aboutsummaryrefslogtreecommitdiff
path: root/sound/pci/nm256/nm256.c
blob: c6c45d979f7a3b66f1172c417e69a61f41d06956 (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
/* 
 * Driver for NeoMagic 256AV and 256ZX chipsets.
 * Copyright (c) 2000 by Takashi Iwai <tiwai@suse.de>
 *
 * Based on nm256_audio.c OSS driver in linux kernel.
 * The original author of OSS nm256 driver wishes to remain anonymous,
 * so I just put my acknoledgment to him/her here.
 * The original author's web page is found at
 *	http://www.uglx.org/sony.html
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */
  
#include <asm/io.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/mutex.h>

#include <sound/core.h>
#include <sound/info.h>
#include <sound/control.h>
#include <sound/pcm.h>
#include <sound/ac97_codec.h>
#include <sound/initval.h>

#define CARD_NAME "NeoMagic 256AV/ZX"
#define DRIVER_NAME "NM256"

MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
MODULE_DESCRIPTION("NeoMagic NM256AV/ZX");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{NeoMagic,NM256AV},"
		"{NeoMagic,NM256ZX}}");

/*
 * some compile conditions.
 */

static int index = SNDRV_DEFAULT_IDX1;	/* Index */
static char *id = SNDRV_DEFAULT_STR1;	/* ID for this card */
static int playback_bufsize = 16;
static int capture_bufsize = 16;
static int force_ac97;			/* disabled as default */
static int buffer_top;			/* not specified */
static int use_cache;			/* disabled */
static int vaio_hack;			/* disabled */
static int reset_workaround;
static int reset_workaround_2;

module_param(index, int, 0444);
MODULE_PARM_DESC(index, "Index value for " CARD_NAME " soundcard.");
module_param(id, charp, 0444);
MODULE_PARM_DESC(id, "ID string for " CARD_NAME " soundcard.");
module_param(playback_bufsize, int, 0444);
MODULE_PARM_DESC(playback_bufsize, "DAC frame size in kB for " CARD_NAME " soundcard.");
module_param(capture_bufsize, int, 0444);
MODULE_PARM_DESC(capture_bufsize, "ADC frame size in kB for " CARD_NAME " soundcard.");
module_param(force_ac97, bool, 0444);
MODULE_PARM_DESC(force_ac97, "Force to use AC97 codec for " CARD_NAME " soundcard.");
module_param(buffer_top, int, 0444);
MODULE_PARM_DESC(buffer_top, "Set the top address of audio buffer for " CARD_NAME " soundcard.");
module_param(use_cache, bool, 0444);
MODULE_PARM_DESC(use_cache, "Enable the cache for coefficient table access.");
module_param(vaio_hack, bool, 0444);
MODULE_PARM_DESC(vaio_hack, "Enable workaround for Sony VAIO notebooks.");
module_param(reset_workaround, bool, 0444);
MODULE_PARM_DESC(reset_workaround, "Enable AC97 RESET workaround for some laptops.");
module_param(reset_workaround_2, bool, 0444);
MODULE_PARM_DESC(reset_workaround_2, "Enable extended AC97 RESET workaround for some other laptops.");

/* just for backward compatibility */
static int enable;
module_param(enable, bool, 0444);



/*
 * hw definitions
 */

/* The BIOS signature. */
#define NM_SIGNATURE 0x4e4d0000
/* Signature mask. */
#define NM_SIG_MASK 0xffff0000

/* Size of the second memory area. */
#define NM_PORT2_SIZE 4096

/* The base offset of the mixer in the second memory area. */
#define NM_MIXER_OFFSET 0x600

/* The maximum size of a coefficient entry. */
#define NM_MAX_PLAYBACK_COEF_SIZE	0x5000
#define NM_MAX_RECORD_COEF_SIZE		0x1260

/* The interrupt register. */
#define NM_INT_REG 0xa04
/* And its bits. */
#define NM_PLAYBACK_INT 0x40
#define NM_RECORD_INT 0x100
#define NM_MISC_INT_1 0x4000
#define NM_MISC_INT_2 0x1
#define NM_ACK_INT(chip, X) snd_nm256_writew(chip, NM_INT_REG, (X) << 1)

/* The AV's "mixer ready" status bit and location. */
#define NM_MIXER_STATUS_OFFSET 0xa04
#define NM_MIXER_READY_MASK 0x0800
#define NM_MIXER_PRESENCE 0xa06
#define NM_PRESENCE_MASK 0x0050
#define NM_PRESENCE_VALUE 0x0040

/*
 * For the ZX.  It uses the same interrupt register, but it holds 32
 * bits instead of 16.
 */
#define NM2_PLAYBACK_INT 0x10000
#define NM2_RECORD_INT 0x80000
#define NM2_MISC_INT_1 0x8
#define NM2_MISC_INT_2 0x2
#define NM2_ACK_INT(chip, X) snd_nm256_writel(chip, NM_INT_REG, (X))

/* The ZX's "mixer ready" status bit and location. */
#define NM2_MIXER_STATUS_OFFSET 0xa06
#define NM2_MIXER_READY_MASK 0x0800

/* The playback registers start from here. */
#define NM_PLAYBACK_REG_OFFSET 0x0
/* The record registers start from here. */
#define NM_RECORD_REG_OFFSET 0x200

/* The rate register is located 2 bytes from the start of the register area. */
#define NM_RATE_REG_OFFSET 2

/* Mono/stereo flag, number of bits on playback, and rate mask. */
#define NM_RATE_STEREO 1
#define NM_RATE_BITS_16 2
#define NM_RATE_MASK 0xf0

/* Playback enable register. */
#define NM_PLAYBACK_ENABLE_REG (NM_PLAYBACK_REG_OFFSET + 0x1)
#define NM_PLAYBACK_ENABLE_FLAG 1
#define NM_PLAYBACK_ONESHOT 2
#define NM_PLAYBACK_FREERUN 4

/* Mutes the audio output. */
#define NM_AUDIO_MUTE_REG (NM_PLAYBACK_REG_OFFSET + 0x18)
#define NM_AUDIO_MUTE_LEFT 0x8000
#define NM_AUDIO_MUTE_RIGHT 0x0080

/* Recording enable register. */
#define NM_RECORD_ENABLE_REG (NM_RECORD_REG_OFFSET + 0)
#define NM_RECORD_ENABLE_FLAG 1
#define NM_RECORD_FREERUN 2

/* coefficient buffer pointer */
#define NM_COEFF_START_OFFSET	0x1c
#define NM_COEFF_END_OFFSET	0x20

/* DMA buffer offsets */
#define NM_RBUFFER_START (NM_RECORD_REG_OFFSET + 0x4)
#define NM_RBUFFER_END   (NM_RECORD_REG_OFFSET + 0x10)
#define NM_RBUFFER_WMARK (NM_RECORD_REG_OFFSET + 0xc)
#define NM_RBUFFER_CURRP (NM_RECORD_REG_OFFSET + 0x8)

