summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/drm_atomic_helper.c
blob: 3ef2ac52ce942c303fbec865587fa7b95933ad15 (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
/*
 * Copyright (C) 2014 Red Hat
 * Copyright (C) 2014 Intel Corp.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors:
 * Rob Clark <robdclark@gmail.com>
 * Daniel Vetter <daniel.vetter@ffwll.ch>
 */

#include <linux/dma-fence.h>
#include <linux/ktime.h>

#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_atomic_uapi.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_device.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_print.h>
#include <drm/drm_self_refresh_helper.h>
#include <drm/drm_vblank.h>
#include <drm/drm_writeback.h>

#include "drm_crtc_helper_internal.h"
#include "drm_crtc_internal.h"

/**
 * DOC: overview
 *
 * This helper library provides implementations of check and commit functions on
 * top of the CRTC modeset helper callbacks and the plane helper callbacks. It
 * also provides convenience implementations for the atomic state handling
 * callbacks for drivers which don't need to subclass the drm core structures to
 * add their own additional internal state.
 *
 * This library also provides default implementations for the check callback in
 * drm_atomic_helper_check() and for the commit callback with
 * drm_atomic_helper_commit(). But the individual stages and callbacks are
 * exposed to allow drivers to mix and match and e.g. use the plane helpers only
 * together with a driver private modeset implementation.
 *
 * This library also provides implementations for all the legacy driver
 * interfaces on top of the atomic interface. See drm_atomic_helper_set_config(),
 * drm_atomic_helper_disable_plane(), drm_atomic_helper_disable_plane() and the
 * various functions to implement set_property callbacks. New drivers must not
 * implement these functions themselves but must use the provided helpers.
 *
 * The atomic helper uses the same function table structures as all other
 * modesetting helpers. See the documentation for &struct drm_crtc_helper_funcs,
 * struct &drm_encoder_helper_funcs and &struct drm_connector_helper_funcs. It
 * also shares the &struct drm_plane_helper_funcs function table with the plane
 * helpers.
 */
static void
drm_atomic_helper_plane_changed(struct drm_atomic_state *state,
				struct drm_plane_state *old_plane_state,
				struct drm_plane_state *plane_state,
				struct drm_plane *plane)
{
	struct drm_crtc_state *crtc_state;

	if (old_plane_state->crtc) {
		crtc_state = drm_atomic_get_new_crtc_state(state,
							   old_plane_state->crtc);

		if (WARN_ON(!crtc_state))
			return;

		crtc_state->planes_changed = true;
	}

	if (plane_state->crtc) {
		crtc_state = drm_atomic_get_new_crtc_state(state, plane_state->crtc);

		if (WARN_ON(!crtc_state))
			return;

		crtc_state->planes_changed = true;
	}
}

/*
 * For connectors that support multiple encoders, either the
 * .atomic_best_encoder() or .best_encoder() operation must be implemented.
 */
static struct drm_encoder *
pick_single_encoder_for_connector(struct drm_connector *connector)
{
	WARN_ON(connector->encoder_ids[1]);
	return drm_encoder_find(connector->dev, NULL, connector->encoder_ids[0]);
}

static int handle_conflicting_encoders(struct drm_atomic_state *state,
				       bool disable_conflicting_encoders)
{
	struct drm_connector_state *new_conn_state;
	struct drm_connector *connector;
	struct drm_connector_list_iter conn_iter;
	struct drm_encoder *encoder;
	unsigned encoder_mask = 0;
	int i, ret = 0;

	/*
	 * First loop, find all newly assigned encoders from the connectors
	 * part of the state. If the same encoder is assigned to multiple
	 * connectors bail out.
	 */
	for_each_new_connector_in_state(state, connector, new_conn_state, i) {
		const struct drm_connector_helper_funcs *funcs = connector->helper_private;
		struct drm_encoder *new_encoder;

		if (!new_conn_state->crtc)
			continue;

		if (funcs->atomic_best_encoder)
			new_encoder = funcs->atomic_best_encoder(connector, new_conn_state);
		else if (funcs->best_encoder)
			new_encoder = funcs->best_encoder(connector);
		else
			new_encoder = pick_single_encoder_for_connector(connector);

		if (new_encoder) {
			if (encoder_mask & drm_encoder_mask(new_encoder)) {
				DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] on [CONNECTOR:%d:%s] already assigned\n",
					new_encoder->base.id, new_encoder->name,
					connector->base.id, connector->name);

				return -EINVAL;
			}

			encoder_mask |= drm_encoder_mask(new_encoder);
		}
	}

	if (!encoder_mask)
		return 0;

	/*
	 * Second loop, iterate over all connectors not part of the state.
	 *
	 * If a conflicting encoder is found and disable_conflicting_encoders
	 * is not set, an error is returned. Userspace can provide a solution
	 * through the atomic ioctl.
	 *
	 * If the flag is set conflicting connectors are removed from the crtc
	 * and the crtc is disabled if no encoder is left. This preserves
	 * compatibility with the legacy set_config behavior.
	 */
	drm_connector_list_iter_begin(state->dev, &conn_iter);
	drm_for_each_connector_iter(connector, &conn_iter) {
		struct drm_crtc_state *crtc_state;

		if (drm_atomic_get_new_connector_state(state, connector))
			continue;

		encoder = connector->state->best_encoder;
		if (!encoder || !(encoder_mask & drm_encoder_mask(encoder)))
			continue;

		if (!disable_conflicting_encoders) {
			DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s] by [CONNECTOR:%d:%s]\n",
					 encoder->base.id, encoder->name,
					 connector->state->crtc->base.id,
					 connector->state->crtc->name,
					 connector->base.id, connector->name);
			ret = -EINVAL;
			goto out;
		}

		new_conn_state = drm_atomic_get_connector_state(state, connector);
		if (IS_ERR(new_conn_state)) {
			ret = PTR_ERR(new_conn_state);
			goto out;
		}

		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s], disabling [CONNECTOR:%d:%s]\n",
				 encoder->base.id, encoder->name,
				 new_conn_state->crtc->base.id, new_conn_state->crtc->name,
				 connector->base.id, connector->name);

		crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc);

		ret = drm_atomic_set_crtc_for_connector(new_conn_state, NULL);
		if (ret)
			goto out;

		if (!crtc_state->connector_mask) {
			ret = drm_atomic_set_mode_prop_for_crtc(crtc_state,
								NULL);
			if (ret < 0)
				goto out;

			crtc_state->active = false;
		}
	}
out:
	drm_connector_list_iter_end(&conn_iter);

	return ret;
}

static void
set_best_encoder(struct drm_atomic_state *state,
		 struct drm_connector_state *conn_state,
		 struct drm_encoder *encoder)
{
	struct drm_crtc_state *crtc_state;
	struct drm_crtc *crtc;

	if (conn_state->best_encoder) {
		/* Unset the encoder_mask in the old crtc state. */
		crtc = conn_state->connector->state->crtc;

		/* A NULL crtc is an error here because we should have
		 *  duplicated a NULL best_encoder when crtc was NULL.
		 * As an exception restoring duplicated atomic state
		 * during resume is allowed, so don't warn when
		 * best_encoder is equal to encoder we intend to set.
		 */
		WARN_ON(!crtc && encoder != conn_state->best_encoder);
		if (crtc) {
			crtc_state = drm_atomic_get_new_crtc_state(state, crtc);

			crtc_state->encoder_mask &=
				~drm_encoder_mask(conn_state->best_encoder);
		}
	}

	if (encoder) {
		crtc = conn_state->crtc;
		WARN_ON(!crtc);
		if (crtc) {
			crtc_state = drm_atomic_get_new_crtc_state(state, crtc);

			crtc_state->encoder_mask |=
				drm_encoder_mask(encoder);
		}
	}

	conn_state->best_encoder = encoder;
}

static void
steal_encoder(struct drm_atomic_state *state,
	      struct drm_encoder *encoder)
{
	struct drm_crtc_state *crtc_state;
	struct drm_connector *connector;
	struct drm_connector_state *old_connector_state, *new_connector_state;
	int i;

	for_each_oldnew_connector_in_state(state, connector, old_connector_state, new_connector_state, i) {
		struct drm_crtc *encoder_crtc;

		if (new_connector_state->best_encoder != encoder)
			continue;

		encoder_crtc = old_connector_state->crtc;

		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] in use on [CRTC:%d:%s], stealing it\n",
				 encoder->base.id, encoder->name,
				 encoder_crtc->base.id, encoder_crtc->name);

		set_best_encoder(state, new_connector_state, NULL);

		crtc_state = drm_atomic_get_new_crtc_state(state, encoder_crtc);
		crtc_state->connectors_changed = true;

		return;
	}
}

static int
update_connector_routing(struct drm_atomic_state *state,
			 struct drm_connector *connector,
			 struct drm_connector_state *old_connector_state,
			 struct drm_connector_state *new_connector_state)
{
	const struct drm_connector_helper_funcs *funcs;
	struct drm_encoder *new_encoder;
	struct drm_crtc_state *crtc_state;

	DRM_DEBUG_ATOMIC("Updating routing for [CONNECTOR:%d:%s]\n",
			 connector->base.id,
			 connector->name);

	if (old_connector_state->crtc != new_connector_state->crtc) {
		if (old_connector_state->crtc) {
			crtc_state = drm_atomic_get_new_crtc_state(state, old_connector_state->crtc);
			crtc_state->connectors_changed = true;
		}

		if (new_connector_state->crtc) {
			crtc_state = drm_atomic_get_new_crtc_state(state, new_connector_state->crtc);
			crtc_state->connectors_changed = true;
		}
	}

	if (!new_connector_state->crtc) {
		DRM_DEBUG_ATOMIC("Disabling [CONNECTOR:%d:%s]\n",
				connector->base.id,
				connector->name);

		set_best_encoder(state, new_connector_state, NULL);

		return 0;
	}

	crtc_state = drm_atomic_get_new_crtc_state(state,
						   new_connector_state->crtc);
	/*
	 * For compatibility with legacy users, we want to make sure that
	 * we allow DPMS On->Off modesets on unregistered connectors. Modesets
	 * which would result in anything else must be considered invalid, to
	 * avoid turning on new displays on dead connectors.
	 *
	 * Since the connector can be unregistered at any point during an
	 * atomic check or commit, this is racy. But that's OK: all we care
	 * about is ensuring that userspace can't do anything but shut off the
	 * display on a connector that was destroyed after it's been notified,
	 * not before.
	 *
	 * Additionally, we also want to ignore connector registration when
	 * we're trying to restore an atomic state during system resume since
	 * there's a chance the connector may have been destroyed during the
	 * process, but it's better to ignore that then cause
	 * drm_atomic_helper_resume() to fail.
	 */
	if (!state->duplicated && drm_connector_is_unregistered(connector) &&
	    crtc_state->active) {
		DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] is not registered\n",
				 connector->base.id, connector->name);
		return -EINVAL;
	}

	funcs = connector->helper_private;

	if (funcs->atomic_best_encoder)
		new_encoder = funcs->atomic_best_encoder(connector,
							 new_connector_state);
	else if (funcs->best_encoder)
		new_encoder = funcs->best_encoder(connector);
	else
		new_encoder = pick_single_encoder_for_connector(connector);

	if (!new_encoder) {
		DRM_DEBUG_ATOMIC("No suitable encoder found for [CONNECTOR:%d:%s]\n",
				 connector->base.id,
				 connector->name);
		return -EINVAL;
	}

	if (!drm_encoder_crtc_ok(new_encoder, new_connector_state->crtc)) {
		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] incompatible with [CRTC:%d:%s]\n",
				 new_encoder->base.id,
				 new_encoder->name,
				 new_connector_state->crtc->base.id,
				 new_connector_state->crtc->name);
		return -EINVAL;
	}

	if (new_encoder == new_connector_state->best_encoder) {
		set_best_encoder(state, new_connector_state, new_encoder);

		DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] keeps [ENCODER:%d:%s], now on [CRTC:%d:%s]\n",
				 connector->base.id,
				 connector->name,
				 new_encoder->base.id,
				 new_encoder->name,
				 new_connector_state->crtc->base.id,
				 new_connector_state->crtc->name);

		return 0;
	}

	steal_encoder(state, new_encoder);

	set_best_encoder(state, new_connector_state, new_encoder);

	crtc_state->connectors_changed = true;

	DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] using [ENCODER:%d:%s] on [CRTC:%d:%s]\n",
			 connector->base.id,
			 connector->name,
			 new_encoder->base.id,
			 new_encoder->name,
			 new_connector_state->crtc->base.id,
			 new_connector_state->crtc->name);

	return 0;
}

static int
mode_fixup(struct drm_atomic_state *state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *new_crtc_state;
	struct drm_connector *connector;
	struct drm_connector_state *new_conn_state;
	int i;
	int ret;

	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
		if (!new_crtc_state->mode_changed &&
		    !new_crtc_state->connectors_changed)
			continue;

		drm_mode_copy(&new_crtc_state->adjusted_mode, &new_crtc_state->mode);
	}

	for_each_new_connector_in_state(state, connector, new_conn_state, i) {
		const struct drm_encoder_helper_funcs *funcs;
		struct drm_encoder *encoder;

		WARN_ON(!!new_conn_state->best_encoder != !!new_conn_state->crtc);

		if (!new_conn_state->crtc || !new_conn_state->best_encoder)
			continue;

		new_crtc_state =
			drm_atomic_get_new_crtc_state(state, new_conn_state->crtc);

		/*
		 * Each encoder has at most one connector (since we always steal
		 * it away), so we won't call ->mode_fixup twice.
		 */
		encoder = new_conn_state->best_encoder;
		funcs = encoder->helper_private;

		ret = drm_bridge_mode_fixup(encoder->bridge, &new_crtc_state->mode,
				&new_crtc_state->adjusted_mode);
		if (!ret) {
			DRM_DEBUG_ATOMIC("Bridge fixup failed\n");
			return -EINVAL;
		}

		if (funcs && funcs->atomic_check) {
			ret = funcs->atomic_check(encoder, new_crtc_state,
						  new_conn_state);
			if (ret) {
				DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] check failed\n",
						 encoder->base.id, encoder->name);
				return ret;
			}
		} else if (funcs && funcs->mode_fixup) {
			ret = funcs->mode_fixup(encoder, &new_crtc_state->mode,
						&new_crtc_state->adjusted_mode);
			if (!ret) {
				DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] fixup failed\n",
						 encoder->base.id, encoder->name);
				return -EINVAL;
			}
		}
	}

