summaryrefslogtreecommitdiffstats
path: root/firmware/mpeg.c
blob: 0f676f1612a69c038328aed07d69266b460f25c0 (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
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2002 by Linus Nielsen Feltzing
 *
 * All files in this archive are subject to the GNU General Public License.
 * See the file COPYING in the source tree root for full license agreement.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
#include <stdbool.h>
#include "config.h"
#include "debug.h"
#include "panic.h"
#include "id3.h"
#include "mpeg.h"
#include "ata.h"
#include "string.h"
#include <kernel.h>
#include "thread.h"
#include "errno.h"
#include "mp3data.h"
#include "buffer.h"
#include "mp3_playback.h"
#ifndef SIMULATOR
#include "i2c.h"
#include "mas.h"
#include "dac.h"
#include "system.h"
#include "usb.h"
#include "file.h"
#include "hwcompat.h"
#endif /* #ifndef SIMULATOR */

extern void bitswap(unsigned char *data, int length);

#ifdef HAVE_MAS3587F
static void init_recording(void);
static void start_prerecording(void);
static void start_recording(void);
static void stop_recording(void);
static int get_unsaved_space(void);
#endif /* #ifdef HAVE_MAS3587F */

#ifndef SIMULATOR
static int get_unplayed_space(void);
static int get_playable_space(void);
static int get_unswapped_space(void);
#endif /* #ifndef SIMULATOR */

#define MPEG_PLAY         1
#define MPEG_STOP         2
#define MPEG_PAUSE        3
#define MPEG_RESUME       4
#define MPEG_NEXT         5
#define MPEG_PREV         6
#define MPEG_FF_REWIND    7
#define MPEG_FLUSH_RELOAD 8
#define MPEG_RECORD 9
#define MPEG_INIT_RECORDING 10
#define MPEG_INIT_PLAYBACK 11
#define MPEG_NEW_FILE    12
#define MPEG_NEED_DATA    100
#define MPEG_TRACK_CHANGE 101
#define MPEG_SAVE_DATA    102
#define MPEG_STOP_DONE    103

#ifdef HAVE_MAS3587F
extern enum /* from mp3_playback.c */
{
    MPEG_DECODER,
    MPEG_ENCODER
} mpeg_mode;
#endif /* #ifdef HAVE_MAS3587F */

extern char* playlist_peek(int steps);
extern bool playlist_check(int steps);
extern int playlist_next(int steps);
extern int playlist_amount(void);
extern void update_file_pos( int id, int pos );

/* list of tracks in memory */
#define MAX_ID3_TAGS (1<<4) /* Must be power of 2 */
#define MAX_ID3_TAGS_MASK (MAX_ID3_TAGS - 1)

struct id3tag
{
    struct mp3entry id3;
    int mempos;
    bool used;
};

static struct id3tag *id3tags[MAX_ID3_TAGS];
static struct id3tag _id3tags[MAX_ID3_TAGS];

static unsigned int current_track_counter = 0;
static unsigned int last_track_counter = 0;

#ifndef SIMULATOR

static int tag_read_idx = 0;
static int tag_write_idx = 0;

static int num_tracks_in_memory(void)
{
    return (tag_write_idx - tag_read_idx) & MAX_ID3_TAGS_MASK;
}
#endif /* #ifndef SIMULATOR */

#ifndef SIMULATOR
static void debug_tags(void)
{
#ifdef DEBUG_TAGS
    int i;

    for(i = 0;i < MAX_ID3_TAGS;i++)
    {
        DEBUGF("id3tags[%d]: %08x", i, id3tags[i]);
        if(id3tags[i])
            DEBUGF(" - %s", id3tags[i]->id3.path);
        DEBUGF("\n");
    }
    DEBUGF("read: %d, write :%d\n", tag_read_idx, tag_write_idx);
    DEBUGF("num_tracks_in_memory: %d\n", num_tracks_in_memory());
#endif /* #ifdef DEBUG_TAGS */
}

static bool append_tag(struct id3tag *tag)
{
    if(num_tracks_in_memory() < MAX_ID3_TAGS - 1)
    {
        id3tags[tag_write_idx] = tag;
        tag_write_idx = (tag_write_idx+1) & MAX_ID3_TAGS_MASK;
        debug_tags();
        return true;
    }
    else
    {
        DEBUGF("Tag memory is full\n");
        return false;
    }
}

static void remove_current_tag(void)
{
    int oldidx = tag_read_idx;
    
    if(num_tracks_in_memory() > 0)
    {
        /* First move the index, so nobody tries to access the tag */
        tag_read_idx = (tag_read_idx+1) & MAX_ID3_TAGS_MASK;

        /* Now delete it */
        id3tags[oldidx]->used = false;
        id3tags[oldidx] = NULL;
        debug_tags();
    }
}

static void remove_all_non_current_tags(void)
{
    int i = (tag_read_idx+1) & MAX_ID3_TAGS_MASK;

    while (i != tag_write_idx)
    {
        id3tags[i]->used = false;
        id3tags[i] = NULL;

        i = (i+1) & MAX_ID3_TAGS_MASK;
    }

    tag_write_idx = (tag_read_idx+1) & MAX_ID3_TAGS_MASK;
    debug_tags();
}

static void remove_all_tags(void)
{
    int i;
    
    for(i = 0;i < MAX_ID3_TAGS;i++)
        remove_current_tag();

    tag_write_idx = tag_read_idx;

    debug_tags();
}
#endif /* #ifndef SIMULATOR */

static void set_elapsed(struct mp3entry* id3)
{
    if ( id3->vbr ) {
        if ( id3->has_toc ) {
            /* calculate elapsed time using TOC */
            int i;
            unsigned int remainder, plen, relpos, nextpos;

            /* find wich percent we're at */
            for (i=0; i<100; i++ )
            {
                if ( id3->offset < (int)(id3->toc[i] * (id3->filesize / 256)) )
                {
                    break;
                }
            }
            
            i--;
            if (i < 0)
                i = 0;

            relpos = id3->toc[i];

            if (i < 99)
            {
                nextpos = id3->toc[i+1];
            }
            else
            {
                nextpos = 256; 
            }

            remainder = id3->offset - (relpos * (id3->filesize / 256));

            /* set time for this percent (divide before multiply to prevent
               overflow on long files. loss of precision is negligible on
               short files) */
            id3->elapsed = i * (id3->length / 100);

            /* calculate remainder time */
            plen = (nextpos - relpos) * (id3->filesize / 256);
            id3->elapsed += (((remainder * 100) / plen) *
                             (id3->length / 10000));
        }
        else {
            /* no TOC exists. set a rough estimate using average bitrate */
            int tpk = id3->length / (id3->filesize / 1024);
            id3->elapsed = id3->offset / 1024 * tpk;
        }
    }
    else
        /* constant bitrate == simple frame calculation */
        id3->elapsed = id3->offset / id3->bpf * id3->tpf;
}

static bool paused; /* playback is paused */

static unsigned int mpeg_errno;

#ifdef SIMULATOR
static bool is_playing = false;
static bool playing = false;
#else
static int last_dma_tick = 0;

extern unsigned long mas_version_code;

static struct event_queue mpeg_queue;
static char mpeg_stack[DEFAULT_STACK_SIZE + 0x1000];
static char mpeg_thread_name[] = "mpeg";

static int mp3buflen;
static int mp3buf_write;
static int mp3buf_swapwrite;
static int mp3buf_read;

static int last_dma_chunk_size;

static bool playing; /* We are playing an MP3 stream */
static bool play_pending; /* We are about to start playing */
static bool is_playing; /* We are (attempting to) playing MP3 files */
static bool filling; /* We are filling the buffer with data from disk */
static bool dma_underrun; /* True when the DMA has stopped because of
                             slow disk reading (read error, shaking) */
static int low_watermark; /* Dynamic low watermark level */
static int low_watermark_margin; /* Extra time in seconds for watermark */
static int lowest_watermark_level; /* Debug value to observe the buffer
                                      usage */
#ifdef HAVE_MAS3587F
static bool is_recording; /* We are recording */
static bool stop_pending;
unsigned long record_start_time; /* Value of current_tick when recording
                                    was started */
static bool saving; /* We are saving the buffer to disk */
static char recording_filename[MAX_PATH]; /* argument to thread */
static char delayed_filename[MAX_PATH]; /* internal copy of above */
static int rec_frequency_index; /* For create_xing_header() calls */
static int rec_version_index;   /* For create_xing_header() calls */
static bool disable_xing_header; /* When splitting files */

static bool prerecording; /* True if prerecording is enabled */
static bool is_prerecording; /* True if we are prerecording */
static int prerecord_buffer[MPEG_MAX_PRERECORD_SECONDS]; /* Array of buffer
                                                            indexes for each
                                                            prerecorded
                                                            second */
static int prerecord_index; /* Current index in the prerecord buffer */
static int prerecording_max_seconds;   /* Max number of seconds to store */
static int prerecord_count; /* Number of seconds in the prerecord buffer */
static int prerecord_timeout; /* The tick count of the next prerecord data store */
#endif /* #ifdef HAVE_MAS3587F */

static int mpeg_file;

