Free Electrons

Embedded Linux Experts

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
/*
 * Serial driver for the amiga builtin port.
 *
 * This code was created by taking serial.c version 4.30 from kernel
 * release 2.3.22, replacing all hardware related stuff with the
 * corresponding amiga hardware actions, and removing all irrelevant
 * code. As a consequence, it uses many of the constants and names
 * associated with the registers and bits of 16550 compatible UARTS -
 * but only to keep track of status, etc in the state variables. It
 * was done this was to make it easier to keep the code in line with
 * (non hardware specific) changes to serial.c.
 *
 * The port is registered with the tty driver as minor device 64, and
 * therefore other ports should should only use 65 upwards.
 *
 * Richard Lucock 28/12/99
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 
 * 		1998, 1999  Theodore Ts'o
 *
 */

/*
 * Serial driver configuration section.  Here are the various options:
 *
 * SERIAL_PARANOIA_CHECK
 * 		Check the magic number for the async_structure where
 * 		ever possible.
 */

#include <linux/delay.h>

#undef SERIAL_PARANOIA_CHECK
#define SERIAL_DO_RESTART

/* Set of debugging defines */

#undef SERIAL_DEBUG_INTR
#undef SERIAL_DEBUG_OPEN
#undef SERIAL_DEBUG_FLOW
#undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT

/* Sanity checks */

#if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
#define DBG_CNT(s) printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n", \
 tty->name, (info->tport.flags), serial_driver->refcount,info->count,tty->count,s)
#else
#define DBG_CNT(s)
#endif

/*
 * End of serial driver configuration section.
 */

#include <linux/module.h>

#include <linux/types.h>
#include <linux/serial.h>
#include <linux/serial_reg.h>
static char *serial_version = "4.30";

#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/circ_buf.h>
#include <linux/console.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/platform_device.h>

#include <asm/setup.h>


#include <asm/irq.h>

#include <asm/amigahw.h>
#include <asm/amigaints.h>

struct serial_state {
	struct tty_port		tport;
	struct circ_buf		xmit;
	struct async_icount	icount;

	unsigned long		port;
	int			baud_base;
	int			xmit_fifo_size;
	int			custom_divisor;
	int			read_status_mask;
	int			ignore_status_mask;
	int			timeout;
	int			quot;
	int			IER; 	/* Interrupt Enable Register */
	int			MCR; 	/* Modem control register */
	int			x_char;	/* xon/xoff character */
};

#define custom amiga_custom
static char *serial_name = "Amiga-builtin serial driver";

static struct tty_driver *serial_driver;

/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256

static unsigned char current_ctl_bits;

static void change_speed(struct tty_struct *tty, struct serial_state *info,
		struct ktermios *old);
static void rs_wait_until_sent(struct tty_struct *tty, int timeout);


static struct serial_state rs_table[1];

#define NR_PORTS ARRAY_SIZE(rs_table)

#include <asm/uaccess.h>

#define serial_isroot()	(capable(CAP_SYS_ADMIN))


static inline int serial_paranoia_check(struct serial_state *info,
					char *name, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
	static const char *badmagic =
		"Warning: bad magic number for serial struct (%s) in %s\n";
	static const char *badinfo =
		"Warning: null async_struct for (%s) in %s\n";

	if (!info) {
		printk(badinfo, name, routine);
		return 1;
	}
	if (info->magic != SERIAL_MAGIC) {
		printk(badmagic, name, routine);
		return 1;
	}
#endif
	return 0;
}

/* some serial hardware definitions */
#define SDR_OVRUN   (1<<15)
#define SDR_RBF     (1<<14)
#define SDR_TBE     (1<<13)
#define SDR_TSRE    (1<<12)

#define SERPER_PARENB    (1<<15)

#define AC_SETCLR   (1<<15)
#define AC_UARTBRK  (1<<11)

#define SER_DTR     (1<<7)
#define SER_RTS     (1<<6)
#define SER_DCD     (1<<5)
#define SER_CTS     (1<<4)
#define SER_DSR     (1<<3)

static __inline__ void rtsdtr_ctrl(int bits)
{
    ciab.pra = ((bits & (SER_RTS | SER_DTR)) ^ (SER_RTS | SER_DTR)) | (ciab.pra & ~(SER_RTS | SER_DTR));
}

/*
 * ------------------------------------------------------------
 * rs_stop() and rs_start()
 *
 * This routines are called before setting or resetting tty->stopped.
 * They enable or disable transmitter interrupts, as necessary.
 * ------------------------------------------------------------
 */
static void rs_stop(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_stop"))
		return;

	local_irq_save(flags);
	if (info->IER & UART_IER_THRI) {
		info->IER &= ~UART_IER_THRI;
		/* disable Tx interrupt and remove any pending interrupts */
		custom.intena = IF_TBE;
		mb();
		custom.intreq = IF_TBE;
		mb();
	}
	local_irq_restore(flags);
}

static void rs_start(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_start"))
		return;

	local_irq_save(flags);
	if (info->xmit.head != info->xmit.tail
	    && info->xmit.buf
	    && !(info->IER & UART_IER_THRI)) {
		info->IER |= UART_IER_THRI;
		custom.intena = IF_SETCLR | IF_TBE;
		mb();
		/* set a pending Tx Interrupt, transmitter should restart now */
		custom.intreq = IF_SETCLR | IF_TBE;
		mb();
	}
	local_irq_restore(flags);
}

/*
 * ----------------------------------------------------------------------
 *
 * Here starts the interrupt handling routines.  All of the following
 * subroutines are declared as inline and are folded into
 * rs_interrupt().  They were separated out for readability's sake.
 *
 * Note: rs_interrupt() is a "fast" interrupt, which means that it
 * runs with interrupts turned off.  People who may want to modify
 * rs_interrupt() should try to keep the interrupt handler as fast as
 * possible.  After you are done making modifications, it is not a bad
 * idea to do:
 * 
 * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
 *
 * and look at the resulting assemble code in serial.s.
 *
 * 				- Ted Ts'o (tytso@mit.edu), 7-Mar-93
 * -----------------------------------------------------------------------
 */

static void receive_chars(struct serial_state *info)
{
        int status;
	int serdatr;
	unsigned char ch, flag;
	struct	async_icount *icount;
	int oe = 0;

	icount = &info->icount;

	status = UART_LSR_DR; /* We obviously have a character! */
	serdatr = custom.serdatr;
	mb();
	custom.intreq = IF_RBF;
	mb();

	if((serdatr & 0x1ff) == 0)
	    status |= UART_LSR_BI;
	if(serdatr & SDR_OVRUN)
	    status |= UART_LSR_OE;

	ch = serdatr & 0xff;
	icount->rx++;

