summaryrefslogtreecommitdiffstats
path: root/drivers/media/video/w9968cf.c
blob: 3b08bc4af909c57131ed90d67d76e496809103cb (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
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
/***************************************************************************
 * Video4Linux driver for W996[87]CF JPEG USB Dual Mode Camera Chip.       *
 *                                                                         *
 * Copyright (C) 2002-2004 by Luca Risolia <luca.risolia@studio.unibo.it>  *
 *                                                                         *
 * - Memory management code from bttv driver by Ralph Metzler,             *
 *   Marcus Metzler and Gerd Knorr.                                        *
 * - I2C interface to kernel, high-level image sensor control routines and *
 *   some symbolic names from OV511 driver by Mark W. McClelland.          *
 * - Low-level I2C fast write function by Piotr Czerczak.                  *
 * - Low-level I2C read function by Frederic Jouault.                      *
 *                                                                         *
 * This program is free software; you can redistribute it and/or modify    *
 * it under the terms of the GNU General Public License as published by    *
 * the Free Software Foundation; either version 2 of the License, or       *
 * (at your option) any later version.                                     *
 *                                                                         *
 * This program is distributed in the hope that it will be useful,         *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of          *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           *
 * GNU General Public License for more details.                            *
 *                                                                         *
 * You should have received a copy of the GNU General Public License       *
 * along with this program; if not, write to the Free Software             *
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.               *
 ***************************************************************************/

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/kmod.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/vmalloc.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/ioctl.h>
#include <linux/delay.h>
#include <linux/stddef.h>
#include <asm/page.h>
#include <asm/uaccess.h>
#include <linux/page-flags.h>
#include <linux/videodev.h>
#include <media/v4l2-ioctl.h>

#include "w9968cf.h"
#include "w9968cf_decoder.h"

static struct w9968cf_vpp_t* w9968cf_vpp;
static DECLARE_WAIT_QUEUE_HEAD(w9968cf_vppmod_wait);

static LIST_HEAD(w9968cf_dev_list); /* head of V4L registered cameras list */
static DEFINE_MUTEX(w9968cf_devlist_mutex); /* semaphore for list traversal */

static DECLARE_RWSEM(w9968cf_disconnect); /* prevent races with open() */


/****************************************************************************
 * Module macros and parameters                                             *
 ****************************************************************************/

MODULE_DEVICE_TABLE(usb, winbond_id_table);

MODULE_AUTHOR(W9968CF_MODULE_AUTHOR" "W9968CF_AUTHOR_EMAIL);
MODULE_DESCRIPTION(W9968CF_MODULE_NAME);
MODULE_VERSION(W9968CF_MODULE_VERSION);
MODULE_LICENSE(W9968CF_MODULE_LICENSE);
MODULE_SUPPORTED_DEVICE("Video");

static unsigned short simcams = W9968CF_SIMCAMS;
static short video_nr[]={[0 ... W9968CF_MAX_DEVICES-1] = -1}; /*-1=first free*/
static unsigned int packet_size[] = {[0 ... W9968CF_MAX_DEVICES-1] =
				     W9968CF_PACKET_SIZE};
static unsigned short max_buffers[] = {[0 ... W9968CF_MAX_DEVICES-1] =
				       W9968CF_BUFFERS};
static int double_buffer[] = {[0 ... W9968CF_MAX_DEVICES-1] =
			      W9968CF_DOUBLE_BUFFER};
static int clamping[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_CLAMPING};
static unsigned short filter_type[]= {[0 ... W9968CF_MAX_DEVICES-1] =
				      W9968CF_FILTER_TYPE};
static int largeview[]= {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_LARGEVIEW};
static unsigned short decompression[] = {[0 ... W9968CF_MAX_DEVICES-1] =
					 W9968CF_DECOMPRESSION};
static int upscaling[]= {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_UPSCALING};
static unsigned short force_palette[] = {[0 ... W9968CF_MAX_DEVICES-1] = 0};
static int force_rgb[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_FORCE_RGB};
static int autobright[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_AUTOBRIGHT};
static int autoexp[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_AUTOEXP};
static unsigned short lightfreq[] = {[0 ... W9968CF_MAX_DEVICES-1] =
				     W9968CF_LIGHTFREQ};
static int bandingfilter[] = {[0 ... W9968CF_MAX_DEVICES-1]=
			      W9968CF_BANDINGFILTER};
static short clockdiv[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_CLOCKDIV};
static int backlight[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_BACKLIGHT};
static int mirror[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_MIRROR};
static int monochrome[] = {[0 ... W9968CF_MAX_DEVICES-1]=W9968CF_MONOCHROME};
static unsigned int brightness[] = {[0 ... W9968CF_MAX_DEVICES-1] =
				    W9968CF_BRIGHTNESS};
static unsigned int hue[] = {[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_HUE};
static unsigned int colour[]={[0 ... W9968CF_MAX_DEVICES-1] = W9968CF_COLOUR};
static unsigned int contrast[] = {[0 ... W9968CF_MAX_DEVICES-1] =
				  W9968CF_CONTRAST};
static unsigned int whiteness[] = {[0 ... W9968CF_MAX_DEVICES-1] =
				   W9968CF_WHITENESS};
#ifdef W9968CF_DEBUG
static unsigned short debug = W9968CF_DEBUG_LEVEL;
static int specific_debug = W9968CF_SPECIFIC_DEBUG;
#endif

static unsigned int param_nv[24]; /* number of values per parameter */

module_param(simcams, ushort, 0644);
module_param_array(video_nr, short, &param_nv[0], 0444);
module_param_array(packet_size, uint, &param_nv[1], 0444);
module_param_array(max_buffers, ushort, &param_nv[2], 0444);
module_param_array(double_buffer, bool, &param_nv[3], 0444);
module_param_array(clamping, bool, &param_nv[4], 0444);
module_param_array(filter_type, ushort, &param_nv[5], 0444);
module_param_array(largeview, bool, &param_nv[6], 0444);
module_param_array(decompression, ushort, &param_nv[7], 0444);
module_param_array(upscaling, bool, &param_nv[8], 0444);
module_param_array(force_palette, ushort, &param_nv[9], 0444);
module_param_array(force_rgb, ushort, &param_nv[10], 0444);
module_param_array(autobright, bool, &param_nv[11], 0444);
module_param_array(autoexp, bool, &param_nv[12], 0444);
module_param_array(lightfreq, ushort, &param_nv[13], 0444);
module_param_array(bandingfilter, bool, &param_nv[14], 0444);
module_param_array(clockdiv, short, &param_nv[15], 0444);
module_param_array(backlight, bool, &param_nv[16], 0444);
module_param_array(mirror, bool, &param_nv[17], 0444);
module_param_array(monochrome, bool, &param_nv[18], 0444);
module_param_array(brightness, uint, &param_nv[19], 0444);
module_param_array(hue, uint, &param_nv[20], 0444);
module_param_array(colour, uint, &param_nv[21], 0444);
module_param_array(contrast, uint, &param_nv[22], 0444);
module_param_array(whiteness, uint, &param_nv[23], 0444);
#ifdef W9968CF_DEBUG
module_param(debug, ushort, 0644);
module_param(specific_debug, bool, 0644);
#endif

MODULE_PARM_DESC(simcams,
		 "\n<n> Number of cameras allowed to stream simultaneously."
		 "\nn may vary from 0 to "
		 __MODULE_STRING(W9968CF_MAX_DEVICES)"."
		 "\nDefault value is "__MODULE_STRING(W9968CF_SIMCAMS)"."
		 "\n");
MODULE_PARM_DESC(video_nr,
		 "\n<-1|n[,...]> Specify V4L minor mode number."
		 "\n -1 = use next available (default)"
		 "\n  n = use minor number n (integer >= 0)"
		 "\nYou can specify up to "__MODULE_STRING(W9968CF_MAX_DEVICES)
		 " cameras this way."
		 "\nFor example:"
		 "\nvideo_nr=-1,2,-1 would assign minor number 2 to"
		 "\nthe second camera and use auto for the first"
		 "\none and for every other camera."
		 "\n");
MODULE_PARM_DESC(packet_size,
		 "\n<n[,...]> Specify the maximum data payload"
		 "\nsize in bytes for alternate settings, for each device."
		 "\nn is scaled between 63 and 1023 "
		 "(default is "__MODULE_STRING(W9968CF_PACKET_SIZE)")."
		 "\n");
MODULE_PARM_DESC(max_buffers,
		 "\n<n[,...]> For advanced users."
		 "\nSpecify the maximum number of video frame buffers"
		 "\nto allocate for each device, from 2 to "
		 __MODULE_STRING(W9968CF_MAX_BUFFERS)
		 ". (default is "__MODULE_STRING(W9968CF_BUFFERS)")."
		 "\n");
MODULE_PARM_DESC(double_buffer,
		 "\n<0|1[,...]> "
		 "Hardware double buffering: 0 disabled, 1 enabled."
		 "\nIt should be enabled if you want smooth video output: if"
		 "\nyou obtain out of sync. video, disable it, or try to"
		 "\ndecrease the 'clockdiv' module parameter value."
		 "\nDefault value is "__MODULE_STRING(W9968CF_DOUBLE_BUFFER)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(clamping,
		 "\n<0|1[,...]> Video data clamping: 0 disabled, 1 enabled."
		 "\nDefault value is "__MODULE_STRING(W9968CF_CLAMPING)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(filter_type,
		 "\n<0|1|2[,...]> Video filter type."
		 "\n0 none, 1 (1-2-1) 3-tap filter, "
		 "2 (2-3-6-3-2) 5-tap filter."
		 "\nDefault value is "__MODULE_STRING(W9968CF_FILTER_TYPE)
		 " for every device."
		 "\nThe filter is used to reduce noise and aliasing artifacts"
		 "\nproduced by the CCD or CMOS image sensor, and the scaling"
		 " process."
		 "\n");
MODULE_PARM_DESC(largeview,
		 "\n<0|1[,...]> Large view: 0 disabled, 1 enabled."
		 "\nDefault value is "__MODULE_STRING(W9968CF_LARGEVIEW)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(upscaling,
		 "\n<0|1[,...]> Software scaling (for non-compressed video):"
		 "\n0 disabled, 1 enabled."
		 "\nDisable it if you have a slow CPU or you don't have"
		 " enough memory."
		 "\nDefault value is "__MODULE_STRING(W9968CF_UPSCALING)
		 " for every device."
		 "\nIf 'w9968cf-vpp' is not present, this parameter is"
		 " set to 0."
		 "\n");
MODULE_PARM_DESC(decompression,
		 "\n<0|1|2[,...]> Software video decompression:"
		 "\n- 0 disables decompression (doesn't allow formats needing"
		 " decompression)"
		 "\n- 1 forces decompression (allows formats needing"
		 " decompression only);"
		 "\n- 2 allows any permitted formats."
		 "\nFormats supporting compressed video are YUV422P and"
		 " YUV420P/YUV420 "
		 "\nin any resolutions where both width and height are "
		 "a multiple of 16."
		 "\nDefault value is "__MODULE_STRING(W9968CF_DECOMPRESSION)
		 " for every device."
		 "\nIf 'w9968cf-vpp' is not present, forcing decompression is "
		 "\nnot allowed; in this case this parameter is set to 2."
		 "\n");
MODULE_PARM_DESC(force_palette,
		 "\n<0"
		 "|" __MODULE_STRING(VIDEO_PALETTE_UYVY)
		 "|" __MODULE_STRING(VIDEO_PALETTE_YUV420)
		 "|" __MODULE_STRING(VIDEO_PALETTE_YUV422P)
		 "|" __MODULE_STRING(VIDEO_PALETTE_YUV420P)
		 "|" __MODULE_STRING(VIDEO_PALETTE_YUYV)
		 "|" __MODULE_STRING(VIDEO_PALETTE_YUV422)
		 "|" __MODULE_STRING(VIDEO_PALETTE_GREY)
		 "|" __MODULE_STRING(VIDEO_PALETTE_RGB555)
		 "|" __MODULE_STRING(VIDEO_PALETTE_RGB565)
		 "|" __MODULE_STRING(VIDEO_PALETTE_RGB24)
		 "|" __MODULE_STRING(VIDEO_PALETTE_RGB32)
		 "[,...]>"
		 " Force picture palette."
		 "\nIn order:"
		 "\n- 0 allows any of the following formats:"
		 "\n- UYVY    16 bpp - Original video, compression disabled"
		 "\n- YUV420  12 bpp - Original video, compression enabled"
		 "\n- YUV422P 16 bpp - Original video, compression enabled"
		 "\n- YUV420P 12 bpp - Original video, compression enabled"
		 "\n- YUVY    16 bpp - Software conversion from UYVY"
		 "\n- YUV422  16 bpp - Software conversion from UYVY"
		 "\n- GREY     8 bpp - Software conversion from UYVY"
		 "\n- RGB555  16 bpp - Software conversion from UYVY"
		 "\n- RGB565  16 bpp - Software conversion from UYVY"
		 "\n- RGB24   24 bpp - Software conversion from UYVY"
		 "\n- RGB32   32 bpp - Software conversion from UYVY"
		 "\nWhen not 0, this parameter will override 'decompression'."
		 "\nDefault value is 0 for every device."
		 "\nInitial palette is "
		 __MODULE_STRING(W9968CF_PALETTE_DECOMP_ON)"."
		 "\nIf 'w9968cf-vpp' is not present, this parameter is"
		 " set to 9 (UYVY)."
		 "\n");
MODULE_PARM_DESC(force_rgb,
		 "\n<0|1[,...]> Read RGB video data instead of BGR:"
		 "\n 1 = use RGB component ordering."
		 "\n 0 = use BGR component ordering."
		 "\nThis parameter has effect when using RGBX palettes only."
		 "\nDefault value is "__MODULE_STRING(W9968CF_FORCE_RGB)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(autobright,
		 "\n<0|1[,...]> Image sensor automatically changes brightness:"
		 "\n 0 = no, 1 = yes"
		 "\nDefault value is "__MODULE_STRING(W9968CF_AUTOBRIGHT)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(autoexp,
		 "\n<0|1[,...]> Image sensor automatically changes exposure:"
		 "\n 0 = no, 1 = yes"
		 "\nDefault value is "__MODULE_STRING(W9968CF_AUTOEXP)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(lightfreq,
		 "\n<50|60[,...]> Light frequency in Hz:"
		 "\n 50 for European and Asian lighting,"
		 " 60 for American lighting."
		 "\nDefault value is "__MODULE_STRING(W9968CF_LIGHTFREQ)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(bandingfilter,
		 "\n<0|1[,...]> Banding filter to reduce effects of"
		 " fluorescent lighting:"
		 "\n 0 disabled, 1 enabled."
		 "\nThis filter tries to reduce the pattern of horizontal"
		 "\nlight/dark bands caused by some (usually fluorescent)"
		 " lighting."
		 "\nDefault value is "__MODULE_STRING(W9968CF_BANDINGFILTER)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(clockdiv,
		 "\n<-1|n[,...]> "
		 "Force pixel clock divisor to a specific value (for experts):"
		 "\n  n may vary from 0 to 127."
		 "\n -1 for automatic value."
		 "\nSee also the 'double_buffer' module parameter."
		 "\nDefault value is "__MODULE_STRING(W9968CF_CLOCKDIV)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(backlight,
		 "\n<0|1[,...]> Objects are lit from behind:"
		 "\n 0 = no, 1 = yes"
		 "\nDefault value is "__MODULE_STRING(W9968CF_BACKLIGHT)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(mirror,
		 "\n<0|1[,...]> Reverse image horizontally:"
		 "\n 0 = no, 1 = yes"
		 "\nDefault value is "__MODULE_STRING(W9968CF_MIRROR)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(monochrome,
		 "\n<0|1[,...]> Use image sensor as monochrome sensor:"
		 "\n 0 = no, 1 = yes"
		 "\nNot all the sensors support monochrome color."
		 "\nDefault value is "__MODULE_STRING(W9968CF_MONOCHROME)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(brightness,
		 "\n<n[,...]> Set picture brightness (0-65535)."
		 "\nDefault value is "__MODULE_STRING(W9968CF_BRIGHTNESS)
		 " for every device."
		 "\nThis parameter has no effect if 'autobright' is enabled."
		 "\n");
MODULE_PARM_DESC(hue,
		 "\n<n[,...]> Set picture hue (0-65535)."
		 "\nDefault value is "__MODULE_STRING(W9968CF_HUE)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(colour,
		 "\n<n[,...]> Set picture saturation (0-65535)."
		 "\nDefault value is "__MODULE_STRING(W9968CF_COLOUR)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(contrast,
		 "\n<n[,...]> Set picture contrast (0-65535)."
		 "\nDefault value is "__MODULE_STRING(W9968CF_CONTRAST)
		 " for every device."
		 "\n");
MODULE_PARM_DESC(whiteness,
		 "\n<n[,...]> Set picture whiteness (0-65535)."
		 "\nDefault value is "__MODULE_STRING(W9968CF_WHITENESS)
		 " for every device."
		 "\n");
#ifdef W9968CF_DEBUG
MODULE_PARM_DESC(debug,
		 "\n<n> Debugging information level, from 0 to 6:"
		 "\n0 = none (use carefully)"
		 "\n1 = critical errors"
		 "\n2 = significant informations"
		 "\n3 = configuration or general messages"
		 "\n4 = warnings"
		 "\n5 = called functions"
		 "\n6 = function internals"
		 "\nLevel 5 and 6 are useful for testing only, when only "
		 "one device is used."
		 "\nDefault value is "__MODULE_STRING(W9968CF_DEBUG_LEVEL)"."
		 "\n");
MODULE_PARM_DESC(specific_debug,
		 "\n<0|1> Enable or disable specific debugging messages:"
		 "\n0 = print messages concerning every level"
		 " <= 'debug' level."
		 "\n1 = print messages concerning the level"
		 " indicated by 'debug'."
		 "\nDefault value is "
		 __MODULE_STRING(W9968CF_SPECIFIC_DEBUG)"."
		 "\n");
#endif /* W9968CF_DEBUG */