/* Synchronization variables */
#ifdef HAVE_MAS3587F
static bool init_recording_done;
static bool init_playback_done;
#endif /* #ifdef HAVE_MAS3587F */
static bool mpeg_stop_done;

static void recalculate_watermark(int bitrate)
{
    int bytes_per_sec;
    int time = ata_spinup_time;

    /* A bitrate of 0 probably means empty VBR header. We play safe
       and set a high threshold */
    if(bitrate == 0)
        bitrate = 320;
    
    bytes_per_sec = bitrate * 1000 / 8;
    
    if(time)
    {
        /* No drive spins up faster than 3.5s */
        if(time < 350)
            time = 350;

        time = time * 3;
        low_watermark = ((low_watermark_margin * HZ + time) *
                         bytes_per_sec) / HZ;
    }
    else
    {
        low_watermark = MPEG_LOW_WATER;
    }
}

void mpeg_set_buffer_margin(int seconds)
{
    low_watermark_margin = seconds;
}

void mpeg_get_debugdata(struct mpeg_debug *dbgdata)
{
    dbgdata->mp3buflen = mp3buflen;
    dbgdata->mp3buf_write = mp3buf_write;
    dbgdata->mp3buf_swapwrite = mp3buf_swapwrite;
    dbgdata->mp3buf_read = mp3buf_read;

    dbgdata->last_dma_chunk_size = last_dma_chunk_size;

    dbgdata->dma_on = (SCR0 & 0x80) != 0;
    dbgdata->playing = playing;
    dbgdata->play_pending = play_pending;
    dbgdata->is_playing = is_playing;
    dbgdata->filling = filling;
    dbgdata->dma_underrun = dma_underrun;

    dbgdata->unplayed_space = get_unplayed_space();
    dbgdata->playable_space = get_playable_space();
    dbgdata->unswapped_space = get_unswapped_space();

    dbgdata->low_watermark_level = low_watermark;
    dbgdata->lowest_watermark_level = lowest_watermark_level;
}

#ifdef DEBUG
static void dbg_timer_start(void)
{
    /* We are using timer 2 */
    
    TSTR &= ~0x04; /* Stop the timer */
    TSNC &= ~0x04; /* No synchronization */
    TMDR &= ~0x44; /* Operate normally */

    TCNT2 = 0;   /* Start counting at 0 */
    TCR2 = 0x03; /* Sysclock/8 */

    TSTR |= 0x04; /* Start timer 2 */
}

static int dbg_cnt2us(unsigned int cnt)
{
    return (cnt * 10000) / (FREQ/800);
}
#endif /* #ifdef DEBUG */

static int get_unplayed_space(void)
{
    int space = mp3buf_write - mp3buf_read;
    if (space < 0)
        space += mp3buflen;
    return space;
}

static int get_playable_space(void)
{
    int space = mp3buf_swapwrite - mp3buf_read;
    if (space < 0)
        space += mp3buflen;
    return space;
}

static int get_unplayed_space_current_song(void)
{
    int space;

    if (num_tracks_in_memory() > 1)
    {
        int track_offset = (tag_read_idx+1) & MAX_ID3_TAGS_MASK;

        space = id3tags[track_offset]->mempos - mp3buf_read;
    }
    else
    {
        space = mp3buf_write - mp3buf_read;
    }

    if (space < 0)
        space += mp3buflen;

    return space;
}

static int get_unswapped_space(void)
{
    int space = mp3buf_write - mp3buf_swapwrite;
    if (space < 0)
        space += mp3buflen;
    return space;
}

#ifdef HAVE_MAS3587F
static int get_unsaved_space(void)
{
    int space = mp3buf_write - mp3buf_read;
    if (space < 0)
        space += mp3buflen;
    return space;
}
#endif /* #ifdef HAVE_MAS3587F */

#ifdef HAVE_MAS3587F
#ifdef DEBUG
static long timing_info_index = 0;
static long timing_info[1024];
#endif /* #ifdef DEBUG */
static bool inverted_pr;
static unsigned long num_rec_bytes;
static unsigned long num_recorded_frames;

static void drain_dma_buffer(void)
{
    if(inverted_pr)
    {
        while((*((volatile unsigned char *)PBDR_ADDR) & 0x40))
        {
            or_b(0x08, &PADRH);
            
            while(*((volatile unsigned char *)PBDR_ADDR) & 0x80);
                    
            /* It must take at least 5 cycles before
               the data is read */
            asm(" nop\n nop\n nop\n");
            asm(" nop\n nop\n nop\n");
            and_b(~0x08, &PADRH);

            while(!(*((volatile unsigned char *)PBDR_ADDR) & 0x80));
        }
    }
    else
    {
        while((*((volatile unsigned char *)PBDR_ADDR) & 0x40))
        {
            and_b(~0x08, &PADRH);
            
            while(*((volatile unsigned char *)PBDR_ADDR) & 0x80);
            
            /* It must take at least 5 cycles before
               the data is read */
            asm(" nop\n nop\n nop\n");
            asm(" nop\n nop\n nop\n");
                    
            or_b(0x08, &PADRH);

            while(!(*((volatile unsigned char *)PBDR_ADDR) & 0x80));
        }
    }
}

#endif /* #ifdef HAVE_MAS3587F */

void rec_tick (void) __attribute__ ((section (".icode")));
void rec_tick(void)
{
#ifdef HAVE_MAS3587F
    int i;
    int num_bytes;
    if(is_recording && (PBDR & 0x4000))
    {
#ifdef DEBUG
        timing_info[timing_info_index++] = current_tick;
        TCNT2 = 0;
#endif /* #ifdef DEBUG */
        /* We read as long as EOD is high, but max 30 bytes.
           This code is optimized, and should probably be
           written in assembler instead. */
        if(inverted_pr)
        {
            i = 0;
            while((*((volatile unsigned char *)PBDR_ADDR) & 0x40)
                  && i < 30)
            {
                or_b(0x08, &PADRH);

                while(*((volatile unsigned char *)PBDR_ADDR) & 0x80);
                
                /* It must take at least 5 cycles before
                   the data is read */
                asm(" nop\n nop\n nop\n");
                mp3buf[mp3buf_write++] = *(unsigned char *)0x4000000;
                
                if(mp3buf_write >= mp3buflen)
                    mp3buf_write = 0;

                i++;
                
                and_b(~0x08, &PADRH);

                /* No wait for /RTW, cause it's not necessary */
            }
        }
        else /* !inverted_pr */
        {
            i = 0;
            while((*((volatile unsigned char *)PBDR_ADDR) & 0x40)
                  && i < 30)
            {
                and_b(~0x08, &PADRH);
                
                while(*((volatile unsigned char *)PBDR_ADDR) & 0x80);
                
                /* It must take at least 5 cycles before
                   the data is read */
                asm(" nop\n nop\n nop\n");
                mp3buf[mp3buf_write++] = *(unsigned char *)0x4000000;
                
                if(mp3buf_write >= mp3buflen)
                    mp3buf_write = 0;

                i++;
                
                or_b(0x08, &PADRH);

                /* No wait for /RTW, cause it's not necessary */
            }
        }
#ifdef DEBUG
        timing_info[timing_info_index++] = TCNT2 + (i << 16);
        timing_info_index &= 0x3ff;
#endif /* #ifdef DEBUG */

        num_rec_bytes += i;
        
        if(is_prerecording)
        {
            if(TIME_AFTER(current_tick, prerecord_timeout))
            {
                prerecord_timeout = current_tick + HZ;

                /* Store the write pointer every second */
                prerecord_buffer[prerecord_index++] = mp3buf_write;

                /* Wrap if necessary */
                if(prerecord_index == prerecording_max_seconds)
                    prerecord_index = 0;

                /* Update the number of seconds recorded */
                if(prerecord_count < prerecording_max_seconds)
                    prerecord_count++;
            }
        }
        else
        {
            /* Signal to save the data if we are running out of buffer
               space */
            num_bytes = mp3buf_write - mp3buf_read;
            if(num_bytes < 0)
                num_bytes += mp3buflen;
            
            if(mp3buflen - num_bytes < MPEG_RECORDING_LOW_WATER && !saving)
            {
                saving = true;
                queue_post(&mpeg_queue, MPEG_SAVE_DATA, 0);
                wake_up_thread();
            }
        }
    }
#endif /* #ifdef HAVE_MAS3587F */
}

void playback_tick(void)
{
    id3tags[tag_read_idx]->id3.elapsed +=
        (current_tick - last_dma_tick) * 1000 / HZ;
    last_dma_tick = current_tick;
}

static void reset_mp3_buffer(void)
{
    mp3buf_read = 0;
    mp3buf_write = 0;
    mp3buf_swapwrite = 0;
    lowest_watermark_level = mp3buflen;
}

