/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * Copyright (C) 2019, Google Inc. * * format_convert.cpp - qcam - Convert buffer to RGB */ #include #include #include #include "format_converter.h" #define RGBSHIFT 8 #ifndef MAX #define MAX(a,b) ((a)>(b)?(a):(b)) #endif #ifndef MIN #define MIN(a,b) ((a)<(b)?(a):(b)) #endif #ifndef CLAMP #define CLAMP(a,low,high) MAX((low),MIN((high),(a))) #endif #ifndef CLIP #define CLIP(x) CLAMP(x,0,255) #endif int FormatConverter::configure(unsigned int format, unsigned int width, unsigned int height) { switch (format) { case DRM_FORMAT_NV12: formatFamily_ = NV; horzSubSample_ = 2; vertSubSample_ = 2; nvSwap_ = false; break; case DRM_FORMAT_NV21: formatFamily_ = NV; horzSubSample_ = 2; vertSubSample_ = 2; nvSwap_ = true; break; case DRM_FORMAT_NV16: formatFamily_ = NV; horzSubSample_ = 2; vertSubSample_ = 1; nvSwap_ = false; break; case DRM_FORMAT_NV61: formatFamily_ = NV; horzSubSample_ = 2; vertSubSample_ = 1; nvSwap_ = true; break; case DRM_FORMAT_NV24: formatFamily_ = NV; horzSubSample_ = 1; vertSubSample_ = 1; nvSwap_ = false; break; case DRM_FORMAT_NV42: formatFamily_ = NV; horzSubSample_ = 1; vertSubSample_ = 1; nvSwap_ = true; break; case DRM_FORMAT_RGB888: formatFamily_ = RGB; r_pos_ = 2; g_pos_ = 1; b_pos_ = 0; bpp_ = 3; break; case DRM_FORMAT_BGR888: formatFamily_ = RGB; r_pos_ = 0; g_pos_ = 1; b_pos_ = 2; bpp_ = 3; break; case DRM_FORMAT_BGRA8888: formatFamily_ = RGB; r_pos_ = 1; g_pos_ = 2; b_pos_ = 3; bpp_ = 4; break; case DRM_FORMAT_VYUY: formatFamily_ = YUV; y_pos_ = 1; cb_pos_ = 2; break; case DRM_FORMAT_YVYU: formatFamily_ = YUV; y_pos_ = 0; cb_pos_ = 3; break; case DRM_FORMAT_UYVY: formatFamily_ = YUV; y_pos_ = 1; cb_pos_ = 0; break; case DRM_FORMAT_YUYV: formatFamily_ = YUV; y_pos_ = 0; cb_pos_ = 1; break; case DRM_FORMAT_MJPEG: formatFamily_ = MJPEG; break; default: return -EINVAL; }; format_ = format; width_ = width; height_ = height; return 0; } void FormatConverter::convert(const unsigned char *src, size_t size, QImage *dst) { switch (formatFamily_) { case MJPEG: dst->loadFromData(src, size, "JPEG"); break; case YUV: convertYUV(src, dst->bits()); break; case RGB: convertRGB(src, dst->bits()); break; case NV: convertNV(src, dst->bits()); break; }; } static void yuv_to_rgb(int y, int u, int v, int *r, int *g, int *b) { int c = y - 16; int d = u - 128; int e = v - 128; *r = CLIP(( 298 * c + 409 * e + 128) >> RGBSHIFT); *g = CLIP(( 298 * c - 100 * d - 208 * e + 128) >> RGBSHIFT); *b = CLIP(( 298 * c + 516 * d + 128) >> RGBSHIFT); } void FormatConverter::convertNV(const unsigned char *src, unsigned char *dst) { unsigned int c_stride = width_ * (2 / horzSubSample_); unsigned int c_inc = horzSubSample_ == 1 ? 2 : 0; unsigned int cb_pos = nvSwap_ ? 1 : 0; unsigned int cr_pos = nvSwap_ ? 0 : 1; const unsigned char *src_c = src + width_ * height_; int r, g, b; for (unsigned int y = 0; y < height_; y++) { const unsigned char *src_y = src + y * width_; const unsigned char *src_cb = src_c + (y / vertSubSample_) * c_stride + cb_pos; const unsigned char *src_cr = src_c + (y / vertSubSample_) * c_stride + cr_pos; for (unsigned int x = 0; x < width_; x += 2) { yuv_to_rgb(*src_y, *src_cb, *src_cr, &r, &g, &b); dst[0] = b; dst[1] = g; dst[2] = r; dst[3] = 0xff; src_y++; src_cb += c_inc; src_cr += c_inc; dst += 4; yuv_to_rgb(*src_y, *src_cb, *src_cr, &r, &g, &b); dst[0] = b; dst[1] = g; dst[2] = r; dst[3] = 0xff; src_y++; src_cb += 2; src_cr += 2; dst += 4; } } } void FormatConverter::convertRGB(const unsigned char *src, unsigned char *dst) { unsigned int x, y; int r, g, b; for (y = 0; y < height_; y++) { for (x = 0; x < width_; x++) { r = src[bpp_ * x + r_pos_]; g = src[bpp_ * x + g_pos_]; b = src[bpp_ * x + b_pos_]; dst[4 * x + 0] = b; dst[4 * x + 1] = g; dst[4 * x + 2] = r; dst[4 * x + 3] = 0xff; } src += width_ * bpp_; dst += width_ * 4; } } void FormatConverter::convertYUV(const unsigned char *src, unsigned char *dst) { unsigned int src_x, src_y, dst_x, dst_y; unsigned int src_stride; unsigned int dst_stride; unsigned int cr_pos; int r, g, b, y, cr, cb; cr_pos = (cb_pos_ + 2) % 4; src_stride = width_ * 2; dst_stride = width_ * 4; for (src_y = 0, dst_y = 0; dst_y < height_; src_y++, dst_y++) { for (src_x = 0, dst_x = 0; dst_x < width_; ) { cb = src[src_y * src_stride + src_x * 4 + cb_pos_]; cr = src[src_y * src_stride + src_x * 4 + cr_pos]; y = src[src_y * src_stride + src_x * 4 + y_pos_]; yuv_to_rgb(y, cb, cr, &r, &g, &b); dst[dst_y * dst_stride + 4 * dst_x + 0] = b; dst[dst_y * dst_stride + 4 * dst_x + 1] = g; dst[dst_y * dst_stride + 4 * dst_x + 2] = r; dst[dst_y * dst_stride + 4 * dst_x + 3] = 0xff; dst_x++; y = src[src_y * src_stride + src_x * 4 + y_pos_ + 2]; yuv_to_rgb(y, cb, cr, &r, &g, &b); dst[dst_y * dst_stride + 4 * dst_x + 0] = b; dst[dst_y * dst_stride + 4 * dst_x + 1] = g; dst[dst_y * dst_stride + 4 * dst_x + 2] = r; dst[dst_y * dst_stride + 4 * dst_x + 3] = 0xff; dst_x++; src_x++; } } } amp;id=9361cd1ffa15a14fd808d8e865658d2e88f2ca04'>raspberrypi.cpp
blob: d8232ff8e065579515812a22e65dba52de0f1732 (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

/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2019-2021, Raspberry Pi Ltd
 *
 * raspberrypi.cpp - Pipeline handler for Raspberry Pi devices
 */
#include <algorithm>
#include <assert.h>
#include <cmath>
#include <fcntl.h>
#include <memory>
#include <mutex>
#include <queue>
#include <unordered_set>
#include <utility>

#include <libcamera/base/shared_fd.h>
#include <libcamera/base/utils.h>

#include <libcamera/camera.h>
#include <libcamera/control_ids.h>
#include <libcamera/formats.h>
#include <libcamera/ipa/raspberrypi_ipa_interface.h>
#include <libcamera/ipa/raspberrypi_ipa_proxy.h>
#include <libcamera/logging.h>
#include <libcamera/property_ids.h>
#include <libcamera/request.h>

#include <linux/bcm2835-isp.h>
#include <linux/media-bus-format.h>
#include <linux/videodev2.h>

#include "libcamera/internal/bayer_format.h"
#include "libcamera/internal/camera.h"
#include "libcamera/internal/camera_sensor.h"
#include "libcamera/internal/device_enumerator.h"
#include "libcamera/internal/framebuffer.h"
#include "libcamera/internal/ipa_manager.h"
#include "libcamera/internal/media_device.h"
#include "libcamera/internal/pipeline_handler.h"
#include "libcamera/internal/v4l2_videodevice.h"

#include "delayed_controls.h"
#include "dma_heaps.h"
#include "rpi_stream.h"

using namespace std::chrono_literals;

namespace libcamera {

LOG_DEFINE_CATEGORY(RPI)

namespace {

constexpr unsigned int defaultRawBitDepth = 12;

/* Map of mbus codes to supported sizes reported by the sensor. */
using SensorFormats = std::map<unsigned int, std::vector<Size>>;

SensorFormats populateSensorFormats(std::unique_ptr<CameraSensor> &sensor)
{
	SensorFormats formats;

	for (auto const mbusCode : sensor->mbusCodes())
		formats.emplace(mbusCode, sensor->sizes(mbusCode));

	return formats;
}

bool isMonoSensor(std::unique_ptr<CameraSensor> &sensor)
{
	unsigned int mbusCode = sensor->mbusCodes()[0];
	const BayerFormat &bayer = BayerFormat::fromMbusCode(mbusCode);

	return bayer.order == BayerFormat::Order::MONO;
}

PixelFormat mbusCodeToPixelFormat(unsigned int mbus_code,
				  BayerFormat::Packing packingReq)
{
	BayerFormat bayer = BayerFormat::fromMbusCode(mbus_code);