	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
		const struct drm_crtc_helper_funcs *funcs;

		if (!new_crtc_state->enable)
			continue;

		if (!new_crtc_state->mode_changed &&
		    !new_crtc_state->connectors_changed)
			continue;

		funcs = crtc->helper_private;
		if (!funcs->mode_fixup)
			continue;

		ret = funcs->mode_fixup(crtc, &new_crtc_state->mode,
					&new_crtc_state->adjusted_mode);
		if (!ret) {
			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] fixup failed\n",
					 crtc->base.id, crtc->name);
			return -EINVAL;
		}
	}

	return 0;
}

static enum drm_mode_status mode_valid_path(struct drm_connector *connector,
					    struct drm_encoder *encoder,
					    struct drm_crtc *crtc,
					    const struct drm_display_mode *mode)
{
	enum drm_mode_status ret;

	ret = drm_encoder_mode_valid(encoder, mode);
	if (ret != MODE_OK) {
		DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] mode_valid() failed\n",
				encoder->base.id, encoder->name);
		return ret;
	}

	ret = drm_bridge_mode_valid(encoder->bridge, mode);
	if (ret != MODE_OK) {
		DRM_DEBUG_ATOMIC("[BRIDGE] mode_valid() failed\n");
		return ret;
	}

	ret = drm_crtc_mode_valid(crtc, mode);
	if (ret != MODE_OK) {
		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] mode_valid() failed\n",
				crtc->base.id, crtc->name);
		return ret;
	}

	return ret;
}

static int
mode_valid(struct drm_atomic_state *state)
{
	struct drm_connector_state *conn_state;
	struct drm_connector *connector;
	int i;

	for_each_new_connector_in_state(state, connector, conn_state, i) {
		struct drm_encoder *encoder = conn_state->best_encoder;
		struct drm_crtc *crtc = conn_state->crtc;
		struct drm_crtc_state *crtc_state;
		enum drm_mode_status mode_status;
		const struct drm_display_mode *mode;

		if (!crtc || !encoder)
			continue;

		crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
		if (!crtc_state)
			continue;
		if (!crtc_state->mode_changed && !crtc_state->connectors_changed)
			continue;

		mode = &crtc_state->mode;

		mode_status = mode_valid_path(connector, encoder, crtc, mode);
		if (mode_status != MODE_OK)
			return -EINVAL;
	}

	return 0;
}

/**
 * drm_atomic_helper_check_modeset - validate state object for modeset changes
 * @dev: DRM device
 * @state: the driver state object
 *
 * Check the state object to see if the requested state is physically possible.
 * This does all the crtc and connector related computations for an atomic
 * update and adds any additional connectors needed for full modesets. It calls
 * the various per-object callbacks in the follow order:
 *
 * 1. &drm_connector_helper_funcs.atomic_best_encoder for determining the new encoder.
 * 2. &drm_connector_helper_funcs.atomic_check to validate the connector state.
 * 3. If it's determined a modeset is needed then all connectors on the affected crtc
 *    crtc are added and &drm_connector_helper_funcs.atomic_check is run on them.
 * 4. &drm_encoder_helper_funcs.mode_valid, &drm_bridge_funcs.mode_valid and
 *    &drm_crtc_helper_funcs.mode_valid are called on the affected components.
 * 5. &drm_bridge_funcs.mode_fixup is called on all encoder bridges.
 * 6. &drm_encoder_helper_funcs.atomic_check is called to validate any encoder state.
 *    This function is only called when the encoder will be part of a configured crtc,
 *    it must not be used for implementing connector property validation.
 *    If this function is NULL, &drm_atomic_encoder_helper_funcs.mode_fixup is called
 *    instead.
 * 7. &drm_crtc_helper_funcs.mode_fixup is called last, to fix up the mode with crtc constraints.
 *
 * &drm_crtc_state.mode_changed is set when the input mode is changed.
 * &drm_crtc_state.connectors_changed is set when a connector is added or
 * removed from the crtc.  &drm_crtc_state.active_changed is set when
 * &drm_crtc_state.active changes, which is used for DPMS.
 * See also: drm_atomic_crtc_needs_modeset()
 *
 * IMPORTANT:
 *
 * Drivers which set &drm_crtc_state.mode_changed (e.g. in their
 * &drm_plane_helper_funcs.atomic_check hooks if a plane update can't be done
 * without a full modeset) _must_ call this function afterwards after that
 * change. It is permitted to call this function multiple times for the same
 * update, e.g. when the &drm_crtc_helper_funcs.atomic_check functions depend
 * upon the adjusted dotclock for fifo space allocation and watermark
 * computation.
 *
 * RETURNS:
 * Zero for success or -errno
 */
int
drm_atomic_helper_check_modeset(struct drm_device *dev,
				struct drm_atomic_state *state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	struct drm_connector *connector;
	struct drm_connector_state *old_connector_state, *new_connector_state;
	int i, ret;
	unsigned connectors_mask = 0;

	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
		bool has_connectors =
			!!new_crtc_state->connector_mask;

		WARN_ON(!drm_modeset_is_locked(&crtc->mutex));

		if (!drm_mode_equal(&old_crtc_state->mode, &new_crtc_state->mode)) {
			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] mode changed\n",
					 crtc->base.id, crtc->name);
			new_crtc_state->mode_changed = true;
		}

		if (old_crtc_state->enable != new_crtc_state->enable) {
			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] enable changed\n",
					 crtc->base.id, crtc->name);

			/*
			 * For clarity this assignment is done here, but
			 * enable == 0 is only true when there are no
			 * connectors and a NULL mode.
			 *
			 * The other way around is true as well. enable != 0
			 * iff connectors are attached and a mode is set.
			 */
			new_crtc_state->mode_changed = true;
			new_crtc_state->connectors_changed = true;
		}

		if (old_crtc_state->active != new_crtc_state->active) {
			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] active changed\n",
					 crtc->base.id, crtc->name);
			new_crtc_state->active_changed = true;
		}

		if (new_crtc_state->enable != has_connectors) {
			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] enabled/connectors mismatch\n",
					 crtc->base.id, crtc->name);

			return -EINVAL;
		}
	}

	ret = handle_conflicting_encoders(state, false);
	if (ret)
		return ret;

	for_each_oldnew_connector_in_state(state, connector, old_connector_state, new_connector_state, i) {
		const struct drm_connector_helper_funcs *funcs = connector->helper_private;

		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));

		/*
		 * This only sets crtc->connectors_changed for routing changes,
		 * drivers must set crtc->connectors_changed themselves when
		 * connector properties need to be updated.
		 */
		ret = update_connector_routing(state, connector,
					       old_connector_state,
					       new_connector_state);
		if (ret)
			return ret;
		if (old_connector_state->crtc) {
			new_crtc_state = drm_atomic_get_new_crtc_state(state,
								       old_connector_state->crtc);
			if (old_connector_state->link_status !=
			    new_connector_state->link_status)
				new_crtc_state->connectors_changed = true;

			if (old_connector_state->max_requested_bpc !=
			    new_connector_state->max_requested_bpc)
				new_crtc_state->connectors_changed = true;
		}

		if (funcs->atomic_check)
			ret = funcs->atomic_check(connector, state);
		if (ret)
			return ret;

		connectors_mask |= BIT(i);
	}

	/*
	 * After all the routing has been prepared we need to add in any
	 * connector which is itself unchanged, but whose crtc changes its
	 * configuration. This must be done before calling mode_fixup in case a
	 * crtc only changed its mode but has the same set of connectors.
	 */
	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
		if (!drm_atomic_crtc_needs_modeset(new_crtc_state))
			continue;

		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] needs all connectors, enable: %c, active: %c\n",
				 crtc->base.id, crtc->name,
				 new_crtc_state->enable ? 'y' : 'n',
				 new_crtc_state->active ? 'y' : 'n');

		ret = drm_atomic_add_affected_connectors(state, crtc);
		if (ret != 0)
			return ret;

		ret = drm_atomic_add_affected_planes(state, crtc);
		if (ret != 0)
			return ret;
	}

	/*
	 * Iterate over all connectors again, to make sure atomic_check()
	 * has been called on them when a modeset is forced.
	 */
	for_each_oldnew_connector_in_state(state, connector, old_connector_state, new_connector_state, i) {
		const struct drm_connector_helper_funcs *funcs = connector->helper_private;

		if (connectors_mask & BIT(i))
			continue;

		if (funcs->atomic_check)
			ret = funcs->atomic_check(connector, state);
		if (ret)
			return ret;
	}

	ret = mode_valid(state);
	if (ret)
		return ret;

	return mode_fixup(state);
}
EXPORT_SYMBOL(drm_atomic_helper_check_modeset);

/**
 * drm_atomic_helper_check_plane_state() - Check plane state for validity
 * @plane_state: plane state to check
 * @crtc_state: crtc state to check
 * @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
 * @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
 * @can_position: is it legal to position the plane such that it
 *                doesn't cover the entire crtc?  This will generally
 *                only be false for primary planes.
 * @can_update_disabled: can the plane be updated while the crtc
 *                       is disabled?
 *
 * Checks that a desired plane update is valid, and updates various
 * bits of derived state (clipped coordinates etc.). Drivers that provide
 * their own plane handling rather than helper-provided implementations may
 * still wish to call this function to avoid duplication of error checking
 * code.
 *
 * RETURNS:
 * Zero if update appears valid, error code on failure
 */
int drm_atomic_helper_check_plane_state(struct drm_plane_state *plane_state,
					const struct drm_crtc_state *crtc_state,
					int min_scale,
					int max_scale,
					bool can_position,
					bool can_update_disabled)
{
	struct drm_framebuffer *fb = plane_state->fb;
	struct drm_rect *src = &plane_state->src;
	struct drm_rect *dst = &plane_state->dst;
	unsigned int rotation = plane_state->rotation;
	struct drm_rect clip = {};
	int hscale, vscale;

	WARN_ON(plane_state->crtc && plane_state->crtc != crtc_state->crtc);

	*src = drm_plane_state_src(plane_state);
	*dst = drm_plane_state_dest(plane_state);

	if (!fb) {
		plane_state->visible = false;
		return 0;
	}

	/* crtc should only be NULL when disabling (i.e., !fb) */
	if (WARN_ON(!plane_state->crtc)) {
		plane_state->visible = false;
		return 0;
	}

	if (!crtc_state->enable && !can_update_disabled) {
		DRM_DEBUG_KMS("Cannot update plane of a disabled CRTC.\n");
		return -EINVAL;
	}

	drm_rect_rotate(src, fb->width << 16, fb->height << 16, rotation);

	/* Check scaling */
	hscale = drm_rect_calc_hscale(src, dst, min_scale, max_scale);
	vscale = drm_rect_calc_vscale(src, dst, min_scale, max_scale);
	if (hscale < 0 || vscale < 0) {
		DRM_DEBUG_KMS("Invalid scaling of plane\n");
		drm_rect_debug_print("src: ", &plane_state->src, true);
		drm_rect_debug_print("dst: ", &plane_state->dst, false);
		return -ERANGE;
	}

	if (crtc_state->enable)
		drm_mode_get_hv_timing(&crtc_state->mode, &clip.x2, &clip.y2);

	plane_state->visible = drm_rect_clip_scaled(src, dst, &clip);

	drm_rect_rotate_inv(src, fb->width << 16, fb->height << 16, rotation);

	if (!plane_state->visible)
		/*
		 * Plane isn't visible; some drivers can handle this
		 * so we just return success here.  Drivers that can't
		 * (including those that use the primary plane helper's
		 * update function) will return an error from their
		 * update_plane handler.
		 */
		return 0;

	if (!can_position && !drm_rect_equals(dst, &clip)) {
		DRM_DEBUG_KMS("Plane must cover entire CRTC\n");
		drm_rect_debug_print("dst: ", dst, false);
		drm_rect_debug_print("clip: ", &clip, false);
		return -EINVAL;
	}

	return 0;
}
EXPORT_SYMBOL(drm_atomic_helper_check_plane_state);

/**
 * drm_atomic_helper_check_planes - validate state object for planes changes
 * @dev: DRM device
 * @state: the driver state object
 *
 * Check the state object to see if the requested state is physically possible.
 * This does all the plane update related checks using by calling into the
 * &drm_crtc_helper_funcs.atomic_check and &drm_plane_helper_funcs.atomic_check
 * hooks provided by the driver.
 *
 * It also sets &drm_crtc_state.planes_changed to indicate that a crtc has
 * updated planes.
 *
 * RETURNS:
 * Zero for success or -errno
 */
int
drm_atomic_helper_check_planes(struct drm_device *dev,
			       struct drm_atomic_state *state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *new_crtc_state;
	struct drm_plane *plane;
	struct drm_plane_state *new_plane_state, *old_plane_state;
	int i, ret = 0;

	for_each_oldnew_plane_in_state(state, plane, old_plane_state, new_plane_state, i) {
		const struct drm_plane_helper_funcs *funcs;

		WARN_ON(!drm_modeset_is_locked(&plane->mutex));

		funcs = plane->helper_private;

		drm_atomic_helper_plane_changed(state, old_plane_state, new_plane_state, plane);

		drm_atomic_helper_check_plane_damage(state, new_plane_state);

		if (!funcs || !funcs->atomic_check)
			continue;

		ret = funcs->atomic_check(plane, new_plane_state);
		if (ret) {
			DRM_DEBUG_ATOMIC("[PLANE:%d:%s] atomic driver check failed\n",
					 plane->base.id, plane->name);
			return ret;
		}
	}

	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i) {
		const struct drm_crtc_helper_funcs *funcs;

		funcs = crtc->helper_private;

		if (!funcs || !funcs->atomic_check)
			continue;

		ret = funcs->atomic_check(crtc, new_crtc_state);
		if (ret) {
			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] atomic driver check failed\n",
					 crtc->base.id, crtc->name);
			return ret;
		}
	}