/****************************************************************************
 * Some prototypes                                                          *
 ****************************************************************************/

/* Video4linux interface */
static const struct v4l2_file_operations w9968cf_fops;
static int w9968cf_open(struct file *);
static int w9968cf_release(struct file *);
static int w9968cf_mmap(struct file *, struct vm_area_struct *);
static long w9968cf_ioctl(struct file *, unsigned, unsigned long);
static ssize_t w9968cf_read(struct file *, char __user *, size_t, loff_t *);
static long w9968cf_v4l_ioctl(struct file *, unsigned int,
			     void __user *);

/* USB-specific */
static int w9968cf_start_transfer(struct w9968cf_device*);
static int w9968cf_stop_transfer(struct w9968cf_device*);
static int w9968cf_write_reg(struct w9968cf_device*, u16 value, u16 index);
static int w9968cf_read_reg(struct w9968cf_device*, u16 index);
static int w9968cf_write_fsb(struct w9968cf_device*, u16* data);
static int w9968cf_write_sb(struct w9968cf_device*, u16 value);
static int w9968cf_read_sb(struct w9968cf_device*);
static int w9968cf_upload_quantizationtables(struct w9968cf_device*);
static void w9968cf_urb_complete(struct urb *urb);

/* Low-level I2C (SMBus) I/O */
static int w9968cf_smbus_start(struct w9968cf_device*);
static int w9968cf_smbus_stop(struct w9968cf_device*);
static int w9968cf_smbus_write_byte(struct w9968cf_device*, u8 v);
static int w9968cf_smbus_read_byte(struct w9968cf_device*, u8* v);
static int w9968cf_smbus_write_ack(struct w9968cf_device*);
static int w9968cf_smbus_read_ack(struct w9968cf_device*);
static int w9968cf_smbus_refresh_bus(struct w9968cf_device*);
static int w9968cf_i2c_adap_read_byte(struct w9968cf_device* cam,
				      u16 address, u8* value);
static int w9968cf_i2c_adap_read_byte_data(struct w9968cf_device*, u16 address,
					   u8 subaddress, u8* value);
static int w9968cf_i2c_adap_write_byte(struct w9968cf_device*,
				       u16 address, u8 subaddress);
static int w9968cf_i2c_adap_fastwrite_byte_data(struct w9968cf_device*,
						u16 address, u8 subaddress,
						u8 value);

/* I2C interface to kernel */
static int w9968cf_i2c_init(struct w9968cf_device*);
static int w9968cf_i2c_smbus_xfer(struct i2c_adapter*, u16 addr,
				  unsigned short flags, char read_write,
				  u8 command, int size, union i2c_smbus_data*);
static u32 w9968cf_i2c_func(struct i2c_adapter*);

/* Memory management */
static void* rvmalloc(unsigned long size);
static void rvfree(void *mem, unsigned long size);
static void w9968cf_deallocate_memory(struct w9968cf_device*);
static int  w9968cf_allocate_memory(struct w9968cf_device*);

/* High-level image sensor control functions */
static int w9968cf_sensor_set_control(struct w9968cf_device*,int cid,int val);
static int w9968cf_sensor_get_control(struct w9968cf_device*,int cid,int *val);
static int w9968cf_sensor_cmd(struct w9968cf_device*,
			      unsigned int cmd, void *arg);
static int w9968cf_sensor_init(struct w9968cf_device*);
static int w9968cf_sensor_update_settings(struct w9968cf_device*);
static int w9968cf_sensor_get_picture(struct w9968cf_device*);
static int w9968cf_sensor_update_picture(struct w9968cf_device*,
					 struct video_picture pict);

/* Other helper functions */
static void w9968cf_configure_camera(struct w9968cf_device*,struct usb_device*,
				     enum w9968cf_model_id,
				     const unsigned short dev_nr);
static void w9968cf_adjust_configuration(struct w9968cf_device*);
static int w9968cf_turn_on_led(struct w9968cf_device*);
static int w9968cf_init_chip(struct w9968cf_device*);
static inline u16 w9968cf_valid_palette(u16 palette);
static inline u16 w9968cf_valid_depth(u16 palette);
static inline u8 w9968cf_need_decompression(u16 palette);
static int w9968cf_set_picture(struct w9968cf_device*, struct video_picture);
static int w9968cf_set_window(struct w9968cf_device*, struct video_window);
static int w9968cf_postprocess_frame(struct w9968cf_device*,
				     struct w9968cf_frame_t*);
static int w9968cf_adjust_window_size(struct w9968cf_device*, u16* w, u16* h);
static void w9968cf_init_framelist(struct w9968cf_device*);
static void w9968cf_push_frame(struct w9968cf_device*, u8 f_num);
static void w9968cf_pop_frame(struct w9968cf_device*,struct w9968cf_frame_t**);
static void w9968cf_release_resources(struct w9968cf_device*);



/****************************************************************************
 * Symbolic names                                                           *
 ****************************************************************************/

/* Used to represent a list of values and their respective symbolic names */
struct w9968cf_symbolic_list {
	const int num;
	const char *name;
};

/*--------------------------------------------------------------------------
  Returns the name of the matching element in the symbolic_list array. The
  end of the list must be marked with an element that has a NULL name.
  --------------------------------------------------------------------------*/
static inline const char *
symbolic(struct w9968cf_symbolic_list list[], const int num)
{
	int i;

	for (i = 0; list[i].name != NULL; i++)
		if (list[i].num == num)
			return (list[i].name);

	return "Unknown";
}

static struct w9968cf_symbolic_list camlist[] = {
	{ W9968CF_MOD_GENERIC, "W996[87]CF JPEG USB Dual Mode Camera" },
	{ W9968CF_MOD_CLVBWGP, "Creative Labs Video Blaster WebCam Go Plus" },

	/* Other cameras (having the same descriptors as Generic W996[87]CF) */
	{ W9968CF_MOD_ADPVDMA, "Aroma Digi Pen VGA Dual Mode ADG-5000" },
	{ W9986CF_MOD_AAU, "AVerMedia AVerTV USB" },
	{ W9968CF_MOD_CLVBWG, "Creative Labs Video Blaster WebCam Go" },
	{ W9968CF_MOD_LL, "Lebon LDC-035A" },
	{ W9968CF_MOD_EEEMC, "Ezonics EZ-802 EZMega Cam" },
	{ W9968CF_MOD_OOE, "OmniVision OV8610-EDE" },
	{ W9968CF_MOD_ODPVDMPC, "OPCOM Digi Pen VGA Dual Mode Pen Camera" },
	{ W9968CF_MOD_PDPII, "Pretec Digi Pen-II" },
	{ W9968CF_MOD_PDP480, "Pretec DigiPen-480" },

	{  -1, NULL }
};

static struct w9968cf_symbolic_list senlist[] = {
	{ CC_OV76BE,   "OV76BE" },
	{ CC_OV7610,   "OV7610" },
	{ CC_OV7620,   "OV7620" },
	{ CC_OV7620AE, "OV7620AE" },
	{ CC_OV6620,   "OV6620" },
	{ CC_OV6630,   "OV6630" },
	{ CC_OV6630AE, "OV6630AE" },
	{ CC_OV6630AF, "OV6630AF" },
	{ -1, NULL }
};

/* Video4Linux1 palettes */
static struct w9968cf_symbolic_list v4l1_plist[] = {
	{ VIDEO_PALETTE_GREY,    "GREY" },
	{ VIDEO_PALETTE_HI240,   "HI240" },
	{ VIDEO_PALETTE_RGB565,  "RGB565" },
	{ VIDEO_PALETTE_RGB24,   "RGB24" },
	{ VIDEO_PALETTE_RGB32,   "RGB32" },
	{ VIDEO_PALETTE_RGB555,  "RGB555" },
	{ VIDEO_PALETTE_YUV422,  "YUV422" },
	{ VIDEO_PALETTE_YUYV,    "YUYV" },
	{ VIDEO_PALETTE_UYVY,    "UYVY" },
	{ VIDEO_PALETTE_YUV420,  "YUV420" },
	{ VIDEO_PALETTE_YUV411,  "YUV411" },
	{ VIDEO_PALETTE_RAW,     "RAW" },
	{ VIDEO_PALETTE_YUV422P, "YUV422P" },
	{ VIDEO_PALETTE_YUV411P, "YUV411P" },
	{ VIDEO_PALETTE_YUV420P, "YUV420P" },
	{ VIDEO_PALETTE_YUV410P, "YUV410P" },
	{ -1, NULL }
};

/* Decoder error codes: */
static struct w9968cf_symbolic_list decoder_errlist[] = {
	{ W9968CF_DEC_ERR_CORRUPTED_DATA, "Corrupted data" },
	{ W9968CF_DEC_ERR_BUF_OVERFLOW,   "Buffer overflow" },
	{ W9968CF_DEC_ERR_NO_SOI,         "SOI marker not found" },
	{ W9968CF_DEC_ERR_NO_SOF0,        "SOF0 marker not found" },
	{ W9968CF_DEC_ERR_NO_SOS,         "SOS marker not found" },
	{ W9968CF_DEC_ERR_NO_EOI,         "EOI marker not found" },
	{ -1, NULL }
};

/* URB error codes: */
static struct w9968cf_symbolic_list urb_errlist[] = {
	{ -ENOMEM,    "No memory for allocation of internal structures" },
	{ -ENOSPC,    "The host controller's bandwidth is already consumed" },
	{ -ENOENT,    "URB was canceled by unlink_urb" },
	{ -EXDEV,     "ISO transfer only partially completed" },
	{ -EAGAIN,    "Too match scheduled for the future" },
	{ -ENXIO,     "URB already queued" },
	{ -EFBIG,     "Too much ISO frames requested" },
	{ -ENOSR,     "Buffer error (overrun)" },
	{ -EPIPE,     "Specified endpoint is stalled (device not responding)"},
	{ -EOVERFLOW, "Babble (too much data)" },
	{ -EPROTO,    "Bit-stuff error (bad cable?)" },
	{ -EILSEQ,    "CRC/Timeout" },
	{ -ETIME,     "Device does not respond to token" },
	{ -ETIMEDOUT, "Device does not respond to command" },
	{ -1, NULL }
};

/****************************************************************************
 * Memory management functions                                              *
 ****************************************************************************/
static void* rvmalloc(unsigned long size)
{
	void* mem;
	unsigned long adr;

	size = PAGE_ALIGN(size);
	mem = vmalloc_32(size);
	if (!mem)
		return NULL;

	memset(mem, 0, size); /* Clear the ram out, no junk to the user */
	adr = (unsigned long) mem;
	while (size > 0) {
		SetPageReserved(vmalloc_to_page((void *)adr));
		adr += PAGE_SIZE;
		size -= PAGE_SIZE;
	}

	return mem;
}


static void rvfree(void* mem, unsigned long size)
{
	unsigned long adr;

	if (!mem)
		return;

	adr = (unsigned long) mem;
	while ((long) size > 0) {
		ClearPageReserved(vmalloc_to_page((void *)adr));
		adr += PAGE_SIZE;
		size -= PAGE_SIZE;
	}
	vfree(mem);
}


/*--------------------------------------------------------------------------
  Deallocate previously allocated memory.
  --------------------------------------------------------------------------*/
static void w9968cf_deallocate_memory(struct w9968cf_device* cam)
{
	u8 i;

	/* Free the isochronous transfer buffers */
	for (i = 0; i < W9968CF_URBS; i++) {
		kfree(cam->transfer_buffer[i]);
		cam->transfer_buffer[i] = NULL;
	}

	/* Free temporary frame buffer */
	if (cam->frame_tmp.buffer) {
		rvfree(cam->frame_tmp.buffer, cam->frame_tmp.size);
		cam->frame_tmp.buffer = NULL;
	}

	/* Free helper buffer */
	if (cam->frame_vpp.buffer) {
		rvfree(cam->frame_vpp.buffer, cam->frame_vpp.size);
		cam->frame_vpp.buffer = NULL;
	}

	/* Free video frame buffers */
	if (cam->frame[0].buffer) {
		rvfree(cam->frame[0].buffer, cam->nbuffers*cam->frame[0].size);
		cam->frame[0].buffer = NULL;
	}

	cam->nbuffers = 0;

	DBG(5, "Memory successfully deallocated")
}


/*--------------------------------------------------------------------------
  Allocate memory buffers for USB transfers and video frames.
  This function is called by open() only.
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_allocate_memory(struct w9968cf_device* cam)
{
	const u16 p_size = wMaxPacketSize[cam->altsetting-1];
	void* buff = NULL;
	unsigned long hw_bufsize, vpp_bufsize;
	u8 i, bpp;

	/* NOTE: Deallocation is done elsewhere in case of error */

	/* Calculate the max amount of raw data per frame from the device */
	hw_bufsize = cam->maxwidth*cam->maxheight*2;

	/* Calculate the max buf. size needed for post-processing routines */
	bpp = (w9968cf_vpp) ? 4 : 2;
	if (cam->upscaling)
		vpp_bufsize = max(W9968CF_MAX_WIDTH*W9968CF_MAX_HEIGHT*bpp,
				  cam->maxwidth*cam->maxheight*bpp);
	else
		vpp_bufsize = cam->maxwidth*cam->maxheight*bpp;

	/* Allocate memory for the isochronous transfer buffers */
	for (i = 0; i < W9968CF_URBS; i++) {
		if (!(cam->transfer_buffer[i] =
		      kzalloc(W9968CF_ISO_PACKETS*p_size, GFP_KERNEL))) {
			DBG(1, "Couldn't allocate memory for the isochronous "
			       "transfer buffers (%u bytes)",
			    p_size * W9968CF_ISO_PACKETS)
			return -ENOMEM;
		}
	}

	/* Allocate memory for the temporary frame buffer */
	if (!(cam->frame_tmp.buffer = rvmalloc(hw_bufsize))) {
		DBG(1, "Couldn't allocate memory for the temporary "
		       "video frame buffer (%lu bytes)", hw_bufsize)
		return -ENOMEM;
	}
	cam->frame_tmp.size = hw_bufsize;
	cam->frame_tmp.number = -1;

	/* Allocate memory for the helper buffer */
	if (w9968cf_vpp) {
		if (!(cam->frame_vpp.buffer = rvmalloc(vpp_bufsize))) {
			DBG(1, "Couldn't allocate memory for the helper buffer"
			       " (%lu bytes)", vpp_bufsize)
			return -ENOMEM;
		}
		cam->frame_vpp.size = vpp_bufsize;
	} else
		cam->frame_vpp.buffer = NULL;

