aboutsummaryrefslogblamecommitdiffstats
path: root/sound/oss/nec_vrc5477.c
blob: 21c1954d91080a086fb961d946d3d97b29577738 (plain) (tree)
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















































































                                                                             

                        























































































































                                                                            
                                











































































































































































































































                                                                            
                  




















































































































                                                                            
                                                         

































































































                                                                           
                                                               



































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































                                                                                               
                                   


                                                 
                                                     



                                                        
                                             




                                                        
                                           

























                                                                  
                                     










                                                                       
                                   








                                                                   
                                     
























































































































































































                                                                               
                                   
















































































































































































                                                                                                
                                                         










                                                    
/***********************************************************************
 * Copyright 2001 MontaVista Software Inc.
 * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
 *
 * drivers/sound/nec_vrc5477.c
 *     AC97 sound dirver for NEC Vrc5477 chip (an integrated, 
 *     multi-function controller chip for MIPS CPUs)
 *
 * VRA support Copyright 2001 Bradley D. LaRonde <brad@ltc.com>
 *
 * 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 code is derived from ite8172.c, which is written by Steve Longerbeam.
 *
 * Features:
 *   Currently we only support the following capabilities:
 *	. mono output to PCM L/R (line out).
 *	. stereo output to PCM L/R (line out).
 *	. mono input from PCM L (line in).
 *	. stereo output from PCM (line in).
 *	. sampling rate at 48k or variable sampling rate 
 *	. support /dev/dsp, /dev/mixer devices, standard OSS devices.
 *	. only support 16-bit PCM format (hardware limit, no software
 *	  translation) 
 *	. support duplex, but no trigger or realtime.
 *	
 *   Specifically the following are not supported:
 *	. app-set frag size.
 *	. mmap'ed buffer access
 */

/* 
 * Original comments from ite8172.c file.
 */

/*
 *
 * Notes:
 *
 *  1. Much of the OSS buffer allocation, ioctl's, and mmap'ing are
 *     taken, slightly modified or not at all, from the ES1371 driver,
 *     so refer to the credits in es1371.c for those. The rest of the
 *     code (probe, open, read, write, the ISR, etc.) is new.
 *  2. The following support is untested:
 *      * Memory mapping the audio buffers, and the ioctl controls that go
 *        with it.
 *      * S/PDIF output.
 *  3. The following is not supported:
 *      * I2S input.
 *      * legacy audio mode.
 *  4. Support for volume button interrupts is implemented but doesn't
 *     work yet.
 *
 *  Revision history
 *    02.08.2001  0.1   Initial release
 */

#include <linux/module.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/ioport.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/sound.h>
#include <linux/slab.h>
#include <linux/soundcard.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/bitops.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/smp_lock.h>
#include <linux/ac97_codec.h>
#include <linux/mutex.h>

#include <asm/io.h>
#include <asm/dma.h>
#include <asm/uaccess.h>

/* -------------------debug macros -------------------------------------- */
/* #undef VRC5477_AC97_DEBUG */
#define VRC5477_AC97_DEBUG

#undef VRC5477_AC97_VERBOSE_DEBUG
/* #define VRC5477_AC97_VERBOSE_DEBUG */

#if defined(VRC5477_AC97_VERBOSE_DEBUG)
#define VRC5477_AC97_DEBUG
#endif

#if defined(VRC5477_AC97_DEBUG)
#define ASSERT(x)  if (!(x)) { \
	panic("assertion failed at %s:%d: %s\n", __FILE__, __LINE__, #x); }
#else
#define	ASSERT(x)
#endif /* VRC5477_AC97_DEBUG */

#if defined(VRC5477_AC97_VERBOSE_DEBUG)
static u16 inTicket; 		/* check sync between intr & write */
static u16 outTicket;
#endif

/* --------------------------------------------------------------------- */

#undef OSS_DOCUMENTED_MIXER_SEMANTICS

static const unsigned sample_shift[] = { 0, 1, 1, 2 };

#define         VRC5477_INT_CLR         0x0
#define         VRC5477_INT_STATUS	0x0
#define         VRC5477_CODEC_WR        0x4
#define         VRC5477_CODEC_RD        0x8
#define         VRC5477_CTRL            0x18
#define         VRC5477_ACLINK_CTRL     0x1c
#define         VRC5477_INT_MASK        0x24

#define		VRC5477_DAC1_CTRL	0x30
#define		VRC5477_DAC1L		0x34
#define		VRC5477_DAC1_BADDR	0x38
#define		VRC5477_DAC2_CTRL	0x3c
#define		VRC5477_DAC2L		0x40
#define		VRC5477_DAC2_BADDR	0x44
#define		VRC5477_DAC3_CTRL	0x48
#define		VRC5477_DAC3L		0x4c
#define		VRC5477_DAC3_BADDR	0x50

#define		VRC5477_ADC1_CTRL	0x54
#define		VRC5477_ADC1L		0x58
#define		VRC5477_ADC1_BADDR	0x5c
#define		VRC5477_ADC2_CTRL	0x60
#define		VRC5477_ADC2L		0x64
#define		VRC5477_ADC2_BADDR	0x68
#define		VRC5477_ADC3_CTRL	0x6c
#define		VRC5477_ADC3L		0x70
#define		VRC5477_ADC3_BADDR	0x74

#define		VRC5477_CODEC_WR_RWC	(1 << 23)

#define		VRC5477_CODEC_RD_RRDYA	(1 << 31)
#define		VRC5477_CODEC_RD_RRDYD	(1 << 30)

#define		VRC5477_ACLINK_CTRL_RST_ON	(1 << 15)
#define		VRC5477_ACLINK_CTRL_RST_TIME	0x7f
#define		VRC5477_ACLINK_CTRL_SYNC_ON	(1 << 30)
#define		VRC5477_ACLINK_CTRL_CK_STOP_ON	(1 << 31)

#define		VRC5477_CTRL_DAC2ENB		(1 << 15) 
#define		VRC5477_CTRL_ADC2ENB		(1 << 14) 
#define		VRC5477_CTRL_DAC1ENB		(1 << 13) 
#define		VRC5477_CTRL_ADC1ENB		(1 << 12) 

#define		VRC5477_INT_MASK_NMASK		(1 << 31) 
#define		VRC5477_INT_MASK_DAC1END	(1 << 5) 
#define		VRC5477_INT_MASK_DAC2END	(1 << 4) 
#define		VRC5477_INT_MASK_DAC3END	(1 << 3) 
#define		VRC5477_INT_MASK_ADC1END	(1 << 2) 
#define		VRC5477_INT_MASK_ADC2END	(1 << 1) 
#define		VRC5477_INT_MASK_ADC3END	(1 << 0) 

#define		VRC5477_DMA_ACTIVATION		(1 << 31)
#define		VRC5477_DMA_WIP			(1 << 30)


#define VRC5477_AC97_MODULE_NAME "NEC_Vrc5477_audio"
#define PFX VRC5477_AC97_MODULE_NAME ": "

/* --------------------------------------------------------------------- */

struct vrc5477_ac97_state {
	/* list of vrc5477_ac97 devices */
	struct list_head devs;

	/* the corresponding pci_dev structure */
	struct pci_dev *dev;

	/* soundcore stuff */
	int dev_audio;

	/* hardware resources */
	unsigned long io;
	unsigned int irq;

#ifdef VRC5477_AC97_DEBUG
	/* debug /proc entry */
	struct proc_dir_entry *ps;
	struct proc_dir_entry *ac97_ps;
#endif /* VRC5477_AC97_DEBUG */

	struct ac97_codec *codec;

	unsigned dacChannels, adcChannels;
	unsigned short dacRate, adcRate;
	unsigned short extended_status;

	spinlock_t lock;
	struct mutex open_mutex;
	mode_t open_mode;
	wait_queue_head_t open_wait;

	struct dmabuf {
		void *lbuf, *rbuf;
		dma_addr_t lbufDma, rbufDma;
		unsigned bufOrder;
		unsigned numFrag;
		unsigned fragShift;
		unsigned fragSize;	/* redundant */
		unsigned fragTotalSize;	/* = numFrag * fragSize(real)  */
		unsigned nextIn;
		unsigned nextOut;
		int count;
		unsigned error; /* over/underrun */
		wait_queue_head_t wait;
		/* OSS stuff */
		unsigned stopped:1;
		unsigned ready:1;
	} dma_dac, dma_adc;

	#define	WORK_BUF_SIZE	2048
	struct {
		u16 lchannel;
		u16 rchannel;
	} workBuf[WORK_BUF_SIZE/4];
};

/* --------------------------------------------------------------------- */

static LIST_HEAD(devs);

/* --------------------------------------------------------------------- */

static inline unsigned ld2(unsigned int x)
{
    unsigned r = 0;
	
    if (x >= 0x10000) {
	x >>= 16;
	r += 16;
    }
    if (x >= 0x100) {
	x >>= 8;
	r += 8;
    }
    if (x >= 0x10) {
	x >>= 4;
	r += 4;
    }
    if (x >= 4) {
	x >>= 2;
	r += 2;
    }
    if (x >= 2)
	r++;
    return r;
}

/* --------------------------------------------------------------------- */

static u16 rdcodec(struct ac97_codec *codec, u8 addr)
{
	struct vrc5477_ac97_state *s = 
		(struct vrc5477_ac97_state *)codec->private_data;
	unsigned long flags;
	u32 result;

	spin_lock_irqsave(&s->lock, flags);