	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_check_planes);

/**
 * drm_atomic_helper_check - validate state object
 * @dev: DRM device
 * @state: the driver state object
 *
 * Check the state object to see if the requested state is physically possible.
 * Only crtcs and planes have check callbacks, so for any additional (global)
 * checking that a driver needs it can simply wrap that around this function.
 * Drivers without such needs can directly use this as their
 * &drm_mode_config_funcs.atomic_check callback.
 *
 * This just wraps the two parts of the state checking for planes and modeset
 * state in the default order: First it calls drm_atomic_helper_check_modeset()
 * and then drm_atomic_helper_check_planes(). The assumption is that the
 * @drm_plane_helper_funcs.atomic_check and @drm_crtc_helper_funcs.atomic_check
 * functions depend upon an updated adjusted_mode.clock to e.g. properly compute
 * watermarks.
 *
 * Note that zpos normalization will add all enable planes to the state which
 * might not desired for some drivers.
 * For example enable/disable of a cursor plane which have fixed zpos value
 * would trigger all other enabled planes to be forced to the state change.
 *
 * RETURNS:
 * Zero for success or -errno
 */
int drm_atomic_helper_check(struct drm_device *dev,
			    struct drm_atomic_state *state)
{
	int ret;

	ret = drm_atomic_helper_check_modeset(dev, state);
	if (ret)
		return ret;

	if (dev->mode_config.normalize_zpos) {
		ret = drm_atomic_normalize_zpos(dev, state);
		if (ret)
			return ret;
	}

	ret = drm_atomic_helper_check_planes(dev, state);
	if (ret)
		return ret;

	if (state->legacy_cursor_update)
		state->async_update = !drm_atomic_helper_async_check(dev, state);

	drm_self_refresh_helper_alter_state(state);

	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_check);

static bool
crtc_needs_disable(struct drm_crtc_state *old_state,
		   struct drm_crtc_state *new_state)
{
	/*
	 * No new_state means the crtc is off, so the only criteria is whether
	 * it's currently active or in self refresh mode.
	 */
	if (!new_state)
		return drm_atomic_crtc_effectively_active(old_state);

	/*
	 * We need to run through the crtc_funcs->disable() function if the crtc
	 * is currently on, if it's transitioning to self refresh mode, or if
	 * it's in self refresh mode and needs to be fully disabled.
	 */
	return old_state->active ||
	       (old_state->self_refresh_active && !new_state->enable) ||
	       new_state->self_refresh_active;
}

static void
disable_outputs(struct drm_device *dev, struct drm_atomic_state *old_state)
{
	struct drm_connector *connector;
	struct drm_connector_state *old_conn_state, *new_conn_state;
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	int i;

	for_each_oldnew_connector_in_state(old_state, connector, old_conn_state, new_conn_state, i) {
		const struct drm_encoder_helper_funcs *funcs;
		struct drm_encoder *encoder;

		/* Shut down everything that's in the changeset and currently
		 * still on. So need to check the old, saved state. */
		if (!old_conn_state->crtc)
			continue;

		old_crtc_state = drm_atomic_get_old_crtc_state(old_state, old_conn_state->crtc);

		if (new_conn_state->crtc)
			new_crtc_state = drm_atomic_get_new_crtc_state(
						old_state,
						new_conn_state->crtc);
		else
			new_crtc_state = NULL;

		if (!crtc_needs_disable(old_crtc_state, new_crtc_state) ||
		    !drm_atomic_crtc_needs_modeset(old_conn_state->crtc->state))
			continue;

		encoder = old_conn_state->best_encoder;

		/* We shouldn't get this far if we didn't previously have
		 * an encoder.. but WARN_ON() rather than explode.
		 */
		if (WARN_ON(!encoder))
			continue;

		funcs = encoder->helper_private;

		DRM_DEBUG_ATOMIC("disabling [ENCODER:%d:%s]\n",
				 encoder->base.id, encoder->name);

		/*
		 * Each encoder has at most one connector (since we always steal
		 * it away), so we won't call disable hooks twice.
		 */
		drm_atomic_bridge_disable(encoder->bridge, old_state);

		/* Right function depends upon target state. */
		if (funcs) {
			if (funcs->atomic_disable)
				funcs->atomic_disable(encoder, old_state);
			else if (new_conn_state->crtc && funcs->prepare)
				funcs->prepare(encoder);
			else if (funcs->disable)
				funcs->disable(encoder);
			else if (funcs->dpms)
				funcs->dpms(encoder, DRM_MODE_DPMS_OFF);
		}

		drm_atomic_bridge_post_disable(encoder->bridge, old_state);
	}

	for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) {
		const struct drm_crtc_helper_funcs *funcs;
		int ret;

		/* Shut down everything that needs a full modeset. */
		if (!drm_atomic_crtc_needs_modeset(new_crtc_state))
			continue;

		if (!crtc_needs_disable(old_crtc_state, new_crtc_state))
			continue;

		funcs = crtc->helper_private;

		DRM_DEBUG_ATOMIC("disabling [CRTC:%d:%s]\n",
				 crtc->base.id, crtc->name);


		/* Right function depends upon target state. */
		if (new_crtc_state->enable && funcs->prepare)
			funcs->prepare(crtc);
		else if (funcs->atomic_disable)
			funcs->atomic_disable(crtc, old_crtc_state);
		else if (funcs->disable)
			funcs->disable(crtc);
		else if (funcs->dpms)
			funcs->dpms(crtc, DRM_MODE_DPMS_OFF);

		if (!(dev->irq_enabled && dev->num_crtcs))
			continue;

		ret = drm_crtc_vblank_get(crtc);
		WARN_ONCE(ret != -EINVAL, "driver forgot to call drm_crtc_vblank_off()\n");
		if (ret == 0)
			drm_crtc_vblank_put(crtc);
	}
}

/**
 * drm_atomic_helper_update_legacy_modeset_state - update legacy modeset state
 * @dev: DRM device
 * @old_state: atomic state object with old state structures
 *
 * This function updates all the various legacy modeset state pointers in
 * connectors, encoders and crtcs. It also updates the timestamping constants
 * used for precise vblank timestamps by calling
 * drm_calc_timestamping_constants().
 *
 * Drivers can use this for building their own atomic commit if they don't have
 * a pure helper-based modeset implementation.
 *
 * Since these updates are not synchronized with lockings, only code paths
 * called from &drm_mode_config_helper_funcs.atomic_commit_tail can look at the
 * legacy state filled out by this helper. Defacto this means this helper and
 * the legacy state pointers are only really useful for transitioning an
 * existing driver to the atomic world.
 */
void
drm_atomic_helper_update_legacy_modeset_state(struct drm_device *dev,
					      struct drm_atomic_state *old_state)
{
	struct drm_connector *connector;
	struct drm_connector_state *old_conn_state, *new_conn_state;
	struct drm_crtc *crtc;
	struct drm_crtc_state *new_crtc_state;
	int i;

	/* clear out existing links and update dpms */
	for_each_oldnew_connector_in_state(old_state, connector, old_conn_state, new_conn_state, i) {
		if (connector->encoder) {
			WARN_ON(!connector->encoder->crtc);

			connector->encoder->crtc = NULL;
			connector->encoder = NULL;
		}

		crtc = new_conn_state->crtc;
		if ((!crtc && old_conn_state->crtc) ||
		    (crtc && drm_atomic_crtc_needs_modeset(crtc->state))) {
			int mode = DRM_MODE_DPMS_OFF;

			if (crtc && crtc->state->active)
				mode = DRM_MODE_DPMS_ON;

			connector->dpms = mode;
		}
	}

	/* set new links */
	for_each_new_connector_in_state(old_state, connector, new_conn_state, i) {
		if (!new_conn_state->crtc)
			continue;

		if (WARN_ON(!new_conn_state->best_encoder))
			continue;

		connector->encoder = new_conn_state->best_encoder;
		connector->encoder->crtc = new_conn_state->crtc;
	}

	/* set legacy state in the crtc structure */
	for_each_new_crtc_in_state(old_state, crtc, new_crtc_state, i) {
		struct drm_plane *primary = crtc->primary;
		struct drm_plane_state *new_plane_state;

		crtc->mode = new_crtc_state->mode;
		crtc->enabled = new_crtc_state->enable;

		new_plane_state =
			drm_atomic_get_new_plane_state(old_state, primary);

		if (new_plane_state && new_plane_state->crtc == crtc) {
			crtc->x = new_plane_state->src_x >> 16;
			crtc->y = new_plane_state->src_y >> 16;
		}

		if (new_crtc_state->enable)
			drm_calc_timestamping_constants(crtc,
							&new_crtc_state->adjusted_mode);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_update_legacy_modeset_state);

static void
crtc_set_mode(struct drm_device *dev, struct drm_atomic_state *old_state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *new_crtc_state;
	struct drm_connector *connector;
	struct drm_connector_state *new_conn_state;
	int i;

	for_each_new_crtc_in_state(old_state, crtc, new_crtc_state, i) {
		const struct drm_crtc_helper_funcs *funcs;

		if (!new_crtc_state->mode_changed)
			continue;

		funcs = crtc->helper_private;

		if (new_crtc_state->enable && funcs->mode_set_nofb) {
			DRM_DEBUG_ATOMIC("modeset on [CRTC:%d:%s]\n",
					 crtc->base.id, crtc->name);

			funcs->mode_set_nofb(crtc);
		}
	}

	for_each_new_connector_in_state(old_state, connector, new_conn_state, i) {
		const struct drm_encoder_helper_funcs *funcs;
		struct drm_encoder *encoder;
		struct drm_display_mode *mode, *adjusted_mode;

		if (!new_conn_state->best_encoder)
			continue;

		encoder = new_conn_state->best_encoder;
		funcs = encoder->helper_private;
		new_crtc_state = new_conn_state->crtc->state;
		mode = &new_crtc_state->mode;
		adjusted_mode = &new_crtc_state->adjusted_mode;

		if (!new_crtc_state->mode_changed)
			continue;

		DRM_DEBUG_ATOMIC("modeset on [ENCODER:%d:%s]\n",
				 encoder->base.id, encoder->name);

		/*
		 * Each encoder has at most one connector (since we always steal
		 * it away), so we won't call mode_set hooks twice.
		 */
		if (funcs && funcs->atomic_mode_set) {
			funcs->atomic_mode_set(encoder, new_crtc_state,
					       new_conn_state);
		} else if (funcs && funcs->mode_set) {
			funcs->mode_set(encoder, mode, adjusted_mode);
		}

		drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
	}
}

/**
 * drm_atomic_helper_commit_modeset_disables - modeset commit to disable outputs
 * @dev: DRM device
 * @old_state: atomic state object with old state structures
 *
 * This function shuts down all the outputs that need to be shut down and
 * prepares them (if required) with the new mode.
 *
 * For compatibility with legacy crtc helpers this should be called before
 * drm_atomic_helper_commit_planes(), which is what the default commit function
 * does. But drivers with different needs can group the modeset commits together
 * and do the plane commits at the end. This is useful for drivers doing runtime
 * PM since planes updates then only happen when the CRTC is actually enabled.
 */
void drm_atomic_helper_commit_modeset_disables(struct drm_device *dev,
					       struct drm_atomic_state *old_state)
{
	disable_outputs(dev, old_state);

	drm_atomic_helper_update_legacy_modeset_state(dev, old_state);

	crtc_set_mode(dev, old_state);
}
EXPORT_SYMBOL(drm_atomic_helper_commit_modeset_disables);

static void drm_atomic_helper_commit_writebacks(struct drm_device *dev,
						struct drm_atomic_state *old_state)
{
	struct drm_connector *connector;
	struct drm_connector_state *new_conn_state;
	int i;

	for_each_new_connector_in_state(old_state, connector, new_conn_state, i) {
		const struct drm_connector_helper_funcs *funcs;

		funcs = connector->helper_private;
		if (!funcs->atomic_commit)
			continue;

		if (new_conn_state->writeback_job && new_conn_state->writeback_job->fb) {
			WARN_ON(connector->connector_type != DRM_MODE_CONNECTOR_WRITEBACK);
			funcs->atomic_commit(connector, new_conn_state);
		}
	}
}

/**
 * drm_atomic_helper_commit_modeset_enables - modeset commit to enable outputs
 * @dev: DRM device
 * @old_state: atomic state object with old state structures
 *
 * This function enables all the outputs with the new configuration which had to
 * be turned off for the update.
 *
 * For compatibility with legacy crtc helpers this should be called after
 * drm_atomic_helper_commit_planes(), which is what the default commit function
 * does. But drivers with different needs can group the modeset commits together
 * and do the plane commits at the end. This is useful for drivers doing runtime
 * PM since planes updates then only happen when the CRTC is actually enabled.
 */
void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev,
					      struct drm_atomic_state *old_state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state;
	struct drm_crtc_state *new_crtc_state;
	struct drm_connector *connector;
	struct drm_connector_state *new_conn_state;
	int i;

	for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) {
		const struct drm_crtc_helper_funcs *funcs;

		/* Need to filter out CRTCs where only planes change. */
		if (!drm_atomic_crtc_needs_modeset(new_crtc_state))
			continue;

		if (!new_crtc_state->active)
			continue;

		funcs = crtc->helper_private;

		if (new_crtc_state->enable) {
			DRM_DEBUG_ATOMIC("enabling [CRTC:%d:%s]\n",
					 crtc->base.id, crtc->name);
			if (funcs->atomic_enable)
				funcs->atomic_enable(crtc, old_crtc_state);
			else if (funcs->commit)
				funcs->commit(crtc);
		}
	}

	for_each_new_connector_in_state(old_state, connector, new_conn_state, i) {
		const struct drm_encoder_helper_funcs *funcs;
		struct drm_encoder *encoder;

		if (!new_conn_state->best_encoder)
			continue;

		if (!new_conn_state->crtc->state->active ||
		    !drm_atomic_crtc_needs_modeset(new_conn_state->crtc->state))
			continue;

		encoder = new_conn_state->best_encoder;
		funcs = encoder->helper_private;

		DRM_DEBUG_ATOMIC("enabling [ENCODER:%d:%s]\n",
				 encoder->base.id, encoder->name);

