aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/cdrom/optcd.c
blob: 351a01dd503a3ceea3073f0c6dd31acd82e4c70f (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
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
/*	linux/drivers/cdrom/optcd.c - Optics Storage 8000 AT CDROM driver
	$Id: optcd.c,v 1.11 1997/01/26 07:13:00 davem Exp $

	Copyright (C) 1995 Leo Spiekman (spiekman@dutette.et.tudelft.nl)


	Based on Aztech CD268 CDROM driver by Werner Zimmermann and preworks
	by Eberhard Moenkeberg (emoenke@gwdg.de). 

	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, 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.
*/

/*	Revision history


	14-5-95		v0.0	Plays sound tracks. No reading of data CDs yet.
				Detection of disk change doesn't work.
	21-5-95		v0.1	First ALPHA version. CD can be mounted. The
				device major nr is borrowed from the Aztech
				driver. Speed is around 240 kb/s, as measured
				with "time dd if=/dev/cdrom of=/dev/null \
				bs=2048 count=4096".
	24-6-95		v0.2	Reworked the #defines for the command codes
				and the like, as well as the structure of
				the hardware communication protocol, to
				reflect the "official" documentation, kindly
				supplied by C.K. Tan, Optics Storage Pte. Ltd.
				Also tidied up the state machine somewhat.
	28-6-95		v0.3	Removed the ISP-16 interface code, as this
				should go into its own driver. The driver now
				has its own major nr.
				Disk change detection now seems to work, too.
				This version became part of the standard
				kernel as of version 1.3.7
	24-9-95		v0.4	Re-inserted ISP-16 interface code which I
				copied from sjcd.c, with a few changes.
				Updated README.optcd. Submitted for
				inclusion in 1.3.21
	29-9-95		v0.4a	Fixed bug that prevented compilation as module
	25-10-95	v0.5	Started multisession code. Implementation
				copied from Werner Zimmermann, who copied it
				from Heiko Schlittermann's mcdx.
	17-1-96		v0.6	Multisession works; some cleanup too.
	18-4-96		v0.7	Increased some timing constants;
				thanks to Luke McFarlane. Also tidied up some
				printk behaviour. ISP16 initialization
				is now handled by a separate driver.
				
	09-11-99 	  	Make kernel-parameter implementation work with 2.3.x 
	                 	Removed init_module & cleanup_module in favor of 
			 	module_init & module_exit.
			 	Torben Mathiasen <tmm@image.dk>
*/

/* Includes */


#include <linux/module.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/init.h>

#include <asm/io.h>
#include <linux/blkdev.h>

#include <linux/cdrom.h>
#include "optcd.h"

#include <asm/uaccess.h>

#define MAJOR_NR OPTICS_CDROM_MAJOR
#define QUEUE (opt_queue)
#define CURRENT elv_next_request(opt_queue)


/* Debug support */


/* Don't forget to add new debug flags here. */
#if DEBUG_DRIVE_IF | DEBUG_VFS | DEBUG_CONV | DEBUG_TOC | \
    DEBUG_BUFFERS | DEBUG_REQUEST | DEBUG_STATE | DEBUG_MULTIS
#define DEBUG(x) debug x
static void debug(int debug_this, const char* fmt, ...)
{
	char s[1024];
	va_list args;

	if (!debug_this)
		return;

	va_start(args, fmt);
	vsprintf(s, fmt, args);
	printk(KERN_DEBUG "optcd: %s\n", s);
	va_end(args);
}
#else
#define DEBUG(x)
#endif


/* Drive hardware/firmware characteristics
   Identifiers in accordance with Optics Storage documentation */


#define optcd_port optcd			/* Needed for the modutils. */
static short optcd_port = OPTCD_PORTBASE;	/* I/O base of drive. */
module_param(optcd_port, short, 0);
/* Drive registers, read */
#define DATA_PORT	optcd_port	/* Read data/status */
#define STATUS_PORT	optcd_port+1	/* Indicate data/status availability */

/* Drive registers, write */
#define COMIN_PORT	optcd_port	/* For passing command/parameter */
#define RESET_PORT	optcd_port+1	/* Write anything and wait 0.5 sec */
#define HCON_PORT	optcd_port+2	/* Host Xfer Configuration */


/* Command completion/status read from DATA register */
#define ST_DRVERR		0x80
#define ST_DOOR_OPEN		0x40
#define ST_MIXEDMODE_DISK	0x20
#define ST_MODE_BITS		0x1c
#define ST_M_STOP		0x00
#define ST_M_READ		0x04
#define ST_M_AUDIO		0x04
#define ST_M_PAUSE		0x08
#define ST_M_INITIAL		0x0c
#define ST_M_ERROR		0x10
#define ST_M_OTHERS		0x14
#define	ST_MODE2TRACK		0x02
#define	ST_DSK_CHG		0x01
#define ST_L_LOCK		0x01
#define ST_CMD_OK		0x00
#define ST_OP_OK		0x01
#define ST_PA_OK		0x02
#define ST_OP_ERROR		0x05
#define ST_PA_ERROR		0x06


/* Error codes (appear as command completion code from DATA register) */
/* Player related errors */
#define ERR_ILLCMD	0x11	/* Illegal command to player module */
#define ERR_ILLPARM	0x12	/* Illegal parameter to player module */
#define ERR_SLEDGE	0x13
#define ERR_FOCUS	0x14
#define ERR_MOTOR	0x15
#define ERR_RADIAL	0x16
#define ERR_PLL		0x17	/* PLL lock error */
#define ERR_SUB_TIM	0x18	/* Subcode timeout error */
#define ERR_SUB_NF	0x19	/* Subcode not found error */
#define ERR_TRAY	0x1a
#define ERR_TOC		0x1b	/* Table of Contents read error */
#define ERR_JUMP	0x1c
/* Data errors */
#define ERR_MODE	0x21
#define ERR_FORM	0x22
#define ERR_HEADADDR	0x23	/* Header Address not found */
#define ERR_CRC		0x24
#define ERR_ECC		0x25	/* Uncorrectable ECC error */
#define ERR_CRC_UNC	0x26	/* CRC error and uncorrectable error */
#define ERR_ILLBSYNC	0x27	/* Illegal block sync error */
#define ERR_VDST	0x28	/* VDST not found */
/* Timeout errors */
#define ERR_READ_TIM	0x31	/* Read timeout error */
#define ERR_DEC_STP	0x32	/* Decoder stopped */
#define ERR_DEC_TIM	0x33	/* Decoder interrupt timeout error */
/* Function abort codes */
#define ERR_KEY		0x41	/* Key -Detected abort */
#define ERR_READ_FINISH	0x42	/* Read Finish */
/* Second Byte diagnostic codes */
#define ERR_NOBSYNC	0x01	/* No block sync */
#define ERR_SHORTB	0x02	/* Short block */
#define ERR_LONGB	0x03	/* Long block */
#define ERR_SHORTDSP	0x04	/* Short DSP word */
#define ERR_LONGDSP	0x05	/* Long DSP word */


/* Status availability flags read from STATUS register */
#define FL_EJECT	0x20
#define FL_WAIT		0x10	/* active low */
#define FL_EOP		0x08	/* active low */
#define FL_STEN		0x04	/* Status available when low */
#define FL_DTEN		0x02	/* Data available when low */
#define FL_DRQ		0x01	/* active low */
#define FL_RESET	0xde	/* These bits are high after a reset */
#define FL_STDT		(FL_STEN|FL_DTEN)


/* Transfer mode, written to HCON register */
#define HCON_DTS	0x08
#define HCON_SDRQB	0x04
#define HCON_LOHI	0x02
#define HCON_DMA16	0x01