 /* DMA transfer end interrupt callback */
static void transfer_end(unsigned char** ppbuf, int* psize)
{
    if(playing && !paused)
    {
        int unplayed_space_left;
        int space_until_end_of_buffer;
        int track_offset = (tag_read_idx+1) & MAX_ID3_TAGS_MASK;

        mp3buf_read += last_dma_chunk_size;
        if(mp3buf_read >= mp3buflen)
            mp3buf_read = 0;
    
        /* First, check if we are on a track boundary */
        if (num_tracks_in_memory() > 0)
        {
            if (mp3buf_read == id3tags[track_offset]->mempos)
            {
                queue_post(&mpeg_queue, MPEG_TRACK_CHANGE, 0);
                track_offset = (track_offset+1) & MAX_ID3_TAGS_MASK;
            }
        }
        
        unplayed_space_left = get_unplayed_space();
        
        space_until_end_of_buffer = mp3buflen - mp3buf_read;
        
        if(!filling && unplayed_space_left < low_watermark)
        {
            filling = true;
            queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
        }
        
        if(unplayed_space_left)
        {
            last_dma_chunk_size = MIN(0x2000, unplayed_space_left);
            last_dma_chunk_size = MIN(last_dma_chunk_size,
                                      space_until_end_of_buffer);

            /* several tracks loaded? */
            if (num_tracks_in_memory() > 1)
            {
                /* will we move across the track boundary? */
                if (( mp3buf_read < id3tags[track_offset]->mempos ) &&
                    ((mp3buf_read+last_dma_chunk_size) >
                     id3tags[track_offset]->mempos ))
                {
                    /* Make sure that we end exactly on the boundary */
                    last_dma_chunk_size = id3tags[track_offset]->mempos
                        - mp3buf_read;
                }
            }

            *psize = last_dma_chunk_size & 0xffff;
            *ppbuf = mp3buf + mp3buf_read;
            id3tags[tag_read_idx]->id3.offset += last_dma_chunk_size;

            /* Update the watermark debug level */
            if(unplayed_space_left < lowest_watermark_level)
                lowest_watermark_level = unplayed_space_left;
        }
        else
        {
            /* Check if the end of data is because of a hard disk error.
               If there is an open file handle, we are still playing music.
               If not, the last file has been loaded, and the file handle is
               closed. */
            if(mpeg_file >= 0)
            {
                /* Update the watermark debug level */
                if(unplayed_space_left < lowest_watermark_level)
                    lowest_watermark_level = unplayed_space_left;
                
                DEBUGF("DMA underrun.\n");
                dma_underrun = true;
            }
            else
            {
                DEBUGF("No more MP3 data. Stopping.\n");

                queue_post(&mpeg_queue, MPEG_TRACK_CHANGE, 0);
                playing = false;
                is_playing = false;
            }
            *psize = 0; /* no more transfer */
        }
    }

    wake_up_thread();
}

static int add_track_to_tag_list(char *filename)
{
    struct id3tag *t = NULL;
    int i;

    /* find a free tag */
    for (i=0; i < MAX_ID3_TAGS_MASK; i++ )
        if ( !_id3tags[i].used )
            t = &_id3tags[i];
    if(t)
    {
        /* grab id3 tag of new file and
           remember where in memory it starts */
        if(mp3info(&(t->id3), filename))
        {
            DEBUGF("Bad mp3\n");
            return -1;
        }
        t->mempos = mp3buf_write;
        t->id3.elapsed = 0;
        if(!append_tag(t))
        {
            DEBUGF("Tag list is full\n");
        }
        else
            t->used = true;
    }
    else
    {
        DEBUGF("No memory available for id3 tag");
    }
    return 0;
}

/* If next_track is true, opens the next track, if false, opens prev track */
static int new_file(int steps)
{
    int max_steps = playlist_amount();
    int start = num_tracks_in_memory() - 1;

    if (start < 0)
        start = 0;

    do {
        char *trackname;

        trackname = playlist_peek( start + steps );
        if ( !trackname )
            return -1;
        
        DEBUGF("playing %s\n", trackname);
        
        mpeg_file = open(trackname, O_RDONLY);
        if(mpeg_file < 0) {
            DEBUGF("Couldn't open file: %s\n",trackname);
            steps++;

            /* Bail out if no file could be opened */
            if(steps > max_steps)
                return -1;
        }
        else
        {
            int new_tag_idx = tag_write_idx;

            if(add_track_to_tag_list(trackname))
            {
                /* Bad mp3 file */
                steps++;
                close(mpeg_file);
                mpeg_file = -1;
            }
            else
            {
                /* skip past id3v2 tag */
                lseek(mpeg_file, 
                      id3tags[new_tag_idx]->id3.first_frame_offset,
                      SEEK_SET);
                id3tags[new_tag_idx]->id3.index = steps;
                id3tags[new_tag_idx]->id3.offset = 0;

                if(id3tags[new_tag_idx]->id3.vbr)
                    /* Average bitrate * 1.5 */
                    recalculate_watermark(
                        (id3tags[new_tag_idx]->id3.bitrate * 3) / 2);
                else
                    recalculate_watermark(
                        id3tags[new_tag_idx]->id3.bitrate);
                    
            }
        }
    } while ( mpeg_file < 0 );

    return 0;
}

static void stop_playing(void)
{
    /* Stop the current stream */
    mp3_play_stop();
    playing = false;
    filling = false;
    if(mpeg_file >= 0)
        close(mpeg_file);
    mpeg_file = -1;
    remove_all_tags();
}

static void update_playlist(void)
{
    int index;

    if (num_tracks_in_memory() > 0)
    {
        index = playlist_next(id3tags[tag_read_idx]->id3.index);
        id3tags[tag_read_idx]->id3.index = index;
    }
}

static void track_change(void)
{
    DEBUGF("Track change\n");

#ifdef HAVE_MAS3587F
    /* Reset the AVC */
    mpeg_sound_set(SOUND_AVC, -1);
#endif /* #ifdef HAVE_MAS3587F */
    remove_current_tag();

    update_playlist();
    current_track_counter++;
}

#ifdef DEBUG
void hexdump(unsigned char *buf, int len)
{
    int i;

    for(i = 0;i < len;i++)
    {
        if(i && (i & 15) == 0)
        {
            DEBUGF("\n");
        }
        DEBUGF("%02x ", buf[i]);
    }
    DEBUGF("\n");
}
#endif /* #ifdef DEBUG */

static void start_playback_if_ready(void)
{
    int playable_space;

    playable_space = mp3buf_swapwrite - mp3buf_read;
    if(playable_space < 0)
        playable_space += mp3buflen;
    
    /* See if we have started playing yet. If not, do it. */
    if(play_pending || dma_underrun)
    {
        /* If the filling has stopped, and we still haven't reached
           the watermark, the file must be smaller than the
           watermark. We must still play it. */
        if((playable_space >= MPEG_PLAY_PENDING_THRESHOLD) ||
           !filling || dma_underrun)
        {
            DEBUGF("P\n");
            play_pending = false;
            playing = true;
			
            if (!paused)
            {
                last_dma_chunk_size = MIN(0x2000, get_unplayed_space_current_song());
                mp3_play_data(mp3buf + mp3buf_read, last_dma_chunk_size, transfer_end);
                dma_underrun = false;

                last_dma_tick = current_tick;
                mp3_play_pause(true);
            }

            /* Tell ourselves that we need more data */
            queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
        }
    }
}

static bool swap_one_chunk(void)
{
    int free_space_left;
    int amount_to_swap;

    free_space_left = get_unswapped_space();

    if(free_space_left == 0 && !play_pending)
        return false;

    /* Swap in larger chunks when the user is waiting for the playback
       to start, or when there is dangerously little playable data left */
    if(play_pending)
        amount_to_swap = MIN(MPEG_PLAY_PENDING_SWAPSIZE, free_space_left);
    else
    {
        if(get_playable_space() < low_watermark)
            amount_to_swap = MIN(MPEG_LOW_WATER_SWAP_CHUNKSIZE,
                                 free_space_left);
        else
            amount_to_swap = MIN(MPEG_SWAP_CHUNKSIZE, free_space_left);
    }
    
    if(mp3buf_write < mp3buf_swapwrite)
        amount_to_swap = MIN(mp3buflen - mp3buf_swapwrite,
                             amount_to_swap);
    else
        amount_to_swap = MIN(mp3buf_write - mp3buf_swapwrite,
                             amount_to_swap);

    bitswap(mp3buf + mp3buf_swapwrite, amount_to_swap);

    mp3buf_swapwrite += amount_to_swap;
    if(mp3buf_swapwrite >= mp3buflen)
    {
        mp3buf_swapwrite = 0;
    }

    return true;
}

static const unsigned char empty_id3_header[] =
{
    'I', 'D', '3', 0x04, 0x00, 0x00,
    0x00, 0x00, 0x1f, 0x76 /* Size is 4096 minus 10 bytes for the header */
};

#ifdef HAVE_MAS3587F
static unsigned long get_last_recorded_header(void)
{
    unsigned long tmp[2];