		/*
		 * Each encoder has at most one connector (since we always steal
		 * it away), so we won't call enable hooks twice.
		 */
		drm_atomic_bridge_pre_enable(encoder->bridge, old_state);

		if (funcs) {
			if (funcs->atomic_enable)
				funcs->atomic_enable(encoder, old_state);
			else if (funcs->enable)
				funcs->enable(encoder);
			else if (funcs->commit)
				funcs->commit(encoder);
		}

		drm_atomic_bridge_enable(encoder->bridge, old_state);
	}

	drm_atomic_helper_commit_writebacks(dev, old_state);
}
EXPORT_SYMBOL(drm_atomic_helper_commit_modeset_enables);

/**
 * drm_atomic_helper_wait_for_fences - wait for fences stashed in plane state
 * @dev: DRM device
 * @state: atomic state object with old state structures
 * @pre_swap: If true, do an interruptible wait, and @state is the new state.
 * 	Otherwise @state is the old state.
 *
 * For implicit sync, driver should fish the exclusive fence out from the
 * incoming fb's and stash it in the drm_plane_state.  This is called after
 * drm_atomic_helper_swap_state() so it uses the current plane state (and
 * just uses the atomic state to find the changed planes)
 *
 * Note that @pre_swap is needed since the point where we block for fences moves
 * around depending upon whether an atomic commit is blocking or
 * non-blocking. For non-blocking commit all waiting needs to happen after
 * drm_atomic_helper_swap_state() is called, but for blocking commits we want
 * to wait **before** we do anything that can't be easily rolled back. That is
 * before we call drm_atomic_helper_swap_state().
 *
 * Returns zero if success or < 0 if dma_fence_wait() fails.
 */
int drm_atomic_helper_wait_for_fences(struct drm_device *dev,
				      struct drm_atomic_state *state,
				      bool pre_swap)
{
	struct drm_plane *plane;
	struct drm_plane_state *new_plane_state;
	int i, ret;

	for_each_new_plane_in_state(state, plane, new_plane_state, i) {
		if (!new_plane_state->fence)
			continue;

		WARN_ON(!new_plane_state->fb);

		/*
		 * If waiting for fences pre-swap (ie: nonblock), userspace can
		 * still interrupt the operation. Instead of blocking until the
		 * timer expires, make the wait interruptible.
		 */
		ret = dma_fence_wait(new_plane_state->fence, pre_swap);
		if (ret)
			return ret;

		dma_fence_put(new_plane_state->fence);
		new_plane_state->fence = NULL;
	}

	return 0;
}
EXPORT_SYMBOL(drm_atomic_helper_wait_for_fences);

/**
 * drm_atomic_helper_wait_for_vblanks - wait for vblank on crtcs
 * @dev: DRM device
 * @old_state: atomic state object with old state structures
 *
 * Helper to, after atomic commit, wait for vblanks on all effected
 * crtcs (ie. before cleaning up old framebuffers using
 * drm_atomic_helper_cleanup_planes()). It will only wait on CRTCs where the
 * framebuffers have actually changed to optimize for the legacy cursor and
 * plane update use-case.
 *
 * Drivers using the nonblocking commit tracking support initialized by calling
 * drm_atomic_helper_setup_commit() should look at
 * drm_atomic_helper_wait_for_flip_done() as an alternative.
 */
void
drm_atomic_helper_wait_for_vblanks(struct drm_device *dev,
		struct drm_atomic_state *old_state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	int i, ret;
	unsigned crtc_mask = 0;

	 /*
	  * Legacy cursor ioctls are completely unsynced, and userspace
	  * relies on that (by doing tons of cursor updates).
	  */
	if (old_state->legacy_cursor_update)
		return;

	for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) {
		if (!new_crtc_state->active)
			continue;

		ret = drm_crtc_vblank_get(crtc);
		if (ret != 0)
			continue;

		crtc_mask |= drm_crtc_mask(crtc);
		old_state->crtcs[i].last_vblank_count = drm_crtc_vblank_count(crtc);
	}

	for_each_old_crtc_in_state(old_state, crtc, old_crtc_state, i) {
		if (!(crtc_mask & drm_crtc_mask(crtc)))
			continue;

		ret = wait_event_timeout(dev->vblank[i].queue,
				old_state->crtcs[i].last_vblank_count !=
					drm_crtc_vblank_count(crtc),
				msecs_to_jiffies(100));

		WARN(!ret, "[CRTC:%d:%s] vblank wait timed out\n",
		     crtc->base.id, crtc->name);

		drm_crtc_vblank_put(crtc);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_wait_for_vblanks);

/**
 * drm_atomic_helper_wait_for_flip_done - wait for all page flips to be done
 * @dev: DRM device
 * @old_state: atomic state object with old state structures
 *
 * Helper to, after atomic commit, wait for page flips on all effected
 * crtcs (ie. before cleaning up old framebuffers using
 * drm_atomic_helper_cleanup_planes()). Compared to
 * drm_atomic_helper_wait_for_vblanks() this waits for the completion of on all
 * CRTCs, assuming that cursors-only updates are signalling their completion
 * immediately (or using a different path).
 *
 * This requires that drivers use the nonblocking commit tracking support
 * initialized using drm_atomic_helper_setup_commit().
 */
void drm_atomic_helper_wait_for_flip_done(struct drm_device *dev,
					  struct drm_atomic_state *old_state)
{
	struct drm_crtc *crtc;
	int i;

	for (i = 0; i < dev->mode_config.num_crtc; i++) {
		struct drm_crtc_commit *commit = old_state->crtcs[i].commit;
		int ret;

		crtc = old_state->crtcs[i].ptr;

		if (!crtc || !commit)
			continue;

		ret = wait_for_completion_timeout(&commit->flip_done, 10 * HZ);
		if (ret == 0)
			DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n",
				  crtc->base.id, crtc->name);
	}

	if (old_state->fake_commit)
		complete_all(&old_state->fake_commit->flip_done);
}
EXPORT_SYMBOL(drm_atomic_helper_wait_for_flip_done);

/**
 * drm_atomic_helper_commit_tail - commit atomic update to hardware
 * @old_state: atomic state object with old state structures
 *
 * This is the default implementation for the
 * &drm_mode_config_helper_funcs.atomic_commit_tail hook, for drivers
 * that do not support runtime_pm or do not need the CRTC to be
 * enabled to perform a commit. Otherwise, see
 * drm_atomic_helper_commit_tail_rpm().
 *
 * Note that the default ordering of how the various stages are called is to
 * match the legacy modeset helper library closest.
 */
void drm_atomic_helper_commit_tail(struct drm_atomic_state *old_state)
{
	struct drm_device *dev = old_state->dev;

	drm_atomic_helper_commit_modeset_disables(dev, old_state);

	drm_atomic_helper_commit_planes(dev, old_state, 0);

	drm_atomic_helper_commit_modeset_enables(dev, old_state);

	drm_atomic_helper_fake_vblank(old_state);

	drm_atomic_helper_commit_hw_done(old_state);

	drm_atomic_helper_wait_for_vblanks(dev, old_state);

	drm_atomic_helper_cleanup_planes(dev, old_state);
}
EXPORT_SYMBOL(drm_atomic_helper_commit_tail);

/**
 * drm_atomic_helper_commit_tail_rpm - commit atomic update to hardware
 * @old_state: new modeset state to be committed
 *
 * This is an alternative implementation for the
 * &drm_mode_config_helper_funcs.atomic_commit_tail hook, for drivers
 * that support runtime_pm or need the CRTC to be enabled to perform a
 * commit. Otherwise, one should use the default implementation
 * drm_atomic_helper_commit_tail().
 */
void drm_atomic_helper_commit_tail_rpm(struct drm_atomic_state *old_state)
{
	struct drm_device *dev = old_state->dev;

	drm_atomic_helper_commit_modeset_disables(dev, old_state);

	drm_atomic_helper_commit_modeset_enables(dev, old_state);

	drm_atomic_helper_commit_planes(dev, old_state,
					DRM_PLANE_COMMIT_ACTIVE_ONLY);

	drm_atomic_helper_fake_vblank(old_state);

	drm_atomic_helper_commit_hw_done(old_state);

	drm_atomic_helper_wait_for_vblanks(dev, old_state);

	drm_atomic_helper_cleanup_planes(dev, old_state);
}
EXPORT_SYMBOL(drm_atomic_helper_commit_tail_rpm);

static void commit_tail(struct drm_atomic_state *old_state)
{
	struct drm_device *dev = old_state->dev;
	const struct drm_mode_config_helper_funcs *funcs;
	ktime_t start;
	s64 commit_time_ms;

	funcs = dev->mode_config.helper_private;

	/*
	 * We're measuring the _entire_ commit, so the time will vary depending
	 * on how many fences and objects are involved. For the purposes of self
	 * refresh, this is desirable since it'll give us an idea of how
	 * congested things are. This will inform our decision on how often we
	 * should enter self refresh after idle.
	 *
	 * These times will be averaged out in the self refresh helpers to avoid
	 * overreacting over one outlier frame
	 */
	start = ktime_get();

	drm_atomic_helper_wait_for_fences(dev, old_state, false);

	drm_atomic_helper_wait_for_dependencies(old_state);

	if (funcs && funcs->atomic_commit_tail)
		funcs->atomic_commit_tail(old_state);
	else
		drm_atomic_helper_commit_tail(old_state);

	commit_time_ms = ktime_ms_delta(ktime_get(), start);
	if (commit_time_ms > 0)
		drm_self_refresh_helper_update_avg_times(old_state,
						 (unsigned long)commit_time_ms);

	drm_atomic_helper_commit_cleanup_done(old_state);

	drm_atomic_state_put(old_state);
}

static void commit_work(struct work_struct *work)
{
	struct drm_atomic_state *state = container_of(work,
						      struct drm_atomic_state,
						      commit_work);
	commit_tail(state);
}

/**
 * drm_atomic_helper_async_check - check if state can be commited asynchronously
 * @dev: DRM device
 * @state: the driver state object
 *
 * This helper will check if it is possible to commit the state asynchronously.
 * Async commits are not supposed to swap the states like normal sync commits
 * but just do in-place changes on the current state.
 *
 * It will return 0 if the commit can happen in an asynchronous fashion or error
 * if not. Note that error just mean it can't be commited asynchronously, if it
 * fails the commit should be treated like a normal synchronous commit.
 */
int drm_atomic_helper_async_check(struct drm_device *dev,
				   struct drm_atomic_state *state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *crtc_state;
	struct drm_plane *plane = NULL;
	struct drm_plane_state *old_plane_state = NULL;
	struct drm_plane_state *new_plane_state = NULL;
	const struct drm_plane_helper_funcs *funcs;
	int i, n_planes = 0;

	for_each_new_crtc_in_state(state, crtc, crtc_state, i) {
		if (drm_atomic_crtc_needs_modeset(crtc_state))
			return -EINVAL;
	}

	for_each_oldnew_plane_in_state(state, plane, old_plane_state, new_plane_state, i)
		n_planes++;

	/* FIXME: we support only single plane updates for now */
	if (n_planes != 1)
		return -EINVAL;

	if (!new_plane_state->crtc ||
	    old_plane_state->crtc != new_plane_state->crtc)
		return -EINVAL;

	funcs = plane->helper_private;
	if (!funcs->atomic_async_update)
		return -EINVAL;

	if (new_plane_state->fence)
		return -EINVAL;

	/*
	 * Don't do an async update if there is an outstanding commit modifying
	 * the plane.  This prevents our async update's changes from getting
	 * overridden by a previous synchronous update's state.
	 */
	if (old_plane_state->commit &&
	    !try_wait_for_completion(&old_plane_state->commit->hw_done))
		return -EBUSY;

	return funcs->atomic_async_check(plane, new_plane_state);
}
EXPORT_SYMBOL(drm_atomic_helper_async_check);

/**
 * drm_atomic_helper_async_commit - commit state asynchronously
 * @dev: DRM device
 * @state: the driver state object
 *
 * This function commits a state asynchronously, i.e., not vblank
 * synchronized. It should be used on a state only when
 * drm_atomic_async_check() succeeds. Async commits are not supposed to swap
 * the states like normal sync commits, but just do in-place changes on the
 * current state.
 *
 * TODO: Implement full swap instead of doing in-place changes.
 */
void drm_atomic_helper_async_commit(struct drm_device *dev,
				    struct drm_atomic_state *state)
{
	struct drm_plane *plane;
	struct drm_plane_state *plane_state;
	const struct drm_plane_helper_funcs *funcs;
	int i;

	for_each_new_plane_in_state(state, plane, plane_state, i) {
		struct drm_framebuffer *new_fb = plane_state->fb;
		struct drm_framebuffer *old_fb = plane->state->fb;

		funcs = plane->helper_private;
		funcs->atomic_async_update(plane, plane_state);

		/*
		 * ->atomic_async_update() is supposed to update the
		 * plane->state in-place, make sure at least common
		 * properties have been properly updated.
		 */
		WARN_ON_ONCE(plane->state->fb != new_fb);
		WARN_ON_ONCE(plane->state->crtc_x != plane_state->crtc_x);
		WARN_ON_ONCE(plane->state->crtc_y != plane_state->crtc_y);
		WARN_ON_ONCE(plane->state->src_x != plane_state->src_x);
		WARN_ON_ONCE(plane->state->src_y != plane_state->src_y);

		/*
		 * Make sure the FBs have been swapped so that cleanups in the
		 * new_state performs a cleanup in the old FB.
		 */
		WARN_ON_ONCE(plane_state->fb != old_fb);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_async_commit);

/**
 * drm_atomic_helper_commit - commit validated state object
 * @dev: DRM device
 * @state: the driver state object
 * @nonblock: whether nonblocking behavior is requested.
 *
 * This function commits a with drm_atomic_helper_check() pre-validated state
 * object. This can still fail when e.g. the framebuffer reservation fails. This
 * function implements nonblocking commits, using
 * drm_atomic_helper_setup_commit() and related functions.
 *
 * Committing the actual hardware state is done through the
 * &drm_mode_config_helper_funcs.atomic_commit_tail callback, or its default
 * implementation drm_atomic_helper_commit_tail().
 *
 * RETURNS:
 * Zero for success or -errno.
 */
int drm_atomic_helper_commit(struct drm_device *dev,
			     struct drm_atomic_state *state,
			     bool nonblock)
{
	int ret;

	if (state->async_update) {
		ret = drm_atomic_helper_prepare_planes(dev, state);
		if (ret)
			return ret;

		drm_atomic_helper_async_commit(dev, state);
		drm_atomic_helper_cleanup_planes(dev, state);

		return 0;
	}

	ret = drm_atomic_helper_setup_commit(state, nonblock);
	if (ret)
		return ret;

