summaryrefslogtreecommitdiff
path: root/sound/usb/mixer.c
blob: 6cd4ff09c5ee60566aae77191fbd73960aa2a79a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *   (Tentative) USB Audio Driver for ALSA
 *
 *   Mixer control part
 *
 *   Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
 *
 *   Many codes borrowed from audio.c by
 *	    Alan Cox (alan@lxorguk.ukuu.org.uk)
 *	    Thomas Sailer (sailer@ife.ee.ethz.ch)
 */

/*
 * TODOs, for both the mixer and the streaming interfaces:
 *
 *  - support for UAC2 effect units
 *  - support for graphical equalizers
 *  - RANGE and MEM set commands (UAC2)
 *  - RANGE and MEM interrupt dispatchers (UAC2)
 *  - audio channel clustering (UAC2)
 *  - audio sample rate converter units (UAC2)
 *  - proper handling of clock multipliers (UAC2)
 *  - dispatch clock change notifications (UAC2)
 *  	- stop PCM streams which use a clock that became invalid
 *  	- stop PCM streams which use a clock selector that has changed
 *  	- parse available sample rates again when clock sources changed
 */

#include <linux/bitops.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/log2.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>
#include <linux/usb/audio-v3.h>

#include <sound/core.h>
#include <sound/control.h>
#include <sound/hwdep.h>
#include <sound/info.h>
#include <sound/tlv.h>

#include "usbaudio.h"
#include "mixer.h"
#include "helper.h"
#include "mixer_quirks.h"
#include "power.h"

#define MAX_ID_ELEMS	256

struct usb_audio_term {
	int id;
	int type;
	int channels;
	unsigned int chconfig;
	int name;
};

struct usbmix_name_map;

struct mixer_build {
	struct snd_usb_audio *chip;
	struct usb_mixer_interface *mixer;
	unsigned char *buffer;
	unsigned int buflen;
	DECLARE_BITMAP(unitbitmap, MAX_ID_ELEMS);
	DECLARE_BITMAP(termbitmap, MAX_ID_ELEMS);
	struct usb_audio_term oterm;
	const struct usbmix_name_map *map;
	const struct usbmix_selector_map *selector_map;
};

/*E-mu 0202/0404/0204 eXtension Unit(XU) control*/
enum {
	USB_XU_CLOCK_RATE 		= 0xe301,
	USB_XU_CLOCK_SOURCE		= 0xe302,
	USB_XU_DIGITAL_IO_STATUS	= 0xe303,
	USB_XU_DEVICE_OPTIONS		= 0xe304,
	USB_XU_DIRECT_MONITORING	= 0xe305,
	USB_XU_METERING			= 0xe306
};
enum {
	USB_XU_CLOCK_SOURCE_SELECTOR = 0x02,	/* clock source*/
	USB_XU_CLOCK_RATE_SELECTOR = 0x03,	/* clock rate */
	USB_XU_DIGITAL_FORMAT_SELECTOR = 0x01,	/* the spdif format */
	USB_XU_SOFT_LIMIT_SELECTOR = 0x03	/* soft limiter */
};

/*
 * manual mapping of mixer names
 * if the mixer topology is too complicated and the parsed names are
 * ambiguous, add the entries in usbmixer_maps.c.
 */
#include "mixer_maps.c"

static const struct usbmix_name_map *
find_map(const struct usbmix_name_map *p, int unitid, int control)
{
	if (!p)
		return NULL;

	for (; p->id; p++) {
		if (p->id == unitid &&
		    (!control || !p->control || control == p->control))
			return p;
	}
	return NULL;
}

/* get the mapped name if the unit matches */
static int
check_mapped_name(const struct usbmix_name_map *p, char *buf, int buflen)
{
	if (!p || !p->name)
		return 0;

	buflen--;
	return strlcpy(buf, p->name, buflen);
}

/* ignore the error value if ignore_ctl_error flag is set */
#define filter_error(cval, err) \
	((cval)->head.mixer->ignore_ctl_error ? 0 : (err))

/* check whether the control should be ignored */
static inline int
check_ignored_ctl(const struct usbmix_name_map *p)
{
	if (!p || p->name || p->dB)
		return 0;
	return 1;
}

/* dB mapping */
static inline void check_mapped_dB(const struct usbmix_name_map *p,
				   struct usb_mixer_elem_info *cval)
{
	if (p && p->dB) {
		cval->dBmin = p->dB->min;
		cval->dBmax = p->dB->max;
		cval->initialized = 1;
	}
}

/* get the mapped selector source name */
static int check_mapped_selector_name(struct mixer_build *state, int unitid,
				      int index, char *buf, int buflen)
{
	const struct usbmix_selector_map *p;

	if (!state->selector_map)
		return 0;
	for (p = state->selector_map; p->id; p++) {
		if (p->id == unitid && index < p->count)
			return strlcpy(buf, p->names[index], buflen);
	}
	return 0;
}

/*
 * find an audio control unit with the given unit id
 */
static void *find_audio_control_unit(struct mixer_build *state,
				     unsigned char unit)
{
	/* we just parse the header */
	struct uac_feature_unit_descriptor *hdr = NULL;

	while ((hdr = snd_usb_find_desc(state->buffer, state->buflen, hdr,
					USB_DT_CS_INTERFACE)) != NULL) {
		if (hdr->bLength >= 4 &&
		    hdr->bDescriptorSubtype >= UAC_INPUT_TERMINAL &&
		    hdr->bDescriptorSubtype <= UAC3_SAMPLE_RATE_CONVERTER &&
		    hdr->bUnitID == unit)
			return hdr;
	}

	return NULL;
}

/*
 * copy a string with the given id
 */
static int snd_usb_copy_string_desc(struct snd_usb_audio *chip,
				    int index, char *buf, int maxlen)
{
	int len = usb_string(chip->dev, index, buf, maxlen - 1);

	if (len < 0)
		return 0;

	buf[len] = 0;
	return len;
}

/*
 * convert from the byte/word on usb descriptor to the zero-based integer
 */
static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
{
	switch (cval->val_type) {
	case USB_MIXER_BOOLEAN:
		return !!val;
	case USB_MIXER_INV_BOOLEAN:
		return !val;
	case USB_MIXER_U8:
		val &= 0xff;
		break;
	case USB_MIXER_S8:
		val &= 0xff;
		if (val >= 0x80)
			val -= 0x100;
		break;
	case USB_MIXER_U16:
		val &= 0xffff;
		break;
	case USB_MIXER_S16:
		val &= 0xffff;
		if (val >= 0x8000)
			val -= 0x10000;
		break;
	}
	return val;
}

/*
 * convert from the zero-based int to the byte/word for usb descriptor
 */
static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
{
	switch (cval->val_type) {
	case USB_MIXER_BOOLEAN:
		return !!val;
	case USB_MIXER_INV_BOOLEAN:
		return !val;
	case USB_MIXER_S8:
	case USB_MIXER_U8:
		return val & 0xff;
	case USB_MIXER_S16:
	case USB_MIXER_U16:
		return val & 0xffff;
	}
	return 0; /* not reached */
}

static int get_relative_value(struct usb_mixer_elem_info *cval, int val)
{
	if (!cval->res)
		cval->res = 1;
	if (val < cval->min)
		return 0;
	else if (val >= cval->max)
		return (cval->max - cval->min + cval->res - 1) / cval->res;
	else
		return (val - cval->min) / cval->res;
}

static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
{
	if (val < 0)
		return cval->min;
	if (!cval->res)
		cval->res = 1;
	val *= cval->res;
	val += cval->min;
	if (val > cval->max)
		return cval->max;
	return val;
}

static int uac2_ctl_value_size(int val_type)
{
	switch (val_type) {
	case USB_MIXER_S32:
	case USB_MIXER_U32:
		return 4;
	case USB_MIXER_S16:
	case USB_MIXER_U16:
		return 2;
	default:
		return 1;
	}
	return 0; /* unreachable */
}


/*
 * retrieve a mixer value
 */

static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request,
			    int validx, int *value_ret)
{
	struct snd_usb_audio *chip = cval->head.mixer->chip;
	unsigned char buf[2];
	int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
	int timeout = 10;
	int idx = 0, err;

	err = snd_usb_lock_shutdown(chip);
	if (err < 0)
		return -EIO;

	while (timeout-- > 0) {
		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
		err = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
				      validx, idx, buf, val_len);
		if (err >= val_len) {
			*value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
			err = 0;
			goto out;
		} else if (err == -ETIMEDOUT) {
			goto out;
		}
	}
	usb_audio_dbg(chip,
		"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
		request, validx, idx, cval->val_type);
	err = -EINVAL;

 out:
	snd_usb_unlock_shutdown(chip);
	return err;
}

static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
			    int validx, int *value_ret)
{
	struct snd_usb_audio *chip = cval->head.mixer->chip;
	/* enough space for one range */
	unsigned char buf[sizeof(__u16) + 3 * sizeof(__u32)];
	unsigned char *val;
	int idx = 0, ret, val_size, size;
	__u8 bRequest;

	val_size = uac2_ctl_value_size(cval->val_type);

	if (request == UAC_GET_CUR) {
		bRequest = UAC2_CS_CUR;
		size = val_size;
	} else {
		bRequest = UAC2_CS_RANGE;
		size = sizeof(__u16) + 3 * val_size;
	}

	memset(buf, 0, sizeof(buf));

	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
	if (ret)
		goto error;

	idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
			      validx, idx, buf, size);
	snd_usb_unlock_shutdown(chip);

	if (ret < 0) {
error:
		usb_audio_err(chip,
			"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
			request, validx, idx, cval->val_type);
		return ret;
	}

	/* FIXME: how should we handle multiple triplets here? */

	switch (request) {
	case UAC_GET_CUR:
		val = buf;
		break;
	case UAC_GET_MIN:
		val = buf + sizeof(__u16);
		break;
	case UAC_GET_MAX:
		val = buf + sizeof(__u16) + val_size;
		break;
	case UAC_GET_RES:
		val = buf + sizeof(__u16) + val_size * 2;
		break;
	default:
		return -EINVAL;
	}

	*value_ret = convert_signed_value(cval,
					  snd_usb_combine_bytes(val, val_size));

	return 0;
}

static int get_ctl_value(struct usb_mixer_elem_info *cval, int request,
			 int validx, int *value_ret)
{
	validx += cval->idx_off;

	return (cval->head.mixer->protocol == UAC_VERSION_1) ?
		get_ctl_value_v1(cval, request, validx, value_ret) :
		get_ctl_value_v2(cval, request, validx, value_ret);
}

static int get_cur_ctl_value(struct usb_mixer_elem_info *cval,
			     int validx, int *value)
{
	return get_ctl_value(cval, UAC_GET_CUR, validx, value);
}

/* channel = 0: master, 1 = first channel */
static inline int get_cur_mix_raw(struct usb_mixer_elem_info *cval,
				  int channel, int *value)
{
	return get_ctl_value(cval, UAC_GET_CUR,
			     (cval->control << 8) | channel,
			     value);
}

int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
			     int channel, int index, int *value)
{
	int err;

	if (cval->cached & (1 << channel)) {
		*value = cval->cache_val[index];
		return 0;
	}
	err = get_cur_mix_raw(cval, channel, value);
	if (err < 0) {
		if (!cval->head.mixer->ignore_ctl_error)
			usb_audio_dbg(cval->head.mixer->chip,
				"cannot get current value for control %d ch %d: err = %d\n",
				      cval->control, channel, err);
		return err;
	}
	cval->cached |= 1 << channel;
	cval->cache_val[index] = *value;
	return 0;
}

/*
 * set a mixer value
 */

int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
				int request, int validx, int value_set)
{
	struct snd_usb_audio *chip = cval->head.mixer->chip;
	unsigned char buf[4];
	int idx = 0, val_len, err, timeout = 10;

	validx += cval->idx_off;


	if (cval->head.mixer->protocol == UAC_VERSION_1) {
		val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
	} else { /* UAC_VERSION_2/3 */
		val_len = uac2_ctl_value_size(cval->val_type);

