aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/isdn/mISDN/dsp_cmx.c
blob: e92b1ba4b45eb836d83ef101564c76311644ed2e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
/*
 * Audio crossconnecting/conferrencing (hardware level).
 *
 * Copyright 2002 by Andreas Eversberg (jolly@eversberg.eu)
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 *
 */

/*
 * The process of adding and removing parties to/from a conference:
 *
 * There is a chain of struct dsp_conf which has one or more members in a chain
 * of struct dsp_conf_member.
 *
 * After a party is added, the conference is checked for hardware capability.
 * Also if a party is removed, the conference is checked again.
 *
 * There are 3 different solutions: -1 = software, 0 = hardware-crossconnect
 * 1-n = hardware-conference. The n will give the conference number.
 *
 * Depending on the change after removal or insertion of a party, hardware
 * commands are given.
 *
 * The current solution is stored within the struct dsp_conf entry.
 */

/*
 * HOW THE CMX WORKS:
 *
 * There are 3 types of interaction: One member is alone, in this case only
 * data flow from upper to lower layer is done.
 * Two members will also exchange their data so they are crossconnected.
 * Three or more members will be added in a conference and will hear each
 * other but will not receive their own speech (echo) if not enabled.
 *
 * Features of CMX are:
 *  - Crossconnecting or even conference, if more than two members are together.
 *  - Force mixing of transmit data with other crossconnect/conference members.
 *  - Echo generation to benchmark the delay of audio processing.
 *  - Use hardware to minimize cpu load, disable FIFO load and minimize delay.
 *  - Dejittering and clock generation.
 *
 * There are 2 buffers:
 *
 *
 * RX-Buffer
 *                 R             W
 *                 |             |
 * ----------------+-------------+-------------------
 *
 * The rx-buffer is a ring buffer used to store the received data for each
 * individual member. This is only the case if data needs to be dejittered
 * or in case of a conference where different clocks require reclocking.
 * The transmit-clock (R) will read the buffer.
 * If the clock overruns the write-pointer, we will have a buffer underrun.
 * If the write pointer always has a certain distance from the transmit-
 * clock, we will have a delay. The delay will dynamically be increased and
 * reduced.
 *
 *
 * TX-Buffer
 *                  R        W
 *                  |        |
 * -----------------+--------+-----------------------
 *
 * The tx-buffer is a ring buffer to queue the transmit data from user space
 * until it will be mixed or sent. There are two pointers, R and W. If the write
 * pointer W would reach or overrun R, the buffer would overrun. In this case
 * (some) data is dropped so that it will not overrun.
 * Additionally a dynamic dejittering can be enabled. this allows data from
 * user space that have jitter and different clock source.
 *
 *
 * Clock:
 *
 * A Clock is not required, if the data source has exactly one clock. In this
 * case the data source is forwarded to the destination.
 *
 * A Clock is required, because the data source
 *  - has multiple clocks.
 *  - has no usable clock due to jitter or packet loss (VoIP).
 * In this case the system's clock is used. The clock resolution depends on
 * the jiffie resolution.
 *
 * If a member joins a conference:
 *
 * - If a member joins, its rx_buff is set to silence and change read pointer
 *   to transmit clock.
 *
 * The procedure of received data from card is explained in cmx_receive.
 * The procedure of received data from user space is explained in cmx_transmit.
 * The procedure of transmit data to card is cmx_send.
 *
 *
 * Interaction with other features:
 *
 * DTMF:
 * DTMF decoding is done before the data is crossconnected.
 *
 * Volume change:
 * Changing rx-volume is done before the data is crossconnected. The tx-volume
 * must be changed whenever data is transmitted to the card by the cmx.
 *
 * Tones:
 * If a tone is enabled, it will be processed whenever data is transmitted to
 * the card. It will replace the tx-data from the user space.
 * If tones are generated by hardware, this conference member is removed for
 * this time.
 *
 * Disable rx-data:
 * If cmx is realized in hardware, rx data will be disabled if requested by
 * the upper layer. If dtmf decoding is done by software and enabled, rx data
 * will not be diabled but blocked to the upper layer.
 *
 * HFC conference engine:
 * If it is possible to realize all features using hardware, hardware will be
 * used if not forbidden by control command. Disabling rx-data provides
 * absolutely traffic free audio processing. (except for the quick 1-frame
 * upload of a tone loop, only once for a new tone)
 *
 */

/* delay.h is required for hw_lock.h */

#include <linux/delay.h>
#include <linux/mISDNif.h>
#include <linux/mISDNdsp.h>
#include "core.h"
#include "dsp.h"
/*
 * debugging of multi party conference,
 * by using conference even with two members
 */

/* #define CMX_CONF_DEBUG */

/*#define CMX_DEBUG * massive read/write pointer output */
/*#define CMX_TX_DEBUG * massive read/write on tx-buffer with content */

static inline int
count_list_member(struct list_head *head)
{
	int			cnt = 0;
	struct list_head	*m;

	list_for_each(m, head)
		cnt++;
	return cnt;
}

/*
 * debug cmx memory structure
 */
void
dsp_cmx_debug(struct dsp *dsp)
{
	struct dsp_conf	*conf;
	struct dsp_conf_member	*member;
	struct dsp		*odsp;

	printk(KERN_DEBUG "-----Current DSP\n");
	list_for_each_entry(odsp, &dsp_ilist, list) {
		printk(KERN_DEBUG "* %s echo=%d txmix=%d",
		    odsp->name, odsp->echo, odsp->tx_mix);
		if (odsp->conf)
			printk(" (Conf %d)", odsp->conf->id);
		if (dsp == odsp)
			printk(" *this*");
		printk("\n");
	}
	printk(KERN_DEBUG "-----Current Conf:\n");
	list_for_each_entry(conf, &conf_ilist, list) {
		printk(KERN_DEBUG "* Conf %d (%p)\n", conf->id, conf);
		list_for_each_entry(member, &conf->mlist, list) {
			printk(KERN_DEBUG
			    "  - member = %s (slot_tx %d, bank_tx %d, "
			    "slot_rx %d, bank_rx %d hfc_conf %d)%s\n",
			    member->dsp->name, member->dsp->pcm_slot_tx,
			    member->dsp->pcm_bank_tx, member->dsp->pcm_slot_rx,
			    member->dsp->pcm_bank_rx, member->dsp->hfc_conf,
			    (member->dsp == dsp) ? " *this*" : "");
		}
	}
	printk(KERN_DEBUG "-----end\n");
}

/*
 * search conference
 */
static struct dsp_conf *
dsp_cmx_search_conf(u32 id)
{
	struct dsp_conf *conf;

	if (!id) {
		printk(KERN_WARNING "%s: conference ID is 0.\n", __func__);
		return NULL;
	}