/* Drive command set, written to COMIN register */
/* Quick response commands */
#define COMDRVST	0x20	/* Drive Status Read */
#define COMERRST	0x21	/* Error Status Read */
#define COMIOCTLISTAT	0x22	/* Status Read; reset disk changed bit */
#define COMINITSINGLE	0x28	/* Initialize Single Speed */
#define COMINITDOUBLE	0x29	/* Initialize Double Speed */
#define COMUNLOCK	0x30	/* Unlock */
#define COMLOCK		0x31	/* Lock */
#define COMLOCKST	0x32	/* Lock/Unlock Status */
#define COMVERSION	0x40	/* Get Firmware Revision */
#define COMVOIDREADMODE	0x50	/* Void Data Read Mode */
/* Read commands */
#define COMFETCH	0x60	/* Prefetch Data */
#define COMREAD		0x61	/* Read */
#define COMREADRAW	0x62	/* Read Raw Data */
#define COMREADALL	0x63	/* Read All 2646 Bytes */
/* Player control commands */
#define COMLEADIN	0x70	/* Seek To Lead-in */
#define COMSEEK		0x71	/* Seek */
#define COMPAUSEON	0x80	/* Pause On */
#define COMPAUSEOFF	0x81	/* Pause Off */
#define COMSTOP		0x82	/* Stop */
#define COMOPEN		0x90	/* Open Tray Door */
#define COMCLOSE	0x91	/* Close Tray Door */
#define COMPLAY		0xa0	/* Audio Play */
#define COMPLAY_TNO	0xa2	/* Audio Play By Track Number */
#define COMSUBQ		0xb0	/* Read Sub-q Code */
#define COMLOCATION	0xb1	/* Read Head Position */
/* Audio control commands */
#define COMCHCTRL	0xc0	/* Audio Channel Control */
/* Miscellaneous (test) commands */
#define COMDRVTEST	0xd0	/* Write Test Bytes */
#define COMTEST		0xd1	/* Diagnostic Test */

/* Low level drive interface. Only here we do actual I/O
   Waiting for status / data available */


/* Busy wait until FLAG goes low. Return 0 on timeout. */
static inline int flag_low(int flag, unsigned long timeout)
{
	int flag_high;
	unsigned long count = 0;

	while ((flag_high = (inb(STATUS_PORT) & flag)))
		if (++count >= timeout)
			break;

	DEBUG((DEBUG_DRIVE_IF, "flag_low 0x%x count %ld%s",
		flag, count, flag_high ? " timeout" : ""));
	return !flag_high;
}


/* Timed waiting for status or data */
static int sleep_timeout;	/* max # of ticks to sleep */
static DECLARE_WAIT_QUEUE_HEAD(waitq);
static void sleep_timer(unsigned long data);
static struct timer_list delay_timer = TIMER_INITIALIZER(sleep_timer, 0, 0);
static DEFINE_SPINLOCK(optcd_lock);
static struct request_queue *opt_queue;

/* Timer routine: wake up when desired flag goes low,
   or when timeout expires. */
static void sleep_timer(unsigned long data)
{
	int flags = inb(STATUS_PORT) & FL_STDT;

	if (flags == FL_STDT && --sleep_timeout > 0) {
		mod_timer(&delay_timer, jiffies + HZ/100); /* multi-statement macro */
	} else
		wake_up(&waitq);
}


/* Sleep until FLAG goes low. Return 0 on timeout or wrong flag low. */
static int sleep_flag_low(int flag, unsigned long timeout)
{
	int flag_high;

	DEBUG((DEBUG_DRIVE_IF, "sleep_flag_low"));

	sleep_timeout = timeout;
	flag_high = inb(STATUS_PORT) & flag;
	if (flag_high && sleep_timeout > 0) {
		mod_timer(&delay_timer, jiffies + HZ/100);
		sleep_on(&waitq);
		flag_high = inb(STATUS_PORT) & flag;
	}

	DEBUG((DEBUG_DRIVE_IF, "flag 0x%x count %ld%s",
		flag, timeout, flag_high ? " timeout" : ""));
	return !flag_high;
}

/* Low level drive interface. Only here we do actual I/O
   Sending commands and parameters */


/* Errors in the command protocol */
#define ERR_IF_CMD_TIMEOUT	0x100
#define ERR_IF_ERR_TIMEOUT	0x101
#define ERR_IF_RESP_TIMEOUT	0x102
#define ERR_IF_DATA_TIMEOUT	0x103
#define ERR_IF_NOSTAT		0x104


/* Send command code. Return <0 indicates error */
static int send_cmd(int cmd)
{
	unsigned char ack;

	DEBUG((DEBUG_DRIVE_IF, "sending command 0x%02x\n", cmd));

	outb(HCON_DTS, HCON_PORT);	/* Enable Suspend Data Transfer */
	outb(cmd, COMIN_PORT);		/* Send command code */
	if (!flag_low(FL_STEN, BUSY_TIMEOUT))	/* Wait for status */
		return -ERR_IF_CMD_TIMEOUT;
	ack = inb(DATA_PORT);		/* read command acknowledge */
	outb(HCON_SDRQB, HCON_PORT);	/* Disable Suspend Data Transfer */
	return ack==ST_OP_OK ? 0 : -ack;
}


/* Send command parameters. Return <0 indicates error */
static int send_params(struct cdrom_msf *params)
{
	unsigned char ack;

	DEBUG((DEBUG_DRIVE_IF, "sending parameters"
		" %02x:%02x:%02x"
		" %02x:%02x:%02x",
		params->cdmsf_min0,
		params->cdmsf_sec0,
		params->cdmsf_frame0,
		params->cdmsf_min1,
		params->cdmsf_sec1,
		params->cdmsf_frame1));

	outb(params->cdmsf_min0, COMIN_PORT);
	outb(params->cdmsf_sec0, COMIN_PORT);
	outb(params->cdmsf_frame0, COMIN_PORT);
	outb(params->cdmsf_min1, COMIN_PORT);
	outb(params->cdmsf_sec1, COMIN_PORT);
	outb(params->cdmsf_frame1, COMIN_PORT);
	if (!flag_low(FL_STEN, BUSY_TIMEOUT))	/* Wait for status */
		return -ERR_IF_CMD_TIMEOUT;
	ack = inb(DATA_PORT);		/* read command acknowledge */
	return ack==ST_PA_OK ? 0 : -ack;
}


/* Send parameters for SEEK command. Return <0 indicates error */
static int send_seek_params(struct cdrom_msf *params)
{
	unsigned char ack;

	DEBUG((DEBUG_DRIVE_IF, "sending seek parameters"
		" %02x:%02x:%02x",
		params->cdmsf_min0,
		params->cdmsf_sec0,
		params->cdmsf_frame0));

	outb(params->cdmsf_min0, COMIN_PORT);
	outb(params->cdmsf_sec0, COMIN_PORT);
	outb(params->cdmsf_frame0, COMIN_PORT);
	if (!flag_low(FL_STEN, BUSY_TIMEOUT))	/* Wait for status */
		return -ERR_IF_CMD_TIMEOUT;
	ack = inb(DATA_PORT);		/* read command acknowledge */
	return ack==ST_PA_OK ? 0 : -ack;
}


/* Wait for command execution status. Choice between busy waiting
   and sleeping. Return value <0 indicates timeout. */
static inline int get_exec_status(int busy_waiting)
{
	unsigned char exec_status;

	if (busy_waiting
	    ? !flag_low(FL_STEN, BUSY_TIMEOUT)
	    : !sleep_flag_low(FL_STEN, SLEEP_TIMEOUT))
		return -ERR_IF_CMD_TIMEOUT;

	exec_status = inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "returned exec status 0x%02x", exec_status));
	return exec_status;
}


/* Wait busy for extra byte of data that a command returns.
   Return value <0 indicates timeout. */
static inline int get_data(int short_timeout)
{
	unsigned char data;

	if (!flag_low(FL_STEN, short_timeout ? FAST_TIMEOUT : BUSY_TIMEOUT))
		return -ERR_IF_DATA_TIMEOUT;

	data = inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "returned data 0x%02x", data));
	return data;
}


/* Returns 0 if failed */
static int reset_drive(void)
{
	unsigned long count = 0;
	int flags;

	DEBUG((DEBUG_DRIVE_IF, "reset drive"));

	outb(0, RESET_PORT);
	while (++count < RESET_WAIT)
		inb(DATA_PORT);

	count = 0;
	while ((flags = (inb(STATUS_PORT) & FL_RESET)) != FL_RESET)
		if (++count >= BUSY_TIMEOUT)
			break;

	DEBUG((DEBUG_DRIVE_IF, "reset %s",
		flags == FL_RESET ? "succeeded" : "failed"));

	if (flags != FL_RESET)
		return 0;		/* Reset failed */
	outb(HCON_SDRQB, HCON_PORT);	/* Disable Suspend Data Transfer */
	return 1;			/* Reset succeeded */
}


/* Facilities for asynchronous operation */

/* Read status/data availability flags FL_STEN and FL_DTEN */
static inline int stdt_flags(void)
{
	return inb(STATUS_PORT) & FL_STDT;
}


/* Fetch status that has previously been waited for. <0 means not available */
static inline int fetch_status(void)
{
	unsigned char status;

	if (inb(STATUS_PORT) & FL_STEN)
		return -ERR_IF_NOSTAT;

	status = inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "fetched exec status 0x%02x", status));
	return status;
}