	/* Allocate memory for video frame buffers */
	cam->nbuffers = cam->max_buffers;
	while (cam->nbuffers >= 2) {
		if ((buff = rvmalloc(cam->nbuffers * vpp_bufsize)))
			break;
		else
			cam->nbuffers--;
	}

	if (!buff) {
		DBG(1, "Couldn't allocate memory for the video frame buffers")
		cam->nbuffers = 0;
		return -ENOMEM;
	}

	if (cam->nbuffers != cam->max_buffers)
		DBG(2, "Couldn't allocate memory for %u video frame buffers. "
		       "Only memory for %u buffers has been allocated",
		    cam->max_buffers, cam->nbuffers)

	for (i = 0; i < cam->nbuffers; i++) {
		cam->frame[i].buffer = buff + i*vpp_bufsize;
		cam->frame[i].size = vpp_bufsize;
		cam->frame[i].number = i;
		/* Circular list */
		if (i != cam->nbuffers-1)
			cam->frame[i].next = &cam->frame[i+1];
		else
			cam->frame[i].next = &cam->frame[0];
		cam->frame[i].status = F_UNUSED;
	}

	DBG(5, "Memory successfully allocated")
	return 0;
}



/****************************************************************************
 * USB-specific functions                                                   *
 ****************************************************************************/

/*--------------------------------------------------------------------------
  This is an handler function which is called after the URBs are completed.
  It collects multiple data packets coming from the camera by putting them
  into frame buffers: one or more zero data length data packets are used to
  mark the end of a video frame; the first non-zero data packet is the start
  of the next video frame; if an error is encountered in a packet, the entire
  video frame is discarded and grabbed again.
  If there are no requested frames in the FIFO list, packets are collected into
  a temporary buffer.
  --------------------------------------------------------------------------*/
static void w9968cf_urb_complete(struct urb *urb)
{
	struct w9968cf_device* cam = (struct w9968cf_device*)urb->context;
	struct w9968cf_frame_t** f;
	unsigned int len, status;
	void* pos;
	u8 i;
	int err = 0;

	if ((!cam->streaming) || cam->disconnected) {
		DBG(4, "Got interrupt, but not streaming")
		return;
	}

	/* "(*f)" will be used instead of "cam->frame_current" */
	f = &cam->frame_current;

	/* If a frame has been requested and we are grabbing into
	   the temporary frame, we'll switch to that requested frame */
	if ((*f) == &cam->frame_tmp && *cam->requested_frame) {
		if (cam->frame_tmp.status == F_GRABBING) {
			w9968cf_pop_frame(cam, &cam->frame_current);
			(*f)->status = F_GRABBING;
			(*f)->length = cam->frame_tmp.length;
			memcpy((*f)->buffer, cam->frame_tmp.buffer,
			       (*f)->length);
			DBG(6, "Switched from temp. frame to frame #%d",
			    (*f)->number)
		}
	}

	for (i = 0; i < urb->number_of_packets; i++) {
		len = urb->iso_frame_desc[i].actual_length;
		status = urb->iso_frame_desc[i].status;
		pos = urb->iso_frame_desc[i].offset + urb->transfer_buffer;

		if (status && len != 0) {
			DBG(4, "URB failed, error in data packet "
			       "(error #%u, %s)",
			    status, symbolic(urb_errlist, status))
			(*f)->status = F_ERROR;
			continue;
		}

		if (len) { /* start of frame */

			if ((*f)->status == F_UNUSED) {
				(*f)->status = F_GRABBING;
				(*f)->length = 0;
			}

			/* Buffer overflows shouldn't happen, however...*/
			if ((*f)->length + len > (*f)->size) {
				DBG(4, "Buffer overflow: bad data packets")
				(*f)->status = F_ERROR;
			}

			if ((*f)->status == F_GRABBING) {
				memcpy((*f)->buffer + (*f)->length, pos, len);
				(*f)->length += len;
			}

		} else if ((*f)->status == F_GRABBING) { /* end of frame */

			DBG(6, "Frame #%d successfully grabbed", (*f)->number)

			if (cam->vpp_flag & VPP_DECOMPRESSION) {
				err = w9968cf_vpp->check_headers((*f)->buffer,
								 (*f)->length);
				if (err) {
					DBG(4, "Skip corrupted frame: %s",
					    symbolic(decoder_errlist, err))
					(*f)->status = F_UNUSED;
					continue; /* grab this frame again */
				}
			}

			(*f)->status = F_READY;
			(*f)->queued = 0;

			/* Take a pointer to the new frame from the FIFO list.
			   If the list is empty,we'll use the temporary frame*/
			if (*cam->requested_frame)
				w9968cf_pop_frame(cam, &cam->frame_current);
			else {
				cam->frame_current = &cam->frame_tmp;
				(*f)->status = F_UNUSED;
			}

		} else if ((*f)->status == F_ERROR)
			(*f)->status = F_UNUSED; /* grab it again */

		PDBGG("Frame length %lu | pack.#%u | pack.len. %u | state %d",
		      (unsigned long)(*f)->length, i, len, (*f)->status)

	} /* end for */

	/* Resubmit this URB */
	urb->dev = cam->usbdev;
	urb->status = 0;
	spin_lock(&cam->urb_lock);
	if (cam->streaming)
		if ((err = usb_submit_urb(urb, GFP_ATOMIC))) {
			cam->misconfigured = 1;
			DBG(1, "Couldn't resubmit the URB: error %d, %s",
			    err, symbolic(urb_errlist, err))
		}
	spin_unlock(&cam->urb_lock);

	/* Wake up the user process */
	wake_up_interruptible(&cam->wait_queue);
}


/*---------------------------------------------------------------------------
  Setup the URB structures for the isochronous transfer.
  Submit the URBs so that the data transfer begins.
  Return 0 on success, a negative number otherwise.
  ---------------------------------------------------------------------------*/
static int w9968cf_start_transfer(struct w9968cf_device* cam)
{
	struct usb_device *udev = cam->usbdev;
	struct urb* urb;
	const u16 p_size = wMaxPacketSize[cam->altsetting-1];
	u16 w, h, d;
	int vidcapt;
	u32 t_size;
	int err = 0;
	s8 i, j;

	for (i = 0; i < W9968CF_URBS; i++) {
		urb = usb_alloc_urb(W9968CF_ISO_PACKETS, GFP_KERNEL);
		if (!urb) {
			for (j = 0; j < i; j++)
				usb_free_urb(cam->urb[j]);
			DBG(1, "Couldn't allocate the URB structures")
			return -ENOMEM;
		}

		cam->urb[i] = urb;
		urb->dev = udev;
		urb->context = (void*)cam;
		urb->pipe = usb_rcvisocpipe(udev, 1);
		urb->transfer_flags = URB_ISO_ASAP;
		urb->number_of_packets = W9968CF_ISO_PACKETS;
		urb->complete = w9968cf_urb_complete;
		urb->transfer_buffer = cam->transfer_buffer[i];
		urb->transfer_buffer_length = p_size*W9968CF_ISO_PACKETS;
		urb->interval = 1;
		for (j = 0; j < W9968CF_ISO_PACKETS; j++) {
			urb->iso_frame_desc[j].offset = p_size*j;
			urb->iso_frame_desc[j].length = p_size;
		}
	}

	/* Transfer size per frame, in WORD ! */
	d = cam->hw_depth;
	w = cam->hw_width;
	h = cam->hw_height;

	t_size = (w*h*d)/16;

	err = w9968cf_write_reg(cam, 0xbf17, 0x00); /* reset everything */
	err += w9968cf_write_reg(cam, 0xbf10, 0x00); /* normal operation */

	/* Transfer size */
	err += w9968cf_write_reg(cam, t_size & 0xffff, 0x3d); /* low bits */
	err += w9968cf_write_reg(cam, t_size >> 16, 0x3e);    /* high bits */

	if (cam->vpp_flag & VPP_DECOMPRESSION)
		err += w9968cf_upload_quantizationtables(cam);

	vidcapt = w9968cf_read_reg(cam, 0x16); /* read picture settings */
	err += w9968cf_write_reg(cam, vidcapt|0x8000, 0x16); /* capt. enable */

	err += usb_set_interface(udev, 0, cam->altsetting);
	err += w9968cf_write_reg(cam, 0x8a05, 0x3c); /* USB FIFO enable */

	if (err || (vidcapt < 0)) {
		for (i = 0; i < W9968CF_URBS; i++)
			usb_free_urb(cam->urb[i]);
		DBG(1, "Couldn't tell the camera to start the data transfer")
		return err;
	}

	w9968cf_init_framelist(cam);

	/* Begin to grab into the temporary buffer */
	cam->frame_tmp.status = F_UNUSED;
	cam->frame_tmp.queued = 0;
	cam->frame_current = &cam->frame_tmp;

	if (!(cam->vpp_flag & VPP_DECOMPRESSION))
		DBG(5, "Isochronous transfer size: %lu bytes/frame",
		    (unsigned long)t_size*2)

	DBG(5, "Starting the isochronous transfer...")

	cam->streaming = 1;

	/* Submit the URBs */
	for (i = 0; i < W9968CF_URBS; i++) {
		err = usb_submit_urb(cam->urb[i], GFP_KERNEL);
		if (err) {
			cam->streaming = 0;
			for (j = i-1; j >= 0; j--) {
				usb_kill_urb(cam->urb[j]);
				usb_free_urb(cam->urb[j]);
			}
			DBG(1, "Couldn't send a transfer request to the "
			       "USB core (error #%d, %s)", err,
			    symbolic(urb_errlist, err))
			return err;
		}
	}

	return 0;
}


/*--------------------------------------------------------------------------
  Stop the isochronous transfer and set alternate setting to 0 (0Mb/s).
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_stop_transfer(struct w9968cf_device* cam)
{
	struct usb_device *udev = cam->usbdev;
	unsigned long lock_flags;
	int err = 0;
	s8 i;

	if (!cam->streaming)
		return 0;

	/* This avoids race conditions with usb_submit_urb()
	   in the URB completition handler */
	spin_lock_irqsave(&cam->urb_lock, lock_flags);
	cam->streaming = 0;
	spin_unlock_irqrestore(&cam->urb_lock, lock_flags);

	for (i = W9968CF_URBS-1; i >= 0; i--)
		if (cam->urb[i]) {
			usb_kill_urb(cam->urb[i]);
			usb_free_urb(cam->urb[i]);
			cam->urb[i] = NULL;
		}

	if (cam->disconnected)
		goto exit;

	err = w9968cf_write_reg(cam, 0x0a05, 0x3c); /* stop USB transfer */
	err += usb_set_interface(udev, 0, 0); /* 0 Mb/s */
	err += w9968cf_write_reg(cam, 0x0000, 0x39); /* disable JPEG encoder */
	err += w9968cf_write_reg(cam, 0x0000, 0x16); /* stop video capture */

	if (err) {
		DBG(2, "Failed to tell the camera to stop the isochronous "
		       "transfer. However this is not a critical error.")
		return -EIO;
	}

exit:
	DBG(5, "Isochronous transfer stopped")
	return 0;
}


/*--------------------------------------------------------------------------
  Write a W9968CF register.
  Return 0 on success, -1 otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_write_reg(struct w9968cf_device* cam, u16 value, u16 index)
{
	struct usb_device* udev = cam->usbdev;
	int res;

	res = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 0,
			      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
			      value, index, NULL, 0, W9968CF_USB_CTRL_TIMEOUT);

	if (res < 0)
		DBG(4, "Failed to write a register "
		       "(value 0x%04X, index 0x%02X, error #%d, %s)",
		    value, index, res, symbolic(urb_errlist, res))

	return (res >= 0) ? 0 : -1;
}


/*--------------------------------------------------------------------------
  Read a W9968CF register.
  Return the register value on success, -1 otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_read_reg(struct w9968cf_device* cam, u16 index)
{
	struct usb_device* udev = cam->usbdev;
	u16* buff = cam->control_buffer;
	int res;

	res = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), 1,
			      USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
			      0, index, buff, 2, W9968CF_USB_CTRL_TIMEOUT);

	if (res < 0)
		DBG(4, "Failed to read a register "
		       "(index 0x%02X, error #%d, %s)",
		    index, res, symbolic(urb_errlist, res))

	return (res >= 0) ? (int)(*buff) : -1;
}


/*--------------------------------------------------------------------------
  Write 64-bit data to the fast serial bus registers.
  Return 0 on success, -1 otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_write_fsb(struct w9968cf_device* cam, u16* data)
{
	struct usb_device* udev = cam->usbdev;
	u16 value;
	int res;

	value = *data++;

	res = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 0,
			      USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE,
			      value, 0x06, data, 6, W9968CF_USB_CTRL_TIMEOUT);

	if (res < 0)
		DBG(4, "Failed to write the FSB registers "
		       "(error #%d, %s)", res, symbolic(urb_errlist, res))

	return (res >= 0) ? 0 : -1;
}


/*--------------------------------------------------------------------------
  Write data to the serial bus control register.
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_write_sb(struct w9968cf_device* cam, u16 value)
{
	int err = 0;

	err = w9968cf_write_reg(cam, value, 0x01);
	udelay(W9968CF_I2C_BUS_DELAY);

	return err;
}


/*--------------------------------------------------------------------------
  Read data from the serial bus control register.
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_read_sb(struct w9968cf_device* cam)
{
	int v = 0;

	v = w9968cf_read_reg(cam, 0x01);
	udelay(W9968CF_I2C_BUS_DELAY);

	return v;
}


/*--------------------------------------------------------------------------
  Upload quantization tables for the JPEG compression.
  This function is called by w9968cf_start_transfer().
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_upload_quantizationtables(struct w9968cf_device* cam)
{
	u16 a, b;
	int err = 0, i, j;

	err += w9968cf_write_reg(cam, 0x0010, 0x39); /* JPEG clock enable */

	for (i = 0, j = 0; i < 32; i++, j += 2) {
		a = Y_QUANTABLE[j] | ((unsigned)(Y_QUANTABLE[j+1]) << 8);
		b = UV_QUANTABLE[j] | ((unsigned)(UV_QUANTABLE[j+1]) << 8);
		err += w9968cf_write_reg(cam, a, 0x40+i);
		err += w9968cf_write_reg(cam, b, 0x60+i);
	}
	err += w9968cf_write_reg(cam, 0x0012, 0x39); /* JPEG encoder enable */

	return err;
}



/****************************************************************************
 * Low-level I2C I/O functions.                                             *
 * The adapter supports the following I2C transfer functions:               *
 * i2c_adap_fastwrite_byte_data() (at 400 kHz bit frequency only)           *
 * i2c_adap_read_byte_data()                                                *
 * i2c_adap_read_byte()                                                     *
 ****************************************************************************/

static int w9968cf_smbus_start(struct w9968cf_device* cam)
{
	int err = 0;

	err += w9968cf_write_sb(cam, 0x0011); /* SDE=1, SDA=0, SCL=1 */
	err += w9968cf_write_sb(cam, 0x0010); /* SDE=1, SDA=0, SCL=0 */

	return err;
}


static int w9968cf_smbus_stop(struct w9968cf_device* cam)
{
	int err = 0;

	err += w9968cf_write_sb(cam, 0x0011); /* SDE=1, SDA=0, SCL=1 */
	err += w9968cf_write_sb(cam, 0x0013); /* SDE=1, SDA=1, SCL=1 */

	return err;
}


static int w9968cf_smbus_write_byte(struct w9968cf_device* cam, u8 v)
{
	u8 bit;
	int err = 0, sda;

	for (bit = 0 ; bit < 8 ; bit++) {
		sda = (v & 0x80) ? 2 : 0;
		v <<= 1;
		/* SDE=1, SDA=sda, SCL=0 */
		err += w9968cf_write_sb(cam, 0x10 | sda);
		/* SDE=1, SDA=sda, SCL=1 */
		err += w9968cf_write_sb(cam, 0x11 | sda);
		/* SDE=1, SDA=sda, SCL=0 */
		err += w9968cf_write_sb(cam, 0x10 | sda);
	}

	return err;
}


static int w9968cf_smbus_read_byte(struct w9968cf_device* cam, u8* v)
{
	u8 bit;
	int err = 0;