	/* search conference */
	list_for_each_entry(conf, &conf_ilist, list)
		if (conf->id == id)
			return conf;

	return NULL;
}


/*
 * add member to conference
 */
static int
dsp_cmx_add_conf_member(struct dsp *dsp, struct dsp_conf *conf)
{
	struct dsp_conf_member *member;

	if (!conf || !dsp) {
		printk(KERN_WARNING "%s: conf or dsp is 0.\n", __func__);
		return -EINVAL;
	}
	if (dsp->member) {
		printk(KERN_WARNING "%s: dsp is already member in a conf.\n",
			__func__);
		return -EINVAL;
	}

	if (dsp->conf) {
		printk(KERN_WARNING "%s: dsp is already in a conf.\n",
			__func__);
		return -EINVAL;
	}

	member = kzalloc(sizeof(struct dsp_conf_member), GFP_ATOMIC);
	if (!member) {
		printk(KERN_ERR "kmalloc struct dsp_conf_member failed\n");
		return -ENOMEM;
	}
	member->dsp = dsp;
	/* clear rx buffer */
	memset(dsp->rx_buff, dsp_silence, sizeof(dsp->rx_buff));
	dsp->rx_init = 1; /* rx_W and rx_R will be adjusted on first frame */
	dsp->rx_W = 0;
	dsp->rx_R = 0;

	list_add_tail(&member->list, &conf->mlist);

	dsp->conf = conf;
	dsp->member = member;

	return 0;
}


/*
 * del member from conference
 */
int
dsp_cmx_del_conf_member(struct dsp *dsp)
{
	struct dsp_conf_member *member;

	if (!dsp) {
		printk(KERN_WARNING "%s: dsp is 0.\n",
			__func__);
		return -EINVAL;
	}

	if (!dsp->conf) {
		printk(KERN_WARNING "%s: dsp is not in a conf.\n",
			__func__);
		return -EINVAL;
	}

	if (list_empty(&dsp->conf->mlist)) {
		printk(KERN_WARNING "%s: dsp has linked an empty conf.\n",
			__func__);
		return -EINVAL;
	}

	/* find us in conf */
	list_for_each_entry(member, &dsp->conf->mlist, list) {
		if (member->dsp == dsp) {
			list_del(&member->list);
			dsp->conf = NULL;
			dsp->member = NULL;
			kfree(member);
			return 0;
		}
	}
	printk(KERN_WARNING
	    "%s: dsp is not present in its own conf_meber list.\n",
	    __func__);

	return -EINVAL;
}


/*
 * new conference
 */
static struct dsp_conf
*dsp_cmx_new_conf(u32 id)
{
	struct dsp_conf *conf;

	if (!id) {
		printk(KERN_WARNING "%s: id is 0.\n",
		    __func__);
		return NULL;
	}

	conf = kzalloc(sizeof(struct dsp_conf), GFP_ATOMIC);
	if (!conf) {
		printk(KERN_ERR "kmalloc struct dsp_conf failed\n");
		return NULL;
	}
	INIT_LIST_HEAD(&conf->mlist);
	conf->id = id;

	list_add_tail(&conf->list, &conf_ilist);

	return conf;
}


/*
 * del conference
 */
int
dsp_cmx_del_conf(struct dsp_conf *conf)
{
	if (!conf) {
		printk(KERN_WARNING "%s: conf is null.\n",
		    __func__);
		return -EINVAL;
	}

	if (!list_empty(&conf->mlist)) {
		printk(KERN_WARNING "%s: conf not empty.\n",
		    __func__);
		return -EINVAL;
	}
	list_del(&conf->list);
	kfree(conf);

	return 0;
}


/*
 * send HW message to hfc card
 */
static void
dsp_cmx_hw_message(struct dsp *dsp, u32 message, u32 param1, u32 param2,
    u32 param3, u32 param4)
{
	struct mISDN_ctrl_req cq;

	memset(&cq, 0, sizeof(cq));
	cq.op = message;
	cq.p1 = param1 | (param2 << 8);
	cq.p2 = param3 | (param4 << 8);
	if (dsp->ch.peer)
		dsp->ch.peer->ctrl(dsp->ch.peer, CONTROL_CHANNEL, &cq);
}


/*
 * do hardware update and set the software/hardware flag
 *
 * either a conference or a dsp instance can be given
 * if only dsp instance is given, the instance is not associated with a conf
 * and therefore removed. if a conference is given, the dsp is expected to
 * be member of that conference.
 */
void
dsp_cmx_hardware(struct dsp_conf *conf, struct dsp *dsp)
{
	struct dsp_conf_member	*member, *nextm;
	struct dsp		*finddsp;
	int		memb = 0, i, ii, i1, i2;
	int		freeunits[8];
	u_char		freeslots[256];
	int		same_hfc = -1, same_pcm = -1, current_conf = -1,
	    all_conf = 1;

	/* dsp gets updated (no conf) */
	if (!conf) {
		if (!dsp)
			return;
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG "%s checking dsp %s\n",
			    __func__, dsp->name);
one_member:
		/* remove HFC conference if enabled */
		if (dsp->hfc_conf >= 0) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s removing %s from HFC conf %d "
				    "because dsp is split\n", __func__,
				    dsp->name, dsp->hfc_conf);
			dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_CONF_SPLIT,
			    0, 0, 0, 0);
			dsp->hfc_conf = -1;
		}
		/* process hw echo */
		if (dsp->features.pcm_banks < 1)
			return;
		if (!dsp->echo) {
			/* NO ECHO: remove PCM slot if assigned */
			if (dsp->pcm_slot_tx >= 0 || dsp->pcm_slot_rx >= 0) {
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG "%s removing %s from"
					    " PCM slot %d (TX) %d (RX) because"
					    " dsp is split (no echo)\n",
					    __func__, dsp->name,
					    dsp->pcm_slot_tx, dsp->pcm_slot_rx);
				dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_PCM_DISC,
				    0, 0, 0, 0);
				dsp->pcm_slot_tx = -1;
				dsp->pcm_bank_tx = -1;
				dsp->pcm_slot_rx = -1;
				dsp->pcm_bank_rx = -1;
			}
			return;
		}
		/* ECHO: already echo */
		if (dsp->pcm_slot_tx >= 0 && dsp->pcm_slot_rx < 0 &&
		    dsp->pcm_bank_tx == 2 && dsp->pcm_bank_rx == 2)
			return;
		/* ECHO: if slot already assigned */
		if (dsp->pcm_slot_tx >= 0) {
			dsp->pcm_slot_rx = dsp->pcm_slot_tx;
			dsp->pcm_bank_tx = 2; /* 2 means loop */
			dsp->pcm_bank_rx = 2;
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s refresh %s for echo using slot %d\n",
				    __func__, dsp->name,
				    dsp->pcm_slot_tx);
			dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_PCM_CONN,
			    dsp->pcm_slot_tx, 2, dsp->pcm_slot_rx, 2);
			return;
		}
		/* ECHO: find slot */
		dsp->pcm_slot_tx = -1;
		dsp->pcm_slot_rx = -1;
		memset(freeslots, 1, sizeof(freeslots));
		list_for_each_entry(finddsp, &dsp_ilist, list) {
			if (finddsp->features.pcm_id == dsp->features.pcm_id) {
				if (finddsp->pcm_slot_rx >= 0 &&
				    finddsp->pcm_slot_rx < sizeof(freeslots))
					freeslots[finddsp->pcm_slot_tx] = 0;
				if (finddsp->pcm_slot_tx >= 0 &&
				    finddsp->pcm_slot_tx < sizeof(freeslots))
					freeslots[finddsp->pcm_slot_rx] = 0;
			}
		}
		i = 0;
		ii = dsp->features.pcm_slots;
		while (i < ii) {
			if (freeslots[i])
				break;
			i++;
		}
		if (i == ii) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s no slot available for echo\n",
				    __func__);
			/* no more slots available */
			return;
		}
		/* assign free slot */
		dsp->pcm_slot_tx = i;
		dsp->pcm_slot_rx = i;
		dsp->pcm_bank_tx = 2; /* loop */
		dsp->pcm_bank_rx = 2;
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG
			    "%s assign echo for %s using slot %d\n",
			    __func__, dsp->name, dsp->pcm_slot_tx);
		dsp_cmx_hw_message(dsp, MISDN_CTRL_HFC_PCM_CONN,
		    dsp->pcm_slot_tx, 2, dsp->pcm_slot_rx, 2);
		return;
	}