	INIT_WORK(&state->commit_work, commit_work);

	ret = drm_atomic_helper_prepare_planes(dev, state);
	if (ret)
		return ret;

	if (!nonblock) {
		ret = drm_atomic_helper_wait_for_fences(dev, state, true);
		if (ret)
			goto err;
	}

	/*
	 * This is the point of no return - everything below never fails except
	 * when the hw goes bonghits. Which means we can commit the new state on
	 * the software side now.
	 */

	ret = drm_atomic_helper_swap_state(state, true);
	if (ret)
		goto err;

	/*
	 * Everything below can be run asynchronously without the need to grab
	 * any modeset locks at all under one condition: It must be guaranteed
	 * that the asynchronous work has either been cancelled (if the driver
	 * supports it, which at least requires that the framebuffers get
	 * cleaned up with drm_atomic_helper_cleanup_planes()) or completed
	 * before the new state gets committed on the software side with
	 * drm_atomic_helper_swap_state().
	 *
	 * This scheme allows new atomic state updates to be prepared and
	 * checked in parallel to the asynchronous completion of the previous
	 * update. Which is important since compositors need to figure out the
	 * composition of the next frame right after having submitted the
	 * current layout.
	 *
	 * NOTE: Commit work has multiple phases, first hardware commit, then
	 * cleanup. We want them to overlap, hence need system_unbound_wq to
	 * make sure work items don't artificially stall on each another.
	 */

	drm_atomic_state_get(state);
	if (nonblock)
		queue_work(system_unbound_wq, &state->commit_work);
	else
		commit_tail(state);

	return 0;

err:
	drm_atomic_helper_cleanup_planes(dev, state);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_commit);

/**
 * DOC: implementing nonblocking commit
 *
 * Nonblocking atomic commits have to be implemented in the following sequence:
 *
 * 1. Run drm_atomic_helper_prepare_planes() first. This is the only function
 * which commit needs to call which can fail, so we want to run it first and
 * synchronously.
 *
 * 2. Synchronize with any outstanding nonblocking commit worker threads which
 * might be affected the new state update. This can be done by either cancelling
 * or flushing the work items, depending upon whether the driver can deal with
 * cancelled updates. Note that it is important to ensure that the framebuffer
 * cleanup is still done when cancelling.
 *
 * Asynchronous workers need to have sufficient parallelism to be able to run
 * different atomic commits on different CRTCs in parallel. The simplest way to
 * achieve this is by running them on the &system_unbound_wq work queue. Note
 * that drivers are not required to split up atomic commits and run an
 * individual commit in parallel - userspace is supposed to do that if it cares.
 * But it might be beneficial to do that for modesets, since those necessarily
 * must be done as one global operation, and enabling or disabling a CRTC can
 * take a long time. But even that is not required.
 *
 * 3. The software state is updated synchronously with
 * drm_atomic_helper_swap_state(). Doing this under the protection of all modeset
 * locks means concurrent callers never see inconsistent state. And doing this
 * while it's guaranteed that no relevant nonblocking worker runs means that
 * nonblocking workers do not need grab any locks. Actually they must not grab
 * locks, for otherwise the work flushing will deadlock.
 *
 * 4. Schedule a work item to do all subsequent steps, using the split-out
 * commit helpers: a) pre-plane commit b) plane commit c) post-plane commit and
 * then cleaning up the framebuffers after the old framebuffer is no longer
 * being displayed.
 *
 * The above scheme is implemented in the atomic helper libraries in
 * drm_atomic_helper_commit() using a bunch of helper functions. See
 * drm_atomic_helper_setup_commit() for a starting point.
 */

static int stall_checks(struct drm_crtc *crtc, bool nonblock)
{
	struct drm_crtc_commit *commit, *stall_commit = NULL;
	bool completed = true;
	int i;
	long ret = 0;

	spin_lock(&crtc->commit_lock);
	i = 0;
	list_for_each_entry(commit, &crtc->commit_list, commit_entry) {
		if (i == 0) {
			completed = try_wait_for_completion(&commit->flip_done);
			/* Userspace is not allowed to get ahead of the previous
			 * commit with nonblocking ones. */
			if (!completed && nonblock) {
				spin_unlock(&crtc->commit_lock);
				return -EBUSY;
			}
		} else if (i == 1) {
			stall_commit = drm_crtc_commit_get(commit);
			break;
		}

		i++;
	}
	spin_unlock(&crtc->commit_lock);

	if (!stall_commit)
		return 0;

	/* We don't want to let commits get ahead of cleanup work too much,
	 * stalling on 2nd previous commit means triple-buffer won't ever stall.
	 */
	ret = wait_for_completion_interruptible_timeout(&stall_commit->cleanup_done,
							10*HZ);
	if (ret == 0)
		DRM_ERROR("[CRTC:%d:%s] cleanup_done timed out\n",
			  crtc->base.id, crtc->name);

	drm_crtc_commit_put(stall_commit);

	return ret < 0 ? ret : 0;
}

static void release_crtc_commit(struct completion *completion)
{
	struct drm_crtc_commit *commit = container_of(completion,
						      typeof(*commit),
						      flip_done);

	drm_crtc_commit_put(commit);
}

static void init_commit(struct drm_crtc_commit *commit, struct drm_crtc *crtc)
{
	init_completion(&commit->flip_done);
	init_completion(&commit->hw_done);
	init_completion(&commit->cleanup_done);
	INIT_LIST_HEAD(&commit->commit_entry);
	kref_init(&commit->ref);
	commit->crtc = crtc;
}

static struct drm_crtc_commit *
crtc_or_fake_commit(struct drm_atomic_state *state, struct drm_crtc *crtc)
{
	if (crtc) {
		struct drm_crtc_state *new_crtc_state;

		new_crtc_state = drm_atomic_get_new_crtc_state(state, crtc);

		return new_crtc_state->commit;
	}

	if (!state->fake_commit) {
		state->fake_commit = kzalloc(sizeof(*state->fake_commit), GFP_KERNEL);
		if (!state->fake_commit)
			return NULL;

		init_commit(state->fake_commit, NULL);
	}

	return state->fake_commit;
}

/**
 * drm_atomic_helper_setup_commit - setup possibly nonblocking commit
 * @state: new modeset state to be committed
 * @nonblock: whether nonblocking behavior is requested.
 *
 * This function prepares @state to be used by the atomic helper's support for
 * nonblocking commits. Drivers using the nonblocking commit infrastructure
 * should always call this function from their
 * &drm_mode_config_funcs.atomic_commit hook.
 *
 * To be able to use this support drivers need to use a few more helper
 * functions. drm_atomic_helper_wait_for_dependencies() must be called before
 * actually committing the hardware state, and for nonblocking commits this call
 * must be placed in the async worker. See also drm_atomic_helper_swap_state()
 * and its stall parameter, for when a driver's commit hooks look at the
 * &drm_crtc.state, &drm_plane.state or &drm_connector.state pointer directly.
 *
 * Completion of the hardware commit step must be signalled using
 * drm_atomic_helper_commit_hw_done(). After this step the driver is not allowed
 * to read or change any permanent software or hardware modeset state. The only
 * exception is state protected by other means than &drm_modeset_lock locks.
 * Only the free standing @state with pointers to the old state structures can
 * be inspected, e.g. to clean up old buffers using
 * drm_atomic_helper_cleanup_planes().
 *
 * At the very end, before cleaning up @state drivers must call
 * drm_atomic_helper_commit_cleanup_done().
 *
 * This is all implemented by in drm_atomic_helper_commit(), giving drivers a
 * complete and easy-to-use default implementation of the atomic_commit() hook.
 *
 * The tracking of asynchronously executed and still pending commits is done
 * using the core structure &drm_crtc_commit.
 *
 * By default there's no need to clean up resources allocated by this function
 * explicitly: drm_atomic_state_default_clear() will take care of that
 * automatically.
 *
 * Returns:
 *
 * 0 on success. -EBUSY when userspace schedules nonblocking commits too fast,
 * -ENOMEM on allocation failures and -EINTR when a signal is pending.
 */
int drm_atomic_helper_setup_commit(struct drm_atomic_state *state,
				   bool nonblock)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	struct drm_connector *conn;
	struct drm_connector_state *old_conn_state, *new_conn_state;
	struct drm_plane *plane;
	struct drm_plane_state *old_plane_state, *new_plane_state;
	struct drm_crtc_commit *commit;
	int i, ret;

	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
		commit = kzalloc(sizeof(*commit), GFP_KERNEL);
		if (!commit)
			return -ENOMEM;

		init_commit(commit, crtc);

		new_crtc_state->commit = commit;

		ret = stall_checks(crtc, nonblock);
		if (ret)
			return ret;

		/* Drivers only send out events when at least either current or
		 * new CRTC state is active. Complete right away if everything
		 * stays off. */
		if (!old_crtc_state->active && !new_crtc_state->active) {
			complete_all(&commit->flip_done);
			continue;
		}

		/* Legacy cursor updates are fully unsynced. */
		if (state->legacy_cursor_update) {
			complete_all(&commit->flip_done);
			continue;
		}

		if (!new_crtc_state->event) {
			commit->event = kzalloc(sizeof(*commit->event),
						GFP_KERNEL);
			if (!commit->event)
				return -ENOMEM;

			new_crtc_state->event = commit->event;
		}

		new_crtc_state->event->base.completion = &commit->flip_done;
		new_crtc_state->event->base.completion_release = release_crtc_commit;
		drm_crtc_commit_get(commit);

		commit->abort_completion = true;

		state->crtcs[i].commit = commit;
		drm_crtc_commit_get(commit);
	}

	for_each_oldnew_connector_in_state(state, conn, old_conn_state, new_conn_state, i) {
		/* Userspace is not allowed to get ahead of the previous
		 * commit with nonblocking ones. */
		if (nonblock && old_conn_state->commit &&
		    !try_wait_for_completion(&old_conn_state->commit->flip_done))
			return -EBUSY;

		/* Always track connectors explicitly for e.g. link retraining. */
		commit = crtc_or_fake_commit(state, new_conn_state->crtc ?: old_conn_state->crtc);
		if (!commit)
			return -ENOMEM;

		new_conn_state->commit = drm_crtc_commit_get(commit);
	}

	for_each_oldnew_plane_in_state(state, plane, old_plane_state, new_plane_state, i) {
		/* Userspace is not allowed to get ahead of the previous
		 * commit with nonblocking ones. */
		if (nonblock && old_plane_state->commit &&
		    !try_wait_for_completion(&old_plane_state->commit->flip_done))
			return -EBUSY;

		/* Always track planes explicitly for async pageflip support. */
		commit = crtc_or_fake_commit(state, new_plane_state->crtc ?: old_plane_state->crtc);
		if (!commit)
			return -ENOMEM;

		new_plane_state->commit = drm_crtc_commit_get(commit);
	}

	return 0;
}
EXPORT_SYMBOL(drm_atomic_helper_setup_commit);

/**
 * drm_atomic_helper_wait_for_dependencies - wait for required preceeding commits
 * @old_state: atomic state object with old state structures
 *
 * This function waits for all preceeding commits that touch the same CRTC as
 * @old_state to both be committed to the hardware (as signalled by
 * drm_atomic_helper_commit_hw_done) and executed by the hardware (as signalled
 * by calling drm_crtc_send_vblank_event() on the &drm_crtc_state.event).
 *
 * This is part of the atomic helper support for nonblocking commits, see
 * drm_atomic_helper_setup_commit() for an overview.
 */
void drm_atomic_helper_wait_for_dependencies(struct drm_atomic_state *old_state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state;
	struct drm_plane *plane;
	struct drm_plane_state *old_plane_state;
	struct drm_connector *conn;
	struct drm_connector_state *old_conn_state;
	struct drm_crtc_commit *commit;
	int i;
	long ret;

	for_each_old_crtc_in_state(old_state, crtc, old_crtc_state, i) {
		commit = old_crtc_state->commit;

		if (!commit)
			continue;

		ret = wait_for_completion_timeout(&commit->hw_done,
						  10*HZ);
		if (ret == 0)
			DRM_ERROR("[CRTC:%d:%s] hw_done timed out\n",
				  crtc->base.id, crtc->name);

		/* Currently no support for overwriting flips, hence
		 * stall for previous one to execute completely. */
		ret = wait_for_completion_timeout(&commit->flip_done,
						  10*HZ);
		if (ret == 0)
			DRM_ERROR("[CRTC:%d:%s] flip_done timed out\n",
				  crtc->base.id, crtc->name);
	}

	for_each_old_connector_in_state(old_state, conn, old_conn_state, i) {
		commit = old_conn_state->commit;

		if (!commit)
			continue;

		ret = wait_for_completion_timeout(&commit->hw_done,
						  10*HZ);
		if (ret == 0)
			DRM_ERROR("[CONNECTOR:%d:%s] hw_done timed out\n",
				  conn->base.id, conn->name);

		/* Currently no support for overwriting flips, hence
		 * stall for previous one to execute completely. */
		ret = wait_for_completion_timeout(&commit->flip_done,
						  10*HZ);
		if (ret == 0)
			DRM_ERROR("[CONNECTOR:%d:%s] flip_done timed out\n",
				  conn->base.id, conn->name);
	}

	for_each_old_plane_in_state(old_state, plane, old_plane_state, i) {
		commit = old_plane_state->commit;

		if (!commit)
			continue;

		ret = wait_for_completion_timeout(&commit->hw_done,
						  10*HZ);
		if (ret == 0)
			DRM_ERROR("[PLANE:%d:%s] hw_done timed out\n",
				  plane->base.id, plane->name);