/* Fetch data that has previously been waited for. */
static inline void fetch_data(char *buf, int n)
{
	insb(DATA_PORT, buf, n);
	DEBUG((DEBUG_DRIVE_IF, "fetched 0x%x bytes", n));
}


/* Flush status and data fifos */
static inline void flush_data(void)
{
	while ((inb(STATUS_PORT) & FL_STDT) != FL_STDT)
		inb(DATA_PORT);
	DEBUG((DEBUG_DRIVE_IF, "flushed fifos"));
}

/* Command protocol */


/* Send a simple command and wait for response. Command codes < COMFETCH
   are quick response commands */
static inline int exec_cmd(int cmd)
{
	int ack = send_cmd(cmd);
	if (ack < 0)
		return ack;
	return get_exec_status(cmd < COMFETCH);
}


/* Send a command with parameters. Don't wait for the response,
 * which consists of data blocks read from the CD. */
static inline int exec_read_cmd(int cmd, struct cdrom_msf *params)
{
	int ack = send_cmd(cmd);
	if (ack < 0)
		return ack;
	return send_params(params);
}


/* Send a seek command with parameters and wait for response */
static inline int exec_seek_cmd(int cmd, struct cdrom_msf *params)
{
	int ack = send_cmd(cmd);
	if (ack < 0)
		return ack;
	ack = send_seek_params(params);
	if (ack < 0)
		return ack;
	return 0;
}


/* Send a command with parameters and wait for response */
static inline int exec_long_cmd(int cmd, struct cdrom_msf *params)
{
	int ack = exec_read_cmd(cmd, params);
	if (ack < 0)
		return ack;
	return get_exec_status(0);
}

/* Address conversion routines */


/* Binary to BCD (2 digits) */
static inline void single_bin2bcd(u_char *p)
{
	DEBUG((DEBUG_CONV, "bin2bcd %02d", *p));
	*p = (*p % 10) | ((*p / 10) << 4);
}


/* Convert entire msf struct */
static void bin2bcd(struct cdrom_msf *msf)
{
	single_bin2bcd(&msf->cdmsf_min0);
	single_bin2bcd(&msf->cdmsf_sec0);
	single_bin2bcd(&msf->cdmsf_frame0);
	single_bin2bcd(&msf->cdmsf_min1);
	single_bin2bcd(&msf->cdmsf_sec1);
	single_bin2bcd(&msf->cdmsf_frame1);
}


/* Linear block address to minute, second, frame form */
#define CD_FPM	(CD_SECS * CD_FRAMES)	/* frames per minute */

static void lba2msf(int lba, struct cdrom_msf *msf)
{
	DEBUG((DEBUG_CONV, "lba2msf %d", lba));
	lba += CD_MSF_OFFSET;
	msf->cdmsf_min0 = lba / CD_FPM; lba %= CD_FPM;
	msf->cdmsf_sec0 = lba / CD_FRAMES;
	msf->cdmsf_frame0 = lba % CD_FRAMES;
	msf->cdmsf_min1 = 0;
	msf->cdmsf_sec1 = 0;
	msf->cdmsf_frame1 = 0;
	bin2bcd(msf);
}


/* Two BCD digits to binary */
static inline u_char bcd2bin(u_char bcd)
{
	DEBUG((DEBUG_CONV, "bcd2bin %x%02x", bcd));
	return (bcd >> 4) * 10 + (bcd & 0x0f);
}


static void msf2lba(union cdrom_addr *addr)
{
	addr->lba = addr->msf.minute * CD_FPM
	            + addr->msf.second * CD_FRAMES
	            + addr->msf.frame - CD_MSF_OFFSET;
}


/* Minute, second, frame address BCD to binary or to linear address,
   depending on MODE */
static void msf_bcd2bin(union cdrom_addr *addr)
{
	addr->msf.minute = bcd2bin(addr->msf.minute);
	addr->msf.second = bcd2bin(addr->msf.second);
	addr->msf.frame = bcd2bin(addr->msf.frame);
}

/* High level drive commands */


static int audio_status = CDROM_AUDIO_NO_STATUS;
static char toc_uptodate = 0;
static char disk_changed = 1;

/* Get drive status, flagging completion of audio play and disk changes. */
static int drive_status(void)
{
	int status;

	status = exec_cmd(COMIOCTLISTAT);
	DEBUG((DEBUG_DRIVE_IF, "IOCTLISTAT: %03x", status));
	if (status < 0)
		return status;
	if (status == 0xff)	/* No status available */
		return -ERR_IF_NOSTAT;

	if (((status & ST_MODE_BITS) != ST_M_AUDIO) &&
		(audio_status == CDROM_AUDIO_PLAY)) {
		audio_status = CDROM_AUDIO_COMPLETED;
	}

	if (status & ST_DSK_CHG) {
		toc_uptodate = 0;
		disk_changed = 1;
		audio_status = CDROM_AUDIO_NO_STATUS;
	}

	return status;
}


/* Read the current Q-channel info. Also used for reading the
   table of contents. qp->cdsc_format must be set on entry to
   indicate the desired address format */
static int get_q_channel(struct cdrom_subchnl *qp)
{
	int status, d1, d2, d3, d4, d5, d6, d7, d8, d9, d10;

	status = drive_status();
	if (status < 0)
		return status;
	qp->cdsc_audiostatus = audio_status;

	status = exec_cmd(COMSUBQ);
	if (status < 0)
		return status;

	d1 = get_data(0);
	if (d1 < 0)
		return d1;
	qp->cdsc_adr = d1;
	qp->cdsc_ctrl = d1 >> 4;

	d2 = get_data(0);
	if (d2 < 0)
		return d2;
	qp->cdsc_trk = bcd2bin(d2);

	d3 = get_data(0);
	if (d3 < 0)
		return d3;
	qp->cdsc_ind = bcd2bin(d3);

	d4 = get_data(0);
	if (d4 < 0)
		return d4;
	qp->cdsc_reladdr.msf.minute = d4;

	d5 = get_data(0);
	if (d5 < 0)
		return d5;
	qp->cdsc_reladdr.msf.second = d5;

	d6 = get_data(0);
	if (d6 < 0)
		return d6;
	qp->cdsc_reladdr.msf.frame = d6;

	d7 = get_data(0);
	if (d7 < 0)
		return d7;
	/* byte not used */

	d8 = get_data(0);
	if (d8 < 0)
		return d8;
	qp->cdsc_absaddr.msf.minute = d8;

	d9 = get_data(0);
	if (d9 < 0)
		return d9;
	qp->cdsc_absaddr.msf.second = d9;

	d10 = get_data(0);
	if (d10 < 0)
		return d10;
	qp->cdsc_absaddr.msf.frame = d10;

	DEBUG((DEBUG_TOC, "%02x %02x %02x %02x %02x %02x %02x %02x %02x %02x",
		d1, d2, d3, d4, d5, d6, d7, d8, d9, d10));

	msf_bcd2bin(&qp->cdsc_absaddr);
	msf_bcd2bin(&qp->cdsc_reladdr);
	if (qp->cdsc_format == CDROM_LBA) {
		msf2lba(&qp->cdsc_absaddr);
		msf2lba(&qp->cdsc_reladdr);
	}

	return 0;
}

/* Table of contents handling */


/* Errors in table of contents */
#define ERR_TOC_MISSINGINFO	0x120
#define ERR_TOC_MISSINGENTRY	0x121


struct cdrom_disk_info {
	unsigned char		first;
	unsigned char		last;
	struct cdrom_msf0	disk_length;
	struct cdrom_msf0	first_track;
	/* Multisession info: */
	unsigned char		next;
	struct cdrom_msf0	next_session;
	struct cdrom_msf0	last_session;
	unsigned char		multi;
	unsigned char		xa;
	unsigned char		audio;
};
static struct cdrom_disk_info disk_info;

#define MAX_TRACKS		111
static struct cdrom_subchnl toc[MAX_TRACKS];

#define QINFO_FIRSTTRACK	100 /* bcd2bin(0xa0) */
#define QINFO_LASTTRACK		101 /* bcd2bin(0xa1) */
#define QINFO_DISKLENGTH	102 /* bcd2bin(0xa2) */
#define QINFO_NEXTSESSION	110 /* bcd2bin(0xb0) */