	/* wait until we can access codec registers */
	while (inl(s->io + VRC5477_CODEC_WR) & 0x80000000);

	/* write the address and "read" command to codec */
	addr = addr & 0x7f;
	outl((addr << 16) | VRC5477_CODEC_WR_RWC, s->io + VRC5477_CODEC_WR);

	/* get the return result */
	udelay(100); /* workaround hardware bug */
	while ( (result = inl(s->io + VRC5477_CODEC_RD)) & 
                (VRC5477_CODEC_RD_RRDYA | VRC5477_CODEC_RD_RRDYD) ) {
		/* we get either addr or data, or both */
		if (result & VRC5477_CODEC_RD_RRDYA) {
			ASSERT(addr == ((result >> 16) & 0x7f) );
		}
		if (result & VRC5477_CODEC_RD_RRDYD) {
			break;
		}
	}

	spin_unlock_irqrestore(&s->lock, flags);

	return result & 0xffff;
}


static void wrcodec(struct ac97_codec *codec, u8 addr, u16 data)
{
	struct vrc5477_ac97_state *s = 
		(struct vrc5477_ac97_state *)codec->private_data;
	unsigned long flags;

	spin_lock_irqsave(&s->lock, flags);

	/* wait until we can access codec registers */
	while (inl(s->io + VRC5477_CODEC_WR) & 0x80000000);

	/* write the address and value to codec */
	outl((addr << 16) | data, s->io + VRC5477_CODEC_WR);

	spin_unlock_irqrestore(&s->lock, flags);
}


static void waitcodec(struct ac97_codec *codec)
{
	struct vrc5477_ac97_state *s = 
		(struct vrc5477_ac97_state *)codec->private_data;

	/* wait until we can access codec registers */
	while (inl(s->io + VRC5477_CODEC_WR) & 0x80000000);
}

static int ac97_codec_not_present(struct ac97_codec *codec)
{
	struct vrc5477_ac97_state *s = 
		(struct vrc5477_ac97_state *)codec->private_data;
	unsigned long flags;
	unsigned short count  = 0xffff; 

	spin_lock_irqsave(&s->lock, flags);

	/* wait until we can access codec registers */
	do {
	       if (!(inl(s->io + VRC5477_CODEC_WR) & 0x80000000))
		       break;
	} while (--count);

	if (count == 0) {
		spin_unlock_irqrestore(&s->lock, flags);
		return -1;
	}

	/* write 0 to reset */
	outl((AC97_RESET << 16) | 0, s->io + VRC5477_CODEC_WR);

	/* test whether we get a response from ac97 chip */
	count  = 0xffff; 
	do { 
	       if (!(inl(s->io + VRC5477_CODEC_WR) & 0x80000000))
		       break;
	} while (--count);

	if (count == 0) {
		spin_unlock_irqrestore(&s->lock, flags);
		return -1;
	}
	spin_unlock_irqrestore(&s->lock, flags);
	return 0;
}

/* --------------------------------------------------------------------- */

static void vrc5477_ac97_delay(int msec)
{
	unsigned long tmo;
	signed long tmo2;

	if (in_interrupt())
		return;
    
	tmo = jiffies + (msec*HZ)/1000;
	for (;;) {
		tmo2 = tmo - jiffies;
		if (tmo2 <= 0)
			break;
		schedule_timeout(tmo2);
	}
}


static void set_adc_rate(struct vrc5477_ac97_state *s, unsigned rate)
{
	wrcodec(s->codec, AC97_PCM_LR_ADC_RATE, rate);
	s->adcRate = rate;
}


static void set_dac_rate(struct vrc5477_ac97_state *s, unsigned rate)
{
	if(s->extended_status & AC97_EXTSTAT_VRA) {
	wrcodec(s->codec, AC97_PCM_FRONT_DAC_RATE, rate);
		s->dacRate = rdcodec(s->codec, AC97_PCM_FRONT_DAC_RATE);
	}
}

static int ac97_codec_not_present(struct ac97_codec *codec)
{
	struct vrc5477_ac97_state *s =
		(struct vrc5477_ac97_state *)codec->private_data;
	unsigned long flags;
	unsigned short count  = 0xffff;

	spin_lock_irqsave(&s->lock, flags);

	/* wait until we can access codec registers */
	do {
	       if (!(inl(s->io + VRC5477_CODEC_WR) & 0x80000000))
		       break;
	} while (--count);

	if (count == 0) {
		spin_unlock_irqrestore(&s->lock, flags);
		return -1;
	}

	/* write 0 to reset */
	outl((AC97_RESET << 16) | 0, s->io + VRC5477_CODEC_WR);

	/* test whether we get a response from ac97 chip */
	count  = 0xffff;
	do {
	       if (!(inl(s->io + VRC5477_CODEC_WR) & 0x80000000))
		       break;
	} while (--count);

	if (count == 0) {
		spin_unlock_irqrestore(&s->lock, flags);
		return -1;
	}
	spin_unlock_irqrestore(&s->lock, flags);
	return 0;
}

/* --------------------------------------------------------------------- */

static inline void
stop_dac(struct vrc5477_ac97_state *s)
{
	struct dmabuf* db = &s->dma_dac;
	unsigned long flags;
	u32 temp;
    
	spin_lock_irqsave(&s->lock, flags);

	if (db->stopped) {
		spin_unlock_irqrestore(&s->lock, flags);
		return;
	}

	/* deactivate the dma */
	outl(0, s->io + VRC5477_DAC1_CTRL);
	outl(0, s->io + VRC5477_DAC2_CTRL);

	/* wait for DAM completely stop */
	while (inl(s->io + VRC5477_DAC1_CTRL) & VRC5477_DMA_WIP);
	while (inl(s->io + VRC5477_DAC2_CTRL) & VRC5477_DMA_WIP);

	/* disable dac slots in aclink */
	temp = inl(s->io + VRC5477_CTRL);
	temp &= ~ (VRC5477_CTRL_DAC1ENB | VRC5477_CTRL_DAC2ENB);
	outl (temp, s->io + VRC5477_CTRL);

	/* disable interrupts */
	temp = inl(s->io + VRC5477_INT_MASK);
	temp &= ~ (VRC5477_INT_MASK_DAC1END | VRC5477_INT_MASK_DAC2END); 
	outl (temp, s->io + VRC5477_INT_MASK);

	/* clear pending ones */
	outl(VRC5477_INT_MASK_DAC1END | VRC5477_INT_MASK_DAC2END, 
	     s->io +  VRC5477_INT_CLR);
    
	db->stopped = 1;
    
	spin_unlock_irqrestore(&s->lock, flags);
}	

static void start_dac(struct vrc5477_ac97_state *s)
{
	struct dmabuf* db = &s->dma_dac;
	unsigned long flags;
	u32 dmaLength;
	u32 temp;

	spin_lock_irqsave(&s->lock, flags);

	if (!db->stopped) {
		spin_unlock_irqrestore(&s->lock, flags);
		return;
	}

	/* we should have some data to do the DMA trasnfer */
	ASSERT(db->count >= db->fragSize);

	/* clear pending fales interrupts */
	outl(VRC5477_INT_MASK_DAC1END | VRC5477_INT_MASK_DAC2END, 
	     s->io +  VRC5477_INT_CLR);

	/* enable interrupts */
	temp = inl(s->io + VRC5477_INT_MASK);
	temp |= VRC5477_INT_MASK_DAC1END | VRC5477_INT_MASK_DAC2END;
	outl(temp, s->io +  VRC5477_INT_MASK);

	/* setup dma base addr */
	outl(db->lbufDma + db->nextOut, s->io + VRC5477_DAC1_BADDR);
	if (s->dacChannels == 1) {
		outl(db->lbufDma + db->nextOut, s->io + VRC5477_DAC2_BADDR);
	} else {
		outl(db->rbufDma + db->nextOut, s->io + VRC5477_DAC2_BADDR);
	}

	/* set dma length, in the unit of 0x10 bytes */
	dmaLength = db->fragSize >> 4;
	outl(dmaLength, s->io + VRC5477_DAC1L);
	outl(dmaLength, s->io + VRC5477_DAC2L);

	/* activate dma */
	outl(VRC5477_DMA_ACTIVATION, s->io + VRC5477_DAC1_CTRL);
	outl(VRC5477_DMA_ACTIVATION, s->io + VRC5477_DAC2_CTRL);

	/* enable dac slots - we should hear the music now! */
	temp = inl(s->io + VRC5477_CTRL);
	temp |= (VRC5477_CTRL_DAC1ENB | VRC5477_CTRL_DAC2ENB);
	outl (temp, s->io + VRC5477_CTRL);

	/* it is time to setup next dma transfer */
	ASSERT(inl(s->io + VRC5477_DAC1_CTRL) & VRC5477_DMA_WIP);
	ASSERT(inl(s->io + VRC5477_DAC2_CTRL) & VRC5477_DMA_WIP);

	temp = db->nextOut + db->fragSize;
	if (temp >= db->fragTotalSize) {
		ASSERT(temp == db->fragTotalSize);
		temp = 0;
	}

	outl(db->lbufDma + temp, s->io + VRC5477_DAC1_BADDR);
	if (s->dacChannels == 1) {
		outl(db->lbufDma + temp, s->io + VRC5477_DAC2_BADDR);
	} else {
		outl(db->rbufDma + temp, s->io + VRC5477_DAC2_BADDR);
	}

	db->stopped = 0;

