summaryrefslogtreecommitdiffstats
path: root/drivers/net/wan/cosa.c
blob: 087eb266601fc81f4b62ee95008a7b2ece8353a4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
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
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
/* $Id: cosa.c,v 1.31 2000/03/08 17:47:16 kas Exp $ */

/*
 *  Copyright (C) 1995-1997  Jan "Yenya" Kasprzak <kas@fi.muni.cz>
 *  Generic HDLC port Copyright (C) 2008 Krzysztof Halasa <khc@pm.waw.pl>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/*
 * The driver for the SRP and COSA synchronous serial cards.
 *
 * HARDWARE INFO
 *
 * Both cards are developed at the Institute of Computer Science,
 * Masaryk University (http://www.ics.muni.cz/). The hardware is
 * developed by Jiri Novotny <novotny@ics.muni.cz>. More information
 * and the photo of both cards is available at
 * http://www.pavoucek.cz/cosa.html. The card documentation, firmwares
 * and other goods can be downloaded from ftp://ftp.ics.muni.cz/pub/cosa/.
 * For Linux-specific utilities, see below in the "Software info" section.
 * If you want to order the card, contact Jiri Novotny.
 *
 * The SRP (serial port?, the Czech word "srp" means "sickle") card
 * is a 2-port intelligent (with its own 8-bit CPU) synchronous serial card
 * with V.24 interfaces up to 80kb/s each.
 *
 * The COSA (communication serial adapter?, the Czech word "kosa" means
 * "scythe") is a next-generation sync/async board with two interfaces
 * - currently any of V.24, X.21, V.35 and V.36 can be selected.
 * It has a 16-bit SAB80166 CPU and can do up to 10 Mb/s per channel.
 * The 8-channels version is in development.
 *
 * Both types have downloadable firmware and communicate via ISA DMA.
 * COSA can be also a bus-mastering device.
 *
 * SOFTWARE INFO
 *
 * The homepage of the Linux driver is at http://www.fi.muni.cz/~kas/cosa/.
 * The CVS tree of Linux driver can be viewed there, as well as the
 * firmware binaries and user-space utilities for downloading the firmware
 * into the card and setting up the card.
 *
 * The Linux driver (unlike the present *BSD drivers :-) can work even
 * for the COSA and SRP in one computer and allows each channel to work
 * in one of the two modes (character or network device).
 *
 * AUTHOR
 *
 * The Linux driver was written by Jan "Yenya" Kasprzak <kas@fi.muni.cz>.
 *
 * You can mail me bugfixes and even success reports. I am especially
 * interested in the SMP and/or muliti-channel success/failure reports
 * (I wonder if I did the locking properly :-).
 *
 * THE AUTHOR USED THE FOLLOWING SOURCES WHEN PROGRAMMING THE DRIVER
 *
 * The COSA/SRP NetBSD driver by Zdenek Salvet and Ivos Cernohlavek
 * The skeleton.c by Donald Becker
 * The SDL Riscom/N2 driver by Mike Natale
 * The Comtrol Hostess SV11 driver by Alan Cox
 * The Sync PPP/Cisco HDLC layer (syncppp.c) ported to Linux by Alan Cox
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/poll.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/hdlc.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/netdevice.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <asm/io.h>
#include <asm/dma.h>
#include <asm/byteorder.h>

#undef COSA_SLOW_IO	/* for testing purposes only */

#include "cosa.h"

/* Maximum length of the identification string. */
#define COSA_MAX_ID_STRING	128

/* Maximum length of the channel name */
#define COSA_MAX_NAME		(sizeof("cosaXXXcXXX")+1)

/* Per-channel data structure */

struct channel_data {
	int usage;	/* Usage count; >0 for chrdev, -1 for netdev */
	int num;	/* Number of the channel */
	struct cosa_data *cosa;	/* Pointer to the per-card structure */
	int txsize;	/* Size of transmitted data */
	char *txbuf;	/* Transmit buffer */
	char name[COSA_MAX_NAME];	/* channel name */

	/* The HW layer interface */
	/* routine called from the RX interrupt */
	char *(*setup_rx)(struct channel_data *channel, int size);
	/* routine called when the RX is done (from the EOT interrupt) */
	int (*rx_done)(struct channel_data *channel);
	/* routine called when the TX is done (from the EOT interrupt) */
	int (*tx_done)(struct channel_data *channel, int size);

	/* Character device parts */
	struct mutex rlock;
	struct semaphore wsem;
	char *rxdata;
	int rxsize;
	wait_queue_head_t txwaitq, rxwaitq;
	int tx_status, rx_status;

	/* generic HDLC device parts */
	struct net_device *netdev;
	struct sk_buff *rx_skb, *tx_skb;
};

/* cosa->firmware_status bits */
#define COSA_FW_RESET		(1<<0)	/* Is the ROM monitor active? */
#define COSA_FW_DOWNLOAD	(1<<1)	/* Is the microcode downloaded? */
#define COSA_FW_START		(1<<2)	/* Is the microcode running? */

struct cosa_data {
	int num;			/* Card number */
	char name[COSA_MAX_NAME];	/* Card name - e.g "cosa0" */
	unsigned int datareg, statusreg;	/* I/O ports */
	unsigned short irq, dma;	/* IRQ and DMA number */
	unsigned short startaddr;	/* Firmware start address */
	unsigned short busmaster;	/* Use busmastering? */
	int nchannels;			/* # of channels on this card */
	int driver_status;		/* For communicating with firmware */
	int firmware_status;		/* Downloaded, reseted, etc. */
	unsigned long rxbitmap, txbitmap;/* Bitmap of channels who are willing to send/receive data */
	unsigned long rxtx;		/* RX or TX in progress? */
	int enabled;
	int usage;				/* usage count */
	int txchan, txsize, rxsize;
	struct channel_data *rxchan;
	char *bouncebuf;
	char *txbuf, *rxbuf;
	struct channel_data *chan;
	spinlock_t lock;	/* For exclusive operations on this structure */
	char id_string[COSA_MAX_ID_STRING];	/* ROM monitor ID string */
	char *type;				/* card type */
};

/*
 * Define this if you want all the possible ports to be autoprobed.
 * It is here but it probably is not a good idea to use this.
 */
/* #define COSA_ISA_AUTOPROBE	1 */

/*
 * Character device major number. 117 was allocated for us.
 * The value of 0 means to allocate a first free one.
 */
static DEFINE_MUTEX(cosa_chardev_mutex);
static int cosa_major = 117;

/*
 * Encoding of the minor numbers:
 * The lowest CARD_MINOR_BITS bits means the channel on the single card,
 * the highest bits means the card number.
 */
#define CARD_MINOR_BITS	4	/* How many bits in minor number are reserved
				 * for the single card */
/*
 * The following depends on CARD_MINOR_BITS. Unfortunately, the "MODULE_STRING"
 * macro doesn't like anything other than the raw number as an argument :-(
 */
#define MAX_CARDS	16
/* #define MAX_CARDS	(1 << (8-CARD_MINOR_BITS)) */

#define DRIVER_RX_READY		0x0001
#define DRIVER_TX_READY		0x0002
#define DRIVER_TXMAP_SHIFT	2
#define DRIVER_TXMAP_MASK	0x0c	/* FIXME: 0xfc for 8-channel version */

/*
 * for cosa->rxtx - indicates whether either transmit or receive is
 * in progress. These values are mean number of the bit.
 */
#define TXBIT 0
#define RXBIT 1
#define IRQBIT 2

#define COSA_MTU 2000	/* FIXME: I don't know this exactly */

#undef DEBUG_DATA //1	/* Dump the data read or written to the channel */
#undef DEBUG_IRQS //1	/* Print the message when the IRQ is received */
#undef DEBUG_IO   //1	/* Dump the I/O traffic */

#define TX_TIMEOUT	(5*HZ)

/* Maybe the following should be allocated dynamically */
static struct cosa_data cosa_cards[MAX_CARDS];
static int nr_cards;

#ifdef COSA_ISA_AUTOPROBE
static int io[MAX_CARDS+1]  = { 0x220, 0x228, 0x210, 0x218, 0, };
/* NOTE: DMA is not autoprobed!!! */
static int dma[MAX_CARDS+1] = { 1, 7, 1, 7, 1, 7, 1, 7, 0, };
#else
static int io[MAX_CARDS+1];
static int dma[MAX_CARDS+1];
#endif
/* IRQ can be safely autoprobed */
static int irq[MAX_CARDS+1] = { -1, -1, -1, -1, -1, -1, 0, };

/* for class stuff*/
static struct class *cosa_class;

#ifdef MODULE
module_param_array(io, int, NULL, 0);
MODULE_PARM_DESC(io, "The I/O bases of the COSA or SRP cards");
module_param_array(irq, int, NULL, 0);
MODULE_PARM_DESC(irq, "The IRQ lines of the COSA or SRP cards");
module_param_array(dma, int, NULL, 0);
MODULE_PARM_DESC(dma, "The DMA channels of the COSA or SRP cards");

MODULE_AUTHOR("Jan \"Yenya\" Kasprzak, <kas@fi.muni.cz>");
MODULE_DESCRIPTION("Modular driver for the COSA or SRP synchronous card");
MODULE_LICENSE("GPL");
#endif