#define I_FIRSTTRACK	0x01
#define I_LASTTRACK	0x02
#define I_DISKLENGTH	0x04
#define I_NEXTSESSION	0x08
#define I_ALL	(I_FIRSTTRACK | I_LASTTRACK | I_DISKLENGTH)


#if DEBUG_TOC
static void toc_debug_info(int i)
{
	printk(KERN_DEBUG "#%3d ctl %1x, adr %1x, track %2d index %3d"
		"  %2d:%02d.%02d %2d:%02d.%02d\n",
		i, toc[i].cdsc_ctrl, toc[i].cdsc_adr,
		toc[i].cdsc_trk, toc[i].cdsc_ind,
		toc[i].cdsc_reladdr.msf.minute,
		toc[i].cdsc_reladdr.msf.second,
		toc[i].cdsc_reladdr.msf.frame,
		toc[i].cdsc_absaddr.msf.minute,
		toc[i].cdsc_absaddr.msf.second,
		toc[i].cdsc_absaddr.msf.frame);
}
#endif


static int read_toc(void)
{
	int status, limit, count;
	unsigned char got_info = 0;
	struct cdrom_subchnl q_info;
#if DEBUG_TOC
	int i;
#endif

	DEBUG((DEBUG_TOC, "starting read_toc"));

	count = 0;
	for (limit = 60; limit > 0; limit--) {
		int index;

		q_info.cdsc_format = CDROM_MSF;
		status = get_q_channel(&q_info);
		if (status < 0)
			return status;

		index = q_info.cdsc_ind;
		if (index > 0 && index < MAX_TRACKS
		    && q_info.cdsc_trk == 0 && toc[index].cdsc_ind == 0) {
			toc[index] = q_info;
			DEBUG((DEBUG_TOC, "got %d", index));
			if (index < 100)
				count++;

			switch (q_info.cdsc_ind) {
			case QINFO_FIRSTTRACK:
				got_info |= I_FIRSTTRACK;
				break;
			case QINFO_LASTTRACK:
				got_info |= I_LASTTRACK;
				break;
			case QINFO_DISKLENGTH:
				got_info |= I_DISKLENGTH;
				break;
			case QINFO_NEXTSESSION:
				got_info |= I_NEXTSESSION;
				break;
			}
		}

		if ((got_info & I_ALL) == I_ALL
		    && toc[QINFO_FIRSTTRACK].cdsc_absaddr.msf.minute + count
		       >= toc[QINFO_LASTTRACK].cdsc_absaddr.msf.minute + 1)
			break;
	}

	/* Construct disk_info from TOC */
	if (disk_info.first == 0) {
		disk_info.first = toc[QINFO_FIRSTTRACK].cdsc_absaddr.msf.minute;
		disk_info.first_track.minute =
			toc[disk_info.first].cdsc_absaddr.msf.minute;
		disk_info.first_track.second =
			toc[disk_info.first].cdsc_absaddr.msf.second;
		disk_info.first_track.frame =
			toc[disk_info.first].cdsc_absaddr.msf.frame;
	}
	disk_info.last = toc[QINFO_LASTTRACK].cdsc_absaddr.msf.minute;
	disk_info.disk_length.minute =
			toc[QINFO_DISKLENGTH].cdsc_absaddr.msf.minute;
	disk_info.disk_length.second =
			toc[QINFO_DISKLENGTH].cdsc_absaddr.msf.second-2;
	disk_info.disk_length.frame =
			toc[QINFO_DISKLENGTH].cdsc_absaddr.msf.frame;
	disk_info.next_session.minute =
			toc[QINFO_NEXTSESSION].cdsc_reladdr.msf.minute;
	disk_info.next_session.second =
			toc[QINFO_NEXTSESSION].cdsc_reladdr.msf.second;
	disk_info.next_session.frame =
			toc[QINFO_NEXTSESSION].cdsc_reladdr.msf.frame;
	disk_info.next = toc[QINFO_FIRSTTRACK].cdsc_absaddr.msf.minute;
	disk_info.last_session.minute =
			toc[disk_info.next].cdsc_absaddr.msf.minute;
	disk_info.last_session.second =
			toc[disk_info.next].cdsc_absaddr.msf.second;
	disk_info.last_session.frame =
			toc[disk_info.next].cdsc_absaddr.msf.frame;
	toc[disk_info.last + 1].cdsc_absaddr.msf.minute =
			disk_info.disk_length.minute;
	toc[disk_info.last + 1].cdsc_absaddr.msf.second =
			disk_info.disk_length.second;
	toc[disk_info.last + 1].cdsc_absaddr.msf.frame =
			disk_info.disk_length.frame;
#if DEBUG_TOC
	for (i = 1; i <= disk_info.last + 1; i++)
		toc_debug_info(i);
	toc_debug_info(QINFO_FIRSTTRACK);
	toc_debug_info(QINFO_LASTTRACK);
	toc_debug_info(QINFO_DISKLENGTH);
	toc_debug_info(QINFO_NEXTSESSION);
#endif

	DEBUG((DEBUG_TOC, "exiting read_toc, got_info %x, count %d",
		got_info, count));
	if ((got_info & I_ALL) != I_ALL
	    || toc[QINFO_FIRSTTRACK].cdsc_absaddr.msf.minute + count
	       < toc[QINFO_LASTTRACK].cdsc_absaddr.msf.minute + 1)
		return -ERR_TOC_MISSINGINFO;
	return 0;
}


#ifdef MULTISESSION
static int get_multi_disk_info(void)
{
	int sessions, status;
	struct cdrom_msf multi_index;


	for (sessions = 2; sessions < 10 /* %%for now */; sessions++) {
		int count;

		for (count = 100; count < MAX_TRACKS; count++) 
			toc[count].cdsc_ind = 0;

		multi_index.cdmsf_min0 = disk_info.next_session.minute;
		multi_index.cdmsf_sec0 = disk_info.next_session.second;
		multi_index.cdmsf_frame0 = disk_info.next_session.frame;
		if (multi_index.cdmsf_sec0 >= 20)
			multi_index.cdmsf_sec0 -= 20;
		else {
			multi_index.cdmsf_sec0 += 40;
			multi_index.cdmsf_min0--;
		}
		DEBUG((DEBUG_MULTIS, "Try %d: %2d:%02d.%02d", sessions,
			multi_index.cdmsf_min0,
			multi_index.cdmsf_sec0,
			multi_index.cdmsf_frame0));
		bin2bcd(&multi_index);
		multi_index.cdmsf_min1 = 0;
		multi_index.cdmsf_sec1 = 0;
		multi_index.cdmsf_frame1 = 1;

		status = exec_read_cmd(COMREAD, &multi_index);
		if (status < 0) {
			DEBUG((DEBUG_TOC, "exec_read_cmd COMREAD: %02x",
				-status));
			break;
		}
		status = sleep_flag_low(FL_DTEN, MULTI_SEEK_TIMEOUT) ?
				0 : -ERR_TOC_MISSINGINFO;
		flush_data();
		if (status < 0) {
			DEBUG((DEBUG_TOC, "sleep_flag_low: %02x", -status));
			break;
		}

		status = read_toc();
		if (status < 0) {
			DEBUG((DEBUG_TOC, "read_toc: %02x", -status));
			break;
		}

		disk_info.multi = 1;
	}

	exec_cmd(COMSTOP);

	if (status < 0)
		return -EIO;
	return 0;
}
#endif /* MULTISESSION */


static int update_toc(void)
{
	int status, count;

	if (toc_uptodate)
		return 0;

	DEBUG((DEBUG_TOC, "starting update_toc"));

	disk_info.first = 0;
	for (count = 0; count < MAX_TRACKS; count++) 
		toc[count].cdsc_ind = 0;

	status = exec_cmd(COMLEADIN);
	if (status < 0)
		return -EIO;

	status = read_toc();
	if (status < 0) {
		DEBUG((DEBUG_TOC, "read_toc: %02x", -status));
		return -EIO;
	}

        /* Audio disk detection. Look at first track. */
	disk_info.audio =
		(toc[disk_info.first].cdsc_ctrl & CDROM_DATA_TRACK) ? 0 : 1;

	/* XA detection */
	disk_info.xa = drive_status() & ST_MODE2TRACK;

	/* Multisession detection: if we want this, define MULTISESSION */
	disk_info.multi = 0;
#ifdef MULTISESSION
 	if (disk_info.xa)
		get_multi_disk_info();	/* Here disk_info.multi is set */
#endif /* MULTISESSION */
	if (disk_info.multi)
		printk(KERN_WARNING "optcd: Multisession support experimental, "
			"see Documentation/cdrom/optcd\n");