#if defined(VRC5477_AC97_VERBOSE_DEBUG)
	outTicket = *(u16*)(db->lbuf+db->nextOut);
	if (db->count > db->fragSize) {
		ASSERT((u16)(outTicket+1) == *(u16*)(db->lbuf+temp));
	}
#endif

	spin_unlock_irqrestore(&s->lock, flags);
}	

static inline void stop_adc(struct vrc5477_ac97_state *s)
{
	struct dmabuf* db = &s->dma_adc;
	unsigned long flags;
	u32 temp;
    
	spin_lock_irqsave(&s->lock, flags);

	if (db->stopped) {
		spin_unlock_irqrestore(&s->lock, flags);
		return;
	}

	/* deactivate the dma */
	outl(0, s->io + VRC5477_ADC1_CTRL);
	outl(0, s->io + VRC5477_ADC2_CTRL);

	/* disable adc slots in aclink */
	temp = inl(s->io + VRC5477_CTRL);
	temp &= ~ (VRC5477_CTRL_ADC1ENB | VRC5477_CTRL_ADC2ENB);
	outl (temp, s->io + VRC5477_CTRL);

	/* disable interrupts */
        temp = inl(s->io + VRC5477_INT_MASK);
        temp &= ~ (VRC5477_INT_MASK_ADC1END | VRC5477_INT_MASK_ADC2END); 
        outl (temp, s->io + VRC5477_INT_MASK);

	/* clear pending ones */
	outl(VRC5477_INT_MASK_ADC1END | VRC5477_INT_MASK_ADC2END, 
	     s->io +  VRC5477_INT_CLR);
    
	db->stopped = 1;

	spin_unlock_irqrestore(&s->lock, flags);
}	

static void start_adc(struct vrc5477_ac97_state *s)
{
	struct dmabuf* db = &s->dma_adc;
	unsigned long flags;
	u32 dmaLength;
	u32 temp;

	spin_lock_irqsave(&s->lock, flags);

	if (!db->stopped) {
		spin_unlock_irqrestore(&s->lock, flags);
		return;
	}

	/* we should at least have some free space in the buffer */
	ASSERT(db->count < db->fragTotalSize - db->fragSize * 2);

	/* clear pending ones */
	outl(VRC5477_INT_MASK_ADC1END | VRC5477_INT_MASK_ADC2END, 
	     s->io +  VRC5477_INT_CLR);

        /* enable interrupts */
        temp = inl(s->io + VRC5477_INT_MASK);
        temp |= VRC5477_INT_MASK_ADC1END | VRC5477_INT_MASK_ADC2END;
        outl(temp, s->io +  VRC5477_INT_MASK);

	/* setup dma base addr */
	outl(db->lbufDma + db->nextIn, s->io + VRC5477_ADC1_BADDR);
	outl(db->rbufDma + db->nextIn, s->io + VRC5477_ADC2_BADDR);

	/* setup dma length */
	dmaLength = db->fragSize >> 4;
	outl(dmaLength, s->io + VRC5477_ADC1L);
	outl(dmaLength, s->io + VRC5477_ADC2L);

	/* activate dma */
	outl(VRC5477_DMA_ACTIVATION, s->io + VRC5477_ADC1_CTRL);
	outl(VRC5477_DMA_ACTIVATION, s->io + VRC5477_ADC2_CTRL);

	/* enable adc slots */
	temp = inl(s->io + VRC5477_CTRL);
	temp |= (VRC5477_CTRL_ADC1ENB | VRC5477_CTRL_ADC2ENB);
	outl (temp, s->io + VRC5477_CTRL);

	/* it is time to setup next dma transfer */
	temp = db->nextIn + db->fragSize;
	if (temp >= db->fragTotalSize) {
		ASSERT(temp == db->fragTotalSize);
		temp = 0;
	}
	outl(db->lbufDma + temp, s->io + VRC5477_ADC1_BADDR);
	outl(db->rbufDma + temp, s->io + VRC5477_ADC2_BADDR);

	db->stopped = 0;

	spin_unlock_irqrestore(&s->lock, flags);
}	

/* --------------------------------------------------------------------- */

#define DMABUF_DEFAULTORDER (16-PAGE_SHIFT)
#define DMABUF_MINORDER 1

static inline void dealloc_dmabuf(struct vrc5477_ac97_state *s,
				  struct dmabuf *db)
{
	if (db->lbuf) {
		ASSERT(db->rbuf);
		pci_free_consistent(s->dev, PAGE_SIZE << db->bufOrder,
				    db->lbuf, db->lbufDma);
		pci_free_consistent(s->dev, PAGE_SIZE << db->bufOrder,
				    db->rbuf, db->rbufDma);
		db->lbuf = db->rbuf = NULL;
	}
	db->nextIn = db->nextOut = 0;
	db->ready = 0;
}

static int prog_dmabuf(struct vrc5477_ac97_state *s, 
		       struct dmabuf *db,
		       unsigned rate)
{
	int order;
	unsigned bufsize;

	if (!db->lbuf) {
		ASSERT(!db->rbuf);

		db->ready = 0;
		for (order = DMABUF_DEFAULTORDER; 
		     order >= DMABUF_MINORDER; 
		     order--) {
			db->lbuf = pci_alloc_consistent(s->dev,
							PAGE_SIZE << order,
							&db->lbufDma);
			db->rbuf = pci_alloc_consistent(s->dev,
							PAGE_SIZE << order,
							&db->rbufDma);
			if (db->lbuf && db->rbuf) break;
			if (db->lbuf) {
			    ASSERT(!db->rbuf);
			    pci_free_consistent(s->dev, 
						PAGE_SIZE << order,
						db->lbuf,
						db->lbufDma);
			}
		}
		if (!db->lbuf) {
			ASSERT(!db->rbuf);
			return -ENOMEM;
		}

		db->bufOrder = order;
	}

	db->count = 0;
	db->nextIn = db->nextOut = 0;
    
	bufsize = PAGE_SIZE << db->bufOrder;
	db->fragShift = ld2(rate * 2 / 100);
	if (db->fragShift < 4) db->fragShift = 4;

	db->numFrag = bufsize >> db->fragShift;
	while (db->numFrag < 4 && db->fragShift > 4) {
		db->fragShift--;
		db->numFrag = bufsize >> db->fragShift;
	}
	db->fragSize = 1 << db->fragShift;
	db->fragTotalSize = db->numFrag << db->fragShift;
	memset(db->lbuf, 0, db->fragTotalSize);
	memset(db->rbuf, 0, db->fragTotalSize);
    
	db->ready = 1;

	return 0;
}

static inline int prog_dmabuf_adc(struct vrc5477_ac97_state *s)
{
    stop_adc(s);
    return prog_dmabuf(s, &s->dma_adc, s->adcRate);
}

static inline int prog_dmabuf_dac(struct vrc5477_ac97_state *s)
{
    stop_dac(s);
    return prog_dmabuf(s, &s->dma_dac, s->dacRate);
}


/* --------------------------------------------------------------------- */
/* hold spinlock for the following! */

static inline void vrc5477_ac97_adc_interrupt(struct vrc5477_ac97_state *s)
{
	struct dmabuf* adc = &s->dma_adc;
	unsigned temp;

	/* we need two frags avaiable because one is already being used
	 * and the other will be used when next interrupt happens.
	 */
	if (adc->count >= adc->fragTotalSize - adc->fragSize) {
		stop_adc(s);
		adc->error++;
		printk(KERN_INFO PFX "adc overrun\n");
		return;
	}

	/* set the base addr for next DMA transfer */
	temp = adc->nextIn + 2*adc->fragSize;
	if (temp >= adc->fragTotalSize) {
		ASSERT( (temp == adc->fragTotalSize) ||
                             (temp == adc->fragTotalSize + adc->fragSize) );
		temp -= adc->fragTotalSize;
	}
	outl(adc->lbufDma + temp, s->io + VRC5477_ADC1_BADDR);
	outl(adc->rbufDma + temp, s->io + VRC5477_ADC2_BADDR);

	/* adjust nextIn */
	adc->nextIn += adc->fragSize;
	if (adc->nextIn >= adc->fragTotalSize) {
		ASSERT(adc->nextIn == adc->fragTotalSize);
		adc->nextIn = 0;
	}

	/* adjust count */
	adc->count += adc->fragSize;

	/* wake up anybody listening */
	if (waitqueue_active(&adc->wait)) {
		wake_up_interruptible(&adc->wait);
	}	
}

static inline void vrc5477_ac97_dac_interrupt(struct vrc5477_ac97_state *s)
{
	struct dmabuf* dac = &s->dma_dac;
	unsigned temp;

	/* next DMA transfer should already started */
	// ASSERT(inl(s->io + VRC5477_DAC1_CTRL) & VRC5477_DMA_WIP);
	// ASSERT(inl(s->io + VRC5477_DAC2_CTRL) & VRC5477_DMA_WIP);

	/* let us set for next next DMA transfer */
	temp = dac->nextOut + dac->fragSize*2;
	if (temp >= dac->fragTotalSize) {
		ASSERT( (temp == dac->fragTotalSize) || 
                             (temp == dac->fragTotalSize + dac->fragSize) );
		temp -= dac->fragTotalSize;
	}
	outl(dac->lbufDma + temp, s->io + VRC5477_DAC1_BADDR);
	if (s->dacChannels == 1) {
		outl(dac->lbufDma + temp, s->io + VRC5477_DAC2_BADDR);
	} else {
		outl(dac->rbufDma + temp, s->io + VRC5477_DAC2_BADDR);
	}