	ASSERT(bayer.isValid());

	bayer.packing = packingReq;
	PixelFormat pix = bayer.toPixelFormat();

	/*
	 * Not all formats (e.g. 8-bit or 16-bit Bayer formats) can have packed
	 * variants. So if the PixelFormat returns as invalid, use the non-packed
	 * conversion instead.
	 */
	if (!pix.isValid()) {
		bayer.packing = BayerFormat::Packing::None;
		pix = bayer.toPixelFormat();
	}

	return pix;
}

V4L2DeviceFormat toV4L2DeviceFormat(const V4L2VideoDevice *dev,
				    const V4L2SubdeviceFormat &format,
				    BayerFormat::Packing packingReq)
{
	const PixelFormat pix = mbusCodeToPixelFormat(format.mbus_code, packingReq);
	V4L2DeviceFormat deviceFormat;

	deviceFormat.fourcc = dev->toV4L2PixelFormat(pix);
	deviceFormat.size = format.size;
	deviceFormat.colorSpace = format.colorSpace;
	return deviceFormat;
}

bool isRaw(const PixelFormat &pixFmt)
{
	/* This test works for both Bayer and raw mono formats. */
	return BayerFormat::fromPixelFormat(pixFmt).isValid();
}

double scoreFormat(double desired, double actual)
{
	double score = desired - actual;
	/* Smaller desired dimensions are preferred. */
	if (score < 0.0)
		score = (-score) / 8;
	/* Penalise non-exact matches. */
	if (actual != desired)
		score *= 2;

	return score;
}

V4L2SubdeviceFormat findBestFormat(const SensorFormats &formatsMap, const Size &req, unsigned int bitDepth)
{
	double bestScore = std::numeric_limits<double>::max(), score;
	V4L2SubdeviceFormat bestFormat;
	bestFormat.colorSpace = ColorSpace::Raw;

	constexpr float penaltyAr = 1500.0;
	constexpr float penaltyBitDepth = 500.0;

	/* Calculate the closest/best mode from the user requested size. */
	for (const auto &iter : formatsMap) {
		const unsigned int mbusCode = iter.first;
		const PixelFormat format = mbusCodeToPixelFormat(mbusCode,
								 BayerFormat::Packing::None);
		const PixelFormatInfo &info = PixelFormatInfo::info(format);

		for (const Size &size : iter.second) {
			double reqAr = static_cast<double>(req.width) / req.height;
			double fmtAr = static_cast<double>(size.width) / size.height;

			/* Score the dimensions for closeness. */
			score = scoreFormat(req.width, size.width);
			score += scoreFormat(req.height, size.height);
			score += penaltyAr * scoreFormat(reqAr, fmtAr);

			/* Add any penalties... this is not an exact science! */
			score += utils::abs_diff(info.bitsPerPixel, bitDepth) * penaltyBitDepth;

			if (score <= bestScore) {
				bestScore = score;
				bestFormat.mbus_code = mbusCode;
				bestFormat.size = size;
			}

			LOG(RPI, Debug) << "Format: " << size
					<< " fmt " << format
					<< " Score: " << score
					<< " (best " << bestScore << ")";
		}
	}

	return bestFormat;
}

enum class Unicam : unsigned int { Image, Embedded };
enum class Isp : unsigned int { Input, Output0, Output1, Stats };

} /* namespace */

class RPiCameraData : public Camera::Private
{
public:
	RPiCameraData(PipelineHandler *pipe)
		: Camera::Private(pipe), state_(State::Stopped),
		  supportsFlips_(false), flipsAlterBayerOrder_(false),
		  dropFrameCount_(0), buffersAllocated_(false), ispOutputCount_(0)
	{
	}

	~RPiCameraData()
	{
		freeBuffers();
	}

	void freeBuffers();
	void frameStarted(uint32_t sequence);

	int loadIPA(ipa::RPi::IPAInitResult *result);
	int configureIPA(const CameraConfiguration *config, ipa::RPi::IPAConfigResult *result);

	void enumerateVideoDevices(MediaLink *link);

	void statsMetadataComplete(uint32_t bufferId, const ControlList &controls);
	void runIsp(uint32_t bufferId);
	void embeddedComplete(uint32_t bufferId);
	void setIspControls(const ControlList &controls);
	void setDelayedControls(const ControlList &controls, uint32_t delayContext);
	void setSensorControls(ControlList &controls);
	void unicamTimeout();

	/* bufferComplete signal handlers. */
	void unicamBufferDequeue(FrameBuffer *buffer);
	void ispInputDequeue(FrameBuffer *buffer);
	void ispOutputDequeue(FrameBuffer *buffer);

	void clearIncompleteRequests();
	void handleStreamBuffer(FrameBuffer *buffer, RPi::Stream *stream);
	void handleExternalBuffer(FrameBuffer *buffer, RPi::Stream *stream);
	void handleState();
	Rectangle scaleIspCrop(const Rectangle &ispCrop) const;
	void applyScalerCrop(const ControlList &controls);

	std::unique_ptr<ipa::RPi::IPAProxyRPi> ipa_;

	std::unique_ptr<CameraSensor> sensor_;
	SensorFormats sensorFormats_;
	/* Array of Unicam and ISP device streams and associated buffers/streams. */
	RPi::Device<Unicam, 2> unicam_;
	RPi::Device<Isp, 4> isp_;
	/* The vector below is just for convenience when iterating over all streams. */
	std::vector<RPi::Stream *> streams_;
	/* Stores the ids of the buffers mapped in the IPA. */
	std::unordered_set<unsigned int> ipaBuffers_;
	/*
	 * Stores a cascade of Video Mux or Bridge devices between the sensor and
	 * Unicam together with media link across the entities.
	 */
	std::vector<std::pair<std::unique_ptr<V4L2Subdevice>, MediaLink *>> bridgeDevices_;

	/* DMAHEAP allocation helper. */
	RPi::DmaHeap dmaHeap_;
	SharedFD lsTable_;

	std::unique_ptr<RPi::DelayedControls> delayedCtrls_;
	bool sensorMetadata_;

	/*
	 * All the functions in this class are called from a single calling
	 * thread. So, we do not need to have any mutex to protect access to any
	 * of the variables below.
	 */
	enum class State { Stopped, Idle, Busy, IpaComplete, Error };
	State state_;

	bool isRunning()
	{
		return state_ != State::Stopped && state_ != State::Error;
	}

	struct BayerFrame {
		FrameBuffer *buffer;
		ControlList controls;
		unsigned int delayContext;
	};

	std::queue<BayerFrame> bayerQueue_;
	std::queue<FrameBuffer *> embeddedQueue_;
	std::deque<Request *> requestQueue_;

	/*
	 * Manage horizontal and vertical flips supported (or not) by the
	 * sensor. Also store the "native" Bayer order (that is, with no
	 * transforms applied).
	 */
	bool supportsFlips_;
	bool flipsAlterBayerOrder_;
	BayerFormat::Order nativeBayerOrder_;

	/* For handling digital zoom. */
	IPACameraSensorInfo sensorInfo_;
	Rectangle ispCrop_; /* crop in ISP (camera mode) pixels */
	Rectangle scalerCrop_; /* crop in sensor native pixels */
	Size ispMinCropSize_;

	unsigned int dropFrameCount_;

	/*
	 * If set, this stores the value that represets a gain of one for
	 * the V4L2_CID_NOTIFY_GAINS control.
	 */
	std::optional<int32_t> notifyGainsUnity_;

	/* Have internal buffers been allocated? */
	bool buffersAllocated_;

private:
	void checkRequestCompleted();
	void fillRequestMetadata(const ControlList &bufferControls,
				 Request *request);
	void tryRunPipeline();
	bool findMatchingBuffers(BayerFrame &bayerFrame, FrameBuffer *&embeddedBuffer);

	unsigned int ispOutputCount_;
};

class RPiCameraConfiguration : public CameraConfiguration
{
public:
	RPiCameraConfiguration(const RPiCameraData *data);

	Status validate() override;

	/* Cache the combinedTransform_ that will be applied to the sensor */
	Transform combinedTransform_;

private:
	const RPiCameraData *data_;
};

class PipelineHandlerRPi : public PipelineHandler
{
public:
	PipelineHandlerRPi(CameraManager *manager);

	std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera,
		const StreamRoles &roles) override;
	int configure(Camera *camera, CameraConfiguration *config) override;

	int exportFrameBuffers(Camera *camera, Stream *stream,
			       std::vector<std::unique_ptr<FrameBuffer>> *buffers) override;

	int start(Camera *camera, const ControlList *controls) override;
	void stopDevice(Camera *camera) override;

	int queueRequestDevice(Camera *camera, Request *request) override;

	bool match(DeviceEnumerator *enumerator) override;

	void releaseDevice(Camera *camera) override;

private:
	RPiCameraData *cameraData(Camera *camera)
	{
		return static_cast<RPiCameraData *>(camera->_d());
	}

	int registerCamera(MediaDevice *unicam, MediaDevice *isp, MediaEntity *sensorEntity);
	int queueAllBuffers(Camera *camera);
	int prepareBuffers(Camera *camera);
	void mapBuffers(Camera *camera, const RPi::BufferMap &buffers, unsigned int mask);
};

RPiCameraConfiguration::RPiCameraConfiguration(const RPiCameraData *data)
	: CameraConfiguration(), data_(data)
{
}

CameraConfiguration::Status RPiCameraConfiguration::validate()
{
	Status status = Valid;

	if (config_.empty())
		return Invalid;

	status = validateColorSpaces(ColorSpaceFlag::StreamsShareColorSpace);