	/* conf gets updated (all members) */
	if (dsp_debug & DEBUG_DSP_CMX)
		printk(KERN_DEBUG "%s checking conference %d\n",
		    __func__, conf->id);

	if (list_empty(&conf->mlist)) {
		printk(KERN_ERR "%s: conference whithout members\n",
		    __func__);
		return;
	}
	member = list_entry(conf->mlist.next, struct dsp_conf_member, list);
	same_hfc = member->dsp->features.hfc_id;
	same_pcm = member->dsp->features.pcm_id;
	/* check all members in our conference */
	list_for_each_entry(member, &conf->mlist, list) {
		/* check if member uses mixing */
		if (member->dsp->tx_mix) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "tx_mix is turned on\n", __func__,
				    member->dsp->name);
conf_software:
			list_for_each_entry(member, &conf->mlist, list) {
				dsp = member->dsp;
				/* remove HFC conference if enabled */
				if (dsp->hfc_conf >= 0) {
					if (dsp_debug & DEBUG_DSP_CMX)
						printk(KERN_DEBUG
						    "%s removing %s from HFC "
						    "conf %d because not "
						    "possible with hardware\n",
						    __func__,
						    dsp->name,
						    dsp->hfc_conf);
					dsp_cmx_hw_message(dsp,
					    MISDN_CTRL_HFC_CONF_SPLIT,
					    0, 0, 0, 0);
					dsp->hfc_conf = -1;
				}
				/* remove PCM slot if assigned */
				if (dsp->pcm_slot_tx >= 0 ||
				    dsp->pcm_slot_rx >= 0) {
					if (dsp_debug & DEBUG_DSP_CMX)
						printk(KERN_DEBUG "%s removing "
						    "%s from PCM slot %d (TX)"
						    " slot %d (RX) because not"
						    " possible with hardware\n",
						    __func__,
						    dsp->name,
						    dsp->pcm_slot_tx,
						    dsp->pcm_slot_rx);
					dsp_cmx_hw_message(dsp,
					    MISDN_CTRL_HFC_PCM_DISC,
					    0, 0, 0, 0);
					dsp->pcm_slot_tx = -1;
					dsp->pcm_bank_tx = -1;
					dsp->pcm_slot_rx = -1;
					dsp->pcm_bank_rx = -1;
				}
			}
			conf->hardware = 0;
			conf->software = 1;
			return;
		}
		/* check if member has echo turned on */
		if (member->dsp->echo) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "echo is turned on\n", __func__,
				    member->dsp->name);
			goto conf_software;
		}
		/* check if member has tx_mix turned on */
		if (member->dsp->tx_mix) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "tx_mix is turned on\n",
				    __func__, member->dsp->name);
			goto conf_software;
		}
		/* check if member changes volume at an not suppoted level */
		if (member->dsp->tx_volume) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "tx_volume is changed\n",
				    __func__, member->dsp->name);
			goto conf_software;
		}
		if (member->dsp->rx_volume) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "rx_volume is changed\n",
				    __func__, member->dsp->name);
			goto conf_software;
		}
		/* check if tx-data turned on */
		if (member->dsp->tx_data) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "tx_data is turned on\n",
				    __func__, member->dsp->name);
			goto conf_software;
		}
		/* check if pipeline exists */
		if (member->dsp->pipeline.inuse) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "pipeline exists\n", __func__,
				    member->dsp->name);
			goto conf_software;
		}
		/* check if encryption is enabled */
		if (member->dsp->bf_enable) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG "%s dsp %s cannot form a "
				    "conf, because encryption is enabled\n",
				    __func__, member->dsp->name);
			goto conf_software;
		}
		/* check if member is on a card with PCM support */
		if (member->dsp->features.pcm_id < 0) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "dsp has no PCM bus\n",
				    __func__, member->dsp->name);
			goto conf_software;
		}
		/* check if relations are on the same PCM bus */
		if (member->dsp->features.pcm_id != same_pcm) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s dsp %s cannot form a conf, because "
				    "dsp is on a different PCM bus than the "
				    "first dsp\n",
				    __func__, member->dsp->name);
			goto conf_software;
		}
		/* determine if members are on the same hfc chip */
		if (same_hfc != member->dsp->features.hfc_id)
			same_hfc = -1;
		/* if there are members already in a conference */
		if (current_conf < 0 && member->dsp->hfc_conf >= 0)
			current_conf = member->dsp->hfc_conf;
		/* if any member is not in a conference */
		if (member->dsp->hfc_conf < 0)
			all_conf = 0;

		memb++;
	}

	/* if no member, this is an error */
	if (memb < 1)
		return;

	/* one member */
	if (memb == 1) {
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG
			    "%s conf %d cannot form a HW conference, "
			    "because dsp is alone\n", __func__, conf->id);
		conf->hardware = 0;
		conf->software = 0;
		member = list_entry(conf->mlist.next, struct dsp_conf_member,
			list);
		dsp = member->dsp;
		goto one_member;
	}

	/*
	 * ok, now we are sure that all members are on the same pcm.
	 * now we will see if we have only two members, so we can do
	 * crossconnections, which don't have any limitations.
	 */