	DEBUG((DEBUG_TOC, "exiting update_toc"));

	toc_uptodate = 1;
	return 0;
}

/* Request handling */

static int current_valid(void)
{
        return CURRENT &&
		CURRENT->cmd == READ &&
		CURRENT->sector != -1;
}

/* Buffers for block size conversion. */
#define NOBUF		-1

static char buf[CD_FRAMESIZE * N_BUFS];
static volatile int buf_bn[N_BUFS], next_bn;
static volatile int buf_in = 0, buf_out = NOBUF;

static inline void opt_invalidate_buffers(void)
{
	int i;

	DEBUG((DEBUG_BUFFERS, "executing opt_invalidate_buffers"));

	for (i = 0; i < N_BUFS; i++)
		buf_bn[i] = NOBUF;
	buf_out = NOBUF;
}


/* Take care of the different block sizes between cdrom and Linux.
   When Linux gets variable block sizes this will probably go away. */
static void transfer(void)
{
#if DEBUG_BUFFERS | DEBUG_REQUEST
	printk(KERN_DEBUG "optcd: executing transfer\n");
#endif

	if (!current_valid())
		return;
	while (CURRENT -> nr_sectors) {
		int bn = CURRENT -> sector / 4;
		int i, offs, nr_sectors;
		for (i = 0; i < N_BUFS && buf_bn[i] != bn; ++i);

		DEBUG((DEBUG_REQUEST, "found %d", i));

		if (i >= N_BUFS) {
			buf_out = NOBUF;
			break;
		}

		offs = (i * 4 + (CURRENT -> sector & 3)) * 512;
		nr_sectors = 4 - (CURRENT -> sector & 3);

		if (buf_out != i) {
			buf_out = i;
			if (buf_bn[i] != bn) {
				buf_out = NOBUF;
				continue;
			}
		}

		if (nr_sectors > CURRENT -> nr_sectors)
			nr_sectors = CURRENT -> nr_sectors;
		memcpy(CURRENT -> buffer, buf + offs, nr_sectors * 512);
		CURRENT -> nr_sectors -= nr_sectors;
		CURRENT -> sector += nr_sectors;
		CURRENT -> buffer += nr_sectors * 512;
	}
}


/* State machine for reading disk blocks */

enum state_e {
	S_IDLE,		/* 0 */
	S_START,	/* 1 */
	S_READ,		/* 2 */
	S_DATA,		/* 3 */
	S_STOP,		/* 4 */
	S_STOPPING	/* 5 */
};

static volatile enum state_e state = S_IDLE;
#if DEBUG_STATE
static volatile enum state_e state_old = S_STOP;
static volatile int flags_old = 0;
static volatile long state_n = 0;
#endif


/* Used as mutex to keep do_optcd_request (and other processes calling
   ioctl) out while some process is inside a VFS call.
   Reverse is accomplished by checking if state = S_IDLE upon entry
   of opt_ioctl and opt_media_change. */
static int in_vfs = 0;


static volatile int transfer_is_active = 0;
static volatile int error = 0;	/* %% do something with this?? */
static int tries;		/* ibid?? */
static int timeout = 0;

static void poll(unsigned long data);
static struct timer_list req_timer = {.function = poll};


static void poll(unsigned long data)
{
	static volatile int read_count = 1;
	int flags;
	int loop_again = 1;
	int status = 0;
	int skip = 0;

	if (error) {
		printk(KERN_ERR "optcd: I/O error 0x%02x\n", error);
		opt_invalidate_buffers();
		if (!tries--) {
			printk(KERN_ERR "optcd: read block %d failed;"
				" Giving up\n", next_bn);
			if (transfer_is_active)
				loop_again = 0;
			if (current_valid())
				end_request(CURRENT, 0);
			tries = 5;
		}
		error = 0;
		state = S_STOP;
	}

	while (loop_again)
	{
		loop_again = 0; /* each case must flip this back to 1 if we want
		                 to come back up here */

#if DEBUG_STATE
		if (state == state_old)
			state_n++;
		else {
			state_old = state;
			if (++state_n > 1)
				printk(KERN_DEBUG "optcd: %ld times "
					"in previous state\n", state_n);
			printk(KERN_DEBUG "optcd: state %d\n", state);
			state_n = 0;
		}
#endif

		switch (state) {
		case S_IDLE:
			return;
		case S_START:
			if (in_vfs)
				break;
			if (send_cmd(COMDRVST)) {
				state = S_IDLE;
				while (current_valid())
					end_request(CURRENT, 0);
				return;
			}
			state = S_READ;
			timeout = READ_TIMEOUT;
			break;
		case S_READ: {
			struct cdrom_msf msf;
			if (!skip) {
				status = fetch_status();
				if (status < 0)
					break;
				if (status & ST_DSK_CHG) {
					toc_uptodate = 0;
					opt_invalidate_buffers();
				}
			}
			skip = 0;
			if ((status & ST_DOOR_OPEN) || (status & ST_DRVERR)) {
				toc_uptodate = 0;
				opt_invalidate_buffers();
				printk(KERN_WARNING "optcd: %s\n",
					(status & ST_DOOR_OPEN)
					? "door open"
					: "disk removed");
				state = S_IDLE;
				while (current_valid())
					end_request(CURRENT, 0);
				return;
			}
			if (!current_valid()) {
				state = S_STOP;
				loop_again = 1;
				break;
			}
			next_bn = CURRENT -> sector / 4;
			lba2msf(next_bn, &msf);
			read_count = N_BUFS;
			msf.cdmsf_frame1 = read_count; /* Not BCD! */

			DEBUG((DEBUG_REQUEST, "reading %x:%x.%x %x:%x.%x",
				msf.cdmsf_min0,
				msf.cdmsf_sec0,
				msf.cdmsf_frame0,
				msf.cdmsf_min1,
				msf.cdmsf_sec1,
				msf.cdmsf_frame1));
			DEBUG((DEBUG_REQUEST, "next_bn:%d buf_in:%d"
				" buf_out:%d buf_bn:%d",
				next_bn,
				buf_in,
				buf_out,
				buf_bn[buf_in]));

			exec_read_cmd(COMREAD, &msf);
			state = S_DATA;
			timeout = READ_TIMEOUT;
			break;
		}
		case S_DATA:
			flags = stdt_flags() & (FL_STEN|FL_DTEN);

#if DEBUG_STATE
			if (flags != flags_old) {
				flags_old = flags;
				printk(KERN_DEBUG "optcd: flags:%x\n", flags);
			}
			if (flags == FL_STEN)
				printk(KERN_DEBUG "timeout cnt: %d\n", timeout);
#endif

			switch (flags) {
			case FL_DTEN:		/* only STEN low */
				if (!tries--) {
					printk(KERN_ERR
						"optcd: read block %d failed; "
						"Giving up\n", next_bn);
					if (transfer_is_active) {
						tries = 0;
						break;
					}
					if (current_valid())
						end_request(CURRENT, 0);
					tries = 5;
				}
				state = S_START;
				timeout = READ_TIMEOUT;
				loop_again = 1;
			case (FL_STEN|FL_DTEN):	 /* both high */
				break;
			default:	/* DTEN low */
				tries = 5;
				if (!current_valid() && buf_in == buf_out) {
					state = S_STOP;
					loop_again = 1;
					break;
				}
				if (read_count<=0)
					printk(KERN_WARNING
						"optcd: warning - try to read"
						" 0 frames\n");
				while (read_count) {
					buf_bn[buf_in] = NOBUF;
					if (!flag_low(FL_DTEN, BUSY_TIMEOUT)) {
					/* should be no waiting here!?? */
						printk(KERN_ERR
						   "read_count:%d "
						   "CURRENT->nr_sectors:%ld "
						   "buf_in:%d\n",
							read_count,
							CURRENT->nr_sectors,
							buf_in);
						printk(KERN_ERR
							"transfer active: %x\n",
							transfer_is_active);
						read_count = 0;
						state = S_STOP;
						loop_again = 1;
						end_request(CURRENT, 0);
						break;
					}
					fetch_data(buf+
					    CD_FRAMESIZE*buf_in,
					    CD_FRAMESIZE);
					read_count--;