		/* FIXME */
		if (request != UAC_SET_CUR) {
			usb_audio_dbg(chip, "RANGE setting not yet supported\n");
			return -EINVAL;
		}

		request = UAC2_CS_CUR;
	}

	value_set = convert_bytes_value(cval, value_set);
	buf[0] = value_set & 0xff;
	buf[1] = (value_set >> 8) & 0xff;
	buf[2] = (value_set >> 16) & 0xff;
	buf[3] = (value_set >> 24) & 0xff;

	err = snd_usb_lock_shutdown(chip);
	if (err < 0)
		return -EIO;

	while (timeout-- > 0) {
		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
		err = snd_usb_ctl_msg(chip->dev,
				      usb_sndctrlpipe(chip->dev, 0), request,
				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
				      validx, idx, buf, val_len);
		if (err >= 0) {
			err = 0;
			goto out;
		} else if (err == -ETIMEDOUT) {
			goto out;
		}
	}
	usb_audio_dbg(chip, "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
		      request, validx, idx, cval->val_type, buf[0], buf[1]);
	err = -EINVAL;

 out:
	snd_usb_unlock_shutdown(chip);
	return err;
}

static int set_cur_ctl_value(struct usb_mixer_elem_info *cval,
			     int validx, int value)
{
	return snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, validx, value);
}

int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
			     int index, int value)
{
	int err;
	unsigned int read_only = (channel == 0) ?
		cval->master_readonly :
		cval->ch_readonly & (1 << (channel - 1));

	if (read_only) {
		usb_audio_dbg(cval->head.mixer->chip,
			      "%s(): channel %d of control %d is read_only\n",
			    __func__, channel, cval->control);
		return 0;
	}

	err = snd_usb_mixer_set_ctl_value(cval,
					  UAC_SET_CUR, (cval->control << 8) | channel,
					  value);
	if (err < 0)
		return err;
	cval->cached |= 1 << channel;
	cval->cache_val[index] = value;
	return 0;
}

/*
 * TLV callback for mixer volume controls
 */
int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
			 unsigned int size, unsigned int __user *_tlv)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	DECLARE_TLV_DB_MINMAX(scale, 0, 0);

	if (size < sizeof(scale))
		return -ENOMEM;
	if (cval->min_mute)
		scale[0] = SNDRV_CTL_TLVT_DB_MINMAX_MUTE;
	scale[2] = cval->dBmin;
	scale[3] = cval->dBmax;
	if (copy_to_user(_tlv, scale, sizeof(scale)))
		return -EFAULT;
	return 0;
}

/*
 * parser routines begin here...
 */

static int parse_audio_unit(struct mixer_build *state, int unitid);


/*
 * check if the input/output channel routing is enabled on the given bitmap.
 * used for mixer unit parser
 */
static int check_matrix_bitmap(unsigned char *bmap,
			       int ich, int och, int num_outs)
{
	int idx = ich * num_outs + och;
	return bmap[idx >> 3] & (0x80 >> (idx & 7));
}

/*
 * add an alsa control element
 * search and increment the index until an empty slot is found.
 *
 * if failed, give up and free the control instance.
 */

int snd_usb_mixer_add_control(struct usb_mixer_elem_list *list,
			      struct snd_kcontrol *kctl)
{
	struct usb_mixer_interface *mixer = list->mixer;
	int err;

	while (snd_ctl_find_id(mixer->chip->card, &kctl->id))
		kctl->id.index++;
	err = snd_ctl_add(mixer->chip->card, kctl);
	if (err < 0) {
		usb_audio_dbg(mixer->chip, "cannot add control (err = %d)\n",
			      err);
		return err;
	}
	list->kctl = kctl;
	list->next_id_elem = mixer->id_elems[list->id];
	mixer->id_elems[list->id] = list;
	return 0;
}

/*
 * get a terminal name string
 */

static struct iterm_name_combo {
	int type;
	char *name;
} iterm_names[] = {
	{ 0x0300, "Output" },
	{ 0x0301, "Speaker" },
	{ 0x0302, "Headphone" },
	{ 0x0303, "HMD Audio" },
	{ 0x0304, "Desktop Speaker" },
	{ 0x0305, "Room Speaker" },
	{ 0x0306, "Com Speaker" },
	{ 0x0307, "LFE" },
	{ 0x0600, "External In" },
	{ 0x0601, "Analog In" },
	{ 0x0602, "Digital In" },
	{ 0x0603, "Line" },
	{ 0x0604, "Legacy In" },
	{ 0x0605, "IEC958 In" },
	{ 0x0606, "1394 DA Stream" },
	{ 0x0607, "1394 DV Stream" },
	{ 0x0700, "Embedded" },
	{ 0x0701, "Noise Source" },
	{ 0x0702, "Equalization Noise" },
	{ 0x0703, "CD" },
	{ 0x0704, "DAT" },
	{ 0x0705, "DCC" },
	{ 0x0706, "MiniDisk" },
	{ 0x0707, "Analog Tape" },
	{ 0x0708, "Phonograph" },
	{ 0x0709, "VCR Audio" },
	{ 0x070a, "Video Disk Audio" },
	{ 0x070b, "DVD Audio" },
	{ 0x070c, "TV Tuner Audio" },
	{ 0x070d, "Satellite Rec Audio" },
	{ 0x070e, "Cable Tuner Audio" },
	{ 0x070f, "DSS Audio" },
	{ 0x0710, "Radio Receiver" },
	{ 0x0711, "Radio Transmitter" },
	{ 0x0712, "Multi-Track Recorder" },
	{ 0x0713, "Synthesizer" },
	{ 0 },
};

static int get_term_name(struct snd_usb_audio *chip, struct usb_audio_term *iterm,
			 unsigned char *name, int maxlen, int term_only)
{
	struct iterm_name_combo *names;
	int len;

	if (iterm->name) {
		len = snd_usb_copy_string_desc(chip, iterm->name,
						name, maxlen);
		if (len)
			return len;
	}

	/* virtual type - not a real terminal */
	if (iterm->type >> 16) {
		if (term_only)
			return 0;
		switch (iterm->type >> 16) {
		case UAC3_SELECTOR_UNIT:
			strcpy(name, "Selector");
			return 8;
		case UAC3_PROCESSING_UNIT:
			strcpy(name, "Process Unit");
			return 12;
		case UAC3_EXTENSION_UNIT:
			strcpy(name, "Ext Unit");
			return 8;
		case UAC3_MIXER_UNIT:
			strcpy(name, "Mixer");
			return 5;
		default:
			return sprintf(name, "Unit %d", iterm->id);
		}
	}

	switch (iterm->type & 0xff00) {
	case 0x0100:
		strcpy(name, "PCM");
		return 3;
	case 0x0200:
		strcpy(name, "Mic");
		return 3;
	case 0x0400:
		strcpy(name, "Headset");
		return 7;
	case 0x0500:
		strcpy(name, "Phone");
		return 5;
	}

	for (names = iterm_names; names->type; names++) {
		if (names->type == iterm->type) {
			strcpy(name, names->name);
			return strlen(names->name);
		}
	}

	return 0;
}

/*
 * Get logical cluster information for UAC3 devices.
 */
static int get_cluster_channels_v3(struct mixer_build *state, unsigned int cluster_id)
{
	struct uac3_cluster_header_descriptor c_header;
	int err;

	err = snd_usb_ctl_msg(state->chip->dev,
			usb_rcvctrlpipe(state->chip->dev, 0),
			UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
			USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
			cluster_id,
			snd_usb_ctrl_intf(state->chip),
			&c_header, sizeof(c_header));
	if (err < 0)
		goto error;
	if (err != sizeof(c_header)) {
		err = -EIO;
		goto error;
	}

	return c_header.bNrChannels;

error:
	usb_audio_err(state->chip, "cannot request logical cluster ID: %d (err: %d)\n", cluster_id, err);
	return err;
}

/*
 * Get number of channels for a Mixer Unit.
 */
static int uac_mixer_unit_get_channels(struct mixer_build *state,
				       struct uac_mixer_unit_descriptor *desc)
{
	int mu_channels;

	switch (state->mixer->protocol) {
	case UAC_VERSION_1:
	case UAC_VERSION_2:
	default:
		if (desc->bLength < sizeof(*desc) + desc->bNrInPins + 1)
			return 0; /* no bmControls -> skip */
		mu_channels = uac_mixer_unit_bNrChannels(desc);
		break;
	case UAC_VERSION_3:
		mu_channels = get_cluster_channels_v3(state,
				uac3_mixer_unit_wClusterDescrID(desc));
		break;
	}

	return mu_channels;
}

/*
 * Parse Input Terminal Unit
 */
static int __check_input_term(struct mixer_build *state, int id,
			      struct usb_audio_term *term);

static int parse_term_uac1_iterm_unit(struct mixer_build *state,
				      struct usb_audio_term *term,
				      void *p1, int id)
{
	struct uac_input_terminal_descriptor *d = p1;

	term->type = le16_to_cpu(d->wTerminalType);
	term->channels = d->bNrChannels;
	term->chconfig = le16_to_cpu(d->wChannelConfig);
	term->name = d->iTerminal;
	return 0;
}

static int parse_term_uac2_iterm_unit(struct mixer_build *state,
				      struct usb_audio_term *term,
				      void *p1, int id)
{
	struct uac2_input_terminal_descriptor *d = p1;
	int err;

	/* call recursively to verify the referenced clock entity */
	err = __check_input_term(state, d->bCSourceID, term);
	if (err < 0)
		return err;

	/* save input term properties after recursion,
	 * to ensure they are not overriden by the recursion calls
	 */
	term->id = id;
	term->type = le16_to_cpu(d->wTerminalType);
	term->channels = d->bNrChannels;
	term->chconfig = le32_to_cpu(d->bmChannelConfig);
	term->name = d->iTerminal;
	return 0;
}

static int parse_term_uac3_iterm_unit(struct mixer_build *state,
				      struct usb_audio_term *term,
				      void *p1, int id)
{
	struct uac3_input_terminal_descriptor *d = p1;
	int err;

	/* call recursively to verify the referenced clock entity */
	err = __check_input_term(state, d->bCSourceID, term);
	if (err < 0)
		return err;

	/* save input term properties after recursion,
	 * to ensure they are not overriden by the recursion calls
	 */
	term->id = id;
	term->type = le16_to_cpu(d->wTerminalType);

	err = get_cluster_channels_v3(state, le16_to_cpu(d->wClusterDescrID));
	if (err < 0)
		return err;
	term->channels = err;

	/* REVISIT: UAC3 IT doesn't have channels cfg */
	term->chconfig = 0;

	term->name = le16_to_cpu(d->wTerminalDescrStr);
	return 0;
}

static int parse_term_mixer_unit(struct mixer_build *state,
				 struct usb_audio_term *term,
				 void *p1, int id)
{
	struct uac_mixer_unit_descriptor *d = p1;
	int protocol = state->mixer->protocol;
	int err;

	err = uac_mixer_unit_get_channels(state, d);
	if (err <= 0)
		return err;

	term->type = UAC3_MIXER_UNIT << 16; /* virtual type */
	term->channels = err;
	if (protocol != UAC_VERSION_3) {
		term->chconfig = uac_mixer_unit_wChannelConfig(d, protocol);
		term->name = uac_mixer_unit_iMixer(d);
	}
	return 0;
}

static int parse_term_selector_unit(struct mixer_build *state,
				    struct usb_audio_term *term,
				    void *p1, int id)
{
	struct uac_selector_unit_descriptor *d = p1;
	int err;

	/* call recursively to retrieve the channel info */
	err = __check_input_term(state, d->baSourceID[0], term);
	if (err < 0)
		return err;
	term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */
	term->id = id;
	if (state->mixer->protocol != UAC_VERSION_3)
		term->name = uac_selector_unit_iSelector(d);
	return 0;
}

static int parse_term_proc_unit(struct mixer_build *state,
				struct usb_audio_term *term,
				void *p1, int id, int vtype)
{
	struct uac_processing_unit_descriptor *d = p1;
	int protocol = state->mixer->protocol;
	int err;

	if (d->bNrInPins) {
		/* call recursively to retrieve the channel info */
		err = __check_input_term(state, d->baSourceID[0], term);
		if (err < 0)
			return err;
	}

	term->type = vtype << 16; /* virtual type */
	term->id = id;

	if (protocol == UAC_VERSION_3)
		return 0;

	if (!term->channels) {
		term->channels = uac_processing_unit_bNrChannels(d);
		term->chconfig = uac_processing_unit_wChannelConfig(d, protocol);
	}
	term->name = uac_processing_unit_iProcessing(d, protocol);
	return 0;
}

static int parse_term_uac2_clock_source(struct mixer_build *state,
					struct usb_audio_term *term,
					void *p1, int id)
{
	struct uac_clock_source_descriptor *d = p1;

	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
	term->id = id;
	term->name = d->iClockSource;
	return 0;
}

static int parse_term_uac3_clock_source(struct mixer_build *state,
					struct usb_audio_term *term,
					void *p1, int id)
{
	struct uac3_clock_source_descriptor *d = p1;

	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
	term->id = id;
	term->name = le16_to_cpu(d->wClockSourceStr);
	return 0;
}

#define PTYPE(a, b)	((a) << 8 | (b))