	*v = 0;
	for (bit = 0 ; bit < 8 ; bit++) {
		*v <<= 1;
		err += w9968cf_write_sb(cam, 0x0013);
		*v |= (w9968cf_read_sb(cam) & 0x0008) ? 1 : 0;
		err += w9968cf_write_sb(cam, 0x0012);
	}

	return err;
}


static int w9968cf_smbus_write_ack(struct w9968cf_device* cam)
{
	int err = 0;

	err += w9968cf_write_sb(cam, 0x0010); /* SDE=1, SDA=0, SCL=0 */
	err += w9968cf_write_sb(cam, 0x0011); /* SDE=1, SDA=0, SCL=1 */
	err += w9968cf_write_sb(cam, 0x0010); /* SDE=1, SDA=0, SCL=0 */

	return err;
}


static int w9968cf_smbus_read_ack(struct w9968cf_device* cam)
{
	int err = 0, sda;

	err += w9968cf_write_sb(cam, 0x0013); /* SDE=1, SDA=1, SCL=1 */
	sda = (w9968cf_read_sb(cam) & 0x08) ? 1 : 0; /* sda = SDA */
	err += w9968cf_write_sb(cam, 0x0012); /* SDE=1, SDA=1, SCL=0 */
	if (sda < 0)
		err += sda;
	if (sda == 1) {
		DBG(6, "Couldn't receive the ACK")
		err += -1;
	}

	return err;
}


/* This seems to refresh the communication through the serial bus */
static int w9968cf_smbus_refresh_bus(struct w9968cf_device* cam)
{
	int err = 0, j;

	for (j = 1; j <= 10; j++) {
		err = w9968cf_write_reg(cam, 0x0020, 0x01);
		err += w9968cf_write_reg(cam, 0x0000, 0x01);
		if (err)
			break;
	}

	return err;
}


/* SMBus protocol: S Addr Wr [A] Subaddr [A] Value [A] P */
static int
w9968cf_i2c_adap_fastwrite_byte_data(struct w9968cf_device* cam,
				     u16 address, u8 subaddress,u8 value)
{
	u16* data = cam->data_buffer;
	int err = 0;

	err += w9968cf_smbus_refresh_bus(cam);

	/* Enable SBUS outputs */
	err += w9968cf_write_sb(cam, 0x0020);

	data[0] = 0x082f | ((address & 0x80) ? 0x1500 : 0x0);
	data[0] |= (address & 0x40) ? 0x4000 : 0x0;
	data[1] = 0x2082 | ((address & 0x40) ? 0x0005 : 0x0);
	data[1] |= (address & 0x20) ? 0x0150 : 0x0;
	data[1] |= (address & 0x10) ? 0x5400 : 0x0;
	data[2] = 0x8208 | ((address & 0x08) ? 0x0015 : 0x0);
	data[2] |= (address & 0x04) ? 0x0540 : 0x0;
	data[2] |= (address & 0x02) ? 0x5000 : 0x0;
	data[3] = 0x1d20 | ((address & 0x02) ? 0x0001 : 0x0);
	data[3] |= (address & 0x01) ? 0x0054 : 0x0;

	err += w9968cf_write_fsb(cam, data);

	data[0] = 0x8208 | ((subaddress & 0x80) ? 0x0015 : 0x0);
	data[0] |= (subaddress & 0x40) ? 0x0540 : 0x0;
	data[0] |= (subaddress & 0x20) ? 0x5000 : 0x0;
	data[1] = 0x0820 | ((subaddress & 0x20) ? 0x0001 : 0x0);
	data[1] |= (subaddress & 0x10) ? 0x0054 : 0x0;
	data[1] |= (subaddress & 0x08) ? 0x1500 : 0x0;
	data[1] |= (subaddress & 0x04) ? 0x4000 : 0x0;
	data[2] = 0x2082 | ((subaddress & 0x04) ? 0x0005 : 0x0);
	data[2] |= (subaddress & 0x02) ? 0x0150 : 0x0;
	data[2] |= (subaddress & 0x01) ? 0x5400 : 0x0;
	data[3] = 0x001d;

	err += w9968cf_write_fsb(cam, data);

	data[0] = 0x8208 | ((value & 0x80) ? 0x0015 : 0x0);
	data[0] |= (value & 0x40) ? 0x0540 : 0x0;
	data[0] |= (value & 0x20) ? 0x5000 : 0x0;
	data[1] = 0x0820 | ((value & 0x20) ? 0x0001 : 0x0);
	data[1] |= (value & 0x10) ? 0x0054 : 0x0;
	data[1] |= (value & 0x08) ? 0x1500 : 0x0;
	data[1] |= (value & 0x04) ? 0x4000 : 0x0;
	data[2] = 0x2082 | ((value & 0x04) ? 0x0005 : 0x0);
	data[2] |= (value & 0x02) ? 0x0150 : 0x0;
	data[2] |= (value & 0x01) ? 0x5400 : 0x0;
	data[3] = 0xfe1d;

	err += w9968cf_write_fsb(cam, data);

	/* Disable SBUS outputs */
	err += w9968cf_write_sb(cam, 0x0000);

	if (!err)
		DBG(5, "I2C write byte data done, addr.0x%04X, subaddr.0x%02X "
		       "value 0x%02X", address, subaddress, value)
	else
		DBG(5, "I2C write byte data failed, addr.0x%04X, "
		       "subaddr.0x%02X, value 0x%02X",
		    address, subaddress, value)

	return err;
}


/* SMBus protocol: S Addr Wr [A] Subaddr [A] P S Addr+1 Rd [A] [Value] NA P */
static int
w9968cf_i2c_adap_read_byte_data(struct w9968cf_device* cam,
				u16 address, u8 subaddress,
				u8* value)
{
	int err = 0;

	/* Serial data enable */
	err += w9968cf_write_sb(cam, 0x0013); /* don't change ! */

	err += w9968cf_smbus_start(cam);
	err += w9968cf_smbus_write_byte(cam, address);
	err += w9968cf_smbus_read_ack(cam);
	err += w9968cf_smbus_write_byte(cam, subaddress);
	err += w9968cf_smbus_read_ack(cam);
	err += w9968cf_smbus_stop(cam);
	err += w9968cf_smbus_start(cam);
	err += w9968cf_smbus_write_byte(cam, address + 1);
	err += w9968cf_smbus_read_ack(cam);
	err += w9968cf_smbus_read_byte(cam, value);
	err += w9968cf_smbus_write_ack(cam);
	err += w9968cf_smbus_stop(cam);

	/* Serial data disable */
	err += w9968cf_write_sb(cam, 0x0000);

	if (!err)
		DBG(5, "I2C read byte data done, addr.0x%04X, "
		       "subaddr.0x%02X, value 0x%02X",
		    address, subaddress, *value)
	else
		DBG(5, "I2C read byte data failed, addr.0x%04X, "
		       "subaddr.0x%02X, wrong value 0x%02X",
		    address, subaddress, *value)

	return err;
}


/* SMBus protocol: S Addr+1 Rd [A] [Value] NA P */
static int
w9968cf_i2c_adap_read_byte(struct w9968cf_device* cam,
			   u16 address, u8* value)
{
	int err = 0;

	/* Serial data enable */
	err += w9968cf_write_sb(cam, 0x0013);

	err += w9968cf_smbus_start(cam);
	err += w9968cf_smbus_write_byte(cam, address + 1);
	err += w9968cf_smbus_read_ack(cam);
	err += w9968cf_smbus_read_byte(cam, value);
	err += w9968cf_smbus_write_ack(cam);
	err += w9968cf_smbus_stop(cam);

	/* Serial data disable */
	err += w9968cf_write_sb(cam, 0x0000);

	if (!err)
		DBG(5, "I2C read byte done, addr.0x%04X, "
		       "value 0x%02X", address, *value)
	else
		DBG(5, "I2C read byte failed, addr.0x%04X, "
		       "wrong value 0x%02X", address, *value)

	return err;
}


/* SMBus protocol: S Addr Wr [A] Value [A] P */
static int
w9968cf_i2c_adap_write_byte(struct w9968cf_device* cam,
			    u16 address, u8 value)
{
	DBG(4, "i2c_write_byte() is an unsupported transfer mode")
	return -EINVAL;
}



/****************************************************************************
 * I2C interface to kernel                                                  *
 ****************************************************************************/

static int
w9968cf_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
		       unsigned short flags, char read_write, u8 command,
		       int size, union i2c_smbus_data *data)
{
	struct v4l2_device *v4l2_dev = i2c_get_adapdata(adapter);
	struct w9968cf_device *cam = to_cam(v4l2_dev);
	u8 i;
	int err = 0;

	if (size == I2C_SMBUS_BYTE) {
		/* Why addr <<= 1? See OVXXX0_SID defines in ovcamchip.h */
		addr <<= 1;

		if (read_write == I2C_SMBUS_WRITE)
			err = w9968cf_i2c_adap_write_byte(cam, addr, command);
		else if (read_write == I2C_SMBUS_READ)
			for (i = 1; i <= W9968CF_I2C_RW_RETRIES; i++) {
				err = w9968cf_i2c_adap_read_byte(cam, addr,
							 &data->byte);
				if (err) {
					if (w9968cf_smbus_refresh_bus(cam)) {
						err = -EIO;
						break;
					}
				} else
					break;
			}
	} else if (size == I2C_SMBUS_BYTE_DATA) {
		addr <<= 1;

		if (read_write == I2C_SMBUS_WRITE)
			err = w9968cf_i2c_adap_fastwrite_byte_data(cam, addr,
							  command, data->byte);
		else if (read_write == I2C_SMBUS_READ) {
			for (i = 1; i <= W9968CF_I2C_RW_RETRIES; i++) {
				err = w9968cf_i2c_adap_read_byte_data(cam,addr,
							 command, &data->byte);
				if (err) {
					if (w9968cf_smbus_refresh_bus(cam)) {
						err = -EIO;
						break;
					}
				} else
					break;
			}

		} else
			return -EINVAL;

	} else {
		DBG(4, "Unsupported I2C transfer mode (%d)", size)
		return -EINVAL;
	}
	return err;
}


static u32 w9968cf_i2c_func(struct i2c_adapter* adap)
{
	return I2C_FUNC_SMBUS_READ_BYTE |
	       I2C_FUNC_SMBUS_READ_BYTE_DATA  |
	       I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
}


static int w9968cf_i2c_init(struct w9968cf_device* cam)
{
	int err = 0;

	static struct i2c_algorithm algo = {
		.smbus_xfer =    w9968cf_i2c_smbus_xfer,
		.functionality = w9968cf_i2c_func,
	};

	static struct i2c_adapter adap = {
		.id =                I2C_HW_SMBUS_W9968CF,
		.owner =             THIS_MODULE,
		.algo =              &algo,
	};

	memcpy(&cam->i2c_adapter, &adap, sizeof(struct i2c_adapter));
	strcpy(cam->i2c_adapter.name, "w9968cf");
	cam->i2c_adapter.dev.parent = &cam->usbdev->dev;
	i2c_set_adapdata(&cam->i2c_adapter, &cam->v4l2_dev);

	DBG(6, "Registering I2C adapter with kernel...")

	err = i2c_add_adapter(&cam->i2c_adapter);
	if (err)
		DBG(1, "Failed to register the I2C adapter")
	else
		DBG(5, "I2C adapter registered")

	return err;
}



/****************************************************************************
 * Helper functions                                                         *
 ****************************************************************************/

/*--------------------------------------------------------------------------
  Turn on the LED on some webcams. A beep should be heard too.
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_turn_on_led(struct w9968cf_device* cam)
{
	int err = 0;

	err += w9968cf_write_reg(cam, 0xff00, 0x00); /* power-down */
	err += w9968cf_write_reg(cam, 0xbf17, 0x00); /* reset everything */
	err += w9968cf_write_reg(cam, 0xbf10, 0x00); /* normal operation */
	err += w9968cf_write_reg(cam, 0x0010, 0x01); /* serial bus, SDS high */
	err += w9968cf_write_reg(cam, 0x0000, 0x01); /* serial bus, SDS low */
	err += w9968cf_write_reg(cam, 0x0010, 0x01); /* ..high 'beep-beep' */

	if (err)
		DBG(2, "Couldn't turn on the LED")

	DBG(5, "LED turned on")

	return err;
}


/*--------------------------------------------------------------------------
  Write some registers for the device initialization.
  This function is called once on open().
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_init_chip(struct w9968cf_device* cam)
{
	unsigned long hw_bufsize = cam->maxwidth*cam->maxheight*2,
		      y0 = 0x0000,
		      u0 = y0 + hw_bufsize/2,
		      v0 = u0 + hw_bufsize/4,
		      y1 = v0 + hw_bufsize/4,
		      u1 = y1 + hw_bufsize/2,
		      v1 = u1 + hw_bufsize/4;
	int err = 0;

	err += w9968cf_write_reg(cam, 0xff00, 0x00); /* power off */
	err += w9968cf_write_reg(cam, 0xbf10, 0x00); /* power on */

	err += w9968cf_write_reg(cam, 0x405d, 0x03); /* DRAM timings */
	err += w9968cf_write_reg(cam, 0x0030, 0x04); /* SDRAM timings */

	err += w9968cf_write_reg(cam, y0 & 0xffff, 0x20); /* Y buf.0, low */
	err += w9968cf_write_reg(cam, y0 >> 16, 0x21);    /* Y buf.0, high */
	err += w9968cf_write_reg(cam, u0 & 0xffff, 0x24); /* U buf.0, low */
	err += w9968cf_write_reg(cam, u0 >> 16, 0x25);    /* U buf.0, high */
	err += w9968cf_write_reg(cam, v0 & 0xffff, 0x28); /* V buf.0, low */
	err += w9968cf_write_reg(cam, v0 >> 16, 0x29);    /* V buf.0, high */

	err += w9968cf_write_reg(cam, y1 & 0xffff, 0x22); /* Y buf.1, low */
	err += w9968cf_write_reg(cam, y1 >> 16, 0x23);    /* Y buf.1, high */
	err += w9968cf_write_reg(cam, u1 & 0xffff, 0x26); /* U buf.1, low */
	err += w9968cf_write_reg(cam, u1 >> 16, 0x27);    /* U buf.1, high */
	err += w9968cf_write_reg(cam, v1 & 0xffff, 0x2a); /* V buf.1, low */
	err += w9968cf_write_reg(cam, v1 >> 16, 0x2b);    /* V buf.1, high */

	err += w9968cf_write_reg(cam, y1 & 0xffff, 0x32); /* JPEG buf 0 low */
	err += w9968cf_write_reg(cam, y1 >> 16, 0x33);    /* JPEG buf 0 high */

	err += w9968cf_write_reg(cam, y1 & 0xffff, 0x34); /* JPEG buf 1 low */
	err += w9968cf_write_reg(cam, y1 >> 16, 0x35);    /* JPEG bug 1 high */

	err += w9968cf_write_reg(cam, 0x0000, 0x36);/* JPEG restart interval */
	err += w9968cf_write_reg(cam, 0x0804, 0x37);/*JPEG VLE FIFO threshold*/
	err += w9968cf_write_reg(cam, 0x0000, 0x38);/* disable hw up-scaling */
	err += w9968cf_write_reg(cam, 0x0000, 0x3f); /* JPEG/MCTL test data */

	err += w9968cf_set_picture(cam, cam->picture); /* this before */
	err += w9968cf_set_window(cam, cam->window);

	if (err)
		DBG(1, "Chip initialization failed")
	else
		DBG(5, "Chip successfully initialized")

	return err;
}


/*--------------------------------------------------------------------------
  Return non-zero if the palette is supported, 0 otherwise.
  --------------------------------------------------------------------------*/
static inline u16 w9968cf_valid_palette(u16 palette)
{
	u8 i = 0;
	while (w9968cf_formatlist[i].palette != 0) {
		if (palette == w9968cf_formatlist[i].palette)
			return palette;
		i++;
	}
	return 0;
}