	/*
	 * Validate the requested transform against the sensor capabilities and
	 * rotation and store the final combined transform that configure() will
	 * need to apply to the sensor to save us working it out again.
	 */
	Transform requestedTransform = transform;
	combinedTransform_ = data_->sensor_->validateTransform(&transform);
	if (transform != requestedTransform)
		status = Adjusted;

	unsigned int rawCount = 0, outCount = 0, count = 0, maxIndex = 0;
	std::pair<int, Size> outSize[2];
	Size maxSize;
	for (StreamConfiguration &cfg : config_) {
		if (isRaw(cfg.pixelFormat)) {
			/*
			 * Calculate the best sensor mode we can use based on
			 * the user request.
			 */
			V4L2VideoDevice *unicam = data_->unicam_[Unicam::Image].dev();
			const PixelFormatInfo &info = PixelFormatInfo::info(cfg.pixelFormat);
			unsigned int bitDepth = info.isValid() ? info.bitsPerPixel : defaultRawBitDepth;
			V4L2SubdeviceFormat sensorFormat = findBestFormat(data_->sensorFormats_, cfg.size, bitDepth);
			BayerFormat::Packing packing = BayerFormat::Packing::CSI2;
			if (info.isValid() && !info.packed)
				packing = BayerFormat::Packing::None;
			V4L2DeviceFormat unicamFormat = toV4L2DeviceFormat(unicam, sensorFormat, packing);
			int ret = unicam->tryFormat(&unicamFormat);
			if (ret)
				return Invalid;

			/*
			 * Some sensors change their Bayer order when they are
			 * h-flipped or v-flipped, according to the transform.
			 * If this one does, we must advertise the transformed
			 * Bayer order in the raw stream. Note how we must
			 * fetch the "native" (i.e. untransformed) Bayer order,
			 * because the sensor may currently be flipped!
			 */
			V4L2PixelFormat fourcc = unicamFormat.fourcc;
			if (data_->flipsAlterBayerOrder_) {
				BayerFormat bayer = BayerFormat::fromV4L2PixelFormat(fourcc);
				bayer.order = data_->nativeBayerOrder_;
				bayer = bayer.transform(combinedTransform_);
				fourcc = bayer.toV4L2PixelFormat();
			}

			PixelFormat unicamPixFormat = fourcc.toPixelFormat();
			if (cfg.size != unicamFormat.size ||
			    cfg.pixelFormat != unicamPixFormat) {
				cfg.size = unicamFormat.size;
				cfg.pixelFormat = unicamPixFormat;
				status = Adjusted;
			}

			cfg.stride = unicamFormat.planes[0].bpl;
			cfg.frameSize = unicamFormat.planes[0].size;

			rawCount++;
		} else {
			outSize[outCount] = std::make_pair(count, cfg.size);
			/* Record the largest resolution for fixups later. */
			if (maxSize < cfg.size) {
				maxSize = cfg.size;
				maxIndex = outCount;
			}
			outCount++;
		}

		count++;

		/* Can only output 1 RAW stream, or 2 YUV/RGB streams. */
		if (rawCount > 1 || outCount > 2) {
			LOG(RPI, Error) << "Invalid number of streams requested";
			return Invalid;
		}
	}

	/*
	 * Now do any fixups needed. For the two ISP outputs, one stream must be
	 * equal or smaller than the other in all dimensions.
	 */
	for (unsigned int i = 0; i < outCount; i++) {
		outSize[i].second.width = std::min(outSize[i].second.width,
						   maxSize.width);
		outSize[i].second.height = std::min(outSize[i].second.height,
						    maxSize.height);

		if (config_.at(outSize[i].first).size != outSize[i].second) {
			config_.at(outSize[i].first).size = outSize[i].second;
			status = Adjusted;
		}

		/*
		 * Also validate the correct pixel formats here.
		 * Note that Output0 and Output1 support a different
		 * set of formats.
		 *
		 * Output 0 must be for the largest resolution. We will
		 * have that fixed up in the code above.
		 *
		 */
		StreamConfiguration &cfg = config_.at(outSize[i].first);
		PixelFormat &cfgPixFmt = cfg.pixelFormat;
		V4L2VideoDevice *dev;

		if (i == maxIndex)
			dev = data_->isp_[Isp::Output0].dev();
		else
			dev = data_->isp_[Isp::Output1].dev();

		V4L2VideoDevice::Formats fmts = dev->formats();

		if (fmts.find(dev->toV4L2PixelFormat(cfgPixFmt)) == fmts.end()) {
			/* If we cannot find a native format, use a default one. */
			cfgPixFmt = formats::NV12;
			status = Adjusted;
		}

		V4L2DeviceFormat format;
		format.fourcc = dev->toV4L2PixelFormat(cfg.pixelFormat);
		format.size = cfg.size;
		format.colorSpace = cfg.colorSpace;

		LOG(RPI, Debug)
			<< "Try color space " << ColorSpace::toString(cfg.colorSpace);

		int ret = dev->tryFormat(&format);
		if (ret)
			return Invalid;

		if (cfg.colorSpace != format.colorSpace) {
			status = Adjusted;
			LOG(RPI, Debug)
				<< "Color space changed from "
				<< ColorSpace::toString(cfg.colorSpace) << " to "
				<< ColorSpace::toString(format.colorSpace);
		}

		cfg.colorSpace = format.colorSpace;

		cfg.stride = format.planes[0].bpl;
		cfg.frameSize = format.planes[0].size;

	}

	return status;
}

PipelineHandlerRPi::PipelineHandlerRPi(CameraManager *manager)
	: PipelineHandler(manager)
{
}

std::unique_ptr<CameraConfiguration>
PipelineHandlerRPi::generateConfiguration(Camera *camera, const StreamRoles &roles)
{
	RPiCameraData *data = cameraData(camera);
	std::unique_ptr<CameraConfiguration> config =
		std::make_unique<RPiCameraConfiguration>(data);
	V4L2SubdeviceFormat sensorFormat;
	unsigned int bufferCount;
	PixelFormat pixelFormat;
	V4L2VideoDevice::Formats fmts;
	Size size;
	std::optional<ColorSpace> colorSpace;

	if (roles.empty())
		return config;

	unsigned int rawCount = 0;
	unsigned int outCount = 0;
	Size sensorSize = data->sensor_->resolution();
	for (const StreamRole role : roles) {
		switch (role) {
		case StreamRole::Raw:
			size = sensorSize;
			sensorFormat = findBestFormat(data->sensorFormats_, size, defaultRawBitDepth);
			pixelFormat = mbusCodeToPixelFormat(sensorFormat.mbus_code,
							    BayerFormat::Packing::CSI2);
			ASSERT(pixelFormat.isValid());
			colorSpace = ColorSpace::Raw;
			bufferCount = 2;
			rawCount++;
			break;

		case StreamRole::StillCapture:
			fmts = data->isp_[Isp::Output0].dev()->formats();
			pixelFormat = formats::NV12;
			/*
			 * Still image codecs usually expect the sYCC color space.
			 * Even RGB codecs will be fine as the RGB we get with the
			 * sYCC color space is the same as sRGB.
			 */
			colorSpace = ColorSpace::Sycc;
			/* Return the largest sensor resolution. */
			size = sensorSize;
			bufferCount = 1;
			outCount++;
			break;

		case StreamRole::VideoRecording:
			/*
			 * The colour denoise algorithm requires the analysis
			 * image, produced by the second ISP output, to be in
			 * YUV420 format. Select this format as the default, to
			 * maximize chances that it will be picked by
			 * applications and enable usage of the colour denoise
			 * algorithm.
			 */
			fmts = data->isp_[Isp::Output0].dev()->formats();
			pixelFormat = formats::YUV420;
			/*
			 * Choose a color space appropriate for video recording.
			 * Rec.709 will be a good default for HD resolutions.
			 */
			colorSpace = ColorSpace::Rec709;
			size = { 1920, 1080 };
			bufferCount = 4;
			outCount++;
			break;

		case StreamRole::Viewfinder:
			fmts = data->isp_[Isp::Output0].dev()->formats();
			pixelFormat = formats::ARGB8888;
			colorSpace = ColorSpace::Sycc;
			size = { 800, 600 };
			bufferCount = 4;
			outCount++;
			break;

		default:
			LOG(RPI, Error) << "Requested stream role not supported: "
					<< role;
			return nullptr;
		}

		if (rawCount > 1 || outCount > 2) {
			LOG(RPI, Error) << "Invalid stream roles requested";
			return nullptr;
		}

		std::map<PixelFormat, std::vector<SizeRange>> deviceFormats;
		if (role == StreamRole::Raw) {
			/* Translate the MBUS codes to a PixelFormat. */
			for (const auto &format : data->sensorFormats_) {
				PixelFormat pf = mbusCodeToPixelFormat(format.first,
								       BayerFormat::Packing::CSI2);
				if (pf.isValid())
					deviceFormats.emplace(std::piecewise_construct,	std::forward_as_tuple(pf),
						std::forward_as_tuple(format.second.begin(), format.second.end()));
			}
		} else {
			/*
			 * Translate the V4L2PixelFormat to PixelFormat. Note that we
			 * limit the recommended largest ISP output size to match the
			 * sensor resolution.
			 */
			for (const auto &format : fmts) {
				PixelFormat pf = format.first.toPixelFormat();
				if (pf.isValid()) {
					const SizeRange &ispSizes = format.second[0];
					deviceFormats[pf].emplace_back(ispSizes.min, sensorSize,
								       ispSizes.hStep, ispSizes.vStep);
				}
			}
		}