/* I use this mainly for testing purposes */
#ifdef COSA_SLOW_IO
#define cosa_outb outb_p
#define cosa_outw outw_p
#define cosa_inb  inb_p
#define cosa_inw  inw_p
#else
#define cosa_outb outb
#define cosa_outw outw
#define cosa_inb  inb
#define cosa_inw  inw
#endif

#define is_8bit(cosa)		(!(cosa->datareg & 0x08))

#define cosa_getstatus(cosa)	(cosa_inb(cosa->statusreg))
#define cosa_putstatus(cosa, stat)	(cosa_outb(stat, cosa->statusreg))
#define cosa_getdata16(cosa)	(cosa_inw(cosa->datareg))
#define cosa_getdata8(cosa)	(cosa_inb(cosa->datareg))
#define cosa_putdata16(cosa, dt)	(cosa_outw(dt, cosa->datareg))
#define cosa_putdata8(cosa, dt)	(cosa_outb(dt, cosa->datareg))

/* Initialization stuff */
static int cosa_probe(int ioaddr, int irq, int dma);

/* HW interface */
static void cosa_enable_rx(struct channel_data *chan);
static void cosa_disable_rx(struct channel_data *chan);
static int cosa_start_tx(struct channel_data *channel, char *buf, int size);
static void cosa_kick(struct cosa_data *cosa);
static int cosa_dma_able(struct channel_data *chan, char *buf, int data);

/* Network device stuff */
static int cosa_net_attach(struct net_device *dev, unsigned short encoding,
			   unsigned short parity);
static int cosa_net_open(struct net_device *d);
static int cosa_net_close(struct net_device *d);
static void cosa_net_timeout(struct net_device *d);
static netdev_tx_t cosa_net_tx(struct sk_buff *skb, struct net_device *d);
static char *cosa_net_setup_rx(struct channel_data *channel, int size);
static int cosa_net_rx_done(struct channel_data *channel);
static int cosa_net_tx_done(struct channel_data *channel, int size);
static int cosa_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);

/* Character device */
static char *chrdev_setup_rx(struct channel_data *channel, int size);
static int chrdev_rx_done(struct channel_data *channel);
static int chrdev_tx_done(struct channel_data *channel, int size);
static ssize_t cosa_read(struct file *file,
	char __user *buf, size_t count, loff_t *ppos);
static ssize_t cosa_write(struct file *file,
	const char __user *buf, size_t count, loff_t *ppos);
static unsigned int cosa_poll(struct file *file, poll_table *poll);
static int cosa_open(struct inode *inode, struct file *file);
static int cosa_release(struct inode *inode, struct file *file);
static long cosa_chardev_ioctl(struct file *file, unsigned int cmd,
				unsigned long arg);
#ifdef COSA_FASYNC_WORKING
static int cosa_fasync(struct inode *inode, struct file *file, int on);
#endif

static const struct file_operations cosa_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.read		= cosa_read,
	.write		= cosa_write,
	.poll		= cosa_poll,
	.unlocked_ioctl	= cosa_chardev_ioctl,
	.open		= cosa_open,
	.release	= cosa_release,
#ifdef COSA_FASYNC_WORKING
	.fasync		= cosa_fasync,
#endif
};

/* Ioctls */
static int cosa_start(struct cosa_data *cosa, int address);
static int cosa_reset(struct cosa_data *cosa);
static int cosa_download(struct cosa_data *cosa, void __user *a);
static int cosa_readmem(struct cosa_data *cosa, void __user *a);

/* COSA/SRP ROM monitor */
static int download(struct cosa_data *cosa, const char __user *data, int addr, int len);
static int startmicrocode(struct cosa_data *cosa, int address);
static int readmem(struct cosa_data *cosa, char __user *data, int addr, int len);
static int cosa_reset_and_read_id(struct cosa_data *cosa, char *id);

/* Auxiliary functions */
static int get_wait_data(struct cosa_data *cosa);
static int put_wait_data(struct cosa_data *cosa, int data);
static int puthexnumber(struct cosa_data *cosa, int number);
static void put_driver_status(struct cosa_data *cosa);
static void put_driver_status_nolock(struct cosa_data *cosa);

/* Interrupt handling */
static irqreturn_t cosa_interrupt(int irq, void *cosa);

/* I/O ops debugging */
#ifdef DEBUG_IO
static void debug_data_in(struct cosa_data *cosa, int data);
static void debug_data_out(struct cosa_data *cosa, int data);
static void debug_data_cmd(struct cosa_data *cosa, int data);
static void debug_status_in(struct cosa_data *cosa, int status);
static void debug_status_out(struct cosa_data *cosa, int status);
#endif

static inline struct channel_data* dev_to_chan(struct net_device *dev)
{
	return (struct channel_data *)dev_to_hdlc(dev)->priv;
}

/* ---------- Initialization stuff ---------- */

static int __init cosa_init(void)
{
	int i, err = 0;

	if (cosa_major > 0) {
		if (register_chrdev(cosa_major, "cosa", &cosa_fops)) {
			pr_warn("unable to get major %d\n", cosa_major);
			err = -EIO;
			goto out;
		}
	} else {
		if (!(cosa_major=register_chrdev(0, "cosa", &cosa_fops))) {
			pr_warn("unable to register chardev\n");
			err = -EIO;
			goto out;
		}
	}
	for (i=0; i<MAX_CARDS; i++)
		cosa_cards[i].num = -1;
	for (i=0; io[i] != 0 && i < MAX_CARDS; i++)
		cosa_probe(io[i], irq[i], dma[i]);
	if (!nr_cards) {
		pr_warn("no devices found\n");
		unregister_chrdev(cosa_major, "cosa");
		err = -ENODEV;
		goto out;
	}
	cosa_class = class_create(THIS_MODULE, "cosa");
	if (IS_ERR(cosa_class)) {
		err = PTR_ERR(cosa_class);
		goto out_chrdev;
	}
	for (i = 0; i < nr_cards; i++)
		device_create(cosa_class, NULL, MKDEV(cosa_major, i), NULL,
			      "cosa%d", i);
	err = 0;
	goto out;

out_chrdev:
	unregister_chrdev(cosa_major, "cosa");
out:
	return err;
}
module_init(cosa_init);

static void __exit cosa_exit(void)
{
	struct cosa_data *cosa;
	int i;

	for (i = 0; i < nr_cards; i++)
		device_destroy(cosa_class, MKDEV(cosa_major, i));
	class_destroy(cosa_class);

	for (cosa = cosa_cards; nr_cards--; cosa++) {
		/* Clean up the per-channel data */
		for (i = 0; i < cosa->nchannels; i++) {
			/* Chardev driver has no alloc'd per-channel data */
			unregister_hdlc_device(cosa->chan[i].netdev);
			free_netdev(cosa->chan[i].netdev);
		}
		/* Clean up the per-card data */
		kfree(cosa->chan);
		kfree(cosa->bouncebuf);
		free_irq(cosa->irq, cosa);
		free_dma(cosa->dma);
		release_region(cosa->datareg, is_8bit(cosa) ? 2 : 4);
	}
	unregister_chrdev(cosa_major, "cosa");
}
module_exit(cosa_exit);

static const struct net_device_ops cosa_ops = {
	.ndo_open       = cosa_net_open,
	.ndo_stop       = cosa_net_close,
	.ndo_start_xmit = hdlc_start_xmit,
	.ndo_do_ioctl   = cosa_net_ioctl,
	.ndo_tx_timeout = cosa_net_timeout,
};

static int cosa_probe(int base, int irq, int dma)
{
	struct cosa_data *cosa = cosa_cards+nr_cards;
	int i, err = 0;

	memset(cosa, 0, sizeof(struct cosa_data));

	/* Checking validity of parameters: */
	/* IRQ should be 2-7 or 10-15; negative IRQ means autoprobe */
	if ((irq >= 0  && irq < 2) || irq > 15 || (irq < 10 && irq > 7)) {
		pr_info("invalid IRQ %d\n", irq);
		return -1;
	}
	/* I/O address should be between 0x100 and 0x3ff and should be
	 * multiple of 8. */
	if (base < 0x100 || base > 0x3ff || base & 0x7) {
		pr_info("invalid I/O address 0x%x\n", base);
		return -1;
	}
	/* DMA should be 0,1 or 3-7 */
	if (dma < 0 || dma == 4 || dma > 7) {
		pr_info("invalid DMA %d\n", dma);
		return -1;
	}
	/* and finally, on 16-bit COSA DMA should be 4-7 and 
	 * I/O base should not be multiple of 0x10 */
	if (((base & 0x8) && dma < 4) || (!(base & 0x8) && dma > 3)) {
		pr_info("8/16 bit base and DMA mismatch (base=0x%x, dma=%d)\n",
			base, dma);
		return -1;
	}

	cosa->dma = dma;
	cosa->datareg = base;
	cosa->statusreg = is_8bit(cosa)?base+1:base+2;
	spin_lock_init(&cosa->lock);

	if (!request_region(base, is_8bit(cosa)?2:4,"cosa"))
		return -1;
	
	if (cosa_reset_and_read_id(cosa, cosa->id_string) < 0) {
		printk(KERN_DEBUG "probe at 0x%x failed.\n", base);
		err = -1;
		goto err_out;
	}