/*--------------------------------------------------------------------------
  Return the depth corresponding to the given palette.
  Palette _must_ be supported !
  --------------------------------------------------------------------------*/
static inline u16 w9968cf_valid_depth(u16 palette)
{
	u8 i=0;
	while (w9968cf_formatlist[i].palette != palette)
		i++;

	return w9968cf_formatlist[i].depth;
}


/*--------------------------------------------------------------------------
  Return non-zero if the format requires decompression, 0 otherwise.
  --------------------------------------------------------------------------*/
static inline u8 w9968cf_need_decompression(u16 palette)
{
	u8 i = 0;
	while (w9968cf_formatlist[i].palette != 0) {
		if (palette == w9968cf_formatlist[i].palette)
			return w9968cf_formatlist[i].compression;
		i++;
	}
	return 0;
}


/*--------------------------------------------------------------------------
  Change the picture settings of the camera.
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int
w9968cf_set_picture(struct w9968cf_device* cam, struct video_picture pict)
{
	u16 fmt, hw_depth, hw_palette, reg_v = 0x0000;
	int err = 0;

	/* Make sure we are using a valid depth */
	pict.depth = w9968cf_valid_depth(pict.palette);

	fmt = pict.palette;

	hw_depth = pict.depth; /* depth used by the winbond chip */
	hw_palette = pict.palette; /* palette used by the winbond chip */

	/* VS & HS polarities */
	reg_v = (cam->vs_polarity << 12) | (cam->hs_polarity << 11);

	switch (fmt)
	{
		case VIDEO_PALETTE_UYVY:
			reg_v |= 0x0000;
			cam->vpp_flag = VPP_NONE;
			break;
		case VIDEO_PALETTE_YUV422P:
			reg_v |= 0x0002;
			cam->vpp_flag = VPP_DECOMPRESSION;
			break;
		case VIDEO_PALETTE_YUV420:
		case VIDEO_PALETTE_YUV420P:
			reg_v |= 0x0003;
			cam->vpp_flag = VPP_DECOMPRESSION;
			break;
		case VIDEO_PALETTE_YUYV:
		case VIDEO_PALETTE_YUV422:
			reg_v |= 0x0000;
			cam->vpp_flag = VPP_SWAP_YUV_BYTES;
			hw_palette = VIDEO_PALETTE_UYVY;
			break;
		/* Original video is used instead of RGBX palettes.
		   Software conversion later. */
		case VIDEO_PALETTE_GREY:
		case VIDEO_PALETTE_RGB555:
		case VIDEO_PALETTE_RGB565:
		case VIDEO_PALETTE_RGB24:
		case VIDEO_PALETTE_RGB32:
			reg_v |= 0x0000; /* UYVY 16 bit is used */
			hw_depth = 16;
			hw_palette = VIDEO_PALETTE_UYVY;
			cam->vpp_flag = VPP_UYVY_TO_RGBX;
			break;
	}

	/* NOTE: due to memory issues, it is better to disable the hardware
		 double buffering during compression */
	if (cam->double_buffer && !(cam->vpp_flag & VPP_DECOMPRESSION))
		reg_v |= 0x0080;

	if (cam->clamping)
		reg_v |= 0x0020;

	if (cam->filter_type == 1)
		reg_v |= 0x0008;
	else if (cam->filter_type == 2)
		reg_v |= 0x000c;

	if ((err = w9968cf_write_reg(cam, reg_v, 0x16)))
		goto error;

	if ((err = w9968cf_sensor_update_picture(cam, pict)))
		goto error;

	/* If all went well, update the device data structure */
	memcpy(&cam->picture, &pict, sizeof(pict));
	cam->hw_depth = hw_depth;
	cam->hw_palette = hw_palette;

	/* Settings changed, so we clear the frame buffers */
	memset(cam->frame[0].buffer, 0, cam->nbuffers*cam->frame[0].size);

	DBG(4, "Palette is %s, depth is %u bpp",
	    symbolic(v4l1_plist, pict.palette), pict.depth)

	return 0;

error:
	DBG(1, "Failed to change picture settings")
	return err;
}


/*--------------------------------------------------------------------------
  Change the capture area size of the camera.
  This function _must_ be called _after_ w9968cf_set_picture().
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int
w9968cf_set_window(struct w9968cf_device* cam, struct video_window win)
{
	u16 x, y, w, h, scx, scy, cw, ch, ax, ay;
	unsigned long fw, fh;
	struct ovcamchip_window s_win;
	int err = 0;

	/* Work around to avoid FP arithmetics */
	#define SC(x) ((x) << 10)
	#define UNSC(x) ((x) >> 10)

	/* Make sure we are using a supported resolution */
	if ((err = w9968cf_adjust_window_size(cam, (u16*)&win.width,
					      (u16*)&win.height)))
		goto error;

	/* Scaling factors */
	fw = SC(win.width) / cam->maxwidth;
	fh = SC(win.height) / cam->maxheight;

	/* Set up the width and height values used by the chip */
	if ((win.width > cam->maxwidth) || (win.height > cam->maxheight)) {
		cam->vpp_flag |= VPP_UPSCALE;
		/* Calculate largest w,h mantaining the same w/h ratio */
		w = (fw >= fh) ? cam->maxwidth : SC(win.width)/fh;
		h = (fw >= fh) ? SC(win.height)/fw : cam->maxheight;
		if (w < cam->minwidth) /* just in case */
			w = cam->minwidth;
		if (h < cam->minheight) /* just in case */
			h = cam->minheight;
	} else {
		cam->vpp_flag &= ~VPP_UPSCALE;
		w = win.width;
		h = win.height;
	}

	/* x,y offsets of the cropped area */
	scx = cam->start_cropx;
	scy = cam->start_cropy;

	/* Calculate cropped area manteining the right w/h ratio */
	if (cam->largeview && !(cam->vpp_flag & VPP_UPSCALE)) {
		cw = (fw >= fh) ? cam->maxwidth : SC(win.width)/fh;
		ch = (fw >= fh) ? SC(win.height)/fw : cam->maxheight;
	} else {
		cw = w;
		ch = h;
	}

	/* Setup the window of the sensor */
	s_win.format = VIDEO_PALETTE_UYVY;
	s_win.width = cam->maxwidth;
	s_win.height = cam->maxheight;
	s_win.quarter = 0; /* full progressive video */

	/* Center it */
	s_win.x = (s_win.width - cw) / 2;
	s_win.y = (s_win.height - ch) / 2;

	/* Clock divisor */
	if (cam->clockdiv >= 0)
		s_win.clockdiv = cam->clockdiv; /* manual override */
	else
		switch (cam->sensor) {
			case CC_OV6620:
				s_win.clockdiv = 0;
				break;
			case CC_OV6630:
				s_win.clockdiv = 0;
				break;
			case CC_OV76BE:
			case CC_OV7610:
			case CC_OV7620:
				s_win.clockdiv = 0;
				break;
			default:
				s_win.clockdiv = W9968CF_DEF_CLOCKDIVISOR;
		}

	/* We have to scale win.x and win.y offsets */
	if ( (cam->largeview && !(cam->vpp_flag & VPP_UPSCALE))
	     || (cam->vpp_flag & VPP_UPSCALE) ) {
		ax = SC(win.x)/fw;
		ay = SC(win.y)/fh;
	} else {
		ax = win.x;
		ay = win.y;
	}

	if ((ax + cw) > cam->maxwidth)
		ax = cam->maxwidth - cw;

	if ((ay + ch) > cam->maxheight)
		ay = cam->maxheight - ch;

	/* Adjust win.x, win.y */
	if ( (cam->largeview && !(cam->vpp_flag & VPP_UPSCALE))
	     || (cam->vpp_flag & VPP_UPSCALE) ) {
		win.x = UNSC(ax*fw);
		win.y = UNSC(ay*fh);
	} else {
		win.x = ax;
		win.y = ay;
	}

	/* Offsets used by the chip */
	x = ax + s_win.x;
	y = ay + s_win.y;

	/* Go ! */
	if ((err = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_S_MODE, &s_win)))
		goto error;

	err += w9968cf_write_reg(cam, scx + x, 0x10);
	err += w9968cf_write_reg(cam, scy + y, 0x11);
	err += w9968cf_write_reg(cam, scx + x + cw, 0x12);
	err += w9968cf_write_reg(cam, scy + y + ch, 0x13);
	err += w9968cf_write_reg(cam, w, 0x14);
	err += w9968cf_write_reg(cam, h, 0x15);

	/* JPEG width & height */
	err += w9968cf_write_reg(cam, w, 0x30);
	err += w9968cf_write_reg(cam, h, 0x31);

	/* Y & UV frame buffer strides (in WORD) */
	if (cam->vpp_flag & VPP_DECOMPRESSION) {
		err += w9968cf_write_reg(cam, w/2, 0x2c);
		err += w9968cf_write_reg(cam, w/4, 0x2d);
	} else
		err += w9968cf_write_reg(cam, w, 0x2c);

	if (err)
		goto error;

	/* If all went well, update the device data structure */
	memcpy(&cam->window, &win, sizeof(win));
	cam->hw_width = w;
	cam->hw_height = h;

	/* Settings changed, so we clear the frame buffers */
	memset(cam->frame[0].buffer, 0, cam->nbuffers*cam->frame[0].size);

	DBG(4, "The capture area is %dx%d, Offset (x,y)=(%u,%u)",
	    win.width, win.height, win.x, win.y)

	PDBGG("x=%u ,y=%u, w=%u, h=%u, ax=%u, ay=%u, s_win.x=%u, s_win.y=%u, "
	      "cw=%u, ch=%u, win.x=%u, win.y=%u, win.width=%u, win.height=%u",
	      x, y, w, h, ax, ay, s_win.x, s_win.y, cw, ch, win.x, win.y,
	      win.width, win.height)

	return 0;

error:
	DBG(1, "Failed to change the capture area size")
	return err;
}


/*--------------------------------------------------------------------------
  Adjust the asked values for window width and height.
  Return 0 on success, -1 otherwise.
  --------------------------------------------------------------------------*/
static int
w9968cf_adjust_window_size(struct w9968cf_device* cam, u16* width, u16* height)
{
	u16 maxw, maxh;

	if ((*width < cam->minwidth) || (*height < cam->minheight))
		return -ERANGE;

	maxw = cam->upscaling && !(cam->vpp_flag & VPP_DECOMPRESSION) &&
	       w9968cf_vpp ? max((u16)W9968CF_MAX_WIDTH, cam->maxwidth)
			   : cam->maxwidth;
	maxh = cam->upscaling && !(cam->vpp_flag & VPP_DECOMPRESSION) &&
	       w9968cf_vpp ? max((u16)W9968CF_MAX_HEIGHT, cam->maxheight)
			   : cam->maxheight;

	if (*width > maxw)
		*width = maxw;
	if (*height > maxh)
		*height = maxh;

	if (cam->vpp_flag & VPP_DECOMPRESSION) {
		*width  &= ~15L; /* multiple of 16 */
		*height &= ~15L;
	}

	PDBGG("Window size adjusted w=%u, h=%u ", *width, *height)

	return 0;
}


/*--------------------------------------------------------------------------
  Initialize the FIFO list of requested frames.
  --------------------------------------------------------------------------*/
static void w9968cf_init_framelist(struct w9968cf_device* cam)
{
	u8 i;

	for (i = 0; i < cam->nbuffers; i++) {
		cam->requested_frame[i] = NULL;
		cam->frame[i].queued = 0;
		cam->frame[i].status = F_UNUSED;
	}
}


/*--------------------------------------------------------------------------
  Add a frame in the FIFO list of requested frames.
  This function is called in process context.
  --------------------------------------------------------------------------*/
static void w9968cf_push_frame(struct w9968cf_device* cam, u8 f_num)
{
	u8 f;
	unsigned long lock_flags;

	spin_lock_irqsave(&cam->flist_lock, lock_flags);

	for (f=0; cam->requested_frame[f] != NULL; f++);
	cam->requested_frame[f] = &cam->frame[f_num];
	cam->frame[f_num].queued = 1;
	cam->frame[f_num].status = F_UNUSED; /* clear the status */

	spin_unlock_irqrestore(&cam->flist_lock, lock_flags);

	DBG(6, "Frame #%u pushed into the FIFO list. Position %u", f_num, f)
}


/*--------------------------------------------------------------------------
  Read, store and remove the first pointer in the FIFO list of requested
  frames. This function is called in interrupt context.
  --------------------------------------------------------------------------*/
static void
w9968cf_pop_frame(struct w9968cf_device* cam, struct w9968cf_frame_t** framep)
{
	u8 i;

	spin_lock(&cam->flist_lock);

	*framep = cam->requested_frame[0];

	/* Shift the list of pointers */
	for (i = 0; i < cam->nbuffers-1; i++)
		cam->requested_frame[i] = cam->requested_frame[i+1];
	cam->requested_frame[i] = NULL;

	spin_unlock(&cam->flist_lock);

	DBG(6,"Popped frame #%d from the list", (*framep)->number)
}


/*--------------------------------------------------------------------------
  High-level video post-processing routine on grabbed frames.
  Return 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int
w9968cf_postprocess_frame(struct w9968cf_device* cam,
			  struct w9968cf_frame_t* fr)
{
	void *pIn = fr->buffer, *pOut = cam->frame_vpp.buffer, *tmp;
	u16 w = cam->window.width,
	    h = cam->window.height,
	    d = cam->picture.depth,
	    fmt = cam->picture.palette,
	    rgb = cam->force_rgb,
	    hw_w = cam->hw_width,
	    hw_h = cam->hw_height,
	    hw_d = cam->hw_depth;
	int err = 0;

	#define _PSWAP(pIn, pOut) {tmp = (pIn); (pIn) = (pOut); (pOut) = tmp;}

	if (cam->vpp_flag & VPP_DECOMPRESSION) {
		memcpy(pOut, pIn, fr->length);
		_PSWAP(pIn, pOut)
		err = w9968cf_vpp->decode(pIn, fr->length, hw_w, hw_h, pOut);
		PDBGG("Compressed frame length: %lu",(unsigned long)fr->length)
		fr->length = (hw_w*hw_h*hw_d)/8;
		_PSWAP(pIn, pOut)
		if (err) {
			DBG(4, "An error occurred while decoding the frame: "
			       "%s", symbolic(decoder_errlist, err))
			return err;
		} else
			DBG(6, "Frame decoded")
	}

	if (cam->vpp_flag & VPP_SWAP_YUV_BYTES) {
		w9968cf_vpp->swap_yuvbytes(pIn, fr->length);
		DBG(6, "Original UYVY component ordering changed")
	}

	if (cam->vpp_flag & VPP_UPSCALE) {
		w9968cf_vpp->scale_up(pIn, pOut, hw_w, hw_h, hw_d, w, h);
		fr->length = (w*h*hw_d)/8;
		_PSWAP(pIn, pOut)
		DBG(6, "Vertical up-scaling done: %u,%u,%ubpp->%u,%u",
		    hw_w, hw_h, hw_d, w, h)
	}

	if (cam->vpp_flag & VPP_UYVY_TO_RGBX) {
		w9968cf_vpp->uyvy_to_rgbx(pIn, fr->length, pOut, fmt, rgb);
		fr->length = (w*h*d)/8;
		_PSWAP(pIn, pOut)
		DBG(6, "UYVY-16bit to %s conversion done",
		    symbolic(v4l1_plist, fmt))
	}

	if (pOut == fr->buffer)
		memcpy(fr->buffer, cam->frame_vpp.buffer, fr->length);

	return 0;
}



/****************************************************************************
 * Image sensor control routines                                            *
 ****************************************************************************/

static int
w9968cf_sensor_set_control(struct w9968cf_device* cam, int cid, int val)
{
	struct ovcamchip_control ctl;
	int err;

	ctl.id = cid;
	ctl.value = val;

	err = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_S_CTRL, &ctl);

	return err;
}


static int
w9968cf_sensor_get_control(struct w9968cf_device* cam, int cid, int* val)
{
	struct ovcamchip_control ctl;
	int err;

	ctl.id = cid;

	err = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_G_CTRL, &ctl);
	if (!err)
		*val = ctl.value;

	return err;
}


static int
w9968cf_sensor_cmd(struct w9968cf_device* cam, unsigned int cmd, void* arg)
{
	int rc;

	rc = v4l2_subdev_call(cam->sensor_sd, core, ioctl, cmd, arg);
	/* The I2C driver returns -EPERM on non-supported controls */
	return (rc < 0 && rc != -EPERM) ? rc : 0;
}