		/* Add the stream format based on the device node used for the use case. */
		StreamFormats formats(deviceFormats);
		StreamConfiguration cfg(formats);
		cfg.size = size;
		cfg.pixelFormat = pixelFormat;
		cfg.colorSpace = colorSpace;
		cfg.bufferCount = bufferCount;
		config->addConfiguration(cfg);
	}

	config->validate();

	return config;
}

int PipelineHandlerRPi::configure(Camera *camera, CameraConfiguration *config)
{
	RPiCameraData *data = cameraData(camera);
	int ret;

	/* Start by freeing all buffers and reset the Unicam and ISP stream states. */
	data->freeBuffers();
	for (auto const stream : data->streams_)
		stream->setExternal(false);

	BayerFormat::Packing packing = BayerFormat::Packing::CSI2;
	Size maxSize, sensorSize;
	unsigned int maxIndex = 0;
	bool rawStream = false;
	unsigned int bitDepth = defaultRawBitDepth;

	/*
	 * Look for the RAW stream (if given) size as well as the largest
	 * ISP output size.
	 */
	for (unsigned i = 0; i < config->size(); i++) {
		StreamConfiguration &cfg = config->at(i);

		if (isRaw(cfg.pixelFormat)) {
			/*
			 * If we have been given a RAW stream, use that size
			 * for setting up the sensor.
			 */
			sensorSize = cfg.size;
			rawStream = true;
			/* Check if the user has explicitly set an unpacked format. */
			BayerFormat bayerFormat = BayerFormat::fromPixelFormat(cfg.pixelFormat);
			packing = bayerFormat.packing;
			bitDepth = bayerFormat.bitDepth;
		} else {
			if (cfg.size > maxSize) {
				maxSize = config->at(i).size;
				maxIndex = i;
			}
		}
	}

	/* First calculate the best sensor mode we can use based on the user request. */
	V4L2SubdeviceFormat sensorFormat = findBestFormat(data->sensorFormats_, rawStream ? sensorSize : maxSize, bitDepth);
	/* Apply any cached transform. */
	const RPiCameraConfiguration *rpiConfig = static_cast<const RPiCameraConfiguration *>(config);
	sensorFormat.transform = rpiConfig->combinedTransform_;
	/* Finally apply the format on the sensor. */
	ret = data->sensor_->setFormat(&sensorFormat);
	if (ret)
		return ret;

	V4L2VideoDevice *unicam = data->unicam_[Unicam::Image].dev();
	V4L2DeviceFormat unicamFormat = toV4L2DeviceFormat(unicam, sensorFormat, packing);
	ret = unicam->setFormat(&unicamFormat);
	if (ret)
		return ret;

	LOG(RPI, Info) << "Sensor: " << camera->id()
		       << " - Selected sensor format: " << sensorFormat
		       << " - Selected unicam format: " << unicamFormat;

	ret = data->isp_[Isp::Input].dev()->setFormat(&unicamFormat);
	if (ret)
		return ret;

	/*
	 * See which streams are requested, and route the user
	 * StreamConfiguration appropriately.
	 */
	V4L2DeviceFormat format;
	bool output0Set = false, output1Set = false;
	for (unsigned i = 0; i < config->size(); i++) {
		StreamConfiguration &cfg = config->at(i);

		if (isRaw(cfg.pixelFormat)) {
			cfg.setStream(&data->unicam_[Unicam::Image]);
			data->unicam_[Unicam::Image].setExternal(true);
			continue;
		}

		/* The largest resolution gets routed to the ISP Output 0 node. */
		RPi::Stream *stream = i == maxIndex ? &data->isp_[Isp::Output0]
						    : &data->isp_[Isp::Output1];

		V4L2PixelFormat fourcc = stream->dev()->toV4L2PixelFormat(cfg.pixelFormat);
		format.size = cfg.size;
		format.fourcc = fourcc;
		format.colorSpace = cfg.colorSpace;

		LOG(RPI, Debug) << "Setting " << stream->name() << " to "
				<< format;

		ret = stream->dev()->setFormat(&format);
		if (ret)
			return -EINVAL;

		if (format.size != cfg.size || format.fourcc != fourcc) {
			LOG(RPI, Error)
				<< "Failed to set requested format on " << stream->name()
				<< ", returned " << format;
			return -EINVAL;
		}

		LOG(RPI, Debug)
			<< "Stream " << stream->name() << " has color space "
			<< ColorSpace::toString(cfg.colorSpace);

		cfg.setStream(stream);
		stream->setExternal(true);

		if (i != maxIndex)
			output1Set = true;
		else
			output0Set = true;
	}

	/*
	 * If ISP::Output0 stream has not been configured by the application,
	 * we must allow the hardware to generate an output so that the data
	 * flow in the pipeline handler remains consistent, and we still generate
	 * statistics for the IPA to use. So enable the output at a very low
	 * resolution for internal use.
	 *
	 * \todo Allow the pipeline to work correctly without Output0 and only
	 * statistics coming from the hardware.
	 */
	if (!output0Set) {
		V4L2VideoDevice *dev = data->isp_[Isp::Output0].dev();

		maxSize = Size(320, 240);
		format = {};
		format.size = maxSize;
		format.fourcc = dev->toV4L2PixelFormat(formats::YUV420);
		/* No one asked for output, so the color space doesn't matter. */
		format.colorSpace = ColorSpace::Sycc;
		ret = dev->setFormat(&format);
		if (ret) {
			LOG(RPI, Error)
				<< "Failed to set default format on ISP Output0: "
				<< ret;
			return -EINVAL;
		}

		LOG(RPI, Debug) << "Defaulting ISP Output0 format to "
				<< format;
	}

	/*
	 * If ISP::Output1 stream has not been requested by the application, we
	 * set it up for internal use now. This second stream will be used for
	 * fast colour denoise, and must be a quarter resolution of the ISP::Output0
	 * stream. However, also limit the maximum size to 1200 pixels in the
	 * larger dimension, just to avoid being wasteful with buffer allocations
	 * and memory bandwidth.
	 *
	 * \todo If Output 1 format is not YUV420, Output 1 ought to be disabled as
	 * colour denoise will not run.
	 */
	if (!output1Set) {
		V4L2VideoDevice *dev = data->isp_[Isp::Output1].dev();

		V4L2DeviceFormat output1Format;
		constexpr Size maxDimensions(1200, 1200);
		const Size limit = maxDimensions.boundedToAspectRatio(format.size);

		output1Format.size = (format.size / 2).boundedTo(limit).alignedDownTo(2, 2);
		output1Format.colorSpace = format.colorSpace;
		output1Format.fourcc = dev->toV4L2PixelFormat(formats::YUV420);

		LOG(RPI, Debug) << "Setting ISP Output1 (internal) to "
				<< output1Format;

		ret = dev->setFormat(&output1Format);
		if (ret) {
			LOG(RPI, Error) << "Failed to set format on ISP Output1: "
					<< ret;
			return -EINVAL;
		}
	}

	/* ISP statistics output format. */
	format = {};
	format.fourcc = V4L2PixelFormat(V4L2_META_FMT_BCM2835_ISP_STATS);
	ret = data->isp_[Isp::Stats].dev()->setFormat(&format);
	if (ret) {
		LOG(RPI, Error) << "Failed to set format on ISP stats stream: "
				<< format;
		return ret;
	}

	/* Figure out the smallest selection the ISP will allow. */
	Rectangle testCrop(0, 0, 1, 1);
	data->isp_[Isp::Input].dev()->setSelection(V4L2_SEL_TGT_CROP, &testCrop);
	data->ispMinCropSize_ = testCrop.size();

	/* Adjust aspect ratio by providing crops on the input image. */
	Size size = unicamFormat.size.boundedToAspectRatio(maxSize);
	Rectangle crop = size.centeredTo(Rectangle(unicamFormat.size).center());
	data->ispCrop_ = crop;

	data->isp_[Isp::Input].dev()->setSelection(V4L2_SEL_TGT_CROP, &crop);

	ipa::RPi::IPAConfigResult result;
	ret = data->configureIPA(config, &result);
	if (ret)
		LOG(RPI, Error) << "Failed to configure the IPA: " << ret;

	/*
	 * Set the scaler crop to the value we are using (scaled to native sensor
	 * coordinates).
	 */
	data->scalerCrop_ = data->scaleIspCrop(data->ispCrop_);

	/*
	 * Configure the Unicam embedded data output format only if the sensor
	 * supports it.
	 */
	if (data->sensorMetadata_) {
		V4L2SubdeviceFormat embeddedFormat;

		data->sensor_->device()->getFormat(1, &embeddedFormat);
		format.fourcc = V4L2PixelFormat(V4L2_META_FMT_SENSOR_DATA);
		format.planes[0].size = embeddedFormat.size.width * embeddedFormat.size.height;

		LOG(RPI, Debug) << "Setting embedded data format.";
		ret = data->unicam_[Unicam::Embedded].dev()->setFormat(&format);
		if (ret) {
			LOG(RPI, Error) << "Failed to set format on Unicam embedded: "
					<< format;
			return ret;
		}
	}

	/*
	 * Update the ScalerCropMaximum to the correct value for this camera mode.
	 * For us, it's the same as the "analogue crop".
	 *
	 * \todo Make this property the ScalerCrop maximum value when dynamic
	 * controls are available and set it at validate() time
	 */
	data->properties_.set(properties::ScalerCropMaximum, data->sensorInfo_.analogCrop);

	/* Store the mode sensitivity for the application. */
	data->properties_.set(properties::SensorSensitivity, result.modeSensitivity);