#if defined(VRC5477_AC97_VERBOSE_DEBUG)
	if (*(u16*)(dac->lbuf +  dac->nextOut) != outTicket) {
		printk("assert fail: - %d vs %d\n", 
		        *(u16*)(dac->lbuf +  dac->nextOut),
                        outTicket);
                ASSERT(1 == 0);
	}
#endif

	/* adjust nextOut pointer */
	dac->nextOut += dac->fragSize;
	if (dac->nextOut >= dac->fragTotalSize) {
		ASSERT(dac->nextOut == dac->fragTotalSize);
		dac->nextOut = 0;
	}

	/* adjust count */
	dac->count -= dac->fragSize;
	if (dac->count <=0 ) {
		/* buffer under run */
		dac->count = 0;
		dac->nextIn = dac->nextOut;
		stop_dac(s);
	}

#if defined(VRC5477_AC97_VERBOSE_DEBUG)
	if (dac->count) {
		outTicket ++;
		ASSERT(*(u16*)(dac->lbuf +  dac->nextOut) == outTicket);
	}
#endif
	
	/* we cannot have both under run and someone is waiting on us */
	ASSERT(! (waitqueue_active(&dac->wait) && (dac->count <= 0)) );

	/* wake up anybody listening */
	if (waitqueue_active(&dac->wait))
		wake_up_interruptible(&dac->wait);
}

static irqreturn_t vrc5477_ac97_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	struct vrc5477_ac97_state *s = (struct vrc5477_ac97_state *)dev_id;
	u32 irqStatus;
	u32 adcInterrupts, dacInterrupts;

	spin_lock(&s->lock);

	/* get irqStatus and clear the detected ones */
	irqStatus = inl(s->io + VRC5477_INT_STATUS);
	outl(irqStatus, s->io + VRC5477_INT_CLR);

	/* let us see what we get */
	dacInterrupts = VRC5477_INT_MASK_DAC1END | VRC5477_INT_MASK_DAC2END;
	adcInterrupts = VRC5477_INT_MASK_ADC1END | VRC5477_INT_MASK_ADC2END;
	if (irqStatus & dacInterrupts) {
		/* we should get both interrupts, but just in case ...  */
		if (irqStatus & VRC5477_INT_MASK_DAC1END) {
			vrc5477_ac97_dac_interrupt(s);
		}
		if ( (irqStatus & dacInterrupts) != dacInterrupts ) {
			printk(KERN_WARNING "vrc5477_ac97 : dac interrupts not in sync!!!\n");
			stop_dac(s);
			start_dac(s);
		}
	} else if (irqStatus & adcInterrupts) {
		/* we should get both interrupts, but just in case ...  */
		if(irqStatus & VRC5477_INT_MASK_ADC1END) {
			vrc5477_ac97_adc_interrupt(s);
		} 
		if ( (irqStatus & adcInterrupts) != adcInterrupts ) {
			printk(KERN_WARNING "vrc5477_ac97 : adc interrupts not in sync!!!\n");
			stop_adc(s);
			start_adc(s);
		}
	}

	spin_unlock(&s->lock);
	return IRQ_HANDLED;
}

/* --------------------------------------------------------------------- */

static int vrc5477_ac97_open_mixdev(struct inode *inode, struct file *file)
{
	int minor = iminor(inode);
	struct list_head *list;
	struct vrc5477_ac97_state *s;

	for (list = devs.next; ; list = list->next) {
		if (list == &devs)
			return -ENODEV;
		s = list_entry(list, struct vrc5477_ac97_state, devs);
		if (s->codec->dev_mixer == minor)
			break;
	}
	file->private_data = s;
	return nonseekable_open(inode, file);
}

static int vrc5477_ac97_release_mixdev(struct inode *inode, struct file *file)
{
	return 0;
}


static int mixdev_ioctl(struct ac97_codec *codec, unsigned int cmd,
			unsigned long arg)
{
	return codec->mixer_ioctl(codec, cmd, arg);
}

static int vrc5477_ac97_ioctl_mixdev(struct inode *inode, struct file *file,
				     unsigned int cmd, unsigned long arg)
{
    struct vrc5477_ac97_state *s = 
	    (struct vrc5477_ac97_state *)file->private_data;
    struct ac97_codec *codec = s->codec;

    return mixdev_ioctl(codec, cmd, arg);
}

static /*const*/ struct file_operations vrc5477_ac97_mixer_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.ioctl		= vrc5477_ac97_ioctl_mixdev,
	.open		= vrc5477_ac97_open_mixdev,
	.release	= vrc5477_ac97_release_mixdev,
};

/* --------------------------------------------------------------------- */

static int drain_dac(struct vrc5477_ac97_state *s, int nonblock)
{
	unsigned long flags;
	int count, tmo;
	
	if (!s->dma_dac.ready)
		return 0;

	for (;;) {
		spin_lock_irqsave(&s->lock, flags);
		count = s->dma_dac.count;
		spin_unlock_irqrestore(&s->lock, flags);
		if (count <= 0)
			break;
		if (signal_pending(current))
			break;
		if (nonblock)
			return -EBUSY;
		tmo = 1000 * count / s->dacRate / 2;
		vrc5477_ac97_delay(tmo);
	}
	if (signal_pending(current))
		return -ERESTARTSYS;
	return 0;
}

/* --------------------------------------------------------------------- */

static inline int
copy_two_channel_adc_to_user(struct vrc5477_ac97_state *s, 
		             char *buffer, 
			     int copyCount)
{
	struct dmabuf *db = &s->dma_adc;
	int bufStart = db->nextOut;
	for (; copyCount > 0; ) {
		int i;
		int count = copyCount;
		if (count > WORK_BUF_SIZE/2) count = WORK_BUF_SIZE/2;
		for (i=0; i< count/2; i++) {
			s->workBuf[i].lchannel = 
				*(u16*)(db->lbuf + bufStart + i*2);
			s->workBuf[i].rchannel = 
				*(u16*)(db->rbuf + bufStart + i*2);
		}
		if (copy_to_user(buffer, s->workBuf, count*2)) {
			return -1;
		}

		copyCount -= count;
		bufStart += count;
		ASSERT(bufStart <= db->fragTotalSize);
		buffer += count *2;
	}
	return 0;
}

/* return the total bytes that is copied */
static inline int
copy_adc_to_user(struct vrc5477_ac97_state *s,
		 char * buffer,
		 size_t count,
		 int avail)
{
	struct dmabuf *db = &s->dma_adc;
	int copyCount=0;
	int copyFragCount=0;
	int totalCopyCount = 0;
	int totalCopyFragCount = 0;
	unsigned long flags;

	/* adjust count to signel channel byte count */
	count >>= s->adcChannels - 1;

	/* we may have to "copy" twice as ring buffer wraps around */
	for (; (avail > 0) && (count > 0); ) {
		/* determine max possible copy count for single channel */
		copyCount = count;
		if (copyCount > avail) {
			copyCount = avail;
		}
		if (copyCount + db->nextOut > db->fragTotalSize) {
			copyCount = db->fragTotalSize - db->nextOut;
			ASSERT((copyCount % db->fragSize) == 0);
		}

		copyFragCount = (copyCount-1) >> db->fragShift;
		copyFragCount = (copyFragCount+1) << db->fragShift;
		ASSERT(copyFragCount >= copyCount);

		/* we copy differently based on adc channels */
		if (s->adcChannels == 1) {
			if (copy_to_user(buffer, 
					 db->lbuf + db->nextOut, 
					 copyCount)) 
				return -1;
		} else {
			/* *sigh* we have to mix two streams into one  */
			if (copy_two_channel_adc_to_user(s, buffer, copyCount))
				return -1;
		}	

		count -= copyCount;
		totalCopyCount += copyCount;
		avail -= copyFragCount;
		totalCopyFragCount += copyFragCount;

		buffer += copyCount << (s->adcChannels-1);

		db->nextOut += copyFragCount;
		if (db->nextOut >= db->fragTotalSize) {
			ASSERT(db->nextOut == db->fragTotalSize);
			db->nextOut = 0;
		}

		ASSERT((copyFragCount % db->fragSize) == 0);
		ASSERT( (count == 0) || (copyCount == copyFragCount));
	}

	spin_lock_irqsave(&s->lock, flags);
        db->count -= totalCopyFragCount;
        spin_unlock_irqrestore(&s->lock, flags);

	return totalCopyCount << (s->adcChannels-1);
}

static ssize_t 
vrc5477_ac97_read(struct file *file, 
		  char *buffer,
		  size_t count, 
		  loff_t *ppos)
{
	struct vrc5477_ac97_state *s = 
		(struct vrc5477_ac97_state *)file->private_data;
	struct dmabuf *db = &s->dma_adc;
	ssize_t ret = 0;
	unsigned long flags;
	int copyCount;
	size_t avail;

	if (!access_ok(VERIFY_WRITE, buffer, count))
		return -EFAULT;