#define NM_PBUFFER_START (NM_PLAYBACK_REG_OFFSET + 0x4)
#define NM_PBUFFER_END   (NM_PLAYBACK_REG_OFFSET + 0x14)
#define NM_PBUFFER_WMARK (NM_PLAYBACK_REG_OFFSET + 0xc)
#define NM_PBUFFER_CURRP (NM_PLAYBACK_REG_OFFSET + 0x8)

struct nm256_stream {

	struct nm256 *chip;
	struct snd_pcm_substream *substream;
	int running;
	int suspended;
	
	u32 buf;	/* offset from chip->buffer */
	int bufsize;	/* buffer size in bytes */
	void __iomem *bufptr;		/* mapped pointer */
	unsigned long bufptr_addr;	/* physical address of the mapped pointer */

	int dma_size;		/* buffer size of the substream in bytes */
	int period_size;	/* period size in bytes */
	int periods;		/* # of periods */
	int shift;		/* bit shifts */
	int cur_period;		/* current period # */

};

struct nm256 {
	
	struct snd_card *card;

	void __iomem *cport;		/* control port */
	struct resource *res_cport;	/* its resource */
	unsigned long cport_addr;	/* physical address */

	void __iomem *buffer;		/* buffer */
	struct resource *res_buffer;	/* its resource */
	unsigned long buffer_addr;	/* buffer phyiscal address */

	u32 buffer_start;		/* start offset from pci resource 0 */
	u32 buffer_end;			/* end offset */
	u32 buffer_size;		/* total buffer size */

	u32 all_coeff_buf;		/* coefficient buffer */
	u32 coeff_buf[2];		/* coefficient buffer for each stream */

	unsigned int coeffs_current: 1;	/* coeff. table is loaded? */
	unsigned int use_cache: 1;	/* use one big coef. table */
	unsigned int reset_workaround: 1; /* Workaround for some laptops to avoid freeze */
	unsigned int reset_workaround_2: 1; /* Extended workaround for some other laptops to avoid freeze */
	unsigned int in_resume: 1;

	int mixer_base;			/* register offset of ac97 mixer */
	int mixer_status_offset;	/* offset of mixer status reg. */
	int mixer_status_mask;		/* bit mask to test the mixer status */

	int irq;
	int irq_acks;
	irq_handler_t interrupt;
	int badintrcount;		/* counter to check bogus interrupts */
	struct mutex irq_mutex;

	struct nm256_stream streams[2];

	struct snd_ac97 *ac97;
	unsigned short *ac97_regs; /* register caches, only for valid regs */

	struct snd_pcm *pcm;

	struct pci_dev *pci;

	spinlock_t reg_lock;

};


/*
 * include coefficient table
 */
#include "nm256_coef.c"


/*
 * PCI ids
 */
static DEFINE_PCI_DEVICE_TABLE(snd_nm256_ids) = {
	{PCI_VDEVICE(NEOMAGIC, PCI_DEVICE_ID_NEOMAGIC_NM256AV_AUDIO), 0},
	{PCI_VDEVICE(NEOMAGIC, PCI_DEVICE_ID_NEOMAGIC_NM256ZX_AUDIO), 0},
	{PCI_VDEVICE(NEOMAGIC, PCI_DEVICE_ID_NEOMAGIC_NM256XL_PLUS_AUDIO), 0},
	{0,},
};

MODULE_DEVICE_TABLE(pci, snd_nm256_ids);


/*
 * lowlvel stuffs
 */

static inline u8
snd_nm256_readb(struct nm256 *chip, int offset)
{
	return readb(chip->cport + offset);
}

static inline u16
snd_nm256_readw(struct nm256 *chip, int offset)
{
	return readw(chip->cport + offset);
}

static inline u32
snd_nm256_readl(struct nm256 *chip, int offset)
{
	return readl(chip->cport + offset);
}

static inline void
snd_nm256_writeb(struct nm256 *chip, int offset, u8 val)
{
	writeb(val, chip->cport + offset);
}

static inline void
snd_nm256_writew(struct nm256 *chip, int offset, u16 val)
{
	writew(val, chip->cport + offset);
}

static inline void
snd_nm256_writel(struct nm256 *chip, int offset, u32 val)
{
	writel(val, chip->cport + offset);
}

static inline void
snd_nm256_write_buffer(struct nm256 *chip, void *src, int offset, int size)
{
	offset -= chip->buffer_start;
#ifdef CONFIG_SND_DEBUG
	if (offset < 0 || offset >= chip->buffer_size) {
		snd_printk(KERN_ERR "write_buffer invalid offset = %d size = %d\n",
			   offset, size);
		return;
	}
#endif
	memcpy_toio(chip->buffer + offset, src, size);
}

/*
 * coefficient handlers -- what a magic!
 */

static u16
snd_nm256_get_start_offset(int which)
{
	u16 offset = 0;
	while (which-- > 0)
		offset += coefficient_sizes[which];
	return offset;
}

static void
snd_nm256_load_one_coefficient(struct nm256 *chip, int stream, u32 port, int which)
{
	u32 coeff_buf = chip->coeff_buf[stream];
	u16 offset = snd_nm256_get_start_offset(which);
	u16 size = coefficient_sizes[which];

	snd_nm256_write_buffer(chip, coefficients + offset, coeff_buf, size);
	snd_nm256_writel(chip, port, coeff_buf);
	/* ???  Record seems to behave differently than playback.  */
	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
		size--;
	snd_nm256_writel(chip, port + 4, coeff_buf + size);
}

static void
snd_nm256_load_coefficient(struct nm256 *chip, int stream, int number)
{
	/* The enable register for the specified engine.  */
	u32 poffset = (stream == SNDRV_PCM_STREAM_CAPTURE ?
		       NM_RECORD_ENABLE_REG : NM_PLAYBACK_ENABLE_REG);
	u32 addr = NM_COEFF_START_OFFSET;

	addr += (stream == SNDRV_PCM_STREAM_CAPTURE ?
		 NM_RECORD_REG_OFFSET : NM_PLAYBACK_REG_OFFSET);

	if (snd_nm256_readb(chip, poffset) & 1) {
		snd_printd("NM256: Engine was enabled while loading coefficients!\n");
		return;
	}

	/* The recording engine uses coefficient values 8-15.  */
	number &= 7;
	if (stream == SNDRV_PCM_STREAM_CAPTURE)
		number += 8;

	if (! chip->use_cache) {
		snd_nm256_load_one_coefficient(chip, stream, addr, number);
		return;
	}
	if (! chip->coeffs_current) {
		snd_nm256_write_buffer(chip, coefficients, chip->all_coeff_buf,
				       NM_TOTAL_COEFF_COUNT * 4);
		chip->coeffs_current = 1;
	} else {
		u32 base = chip->all_coeff_buf;
		u32 offset = snd_nm256_get_start_offset(number);
		u32 end_offset = offset + coefficient_sizes[number];
		snd_nm256_writel(chip, addr, base + offset);
		if (stream == SNDRV_PCM_STREAM_PLAYBACK)
			end_offset--;
		snd_nm256_writel(chip, addr + 4, base + end_offset);
	}
}


/* The actual rates supported by the card. */
static unsigned int samplerates[8] = {
	8000, 11025, 16000, 22050, 24000, 32000, 44100, 48000,
};
static struct snd_pcm_hw_constraint_list constraints_rates = {
	.count = ARRAY_SIZE(samplerates), 
	.list = samplerates,
	.mask = 0,
};

/*
 * return the index of the target rate
 */
static int
snd_nm256_fixed_rate(unsigned int rate)
{
	unsigned int i;
	for (i = 0; i < ARRAY_SIZE(samplerates); i++) {
		if (rate == samplerates[i])
			return i;
	}
	snd_BUG();
	return 0;
}