    /* Read the frame data from the MAS and reconstruct it with the
       frame sync and all */
    mas_readmem(MAS_BANK_D0, 0xfd1, tmp, 2);
    return 0xffe00000 | ((tmp[0] & 0x7c00) << 6) | (tmp[1] & 0xffff);
}
#endif /* #ifdef HAVE_MAS3587F */

static void mpeg_thread(void)
{
    static int pause_tick = 0;
    static unsigned int pause_track = 0;
    struct event ev;
    int len;
    int free_space_left;
    int unplayed_space_left;
    int amount_to_read;
    int t1, t2;
    int start_offset;
#ifdef HAVE_MAS3587F
    int amount_to_save;
    int writelen;
    int framelen;
    unsigned long saved_header = 0;
    int startpos;
    int rc;
    int offset;
    int countdown;
#endif /* #ifdef HAVE_MAS3587F */
    
    is_playing = false;
    play_pending = false;
    playing = false;
    mpeg_file = -1;

    while(1)
    {
#ifdef HAVE_MAS3587F
        if(mpeg_mode == MPEG_DECODER)
        {
#endif /* #ifdef HAVE_MAS3587F */
        yield();

        /* Swap if necessary, and don't block on the queue_wait() */
        if(swap_one_chunk())
        {
            queue_wait_w_tmo(&mpeg_queue, &ev, 0);
        }
        else
        {
            DEBUGF("S R:%x W:%x SW:%x\n",
                   mp3buf_read, mp3buf_write, mp3buf_swapwrite);
            queue_wait(&mpeg_queue, &ev);
        }

        start_playback_if_ready();
        
        switch(ev.id)
        {
            case MPEG_PLAY:
                DEBUGF("MPEG_PLAY\n");

#ifdef HAVE_FMRADIO
                /* Silence the A/D input, it may be on because the radio
                   may be playing */
                mas_codec_writereg(6, 0x0000);
#endif /* #ifdef HAVE_FMRADIO */

                /* Stop the current stream */
                play_pending = false;
                playing = false;
                paused = false;
                mp3_play_pause(false);

                reset_mp3_buffer();
                remove_all_tags();

                if(mpeg_file >= 0)
                    close(mpeg_file);

                if ( new_file(0) == -1 )
                {
                    is_playing = false;
                    track_change();
                    break;
                }

                start_offset = (int)ev.data;

                /* mid-song resume? */
                if (start_offset) {
                    struct mp3entry* id3 = &id3tags[tag_read_idx]->id3;
                    lseek(mpeg_file, start_offset, SEEK_SET);
                    id3->offset = start_offset;
                    set_elapsed(id3);
                }
                else {
                    /* skip past id3v2 tag */
                    lseek(mpeg_file, 
                          id3tags[tag_read_idx]->id3.first_frame_offset, 
                          SEEK_SET);

                }

                /* Make it read more data */
                filling = true;
                queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);

                /* Tell the file loading code that we want to start playing
                   as soon as we have some data */
                play_pending = true;

                update_playlist();
                current_track_counter++;
                break;

            case MPEG_STOP:
                DEBUGF("MPEG_STOP\n");
                is_playing = false;
                paused = false;
                stop_playing();
                mpeg_stop_done = true;
                break;

            case MPEG_PAUSE:
                DEBUGF("MPEG_PAUSE\n");
                /* Stop the current stream */
                paused = true;
                playing = false;
                pause_tick = current_tick;
                pause_track = current_track_counter;
                mp3_play_pause(false);
                break;

            case MPEG_RESUME:
                DEBUGF("MPEG_RESUME\n");
                /* Continue the current stream */
                paused = false;
                if (!play_pending)
                {
                    playing = true;
                    if ( current_track_counter == pause_track )
                        last_dma_tick += current_tick - pause_tick;
                    else
                        last_dma_tick = current_tick;                        
                    pause_tick = 0;
                    mp3_play_pause(true);
                }
                break;

            case MPEG_NEXT:
                DEBUGF("MPEG_NEXT\n");
                /* is next track in ram? */
                if ( num_tracks_in_memory() > 1 ) {
                    int unplayed_space_left, unswapped_space_left;

                    /* stop the current stream */
                    play_pending = false;
                    playing = false;
                    mp3_play_pause(false);

                    track_change();
                    mp3buf_read = id3tags[tag_read_idx]->mempos;
                    last_dma_chunk_size = MIN(0x2000, get_unplayed_space_current_song());
                    mp3_play_data(mp3buf + mp3buf_read, last_dma_chunk_size, transfer_end);
                    dma_underrun = false;
                    last_dma_tick = current_tick;

                    unplayed_space_left  = get_unplayed_space();
                    unswapped_space_left = get_unswapped_space();

                    /* should we start reading more data? */
                    if(!filling && (unplayed_space_left < low_watermark)) {
                        filling = true;
                        queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
                        play_pending = true;
                    } else if(unswapped_space_left &&
                              unswapped_space_left > unplayed_space_left) {
                        /* Stop swapping the data from the previous file */
                        mp3buf_swapwrite = mp3buf_read;
                        play_pending = true;
                    } else {
                        playing = true;
                        if (!paused)
                            mp3_play_pause(true);
                    }
                }
                else {
                    if (!playlist_check(1))
                        break;

                    /* stop the current stream */
                    play_pending = false;
                    playing = false;
                    mp3_play_pause(false);

                    reset_mp3_buffer();
                    remove_all_tags();

                    /* Open the next file */
                    if (mpeg_file >= 0)
                        close(mpeg_file);
                    
                    if (new_file(1) < 0) {
                        DEBUGF("No more files to play\n");
                        filling = false;
                    } else {
                        /* Make it read more data */
                        filling = true;
                        queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
                        
                        /* Tell the file loading code that we want
                           to start playing as soon as we have some data */
                        play_pending = true;

                        update_playlist();
                        current_track_counter++;
                    }
                }
                break;

            case MPEG_PREV: {
                DEBUGF("MPEG_PREV\n");

                if (!playlist_check(-1))
                    break;
                
                /* stop the current stream */
                play_pending = false;
                playing = false;
                mp3_play_pause(false);

                reset_mp3_buffer();
                remove_all_tags();

                /* Open the next file */
                if (mpeg_file >= 0)
                    close(mpeg_file);

                if (new_file(-1) < 0) {
                    DEBUGF("No more files to play\n");
                    filling = false;
                } else {
                    /* Make it read more data */
                    filling = true;
                    queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);

                    /* Tell the file loading code that we want to
                       start playing as soon as we have some data */
                    play_pending = true;

                    update_playlist();
                    current_track_counter++;
                }
                break;
            }

            case MPEG_FF_REWIND: {
                struct mp3entry *id3  = mpeg_current_track();
                unsigned int oldtime  = id3->elapsed;
                unsigned int newtime  = (unsigned int)ev.data;
                int curpos, newpos, diffpos;
                DEBUGF("MPEG_FF_REWIND\n");

                id3->elapsed = newtime;

                if (id3->vbr)
                {
                    if (id3->has_toc)
                    {
                        /* Use the TOC to find the new position */
                        unsigned int percent, remainder;
                        int curtoc, nexttoc, plen;
                        
                        percent = (newtime*100)/id3->length; 
                        if (percent > 99)
                            percent = 99;
                        
                        curtoc = id3->toc[percent];
                        
                        if (percent < 99)
                            nexttoc = id3->toc[percent+1];
                        else
                            nexttoc = 256;
                        
                        newpos = (id3->filesize/256)*curtoc;
                        
                        /* Use the remainder to get a more accurate position */
                        remainder   = (newtime*100)%id3->length;
                        remainder   = (remainder*100)/id3->length;
                        plen        = (nexttoc - curtoc)*(id3->filesize/256);
                        newpos     += (plen/100)*remainder;
                    }
                    else
                    {
                        /* No TOC exists, estimate the new position */
                        newpos = (id3->filesize / (id3->length / 1000)) *
                            (newtime / 1000);
                    }
                }
                else if (id3->bpf && id3->tpf)
                    newpos = (newtime/id3->tpf)*id3->bpf;
                else
                {
                    /* Not enough information to FF/Rewind */
                    id3->elapsed = oldtime;
                    break;
                }

                if (newpos >= (int)(id3->filesize - id3->id3v1len))
                {
                    /* Don't seek right to the end of the file so that we can
                       transition properly to the next song */
                    newpos = id3->filesize - id3->id3v1len - 1;
                }
                else if (newpos < (int)id3->first_frame_offset)
                {
                    /* skip past id3v2 tag and other leading garbage */
                    newpos = id3->first_frame_offset;
                }

                if (mpeg_file >= 0)
                    curpos = lseek(mpeg_file, 0, SEEK_CUR);
                else
                    curpos = id3->filesize;

                if (num_tracks_in_memory() > 1)
                {
                    /* We have started loading other tracks that need to be
                       accounted for */
                    int i = tag_read_idx;
                    int j = tag_write_idx - 1;

                    if (j < 0)
                        j = MAX_ID3_TAGS - 1;

                    while (i != j)
                    {
                        curpos += id3tags[i]->id3.filesize;
                        i = (i+1) & MAX_ID3_TAGS_MASK;
                    }
                }

                diffpos = curpos - newpos;

                if(!filling && diffpos >= 0 && diffpos < mp3buflen)
                {
                    int unplayed_space_left, unswapped_space_left;