#ifdef SERIAL_DEBUG_INTR
	printk("DR%02x:%02x...", ch, status);
#endif
	flag = TTY_NORMAL;

	/*
	 * We don't handle parity or frame errors - but I have left
	 * the code in, since I'm not sure that the errors can't be
	 * detected.
	 */

	if (status & (UART_LSR_BI | UART_LSR_PE |
		      UART_LSR_FE | UART_LSR_OE)) {
	  /*
	   * For statistics only
	   */
	  if (status & UART_LSR_BI) {
	    status &= ~(UART_LSR_FE | UART_LSR_PE);
	    icount->brk++;
	  } else if (status & UART_LSR_PE)
	    icount->parity++;
	  else if (status & UART_LSR_FE)
	    icount->frame++;
	  if (status & UART_LSR_OE)
	    icount->overrun++;

	  /*
	   * Now check to see if character should be
	   * ignored, and mask off conditions which
	   * should be ignored.
	   */
	  if (status & info->ignore_status_mask)
	    goto out;

	  status &= info->read_status_mask;

	  if (status & (UART_LSR_BI)) {
#ifdef SERIAL_DEBUG_INTR
	    printk("handling break....");
#endif
	    flag = TTY_BREAK;
	    if (info->tport.flags & ASYNC_SAK)
	      do_SAK(info->tport.tty);
	  } else if (status & UART_LSR_PE)
	    flag = TTY_PARITY;
	  else if (status & UART_LSR_FE)
	    flag = TTY_FRAME;
	  if (status & UART_LSR_OE) {
	    /*
	     * Overrun is special, since it's
	     * reported immediately, and doesn't
	     * affect the current character
	     */
	     oe = 1;
	  }
	}
	tty_insert_flip_char(&info->tport, ch, flag);
	if (oe == 1)
		tty_insert_flip_char(&info->tport, 0, TTY_OVERRUN);
	tty_flip_buffer_push(&info->tport);
out:
	return;
}

static void transmit_chars(struct serial_state *info)
{
	custom.intreq = IF_TBE;
	mb();
	if (info->x_char) {
	        custom.serdat = info->x_char | 0x100;
		mb();
		info->icount.tx++;
		info->x_char = 0;
		return;
	}
	if (info->xmit.head == info->xmit.tail
	    || info->tport.tty->stopped
	    || info->tport.tty->hw_stopped) {
		info->IER &= ~UART_IER_THRI;
	        custom.intena = IF_TBE;
		mb();
		return;
	}

	custom.serdat = info->xmit.buf[info->xmit.tail++] | 0x100;
	mb();
	info->xmit.tail = info->xmit.tail & (SERIAL_XMIT_SIZE-1);
	info->icount.tx++;

	if (CIRC_CNT(info->xmit.head,
		     info->xmit.tail,
		     SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
		tty_wakeup(info->tport.tty);

#ifdef SERIAL_DEBUG_INTR
	printk("THRE...");
#endif
	if (info->xmit.head == info->xmit.tail) {
	        custom.intena = IF_TBE;
		mb();
		info->IER &= ~UART_IER_THRI;
	}
}

static void check_modem_status(struct serial_state *info)
{
	struct tty_port *port = &info->tport;
	unsigned char status = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);
	unsigned char dstatus;
	struct	async_icount *icount;

	/* Determine bits that have changed */
	dstatus = status ^ current_ctl_bits;
	current_ctl_bits = status;

	if (dstatus) {
		icount = &info->icount;
		/* update input line counters */
		if (dstatus & SER_DSR)
			icount->dsr++;
		if (dstatus & SER_DCD) {
			icount->dcd++;
		}
		if (dstatus & SER_CTS)
			icount->cts++;
		wake_up_interruptible(&port->delta_msr_wait);
	}

	if ((port->flags & ASYNC_CHECK_CD) && (dstatus & SER_DCD)) {
#if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
		printk("ttyS%d CD now %s...", info->line,
		       (!(status & SER_DCD)) ? "on" : "off");
#endif
		if (!(status & SER_DCD))
			wake_up_interruptible(&port->open_wait);
		else {
#ifdef SERIAL_DEBUG_OPEN
			printk("doing serial hangup...");
#endif
			if (port->tty)
				tty_hangup(port->tty);
		}
	}
	if (tty_port_cts_enabled(port)) {
		if (port->tty->hw_stopped) {
			if (!(status & SER_CTS)) {
#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
				printk("CTS tx start...");
#endif
				port->tty->hw_stopped = 0;
				info->IER |= UART_IER_THRI;
				custom.intena = IF_SETCLR | IF_TBE;
				mb();
				/* set a pending Tx Interrupt, transmitter should restart now */
				custom.intreq = IF_SETCLR | IF_TBE;
				mb();
				tty_wakeup(port->tty);
				return;
			}
		} else {
			if ((status & SER_CTS)) {
#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
				printk("CTS tx stop...");
#endif
				port->tty->hw_stopped = 1;
				info->IER &= ~UART_IER_THRI;
				/* disable Tx interrupt and remove any pending interrupts */
				custom.intena = IF_TBE;
				mb();
				custom.intreq = IF_TBE;
				mb();
			}
		}
	}
}

static irqreturn_t ser_vbl_int( int irq, void *data)
{
        /* vbl is just a periodic interrupt we tie into to update modem status */
	struct serial_state *info = data;
	/*
	 * TBD - is it better to unregister from this interrupt or to
	 * ignore it if MSI is clear ?
	 */
	if(info->IER & UART_IER_MSI)
	  check_modem_status(info);
	return IRQ_HANDLED;
}

static irqreturn_t ser_rx_int(int irq, void *dev_id)
{
	struct serial_state *info = dev_id;

#ifdef SERIAL_DEBUG_INTR
	printk("ser_rx_int...");
#endif

	if (!info->tport.tty)
		return IRQ_NONE;

	receive_chars(info);
#ifdef SERIAL_DEBUG_INTR
	printk("end.\n");
#endif
	return IRQ_HANDLED;
}

static irqreturn_t ser_tx_int(int irq, void *dev_id)
{
	struct serial_state *info = dev_id;

	if (custom.serdatr & SDR_TBE) {
#ifdef SERIAL_DEBUG_INTR
	  printk("ser_tx_int...");
#endif

	  if (!info->tport.tty)
		return IRQ_NONE;

	  transmit_chars(info);
#ifdef SERIAL_DEBUG_INTR
	  printk("end.\n");
#endif
	}
	return IRQ_HANDLED;
}