					DEBUG((DEBUG_REQUEST,
						"S_DATA; ---I've read data- "
						"read_count: %d",
						read_count));
					DEBUG((DEBUG_REQUEST,
						"next_bn:%d  buf_in:%d "
						"buf_out:%d  buf_bn:%d",
						next_bn,
						buf_in,
						buf_out,
						buf_bn[buf_in]));

					buf_bn[buf_in] = next_bn++;
					if (buf_out == NOBUF)
						buf_out = buf_in;
					buf_in = buf_in + 1 ==
						N_BUFS ? 0 : buf_in + 1;
				}
				if (!transfer_is_active) {
					while (current_valid()) {
						transfer();
						if (CURRENT -> nr_sectors == 0)
							end_request(CURRENT, 1);
						else
							break;
					}
				}

				if (current_valid()
				    && (CURRENT -> sector / 4 < next_bn ||
				    CURRENT -> sector / 4 >
				     next_bn + N_BUFS)) {
					state = S_STOP;
					loop_again = 1;
					break;
				}
				timeout = READ_TIMEOUT;
				if (read_count == 0) {
					state = S_STOP;
					loop_again = 1;
					break;
				}
			}
			break;
		case S_STOP:
			if (read_count != 0)
				printk(KERN_ERR
					"optcd: discard data=%x frames\n",
					read_count);
			flush_data();
			if (send_cmd(COMDRVST)) {
				state = S_IDLE;
				while (current_valid())
					end_request(CURRENT, 0);
				return;
			}
			state = S_STOPPING;
			timeout = STOP_TIMEOUT;
			break;
		case S_STOPPING:
			status = fetch_status();
			if (status < 0 && timeout)
					break;
			if ((status >= 0) && (status & ST_DSK_CHG)) {
				toc_uptodate = 0;
				opt_invalidate_buffers();
			}
			if (current_valid()) {
				if (status >= 0) {
					state = S_READ;
					loop_again = 1;
					skip = 1;
					break;
				} else {
					state = S_START;
					timeout = 1;
				}
			} else {
				state = S_IDLE;
				return;
			}
			break;
		default:
			printk(KERN_ERR "optcd: invalid state %d\n", state);
			return;
		} /* case */
	} /* while */

	if (!timeout--) {
		printk(KERN_ERR "optcd: timeout in state %d\n", state);
		state = S_STOP;
		if (exec_cmd(COMSTOP) < 0) {
			state = S_IDLE;
			while (current_valid())
				end_request(CURRENT, 0);
			return;
		}
	}

	mod_timer(&req_timer, jiffies + HZ/100);
}


static void do_optcd_request(request_queue_t * q)
{
	DEBUG((DEBUG_REQUEST, "do_optcd_request(%ld+%ld)",
	       CURRENT -> sector, CURRENT -> nr_sectors));

	if (disk_info.audio) {
		printk(KERN_WARNING "optcd: tried to mount an Audio CD\n");
		end_request(CURRENT, 0);
		return;
	}

	transfer_is_active = 1;
	while (current_valid()) {
		transfer();	/* First try to transfer block from buffers */
		if (CURRENT -> nr_sectors == 0) {
			end_request(CURRENT, 1);
		} else {	/* Want to read a block not in buffer */
			buf_out = NOBUF;
			if (state == S_IDLE) {
				/* %% Should this block the request queue?? */
				if (update_toc() < 0) {
					while (current_valid())
						end_request(CURRENT, 0);
					break;
				}
				/* Start state machine */
				state = S_START;
				timeout = READ_TIMEOUT;
				tries = 5;
				/* %% why not start right away?? */
				mod_timer(&req_timer, jiffies + HZ/100);
			}
			break;
		}
	}
	transfer_is_active = 0;

	DEBUG((DEBUG_REQUEST, "next_bn:%d  buf_in:%d buf_out:%d  buf_bn:%d",
	       next_bn, buf_in, buf_out, buf_bn[buf_in]));
	DEBUG((DEBUG_REQUEST, "do_optcd_request ends"));
}

/* IOCTLs */


static char auto_eject = 0;

static int cdrompause(void)
{
	int status;

	if (audio_status != CDROM_AUDIO_PLAY)
		return -EINVAL;

	status = exec_cmd(COMPAUSEON);
	if (status < 0) {
		DEBUG((DEBUG_VFS, "exec_cmd COMPAUSEON: %02x", -status));
		return -EIO;
	}
	audio_status = CDROM_AUDIO_PAUSED;
	return 0;
}


static int cdromresume(void)
{
	int status;

	if (audio_status != CDROM_AUDIO_PAUSED)
		return -EINVAL;

	status = exec_cmd(COMPAUSEOFF);
	if (status < 0) {
		DEBUG((DEBUG_VFS, "exec_cmd COMPAUSEOFF: %02x", -status));
		audio_status = CDROM_AUDIO_ERROR;
		return -EIO;
	}
	audio_status = CDROM_AUDIO_PLAY;
	return 0;
}


static int cdromplaymsf(void __user *arg)
{
	int status;
	struct cdrom_msf msf;

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

	bin2bcd(&msf);
	status = exec_long_cmd(COMPLAY, &msf);
	if (status < 0) {
		DEBUG((DEBUG_VFS, "exec_long_cmd COMPLAY: %02x", -status));
		audio_status = CDROM_AUDIO_ERROR;
		return -EIO;
	}

	audio_status = CDROM_AUDIO_PLAY;
	return 0;
}


static int cdromplaytrkind(void __user *arg)
{
	int status;
	struct cdrom_ti ti;
	struct cdrom_msf msf;

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

	if (ti.cdti_trk0 < disk_info.first
	    || ti.cdti_trk0 > disk_info.last
	    || ti.cdti_trk1 < ti.cdti_trk0)
		return -EINVAL;
	if (ti.cdti_trk1 > disk_info.last)
		ti.cdti_trk1 = disk_info.last;

	msf.cdmsf_min0 = toc[ti.cdti_trk0].cdsc_absaddr.msf.minute;
	msf.cdmsf_sec0 = toc[ti.cdti_trk0].cdsc_absaddr.msf.second;
	msf.cdmsf_frame0 = toc[ti.cdti_trk0].cdsc_absaddr.msf.frame;
	msf.cdmsf_min1 = toc[ti.cdti_trk1 + 1].cdsc_absaddr.msf.minute;
	msf.cdmsf_sec1 = toc[ti.cdti_trk1 + 1].cdsc_absaddr.msf.second;
	msf.cdmsf_frame1 = toc[ti.cdti_trk1 + 1].cdsc_absaddr.msf.frame;

	DEBUG((DEBUG_VFS, "play %02d:%02d.%02d to %02d:%02d.%02d",
		msf.cdmsf_min0,
		msf.cdmsf_sec0,
		msf.cdmsf_frame0,
		msf.cdmsf_min1,
		msf.cdmsf_sec1,
		msf.cdmsf_frame1));

	bin2bcd(&msf);
	status = exec_long_cmd(COMPLAY, &msf);
	if (status < 0) {
		DEBUG((DEBUG_VFS, "exec_long_cmd COMPLAY: %02x", -status));
		audio_status = CDROM_AUDIO_ERROR;
		return -EIO;
	}

	audio_status = CDROM_AUDIO_PLAY;
	return 0;
}


static int cdromreadtochdr(void __user *arg)
{
	struct cdrom_tochdr tochdr;

	tochdr.cdth_trk0 = disk_info.first;
	tochdr.cdth_trk1 = disk_info.last;

	return copy_to_user(arg, &tochdr, sizeof tochdr) ? -EFAULT : 0;
}


static int cdromreadtocentry(void __user *arg)
{
	struct cdrom_tocentry entry;
	struct cdrom_subchnl *tocptr;

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

	if (entry.cdte_track == CDROM_LEADOUT)
		tocptr = &toc[disk_info.last + 1];
	else if (entry.cdte_track > disk_info.last
		|| entry.cdte_track < disk_info.first)
		return -EINVAL;
	else
		tocptr = &toc[entry.cdte_track];

	entry.cdte_adr = tocptr->cdsc_adr;
	entry.cdte_ctrl = tocptr->cdsc_ctrl;
	entry.cdte_addr.msf.minute = tocptr->cdsc_absaddr.msf.minute;
	entry.cdte_addr.msf.second = tocptr->cdsc_absaddr.msf.second;
	entry.cdte_addr.msf.frame = tocptr->cdsc_absaddr.msf.frame;
	/* %% What should go into entry.cdte_datamode? */

	if (entry.cdte_format == CDROM_LBA)
		msf2lba(&entry.cdte_addr);
	else if (entry.cdte_format != CDROM_MSF)
		return -EINVAL;

	return copy_to_user(arg, &entry, sizeof entry) ? -EFAULT : 0;
}


static int cdromvolctrl(void __user *arg)
{
	int status;
	struct cdrom_volctrl volctrl;
	struct cdrom_msf msf;