/*
 * parse the source unit recursively until it reaches to a terminal
 * or a branched unit.
 */
static int __check_input_term(struct mixer_build *state, int id,
			      struct usb_audio_term *term)
{
	int protocol = state->mixer->protocol;
	void *p1;
	unsigned char *hdr;

	for (;;) {
		/* a loop in the terminal chain? */
		if (test_and_set_bit(id, state->termbitmap))
			return -EINVAL;

		p1 = find_audio_control_unit(state, id);
		if (!p1)
			break;
		if (!snd_usb_validate_audio_desc(p1, protocol))
			break; /* bad descriptor */

		hdr = p1;
		term->id = id;

		switch (PTYPE(protocol, hdr[2])) {
		case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):
		case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):
		case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT): {
			/* the header is the same for all versions */
			struct uac_feature_unit_descriptor *d = p1;

			id = d->bSourceID;
			break; /* continue to parse */
		}
		case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):
			return parse_term_uac1_iterm_unit(state, term, p1, id);
		case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):
			return parse_term_uac2_iterm_unit(state, term, p1, id);
		case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):
			return parse_term_uac3_iterm_unit(state, term, p1, id);
		case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):
		case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):
		case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):
			return parse_term_mixer_unit(state, term, p1, id);
		case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):
		case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):
		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):
		case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):
		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):
			return parse_term_selector_unit(state, term, p1, id);
		case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):
		case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):
		case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):
			return parse_term_proc_unit(state, term, p1, id,
						    UAC3_PROCESSING_UNIT);
		case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):
		case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):
			return parse_term_proc_unit(state, term, p1, id,
						    UAC3_EFFECT_UNIT);
		case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):
		case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):
		case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):
			return parse_term_proc_unit(state, term, p1, id,
						    UAC3_EXTENSION_UNIT);
		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):
			return parse_term_uac2_clock_source(state, term, p1, id);
		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):
			return parse_term_uac3_clock_source(state, term, p1, id);
		default:
			return -ENODEV;
		}
	}
	return -ENODEV;
}


static int check_input_term(struct mixer_build *state, int id,
			    struct usb_audio_term *term)
{
	memset(term, 0, sizeof(*term));
	memset(state->termbitmap, 0, sizeof(state->termbitmap));
	return __check_input_term(state, id, term);
}

/*
 * Feature Unit
 */

/* feature unit control information */
struct usb_feature_control_info {
	int control;
	const char *name;
	int type;	/* data type for uac1 */
	int type_uac2;	/* data type for uac2 if different from uac1, else -1 */
};

static struct usb_feature_control_info audio_feature_info[] = {
	{ UAC_FU_MUTE,			"Mute",			USB_MIXER_INV_BOOLEAN, -1 },
	{ UAC_FU_VOLUME,		"Volume",		USB_MIXER_S16, -1 },
	{ UAC_FU_BASS,			"Tone Control - Bass",	USB_MIXER_S8, -1 },
	{ UAC_FU_MID,			"Tone Control - Mid",	USB_MIXER_S8, -1 },
	{ UAC_FU_TREBLE,		"Tone Control - Treble", USB_MIXER_S8, -1 },
	{ UAC_FU_GRAPHIC_EQUALIZER,	"Graphic Equalizer",	USB_MIXER_S8, -1 }, /* FIXME: not implemented yet */
	{ UAC_FU_AUTOMATIC_GAIN,	"Auto Gain Control",	USB_MIXER_BOOLEAN, -1 },
	{ UAC_FU_DELAY,			"Delay Control",	USB_MIXER_U16, USB_MIXER_U32 },
	{ UAC_FU_BASS_BOOST,		"Bass Boost",		USB_MIXER_BOOLEAN, -1 },
	{ UAC_FU_LOUDNESS,		"Loudness",		USB_MIXER_BOOLEAN, -1 },
	/* UAC2 specific */
	{ UAC2_FU_INPUT_GAIN,		"Input Gain Control",	USB_MIXER_S16, -1 },
	{ UAC2_FU_INPUT_GAIN_PAD,	"Input Gain Pad Control", USB_MIXER_S16, -1 },
	{ UAC2_FU_PHASE_INVERTER,	 "Phase Inverter Control", USB_MIXER_BOOLEAN, -1 },
};

static void usb_mixer_elem_info_free(struct usb_mixer_elem_info *cval)
{
	kfree(cval);
}

/* private_free callback */
void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
{
	usb_mixer_elem_info_free(kctl->private_data);
	kctl->private_data = NULL;
}

/*
 * interface to ALSA control for feature/mixer units
 */

/* volume control quirks */
static void volume_control_quirks(struct usb_mixer_elem_info *cval,
				  struct snd_kcontrol *kctl)
{
	struct snd_usb_audio *chip = cval->head.mixer->chip;
	switch (chip->usb_id) {
	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
			cval->min = 0x0000;
			cval->max = 0xffff;
			cval->res = 0x00e6;
			break;
		}
		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
			cval->min = 0x00;
			cval->max = 0xff;
			break;
		}
		if (strstr(kctl->id.name, "Effect Return") != NULL) {
			cval->min = 0xb706;
			cval->max = 0xff7b;
			cval->res = 0x0073;
			break;
		}
		if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
			(strstr(kctl->id.name, "Effect Send") != NULL)) {
			cval->min = 0xb5fb; /* -73 dB = 0xb6ff */
			cval->max = 0xfcfe;
			cval->res = 0x0073;
		}
		break;

	case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */
	case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
			usb_audio_info(chip,
				       "set quirk for FTU Effect Duration\n");
			cval->min = 0x0000;
			cval->max = 0x7f00;
			cval->res = 0x0100;
			break;
		}
		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
			usb_audio_info(chip,
				       "set quirks for FTU Effect Feedback/Volume\n");
			cval->min = 0x00;
			cval->max = 0x7f;
			break;
		}
		break;

	case USB_ID(0x0d8c, 0x0103):
		if (!strcmp(kctl->id.name, "PCM Playback Volume")) {
			usb_audio_info(chip,
				 "set volume quirk for CM102-A+/102S+\n");
			cval->min = -256;
		}
		break;

	case USB_ID(0x0471, 0x0101):
	case USB_ID(0x0471, 0x0104):
	case USB_ID(0x0471, 0x0105):
	case USB_ID(0x0672, 0x1041):
	/* quirk for UDA1321/N101.
	 * note that detection between firmware 2.1.1.7 (N101)
	 * and later 2.1.1.21 is not very clear from datasheets.
	 * I hope that the min value is -15360 for newer firmware --jk
	 */
		if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
		    cval->min == -15616) {
			usb_audio_info(chip,
				 "set volume quirk for UDA1321/N101 chip\n");
			cval->max = -256;
		}
		break;

	case USB_ID(0x046d, 0x09a4):
		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
			usb_audio_info(chip,
				"set volume quirk for QuickCam E3500\n");
			cval->min = 6080;
			cval->max = 8768;
			cval->res = 192;
		}
		break;

	case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
	case USB_ID(0x046d, 0x0808):
	case USB_ID(0x046d, 0x0809):
	case USB_ID(0x046d, 0x0819): /* Logitech Webcam C210 */
	case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
	case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
	case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
	case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
	case USB_ID(0x046d, 0x08ca): /* Logitech Quickcam Fusion */
	case USB_ID(0x046d, 0x0991):
	case USB_ID(0x046d, 0x09a2): /* QuickCam Communicate Deluxe/S7500 */
	/* Most audio usb devices lie about volume resolution.
	 * Most Logitech webcams have res = 384.
	 * Probably there is some logitech magic behind this number --fishor
	 */
		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
			usb_audio_info(chip,
				"set resolution quirk: cval->res = 384\n");
			cval->res = 384;
		}
		break;
	}
}

/*
 * retrieve the minimum and maximum values for the specified control
 */
static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
				   int default_min, struct snd_kcontrol *kctl)
{
	/* for failsafe */
	cval->min = default_min;
	cval->max = cval->min + 1;
	cval->res = 1;
	cval->dBmin = cval->dBmax = 0;

	if (cval->val_type == USB_MIXER_BOOLEAN ||
	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
		cval->initialized = 1;
	} else {
		int minchn = 0;
		if (cval->cmask) {
			int i;
			for (i = 0; i < MAX_CHANNELS; i++)
				if (cval->cmask & (1 << i)) {
					minchn = i + 1;
					break;
				}
		}
		if (get_ctl_value(cval, UAC_GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
		    get_ctl_value(cval, UAC_GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
			usb_audio_err(cval->head.mixer->chip,
				      "%d:%d: cannot get min/max values for control %d (id %d)\n",
				   cval->head.id, snd_usb_ctrl_intf(cval->head.mixer->chip),
							       cval->control, cval->head.id);
			return -EINVAL;
		}
		if (get_ctl_value(cval, UAC_GET_RES,
				  (cval->control << 8) | minchn,
				  &cval->res) < 0) {
			cval->res = 1;
		} else {
			int last_valid_res = cval->res;

			while (cval->res > 1) {
				if (snd_usb_mixer_set_ctl_value(cval, UAC_SET_RES,
								(cval->control << 8) | minchn,
								cval->res / 2) < 0)
					break;
				cval->res /= 2;
			}
			if (get_ctl_value(cval, UAC_GET_RES,
					  (cval->control << 8) | minchn, &cval->res) < 0)
				cval->res = last_valid_res;
		}
		if (cval->res == 0)
			cval->res = 1;

		/* Additional checks for the proper resolution
		 *
		 * Some devices report smaller resolutions than actually
		 * reacting.  They don't return errors but simply clip
		 * to the lower aligned value.
		 */
		if (cval->min + cval->res < cval->max) {
			int last_valid_res = cval->res;
			int saved, test, check;
			if (get_cur_mix_raw(cval, minchn, &saved) < 0)
				goto no_res_check;
			for (;;) {
				test = saved;
				if (test < cval->max)
					test += cval->res;
				else
					test -= cval->res;
				if (test < cval->min || test > cval->max ||
				    snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||
				    get_cur_mix_raw(cval, minchn, &check)) {
					cval->res = last_valid_res;
					break;
				}
				if (test == check)
					break;
				cval->res *= 2;
			}
			snd_usb_set_cur_mix_value(cval, minchn, 0, saved);
		}

no_res_check:
		cval->initialized = 1;
	}

	if (kctl)
		volume_control_quirks(cval, kctl);

	/* USB descriptions contain the dB scale in 1/256 dB unit
	 * while ALSA TLV contains in 1/100 dB unit
	 */
	cval->dBmin = (convert_signed_value(cval, cval->min) * 100) / 256;
	cval->dBmax = (convert_signed_value(cval, cval->max) * 100) / 256;
	if (cval->dBmin > cval->dBmax) {
		/* something is wrong; assume it's either from/to 0dB */
		if (cval->dBmin < 0)
			cval->dBmax = 0;
		else if (cval->dBmin > 0)
			cval->dBmin = 0;
		if (cval->dBmin > cval->dBmax) {
			/* totally crap, return an error */
			return -EINVAL;
		}
	}

	return 0;
}

#define get_min_max(cval, def)	get_min_max_with_quirks(cval, def, NULL)

/* get a feature/mixer unit info */
static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol,
				  struct snd_ctl_elem_info *uinfo)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;

	if (cval->val_type == USB_MIXER_BOOLEAN ||
	    cval->val_type == USB_MIXER_INV_BOOLEAN)
		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
	else
		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	uinfo->count = cval->channels;
	if (cval->val_type == USB_MIXER_BOOLEAN ||
	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
		uinfo->value.integer.min = 0;
		uinfo->value.integer.max = 1;
	} else {
		if (!cval->initialized) {
			get_min_max_with_quirks(cval, 0, kcontrol);
			if (cval->initialized && cval->dBmin >= cval->dBmax) {
				kcontrol->vd[0].access &= 
					~(SNDRV_CTL_ELEM_ACCESS_TLV_READ |
					  SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
				snd_ctl_notify(cval->head.mixer->chip->card,
					       SNDRV_CTL_EVENT_MASK_INFO,
					       &kcontrol->id);
			}
		}
		uinfo->value.integer.min = 0;
		uinfo->value.integer.max =
			(cval->max - cval->min + cval->res - 1) / cval->res;
	}
	return 0;
}

/* get the current value from feature/mixer unit */
static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol,
				 struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int c, cnt, val, err;

	ucontrol->value.integer.value[0] = cval->min;
	if (cval->cmask) {
		cnt = 0;
		for (c = 0; c < MAX_CHANNELS; c++) {
			if (!(cval->cmask & (1 << c)))
				continue;
			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &val);
			if (err < 0)
				return filter_error(cval, err);
			val = get_relative_value(cval, val);
			ucontrol->value.integer.value[cnt] = val;
			cnt++;
		}
		return 0;
	} else {
		/* master channel */
		err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
		if (err < 0)
			return filter_error(cval, err);
		val = get_relative_value(cval, val);
		ucontrol->value.integer.value[0] = val;
	}
	return 0;
}