/*--------------------------------------------------------------------------
  Update some settings of the image sensor.
  Returns: 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_sensor_update_settings(struct w9968cf_device* cam)
{
	int err = 0;

	/* Auto brightness */
	err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_AUTOBRIGHT,
					 cam->auto_brt);
	if (err)
		return err;

	/* Auto exposure */
	err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_AUTOEXP,
					 cam->auto_exp);
	if (err)
		return err;

	/* Banding filter */
	err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_BANDFILT,
					 cam->bandfilt);
	if (err)
		return err;

	/* Light frequency */
	err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_FREQ,
					 cam->lightfreq);
	if (err)
		return err;

	/* Back light */
	err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_BACKLIGHT,
					 cam->backlight);
	if (err)
		return err;

	/* Mirror */
	err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_MIRROR,
					 cam->mirror);
	if (err)
		return err;

	return 0;
}


/*--------------------------------------------------------------------------
  Get some current picture settings from the image sensor and update the
  internal 'picture' structure of the camera.
  Returns: 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_sensor_get_picture(struct w9968cf_device* cam)
{
	int err, v;

	err = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_CONT, &v);
	if (err)
		return err;
	cam->picture.contrast = v;

	err = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_BRIGHT, &v);
	if (err)
		return err;
	cam->picture.brightness = v;

	err = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_SAT, &v);
	if (err)
		return err;
	cam->picture.colour = v;

	err = w9968cf_sensor_get_control(cam, OVCAMCHIP_CID_HUE, &v);
	if (err)
		return err;
	cam->picture.hue = v;

	DBG(5, "Got picture settings from the image sensor")

	PDBGG("Brightness, contrast, hue, colour, whiteness are "
	      "%u,%u,%u,%u,%u", cam->picture.brightness,cam->picture.contrast,
	      cam->picture.hue, cam->picture.colour, cam->picture.whiteness)

	return 0;
}


/*--------------------------------------------------------------------------
  Update picture settings of the image sensor.
  Returns: 0 on success, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int
w9968cf_sensor_update_picture(struct w9968cf_device* cam,
			      struct video_picture pict)
{
	int err = 0;

	if ((!cam->sensor_initialized)
	    || pict.contrast != cam->picture.contrast) {
		err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_CONT,
						 pict.contrast);
		if (err)
			goto fail;
		DBG(4, "Contrast changed from %u to %u",
		    cam->picture.contrast, pict.contrast)
		cam->picture.contrast = pict.contrast;
	}

	if (((!cam->sensor_initialized) ||
	    pict.brightness != cam->picture.brightness) && (!cam->auto_brt)) {
		err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_BRIGHT,
						 pict.brightness);
		if (err)
			goto fail;
		DBG(4, "Brightness changed from %u to %u",
		    cam->picture.brightness, pict.brightness)
		cam->picture.brightness = pict.brightness;
	}

	if ((!cam->sensor_initialized) || pict.colour != cam->picture.colour) {
		err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_SAT,
						 pict.colour);
		if (err)
			goto fail;
		DBG(4, "Colour changed from %u to %u",
		    cam->picture.colour, pict.colour)
		cam->picture.colour = pict.colour;
	}

	if ((!cam->sensor_initialized) || pict.hue != cam->picture.hue) {
		err = w9968cf_sensor_set_control(cam, OVCAMCHIP_CID_HUE,
						 pict.hue);
		if (err)
			goto fail;
		DBG(4, "Hue changed from %u to %u",
		    cam->picture.hue, pict.hue)
		cam->picture.hue = pict.hue;
	}

	return 0;

fail:
	DBG(4, "Failed to change sensor picture setting")
	return err;
}



/****************************************************************************
 * Camera configuration                                                     *
 ****************************************************************************/

/*--------------------------------------------------------------------------
  This function is called when a supported image sensor is detected.
  Return 0 if the initialization succeeds, a negative number otherwise.
  --------------------------------------------------------------------------*/
static int w9968cf_sensor_init(struct w9968cf_device* cam)
{
	int err = 0;

	if ((err = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_INITIALIZE,
				      &cam->monochrome)))
		goto error;

	if ((err = w9968cf_sensor_cmd(cam, OVCAMCHIP_CMD_Q_SUBTYPE,
				      &cam->sensor)))
		goto error;

	/* NOTE: Make sure width and height are a multiple of 16 */
	switch (v4l2_i2c_subdev_addr(cam->sensor_sd)) {
		case OV6xx0_SID:
			cam->maxwidth = 352;
			cam->maxheight = 288;
			cam->minwidth = 64;
			cam->minheight = 48;
			break;
		case OV7xx0_SID:
			cam->maxwidth = 640;
			cam->maxheight = 480;
			cam->minwidth = 64;
			cam->minheight = 48;
			break;
		default:
			DBG(1, "Not supported image sensor detected for %s",
			    symbolic(camlist, cam->id))
			return -EINVAL;
	}

	/* These values depend on the ones in the ovxxx0.c sources */
	switch (cam->sensor) {
		case CC_OV7620:
			cam->start_cropx = 287;
			cam->start_cropy = 35;
			/* Seems to work around a bug in the image sensor */
			cam->vs_polarity = 1;
			cam->hs_polarity = 1;
			break;
		default:
			cam->start_cropx = 320;
			cam->start_cropy = 35;
			cam->vs_polarity = 1;
			cam->hs_polarity = 0;
	}

	if ((err = w9968cf_sensor_update_settings(cam)))
		goto error;

	if ((err = w9968cf_sensor_update_picture(cam, cam->picture)))
		goto error;

	cam->sensor_initialized = 1;

	DBG(2, "%s image sensor initialized", symbolic(senlist, cam->sensor))
	return 0;

error:
	cam->sensor_initialized = 0;
	cam->sensor = CC_UNKNOWN;
	DBG(1, "Image sensor initialization failed for %s (/dev/video%d). "
	       "Try to detach and attach this device again",
	    symbolic(camlist, cam->id), cam->v4ldev->num)
	return err;
}


/*--------------------------------------------------------------------------
  Fill some basic fields in the main device data structure.
  This function is called once on w9968cf_usb_probe() for each recognized
  camera.
  --------------------------------------------------------------------------*/
static void
w9968cf_configure_camera(struct w9968cf_device* cam,
			 struct usb_device* udev,
			 enum w9968cf_model_id mod_id,
			 const unsigned short dev_nr)
{
	mutex_init(&cam->fileop_mutex);
	init_waitqueue_head(&cam->open);
	spin_lock_init(&cam->urb_lock);
	spin_lock_init(&cam->flist_lock);

	cam->users = 0;
	cam->disconnected = 0;
	cam->id = mod_id;
	cam->sensor = CC_UNKNOWN;
	cam->sensor_initialized = 0;

	/* Calculate the alternate setting number (from 1 to 16)
	   according to the 'packet_size' module parameter */
	if (packet_size[dev_nr] < W9968CF_MIN_PACKET_SIZE)
		packet_size[dev_nr] = W9968CF_MIN_PACKET_SIZE;
	for (cam->altsetting = 1;
	     packet_size[dev_nr] < wMaxPacketSize[cam->altsetting-1];
	     cam->altsetting++);

	cam->max_buffers = (max_buffers[dev_nr] < 2 ||
			    max_buffers[dev_nr] > W9968CF_MAX_BUFFERS)
			   ? W9968CF_BUFFERS : (u8)max_buffers[dev_nr];

	cam->double_buffer = (double_buffer[dev_nr] == 0 ||
			      double_buffer[dev_nr] == 1)
			     ? (u8)double_buffer[dev_nr]:W9968CF_DOUBLE_BUFFER;

	cam->clamping = (clamping[dev_nr] == 0 || clamping[dev_nr] == 1)
			? (u8)clamping[dev_nr] : W9968CF_CLAMPING;

	cam->filter_type = (filter_type[dev_nr] == 0 ||
			    filter_type[dev_nr] == 1 ||
			    filter_type[dev_nr] == 2)
			   ? (u8)filter_type[dev_nr] : W9968CF_FILTER_TYPE;

	cam->capture = 1;

	cam->largeview = (largeview[dev_nr] == 0 || largeview[dev_nr] == 1)
			 ? (u8)largeview[dev_nr] : W9968CF_LARGEVIEW;

	cam->decompression = (decompression[dev_nr] == 0 ||
			      decompression[dev_nr] == 1 ||
			      decompression[dev_nr] == 2)
			     ? (u8)decompression[dev_nr]:W9968CF_DECOMPRESSION;

	cam->upscaling = (upscaling[dev_nr] == 0 ||
			  upscaling[dev_nr] == 1)
			 ? (u8)upscaling[dev_nr] : W9968CF_UPSCALING;

	cam->auto_brt = (autobright[dev_nr] == 0 || autobright[dev_nr] == 1)
			? (u8)autobright[dev_nr] : W9968CF_AUTOBRIGHT;

	cam->auto_exp = (autoexp[dev_nr] == 0 || autoexp[dev_nr] == 1)
			? (u8)autoexp[dev_nr] : W9968CF_AUTOEXP;

	cam->lightfreq = (lightfreq[dev_nr] == 50 || lightfreq[dev_nr] == 60)
			 ? (u8)lightfreq[dev_nr] : W9968CF_LIGHTFREQ;

	cam->bandfilt = (bandingfilter[dev_nr] == 0 ||
			 bandingfilter[dev_nr] == 1)
			? (u8)bandingfilter[dev_nr] : W9968CF_BANDINGFILTER;

	cam->backlight = (backlight[dev_nr] == 0 || backlight[dev_nr] == 1)
			 ? (u8)backlight[dev_nr] : W9968CF_BACKLIGHT;

	cam->clockdiv = (clockdiv[dev_nr] == -1 || clockdiv[dev_nr] >= 0)
			? (s8)clockdiv[dev_nr] : W9968CF_CLOCKDIV;

	cam->mirror = (mirror[dev_nr] == 0 || mirror[dev_nr] == 1)
		      ? (u8)mirror[dev_nr] : W9968CF_MIRROR;

	cam->monochrome = (monochrome[dev_nr] == 0 || monochrome[dev_nr] == 1)
			  ? monochrome[dev_nr] : W9968CF_MONOCHROME;

	cam->picture.brightness = (u16)brightness[dev_nr];
	cam->picture.hue = (u16)hue[dev_nr];
	cam->picture.colour = (u16)colour[dev_nr];
	cam->picture.contrast = (u16)contrast[dev_nr];
	cam->picture.whiteness = (u16)whiteness[dev_nr];
	if (w9968cf_valid_palette((u16)force_palette[dev_nr])) {
		cam->picture.palette = (u16)force_palette[dev_nr];
		cam->force_palette = 1;
	} else {
		cam->force_palette = 0;
		if (cam->decompression == 0)
			cam->picture.palette = W9968CF_PALETTE_DECOMP_OFF;
		else if (cam->decompression == 1)
			cam->picture.palette = W9968CF_PALETTE_DECOMP_FORCE;
		else
			cam->picture.palette = W9968CF_PALETTE_DECOMP_ON;
	}
	cam->picture.depth = w9968cf_valid_depth(cam->picture.palette);

	cam->force_rgb = (force_rgb[dev_nr] == 0 || force_rgb[dev_nr] == 1)
			 ? (u8)force_rgb[dev_nr] : W9968CF_FORCE_RGB;

	cam->window.x = 0;
	cam->window.y = 0;
	cam->window.width = W9968CF_WIDTH;
	cam->window.height = W9968CF_HEIGHT;
	cam->window.chromakey = 0;
	cam->window.clipcount = 0;
	cam->window.flags = 0;

	DBG(3, "%s configured with settings #%u:",
	    symbolic(camlist, cam->id), dev_nr)

	DBG(3, "- Data packet size for USB isochrnous transfer: %u bytes",
	    wMaxPacketSize[cam->altsetting-1])

	DBG(3, "- Number of requested video frame buffers: %u",
	    cam->max_buffers)

	if (cam->double_buffer)
		DBG(3, "- Hardware double buffering enabled")
	else
		DBG(3, "- Hardware double buffering disabled")

	if (cam->filter_type == 0)
		DBG(3, "- Video filtering disabled")
	else if (cam->filter_type == 1)
		DBG(3, "- Video filtering enabled: type 1-2-1")
	else if (cam->filter_type == 2)
		DBG(3, "- Video filtering enabled: type 2-3-6-3-2")

	if (cam->clamping)
		DBG(3, "- Video data clamping (CCIR-601 format) enabled")
	else
		DBG(3, "- Video data clamping (CCIR-601 format) disabled")

	if (cam->largeview)
		DBG(3, "- Large view enabled")
	else
		DBG(3, "- Large view disabled")

	if ((cam->decompression) == 0 && (!cam->force_palette))
		DBG(3, "- Decompression disabled")
	else if ((cam->decompression) == 1 && (!cam->force_palette))
		DBG(3, "- Decompression forced")
	else if ((cam->decompression) == 2 && (!cam->force_palette))
		DBG(3, "- Decompression allowed")

	if (cam->upscaling)
		DBG(3, "- Software image scaling enabled")
	else
		DBG(3, "- Software image scaling disabled")

	if (cam->force_palette)
		DBG(3, "- Image palette forced to %s",
		    symbolic(v4l1_plist, cam->picture.palette))

	if (cam->force_rgb)
		DBG(3, "- RGB component ordering will be used instead of BGR")

	if (cam->auto_brt)
		DBG(3, "- Auto brightness enabled")
	else
		DBG(3, "- Auto brightness disabled")

	if (cam->auto_exp)
		DBG(3, "- Auto exposure enabled")
	else
		DBG(3, "- Auto exposure disabled")

	if (cam->backlight)
		DBG(3, "- Backlight exposure algorithm enabled")
	else
		DBG(3, "- Backlight exposure algorithm disabled")

	if (cam->mirror)
		DBG(3, "- Mirror enabled")
	else
		DBG(3, "- Mirror disabled")

	if (cam->bandfilt)
		DBG(3, "- Banding filter enabled")
	else
		DBG(3, "- Banding filter disabled")

	DBG(3, "- Power lighting frequency: %u", cam->lightfreq)

	if (cam->clockdiv == -1)
		DBG(3, "- Automatic clock divisor enabled")
	else
		DBG(3, "- Clock divisor: %d", cam->clockdiv)

	if (cam->monochrome)
		DBG(3, "- Image sensor used as monochrome")
	else
		DBG(3, "- Image sensor not used as monochrome")
}


/*--------------------------------------------------------------------------
  If the video post-processing module is not loaded, some parameters
  must be overridden.
  --------------------------------------------------------------------------*/
static void w9968cf_adjust_configuration(struct w9968cf_device* cam)
{
	if (!w9968cf_vpp) {
		if (cam->decompression == 1) {
			cam->decompression = 2;
			DBG(2, "Video post-processing module not found: "
			       "'decompression' parameter forced to 2")
		}
		if (cam->upscaling) {
			cam->upscaling = 0;
			DBG(2, "Video post-processing module not found: "
			       "'upscaling' parameter forced to 0")
		}
		if (cam->picture.palette != VIDEO_PALETTE_UYVY) {
			cam->force_palette = 0;
			DBG(2, "Video post-processing module not found: "
			       "'force_palette' parameter forced to 0")
		}
		cam->picture.palette = VIDEO_PALETTE_UYVY;
		cam->picture.depth = w9968cf_valid_depth(cam->picture.palette);
	}
}


/*--------------------------------------------------------------------------
  Release the resources used by the driver.
  This function is called on disconnect
  (or on close if deallocation has been deferred)
  --------------------------------------------------------------------------*/
static void w9968cf_release_resources(struct w9968cf_device* cam)
{
	mutex_lock(&w9968cf_devlist_mutex);

	DBG(2, "V4L device deregistered: /dev/video%d", cam->v4ldev->num)

	video_unregister_device(cam->v4ldev);
	list_del(&cam->v4llist);
	i2c_del_adapter(&cam->i2c_adapter);
	w9968cf_deallocate_memory(cam);
	kfree(cam->control_buffer);
	kfree(cam->data_buffer);
	v4l2_device_unregister(&cam->v4l2_dev);

	mutex_unlock(&w9968cf_devlist_mutex);
}



/****************************************************************************
 * Video4Linux interface                                                    *
 ****************************************************************************/

static int w9968cf_open(struct file *filp)
{
	struct w9968cf_device* cam;
	int err;