/*
 * set sample rate and format
 */
static void
snd_nm256_set_format(struct nm256 *chip, struct nm256_stream *s,
		     struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	int rate_index = snd_nm256_fixed_rate(runtime->rate);
	unsigned char ratebits = (rate_index << 4) & NM_RATE_MASK;

	s->shift = 0;
	if (snd_pcm_format_width(runtime->format) == 16) {
		ratebits |= NM_RATE_BITS_16;
		s->shift++;
	}
	if (runtime->channels > 1) {
		ratebits |= NM_RATE_STEREO;
		s->shift++;
	}

	runtime->rate = samplerates[rate_index];

	switch (substream->stream) {
	case SNDRV_PCM_STREAM_PLAYBACK:
		snd_nm256_load_coefficient(chip, 0, rate_index); /* 0 = playback */
		snd_nm256_writeb(chip,
				 NM_PLAYBACK_REG_OFFSET + NM_RATE_REG_OFFSET,
				 ratebits);
		break;
	case SNDRV_PCM_STREAM_CAPTURE:
		snd_nm256_load_coefficient(chip, 1, rate_index); /* 1 = record */
		snd_nm256_writeb(chip,
				 NM_RECORD_REG_OFFSET + NM_RATE_REG_OFFSET,
				 ratebits);
		break;
	}
}

/* acquire interrupt */
static int snd_nm256_acquire_irq(struct nm256 *chip)
{
	mutex_lock(&chip->irq_mutex);
	if (chip->irq < 0) {
		if (request_irq(chip->pci->irq, chip->interrupt, IRQF_SHARED,
				KBUILD_MODNAME, chip)) {
			snd_printk(KERN_ERR "unable to grab IRQ %d\n", chip->pci->irq);
			mutex_unlock(&chip->irq_mutex);
			return -EBUSY;
		}
		chip->irq = chip->pci->irq;
	}
	chip->irq_acks++;
	mutex_unlock(&chip->irq_mutex);
	return 0;
}

/* release interrupt */
static void snd_nm256_release_irq(struct nm256 *chip)
{
	mutex_lock(&chip->irq_mutex);
	if (chip->irq_acks > 0)
		chip->irq_acks--;
	if (chip->irq_acks == 0 && chip->irq >= 0) {
		free_irq(chip->irq, chip);
		chip->irq = -1;
	}
	mutex_unlock(&chip->irq_mutex);
}

/*
 * start / stop
 */

/* update the watermark (current period) */
static void snd_nm256_pcm_mark(struct nm256 *chip, struct nm256_stream *s, int reg)
{
	s->cur_period++;
	s->cur_period %= s->periods;
	snd_nm256_writel(chip, reg, s->buf + s->cur_period * s->period_size);
}

#define snd_nm256_playback_mark(chip, s) snd_nm256_pcm_mark(chip, s, NM_PBUFFER_WMARK)
#define snd_nm256_capture_mark(chip, s)  snd_nm256_pcm_mark(chip, s, NM_RBUFFER_WMARK)

static void
snd_nm256_playback_start(struct nm256 *chip, struct nm256_stream *s,
			 struct snd_pcm_substream *substream)
{
	/* program buffer pointers */
	snd_nm256_writel(chip, NM_PBUFFER_START, s->buf);
	snd_nm256_writel(chip, NM_PBUFFER_END, s->buf + s->dma_size - (1 << s->shift));
	snd_nm256_writel(chip, NM_PBUFFER_CURRP, s->buf);
	snd_nm256_playback_mark(chip, s);

	/* Enable playback engine and interrupts. */
	snd_nm256_writeb(chip, NM_PLAYBACK_ENABLE_REG,
			 NM_PLAYBACK_ENABLE_FLAG | NM_PLAYBACK_FREERUN);
	/* Enable both channels. */
	snd_nm256_writew(chip, NM_AUDIO_MUTE_REG, 0x0);
}

static void
snd_nm256_capture_start(struct nm256 *chip, struct nm256_stream *s,
			struct snd_pcm_substream *substream)
{
	/* program buffer pointers */
	snd_nm256_writel(chip, NM_RBUFFER_START, s->buf);
	snd_nm256_writel(chip, NM_RBUFFER_END, s->buf + s->dma_size);
	snd_nm256_writel(chip, NM_RBUFFER_CURRP, s->buf);
	snd_nm256_capture_mark(chip, s);

	/* Enable playback engine and interrupts. */
	snd_nm256_writeb(chip, NM_RECORD_ENABLE_REG,
			 NM_RECORD_ENABLE_FLAG | NM_RECORD_FREERUN);
}

/* Stop the play engine. */
static void
snd_nm256_playback_stop(struct nm256 *chip)
{
	/* Shut off sound from both channels. */
	snd_nm256_writew(chip, NM_AUDIO_MUTE_REG,
			 NM_AUDIO_MUTE_LEFT | NM_AUDIO_MUTE_RIGHT);
	/* Disable play engine. */
	snd_nm256_writeb(chip, NM_PLAYBACK_ENABLE_REG, 0);
}

static void
snd_nm256_capture_stop(struct nm256 *chip)
{
	/* Disable recording engine. */
	snd_nm256_writeb(chip, NM_RECORD_ENABLE_REG, 0);
}

static int
snd_nm256_playback_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	int err = 0;

	if (snd_BUG_ON(!s))
		return -ENXIO;

	spin_lock(&chip->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_RESUME:
		s->suspended = 0;
		/* fallthru */
	case SNDRV_PCM_TRIGGER_START:
		if (! s->running) {
			snd_nm256_playback_start(chip, s, substream);
			s->running = 1;
		}
		break;
	case SNDRV_PCM_TRIGGER_SUSPEND:
		s->suspended = 1;
		/* fallthru */
	case SNDRV_PCM_TRIGGER_STOP:
		if (s->running) {
			snd_nm256_playback_stop(chip);
			s->running = 0;
		}
		break;
	default:
		err = -EINVAL;
		break;
	}
	spin_unlock(&chip->reg_lock);
	return err;
}

static int
snd_nm256_capture_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	int err = 0;

	if (snd_BUG_ON(!s))
		return -ENXIO;

	spin_lock(&chip->reg_lock);
	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
		if (! s->running) {
			snd_nm256_capture_start(chip, s, substream);
			s->running = 1;
		}
		break;
	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
		if (s->running) {
			snd_nm256_capture_stop(chip);
			s->running = 0;
		}
		break;
	default:
		err = -EINVAL;
		break;
	}
	spin_unlock(&chip->reg_lock);
	return err;
}