	/* if we have only two members */
	if (memb == 2) {
		member = list_entry(conf->mlist.next, struct dsp_conf_member,
			list);
		nextm = list_entry(member->list.next, struct dsp_conf_member,
			list);
		/* remove HFC conference if enabled */
		if (member->dsp->hfc_conf >= 0) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s removing %s from HFC conf %d because "
				    "two parties require only a PCM slot\n",
				    __func__, member->dsp->name,
				    member->dsp->hfc_conf);
			dsp_cmx_hw_message(member->dsp,
			    MISDN_CTRL_HFC_CONF_SPLIT, 0, 0, 0, 0);
			member->dsp->hfc_conf = -1;
		}
		if (nextm->dsp->hfc_conf >= 0) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s removing %s from HFC conf %d because "
				    "two parties require only a PCM slot\n",
				    __func__, nextm->dsp->name,
				    nextm->dsp->hfc_conf);
			dsp_cmx_hw_message(nextm->dsp,
			    MISDN_CTRL_HFC_CONF_SPLIT, 0, 0, 0, 0);
			nextm->dsp->hfc_conf = -1;
		}
		/* if members have two banks (and not on the same chip) */
		if (member->dsp->features.pcm_banks > 1 &&
		    nextm->dsp->features.pcm_banks > 1 &&
		    member->dsp->features.hfc_id !=
		    nextm->dsp->features.hfc_id) {
			/* if both members have same slots with crossed banks */
			if (member->dsp->pcm_slot_tx >= 0 &&
			    member->dsp->pcm_slot_rx >= 0 &&
			    nextm->dsp->pcm_slot_tx >= 0 &&
			    nextm->dsp->pcm_slot_rx >= 0 &&
			    nextm->dsp->pcm_slot_tx ==
			    member->dsp->pcm_slot_rx &&
			    nextm->dsp->pcm_slot_rx ==
			    member->dsp->pcm_slot_tx &&
			    nextm->dsp->pcm_slot_tx ==
			    member->dsp->pcm_slot_tx &&
			    member->dsp->pcm_bank_tx !=
			    member->dsp->pcm_bank_rx &&
			    nextm->dsp->pcm_bank_tx !=
			    nextm->dsp->pcm_bank_rx) {
				/* all members have same slot */
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s dsp %s & %s stay joined on "
					    "PCM slot %d bank %d (TX) bank %d "
					    "(RX) (on different chips)\n",
					    __func__,
					    member->dsp->name,
					    nextm->dsp->name,
					    member->dsp->pcm_slot_tx,
					    member->dsp->pcm_bank_tx,
					    member->dsp->pcm_bank_rx);
				conf->hardware = 0;
				conf->software = 1;
				return;
			}
			/* find a new slot */
			memset(freeslots, 1, sizeof(freeslots));
			list_for_each_entry(dsp, &dsp_ilist, list) {
				if (dsp != member->dsp &&
				    dsp != nextm->dsp &&
				    member->dsp->features.pcm_id ==
				    dsp->features.pcm_id) {
					if (dsp->pcm_slot_rx >= 0 &&
					    dsp->pcm_slot_rx <
					    sizeof(freeslots))
						freeslots[dsp->pcm_slot_tx] = 0;
					if (dsp->pcm_slot_tx >= 0 &&
					    dsp->pcm_slot_tx <
					    sizeof(freeslots))
						freeslots[dsp->pcm_slot_rx] = 0;
				}
			}
			i = 0;
			ii = member->dsp->features.pcm_slots;
			while (i < ii) {
				if (freeslots[i])
					break;
				i++;
			}
			if (i == ii) {
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s no slot available for "
					    "%s & %s\n", __func__,
					    member->dsp->name,
					    nextm->dsp->name);
				/* no more slots available */
				goto conf_software;
			}
			/* assign free slot */
			member->dsp->pcm_slot_tx = i;
			member->dsp->pcm_slot_rx = i;
			nextm->dsp->pcm_slot_tx = i;
			nextm->dsp->pcm_slot_rx = i;
			member->dsp->pcm_bank_rx = 0;
			member->dsp->pcm_bank_tx = 1;
			nextm->dsp->pcm_bank_rx = 1;
			nextm->dsp->pcm_bank_tx = 0;
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s adding %s & %s to new PCM slot %d "
				    "(TX and RX on different chips) because "
				    "both members have not same slots\n",
				    __func__,
				    member->dsp->name,
				    nextm->dsp->name,
				    member->dsp->pcm_slot_tx);
			dsp_cmx_hw_message(member->dsp, MISDN_CTRL_HFC_PCM_CONN,
			    member->dsp->pcm_slot_tx, member->dsp->pcm_bank_tx,
			    member->dsp->pcm_slot_rx, member->dsp->pcm_bank_rx);
			dsp_cmx_hw_message(nextm->dsp, MISDN_CTRL_HFC_PCM_CONN,
			    nextm->dsp->pcm_slot_tx, nextm->dsp->pcm_bank_tx,
			    nextm->dsp->pcm_slot_rx, nextm->dsp->pcm_bank_rx);
			conf->hardware = 1;
			conf->software = 0;
			return;
		/* if members have one bank (or on the same chip) */
		} else {
			/* if both members have different crossed slots */
			if (member->dsp->pcm_slot_tx >= 0 &&
			    member->dsp->pcm_slot_rx >= 0 &&
			    nextm->dsp->pcm_slot_tx >= 0 &&
			    nextm->dsp->pcm_slot_rx >= 0 &&
			    nextm->dsp->pcm_slot_tx ==
			    member->dsp->pcm_slot_rx &&
			    nextm->dsp->pcm_slot_rx ==
			    member->dsp->pcm_slot_tx &&
			    member->dsp->pcm_slot_tx !=
			    member->dsp->pcm_slot_rx &&
			    member->dsp->pcm_bank_tx == 0 &&
			    member->dsp->pcm_bank_rx == 0 &&
			    nextm->dsp->pcm_bank_tx == 0 &&
			    nextm->dsp->pcm_bank_rx == 0) {
				/* all members have same slot */
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s dsp %s & %s stay joined on PCM "
					    "slot %d (TX) %d (RX) on same chip "
					    "or one bank PCM)\n", __func__,
					    member->dsp->name,
					    nextm->dsp->name,
					    member->dsp->pcm_slot_tx,
					    member->dsp->pcm_slot_rx);
				conf->hardware = 0;
				conf->software = 1;
				return;
			}
			/* find two new slot */
			memset(freeslots, 1, sizeof(freeslots));
			list_for_each_entry(dsp, &dsp_ilist, list) {
				if (dsp != member->dsp &&
				    dsp != nextm->dsp &&
				    member->dsp->features.pcm_id ==
				    dsp->features.pcm_id) {
					if (dsp->pcm_slot_rx >= 0 &&
					    dsp->pcm_slot_rx <
					    sizeof(freeslots))
						freeslots[dsp->pcm_slot_tx] = 0;
					if (dsp->pcm_slot_tx >= 0 &&
					    dsp->pcm_slot_tx <
					    sizeof(freeslots))
						freeslots[dsp->pcm_slot_rx] = 0;
				}
			}
			i1 = 0;
			ii = member->dsp->features.pcm_slots;
			while (i1 < ii) {
				if (freeslots[i1])
					break;
				i1++;
			}
			if (i1 == ii) {
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s no slot available "
					    "for %s & %s\n", __func__,
					    member->dsp->name,
					    nextm->dsp->name);
				/* no more slots available */
				goto conf_software;
			}
			i2 = i1+1;
			while (i2 < ii) {
				if (freeslots[i2])
					break;
				i2++;
			}
			if (i2 == ii) {
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s no slot available "
					    "for %s & %s\n",
					    __func__,
					    member->dsp->name,
					    nextm->dsp->name);
				/* no more slots available */
				goto conf_software;
			}
			/* assign free slots */
			member->dsp->pcm_slot_tx = i1;
			member->dsp->pcm_slot_rx = i2;
			nextm->dsp->pcm_slot_tx = i2;
			nextm->dsp->pcm_slot_rx = i1;
			member->dsp->pcm_bank_rx = 0;
			member->dsp->pcm_bank_tx = 0;
			nextm->dsp->pcm_bank_rx = 0;
			nextm->dsp->pcm_bank_tx = 0;
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s adding %s & %s to new PCM slot %d "
				    "(TX) %d (RX) on same chip or one bank "
				    "PCM, because both members have not "
				    "crossed slots\n", __func__,
				    member->dsp->name,
				    nextm->dsp->name,
				    member->dsp->pcm_slot_tx,
				    member->dsp->pcm_slot_rx);
			dsp_cmx_hw_message(member->dsp, MISDN_CTRL_HFC_PCM_CONN,
			    member->dsp->pcm_slot_tx, member->dsp->pcm_bank_tx,
			    member->dsp->pcm_slot_rx, member->dsp->pcm_bank_rx);
			dsp_cmx_hw_message(nextm->dsp, MISDN_CTRL_HFC_PCM_CONN,
			    nextm->dsp->pcm_slot_tx, nextm->dsp->pcm_bank_tx,
			    nextm->dsp->pcm_slot_rx, nextm->dsp->pcm_bank_rx);
			conf->hardware = 1;
			conf->software = 0;
			return;
		}
	}

	/*
	 * if we have more than two, we may check if we have a conference
	 * unit available on the chip. also all members must be on the same
	 */

	/* if not the same HFC chip */
	if (same_hfc < 0) {
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG
			    "%s conference %d cannot be formed, because "
			    "members are on different chips or not "
			    "on HFC chip\n",
			    __func__, conf->id);
		goto conf_software;
	}

	/* for more than two members.. */

	/* in case of hdlc, we change to software */
	if (dsp->hdlc)
		goto conf_software;

	/* if all members already have the same conference */
	if (all_conf)
		return;