	/* This the only safe way to prevent race conditions with disconnect */
	if (!down_read_trylock(&w9968cf_disconnect))
		return -EAGAIN;

	cam = (struct w9968cf_device*)video_get_drvdata(video_devdata(filp));

	mutex_lock(&cam->dev_mutex);

	if (cam->sensor == CC_UNKNOWN) {
		DBG(2, "No supported image sensor has been detected by the "
		       "'ovcamchip' module for the %s (/dev/video%d). Make "
		       "sure it is loaded *before* (re)connecting the camera.",
		    symbolic(camlist, cam->id), cam->v4ldev->num)
		mutex_unlock(&cam->dev_mutex);
		up_read(&w9968cf_disconnect);
		return -ENODEV;
	}

	if (cam->users) {
		DBG(2, "%s (/dev/video%d) has been already occupied by '%s'",
		    symbolic(camlist, cam->id), cam->v4ldev->num, cam->command)
		if ((filp->f_flags & O_NONBLOCK)||(filp->f_flags & O_NDELAY)) {
			mutex_unlock(&cam->dev_mutex);
			up_read(&w9968cf_disconnect);
			return -EWOULDBLOCK;
		}
		mutex_unlock(&cam->dev_mutex);
		err = wait_event_interruptible_exclusive(cam->open,
							 cam->disconnected ||
							 !cam->users);
		if (err) {
			up_read(&w9968cf_disconnect);
			return err;
		}
		if (cam->disconnected) {
			up_read(&w9968cf_disconnect);
			return -ENODEV;
		}
		mutex_lock(&cam->dev_mutex);
	}

	DBG(5, "Opening '%s', /dev/video%d ...",
	    symbolic(camlist, cam->id), cam->v4ldev->num)

	cam->streaming = 0;
	cam->misconfigured = 0;

	w9968cf_adjust_configuration(cam);

	if ((err = w9968cf_allocate_memory(cam)))
		goto deallocate_memory;

	if ((err = w9968cf_init_chip(cam)))
		goto deallocate_memory;

	if ((err = w9968cf_start_transfer(cam)))
		goto deallocate_memory;

	filp->private_data = cam;

	cam->users++;
	strcpy(cam->command, current->comm);

	init_waitqueue_head(&cam->wait_queue);

	DBG(5, "Video device is open")

	mutex_unlock(&cam->dev_mutex);
	up_read(&w9968cf_disconnect);

	return 0;

deallocate_memory:
	w9968cf_deallocate_memory(cam);
	DBG(2, "Failed to open the video device")
	mutex_unlock(&cam->dev_mutex);
	up_read(&w9968cf_disconnect);
	return err;
}


static int w9968cf_release(struct file *filp)
{
	struct w9968cf_device* cam;

	cam = (struct w9968cf_device*)video_get_drvdata(video_devdata(filp));

	mutex_lock(&cam->dev_mutex); /* prevent disconnect() to be called */

	w9968cf_stop_transfer(cam);

	if (cam->disconnected) {
		w9968cf_release_resources(cam);
		mutex_unlock(&cam->dev_mutex);
		kfree(cam);
		return 0;
	}

	cam->users--;
	w9968cf_deallocate_memory(cam);
	wake_up_interruptible_nr(&cam->open, 1);

	DBG(5, "Video device closed")
	mutex_unlock(&cam->dev_mutex);
	return 0;
}


static ssize_t
w9968cf_read(struct file* filp, char __user * buf, size_t count, loff_t* f_pos)
{
	struct w9968cf_device* cam;
	struct w9968cf_frame_t* fr;
	int err = 0;

	cam = (struct w9968cf_device*)video_get_drvdata(video_devdata(filp));

	if (filp->f_flags & O_NONBLOCK)
		return -EWOULDBLOCK;

	if (mutex_lock_interruptible(&cam->fileop_mutex))
		return -ERESTARTSYS;

	if (cam->disconnected) {
		DBG(2, "Device not present")
		mutex_unlock(&cam->fileop_mutex);
		return -ENODEV;
	}

	if (cam->misconfigured) {
		DBG(2, "The camera is misconfigured. Close and open it again.")
		mutex_unlock(&cam->fileop_mutex);
		return -EIO;
	}

	if (!cam->frame[0].queued)
		w9968cf_push_frame(cam, 0);

	if (!cam->frame[1].queued)
		w9968cf_push_frame(cam, 1);

	err = wait_event_interruptible(cam->wait_queue,
				       cam->frame[0].status == F_READY ||
				       cam->frame[1].status == F_READY ||
				       cam->disconnected);
	if (err) {
		mutex_unlock(&cam->fileop_mutex);
		return err;
	}
	if (cam->disconnected) {
		mutex_unlock(&cam->fileop_mutex);
		return -ENODEV;
	}

	fr = (cam->frame[0].status == F_READY) ? &cam->frame[0]:&cam->frame[1];

	if (w9968cf_vpp)
		w9968cf_postprocess_frame(cam, fr);

	if (count > fr->length)
		count = fr->length;

	if (copy_to_user(buf, fr->buffer, count)) {
		fr->status = F_UNUSED;
		mutex_unlock(&cam->fileop_mutex);
		return -EFAULT;
	}
	*f_pos += count;

	fr->status = F_UNUSED;

	DBG(5, "%zu bytes read", count)

	mutex_unlock(&cam->fileop_mutex);
	return count;
}


static int w9968cf_mmap(struct file* filp, struct vm_area_struct *vma)
{
	struct w9968cf_device* cam = (struct w9968cf_device*)
				     video_get_drvdata(video_devdata(filp));
	unsigned long vsize = vma->vm_end - vma->vm_start,
		      psize = cam->nbuffers * cam->frame[0].size,
		      start = vma->vm_start,
		      pos = (unsigned long)cam->frame[0].buffer,
		      page;

	if (cam->disconnected) {
		DBG(2, "Device not present")
		return -ENODEV;
	}

	if (cam->misconfigured) {
		DBG(2, "The camera is misconfigured. Close and open it again")
		return -EIO;
	}

	PDBGG("mmapping %lu bytes...", vsize)

	if (vsize > psize - (vma->vm_pgoff << PAGE_SHIFT))
		return -EINVAL;

	while (vsize > 0) {
		page = vmalloc_to_pfn((void *)pos);
		if (remap_pfn_range(vma, start, page + vma->vm_pgoff,
						PAGE_SIZE, vma->vm_page_prot))
			return -EAGAIN;
		start += PAGE_SIZE;
		pos += PAGE_SIZE;
		vsize -= PAGE_SIZE;
	}

	DBG(5, "mmap method successfully called")
	return 0;
}


static long
w9968cf_ioctl(struct file *filp,
	      unsigned int cmd, unsigned long arg)
{
	struct w9968cf_device* cam;
	long err;

	cam = (struct w9968cf_device*)video_get_drvdata(video_devdata(filp));

	if (mutex_lock_interruptible(&cam->fileop_mutex))
		return -ERESTARTSYS;

	if (cam->disconnected) {
		DBG(2, "Device not present")
		mutex_unlock(&cam->fileop_mutex);
		return -ENODEV;
	}

	if (cam->misconfigured) {
		DBG(2, "The camera is misconfigured. Close and open it again.")
		mutex_unlock(&cam->fileop_mutex);
		return -EIO;
	}

	err = w9968cf_v4l_ioctl(filp, cmd, (void __user *)arg);

	mutex_unlock(&cam->fileop_mutex);
	return err;
}


static long w9968cf_v4l_ioctl(struct file *filp,
			     unsigned int cmd, void __user *arg)
{
	struct w9968cf_device* cam;
	const char* v4l1_ioctls[] = {
		"?", "CGAP", "GCHAN", "SCHAN", "GTUNER", "STUNER",
		"GPICT", "SPICT", "CCAPTURE", "GWIN", "SWIN", "GFBUF",
		"SFBUF", "KEY", "GFREQ", "SFREQ", "GAUDIO", "SAUDIO",
		"SYNC", "MCAPTURE", "GMBUF", "GUNIT", "GCAPTURE", "SCAPTURE",
		"SPLAYMODE", "SWRITEMODE", "GPLAYINFO", "SMICROCODE",
		"GVBIFMT", "SVBIFMT"
	};

	#define V4L1_IOCTL(cmd) \
		((_IOC_NR((cmd)) < ARRAY_SIZE(v4l1_ioctls)) ? \
		v4l1_ioctls[_IOC_NR((cmd))] : "?")

	cam = (struct w9968cf_device*)video_get_drvdata(video_devdata(filp));

	switch (cmd) {

	case VIDIOCGCAP: /* get video capability */
	{
		struct video_capability cap = {
			.type = VID_TYPE_CAPTURE | VID_TYPE_SCALES,
			.channels = 1,
			.audios = 0,
			.minwidth = cam->minwidth,
			.minheight = cam->minheight,
		};
		sprintf(cap.name, "W996[87]CF USB Camera #%d",
			cam->v4ldev->num);
		cap.maxwidth = (cam->upscaling && w9968cf_vpp)
			       ? max((u16)W9968CF_MAX_WIDTH, cam->maxwidth)
				 : cam->maxwidth;
		cap.maxheight = (cam->upscaling && w9968cf_vpp)
				? max((u16)W9968CF_MAX_HEIGHT, cam->maxheight)
				  : cam->maxheight;

		if (copy_to_user(arg, &cap, sizeof(cap)))
			return -EFAULT;

		DBG(5, "VIDIOCGCAP successfully called")
		return 0;
	}

	case VIDIOCGCHAN: /* get video channel informations */
	{
		struct video_channel chan;
		if (copy_from_user(&chan, arg, sizeof(chan)))
			return -EFAULT;

		if (chan.channel != 0)
			return -EINVAL;

		strcpy(chan.name, "Camera");
		chan.tuners = 0;
		chan.flags = 0;
		chan.type = VIDEO_TYPE_CAMERA;
		chan.norm = VIDEO_MODE_AUTO;

		if (copy_to_user(arg, &chan, sizeof(chan)))
			return -EFAULT;

		DBG(5, "VIDIOCGCHAN successfully called")
		return 0;
	}

	case VIDIOCSCHAN: /* set active channel */
	{
		struct video_channel chan;

		if (copy_from_user(&chan, arg, sizeof(chan)))
			return -EFAULT;

		if (chan.channel != 0)
			return -EINVAL;

		DBG(5, "VIDIOCSCHAN successfully called")
		return 0;
	}

	case VIDIOCGPICT: /* get image properties of the picture */
	{
		if (w9968cf_sensor_get_picture(cam))
			return -EIO;

		if (copy_to_user(arg, &cam->picture, sizeof(cam->picture)))
			return -EFAULT;

		DBG(5, "VIDIOCGPICT successfully called")
		return 0;
	}

	case VIDIOCSPICT: /* change picture settings */
	{
		struct video_picture pict;
		int err = 0;

		if (copy_from_user(&pict, arg, sizeof(pict)))
			return -EFAULT;

		if ( (cam->force_palette || !w9968cf_vpp)
		     && pict.palette != cam->picture.palette ) {
			DBG(4, "Palette %s rejected: only %s is allowed",
			    symbolic(v4l1_plist, pict.palette),
			    symbolic(v4l1_plist, cam->picture.palette))
			return -EINVAL;
		}

		if (!w9968cf_valid_palette(pict.palette)) {
			DBG(4, "Palette %s not supported. VIDIOCSPICT failed",
			    symbolic(v4l1_plist, pict.palette))
			return -EINVAL;
		}

		if (!cam->force_palette) {
		   if (cam->decompression == 0) {
		      if (w9968cf_need_decompression(pict.palette)) {
			 DBG(4, "Decompression disabled: palette %s is not "
				"allowed. VIDIOCSPICT failed",
			     symbolic(v4l1_plist, pict.palette))
			 return -EINVAL;
		      }
		   } else if (cam->decompression == 1) {
		      if (!w9968cf_need_decompression(pict.palette)) {
			 DBG(4, "Decompression forced: palette %s is not "
				"allowed. VIDIOCSPICT failed",
			     symbolic(v4l1_plist, pict.palette))
			 return -EINVAL;
		      }
		   }
		}

		if (pict.depth != w9968cf_valid_depth(pict.palette)) {
			DBG(4, "Requested depth %u bpp is not valid for %s "
			       "palette: ignored and changed to %u bpp",
			    pict.depth, symbolic(v4l1_plist, pict.palette),
			    w9968cf_valid_depth(pict.palette))
			pict.depth = w9968cf_valid_depth(pict.palette);
		}

		if (pict.palette != cam->picture.palette) {
			if(*cam->requested_frame
			   || cam->frame_current->queued) {
				err = wait_event_interruptible
				      ( cam->wait_queue,
					cam->disconnected ||
					(!*cam->requested_frame &&
					 !cam->frame_current->queued) );
				if (err)
					return err;
				if (cam->disconnected)
					return -ENODEV;
			}

			if (w9968cf_stop_transfer(cam))
				goto ioctl_fail;

			if (w9968cf_set_picture(cam, pict))
				goto ioctl_fail;

			if (w9968cf_start_transfer(cam))
				goto ioctl_fail;

		} else if (w9968cf_sensor_update_picture(cam, pict))
			return -EIO;


		DBG(5, "VIDIOCSPICT successfully called")
		return 0;
	}

	case VIDIOCSWIN: /* set capture area */
	{
		struct video_window win;
		int err = 0;

		if (copy_from_user(&win, arg, sizeof(win)))
			return -EFAULT;

		DBG(6, "VIDIOCSWIN called: clipcount=%d, flags=%u, "
		       "x=%u, y=%u, %ux%u", win.clipcount, win.flags,
		    win.x, win.y, win.width, win.height)

		if (win.clipcount != 0 || win.flags != 0)
			return -EINVAL;

		if ((err = w9968cf_adjust_window_size(cam, (u16*)&win.width,
						      (u16*)&win.height))) {
			DBG(4, "Resolution not supported (%ux%u). "
			       "VIDIOCSWIN failed", win.width, win.height)
			return err;
		}

		if (win.x != cam->window.x ||
		    win.y != cam->window.y ||
		    win.width != cam->window.width ||
		    win.height != cam->window.height) {
			if(*cam->requested_frame
			   || cam->frame_current->queued) {
				err = wait_event_interruptible
				      ( cam->wait_queue,
					cam->disconnected ||
					(!*cam->requested_frame &&
					 !cam->frame_current->queued) );
				if (err)
					return err;
				if (cam->disconnected)
					return -ENODEV;
			}

			if (w9968cf_stop_transfer(cam))
				goto ioctl_fail;

			/* This _must_ be called before set_window() */
			if (w9968cf_set_picture(cam, cam->picture))
				goto ioctl_fail;

			if (w9968cf_set_window(cam, win))
				goto ioctl_fail;

			if (w9968cf_start_transfer(cam))
				goto ioctl_fail;
		}

		DBG(5, "VIDIOCSWIN successfully called. ")
		return 0;
	}

	case VIDIOCGWIN: /* get current window properties */
	{
		if (copy_to_user(arg,&cam->window,sizeof(struct video_window)))
			return -EFAULT;

		DBG(5, "VIDIOCGWIN successfully called")
		return 0;
	}

	case VIDIOCGMBUF: /* request for memory (mapped) buffer */
	{
		struct video_mbuf mbuf;
		u8 i;

		mbuf.size = cam->nbuffers * cam->frame[0].size;
		mbuf.frames = cam->nbuffers;
		for (i = 0; i < cam->nbuffers; i++)
			mbuf.offsets[i] = (unsigned long)cam->frame[i].buffer -
					  (unsigned long)cam->frame[0].buffer;

		if (copy_to_user(arg, &mbuf, sizeof(mbuf)))
			return -EFAULT;

		DBG(5, "VIDIOCGMBUF successfully called")
		return 0;
	}

	case VIDIOCMCAPTURE: /* start the capture to a frame */
	{
		struct video_mmap mmap;
		struct w9968cf_frame_t* fr;
		int err = 0;

		if (copy_from_user(&mmap, arg, sizeof(mmap)))
			return -EFAULT;