	/* Test the validity of identification string */
	if (!strncmp(cosa->id_string, "SRP", 3))
		cosa->type = "srp";
	else if (!strncmp(cosa->id_string, "COSA", 4))
		cosa->type = is_8bit(cosa)? "cosa8": "cosa16";
	else {
/* Print a warning only if we are not autoprobing */
#ifndef COSA_ISA_AUTOPROBE
		pr_info("valid signature not found at 0x%x\n", base);
#endif
		err = -1;
		goto err_out;
	}
	/* Update the name of the region now we know the type of card */ 
	release_region(base, is_8bit(cosa)?2:4);
	if (!request_region(base, is_8bit(cosa)?2:4, cosa->type)) {
		printk(KERN_DEBUG "changing name at 0x%x failed.\n", base);
		return -1;
	}

	/* Now do IRQ autoprobe */
	if (irq < 0) {
		unsigned long irqs;
/*		pr_info("IRQ autoprobe\n"); */
		irqs = probe_irq_on();
		/* 
		 * Enable interrupt on tx buffer empty (it sure is) 
		 * really sure ?
		 * FIXME: When this code is not used as module, we should
		 * probably call udelay() instead of the interruptible sleep.
		 */
		set_current_state(TASK_INTERRUPTIBLE);
		cosa_putstatus(cosa, SR_TX_INT_ENA);
		schedule_timeout(msecs_to_jiffies(300));
		irq = probe_irq_off(irqs);
		/* Disable all IRQs from the card */
		cosa_putstatus(cosa, 0);
		/* Empty the received data register */
		cosa_getdata8(cosa);

		if (irq < 0) {
			pr_info("multiple interrupts obtained (%d, board at 0x%x)\n",
				irq, cosa->datareg);
			err = -1;
			goto err_out;
		}
		if (irq == 0) {
			pr_info("no interrupt obtained (board at 0x%x)\n",
				cosa->datareg);
		/*	return -1; */
		}
	}

	cosa->irq = irq;
	cosa->num = nr_cards;
	cosa->usage = 0;
	cosa->nchannels = 2;	/* FIXME: how to determine this? */

	if (request_irq(cosa->irq, cosa_interrupt, 0, cosa->type, cosa)) {
		err = -1;
		goto err_out;
	}
	if (request_dma(cosa->dma, cosa->type)) {
		err = -1;
		goto err_out1;
	}
	
	cosa->bouncebuf = kmalloc(COSA_MTU, GFP_KERNEL|GFP_DMA);
	if (!cosa->bouncebuf) {
		err = -ENOMEM;
		goto err_out2;
	}
	sprintf(cosa->name, "cosa%d", cosa->num);

	/* Initialize the per-channel data */
	cosa->chan = kcalloc(cosa->nchannels, sizeof(struct channel_data), GFP_KERNEL);
	if (!cosa->chan) {
		err = -ENOMEM;
		goto err_out3;
	}

	for (i = 0; i < cosa->nchannels; i++) {
		struct channel_data *chan = &cosa->chan[i];

		chan->cosa = cosa;
		chan->num = i;
		sprintf(chan->name, "cosa%dc%d", chan->cosa->num, i);

		/* Initialize the chardev data structures */
		mutex_init(&chan->rlock);
		sema_init(&chan->wsem, 1);

		/* Register the network interface */
		if (!(chan->netdev = alloc_hdlcdev(chan))) {
			pr_warn("%s: alloc_hdlcdev failed\n", chan->name);
			err = -ENOMEM;
			goto err_hdlcdev;
		}
		dev_to_hdlc(chan->netdev)->attach = cosa_net_attach;
		dev_to_hdlc(chan->netdev)->xmit = cosa_net_tx;
		chan->netdev->netdev_ops = &cosa_ops;
		chan->netdev->watchdog_timeo = TX_TIMEOUT;
		chan->netdev->base_addr = chan->cosa->datareg;
		chan->netdev->irq = chan->cosa->irq;
		chan->netdev->dma = chan->cosa->dma;
		err = register_hdlc_device(chan->netdev);
		if (err) {
			netdev_warn(chan->netdev,
				    "register_hdlc_device() failed\n");
			free_netdev(chan->netdev);
			goto err_hdlcdev;
		}
	}

	pr_info("cosa%d: %s (%s at 0x%x irq %d dma %d), %d channels\n",
		cosa->num, cosa->id_string, cosa->type,
		cosa->datareg, cosa->irq, cosa->dma, cosa->nchannels);

	return nr_cards++;

err_hdlcdev:
	while (i-- > 0) {
		unregister_hdlc_device(cosa->chan[i].netdev);
		free_netdev(cosa->chan[i].netdev);
	}
	kfree(cosa->chan);
err_out3:
	kfree(cosa->bouncebuf);
err_out2:
	free_dma(cosa->dma);
err_out1:
	free_irq(cosa->irq, cosa);
err_out:
	release_region(cosa->datareg,is_8bit(cosa)?2:4);
	pr_notice("cosa%d: allocating resources failed\n", cosa->num);
	return err;
}


/*---------- network device ---------- */

static int cosa_net_attach(struct net_device *dev, unsigned short encoding,
			   unsigned short parity)
{
	if (encoding == ENCODING_NRZ && parity == PARITY_CRC16_PR1_CCITT)
		return 0;
	return -EINVAL;
}

static int cosa_net_open(struct net_device *dev)
{
	struct channel_data *chan = dev_to_chan(dev);
	int err;
	unsigned long flags;

	if (!(chan->cosa->firmware_status & COSA_FW_START)) {
		pr_notice("%s: start the firmware first (status %d)\n",
			  chan->cosa->name, chan->cosa->firmware_status);
		return -EPERM;
	}
	spin_lock_irqsave(&chan->cosa->lock, flags);
	if (chan->usage != 0) {
		pr_warn("%s: cosa_net_open called with usage count %d\n",
			chan->name, chan->usage);
		spin_unlock_irqrestore(&chan->cosa->lock, flags);
		return -EBUSY;
	}
	chan->setup_rx = cosa_net_setup_rx;
	chan->tx_done = cosa_net_tx_done;
	chan->rx_done = cosa_net_rx_done;
	chan->usage = -1;
	chan->cosa->usage++;
	spin_unlock_irqrestore(&chan->cosa->lock, flags);

	err = hdlc_open(dev);
	if (err) {
		spin_lock_irqsave(&chan->cosa->lock, flags);
		chan->usage = 0;
		chan->cosa->usage--;
		spin_unlock_irqrestore(&chan->cosa->lock, flags);
		return err;
	}

	netif_start_queue(dev);
	cosa_enable_rx(chan);
	return 0;
}

static netdev_tx_t cosa_net_tx(struct sk_buff *skb,
				     struct net_device *dev)
{
	struct channel_data *chan = dev_to_chan(dev);

	netif_stop_queue(dev);

	chan->tx_skb = skb;
	cosa_start_tx(chan, skb->data, skb->len);
	return NETDEV_TX_OK;
}

static void cosa_net_timeout(struct net_device *dev)
{
	struct channel_data *chan = dev_to_chan(dev);

	if (test_bit(RXBIT, &chan->cosa->rxtx)) {
		chan->netdev->stats.rx_errors++;
		chan->netdev->stats.rx_missed_errors++;
	} else {
		chan->netdev->stats.tx_errors++;
		chan->netdev->stats.tx_aborted_errors++;
	}
	cosa_kick(chan->cosa);
	if (chan->tx_skb) {
		dev_kfree_skb(chan->tx_skb);
		chan->tx_skb = NULL;
	}
	netif_wake_queue(dev);
}

static int cosa_net_close(struct net_device *dev)
{
	struct channel_data *chan = dev_to_chan(dev);
	unsigned long flags;

	netif_stop_queue(dev);
	hdlc_close(dev);
	cosa_disable_rx(chan);
	spin_lock_irqsave(&chan->cosa->lock, flags);
	if (chan->rx_skb) {
		kfree_skb(chan->rx_skb);
		chan->rx_skb = NULL;
	}
	if (chan->tx_skb) {
		kfree_skb(chan->tx_skb);
		chan->tx_skb = NULL;
	}
	chan->usage = 0;
	chan->cosa->usage--;
	spin_unlock_irqrestore(&chan->cosa->lock, flags);
	return 0;
}

static char *cosa_net_setup_rx(struct channel_data *chan, int size)
{
	/*
	 * We can safely fall back to non-dma-able memory, because we have
	 * the cosa->bouncebuf pre-allocated.
	 */
	kfree_skb(chan->rx_skb);
	chan->rx_skb = dev_alloc_skb(size);
	if (chan->rx_skb == NULL) {
		pr_notice("%s: Memory squeeze, dropping packet\n", chan->name);
		chan->netdev->stats.rx_dropped++;
		return NULL;
	}
	netif_trans_update(chan->netdev);
	return skb_put(chan->rx_skb, size);
}

static int cosa_net_rx_done(struct channel_data *chan)
{
	if (!chan->rx_skb) {
		pr_warn("%s: rx_done with empty skb!\n", chan->name);
		chan->netdev->stats.rx_errors++;
		chan->netdev->stats.rx_frame_errors++;
		return 0;
	}
	chan->rx_skb->protocol = hdlc_type_trans(chan->rx_skb, chan->netdev);
	chan->rx_skb->dev = chan->netdev;
	skb_reset_mac_header(chan->rx_skb);
	chan->netdev->stats.rx_packets++;
	chan->netdev->stats.rx_bytes += chan->cosa->rxsize;
	netif_rx(chan->rx_skb);
	chan->rx_skb = NULL;
	return 0;
}