/*
 * -------------------------------------------------------------------
 * Here ends the serial interrupt routines.
 * -------------------------------------------------------------------
 */

/*
 * ---------------------------------------------------------------
 * Low level utility subroutines for the serial driver:  routines to
 * figure out the appropriate timeout for an interrupt chain, routines
 * to initialize and startup a serial port, and routines to shutdown a
 * serial port.  Useful stuff like that.
 * ---------------------------------------------------------------
 */

static int startup(struct tty_struct *tty, struct serial_state *info)
{
	struct tty_port *port = &info->tport;
	unsigned long flags;
	int	retval=0;
	unsigned long page;

	page = get_zeroed_page(GFP_KERNEL);
	if (!page)
		return -ENOMEM;

	local_irq_save(flags);

	if (port->flags & ASYNC_INITIALIZED) {
		free_page(page);
		goto errout;
	}

	if (info->xmit.buf)
		free_page(page);
	else
		info->xmit.buf = (unsigned char *) page;

#ifdef SERIAL_DEBUG_OPEN
	printk("starting up ttys%d ...", info->line);
#endif

	/* Clear anything in the input buffer */

	custom.intreq = IF_RBF;
	mb();

	retval = request_irq(IRQ_AMIGA_VERTB, ser_vbl_int, 0, "serial status", info);
	if (retval) {
	  if (serial_isroot()) {
	      set_bit(TTY_IO_ERROR, &tty->flags);
	    retval = 0;
	  }
	  goto errout;
	}

	/* enable both Rx and Tx interrupts */
	custom.intena = IF_SETCLR | IF_RBF | IF_TBE;
	mb();
	info->IER = UART_IER_MSI;

	/* remember current state of the DCD and CTS bits */
	current_ctl_bits = ciab.pra & (SER_DCD | SER_CTS | SER_DSR);

	info->MCR = 0;
	if (C_BAUD(tty))
	  info->MCR = SER_DTR | SER_RTS;
	rtsdtr_ctrl(info->MCR);

	clear_bit(TTY_IO_ERROR, &tty->flags);
	info->xmit.head = info->xmit.tail = 0;

	/*
	 * Set up the tty->alt_speed kludge
	 */
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
		tty->alt_speed = 57600;
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
		tty->alt_speed = 115200;
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
		tty->alt_speed = 230400;
	if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
		tty->alt_speed = 460800;

	/*
	 * and set the speed of the serial port
	 */
	change_speed(tty, info, NULL);

	port->flags |= ASYNC_INITIALIZED;
	local_irq_restore(flags);
	return 0;

errout:
	local_irq_restore(flags);
	return retval;
}

/*
 * This routine will shutdown a serial port; interrupts are disabled, and
 * DTR is dropped if the hangup on close termio flag is on.
 */
static void shutdown(struct tty_struct *tty, struct serial_state *info)
{
	unsigned long	flags;
	struct serial_state *state;

	if (!(info->tport.flags & ASYNC_INITIALIZED))
		return;

	state = info;

#ifdef SERIAL_DEBUG_OPEN
	printk("Shutting down serial port %d ....\n", info->line);
#endif

	local_irq_save(flags); /* Disable interrupts */

	/*
	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
	 * here so the queue might never be waken up
	 */
	wake_up_interruptible(&info->tport.delta_msr_wait);

	/*
	 * Free the IRQ, if necessary
	 */
	free_irq(IRQ_AMIGA_VERTB, info);

	if (info->xmit.buf) {
		free_page((unsigned long) info->xmit.buf);
		info->xmit.buf = NULL;
	}

	info->IER = 0;
	custom.intena = IF_RBF | IF_TBE;
	mb();

	/* disable break condition */
	custom.adkcon = AC_UARTBRK;
	mb();

	if (tty->termios.c_cflag & HUPCL)
		info->MCR &= ~(SER_DTR|SER_RTS);
	rtsdtr_ctrl(info->MCR);

	set_bit(TTY_IO_ERROR, &tty->flags);

	info->tport.flags &= ~ASYNC_INITIALIZED;
	local_irq_restore(flags);
}


/*
 * This routine is called to set the UART divisor registers to match
 * the specified baud rate for a serial port.
 */
static void change_speed(struct tty_struct *tty, struct serial_state *info,
			 struct ktermios *old_termios)
{
	struct tty_port *port = &info->tport;
	int	quot = 0, baud_base, baud;
	unsigned cflag, cval = 0;
	int	bits;
	unsigned long	flags;

	cflag = tty->termios.c_cflag;

	/* Byte size is always 8 bits plus parity bit if requested */

	cval = 3; bits = 10;
	if (cflag & CSTOPB) {
		cval |= 0x04;
		bits++;
	}
	if (cflag & PARENB) {
		cval |= UART_LCR_PARITY;
		bits++;
	}
	if (!(cflag & PARODD))
		cval |= UART_LCR_EPAR;
#ifdef CMSPAR
	if (cflag & CMSPAR)
		cval |= UART_LCR_SPAR;
#endif

	/* Determine divisor based on baud rate */
	baud = tty_get_baud_rate(tty);
	if (!baud)
		baud = 9600;	/* B0 transition handled in rs_set_termios */
	baud_base = info->baud_base;
	if (baud == 38400 && (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
		quot = info->custom_divisor;
	else {
		if (baud == 134)
			/* Special case since 134 is really 134.5 */
			quot = (2*baud_base / 269);
		else if (baud)
			quot = baud_base / baud;
	}
	/* If the quotient is zero refuse the change */
	if (!quot && old_termios) {
		/* FIXME: Will need updating for new tty in the end */
		tty->termios.c_cflag &= ~CBAUD;
		tty->termios.c_cflag |= (old_termios->c_cflag & CBAUD);
		baud = tty_get_baud_rate(tty);
		if (!baud)
			baud = 9600;
		if (baud == 38400 &&
		    (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
			quot = info->custom_divisor;
		else {
			if (baud == 134)
				/* Special case since 134 is really 134.5 */
				quot = (2*baud_base / 269);
			else if (baud)
				quot = baud_base / baud;
		}
	}
	/* As a last resort, if the quotient is zero, default to 9600 bps */
	if (!quot)
		quot = baud_base / 9600;
	info->quot = quot;
	info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
	info->timeout += HZ/50;		/* Add .02 seconds of slop */