/* put the current value to feature/mixer unit */
static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol,
				 struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int c, cnt, val, oval, err;
	int changed = 0;

	if (cval->cmask) {
		cnt = 0;
		for (c = 0; c < MAX_CHANNELS; c++) {
			if (!(cval->cmask & (1 << c)))
				continue;
			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &oval);
			if (err < 0)
				return filter_error(cval, err);
			val = ucontrol->value.integer.value[cnt];
			val = get_abs_value(cval, val);
			if (oval != val) {
				snd_usb_set_cur_mix_value(cval, c + 1, cnt, val);
				changed = 1;
			}
			cnt++;
		}
	} else {
		/* master channel */
		err = snd_usb_get_cur_mix_value(cval, 0, 0, &oval);
		if (err < 0)
			return filter_error(cval, err);
		val = ucontrol->value.integer.value[0];
		val = get_abs_value(cval, val);
		if (val != oval) {
			snd_usb_set_cur_mix_value(cval, 0, 0, val);
			changed = 1;
		}
	}
	return changed;
}

/* get the boolean value from the master channel of a UAC control */
static int mixer_ctl_master_bool_get(struct snd_kcontrol *kcontrol,
				     struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int val, err;

	err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
	if (err < 0)
		return filter_error(cval, err);
	val = (val != 0);
	ucontrol->value.integer.value[0] = val;
	return 0;
}

/* get the connectors status and report it as boolean type */
static int mixer_ctl_connector_get(struct snd_kcontrol *kcontrol,
				   struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	struct snd_usb_audio *chip = cval->head.mixer->chip;
	int idx = 0, validx, ret, val;

	validx = cval->control << 8 | 0;

	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
	if (ret)
		goto error;

	idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
	if (cval->head.mixer->protocol == UAC_VERSION_2) {
		struct uac2_connectors_ctl_blk uac2_conn;

		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
				      validx, idx, &uac2_conn, sizeof(uac2_conn));
		val = !!uac2_conn.bNrChannels;
	} else { /* UAC_VERSION_3 */
		struct uac3_insertion_ctl_blk uac3_conn;

		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
				      validx, idx, &uac3_conn, sizeof(uac3_conn));
		val = !!uac3_conn.bmConInserted;
	}

	snd_usb_unlock_shutdown(chip);

	if (ret < 0) {
error:
		usb_audio_err(chip,
			"cannot get connectors status: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
			UAC_GET_CUR, validx, idx, cval->val_type);
		return ret;
	}

	ucontrol->value.integer.value[0] = val;
	return 0;
}

static struct snd_kcontrol_new usb_feature_unit_ctl = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "", /* will be filled later manually */
	.info = mixer_ctl_feature_info,
	.get = mixer_ctl_feature_get,
	.put = mixer_ctl_feature_put,
};

/* the read-only variant */
static const struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "", /* will be filled later manually */
	.info = mixer_ctl_feature_info,
	.get = mixer_ctl_feature_get,
	.put = NULL,
};

/*
 * A control which shows the boolean value from reading a UAC control on
 * the master channel.
 */
static struct snd_kcontrol_new usb_bool_master_control_ctl_ro = {
	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
	.name = "", /* will be filled later manually */
	.access = SNDRV_CTL_ELEM_ACCESS_READ,
	.info = snd_ctl_boolean_mono_info,
	.get = mixer_ctl_master_bool_get,
	.put = NULL,
};

static const struct snd_kcontrol_new usb_connector_ctl_ro = {
	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
	.name = "", /* will be filled later manually */
	.access = SNDRV_CTL_ELEM_ACCESS_READ,
	.info = snd_ctl_boolean_mono_info,
	.get = mixer_ctl_connector_get,
	.put = NULL,
};

/*
 * This symbol is exported in order to allow the mixer quirks to
 * hook up to the standard feature unit control mechanism
 */
struct snd_kcontrol_new *snd_usb_feature_unit_ctl = &usb_feature_unit_ctl;

/*
 * build a feature control
 */
static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
{
	return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
}

/*
 * A lot of headsets/headphones have a "Speaker" mixer. Make sure we
 * rename it to "Headphone". We determine if something is a headphone
 * similar to how udev determines form factor.
 */
static void check_no_speaker_on_headset(struct snd_kcontrol *kctl,
					struct snd_card *card)
{
	const char *names_to_check[] = {
		"Headset", "headset", "Headphone", "headphone", NULL};
	const char **s;
	bool found = false;

	if (strcmp("Speaker", kctl->id.name))
		return;

	for (s = names_to_check; *s; s++)
		if (strstr(card->shortname, *s)) {
			found = true;
			break;
		}

	if (!found)
		return;

	strlcpy(kctl->id.name, "Headphone", sizeof(kctl->id.name));
}

static struct usb_feature_control_info *get_feature_control_info(int control)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(audio_feature_info); ++i) {
		if (audio_feature_info[i].control == control)
			return &audio_feature_info[i];
	}
	return NULL;
}

static void __build_feature_ctl(struct usb_mixer_interface *mixer,
				const struct usbmix_name_map *imap,
				unsigned int ctl_mask, int control,
				struct usb_audio_term *iterm,
				struct usb_audio_term *oterm,
				int unitid, int nameid, int readonly_mask)
{
	struct usb_feature_control_info *ctl_info;
	unsigned int len = 0;
	int mapped_name = 0;
	struct snd_kcontrol *kctl;
	struct usb_mixer_elem_info *cval;
	const struct usbmix_name_map *map;
	unsigned int range;

	if (control == UAC_FU_GRAPHIC_EQUALIZER) {
		/* FIXME: not supported yet */
		return;
	}

	map = find_map(imap, unitid, control);
	if (check_ignored_ctl(map))
		return;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (!cval)
		return;
	snd_usb_mixer_elem_init_std(&cval->head, mixer, unitid);
	cval->control = control;
	cval->cmask = ctl_mask;

	ctl_info = get_feature_control_info(control);
	if (!ctl_info) {
		usb_mixer_elem_info_free(cval);
		return;
	}
	if (mixer->protocol == UAC_VERSION_1)
		cval->val_type = ctl_info->type;
	else /* UAC_VERSION_2 */
		cval->val_type = ctl_info->type_uac2 >= 0 ?
			ctl_info->type_uac2 : ctl_info->type;

	if (ctl_mask == 0) {
		cval->channels = 1;	/* master channel */
		cval->master_readonly = readonly_mask;
	} else {
		int i, c = 0;
		for (i = 0; i < 16; i++)
			if (ctl_mask & (1 << i))
				c++;
		cval->channels = c;
		cval->ch_readonly = readonly_mask;
	}

	/*
	 * If all channels in the mask are marked read-only, make the control
	 * read-only. snd_usb_set_cur_mix_value() will check the mask again and won't
	 * issue write commands to read-only channels.
	 */
	if (cval->channels == readonly_mask)
		kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
	else
		kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);

	if (!kctl) {
		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
		usb_mixer_elem_info_free(cval);
		return;
	}
	kctl->private_free = snd_usb_mixer_elem_free;

	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
	mapped_name = len != 0;
	if (!len && nameid)
		len = snd_usb_copy_string_desc(mixer->chip, nameid,
				kctl->id.name, sizeof(kctl->id.name));

	switch (control) {
	case UAC_FU_MUTE:
	case UAC_FU_VOLUME:
		/*
		 * determine the control name.  the rule is:
		 * - if a name id is given in descriptor, use it.
		 * - if the connected input can be determined, then use the name
		 *   of terminal type.
		 * - if the connected output can be determined, use it.
		 * - otherwise, anonymous name.
		 */
		if (!len) {
			if (iterm)
				len = get_term_name(mixer->chip, iterm,
						    kctl->id.name,
						    sizeof(kctl->id.name), 1);
			if (!len && oterm)
				len = get_term_name(mixer->chip, oterm,
						    kctl->id.name,
						    sizeof(kctl->id.name), 1);
			if (!len)
				snprintf(kctl->id.name, sizeof(kctl->id.name),
					 "Feature %d", unitid);
		}

		if (!mapped_name)
			check_no_speaker_on_headset(kctl, mixer->chip->card);

		/*
		 * determine the stream direction:
		 * if the connected output is USB stream, then it's likely a
		 * capture stream.  otherwise it should be playback (hopefully :)
		 */
		if (!mapped_name && oterm && !(oterm->type >> 16)) {
			if ((oterm->type & 0xff00) == 0x0100)
				append_ctl_name(kctl, " Capture");
			else
				append_ctl_name(kctl, " Playback");
		}
		append_ctl_name(kctl, control == UAC_FU_MUTE ?
				" Switch" : " Volume");
		break;
	default:
		if (!len)
			strlcpy(kctl->id.name, audio_feature_info[control-1].name,
				sizeof(kctl->id.name));
		break;
	}

	/* get min/max values */
	get_min_max_with_quirks(cval, 0, kctl);

	if (control == UAC_FU_VOLUME) {
		check_mapped_dB(map, cval);
		if (cval->dBmin < cval->dBmax || !cval->initialized) {
			kctl->tlv.c = snd_usb_mixer_vol_tlv;
			kctl->vd[0].access |=
				SNDRV_CTL_ELEM_ACCESS_TLV_READ |
				SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
		}
	}

	snd_usb_mixer_fu_apply_quirk(mixer, cval, unitid, kctl);

	range = (cval->max - cval->min) / cval->res;
	/*
	 * Are there devices with volume range more than 255? I use a bit more
	 * to be sure. 384 is a resolution magic number found on Logitech
	 * devices. It will definitively catch all buggy Logitech devices.
	 */
	if (range > 384) {
		usb_audio_warn(mixer->chip,
			       "Warning! Unlikely big volume range (=%u), cval->res is probably wrong.",
			       range);
		usb_audio_warn(mixer->chip,
			       "[%d] FU [%s] ch = %d, val = %d/%d/%d",
			       cval->head.id, kctl->id.name, cval->channels,
			       cval->min, cval->max, cval->res);
	}

	usb_audio_dbg(mixer->chip, "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
		      cval->head.id, kctl->id.name, cval->channels,
		      cval->min, cval->max, cval->res);
	snd_usb_mixer_add_control(&cval->head, kctl);
}

static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
			      unsigned int ctl_mask, int control,
			      struct usb_audio_term *iterm, int unitid,
			      int readonly_mask)
{
	struct uac_feature_unit_descriptor *desc = raw_desc;
	int nameid = uac_feature_unit_iFeature(desc);

	__build_feature_ctl(state->mixer, state->map, ctl_mask, control,
			iterm, &state->oterm, unitid, nameid, readonly_mask);
}

static void build_feature_ctl_badd(struct usb_mixer_interface *mixer,
			      unsigned int ctl_mask, int control, int unitid,
			      const struct usbmix_name_map *badd_map)
{
	__build_feature_ctl(mixer, badd_map, ctl_mask, control,
			NULL, NULL, unitid, 0, 0);
}

static void get_connector_control_name(struct usb_mixer_interface *mixer,
				       struct usb_audio_term *term,
				       bool is_input, char *name, int name_size)
{
	int name_len = get_term_name(mixer->chip, term, name, name_size, 0);

	if (name_len == 0)
		strlcpy(name, "Unknown", name_size);

	/*
	 *  sound/core/ctljack.c has a convention of naming jack controls
	 * by ending in " Jack".  Make it slightly more useful by
	 * indicating Input or Output after the terminal name.
	 */
	if (is_input)
		strlcat(name, " - Input Jack", name_size);
	else
		strlcat(name, " - Output Jack", name_size);
}

/* Build a mixer control for a UAC connector control (jack-detect) */
static void build_connector_control(struct usb_mixer_interface *mixer,
				    struct usb_audio_term *term, bool is_input)
{
	struct snd_kcontrol *kctl;
	struct usb_mixer_elem_info *cval;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (!cval)
		return;
	snd_usb_mixer_elem_init_std(&cval->head, mixer, term->id);
	/*
	 * UAC2: The first byte from reading the UAC2_TE_CONNECTOR control returns the
	 * number of channels connected.
	 *
	 * UAC3: The first byte specifies size of bitmap for the inserted controls. The
	 * following byte(s) specifies which connectors are inserted.
	 *
	 * This boolean ctl will simply report if any channels are connected
	 * or not.
	 */
	if (mixer->protocol == UAC_VERSION_2)
		cval->control = UAC2_TE_CONNECTOR;
	else /* UAC_VERSION_3 */
		cval->control = UAC3_TE_INSERTION;

	cval->val_type = USB_MIXER_BOOLEAN;
	cval->channels = 1; /* report true if any channel is connected */
	cval->min = 0;
	cval->max = 1;
	kctl = snd_ctl_new1(&usb_connector_ctl_ro, cval);
	if (!kctl) {
		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
		usb_mixer_elem_info_free(cval);
		return;
	}
	get_connector_control_name(mixer, term, is_input, kctl->id.name,
				   sizeof(kctl->id.name));
	kctl->private_free = snd_usb_mixer_elem_free;
	snd_usb_mixer_add_control(&cval->head, kctl);
}

static int parse_clock_source_unit(struct mixer_build *state, int unitid,
				   void *_ftr)
{
	struct uac_clock_source_descriptor *hdr = _ftr;
	struct usb_mixer_elem_info *cval;
	struct snd_kcontrol *kctl;
	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
	int ret;

	if (state->mixer->protocol != UAC_VERSION_2)
		return -EINVAL;