/* ARGSUSED */
static int cosa_net_tx_done(struct channel_data *chan, int size)
{
	if (!chan->tx_skb) {
		pr_warn("%s: tx_done with empty skb!\n", chan->name);
		chan->netdev->stats.tx_errors++;
		chan->netdev->stats.tx_aborted_errors++;
		return 1;
	}
	dev_kfree_skb_irq(chan->tx_skb);
	chan->tx_skb = NULL;
	chan->netdev->stats.tx_packets++;
	chan->netdev->stats.tx_bytes += size;
	netif_wake_queue(chan->netdev);
	return 1;
}

/*---------- Character device ---------- */

static ssize_t cosa_read(struct file *file,
	char __user *buf, size_t count, loff_t *ppos)
{
	DECLARE_WAITQUEUE(wait, current);
	unsigned long flags;
	struct channel_data *chan = file->private_data;
	struct cosa_data *cosa = chan->cosa;
	char *kbuf;

	if (!(cosa->firmware_status & COSA_FW_START)) {
		pr_notice("%s: start the firmware first (status %d)\n",
			  cosa->name, cosa->firmware_status);
		return -EPERM;
	}
	if (mutex_lock_interruptible(&chan->rlock))
		return -ERESTARTSYS;
	
	chan->rxdata = kmalloc(COSA_MTU, GFP_DMA|GFP_KERNEL);
	if (chan->rxdata == NULL) {
		mutex_unlock(&chan->rlock);
		return -ENOMEM;
	}

	chan->rx_status = 0;
	cosa_enable_rx(chan);
	spin_lock_irqsave(&cosa->lock, flags);
	add_wait_queue(&chan->rxwaitq, &wait);
	while (!chan->rx_status) {
		set_current_state(TASK_INTERRUPTIBLE);
		spin_unlock_irqrestore(&cosa->lock, flags);
		schedule();
		spin_lock_irqsave(&cosa->lock, flags);
		if (signal_pending(current) && chan->rx_status == 0) {
			chan->rx_status = 1;
			remove_wait_queue(&chan->rxwaitq, &wait);
			__set_current_state(TASK_RUNNING);
			spin_unlock_irqrestore(&cosa->lock, flags);
			mutex_unlock(&chan->rlock);
			return -ERESTARTSYS;
		}
	}
	remove_wait_queue(&chan->rxwaitq, &wait);
	__set_current_state(TASK_RUNNING);
	kbuf = chan->rxdata;
	count = chan->rxsize;
	spin_unlock_irqrestore(&cosa->lock, flags);
	mutex_unlock(&chan->rlock);

	if (copy_to_user(buf, kbuf, count)) {
		kfree(kbuf);
		return -EFAULT;
	}
	kfree(kbuf);
	return count;
}

static char *chrdev_setup_rx(struct channel_data *chan, int size)
{
	/* Expect size <= COSA_MTU */
	chan->rxsize = size;
	return chan->rxdata;
}

static int chrdev_rx_done(struct channel_data *chan)
{
	if (chan->rx_status) { /* Reader has died */
		kfree(chan->rxdata);
		up(&chan->wsem);
	}
	chan->rx_status = 1;
	wake_up_interruptible(&chan->rxwaitq);
	return 1;
}


static ssize_t cosa_write(struct file *file,
	const char __user *buf, size_t count, loff_t *ppos)
{
	DECLARE_WAITQUEUE(wait, current);
	struct channel_data *chan = file->private_data;
	struct cosa_data *cosa = chan->cosa;
	unsigned long flags;
	char *kbuf;

	if (!(cosa->firmware_status & COSA_FW_START)) {
		pr_notice("%s: start the firmware first (status %d)\n",
			  cosa->name, cosa->firmware_status);
		return -EPERM;
	}
	if (down_interruptible(&chan->wsem))
		return -ERESTARTSYS;

	if (count > COSA_MTU)
		count = COSA_MTU;
	
	/* Allocate the buffer */
	kbuf = kmalloc(count, GFP_KERNEL|GFP_DMA);
	if (kbuf == NULL) {
		up(&chan->wsem);
		return -ENOMEM;
	}
	if (copy_from_user(kbuf, buf, count)) {
		up(&chan->wsem);
		kfree(kbuf);
		return -EFAULT;
	}
	chan->tx_status=0;
	cosa_start_tx(chan, kbuf, count);

	spin_lock_irqsave(&cosa->lock, flags);
	add_wait_queue(&chan->txwaitq, &wait);
	while (!chan->tx_status) {
		set_current_state(TASK_INTERRUPTIBLE);
		spin_unlock_irqrestore(&cosa->lock, flags);
		schedule();
		spin_lock_irqsave(&cosa->lock, flags);
		if (signal_pending(current) && chan->tx_status == 0) {
			chan->tx_status = 1;
			remove_wait_queue(&chan->txwaitq, &wait);
			__set_current_state(TASK_RUNNING);
			chan->tx_status = 1;
			spin_unlock_irqrestore(&cosa->lock, flags);
			up(&chan->wsem);
			return -ERESTARTSYS;
		}
	}
	remove_wait_queue(&chan->txwaitq, &wait);
	__set_current_state(TASK_RUNNING);
	up(&chan->wsem);
	spin_unlock_irqrestore(&cosa->lock, flags);
	kfree(kbuf);
	return count;
}

static int chrdev_tx_done(struct channel_data *chan, int size)
{
	if (chan->tx_status) { /* Writer was interrupted */
		kfree(chan->txbuf);
		up(&chan->wsem);
	}
	chan->tx_status = 1;
	wake_up_interruptible(&chan->txwaitq);
	return 1;
}

static unsigned int cosa_poll(struct file *file, poll_table *poll)
{
	pr_info("cosa_poll is here\n");
	return 0;
}

static int cosa_open(struct inode *inode, struct file *file)
{
	struct cosa_data *cosa;
	struct channel_data *chan;
	unsigned long flags;
	int n;
	int ret = 0;

	mutex_lock(&cosa_chardev_mutex);
	if ((n=iminor(file_inode(file))>>CARD_MINOR_BITS)
		>= nr_cards) {
		ret = -ENODEV;
		goto out;
	}
	cosa = cosa_cards+n;

	if ((n=iminor(file_inode(file))
		& ((1<<CARD_MINOR_BITS)-1)) >= cosa->nchannels) {
		ret = -ENODEV;
		goto out;
	}
	chan = cosa->chan + n;
	
	file->private_data = chan;

	spin_lock_irqsave(&cosa->lock, flags);

	if (chan->usage < 0) { /* in netdev mode */
		spin_unlock_irqrestore(&cosa->lock, flags);
		ret = -EBUSY;
		goto out;
	}
	cosa->usage++;
	chan->usage++;

	chan->tx_done = chrdev_tx_done;
	chan->setup_rx = chrdev_setup_rx;
	chan->rx_done = chrdev_rx_done;
	spin_unlock_irqrestore(&cosa->lock, flags);
out:
	mutex_unlock(&cosa_chardev_mutex);
	return ret;
}

static int cosa_release(struct inode *inode, struct file *file)
{
	struct channel_data *channel = file->private_data;
	struct cosa_data *cosa;
	unsigned long flags;

	cosa = channel->cosa;
	spin_lock_irqsave(&cosa->lock, flags);
	cosa->usage--;
	channel->usage--;
	spin_unlock_irqrestore(&cosa->lock, flags);
	return 0;
}

#ifdef COSA_FASYNC_WORKING
static struct fasync_struct *fasync[256] = { NULL, };

/* To be done ... */
static int cosa_fasync(struct inode *inode, struct file *file, int on)
{
        int port = iminor(inode);

	return fasync_helper(inode, file, on, &fasync[port]);
}
#endif


/* ---------- Ioctls ---------- */

/*
 * Ioctl subroutines can safely be made inline, because they are called
 * only from cosa_ioctl().
 */
static inline int cosa_reset(struct cosa_data *cosa)
{
	char idstring[COSA_MAX_ID_STRING];
	if (cosa->usage > 1)
		pr_info("cosa%d: WARNING: reset requested with cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->num, cosa->usage);
	cosa->firmware_status &= ~(COSA_FW_RESET|COSA_FW_START);
	if (cosa_reset_and_read_id(cosa, idstring) < 0) {
		pr_notice("cosa%d: reset failed\n", cosa->num);
		return -EIO;
	}
	pr_info("cosa%d: resetting device: %s\n", cosa->num, idstring);
	cosa->firmware_status |= COSA_FW_RESET;
	return 0;
}

/* High-level function to download data into COSA memory. Calls download() */
static inline int cosa_download(struct cosa_data *cosa, void __user *arg)
{
	struct cosa_download d;
	int i;

	if (cosa->usage > 1)
		pr_info("%s: WARNING: download of microcode requested with cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->name, cosa->usage);
	if (!(cosa->firmware_status & COSA_FW_RESET)) {
		pr_notice("%s: reset the card first (status %d)\n",
			  cosa->name, cosa->firmware_status);
		return -EPERM;
	}
	
	if (copy_from_user(&d, arg, sizeof(d)))
		return -EFAULT;

	if (d.addr < 0 || d.addr > COSA_MAX_FIRMWARE_SIZE)
		return -EINVAL;
	if (d.len < 0 || d.len > COSA_MAX_FIRMWARE_SIZE)
		return -EINVAL;