	/* CTS flow control flag and modem status interrupts */
	info->IER &= ~UART_IER_MSI;
	if (port->flags & ASYNC_HARDPPS_CD)
		info->IER |= UART_IER_MSI;
	if (cflag & CRTSCTS) {
		port->flags |= ASYNC_CTS_FLOW;
		info->IER |= UART_IER_MSI;
	} else
		port->flags &= ~ASYNC_CTS_FLOW;
	if (cflag & CLOCAL)
		port->flags &= ~ASYNC_CHECK_CD;
	else {
		port->flags |= ASYNC_CHECK_CD;
		info->IER |= UART_IER_MSI;
	}
	/* TBD:
	 * Does clearing IER_MSI imply that we should disable the VBL interrupt ?
	 */

	/*
	 * Set up parity check flag
	 */

	info->read_status_mask = UART_LSR_OE | UART_LSR_DR;
	if (I_INPCK(tty))
		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
	if (I_BRKINT(tty) || I_PARMRK(tty))
		info->read_status_mask |= UART_LSR_BI;

	/*
	 * Characters to ignore
	 */
	info->ignore_status_mask = 0;
	if (I_IGNPAR(tty))
		info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
	if (I_IGNBRK(tty)) {
		info->ignore_status_mask |= UART_LSR_BI;
		/*
		 * If we're ignore parity and break indicators, ignore 
		 * overruns too.  (For real raw support).
		 */
		if (I_IGNPAR(tty))
			info->ignore_status_mask |= UART_LSR_OE;
	}
	/*
	 * !!! ignore all characters if CREAD is not set
	 */
	if ((cflag & CREAD) == 0)
		info->ignore_status_mask |= UART_LSR_DR;
	local_irq_save(flags);

	{
	  short serper;

	/* Set up the baud rate */
	  serper = quot - 1;

	/* Enable or disable parity bit */

	if(cval & UART_LCR_PARITY)
	  serper |= (SERPER_PARENB);

	custom.serper = serper;
	mb();
	}

	local_irq_restore(flags);
}

static int rs_put_char(struct tty_struct *tty, unsigned char ch)
{
	struct serial_state *info;
	unsigned long flags;

	info = tty->driver_data;

	if (serial_paranoia_check(info, tty->name, "rs_put_char"))
		return 0;

	if (!info->xmit.buf)
		return 0;

	local_irq_save(flags);
	if (CIRC_SPACE(info->xmit.head,
		       info->xmit.tail,
		       SERIAL_XMIT_SIZE) == 0) {
		local_irq_restore(flags);
		return 0;
	}

	info->xmit.buf[info->xmit.head++] = ch;
	info->xmit.head &= SERIAL_XMIT_SIZE-1;
	local_irq_restore(flags);
	return 1;
}

static void rs_flush_chars(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_flush_chars"))
		return;

	if (info->xmit.head == info->xmit.tail
	    || tty->stopped
	    || tty->hw_stopped
	    || !info->xmit.buf)
		return;

	local_irq_save(flags);
	info->IER |= UART_IER_THRI;
	custom.intena = IF_SETCLR | IF_TBE;
	mb();
	/* set a pending Tx Interrupt, transmitter should restart now */
	custom.intreq = IF_SETCLR | IF_TBE;
	mb();
	local_irq_restore(flags);
}

static int rs_write(struct tty_struct * tty, const unsigned char *buf, int count)
{
	int	c, ret = 0;
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_write"))
		return 0;

	if (!info->xmit.buf)
		return 0;

	local_irq_save(flags);
	while (1) {
		c = CIRC_SPACE_TO_END(info->xmit.head,
				      info->xmit.tail,
				      SERIAL_XMIT_SIZE);
		if (count < c)
			c = count;
		if (c <= 0) {
			break;
		}
		memcpy(info->xmit.buf + info->xmit.head, buf, c);
		info->xmit.head = ((info->xmit.head + c) &
				   (SERIAL_XMIT_SIZE-1));
		buf += c;
		count -= c;
		ret += c;
	}
	local_irq_restore(flags);

	if (info->xmit.head != info->xmit.tail
	    && !tty->stopped
	    && !tty->hw_stopped
	    && !(info->IER & UART_IER_THRI)) {
		info->IER |= UART_IER_THRI;
		local_irq_disable();
		custom.intena = IF_SETCLR | IF_TBE;
		mb();
		/* set a pending Tx Interrupt, transmitter should restart now */
		custom.intreq = IF_SETCLR | IF_TBE;
		mb();
		local_irq_restore(flags);
	}
	return ret;
}

static int rs_write_room(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;

	if (serial_paranoia_check(info, tty->name, "rs_write_room"))
		return 0;
	return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}

static int rs_chars_in_buffer(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;

	if (serial_paranoia_check(info, tty->name, "rs_chars_in_buffer"))
		return 0;
	return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}

static void rs_flush_buffer(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_flush_buffer"))
		return;
	local_irq_save(flags);
	info->xmit.head = info->xmit.tail = 0;
	local_irq_restore(flags);
	tty_wakeup(tty);
}

/*
 * This function is used to send a high-priority XON/XOFF character to
 * the device
 */
static void rs_send_xchar(struct tty_struct *tty, char ch)
{
	struct serial_state *info = tty->driver_data;
        unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_send_char"))
		return;

	info->x_char = ch;
	if (ch) {
		/* Make sure transmit interrupts are on */

	        /* Check this ! */
	        local_irq_save(flags);
		if(!(custom.intenar & IF_TBE)) {
		    custom.intena = IF_SETCLR | IF_TBE;
		    mb();
		    /* set a pending Tx Interrupt, transmitter should restart now */
		    custom.intreq = IF_SETCLR | IF_TBE;
		    mb();
		}
		local_irq_restore(flags);

		info->IER |= UART_IER_THRI;
	}
}

/*
 * ------------------------------------------------------------
 * rs_throttle()
 * 
 * This routine is called by the upper-layer tty layer to signal that
 * incoming characters should be throttled.
 * ------------------------------------------------------------
 */
static void rs_throttle(struct tty_struct * tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;
#ifdef SERIAL_DEBUG_THROTTLE
	char	buf[64];

	printk("throttle %s: %d....\n", tty_name(tty, buf),
	       tty->ldisc.chars_in_buffer(tty));
#endif