	/*
	 * The only property of this unit we are interested in is the
	 * clock source validity. If that isn't readable, just bail out.
	 */
	if (!uac_v2v3_control_is_readable(hdr->bmControls,
				      UAC2_CS_CONTROL_CLOCK_VALID))
		return 0;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (!cval)
		return -ENOMEM;

	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, hdr->bClockID);

	cval->min = 0;
	cval->max = 1;
	cval->channels = 1;
	cval->val_type = USB_MIXER_BOOLEAN;
	cval->control = UAC2_CS_CONTROL_CLOCK_VALID;

	cval->master_readonly = 1;
	/* From UAC2 5.2.5.1.2 "Only the get request is supported." */
	kctl = snd_ctl_new1(&usb_bool_master_control_ctl_ro, cval);

	if (!kctl) {
		usb_mixer_elem_info_free(cval);
		return -ENOMEM;
	}

	kctl->private_free = snd_usb_mixer_elem_free;
	ret = snd_usb_copy_string_desc(state->chip, hdr->iClockSource,
				       name, sizeof(name));
	if (ret > 0)
		snprintf(kctl->id.name, sizeof(kctl->id.name),
			 "%s Validity", name);
	else
		snprintf(kctl->id.name, sizeof(kctl->id.name),
			 "Clock Source %d Validity", hdr->bClockID);

	return snd_usb_mixer_add_control(&cval->head, kctl);
}

/*
 * parse a feature unit
 *
 * most of controls are defined here.
 */
static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
				    void *_ftr)
{
	int channels, i, j;
	struct usb_audio_term iterm;
	unsigned int master_bits;
	int err, csize;
	struct uac_feature_unit_descriptor *hdr = _ftr;
	__u8 *bmaControls;

	if (state->mixer->protocol == UAC_VERSION_1) {
		csize = hdr->bControlSize;
		channels = (hdr->bLength - 7) / csize - 1;
		bmaControls = hdr->bmaControls;
	} else if (state->mixer->protocol == UAC_VERSION_2) {
		struct uac2_feature_unit_descriptor *ftr = _ftr;
		csize = 4;
		channels = (hdr->bLength - 6) / 4 - 1;
		bmaControls = ftr->bmaControls;
	} else { /* UAC_VERSION_3 */
		struct uac3_feature_unit_descriptor *ftr = _ftr;

		csize = 4;
		channels = (ftr->bLength - 7) / 4 - 1;
		bmaControls = ftr->bmaControls;
	}

	/* parse the source unit */
	err = parse_audio_unit(state, hdr->bSourceID);
	if (err < 0)
		return err;

	/* determine the input source type and name */
	err = check_input_term(state, hdr->bSourceID, &iterm);
	if (err < 0)
		return err;

	master_bits = snd_usb_combine_bytes(bmaControls, csize);
	/* master configuration quirks */
	switch (state->chip->usb_id) {
	case USB_ID(0x08bb, 0x2702):
		usb_audio_info(state->chip,
			       "usbmixer: master volume quirk for PCM2702 chip\n");
		/* disable non-functional volume control */
		master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
		break;
	case USB_ID(0x1130, 0xf211):
		usb_audio_info(state->chip,
			       "usbmixer: volume control quirk for Tenx TP6911 Audio Headset\n");
		/* disable non-functional volume control */
		channels = 0;
		break;

	}

	if (state->mixer->protocol == UAC_VERSION_1) {
		/* check all control types */
		for (i = 0; i < 10; i++) {
			unsigned int ch_bits = 0;
			int control = audio_feature_info[i].control;

			for (j = 0; j < channels; j++) {
				unsigned int mask;

				mask = snd_usb_combine_bytes(bmaControls +
							     csize * (j+1), csize);
				if (mask & (1 << i))
					ch_bits |= (1 << j);
			}
			/* audio class v1 controls are never read-only */

			/*
			 * The first channel must be set
			 * (for ease of programming).
			 */
			if (ch_bits & 1)
				build_feature_ctl(state, _ftr, ch_bits, control,
						  &iterm, unitid, 0);
			if (master_bits & (1 << i))
				build_feature_ctl(state, _ftr, 0, control,
						  &iterm, unitid, 0);
		}
	} else { /* UAC_VERSION_2/3 */
		for (i = 0; i < ARRAY_SIZE(audio_feature_info); i++) {
			unsigned int ch_bits = 0;
			unsigned int ch_read_only = 0;
			int control = audio_feature_info[i].control;

			for (j = 0; j < channels; j++) {
				unsigned int mask;

				mask = snd_usb_combine_bytes(bmaControls +
							     csize * (j+1), csize);
				if (uac_v2v3_control_is_readable(mask, control)) {
					ch_bits |= (1 << j);
					if (!uac_v2v3_control_is_writeable(mask, control))
						ch_read_only |= (1 << j);
				}
			}

			/*
			 * NOTE: build_feature_ctl() will mark the control
			 * read-only if all channels are marked read-only in
			 * the descriptors. Otherwise, the control will be
			 * reported as writeable, but the driver will not
			 * actually issue a write command for read-only
			 * channels.
			 */

			/*
			 * The first channel must be set
			 * (for ease of programming).
			 */
			if (ch_bits & 1)
				build_feature_ctl(state, _ftr, ch_bits, control,
						  &iterm, unitid, ch_read_only);
			if (uac_v2v3_control_is_readable(master_bits, control))
				build_feature_ctl(state, _ftr, 0, control,
						  &iterm, unitid,
						  !uac_v2v3_control_is_writeable(master_bits,
										 control));
		}
	}

	return 0;
}

/*
 * Mixer Unit
 */

/* check whether the given in/out overflows bmMixerControls matrix */
static bool mixer_bitmap_overflow(struct uac_mixer_unit_descriptor *desc,
				  int protocol, int num_ins, int num_outs)
{
	u8 *hdr = (u8 *)desc;
	u8 *c = uac_mixer_unit_bmControls(desc, protocol);
	size_t rest; /* remaining bytes after bmMixerControls */

	switch (protocol) {
	case UAC_VERSION_1:
	default:
		rest = 1; /* iMixer */
		break;
	case UAC_VERSION_2:
		rest = 2; /* bmControls + iMixer */
		break;
	case UAC_VERSION_3:
		rest = 6; /* bmControls + wMixerDescrStr */
		break;
	}

	/* overflow? */
	return c + (num_ins * num_outs + 7) / 8 + rest > hdr + hdr[0];
}

/*
 * build a mixer unit control
 *
 * the callbacks are identical with feature unit.
 * input channel number (zero based) is given in control field instead.
 */
static void build_mixer_unit_ctl(struct mixer_build *state,
				 struct uac_mixer_unit_descriptor *desc,
				 int in_pin, int in_ch, int num_outs,
				 int unitid, struct usb_audio_term *iterm)
{
	struct usb_mixer_elem_info *cval;
	unsigned int i, len;
	struct snd_kcontrol *kctl;
	const struct usbmix_name_map *map;

	map = find_map(state->map, unitid, 0);
	if (check_ignored_ctl(map))
		return;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (!cval)
		return;

	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
	cval->control = in_ch + 1; /* based on 1 */
	cval->val_type = USB_MIXER_S16;
	for (i = 0; i < num_outs; i++) {
		__u8 *c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);

		if (check_matrix_bitmap(c, in_ch, i, num_outs)) {
			cval->cmask |= (1 << i);
			cval->channels++;
		}
	}

	/* get min/max values */
	get_min_max(cval, 0);

	kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
	if (!kctl) {
		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
		usb_mixer_elem_info_free(cval);
		return;
	}
	kctl->private_free = snd_usb_mixer_elem_free;

	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
	if (!len)
		len = get_term_name(state->chip, iterm, kctl->id.name,
				    sizeof(kctl->id.name), 0);
	if (!len)
		len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
	append_ctl_name(kctl, " Volume");

	usb_audio_dbg(state->chip, "[%d] MU [%s] ch = %d, val = %d/%d\n",
		    cval->head.id, kctl->id.name, cval->channels, cval->min, cval->max);
	snd_usb_mixer_add_control(&cval->head, kctl);
}

static int parse_audio_input_terminal(struct mixer_build *state, int unitid,
				      void *raw_desc)
{
	struct usb_audio_term iterm;
	unsigned int control, bmctls, term_id;

	if (state->mixer->protocol == UAC_VERSION_2) {
		struct uac2_input_terminal_descriptor *d_v2 = raw_desc;
		control = UAC2_TE_CONNECTOR;
		term_id = d_v2->bTerminalID;
		bmctls = le16_to_cpu(d_v2->bmControls);
	} else if (state->mixer->protocol == UAC_VERSION_3) {
		struct uac3_input_terminal_descriptor *d_v3 = raw_desc;
		control = UAC3_TE_INSERTION;
		term_id = d_v3->bTerminalID;
		bmctls = le32_to_cpu(d_v3->bmControls);
	} else {
		return 0; /* UAC1. No Insertion control */
	}

	check_input_term(state, term_id, &iterm);

	/* Check for jack detection. */
	if (uac_v2v3_control_is_readable(bmctls, control))
		build_connector_control(state->mixer, &iterm, true);

	return 0;
}

/*
 * parse a mixer unit
 */
static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
				  void *raw_desc)
{
	struct uac_mixer_unit_descriptor *desc = raw_desc;
	struct usb_audio_term iterm;
	int input_pins, num_ins, num_outs;
	int pin, ich, err;

	err = uac_mixer_unit_get_channels(state, desc);
	if (err < 0) {
		usb_audio_err(state->chip,
			      "invalid MIXER UNIT descriptor %d\n",
			      unitid);
		return err;
	}

	num_outs = err;
	input_pins = desc->bNrInPins;

	num_ins = 0;
	ich = 0;
	for (pin = 0; pin < input_pins; pin++) {
		err = parse_audio_unit(state, desc->baSourceID[pin]);
		if (err < 0)
			continue;
		/* no bmControls field (e.g. Maya44) -> ignore */
		if (!num_outs)
			continue;
		err = check_input_term(state, desc->baSourceID[pin], &iterm);
		if (err < 0)
			return err;
		num_ins += iterm.channels;
		if (mixer_bitmap_overflow(desc, state->mixer->protocol,
					  num_ins, num_outs))
			break;
		for (; ich < num_ins; ich++) {
			int och, ich_has_controls = 0;

			for (och = 0; och < num_outs; och++) {
				__u8 *c = uac_mixer_unit_bmControls(desc,
						state->mixer->protocol);

				if (check_matrix_bitmap(c, ich, och, num_outs)) {
					ich_has_controls = 1;
					break;
				}
			}
			if (ich_has_controls)
				build_mixer_unit_ctl(state, desc, pin, ich, num_outs,
						     unitid, &iterm);
		}
	}
	return 0;
}

/*
 * Processing Unit / Extension Unit
 */

/* get callback for processing/extension unit */
static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol,
				  struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int err, val;

	err = get_cur_ctl_value(cval, cval->control << 8, &val);
	if (err < 0) {
		ucontrol->value.integer.value[0] = cval->min;
		return filter_error(cval, err);
	}
	val = get_relative_value(cval, val);
	ucontrol->value.integer.value[0] = val;
	return 0;
}

/* put callback for processing/extension unit */
static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol,
				  struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int val, oval, err;

	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
	if (err < 0)
		return filter_error(cval, err);
	val = ucontrol->value.integer.value[0];
	val = get_abs_value(cval, val);
	if (val != oval) {
		set_cur_ctl_value(cval, cval->control << 8, val);
		return 1;
	}
	return 0;
}

/* alsa control interface for processing/extension unit */
static const struct snd_kcontrol_new mixer_procunit_ctl = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "", /* will be filled later */
	.info = mixer_ctl_feature_info,
	.get = mixer_ctl_procunit_get,
	.put = mixer_ctl_procunit_put,
};

/*
 * predefined data for processing units
 */
struct procunit_value_info {
	int control;
	char *suffix;
	int val_type;
	int min_value;
};

struct procunit_info {
	int type;
	char *name;
	struct procunit_value_info *values;
};

static struct procunit_value_info undefined_proc_info[] = {
	{ 0x00, "Control Undefined", 0 },
	{ 0 }
};

static struct procunit_value_info updown_proc_info[] = {
	{ UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
	{ UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
	{ 0 }
};
static struct procunit_value_info prologic_proc_info[] = {
	{ UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
	{ UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
	{ 0 }
};
static struct procunit_value_info threed_enh_proc_info[] = {
	{ UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
	{ UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
	{ 0 }
};
static struct procunit_value_info reverb_proc_info[] = {
	{ UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
	{ UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
	{ UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
	{ UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
	{ 0 }
};
static struct procunit_value_info chorus_proc_info[] = {
	{ UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
	{ UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
	{ UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
	{ UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
	{ 0 }
};
static struct procunit_value_info dcr_proc_info[] = {
	{ UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
	{ UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
	{ UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
	{ UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
	{ UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
	{ UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
	{ 0 }
};

static struct procunit_info procunits[] = {
	{ UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
	{ UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
	{ UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
	{ UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
	{ UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
	{ UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
	{ 0 },
};

static struct procunit_value_info uac3_updown_proc_info[] = {
	{ UAC3_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
	{ 0 }
};
static struct procunit_value_info uac3_stereo_ext_proc_info[] = {
	{ UAC3_EXT_WIDTH_CONTROL, "Width Control", USB_MIXER_U8 },
	{ 0 }
};

static struct procunit_info uac3_procunits[] = {
	{ UAC3_PROCESS_UP_DOWNMIX, "Up Down", uac3_updown_proc_info },
	{ UAC3_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", uac3_stereo_ext_proc_info },
	{ UAC3_PROCESS_MULTI_FUNCTION, "Multi-Function", undefined_proc_info },
	{ 0 },
};

