)(fw->data + fw->size);
			frame = (struct stframe *)((u8 *)(frame + 1) +
				frame->count)) {
		if (WaitTillCardIsFree(base))
			goto errrelfw;

		outw(0xf1, base); /* start download sequence */
		outw(0x00, base);
		outw(frame->addr, base); /* lsb of address */

		word_count = (frame->count >> 1) + frame->count % 2;
		outw(word_count + 1, base);
		InterruptTheCard(base);

		udelay(50); /* 0xf */

		if (WaitTillCardIsFree(base))
			goto errrelfw;

		status = inw(base + 0x4);
		if (status != 0) {
			dev_warn(&pdev->dev, "Card%d rejected verify header:\n"
				 "Address:0x%x\n"
				 "Count:0x%x\n"
				 "Status: 0x%x\n",
				 index + 1, frame->addr, frame->count, status);
			goto errrelfw;
		}

		data = kmalloc(word_count * 2, GFP_KERNEL);
		if (data == NULL) {
			dev_err(&pdev->dev, "Card%d, firmware upload "
				"failed, not enough memory\n", index + 1);
			goto errrelfw;
		}
		inw(base);
		insw(base, data, word_count);
		InterruptTheCard(base);

		for (a = 0; a < frame->count; a++)
			if (data[a] != frame->data[a]) {
				kfree(data);
				dev_err(&pdev->dev, "Card%d, firmware upload "
					"failed\n", index + 1);
				goto errrelfw;
			}
		kfree(data);

		udelay(50); /* 0xf */

		if (WaitTillCardIsFree(base))
			goto errrelfw;

		status = inw(base + 0x4);
		if (status != 0) {
			dev_err(&pdev->dev, "Card%d verify got out of sync. "
				"Card Status:0x%x\n", index + 1, status);
			goto errrelfw;
		}
	}

	/* xfer ctrl */
	if (WaitTillCardIsFree(base))
		goto errrelfw;

	outw(0xf2, base);
	outw(0x800, base);
	outw(0x0, base);
	outw(0x0, base);
	InterruptTheCard(base);
	outw(0x0, base + 0x4); /* for ISI4608 cards */

	board->status |= FIRMWARE_LOADED;
	retval = 0;

errrelfw:
	release_firmware(fw);
end:
	return retval;
}

/*
 *	Insmod can set static symbols so keep these static
 */
static unsigned int card_count;

static int isicom_probe(struct pci_dev *pdev,
	const struct pci_device_id *ent)
{
	unsigned int uninitialized_var(signature), index;
	int retval = -EPERM;
	struct isi_board *board = NULL;

	if (card_count >= BOARD_COUNT)
		goto err;

	retval = pci_enable_device(pdev);
	if (retval) {
		dev_err(&pdev->dev, "failed to enable\n");
		goto err;
	}

	dev_info(&pdev->dev, "ISI PCI Card(Device ID 0x%x)\n", ent->device);

	/* allot the first empty slot in the array */
	for (index = 0; index < BOARD_COUNT; index++) {
		if (isi_card[index].base == 0) {
			board = &isi_card[index];
			break;
		}
	}
	if (index == BOARD_COUNT) {
		retval = -ENODEV;
		goto err_disable;
	}

	board->index = index;
	board->base = pci_resource_start(pdev, 3);
	board->irq = pdev->irq;
	card_count++;

	pci_set_drvdata(pdev, board);

	retval = pci_request_region(pdev, 3, ISICOM_NAME);
	if (retval) {
		dev_err(&pdev->dev, "I/O Region 0x%lx-0x%lx is busy. Card%d "
			"will be disabled.\n", board->base, board->base + 15,
			index + 1);
		retval = -EBUSY;
		goto errdec;
	}

	retval = request_irq(board->irq, isicom_interrupt,
			IRQF_SHARED, ISICOM_NAME, board);
	if (retval < 0) {
		dev_err(&pdev->dev, "Could not install handler at Irq %d. "
			"Card%d will be disabled.\n", board->irq, index + 1);
		goto errunrr;
	}