	if (serial_paranoia_check(info, tty->name, "rs_throttle"))
		return;

	if (I_IXOFF(tty))
		rs_send_xchar(tty, STOP_CHAR(tty));

	if (tty->termios.c_cflag & CRTSCTS)
		info->MCR &= ~SER_RTS;

	local_irq_save(flags);
	rtsdtr_ctrl(info->MCR);
	local_irq_restore(flags);
}

static void rs_unthrottle(struct tty_struct * tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;
#ifdef SERIAL_DEBUG_THROTTLE
	char	buf[64];

	printk("unthrottle %s: %d....\n", tty_name(tty, buf),
	       tty->ldisc.chars_in_buffer(tty));
#endif

	if (serial_paranoia_check(info, tty->name, "rs_unthrottle"))
		return;

	if (I_IXOFF(tty)) {
		if (info->x_char)
			info->x_char = 0;
		else
			rs_send_xchar(tty, START_CHAR(tty));
	}
	if (tty->termios.c_cflag & CRTSCTS)
		info->MCR |= SER_RTS;
	local_irq_save(flags);
	rtsdtr_ctrl(info->MCR);
	local_irq_restore(flags);
}

/*
 * ------------------------------------------------------------
 * rs_ioctl() and friends
 * ------------------------------------------------------------
 */

static int get_serial_info(struct tty_struct *tty, struct serial_state *state,
			   struct serial_struct __user * retinfo)
{
	struct serial_struct tmp;
   
	if (!retinfo)
		return -EFAULT;
	memset(&tmp, 0, sizeof(tmp));
	tty_lock(tty);
	tmp.line = tty->index;
	tmp.port = state->port;
	tmp.flags = state->tport.flags;
	tmp.xmit_fifo_size = state->xmit_fifo_size;
	tmp.baud_base = state->baud_base;
	tmp.close_delay = state->tport.close_delay;
	tmp.closing_wait = state->tport.closing_wait;
	tmp.custom_divisor = state->custom_divisor;
	tty_unlock(tty);
	if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
		return -EFAULT;
	return 0;
}

static int set_serial_info(struct tty_struct *tty, struct serial_state *state,
			   struct serial_struct __user * new_info)
{
	struct tty_port *port = &state->tport;
	struct serial_struct new_serial;
	bool change_spd;
	int 			retval = 0;

	if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
		return -EFAULT;

	tty_lock(tty);
	change_spd = ((new_serial.flags ^ port->flags) & ASYNC_SPD_MASK) ||
		new_serial.custom_divisor != state->custom_divisor;
	if (new_serial.irq || new_serial.port != state->port ||
			new_serial.xmit_fifo_size != state->xmit_fifo_size) {
		tty_unlock(tty);
		return -EINVAL;
	}
  
	if (!serial_isroot()) {
		if ((new_serial.baud_base != state->baud_base) ||
		    (new_serial.close_delay != port->close_delay) ||
		    (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
		    ((new_serial.flags & ~ASYNC_USR_MASK) !=
		     (port->flags & ~ASYNC_USR_MASK))) {
			tty_unlock(tty);
			return -EPERM;
		}
		port->flags = ((port->flags & ~ASYNC_USR_MASK) |
			       (new_serial.flags & ASYNC_USR_MASK));
		state->custom_divisor = new_serial.custom_divisor;
		goto check_and_exit;
	}

	if (new_serial.baud_base < 9600) {
		tty_unlock(tty);
		return -EINVAL;
	}

	/*
	 * OK, past this point, all the error checking has been done.
	 * At this point, we start making changes.....
	 */

	state->baud_base = new_serial.baud_base;
	port->flags = ((port->flags & ~ASYNC_FLAGS) |
			(new_serial.flags & ASYNC_FLAGS));
	state->custom_divisor = new_serial.custom_divisor;
	port->close_delay = new_serial.close_delay * HZ/100;
	port->closing_wait = new_serial.closing_wait * HZ/100;
	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;

check_and_exit:
	if (port->flags & ASYNC_INITIALIZED) {
		if (change_spd) {
			if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
				tty->alt_speed = 57600;
			if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
				tty->alt_speed = 115200;
			if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
				tty->alt_speed = 230400;
			if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
				tty->alt_speed = 460800;
			change_speed(tty, state, NULL);
		}
	} else
		retval = startup(tty, state);
	tty_unlock(tty);
	return retval;
}


/*
 * get_lsr_info - get line status register info
 *
 * Purpose: Let user call ioctl() to get info when the UART physically
 * 	    is emptied.  On bus types like RS485, the transmitter must
 * 	    release the bus after transmitting. This must be done when
 * 	    the transmit shift register is empty, not be done when the
 * 	    transmit holding register is empty.  This functionality
 * 	    allows an RS485 driver to be written in user space. 
 */
static int get_lsr_info(struct serial_state *info, unsigned int __user *value)
{
	unsigned char status;
	unsigned int result;
	unsigned long flags;

	local_irq_save(flags);
	status = custom.serdatr;
	mb();
	local_irq_restore(flags);
	result = ((status & SDR_TSRE) ? TIOCSER_TEMT : 0);
	if (copy_to_user(value, &result, sizeof(int)))
		return -EFAULT;
	return 0;
}


static int rs_tiocmget(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;
	unsigned char control, status;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
		return -ENODEV;
	if (tty->flags & (1 << TTY_IO_ERROR))
		return -EIO;

	control = info->MCR;
	local_irq_save(flags);
	status = ciab.pra;
	local_irq_restore(flags);
	return    ((control & SER_RTS) ? TIOCM_RTS : 0)
		| ((control & SER_DTR) ? TIOCM_DTR : 0)
		| (!(status  & SER_DCD) ? TIOCM_CAR : 0)
		| (!(status  & SER_DSR) ? TIOCM_DSR : 0)
		| (!(status  & SER_CTS) ? TIOCM_CTS : 0);
}

static int rs_tiocmset(struct tty_struct *tty, unsigned int set,
						unsigned int clear)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
		return -ENODEV;
	if (tty->flags & (1 << TTY_IO_ERROR))
		return -EIO;

	local_irq_save(flags);
	if (set & TIOCM_RTS)
		info->MCR |= SER_RTS;
	if (set & TIOCM_DTR)
		info->MCR |= SER_DTR;
	if (clear & TIOCM_RTS)
		info->MCR &= ~SER_RTS;
	if (clear & TIOCM_DTR)
		info->MCR &= ~SER_DTR;
	rtsdtr_ctrl(info->MCR);
	local_irq_restore(flags);
	return 0;
}