		DBG(6, "VIDIOCMCAPTURE called: frame #%u, format=%s, %dx%d",
		    mmap.frame, symbolic(v4l1_plist, mmap.format),
		    mmap.width, mmap.height)

		if (mmap.frame >= cam->nbuffers) {
			DBG(4, "Invalid frame number (%u). "
			       "VIDIOCMCAPTURE failed", mmap.frame)
			return -EINVAL;
		}

		if (mmap.format!=cam->picture.palette &&
		    (cam->force_palette || !w9968cf_vpp)) {
			DBG(4, "Palette %s rejected: only %s is allowed",
			    symbolic(v4l1_plist, mmap.format),
			    symbolic(v4l1_plist, cam->picture.palette))
			return -EINVAL;
		}

		if (!w9968cf_valid_palette(mmap.format)) {
			DBG(4, "Palette %s not supported. "
			       "VIDIOCMCAPTURE failed",
			    symbolic(v4l1_plist, mmap.format))
			return -EINVAL;
		}

		if (!cam->force_palette) {
		   if (cam->decompression == 0) {
		      if (w9968cf_need_decompression(mmap.format)) {
			 DBG(4, "Decompression disabled: palette %s is not "
				"allowed. VIDIOCSPICT failed",
			     symbolic(v4l1_plist, mmap.format))
			 return -EINVAL;
		      }
		   } else if (cam->decompression == 1) {
		      if (!w9968cf_need_decompression(mmap.format)) {
			 DBG(4, "Decompression forced: palette %s is not "
				"allowed. VIDIOCSPICT failed",
			     symbolic(v4l1_plist, mmap.format))
			 return -EINVAL;
		      }
		   }
		}

		if ((err = w9968cf_adjust_window_size(cam, (u16*)&mmap.width,
						      (u16*)&mmap.height))) {
			DBG(4, "Resolution not supported (%dx%d). "
			       "VIDIOCMCAPTURE failed",
			    mmap.width, mmap.height)
			return err;
		}

		fr = &cam->frame[mmap.frame];

		if (mmap.width  != cam->window.width ||
		    mmap.height != cam->window.height ||
		    mmap.format != cam->picture.palette) {

			struct video_window win;
			struct video_picture pict;

			if(*cam->requested_frame
			   || cam->frame_current->queued) {
				DBG(6, "VIDIOCMCAPTURE. Change settings for "
				       "frame #%u: %dx%d, format %s. Wait...",
				    mmap.frame, mmap.width, mmap.height,
				    symbolic(v4l1_plist, mmap.format))
				err = wait_event_interruptible
				      ( cam->wait_queue,
					cam->disconnected ||
					(!*cam->requested_frame &&
					 !cam->frame_current->queued) );
				if (err)
					return err;
				if (cam->disconnected)
					return -ENODEV;
			}

			memcpy(&win, &cam->window, sizeof(win));
			memcpy(&pict, &cam->picture, sizeof(pict));
			win.width = mmap.width;
			win.height = mmap.height;
			pict.palette = mmap.format;

			if (w9968cf_stop_transfer(cam))
				goto ioctl_fail;

			/* This before set_window */
			if (w9968cf_set_picture(cam, pict))
				goto ioctl_fail;

			if (w9968cf_set_window(cam, win))
				goto ioctl_fail;

			if (w9968cf_start_transfer(cam))
				goto ioctl_fail;

		} else 	if (fr->queued) {

			DBG(6, "Wait until frame #%u is free", mmap.frame)

			err = wait_event_interruptible(cam->wait_queue,
						       cam->disconnected ||
						       (!fr->queued));
			if (err)
				return err;
			if (cam->disconnected)
				return -ENODEV;
		}

		w9968cf_push_frame(cam, mmap.frame);
		DBG(5, "VIDIOCMCAPTURE(%u): successfully called", mmap.frame)
		return 0;
	}

	case VIDIOCSYNC: /* wait until the capture of a frame is finished */
	{
		unsigned int f_num;
		struct w9968cf_frame_t* fr;
		int err = 0;

		if (copy_from_user(&f_num, arg, sizeof(f_num)))
			return -EFAULT;

		if (f_num >= cam->nbuffers) {
			DBG(4, "Invalid frame number (%u). "
			       "VIDIOCMCAPTURE failed", f_num)
			return -EINVAL;
		}

		DBG(6, "VIDIOCSYNC called for frame #%u", f_num)

		fr = &cam->frame[f_num];

		switch (fr->status) {
		case F_UNUSED:
			if (!fr->queued) {
				DBG(4, "VIDIOSYNC: Frame #%u not requested!",
				    f_num)
				return -EFAULT;
			}
		case F_ERROR:
		case F_GRABBING:
			err = wait_event_interruptible(cam->wait_queue,
						       (fr->status == F_READY)
						       || cam->disconnected);
			if (err)
				return err;
			if (cam->disconnected)
				return -ENODEV;
			break;
		case F_READY:
			break;
		}

		if (w9968cf_vpp)
			w9968cf_postprocess_frame(cam, fr);

		fr->status = F_UNUSED;

		DBG(5, "VIDIOCSYNC(%u) successfully called", f_num)
		return 0;
	}

	case VIDIOCGUNIT:/* report the unit numbers of the associated devices*/
	{
		struct video_unit unit = {
			.video = cam->v4ldev->minor,
			.vbi = VIDEO_NO_UNIT,
			.radio = VIDEO_NO_UNIT,
			.audio = VIDEO_NO_UNIT,
			.teletext = VIDEO_NO_UNIT,
		};

		if (copy_to_user(arg, &unit, sizeof(unit)))
			return -EFAULT;

		DBG(5, "VIDIOCGUNIT successfully called")
		return 0;
	}

	case VIDIOCKEY:
		return 0;

	case VIDIOCGFBUF:
	{
		if (clear_user(arg, sizeof(struct video_buffer)))
			return -EFAULT;

		DBG(5, "VIDIOCGFBUF successfully called")
		return 0;
	}

	case VIDIOCGTUNER:
	{
		struct video_tuner tuner;
		if (copy_from_user(&tuner, arg, sizeof(tuner)))
			return -EFAULT;

		if (tuner.tuner != 0)
			return -EINVAL;

		strcpy(tuner.name, "no_tuner");
		tuner.rangelow = 0;
		tuner.rangehigh = 0;
		tuner.flags = VIDEO_TUNER_NORM;
		tuner.mode = VIDEO_MODE_AUTO;
		tuner.signal = 0xffff;

		if (copy_to_user(arg, &tuner, sizeof(tuner)))
			return -EFAULT;

		DBG(5, "VIDIOCGTUNER successfully called")
		return 0;
	}

	case VIDIOCSTUNER:
	{
		struct video_tuner tuner;
		if (copy_from_user(&tuner, arg, sizeof(tuner)))
			return -EFAULT;

		if (tuner.tuner != 0)
			return -EINVAL;

		if (tuner.mode != VIDEO_MODE_AUTO)
			return -EINVAL;

		DBG(5, "VIDIOCSTUNER successfully called")
		return 0;
	}

	case VIDIOCSFBUF:
	case VIDIOCCAPTURE:
	case VIDIOCGFREQ:
	case VIDIOCSFREQ:
	case VIDIOCGAUDIO:
	case VIDIOCSAUDIO:
	case VIDIOCSPLAYMODE:
	case VIDIOCSWRITEMODE:
	case VIDIOCGPLAYINFO:
	case VIDIOCSMICROCODE:
	case VIDIOCGVBIFMT:
	case VIDIOCSVBIFMT:
		DBG(4, "Unsupported V4L1 IOCtl: VIDIOC%s "
		       "(type 0x%01X, "
		       "n. 0x%01X, "
		       "dir. 0x%01X, "
		       "size 0x%02X)",
		    V4L1_IOCTL(cmd),
		    _IOC_TYPE(cmd),_IOC_NR(cmd),_IOC_DIR(cmd),_IOC_SIZE(cmd))

		return -EINVAL;

	default:
		DBG(4, "Invalid V4L1 IOCtl: VIDIOC%s "
		       "type 0x%01X, "
		       "n. 0x%01X, "
		       "dir. 0x%01X, "
		       "size 0x%02X",
		    V4L1_IOCTL(cmd),
		    _IOC_TYPE(cmd),_IOC_NR(cmd),_IOC_DIR(cmd),_IOC_SIZE(cmd))

		return -ENOIOCTLCMD;

	} /* end of switch */

ioctl_fail:
	cam->misconfigured = 1;
	DBG(1, "VIDIOC%s failed because of hardware problems. "
	       "To use the camera, close and open it again.", V4L1_IOCTL(cmd))
	return -EFAULT;
}


static const struct v4l2_file_operations w9968cf_fops = {
	.owner =   THIS_MODULE,
	.open =    w9968cf_open,
	.release = w9968cf_release,
	.read =    w9968cf_read,
	.ioctl =   w9968cf_ioctl,
	.mmap =    w9968cf_mmap,
};



/****************************************************************************
 * USB probe and V4L registration, disconnect and id_table[] definition     *
 ****************************************************************************/

static int
w9968cf_usb_probe(struct usb_interface* intf, const struct usb_device_id* id)
{
	struct usb_device *udev = interface_to_usbdev(intf);
	struct w9968cf_device* cam;
	int err = 0;
	enum w9968cf_model_id mod_id;
	struct list_head* ptr;
	u8 sc = 0; /* number of simultaneous cameras */
	static unsigned short dev_nr; /* 0 - we are handling device number n */
	static unsigned short addrs[] = {
		OV7xx0_SID,
		OV6xx0_SID,
		I2C_CLIENT_END
	};

	if (le16_to_cpu(udev->descriptor.idVendor)  == winbond_id_table[0].idVendor &&
	    le16_to_cpu(udev->descriptor.idProduct) == winbond_id_table[0].idProduct)
		mod_id = W9968CF_MOD_CLVBWGP; /* see camlist[] table */
	else if (le16_to_cpu(udev->descriptor.idVendor)  == winbond_id_table[1].idVendor &&
		 le16_to_cpu(udev->descriptor.idProduct) == winbond_id_table[1].idProduct)
		mod_id = W9968CF_MOD_GENERIC; /* see camlist[] table */
	else
		return -ENODEV;

	cam = (struct w9968cf_device*)
		  kzalloc(sizeof(struct w9968cf_device), GFP_KERNEL);
	if (!cam)
		return -ENOMEM;

	err = v4l2_device_register(&udev->dev, &cam->v4l2_dev);
	if (err)
		goto fail0;

	mutex_init(&cam->dev_mutex);
	mutex_lock(&cam->dev_mutex);

	cam->usbdev = udev;

	DBG(2, "%s detected", symbolic(camlist, mod_id))

	if (simcams > W9968CF_MAX_DEVICES)
		simcams = W9968CF_SIMCAMS;

	/* How many cameras are connected ? */
	mutex_lock(&w9968cf_devlist_mutex);
	list_for_each(ptr, &w9968cf_dev_list)
		sc++;
	mutex_unlock(&w9968cf_devlist_mutex);

	if (sc >= simcams) {
		DBG(2, "Device rejected: too many connected cameras "
		       "(max. %u)", simcams)
		err = -EPERM;
		goto fail;
	}


	/* Allocate 2 bytes of memory for camera control USB transfers */
	if (!(cam->control_buffer = kzalloc(2, GFP_KERNEL))) {
		DBG(1,"Couldn't allocate memory for camera control transfers")
		err = -ENOMEM;
		goto fail;
	}

	/* Allocate 8 bytes of memory for USB data transfers to the FSB */
	if (!(cam->data_buffer = kzalloc(8, GFP_KERNEL))) {
		DBG(1, "Couldn't allocate memory for data "
		       "transfers to the FSB")
		err = -ENOMEM;
		goto fail;
	}

	/* Register the V4L device */
	cam->v4ldev = video_device_alloc();
	if (!cam->v4ldev) {
		DBG(1, "Could not allocate memory for a V4L structure")
		err = -ENOMEM;
		goto fail;
	}

	strcpy(cam->v4ldev->name, symbolic(camlist, mod_id));
	cam->v4ldev->fops = &w9968cf_fops;
	cam->v4ldev->minor = video_nr[dev_nr];
	cam->v4ldev->release = video_device_release;
	video_set_drvdata(cam->v4ldev, cam);
	cam->v4ldev->v4l2_dev = &cam->v4l2_dev;

	err = video_register_device(cam->v4ldev, VFL_TYPE_GRABBER,
				    video_nr[dev_nr]);
	if (err) {
		DBG(1, "V4L device registration failed")
		if (err == -ENFILE && video_nr[dev_nr] == -1)
			DBG(2, "Couldn't find a free /dev/videoX node")
		video_nr[dev_nr] = -1;
		dev_nr = (dev_nr < W9968CF_MAX_DEVICES-1) ? dev_nr+1 : 0;
		goto fail;
	}

	DBG(2, "V4L device registered as /dev/video%d", cam->v4ldev->num)

	/* Set some basic constants */
	w9968cf_configure_camera(cam, udev, mod_id, dev_nr);

	/* Add a new entry into the list of V4L registered devices */
	mutex_lock(&w9968cf_devlist_mutex);
	list_add(&cam->v4llist, &w9968cf_dev_list);
	mutex_unlock(&w9968cf_devlist_mutex);
	dev_nr = (dev_nr < W9968CF_MAX_DEVICES-1) ? dev_nr+1 : 0;

	w9968cf_turn_on_led(cam);

	w9968cf_i2c_init(cam);
	cam->sensor_sd = v4l2_i2c_new_probed_subdev(&cam->i2c_adapter,
			"ovcamchip", "ovcamchip", addrs);

	usb_set_intfdata(intf, cam);
	mutex_unlock(&cam->dev_mutex);

	err = w9968cf_sensor_init(cam);
	return 0;

fail: /* Free unused memory */
	kfree(cam->control_buffer);
	kfree(cam->data_buffer);
	if (cam->v4ldev)
		video_device_release(cam->v4ldev);
	mutex_unlock(&cam->dev_mutex);
	v4l2_device_unregister(&cam->v4l2_dev);
fail0:
	kfree(cam);
	return err;
}


static void w9968cf_usb_disconnect(struct usb_interface* intf)
{
	struct w9968cf_device* cam =
	   (struct w9968cf_device*)usb_get_intfdata(intf);

	if (cam) {
		down_write(&w9968cf_disconnect);
		/* Prevent concurrent accesses to data */
		mutex_lock(&cam->dev_mutex);

		cam->disconnected = 1;

		DBG(2, "Disconnecting %s...", symbolic(camlist, cam->id));

		v4l2_device_disconnect(&cam->v4l2_dev);

		wake_up_interruptible_all(&cam->open);

		if (cam->users) {
			DBG(2, "The device is open (/dev/video%d)! "
			       "Process name: %s. Deregistration and memory "
			       "deallocation are deferred on close.",
			    cam->v4ldev->num, cam->command)
			cam->misconfigured = 1;
			w9968cf_stop_transfer(cam);
			wake_up_interruptible(&cam->wait_queue);
		} else
			w9968cf_release_resources(cam);

		mutex_unlock(&cam->dev_mutex);
		up_write(&w9968cf_disconnect);

		if (!cam->users) {
			kfree(cam);
		}
	}
}


static struct usb_driver w9968cf_usb_driver = {
	.name =       "w9968cf",
	.id_table =   winbond_id_table,
	.probe =      w9968cf_usb_probe,
	.disconnect = w9968cf_usb_disconnect,
};



/****************************************************************************
 * Module init, exit and intermodule communication                          *
 ****************************************************************************/

static int __init w9968cf_module_init(void)
{
	int err;

	KDBG(2, W9968CF_MODULE_NAME" "W9968CF_MODULE_VERSION)
	KDBG(3, W9968CF_MODULE_AUTHOR)

	if ((err = usb_register(&w9968cf_usb_driver)))
		return err;

	return 0;
}


static void __exit w9968cf_module_exit(void)
{
	/* w9968cf_usb_disconnect() will be called */
	usb_deregister(&w9968cf_usb_driver);

	KDBG(2, W9968CF_MODULE_NAME" deregistered")
}


module_init(w9968cf_module_init);
module_exit(w9968cf_module_exit);

OpenPOWER on IntegriCloud