	retval = reset_card(pdev, index, &signature);
	if (retval < 0)
		goto errunri;

	retval = load_firmware(pdev, index, signature);
	if (retval < 0)
		goto errunri;

	for (index = 0; index < board->port_count; index++) {
		struct tty_port *tport = &board->ports[index].port;
		tty_port_init(tport);
		tport->ops = &isicom_port_ops;
		tport->close_delay = 50 * HZ/100;
		tport->closing_wait = 3000 * HZ/100;
		tty_port_register_device(tport, isicom_normal,
				board->index * 16 + index, &pdev->dev);
	}

	return 0;

errunri:
	free_irq(board->irq, board);
errunrr:
	pci_release_region(pdev, 3);
errdec:
	board->base = 0;
	card_count--;
err_disable:
	pci_disable_device(pdev);
err:
	return retval;
}

static void isicom_remove(struct pci_dev *pdev)
{
	struct isi_board *board = pci_get_drvdata(pdev);
	unsigned int i;

	for (i = 0; i < board->port_count; i++) {
		tty_unregister_device(isicom_normal, board->index * 16 + i);
		tty_port_destroy(&board->ports[i].port);
	}

	free_irq(board->irq, board);
	pci_release_region(pdev, 3);
	board->base = 0;
	card_count--;
	pci_disable_device(pdev);
}

static int __init isicom_init(void)
{
	int retval, idx, channel;
	struct isi_port *port;

	for (idx = 0; idx < BOARD_COUNT; idx++) {
		port = &isi_ports[idx * 16];
		isi_card[idx].ports = port;
		spin_lock_init(&isi_card[idx].card_lock);
		for (channel = 0; channel < 16; channel++, port++) {
			port->magic = ISICOM_MAGIC;
			port->card = &isi_card[idx];
			port->channel = channel;
			port->status = 0;
			/*  . . .  */
		}
		isi_card[idx].base = 0;
		isi_card[idx].irq = 0;
	}

	/* tty driver structure initialization */
	isicom_normal = alloc_tty_driver(PORT_COUNT);
	if (!isicom_normal) {
		retval = -ENOMEM;
		goto error;
	}

	isicom_normal->name 			= "ttyM";
	isicom_normal->major			= ISICOM_NMAJOR;
	isicom_normal->minor_start		= 0;
	isicom_normal->type			= TTY_DRIVER_TYPE_SERIAL;
	isicom_normal->subtype			= SERIAL_TYPE_NORMAL;
	isicom_normal->init_termios		= tty_std_termios;
	isicom_normal->init_termios.c_cflag	= B9600 | CS8 | CREAD | HUPCL |
		CLOCAL;
	isicom_normal->flags			= TTY_DRIVER_REAL_RAW |
		TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_HARDWARE_BREAK;
	tty_set_operations(isicom_normal, &isicom_ops);

	retval = tty_register_driver(isicom_normal);
	if (retval) {
		pr_debug("Couldn't register the dialin driver\n");
		goto err_puttty;
	}

	retval = pci_register_driver(&isicom_driver);
	if (retval < 0) {
		pr_err("Unable to register pci driver.\n");
		goto err_unrtty;
	}

	mod_timer(&tx, jiffies + 1);

	return 0;
err_unrtty:
	tty_unregister_driver(isicom_normal);
err_puttty:
	put_tty_driver(isicom_normal);
error:
	return retval;
}

static void __exit isicom_exit(void)
{
	del_timer_sync(&tx);

	pci_unregister_driver(&isicom_driver);
	tty_unregister_driver(isicom_normal);
	put_tty_driver(isicom_normal);
}

module_init(isicom_init);
module_exit(isicom_exit);

MODULE_AUTHOR("MultiTech");
MODULE_DESCRIPTION("Driver for the ISI series of cards by MultiTech");
MODULE_LICENSE("GPL");
MODULE_FIRMWARE("isi608.bin");
MODULE_FIRMWARE("isi608em.bin");
MODULE_FIRMWARE("isi616em.bin");
MODULE_FIRMWARE("isi4608.bin");
MODULE_FIRMWARE("isi4616.bin");