/*
 * rs_break() --- routine which turns the break handling on or off
 */
static int rs_break(struct tty_struct *tty, int break_state)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->name, "rs_break"))
		return -EINVAL;

	local_irq_save(flags);
	if (break_state == -1)
	  custom.adkcon = AC_SETCLR | AC_UARTBRK;
	else
	  custom.adkcon = AC_UARTBRK;
	mb();
	local_irq_restore(flags);
	return 0;
}

/*
 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
 * Return: write counters to the user passed counter struct
 * NB: both 1->0 and 0->1 transitions are counted except for
 *     RI where only 0->1 is counted.
 */
static int rs_get_icount(struct tty_struct *tty,
				struct serial_icounter_struct *icount)
{
	struct serial_state *info = tty->driver_data;
	struct async_icount cnow;
	unsigned long flags;

	local_irq_save(flags);
	cnow = info->icount;
	local_irq_restore(flags);
	icount->cts = cnow.cts;
	icount->dsr = cnow.dsr;
	icount->rng = cnow.rng;
	icount->dcd = cnow.dcd;
	icount->rx = cnow.rx;
	icount->tx = cnow.tx;
	icount->frame = cnow.frame;
	icount->overrun = cnow.overrun;
	icount->parity = cnow.parity;
	icount->brk = cnow.brk;
	icount->buf_overrun = cnow.buf_overrun;

	return 0;
}

static int rs_ioctl(struct tty_struct *tty,
		    unsigned int cmd, unsigned long arg)
{
	struct serial_state *info = tty->driver_data;
	struct async_icount cprev, cnow;	/* kernel counter temps */
	void __user *argp = (void __user *)arg;
	unsigned long flags;
	DEFINE_WAIT(wait);
	int ret;

	if (serial_paranoia_check(info, tty->name, "rs_ioctl"))
		return -ENODEV;

	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
		if (tty->flags & (1 << TTY_IO_ERROR))
		    return -EIO;
	}

	switch (cmd) {
		case TIOCGSERIAL:
			return get_serial_info(tty, info, argp);
		case TIOCSSERIAL:
			return set_serial_info(tty, info, argp);
		case TIOCSERCONFIG:
			return 0;

		case TIOCSERGETLSR: /* Get line status register */
			return get_lsr_info(info, argp);

		case TIOCSERGSTRUCT:
			if (copy_to_user(argp,
					 info, sizeof(struct serial_state)))
				return -EFAULT;
			return 0;

		/*
		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
		 * - mask passed in arg for lines of interest
 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
		 * Caller should use TIOCGICOUNT to see which one it was
		 */
		case TIOCMIWAIT:
			local_irq_save(flags);
			/* note the counters on entry */
			cprev = info->icount;
			local_irq_restore(flags);
			while (1) {
				prepare_to_wait(&info->tport.delta_msr_wait,
						&wait, TASK_INTERRUPTIBLE);
				local_irq_save(flags);
				cnow = info->icount; /* atomic copy */
				local_irq_restore(flags);
				if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && 
				    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
					ret = -EIO; /* no change => error */
					break;
				}
				if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
				     ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
				     ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
				     ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
					ret = 0;
					break;
				}
				schedule();
				/* see if a signal did it */
				if (signal_pending(current)) {
					ret = -ERESTARTSYS;
					break;
				}
				cprev = cnow;
			}
			finish_wait(&info->tport.delta_msr_wait, &wait);
			return ret;

		case TIOCSERGWILD:
		case TIOCSERSWILD:
			/* "setserial -W" is called in Debian boot */
			printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
			return 0;

		default:
			return -ENOIOCTLCMD;
		}
	return 0;
}

static void rs_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
{
	struct serial_state *info = tty->driver_data;
	unsigned long flags;
	unsigned int cflag = tty->termios.c_cflag;

	change_speed(tty, info, old_termios);

	/* Handle transition to B0 status */
	if ((old_termios->c_cflag & CBAUD) &&
	    !(cflag & CBAUD)) {
		info->MCR &= ~(SER_DTR|SER_RTS);
		local_irq_save(flags);
		rtsdtr_ctrl(info->MCR);
		local_irq_restore(flags);
	}

	/* Handle transition away from B0 status */
	if (!(old_termios->c_cflag & CBAUD) &&
	    (cflag & CBAUD)) {
		info->MCR |= SER_DTR;
		if (!(tty->termios.c_cflag & CRTSCTS) || 
		    !test_bit(TTY_THROTTLED, &tty->flags)) {
			info->MCR |= SER_RTS;
		}
		local_irq_save(flags);
		rtsdtr_ctrl(info->MCR);
		local_irq_restore(flags);
	}

	/* Handle turning off CRTSCTS */
	if ((old_termios->c_cflag & CRTSCTS) &&
	    !(tty->termios.c_cflag & CRTSCTS)) {
		tty->hw_stopped = 0;
		rs_start(tty);
	}

#if 0
	/*
	 * No need to wake up processes in open wait, since they
	 * sample the CLOCAL flag once, and don't recheck it.
	 * XXX  It's not clear whether the current behavior is correct
	 * or not.  Hence, this may change.....
	 */
	if (!(old_termios->c_cflag & CLOCAL) &&
	    (tty->termios.c_cflag & CLOCAL))
		wake_up_interruptible(&info->open_wait);
#endif
}

/*
 * ------------------------------------------------------------
 * rs_close()
 * 
 * This routine is called when the serial port gets closed.  First, we
 * wait for the last remaining data to be sent.  Then, we unlink its
 * async structure from the interrupt chain if necessary, and we free
 * that IRQ if nothing is left in the chain.
 * ------------------------------------------------------------
 */
static void rs_close(struct tty_struct *tty, struct file * filp)
{
	struct serial_state *state = tty->driver_data;
	struct tty_port *port = &state->tport;

	if (serial_paranoia_check(state, tty->name, "rs_close"))
		return;

	if (tty_port_close_start(port, tty, filp) == 0)
		return;

	/*
	 * At this point we stop accepting input.  To do this, we
	 * disable the receive line status interrupts, and tell the
	 * interrupt driver to stop checking the data ready bit in the
	 * line status register.
	 */
	state->read_status_mask &= ~UART_LSR_DR;
	if (port->flags & ASYNC_INITIALIZED) {
	        /* disable receive interrupts */
	        custom.intena = IF_RBF;
		mb();
		/* clear any pending receive interrupt */
		custom.intreq = IF_RBF;
		mb();