	/*
	 * if there is an existing conference, but not all members have joined
	 */
	if (current_conf >= 0) {
join_members:
		list_for_each_entry(member, &conf->mlist, list) {
			/* join to current conference */
			if (member->dsp->hfc_conf == current_conf)
				continue;
			/* get a free timeslot first */
			memset(freeslots, 1, sizeof(freeslots));
			list_for_each_entry(dsp, &dsp_ilist, list) {
				/*
				 * not checking current member, because
				 * slot will be overwritten.
				 */
				if (
				    dsp != member->dsp &&
				/* dsp must be on the same PCM */
				    member->dsp->features.pcm_id ==
				    dsp->features.pcm_id) {
					/* dsp must be on a slot */
					if (dsp->pcm_slot_tx >= 0 &&
					    dsp->pcm_slot_tx <
					    sizeof(freeslots))
						freeslots[dsp->pcm_slot_tx] = 0;
					if (dsp->pcm_slot_rx >= 0 &&
					    dsp->pcm_slot_rx <
					    sizeof(freeslots))
						freeslots[dsp->pcm_slot_rx] = 0;
				}
			}
			i = 0;
			ii = member->dsp->features.pcm_slots;
			while (i < ii) {
				if (freeslots[i])
					break;
				i++;
			}
			if (i == ii) {
				/* no more slots available */
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s conference %d cannot be formed,"
					    " because no slot free\n",
					    __func__, conf->id);
				goto conf_software;
			}
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "%s changing dsp %s to HW conference "
				    "%d slot %d\n", __func__,
				    member->dsp->name, current_conf, i);
			/* assign free slot & set PCM & join conf */
			member->dsp->pcm_slot_tx = i;
			member->dsp->pcm_slot_rx = i;
			member->dsp->pcm_bank_tx = 2; /* loop */
			member->dsp->pcm_bank_rx = 2;
			member->dsp->hfc_conf = current_conf;
			dsp_cmx_hw_message(member->dsp, MISDN_CTRL_HFC_PCM_CONN,
			    i, 2, i, 2);
			dsp_cmx_hw_message(member->dsp,
			    MISDN_CTRL_HFC_CONF_JOIN, current_conf, 0, 0, 0);
		}
		return;
	}

	/*
	 * no member is in a conference yet, so we find a free one
	 */
	memset(freeunits, 1, sizeof(freeunits));
	list_for_each_entry(dsp, &dsp_ilist, list) {
		/* dsp must be on the same chip */
		if (dsp->features.hfc_id == same_hfc &&
		    /* dsp must have joined a HW conference */
		    dsp->hfc_conf >= 0 &&
		    /* slot must be within range */
		    dsp->hfc_conf < 8)
			freeunits[dsp->hfc_conf] = 0;
	}
	i = 0;
	ii = 8;
	while (i < ii) {
		if (freeunits[i])
			break;
		i++;
	}
	if (i == ii) {
		/* no more conferences available */
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG
			    "%s conference %d cannot be formed, because "
			    "no conference number free\n",
			    __func__, conf->id);
		goto conf_software;
	}
	/* join all members */
	current_conf = i;
	goto join_members;
}


/*
 * conf_id != 0: join or change conference
 * conf_id == 0: split from conference if not already
 */
int
dsp_cmx_conf(struct dsp *dsp, u32 conf_id)
{
	int err;
	struct dsp_conf *conf;
	struct dsp_conf_member	*member;

	/* if conference doesn't change */
	if (dsp->conf_id == conf_id)
		return 0;

	/* first remove us from current conf */
	if (dsp->conf_id) {
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG "removing us from conference %d\n",
				dsp->conf->id);
		/* remove us from conf */
		conf = dsp->conf;
		err = dsp_cmx_del_conf_member(dsp);
		if (err)
			return err;
		dsp->conf_id = 0;

		/* update hardware */
		dsp_cmx_hardware(NULL, dsp);

		/* conf now empty? */
		if (list_empty(&conf->mlist)) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "conference is empty, so we remove it.\n");
			err = dsp_cmx_del_conf(conf);
			if (err)
				return err;
		} else {
			/* update members left on conf */
			dsp_cmx_hardware(conf, NULL);
		}
	}

	/* if split */
	if (!conf_id)
		return 0;

	/* now add us to conf */
	if (dsp_debug & DEBUG_DSP_CMX)
		printk(KERN_DEBUG "searching conference %d\n",
			conf_id);
	conf = dsp_cmx_search_conf(conf_id);
	if (!conf) {
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG
			    "conference doesn't exist yet, creating.\n");
		/* the conference doesn't exist, so we create */
		conf = dsp_cmx_new_conf(conf_id);
		if (!conf)
			return -EINVAL;
	} else if (!list_empty(&conf->mlist)) {
		member = list_entry(conf->mlist.next, struct dsp_conf_member,
			list);
		if (dsp->hdlc && !member->dsp->hdlc) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "cannot join transparent conference.\n");
			return -EINVAL;
		}
		if (!dsp->hdlc && member->dsp->hdlc) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "cannot join hdlc conference.\n");
			return -EINVAL;
		}
	}
	/* add conference member */
	err = dsp_cmx_add_conf_member(dsp, conf);
	if (err)
		return err;
	dsp->conf_id = conf_id;

	/* if we are alone, we do nothing! */
	if (list_empty(&conf->mlist)) {
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG
			    "we are alone in this conference, so exit.\n");
		/* update hardware */
		dsp_cmx_hardware(NULL, dsp);
		return 0;
	}

	/* update members on conf */
	dsp_cmx_hardware(conf, NULL);

	return 0;
}


/*
 * audio data is received from card
 */
void
dsp_cmx_receive(struct dsp *dsp, struct sk_buff *skb)
{
	u8 *d, *p;
	int len = skb->len;
	struct mISDNhead *hh = mISDN_HEAD_P(skb);
	int w, i, ii;

	/* check if we have sompen */
	if (len < 1)
		return;

	/* half of the buffer should be larger than maximum packet size */
	if (len >= CMX_BUFF_HALF) {
		printk(KERN_ERR
		    "%s line %d: packet from card is too large (%d bytes). "
		    "please make card send smaller packets OR increase "
		    "CMX_BUFF_SIZE\n", __FILE__, __LINE__, len);
		return;
	}

	/*
	 * initialize pointers if not already -
	 * also add delay if requested by PH_SIGNAL
	 */
	if (dsp->rx_init) {
		dsp->rx_init = 0;
		if (dsp->features.unordered) {
			dsp->rx_R = (hh->id & CMX_BUFF_MASK);
			dsp->rx_W = (dsp->rx_R + dsp->cmx_delay)
				& CMX_BUFF_MASK;
		} else {
			dsp->rx_R = 0;
			dsp->rx_W = dsp->cmx_delay;
		}
	}
	/* if frame contains time code, write directly */
	if (dsp->features.unordered) {
		dsp->rx_W = (hh->id & CMX_BUFF_MASK);
		/* printk(KERN_DEBUG "%s %08x\n", dsp->name, hh->id); */
	}
	/*
	 * if we underrun (or maybe overrun),
	 * we set our new read pointer, and write silence to buffer
	 */
	if (((dsp->rx_W-dsp->rx_R) & CMX_BUFF_MASK) >= CMX_BUFF_HALF) {
		if (dsp_debug & DEBUG_DSP_CMX)
			printk(KERN_DEBUG
			    "cmx_receive(dsp=%lx): UNDERRUN (or overrun the "
			    "maximum delay), adjusting read pointer! "
			    "(inst %s)\n", (u_long)dsp, dsp->name);
		/* flush buffer */
		if (dsp->features.unordered) {
			dsp->rx_R = (hh->id & CMX_BUFF_MASK);
			dsp->rx_W = (dsp->rx_R + dsp->cmx_delay)
				& CMX_BUFF_MASK;
		} else {
			dsp->rx_R = 0;
			dsp->rx_W = dsp->cmx_delay;
		}
		memset(dsp->rx_buff, dsp_silence, sizeof(dsp->rx_buff));
	}
	/* if we have reached double delay, jump back to middle */
	if (dsp->cmx_delay)
		if (((dsp->rx_W - dsp->rx_R) & CMX_BUFF_MASK) >=
		    (dsp->cmx_delay << 1)) {
			if (dsp_debug & DEBUG_DSP_CMX)
				printk(KERN_DEBUG
				    "cmx_receive(dsp=%lx): OVERRUN (because "
				    "twice the delay is reached), adjusting "
				    "read pointer! (inst %s)\n",
				    (u_long)dsp, dsp->name);
		/* flush buffer */
		if (dsp->features.unordered) {
			dsp->rx_R = (hh->id & CMX_BUFF_MASK);
			dsp->rx_W = (dsp->rx_R + dsp->cmx_delay)
				& CMX_BUFF_MASK;
		} else {
			dsp->rx_R = 0;
			dsp->rx_W = dsp->cmx_delay;
		}
		memset(dsp->rx_buff, dsp_silence, sizeof(dsp->rx_buff));
	}