	/* Update the controls that the Raspberry Pi IPA can handle. */
	ControlInfoMap::Map ctrlMap;
	for (auto const &c : result.controlInfo)
		ctrlMap.emplace(c.first, c.second);

	/* Add the ScalerCrop control limits based on the current mode. */
	Rectangle ispMinCrop(data->ispMinCropSize_);
	ispMinCrop.scaleBy(data->sensorInfo_.analogCrop.size(), data->sensorInfo_.outputSize);
	ctrlMap[&controls::ScalerCrop] = ControlInfo(ispMinCrop, Rectangle(data->sensorInfo_.analogCrop.size()));

	data->controlInfo_ = ControlInfoMap(std::move(ctrlMap), result.controlInfo.idmap());

	/* Setup the Video Mux/Bridge entities. */
	for (auto &[device, link] : data->bridgeDevices_) {
		/*
		 * Start by disabling all the sink pad links on the devices in the
		 * cascade, with the exception of the link connecting the device.
		 */
		for (const MediaPad *p : device->entity()->pads()) {
			if (!(p->flags() & MEDIA_PAD_FL_SINK))
				continue;

			for (MediaLink *l : p->links()) {
				if (l != link)
					l->setEnabled(false);
			}
		}

		/*
		 * Next, enable the entity -> entity links, and setup the pad format.
		 *
		 * \todo Some bridge devices may chainge the media bus code, so we
		 * ought to read the source pad format and propagate it to the sink pad.
		 */
		link->setEnabled(true);
		const MediaPad *sinkPad = link->sink();
		ret = device->setFormat(sinkPad->index(), &sensorFormat);
		if (ret) {
			LOG(RPI, Error) << "Failed to set format on " << device->entity()->name()
					<< " pad " << sinkPad->index()
					<< " with format  " << format
					<< ": " << ret;
			return ret;
		}

		LOG(RPI, Debug) << "Configured media link on device " << device->entity()->name()
				<< " on pad " << sinkPad->index();
	}

	return ret;
}

int PipelineHandlerRPi::exportFrameBuffers([[maybe_unused]] Camera *camera, Stream *stream,
					   std::vector<std::unique_ptr<FrameBuffer>> *buffers)
{
	RPi::Stream *s = static_cast<RPi::Stream *>(stream);
	unsigned int count = stream->configuration().bufferCount;
	int ret = s->dev()->exportBuffers(count, buffers);

	s->setExportedBuffers(buffers);

	return ret;
}

int PipelineHandlerRPi::start(Camera *camera, const ControlList *controls)
{
	RPiCameraData *data = cameraData(camera);
	int ret;

	for (auto const stream : data->streams_)
		stream->resetBuffers();

	if (!data->buffersAllocated_) {
		/* Allocate buffers for internal pipeline usage. */
		ret = prepareBuffers(camera);
		if (ret) {
			LOG(RPI, Error) << "Failed to allocate buffers";
			data->freeBuffers();
			stop(camera);
			return ret;
		}
		data->buffersAllocated_ = true;
	}

	/* Check if a ScalerCrop control was specified. */
	if (controls)
		data->applyScalerCrop(*controls);

	/* Start the IPA. */
	ipa::RPi::StartConfig startConfig;
	data->ipa_->start(controls ? *controls : ControlList{ controls::controls },
			  &startConfig);

	/* Apply any gain/exposure settings that the IPA may have passed back. */
	if (!startConfig.controls.empty())
		data->setSensorControls(startConfig.controls);

	/* Configure the number of dropped frames required on startup. */
	data->dropFrameCount_ = startConfig.dropFrameCount;

	/* We need to set the dropFrameCount_ before queueing buffers. */
	ret = queueAllBuffers(camera);
	if (ret) {
		LOG(RPI, Error) << "Failed to queue buffers";
		stop(camera);
		return ret;
	}

	/* Enable SOF event generation. */
	data->unicam_[Unicam::Image].dev()->setFrameStartEnabled(true);

	/*
	 * Reset the delayed controls with the gain and exposure values set by
	 * the IPA.
	 */
	data->delayedCtrls_->reset(0);

	data->state_ = RPiCameraData::State::Idle;

	/* Start all streams. */
	for (auto const stream : data->streams_) {
		ret = stream->dev()->streamOn();
		if (ret) {
			stop(camera);
			return ret;
		}
	}

	/*
	 * Set the dequeue timeout to the larger of 2x the maximum possible
	 * frame duration or 1 second.
	 */
	utils::Duration timeout =
		std::max<utils::Duration>(1s, 2 * startConfig.maxSensorFrameLengthMs * 1ms);
	data->unicam_[Unicam::Image].dev()->setDequeueTimeout(timeout);

	return 0;
}

void PipelineHandlerRPi::stopDevice(Camera *camera)
{
	RPiCameraData *data = cameraData(camera);

	data->state_ = RPiCameraData::State::Stopped;

	/* Disable SOF event generation. */
	data->unicam_[Unicam::Image].dev()->setFrameStartEnabled(false);

	for (auto const stream : data->streams_)
		stream->dev()->streamOff();

	data->clearIncompleteRequests();
	data->bayerQueue_ = {};
	data->embeddedQueue_ = {};

	/* Stop the IPA. */
	data->ipa_->stop();
}

int PipelineHandlerRPi::queueRequestDevice(Camera *camera, Request *request)
{
	RPiCameraData *data = cameraData(camera);

	if (!data->isRunning())
		return -EINVAL;

	LOG(RPI, Debug) << "queueRequestDevice: New request.";

	/* Push all buffers supplied in the Request to the respective streams. */
	for (auto stream : data->streams_) {
		if (!stream->isExternal())
			continue;

		FrameBuffer *buffer = request->findBuffer(stream);
		if (buffer && stream->getBufferId(buffer) == -1) {
			/*
			 * This buffer is not recognised, so it must have been allocated
			 * outside the v4l2 device. Store it in the stream buffer list
			 * so we can track it.
			 */
			stream->setExternalBuffer(buffer);
		}
		/*
		 * If no buffer is provided by the request for this stream, we
		 * queue a nullptr to the stream to signify that it must use an
		 * internally allocated buffer for this capture request. This
		 * buffer will not be given back to the application, but is used
		 * to support the internal pipeline flow.
		 *
		 * The below queueBuffer() call will do nothing if there are not
		 * enough internal buffers allocated, but this will be handled by
		 * queuing the request for buffers in the RPiStream object.
		 */
		int ret = stream->queueBuffer(buffer);
		if (ret)
			return ret;
	}

	/* Push the request to the back of the queue. */
	data->requestQueue_.push_back(request);
	data->handleState();

	return 0;
}

bool PipelineHandlerRPi::match(DeviceEnumerator *enumerator)
{
	DeviceMatch unicam("unicam");
	MediaDevice *unicamDevice = acquireMediaDevice(enumerator, unicam);

	if (!unicamDevice) {
		LOG(RPI, Debug) << "Unable to acquire a Unicam instance";
		return false;
	}

	DeviceMatch isp("bcm2835-isp");
	MediaDevice *ispDevice = acquireMediaDevice(enumerator, isp);

	if (!ispDevice) {
		LOG(RPI, Debug) << "Unable to acquire ISP instance";
		return false;
	}

	/*
	 * The loop below is used to register multiple cameras behind one or more
	 * video mux devices that are attached to a particular Unicam instance.
	 * Obviously these cameras cannot be used simultaneously.
	 */
	unsigned int numCameras = 0;
	for (MediaEntity *entity : unicamDevice->entities()) {
		if (entity->function() != MEDIA_ENT_F_CAM_SENSOR)
			continue;

		int ret = registerCamera(unicamDevice, ispDevice, entity);
		if (ret)
			LOG(RPI, Error) << "Failed to register camera "
					<< entity->name() << ": " << ret;
		else
			numCameras++;
	}

	return !!numCameras;
}

void PipelineHandlerRPi::releaseDevice(Camera *camera)
{
	RPiCameraData *data = cameraData(camera);
	data->freeBuffers();
}

int PipelineHandlerRPi::registerCamera(MediaDevice *unicam, MediaDevice *isp, MediaEntity *sensorEntity)
{
	std::unique_ptr<RPiCameraData> data = std::make_unique<RPiCameraData>(this);

	if (!data->dmaHeap_.isValid())
		return -ENOMEM;

	MediaEntity *unicamImage = unicam->getEntityByName("unicam-image");
	MediaEntity *ispOutput0 = isp->getEntityByName("bcm2835-isp0-output0");
	MediaEntity *ispCapture1 = isp->getEntityByName("bcm2835-isp0-capture1");
	MediaEntity *ispCapture2 = isp->getEntityByName("bcm2835-isp0-capture2");
	MediaEntity *ispCapture3 = isp->getEntityByName("bcm2835-isp0-capture3");

	if (!unicamImage || !ispOutput0 || !ispCapture1 || !ispCapture2 || !ispCapture3)
		return -ENOENT;

	/* Locate and open the unicam video streams. */
	data->unicam_[Unicam::Image] = RPi::Stream("Unicam Image", unicamImage);

	/* An embedded data node will not be present if the sensor does not support it. */
	MediaEntity *unicamEmbedded = unicam->getEntityByName("unicam-embedded");
	if (unicamEmbedded) {
		data->unicam_[Unicam::Embedded] = RPi::Stream("Unicam Embedded", unicamEmbedded);
		data->unicam_[Unicam::Embedded].dev()->bufferReady.connect(data.get(),
									   &RPiCameraData::unicamBufferDequeue);
	}