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

	msf.cdmsf_min0 = 0x10;
	msf.cdmsf_sec0 = 0x32;
	msf.cdmsf_frame0 = volctrl.channel0;
	msf.cdmsf_min1 = volctrl.channel1;
	msf.cdmsf_sec1 = volctrl.channel2;
	msf.cdmsf_frame1 = volctrl.channel3;

	status = exec_long_cmd(COMCHCTRL, &msf);
	if (status < 0) {
		DEBUG((DEBUG_VFS, "exec_long_cmd COMCHCTRL: %02x", -status));
		return -EIO;
	}
	return 0;
}


static int cdromsubchnl(void __user *arg)
{
	int status;
	struct cdrom_subchnl subchnl;

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

	if (subchnl.cdsc_format != CDROM_LBA
	    && subchnl.cdsc_format != CDROM_MSF)
		return -EINVAL;

	status = get_q_channel(&subchnl);
	if (status < 0) {
		DEBUG((DEBUG_VFS, "get_q_channel: %02x", -status));
		return -EIO;
	}

	if (copy_to_user(arg, &subchnl, sizeof subchnl))
		return -EFAULT;
	return 0;
}


static struct gendisk *optcd_disk;


static int cdromread(void __user *arg, int blocksize, int cmd)
{
	int status;
	struct cdrom_msf msf;

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

	bin2bcd(&msf);
	msf.cdmsf_min1 = 0;
	msf.cdmsf_sec1 = 0;
	msf.cdmsf_frame1 = 1;	/* read only one frame */
	status = exec_read_cmd(cmd, &msf);

	DEBUG((DEBUG_VFS, "read cmd status 0x%x", status));

	if (!sleep_flag_low(FL_DTEN, SLEEP_TIMEOUT))
		return -EIO;

	fetch_data(optcd_disk->private_data, blocksize);

	if (copy_to_user(arg, optcd_disk->private_data, blocksize))
		return -EFAULT;

	return 0;
}


static int cdromseek(void __user *arg)
{
	int status;
	struct cdrom_msf msf;

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

	bin2bcd(&msf);
	status = exec_seek_cmd(COMSEEK, &msf);

	DEBUG((DEBUG_VFS, "COMSEEK status 0x%x", status));

	if (status < 0)
		return -EIO;
	return 0;
}


#ifdef MULTISESSION
static int cdrommultisession(void __user *arg)
{
	struct cdrom_multisession ms;

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

	ms.addr.msf.minute = disk_info.last_session.minute;
	ms.addr.msf.second = disk_info.last_session.second;
	ms.addr.msf.frame = disk_info.last_session.frame;

	if (ms.addr_format != CDROM_LBA
	   && ms.addr_format != CDROM_MSF)
		return -EINVAL;
	if (ms.addr_format == CDROM_LBA)
		msf2lba(&ms.addr);

	ms.xa_flag = disk_info.xa;

  	if (copy_to_user(arg, &ms, sizeof(struct cdrom_multisession)))
		return -EFAULT;

#if DEBUG_MULTIS
 	if (ms.addr_format == CDROM_MSF)
               	printk(KERN_DEBUG
			"optcd: multisession xa:%d, msf:%02d:%02d.%02d\n",
			ms.xa_flag,
			ms.addr.msf.minute,
			ms.addr.msf.second,
			ms.addr.msf.frame);
	else
		printk(KERN_DEBUG
		    "optcd: multisession %d, lba:0x%08x [%02d:%02d.%02d])\n",
			ms.xa_flag,
			ms.addr.lba,
			disk_info.last_session.minute,
			disk_info.last_session.second,
			disk_info.last_session.frame);
#endif /* DEBUG_MULTIS */

	return 0;
}
#endif /* MULTISESSION */


static int cdromreset(void)
{
	if (state != S_IDLE) {
		error = 1;
		tries = 0;
	}

	toc_uptodate = 0;
	disk_changed = 1;
	opt_invalidate_buffers();
	audio_status = CDROM_AUDIO_NO_STATUS;

	if (!reset_drive())
		return -EIO;
	return 0;
}

/* VFS calls */


static int opt_ioctl(struct inode *ip, struct file *fp,
                     unsigned int cmd, unsigned long arg)
{
	int status, err, retval = 0;
	void __user *argp = (void __user *)arg;

	DEBUG((DEBUG_VFS, "starting opt_ioctl"));

	if (!ip)
		return -EINVAL;

	if (cmd == CDROMRESET)
		return cdromreset();

	/* is do_optcd_request or another ioctl busy? */
	if (state != S_IDLE || in_vfs)
		return -EBUSY;

	in_vfs = 1;

	status = drive_status();
	if (status < 0) {
		DEBUG((DEBUG_VFS, "drive_status: %02x", -status));
		in_vfs = 0;
		return -EIO;
	}

	if (status & ST_DOOR_OPEN)
		switch (cmd) {	/* Actions that can be taken with door open */
		case CDROMCLOSETRAY:
			/* We do this before trying to read the toc. */
			err = exec_cmd(COMCLOSE);
			if (err < 0) {
				DEBUG((DEBUG_VFS,
				       "exec_cmd COMCLOSE: %02x", -err));
				in_vfs = 0;
				return -EIO;
			}
			break;
		default:	in_vfs = 0;
				return -EBUSY;
		}

	err = update_toc();
	if (err < 0) {
		DEBUG((DEBUG_VFS, "update_toc: %02x", -err));
		in_vfs = 0;
		return -EIO;
	}

	DEBUG((DEBUG_VFS, "ioctl cmd 0x%x", cmd));

	switch (cmd) {
	case CDROMPAUSE:	retval = cdrompause(); break;
	case CDROMRESUME:	retval = cdromresume(); break;
	case CDROMPLAYMSF:	retval = cdromplaymsf(argp); break;
	case CDROMPLAYTRKIND:	retval = cdromplaytrkind(argp); break;
	case CDROMREADTOCHDR:	retval = cdromreadtochdr(argp); break;
	case CDROMREADTOCENTRY:	retval = cdromreadtocentry(argp); break;

	case CDROMSTOP:		err = exec_cmd(COMSTOP);
				if (err < 0) {
					DEBUG((DEBUG_VFS,
						"exec_cmd COMSTOP: %02x",
						-err));
					retval = -EIO;
				} else
					audio_status = CDROM_AUDIO_NO_STATUS;
				break;
	case CDROMSTART:	break;	/* This is a no-op */
	case CDROMEJECT:	err = exec_cmd(COMUNLOCK);
				if (err < 0) {
					DEBUG((DEBUG_VFS,
						"exec_cmd COMUNLOCK: %02x",
						-err));
					retval = -EIO;
					break;
				}
				err = exec_cmd(COMOPEN);
				if (err < 0) {
					DEBUG((DEBUG_VFS,
						"exec_cmd COMOPEN: %02x",
						-err));
					retval = -EIO;
				}
				break;

	case CDROMVOLCTRL:	retval = cdromvolctrl(argp); break;
	case CDROMSUBCHNL:	retval = cdromsubchnl(argp); break;

	/* The drive detects the mode and automatically delivers the
	   correct 2048 bytes, so we don't need these IOCTLs */
	case CDROMREADMODE2:	retval = -EINVAL; break;
	case CDROMREADMODE1:	retval = -EINVAL; break;

	/* Drive doesn't support reading audio */
	case CDROMREADAUDIO:	retval = -EINVAL; break;

	case CDROMEJECT_SW:	auto_eject = (char) arg;
				break;

#ifdef MULTISESSION
	case CDROMMULTISESSION:	retval = cdrommultisession(argp); break;
#endif

	case CDROM_GET_MCN:	retval = -EINVAL; break; /* not implemented */
	case CDROMVOLREAD:	retval = -EINVAL; break; /* not implemented */

	case CDROMREADRAW:
			/* this drive delivers 2340 bytes in raw mode */
			retval = cdromread(argp, CD_FRAMESIZE_RAW1, COMREADRAW);
			break;
	case CDROMREADCOOKED:
			retval = cdromread(argp, CD_FRAMESIZE, COMREAD);
			break;
	case CDROMREADALL:
			retval = cdromread(argp, CD_FRAMESIZE_RAWER, COMREADALL);
			break;

	case CDROMSEEK:		retval = cdromseek(argp); break;
	case CDROMPLAYBLK:	retval = -EINVAL; break; /* not implemented */
	case CDROMCLOSETRAY:	break;	/* The action was taken earlier */
	default:		retval = -EINVAL;
	}
	in_vfs = 0;
	return retval;
}


static int open_count = 0;