	ASSERT(db->ready);

	while (count > 0) {
		// wait for samples in capture buffer
		do {
			spin_lock_irqsave(&s->lock, flags);
			if (db->stopped)
				start_adc(s);
			avail = db->count;
			spin_unlock_irqrestore(&s->lock, flags);
			if (avail <= 0) {
				if (file->f_flags & O_NONBLOCK) {
					if (!ret)
						ret = -EAGAIN;
					return ret;
				}
				interruptible_sleep_on(&db->wait);
				if (signal_pending(current)) {
					if (!ret)
						ret = -ERESTARTSYS;
					return ret;
				}
			}
		} while (avail <= 0);

		ASSERT( (avail % db->fragSize) == 0);
		copyCount = copy_adc_to_user(s, buffer, count, avail);
		if (copyCount <=0 ) {
			if (!ret) ret = -EFAULT;
			return ret;
		}

		count -= copyCount;
		buffer += copyCount;
		ret += copyCount;
	} // while (count > 0)

	return ret;
}

static inline int
copy_two_channel_dac_from_user(struct vrc5477_ac97_state *s, 
			       const char *buffer, 
			       int copyCount)
{
	struct dmabuf *db = &s->dma_dac;
	int bufStart = db->nextIn;

	ASSERT(db->ready);

        for (; copyCount > 0; ) {
                int i;
                int count = copyCount;
                if (count > WORK_BUF_SIZE/2) count = WORK_BUF_SIZE/2;
                if (copy_from_user(s->workBuf, buffer, count*2)) {
                        return -1;
                }
                for (i=0; i< count/2; i++) {
			*(u16*)(db->lbuf + bufStart + i*2) = 
				s->workBuf[i].lchannel;
			*(u16*)(db->rbuf + bufStart + i*2) = 
				s->workBuf[i].rchannel;
                }

                copyCount -= count;
		bufStart += count;
		ASSERT(bufStart <= db->fragTotalSize);
                buffer += count *2;
        }
        return 0;

}

/* return the total bytes that is copied */
static inline int
copy_dac_from_user(struct vrc5477_ac97_state *s, 
		   const char *buffer, 
		   size_t count, 
		   int avail)
{	
        struct dmabuf *db = &s->dma_dac;
        int copyCount=0;
        int copyFragCount=0;
        int totalCopyCount = 0;
        int totalCopyFragCount = 0;
        unsigned long flags;
#if defined(VRC5477_AC97_VERBOSE_DEBUG)
	int i;
#endif

        /* adjust count to signel channel byte count */
        count >>= s->dacChannels - 1;

        /* we may have to "copy" twice as ring buffer wraps around */
        for (; (avail > 0) && (count > 0); ) {
                /* determine max possible copy count for single channel */
                copyCount = count;
                if (copyCount > avail) {
                        copyCount = avail;
		}
                if (copyCount + db->nextIn > db->fragTotalSize) {
                        copyCount = db->fragTotalSize - db->nextIn;
                        ASSERT(copyCount > 0);
                }

		copyFragCount = copyCount;
		ASSERT(copyFragCount >= copyCount);

		/* we copy differently based on the number channels */
		if (s->dacChannels == 1) {
			if (copy_from_user(db->lbuf + db->nextIn,
					   buffer,
					   copyCount)) 
				return -1;
			/* fill gaps with 0 */
			memset(db->lbuf + db->nextIn + copyCount,
			       0,
			       copyFragCount - copyCount);
		} else {
			/* we have demux the stream into two separate ones */
			if (copy_two_channel_dac_from_user(s, buffer, copyCount))
				return -1;
			/* fill gaps with 0 */
			memset(db->lbuf + db->nextIn + copyCount,
			       0,
			       copyFragCount - copyCount);
			memset(db->rbuf + db->nextIn + copyCount,
			       0,
			       copyFragCount - copyCount);
		}

#if defined(VRC5477_AC97_VERBOSE_DEBUG)
		for (i=0; i< copyFragCount; i+= db->fragSize) {
			*(u16*)(db->lbuf + db->nextIn + i) = inTicket ++;
		}
#endif

		count -= copyCount;
		totalCopyCount += copyCount;
		avail -= copyFragCount;
		totalCopyFragCount += copyFragCount;

		buffer += copyCount << (s->dacChannels - 1);

		db->nextIn += copyFragCount;
		if (db->nextIn >= db->fragTotalSize) {
			ASSERT(db->nextIn == db->fragTotalSize);
			db->nextIn = 0;
		}

		ASSERT( (count == 0) || (copyCount == copyFragCount));
	}

	spin_lock_irqsave(&s->lock, flags);
        db->count += totalCopyFragCount;
	if (db->stopped) {
		start_dac(s);
	}

	/* nextIn should not be equal to nextOut unless we are full */
	ASSERT( ( (db->count == db->fragTotalSize) && 
                       (db->nextIn == db->nextOut) ) ||
                     ( (db->count < db->fragTotalSize) &&
                       (db->nextIn != db->nextOut) ) );

        spin_unlock_irqrestore(&s->lock, flags);

        return totalCopyCount << (s->dacChannels-1);

}

static ssize_t vrc5477_ac97_write(struct file *file, const char *buffer,
				  size_t count, loff_t *ppos)
{
	struct vrc5477_ac97_state *s = 
		(struct vrc5477_ac97_state *)file->private_data;
	struct dmabuf *db = &s->dma_dac;
	ssize_t ret;
	unsigned long flags;
	int copyCount, avail;

	if (!access_ok(VERIFY_READ, buffer, count))
		return -EFAULT;
	ret = 0;
    
	while (count > 0) {
		// wait for space in playback buffer
		do {
			spin_lock_irqsave(&s->lock, flags);
			avail = db->fragTotalSize - db->count;
			spin_unlock_irqrestore(&s->lock, flags);
			if (avail <= 0) {
				if (file->f_flags & O_NONBLOCK) {
					if (!ret)
						ret = -EAGAIN;
					return ret;
				}
				interruptible_sleep_on(&db->wait);
				if (signal_pending(current)) {
					if (!ret)
						ret = -ERESTARTSYS;
					return ret;
				}
			}
		} while (avail <= 0);
	
		copyCount = copy_dac_from_user(s, buffer, count, avail);
		if (copyCount < 0) {
			if (!ret) ret = -EFAULT;
			return ret;
		}

		count -= copyCount;
		buffer += copyCount;
		ret += copyCount;
	} // while (count > 0)
	
	return ret;
}

/* No kernel lock - we have our own spinlock */
static unsigned int vrc5477_ac97_poll(struct file *file,
				      struct poll_table_struct *wait)
{
	struct vrc5477_ac97_state *s = (struct vrc5477_ac97_state *)file->private_data;
	unsigned long flags;
	unsigned int mask = 0;

	if (file->f_mode & FMODE_WRITE)
		poll_wait(file, &s->dma_dac.wait, wait);
	if (file->f_mode & FMODE_READ)
		poll_wait(file, &s->dma_adc.wait, wait);
	spin_lock_irqsave(&s->lock, flags);
	if (file->f_mode & FMODE_READ) {
		if (s->dma_adc.count >= (signed)s->dma_adc.fragSize)
			mask |= POLLIN | POLLRDNORM;
	}
	if (file->f_mode & FMODE_WRITE) {
		if ((signed)s->dma_dac.fragTotalSize >=
		    s->dma_dac.count + (signed)s->dma_dac.fragSize)
			mask |= POLLOUT | POLLWRNORM;
	}
	spin_unlock_irqrestore(&s->lock, flags);
	return mask;
}

#ifdef VRC5477_AC97_DEBUG
static struct ioctl_str_t {
    unsigned int cmd;
    const char* str;
} ioctl_str[] = {
    {SNDCTL_DSP_RESET, "SNDCTL_DSP_RESET"},
    {SNDCTL_DSP_SYNC, "SNDCTL_DSP_SYNC"},
    {SNDCTL_DSP_SPEED, "SNDCTL_DSP_SPEED"},
    {SNDCTL_DSP_STEREO, "SNDCTL_DSP_STEREO"},
    {SNDCTL_DSP_GETBLKSIZE, "SNDCTL_DSP_GETBLKSIZE"},
    {SNDCTL_DSP_SETFMT, "SNDCTL_DSP_SETFMT"},
    {SNDCTL_DSP_SAMPLESIZE, "SNDCTL_DSP_SAMPLESIZE"},
    {SNDCTL_DSP_CHANNELS, "SNDCTL_DSP_CHANNELS"},
    {SOUND_PCM_WRITE_CHANNELS, "SOUND_PCM_WRITE_CHANNELS"},
    {SOUND_PCM_WRITE_FILTER, "SOUND_PCM_WRITE_FILTER"},
    {SNDCTL_DSP_POST, "SNDCTL_DSP_POST"},
    {SNDCTL_DSP_SUBDIVIDE, "SNDCTL_DSP_SUBDIVIDE"},
    {SNDCTL_DSP_SETFRAGMENT, "SNDCTL_DSP_SETFRAGMENT"},
    {SNDCTL_DSP_GETFMTS, "SNDCTL_DSP_GETFMTS"},
    {SNDCTL_DSP_GETOSPACE, "SNDCTL_DSP_GETOSPACE"},
    {SNDCTL_DSP_GETISPACE, "SNDCTL_DSP_GETISPACE"},
    {SNDCTL_DSP_NONBLOCK, "SNDCTL_DSP_NONBLOCK"},
    {SNDCTL_DSP_GETCAPS, "SNDCTL_DSP_GETCAPS"},
    {SNDCTL_DSP_GETTRIGGER, "SNDCTL_DSP_GETTRIGGER"},
    {SNDCTL_DSP_SETTRIGGER, "SNDCTL_DSP_SETTRIGGER"},
    {SNDCTL_DSP_GETIPTR, "SNDCTL_DSP_GETIPTR"},
    {SNDCTL_DSP_GETOPTR, "SNDCTL_DSP_GETOPTR"},
    {SNDCTL_DSP_MAPINBUF, "SNDCTL_DSP_MAPINBUF"},
    {SNDCTL_DSP_MAPOUTBUF, "SNDCTL_DSP_MAPOUTBUF"},
    {SNDCTL_DSP_SETSYNCRO, "SNDCTL_DSP_SETSYNCRO"},
    {SNDCTL_DSP_SETDUPLEX, "SNDCTL_DSP_SETDUPLEX"},
    {SNDCTL_DSP_GETODELAY, "SNDCTL_DSP_GETODELAY"},
    {SNDCTL_DSP_GETCHANNELMASK, "SNDCTL_DSP_GETCHANNELMASK"},
    {SNDCTL_DSP_BIND_CHANNEL, "SNDCTL_DSP_BIND_CHANNEL"},
    {OSS_GETVERSION, "OSS_GETVERSION"},
    {SOUND_PCM_READ_RATE, "SOUND_PCM_READ_RATE"},
    {SOUND_PCM_READ_CHANNELS, "SOUND_PCM_READ_CHANNELS"},
    {SOUND_PCM_READ_BITS, "SOUND_PCM_READ_BITS"},
    {SOUND_PCM_READ_FILTER, "SOUND_PCM_READ_FILTER"}
};
#endif    