/*
 * predefined data for extension units
 */
static struct procunit_value_info clock_rate_xu_info[] = {
	{ USB_XU_CLOCK_RATE_SELECTOR, "Selector", USB_MIXER_U8, 0 },
	{ 0 }
};
static struct procunit_value_info clock_source_xu_info[] = {
	{ USB_XU_CLOCK_SOURCE_SELECTOR, "External", USB_MIXER_BOOLEAN },
	{ 0 }
};
static struct procunit_value_info spdif_format_xu_info[] = {
	{ USB_XU_DIGITAL_FORMAT_SELECTOR, "SPDIF/AC3", USB_MIXER_BOOLEAN },
	{ 0 }
};
static struct procunit_value_info soft_limit_xu_info[] = {
	{ USB_XU_SOFT_LIMIT_SELECTOR, " ", USB_MIXER_BOOLEAN },
	{ 0 }
};
static struct procunit_info extunits[] = {
	{ USB_XU_CLOCK_RATE, "Clock rate", clock_rate_xu_info },
	{ USB_XU_CLOCK_SOURCE, "DigitalIn CLK source", clock_source_xu_info },
	{ USB_XU_DIGITAL_IO_STATUS, "DigitalOut format:", spdif_format_xu_info },
	{ USB_XU_DEVICE_OPTIONS, "AnalogueIn Soft Limit", soft_limit_xu_info },
	{ 0 }
};

/*
 * build a processing/extension unit
 */
static int build_audio_procunit(struct mixer_build *state, int unitid,
				void *raw_desc, struct procunit_info *list,
				bool extension_unit)
{
	struct uac_processing_unit_descriptor *desc = raw_desc;
	int num_ins;
	struct usb_mixer_elem_info *cval;
	struct snd_kcontrol *kctl;
	int i, err, nameid, type, len;
	struct procunit_info *info;
	struct procunit_value_info *valinfo;
	const struct usbmix_name_map *map;
	static struct procunit_value_info default_value_info[] = {
		{ 0x01, "Switch", USB_MIXER_BOOLEAN },
		{ 0 }
	};
	static struct procunit_info default_info = {
		0, NULL, default_value_info
	};
	const char *name = extension_unit ?
		"Extension Unit" : "Processing Unit";

	num_ins = desc->bNrInPins;
	for (i = 0; i < num_ins; i++) {
		err = parse_audio_unit(state, desc->baSourceID[i]);
		if (err < 0)
			return err;
	}

	type = le16_to_cpu(desc->wProcessType);
	for (info = list; info && info->type; info++)
		if (info->type == type)
			break;
	if (!info || !info->type)
		info = &default_info;

	for (valinfo = info->values; valinfo->control; valinfo++) {
		__u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);

		if (state->mixer->protocol == UAC_VERSION_1) {
			if (!(controls[valinfo->control / 8] &
					(1 << ((valinfo->control % 8) - 1))))
				continue;
		} else { /* UAC_VERSION_2/3 */
			if (!uac_v2v3_control_is_readable(controls[valinfo->control / 8],
							  valinfo->control))
				continue;
		}

		map = find_map(state->map, unitid, valinfo->control);
		if (check_ignored_ctl(map))
			continue;
		cval = kzalloc(sizeof(*cval), GFP_KERNEL);
		if (!cval)
			return -ENOMEM;
		snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
		cval->control = valinfo->control;
		cval->val_type = valinfo->val_type;
		cval->channels = 1;

		if (state->mixer->protocol > UAC_VERSION_1 &&
		    !uac_v2v3_control_is_writeable(controls[valinfo->control / 8],
						   valinfo->control))
			cval->master_readonly = 1;

		/* get min/max values */
		switch (type) {
		case UAC_PROCESS_UP_DOWNMIX: {
			bool mode_sel = false;

			switch (state->mixer->protocol) {
			case UAC_VERSION_1:
			case UAC_VERSION_2:
			default:
				if (cval->control == UAC_UD_MODE_SELECT)
					mode_sel = true;
				break;
			case UAC_VERSION_3:
				if (cval->control == UAC3_UD_MODE_SELECT)
					mode_sel = true;
				break;
			}

			if (mode_sel) {
				__u8 *control_spec = uac_processing_unit_specific(desc,
								state->mixer->protocol);
				cval->min = 1;
				cval->max = control_spec[0];
				cval->res = 1;
				cval->initialized = 1;
				break;
			}

			get_min_max(cval, valinfo->min_value);
			break;
		}
		case USB_XU_CLOCK_RATE:
			/*
			 * E-Mu USB 0404/0202/TrackerPre/0204
			 * samplerate control quirk
			 */
			cval->min = 0;
			cval->max = 5;
			cval->res = 1;
			cval->initialized = 1;
			break;
		default:
			get_min_max(cval, valinfo->min_value);
			break;
		}

		kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
		if (!kctl) {
			usb_mixer_elem_info_free(cval);
			return -ENOMEM;
		}
		kctl->private_free = snd_usb_mixer_elem_free;

		if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name))) {
			/* nothing */ ;
		} else if (info->name) {
			strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
		} else {
			if (extension_unit)
				nameid = uac_extension_unit_iExtension(desc, state->mixer->protocol);
			else
				nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
			len = 0;
			if (nameid)
				len = snd_usb_copy_string_desc(state->chip,
							       nameid,
							       kctl->id.name,
							       sizeof(kctl->id.name));
			if (!len)
				strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
		}
		append_ctl_name(kctl, " ");
		append_ctl_name(kctl, valinfo->suffix);

		usb_audio_dbg(state->chip,
			      "[%d] PU [%s] ch = %d, val = %d/%d\n",
			      cval->head.id, kctl->id.name, cval->channels,
			      cval->min, cval->max);

		err = snd_usb_mixer_add_control(&cval->head, kctl);
		if (err < 0)
			return err;
	}
	return 0;
}

static int parse_audio_processing_unit(struct mixer_build *state, int unitid,
				       void *raw_desc)
{
	switch (state->mixer->protocol) {
	case UAC_VERSION_1:
	case UAC_VERSION_2:
	default:
		return build_audio_procunit(state, unitid, raw_desc,
					    procunits, false);
	case UAC_VERSION_3:
		return build_audio_procunit(state, unitid, raw_desc,
					    uac3_procunits, false);
	}
}

static int parse_audio_extension_unit(struct mixer_build *state, int unitid,
				      void *raw_desc)
{
	/*
	 * Note that we parse extension units with processing unit descriptors.
	 * That's ok as the layout is the same.
	 */
	return build_audio_procunit(state, unitid, raw_desc, extunits, true);
}

/*
 * Selector Unit
 */

/*
 * info callback for selector unit
 * use an enumerator type for routing
 */
static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol,
				   struct snd_ctl_elem_info *uinfo)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	const char **itemlist = (const char **)kcontrol->private_value;

	if (snd_BUG_ON(!itemlist))
		return -EINVAL;
	return snd_ctl_enum_info(uinfo, 1, cval->max, itemlist);
}

/* get callback for selector unit */
static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol,
				  struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int val, err;

	err = get_cur_ctl_value(cval, cval->control << 8, &val);
	if (err < 0) {
		ucontrol->value.enumerated.item[0] = 0;
		return filter_error(cval, err);
	}
	val = get_relative_value(cval, val);
	ucontrol->value.enumerated.item[0] = val;
	return 0;
}

/* put callback for selector unit */
static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol,
				  struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_elem_info *cval = kcontrol->private_data;
	int val, oval, err;

	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
	if (err < 0)
		return filter_error(cval, err);
	val = ucontrol->value.enumerated.item[0];
	val = get_abs_value(cval, val);
	if (val != oval) {
		set_cur_ctl_value(cval, cval->control << 8, val);
		return 1;
	}
	return 0;
}

/* alsa control interface for selector unit */
static const struct snd_kcontrol_new mixer_selectunit_ctl = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "", /* will be filled later */
	.info = mixer_ctl_selector_info,
	.get = mixer_ctl_selector_get,
	.put = mixer_ctl_selector_put,
};

/*
 * private free callback.
 * free both private_data and private_value
 */
static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
{
	int i, num_ins = 0;

	if (kctl->private_data) {
		struct usb_mixer_elem_info *cval = kctl->private_data;
		num_ins = cval->max;
		usb_mixer_elem_info_free(cval);
		kctl->private_data = NULL;
	}
	if (kctl->private_value) {
		char **itemlist = (char **)kctl->private_value;
		for (i = 0; i < num_ins; i++)
			kfree(itemlist[i]);
		kfree(itemlist);
		kctl->private_value = 0;
	}
}

/*
 * parse a selector unit
 */
static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
				     void *raw_desc)
{
	struct uac_selector_unit_descriptor *desc = raw_desc;
	unsigned int i, nameid, len;
	int err;
	struct usb_mixer_elem_info *cval;
	struct snd_kcontrol *kctl;
	const struct usbmix_name_map *map;
	char **namelist;

	for (i = 0; i < desc->bNrInPins; i++) {
		err = parse_audio_unit(state, desc->baSourceID[i]);
		if (err < 0)
			return err;
	}

	if (desc->bNrInPins == 1) /* only one ? nonsense! */
		return 0;

	map = find_map(state->map, unitid, 0);
	if (check_ignored_ctl(map))
		return 0;

	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
	if (!cval)
		return -ENOMEM;
	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
	cval->val_type = USB_MIXER_U8;
	cval->channels = 1;
	cval->min = 1;
	cval->max = desc->bNrInPins;
	cval->res = 1;
	cval->initialized = 1;

	switch (state->mixer->protocol) {
	case UAC_VERSION_1:
	default:
		cval->control = 0;
		break;
	case UAC_VERSION_2:
	case UAC_VERSION_3:
		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
			cval->control = UAC2_CX_CLOCK_SELECTOR;
		else /* UAC2/3_SELECTOR_UNIT */
			cval->control = UAC2_SU_SELECTOR;
		break;
	}

	namelist = kcalloc(desc->bNrInPins, sizeof(char *), GFP_KERNEL);
	if (!namelist) {
		err = -ENOMEM;
		goto error_cval;
	}
#define MAX_ITEM_NAME_LEN	64
	for (i = 0; i < desc->bNrInPins; i++) {
		struct usb_audio_term iterm;
		len = 0;
		namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
		if (!namelist[i]) {
			err = -ENOMEM;
			goto error_name;
		}
		len = check_mapped_selector_name(state, unitid, i, namelist[i],
						 MAX_ITEM_NAME_LEN);
		if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
			len = get_term_name(state->chip, &iterm, namelist[i],
					    MAX_ITEM_NAME_LEN, 0);
		if (! len)
			sprintf(namelist[i], "Input %u", i);
	}

	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
	if (! kctl) {
		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
		err = -ENOMEM;
		goto error_name;
	}
	kctl->private_value = (unsigned long)namelist;
	kctl->private_free = usb_mixer_selector_elem_free;

	/* check the static mapping table at first */
	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
	if (!len) {
		/* no mapping ? */
		switch (state->mixer->protocol) {
		case UAC_VERSION_1:
		case UAC_VERSION_2:
		default:
		/* if iSelector is given, use it */
			nameid = uac_selector_unit_iSelector(desc);
			if (nameid)
				len = snd_usb_copy_string_desc(state->chip,
							nameid, kctl->id.name,
							sizeof(kctl->id.name));
			break;
		case UAC_VERSION_3:
			/* TODO: Class-Specific strings not yet supported */
			break;
		}

		/* ... or pick up the terminal name at next */
		if (!len)
			len = get_term_name(state->chip, &state->oterm,
				    kctl->id.name, sizeof(kctl->id.name), 0);
		/* ... or use the fixed string "USB" as the last resort */
		if (!len)
			strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));

		/* and add the proper suffix */
		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
			append_ctl_name(kctl, " Clock Source");
		else if ((state->oterm.type & 0xff00) == 0x0100)
			append_ctl_name(kctl, " Capture Source");
		else
			append_ctl_name(kctl, " Playback Source");
	}

	usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
		    cval->head.id, kctl->id.name, desc->bNrInPins);
	return snd_usb_mixer_add_control(&cval->head, kctl);

 error_name:
	for (i = 0; i < desc->bNrInPins; i++)
		kfree(namelist[i]);
	kfree(namelist);
 error_cval:
	usb_mixer_elem_info_free(cval);
	return err;
}