                    /* We are changing to a position that's already in
                       memory, so we just move the DMA read pointer. */
                    mp3buf_read = mp3buf_write - diffpos;
                    if (mp3buf_read < 0)
                    {
                        mp3buf_read += mp3buflen;
                    }

                    unplayed_space_left  = get_unplayed_space();
                    unswapped_space_left = get_unswapped_space();

                    /* If unswapped_space_left is larger than
                       unplayed_space_left, it means that the swapwrite pointer
                       hasn't yet advanced up to the new location of the read
                       pointer. We just move it, there is no need to swap
                       data that won't be played anyway. */
                    
                    if (unswapped_space_left > unplayed_space_left)
                    {
                        DEBUGF("Moved swapwrite\n");
                        mp3buf_swapwrite = mp3buf_read;
                        play_pending = true;
                    }

                    if (mpeg_file>=0 && unplayed_space_left < low_watermark)
                    {
                        /* We need to load more data before starting */
                        filling = true;
                        queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
                        play_pending = true;
                    }
                    else
                    {
                        /* resume will start at new position */
                        last_dma_chunk_size = 
                            MIN(0x2000, get_unplayed_space_current_song());
                        mp3_play_data(mp3buf + mp3buf_read, 
                            last_dma_chunk_size, transfer_end);
                        dma_underrun = false;
                    }
                }
                else
                {
                    /* Move to the new position in the file and start
                       loading data */
                    reset_mp3_buffer();

                    if (num_tracks_in_memory() > 1)
                    {
                        /* We have to reload the current track */
                        close(mpeg_file);
                        remove_all_non_current_tags();
                        mpeg_file = -1;
                    }

                    if (mpeg_file < 0)
                    {
                        mpeg_file = open(id3->path, O_RDONLY);
                        if (mpeg_file < 0)
                        {
                            id3->elapsed = oldtime;
                            break;
                        }
                    }

                    if(-1 == lseek(mpeg_file, newpos, SEEK_SET))
                    {
                        id3->elapsed = oldtime;
                        break;
                    }

                    filling = true;
                    queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);

                    /* Tell the file loading code that we want to start playing
                       as soon as we have some data */
                    play_pending = true;
                }

                id3->offset = newpos;

                break;
            }

            case MPEG_FLUSH_RELOAD: {
                int  numtracks    = num_tracks_in_memory();
                bool reload_track = false;

                if (numtracks > 1)
                {
                    /* Reload songs */
                    int next = (tag_read_idx+1) & MAX_ID3_TAGS_MASK;

                    /* Reset the buffer */
                    mp3buf_write = id3tags[next]->mempos;

                    /* Reset swapwrite unless we're still swapping current
                       track */
                    if (get_unplayed_space() <= get_playable_space())
                        mp3buf_swapwrite = mp3buf_write;

                    close(mpeg_file);
                    remove_all_non_current_tags();
                    mpeg_file = -1;
                    reload_track = true;
                }
                else if (numtracks == 1 && mpeg_file < 0)
                {
                    reload_track = true;
                }

                if(reload_track && new_file(1) >= 0)
                {
                    /* Tell ourselves that we want more data */
                    queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
                    filling = true;
                }

                break;
            }

            case MPEG_NEED_DATA:
                free_space_left = mp3buf_read - mp3buf_write;

                /* We interpret 0 as "empty buffer" */
                if(free_space_left <= 0)
                    free_space_left = mp3buflen + free_space_left;

                unplayed_space_left = mp3buflen - free_space_left;

                /* Make sure that we don't fill the entire buffer */
                free_space_left -= MPEG_HIGH_WATER;

                /* do we have any more buffer space to fill? */
                if(free_space_left <= MPEG_HIGH_WATER)
                {
                    DEBUGF("0\n");
                    filling = false;
                    ata_sleep();
                    break;
                }

                /* Read small chunks while we are below the low water mark */
                if(unplayed_space_left < low_watermark)
                    amount_to_read = MIN(MPEG_LOW_WATER_CHUNKSIZE,
                                         free_space_left);
                else
                    amount_to_read = free_space_left;

                /* Don't read more than until the end of the buffer */
                amount_to_read = MIN(mp3buflen - mp3buf_write, amount_to_read);
#if MEM == 8    
                amount_to_read = MIN(0x100000, amount_to_read);
#endif /* #if MEM == 8 */

                /* Read as much mpeg data as we can fit in the buffer */
                if(mpeg_file >= 0)
                {
                    DEBUGF("R\n");
                    t1 = current_tick;
                    len = read(mpeg_file, mp3buf+mp3buf_write, amount_to_read);
                    if(len > 0)
                    {
                        t2 = current_tick;
                        DEBUGF("time: %d\n", t2 - t1);
                        DEBUGF("R: %x\n", len);

                        /* Now make sure that we don't feed the MAS with ID3V1
                           data */
                        if (len < amount_to_read)
                        {
                            int tagptr = mp3buf_write + len - 128;
                            int i;
                            char *tag = "TAG";
                            int taglen = 128;
                            
                            for(i = 0;i < 3;i++)
                            {
                                if(tagptr >= mp3buflen)
                                    tagptr -= mp3buflen;

                                if(mp3buf[tagptr] != tag[i])
                                    taglen = 0;

                                tagptr++;
                            }

                            if(taglen)
                            {
                                /* Skip id3v1 tag */
                                DEBUGF("Skipping ID3v1 tag\n");
                                len -= taglen;

                                /* The very rare case when the entire tag
                                   wasn't read in this read() call must be
                                   taken care of */
                                if(len < 0)
                                    len = 0;
                            }
                        }

                        mp3buf_write += len;
                        
                        if(mp3buf_write >= mp3buflen)
                        {
                            mp3buf_write = 0;
                            DEBUGF("W\n");
                        }

                        /* Tell ourselves that we want more data */
                        queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
                    }
                    else
                    {
                        if(len < 0)
                        {
                            DEBUGF("MPEG read error\n");
                        }
                        
                        close(mpeg_file);
                        mpeg_file = -1;
                    
                        if(new_file(1) < 0)
                        {
                            /* No more data to play */
                            DEBUGF("No more files to play\n");
                            filling = false;
                        }
                        else
                        {
                            /* Tell ourselves that we want more data */
                            queue_post(&mpeg_queue, MPEG_NEED_DATA, 0);
                        }
                    }
                }
                break;
                
            case MPEG_TRACK_CHANGE:
                track_change();
                break;

#ifndef USB_NONE
            case SYS_USB_CONNECTED:
                is_playing = false;
                paused = false;
                stop_playing();
#ifndef SIMULATOR
                
                /* Tell the USB thread that we are safe */
                DEBUGF("mpeg_thread got SYS_USB_CONNECTED\n");
                usb_acknowledge(SYS_USB_CONNECTED_ACK);

                /* Wait until the USB cable is extracted again */
                usb_wait_for_disconnect(&mpeg_queue);
#endif /* #ifndef SIMULATOR */
                break;
#endif /* #ifndef USB_NONE */
                
#ifdef HAVE_MAS3587F
            case MPEG_INIT_RECORDING:
                init_recording();
                init_recording_done = true;
                break;
#endif /* #ifdef HAVE_MAS3587F */
            }
#ifdef HAVE_MAS3587F
        }
        else
        {
            queue_wait(&mpeg_queue, &ev);
            switch(ev.id)
            {
                case MPEG_RECORD:
                    if(is_prerecording)
                    {
                        int startpos, i;
                        
                        /* Go back prerecord_count seconds in the buffer */
                        startpos = prerecord_index - prerecord_count;
                        if(startpos < 0)
                            startpos += prerecording_max_seconds;

                        /* Read the mp3 buffer pointer from the prerecord buffer */
                        startpos = prerecord_buffer[startpos];

                        DEBUGF("Start looking at address %x (%x)\n",
                               mp3buf+startpos, startpos);

                        saved_header = get_last_recorded_header();
                        
                        mem_find_next_frame(startpos, &offset, 5000,
                                            saved_header);

                        mp3buf_read = startpos + offset;
                        
                        DEBUGF("New mp3buf_read address: %x (%x)\n",
                               mp3buf+mp3buf_read, mp3buf_read);

                        /* Make room for headers */
                        mp3buf_read -= MPEG_RESERVED_HEADER_SPACE;
                        if(mp3buf_read < 0)
                        {
                            /* Clear the bottom half */
                            memset(mp3buf, 0,
                                   mp3buf_read + MPEG_RESERVED_HEADER_SPACE);

                            /* And the top half */
                            mp3buf_read += mp3buflen;
                            memset(mp3buf + mp3buf_read, 0,
                                   mp3buflen - mp3buf_read);
                        }
                        else
                        {
                            memset(mp3buf + mp3buf_read, 0,
                                   MPEG_RESERVED_HEADER_SPACE);
                        }