	/* If something fails, force the user to reset the card */
	cosa->firmware_status &= ~(COSA_FW_RESET|COSA_FW_DOWNLOAD);

	i = download(cosa, d.code, d.len, d.addr);
	if (i < 0) {
		pr_notice("cosa%d: microcode download failed: %d\n",
			  cosa->num, i);
		return -EIO;
	}
	pr_info("cosa%d: downloading microcode - 0x%04x bytes at 0x%04x\n",
		cosa->num, d.len, d.addr);
	cosa->firmware_status |= COSA_FW_RESET|COSA_FW_DOWNLOAD;
	return 0;
}

/* High-level function to read COSA memory. Calls readmem() */
static inline int cosa_readmem(struct cosa_data *cosa, void __user *arg)
{
	struct cosa_download d;
	int i;

	if (cosa->usage > 1)
		pr_info("cosa%d: WARNING: readmem requested with cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->num, cosa->usage);
	if (!(cosa->firmware_status & COSA_FW_RESET)) {
		pr_notice("%s: reset the card first (status %d)\n",
			  cosa->name, cosa->firmware_status);
		return -EPERM;
	}

	if (copy_from_user(&d, arg, sizeof(d)))
		return -EFAULT;

	/* If something fails, force the user to reset the card */
	cosa->firmware_status &= ~COSA_FW_RESET;

	i = readmem(cosa, d.code, d.len, d.addr);
	if (i < 0) {
		pr_notice("cosa%d: reading memory failed: %d\n", cosa->num, i);
		return -EIO;
	}
	pr_info("cosa%d: reading card memory - 0x%04x bytes at 0x%04x\n",
		cosa->num, d.len, d.addr);
	cosa->firmware_status |= COSA_FW_RESET;
	return 0;
}

/* High-level function to start microcode. Calls startmicrocode(). */
static inline int cosa_start(struct cosa_data *cosa, int address)
{
	int i;

	if (cosa->usage > 1)
		pr_info("cosa%d: WARNING: start microcode requested with cosa->usage > 1 (%d). Odd things may happen.\n",
			cosa->num, cosa->usage);

	if ((cosa->firmware_status & (COSA_FW_RESET|COSA_FW_DOWNLOAD))
		!= (COSA_FW_RESET|COSA_FW_DOWNLOAD)) {
		pr_notice("%s: download the microcode and/or reset the card first (status %d)\n",
			  cosa->name, cosa->firmware_status);
		return -EPERM;
	}
	cosa->firmware_status &= ~COSA_FW_RESET;
	if ((i=startmicrocode(cosa, address)) < 0) {
		pr_notice("cosa%d: start microcode at 0x%04x failed: %d\n",
			  cosa->num, address, i);
		return -EIO;
	}
	pr_info("cosa%d: starting microcode at 0x%04x\n", cosa->num, address);
	cosa->startaddr = address;
	cosa->firmware_status |= COSA_FW_START;
	return 0;
}
		
/* Buffer of size at least COSA_MAX_ID_STRING is expected */
static inline int cosa_getidstr(struct cosa_data *cosa, char __user *string)
{
	int l = strlen(cosa->id_string)+1;
	if (copy_to_user(string, cosa->id_string, l))
		return -EFAULT;
	return l;
}

/* Buffer of size at least COSA_MAX_ID_STRING is expected */
static inline int cosa_gettype(struct cosa_data *cosa, char __user *string)
{
	int l = strlen(cosa->type)+1;
	if (copy_to_user(string, cosa->type, l))
		return -EFAULT;
	return l;
}

static int cosa_ioctl_common(struct cosa_data *cosa,
	struct channel_data *channel, unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	switch (cmd) {
	case COSAIORSET:	/* Reset the device */
		if (!capable(CAP_NET_ADMIN))
			return -EACCES;
		return cosa_reset(cosa);
	case COSAIOSTRT:	/* Start the firmware */
		if (!capable(CAP_SYS_RAWIO))
			return -EACCES;
		return cosa_start(cosa, arg);
	case COSAIODOWNLD:	/* Download the firmware */
		if (!capable(CAP_SYS_RAWIO))
			return -EACCES;
		
		return cosa_download(cosa, argp);
	case COSAIORMEM:
		if (!capable(CAP_SYS_RAWIO))
			return -EACCES;
		return cosa_readmem(cosa, argp);
	case COSAIORTYPE:
		return cosa_gettype(cosa, argp);
	case COSAIORIDSTR:
		return cosa_getidstr(cosa, argp);
	case COSAIONRCARDS:
		return nr_cards;
	case COSAIONRCHANS:
		return cosa->nchannels;
	case COSAIOBMSET:
		if (!capable(CAP_SYS_RAWIO))
			return -EACCES;
		if (is_8bit(cosa))
			return -EINVAL;
		if (arg != COSA_BM_OFF && arg != COSA_BM_ON)
			return -EINVAL;
		cosa->busmaster = arg;
		return 0;
	case COSAIOBMGET:
		return cosa->busmaster;
	}
	return -ENOIOCTLCMD;
}

static int cosa_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	int rv;
	struct channel_data *chan = dev_to_chan(dev);
	rv = cosa_ioctl_common(chan->cosa, chan, cmd,
			       (unsigned long)ifr->ifr_data);
	if (rv != -ENOIOCTLCMD)
		return rv;
	return hdlc_ioctl(dev, ifr, cmd);
}

static long cosa_chardev_ioctl(struct file *file, unsigned int cmd,
							unsigned long arg)
{
	struct channel_data *channel = file->private_data;
	struct cosa_data *cosa;
	long ret;

	mutex_lock(&cosa_chardev_mutex);
	cosa = channel->cosa;
	ret = cosa_ioctl_common(cosa, channel, cmd, arg);
	mutex_unlock(&cosa_chardev_mutex);
	return ret;
}


/*---------- HW layer interface ---------- */

/*
 * The higher layer can bind itself to the HW layer by setting the callbacks
 * in the channel_data structure and by using these routines.
 */
static void cosa_enable_rx(struct channel_data *chan)
{
	struct cosa_data *cosa = chan->cosa;

	if (!test_and_set_bit(chan->num, &cosa->rxbitmap))
		put_driver_status(cosa);
}

static void cosa_disable_rx(struct channel_data *chan)
{
	struct cosa_data *cosa = chan->cosa;

	if (test_and_clear_bit(chan->num, &cosa->rxbitmap))
		put_driver_status(cosa);
}

/*
 * FIXME: This routine probably should check for cosa_start_tx() called when
 * the previous transmit is still unfinished. In this case the non-zero
 * return value should indicate to the caller that the queuing(sp?) up
 * the transmit has failed.
 */
static int cosa_start_tx(struct channel_data *chan, char *buf, int len)
{
	struct cosa_data *cosa = chan->cosa;
	unsigned long flags;
#ifdef DEBUG_DATA
	int i;

	pr_info("cosa%dc%d: starting tx(0x%x)",
		chan->cosa->num, chan->num, len);
	for (i=0; i<len; i++)
		pr_cont(" %02x", buf[i]&0xff);
	pr_cont("\n");
#endif
	spin_lock_irqsave(&cosa->lock, flags);
	chan->txbuf = buf;
	chan->txsize = len;
	if (len > COSA_MTU)
		chan->txsize = COSA_MTU;
	spin_unlock_irqrestore(&cosa->lock, flags);

	/* Tell the firmware we are ready */
	set_bit(chan->num, &cosa->txbitmap);
	put_driver_status(cosa);

	return 0;
}

static void put_driver_status(struct cosa_data *cosa)
{
	unsigned long flags;
	int status;

	spin_lock_irqsave(&cosa->lock, flags);

	status = (cosa->rxbitmap ? DRIVER_RX_READY : 0)
		| (cosa->txbitmap ? DRIVER_TX_READY : 0)
		| (cosa->txbitmap? ~(cosa->txbitmap<<DRIVER_TXMAP_SHIFT)
			&DRIVER_TXMAP_MASK : 0);
	if (!cosa->rxtx) {
		if (cosa->rxbitmap|cosa->txbitmap) {
			if (!cosa->enabled) {
				cosa_putstatus(cosa, SR_RX_INT_ENA);
#ifdef DEBUG_IO
				debug_status_out(cosa, SR_RX_INT_ENA);
#endif
				cosa->enabled = 1;
			}
		} else if (cosa->enabled) {
			cosa->enabled = 0;
			cosa_putstatus(cosa, 0);
#ifdef DEBUG_IO
			debug_status_out(cosa, 0);
#endif
		}
		cosa_putdata8(cosa, status);
#ifdef DEBUG_IO
		debug_data_cmd(cosa, status);
#endif
	}
	spin_unlock_irqrestore(&cosa->lock, flags);
}

static void put_driver_status_nolock(struct cosa_data *cosa)
{
	int status;

	status = (cosa->rxbitmap ? DRIVER_RX_READY : 0)
		| (cosa->txbitmap ? DRIVER_TX_READY : 0)
		| (cosa->txbitmap? ~(cosa->txbitmap<<DRIVER_TXMAP_SHIFT)
			&DRIVER_TXMAP_MASK : 0);

	if (cosa->rxbitmap|cosa->txbitmap) {
		cosa_putstatus(cosa, SR_RX_INT_ENA);
#ifdef DEBUG_IO
		debug_status_out(cosa, SR_RX_INT_ENA);
#endif
		cosa->enabled = 1;
	} else {
		cosa_putstatus(cosa, 0);
#ifdef DEBUG_IO
		debug_status_out(cosa, 0);
#endif
		cosa->enabled = 0;
	}
	cosa_putdata8(cosa, status);
#ifdef DEBUG_IO
	debug_data_cmd(cosa, status);
#endif
}