		/* Currently no support for overwriting flips, hence
		 * stall for previous one to execute completely. */
		ret = wait_for_completion_timeout(&commit->flip_done,
						  10*HZ);
		if (ret == 0)
			DRM_ERROR("[PLANE:%d:%s] flip_done timed out\n",
				  plane->base.id, plane->name);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_wait_for_dependencies);

/**
 * drm_atomic_helper_fake_vblank - fake VBLANK events if needed
 * @old_state: atomic state object with old state structures
 *
 * This function walks all CRTCs and fake VBLANK events on those with
 * &drm_crtc_state.no_vblank set to true and &drm_crtc_state.event != NULL.
 * The primary use of this function is writeback connectors working in oneshot
 * mode and faking VBLANK events. In this case they only fake the VBLANK event
 * when a job is queued, and any change to the pipeline that does not touch the
 * connector is leading to timeouts when calling
 * drm_atomic_helper_wait_for_vblanks() or
 * drm_atomic_helper_wait_for_flip_done().
 *
 * This is part of the atomic helper support for nonblocking commits, see
 * drm_atomic_helper_setup_commit() for an overview.
 */
void drm_atomic_helper_fake_vblank(struct drm_atomic_state *old_state)
{
	struct drm_crtc_state *new_crtc_state;
	struct drm_crtc *crtc;
	int i;

	for_each_new_crtc_in_state(old_state, crtc, new_crtc_state, i) {
		unsigned long flags;

		if (!new_crtc_state->no_vblank)
			continue;

		spin_lock_irqsave(&old_state->dev->event_lock, flags);
		if (new_crtc_state->event) {
			drm_crtc_send_vblank_event(crtc,
						   new_crtc_state->event);
			new_crtc_state->event = NULL;
		}
		spin_unlock_irqrestore(&old_state->dev->event_lock, flags);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_fake_vblank);

/**
 * drm_atomic_helper_commit_hw_done - setup possible nonblocking commit
 * @old_state: atomic state object with old state structures
 *
 * This function is used to signal completion of the hardware commit step. After
 * this step the driver is not allowed to read or change any permanent software
 * or hardware modeset state. The only exception is state protected by other
 * means than &drm_modeset_lock locks.
 *
 * Drivers should try to postpone any expensive or delayed cleanup work after
 * this function is called.
 *
 * This is part of the atomic helper support for nonblocking commits, see
 * drm_atomic_helper_setup_commit() for an overview.
 */
void drm_atomic_helper_commit_hw_done(struct drm_atomic_state *old_state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	struct drm_crtc_commit *commit;
	int i;

	for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) {
		commit = new_crtc_state->commit;
		if (!commit)
			continue;

		/*
		 * copy new_crtc_state->commit to old_crtc_state->commit,
		 * it's unsafe to touch new_crtc_state after hw_done,
		 * but we still need to do so in cleanup_done().
		 */
		if (old_crtc_state->commit)
			drm_crtc_commit_put(old_crtc_state->commit);

		old_crtc_state->commit = drm_crtc_commit_get(commit);

		/* backend must have consumed any event by now */
		WARN_ON(new_crtc_state->event);
		complete_all(&commit->hw_done);
	}

	if (old_state->fake_commit) {
		complete_all(&old_state->fake_commit->hw_done);
		complete_all(&old_state->fake_commit->flip_done);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_commit_hw_done);

/**
 * drm_atomic_helper_commit_cleanup_done - signal completion of commit
 * @old_state: atomic state object with old state structures
 *
 * This signals completion of the atomic update @old_state, including any
 * cleanup work. If used, it must be called right before calling
 * drm_atomic_state_put().
 *
 * This is part of the atomic helper support for nonblocking commits, see
 * drm_atomic_helper_setup_commit() for an overview.
 */
void drm_atomic_helper_commit_cleanup_done(struct drm_atomic_state *old_state)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state;
	struct drm_crtc_commit *commit;
	int i;

	for_each_old_crtc_in_state(old_state, crtc, old_crtc_state, i) {
		commit = old_crtc_state->commit;
		if (WARN_ON(!commit))
			continue;

		complete_all(&commit->cleanup_done);
		WARN_ON(!try_wait_for_completion(&commit->hw_done));

		spin_lock(&crtc->commit_lock);
		list_del(&commit->commit_entry);
		spin_unlock(&crtc->commit_lock);
	}

	if (old_state->fake_commit) {
		complete_all(&old_state->fake_commit->cleanup_done);
		WARN_ON(!try_wait_for_completion(&old_state->fake_commit->hw_done));
	}
}
EXPORT_SYMBOL(drm_atomic_helper_commit_cleanup_done);

/**
 * drm_atomic_helper_prepare_planes - prepare plane resources before commit
 * @dev: DRM device
 * @state: atomic state object with new state structures
 *
 * This function prepares plane state, specifically framebuffers, for the new
 * configuration, by calling &drm_plane_helper_funcs.prepare_fb. If any failure
 * is encountered this function will call &drm_plane_helper_funcs.cleanup_fb on
 * any already successfully prepared framebuffer.
 *
 * Returns:
 * 0 on success, negative error code on failure.
 */
int drm_atomic_helper_prepare_planes(struct drm_device *dev,
				     struct drm_atomic_state *state)
{
	struct drm_connector *connector;
	struct drm_connector_state *new_conn_state;
	struct drm_plane *plane;
	struct drm_plane_state *new_plane_state;
	int ret, i, j;

	for_each_new_connector_in_state(state, connector, new_conn_state, i) {
		if (!new_conn_state->writeback_job)
			continue;

		ret = drm_writeback_prepare_job(new_conn_state->writeback_job);
		if (ret < 0)
			return ret;
	}

	for_each_new_plane_in_state(state, plane, new_plane_state, i) {
		const struct drm_plane_helper_funcs *funcs;

		funcs = plane->helper_private;

		if (funcs->prepare_fb) {
			ret = funcs->prepare_fb(plane, new_plane_state);
			if (ret)
				goto fail;
		}
	}

	return 0;

fail:
	for_each_new_plane_in_state(state, plane, new_plane_state, j) {
		const struct drm_plane_helper_funcs *funcs;

		if (j >= i)
			continue;

		funcs = plane->helper_private;

		if (funcs->cleanup_fb)
			funcs->cleanup_fb(plane, new_plane_state);
	}

	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_prepare_planes);

static bool plane_crtc_active(const struct drm_plane_state *state)
{
	return state->crtc && state->crtc->state->active;
}

/**
 * drm_atomic_helper_commit_planes - commit plane state
 * @dev: DRM device
 * @old_state: atomic state object with old state structures
 * @flags: flags for committing plane state
 *
 * This function commits the new plane state using the plane and atomic helper
 * functions for planes and crtcs. It assumes that the atomic state has already
 * been pushed into the relevant object state pointers, since this step can no
 * longer fail.
 *
 * It still requires the global state object @old_state to know which planes and
 * crtcs need to be updated though.
 *
 * Note that this function does all plane updates across all CRTCs in one step.
 * If the hardware can't support this approach look at
 * drm_atomic_helper_commit_planes_on_crtc() instead.
 *
 * Plane parameters can be updated by applications while the associated CRTC is
 * disabled. The DRM/KMS core will store the parameters in the plane state,
 * which will be available to the driver when the CRTC is turned on. As a result
 * most drivers don't need to be immediately notified of plane updates for a
 * disabled CRTC.
 *
 * Unless otherwise needed, drivers are advised to set the ACTIVE_ONLY flag in
 * @flags in order not to receive plane update notifications related to a
 * disabled CRTC. This avoids the need to manually ignore plane updates in
 * driver code when the driver and/or hardware can't or just don't need to deal
 * with updates on disabled CRTCs, for example when supporting runtime PM.
 *
 * Drivers may set the NO_DISABLE_AFTER_MODESET flag in @flags if the relevant
 * display controllers require to disable a CRTC's planes when the CRTC is
 * disabled. This function would skip the &drm_plane_helper_funcs.atomic_disable
 * call for a plane if the CRTC of the old plane state needs a modesetting
 * operation. Of course, the drivers need to disable the planes in their CRTC
 * disable callbacks since no one else would do that.
 *
 * The drm_atomic_helper_commit() default implementation doesn't set the
 * ACTIVE_ONLY flag to most closely match the behaviour of the legacy helpers.
 * This should not be copied blindly by drivers.
 */
void drm_atomic_helper_commit_planes(struct drm_device *dev,
				     struct drm_atomic_state *old_state,
				     uint32_t flags)
{
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	struct drm_plane *plane;
	struct drm_plane_state *old_plane_state, *new_plane_state;
	int i;
	bool active_only = flags & DRM_PLANE_COMMIT_ACTIVE_ONLY;
	bool no_disable = flags & DRM_PLANE_COMMIT_NO_DISABLE_AFTER_MODESET;

	for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) {
		const struct drm_crtc_helper_funcs *funcs;

		funcs = crtc->helper_private;

		if (!funcs || !funcs->atomic_begin)
			continue;

		if (active_only && !new_crtc_state->active)
			continue;

		funcs->atomic_begin(crtc, old_crtc_state);
	}

	for_each_oldnew_plane_in_state(old_state, plane, old_plane_state, new_plane_state, i) {
		const struct drm_plane_helper_funcs *funcs;
		bool disabling;

		funcs = plane->helper_private;

		if (!funcs)
			continue;

		disabling = drm_atomic_plane_disabling(old_plane_state,
						       new_plane_state);

		if (active_only) {
			/*
			 * Skip planes related to inactive CRTCs. If the plane
			 * is enabled use the state of the current CRTC. If the
			 * plane is being disabled use the state of the old
			 * CRTC to avoid skipping planes being disabled on an
			 * active CRTC.
			 */
			if (!disabling && !plane_crtc_active(new_plane_state))
				continue;
			if (disabling && !plane_crtc_active(old_plane_state))
				continue;
		}

		/*
		 * Special-case disabling the plane if drivers support it.
		 */
		if (disabling && funcs->atomic_disable) {
			struct drm_crtc_state *crtc_state;

			crtc_state = old_plane_state->crtc->state;

			if (drm_atomic_crtc_needs_modeset(crtc_state) &&
			    no_disable)
				continue;

			funcs->atomic_disable(plane, old_plane_state);
		} else if (new_plane_state->crtc || disabling) {
			funcs->atomic_update(plane, old_plane_state);
		}
	}

	for_each_oldnew_crtc_in_state(old_state, crtc, old_crtc_state, new_crtc_state, i) {
		const struct drm_crtc_helper_funcs *funcs;

		funcs = crtc->helper_private;

		if (!funcs || !funcs->atomic_flush)
			continue;

		if (active_only && !new_crtc_state->active)
			continue;

		funcs->atomic_flush(crtc, old_crtc_state);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_commit_planes);

/**
 * drm_atomic_helper_commit_planes_on_crtc - commit plane state for a crtc
 * @old_crtc_state: atomic state object with the old crtc state
 *
 * This function commits the new plane state using the plane and atomic helper
 * functions for planes on the specific crtc. It assumes that the atomic state
 * has already been pushed into the relevant object state pointers, since this
 * step can no longer fail.
 *
 * This function is useful when plane updates should be done crtc-by-crtc
 * instead of one global step like drm_atomic_helper_commit_planes() does.
 *
 * This function can only be savely used when planes are not allowed to move
 * between different CRTCs because this function doesn't handle inter-CRTC
 * depencies. Callers need to ensure that either no such depencies exist,
 * resolve them through ordering of commit calls or through some other means.
 */
void
drm_atomic_helper_commit_planes_on_crtc(struct drm_crtc_state *old_crtc_state)
{
	const struct drm_crtc_helper_funcs *crtc_funcs;
	struct drm_crtc *crtc = old_crtc_state->crtc;
	struct drm_atomic_state *old_state = old_crtc_state->state;
	struct drm_crtc_state *new_crtc_state =
		drm_atomic_get_new_crtc_state(old_state, crtc);
	struct drm_plane *plane;
	unsigned plane_mask;

	plane_mask = old_crtc_state->plane_mask;
	plane_mask |= new_crtc_state->plane_mask;

	crtc_funcs = crtc->helper_private;
	if (crtc_funcs && crtc_funcs->atomic_begin)
		crtc_funcs->atomic_begin(crtc, old_crtc_state);

	drm_for_each_plane_mask(plane, crtc->dev, plane_mask) {
		struct drm_plane_state *old_plane_state =
			drm_atomic_get_old_plane_state(old_state, plane);
		struct drm_plane_state *new_plane_state =
			drm_atomic_get_new_plane_state(old_state, plane);
		const struct drm_plane_helper_funcs *plane_funcs;

		plane_funcs = plane->helper_private;

		if (!old_plane_state || !plane_funcs)
			continue;

		WARN_ON(new_plane_state->crtc &&
			new_plane_state->crtc != crtc);

		if (drm_atomic_plane_disabling(old_plane_state, new_plane_state) &&
		    plane_funcs->atomic_disable)
			plane_funcs->atomic_disable(plane, old_plane_state);
		else if (new_plane_state->crtc ||
			 drm_atomic_plane_disabling(old_plane_state, new_plane_state))
			plane_funcs->atomic_update(plane, old_plane_state);
	}

	if (crtc_funcs && crtc_funcs->atomic_flush)
		crtc_funcs->atomic_flush(crtc, old_crtc_state);
}
EXPORT_SYMBOL(drm_atomic_helper_commit_planes_on_crtc);

/**
 * drm_atomic_helper_disable_planes_on_crtc - helper to disable CRTC's planes
 * @old_crtc_state: atomic state object with the old CRTC state
 * @atomic: if set, synchronize with CRTC's atomic_begin/flush hooks
 *
 * Disables all planes associated with the given CRTC. This can be
 * used for instance in the CRTC helper atomic_disable callback to disable
 * all planes.
 *
 * If the atomic-parameter is set the function calls the CRTC's
 * atomic_begin hook before and atomic_flush hook after disabling the
 * planes.
 *
 * It is a bug to call this function without having implemented the
 * &drm_plane_helper_funcs.atomic_disable plane hook.
 */
void
drm_atomic_helper_disable_planes_on_crtc(struct drm_crtc_state *old_crtc_state,
					 bool atomic)
{
	struct drm_crtc *crtc = old_crtc_state->crtc;
	const struct drm_crtc_helper_funcs *crtc_funcs =
		crtc->helper_private;
	struct drm_plane *plane;

	if (atomic && crtc_funcs && crtc_funcs->atomic_begin)
		crtc_funcs->atomic_begin(crtc, NULL);

	drm_atomic_crtc_state_for_each_plane(plane, old_crtc_state) {
		const struct drm_plane_helper_funcs *plane_funcs =
			plane->helper_private;

		if (!plane_funcs)
			continue;