	/* show where to write */
#ifdef CMX_DEBUG
	printk(KERN_DEBUG
	    "cmx_receive(dsp=%lx): rx_R(dsp)=%05x rx_W(dsp)=%05x len=%d %s\n",
	    (u_long)dsp, dsp->rx_R, dsp->rx_W, len, dsp->name);
#endif

	/* write data into rx_buffer */
	p = skb->data;
	d = dsp->rx_buff;
	w = dsp->rx_W;
	i = 0;
	ii = len;
	while (i < ii) {
		d[w++ & CMX_BUFF_MASK] = *p++;
		i++;
	}

	/* increase write-pointer */
	dsp->rx_W = ((dsp->rx_W+len) & CMX_BUFF_MASK);
}


/*
 * send (mixed) audio data to card and control jitter
 */
static void
dsp_cmx_send_member(struct dsp *dsp, int len, s32 *c, int members)
{
	struct dsp_conf *conf = dsp->conf;
	struct dsp *member, *other;
	register s32 sample;
	u8 *d, *p, *q, *o_q;
	struct sk_buff *nskb, *txskb;
	int r, rr, t, tt, o_r, o_rr;
	int preload = 0;
	struct mISDNhead *hh, *thh;

	/* don't process if: */
	if (!dsp->b_active) { /* if not active */
		dsp->last_tx = 0;
		return;
	}
	if (dsp->pcm_slot_tx >= 0 && /* connected to pcm slot */
	    dsp->tx_R == dsp->tx_W && /* AND no tx-data */
	    !(dsp->tone.tone && dsp->tone.software)) { /* AND not soft tones */
		dsp->last_tx = 0;
		return;
	}

#ifdef CMX_DEBUG
	printk(KERN_DEBUG
	    "SEND members=%d dsp=%s, conf=%p, rx_R=%05x rx_W=%05x\n",
	    members, dsp->name, conf, dsp->rx_R, dsp->rx_W);
#endif

	/* preload if we have delay set */
	if (dsp->cmx_delay && !dsp->last_tx) {
		preload = len;
		if (preload < 128)
			preload = 128;
	}

	/* PREPARE RESULT */
	nskb = mI_alloc_skb(len + preload, GFP_ATOMIC);
	if (!nskb) {
		printk(KERN_ERR
		    "FATAL ERROR in mISDN_dsp.o: cannot alloc %d bytes\n",
		    len + preload);
		return;
	}
	hh = mISDN_HEAD_P(nskb);
	hh->prim = PH_DATA_REQ;
	hh->id = 0;
	dsp->last_tx = 1;

	/* set pointers, indexes and stuff */
	member = dsp;
	p = dsp->tx_buff; /* transmit data */
	q = dsp->rx_buff; /* received data */
	d = skb_put(nskb, preload + len); /* result */
	t = dsp->tx_R; /* tx-pointers */
	tt = dsp->tx_W;
	r = dsp->rx_R; /* rx-pointers */
	rr = (r + len) & CMX_BUFF_MASK;

	/* preload with silence, if required */
	if (preload) {
		memset(d, dsp_silence, preload);
		d += preload;
	}

	/* PROCESS TONES/TX-DATA ONLY */
	if (dsp->tone.tone && dsp->tone.software) {
		/* -> copy tone */
		dsp_tone_copy(dsp, d, len);
		dsp->tx_R = 0; /* clear tx buffer */
		dsp->tx_W = 0;
		goto send_packet;
	}
	/* if we have tx-data but do not use mixing */
	if (!dsp->tx_mix && t != tt) {
		/* -> send tx-data and continue when not enough */
#ifdef CMX_TX_DEBUG
	sprintf(debugbuf, "TX sending (%04x-%04x)%p: ", t, tt, p);
#endif
		while (r != rr && t != tt) {
#ifdef CMX_TX_DEBUG
			if (strlen(debugbuf) < 48)
			    sprintf(debugbuf+strlen(debugbuf), " %02x", p[t]);
#endif
			*d++ = p[t]; /* write tx_buff */
			t = (t+1) & CMX_BUFF_MASK;
			r = (r+1) & CMX_BUFF_MASK;
		}
		if (r == rr) {
			dsp->tx_R = t;
#ifdef CMX_TX_DEBUG
	printk(KERN_DEBUG "%s\n", debugbuf);
#endif
			goto send_packet;
		}
	}
#ifdef CMX_TX_DEBUG
	printk(KERN_DEBUG "%s\n", debugbuf);
#endif