                        /* Copy the empty ID3 header */
                        startpos = mp3buf_read;
                        for(i = 0;i < (int)sizeof(empty_id3_header);i++)
                        {
                            mp3buf[startpos++] = empty_id3_header[i];
                            if(startpos == mp3buflen)
                                startpos = 0;
                        }
                        
                        DEBUGF("New mp3buf_read address (reservation): %x\n",
                               mp3buf+mp3buf_read);
                        
                        DEBUGF("Prerecording...\n");
                    }
                    else
                    {
                        reset_mp3_buffer();

                        num_rec_bytes = 0;
                        
                        /* Advance the write pointer to make
                           room for an ID3 tag plus a VBR header */
                        mp3buf_write = MPEG_RESERVED_HEADER_SPACE;
                        memset(mp3buf, 0, MPEG_RESERVED_HEADER_SPACE);
                        
                        /* Insert the ID3 header */
                        memcpy(mp3buf, empty_id3_header,
                               sizeof(empty_id3_header));

                        DEBUGF("Recording...\n");
                    }

                    start_recording();
                    
                    /* delayed until buffer is saved, don't open yet */
                    strcpy(delayed_filename, recording_filename);
                    mpeg_file = -1; 

                    break;

                case MPEG_STOP:
                    DEBUGF("MPEG_STOP\n");

                    /* Store the last recorded header for later use by the
                       Xing header generation */
                    saved_header = get_last_recorded_header();
                    
                    stop_recording();

                    /* Save the remaining data in the buffer */
                    stop_pending = true;
                    queue_post(&mpeg_queue, MPEG_SAVE_DATA, 0);
                    break;
                    
                case MPEG_STOP_DONE:
                    DEBUGF("MPEG_STOP_DONE\n");
                    
                    if(mpeg_file >= 0)
                        close(mpeg_file);

                    if(!disable_xing_header)
                    {
                        /* Create the Xing header */
                        mpeg_file = open(recording_filename, O_RDWR);
                        if(mpeg_file < 0)
                            panicf("rec upd: %d (%s)", mpeg_file,
                                   recording_filename);

                        /* If the number of recorded frames have
                           reached 0x7ffff, we can no longer trust it */
                        if(num_recorded_frames == 0x7ffff)
                            num_recorded_frames = 0;

                        /* Also, if we have been prerecording, the frame count
                           will be wrong */
                        if(prerecording)
                            num_recorded_frames = 0;
                        
                        /* saved_header is saved right before stopping
                           the MAS */
                        framelen = create_xing_header(mpeg_file, 0,
                                                      num_rec_bytes, mp3buf,
                                                      num_recorded_frames,
                                                      saved_header, NULL,
                                                      false);
                        
                        lseek(mpeg_file, MPEG_RESERVED_HEADER_SPACE-framelen,
                              SEEK_SET);
                        write(mpeg_file, mp3buf, framelen);
                        close(mpeg_file);
                    }
                    mpeg_file = -1;
                    
#ifdef DEBUG1
                    {
                        int i;
                        for(i = 0;i < 512;i++)
                        {
                            DEBUGF("%d - %d us (%d bytes)\n",
                                   timing_info[i*2],
                                   (timing_info[i*2+1] & 0xffff) *
                                   10000 / 13824,
                                   timing_info[i*2+1] >> 16);
                        }
                    }
#endif /* #ifdef DEBUG1 */

                    if(prerecording)
                    {
                        start_prerecording();
                    }
                    mpeg_stop_done = true;
                    break;

                case MPEG_NEW_FILE:
                    /* Make sure we have at least one complete frame
                       in the buffer. If we haven't recorded a single
                       frame within 200ms, the MAS is probably not recording
                       anything, and we bail out. */
                    countdown = 20;
                    amount_to_save = get_unsaved_space();
                    while(countdown-- && amount_to_save < 1800)
                    {
                        sleep(HZ/10);
                        amount_to_save = get_unsaved_space();
                    }

                    if(amount_to_save >= 1800)
                    {
                        /* Now find a frame boundary to split at */
                        startpos = mp3buf_write - 1800;
                        if(startpos < 0)
                            startpos += mp3buflen;

                        saved_header = get_last_recorded_header();
                        
                        rc = mem_find_next_frame(startpos, &offset, 1800,
                                                 saved_header);
                        if(rc) /* Header found? */
                        {
                            /* offset will now contain the number of bytes to
                               add to startpos to find the frame boundary */
                            startpos += offset;
                            if(startpos >= mp3buflen)
                                startpos -= mp3buflen;
                        }
                        else
                        {
                            /* No header found. Let's save the whole buffer. */
                            startpos = mp3buf_write;
                        }
                    }
                    else
                    {
                        /* Too few bytes recorded, timeout */
                        startpos = mp3buf_write;
                    }
                    
                    amount_to_save = startpos - mp3buf_read;
                        if(amount_to_save < 0)
                            amount_to_save += mp3buflen;

                    /* First save up to the end of the buffer */
                    writelen = MIN(amount_to_save,
                                   mp3buflen - mp3buf_read);
                    
                    if (mpeg_file < 0) /* delayed file opening */
                    {
                        mpeg_file = open(delayed_filename, O_WRONLY|O_CREAT);
                    
                        if(mpeg_file < 0)
                            panicf("recfile: %d", mpeg_file);
                    }

                    if(writelen)
                    {
                        rc = write(mpeg_file, mp3buf + mp3buf_read, writelen);
                        if(rc < 0)
                        {
                            if(errno == ENOSPC)
                            {
                                mpeg_errno = MPEGERR_DISK_FULL;
                                demand_irq_enable(false);
                                stop_recording();
                                queue_post(&mpeg_queue, MPEG_STOP_DONE, 0);
                                break;
                            }
                            else
                            {
                                panicf("spt wrt: %d", rc);
                            }
                        }
                    }

                    /* Then save the rest */
                    writelen =  amount_to_save - writelen;
                    if(writelen)
                    {
                        rc = write(mpeg_file, mp3buf, writelen);
                        if(rc < 0)
                        {
                            if(errno == ENOSPC)
                            {
                                mpeg_errno = MPEGERR_DISK_FULL;
                                demand_irq_enable(false);
                                stop_recording();
                                queue_post(&mpeg_queue, MPEG_STOP_DONE, 0);
                                break;
                            }
                            else
                            {
                                panicf("spt wrt: %d", rc);
                            }
                        }
                    }

                    /* Advance the buffer pointers */
                    mp3buf_read += amount_to_save;
                    if(mp3buf_read >= mp3buflen)
                        mp3buf_read -= mp3buflen;

                    /* Close the current file */
                    rc = close(mpeg_file);
                    if(rc < 0)
                        panicf("spt cls: %d", rc);

                    /* Open the new file */
                    mpeg_file = open(recording_filename, O_WRONLY|O_CREAT);
                    if(mpeg_file < 0)
                        panicf("sptfile: %d", mpeg_file);
                    break;
                    
                case MPEG_SAVE_DATA:
                    amount_to_save = get_unsaved_space();
                    
                    /* If the result is negative, the write index has
                       wrapped */
                    if(amount_to_save < 0)
                    {
                        amount_to_save += mp3buflen;
                    }
                    
                    DEBUGF("r: %x w: %x\n", mp3buf_read, mp3buf_write);
                    DEBUGF("ats: %x\n", amount_to_save);
                    /* Save data only if the buffer is getting full,
                       or if we should stop recording */
                    if(amount_to_save)
                    {
                        if(mp3buflen -
                           amount_to_save < MPEG_RECORDING_LOW_WATER ||
                           stop_pending)
                        {
                            /* Only save up to the end of the buffer */
                            writelen = MIN(amount_to_save,
                                           mp3buflen - mp3buf_read);
                            
                            DEBUGF("wrl: %x\n", writelen);
                            
                            if (mpeg_file < 0) /* delayed file opening */
                            {
                                mpeg_file = open(delayed_filename,
                                    O_WRONLY|O_CREAT);
                    
                                if(mpeg_file < 0)
                                    panicf("recfile: %d", mpeg_file);
                            }

                            rc = write(mpeg_file, mp3buf + mp3buf_read,
                                       writelen);
                            
                            if(rc < 0)
                            {
                                if(errno == ENOSPC)
                                {
                                    mpeg_errno = MPEGERR_DISK_FULL;
                                    stop_recording();
                                    queue_post(&mpeg_queue, MPEG_STOP_DONE, 0);
                                    break;
                                }
                                else
                                {
                                    panicf("rec wrt: %d", rc);
                                }
                            }
                            
                            mp3buf_read += amount_to_save;
                            if(mp3buf_read >= mp3buflen)
                                mp3buf_read = 0;
                            
                            rc = fsync(mpeg_file);
                            if(rc < 0)
                                panicf("rec fls: %d", rc);