	/* Tag the ISP input stream as an import stream. */
	data->isp_[Isp::Input] = RPi::Stream("ISP Input", ispOutput0, true);
	data->isp_[Isp::Output0] = RPi::Stream("ISP Output0", ispCapture1);
	data->isp_[Isp::Output1] = RPi::Stream("ISP Output1", ispCapture2);
	data->isp_[Isp::Stats] = RPi::Stream("ISP Stats", ispCapture3);

	/* Wire up all the buffer connections. */
	data->unicam_[Unicam::Image].dev()->dequeueTimeout.connect(data.get(), &RPiCameraData::unicamTimeout);
	data->unicam_[Unicam::Image].dev()->frameStart.connect(data.get(), &RPiCameraData::frameStarted);
	data->unicam_[Unicam::Image].dev()->bufferReady.connect(data.get(), &RPiCameraData::unicamBufferDequeue);
	data->isp_[Isp::Input].dev()->bufferReady.connect(data.get(), &RPiCameraData::ispInputDequeue);
	data->isp_[Isp::Output0].dev()->bufferReady.connect(data.get(), &RPiCameraData::ispOutputDequeue);
	data->isp_[Isp::Output1].dev()->bufferReady.connect(data.get(), &RPiCameraData::ispOutputDequeue);
	data->isp_[Isp::Stats].dev()->bufferReady.connect(data.get(), &RPiCameraData::ispOutputDequeue);

	data->sensor_ = std::make_unique<CameraSensor>(sensorEntity);
	if (!data->sensor_)
		return -EINVAL;

	if (data->sensor_->init())
		return -EINVAL;

	/*
	 * Enumerate all the Video Mux/Bridge devices across the sensor -> unicam
	 * chain. There may be a cascade of devices in this chain!
	 */
	MediaLink *link = sensorEntity->getPadByIndex(0)->links()[0];
	data->enumerateVideoDevices(link);

	data->sensorFormats_ = populateSensorFormats(data->sensor_);

	ipa::RPi::IPAInitResult result;
	if (data->loadIPA(&result)) {
		LOG(RPI, Error) << "Failed to load a suitable IPA library";
		return -EINVAL;
	}

	if (result.sensorConfig.sensorMetadata ^ !!unicamEmbedded) {
		LOG(RPI, Warning) << "Mismatch between Unicam and CamHelper for embedded data usage!";
		result.sensorConfig.sensorMetadata = false;
		if (unicamEmbedded)
			data->unicam_[Unicam::Embedded].dev()->bufferReady.disconnect();
	}

	/*
	 * Open all Unicam and ISP streams. The exception is the embedded data
	 * stream, which only gets opened below if the IPA reports that the sensor
	 * supports embedded data.
	 *
	 * The below grouping is just for convenience so that we can easily
	 * iterate over all streams in one go.
	 */
	data->streams_.push_back(&data->unicam_[Unicam::Image]);
	if (result.sensorConfig.sensorMetadata)
		data->streams_.push_back(&data->unicam_[Unicam::Embedded]);

	for (auto &stream : data->isp_)
		data->streams_.push_back(&stream);

	for (auto stream : data->streams_) {
		int ret = stream->dev()->open();
		if (ret)
			return ret;
	}

	if (!data->unicam_[Unicam::Image].dev()->caps().hasMediaController()) {
		LOG(RPI, Error) << "Unicam driver does not use the MediaController, please update your kernel!";
		return -EINVAL;
	}

	/*
	 * Setup our delayed control writer with the sensor default
	 * gain and exposure delays. Mark VBLANK for priority write.
	 */
	std::unordered_map<uint32_t, RPi::DelayedControls::ControlParams> params = {
		{ V4L2_CID_ANALOGUE_GAIN, { result.sensorConfig.gainDelay, false } },
		{ V4L2_CID_EXPOSURE, { result.sensorConfig.exposureDelay, false } },
		{ V4L2_CID_HBLANK, { result.sensorConfig.hblankDelay, false } },
		{ V4L2_CID_VBLANK, { result.sensorConfig.vblankDelay, true } }
	};
	data->delayedCtrls_ = std::make_unique<RPi::DelayedControls>(data->sensor_->device(), params);
	data->sensorMetadata_ = result.sensorConfig.sensorMetadata;

	/* Register initial controls that the Raspberry Pi IPA can handle. */
	data->controlInfo_ = std::move(result.controlInfo);

	/* Initialize the camera properties. */
	data->properties_ = data->sensor_->properties();

	/*
	 * The V4L2_CID_NOTIFY_GAINS control, if present, is used to inform the
	 * sensor of the colour gains. It is defined to be a linear gain where
	 * the default value represents a gain of exactly one.
	 */
	auto it = data->sensor_->controls().find(V4L2_CID_NOTIFY_GAINS);
	if (it != data->sensor_->controls().end())
		data->notifyGainsUnity_ = it->second.def().get<int32_t>();

	/*
	 * Set a default value for the ScalerCropMaximum property to show
	 * that we support its use, however, initialise it to zero because
	 * it's not meaningful until a camera mode has been chosen.
	 */
	data->properties_.set(properties::ScalerCropMaximum, Rectangle{});

	/*
	 * We cache three things about the sensor in relation to transforms
	 * (meaning horizontal and vertical flips).
	 *
	 * If flips are supported verify if they affect the Bayer ordering
	 * and what the "native" Bayer order is, when no transforms are
	 * applied.
	 *
	 * We note that the sensor's cached list of supported formats is
	 * already in the "native" order, with any flips having been undone.
	 */
	const V4L2Subdevice *sensor = data->sensor_->device();
	const struct v4l2_query_ext_ctrl *hflipCtrl = sensor->controlInfo(V4L2_CID_HFLIP);
	if (hflipCtrl) {
		/* We assume it will support vflips too... */
		data->supportsFlips_ = true;
		data->flipsAlterBayerOrder_ = hflipCtrl->flags & V4L2_CTRL_FLAG_MODIFY_LAYOUT;
	}

	/* Look for a valid Bayer format. */
	BayerFormat bayerFormat;
	for (const auto &iter : data->sensorFormats_) {
		bayerFormat = BayerFormat::fromMbusCode(iter.first);
		if (bayerFormat.isValid())
			break;
	}

	if (!bayerFormat.isValid()) {
		LOG(RPI, Error) << "No Bayer format found";
		return -EINVAL;
	}
	data->nativeBayerOrder_ = bayerFormat.order;

	/*
	 * List the available streams an application may request. At present, we
	 * do not advertise Unicam Embedded and ISP Statistics streams, as there
	 * is no mechanism for the application to request non-image buffer formats.
	 */
	std::set<Stream *> streams;
	streams.insert(&data->unicam_[Unicam::Image]);
	streams.insert(&data->isp_[Isp::Output0]);
	streams.insert(&data->isp_[Isp::Output1]);

	/* Create and register the camera. */
	const std::string &id = data->sensor_->id();
	std::shared_ptr<Camera> camera =
		Camera::create(std::move(data), id, streams);
	PipelineHandler::registerCamera(std::move(camera));

	LOG(RPI, Info) << "Registered camera " << id
		       << " to Unicam device " << unicam->deviceNode()
		       << " and ISP device " << isp->deviceNode();
	return 0;
}

int PipelineHandlerRPi::queueAllBuffers(Camera *camera)
{
	RPiCameraData *data = cameraData(camera);
	int ret;

	for (auto const stream : data->streams_) {
		if (!stream->isExternal()) {
			ret = stream->queueAllBuffers();
			if (ret < 0)
				return ret;
		} else {
			/*
			 * For external streams, we must queue up a set of internal
			 * buffers to handle the number of drop frames requested by
			 * the IPA. This is done by passing nullptr in queueBuffer().
			 *
			 * The below queueBuffer() call will do nothing if there
			 * are not enough internal buffers allocated, but this will
			 * be handled by queuing the request for buffers in the
			 * RPiStream object.
			 */
			unsigned int i;
			for (i = 0; i < data->dropFrameCount_; i++) {
				ret = stream->queueBuffer(nullptr);
				if (ret)
					return ret;
			}
		}
	}

	return 0;
}

int PipelineHandlerRPi::prepareBuffers(Camera *camera)
{
	RPiCameraData *data = cameraData(camera);
	unsigned int numRawBuffers = 0;
	int ret;

	for (Stream *s : camera->streams()) {
		if (isRaw(s->configuration().pixelFormat)) {
			numRawBuffers = s->configuration().bufferCount;
			break;
		}
	}

	/* Decide how many internal buffers to allocate. */
	for (auto const stream : data->streams_) {
		unsigned int numBuffers;
		/*
		 * For Unicam, allocate a minimum of 4 buffers as we want
		 * to avoid any frame drops.
		 */
		constexpr unsigned int minBuffers = 4;
		if (stream == &data->unicam_[Unicam::Image]) {
			/*
			 * If an application has configured a RAW stream, allocate
			 * additional buffers to make up the minimum, but ensure
			 * we have at least 2 sets of internal buffers to use to
			 * minimise frame drops.
			 */
			numBuffers = std::max<int>(2, minBuffers - numRawBuffers);
		} else if (stream == &data->isp_[Isp::Input]) {
			/*
			 * ISP input buffers are imported from Unicam, so follow
			 * similar logic as above to count all the RAW buffers
			 * available.
			 */
			numBuffers = numRawBuffers + std::max<int>(2, minBuffers - numRawBuffers);