		WARN_ON(!plane_funcs->atomic_disable);
		if (plane_funcs->atomic_disable)
			plane_funcs->atomic_disable(plane, NULL);
	}

	if (atomic && crtc_funcs && crtc_funcs->atomic_flush)
		crtc_funcs->atomic_flush(crtc, NULL);
}
EXPORT_SYMBOL(drm_atomic_helper_disable_planes_on_crtc);

/**
 * drm_atomic_helper_cleanup_planes - cleanup plane resources after commit
 * @dev: DRM device
 * @old_state: atomic state object with old state structures
 *
 * This function cleans up plane state, specifically framebuffers, from the old
 * configuration. Hence the old configuration must be perserved in @old_state to
 * be able to call this function.
 *
 * This function must also be called on the new state when the atomic update
 * fails at any point after calling drm_atomic_helper_prepare_planes().
 */
void drm_atomic_helper_cleanup_planes(struct drm_device *dev,
				      struct drm_atomic_state *old_state)
{
	struct drm_plane *plane;
	struct drm_plane_state *old_plane_state, *new_plane_state;
	int i;

	for_each_oldnew_plane_in_state(old_state, plane, old_plane_state, new_plane_state, i) {
		const struct drm_plane_helper_funcs *funcs;
		struct drm_plane_state *plane_state;

		/*
		 * This might be called before swapping when commit is aborted,
		 * in which case we have to cleanup the new state.
		 */
		if (old_plane_state == plane->state)
			plane_state = new_plane_state;
		else
			plane_state = old_plane_state;

		funcs = plane->helper_private;

		if (funcs->cleanup_fb)
			funcs->cleanup_fb(plane, plane_state);
	}
}
EXPORT_SYMBOL(drm_atomic_helper_cleanup_planes);

/**
 * drm_atomic_helper_swap_state - store atomic state into current sw state
 * @state: atomic state
 * @stall: stall for preceeding commits
 *
 * This function stores the atomic state into the current state pointers in all
 * driver objects. It should be called after all failing steps have been done
 * and succeeded, but before the actual hardware state is committed.
 *
 * For cleanup and error recovery the current state for all changed objects will
 * be swapped into @state.
 *
 * With that sequence it fits perfectly into the plane prepare/cleanup sequence:
 *
 * 1. Call drm_atomic_helper_prepare_planes() with the staged atomic state.
 *
 * 2. Do any other steps that might fail.
 *
 * 3. Put the staged state into the current state pointers with this function.
 *
 * 4. Actually commit the hardware state.
 *
 * 5. Call drm_atomic_helper_cleanup_planes() with @state, which since step 3
 * contains the old state. Also do any other cleanup required with that state.
 *
 * @stall must be set when nonblocking commits for this driver directly access
 * the &drm_plane.state, &drm_crtc.state or &drm_connector.state pointer. With
 * the current atomic helpers this is almost always the case, since the helpers
 * don't pass the right state structures to the callbacks.
 *
 * Returns:
 *
 * Returns 0 on success. Can return -ERESTARTSYS when @stall is true and the
 * waiting for the previous commits has been interrupted.
 */
int drm_atomic_helper_swap_state(struct drm_atomic_state *state,
				  bool stall)
{
	int i, ret;
	struct drm_connector *connector;
	struct drm_connector_state *old_conn_state, *new_conn_state;
	struct drm_crtc *crtc;
	struct drm_crtc_state *old_crtc_state, *new_crtc_state;
	struct drm_plane *plane;
	struct drm_plane_state *old_plane_state, *new_plane_state;
	struct drm_crtc_commit *commit;
	struct drm_private_obj *obj;
	struct drm_private_state *old_obj_state, *new_obj_state;

	if (stall) {
		/*
		 * We have to stall for hw_done here before
		 * drm_atomic_helper_wait_for_dependencies() because flip
		 * depth > 1 is not yet supported by all drivers. As long as
		 * obj->state is directly dereferenced anywhere in the drivers
		 * atomic_commit_tail function, then it's unsafe to swap state
		 * before drm_atomic_helper_commit_hw_done() is called.
		 */

		for_each_old_crtc_in_state(state, crtc, old_crtc_state, i) {
			commit = old_crtc_state->commit;

			if (!commit)
				continue;

			ret = wait_for_completion_interruptible(&commit->hw_done);
			if (ret)
				return ret;
		}

		for_each_old_connector_in_state(state, connector, old_conn_state, i) {
			commit = old_conn_state->commit;

			if (!commit)
				continue;

			ret = wait_for_completion_interruptible(&commit->hw_done);
			if (ret)
				return ret;
		}

		for_each_old_plane_in_state(state, plane, old_plane_state, i) {
			commit = old_plane_state->commit;

			if (!commit)
				continue;

			ret = wait_for_completion_interruptible(&commit->hw_done);
			if (ret)
				return ret;
		}
	}

	for_each_oldnew_connector_in_state(state, connector, old_conn_state, new_conn_state, i) {
		WARN_ON(connector->state != old_conn_state);

		old_conn_state->state = state;
		new_conn_state->state = NULL;

		state->connectors[i].state = old_conn_state;
		connector->state = new_conn_state;
	}

	for_each_oldnew_crtc_in_state(state, crtc, old_crtc_state, new_crtc_state, i) {
		WARN_ON(crtc->state != old_crtc_state);

		old_crtc_state->state = state;
		new_crtc_state->state = NULL;

		state->crtcs[i].state = old_crtc_state;
		crtc->state = new_crtc_state;

		if (new_crtc_state->commit) {
			spin_lock(&crtc->commit_lock);
			list_add(&new_crtc_state->commit->commit_entry,
				 &crtc->commit_list);
			spin_unlock(&crtc->commit_lock);

			new_crtc_state->commit->event = NULL;
		}
	}

	for_each_oldnew_plane_in_state(state, plane, old_plane_state, new_plane_state, i) {
		WARN_ON(plane->state != old_plane_state);

		old_plane_state->state = state;
		new_plane_state->state = NULL;

		state->planes[i].state = old_plane_state;
		plane->state = new_plane_state;
	}

	for_each_oldnew_private_obj_in_state(state, obj, old_obj_state, new_obj_state, i) {
		WARN_ON(obj->state != old_obj_state);

		old_obj_state->state = state;
		new_obj_state->state = NULL;

		state->private_objs[i].state = old_obj_state;
		obj->state = new_obj_state;
	}

	return 0;
}
EXPORT_SYMBOL(drm_atomic_helper_swap_state);

/**
 * drm_atomic_helper_update_plane - Helper for primary plane update using atomic
 * @plane: plane object to update
 * @crtc: owning CRTC of owning plane
 * @fb: framebuffer to flip onto plane
 * @crtc_x: x offset of primary plane on crtc
 * @crtc_y: y offset of primary plane on crtc
 * @crtc_w: width of primary plane rectangle on crtc
 * @crtc_h: height of primary plane rectangle on crtc
 * @src_x: x offset of @fb for panning
 * @src_y: y offset of @fb for panning
 * @src_w: width of source rectangle in @fb
 * @src_h: height of source rectangle in @fb
 * @ctx: lock acquire context
 *
 * Provides a default plane update handler using the atomic driver interface.
 *
 * RETURNS:
 * Zero on success, error code on failure
 */
int drm_atomic_helper_update_plane(struct drm_plane *plane,
				   struct drm_crtc *crtc,
				   struct drm_framebuffer *fb,
				   int crtc_x, int crtc_y,
				   unsigned int crtc_w, unsigned int crtc_h,
				   uint32_t src_x, uint32_t src_y,
				   uint32_t src_w, uint32_t src_h,
				   struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_atomic_state *state;
	struct drm_plane_state *plane_state;
	int ret = 0;

	state = drm_atomic_state_alloc(plane->dev);
	if (!state)
		return -ENOMEM;

	state->acquire_ctx = ctx;
	plane_state = drm_atomic_get_plane_state(state, plane);
	if (IS_ERR(plane_state)) {
		ret = PTR_ERR(plane_state);
		goto fail;
	}

	ret = drm_atomic_set_crtc_for_plane(plane_state, crtc);
	if (ret != 0)
		goto fail;
	drm_atomic_set_fb_for_plane(plane_state, fb);
	plane_state->crtc_x = crtc_x;
	plane_state->crtc_y = crtc_y;
	plane_state->crtc_w = crtc_w;
	plane_state->crtc_h = crtc_h;
	plane_state->src_x = src_x;
	plane_state->src_y = src_y;
	plane_state->src_w = src_w;
	plane_state->src_h = src_h;

	if (plane == crtc->cursor)
		state->legacy_cursor_update = true;

	ret = drm_atomic_commit(state);
fail:
	drm_atomic_state_put(state);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_update_plane);

/**
 * drm_atomic_helper_disable_plane - Helper for primary plane disable using * atomic
 * @plane: plane to disable
 * @ctx: lock acquire context
 *
 * Provides a default plane disable handler using the atomic driver interface.
 *
 * RETURNS:
 * Zero on success, error code on failure
 */
int drm_atomic_helper_disable_plane(struct drm_plane *plane,
				    struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_atomic_state *state;
	struct drm_plane_state *plane_state;
	int ret = 0;

	state = drm_atomic_state_alloc(plane->dev);
	if (!state)
		return -ENOMEM;

	state->acquire_ctx = ctx;
	plane_state = drm_atomic_get_plane_state(state, plane);
	if (IS_ERR(plane_state)) {
		ret = PTR_ERR(plane_state);
		goto fail;
	}

	if (plane_state->crtc && plane_state->crtc->cursor == plane)
		plane_state->state->legacy_cursor_update = true;

	ret = __drm_atomic_helper_disable_plane(plane, plane_state);
	if (ret != 0)
		goto fail;

	ret = drm_atomic_commit(state);
fail:
	drm_atomic_state_put(state);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_disable_plane);

/**
 * drm_atomic_helper_set_config - set a new config from userspace
 * @set: mode set configuration
 * @ctx: lock acquisition context
 *
 * Provides a default crtc set_config handler using the atomic driver interface.
 *
 * NOTE: For backwards compatibility with old userspace this automatically
 * resets the "link-status" property to GOOD, to force any link
 * re-training. The SETCRTC ioctl does not define whether an update does
 * need a full modeset or just a plane update, hence we're allowed to do
 * that. See also drm_connector_set_link_status_property().
 *
 * Returns:
 * Returns 0 on success, negative errno numbers on failure.
 */
int drm_atomic_helper_set_config(struct drm_mode_set *set,
				 struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_atomic_state *state;
	struct drm_crtc *crtc = set->crtc;
	int ret = 0;

	state = drm_atomic_state_alloc(crtc->dev);
	if (!state)
		return -ENOMEM;

	state->acquire_ctx = ctx;
	ret = __drm_atomic_helper_set_config(set, state);
	if (ret != 0)
		goto fail;

	ret = handle_conflicting_encoders(state, true);
	if (ret)
		return ret;

	ret = drm_atomic_commit(state);

fail:
	drm_atomic_state_put(state);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_set_config);

/**
 * drm_atomic_helper_disable_all - disable all currently active outputs
 * @dev: DRM device
 * @ctx: lock acquisition context
 *
 * Loops through all connectors, finding those that aren't turned off and then
 * turns them off by setting their DPMS mode to OFF and deactivating the CRTC
 * that they are connected to.
 *
 * This is used for example in suspend/resume to disable all currently active
 * functions when suspending. If you just want to shut down everything at e.g.
 * driver unload, look at drm_atomic_helper_shutdown().
 *
 * Note that if callers haven't already acquired all modeset locks this might
 * return -EDEADLK, which must be handled by calling drm_modeset_backoff().
 *
 * Returns:
 * 0 on success or a negative error code on failure.
 *
 * See also:
 * drm_atomic_helper_suspend(), drm_atomic_helper_resume() and
 * drm_atomic_helper_shutdown().
 */
int drm_atomic_helper_disable_all(struct drm_device *dev,
				  struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_atomic_state *state;
	struct drm_connector_state *conn_state;
	struct drm_connector *conn;
	struct drm_plane_state *plane_state;
	struct drm_plane *plane;
	struct drm_crtc_state *crtc_state;
	struct drm_crtc *crtc;
	int ret, i;

	state = drm_atomic_state_alloc(dev);
	if (!state)
		return -ENOMEM;

	state->acquire_ctx = ctx;

	drm_for_each_crtc(crtc, dev) {
		crtc_state = drm_atomic_get_crtc_state(state, crtc);
		if (IS_ERR(crtc_state)) {
			ret = PTR_ERR(crtc_state);
			goto free;
		}

		crtc_state->active = false;

		ret = drm_atomic_set_mode_prop_for_crtc(crtc_state, NULL);
		if (ret < 0)
			goto free;

		ret = drm_atomic_add_affected_planes(state, crtc);
		if (ret < 0)
			goto free;

		ret = drm_atomic_add_affected_connectors(state, crtc);
		if (ret < 0)
			goto free;
	}

	for_each_new_connector_in_state(state, conn, conn_state, i) {
		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
		if (ret < 0)
			goto free;
	}

	for_each_new_plane_in_state(state, plane, plane_state, i) {
		ret = drm_atomic_set_crtc_for_plane(plane_state, NULL);
		if (ret < 0)
			goto free;

		drm_atomic_set_fb_for_plane(plane_state, NULL);
	}

	ret = drm_atomic_commit(state);
free:
	drm_atomic_state_put(state);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_disable_all);