/*
 * parse an audio unit recursively
 */

static int parse_audio_unit(struct mixer_build *state, int unitid)
{
	unsigned char *p1;
	int protocol = state->mixer->protocol;

	if (test_and_set_bit(unitid, state->unitbitmap))
		return 0; /* the unit already visited */

	p1 = find_audio_control_unit(state, unitid);
	if (!p1) {
		usb_audio_err(state->chip, "unit %d not found!\n", unitid);
		return -EINVAL;
	}

	if (!snd_usb_validate_audio_desc(p1, protocol)) {
		usb_audio_dbg(state->chip, "invalid unit %d\n", unitid);
		return 0; /* skip invalid unit */
	}

	switch (PTYPE(protocol, p1[2])) {
	case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):
	case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):
	case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):
		return parse_audio_input_terminal(state, unitid, p1);
	case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):
	case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):
	case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):
		return parse_audio_mixer_unit(state, unitid, p1);
	case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):
	case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):
		return parse_clock_source_unit(state, unitid, p1);
	case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):
	case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):
	case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):
	case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):
	case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):
		return parse_audio_selector_unit(state, unitid, p1);
	case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):
	case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):
	case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT):
		return parse_audio_feature_unit(state, unitid, p1);
	case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):
	case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):
	case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):
		return parse_audio_processing_unit(state, unitid, p1);
	case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):
	case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):
	case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):
		return parse_audio_extension_unit(state, unitid, p1);
	case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):
	case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):
		return 0; /* FIXME - effect units not implemented yet */
	default:
		usb_audio_err(state->chip,
			      "unit %u: unexpected type 0x%02x\n",
			      unitid, p1[2]);
		return -EINVAL;
	}
}

static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
{
	/* kill pending URBs */
	snd_usb_mixer_disconnect(mixer);

	kfree(mixer->id_elems);
	if (mixer->urb) {
		kfree(mixer->urb->transfer_buffer);
		usb_free_urb(mixer->urb);
	}
	usb_free_urb(mixer->rc_urb);
	kfree(mixer->rc_setup_packet);
	kfree(mixer);
}

static int snd_usb_mixer_dev_free(struct snd_device *device)
{
	struct usb_mixer_interface *mixer = device->device_data;
	snd_usb_mixer_free(mixer);
	return 0;
}

/* UAC3 predefined channels configuration */
struct uac3_badd_profile {
	int subclass;
	const char *name;
	int c_chmask;	/* capture channels mask */
	int p_chmask;	/* playback channels mask */
	int st_chmask;	/* side tone mixing channel mask */
};

static struct uac3_badd_profile uac3_badd_profiles[] = {
	{
		/*
		 * BAIF, BAOF or combination of both
		 * IN: Mono or Stereo cfg, Mono alt possible
		 * OUT: Mono or Stereo cfg, Mono alt possible
		 */
		.subclass = UAC3_FUNCTION_SUBCLASS_GENERIC_IO,
		.name = "GENERIC IO",
		.c_chmask = -1,		/* dynamic channels */
		.p_chmask = -1,		/* dynamic channels */
	},
	{
		/* BAOF; Stereo only cfg, Mono alt possible */
		.subclass = UAC3_FUNCTION_SUBCLASS_HEADPHONE,
		.name = "HEADPHONE",
		.p_chmask = 3,
	},
	{
		/* BAOF; Mono or Stereo cfg, Mono alt possible */
		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKER,
		.name = "SPEAKER",
		.p_chmask = -1,		/* dynamic channels */
	},
	{
		/* BAIF; Mono or Stereo cfg, Mono alt possible */
		.subclass = UAC3_FUNCTION_SUBCLASS_MICROPHONE,
		.name = "MICROPHONE",
		.c_chmask = -1,		/* dynamic channels */
	},
	{
		/*
		 * BAIOF topology
		 * IN: Mono only
		 * OUT: Mono or Stereo cfg, Mono alt possible
		 */
		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET,
		.name = "HEADSET",
		.c_chmask = 1,
		.p_chmask = -1,		/* dynamic channels */
		.st_chmask = 1,
	},
	{
		/* BAIOF; IN: Mono only; OUT: Stereo only, Mono alt possible */
		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER,
		.name = "HEADSET ADAPTER",
		.c_chmask = 1,
		.p_chmask = 3,
		.st_chmask = 1,
	},
	{
		/* BAIF + BAOF; IN: Mono only; OUT: Mono only */
		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE,
		.name = "SPEAKERPHONE",
		.c_chmask = 1,
		.p_chmask = 1,
	},
	{ 0 } /* terminator */
};

static bool uac3_badd_func_has_valid_channels(struct usb_mixer_interface *mixer,
					      struct uac3_badd_profile *f,
					      int c_chmask, int p_chmask)
{
	/*
	 * If both playback/capture channels are dynamic, make sure
	 * at least one channel is present
	 */
	if (f->c_chmask < 0 && f->p_chmask < 0) {
		if (!c_chmask && !p_chmask) {
			usb_audio_warn(mixer->chip, "BAAD %s: no channels?",
				       f->name);
			return false;
		}
		return true;
	}

	if ((f->c_chmask < 0 && !c_chmask) ||
	    (f->c_chmask >= 0 && f->c_chmask != c_chmask)) {
		usb_audio_warn(mixer->chip, "BAAD %s c_chmask mismatch",
			       f->name);
		return false;
	}
	if ((f->p_chmask < 0 && !p_chmask) ||
	    (f->p_chmask >= 0 && f->p_chmask != p_chmask)) {
		usb_audio_warn(mixer->chip, "BAAD %s p_chmask mismatch",
			       f->name);
		return false;
	}
	return true;
}

/*
 * create mixer controls for UAC3 BADD profiles
 *
 * UAC3 BADD device doesn't contain CS descriptors thus we will guess everything
 *
 * BADD device may contain Mixer Unit, which doesn't have any controls, skip it
 */
static int snd_usb_mixer_controls_badd(struct usb_mixer_interface *mixer,
				       int ctrlif)
{
	struct usb_device *dev = mixer->chip->dev;
	struct usb_interface_assoc_descriptor *assoc;
	int badd_profile = mixer->chip->badd_profile;
	struct uac3_badd_profile *f;
	const struct usbmix_ctl_map *map;
	int p_chmask = 0, c_chmask = 0, st_chmask = 0;
	int i;

	assoc = usb_ifnum_to_if(dev, ctrlif)->intf_assoc;

	/* Detect BADD capture/playback channels from AS EP descriptors */
	for (i = 0; i < assoc->bInterfaceCount; i++) {
		int intf = assoc->bFirstInterface + i;

		struct usb_interface *iface;
		struct usb_host_interface *alts;
		struct usb_interface_descriptor *altsd;
		unsigned int maxpacksize;
		char dir_in;
		int chmask, num;

		if (intf == ctrlif)
			continue;

		iface = usb_ifnum_to_if(dev, intf);
		if (!iface)
			continue;

		num = iface->num_altsetting;

		if (num < 2)
			return -EINVAL;

		/*
		 * The number of Channels in an AudioStreaming interface
		 * and the audio sample bit resolution (16 bits or 24
		 * bits) can be derived from the wMaxPacketSize field in
		 * the Standard AS Audio Data Endpoint descriptor in
		 * Alternate Setting 1
		 */
		alts = &iface->altsetting[1];
		altsd = get_iface_desc(alts);

		if (altsd->bNumEndpoints < 1)
			return -EINVAL;

		/* check direction */
		dir_in = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN);
		maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);

		switch (maxpacksize) {
		default:
			usb_audio_err(mixer->chip,
				"incorrect wMaxPacketSize 0x%x for BADD profile\n",
				maxpacksize);
			return -EINVAL;
		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_16:
		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_16:
		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_24:
		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_24:
			chmask = 1;
			break;
		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_16:
		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_16:
		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_24:
		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_24:
			chmask = 3;
			break;
		}

		if (dir_in)
			c_chmask = chmask;
		else
			p_chmask = chmask;
	}

	usb_audio_dbg(mixer->chip,
		"UAC3 BADD profile 0x%x: detected c_chmask=%d p_chmask=%d\n",
		badd_profile, c_chmask, p_chmask);

	/* check the mapping table */
	for (map = uac3_badd_usbmix_ctl_maps; map->id; map++) {
		if (map->id == badd_profile)
			break;
	}

	if (!map->id)
		return -EINVAL;

	for (f = uac3_badd_profiles; f->name; f++) {
		if (badd_profile == f->subclass)
			break;
	}
	if (!f->name)
		return -EINVAL;
	if (!uac3_badd_func_has_valid_channels(mixer, f, c_chmask, p_chmask))
		return -EINVAL;
	st_chmask = f->st_chmask;

	/* Playback */
	if (p_chmask) {
		/* Master channel, always writable */
		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
				       UAC3_BADD_FU_ID2, map->map);
		/* Mono/Stereo volume channels, always writable */
		build_feature_ctl_badd(mixer, p_chmask, UAC_FU_VOLUME,
				       UAC3_BADD_FU_ID2, map->map);
	}

	/* Capture */
	if (c_chmask) {
		/* Master channel, always writable */
		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
				       UAC3_BADD_FU_ID5, map->map);
		/* Mono/Stereo volume channels, always writable */
		build_feature_ctl_badd(mixer, c_chmask, UAC_FU_VOLUME,
				       UAC3_BADD_FU_ID5, map->map);
	}

	/* Side tone-mixing */
	if (st_chmask) {
		/* Master channel, always writable */
		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
				       UAC3_BADD_FU_ID7, map->map);
		/* Mono volume channel, always writable */
		build_feature_ctl_badd(mixer, 1, UAC_FU_VOLUME,
				       UAC3_BADD_FU_ID7, map->map);
	}

	/* Insertion Control */
	if (f->subclass == UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER) {
		struct usb_audio_term iterm, oterm;

		/* Input Term - Insertion control */
		memset(&iterm, 0, sizeof(iterm));
		iterm.id = UAC3_BADD_IT_ID4;
		iterm.type = UAC_BIDIR_TERMINAL_HEADSET;
		build_connector_control(mixer, &iterm, true);

		/* Output Term - Insertion control */
		memset(&oterm, 0, sizeof(oterm));
		oterm.id = UAC3_BADD_OT_ID3;
		oterm.type = UAC_BIDIR_TERMINAL_HEADSET;
		build_connector_control(mixer, &oterm, false);
	}

	return 0;
}

/*
 * create mixer controls
 *
 * walk through all UAC_OUTPUT_TERMINAL descriptors to search for mixers
 */
static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
{
	struct mixer_build state;
	int err;
	const struct usbmix_ctl_map *map;
	void *p;

	memset(&state, 0, sizeof(state));
	state.chip = mixer->chip;
	state.mixer = mixer;
	state.buffer = mixer->hostif->extra;
	state.buflen = mixer->hostif->extralen;

	/* check the mapping table */
	for (map = usbmix_ctl_maps; map->id; map++) {
		if (map->id == state.chip->usb_id) {
			state.map = map->map;
			state.selector_map = map->selector_map;
			mixer->ignore_ctl_error = map->ignore_ctl_error;
			break;
		}
	}

	p = NULL;
	while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
					    mixer->hostif->extralen,
					    p, UAC_OUTPUT_TERMINAL)) != NULL) {
		if (!snd_usb_validate_audio_desc(p, mixer->protocol))
			continue; /* skip invalid descriptor */

		if (mixer->protocol == UAC_VERSION_1) {
			struct uac1_output_terminal_descriptor *desc = p;

			/* mark terminal ID as visited */
			set_bit(desc->bTerminalID, state.unitbitmap);
			state.oterm.id = desc->bTerminalID;
			state.oterm.type = le16_to_cpu(desc->wTerminalType);
			state.oterm.name = desc->iTerminal;
			err = parse_audio_unit(&state, desc->bSourceID);
			if (err < 0 && err != -EINVAL)
				return err;
		} else if (mixer->protocol == UAC_VERSION_2) {
			struct uac2_output_terminal_descriptor *desc = p;

			/* mark terminal ID as visited */
			set_bit(desc->bTerminalID, state.unitbitmap);
			state.oterm.id = desc->bTerminalID;
			state.oterm.type = le16_to_cpu(desc->wTerminalType);
			state.oterm.name = desc->iTerminal;
			err = parse_audio_unit(&state, desc->bSourceID);
			if (err < 0 && err != -EINVAL)
				return err;