/* Open device special file; check that a disk is in. */
static int opt_open(struct inode *ip, struct file *fp)
{
	DEBUG((DEBUG_VFS, "starting opt_open"));

	if (!open_count && state == S_IDLE) {
		int status;
		char *buf;

		buf = kmalloc(CD_FRAMESIZE_RAWER, GFP_KERNEL);
		if (!buf) {
			printk(KERN_INFO "optcd: cannot allocate read buffer\n");
			return -ENOMEM;
		}
		optcd_disk->private_data = buf;		/* save read buffer */

		toc_uptodate = 0;
		opt_invalidate_buffers();

		status = exec_cmd(COMCLOSE);	/* close door */
		if (status < 0) {
			DEBUG((DEBUG_VFS, "exec_cmd COMCLOSE: %02x", -status));
		}

		status = drive_status();
		if (status < 0) {
			DEBUG((DEBUG_VFS, "drive_status: %02x", -status));
			goto err_out;
		}
		DEBUG((DEBUG_VFS, "status: %02x", status));
		if ((status & ST_DOOR_OPEN) || (status & ST_DRVERR)) {
			printk(KERN_INFO "optcd: no disk or door open\n");
			goto err_out;
		}
		status = exec_cmd(COMLOCK);		/* Lock door */
		if (status < 0) {
			DEBUG((DEBUG_VFS, "exec_cmd COMLOCK: %02x", -status));
		}
		status = update_toc();	/* Read table of contents */
		if (status < 0)	{
			DEBUG((DEBUG_VFS, "update_toc: %02x", -status));
	 		status = exec_cmd(COMUNLOCK);	/* Unlock door */
			if (status < 0) {
				DEBUG((DEBUG_VFS,
				       "exec_cmd COMUNLOCK: %02x", -status));
			}
			goto err_out;
		}
		open_count++;
	}

	DEBUG((DEBUG_VFS, "exiting opt_open"));

	return 0;

err_out:
	return -EIO;
}


/* Release device special file; flush all blocks from the buffer cache */
static int opt_release(struct inode *ip, struct file *fp)
{
	int status;

	DEBUG((DEBUG_VFS, "executing opt_release"));
	DEBUG((DEBUG_VFS, "inode: %p, device: %s, file: %p\n",
		ip, ip->i_bdev->bd_disk->disk_name, fp));

	if (!--open_count) {
		toc_uptodate = 0;
		opt_invalidate_buffers();
	 	status = exec_cmd(COMUNLOCK);	/* Unlock door */
		if (status < 0) {
			DEBUG((DEBUG_VFS, "exec_cmd COMUNLOCK: %02x", -status));
		}
		if (auto_eject) {
			status = exec_cmd(COMOPEN);
			DEBUG((DEBUG_VFS, "exec_cmd COMOPEN: %02x", -status));
		}
		kfree(optcd_disk->private_data);
		del_timer(&delay_timer);
		del_timer(&req_timer);
	}
	return 0;
}


/* Check if disk has been changed */
static int opt_media_change(struct gendisk *disk)
{
	DEBUG((DEBUG_VFS, "executing opt_media_change"));
	DEBUG((DEBUG_VFS, "dev: %s; disk_changed = %d\n",
			disk->disk_name, disk_changed));

	if (disk_changed) {
		disk_changed = 0;
		return 1;
	}
	return 0;
}

/* Driver initialisation */


/* Returns 1 if a drive is detected with a version string
   starting with "DOLPHIN". Otherwise 0. */
static int __init version_ok(void)
{
	char devname[100];
	int count, i, ch, status;

	status = exec_cmd(COMVERSION);
	if (status < 0) {
		DEBUG((DEBUG_VFS, "exec_cmd COMVERSION: %02x", -status));
		return 0;
	}
	if ((count = get_data(1)) < 0) {
		DEBUG((DEBUG_VFS, "get_data(1): %02x", -count));
		return 0;
	}
	for (i = 0, ch = -1; count > 0; count--) {
		if ((ch = get_data(1)) < 0) {
			DEBUG((DEBUG_VFS, "get_data(1): %02x", -ch));
			break;
		}
		if (i < 99)
			devname[i++] = ch;
	}
	devname[i] = '\0';
	if (ch < 0)
		return 0;

	printk(KERN_INFO "optcd: Device %s detected\n", devname);
	return ((devname[0] == 'D')
	     && (devname[1] == 'O')
	     && (devname[2] == 'L')
	     && (devname[3] == 'P')
	     && (devname[4] == 'H')
	     && (devname[5] == 'I')
	     && (devname[6] == 'N'));
}


static struct block_device_operations opt_fops = {
	.owner		= THIS_MODULE,
	.open		= opt_open,
	.release	= opt_release,
	.ioctl		= opt_ioctl,
	.media_changed	= opt_media_change,
};

#ifndef MODULE
/* Get kernel parameter when used as a kernel driver */
static int optcd_setup(char *str)
{
	int ints[4];
	(void)get_options(str, ARRAY_SIZE(ints), ints);
	
	if (ints[0] > 0)
		optcd_port = ints[1];

 	return 1;
}

__setup("optcd=", optcd_setup);

#endif /* MODULE */

/* Test for presence of drive and initialize it. Called at boot time
   or during module initialisation. */
static int __init optcd_init(void)
{
	int status;

	if (optcd_port <= 0) {
		printk(KERN_INFO
			"optcd: no Optics Storage CDROM Initialization\n");
		return -EIO;
	}
	optcd_disk = alloc_disk(1);
	if (!optcd_disk) {
		printk(KERN_ERR "optcd: can't allocate disk\n");
		return -ENOMEM;
	}
	optcd_disk->major = MAJOR_NR;
	optcd_disk->first_minor = 0;
	optcd_disk->fops = &opt_fops;
	sprintf(optcd_disk->disk_name, "optcd");
	sprintf(optcd_disk->devfs_name, "optcd");

	if (!request_region(optcd_port, 4, "optcd")) {
		printk(KERN_ERR "optcd: conflict, I/O port 0x%x already used\n",
			optcd_port);
		put_disk(optcd_disk);
		return -EIO;
	}

	if (!reset_drive()) {
		printk(KERN_ERR "optcd: drive at 0x%x not ready\n", optcd_port);
		release_region(optcd_port, 4);
		put_disk(optcd_disk);
		return -EIO;
	}
	if (!version_ok()) {
		printk(KERN_ERR "optcd: unknown drive detected; aborting\n");
		release_region(optcd_port, 4);
		put_disk(optcd_disk);
		return -EIO;
	}
	status = exec_cmd(COMINITDOUBLE);
	if (status < 0) {
		printk(KERN_ERR "optcd: cannot init double speed mode\n");
		release_region(optcd_port, 4);
		DEBUG((DEBUG_VFS, "exec_cmd COMINITDOUBLE: %02x", -status));
		put_disk(optcd_disk);
		return -EIO;
	}
	if (register_blkdev(MAJOR_NR, "optcd")) {
		release_region(optcd_port, 4);
		put_disk(optcd_disk);
		return -EIO;
	}


	opt_queue = blk_init_queue(do_optcd_request, &optcd_lock);
	if (!opt_queue) {
		unregister_blkdev(MAJOR_NR, "optcd");
		release_region(optcd_port, 4);
		put_disk(optcd_disk);
		return -ENOMEM;
	}

	blk_queue_hardsect_size(opt_queue, 2048);
	optcd_disk->queue = opt_queue;
	add_disk(optcd_disk);

	printk(KERN_INFO "optcd: DOLPHIN 8000 AT CDROM at 0x%x\n", optcd_port);
	return 0;
}


static void __exit optcd_exit(void)
{
	del_gendisk(optcd_disk);
	put_disk(optcd_disk);
	if (unregister_blkdev(MAJOR_NR, "optcd") == -EINVAL) {
		printk(KERN_ERR "optcd: what's that: can't unregister\n");
		return;
	}
	blk_cleanup_queue(opt_queue);
	release_region(optcd_port, 4);
	printk(KERN_INFO "optcd: module released.\n");
}

module_init(optcd_init);
module_exit(optcd_exit);

MODULE_LICENSE("GPL");
MODULE_ALIAS_BLOCKDEV_MAJOR(OPTICS_CDROM_MAJOR);