/*
 * The "kickme" function: When the DMA times out, this is called to
 * clean up the driver status.
 * FIXME: Preliminary support, the interface is probably wrong.
 */
static void cosa_kick(struct cosa_data *cosa)
{
	unsigned long flags, flags1;
	char *s = "(probably) IRQ";

	if (test_bit(RXBIT, &cosa->rxtx))
		s = "RX DMA";
	if (test_bit(TXBIT, &cosa->rxtx))
		s = "TX DMA";

	pr_info("%s: %s timeout - restarting\n", cosa->name, s);
	spin_lock_irqsave(&cosa->lock, flags);
	cosa->rxtx = 0;

	flags1 = claim_dma_lock();
	disable_dma(cosa->dma);
	clear_dma_ff(cosa->dma);
	release_dma_lock(flags1);

	/* FIXME: Anything else? */
	udelay(100);
	cosa_putstatus(cosa, 0);
	udelay(100);
	(void) cosa_getdata8(cosa);
	udelay(100);
	cosa_putdata8(cosa, 0);
	udelay(100);
	put_driver_status_nolock(cosa);
	spin_unlock_irqrestore(&cosa->lock, flags);
}

/*
 * Check if the whole buffer is DMA-able. It means it is below the 16M of
 * physical memory and doesn't span the 64k boundary. For now it seems
 * SKB's never do this, but we'll check this anyway.
 */
static int cosa_dma_able(struct channel_data *chan, char *buf, int len)
{
	static int count;
	unsigned long b = (unsigned long)buf;
	if (b+len >= MAX_DMA_ADDRESS)
		return 0;
	if ((b^ (b+len)) & 0x10000) {
		if (count++ < 5)
			pr_info("%s: packet spanning a 64k boundary\n",
				chan->name);
		return 0;
	}
	return 1;
}


/* ---------- The SRP/COSA ROM monitor functions ---------- */

/*
 * Downloading SRP microcode: say "w" to SRP monitor, it answers by "w=",
 * drivers need to say 4-digit hex number meaning start address of the microcode
 * separated by a single space. Monitor replies by saying " =". Now driver
 * has to write 4-digit hex number meaning the last byte address ended
 * by a single space. Monitor has to reply with a space. Now the download
 * begins. After the download monitor replies with "\r\n." (CR LF dot).
 */
static int download(struct cosa_data *cosa, const char __user *microcode, int length, int address)
{
	int i;

	if (put_wait_data(cosa, 'w') == -1) return -1;
	if ((i=get_wait_data(cosa)) != 'w') { printk("dnld: 0x%04x\n",i); return -2;}
	if (get_wait_data(cosa) != '=') return -3;

	if (puthexnumber(cosa, address) < 0) return -4;
	if (put_wait_data(cosa, ' ') == -1) return -10;
	if (get_wait_data(cosa) != ' ') return -11;
	if (get_wait_data(cosa) != '=') return -12;

	if (puthexnumber(cosa, address+length-1) < 0) return -13;
	if (put_wait_data(cosa, ' ') == -1) return -18;
	if (get_wait_data(cosa) != ' ') return -19;

	while (length--) {
		char c;
#ifndef SRP_DOWNLOAD_AT_BOOT
		if (get_user(c, microcode))
			return -23; /* ??? */
#else
		c = *microcode;
#endif
		if (put_wait_data(cosa, c) == -1)
			return -20;
		microcode++;
	}

	if (get_wait_data(cosa) != '\r') return -21;
	if (get_wait_data(cosa) != '\n') return -22;
	if (get_wait_data(cosa) != '.') return -23;
#if 0
	printk(KERN_DEBUG "cosa%d: download completed.\n", cosa->num);
#endif
	return 0;
}


/*
 * Starting microcode is done via the "g" command of the SRP monitor.
 * The chat should be the following: "g" "g=" "<addr><CR>"
 * "<CR><CR><LF><CR><LF>".
 */
static int startmicrocode(struct cosa_data *cosa, int address)
{
	if (put_wait_data(cosa, 'g') == -1) return -1;
	if (get_wait_data(cosa) != 'g') return -2;
	if (get_wait_data(cosa) != '=') return -3;

	if (puthexnumber(cosa, address) < 0) return -4;
	if (put_wait_data(cosa, '\r') == -1) return -5;
	
	if (get_wait_data(cosa) != '\r') return -6;
	if (get_wait_data(cosa) != '\r') return -7;
	if (get_wait_data(cosa) != '\n') return -8;
	if (get_wait_data(cosa) != '\r') return -9;
	if (get_wait_data(cosa) != '\n') return -10;
#if 0
	printk(KERN_DEBUG "cosa%d: microcode started\n", cosa->num);
#endif
	return 0;
}

/*
 * Reading memory is done via the "r" command of the SRP monitor.
 * The chat is the following "r" "r=" "<addr> " " =" "<last_byte> " " "
 * Then driver can read the data and the conversation is finished
 * by SRP monitor sending "<CR><LF>." (dot at the end).
 *
 * This routine is not needed during the normal operation and serves
 * for debugging purposes only.
 */
static int readmem(struct cosa_data *cosa, char __user *microcode, int length, int address)
{
	if (put_wait_data(cosa, 'r') == -1) return -1;
	if ((get_wait_data(cosa)) != 'r') return -2;
	if ((get_wait_data(cosa)) != '=') return -3;

	if (puthexnumber(cosa, address) < 0) return -4;
	if (put_wait_data(cosa, ' ') == -1) return -5;
	if (get_wait_data(cosa) != ' ') return -6;
	if (get_wait_data(cosa) != '=') return -7;

	if (puthexnumber(cosa, address+length-1) < 0) return -8;
	if (put_wait_data(cosa, ' ') == -1) return -9;
	if (get_wait_data(cosa) != ' ') return -10;

	while (length--) {
		char c;
		int i;
		if ((i=get_wait_data(cosa)) == -1) {
			pr_info("0x%04x bytes remaining\n", length);
			return -11;
		}
		c=i;
#if 1
		if (put_user(c, microcode))
			return -23; /* ??? */
#else
		*microcode = c;
#endif
		microcode++;
	}

	if (get_wait_data(cosa) != '\r') return -21;
	if (get_wait_data(cosa) != '\n') return -22;
	if (get_wait_data(cosa) != '.') return -23;
#if 0
	printk(KERN_DEBUG "cosa%d: readmem completed.\n", cosa->num);
#endif
	return 0;
}

/*
 * This function resets the device and reads the initial prompt
 * of the device's ROM monitor.
 */
static int cosa_reset_and_read_id(struct cosa_data *cosa, char *idstring)
{
	int i=0, id=0, prev=0, curr=0;

	/* Reset the card ... */
	cosa_putstatus(cosa, 0);
	cosa_getdata8(cosa);
	cosa_putstatus(cosa, SR_RST);
	msleep(500);
	/* Disable all IRQs from the card */
	cosa_putstatus(cosa, 0);

	/*
	 * Try to read the ID string. The card then prints out the
	 * identification string ended by the "\n\x2e".
	 *
	 * The following loop is indexed through i (instead of id)
	 * to avoid looping forever when for any reason
	 * the port returns '\r', '\n' or '\x2e' permanently.
	 */
	for (i=0; i<COSA_MAX_ID_STRING-1; i++, prev=curr) {
		if ((curr = get_wait_data(cosa)) == -1) {
			return -1;
		}
		curr &= 0xff;
		if (curr != '\r' && curr != '\n' && curr != 0x2e)
			idstring[id++] = curr;
		if (curr == 0x2e && prev == '\n')
			break;
	}
	/* Perhaps we should fail when i==COSA_MAX_ID_STRING-1 ? */
	idstring[id] = '\0';
	return id;
}


/* ---------- Auxiliary routines for COSA/SRP monitor ---------- */

/*
 * This routine gets the data byte from the card waiting for the SR_RX_RDY
 * bit to be set in a loop. It should be used in the exceptional cases
 * only (for example when resetting the card or downloading the firmware.
 */
static int get_wait_data(struct cosa_data *cosa)
{
	int retries = 1000;

	while (--retries) {
		/* read data and return them */
		if (cosa_getstatus(cosa) & SR_RX_RDY) {
			short r;
			r = cosa_getdata8(cosa);
#if 0
			pr_info("get_wait_data returning after %d retries\n",
				999-retries);
#endif
			return r;
		}
		/* sleep if not ready to read */
		schedule_timeout_interruptible(1);
	}
	pr_info("timeout in get_wait_data (status 0x%x)\n",
		cosa_getstatus(cosa));
	return -1;
}