/**
 * drm_atomic_helper_shutdown - shutdown all CRTC
 * @dev: DRM device
 *
 * This shuts down all CRTC, which is useful for driver unloading. Shutdown on
 * suspend should instead be handled with drm_atomic_helper_suspend(), since
 * that also takes a snapshot of the modeset state to be restored on resume.
 *
 * This is just a convenience wrapper around drm_atomic_helper_disable_all(),
 * and it is the atomic version of drm_crtc_force_disable_all().
 */
void drm_atomic_helper_shutdown(struct drm_device *dev)
{
	struct drm_modeset_acquire_ctx ctx;
	int ret;

	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, ret);

	ret = drm_atomic_helper_disable_all(dev, &ctx);
	if (ret)
		DRM_ERROR("Disabling all crtc's during unload failed with %i\n", ret);

	DRM_MODESET_LOCK_ALL_END(ctx, ret);
}
EXPORT_SYMBOL(drm_atomic_helper_shutdown);

/**
 * drm_atomic_helper_duplicate_state - duplicate an atomic state object
 * @dev: DRM device
 * @ctx: lock acquisition context
 *
 * Makes a copy of the current atomic state by looping over all objects and
 * duplicating their respective states. This is used for example by suspend/
 * resume support code to save the state prior to suspend such that it can
 * be restored upon resume.
 *
 * Note that this treats atomic state as persistent between save and restore.
 * Drivers must make sure that this is possible and won't result in confusion
 * or erroneous behaviour.
 *
 * Note that if callers haven't already acquired all modeset locks this might
 * return -EDEADLK, which must be handled by calling drm_modeset_backoff().
 *
 * Returns:
 * A pointer to the copy of the atomic state object on success or an
 * ERR_PTR()-encoded error code on failure.
 *
 * See also:
 * drm_atomic_helper_suspend(), drm_atomic_helper_resume()
 */
struct drm_atomic_state *
drm_atomic_helper_duplicate_state(struct drm_device *dev,
				  struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_atomic_state *state;
	struct drm_connector *conn;
	struct drm_connector_list_iter conn_iter;
	struct drm_plane *plane;
	struct drm_crtc *crtc;
	int err = 0;

	state = drm_atomic_state_alloc(dev);
	if (!state)
		return ERR_PTR(-ENOMEM);

	state->acquire_ctx = ctx;
	state->duplicated = true;

	drm_for_each_crtc(crtc, dev) {
		struct drm_crtc_state *crtc_state;

		crtc_state = drm_atomic_get_crtc_state(state, crtc);
		if (IS_ERR(crtc_state)) {
			err = PTR_ERR(crtc_state);
			goto free;
		}
	}

	drm_for_each_plane(plane, dev) {
		struct drm_plane_state *plane_state;

		plane_state = drm_atomic_get_plane_state(state, plane);
		if (IS_ERR(plane_state)) {
			err = PTR_ERR(plane_state);
			goto free;
		}
	}

	drm_connector_list_iter_begin(dev, &conn_iter);
	drm_for_each_connector_iter(conn, &conn_iter) {
		struct drm_connector_state *conn_state;

		conn_state = drm_atomic_get_connector_state(state, conn);
		if (IS_ERR(conn_state)) {
			err = PTR_ERR(conn_state);
			drm_connector_list_iter_end(&conn_iter);
			goto free;
		}
	}
	drm_connector_list_iter_end(&conn_iter);

	/* clear the acquire context so that it isn't accidentally reused */
	state->acquire_ctx = NULL;

free:
	if (err < 0) {
		drm_atomic_state_put(state);
		state = ERR_PTR(err);
	}

	return state;
}
EXPORT_SYMBOL(drm_atomic_helper_duplicate_state);

/**
 * drm_atomic_helper_suspend - subsystem-level suspend helper
 * @dev: DRM device
 *
 * Duplicates the current atomic state, disables all active outputs and then
 * returns a pointer to the original atomic state to the caller. Drivers can
 * pass this pointer to the drm_atomic_helper_resume() helper upon resume to
 * restore the output configuration that was active at the time the system
 * entered suspend.
 *
 * Note that it is potentially unsafe to use this. The atomic state object
 * returned by this function is assumed to be persistent. Drivers must ensure
 * that this holds true. Before calling this function, drivers must make sure
 * to suspend fbdev emulation so that nothing can be using the device.
 *
 * Returns:
 * A pointer to a copy of the state before suspend on success or an ERR_PTR()-
 * encoded error code on failure. Drivers should store the returned atomic
 * state object and pass it to the drm_atomic_helper_resume() helper upon
 * resume.
 *
 * See also:
 * drm_atomic_helper_duplicate_state(), drm_atomic_helper_disable_all(),
 * drm_atomic_helper_resume(), drm_atomic_helper_commit_duplicated_state()
 */
struct drm_atomic_state *drm_atomic_helper_suspend(struct drm_device *dev)
{
	struct drm_modeset_acquire_ctx ctx;
	struct drm_atomic_state *state;
	int err;

	/* This can never be returned, but it makes the compiler happy */
	state = ERR_PTR(-EINVAL);

	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, err);

	state = drm_atomic_helper_duplicate_state(dev, &ctx);
	if (IS_ERR(state))
		goto unlock;

	err = drm_atomic_helper_disable_all(dev, &ctx);
	if (err < 0) {
		drm_atomic_state_put(state);
		state = ERR_PTR(err);
		goto unlock;
	}

unlock:
	DRM_MODESET_LOCK_ALL_END(ctx, err);
	if (err)
		return ERR_PTR(err);

	return state;
}
EXPORT_SYMBOL(drm_atomic_helper_suspend);

/**
 * drm_atomic_helper_commit_duplicated_state - commit duplicated state
 * @state: duplicated atomic state to commit
 * @ctx: pointer to acquire_ctx to use for commit.
 *
 * The state returned by drm_atomic_helper_duplicate_state() and
 * drm_atomic_helper_suspend() is partially invalid, and needs to
 * be fixed up before commit.
 *
 * Returns:
 * 0 on success or a negative error code on failure.
 *
 * See also:
 * drm_atomic_helper_suspend()
 */
int drm_atomic_helper_commit_duplicated_state(struct drm_atomic_state *state,
					      struct drm_modeset_acquire_ctx *ctx)
{
	int i, ret;
	struct drm_plane *plane;
	struct drm_plane_state *new_plane_state;
	struct drm_connector *connector;
	struct drm_connector_state *new_conn_state;
	struct drm_crtc *crtc;
	struct drm_crtc_state *new_crtc_state;

	state->acquire_ctx = ctx;

	for_each_new_plane_in_state(state, plane, new_plane_state, i)
		state->planes[i].old_state = plane->state;

	for_each_new_crtc_in_state(state, crtc, new_crtc_state, i)
		state->crtcs[i].old_state = crtc->state;

	for_each_new_connector_in_state(state, connector, new_conn_state, i)
		state->connectors[i].old_state = connector->state;

	ret = drm_atomic_commit(state);

	state->acquire_ctx = NULL;

	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_commit_duplicated_state);

/**
 * drm_atomic_helper_resume - subsystem-level resume helper
 * @dev: DRM device
 * @state: atomic state to resume to
 *
 * Calls drm_mode_config_reset() to synchronize hardware and software states,
 * grabs all modeset locks and commits the atomic state object. This can be
 * used in conjunction with the drm_atomic_helper_suspend() helper to
 * implement suspend/resume for drivers that support atomic mode-setting.
 *
 * Returns:
 * 0 on success or a negative error code on failure.
 *
 * See also:
 * drm_atomic_helper_suspend()
 */
int drm_atomic_helper_resume(struct drm_device *dev,
			     struct drm_atomic_state *state)
{
	struct drm_modeset_acquire_ctx ctx;
	int err;

	drm_mode_config_reset(dev);

	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, err);

	err = drm_atomic_helper_commit_duplicated_state(state, &ctx);

	DRM_MODESET_LOCK_ALL_END(ctx, err);
	drm_atomic_state_put(state);

	return err;
}
EXPORT_SYMBOL(drm_atomic_helper_resume);

static int page_flip_common(struct drm_atomic_state *state,
			    struct drm_crtc *crtc,
			    struct drm_framebuffer *fb,
			    struct drm_pending_vblank_event *event,
			    uint32_t flags)
{
	struct drm_plane *plane = crtc->primary;
	struct drm_plane_state *plane_state;
	struct drm_crtc_state *crtc_state;
	int ret = 0;

	crtc_state = drm_atomic_get_crtc_state(state, crtc);
	if (IS_ERR(crtc_state))
		return PTR_ERR(crtc_state);

	crtc_state->event = event;
	crtc_state->async_flip = flags & DRM_MODE_PAGE_FLIP_ASYNC;

	plane_state = drm_atomic_get_plane_state(state, plane);
	if (IS_ERR(plane_state))
		return PTR_ERR(plane_state);

	ret = drm_atomic_set_crtc_for_plane(plane_state, crtc);
	if (ret != 0)
		return ret;
	drm_atomic_set_fb_for_plane(plane_state, fb);

	/* Make sure we don't accidentally do a full modeset. */
	state->allow_modeset = false;
	if (!crtc_state->active) {
		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] disabled, rejecting legacy flip\n",
				 crtc->base.id, crtc->name);
		return -EINVAL;
	}

	return ret;
}

/**
 * drm_atomic_helper_page_flip - execute a legacy page flip
 * @crtc: DRM crtc
 * @fb: DRM framebuffer
 * @event: optional DRM event to signal upon completion
 * @flags: flip flags for non-vblank sync'ed updates
 * @ctx: lock acquisition context
 *
 * Provides a default &drm_crtc_funcs.page_flip implementation
 * using the atomic driver interface.
 *
 * Returns:
 * Returns 0 on success, negative errno numbers on failure.
 *
 * See also:
 * drm_atomic_helper_page_flip_target()
 */
int drm_atomic_helper_page_flip(struct drm_crtc *crtc,
				struct drm_framebuffer *fb,
				struct drm_pending_vblank_event *event,
				uint32_t flags,
				struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_plane *plane = crtc->primary;
	struct drm_atomic_state *state;
	int ret = 0;

	state = drm_atomic_state_alloc(plane->dev);
	if (!state)
		return -ENOMEM;

	state->acquire_ctx = ctx;

	ret = page_flip_common(state, crtc, fb, event, flags);
	if (ret != 0)
		goto fail;

	ret = drm_atomic_nonblocking_commit(state);
fail:
	drm_atomic_state_put(state);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_page_flip);

/**
 * drm_atomic_helper_page_flip_target - do page flip on target vblank period.
 * @crtc: DRM crtc
 * @fb: DRM framebuffer
 * @event: optional DRM event to signal upon completion
 * @flags: flip flags for non-vblank sync'ed updates
 * @target: specifying the target vblank period when the flip to take effect
 * @ctx: lock acquisition context
 *
 * Provides a default &drm_crtc_funcs.page_flip_target implementation.
 * Similar to drm_atomic_helper_page_flip() with extra parameter to specify
 * target vblank period to flip.
 *
 * Returns:
 * Returns 0 on success, negative errno numbers on failure.
 */
int drm_atomic_helper_page_flip_target(struct drm_crtc *crtc,
				       struct drm_framebuffer *fb,
				       struct drm_pending_vblank_event *event,
				       uint32_t flags,
				       uint32_t target,
				       struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_plane *plane = crtc->primary;
	struct drm_atomic_state *state;
	struct drm_crtc_state *crtc_state;
	int ret = 0;

	state = drm_atomic_state_alloc(plane->dev);
	if (!state)
		return -ENOMEM;

	state->acquire_ctx = ctx;

	ret = page_flip_common(state, crtc, fb, event, flags);
	if (ret != 0)
		goto fail;

	crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
	if (WARN_ON(!crtc_state)) {
		ret = -EINVAL;
		goto fail;
	}
	crtc_state->target_vblank = target;

	ret = drm_atomic_nonblocking_commit(state);
fail:
	drm_atomic_state_put(state);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_page_flip_target);

/**
 * drm_atomic_helper_legacy_gamma_set - set the legacy gamma correction table
 * @crtc: CRTC object
 * @red: red correction table
 * @green: green correction table
 * @blue: green correction table
 * @size: size of the tables
 * @ctx: lock acquire context
 *
 * Implements support for legacy gamma correction table for drivers
 * that support color management through the DEGAMMA_LUT/GAMMA_LUT
 * properties. See drm_crtc_enable_color_mgmt() and the containing chapter for
 * how the atomic color management and gamma tables work.
 */
int drm_atomic_helper_legacy_gamma_set(struct drm_crtc *crtc,
				       u16 *red, u16 *green, u16 *blue,
				       uint32_t size,
				       struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_device *dev = crtc->dev;
	struct drm_atomic_state *state;
	struct drm_crtc_state *crtc_state;
	struct drm_property_blob *blob = NULL;
	struct drm_color_lut *blob_data;
	int i, ret = 0;
	bool replaced;

	state = drm_atomic_state_alloc(crtc->dev);
	if (!state)
		return -ENOMEM;

	blob = drm_property_create_blob(dev,
					sizeof(struct drm_color_lut) * size,
					NULL);
	if (IS_ERR(blob)) {
		ret = PTR_ERR(blob);
		blob = NULL;
		goto fail;
	}

	/* Prepare GAMMA_LUT with the legacy values. */
	blob_data = blob->data;
	for (i = 0; i < size; i++) {
		blob_data[i].red = red[i];
		blob_data[i].green = green[i];
		blob_data[i].blue = blue[i];
	}

	state->acquire_ctx = ctx;
	crtc_state = drm_atomic_get_crtc_state(state, crtc);
	if (IS_ERR(crtc_state)) {
		ret = PTR_ERR(crtc_state);
		goto fail;
	}

	/* Reset DEGAMMA_LUT and CTM properties. */
	replaced  = drm_property_replace_blob(&crtc_state->degamma_lut, NULL);
	replaced |= drm_property_replace_blob(&crtc_state->ctm, NULL);
	replaced |= drm_property_replace_blob(&crtc_state->gamma_lut, blob);
	crtc_state->color_mgmt_changed |= replaced;

	ret = drm_atomic_commit(state);

fail:
	drm_atomic_state_put(state);
	drm_property_blob_put(blob);
	return ret;
}
EXPORT_SYMBOL(drm_atomic_helper_legacy_gamma_set);