			/*
			 * For UAC2, use the same approach to also add the
			 * clock selectors
			 */
			err = parse_audio_unit(&state, desc->bCSourceID);
			if (err < 0 && err != -EINVAL)
				return err;

			if (uac_v2v3_control_is_readable(le16_to_cpu(desc->bmControls),
							 UAC2_TE_CONNECTOR)) {
				build_connector_control(state.mixer, &state.oterm,
							false);
			}
		} else {  /* UAC_VERSION_3 */
			struct uac3_output_terminal_descriptor *desc = p;

			/* mark terminal ID as visited */
			set_bit(desc->bTerminalID, state.unitbitmap);
			state.oterm.id = desc->bTerminalID;
			state.oterm.type = le16_to_cpu(desc->wTerminalType);
			state.oterm.name = le16_to_cpu(desc->wTerminalDescrStr);
			err = parse_audio_unit(&state, desc->bSourceID);
			if (err < 0 && err != -EINVAL)
				return err;

			/*
			 * For UAC3, use the same approach to also add the
			 * clock selectors
			 */
			err = parse_audio_unit(&state, desc->bCSourceID);
			if (err < 0 && err != -EINVAL)
				return err;

			if (uac_v2v3_control_is_readable(le32_to_cpu(desc->bmControls),
							 UAC3_TE_INSERTION)) {
				build_connector_control(state.mixer, &state.oterm,
							false);
			}
		}
	}

	return 0;
}

void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
{
	struct usb_mixer_elem_list *list;

	for_each_mixer_elem(list, mixer, unitid) {
		struct usb_mixer_elem_info *info =
			mixer_elem_list_to_info(list);
		/* invalidate cache, so the value is read from the device */
		info->cached = 0;
		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
			       &list->kctl->id);
	}
}

static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
				    struct usb_mixer_elem_list *list)
{
	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
	static char *val_types[] = {"BOOLEAN", "INV_BOOLEAN",
				    "S8", "U8", "S16", "U16"};
	snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
			    "channels=%i, type=\"%s\"\n", cval->head.id,
			    cval->control, cval->cmask, cval->channels,
			    val_types[cval->val_type]);
	snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
			    cval->min, cval->max, cval->dBmin, cval->dBmax);
}

static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
				    struct snd_info_buffer *buffer)
{
	struct snd_usb_audio *chip = entry->private_data;
	struct usb_mixer_interface *mixer;
	struct usb_mixer_elem_list *list;
	int unitid;

	list_for_each_entry(mixer, &chip->mixer_list, list) {
		snd_iprintf(buffer,
			"USB Mixer: usb_id=0x%08x, ctrlif=%i, ctlerr=%i\n",
				chip->usb_id, snd_usb_ctrl_intf(chip),
				mixer->ignore_ctl_error);
		snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
		for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
			for_each_mixer_elem(list, mixer, unitid) {
				snd_iprintf(buffer, "  Unit: %i\n", list->id);
				if (list->kctl)
					snd_iprintf(buffer,
						    "    Control: name=\"%s\", index=%i\n",
						    list->kctl->id.name,
						    list->kctl->id.index);
				if (list->dump)
					list->dump(buffer, list);
			}
		}
	}
}

static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
				       int attribute, int value, int index)
{
	struct usb_mixer_elem_list *list;
	__u8 unitid = (index >> 8) & 0xff;
	__u8 control = (value >> 8) & 0xff;
	__u8 channel = value & 0xff;
	unsigned int count = 0;

	if (channel >= MAX_CHANNELS) {
		usb_audio_dbg(mixer->chip,
			"%s(): bogus channel number %d\n",
			__func__, channel);
		return;
	}

	for_each_mixer_elem(list, mixer, unitid)
		count++;

	if (count == 0)
		return;

	for_each_mixer_elem(list, mixer, unitid) {
		struct usb_mixer_elem_info *info;

		if (!list->kctl)
			continue;

		info = mixer_elem_list_to_info(list);
		if (count > 1 && info->control != control)
			continue;

		switch (attribute) {
		case UAC2_CS_CUR:
			/* invalidate cache, so the value is read from the device */
			if (channel)
				info->cached &= ~(1 << channel);
			else /* master channel */
				info->cached = 0;

			snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
				       &info->head.kctl->id);
			break;

		case UAC2_CS_RANGE:
			/* TODO */
			break;

		case UAC2_CS_MEM:
			/* TODO */
			break;

		default:
			usb_audio_dbg(mixer->chip,
				"unknown attribute %d in interrupt\n",
				attribute);
			break;
		} /* switch */
	}
}

static void snd_usb_mixer_interrupt(struct urb *urb)
{
	struct usb_mixer_interface *mixer = urb->context;
	int len = urb->actual_length;
	int ustatus = urb->status;

	if (ustatus != 0)
		goto requeue;

	if (mixer->protocol == UAC_VERSION_1) {
		struct uac1_status_word *status;

		for (status = urb->transfer_buffer;
		     len >= sizeof(*status);
		     len -= sizeof(*status), status++) {
			dev_dbg(&urb->dev->dev, "status interrupt: %02x %02x\n",
						status->bStatusType,
						status->bOriginator);

			/* ignore any notifications not from the control interface */
			if ((status->bStatusType & UAC1_STATUS_TYPE_ORIG_MASK) !=
				UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF)
				continue;

			if (status->bStatusType & UAC1_STATUS_TYPE_MEM_CHANGED)
				snd_usb_mixer_rc_memory_change(mixer, status->bOriginator);
			else
				snd_usb_mixer_notify_id(mixer, status->bOriginator);
		}
	} else { /* UAC_VERSION_2 */
		struct uac2_interrupt_data_msg *msg;

		for (msg = urb->transfer_buffer;
		     len >= sizeof(*msg);
		     len -= sizeof(*msg), msg++) {
			/* drop vendor specific and endpoint requests */
			if ((msg->bInfo & UAC2_INTERRUPT_DATA_MSG_VENDOR) ||
			    (msg->bInfo & UAC2_INTERRUPT_DATA_MSG_EP))
				continue;

			snd_usb_mixer_interrupt_v2(mixer, msg->bAttribute,
						   le16_to_cpu(msg->wValue),
						   le16_to_cpu(msg->wIndex));
		}
	}

requeue:
	if (ustatus != -ENOENT &&
	    ustatus != -ECONNRESET &&
	    ustatus != -ESHUTDOWN) {
		urb->dev = mixer->chip->dev;
		usb_submit_urb(urb, GFP_ATOMIC);
	}
}

/* create the handler for the optional status interrupt endpoint */
static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
{
	struct usb_endpoint_descriptor *ep;
	void *transfer_buffer;
	int buffer_length;
	unsigned int epnum;

	/* we need one interrupt input endpoint */
	if (get_iface_desc(mixer->hostif)->bNumEndpoints < 1)
		return 0;
	ep = get_endpoint(mixer->hostif, 0);
	if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_int(ep))
		return 0;

	epnum = usb_endpoint_num(ep);
	buffer_length = le16_to_cpu(ep->wMaxPacketSize);
	transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
	if (!transfer_buffer)
		return -ENOMEM;
	mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!mixer->urb) {
		kfree(transfer_buffer);
		return -ENOMEM;
	}
	usb_fill_int_urb(mixer->urb, mixer->chip->dev,
			 usb_rcvintpipe(mixer->chip->dev, epnum),
			 transfer_buffer, buffer_length,
			 snd_usb_mixer_interrupt, mixer, ep->bInterval);
	usb_submit_urb(mixer->urb, GFP_KERNEL);
	return 0;
}

static int keep_iface_ctl_get(struct snd_kcontrol *kcontrol,
			      struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);

	ucontrol->value.integer.value[0] = mixer->chip->keep_iface;
	return 0;
}

static int keep_iface_ctl_put(struct snd_kcontrol *kcontrol,
			      struct snd_ctl_elem_value *ucontrol)
{
	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
	bool keep_iface = !!ucontrol->value.integer.value[0];

	if (mixer->chip->keep_iface == keep_iface)
		return 0;
	mixer->chip->keep_iface = keep_iface;
	return 1;
}

static const struct snd_kcontrol_new keep_iface_ctl = {
	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
	.name = "Keep Interface",
	.info = snd_ctl_boolean_mono_info,
	.get = keep_iface_ctl_get,
	.put = keep_iface_ctl_put,
};

static int create_keep_iface_ctl(struct usb_mixer_interface *mixer)
{
	struct snd_kcontrol *kctl = snd_ctl_new1(&keep_iface_ctl, mixer);

	/* need only one control per card */
	if (snd_ctl_find_id(mixer->chip->card, &kctl->id)) {
		snd_ctl_free_one(kctl);
		return 0;
	}

	return snd_ctl_add(mixer->chip->card, kctl);
}

int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
			 int ignore_error)
{
	static struct snd_device_ops dev_ops = {
		.dev_free = snd_usb_mixer_dev_free
	};
	struct usb_mixer_interface *mixer;
	int err;

	strcpy(chip->card->mixername, "USB Mixer");

	mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
	if (!mixer)
		return -ENOMEM;
	mixer->chip = chip;
	mixer->ignore_ctl_error = ignore_error;
	mixer->id_elems = kcalloc(MAX_ID_ELEMS, sizeof(*mixer->id_elems),
				  GFP_KERNEL);
	if (!mixer->id_elems) {
		kfree(mixer);
		return -ENOMEM;
	}

	mixer->hostif = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
	switch (get_iface_desc(mixer->hostif)->bInterfaceProtocol) {
	case UAC_VERSION_1:
	default:
		mixer->protocol = UAC_VERSION_1;
		break;
	case UAC_VERSION_2:
		mixer->protocol = UAC_VERSION_2;
		break;
	case UAC_VERSION_3:
		mixer->protocol = UAC_VERSION_3;
		break;
	}

	if (mixer->protocol == UAC_VERSION_3 &&
			chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
		err = snd_usb_mixer_controls_badd(mixer, ctrlif);
		if (err < 0)
			goto _error;
	} else {
		err = snd_usb_mixer_controls(mixer);
		if (err < 0)
			goto _error;
	}

	err = snd_usb_mixer_status_create(mixer);
	if (err < 0)
		goto _error;

	err = create_keep_iface_ctl(mixer);
	if (err < 0)
		goto _error;

	err = snd_usb_mixer_apply_create_quirk(mixer);
	if (err < 0)
		goto _error;

	err = snd_device_new(chip->card, SNDRV_DEV_CODEC, mixer, &dev_ops);
	if (err < 0)
		goto _error;

	if (list_empty(&chip->mixer_list))
		snd_card_ro_proc_new(chip->card, "usbmixer", chip,
				     snd_usb_mixer_proc_read);

	list_add(&mixer->list, &chip->mixer_list);
	return 0;

_error:
	snd_usb_mixer_free(mixer);
	return err;
}

void snd_usb_mixer_disconnect(struct usb_mixer_interface *mixer)
{
	if (mixer->disconnected)
		return;
	if (mixer->urb)
		usb_kill_urb(mixer->urb);
	if (mixer->rc_urb)
		usb_kill_urb(mixer->rc_urb);
	if (mixer->private_free)
		mixer->private_free(mixer);
	mixer->disconnected = true;
}

#ifdef CONFIG_PM
/* stop any bus activity of a mixer */
static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
{
	usb_kill_urb(mixer->urb);
	usb_kill_urb(mixer->rc_urb);
}

static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
{
	int err;

	if (mixer->urb) {
		err = usb_submit_urb(mixer->urb, GFP_NOIO);
		if (err < 0)
			return err;
	}

	return 0;
}

int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
{
	snd_usb_mixer_inactivate(mixer);
	if (mixer->private_suspend)
		mixer->private_suspend(mixer);
	return 0;
}

static int restore_mixer_value(struct usb_mixer_elem_list *list)
{
	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
	int c, err, idx;

	if (cval->cmask) {
		idx = 0;
		for (c = 0; c < MAX_CHANNELS; c++) {
			if (!(cval->cmask & (1 << c)))
				continue;
			if (cval->cached & (1 << (c + 1))) {
				err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
							cval->cache_val[idx]);
				if (err < 0)
					return err;
			}
			idx++;
		}
	} else {
		/* master */
		if (cval->cached) {
			err = snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
			if (err < 0)
				return err;
		}
	}

	return 0;
}

int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume)
{
	struct usb_mixer_elem_list *list;
	int id, err;

	if (reset_resume) {
		/* restore cached mixer values */
		for (id = 0; id < MAX_ID_ELEMS; id++) {
			for_each_mixer_elem(list, mixer, id) {
				if (list->resume) {
					err = list->resume(list);
					if (err < 0)
						return err;
				}
			}
		}
	}

	snd_usb_mixer_resume_quirk(mixer);

	return snd_usb_mixer_activate(mixer);
}
#endif

void snd_usb_mixer_elem_init_std(struct usb_mixer_elem_list *list,
				 struct usb_mixer_interface *mixer,
				 int unitid)
{
	list->mixer = mixer;
	list->id = unitid;
	list->dump = snd_usb_mixer_dump_cval;
#ifdef CONFIG_PM
	list->resume = restore_mixer_value;
#endif
}