static int vrc5477_ac97_ioctl(struct inode *inode, struct file *file,
			unsigned int cmd, unsigned long arg)
{
	struct vrc5477_ac97_state *s = (struct vrc5477_ac97_state *)file->private_data;
	unsigned long flags;
	audio_buf_info abinfo;
	int count;
	int val, ret;

#ifdef VRC5477_AC97_DEBUG
	for (count=0; count<sizeof(ioctl_str)/sizeof(ioctl_str[0]); count++) {
		if (ioctl_str[count].cmd == cmd)
			break;
	}
	if (count < sizeof(ioctl_str)/sizeof(ioctl_str[0]))
		printk(KERN_INFO PFX "ioctl %s\n", ioctl_str[count].str);
	else
		printk(KERN_INFO PFX "ioctl unknown, 0x%x\n", cmd);
#endif
    
	switch (cmd) {
	case OSS_GETVERSION:
		return put_user(SOUND_VERSION, (int *)arg);

	case SNDCTL_DSP_SYNC:
		if (file->f_mode & FMODE_WRITE)
			return drain_dac(s, file->f_flags & O_NONBLOCK);
		return 0;
		
	case SNDCTL_DSP_SETDUPLEX:
		return 0;

	case SNDCTL_DSP_GETCAPS:
		return put_user(DSP_CAP_DUPLEX, (int *)arg);
		
	case SNDCTL_DSP_RESET:
		if (file->f_mode & FMODE_WRITE) {
			stop_dac(s);
			synchronize_irq(s->irq);
			s->dma_dac.count = 0;
			s->dma_dac.nextIn = s->dma_dac.nextOut = 0;
		}
		if (file->f_mode & FMODE_READ) {
			stop_adc(s);
			synchronize_irq(s->irq);
			s->dma_adc.count = 0;
			s->dma_adc.nextIn = s->dma_adc.nextOut = 0;
		}
		return 0;

	case SNDCTL_DSP_SPEED:
		if (get_user(val, (int *)arg))
			return -EFAULT;
		if (val >= 0) {
			if (file->f_mode & FMODE_READ) {
				stop_adc(s);
				set_adc_rate(s, val);
				if ((ret = prog_dmabuf_adc(s)))
					return ret;
			}
			if (file->f_mode & FMODE_WRITE) {
				stop_dac(s);
				set_dac_rate(s, val);
				if ((ret = prog_dmabuf_dac(s)))
					return ret;
			}
		}
		return put_user((file->f_mode & FMODE_READ) ?
				s->adcRate : s->dacRate, (int *)arg);

	case SNDCTL_DSP_STEREO:
		if (get_user(val, (int *)arg))
			return -EFAULT;
		if (file->f_mode & FMODE_READ) {
			stop_adc(s);
			if (val)
				s->adcChannels = 2;
			else
				s->adcChannels = 1;
			if ((ret = prog_dmabuf_adc(s)))
				return ret;
		}
		if (file->f_mode & FMODE_WRITE) {
			stop_dac(s);
			if (val)
				s->dacChannels = 2;
			else
				s->dacChannels = 1;
			if ((ret = prog_dmabuf_dac(s)))
				return ret;
		}
		return 0;

	case SNDCTL_DSP_CHANNELS:
		if (get_user(val, (int *)arg))
			return -EFAULT;
		if (val != 0) {
			if ( (val != 1) && (val != 2)) val = 2;

			if (file->f_mode & FMODE_READ) {
				stop_adc(s);
				s->dacChannels = val;
				if ((ret = prog_dmabuf_adc(s)))
					return ret;
			}
			if (file->f_mode & FMODE_WRITE) {
				stop_dac(s);
				s->dacChannels = val;
				if ((ret = prog_dmabuf_dac(s)))
					return ret;
			}
		}
		return put_user(val, (int *)arg);
		
	case SNDCTL_DSP_GETFMTS: /* Returns a mask */
		return put_user(AFMT_S16_LE, (int *)arg);
		
	case SNDCTL_DSP_SETFMT: /* Selects ONE fmt*/
		if (get_user(val, (int *)arg))
			return -EFAULT;
		if (val != AFMT_QUERY) {
			if (val != AFMT_S16_LE) return -EINVAL;
			if (file->f_mode & FMODE_READ) {
				stop_adc(s);
				if ((ret = prog_dmabuf_adc(s)))
					return ret;
			}
			if (file->f_mode & FMODE_WRITE) {
				stop_dac(s);
				if ((ret = prog_dmabuf_dac(s)))
					return ret;
			}
		} else {
			val = AFMT_S16_LE;
		}
		return put_user(val, (int *)arg);
		
	case SNDCTL_DSP_POST:
		return 0;

	case SNDCTL_DSP_GETTRIGGER:
	case SNDCTL_DSP_SETTRIGGER:
		/* NO trigger */
		return -EINVAL;

	case SNDCTL_DSP_GETOSPACE:
		if (!(file->f_mode & FMODE_WRITE))
			return -EINVAL;
		abinfo.fragsize = s->dma_dac.fragSize << (s->dacChannels-1);
		spin_lock_irqsave(&s->lock, flags);
		count = s->dma_dac.count;
		spin_unlock_irqrestore(&s->lock, flags);
		abinfo.bytes = (s->dma_dac.fragTotalSize - count) << 
			(s->dacChannels-1);
		abinfo.fragstotal = s->dma_dac.numFrag;
		abinfo.fragments = abinfo.bytes >> s->dma_dac.fragShift >> 
			(s->dacChannels-1);      
		return copy_to_user((void *)arg, &abinfo, sizeof(abinfo)) ? -EFAULT : 0;

	case SNDCTL_DSP_GETISPACE:
		if (!(file->f_mode & FMODE_READ))
			return -EINVAL;
		abinfo.fragsize = s->dma_adc.fragSize << (s->adcChannels-1);
		spin_lock_irqsave(&s->lock, flags);
		count = s->dma_adc.count;
		spin_unlock_irqrestore(&s->lock, flags);
		if (count < 0)
			count = 0;
		abinfo.bytes = count << (s->adcChannels-1);
		abinfo.fragstotal = s->dma_adc.numFrag;
		abinfo.fragments = (abinfo.bytes >> s->dma_adc.fragShift) >>
			(s->adcChannels-1);      
		return copy_to_user((void *)arg, &abinfo, sizeof(abinfo)) ? -EFAULT : 0;
		
	case SNDCTL_DSP_NONBLOCK:
		file->f_flags |= O_NONBLOCK;
		return 0;

	case SNDCTL_DSP_GETODELAY:
		if (!(file->f_mode & FMODE_WRITE))
			return -EINVAL;
		spin_lock_irqsave(&s->lock, flags);
		count = s->dma_dac.count;
		spin_unlock_irqrestore(&s->lock, flags);
		return put_user(count, (int *)arg);

	case SNDCTL_DSP_GETIPTR:
	case SNDCTL_DSP_GETOPTR:
		/* we cannot get DMA ptr */
		return -EINVAL;

	case SNDCTL_DSP_GETBLKSIZE:
		if (file->f_mode & FMODE_WRITE)
			return put_user(s->dma_dac.fragSize << (s->dacChannels-1), (int *)arg);
		else
			return put_user(s->dma_adc.fragSize << (s->adcChannels-1), (int *)arg);

	case SNDCTL_DSP_SETFRAGMENT:
		/* we ignore fragment size request */
		return 0;

	case SNDCTL_DSP_SUBDIVIDE:
		/* what is this for? [jsun] */
		return 0;

	case SOUND_PCM_READ_RATE:
		return put_user((file->f_mode & FMODE_READ) ?
				s->adcRate : s->dacRate, (int *)arg);

	case SOUND_PCM_READ_CHANNELS:
		if (file->f_mode & FMODE_READ)
			return put_user(s->adcChannels, (int *)arg);
		else
			return put_user(s->dacChannels ? 2 : 1, (int *)arg);
	    
	case SOUND_PCM_READ_BITS:
		return put_user(16, (int *)arg);

	case SOUND_PCM_WRITE_FILTER:
	case SNDCTL_DSP_SETSYNCRO:
	case SOUND_PCM_READ_FILTER:
		return -EINVAL;
	}

	return mixdev_ioctl(s->codec, cmd, arg);
}


static int vrc5477_ac97_open(struct inode *inode, struct file *file)
{
	int minor = iminor(inode);
	DECLARE_WAITQUEUE(wait, current);
	unsigned long flags;
	struct list_head *list;
	struct vrc5477_ac97_state *s;
	int ret=0;

	nonseekable_open(inode, file);    
	for (list = devs.next; ; list = list->next) {
		if (list == &devs)
			return -ENODEV;
		s = list_entry(list, struct vrc5477_ac97_state, devs);
		if (!((s->dev_audio ^ minor) & ~0xf))
			break;
	}
	file->private_data = s;