		/*
		 * Before we drop DTR, make sure the UART transmitter
		 * has completely drained; this is especially
		 * important if there is a transmit FIFO!
		 */
		rs_wait_until_sent(tty, state->timeout);
	}
	shutdown(tty, state);
	rs_flush_buffer(tty);
		
	tty_ldisc_flush(tty);
	port->tty = NULL;

	tty_port_close_end(port, tty);
}

/*
 * rs_wait_until_sent() --- wait until the transmitter is empty
 */
static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
{
	struct serial_state *info = tty->driver_data;
	unsigned long orig_jiffies, char_time;
	int lsr;

	if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
		return;

	if (info->xmit_fifo_size == 0)
		return; /* Just in case.... */

	orig_jiffies = jiffies;

	/*
	 * Set the check interval to be 1/5 of the estimated time to
	 * send a single character, and make it at least 1.  The check
	 * interval should also be less than the timeout.
	 * 
	 * Note: we have to use pretty tight timings here to satisfy
	 * the NIST-PCTS.
	 */
	char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
	char_time = char_time / 5;
	if (char_time == 0)
		char_time = 1;
	if (timeout)
	  char_time = min_t(unsigned long, char_time, timeout);
	/*
	 * If the transmitter hasn't cleared in twice the approximate
	 * amount of time to send the entire FIFO, it probably won't
	 * ever clear.  This assumes the UART isn't doing flow
	 * control, which is currently the case.  Hence, if it ever
	 * takes longer than info->timeout, this is probably due to a
	 * UART bug of some kind.  So, we clamp the timeout parameter at
	 * 2*info->timeout.
	 */
	if (!timeout || timeout > 2*info->timeout)
		timeout = 2*info->timeout;
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
	printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
	printk("jiff=%lu...", jiffies);
#endif
	while(!((lsr = custom.serdatr) & SDR_TSRE)) {
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
		printk("serdatr = %d (jiff=%lu)...", lsr, jiffies);
#endif
		msleep_interruptible(jiffies_to_msecs(char_time));
		if (signal_pending(current))
			break;
		if (timeout && time_after(jiffies, orig_jiffies + timeout))
			break;
	}
	__set_current_state(TASK_RUNNING);

#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
	printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
#endif
}

/*
 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
static void rs_hangup(struct tty_struct *tty)
{
	struct serial_state *info = tty->driver_data;

	if (serial_paranoia_check(info, tty->name, "rs_hangup"))
		return;

	rs_flush_buffer(tty);
	shutdown(tty, info);
	info->tport.count = 0;
	info->tport.flags &= ~ASYNC_NORMAL_ACTIVE;
	info->tport.tty = NULL;
	wake_up_interruptible(&info->tport.open_wait);
}

/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its async structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
static int rs_open(struct tty_struct *tty, struct file * filp)
{
	struct serial_state *info = rs_table + tty->index;
	struct tty_port *port = &info->tport;
	int retval;

	port->count++;
	port->tty = tty;
	tty->driver_data = info;
	tty->port = port;
	if (serial_paranoia_check(info, tty->name, "rs_open"))
		return -ENODEV;

	port->low_latency = (port->flags & ASYNC_LOW_LATENCY) ? 1 : 0;

	retval = startup(tty, info);
	if (retval) {
		return retval;
	}

	return tty_port_block_til_ready(port, tty, filp);
}

/*
 * /proc fs routines....
 */

static inline void line_info(struct seq_file *m, int line,
		struct serial_state *state)
{
	char	stat_buf[30], control, status;
	unsigned long flags;

	seq_printf(m, "%d: uart:amiga_builtin", line);

	local_irq_save(flags);
	status = ciab.pra;
	control = (state->tport.flags & ASYNC_INITIALIZED) ? state->MCR : status;
	local_irq_restore(flags);

	stat_buf[0] = 0;
	stat_buf[1] = 0;
	if(!(control & SER_RTS))
		strcat(stat_buf, "|RTS");
	if(!(status & SER_CTS))
		strcat(stat_buf, "|CTS");
	if(!(control & SER_DTR))
		strcat(stat_buf, "|DTR");
	if(!(status & SER_DSR))
		strcat(stat_buf, "|DSR");
	if(!(status & SER_DCD))
		strcat(stat_buf, "|CD");

	if (state->quot)
		seq_printf(m, " baud:%d", state->baud_base / state->quot);

	seq_printf(m, " tx:%d rx:%d", state->icount.tx, state->icount.rx);

	if (state->icount.frame)
		seq_printf(m, " fe:%d", state->icount.frame);

	if (state->icount.parity)
		seq_printf(m, " pe:%d", state->icount.parity);

	if (state->icount.brk)
		seq_printf(m, " brk:%d", state->icount.brk);

	if (state->icount.overrun)
		seq_printf(m, " oe:%d", state->icount.overrun);

	/*
	 * Last thing is the RS-232 status lines
	 */
	seq_printf(m, " %s\n", stat_buf+1);
}

static int rs_proc_show(struct seq_file *m, void *v)
{
	seq_printf(m, "serinfo:1.0 driver:%s\n", serial_version);
	line_info(m, 0, &rs_table[0]);
	return 0;
}

static int rs_proc_open(struct inode *inode, struct file *file)
{
	return single_open(file, rs_proc_show, NULL);
}

static const struct file_operations rs_proc_fops = {
	.owner		= THIS_MODULE,
	.open		= rs_proc_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

/*
 * ---------------------------------------------------------------------
 * rs_init() and friends
 *
 * rs_init() is called at boot-time to initialize the serial driver.
 * ---------------------------------------------------------------------
 */