                            queue_post(&mpeg_queue, MPEG_SAVE_DATA, 0);
                        }
                        else
                        {
                            saving = false;
                            ata_sleep();
                        }
                    }
                    else
                    {
                        /* We have saved all data,
                           time to stop for real */
                        if(stop_pending)
                            queue_post(&mpeg_queue, MPEG_STOP_DONE, 0);
                        saving = false;
                        ata_sleep();
                    }
                    break;
                    
                case MPEG_INIT_PLAYBACK:
                    /* Stop the prerecording */ 
                    stop_recording();
                    mp3_play_init();
                    init_playback_done = true;
                    break;

                case SYS_USB_CONNECTED:
                    /* We can safely go to USB mode if no recording
                       is taking place */
                    if((!is_recording || is_prerecording) && mpeg_stop_done)
                    {
                        /* Even if we aren't recording, we still call this
                           function, to put the MAS in monitoring mode,
                           to save power. */
                        stop_recording();
                
                        /* Tell the USB thread that we are safe */
                        DEBUGF("mpeg_thread got SYS_USB_CONNECTED\n");
                        usb_acknowledge(SYS_USB_CONNECTED_ACK);
                    
                        /* Wait until the USB cable is extracted again */
                        usb_wait_for_disconnect(&mpeg_queue);
                    }
                    break;
            }
        }
#endif /* #ifdef HAVE_MAS3587F */
    }
}
#endif /* SIMULATOR */

#ifdef SIMULATOR
static struct mp3entry taginfo;
#endif /* #ifdef SIMULATOR */

struct mp3entry* mpeg_current_track()
{
#ifdef SIMULATOR
    return &taginfo;
#else
    if(num_tracks_in_memory())
        return &(id3tags[tag_read_idx]->id3);
    else
        return NULL;
#endif /* #ifdef SIMULATOR */
}

struct mp3entry* mpeg_next_track()
{
#ifdef SIMULATOR
    return &taginfo;
#else
    if(num_tracks_in_memory() > 1)
        return &(id3tags[(tag_read_idx+1) & MAX_ID3_TAGS_MASK]->id3);
    else
        return NULL;
#endif /* #ifdef SIMULATOR */
}

bool mpeg_has_changed_track(void)
{
    if(last_track_counter != current_track_counter)
    {
        last_track_counter = current_track_counter;
        return true;
    }
    return false;
}

#ifdef HAVE_MAS3587F
void mpeg_init_playback(void)
{
    init_playback_done = false;
    queue_post(&mpeg_queue, MPEG_INIT_PLAYBACK, NULL);

    while(!init_playback_done)
        sleep_thread();
    wake_up_thread();
}


/****************************************************************************
 **
 **
 ** Recording functions
 **
 **
 ***************************************************************************/
void mpeg_init_recording(void)
{
    init_recording_done = false;
    queue_post(&mpeg_queue, MPEG_INIT_RECORDING, NULL);

    while(!init_recording_done)
        sleep_thread();
    wake_up_thread();
}

static void init_recording(void)
{
    unsigned long val;
    int rc;

    /* Disable IRQ6 */
    IPRB &= 0xff0f;

    stop_playing();
    is_playing = false;
    paused = false;

    reset_mp3_buffer();
    remove_all_tags();
    
    if(mpeg_file >= 0)
        close(mpeg_file);
    mpeg_file = -1;

    /* Init the recording variables */
    is_recording = false;
    is_prerecording = false;

    mpeg_stop_done = true;
    
    mas_reset();
    
    /* Enable the audio CODEC and the DSP core, max analog voltage range */
    rc = mas_direct_config_write(MAS_CONTROL, 0x8c00);
    if(rc < 0)
        panicf("mas_ctrl_w: %d", rc);

    /* Stop the current application */
    val = 0;
    mas_writemem(MAS_BANK_D0,0x7f6,&val,1);    
    do
    {
        mas_readmem(MAS_BANK_D0, 0x7f7, &val, 1);
    } while(val);

    /* Perform black magic as described by the data sheet */
    if((mas_version_code & 0xff) == 2)
    {
        DEBUGF("Performing MAS black magic for B2 version\n");
        mas_writereg(0xa3, 0x98);
        mas_writereg(0x94, 0xfffff);
        val = 0;
        mas_writemem(MAS_BANK_D1, 0, &val, 1);
        mas_writereg(0xa3, 0x90);
    }

    /* Enable A/D Converters */
    mas_codec_writereg(0x0, 0xcccd);

    /* Copy left channel to right (mono mode) */
    mas_codec_writereg(8, 0x8000);
    
    /* ADC scale 0%, DSP scale 100%
       We use the DSP output for monitoring, because it works with all
       sources including S/PDIF */
    mas_codec_writereg(6, 0x0000);
    mas_codec_writereg(7, 0x4000);

    /* No mute */
    val = 0;
    mas_writemem(MAS_BANK_D0, 0x7f9, &val, 1);
    
    /* Set Demand mode, no monitoring and validate all settings */
    val = 0x125;
    mas_writemem(MAS_BANK_D0, 0x7f1, &val, 1);

    /* Start the encoder application */
    val = 0x40;
    mas_writemem(MAS_BANK_D0, 0x7f6, &val, 1);
    do
    {
        mas_readmem(MAS_BANK_D0, 0x7f7, &val, 1);
    } while(!(val & 0x40));

    /* We have started the recording application with monitoring OFF.
       This is because we want to record at least one frame to fill the DMA
       buffer, because the silly MAS will not negate EOD until at least one
       DMA transfer has taken place.
       Now let's wait for some data to be encoded. */
    sleep(20);
    
    /* Now set it to Monitoring mode as default, saves power */
    val = 0x525;
    mas_writemem(MAS_BANK_D0, 0x7f1, &val, 1);

    mpeg_mode = MPEG_ENCODER;

    DEBUGF("MAS Recording application started\n");

    /* At this point, all settings are the reset MAS defaults, next thing is to
       call mpeg_set_recording_options(). */
}

void mpeg_record(char *filename)
{
    mpeg_errno = 0;
    
    strncpy(recording_filename, filename, MAX_PATH - 1);
    recording_filename[MAX_PATH - 1] = 0;
    
    disable_xing_header = false;
    talk_buffer_steal(); /* we use the mp3 buffer, need to tell */
    queue_post(&mpeg_queue, MPEG_RECORD, NULL);
}

static void start_prerecording(void)
{
    unsigned long val;

    DEBUGF("Starting prerecording\n");
    
    prerecord_index = 0;
    prerecord_count = 0;
    prerecord_timeout = current_tick + HZ;
    memset(prerecord_buffer, 0, sizeof(prerecord_buffer));
    reset_mp3_buffer();
    talk_buffer_steal(); /* we use the mp3 buffer, need to tell */
    
    is_prerecording = true;

    /* Stop monitoring and start the encoder */
    mas_readmem(MAS_BANK_D0, 0x7f1, &val, 1);
    val &= ~(1 << 10);
    val |= 1;
    mas_writemem(MAS_BANK_D0, 0x7f1, &val, 1);
    DEBUGF("mas_writemem(MAS_BANK_D0, 0x7f1, %x)\n", val);

    /* Wait until the DSP has accepted the settings */
    do
    {
        mas_readmem(MAS_BANK_D0, 0x7f1, &val,1);
    } while(val & 1);
    
    sleep(20);

    is_recording = true;
    stop_pending = false;
    saving = false;

    demand_irq_enable(true);
}

static void start_recording(void)
{
    unsigned long val;

    num_recorded_frames = 0;

    if(is_prerecording)
    {
        /* This will make the IRQ handler start recording
           for real, i.e send MPEG_SAVE_DATA messages when
           the buffer is full */
        is_prerecording = false;
    }
    else
    {
        /* If prerecording is off, we need to stop the monitoring
           and start the encoder */
        mas_readmem(MAS_BANK_D0, 0x7f1, &val, 1);
        val &= ~(1 << 10);
        val |= 1;
        mas_writemem(MAS_BANK_D0, 0x7f1, &val, 1);
        DEBUGF("mas_writemem(MAS_BANK_D0, 0x7f1, %x)\n", val);
        
        /* Wait until the DSP has accepted the settings */
        do
        {
            mas_readmem(MAS_BANK_D0, 0x7f1, &val,1);
        } while(val & 1);
        
        sleep(20);
    }
    
    is_recording = true;
    stop_pending = false;
    saving = false;

    /* Store the current time */
    if(prerecording)
        record_start_time = current_tick - prerecord_count * HZ;
    else
        record_start_time = current_tick;
        
    demand_irq_enable(true);
}

static void stop_recording(void)
{
    unsigned long val;

    demand_irq_enable(false);

    is_recording = false;
    is_prerecording = false;
        
    /* Read the number of frames recorded */
    mas_readmem(MAS_BANK_D0, 0xfd0, &num_recorded_frames, 1);

    /* Start monitoring */
    mas_readmem(MAS_BANK_D0, 0x7f1, &val, 1);
    val |= (1 << 10) | 1;
    mas_writemem(MAS_BANK_D0, 0x7f1, &val, 1);
    DEBUGF("mas_writemem(MAS_BANK_D0, 0x7f1, %x)\n", val);
    