/*
 * This routine puts the data byte to the card waiting for the SR_TX_RDY
 * bit to be set in a loop. It should be used in the exceptional cases
 * only (for example when resetting the card or downloading the firmware).
 */
static int put_wait_data(struct cosa_data *cosa, int data)
{
	int retries = 1000;
	while (--retries) {
		/* read data and return them */
		if (cosa_getstatus(cosa) & SR_TX_RDY) {
			cosa_putdata8(cosa, data);
#if 0
			pr_info("Putdata: %d retries\n", 999-retries);
#endif
			return 0;
		}
#if 0
		/* sleep if not ready to read */
		schedule_timeout_interruptible(1);
#endif
	}
	pr_info("cosa%d: timeout in put_wait_data (status 0x%x)\n",
		cosa->num, cosa_getstatus(cosa));
	return -1;
}
	
/* 
 * The following routine puts the hexadecimal number into the SRP monitor
 * and verifies the proper echo of the sent bytes. Returns 0 on success,
 * negative number on failure (-1,-3,-5,-7) means that put_wait_data() failed,
 * (-2,-4,-6,-8) means that reading echo failed.
 */
static int puthexnumber(struct cosa_data *cosa, int number)
{
	char temp[5];
	int i;

	/* Well, I should probably replace this by something faster. */
	sprintf(temp, "%04X", number);
	for (i=0; i<4; i++) {
		if (put_wait_data(cosa, temp[i]) == -1) {
			pr_notice("cosa%d: puthexnumber failed to write byte %d\n",
				  cosa->num, i);
			return -1-2*i;
		}
		if (get_wait_data(cosa) != temp[i]) {
			pr_notice("cosa%d: puthexhumber failed to read echo of byte %d\n",
				  cosa->num, i);
			return -2-2*i;
		}
	}
	return 0;
}


/* ---------- Interrupt routines ---------- */

/*
 * There are three types of interrupt:
 * At the beginning of transmit - this handled is in tx_interrupt(),
 * at the beginning of receive - it is in rx_interrupt() and
 * at the end of transmit/receive - it is the eot_interrupt() function.
 * These functions are multiplexed by cosa_interrupt() according to the
 * COSA status byte. I have moved the rx/tx/eot interrupt handling into
 * separate functions to make it more readable. These functions are inline,
 * so there should be no overhead of function call.
 * 
 * In the COSA bus-master mode, we need to tell the card the address of a
 * buffer. Unfortunately, COSA may be too slow for us, so we must busy-wait.
 * It's time to use the bottom half :-(
 */

/*
 * Transmit interrupt routine - called when COSA is willing to obtain
 * data from the OS. The most tricky part of the routine is selection
 * of channel we (OS) want to send packet for. For SRP we should probably
 * use the round-robin approach. The newer COSA firmwares have a simple
 * flow-control - in the status word has bits 2 and 3 set to 1 means that the
 * channel 0 or 1 doesn't want to receive data.
 *
 * It seems there is a bug in COSA firmware (need to trace it further):
 * When the driver status says that the kernel has no more data for transmit
 * (e.g. at the end of TX DMA) and then the kernel changes its mind
 * (e.g. new packet is queued to hard_start_xmit()), the card issues
 * the TX interrupt but does not mark the channel as ready-to-transmit.
 * The fix seems to be to push the packet to COSA despite its request.
 * We first try to obey the card's opinion, and then fall back to forced TX.
 */
static inline void tx_interrupt(struct cosa_data *cosa, int status)
{
	unsigned long flags, flags1;
#ifdef DEBUG_IRQS
	pr_info("cosa%d: SR_DOWN_REQUEST status=0x%04x\n", cosa->num, status);
#endif
	spin_lock_irqsave(&cosa->lock, flags);
	set_bit(TXBIT, &cosa->rxtx);
	if (!test_bit(IRQBIT, &cosa->rxtx)) {
		/* flow control, see the comment above */
		int i=0;
		if (!cosa->txbitmap) {
			pr_warn("%s: No channel wants data in TX IRQ. Expect DMA timeout.\n",
				cosa->name);
			put_driver_status_nolock(cosa);
			clear_bit(TXBIT, &cosa->rxtx);
			spin_unlock_irqrestore(&cosa->lock, flags);
			return;
		}
		while (1) {
			cosa->txchan++;
			i++;
			if (cosa->txchan >= cosa->nchannels)
				cosa->txchan = 0;
			if (!(cosa->txbitmap & (1<<cosa->txchan)))
				continue;
			if (~status & (1 << (cosa->txchan+DRIVER_TXMAP_SHIFT)))
				break;
			/* in second pass, accept first ready-to-TX channel */
			if (i > cosa->nchannels) {
				/* Can be safely ignored */
#ifdef DEBUG_IRQS
				printk(KERN_DEBUG "%s: Forcing TX "
					"to not-ready channel %d\n",
					cosa->name, cosa->txchan);
#endif
				break;
			}
		}

		cosa->txsize = cosa->chan[cosa->txchan].txsize;
		if (cosa_dma_able(cosa->chan+cosa->txchan,
			cosa->chan[cosa->txchan].txbuf, cosa->txsize)) {
			cosa->txbuf = cosa->chan[cosa->txchan].txbuf;
		} else {
			memcpy(cosa->bouncebuf, cosa->chan[cosa->txchan].txbuf,
				cosa->txsize);
			cosa->txbuf = cosa->bouncebuf;
		}
	}

	if (is_8bit(cosa)) {
		if (!test_bit(IRQBIT, &cosa->rxtx)) {
			cosa_putstatus(cosa, SR_TX_INT_ENA);
			cosa_putdata8(cosa, ((cosa->txchan << 5) & 0xe0)|
				((cosa->txsize >> 8) & 0x1f));
#ifdef DEBUG_IO
			debug_status_out(cosa, SR_TX_INT_ENA);
			debug_data_out(cosa, ((cosa->txchan << 5) & 0xe0)|
                                ((cosa->txsize >> 8) & 0x1f));
			debug_data_in(cosa, cosa_getdata8(cosa));
#else
			cosa_getdata8(cosa);
#endif
			set_bit(IRQBIT, &cosa->rxtx);
			spin_unlock_irqrestore(&cosa->lock, flags);
			return;
		} else {
			clear_bit(IRQBIT, &cosa->rxtx);
			cosa_putstatus(cosa, 0);
			cosa_putdata8(cosa, cosa->txsize&0xff);
#ifdef DEBUG_IO
			debug_status_out(cosa, 0);
			debug_data_out(cosa, cosa->txsize&0xff);
#endif
		}
	} else {
		cosa_putstatus(cosa, SR_TX_INT_ENA);
		cosa_putdata16(cosa, ((cosa->txchan<<13) & 0xe000)
			| (cosa->txsize & 0x1fff));
#ifdef DEBUG_IO
		debug_status_out(cosa, SR_TX_INT_ENA);
		debug_data_out(cosa, ((cosa->txchan<<13) & 0xe000)
                        | (cosa->txsize & 0x1fff));
		debug_data_in(cosa, cosa_getdata8(cosa));
		debug_status_out(cosa, 0);
#else
		cosa_getdata8(cosa);
#endif
		cosa_putstatus(cosa, 0);
	}

	if (cosa->busmaster) {
		unsigned long addr = virt_to_bus(cosa->txbuf);
		int count=0;
		pr_info("busmaster IRQ\n");
		while (!(cosa_getstatus(cosa)&SR_TX_RDY)) {
			count++;
			udelay(10);
			if (count > 1000) break;
		}
		pr_info("status %x\n", cosa_getstatus(cosa));
		pr_info("ready after %d loops\n", count);
		cosa_putdata16(cosa, (addr >> 16)&0xffff);

		count = 0;
		while (!(cosa_getstatus(cosa)&SR_TX_RDY)) {
			count++;
			if (count > 1000) break;
			udelay(10);
		}
		pr_info("ready after %d loops\n", count);
		cosa_putdata16(cosa, addr &0xffff);
		flags1 = claim_dma_lock();
		set_dma_mode(cosa->dma, DMA_MODE_CASCADE);
		enable_dma(cosa->dma);
		release_dma_lock(flags1);
	} else {
		/* start the DMA */
		flags1 = claim_dma_lock();
		disable_dma(cosa->dma);
		clear_dma_ff(cosa->dma);
		set_dma_mode(cosa->dma, DMA_MODE_WRITE);
		set_dma_addr(cosa->dma, virt_to_bus(cosa->txbuf));
		set_dma_count(cosa->dma, cosa->txsize);
		enable_dma(cosa->dma);
		release_dma_lock(flags1);
	}
	cosa_putstatus(cosa, SR_TX_DMA_ENA|SR_USR_INT_ENA);
#ifdef DEBUG_IO
	debug_status_out(cosa, SR_TX_DMA_ENA|SR_USR_INT_ENA);
#endif
	spin_unlock_irqrestore(&cosa->lock, flags);
}

static inline void rx_interrupt(struct cosa_data *cosa, int status)
{
	unsigned long flags;
#ifdef DEBUG_IRQS
	pr_info("cosa%d: SR_UP_REQUEST\n", cosa->num);
#endif

	spin_lock_irqsave(&cosa->lock, flags);
	set_bit(RXBIT, &cosa->rxtx);