/*
 * This routine prints out the appropriate serial driver version
 * number, and identifies which options were configured into this
 * driver.
 */
static void show_serial_version(void)
{
 	printk(KERN_INFO "%s version %s\n", serial_name, serial_version);
}


static const struct tty_operations serial_ops = {
	.open = rs_open,
	.close = rs_close,
	.write = rs_write,
	.put_char = rs_put_char,
	.flush_chars = rs_flush_chars,
	.write_room = rs_write_room,
	.chars_in_buffer = rs_chars_in_buffer,
	.flush_buffer = rs_flush_buffer,
	.ioctl = rs_ioctl,
	.throttle = rs_throttle,
	.unthrottle = rs_unthrottle,
	.set_termios = rs_set_termios,
	.stop = rs_stop,
	.start = rs_start,
	.hangup = rs_hangup,
	.break_ctl = rs_break,
	.send_xchar = rs_send_xchar,
	.wait_until_sent = rs_wait_until_sent,
	.tiocmget = rs_tiocmget,
	.tiocmset = rs_tiocmset,
	.get_icount = rs_get_icount,
	.proc_fops = &rs_proc_fops,
};

static int amiga_carrier_raised(struct tty_port *port)
{
	return !(ciab.pra & SER_DCD);
}

static void amiga_dtr_rts(struct tty_port *port, int raise)
{
	struct serial_state *info = container_of(port, struct serial_state,
			tport);
	unsigned long flags;

	if (raise)
		info->MCR |= SER_DTR|SER_RTS;
	else
		info->MCR &= ~(SER_DTR|SER_RTS);

	local_irq_save(flags);
	rtsdtr_ctrl(info->MCR);
	local_irq_restore(flags);
}

static const struct tty_port_operations amiga_port_ops = {
	.carrier_raised = amiga_carrier_raised,
	.dtr_rts = amiga_dtr_rts,
};

/*
 * The serial driver boot-time initialization code!
 */
static int __init amiga_serial_probe(struct platform_device *pdev)
{
	unsigned long flags;
	struct serial_state * state;
	int error;

	serial_driver = alloc_tty_driver(NR_PORTS);
	if (!serial_driver)
		return -ENOMEM;

	show_serial_version();

	/* Initialize the tty_driver structure */

	serial_driver->driver_name = "amiserial";
	serial_driver->name = "ttyS";
	serial_driver->major = TTY_MAJOR;
	serial_driver->minor_start = 64;
	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
	serial_driver->subtype = SERIAL_TYPE_NORMAL;
	serial_driver->init_termios = tty_std_termios;
	serial_driver->init_termios.c_cflag =
		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	serial_driver->flags = TTY_DRIVER_REAL_RAW;
	tty_set_operations(serial_driver, &serial_ops);

	state = rs_table;
	state->port = (int)&custom.serdatr; /* Just to give it a value */
	state->custom_divisor = 0;
	state->icount.cts = state->icount.dsr = 
	  state->icount.rng = state->icount.dcd = 0;
	state->icount.rx = state->icount.tx = 0;
	state->icount.frame = state->icount.parity = 0;
	state->icount.overrun = state->icount.brk = 0;
	tty_port_init(&state->tport);
	state->tport.ops = &amiga_port_ops;
	tty_port_link_device(&state->tport, serial_driver, 0);

	error = tty_register_driver(serial_driver);
	if (error)
		goto fail_put_tty_driver;

	printk(KERN_INFO "ttyS0 is the amiga builtin serial port\n");

	/* Hardware set up */

	state->baud_base = amiga_colorclock;
	state->xmit_fifo_size = 1;

	/* set ISRs, and then disable the rx interrupts */
	error = request_irq(IRQ_AMIGA_TBE, ser_tx_int, 0, "serial TX", state);
	if (error)
		goto fail_unregister;

	error = request_irq(IRQ_AMIGA_RBF, ser_rx_int, 0,
			    "serial RX", state);
	if (error)
		goto fail_free_irq;

	local_irq_save(flags);

	/* turn off Rx and Tx interrupts */
	custom.intena = IF_RBF | IF_TBE;
	mb();

	/* clear any pending interrupt */
	custom.intreq = IF_RBF | IF_TBE;
	mb();

	local_irq_restore(flags);

	/*
	 * set the appropriate directions for the modem control flags,
	 * and clear RTS and DTR
	 */
	ciab.ddra |= (SER_DTR | SER_RTS);   /* outputs */
	ciab.ddra &= ~(SER_DCD | SER_CTS | SER_DSR);  /* inputs */

	platform_set_drvdata(pdev, state);

	return 0;

fail_free_irq:
	free_irq(IRQ_AMIGA_TBE, state);
fail_unregister:
	tty_unregister_driver(serial_driver);
fail_put_tty_driver:
	tty_port_destroy(&state->tport);
	put_tty_driver(serial_driver);
	return error;
}

static int __exit amiga_serial_remove(struct platform_device *pdev)
{
	int error;
	struct serial_state *state = platform_get_drvdata(pdev);

	/* printk("Unloading %s: version %s\n", serial_name, serial_version); */
	if ((error = tty_unregister_driver(serial_driver)))
		printk("SERIAL: failed to unregister serial driver (%d)\n",
		       error);
	put_tty_driver(serial_driver);
	tty_port_destroy(&state->tport);

	free_irq(IRQ_AMIGA_TBE, state);
	free_irq(IRQ_AMIGA_RBF, state);

	return error;
}

static struct platform_driver amiga_serial_driver = {
	.remove = __exit_p(amiga_serial_remove),
	.driver   = {
		.name	= "amiga-serial",
		.owner	= THIS_MODULE,
	},
};

module_platform_driver_probe(amiga_serial_driver, amiga_serial_probe);


#if defined(CONFIG_SERIAL_CONSOLE) && !defined(MODULE)

/*
 * ------------------------------------------------------------
 * Serial console driver
 * ------------------------------------------------------------
 */

static void amiga_serial_putc(char c)
{
	custom.serdat = (unsigned char)c | 0x100;
	while (!(custom.serdatr & 0x2000))
		barrier();
}

/*
 *	Print a string to the serial port trying not to disturb
 *	any possible real use of the port...
 *
 *	The console must be locked when we get here.
 */
static void serial_console_write(struct console *co, const char *s,
				unsigned count)
{
	unsigned short intena = custom.intenar;

	custom.intena = IF_TBE;

	while (count--) {
		if (*s == '\n')
			amiga_serial_putc('\r');
		amiga_serial_putc(*s++);
	}

	custom.intena = IF_SETCLR | (intena & IF_TBE);
}

static struct tty_driver *serial_console_device(struct console *c, int *index)
{
	*index = 0;
	return serial_driver;
}

static struct console sercons = {
	.name =		"ttyS",
	.write =	serial_console_write,
	.device =	serial_console_device,
	.flags =	CON_PRINTBUFFER,
	.index =	-1,
};

/*
 *	Register console.
 */
static int __init amiserial_console_init(void)
{
	if (!MACH_IS_AMIGA)
		return -ENODEV;

	register_console(&sercons);
	return 0;
}
console_initcall(amiserial_console_init);

#endif /* CONFIG_SERIAL_CONSOLE && !MODULE */

MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:amiga-serial");