		} else if (stream == &data->unicam_[Unicam::Embedded]) {
			/*
			 * Embedded data buffers are (currently) for internal use,
			 * so allocate the minimum required to avoid frame drops.
			 */
			numBuffers = minBuffers;
		} else {
			/*
			 * Since the ISP runs synchronous with the IPA and requests,
			 * we only ever need one set of internal buffers. Any buffers
			 * the application wants to hold onto will already be exported
			 * through PipelineHandlerRPi::exportFrameBuffers().
			 */
			numBuffers = 1;
		}

		ret = stream->prepareBuffers(numBuffers);
		if (ret < 0)
			return ret;
	}

	/*
	 * Pass the stats and embedded data buffers to the IPA. No other
	 * buffers need to be passed.
	 */
	mapBuffers(camera, data->isp_[Isp::Stats].getBuffers(), RPi::MaskStats);
	if (data->sensorMetadata_)
		mapBuffers(camera, data->unicam_[Unicam::Embedded].getBuffers(),
			   RPi::MaskEmbeddedData);

	return 0;
}

void PipelineHandlerRPi::mapBuffers(Camera *camera, const RPi::BufferMap &buffers, unsigned int mask)
{
	RPiCameraData *data = cameraData(camera);
	std::vector<IPABuffer> ipaBuffers;
	/*
	 * Link the FrameBuffers with the id (key value) in the map stored in
	 * the RPi stream object - along with an identifier mask.
	 *
	 * This will allow us to identify buffers passed between the pipeline
	 * handler and the IPA.
	 */
	for (auto const &it : buffers) {
		ipaBuffers.push_back(IPABuffer(mask | it.first,
					       it.second->planes()));
		data->ipaBuffers_.insert(mask | it.first);
	}

	data->ipa_->mapBuffers(ipaBuffers);
}

void RPiCameraData::freeBuffers()
{
	if (ipa_) {
		/*
		 * Copy the buffer ids from the unordered_set to a vector to
		 * pass to the IPA.
		 */
		std::vector<unsigned int> ipaBuffers(ipaBuffers_.begin(),
						     ipaBuffers_.end());
		ipa_->unmapBuffers(ipaBuffers);
		ipaBuffers_.clear();
	}

	for (auto const stream : streams_)
		stream->releaseBuffers();

	buffersAllocated_ = false;
}

void RPiCameraData::frameStarted(uint32_t sequence)
{
	LOG(RPI, Debug) << "frame start " << sequence;

	/* Write any controls for the next frame as soon as we can. */
	delayedCtrls_->applyControls(sequence);
}

int RPiCameraData::loadIPA(ipa::RPi::IPAInitResult *result)
{
	ipa_ = IPAManager::createIPA<ipa::RPi::IPAProxyRPi>(pipe(), 1, 1);

	if (!ipa_)
		return -ENOENT;

	ipa_->statsMetadataComplete.connect(this, &RPiCameraData::statsMetadataComplete);
	ipa_->runIsp.connect(this, &RPiCameraData::runIsp);
	ipa_->embeddedComplete.connect(this, &RPiCameraData::embeddedComplete);
	ipa_->setIspControls.connect(this, &RPiCameraData::setIspControls);
	ipa_->setDelayedControls.connect(this, &RPiCameraData::setDelayedControls);

	/*
	 * The configuration (tuning file) is made from the sensor name unless
	 * the environment variable overrides it.
	 */
	std::string configurationFile;
	char const *configFromEnv = utils::secure_getenv("LIBCAMERA_RPI_TUNING_FILE");
	if (!configFromEnv || *configFromEnv == '\0') {
		std::string model = sensor_->model();
		if (isMonoSensor(sensor_))
			model += "_mono";
		configurationFile = ipa_->configurationFile(model + ".json");
	} else {
		configurationFile = std::string(configFromEnv);
	}

	IPASettings settings(configurationFile, sensor_->model());

	return ipa_->init(settings, result);
}

int RPiCameraData::configureIPA(const CameraConfiguration *config, ipa::RPi::IPAConfigResult *result)
{
	std::map<unsigned int, IPAStream> streamConfig;
	std::map<unsigned int, ControlInfoMap> entityControls;
	ipa::RPi::IPAConfig ipaConfig;

	/* Inform IPA of stream configuration and sensor controls. */
	unsigned int i = 0;
	for (auto const &stream : isp_) {
		if (stream.isExternal()) {
			streamConfig[i++] = IPAStream(
				stream.configuration().pixelFormat,
				stream.configuration().size);
		}
	}

	entityControls.emplace(0, sensor_->controls());
	entityControls.emplace(1, isp_[Isp::Input].dev()->controls());

	/* Always send the user transform to the IPA. */
	ipaConfig.transform = static_cast<unsigned int>(config->transform);

	/* Allocate the lens shading table via dmaHeap and pass to the IPA. */
	if (!lsTable_.isValid()) {
		lsTable_ = SharedFD(dmaHeap_.alloc("ls_grid", ipa::RPi::MaxLsGridSize));
		if (!lsTable_.isValid())
			return -ENOMEM;

		/* Allow the IPA to mmap the LS table via the file descriptor. */
		/*
		 * \todo Investigate if mapping the lens shading table buffer
		 * could be handled with mapBuffers().
		 */
		ipaConfig.lsTableHandle = lsTable_;
	}

	/* We store the IPACameraSensorInfo for digital zoom calculations. */
	int ret = sensor_->sensorInfo(&sensorInfo_);
	if (ret) {
		LOG(RPI, Error) << "Failed to retrieve camera sensor info";
		return ret;
	}

	/* Ready the IPA - it must know about the sensor resolution. */
	ControlList controls;
	ret = ipa_->configure(sensorInfo_, streamConfig, entityControls, ipaConfig,
			      &controls, result);
	if (ret < 0) {
		LOG(RPI, Error) << "IPA configuration failed!";
		return -EPIPE;
	}

	if (!controls.empty())
		setSensorControls(controls);

	return 0;
}

/*
 * enumerateVideoDevices() iterates over the Media Controller topology, starting
 * at the sensor and finishing at Unicam. For each sensor, RPiCameraData stores
 * a unique list of any intermediate video mux or bridge devices connected in a
 * cascade, together with the entity to entity link.
 *
 * Entity pad configuration and link enabling happens at the end of configure().
 * We first disable all pad links on each entity device in the chain, and then
 * selectively enabling the specific links to link sensor to Unicam across all
 * intermediate muxes and bridges.
 *
 * In the cascaded topology below, if Sensor1 is used, the Mux2 -> Mux1 link
 * will be disabled, and Sensor1 -> Mux1 -> Unicam links enabled. Alternatively,
 * if Sensor3 is used, the Sensor2 -> Mux2 and Sensor1 -> Mux1 links are disabled,
 * and Sensor3 -> Mux2 -> Mux1 -> Unicam links are enabled. All other links will
 * remain unchanged.
 *
 *  +----------+
 *  |  Unicam  |
 *  +-----^----+
 *        |
 *    +---+---+
 *    |  Mux1 <-------+
 *    +--^----+       |
 *       |            |
 * +-----+---+    +---+---+
 * | Sensor1 |    |  Mux2 |<--+
 * +---------+    +-^-----+   |
 *                  |         |
 *          +-------+-+   +---+-----+
 *          | Sensor2 |   | Sensor3 |
 *          +---------+   +---------+
 */
void RPiCameraData::enumerateVideoDevices(MediaLink *link)
{
	const MediaPad *sinkPad = link->sink();
	const MediaEntity *entity = sinkPad->entity();
	bool unicamFound = false;

	/* We only deal with Video Mux and Bridge devices in cascade. */
	if (entity->function() != MEDIA_ENT_F_VID_MUX &&
	    entity->function() != MEDIA_ENT_F_VID_IF_BRIDGE)
		return;

	/* Find the source pad for this Video Mux or Bridge device. */
	const MediaPad *sourcePad = nullptr;
	for (const MediaPad *pad : entity->pads()) {
		if (pad->flags() & MEDIA_PAD_FL_SOURCE) {
			/*
			 * We can only deal with devices that have a single source
			 * pad. If this device has multiple source pads, ignore it
			 * and this branch in the cascade.
			 */
			if (sourcePad)
				return;

			sourcePad = pad;
		}
	}

	LOG(RPI, Debug) << "Found video mux device " << entity->name()
			<< " linked to sink pad " << sinkPad->index();

	bridgeDevices_.emplace_back(std::make_unique<V4L2Subdevice>(entity), link);
	bridgeDevices_.back().first->open();

	/*
	 * Iterate through all the sink pad links down the cascade to find any
	 * other Video Mux and Bridge devices.
	 */
	for (MediaLink *l : sourcePad->links()) {
		enumerateVideoDevices(l);
		/* Once we reach the Unicam entity, we are done. */
		if (l->sink()->entity()->name() == "unicam-image") {
			unicamFound = true;
			break;
		}
	}

	/* This identifies the end of our entity enumeration recursion. */
	if (link->source()->entity()->function() == MEDIA_ENT_F_CAM_SENSOR) {
		/*
		* If Unicam is not at the end of this cascade, we cannot configure
		* this topology automatically, so remove all entity references.
		*/
		if (!unicamFound) {
			LOG(RPI, Warning) << "Cannot automatically configure this MC topology!";
			bridgeDevices_.clear();
		}
	}
}

void RPiCameraData::statsMetadataComplete(uint32_t bufferId, const ControlList &controls)
{
	if (!isRunning())
		return;

	FrameBuffer *buffer = isp_[Isp::Stats].getBuffers().at(bufferId & RPi::MaskID);

	handleStreamBuffer(buffer, &isp_[Isp::Stats]);

	/* Add to the Request metadata buffer what the IPA has provided. */
	Request *request = requestQueue_.front();
	request->metadata().merge(controls);