	if (is_8bit(cosa)) {
		if (!test_bit(IRQBIT, &cosa->rxtx)) {
			set_bit(IRQBIT, &cosa->rxtx);
			put_driver_status_nolock(cosa);
			cosa->rxsize = cosa_getdata8(cosa) <<8;
#ifdef DEBUG_IO
			debug_data_in(cosa, cosa->rxsize >> 8);
#endif
			spin_unlock_irqrestore(&cosa->lock, flags);
			return;
		} else {
			clear_bit(IRQBIT, &cosa->rxtx);
			cosa->rxsize |= cosa_getdata8(cosa) & 0xff;
#ifdef DEBUG_IO
			debug_data_in(cosa, cosa->rxsize & 0xff);
#endif
#if 0
			pr_info("cosa%d: receive rxsize = (0x%04x)\n",
				cosa->num, cosa->rxsize);
#endif
		}
	} else {
		cosa->rxsize = cosa_getdata16(cosa);
#ifdef DEBUG_IO
		debug_data_in(cosa, cosa->rxsize);
#endif
#if 0
		pr_info("cosa%d: receive rxsize = (0x%04x)\n",
			cosa->num, cosa->rxsize);
#endif
	}
	if (((cosa->rxsize & 0xe000) >> 13) >= cosa->nchannels) {
		pr_warn("%s: rx for unknown channel (0x%04x)\n",
			cosa->name, cosa->rxsize);
		spin_unlock_irqrestore(&cosa->lock, flags);
		goto reject;
	}
	cosa->rxchan = cosa->chan + ((cosa->rxsize & 0xe000) >> 13);
	cosa->rxsize &= 0x1fff;
	spin_unlock_irqrestore(&cosa->lock, flags);

	cosa->rxbuf = NULL;
	if (cosa->rxchan->setup_rx)
		cosa->rxbuf = cosa->rxchan->setup_rx(cosa->rxchan, cosa->rxsize);

	if (!cosa->rxbuf) {
reject:		/* Reject the packet */
		pr_info("cosa%d: rejecting packet on channel %d\n",
			cosa->num, cosa->rxchan->num);
		cosa->rxbuf = cosa->bouncebuf;
	}

	/* start the DMA */
	flags = claim_dma_lock();
	disable_dma(cosa->dma);
	clear_dma_ff(cosa->dma);
	set_dma_mode(cosa->dma, DMA_MODE_READ);
	if (cosa_dma_able(cosa->rxchan, cosa->rxbuf, cosa->rxsize & 0x1fff)) {
		set_dma_addr(cosa->dma, virt_to_bus(cosa->rxbuf));
	} else {
		set_dma_addr(cosa->dma, virt_to_bus(cosa->bouncebuf));
	}
	set_dma_count(cosa->dma, (cosa->rxsize&0x1fff));
	enable_dma(cosa->dma);
	release_dma_lock(flags);
	spin_lock_irqsave(&cosa->lock, flags);
	cosa_putstatus(cosa, SR_RX_DMA_ENA|SR_USR_INT_ENA);
	if (!is_8bit(cosa) && (status & SR_TX_RDY))
		cosa_putdata8(cosa, DRIVER_RX_READY);
#ifdef DEBUG_IO
	debug_status_out(cosa, SR_RX_DMA_ENA|SR_USR_INT_ENA);
	if (!is_8bit(cosa) && (status & SR_TX_RDY))
		debug_data_cmd(cosa, DRIVER_RX_READY);
#endif
	spin_unlock_irqrestore(&cosa->lock, flags);
}

static inline void eot_interrupt(struct cosa_data *cosa, int status)
{
	unsigned long flags, flags1;
	spin_lock_irqsave(&cosa->lock, flags);
	flags1 = claim_dma_lock();
	disable_dma(cosa->dma);
	clear_dma_ff(cosa->dma);
	release_dma_lock(flags1);
	if (test_bit(TXBIT, &cosa->rxtx)) {
		struct channel_data *chan = cosa->chan+cosa->txchan;
		if (chan->tx_done)
			if (chan->tx_done(chan, cosa->txsize))
				clear_bit(chan->num, &cosa->txbitmap);
	} else if (test_bit(RXBIT, &cosa->rxtx)) {
#ifdef DEBUG_DATA
	{
		int i;
		pr_info("cosa%dc%d: done rx(0x%x)",
			cosa->num, cosa->rxchan->num, cosa->rxsize);
		for (i=0; i<cosa->rxsize; i++)
			pr_cont(" %02x", cosa->rxbuf[i]&0xff);
		pr_cont("\n");
	}
#endif
		/* Packet for unknown channel? */
		if (cosa->rxbuf == cosa->bouncebuf)
			goto out;
		if (!cosa_dma_able(cosa->rxchan, cosa->rxbuf, cosa->rxsize))
			memcpy(cosa->rxbuf, cosa->bouncebuf, cosa->rxsize);
		if (cosa->rxchan->rx_done)
			if (cosa->rxchan->rx_done(cosa->rxchan))
				clear_bit(cosa->rxchan->num, &cosa->rxbitmap);
	} else {
		pr_notice("cosa%d: unexpected EOT interrupt\n", cosa->num);
	}
	/*
	 * Clear the RXBIT, TXBIT and IRQBIT (the latest should be
	 * cleared anyway). We should do it as soon as possible
	 * so that we can tell the COSA we are done and to give it a time
	 * for recovery.
	 */
out:
	cosa->rxtx = 0;
	put_driver_status_nolock(cosa);
	spin_unlock_irqrestore(&cosa->lock, flags);
}

static irqreturn_t cosa_interrupt(int irq, void *cosa_)
{
	unsigned status;
	int count = 0;
	struct cosa_data *cosa = cosa_;
again:
	status = cosa_getstatus(cosa);
#ifdef DEBUG_IRQS
	pr_info("cosa%d: got IRQ, status 0x%02x\n", cosa->num, status & 0xff);
#endif
#ifdef DEBUG_IO
	debug_status_in(cosa, status);
#endif
	switch (status & SR_CMD_FROM_SRP_MASK) {
	case SR_DOWN_REQUEST:
		tx_interrupt(cosa, status);
		break;
	case SR_UP_REQUEST:
		rx_interrupt(cosa, status);
		break;
	case SR_END_OF_TRANSFER:
		eot_interrupt(cosa, status);
		break;
	default:
		/* We may be too fast for SRP. Try to wait a bit more. */
		if (count++ < 100) {
			udelay(100);
			goto again;
		}
		pr_info("cosa%d: unknown status 0x%02x in IRQ after %d retries\n",
			cosa->num, status & 0xff, count);
	}
#ifdef DEBUG_IRQS
	if (count)
		pr_info("%s: %d-times got unknown status in IRQ\n",
			cosa->name, count);
	else
		pr_info("%s: returning from IRQ\n", cosa->name);
#endif
	return IRQ_HANDLED;
}


/* ---------- I/O debugging routines ---------- */
/*
 * These routines can be used to monitor COSA/SRP I/O and to printk()
 * the data being transferred on the data and status I/O port in a
 * readable way.
 */

#ifdef DEBUG_IO
static void debug_status_in(struct cosa_data *cosa, int status)
{
	char *s;
	switch (status & SR_CMD_FROM_SRP_MASK) {
	case SR_UP_REQUEST:
		s = "RX_REQ";
		break;
	case SR_DOWN_REQUEST:
		s = "TX_REQ";
		break;
	case SR_END_OF_TRANSFER:
		s = "ET_REQ";
		break;
	default:
		s = "NO_REQ";
		break;
	}
	pr_info("%s: IO: status -> 0x%02x (%s%s%s%s)\n",
		cosa->name,
		status,
		status & SR_USR_RQ ? "USR_RQ|" : "",
		status & SR_TX_RDY ? "TX_RDY|" : "",
		status & SR_RX_RDY ? "RX_RDY|" : "",
		s);
}

static void debug_status_out(struct cosa_data *cosa, int status)
{
	pr_info("%s: IO: status <- 0x%02x (%s%s%s%s%s%s)\n",
		cosa->name,
		status,
		status & SR_RX_DMA_ENA  ? "RXDMA|"  : "!rxdma|",
		status & SR_TX_DMA_ENA  ? "TXDMA|"  : "!txdma|",
		status & SR_RST         ? "RESET|"  : "",
		status & SR_USR_INT_ENA ? "USRINT|" : "!usrint|",
		status & SR_TX_INT_ENA  ? "TXINT|"  : "!txint|",
		status & SR_RX_INT_ENA  ? "RXINT"   : "!rxint");
}

static void debug_data_in(struct cosa_data *cosa, int data)
{
	pr_info("%s: IO: data -> 0x%04x\n", cosa->name, data);
}

static void debug_data_out(struct cosa_data *cosa, int data)
{
	pr_info("%s: IO: data <- 0x%04x\n", cosa->name, data);
}

static void debug_data_cmd(struct cosa_data *cosa, int data)
{
	pr_info("%s: IO: data <- 0x%04x (%s|%s)\n",
		cosa->name, data,
		data & SR_RDY_RCV ? "RX_RDY" : "!rx_rdy",
		data & SR_RDY_SND ? "TX_RDY" : "!tx_rdy");
}
#endif

/* EOF -- this file has not been truncated */