	/* wait for device to become free */
	mutex_lock(&s->open_mutex);
	while (s->open_mode & file->f_mode) {

		if (file->f_flags & O_NONBLOCK) {
			mutex_unlock(&s->open_mutex);
			return -EBUSY;
		}
		add_wait_queue(&s->open_wait, &wait);
		__set_current_state(TASK_INTERRUPTIBLE);
		mutex_unlock(&s->open_mutex);
		schedule();
		remove_wait_queue(&s->open_wait, &wait);
		set_current_state(TASK_RUNNING);
		if (signal_pending(current))
			return -ERESTARTSYS;
		mutex_lock(&s->open_mutex);
	}

	spin_lock_irqsave(&s->lock, flags);

	if (file->f_mode & FMODE_READ) {
		/* set default settings */
		set_adc_rate(s, 48000);
		s->adcChannels = 2;

		ret = prog_dmabuf_adc(s);
		if (ret) goto bailout;
	}
	if (file->f_mode & FMODE_WRITE) {
		/* set default settings */
		set_dac_rate(s, 48000);
		s->dacChannels = 2;

		ret = prog_dmabuf_dac(s);
		if (ret) goto bailout;
	}

	s->open_mode |= file->f_mode & (FMODE_READ | FMODE_WRITE);

 bailout:
	spin_unlock_irqrestore(&s->lock, flags);

	mutex_unlock(&s->open_mutex);
	return ret;
}

static int vrc5477_ac97_release(struct inode *inode, struct file *file)
{
	struct vrc5477_ac97_state *s = 
		(struct vrc5477_ac97_state *)file->private_data;

	lock_kernel();
	if (file->f_mode & FMODE_WRITE)
		drain_dac(s, file->f_flags & O_NONBLOCK);
	mutex_lock(&s->open_mutex);
	if (file->f_mode & FMODE_WRITE) {
		stop_dac(s);
		dealloc_dmabuf(s, &s->dma_dac);
	}
	if (file->f_mode & FMODE_READ) {
		stop_adc(s);
		dealloc_dmabuf(s, &s->dma_adc);
	}
	s->open_mode &= (~file->f_mode) & (FMODE_READ|FMODE_WRITE);
	mutex_unlock(&s->open_mutex);
	wake_up(&s->open_wait);
	unlock_kernel();
	return 0;
}

static /*const*/ struct file_operations vrc5477_ac97_audio_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.read		= vrc5477_ac97_read,
	.write		= vrc5477_ac97_write,
	.poll		= vrc5477_ac97_poll,
	.ioctl		= vrc5477_ac97_ioctl,
	// .mmap	= vrc5477_ac97_mmap,
	.open		= vrc5477_ac97_open,
	.release	= vrc5477_ac97_release,
};


/* --------------------------------------------------------------------- */


/* --------------------------------------------------------------------- */

/*
 * for debugging purposes, we'll create a proc device that dumps the
 * CODEC chipstate
 */

#ifdef VRC5477_AC97_DEBUG

struct {
       const char *regname;
       unsigned regaddr;
} vrc5477_ac97_regs[] = {
	{"VRC5477_INT_STATUS", VRC5477_INT_STATUS},
	{"VRC5477_CODEC_WR", VRC5477_CODEC_WR},
	{"VRC5477_CODEC_RD", VRC5477_CODEC_RD},
	{"VRC5477_CTRL", VRC5477_CTRL},
	{"VRC5477_ACLINK_CTRL", VRC5477_ACLINK_CTRL},
	{"VRC5477_INT_MASK", VRC5477_INT_MASK},
	{"VRC5477_DAC1_CTRL", VRC5477_DAC1_CTRL},
	{"VRC5477_DAC1L", VRC5477_DAC1L},
	{"VRC5477_DAC1_BADDR", VRC5477_DAC1_BADDR},
	{"VRC5477_DAC2_CTRL", VRC5477_DAC2_CTRL},
	{"VRC5477_DAC2L", VRC5477_DAC2L},
	{"VRC5477_DAC2_BADDR", VRC5477_DAC2_BADDR},
	{"VRC5477_DAC3_CTRL", VRC5477_DAC3_CTRL},
	{"VRC5477_DAC3L", VRC5477_DAC3L},
	{"VRC5477_DAC3_BADDR", VRC5477_DAC3_BADDR},
	{"VRC5477_ADC1_CTRL", VRC5477_ADC1_CTRL},
	{"VRC5477_ADC1L", VRC5477_ADC1L},
	{"VRC5477_ADC1_BADDR", VRC5477_ADC1_BADDR},
	{"VRC5477_ADC2_CTRL", VRC5477_ADC2_CTRL},
	{"VRC5477_ADC2L", VRC5477_ADC2L},
	{"VRC5477_ADC2_BADDR", VRC5477_ADC2_BADDR},
	{"VRC5477_ADC3_CTRL", VRC5477_ADC3_CTRL},
	{"VRC5477_ADC3L", VRC5477_ADC3L},
	{"VRC5477_ADC3_BADDR", VRC5477_ADC3_BADDR},
	{NULL, 0x0}
};

static int proc_vrc5477_ac97_dump (char *buf, char **start, off_t fpos,
				   int length, int *eof, void *data)
{
	struct vrc5477_ac97_state *s;
	int cnt, len = 0;

	if (list_empty(&devs))
		return 0;
	s = list_entry(devs.next, struct vrc5477_ac97_state, devs);

	/* print out header */
	len += sprintf(buf + len, "\n\t\tVrc5477 Audio Debug\n\n");

	// print out digital controller state
	len += sprintf (buf + len, "NEC Vrc5477 Audio Controller registers\n");
	len += sprintf (buf + len, "---------------------------------\n");
	for (cnt=0; vrc5477_ac97_regs[cnt].regname != NULL; cnt++) {
		len+= sprintf (buf + len, "%-20s = %08x\n",
			       vrc5477_ac97_regs[cnt].regname,
			       inl(s->io + vrc5477_ac97_regs[cnt].regaddr));
	}
   
	/* print out driver state */
	len += sprintf (buf + len, "NEC Vrc5477 Audio driver states\n");
	len += sprintf (buf + len, "---------------------------------\n");
	len += sprintf (buf + len, "dacChannels  = %d\n", s->dacChannels);
	len += sprintf (buf + len, "adcChannels  = %d\n", s->adcChannels);
	len += sprintf (buf + len, "dacRate  = %d\n", s->dacRate);
	len += sprintf (buf + len, "adcRate  = %d\n", s->adcRate);

	len += sprintf (buf + len, "dma_dac is %s ready\n",  
	                s->dma_dac.ready? "" : "not");
        if (s->dma_dac.ready) {
		len += sprintf (buf + len, "dma_dac is %s stopped.\n",  
	                        s->dma_dac.stopped? "" : "not");
		len += sprintf (buf + len, "dma_dac.fragSize = %x\n", 
                                s->dma_dac.fragSize);
		len += sprintf (buf + len, "dma_dac.fragShift = %x\n", 
                                s->dma_dac.fragShift);
		len += sprintf (buf + len, "dma_dac.numFrag = %x\n", 
                                s->dma_dac.numFrag);
		len += sprintf (buf + len, "dma_dac.fragTotalSize = %x\n", 
                                s->dma_dac.fragTotalSize);
		len += sprintf (buf + len, "dma_dac.nextIn = %x\n", 
                                s->dma_dac.nextIn);
		len += sprintf (buf + len, "dma_dac.nextOut = %x\n", 
                                s->dma_dac.nextOut);
		len += sprintf (buf + len, "dma_dac.count = %x\n", 
                                s->dma_dac.count);
	}

	len += sprintf (buf + len, "dma_adc is %s ready\n",  
	                s->dma_adc.ready? "" : "not");
        if (s->dma_adc.ready) {
		len += sprintf (buf + len, "dma_adc is %s stopped.\n",  
	                        s->dma_adc.stopped? "" : "not");
		len += sprintf (buf + len, "dma_adc.fragSize = %x\n", 
                                s->dma_adc.fragSize);
		len += sprintf (buf + len, "dma_adc.fragShift = %x\n", 
                                s->dma_adc.fragShift);
		len += sprintf (buf + len, "dma_adc.numFrag = %x\n", 
                                s->dma_adc.numFrag);
		len += sprintf (buf + len, "dma_adc.fragTotalSize = %x\n", 
                                s->dma_adc.fragTotalSize);
		len += sprintf (buf + len, "dma_adc.nextIn = %x\n", 
                                s->dma_adc.nextIn);
		len += sprintf (buf + len, "dma_adc.nextOut = %x\n", 
                                s->dma_adc.nextOut);
		len += sprintf (buf + len, "dma_adc.count = %x\n", 
                                s->dma_adc.count);
	}
	 