    /* Wait until the DSP has accepted the settings */
    do
    {
        mas_readmem(MAS_BANK_D0, 0x7f1, &val,1);
    } while(val & 1);
    
    drain_dma_buffer();
}

void mpeg_set_recording_options(int frequency, int quality,
                                int source, int channel_mode,
                                bool editable, int prerecord_time)
{
    bool is_mpeg1;
    unsigned long val;

    is_mpeg1 = (frequency < 3)?true:false;

    rec_version_index = is_mpeg1?3:2;
    rec_frequency_index = frequency % 3;
    
    val = (quality << 17) |
        (rec_frequency_index << 10) |
        ((is_mpeg1?1:0) << 9) |
        (1 << 8) | /* CRC on */
        (((channel_mode * 2 + 1) & 3) << 6) |
        (1 << 5) /* MS-stereo */ |
        (1 << 2) /* Is an original */;
    mas_writemem(MAS_BANK_D0, 0x7f0, &val,1);

    DEBUGF("mas_writemem(MAS_BANK_D0, 0x7f0, %x)\n", val);

    val = editable?4:0;
    mas_writemem(MAS_BANK_D0, 0x7f9, &val,1);

    DEBUGF("mas_writemem(MAS_BANK_D0, 0x7f9, %x)\n", val);

    val = (((source < 2)?1:2) << 8) | /* Input select */
        (1 << 5) | /* SDO strobe invert */
        ((is_mpeg1?0:1) << 3) |
        (1 << 2) | /* Inverted SIBC clock signal */
        1; /* Validate */
    mas_writemem(MAS_BANK_D0, 0x7f1, &val,1);

    DEBUGF("mas_writemem(MAS_BANK_D0, 0x7f1, %x)\n", val);

    drain_dma_buffer();
    
    if(source == 0) /* Mic */
    {
        /* Copy left channel to right (mono mode) */
        mas_codec_writereg(8, 0x8000);
    }
    else
    {
        /* Stereo input mode */
        mas_codec_writereg(8, 0);
    }

    prerecording_max_seconds = prerecord_time;
    if(prerecording_max_seconds)
    {
        prerecording = true;
        start_prerecording();
    }
    else
    {
        prerecording = false;
        is_prerecording = false;
        is_recording = false;
    }
}

/* If use_mic is true, the left gain is used */
void mpeg_set_recording_gain(int left, int right, bool use_mic)
{
    /* Enable both left and right A/D */
    mas_codec_writereg(0x0,
                       (left << 12) |
                       (right << 8) |
                       (left << 4) |
                       (use_mic?0x0008:0) | /* Connect left A/D to mic */
                       0x0007);
}

void mpeg_new_file(char *filename)
{
    mpeg_errno = 0;
    
    strncpy(recording_filename, filename, MAX_PATH - 1);
    recording_filename[MAX_PATH - 1] = 0;

    num_rec_bytes = 0;
    disable_xing_header = true;

    /* Store the current time */
    record_start_time = current_tick;

    queue_post(&mpeg_queue, MPEG_NEW_FILE, NULL);
}

unsigned long mpeg_recorded_time(void)
{
    if(is_prerecording)
        return prerecord_count * HZ;
    
    if(is_recording)
        return current_tick - record_start_time;

    return 0;
}

unsigned long mpeg_num_recorded_bytes(void)
{
    int num_bytes;
    int index;
    
    if(is_recording)
    {
        if(is_prerecording)
        {
            index = prerecord_index - prerecord_count;
            if(index < 0)
                index += prerecording_max_seconds;
            
            num_bytes = mp3buf_write - prerecord_buffer[index];
            if(num_bytes < 0)
                num_bytes += mp3buflen;
            
            return num_bytes;;
        }
        else
            return num_rec_bytes;
    }
    else
        return 0;
}

#endif

void mpeg_play(int offset)
{
#ifdef SIMULATOR
    char* trackname;
    int steps=0;

    is_playing = true;
    
    do {
        trackname = playlist_peek( steps );
        if (!trackname)
            break;
        if(mp3info(&taginfo, trackname)) {
            /* bad mp3, move on */
            if(++steps > playlist_amount())
                break;
            continue;
        }
        playlist_next(steps);
        taginfo.offset = offset;
        set_elapsed(&taginfo);
        is_playing = true;
        playing = true;
        break;
    } while(1);
#else
    is_playing = true;
    
    talk_buffer_steal(); /* we use the mp3 buffer, need to tell */
    queue_post(&mpeg_queue, MPEG_PLAY, (void*)offset);
#endif /* #ifdef SIMULATOR */

    mpeg_errno = 0;
}

void mpeg_stop(void)
{
#ifndef SIMULATOR
    mpeg_stop_done = false;
    queue_post(&mpeg_queue, MPEG_STOP, NULL);
    while(!mpeg_stop_done)
        yield();
#else
    paused = false;
    is_playing = false;
    playing = false;
#endif /* #ifndef SIMULATOR */
    
}

void mpeg_pause(void)
{
#ifndef SIMULATOR
    queue_post(&mpeg_queue, MPEG_PAUSE, NULL);
#else
    is_playing = true;
    playing = false;
    paused = true;
#endif /* #ifndef SIMULATOR */
}

void mpeg_resume(void)
{
#ifndef SIMULATOR
    queue_post(&mpeg_queue, MPEG_RESUME, NULL);
#else
    is_playing = true;
    playing = true;
    paused = false;
#endif /* #ifndef SIMULATOR */
}

void mpeg_next(void)
{
#ifndef SIMULATOR
    queue_post(&mpeg_queue, MPEG_NEXT, NULL);
#else
    char* file;
    int steps = 1;
    int index;

    do {
        file = playlist_peek(steps);
        if(!file)
            break;
        if(mp3info(&taginfo, file)) {
            if(++steps > playlist_amount())
                break;
            continue;
        }
        index = playlist_next(steps);
        taginfo.index = index;
        current_track_counter++;
        is_playing = true;
        playing = true;
        break;
    } while(1);
#endif /* #ifndef SIMULATOR */
}

void mpeg_prev(void)
{
#ifndef SIMULATOR
    queue_post(&mpeg_queue, MPEG_PREV, NULL);
#else
    char* file;
    int steps = -1;
    int index;

    do {
        file = playlist_peek(steps);
        if(!file)
            break;
        if(mp3info(&taginfo, file)) {
            steps--;
            continue;
        }
        index = playlist_next(steps);
        taginfo.index = index;
        current_track_counter++;
        is_playing = true;
        playing = true;
        break;
    } while(1);
#endif /* #ifndef SIMULATOR */
}

void mpeg_ff_rewind(int newtime)
{
#ifndef SIMULATOR
    queue_post(&mpeg_queue, MPEG_FF_REWIND, (void *)newtime);
#else
    (void)newtime;
#endif /* #ifndef SIMULATOR */
}

void mpeg_flush_and_reload_tracks(void)
{
#ifndef SIMULATOR
    queue_post(&mpeg_queue, MPEG_FLUSH_RELOAD, NULL);
#endif /* #ifndef SIMULATOR*/
}

int mpeg_status(void)
{
    int ret = 0;

    if(is_playing)
        ret |= MPEG_STATUS_PLAY;

    if(paused)
        ret |= MPEG_STATUS_PAUSE;
    
#ifdef HAVE_MAS3587F
    if(is_recording && !is_prerecording)
        ret |= MPEG_STATUS_RECORD;

    if(is_prerecording)
        ret |= MPEG_STATUS_PRERECORD;
#endif /* #ifdef HAVE_MAS3587F */

    if(mpeg_errno)
        ret |= MPEG_STATUS_ERROR;
    
    return ret;
}

unsigned int mpeg_error(void)
{
    return mpeg_errno;
}

void mpeg_error_clear(void)
{
    mpeg_errno = 0;
}

#ifdef SIMULATOR
static char mpeg_stack[DEFAULT_STACK_SIZE];
static char mpeg_thread_name[] = "mpeg";
static void mpeg_thread(void)
{
    struct mp3entry* id3;
    while ( 1 ) {
        if (is_playing) {
            id3 = mpeg_current_track();
            if (!paused)
            {
                id3->elapsed+=1000;
                id3->offset+=1000;
            }
            if (id3->elapsed>=id3->length)
                mpeg_next();
        }
        sleep(HZ);
    }
}
#endif /* #ifdef SIMULATOR */

void mpeg_init(void)
{
    mpeg_errno = 0;

#ifndef SIMULATOR
    mp3buflen = mp3end - mp3buf;
    queue_init(&mpeg_queue);
#endif /* #ifndef SIMULATOR */
    create_thread(mpeg_thread, mpeg_stack,
                  sizeof(mpeg_stack), mpeg_thread_name);

    memset(id3tags, sizeof(id3tags), 0);
    memset(_id3tags, sizeof(id3tags), 0);

#ifdef HAVE_MAS3587F
    if(read_hw_mask() & PR_ACTIVE_HIGH)
        inverted_pr = true;
    else
        inverted_pr = false;
#endif /* #ifdef HAVE_MAS3587F */
    
#ifdef DEBUG
    dbg_timer_start();
    dbg_cnt2us(0);
#endif /* DEBUG */
}