/*
 * prepare playback/capture channel
 */
static int snd_nm256_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;

	if (snd_BUG_ON(!s))
		return -ENXIO;
	s->dma_size = frames_to_bytes(runtime, substream->runtime->buffer_size);
	s->period_size = frames_to_bytes(runtime, substream->runtime->period_size);
	s->periods = substream->runtime->periods;
	s->cur_period = 0;

	spin_lock_irq(&chip->reg_lock);
	s->running = 0;
	snd_nm256_set_format(chip, s, substream);
	spin_unlock_irq(&chip->reg_lock);

	return 0;
}


/*
 * get the current pointer
 */
static snd_pcm_uframes_t
snd_nm256_playback_pointer(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	unsigned long curp;

	if (snd_BUG_ON(!s))
		return 0;
	curp = snd_nm256_readl(chip, NM_PBUFFER_CURRP) - (unsigned long)s->buf;
	curp %= s->dma_size;
	return bytes_to_frames(substream->runtime, curp);
}

static snd_pcm_uframes_t
snd_nm256_capture_pointer(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);
	struct nm256_stream *s = substream->runtime->private_data;
	unsigned long curp;

	if (snd_BUG_ON(!s))
		return 0;
	curp = snd_nm256_readl(chip, NM_RBUFFER_CURRP) - (unsigned long)s->buf;
	curp %= s->dma_size;	
	return bytes_to_frames(substream->runtime, curp);
}

/* Remapped I/O space can be accessible as pointer on i386 */
/* This might be changed in the future */
#ifndef __i386__
/*
 * silence / copy for playback
 */
static int
snd_nm256_playback_silence(struct snd_pcm_substream *substream,
			   int channel, /* not used (interleaved data) */
			   snd_pcm_uframes_t pos,
			   snd_pcm_uframes_t count)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;
	count = frames_to_bytes(runtime, count);
	pos = frames_to_bytes(runtime, pos);
	memset_io(s->bufptr + pos, 0, count);
	return 0;
}

static int
snd_nm256_playback_copy(struct snd_pcm_substream *substream,
			int channel, /* not used (interleaved data) */
			snd_pcm_uframes_t pos,
			void __user *src,
			snd_pcm_uframes_t count)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;
	count = frames_to_bytes(runtime, count);
	pos = frames_to_bytes(runtime, pos);
	if (copy_from_user_toio(s->bufptr + pos, src, count))
		return -EFAULT;
	return 0;
}

/*
 * copy to user
 */
static int
snd_nm256_capture_copy(struct snd_pcm_substream *substream,
		       int channel, /* not used (interleaved data) */
		       snd_pcm_uframes_t pos,
		       void __user *dst,
		       snd_pcm_uframes_t count)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct nm256_stream *s = runtime->private_data;
	count = frames_to_bytes(runtime, count);
	pos = frames_to_bytes(runtime, pos);
	if (copy_to_user_fromio(dst, s->bufptr + pos, count))
		return -EFAULT;
	return 0;
}

#endif /* !__i386__ */


/*
 * update playback/capture watermarks
 */

/* spinlock held! */
static void
snd_nm256_playback_update(struct nm256 *chip)
{
	struct nm256_stream *s;

	s = &chip->streams[SNDRV_PCM_STREAM_PLAYBACK];
	if (s->running && s->substream) {
		spin_unlock(&chip->reg_lock);
		snd_pcm_period_elapsed(s->substream);
		spin_lock(&chip->reg_lock);
		snd_nm256_playback_mark(chip, s);
	}
}

/* spinlock held! */
static void
snd_nm256_capture_update(struct nm256 *chip)
{
	struct nm256_stream *s;

	s = &chip->streams[SNDRV_PCM_STREAM_CAPTURE];
	if (s->running && s->substream) {
		spin_unlock(&chip->reg_lock);
		snd_pcm_period_elapsed(s->substream);
		spin_lock(&chip->reg_lock);
		snd_nm256_capture_mark(chip, s);
	}
}

/*
 * hardware info
 */
static struct snd_pcm_hardware snd_nm256_playback =
{
	.info =			SNDRV_PCM_INFO_MMAP_IOMEM |SNDRV_PCM_INFO_MMAP_VALID |
				SNDRV_PCM_INFO_INTERLEAVED |
				/*SNDRV_PCM_INFO_PAUSE |*/
				SNDRV_PCM_INFO_RESUME,
	.formats =		SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_KNOT/*24k*/ | SNDRV_PCM_RATE_8000_48000,
	.rate_min =		8000,
	.rate_max =		48000,
	.channels_min =		1,
	.channels_max =		2,
	.periods_min =		2,
	.periods_max =		1024,
	.buffer_bytes_max =	128 * 1024,
	.period_bytes_min =	256,
	.period_bytes_max =	128 * 1024,
};

static struct snd_pcm_hardware snd_nm256_capture =
{
	.info =			SNDRV_PCM_INFO_MMAP_IOMEM | SNDRV_PCM_INFO_MMAP_VALID |
				SNDRV_PCM_INFO_INTERLEAVED |
				/*SNDRV_PCM_INFO_PAUSE |*/
				SNDRV_PCM_INFO_RESUME,
	.formats =		SNDRV_PCM_FMTBIT_U8 | SNDRV_PCM_FMTBIT_S16_LE,
	.rates =		SNDRV_PCM_RATE_KNOT/*24k*/ | SNDRV_PCM_RATE_8000_48000,
	.rate_min =		8000,
	.rate_max =		48000,
	.channels_min =		1,
	.channels_max =		2,
	.periods_min =		2,
	.periods_max =		1024,
	.buffer_bytes_max =	128 * 1024,
	.period_bytes_min =	256,
	.period_bytes_max =	128 * 1024,
};


/* set dma transfer size */
static int snd_nm256_pcm_hw_params(struct snd_pcm_substream *substream,
				   struct snd_pcm_hw_params *hw_params)
{
	/* area and addr are already set and unchanged */
	substream->runtime->dma_bytes = params_buffer_bytes(hw_params);
	return 0;
}

/*
 * open
 */
static void snd_nm256_setup_stream(struct nm256 *chip, struct nm256_stream *s,
				   struct snd_pcm_substream *substream,
				   struct snd_pcm_hardware *hw_ptr)
{
	struct snd_pcm_runtime *runtime = substream->runtime;

	s->running = 0;
	runtime->hw = *hw_ptr;
	runtime->hw.buffer_bytes_max = s->bufsize;
	runtime->hw.period_bytes_max = s->bufsize / 2;
	runtime->dma_area = (void __force *) s->bufptr;
	runtime->dma_addr = s->bufptr_addr;
	runtime->dma_bytes = s->bufsize;
	runtime->private_data = s;
	s->substream = substream;

	snd_pcm_hw_constraint_list(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
				   &constraints_rates);
}

static int
snd_nm256_playback_open(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	if (snd_nm256_acquire_irq(chip) < 0)
		return -EBUSY;
	snd_nm256_setup_stream(chip, &chip->streams[SNDRV_PCM_STREAM_PLAYBACK],
			       substream, &snd_nm256_playback);
	return 0;
}

static int
snd_nm256_capture_open(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	if (snd_nm256_acquire_irq(chip) < 0)
		return -EBUSY;
	snd_nm256_setup_stream(chip, &chip->streams[SNDRV_PCM_STREAM_CAPTURE],
			       substream, &snd_nm256_capture);
	return 0;
}