	/* PROCESS DATA (one member / no conf) */
	if (!conf || members <= 1) {
		/* -> if echo is NOT enabled */
		if (!dsp->echo) {
			/* -> send tx-data if available or use 0-volume */
			while (r != rr && t != tt) {
				*d++ = p[t]; /* write tx_buff */
				t = (t+1) & CMX_BUFF_MASK;
				r = (r+1) & CMX_BUFF_MASK;
			}
			if (r != rr)
				memset(d, dsp_silence, (rr-r)&CMX_BUFF_MASK);
		/* -> if echo is enabled */
		} else {
			/*
			 * -> mix tx-data with echo if available,
			 * or use echo only
			 */
			while (r != rr && t != tt) {
				*d++ = dsp_audio_mix_law[(p[t]<<8)|q[r]];
				t = (t+1) & CMX_BUFF_MASK;
				r = (r+1) & CMX_BUFF_MASK;
			}
			while (r != rr) {
				*d++ = q[r]; /* echo */
				r = (r+1) & CMX_BUFF_MASK;
			}
		}
		dsp->tx_R = t;
		goto send_packet;
	}
	/* PROCESS DATA (two members) */
#ifdef CMX_CONF_DEBUG
	if (0) {
#else
	if (members == 2) {
#endif
		/* "other" becomes other party */
		other = (list_entry(conf->mlist.next,
		    struct dsp_conf_member, list))->dsp;
		if (other == member)
			other = (list_entry(conf->mlist.prev,
			    struct dsp_conf_member, list))->dsp;
		o_q = other->rx_buff; /* received data */
		o_rr = (other->rx_R + len) & CMX_BUFF_MASK;
			/* end of rx-pointer */
		o_r = (o_rr - rr + r) & CMX_BUFF_MASK;
			/* start rx-pointer at current read position*/
		/* -> if echo is NOT enabled */
		if (!dsp->echo) {
			/*
			 * -> copy other member's rx-data,
			 * if tx-data is available, mix
			 */
			while (o_r != o_rr && t != tt) {
				*d++ = dsp_audio_mix_law[(p[t]<<8)|o_q[o_r]];
				t = (t+1) & CMX_BUFF_MASK;
				o_r = (o_r+1) & CMX_BUFF_MASK;
			}
			while (o_r != o_rr) {
				*d++ = o_q[o_r];
				o_r = (o_r+1) & CMX_BUFF_MASK;
			}
		/* -> if echo is enabled */
		} else {
			/*
			 * -> mix other member's rx-data with echo,
			 * if tx-data is available, mix
			 */
			while (r != rr && t != tt) {
				sample = dsp_audio_law_to_s32[p[t]] +
				    dsp_audio_law_to_s32[q[r]] +
				    dsp_audio_law_to_s32[o_q[o_r]];
				if (sample < -32768)
					sample = -32768;
				else if (sample > 32767)
					sample = 32767;
				*d++ = dsp_audio_s16_to_law[sample & 0xffff];
				    /* tx-data + rx_data + echo */
				t = (t+1) & CMX_BUFF_MASK;
				r = (r+1) & CMX_BUFF_MASK;
				o_r = (o_r+1) & CMX_BUFF_MASK;
			}
			while (r != rr) {
				*d++ = dsp_audio_mix_law[(q[r]<<8)|o_q[o_r]];
				r = (r+1) & CMX_BUFF_MASK;
				o_r = (o_r+1) & CMX_BUFF_MASK;
			}
		}
		dsp->tx_R = t;
		goto send_packet;
	}
#ifdef DSP_NEVER_DEFINED
	}
#endif
	/* PROCESS DATA (three or more members) */
	/* -> if echo is NOT enabled */
	if (!dsp->echo) {
		/*
		 * -> substract rx-data from conf-data,
		 * if tx-data is available, mix
		 */
		while (r != rr && t != tt) {
			sample = dsp_audio_law_to_s32[p[t]] + *c++ -
			    dsp_audio_law_to_s32[q[r]];
			if (sample < -32768)
				sample = -32768;
			else if (sample > 32767)
				sample = 32767;
			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
			    /* conf-rx+tx */
			r = (r+1) & CMX_BUFF_MASK;
			t = (t+1) & CMX_BUFF_MASK;
		}
		while (r != rr) {
			sample = *c++ - dsp_audio_law_to_s32[q[r]];
			if (sample < -32768)
				sample = -32768;
			else if (sample > 32767)
				sample = 32767;
			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
			    /* conf-rx */
			r = (r+1) & CMX_BUFF_MASK;
		}
	/* -> if echo is enabled */
	} else {
		/*
		 * -> encode conf-data, if tx-data
		 * is available, mix
		 */
		while (r != rr && t != tt) {
			sample = dsp_audio_law_to_s32[p[t]] + *c++;
			if (sample < -32768)
				sample = -32768;
			else if (sample > 32767)
				sample = 32767;
			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
			    /* conf(echo)+tx */
			t = (t+1) & CMX_BUFF_MASK;
			r = (r+1) & CMX_BUFF_MASK;
		}
		while (r != rr) {
			sample = *c++;
			if (sample < -32768)
				sample = -32768;
			else if (sample > 32767)
				sample = 32767;
			*d++ = dsp_audio_s16_to_law[sample & 0xffff];
			    /* conf(echo) */
			r = (r+1) & CMX_BUFF_MASK;
		}
	}
	dsp->tx_R = t;
	goto send_packet;

send_packet:
	/*
	 * send tx-data if enabled - don't filter,
	 * becuase we want what we send, not what we filtered
	 */
	if (dsp->tx_data) {
		/* PREPARE RESULT */
		txskb = mI_alloc_skb(len, GFP_ATOMIC);
		if (!txskb) {
			printk(KERN_ERR
			    "FATAL ERROR in mISDN_dsp.o: "
			    "cannot alloc %d bytes\n", len);
		} else {
			thh = mISDN_HEAD_P(txskb);
			thh->prim = DL_DATA_REQ;
			thh->id = 0;
			memcpy(skb_put(txskb, len), nskb->data+preload, len);
			/* queue (trigger later) */
			skb_queue_tail(&dsp->sendq, txskb);
		}
	}
	/* adjust volume */
	if (dsp->tx_volume)
		dsp_change_volume(nskb, dsp->tx_volume);
	/* pipeline */
	if (dsp->pipeline.inuse)
		dsp_pipeline_process_tx(&dsp->pipeline, nskb->data, nskb->len);
	/* crypt */
	if (dsp->bf_enable)
		dsp_bf_encrypt(dsp, nskb->data, nskb->len);
	/* queue and trigger */
	skb_queue_tail(&dsp->sendq, nskb);
	schedule_work(&dsp->workq);
}

u32	samplecount;
struct timer_list dsp_spl_tl;
u32	dsp_spl_jiffies; /* calculate the next time to fire */
u32	dsp_start_jiffies; /* jiffies at the time, the calculation begins */
struct timeval dsp_start_tv; /* time at start of calculation */

void
dsp_cmx_send(void *arg)
{
	struct dsp_conf *conf;
	struct dsp_conf_member *member;
	struct dsp *dsp;
	int mustmix, members;
	s32 mixbuffer[MAX_POLL+100], *c;
	u8 *p, *q;
	int r, rr;
	int jittercheck = 0, delay, i;
	u_long flags;
	struct timeval tv;
	u32 elapsed;
	s16 length;

	/* lock */
	spin_lock_irqsave(&dsp_lock, flags);

	if (!dsp_start_tv.tv_sec) {
		do_gettimeofday(&dsp_start_tv);
		length = dsp_poll;
	} else {
		do_gettimeofday(&tv);
		elapsed = ((tv.tv_sec - dsp_start_tv.tv_sec) * 8000)
		    + ((s32)(tv.tv_usec / 125) - (dsp_start_tv.tv_usec / 125));
		dsp_start_tv.tv_sec = tv.tv_sec;
		dsp_start_tv.tv_usec = tv.tv_usec;
		length = elapsed;
	}
	if (length > MAX_POLL + 100)
		length = MAX_POLL + 100;
/* printk(KERN_DEBUG "len=%d dsp_count=0x%x.%04x dsp_poll_diff=0x%x.%04x\n",
 length, dsp_count >> 16, dsp_count & 0xffff, dsp_poll_diff >> 16,
 dsp_poll_diff & 0xffff);
 */

	/*
	 * check if jitter needs to be checked
	 * (this is about every second = 8192 samples)
	 */
	samplecount += length;
	if ((samplecount & 8191) < length)
		jittercheck = 1;

	/* loop all members that do not require conference mixing */
	list_for_each_entry(dsp, &dsp_ilist, list) {
		if (dsp->hdlc)
			continue;
		conf = dsp->conf;
		mustmix = 0;
		members = 0;
		if (conf) {
			members = count_list_member(&conf->mlist);
#ifdef CMX_CONF_DEBUG
			if (conf->software && members > 1)
#else
			if (conf->software && members > 2)
#endif
				mustmix = 1;
		}

		/* transmission required */
		if (!mustmix) {
			dsp_cmx_send_member(dsp, length, mixbuffer, members);

			/*
			 * unused mixbuffer is given to prevent a
			 * potential null-pointer-bug
			 */
		}
	}

	/* loop all members that require conference mixing */
	list_for_each_entry(conf, &conf_ilist, list) {
		/* count members and check hardware */
		members = count_list_member(&conf->mlist);
#ifdef CMX_CONF_DEBUG
		if (conf->software && members > 1) {
#else
		if (conf->software && members > 2) {
#endif
			/* check for hdlc conf */
			member = list_entry(conf->mlist.next,
				struct dsp_conf_member, list);
			if (member->dsp->hdlc)
				continue;
			/* mix all data */
			memset(mixbuffer, 0, length*sizeof(s32));
			list_for_each_entry(member, &conf->mlist, list) {
				dsp = member->dsp;
				/* get range of data to mix */
				c = mixbuffer;
				q = dsp->rx_buff;
				r = dsp->rx_R;
				rr = (r + length) & CMX_BUFF_MASK;
				/* add member's data */
				while (r != rr) {
					*c++ += dsp_audio_law_to_s32[q[r]];
					r = (r+1) & CMX_BUFF_MASK;
				}
			}