	/* print out CODEC state */
	len += sprintf (buf + len, "\nAC97 CODEC registers\n");
	len += sprintf (buf + len, "----------------------\n");
	for (cnt=0; cnt <= 0x7e; cnt = cnt +2)
		len+= sprintf (buf + len, "reg %02x = %04x\n",
			       cnt, rdcodec(s->codec, cnt));

	if (fpos >=len){
		*start = buf;
		*eof =1;
		return 0;
	}
	*start = buf + fpos;
	if ((len -= fpos) > length)
		return length;
	*eof =1;
	return len;

}
#endif /* VRC5477_AC97_DEBUG */

/* --------------------------------------------------------------------- */

/* maximum number of devices; only used for command line params */
#define NR_DEVICE 5

static unsigned int devindex;

MODULE_AUTHOR("Monta Vista Software, jsun@mvista.com or jsun@junsun.net");
MODULE_DESCRIPTION("NEC Vrc5477 audio (AC97) Driver");
MODULE_LICENSE("GPL");

static int __devinit vrc5477_ac97_probe(struct pci_dev *pcidev,
					const struct pci_device_id *pciid)
{
	struct vrc5477_ac97_state *s;
#ifdef VRC5477_AC97_DEBUG
	char proc_str[80];
#endif

	if (pcidev->irq == 0) 
		return -1;

	if (!(s = kmalloc(sizeof(struct vrc5477_ac97_state), GFP_KERNEL))) {
		printk(KERN_ERR PFX "alloc of device struct failed\n");
		return -1;
	}
	memset(s, 0, sizeof(struct vrc5477_ac97_state));

	init_waitqueue_head(&s->dma_adc.wait);
	init_waitqueue_head(&s->dma_dac.wait);
	init_waitqueue_head(&s->open_wait);
	mutex_init(&s->open_mutex);
	spin_lock_init(&s->lock);

	s->dev = pcidev;
	s->io = pci_resource_start(pcidev, 0);
	s->irq = pcidev->irq;
	
	s->codec = ac97_alloc_codec();

	s->codec->private_data = s;
	s->codec->id = 0;
	s->codec->codec_read = rdcodec;
	s->codec->codec_write = wrcodec;
	s->codec->codec_wait = waitcodec;

	/* setting some other default values such as
	 * adcChannels, adcRate is done in open() so that
         * no persistent state across file opens.
	 */

	/* test if get response from ac97, if not return */
        if (ac97_codec_not_present(s->codec)) {
		printk(KERN_ERR PFX "no ac97 codec\n");
		goto err_region;

        }

	/* test if get response from ac97, if not return */
        if (ac97_codec_not_present(&(s->codec))) {
		printk(KERN_ERR PFX "no ac97 codec\n");
		goto err_region;

        }

	if (!request_region(s->io, pci_resource_len(pcidev,0),
			    VRC5477_AC97_MODULE_NAME)) {
		printk(KERN_ERR PFX "io ports %#lx->%#lx in use\n",
		       s->io, s->io + pci_resource_len(pcidev,0)-1);
		goto err_region;
	}
	if (request_irq(s->irq, vrc5477_ac97_interrupt, SA_INTERRUPT,
			VRC5477_AC97_MODULE_NAME, s)) {
		printk(KERN_ERR PFX "irq %u in use\n", s->irq);
		goto err_irq;
	}

	printk(KERN_INFO PFX "IO at %#lx, IRQ %d\n", s->io, s->irq);

	/* register devices */
	if ((s->dev_audio = register_sound_dsp(&vrc5477_ac97_audio_fops, -1)) < 0)
		goto err_dev1;
	if ((s->codec->dev_mixer =
	     register_sound_mixer(&vrc5477_ac97_mixer_fops, -1)) < 0)
		goto err_dev2;

#ifdef VRC5477_AC97_DEBUG
	/* initialize the debug proc device */
	s->ps = create_proc_read_entry(VRC5477_AC97_MODULE_NAME, 0, NULL,
				       proc_vrc5477_ac97_dump, NULL);
#endif /* VRC5477_AC97_DEBUG */
	
	/* enable pci io and bus mastering */
	if (pci_enable_device(pcidev))
		goto err_dev3;
	pci_set_master(pcidev);

	/* cold reset the AC97 */
	outl(VRC5477_ACLINK_CTRL_RST_ON | VRC5477_ACLINK_CTRL_RST_TIME,
	     s->io + VRC5477_ACLINK_CTRL);
	while (inl(s->io + VRC5477_ACLINK_CTRL) & VRC5477_ACLINK_CTRL_RST_ON);

	/* codec init */
	if (!ac97_probe_codec(s->codec))
		goto err_dev3;

#ifdef VRC5477_AC97_DEBUG
	sprintf(proc_str, "driver/%s/%d/ac97", 
		VRC5477_AC97_MODULE_NAME, s->codec->id);
	s->ac97_ps = create_proc_read_entry (proc_str, 0, NULL,
					     ac97_read_proc, s->codec);
	/* TODO : why this proc file does not show up? */
#endif

	/* Try to enable variable rate audio mode. */
	wrcodec(s->codec, AC97_EXTENDED_STATUS,
		rdcodec(s->codec, AC97_EXTENDED_STATUS) | AC97_EXTSTAT_VRA);
	/* Did we enable it? */
	if(rdcodec(s->codec, AC97_EXTENDED_STATUS) & AC97_EXTSTAT_VRA)
		s->extended_status |= AC97_EXTSTAT_VRA;
	else {
		s->dacRate = 48000;
		printk(KERN_INFO PFX "VRA mode not enabled; rate fixed at %d.",
			s->dacRate);
	}

        /* let us get the default volumne louder */
        wrcodec(s->codec, 0x2, 0x1010);	/* master volume, middle */
        wrcodec(s->codec, 0xc, 0x10);		/* phone volume, middle */
        // wrcodec(s->codec, 0xe, 0x10);		/* misc volume, middle */
	wrcodec(s->codec, 0x10, 0x8000);	/* line-in 2 line-out disable */
        wrcodec(s->codec, 0x18, 0x0707);	/* PCM out (line out) middle */


	/* by default we select line in the input */
	wrcodec(s->codec, 0x1a, 0x0404);
	wrcodec(s->codec, 0x1c, 0x0f0f);
	wrcodec(s->codec, 0x1e, 0x07);

	/* enable the master interrupt but disable all others */
	outl(VRC5477_INT_MASK_NMASK, s->io + VRC5477_INT_MASK);

	/* store it in the driver field */
	pci_set_drvdata(pcidev, s);
	pcidev->dma_mask = 0xffffffff;
	/* put it into driver list */
	list_add_tail(&s->devs, &devs);
	/* increment devindex */
	if (devindex < NR_DEVICE-1)
		devindex++;
	return 0;

 err_dev3:
	unregister_sound_mixer(s->codec->dev_mixer);
 err_dev2:
	unregister_sound_dsp(s->dev_audio);
 err_dev1:
	printk(KERN_ERR PFX "cannot register misc device\n");
	free_irq(s->irq, s);
 err_irq:
	release_region(s->io, pci_resource_len(pcidev,0));
 err_region:
 	ac97_release_codec(codec);
	kfree(s);
	return -1;
}

static void __devexit vrc5477_ac97_remove(struct pci_dev *dev)
{
	struct vrc5477_ac97_state *s = pci_get_drvdata(dev);

	if (!s)
		return;
	list_del(&s->devs);

#ifdef VRC5477_AC97_DEBUG
	if (s->ps)
		remove_proc_entry(VRC5477_AC97_MODULE_NAME, NULL);
#endif /* VRC5477_AC97_DEBUG */

	synchronize_irq();
	free_irq(s->irq, s);
	release_region(s->io, pci_resource_len(dev,0));
	unregister_sound_dsp(s->dev_audio);
	unregister_sound_mixer(s->codec->dev_mixer);
	ac97_release_codec(s->codec);
	kfree(s);
	pci_set_drvdata(dev, NULL);
}


static struct pci_device_id id_table[] = {
    { PCI_VENDOR_ID_NEC, PCI_DEVICE_ID_NEC_VRC5477_AC97, 
      PCI_ANY_ID, PCI_ANY_ID, 0, 0 },
    { 0, }
};

MODULE_DEVICE_TABLE(pci, id_table);

static struct pci_driver vrc5477_ac97_driver = {
	.name		= VRC5477_AC97_MODULE_NAME,
	.id_table	= id_table,
	.probe		= vrc5477_ac97_probe,
	.remove		= __devexit_p(vrc5477_ac97_remove)
};

static int __init init_vrc5477_ac97(void)
{
	printk("Vrc5477 AC97 driver: version v0.2 time " __TIME__ " " __DATE__ " by Jun Sun\n");
	return pci_register_driver(&vrc5477_ac97_driver);
}

static void __exit cleanup_vrc5477_ac97(void)
{
	printk(KERN_INFO PFX "unloading\n");
	pci_unregister_driver(&vrc5477_ac97_driver);
}

module_init(init_vrc5477_ac97);
module_exit(cleanup_vrc5477_ac97);