/*
 * close - we don't have to do special..
 */
static int
snd_nm256_playback_close(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	snd_nm256_release_irq(chip);
	return 0;
}


static int
snd_nm256_capture_close(struct snd_pcm_substream *substream)
{
	struct nm256 *chip = snd_pcm_substream_chip(substream);

	snd_nm256_release_irq(chip);
	return 0;
}

/*
 * create a pcm instance
 */
static struct snd_pcm_ops snd_nm256_playback_ops = {
	.open =		snd_nm256_playback_open,
	.close =	snd_nm256_playback_close,
	.ioctl =	snd_pcm_lib_ioctl,
	.hw_params =	snd_nm256_pcm_hw_params,
	.prepare =	snd_nm256_pcm_prepare,
	.trigger =	snd_nm256_playback_trigger,
	.pointer =	snd_nm256_playback_pointer,
#ifndef __i386__
	.copy =		snd_nm256_playback_copy,
	.silence =	snd_nm256_playback_silence,
#endif
	.mmap =		snd_pcm_lib_mmap_iomem,
};

static struct snd_pcm_ops snd_nm256_capture_ops = {
	.open =		snd_nm256_capture_open,
	.close =	snd_nm256_capture_close,
	.ioctl =	snd_pcm_lib_ioctl,
	.hw_params =	snd_nm256_pcm_hw_params,
	.prepare =	snd_nm256_pcm_prepare,
	.trigger =	snd_nm256_capture_trigger,
	.pointer =	snd_nm256_capture_pointer,
#ifndef __i386__
	.copy =		snd_nm256_capture_copy,
#endif
	.mmap =		snd_pcm_lib_mmap_iomem,
};

static int __devinit
snd_nm256_pcm(struct nm256 *chip, int device)
{
	struct snd_pcm *pcm;
	int i, err;

	for (i = 0; i < 2; i++) {
		struct nm256_stream *s = &chip->streams[i];
		s->bufptr = chip->buffer + (s->buf - chip->buffer_start);
		s->bufptr_addr = chip->buffer_addr + (s->buf - chip->buffer_start);
	}

	err = snd_pcm_new(chip->card, chip->card->driver, device,
			  1, 1, &pcm);
	if (err < 0)
		return err;

	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_nm256_playback_ops);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_nm256_capture_ops);

	pcm->private_data = chip;
	pcm->info_flags = 0;
	chip->pcm = pcm;

	return 0;
}


/* 
 * Initialize the hardware. 
 */
static void
snd_nm256_init_chip(struct nm256 *chip)
{
	/* Reset everything. */
	snd_nm256_writeb(chip, 0x0, 0x11);
	snd_nm256_writew(chip, 0x214, 0);
	/* stop sounds.. */
	//snd_nm256_playback_stop(chip);
	//snd_nm256_capture_stop(chip);
}


static irqreturn_t
snd_nm256_intr_check(struct nm256 *chip)
{
	if (chip->badintrcount++ > 1000) {
		/*
		 * I'm not sure if the best thing is to stop the card from
		 * playing or just release the interrupt (after all, we're in
		 * a bad situation, so doing fancy stuff may not be such a good
		 * idea).
		 *
		 * I worry about the card engine continuing to play noise
		 * over and over, however--that could become a very
		 * obnoxious problem.  And we know that when this usually
		 * happens things are fairly safe, it just means the user's
		 * inserted a PCMCIA card and someone's spamming us with IRQ 9s.
		 */
		if (chip->streams[SNDRV_PCM_STREAM_PLAYBACK].running)
			snd_nm256_playback_stop(chip);
		if (chip->streams[SNDRV_PCM_STREAM_CAPTURE].running)
			snd_nm256_capture_stop(chip);
		chip->badintrcount = 0;
		return IRQ_HANDLED;
	}
	return IRQ_NONE;
}

/* 
 * Handle a potential interrupt for the device referred to by DEV_ID. 
 *
 * I don't like the cut-n-paste job here either between the two routines,
 * but there are sufficient differences between the two interrupt handlers
 * that parameterizing it isn't all that great either.  (Could use a macro,
 * I suppose...yucky bleah.)
 */

static irqreturn_t
snd_nm256_interrupt(int irq, void *dev_id)
{
	struct nm256 *chip = dev_id;
	u16 status;
	u8 cbyte;

	status = snd_nm256_readw(chip, NM_INT_REG);

	/* Not ours. */
	if (status == 0)
		return snd_nm256_intr_check(chip);

	chip->badintrcount = 0;

	/* Rather boring; check for individual interrupts and process them. */

	spin_lock(&chip->reg_lock);
	if (status & NM_PLAYBACK_INT) {
		status &= ~NM_PLAYBACK_INT;
		NM_ACK_INT(chip, NM_PLAYBACK_INT);
		snd_nm256_playback_update(chip);
	}

	if (status & NM_RECORD_INT) {
		status &= ~NM_RECORD_INT;
		NM_ACK_INT(chip, NM_RECORD_INT);
		snd_nm256_capture_update(chip);
	}

	if (status & NM_MISC_INT_1) {
		status &= ~NM_MISC_INT_1;
		NM_ACK_INT(chip, NM_MISC_INT_1);
		snd_printd("NM256: Got misc interrupt #1\n");
		snd_nm256_writew(chip, NM_INT_REG, 0x8000);
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte | 2);
	}

	if (status & NM_MISC_INT_2) {
		status &= ~NM_MISC_INT_2;
		NM_ACK_INT(chip, NM_MISC_INT_2);
		snd_printd("NM256: Got misc interrupt #2\n");
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte & ~2);
	}

	/* Unknown interrupt. */
	if (status) {
		snd_printd("NM256: Fire in the hole! Unknown status 0x%x\n",
			   status);
		/* Pray. */
		NM_ACK_INT(chip, status);
	}

	spin_unlock(&chip->reg_lock);
	return IRQ_HANDLED;
}

/*
 * Handle a potential interrupt for the device referred to by DEV_ID.
 * This handler is for the 256ZX, and is very similar to the non-ZX
 * routine.
 */

static irqreturn_t
snd_nm256_interrupt_zx(int irq, void *dev_id)
{
	struct nm256 *chip = dev_id;
	u32 status;
	u8 cbyte;

	status = snd_nm256_readl(chip, NM_INT_REG);

	/* Not ours. */
	if (status == 0)
		return snd_nm256_intr_check(chip);

	chip->badintrcount = 0;

	/* Rather boring; check for individual interrupts and process them. */

	spin_lock(&chip->reg_lock);
	if (status & NM2_PLAYBACK_INT) {
		status &= ~NM2_PLAYBACK_INT;
		NM2_ACK_INT(chip, NM2_PLAYBACK_INT);
		snd_nm256_playback_update(chip);
	}

	if (status & NM2_RECORD_INT) {
		status &= ~NM2_RECORD_INT;
		NM2_ACK_INT(chip, NM2_RECORD_INT);
		snd_nm256_capture_update(chip);
	}

	if (status & NM2_MISC_INT_1) {
		status &= ~NM2_MISC_INT_1;
		NM2_ACK_INT(chip, NM2_MISC_INT_1);
		snd_printd("NM256: Got misc interrupt #1\n");
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte | 2);
	}

	if (status & NM2_MISC_INT_2) {
		status &= ~NM2_MISC_INT_2;
		NM2_ACK_INT(chip, NM2_MISC_INT_2);
		snd_printd("NM256: Got misc interrupt #2\n");
		cbyte = snd_nm256_readb(chip, 0x400);
		snd_nm256_writeb(chip, 0x400, cbyte & ~2);
	}

	/* Unknown interrupt. */
	if (status) {
		snd_printd("NM256: Fire in the hole! Unknown status 0x%x\n",
			   status);
		/* Pray. */
		NM2_ACK_INT(chip, status);
	}

	spin_unlock(&chip->reg_lock);
	return IRQ_HANDLED;
}

/*
 * AC97 interface
 */

/*
 * Waits for the mixer to become ready to be written; returns a zero value
 * if it timed out.
 */
static int
snd_nm256_ac97_ready(struct nm256 *chip)
{
	int timeout = 10;
	u32 testaddr;
	u16 testb;

	testaddr = chip->mixer_status_offset;
	testb = chip->mixer_status_mask;

	/* 
	 * Loop around waiting for the mixer to become ready. 
	 */
	while (timeout-- > 0) {
		if ((snd_nm256_readw(chip, testaddr) & testb) == 0)
			return 1;
		udelay(100);
	}
	return 0;
}

/* 
 * Initial register values to be written to the AC97 mixer.
 * While most of these are identical to the reset values, we do this
 * so that we have most of the register contents cached--this avoids
 * reading from the mixer directly (which seems to be problematic,
 * probably due to ignorance).
 */

struct initialValues {
	unsigned short reg;
	unsigned short value;
};

static struct initialValues nm256_ac97_init_val[] =
{
	{ AC97_MASTER, 		0x8000 },
	{ AC97_HEADPHONE,	0x8000 },
	{ AC97_MASTER_MONO,	0x8000 },
	{ AC97_PC_BEEP,		0x8000 },
	{ AC97_PHONE,		0x8008 },
	{ AC97_MIC,		0x8000 },
	{ AC97_LINE,		0x8808 },
	{ AC97_CD,		0x8808 },
	{ AC97_VIDEO,		0x8808 },
	{ AC97_AUX,		0x8808 },
	{ AC97_PCM,		0x8808 },
	{ AC97_REC_SEL,		0x0000 },
	{ AC97_REC_GAIN,	0x0B0B },
	{ AC97_GENERAL_PURPOSE,	0x0000 },
	{ AC97_3D_CONTROL,	0x8000 }, 
	{ AC97_VENDOR_ID1, 	0x8384 },
	{ AC97_VENDOR_ID2,	0x7609 },
};

static int nm256_ac97_idx(unsigned short reg)
{
	int i;
	for (i = 0; i < ARRAY_SIZE(nm256_ac97_init_val); i++)
		if (nm256_ac97_init_val[i].reg == reg)
			return i;
	return -1;
}

/*
 * some nm256 easily crash when reading from mixer registers
 * thus we're treating it as a write-only mixer and cache the
 * written values
 */
static unsigned short
snd_nm256_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
{
	struct nm256 *chip = ac97->private_data;
	int idx = nm256_ac97_idx(reg);

	if (idx < 0)
		return 0;
	return chip->ac97_regs[idx];
}

/* 
 */
static void
snd_nm256_ac97_write(struct snd_ac97 *ac97,
		     unsigned short reg, unsigned short val)
{
	struct nm256 *chip = ac97->private_data;
	int tries = 2;
	int idx = nm256_ac97_idx(reg);
	u32 base;

	if (idx < 0)
		return;

	base = chip->mixer_base;

	snd_nm256_ac97_ready(chip);

	/* Wait for the write to take, too. */
	while (tries-- > 0) {
		snd_nm256_writew(chip, base + reg, val);
		msleep(1);  /* a little delay here seems better.. */
		if (snd_nm256_ac97_ready(chip)) {
			/* successful write: set cache */
			chip->ac97_regs[idx] = val;
			return;
		}
	}
	snd_printd("nm256: ac97 codec not ready..\n");
}

/* static resolution table */
static struct snd_ac97_res_table nm256_res_table[] = {
	{ AC97_MASTER, 0x1f1f },
	{ AC97_HEADPHONE, 0x1f1f },
	{ AC97_MASTER_MONO, 0x001f },
	{ AC97_PC_BEEP, 0x001f },
	{ AC97_PHONE, 0x001f },
	{ AC97_MIC, 0x001f },
	{ AC97_LINE, 0x1f1f },
	{ AC97_CD, 0x1f1f },
	{ AC97_VIDEO, 0x1f1f },
	{ AC97_AUX, 0x1f1f },
	{ AC97_PCM, 0x1f1f },
	{ AC97_REC_GAIN, 0x0f0f },
	{ } /* terminator */
};

/* initialize the ac97 into a known state */
static void
snd_nm256_ac97_reset(struct snd_ac97 *ac97)
{
	struct nm256 *chip = ac97->private_data;

	/* Reset the mixer.  'Tis magic!  */
	snd_nm256_writeb(chip, 0x6c0, 1);
	if (! chip->reset_workaround) {
		/* Dell latitude LS will lock up by this */
		snd_nm256_writeb(chip, 0x6cc, 0x87);
	}
	if (! chip->reset_workaround_2) {
		/* Dell latitude CSx will lock up by this */
		snd_nm256_writeb(chip, 0x6cc, 0x80);
		snd_nm256_writeb(chip, 0x6cc, 0x0);
	}
	if (! chip->in_resume) {
		int i;
		for (i = 0; i < ARRAY_SIZE(nm256_ac97_init_val); i++) {
			/* preload the cache, so as to avoid even a single
			 * read of the mixer regs
			 */
			snd_nm256_ac97_write(ac97, nm256_ac97_init_val[i].reg,
					     nm256_ac97_init_val[i].value);
		}
	}
}

/* create an ac97 mixer interface */
static int __devinit
snd_nm256_mixer(struct nm256 *chip)
{
	struct snd_ac97_bus *pbus;
	struct snd_ac97_template ac97;
	int err;
	static struct snd_ac97_bus_ops ops = {
		.reset = snd_nm256_ac97_reset,
		.write = snd_nm256_ac97_write,
		.read = snd_nm256_ac97_read,
	};

	chip->ac97_regs = kcalloc(ARRAY_SIZE(nm256_ac97_init_val),
				  sizeof(short), GFP_KERNEL);
	if (! chip->ac97_regs)
		return -ENOMEM;

	if ((err = snd_ac97_bus(chip->card, 0, &ops, NULL, &pbus)) < 0)
		return err;

	memset(&ac97, 0, sizeof(ac97));
	ac97.scaps = AC97_SCAP_AUDIO; /* we support audio! */
	ac97.private_data = chip;
	ac97.res_table = nm256_res_table;
	pbus->no_vra = 1;
	err = snd_ac97_mixer(pbus, &ac97, &chip->ac97);
	if (err < 0)
		return err;
	if (! (chip->ac97->id & (0xf0000000))) {
		/* looks like an invalid id */
		sprintf(chip->card->mixername, "%s AC97", chip->card->driver);
	}
	return 0;
}

/* 
 * See if the signature left by the NM256 BIOS is intact; if so, we use
 * the associated address as the end of our audio buffer in the video
 * RAM.
 */

static int __devinit
snd_nm256_peek_for_sig(struct nm256 *chip)
{
	/* The signature is located 1K below the end of video RAM.  */
	void __iomem *temp;
	/* Default buffer end is 5120 bytes below the top of RAM.  */
	unsigned long pointer_found = chip->buffer_end - 0x1400;
	u32 sig;

	temp = ioremap_nocache(chip->buffer_addr + chip->buffer_end - 0x400, 16);
	if (temp == NULL) {
		snd_printk(KERN_ERR "Unable to scan for card signature in video RAM\n");
		return -EBUSY;
	}

	sig = readl(temp);
	if ((sig & NM_SIG_MASK) == NM_SIGNATURE) {
		u32 pointer = readl(temp + 4);

		/*
		 * If it's obviously invalid, don't use it
		 */
		if (pointer == 0xffffffff ||
		    pointer < chip->buffer_size ||
		    pointer > chip->buffer_end) {
			snd_printk(KERN_ERR "invalid signature found: 0x%x\n", pointer);
			iounmap(temp);
			return -ENODEV;
		} else {
			pointer_found = pointer;
			printk(KERN_INFO "nm256: found card signature in video RAM: 0x%x\n",
			       pointer);
		}
	}

	iounmap(temp);
	chip->buffer_end = pointer_found;

	return 0;
}

#ifdef CONFIG_PM
/*
 * APM event handler, so the card is properly reinitialized after a power
 * event.
 */
static int nm256_suspend(struct pci_dev *pci, pm_message_t state)
{
	struct snd_card *card = pci_get_drvdata(pci);
	struct nm256 *chip = card->private_data;

	snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
	snd_pcm_suspend_all(chip->pcm);
	snd_ac97_suspend(chip->ac97);
	chip->coeffs_current = 0;
	pci_disable_device(pci);
	pci_save_state(pci);
	pci_set_power_state(pci, pci_choose_state(pci, state));
	return 0;
}

static int nm256_resume(struct pci_dev *pci)
{
	struct snd_card *card = pci_get_drvdata(pci);
	struct nm256 *chip = card->private_data;
	int i;

	/* Perform a full reset on the hardware */
	chip->in_resume = 1;

	pci_set_power_state(pci, PCI_D0);
	pci_restore_state(pci);
	if (pci_enable_device(pci) < 0) {
		printk(KERN_ERR "nm256: pci_enable_device failed, "
		       "disabling device\n");
		snd_card_disconnect(card);
		return -EIO;
	}
	pci_set_master(pci);

	snd_nm256_init_chip(chip);

	/* restore ac97 */
	snd_ac97_resume(chip->ac97);

	for (i = 0; i < 2; i++) {
		struct nm256_stream *s = &chip->streams[i];
		if (s->substream && s->suspended) {
			spin_lock_irq(&chip->reg_lock);
			snd_nm256_set_format(chip, s, s->substream);
			spin_unlock_irq(&chip->reg_lock);
		}
	}

	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
	chip->in_resume = 0;
	return 0;
}
#endif /* CONFIG_PM */

static int snd_nm256_free(struct nm256 *chip)
{
	if (chip->streams[SNDRV_PCM_STREAM_PLAYBACK].running)
		snd_nm256_playback_stop(chip);
	if (chip->streams[SNDRV_PCM_STREAM_CAPTURE].running)
		snd_nm256_capture_stop(chip);

	if (chip->irq >= 0)
		free_irq(chip->irq, chip);

	if (chip->cport)
		iounmap(chip->cport);
	if (chip->buffer)
		iounmap(chip->buffer);
	release_and_free_resource(chip->res_cport);
	release_and_free_resource(chip->res_buffer);

	pci_disable_device(chip->pci);
	kfree(chip->ac97_regs);
	kfree(chip);
	return 0;
}

static int snd_nm256_dev_free(struct snd_device *device)
{
	struct nm256 *chip = device->device_data;
	return snd_nm256_free(chip);
}

static int __devinit
snd_nm256_create(struct snd_card *card, struct pci_dev *pci,
		 struct nm256 **chip_ret)
{
	struct nm256 *chip;
	int err, pval;
	static struct snd_device_ops ops = {
		.dev_free =	snd_nm256_dev_free,
	};
	u32 addr;

	*chip_ret = NULL;

	if ((err = pci_enable_device(pci)) < 0)
		return err;

	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
	if (chip == NULL) {
		pci_disable_device(pci);
		return -ENOMEM;
	}

	chip->card = card;
	chip->pci = pci;
	chip->use_cache = use_cache;
	spin_lock_init(&chip->reg_lock);
	chip->irq = -1;
	mutex_init(&chip->irq_mutex);

	/* store buffer sizes in bytes */
	chip->streams[SNDRV_PCM_STREAM_PLAYBACK].bufsize = playback_bufsize * 1024;
	chip->streams[SNDRV_PCM_STREAM_CAPTURE].bufsize = capture_bufsize * 1024;

	/* 
	 * The NM256 has two memory ports.  The first port is nothing
	 * more than a chunk of video RAM, which is used as the I/O ring
	 * buffer.  The second port has the actual juicy stuff (like the
	 * mixer and the playback engine control registers).
	 */

	chip->buffer_addr = pci_resource_start(pci, 0);
	chip->cport_addr = pci_resource_start(pci, 1);

	/* Init the memory port info.  */
	/* remap control port (#2) */
	chip->res_cport = request_mem_region(chip->cport_addr, NM_PORT2_SIZE,
					     card->driver);
	if (chip->res_cport == NULL) {
		snd_printk(KERN_ERR "memory region 0x%lx (size 0x%x) busy\n",
			   chip->cport_addr, NM_PORT2_SIZE);
		err = -EBUSY;
		goto __error;
	}
	chip->cport = ioremap_nocache(chip->cport_addr, NM_PORT2_SIZE);
	if (chip->cport == NULL) {
		snd_printk(KERN_ERR "unable to map control port %lx\n", chip->cport_addr);
		err = -ENOMEM;
		goto __error;
	}

	if (!strcmp(card->driver, "NM256AV")) {
		/* Ok, try to see if this is a non-AC97 version of the hardware. */
		pval = snd_nm256_readw(chip, NM_MIXER_PRESENCE);
		if ((pval & NM_PRESENCE_MASK) != NM_PRESENCE_VALUE) {
			if (! force_ac97) {
				printk(KERN_ERR "nm256: no ac97 is found!\n");
				printk(KERN_ERR "  force the driver to load by "
				       "passing in the module parameter\n");
				printk(KERN_ERR "    force_ac97=1\n");
				printk(KERN_ERR "  or try sb16, opl3sa2, or "
				       "cs423x drivers instead.\n");
				err = -ENXIO;
				goto __error;
			}
		}
		chip->buffer_end = 2560 * 1024;
		chip->interrupt = snd_nm256_interrupt;
		chip->mixer_status_offset = NM_MIXER_STATUS_OFFSET;
		chip->mixer_status_mask = NM_MIXER_READY_MASK;
	} else {
		/* Not sure if there is any relevant detect for the ZX or not.  */
		if (snd_nm256_readb(chip, 0xa0b) != 0)
			chip->buffer_end = 6144 * 1024;
		else
			chip->buffer_end = 4096 * 1024;

		chip->interrupt = snd_nm256_interrupt_zx;
		chip->mixer_status_offset = NM2_MIXER_STATUS_OFFSET;
		chip->mixer_status_mask = NM2_MIXER_READY_MASK;
	}
	
	chip->buffer_size = chip->streams[SNDRV_PCM_STREAM_PLAYBACK].bufsize +
		chip->streams[SNDRV_PCM_STREAM_CAPTURE].bufsize;
	if (chip->use_cache)
		chip->buffer_size += NM_TOTAL_COEFF_COUNT * 4;
	else
		chip->buffer_size += NM_MAX_PLAYBACK_COEF_SIZE + NM_MAX_RECORD_COEF_SIZE;

	if (buffer_top >= chip->buffer_size && buffer_top < chip->buffer_end)
		chip->buffer_end = buffer_top;
	else {
		/* get buffer end pointer from signature */
		if ((err = snd_nm256_peek_for_sig(chip)) < 0)
			goto __error;
	}

	chip->buffer_start = chip->buffer_end - chip->buffer_size;
	chip->buffer_addr += chip->buffer_start;

	printk(KERN_INFO "nm256: Mapping port 1 from 0x%x - 0x%x\n",
	       chip->buffer_start, chip->buffer_end);

	chip->res_buffer = request_mem_region(chip->buffer_addr,
					      chip->buffer_size,
					      card->driver);
	if (chip->res_buffer == NULL) {
		snd_printk(KERN_ERR "nm256: buffer 0x%lx (size 0x%x) busy\n",
			   chip->buffer_addr, chip->buffer_size);
		err = -EBUSY;
		goto __error;
	}
	chip->buffer = ioremap_nocache(chip->buffer_addr, chip->buffer_size);
	if (chip->buffer == NULL) {
		err = -ENOMEM;
		snd_printk(KERN_ERR "unable to map ring buffer at %lx\n", chip->buffer_addr);
		goto __error;
	}

	/* set offsets */
	addr = chip->buffer_start;
	chip->streams[SNDRV_PCM_STREAM_PLAYBACK].buf = addr;
	addr += chip->streams[SNDRV_PCM_STREAM_PLAYBACK].bufsize;
	chip->streams[SNDRV_PCM_STREAM_CAPTURE].buf = addr;
	addr += chip->streams[SNDRV_PCM_STREAM_CAPTURE].bufsize;
	if (chip->use_cache) {
		chip->all_coeff_buf = addr;
	} else {
		chip->coeff_buf[SNDRV_PCM_STREAM_PLAYBACK] = addr;
		addr += NM_MAX_PLAYBACK_COEF_SIZE;
		chip->coeff_buf[SNDRV_PCM_STREAM_CAPTURE] = addr;
	}

	/* Fixed setting. */
	chip->mixer_base = NM_MIXER_OFFSET;

	chip->coeffs_current = 0;

	snd_nm256_init_chip(chip);

	// pci_set_master(pci); /* needed? */
	
	if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0)
		goto __error;

	snd_card_set_dev(card, &pci->dev);

	*chip_ret = chip;
	return 0;

__error:
	snd_nm256_free(chip);
	return err;
}


enum { NM_BLACKLISTED, NM_RESET_WORKAROUND, NM_RESET_WORKAROUND_2 };

static struct snd_pci_quirk nm256_quirks[] __devinitdata = {
	/* HP omnibook 4150 has cs4232 codec internally */
	SND_PCI_QUIRK(0x103c, 0x0007, "HP omnibook 4150", NM_BLACKLISTED),
	/* Reset workarounds to avoid lock-ups */
	SND_PCI_QUIRK(0x104d, 0x8041, "Sony PCG-F305", NM_RESET_WORKAROUND),
	SND_PCI_QUIRK(0x1028, 0x0080, "Dell Latitude LS", NM_RESET_WORKAROUND),
	SND_PCI_QUIRK(0x1028, 0x0091, "Dell Latitude CSx", NM_RESET_WORKAROUND_2),
	{ } /* terminator */
};


static int __devinit snd_nm256_probe(struct pci_dev *pci,
				     const struct pci_device_id *pci_id)
{
	struct snd_card *card;
	struct nm256 *chip;
	int err;
	const struct snd_pci_quirk *q;

	q = snd_pci_quirk_lookup(pci, nm256_quirks);
	if (q) {
		snd_printdd(KERN_INFO "nm256: Enabled quirk for %s.\n", q->name);
		switch (q->value) {
		case NM_BLACKLISTED:
			printk(KERN_INFO "nm256: The device is blacklisted. "
			       "Loading stopped\n");
			return -ENODEV;
		case NM_RESET_WORKAROUND_2:
			reset_workaround_2 = 1;
			/* Fall-through */
		case NM_RESET_WORKAROUND:
			reset_workaround = 1;
			break;
		}
	}

	err = snd_card_create(index, id, THIS_MODULE, 0, &card);
	if (err < 0)
		return err;

	switch (pci->device) {
	case PCI_DEVICE_ID_NEOMAGIC_NM256AV_AUDIO:
		strcpy(card->driver, "NM256AV");
		break;
	case PCI_DEVICE_ID_NEOMAGIC_NM256ZX_AUDIO:
		strcpy(card->driver, "NM256ZX");
		break;
	case PCI_DEVICE_ID_NEOMAGIC_NM256XL_PLUS_AUDIO:
		strcpy(card->driver, "NM256XL+");
		break;
	default:
		snd_printk(KERN_ERR "invalid device id 0x%x\n", pci->device);
		snd_card_free(card);
		return -EINVAL;
	}

	if (vaio_hack)
		buffer_top = 0x25a800;	/* this avoids conflicts with XFree86 server */

	if (playback_bufsize < 4)
		playback_bufsize = 4;
	if (playback_bufsize > 128)
		playback_bufsize = 128;
	if (capture_bufsize < 4)
		capture_bufsize = 4;
	if (capture_bufsize > 128)
		capture_bufsize = 128;
	if ((err = snd_nm256_create(card, pci, &chip)) < 0) {
		snd_card_free(card);
		return err;
	}
	card->private_data = chip;

	if (reset_workaround) {
		snd_printdd(KERN_INFO "nm256: reset_workaround activated\n");
		chip->reset_workaround = 1;
	}

	if (reset_workaround_2) {
		snd_printdd(KERN_INFO "nm256: reset_workaround_2 activated\n");
		chip->reset_workaround_2 = 1;
	}

	if ((err = snd_nm256_pcm(chip, 0)) < 0 ||
	    (err = snd_nm256_mixer(chip)) < 0) {
		snd_card_free(card);
		return err;
	}

	sprintf(card->shortname, "NeoMagic %s", card->driver);
	sprintf(card->longname, "%s at 0x%lx & 0x%lx, irq %d",
		card->shortname,
		chip->buffer_addr, chip->cport_addr, chip->irq);

	if ((err = snd_card_register(card)) < 0) {
		snd_card_free(card);
		return err;
	}

	pci_set_drvdata(pci, card);
	return 0;
}

static void __devexit snd_nm256_remove(struct pci_dev *pci)
{
	snd_card_free(pci_get_drvdata(pci));
	pci_set_drvdata(pci, NULL);
}


static struct pci_driver driver = {
	.name = KBUILD_MODNAME,
	.id_table = snd_nm256_ids,
	.probe = snd_nm256_probe,
	.remove = __devexit_p(snd_nm256_remove),
#ifdef CONFIG_PM
	.suspend = nm256_suspend,
	.resume = nm256_resume,
#endif
};


static int __init alsa_card_nm256_init(void)
{
	return pci_register_driver(&driver);
}

static void __exit alsa_card_nm256_exit(void)
{
	pci_unregister_driver(&driver);
}

module_init(alsa_card_nm256_init)
module_exit(alsa_card_nm256_exit)