			/* process each member */
			list_for_each_entry(member, &conf->mlist, list) {
				/* transmission */
				dsp_cmx_send_member(member->dsp, length,
				    mixbuffer, members);
			}
		}
	}

	/* delete rx-data, increment buffers, change pointers */
	list_for_each_entry(dsp, &dsp_ilist, list) {
		if (dsp->hdlc)
			continue;
		p = dsp->rx_buff;
		q = dsp->tx_buff;
		r = dsp->rx_R;
		/* move receive pointer when receiving */
		if (!dsp->rx_is_off) {
			rr = (r + length) & CMX_BUFF_MASK;
			/* delete rx-data */
			while (r != rr) {
				p[r] = dsp_silence;
				r = (r+1) & CMX_BUFF_MASK;
			}
			/* increment rx-buffer pointer */
			dsp->rx_R = r; /* write incremented read pointer */
		}

		/* check current rx_delay */
		delay = (dsp->rx_W-dsp->rx_R) & CMX_BUFF_MASK;
		if (delay >= CMX_BUFF_HALF)
			delay = 0; /* will be the delay before next write */
		/* check for lower delay */
		if (delay < dsp->rx_delay[0])
			dsp->rx_delay[0] = delay;
		/* check current tx_delay */
		delay = (dsp->tx_W-dsp->tx_R) & CMX_BUFF_MASK;
		if (delay >= CMX_BUFF_HALF)
			delay = 0; /* will be the delay before next write */
		/* check for lower delay */
		if (delay < dsp->tx_delay[0])
			dsp->tx_delay[0] = delay;
		if (jittercheck) {
			/* find the lowest of all rx_delays */
			delay = dsp->rx_delay[0];
			i = 1;
			while (i < MAX_SECONDS_JITTER_CHECK) {
				if (delay > dsp->rx_delay[i])
					delay = dsp->rx_delay[i];
				i++;
			}
			/*
			 * remove rx_delay only if we have delay AND we
			 * have not preset cmx_delay
			 */
			if (delay && !dsp->cmx_delay) {
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s lowest rx_delay of %d bytes for"
					    " dsp %s are now removed.\n",
					    __func__, delay,
					    dsp->name);
				r = dsp->rx_R;
				rr = (r + delay) & CMX_BUFF_MASK;
				/* delete rx-data */
				while (r != rr) {
					p[r] = dsp_silence;
					r = (r+1) & CMX_BUFF_MASK;
				}
				/* increment rx-buffer pointer */
				dsp->rx_R = r;
				    /* write incremented read pointer */
			}
			/* find the lowest of all tx_delays */
			delay = dsp->tx_delay[0];
			i = 1;
			while (i < MAX_SECONDS_JITTER_CHECK) {
				if (delay > dsp->tx_delay[i])
					delay = dsp->tx_delay[i];
				i++;
			}
			/*
			 * remove delay only if we have delay AND we
			 * have enabled tx_dejitter
			 */
			if (delay && dsp->tx_dejitter) {
				if (dsp_debug & DEBUG_DSP_CMX)
					printk(KERN_DEBUG
					    "%s lowest tx_delay of %d bytes for"
					    " dsp %s are now removed.\n",
					    __func__, delay,
					    dsp->name);
				r = dsp->tx_R;
				rr = (r + delay) & CMX_BUFF_MASK;
				/* delete tx-data */
				while (r != rr) {
					q[r] = dsp_silence;
					r = (r+1) & CMX_BUFF_MASK;
				}
				/* increment rx-buffer pointer */
				dsp->tx_R = r;
				    /* write incremented read pointer */
			}
			/* scroll up delays */
			i = MAX_SECONDS_JITTER_CHECK - 1;
			while (i) {
				dsp->rx_delay[i] = dsp->rx_delay[i-1];
				dsp->tx_delay[i] = dsp->tx_delay[i-1];
				i--;
			}
			dsp->tx_delay[0] = CMX_BUFF_HALF; /* (infinite) delay */
			dsp->rx_delay[0] = CMX_BUFF_HALF; /* (infinite) delay */
		}
	}

	/* if next event would be in the past ... */
	if ((s32)(dsp_spl_jiffies+dsp_tics-jiffies) <= 0)
		dsp_spl_jiffies = jiffies + 1;
	else
		dsp_spl_jiffies += dsp_tics;

	dsp_spl_tl.expires = dsp_spl_jiffies;
	add_timer(&dsp_spl_tl);

	/* unlock */
	spin_unlock_irqrestore(&dsp_lock, flags);
}

/*
 * audio data is transmitted from upper layer to the dsp
 */
void
dsp_cmx_transmit(struct dsp *dsp, struct sk_buff *skb)
{
	u_int w, ww;
	u8 *d, *p;
	int space; /* todo: , l = skb->len; */
#ifdef CMX_TX_DEBUG
	char debugbuf[256] = "";
#endif

	/* check if there is enough space, and then copy */
	w = dsp->tx_W;
	ww = dsp->tx_R;
	p = dsp->tx_buff;
	d = skb->data;
	space = ww-w;
	if (space <= 0)
		space += CMX_BUFF_SIZE;
	/* write-pointer should not overrun nor reach read pointer */
	if (space-1 < skb->len)
		/* write to the space we have left */
		ww = (ww - 1) & CMX_BUFF_MASK;
	else
		/* write until all byte are copied */
		ww = (w + skb->len) & CMX_BUFF_MASK;
	dsp->tx_W = ww;

	/* show current buffer */
#ifdef CMX_DEBUG
	printk(KERN_DEBUG
	    "cmx_transmit(dsp=%lx) %d bytes to 0x%x-0x%x. %s\n",
	    (u_long)dsp, (ww-w)&CMX_BUFF_MASK, w, ww, dsp->name);
#endif

	/* copy transmit data to tx-buffer */
#ifdef CMX_TX_DEBUG
	sprintf(debugbuf, "TX getting (%04x-%04x)%p: ", w, ww, p);
#endif
	while (w != ww) {
#ifdef CMX_TX_DEBUG
		if (strlen(debugbuf) < 48)
			sprintf(debugbuf+strlen(debugbuf), " %02x", *d);
#endif
		p[w] = *d++;
		w = (w+1) & CMX_BUFF_MASK;
	}
#ifdef CMX_TX_DEBUG
	printk(KERN_DEBUG "%s\n", debugbuf);
#endif

}

/*
 * hdlc data is received from card and sent to all members.
 */
void
dsp_cmx_hdlc(struct dsp *dsp, struct sk_buff *skb)
{
	struct sk_buff *nskb = NULL;
	struct dsp_conf_member *member;
	struct mISDNhead *hh;

	/* not if not active */
	if (!dsp->b_active)
		return;

	/* check if we have sompen */
	if (skb->len < 1)
		return;

	/* no conf */
	if (!dsp->conf) {
		/* in case of hardware (echo) */
		if (dsp->pcm_slot_tx >= 0)
			return;
		if (dsp->echo)
			nskb = skb_clone(skb, GFP_ATOMIC);
			if (nskb) {
				hh = mISDN_HEAD_P(nskb);
				hh->prim = PH_DATA_REQ;
				hh->id = 0;
				skb_queue_tail(&dsp->sendq, nskb);
				schedule_work(&dsp->workq);
			}
		return;
	}
	/* in case of hardware conference */
	if (dsp->conf->hardware)
		return;
	list_for_each_entry(member, &dsp->conf->mlist, list) {
		if (dsp->echo || member->dsp != dsp) {
			nskb = skb_clone(skb, GFP_ATOMIC);
			if (nskb) {
				hh = mISDN_HEAD_P(nskb);
				hh->prim = PH_DATA_REQ;
				hh->id = 0;
				skb_queue_tail(&member->dsp->sendq, nskb);
				schedule_work(&member->dsp->workq);
			}
		}
	}
}