	/*
	 * Inform the sensor of the latest colour gains if it has the
	 * V4L2_CID_NOTIFY_GAINS control (which means notifyGainsUnity_ is set).
	 */
	const auto &colourGains = controls.get(libcamera::controls::ColourGains);
	if (notifyGainsUnity_ && colourGains) {
		/* The control wants linear gains in the order B, Gb, Gr, R. */
		ControlList ctrls(sensor_->controls());
		std::array<int32_t, 4> gains{
			static_cast<int32_t>((*colourGains)[1] * *notifyGainsUnity_),
			*notifyGainsUnity_,
			*notifyGainsUnity_,
			static_cast<int32_t>((*colourGains)[0] * *notifyGainsUnity_)
		};
		ctrls.set(V4L2_CID_NOTIFY_GAINS, Span<const int32_t>{ gains });

		sensor_->setControls(&ctrls);
	}

	state_ = State::IpaComplete;
	handleState();
}

void RPiCameraData::runIsp(uint32_t bufferId)
{
	if (!isRunning())
		return;

	FrameBuffer *buffer = unicam_[Unicam::Image].getBuffers().at(bufferId & RPi::MaskID);

	LOG(RPI, Debug) << "Input re-queue to ISP, buffer id " << (bufferId & RPi::MaskID)
			<< ", timestamp: " << buffer->metadata().timestamp;

	isp_[Isp::Input].queueBuffer(buffer);
	ispOutputCount_ = 0;
	handleState();
}

void RPiCameraData::embeddedComplete(uint32_t bufferId)
{
	if (!isRunning())
		return;

	FrameBuffer *buffer = unicam_[Unicam::Embedded].getBuffers().at(bufferId & RPi::MaskID);
	handleStreamBuffer(buffer, &unicam_[Unicam::Embedded]);
	handleState();
}

void RPiCameraData::setIspControls(const ControlList &controls)
{
	ControlList ctrls = controls;

	if (ctrls.contains(V4L2_CID_USER_BCM2835_ISP_LENS_SHADING)) {
		ControlValue &value =
			const_cast<ControlValue &>(ctrls.get(V4L2_CID_USER_BCM2835_ISP_LENS_SHADING));
		Span<uint8_t> s = value.data();
		bcm2835_isp_lens_shading *ls =
			reinterpret_cast<bcm2835_isp_lens_shading *>(s.data());
		ls->dmabuf = lsTable_.get();
	}

	isp_[Isp::Input].dev()->setControls(&ctrls);
	handleState();
}

void RPiCameraData::setDelayedControls(const ControlList &controls, uint32_t delayContext)
{
	if (!delayedCtrls_->push(controls, delayContext))
		LOG(RPI, Error) << "V4L2 DelayedControl set failed";
	handleState();
}

void RPiCameraData::setSensorControls(ControlList &controls)
{
	/*
	 * We need to ensure that if both VBLANK and EXPOSURE are present, the
	 * former must be written ahead of, and separately from EXPOSURE to avoid
	 * V4L2 rejecting the latter. This is identical to what DelayedControls
	 * does with the priority write flag.
	 *
	 * As a consequence of the below logic, VBLANK gets set twice, and we
	 * rely on the v4l2 framework to not pass the second control set to the
	 * driver as the actual control value has not changed.
	 */
	if (controls.contains(V4L2_CID_EXPOSURE) && controls.contains(V4L2_CID_VBLANK)) {
		ControlList vblank_ctrl;

		vblank_ctrl.set(V4L2_CID_VBLANK, controls.get(V4L2_CID_VBLANK));
		sensor_->setControls(&vblank_ctrl);
	}

	sensor_->setControls(&controls);
}

void RPiCameraData::unicamTimeout()
{
	LOG(RPI, Error) << "Unicam has timed out!";
	LOG(RPI, Error) << "Please check that your camera sensor connector is attached securely.";
	LOG(RPI, Error) << "Alternatively, try another cable and/or sensor.";

	state_ = RPiCameraData::State::Error;
	/*
	 * To allow the application to attempt a recovery from this timeout,
	 * stop all devices streaming, and return any outstanding requests as
	 * incomplete and cancelled.
	 */
	for (auto const stream : streams_)
		stream->dev()->streamOff();

	clearIncompleteRequests();
}

void RPiCameraData::unicamBufferDequeue(FrameBuffer *buffer)
{
	RPi::Stream *stream = nullptr;
	int index;

	if (!isRunning())
		return;

	for (RPi::Stream &s : unicam_) {
		index = s.getBufferId(buffer);
		if (index != -1) {
			stream = &s;
			break;
		}
	}

	/* The buffer must belong to one of our streams. */
	ASSERT(stream);

	LOG(RPI, Debug) << "Stream " << stream->name() << " buffer dequeue"
			<< ", buffer id " << index
			<< ", timestamp: " << buffer->metadata().timestamp;

	if (stream == &unicam_[Unicam::Image]) {
		/*
		 * Lookup the sensor controls used for this frame sequence from
		 * DelayedControl and queue them along with the frame buffer.
		 */
		auto [ctrl, delayContext] = delayedCtrls_->get(buffer->metadata().sequence);
		/*
		 * Add the frame timestamp to the ControlList for the IPA to use
		 * as it does not receive the FrameBuffer object.
		 */
		ctrl.set(controls::SensorTimestamp, buffer->metadata().timestamp);
		bayerQueue_.push({ buffer, std::move(ctrl), delayContext });
	} else {
		embeddedQueue_.push(buffer);
	}

	handleState();
}

void RPiCameraData::ispInputDequeue(FrameBuffer *buffer)
{
	if (!isRunning())
		return;

	LOG(RPI, Debug) << "Stream ISP Input buffer complete"
			<< ", buffer id " << unicam_[Unicam::Image].getBufferId(buffer)
			<< ", timestamp: " << buffer->metadata().timestamp;

	/* The ISP input buffer gets re-queued into Unicam. */
	handleStreamBuffer(buffer, &unicam_[Unicam::Image]);
	handleState();
}

void RPiCameraData::ispOutputDequeue(FrameBuffer *buffer)
{
	RPi::Stream *stream = nullptr;
	int index;

	if (!isRunning())
		return;

	for (RPi::Stream &s : isp_) {
		index = s.getBufferId(buffer);
		if (index != -1) {
			stream = &s;
			break;
		}
	}

	/* The buffer must belong to one of our ISP output streams. */
	ASSERT(stream);

	LOG(RPI, Debug) << "Stream " << stream->name() << " buffer complete"
			<< ", buffer id " << index
			<< ", timestamp: " << buffer->metadata().timestamp;

	/*
	 * ISP statistics buffer must not be re-queued or sent back to the
	 * application until after the IPA signals so.
	 */
	if (stream == &isp_[Isp::Stats]) {
		ipa_->signalStatReady(RPi::MaskStats | static_cast<unsigned int>(index),
				      requestQueue_.front()->sequence());
	} else {
		/* Any other ISP output can be handed back to the application now. */
		handleStreamBuffer(buffer, stream);
	}

	/*
	 * Increment the number of ISP outputs generated.
	 * This is needed to track dropped frames.
	 */
	ispOutputCount_++;

	handleState();
}

void RPiCameraData::clearIncompleteRequests()
{
	/*
	 * All outstanding requests (and associated buffers) must be returned
	 * back to the application.
	 */
	while (!requestQueue_.empty()) {
		Request *request = requestQueue_.front();

		for (auto &b : request->buffers()) {
			FrameBuffer *buffer = b.second;
			/*
			 * Has the buffer already been handed back to the
			 * request? If not, do so now.
			 */
			if (buffer->request()) {
				buffer->_d()->cancel();
				pipe()->completeBuffer(request, buffer);
			}
		}

		pipe()->completeRequest(request);
		requestQueue_.pop_front();
	}
}

void RPiCameraData::handleStreamBuffer(FrameBuffer *buffer, RPi::Stream *stream)
{
	/*
	 * It is possible to be here without a pending request, so check
	 * that we actually have one to action, otherwise we just return
	 * buffer back to the stream.
	 */
	Request *request = requestQueue_.empty() ? nullptr : requestQueue_.front();
	if (!dropFrameCount_ && request && request->findBuffer(stream) == buffer) {
		/*
		 * Check if this is an externally provided buffer, and if
		 * so, we must stop tracking it in the pipeline handler.
		 */
		handleExternalBuffer(buffer, stream);
		/*
		 * Tag the buffer as completed, returning it to the
		 * application.
		 */
		pipe()->completeBuffer(request, buffer);
	} else {
		/*
		 * This buffer was not part of the Request (which happens if an
		 * internal buffer was used for an external stream, or
		 * unconditionally for internal streams), or there is no pending
		 * request, so we can recycle it.
		 */
		stream->returnBuffer(buffer);
	}
}

void RPiCameraData::handleExternalBuffer(FrameBuffer *buffer, RPi::Stream *stream)
{
	unsigned int id = stream->getBufferId(buffer);

	if (!(id & RPi::MaskExternalBuffer))
		return;

	/* Stop the Stream object from tracking the buffer. */
	stream->removeExternalBuffer(buffer);
}

void RPiCameraData::handleState()
{
	switch (state_) {
	case State::Stopped:
	case State::Busy:
	case State::Error:
		break;

	case State::IpaComplete:
		/* If the request is completed, we will switch to Idle state. */
		checkRequestCompleted();
		/*
		 * No break here, we want to try running the pipeline again.
		 * The fallthrough clause below suppresses compiler warnings.
		 */
		[[fallthrough]];

	case State::Idle: