summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpiolib.c
blob: 78a16e42f222ebd81dc38f80da606f10daaef57e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
// SPDX-License-Identifier: GPL-2.0
#include <linux/bitmap.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/gpio.h>
#include <linux/idr.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/machine.h>
#include <linux/pinctrl/consumer.h>
#include <linux/cdev.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/compat.h>
#include <linux/anon_inodes.h>
#include <linux/file.h>
#include <linux/kfifo.h>
#include <linux/poll.h>
#include <linux/timekeeping.h>
#include <uapi/linux/gpio.h>

#include "gpiolib.h"
#include "gpiolib-of.h"
#include "gpiolib-acpi.h"

#define CREATE_TRACE_POINTS
#include <trace/events/gpio.h>

/* Implementation infrastructure for GPIO interfaces.
 *
 * The GPIO programming interface allows for inlining speed-critical
 * get/set operations for common cases, so that access to SOC-integrated
 * GPIOs can sometimes cost only an instruction or two per bit.
 */


/* When debugging, extend minimal trust to callers and platform code.
 * Also emit diagnostic messages that may help initial bringup, when
 * board setup or driver bugs are most common.
 *
 * Otherwise, minimize overhead in what may be bitbanging codepaths.
 */
#ifdef	DEBUG
#define	extra_checks	1
#else
#define	extra_checks	0
#endif

/* Device and char device-related information */
static DEFINE_IDA(gpio_ida);
static dev_t gpio_devt;
#define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */
static struct bus_type gpio_bus_type = {
	.name = "gpio",
};

/*
 * Number of GPIOs to use for the fast path in set array
 */
#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT

/* gpio_lock prevents conflicts during gpio_desc[] table updates.
 * While any GPIO is requested, its gpio_chip is not removable;
 * each GPIO's "requested" flag serves as a lock and refcount.
 */
DEFINE_SPINLOCK(gpio_lock);

static DEFINE_MUTEX(gpio_lookup_lock);
static LIST_HEAD(gpio_lookup_list);
LIST_HEAD(gpio_devices);

static DEFINE_MUTEX(gpio_machine_hogs_mutex);
static LIST_HEAD(gpio_machine_hogs);

static void gpiochip_free_hogs(struct gpio_chip *chip);
static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
				struct lock_class_key *lock_key,
				struct lock_class_key *request_key);
static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
static int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip);
static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip);
static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip);

static bool gpiolib_initialized;

static inline void desc_set_label(struct gpio_desc *d, const char *label)
{
	d->label = label;
}

/**
 * gpio_to_desc - Convert a GPIO number to its descriptor
 * @gpio: global GPIO number
 *
 * Returns:
 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO
 * with the given number exists in the system.
 */
struct gpio_desc *gpio_to_desc(unsigned gpio)
{
	struct gpio_device *gdev;
	unsigned long flags;

	spin_lock_irqsave(&gpio_lock, flags);

	list_for_each_entry(gdev, &gpio_devices, list) {
		if (gdev->base <= gpio &&
		    gdev->base + gdev->ngpio > gpio) {
			spin_unlock_irqrestore(&gpio_lock, flags);
			return &gdev->descs[gpio - gdev->base];
		}
	}

	spin_unlock_irqrestore(&gpio_lock, flags);

	if (!gpio_is_valid(gpio))
		WARN(1, "invalid GPIO %d\n", gpio);

	return NULL;
}
EXPORT_SYMBOL_GPL(gpio_to_desc);

/**
 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given
 *                     hardware number for this chip
 * @chip: GPIO chip
 * @hwnum: hardware number of the GPIO for this chip
 *
 * Returns:
 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists
 * in the given chip for the specified hardware number.
 */
struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
				    u16 hwnum)
{
	struct gpio_device *gdev = chip->gpiodev;

	if (hwnum >= gdev->ngpio)
		return ERR_PTR(-EINVAL);

	return &gdev->descs[hwnum];
}

/**
 * desc_to_gpio - convert a GPIO descriptor to the integer namespace
 * @desc: GPIO descriptor
 *
 * This should disappear in the future but is needed since we still
 * use GPIO numbers for error messages and sysfs nodes.
 *
 * Returns:
 * The global GPIO number for the GPIO specified by its descriptor.
 */
int desc_to_gpio(const struct gpio_desc *desc)
{
	return desc->gdev->base + (desc - &desc->gdev->descs[0]);
}
EXPORT_SYMBOL_GPL(desc_to_gpio);


/**
 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs
 * @desc:	descriptor to return the chip of
 */
struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
{
	if (!desc || !desc->gdev)
		return NULL;
	return desc->gdev->chip;
}
EXPORT_SYMBOL_GPL(gpiod_to_chip);

/* dynamic allocation of GPIOs, e.g. on a hotplugged device */
static int gpiochip_find_base(int ngpio)
{
	struct gpio_device *gdev;
	int base = ARCH_NR_GPIOS - ngpio;

	list_for_each_entry_reverse(gdev, &gpio_devices, list) {
		/* found a free space? */
		if (gdev->base + gdev->ngpio <= base)
			break;
		else
			/* nope, check the space right before the chip */
			base = gdev->base - ngpio;
	}

	if (gpio_is_valid(base)) {
		pr_debug("%s: found new base at %d\n", __func__, base);
		return base;
	} else {
		pr_err("%s: cannot find free range\n", __func__);
		return -ENOSPC;
	}
}

/**
 * gpiod_get_direction - return the current direction of a GPIO
 * @desc:	GPIO to get the direction of
 *
 * Returns 0 for output, 1 for input, or an error code in case of error.
 *
 * This function may sleep if gpiod_cansleep() is true.
 */
int gpiod_get_direction(struct gpio_desc *desc)
{
	struct gpio_chip *chip;
	unsigned offset;
	int ret;

	chip = gpiod_to_chip(desc);
	offset = gpio_chip_hwgpio(desc);

	/*
	 * Open drain emulation using input mode may incorrectly report
	 * input here, fix that up.
	 */
	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
	    test_bit(FLAG_IS_OUT, &desc->flags))
		return 0;

	if (!chip->get_direction)
		return -ENOTSUPP;

	ret = chip->get_direction(chip, offset);
	if (ret > 0) {
		/* GPIOF_DIR_IN, or other positive */
		ret = 1;
		clear_bit(FLAG_IS_OUT, &desc->flags);
	}
	if (ret == 0) {
		/* GPIOF_DIR_OUT */
		set_bit(FLAG_IS_OUT, &desc->flags);
	}
	return ret;
}
EXPORT_SYMBOL_GPL(gpiod_get_direction);

/*
 * Add a new chip to the global chips list, keeping the list of chips sorted
 * by range(means [base, base + ngpio - 1]) order.
 *
 * Return -EBUSY if the new chip overlaps with some other chip's integer
 * space.
 */
static int gpiodev_add_to_list(struct gpio_device *gdev)
{
	struct gpio_device *prev, *next;

	if (list_empty(&gpio_devices)) {
		/* initial entry in list */
		list_add_tail(&gdev->list, &gpio_devices);
		return 0;
	}

	next = list_entry(gpio_devices.next, struct gpio_device, list);
	if (gdev->base + gdev->ngpio <= next->base) {
		/* add before first entry */
		list_add(&gdev->list, &gpio_devices);
		return 0;
	}

	prev = list_entry(gpio_devices.prev, struct gpio_device, list);
	if (prev->base + prev->ngpio <= gdev->base) {
		/* add behind last entry */
		list_add_tail(&gdev->list, &gpio_devices);
		return 0;
	}

	list_for_each_entry_safe(prev, next, &gpio_devices, list) {
		/* at the end of the list */
		if (&next->list == &gpio_devices)
			break;

		/* add between prev and next */
		if (prev->base + prev->ngpio <= gdev->base
				&& gdev->base + gdev->ngpio <= next->base) {
			list_add(&gdev->list, &prev->list);
			return 0;
		}
	}

	dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n");
	return -EBUSY;
}

/*
 * Convert a GPIO name to its descriptor
 */
static struct gpio_desc *gpio_name_to_desc(const char * const name)
{
	struct gpio_device *gdev;
	unsigned long flags;

	spin_lock_irqsave(&gpio_lock, flags);

	list_for_each_entry(gdev, &gpio_devices, list) {
		int i;

		for (i = 0; i != gdev->ngpio; ++i) {
			struct gpio_desc *desc = &gdev->descs[i];

			if (!desc->name || !name)
				continue;

			if (!strcmp(desc->name, name)) {
				spin_unlock_irqrestore(&gpio_lock, flags);
				return desc;
			}
		}
	}

	spin_unlock_irqrestore(&gpio_lock, flags);

	return NULL;
}

/*
 * Takes the names from gc->names and checks if they are all unique. If they
 * are, they are assigned to their gpio descriptors.
 *
 * Warning if one of the names is already used for a different GPIO.
 */
static int gpiochip_set_desc_names(struct gpio_chip *gc)
{
	struct gpio_device *gdev = gc->gpiodev;
	int i;

	if (!gc->names)
		return 0;

	/* First check all names if they are unique */
	for (i = 0; i != gc->ngpio; ++i) {
		struct gpio_desc *gpio;

		gpio = gpio_name_to_desc(gc->names[i]);
		if (gpio)
			dev_warn(&gdev->dev,
				 "Detected name collision for GPIO name '%s'\n",
				 gc->names[i]);
	}

	/* Then add all names to the GPIO descriptors */
	for (i = 0; i != gc->ngpio; ++i)
		gdev->descs[i].name = gc->names[i];

	return 0;
}

static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip)
{
	unsigned long *p;

	p = bitmap_alloc(chip->ngpio, GFP_KERNEL);
	if (!p)
		return NULL;

	/* Assume by default all GPIOs are valid */
	bitmap_fill(p, chip->ngpio);

	return p;
}

static int gpiochip_alloc_valid_mask(struct gpio_chip *gc)
{
	if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask))
		return 0;

	gc->valid_mask = gpiochip_allocate_mask(gc);
	if (!gc->valid_mask)
		return -ENOMEM;

	return 0;
}

static int gpiochip_init_valid_mask(struct gpio_chip *gc)
{
	if (gc->init_valid_mask)
		return gc->init_valid_mask(gc,
					   gc->valid_mask,
					   gc->ngpio);

	return 0;
}

static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip)
{
	bitmap_free(gpiochip->valid_mask);
	gpiochip->valid_mask = NULL;
}

static int gpiochip_add_pin_ranges(struct gpio_chip *gc)
{
	if (gc->add_pin_ranges)
		return gc->add_pin_ranges(gc);

	return 0;
}

bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip,
				unsigned int offset)
{
	/* No mask means all valid */
	if (likely(!gpiochip->valid_mask))
		return true;
	return test_bit(offset, gpiochip->valid_mask);
}
EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);

/*
 * GPIO line handle management
 */

/**
 * struct linehandle_state - contains the state of a userspace handle
 * @gdev: the GPIO device the handle pertains to
 * @label: consumer label used to tag descriptors
 * @descs: the GPIO descriptors held by this handle
 * @numdescs: the number of descriptors held in the descs array
 */
struct linehandle_state {
	struct gpio_device *gdev;
	const char *label;
	struct gpio_desc *descs[GPIOHANDLES_MAX];
	u32 numdescs;
};

#define GPIOHANDLE_REQUEST_VALID_FLAGS \
	(GPIOHANDLE_REQUEST_INPUT | \
	GPIOHANDLE_REQUEST_OUTPUT | \
	GPIOHANDLE_REQUEST_ACTIVE_LOW | \
	GPIOHANDLE_REQUEST_BIAS_PULL_UP | \
	GPIOHANDLE_REQUEST_BIAS_PULL_DOWN | \
	GPIOHANDLE_REQUEST_BIAS_DISABLE | \
	GPIOHANDLE_REQUEST_OPEN_DRAIN | \
	GPIOHANDLE_REQUEST_OPEN_SOURCE)

static int linehandle_validate_flags(u32 flags)
{
	/* Return an error if an unknown flag is set */
	if (flags & ~GPIOHANDLE_REQUEST_VALID_FLAGS)
		return -EINVAL;

	/*
	 * Do not allow both INPUT & OUTPUT flags to be set as they are
	 * contradictory.
	 */
	if ((flags & GPIOHANDLE_REQUEST_INPUT) &&
	    (flags & GPIOHANDLE_REQUEST_OUTPUT))
		return -EINVAL;

	/*
	 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If
	 * the hardware actually supports enabling both at the same time the
	 * electrical result would be disastrous.
	 */
	if ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) &&
	    (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
		return -EINVAL;

	/* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */
	if (!(flags & GPIOHANDLE_REQUEST_OUTPUT) &&
	    ((flags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
	     (flags & GPIOHANDLE_REQUEST_OPEN_SOURCE)))
		return -EINVAL;

	/* Bias flags only allowed for input or output mode. */
	if (!((flags & GPIOHANDLE_REQUEST_INPUT) ||
	      (flags & GPIOHANDLE_REQUEST_OUTPUT)) &&
	    ((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) ||
	     (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP) ||
	     (flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)))
		return -EINVAL;

	/* Only one bias flag can be set. */
	if (((flags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
	     (flags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
			GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
	    ((flags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
	     (flags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
		return -EINVAL;

	return 0;
}

static void linehandle_configure_flag(unsigned long *flagsp,
				      u32 bit, bool active)
{
	if (active)
		set_bit(bit, flagsp);
	else
		clear_bit(bit, flagsp);
}

static long linehandle_set_config(struct linehandle_state *lh,
				  void __user *ip)
{
	struct gpiohandle_config gcnf;
	struct gpio_desc *desc;
	int i, ret;
	u32 lflags;
	unsigned long *flagsp;

	if (copy_from_user(&gcnf, ip, sizeof(gcnf)))
		return -EFAULT;

	lflags = gcnf.flags;
	ret = linehandle_validate_flags(lflags);
	if (ret)
		return ret;

	for (i = 0; i < lh->numdescs; i++) {
		desc = lh->descs[i];
		flagsp = &desc->flags;

		linehandle_configure_flag(flagsp, FLAG_ACTIVE_LOW,
			lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW);

		linehandle_configure_flag(flagsp, FLAG_OPEN_DRAIN,
			lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN);

		linehandle_configure_flag(flagsp, FLAG_OPEN_SOURCE,
			lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE);

		linehandle_configure_flag(flagsp, FLAG_PULL_UP,
			lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP);

		linehandle_configure_flag(flagsp, FLAG_PULL_DOWN,
			lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN);

		linehandle_configure_flag(flagsp, FLAG_BIAS_DISABLE,
			lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE);

		/*
		 * Lines have to be requested explicitly for input
		 * or output, else the line will be treated "as is".
		 */
		if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
			int val = !!gcnf.default_values[i];

			ret = gpiod_direction_output(desc, val);
			if (ret)
				return ret;
		} else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
			ret = gpiod_direction_input(desc);
			if (ret)
				return ret;
		}
	}
	return 0;
}

static long linehandle_ioctl(struct file *filep, unsigned int cmd,
			     unsigned long arg)
{
	struct linehandle_state *lh = filep->private_data;
	void __user *ip = (void __user *)arg;
	struct gpiohandle_data ghd;
	DECLARE_BITMAP(vals, GPIOHANDLES_MAX);
	int i;

	if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
		/* NOTE: It's ok to read values of output lines. */
		int ret = gpiod_get_array_value_complex(false,
							true,
							lh->numdescs,
							lh->descs,
							NULL,
							vals);
		if (ret)
			return ret;

		memset(&ghd, 0, sizeof(ghd));
		for (i = 0; i < lh->numdescs; i++)
			ghd.values[i] = test_bit(i, vals);

		if (copy_to_user(ip, &ghd, sizeof(ghd)))
			return -EFAULT;

		return 0;
	} else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) {
		/*
		 * All line descriptors were created at once with the same
		 * flags so just check if the first one is really output.
		 */
		if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags))
			return -EPERM;

		if (copy_from_user(&ghd, ip, sizeof(ghd)))
			return -EFAULT;

		/* Clamp all values to [0,1] */
		for (i = 0; i < lh->numdescs; i++)
			__assign_bit(i, vals, ghd.values[i]);

		/* Reuse the array setting function */
		return gpiod_set_array_value_complex(false,
					      true,
					      lh->numdescs,
					      lh->descs,
					      NULL,
					      vals);
	} else if (cmd == GPIOHANDLE_SET_CONFIG_IOCTL) {
		return linehandle_set_config(lh, ip);
	}
	return -EINVAL;
}

#ifdef CONFIG_COMPAT
static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd,
			     unsigned long arg)
{
	return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
}
#endif

static int linehandle_release(struct inode *inode, struct file *filep)
{
	struct linehandle_state *lh = filep->private_data;
	struct gpio_device *gdev = lh->gdev;
	int i;

	for (i = 0; i < lh->numdescs; i++)
		gpiod_free(lh->descs[i]);
	kfree(lh->label);
	kfree(lh);
	put_device(&gdev->dev);
	return 0;
}

static const struct file_operations linehandle_fileops = {
	.release = linehandle_release,
	.owner = THIS_MODULE,
	.llseek = noop_llseek,
	.unlocked_ioctl = linehandle_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = linehandle_ioctl_compat,
#endif
};

static int linehandle_create(struct gpio_device *gdev, void __user *ip)
{
	struct gpiohandle_request handlereq;
	struct linehandle_state *lh;
	struct file *file;
	int fd, i, count = 0, ret;
	u32 lflags;

	if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
		return -EFAULT;
	if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
		return -EINVAL;

	lflags = handlereq.flags;

	ret = linehandle_validate_flags(lflags);
	if (ret)
		return ret;

	lh = kzalloc(sizeof(*lh), GFP_KERNEL);
	if (!lh)
		return -ENOMEM;
	lh->gdev = gdev;
	get_device(&gdev->dev);

	/* Make sure this is terminated */
	handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0';
	if (strlen(handlereq.consumer_label)) {
		lh->label = kstrdup(handlereq.consumer_label,
				    GFP_KERNEL);
		if (!lh->label) {
			ret = -ENOMEM;
			goto out_free_lh;
		}
	}

	/* Request each GPIO */
	for (i = 0; i < handlereq.lines; i++) {
		u32 offset = handlereq.lineoffsets[i];
		struct gpio_desc *desc;

		if (offset >= gdev->ngpio) {
			ret = -EINVAL;
			goto out_free_descs;
		}

		desc = &gdev->descs[offset];
		ret = gpiod_request(desc, lh->label);
		if (ret)
			goto out_free_descs;
		lh->descs[i] = desc;
		count = i + 1;

		if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
			set_bit(FLAG_ACTIVE_LOW, &desc->flags);
		if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
			set_bit(FLAG_OPEN_DRAIN, &desc->flags);
		if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
			set_bit(FLAG_OPEN_SOURCE, &desc->flags);
		if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
			set_bit(FLAG_BIAS_DISABLE, &desc->flags);
		if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
			set_bit(FLAG_PULL_DOWN, &desc->flags);
		if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
			set_bit(FLAG_PULL_UP, &desc->flags);

		ret = gpiod_set_transitory(desc, false);
		if (ret < 0)
			goto out_free_descs;

		/*
		 * Lines have to be requested explicitly for input
		 * or output, else the line will be treated "as is".
		 */
		if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
			int val = !!handlereq.default_values[i];

			ret = gpiod_direction_output(desc, val);
			if (ret)
				goto out_free_descs;
		} else if (lflags & GPIOHANDLE_REQUEST_INPUT) {
			ret = gpiod_direction_input(desc);
			if (ret)
				goto out_free_descs;
		}
		dev_dbg(&gdev->dev, "registered chardev handle for line %d\n",
			offset);
	}
	/* Let i point at the last handle */
	i--;
	lh->numdescs = handlereq.lines;

	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
	if (fd < 0) {
		ret = fd;
		goto out_free_descs;
	}

	file = anon_inode_getfile("gpio-linehandle",
				  &linehandle_fileops,
				  lh,
				  O_RDONLY | O_CLOEXEC);
	if (IS_ERR(file)) {
		ret = PTR_ERR(file);
		goto out_put_unused_fd;
	}

	handlereq.fd = fd;
	if (copy_to_user(ip, &handlereq, sizeof(handlereq))) {
		/*
		 * fput() will trigger the release() callback, so do not go onto
		 * the regular error cleanup path here.
		 */
		fput(file);
		put_unused_fd(fd);
		return -EFAULT;
	}

	fd_install(fd, file);

	dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n",
		lh->numdescs);

	return 0;

out_put_unused_fd:
	put_unused_fd(fd);
out_free_descs:
	for (i = 0; i < count; i++)
		gpiod_free(lh->descs[i]);
	kfree(lh->label);
out_free_lh:
	kfree(lh);
	put_device(&gdev->dev);
	return ret;
}

/*
 * GPIO line event management
 */

/**
 * struct lineevent_state - contains the state of a userspace event
 * @gdev: the GPIO device the event pertains to
 * @label: consumer label used to tag descriptors
 * @desc: the GPIO descriptor held by this event
 * @eflags: the event flags this line was requested with
 * @irq: the interrupt that trigger in response to events on this GPIO
 * @wait: wait queue that handles blocking reads of events
 * @events: KFIFO for the GPIO events
 * @read_lock: mutex lock to protect reads from colliding with adding
 * new events to the FIFO
 * @timestamp: cache for the timestamp storing it between hardirq
 * and IRQ thread, used to bring the timestamp close to the actual
 * event
 */
struct lineevent_state {
	struct gpio_device *gdev;
	const char *label;
	struct gpio_desc *desc;
	u32 eflags;
	int irq;
	wait_queue_head_t wait;
	DECLARE_KFIFO(events, struct gpioevent_data, 16);
	struct mutex read_lock;
	u64 timestamp;
};

#define GPIOEVENT_REQUEST_VALID_FLAGS \
	(GPIOEVENT_REQUEST_RISING_EDGE | \
	GPIOEVENT_REQUEST_FALLING_EDGE)

static __poll_t lineevent_poll(struct file *filep,
				   struct poll_table_struct *wait)
{
	struct lineevent_state *le = filep->private_data;
	__poll_t events = 0;

	poll_wait(filep, &le->wait, wait);

	if (!kfifo_is_empty(&le->events))
		events = EPOLLIN | EPOLLRDNORM;

	return events;
}


static ssize_t lineevent_read(struct file *filep,
			      char __user *buf,
			      size_t count,
			      loff_t *f_ps)
{
	struct lineevent_state *le = filep->private_data;
	unsigned int copied;
	int ret;

	if (count < sizeof(struct gpioevent_data))
		return -EINVAL;

	do {
		if (kfifo_is_empty(&le->events)) {
			if (filep->f_flags & O_NONBLOCK)
				return -EAGAIN;

			ret = wait_event_interruptible(le->wait,
					!kfifo_is_empty(&le->events));
			if (ret)
				return ret;
		}

		if (mutex_lock_interruptible(&le->read_lock))
			return -ERESTARTSYS;
		ret = kfifo_to_user(&le->events, buf, count, &copied);
		mutex_unlock(&le->read_lock);

		if (ret)
			return ret;

		/*
		 * If we couldn't read anything from the fifo (a different
		 * thread might have been faster) we either return -EAGAIN if
		 * the file descriptor is non-blocking, otherwise we go back to
		 * sleep and wait for more data to arrive.
		 */
		if (copied == 0 && (filep->f_flags & O_NONBLOCK))
			return -EAGAIN;

	} while (copied == 0);

	return copied;
}

static int lineevent_release(struct inode *inode, struct file *filep)
{
	struct lineevent_state *le = filep->private_data;
	struct gpio_device *gdev = le->gdev;

	free_irq(le->irq, le);
	gpiod_free(le->desc);
	kfree(le->label);
	kfree(le);
	put_device(&gdev->dev);
	return 0;
}

static long lineevent_ioctl(struct file *filep, unsigned int cmd,
			    unsigned long arg)
{
	struct lineevent_state *le = filep->private_data;
	void __user *ip = (void __user *)arg;
	struct gpiohandle_data ghd;

	/*
	 * We can get the value for an event line but not set it,
	 * because it is input by definition.
	 */
	if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) {
		int val;

		memset(&ghd, 0, sizeof(ghd));

		val = gpiod_get_value_cansleep(le->desc);
		if (val < 0)
			return val;
		ghd.values[0] = val;

		if (copy_to_user(ip, &ghd, sizeof(ghd)))
			return -EFAULT;

		return 0;
	}
	return -EINVAL;
}

#ifdef CONFIG_COMPAT
static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd,
				   unsigned long arg)
{
	return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg));
}
#endif

static const struct file_operations lineevent_fileops = {
	.release = lineevent_release,
	.read = lineevent_read,
	.poll = lineevent_poll,
	.owner = THIS_MODULE,
	.llseek = noop_llseek,
	.unlocked_ioctl = lineevent_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = lineevent_ioctl_compat,
#endif
};

static irqreturn_t lineevent_irq_thread(int irq, void *p)
{
	struct lineevent_state *le = p;
	struct gpioevent_data ge;
	int ret;

	/* Do not leak kernel stack to userspace */
	memset(&ge, 0, sizeof(ge));

	/*
	 * We may be running from a nested threaded interrupt in which case
	 * we didn't get the timestamp from lineevent_irq_handler().
	 */
	if (!le->timestamp)
		ge.timestamp = ktime_get_real_ns();
	else
		ge.timestamp = le->timestamp;

	if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE
	    && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
		int level = gpiod_get_value_cansleep(le->desc);
		if (level)
			/* Emit low-to-high event */
			ge.id = GPIOEVENT_EVENT_RISING_EDGE;
		else
			/* Emit high-to-low event */
			ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
	} else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) {
		/* Emit low-to-high event */
		ge.id = GPIOEVENT_EVENT_RISING_EDGE;
	} else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) {
		/* Emit high-to-low event */
		ge.id = GPIOEVENT_EVENT_FALLING_EDGE;
	} else {
		return IRQ_NONE;
	}

	ret = kfifo_put(&le->events, ge);
	if (ret)
		wake_up_poll(&le->wait, EPOLLIN);

	return IRQ_HANDLED;
}

static irqreturn_t lineevent_irq_handler(int irq, void *p)
{
	struct lineevent_state *le = p;

	/*
	 * Just store the timestamp in hardirq context so we get it as
	 * close in time as possible to the actual event.
	 */
	le->timestamp = ktime_get_real_ns();

	return IRQ_WAKE_THREAD;
}

static int lineevent_create(struct gpio_device *gdev, void __user *ip)
{
	struct gpioevent_request eventreq;
	struct lineevent_state *le;
	struct gpio_desc *desc;
	struct file *file;
	u32 offset;
	u32 lflags;
	u32 eflags;
	int fd;
	int ret;
	int irqflags = 0;

	if (copy_from_user(&eventreq, ip, sizeof(eventreq)))
		return -EFAULT;

	offset = eventreq.lineoffset;
	lflags = eventreq.handleflags;
	eflags = eventreq.eventflags;

	if (offset >= gdev->ngpio)
		return -EINVAL;

	/* Return an error if a unknown flag is set */
	if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) ||
	    (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS))
		return -EINVAL;

	/* This is just wrong: we don't look for events on output lines */
	if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
	    (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
	    (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))
		return -EINVAL;

	/* Only one bias flag can be set. */
	if (((lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE) &&
	     (lflags & (GPIOHANDLE_REQUEST_BIAS_PULL_DOWN |
			GPIOHANDLE_REQUEST_BIAS_PULL_UP))) ||
	    ((lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN) &&
	     (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)))
		return -EINVAL;

	le = kzalloc(sizeof(*le), GFP_KERNEL);
	if (!le)
		return -ENOMEM;
	le->gdev = gdev;
	get_device(&gdev->dev);

	/* Make sure this is terminated */
	eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0';
	if (strlen(eventreq.consumer_label)) {
		le->label = kstrdup(eventreq.consumer_label,
				    GFP_KERNEL);
		if (!le->label) {
			ret = -ENOMEM;
			goto out_free_le;
		}
	}

	desc = &gdev->descs[offset];
	ret = gpiod_request(desc, le->label);
	if (ret)
		goto out_free_label;
	le->desc = desc;
	le->eflags = eflags;

	if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
		set_bit(FLAG_ACTIVE_LOW, &desc->flags);
	if (lflags & GPIOHANDLE_REQUEST_BIAS_DISABLE)
		set_bit(FLAG_BIAS_DISABLE, &desc->flags);
	if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_DOWN)
		set_bit(FLAG_PULL_DOWN, &desc->flags);
	if (lflags & GPIOHANDLE_REQUEST_BIAS_PULL_UP)
		set_bit(FLAG_PULL_UP, &desc->flags);

	ret = gpiod_direction_input(desc);
	if (ret)
		goto out_free_desc;

	le->irq = gpiod_to_irq(desc);
	if (le->irq <= 0) {
		ret = -ENODEV;
		goto out_free_desc;
	}

	if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
		irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
			IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
	if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
		irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
			IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
	irqflags |= IRQF_ONESHOT;

	INIT_KFIFO(le->events);
	init_waitqueue_head(&le->wait);
	mutex_init(&le->read_lock);

	/* Request a thread to read the events */
	ret = request_threaded_irq(le->irq,
			lineevent_irq_handler,
			lineevent_irq_thread,
			irqflags,
			le->label,
			le);
	if (ret)
		goto out_free_desc;

	fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
	if (fd < 0) {
		ret = fd;
		goto out_free_irq;
	}

	file = anon_inode_getfile("gpio-event",
				  &lineevent_fileops,
				  le,
				  O_RDONLY | O_CLOEXEC);
	if (IS_ERR(file)) {
		ret = PTR_ERR(file);
		goto out_put_unused_fd;
	}

	eventreq.fd = fd;
	if (copy_to_user(ip, &eventreq, sizeof(eventreq))) {
		/*
		 * fput() will trigger the release() callback, so do not go onto
		 * the regular error cleanup path here.
		 */
		fput(file);
		put_unused_fd(fd);
		return -EFAULT;
	}

	fd_install(fd, file);

	return 0;

out_put_unused_fd:
	put_unused_fd(fd);
out_free_irq:
	free_irq(le->irq, le);
out_free_desc:
	gpiod_free(le->desc);
out_free_label:
	kfree(le->label);
out_free_le:
	kfree(le);
	put_device(&gdev->dev);
	return ret;
}

/*
 * gpio_ioctl() - ioctl handler for the GPIO chardev
 */
static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct gpio_device *gdev = filp->private_data;
	struct gpio_chip *chip = gdev->chip;
	void __user *ip = (void __user *)arg;

	/* We fail any subsequent ioctl():s when the chip is gone */
	if (!chip)
		return -ENODEV;

	/* Fill in the struct and pass to userspace */
	if (cmd == GPIO_GET_CHIPINFO_IOCTL) {
		struct gpiochip_info chipinfo;

		memset(&chipinfo, 0, sizeof(chipinfo));

		strncpy(chipinfo.name, dev_name(&gdev->dev),
			sizeof(chipinfo.name));
		chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
		strncpy(chipinfo.label, gdev->label,
			sizeof(chipinfo.label));
		chipinfo.label[sizeof(chipinfo.label)-1] = '\0';
		chipinfo.lines = gdev->ngpio;
		if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
			return -EFAULT;
		return 0;
	} else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
		struct gpioline_info lineinfo;
		struct gpio_desc *desc;

		if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
			return -EFAULT;
		if (lineinfo.line_offset >= gdev->ngpio)
			return -EINVAL;

		desc = &gdev->descs[lineinfo.line_offset];
		if (desc->name) {
			strncpy(lineinfo.name, desc->name,
				sizeof(lineinfo.name));
			lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
		} else {
			lineinfo.name[0] = '\0';
		}
		if (desc->label) {
			strncpy(lineinfo.consumer, desc->label,
				sizeof(lineinfo.consumer));
			lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
		} else {
			lineinfo.consumer[0] = '\0';
		}

		/*
		 * Userspace only need to know that the kernel is using
		 * this GPIO so it can't use it.
		 */
		lineinfo.flags = 0;
		if (test_bit(FLAG_REQUESTED, &desc->flags) ||
		    test_bit(FLAG_IS_HOGGED, &desc->flags) ||
		    test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
		    test_bit(FLAG_EXPORT, &desc->flags) ||
		    test_bit(FLAG_SYSFS, &desc->flags) ||
		    !pinctrl_gpio_can_use_line(chip->base + lineinfo.line_offset))
			lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
		if (test_bit(FLAG_IS_OUT, &desc->flags))
			lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
		if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
			lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
		if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
			lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
					   GPIOLINE_FLAG_IS_OUT);
		if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
			lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
					   GPIOLINE_FLAG_IS_OUT);
		if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
			lineinfo.flags |= GPIOLINE_FLAG_BIAS_DISABLE;
		if (test_bit(FLAG_PULL_DOWN, &desc->flags))
			lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN;
		if (test_bit(FLAG_PULL_UP, &desc->flags))
			lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_UP;

		if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
			return -EFAULT;
		return 0;
	} else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
		return linehandle_create(gdev, ip);
	} else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
		return lineevent_create(gdev, ip);
	}
	return -EINVAL;
}

#ifdef CONFIG_COMPAT
static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
			      unsigned long arg)
{
	return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
}
#endif

/**
 * gpio_chrdev_open() - open the chardev for ioctl operations
 * @inode: inode for this chardev
 * @filp: file struct for storing private data
 * Returns 0 on success
 */
static int gpio_chrdev_open(struct inode *inode, struct file *filp)
{
	struct gpio_device *gdev = container_of(inode->i_cdev,
					      struct gpio_device, chrdev);

	/* Fail on open if the backing gpiochip is gone */
	if (!gdev->chip)
		return -ENODEV;
	get_device(&gdev->dev);
	filp->private_data = gdev;

	return nonseekable_open(inode, filp);
}

/**
 * gpio_chrdev_release() - close chardev after ioctl operations
 * @inode: inode for this chardev
 * @filp: file struct for storing private data
 * Returns 0 on success
 */
static int gpio_chrdev_release(struct inode *inode, struct file *filp)
{
	struct gpio_device *gdev = container_of(inode->i_cdev,
					      struct gpio_device, chrdev);

	put_device(&gdev->dev);
	return 0;
}


static const struct file_operations gpio_fileops = {
	.release = gpio_chrdev_release,
	.open = gpio_chrdev_open,
	.owner = THIS_MODULE,
	.llseek = no_llseek,
	.unlocked_ioctl = gpio_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl = gpio_ioctl_compat,
#endif
};

static void gpiodevice_release(struct device *dev)
{
	struct gpio_device *gdev = dev_get_drvdata(dev);

	list_del(&gdev->list);
	ida_simple_remove(&gpio_ida, gdev->id);
	kfree_const(gdev->label);
	kfree(gdev->descs);
	kfree(gdev);
}

static int gpiochip_setup_dev(struct gpio_device *gdev)
{
	int ret;

	cdev_init(&gdev->chrdev, &gpio_fileops);
	gdev->chrdev.owner = THIS_MODULE;
	gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);

	ret = cdev_device_add(&gdev->chrdev, &gdev->dev);
	if (ret)
		return ret;

	chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
		 MAJOR(gpio_devt), gdev->id);

	ret = gpiochip_sysfs_register(gdev);
	if (ret)
		goto err_remove_device;

	/* From this point, the .release() function cleans up gpio_device */
	gdev->dev.release = gpiodevice_release;
	pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
		 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
		 dev_name(&gdev->dev), gdev->chip->label ? : "generic");

	return 0;

err_remove_device:
	cdev_device_del(&gdev->chrdev, &gdev->dev);
	return ret;
}

static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
{
	struct gpio_desc *desc;
	int rv;

	desc = gpiochip_get_desc(chip, hog->chip_hwnum);
	if (IS_ERR(desc)) {
		pr_err("%s: unable to get GPIO desc: %ld\n",
		       __func__, PTR_ERR(desc));
		return;
	}

	if (test_bit(FLAG_IS_HOGGED, &desc->flags))
		return;

	rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
	if (rv)
		pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
		       __func__, chip->label, hog->chip_hwnum, rv);
}

static void machine_gpiochip_add(struct gpio_chip *chip)
{
	struct gpiod_hog *hog;

	mutex_lock(&gpio_machine_hogs_mutex);

	list_for_each_entry(hog, &gpio_machine_hogs, list) {
		if (!strcmp(chip->label, hog->chip_label))
			gpiochip_machine_hog(chip, hog);
	}

	mutex_unlock(&gpio_machine_hogs_mutex);
}

static void gpiochip_setup_devs(void)
{
	struct gpio_device *gdev;
	int ret;

	list_for_each_entry(gdev, &gpio_devices, list) {
		ret = gpiochip_setup_dev(gdev);
		if (ret)
			pr_err("%s: Failed to initialize gpio device (%d)\n",
			       dev_name(&gdev->dev), ret);
	}
}

int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
			       struct lock_class_key *lock_key,
			       struct lock_class_key *request_key)
{
	unsigned long	flags;
	int		ret = 0;
	unsigned	i;
	int		base = chip->base;
	struct gpio_device *gdev;

	/*
	 * First: allocate and populate the internal stat container, and
	 * set up the struct device.
	 */
	gdev = kzalloc(sizeof(*gdev), GFP_KERNEL);
	if (!gdev)
		return -ENOMEM;
	gdev->dev.bus = &gpio_bus_type;
	gdev->chip = chip;
	chip->gpiodev = gdev;
	if (chip->parent) {
		gdev->dev.parent = chip->parent;
		gdev->dev.of_node = chip->parent->of_node;
	}

#ifdef CONFIG_OF_GPIO
	/* If the gpiochip has an assigned OF node this takes precedence */
	if (chip->of_node)
		gdev->dev.of_node = chip->of_node;
	else
		chip->of_node = gdev->dev.of_node;
#endif

	gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
	if (gdev->id < 0) {
		ret = gdev->id;
		goto err_free_gdev;
	}
	dev_set_name(&gdev->dev, "gpiochip%d", gdev->id);
	device_initialize(&gdev->dev);
	dev_set_drvdata(&gdev->dev, gdev);
	if (chip->parent && chip->parent->driver)
		gdev->owner = chip->parent->driver->owner;
	else if (chip->owner)
		/* TODO: remove chip->owner */
		gdev->owner = chip->owner;
	else
		gdev->owner = THIS_MODULE;

	gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
	if (!gdev->descs) {
		ret = -ENOMEM;
		goto err_free_ida;
	}

	if (chip->ngpio == 0) {
		chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
		ret = -EINVAL;
		goto err_free_descs;
	}

	if (chip->ngpio > FASTPATH_NGPIO)
		chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
		chip->ngpio, FASTPATH_NGPIO);

	gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
	if (!gdev->label) {
		ret = -ENOMEM;
		goto err_free_descs;
	}

	gdev->ngpio = chip->ngpio;
	gdev->data = data;

	spin_lock_irqsave(&gpio_lock, flags);

	/*
	 * TODO: this allocates a Linux GPIO number base in the global
	 * GPIO numberspace for this chip. In the long run we want to
	 * get *rid* of this numberspace and use only descriptors, but
	 * it may be a pipe dream. It will not happen before we get rid
	 * of the sysfs interface anyways.
	 */
	if (base < 0) {
		base = gpiochip_find_base(chip->ngpio);
		if (base < 0) {
			ret = base;
			spin_unlock_irqrestore(&gpio_lock, flags);
			goto err_free_label;
		}
		/*
		 * TODO: it should not be necessary to reflect the assigned
		 * base outside of the GPIO subsystem. Go over drivers and
		 * see if anyone makes use of this, else drop this and assign
		 * a poison instead.
		 */
		chip->base = base;
	}
	gdev->base = base;

	ret = gpiodev_add_to_list(gdev);
	if (ret) {
		spin_unlock_irqrestore(&gpio_lock, flags);
		goto err_free_label;
	}

	spin_unlock_irqrestore(&gpio_lock, flags);

	for (i = 0; i < chip->ngpio; i++)
		gdev->descs[i].gdev = gdev;

#ifdef CONFIG_PINCTRL
	INIT_LIST_HEAD(&gdev->pin_ranges);
#endif

	ret = gpiochip_set_desc_names(chip);
	if (ret)
		goto err_remove_from_list;

	ret = gpiochip_alloc_valid_mask(chip);
	if (ret)
		goto err_remove_from_list;

	ret = of_gpiochip_add(chip);
	if (ret)
		goto err_free_gpiochip_mask;

	ret = gpiochip_init_valid_mask(chip);
	if (ret)
		goto err_remove_of_chip;

	for (i = 0; i < chip->ngpio; i++) {
		struct gpio_desc *desc = &gdev->descs[i];

		if (chip->get_direction && gpiochip_line_is_valid(chip, i)) {
			if (!chip->get_direction(chip, i))
				set_bit(FLAG_IS_OUT, &desc->flags);
			else
				clear_bit(FLAG_IS_OUT, &desc->flags);
		} else {
			if (!chip->direction_input)
				set_bit(FLAG_IS_OUT, &desc->flags);
			else
				clear_bit(FLAG_IS_OUT, &desc->flags);
		}
	}

	ret = gpiochip_add_pin_ranges(chip);
	if (ret)
		goto err_remove_of_chip;

	acpi_gpiochip_add(chip);

	machine_gpiochip_add(chip);

	ret = gpiochip_irqchip_init_valid_mask(chip);
	if (ret)
		goto err_remove_acpi_chip;

	ret = gpiochip_irqchip_init_hw(chip);
	if (ret)
		goto err_remove_acpi_chip;

	ret = gpiochip_add_irqchip(chip, lock_key, request_key);
	if (ret)
		goto err_remove_irqchip_mask;

	/*
	 * By first adding the chardev, and then adding the device,
	 * we get a device node entry in sysfs under
	 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for
	 * coldplug of device nodes and other udev business.
	 * We can do this only if gpiolib has been initialized.
	 * Otherwise, defer until later.
	 */
	if (gpiolib_initialized) {
		ret = gpiochip_setup_dev(gdev);
		if (ret)
			goto err_remove_irqchip;
	}
	return 0;

err_remove_irqchip:
	gpiochip_irqchip_remove(chip);
err_remove_irqchip_mask:
	gpiochip_irqchip_free_valid_mask(chip);
err_remove_acpi_chip:
	acpi_gpiochip_remove(chip);
err_remove_of_chip:
	gpiochip_free_hogs(chip);
	of_gpiochip_remove(chip);
err_free_gpiochip_mask:
	gpiochip_remove_pin_ranges(chip);
	gpiochip_free_valid_mask(chip);
err_remove_from_list:
	spin_lock_irqsave(&gpio_lock, flags);
	list_del(&gdev->list);
	spin_unlock_irqrestore(&gpio_lock, flags);
err_free_label:
	kfree_const(gdev->label);
err_free_descs:
	kfree(gdev->descs);
err_free_ida:
	ida_simple_remove(&gpio_ida, gdev->id);
err_free_gdev:
	/* failures here can mean systems won't boot... */
	pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
	       gdev->base, gdev->base + gdev->ngpio - 1,
	       chip->label ? : "generic", ret);
	kfree(gdev);
	return ret;
}
EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);

/**
 * gpiochip_get_data() - get per-subdriver data for the chip
 * @chip: GPIO chip
 *
 * Returns:
 * The per-subdriver data for the chip.
 */
void *gpiochip_get_data(struct gpio_chip *chip)
{
	return chip->gpiodev->data;
}
EXPORT_SYMBOL_GPL(gpiochip_get_data);

/**
 * gpiochip_remove() - unregister a gpio_chip
 * @chip: the chip to unregister
 *
 * A gpio_chip with any GPIOs still requested may not be removed.
 */
void gpiochip_remove(struct gpio_chip *chip)
{
	struct gpio_device *gdev = chip->gpiodev;
	struct gpio_desc *desc;
	unsigned long	flags;
	unsigned	i;
	bool		requested = false;

	/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
	gpiochip_sysfs_unregister(gdev);
	gpiochip_free_hogs(chip);
	/* Numb the device, cancelling all outstanding operations */
	gdev->chip = NULL;
	gpiochip_irqchip_remove(chip);
	acpi_gpiochip_remove(chip);
	of_gpiochip_remove(chip);
	gpiochip_remove_pin_ranges(chip);
	gpiochip_free_valid_mask(chip);
	/*
	 * We accept no more calls into the driver from this point, so
	 * NULL the driver data pointer
	 */
	gdev->data = NULL;

	spin_lock_irqsave(&gpio_lock, flags);
	for (i = 0; i < gdev->ngpio; i++) {
		desc = &gdev->descs[i];
		if (test_bit(FLAG_REQUESTED, &desc->flags))
			requested = true;
	}
	spin_unlock_irqrestore(&gpio_lock, flags);

	if (requested)
		dev_crit(&gdev->dev,
			 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");

	/*
	 * The gpiochip side puts its use of the device to rest here:
	 * if there are no userspace clients, the chardev and device will
	 * be removed, else it will be dangling until the last user is
	 * gone.
	 */
	cdev_device_del(&gdev->chrdev, &gdev->dev);
	put_device(&gdev->dev);
}
EXPORT_SYMBOL_GPL(gpiochip_remove);

static void devm_gpio_chip_release(struct device *dev, void *res)
{
	struct gpio_chip *chip = *(struct gpio_chip **)res;

	gpiochip_remove(chip);
}

/**
 * devm_gpiochip_add_data() - Resource managed gpiochip_add_data()
 * @dev: pointer to the device that gpio_chip belongs to.
 * @chip: the chip to register, with chip->base initialized
 * @data: driver-private data associated with this chip
 *
 * Context: potentially before irqs will work
 *
 * The gpio chip automatically be released when the device is unbound.
 *
 * Returns:
 * A negative errno if the chip can't be registered, such as because the
 * chip->base is invalid or already associated with a different chip.
 * Otherwise it returns zero as a success code.
 */
int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip,
			   void *data)
{
	struct gpio_chip **ptr;
	int ret;

	ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
			     GFP_KERNEL);
	if (!ptr)
		return -ENOMEM;

	ret = gpiochip_add_data(chip, data);
	if (ret < 0) {
		devres_free(ptr);
		return ret;
	}

	*ptr = chip;
	devres_add(dev, ptr);

	return 0;
}
EXPORT_SYMBOL_GPL(devm_gpiochip_add_data);

/**
 * gpiochip_find() - iterator for locating a specific gpio_chip
 * @data: data to pass to match function
 * @match: Callback function to check gpio_chip
 *
 * Similar to bus_find_device.  It returns a reference to a gpio_chip as
 * determined by a user supplied @match callback.  The callback should return
 * 0 if the device doesn't match and non-zero if it does.  If the callback is
 * non-zero, this function will return to the caller and not iterate over any
 * more gpio_chips.
 */
struct gpio_chip *gpiochip_find(void *data,
				int (*match)(struct gpio_chip *chip,
					     void *data))
{
	struct gpio_device *gdev;
	struct gpio_chip *chip = NULL;
	unsigned long flags;

	spin_lock_irqsave(&gpio_lock, flags);
	list_for_each_entry(gdev, &gpio_devices, list)
		if (gdev->chip && match(gdev->chip, data)) {
			chip = gdev->chip;
			break;
		}

	spin_unlock_irqrestore(&gpio_lock, flags);

	return chip;
}
EXPORT_SYMBOL_GPL(gpiochip_find);

static int gpiochip_match_name(struct gpio_chip *chip, void *data)
{
	const char *name = data;

	return !strcmp(chip->label, name);
}

static struct gpio_chip *find_chip_by_name(const char *name)
{
	return gpiochip_find((void *)name, gpiochip_match_name);
}

#ifdef CONFIG_GPIOLIB_IRQCHIP

/*
 * The following is irqchip helper code for gpiochips.
 */

static int gpiochip_irqchip_init_hw(struct gpio_chip *gc)
{
	struct gpio_irq_chip *girq = &gc->irq;

	if (!girq->init_hw)
		return 0;

	return girq->init_hw(gc);
}

static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
{
	struct gpio_irq_chip *girq = &gc->irq;

	if (!girq->init_valid_mask)
		return 0;

	girq->valid_mask = gpiochip_allocate_mask(gc);
	if (!girq->valid_mask)
		return -ENOMEM;

	girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);

	return 0;
}

static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
{
	bitmap_free(gpiochip->irq.valid_mask);
	gpiochip->irq.valid_mask = NULL;
}

bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip,
				unsigned int offset)
{
	if (!gpiochip_line_is_valid(gpiochip, offset))
		return false;
	/* No mask means all valid */
	if (likely(!gpiochip->irq.valid_mask))
		return true;
	return test_bit(offset, gpiochip->irq.valid_mask);
}
EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid);

/**
 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip
 * @gc: the gpiochip to set the irqchip chain to
 * @parent_irq: the irq number corresponding to the parent IRQ for this
 * chained irqchip
 * @parent_handler: the parent interrupt handler for the accumulated IRQ
 * coming out of the gpiochip. If the interrupt is nested rather than
 * cascaded, pass NULL in this handler argument
 */
static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc,
					  unsigned int parent_irq,
					  irq_flow_handler_t parent_handler)
{
	struct gpio_irq_chip *girq = &gc->irq;
	struct device *dev = &gc->gpiodev->dev;

	if (!girq->domain) {
		chip_err(gc, "called %s before setting up irqchip\n",
			 __func__);
		return;
	}

	if (parent_handler) {
		if (gc->can_sleep) {
			chip_err(gc,
				 "you cannot have chained interrupts on a chip that may sleep\n");
			return;
		}
		girq->parents = devm_kcalloc(dev, 1,
					     sizeof(*girq->parents),
					     GFP_KERNEL);
		if (!girq->parents) {
			chip_err(gc, "out of memory allocating parent IRQ\n");
			return;
		}
		girq->parents[0] = parent_irq;
		girq->num_parents = 1;
		/*
		 * The parent irqchip is already using the chip_data for this
		 * irqchip, so our callbacks simply use the handler_data.
		 */
		irq_set_chained_handler_and_data(parent_irq, parent_handler,
						 gc);
	}
}

/**
 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip
 * @gpiochip: the gpiochip to set the irqchip chain to
 * @irqchip: the irqchip to chain to the gpiochip
 * @parent_irq: the irq number corresponding to the parent IRQ for this
 * chained irqchip
 * @parent_handler: the parent interrupt handler for the accumulated IRQ
 * coming out of the gpiochip.
 */
void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
				  struct irq_chip *irqchip,
				  unsigned int parent_irq,
				  irq_flow_handler_t parent_handler)
{
	if (gpiochip->irq.threaded) {
		chip_err(gpiochip, "tried to chain a threaded gpiochip\n");
		return;
	}

	gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler);
}
EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);

/**
 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip
 * @gpiochip: the gpiochip to set the irqchip nested handler to
 * @irqchip: the irqchip to nest to the gpiochip
 * @parent_irq: the irq number corresponding to the parent IRQ for this
 * nested irqchip
 */
void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip,
				 struct irq_chip *irqchip,
				 unsigned int parent_irq)
{
	gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL);
}
EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip);

#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY

/**
 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip
 * to a gpiochip
 * @gc: the gpiochip to set the irqchip hierarchical handler to
 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt
 * will then percolate up to the parent
 */
static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
					      struct irq_chip *irqchip)
{
	/* DT will deal with mapping each IRQ as we go along */
	if (is_of_node(gc->irq.fwnode))
		return;

	/*
	 * This is for legacy and boardfile "irqchip" fwnodes: allocate
	 * irqs upfront instead of dynamically since we don't have the
	 * dynamic type of allocation that hardware description languages
	 * provide. Once all GPIO drivers using board files are gone from
	 * the kernel we can delete this code, but for a transitional period
	 * it is necessary to keep this around.
	 */
	if (is_fwnode_irqchip(gc->irq.fwnode)) {
		int i;
		int ret;

		for (i = 0; i < gc->ngpio; i++) {
			struct irq_fwspec fwspec;
			unsigned int parent_hwirq;
			unsigned int parent_type;
			struct gpio_irq_chip *girq = &gc->irq;

			/*
			 * We call the child to parent translation function
			 * only to check if the child IRQ is valid or not.
			 * Just pick the rising edge type here as that is what
			 * we likely need to support.
			 */
			ret = girq->child_to_parent_hwirq(gc, i,
							  IRQ_TYPE_EDGE_RISING,
							  &parent_hwirq,
							  &parent_type);
			if (ret) {
				chip_err(gc, "skip set-up on hwirq %d\n",
					 i);
				continue;
			}

			fwspec.fwnode = gc->irq.fwnode;
			/* This is the hwirq for the GPIO line side of things */
			fwspec.param[0] = girq->child_offset_to_irq(gc, i);
			/* Just pick something */
			fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
			fwspec.param_count = 2;
			ret = __irq_domain_alloc_irqs(gc->irq.domain,
						      /* just pick something */
						      -1,
						      1,
						      NUMA_NO_NODE,
						      &fwspec,
						      false,
						      NULL);
			if (ret < 0) {
				chip_err(gc,
					 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n",
					 i, parent_hwirq,
					 ret);
			}
		}
	}

	chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__);

	return;
}

static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d,
						   struct irq_fwspec *fwspec,
						   unsigned long *hwirq,
						   unsigned int *type)
{
	/* We support standard DT translation */
	if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) {
		return irq_domain_translate_twocell(d, fwspec, hwirq, type);
	}

	/* This is for board files and others not using DT */
	if (is_fwnode_irqchip(fwspec->fwnode)) {
		int ret;

		ret = irq_domain_translate_twocell(d, fwspec, hwirq, type);
		if (ret)
			return ret;
		WARN_ON(*type == IRQ_TYPE_NONE);
		return 0;
	}
	return -EINVAL;
}

static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d,
					       unsigned int irq,
					       unsigned int nr_irqs,
					       void *data)
{
	struct gpio_chip *gc = d->host_data;
	irq_hw_number_t hwirq;
	unsigned int type = IRQ_TYPE_NONE;
	struct irq_fwspec *fwspec = data;
	struct irq_fwspec parent_fwspec;
	unsigned int parent_hwirq;
	unsigned int parent_type;
	struct gpio_irq_chip *girq = &gc->irq;
	int ret;

	/*
	 * The nr_irqs parameter is always one except for PCI multi-MSI
	 * so this should not happen.
	 */
	WARN_ON(nr_irqs != 1);

	ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type);
	if (ret)
		return ret;

	chip_info(gc, "allocate IRQ %d, hwirq %lu\n", irq,  hwirq);

	ret = girq->child_to_parent_hwirq(gc, hwirq, type,
					  &parent_hwirq, &parent_type);
	if (ret) {
		chip_err(gc, "can't look up hwirq %lu\n", hwirq);
		return ret;
	}
	chip_info(gc, "found parent hwirq %u\n", parent_hwirq);

	/*
	 * We set handle_bad_irq because the .set_type() should
	 * always be invoked and set the right type of handler.
	 */
	irq_domain_set_info(d,
			    irq,
			    hwirq,
			    gc->irq.chip,
			    gc,
			    girq->handler,
			    NULL, NULL);
	irq_set_probe(irq);

	/*
	 * Create a IRQ fwspec to send up to the parent irqdomain:
	 * specify the hwirq we address on the parent and tie it
	 * all together up the chain.
	 */
	parent_fwspec.fwnode = d->parent->fwnode;
	/* This parent only handles asserted level IRQs */
	girq->populate_parent_fwspec(gc, &parent_fwspec, parent_hwirq,
				     parent_type);
	chip_info(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
		  irq, parent_hwirq);
	ret = irq_domain_alloc_irqs_parent(d, irq, 1, &parent_fwspec);
	if (ret)
		chip_err(gc,
			 "failed to allocate parent hwirq %d for hwirq %lu\n",
			 parent_hwirq, hwirq);

	return ret;
}

static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip,
						      unsigned int offset)
{
	return offset;
}

static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops)
{
	ops->activate = gpiochip_irq_domain_activate;
	ops->deactivate = gpiochip_irq_domain_deactivate;
	ops->alloc = gpiochip_hierarchy_irq_domain_alloc;
	ops->free = irq_domain_free_irqs_common;

	/*
	 * We only allow overriding the translate() function for
	 * hierarchical chips, and this should only be done if the user
	 * really need something other than 1:1 translation.
	 */
	if (!ops->translate)
		ops->translate = gpiochip_hierarchy_irq_domain_translate;
}

static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
{
	if (!gc->irq.child_to_parent_hwirq ||
	    !gc->irq.fwnode) {
		chip_err(gc, "missing irqdomain vital data\n");
		return -EINVAL;
	}

	if (!gc->irq.child_offset_to_irq)
		gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop;

	if (!gc->irq.populate_parent_fwspec)
		gc->irq.populate_parent_fwspec =
			gpiochip_populate_parent_fwspec_twocell;

	gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops);

	gc->irq.domain = irq_domain_create_hierarchy(
		gc->irq.parent_domain,
		0,
		gc->ngpio,
		gc->irq.fwnode,
		&gc->irq.child_irq_domain_ops,
		gc);

	if (!gc->irq.domain)
		return -ENOMEM;

	gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip);

	return 0;
}

static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
{
	return !!gc->irq.parent_domain;
}

void gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip,
					     struct irq_fwspec *fwspec,
					     unsigned int parent_hwirq,
					     unsigned int parent_type)
{
	fwspec->param_count = 2;
	fwspec->param[0] = parent_hwirq;
	fwspec->param[1] = parent_type;
}
EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);

void gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip,
					      struct irq_fwspec *fwspec,
					      unsigned int parent_hwirq,
					      unsigned int parent_type)
{
	fwspec->param_count = 4;
	fwspec->param[0] = 0;
	fwspec->param[1] = parent_hwirq;
	fwspec->param[2] = 0;
	fwspec->param[3] = parent_type;
}
EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell);

#else

static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc)
{
	return -EINVAL;
}

static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc)
{
	return false;
}

#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */

/**
 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
 * @d: the irqdomain used by this irqchip
 * @irq: the global irq number used by this GPIO irqchip irq
 * @hwirq: the local IRQ/GPIO line offset on this gpiochip
 *
 * This function will set up the mapping for a certain IRQ line on a
 * gpiochip by assigning the gpiochip as chip data, and using the irqchip
 * stored inside the gpiochip.
 */
int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
		     irq_hw_number_t hwirq)
{
	struct gpio_chip *chip = d->host_data;
	int ret = 0;

	if (!gpiochip_irqchip_irq_valid(chip, hwirq))
		return -ENXIO;

	irq_set_chip_data(irq, chip);
	/*
	 * This lock class tells lockdep that GPIO irqs are in a different
	 * category than their parents, so it won't report false recursion.
	 */
	irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key);
	irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler);
	/* Chips that use nested thread handlers have them marked */
	if (chip->irq.threaded)
		irq_set_nested_thread(irq, 1);
	irq_set_noprobe(irq);

	if (chip->irq.num_parents == 1)
		ret = irq_set_parent(irq, chip->irq.parents[0]);
	else if (chip->irq.map)
		ret = irq_set_parent(irq, chip->irq.map[hwirq]);

	if (ret < 0)
		return ret;

	/*
	 * No set-up of the hardware will happen if IRQ_TYPE_NONE
	 * is passed as default type.
	 */
	if (chip->irq.default_type != IRQ_TYPE_NONE)
		irq_set_irq_type(irq, chip->irq.default_type);

	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_irq_map);

void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
{
	struct gpio_chip *chip = d->host_data;

	if (chip->irq.threaded)
		irq_set_nested_thread(irq, 0);
	irq_set_chip_and_handler(irq, NULL, NULL);
	irq_set_chip_data(irq, NULL);
}
EXPORT_SYMBOL_GPL(gpiochip_irq_unmap);

static const struct irq_domain_ops gpiochip_domain_ops = {
	.map	= gpiochip_irq_map,
	.unmap	= gpiochip_irq_unmap,
	/* Virtually all GPIO irqchips are twocell:ed */
	.xlate	= irq_domain_xlate_twocell,
};

/*
 * TODO: move these activate/deactivate in under the hierarchicial
 * irqchip implementation as static once SPMI and SSBI (all external
 * users) are phased over.
 */
/**
 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ
 * @domain: The IRQ domain used by this IRQ chip
 * @data: Outermost irq_data associated with the IRQ
 * @reserve: If set, only reserve an interrupt vector instead of assigning one
 *
 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be
 * used as the activate function for the &struct irq_domain_ops. The host_data
 * for the IRQ domain must be the &struct gpio_chip.
 */
int gpiochip_irq_domain_activate(struct irq_domain *domain,
				 struct irq_data *data, bool reserve)
{
	struct gpio_chip *chip = domain->host_data;

	return gpiochip_lock_as_irq(chip, data->hwirq);
}
EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate);

/**
 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ
 * @domain: The IRQ domain used by this IRQ chip
 * @data: Outermost irq_data associated with the IRQ
 *
 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to
 * be used as the deactivate function for the &struct irq_domain_ops. The
 * host_data for the IRQ domain must be the &struct gpio_chip.
 */
void gpiochip_irq_domain_deactivate(struct irq_domain *domain,
				    struct irq_data *data)
{
	struct gpio_chip *chip = domain->host_data;

	return gpiochip_unlock_as_irq(chip, data->hwirq);
}
EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate);

static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
{
	struct irq_domain *domain = chip->irq.domain;

	if (!gpiochip_irqchip_irq_valid(chip, offset))
		return -ENXIO;

#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
	if (irq_domain_is_hierarchy(domain)) {
		struct irq_fwspec spec;

		spec.fwnode = domain->fwnode;
		spec.param_count = 2;
		spec.param[0] = chip->irq.child_offset_to_irq(chip, offset);
		spec.param[1] = IRQ_TYPE_NONE;

		return irq_create_fwspec_mapping(&spec);
	}
#endif

	return irq_create_mapping(domain, offset);
}

static int gpiochip_irq_reqres(struct irq_data *d)
{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);

	return gpiochip_reqres_irq(chip, d->hwirq);
}

static void gpiochip_irq_relres(struct irq_data *d)
{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);

	gpiochip_relres_irq(chip, d->hwirq);
}

static void gpiochip_irq_enable(struct irq_data *d)
{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);

	gpiochip_enable_irq(chip, d->hwirq);
	if (chip->irq.irq_enable)
		chip->irq.irq_enable(d);
	else
		chip->irq.chip->irq_unmask(d);
}

static void gpiochip_irq_disable(struct irq_data *d)
{
	struct gpio_chip *chip = irq_data_get_irq_chip_data(d);

	if (chip->irq.irq_disable)
		chip->irq.irq_disable(d);
	else
		chip->irq.chip->irq_mask(d);
	gpiochip_disable_irq(chip, d->hwirq);
}

static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip)
{
	struct irq_chip *irqchip = gpiochip->irq.chip;

	if (!irqchip->irq_request_resources &&
	    !irqchip->irq_release_resources) {
		irqchip->irq_request_resources = gpiochip_irq_reqres;
		irqchip->irq_release_resources = gpiochip_irq_relres;
	}
	if (WARN_ON(gpiochip->irq.irq_enable))
		return;
	/* Check if the irqchip already has this hook... */
	if (irqchip->irq_enable == gpiochip_irq_enable) {
		/*
		 * ...and if so, give a gentle warning that this is bad
		 * practice.
		 */
		chip_info(gpiochip,
			  "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
		return;
	}
	gpiochip->irq.irq_enable = irqchip->irq_enable;
	gpiochip->irq.irq_disable = irqchip->irq_disable;
	irqchip->irq_enable = gpiochip_irq_enable;
	irqchip->irq_disable = gpiochip_irq_disable;
}

/**
 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
 * @gpiochip: the GPIO chip to add the IRQ chip to
 * @lock_key: lockdep class for IRQ lock
 * @request_key: lockdep class for IRQ request
 */
static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
				struct lock_class_key *lock_key,
				struct lock_class_key *request_key)
{
	struct irq_chip *irqchip = gpiochip->irq.chip;
	const struct irq_domain_ops *ops = NULL;
	struct device_node *np;
	unsigned int type;
	unsigned int i;

	if (!irqchip)
		return 0;

	if (gpiochip->irq.parent_handler && gpiochip->can_sleep) {
		chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n");
		return -EINVAL;
	}

	np = gpiochip->gpiodev->dev.of_node;
	type = gpiochip->irq.default_type;

	/*
	 * Specifying a default trigger is a terrible idea if DT or ACPI is
	 * used to configure the interrupts, as you may end up with
	 * conflicting triggers. Tell the user, and reset to NONE.
	 */
	if (WARN(np && type != IRQ_TYPE_NONE,
		 "%s: Ignoring %u default trigger\n", np->full_name, type))
		type = IRQ_TYPE_NONE;

	if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
		acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
				 "Ignoring %u default trigger\n", type);
		type = IRQ_TYPE_NONE;
	}

	gpiochip->to_irq = gpiochip_to_irq;
	gpiochip->irq.default_type = type;
	gpiochip->irq.lock_key = lock_key;
	gpiochip->irq.request_key = request_key;

	/* If a parent irqdomain is provided, let's build a hierarchy */
	if (gpiochip_hierarchy_is_hierarchical(gpiochip)) {
		int ret = gpiochip_hierarchy_add_domain(gpiochip);
		if (ret)
			return ret;
	} else {
		/* Some drivers provide custom irqdomain ops */
		if (gpiochip->irq.domain_ops)
			ops = gpiochip->irq.domain_ops;

		if (!ops)
			ops = &gpiochip_domain_ops;
		gpiochip->irq.domain = irq_domain_add_simple(np,
			gpiochip->ngpio,
			gpiochip->irq.first,
			ops, gpiochip);
		if (!gpiochip->irq.domain)
			return -EINVAL;
	}

	if (gpiochip->irq.parent_handler) {
		void *data = gpiochip->irq.parent_handler_data ?: gpiochip;

		for (i = 0; i < gpiochip->irq.num_parents; i++) {
			/*
			 * The parent IRQ chip is already using the chip_data
			 * for this IRQ chip, so our callbacks simply use the
			 * handler_data.
			 */
			irq_set_chained_handler_and_data(gpiochip->irq.parents[i],
							 gpiochip->irq.parent_handler,
							 data);
		}
	}

	gpiochip_set_irq_hooks(gpiochip);

	acpi_gpiochip_request_interrupts(gpiochip);

	return 0;
}

/**
 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip
 * @gpiochip: the gpiochip to remove the irqchip from
 *
 * This is called only from gpiochip_remove()
 */
static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
{
	struct irq_chip *irqchip = gpiochip->irq.chip;
	unsigned int offset;

	acpi_gpiochip_free_interrupts(gpiochip);

	if (irqchip && gpiochip->irq.parent_handler) {
		struct gpio_irq_chip *irq = &gpiochip->irq;
		unsigned int i;

		for (i = 0; i < irq->num_parents; i++)
			irq_set_chained_handler_and_data(irq->parents[i],
							 NULL, NULL);
	}

	/* Remove all IRQ mappings and delete the domain */
	if (gpiochip->irq.domain) {
		unsigned int irq;

		for (offset = 0; offset < gpiochip->ngpio; offset++) {
			if (!gpiochip_irqchip_irq_valid(gpiochip, offset))
				continue;

			irq = irq_find_mapping(gpiochip->irq.domain, offset);
			irq_dispose_mapping(irq);
		}

		irq_domain_remove(gpiochip->irq.domain);
	}

	if (irqchip) {
		if (irqchip->irq_request_resources == gpiochip_irq_reqres) {
			irqchip->irq_request_resources = NULL;
			irqchip->irq_release_resources = NULL;
		}
		if (irqchip->irq_enable == gpiochip_irq_enable) {
			irqchip->irq_enable = gpiochip->irq.irq_enable;
			irqchip->irq_disable = gpiochip->irq.irq_disable;
		}
	}
	gpiochip->irq.irq_enable = NULL;
	gpiochip->irq.irq_disable = NULL;
	gpiochip->irq.chip = NULL;

	gpiochip_irqchip_free_valid_mask(gpiochip);
}

/**
 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
 * @gpiochip: the gpiochip to add the irqchip to
 * @irqchip: the irqchip to add to the gpiochip
 * @first_irq: if not dynamically assigned, the base (first) IRQ to
 * allocate gpiochip irqs from
 * @handler: the irq handler to use (often a predefined irq core function)
 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
 * to have the core avoid setting up any default type in the hardware.
 * @threaded: whether this irqchip uses a nested thread handler
 * @lock_key: lockdep class for IRQ lock
 * @request_key: lockdep class for IRQ request
 *
 * This function closely associates a certain irqchip with a certain
 * gpiochip, providing an irq domain to translate the local IRQs to
 * global irqs in the gpiolib core, and making sure that the gpiochip
 * is passed as chip data to all related functions. Driver callbacks
 * need to use gpiochip_get_data() to get their local state containers back
 * from the gpiochip passed as chip data. An irqdomain will be stored
 * in the gpiochip that shall be used by the driver to handle IRQ number
 * translation. The gpiochip will need to be initialized and registered
 * before calling this function.
 *
 * This function will handle two cell:ed simple IRQs and assumes all
 * the pins on the gpiochip can generate a unique IRQ. Everything else
 * need to be open coded.
 */
int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
			     struct irq_chip *irqchip,
			     unsigned int first_irq,
			     irq_flow_handler_t handler,
			     unsigned int type,
			     bool threaded,
			     struct lock_class_key *lock_key,
			     struct lock_class_key *request_key)
{
	struct device_node *of_node;

	if (!gpiochip || !irqchip)
		return -EINVAL;

	if (!gpiochip->parent) {
		pr_err("missing gpiochip .dev parent pointer\n");
		return -EINVAL;
	}
	gpiochip->irq.threaded = threaded;
	of_node = gpiochip->parent->of_node;
#ifdef CONFIG_OF_GPIO
	/*
	 * If the gpiochip has an assigned OF node this takes precedence
	 * FIXME: get rid of this and use gpiochip->parent->of_node
	 * everywhere
	 */
	if (gpiochip->of_node)
		of_node = gpiochip->of_node;
#endif
	/*
	 * Specifying a default trigger is a terrible idea if DT or ACPI is
	 * used to configure the interrupts, as you may end-up with
	 * conflicting triggers. Tell the user, and reset to NONE.
	 */
	if (WARN(of_node && type != IRQ_TYPE_NONE,
		 "%pOF: Ignoring %d default trigger\n", of_node, type))
		type = IRQ_TYPE_NONE;
	if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) {
		acpi_handle_warn(ACPI_HANDLE(gpiochip->parent),
				 "Ignoring %d default trigger\n", type);
		type = IRQ_TYPE_NONE;
	}

	gpiochip->irq.chip = irqchip;
	gpiochip->irq.handler = handler;
	gpiochip->irq.default_type = type;
	gpiochip->to_irq = gpiochip_to_irq;
	gpiochip->irq.lock_key = lock_key;
	gpiochip->irq.request_key = request_key;
	gpiochip->irq.domain = irq_domain_add_simple(of_node,
					gpiochip->ngpio, first_irq,
					&gpiochip_domain_ops, gpiochip);
	if (!gpiochip->irq.domain) {
		gpiochip->irq.chip = NULL;
		return -EINVAL;
	}

	gpiochip_set_irq_hooks(gpiochip);

	acpi_gpiochip_request_interrupts(gpiochip);

	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);

#else /* CONFIG_GPIOLIB_IRQCHIP */

static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
				       struct lock_class_key *lock_key,
				       struct lock_class_key *request_key)
{
	return 0;
}
static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}

static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip)
{
	return 0;
}

static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
{
	return 0;
}
static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip)
{ }

#endif /* CONFIG_GPIOLIB_IRQCHIP */

/**
 * gpiochip_generic_request() - request the gpio function for a pin
 * @chip: the gpiochip owning the GPIO
 * @offset: the offset of the GPIO to request for GPIO function
 */
int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
{
	return pinctrl_gpio_request(chip->gpiodev->base + offset);
}
EXPORT_SYMBOL_GPL(gpiochip_generic_request);

/**
 * gpiochip_generic_free() - free the gpio function from a pin
 * @chip: the gpiochip to request the gpio function for
 * @offset: the offset of the GPIO to free from GPIO function
 */
void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
{
	pinctrl_gpio_free(chip->gpiodev->base + offset);
}
EXPORT_SYMBOL_GPL(gpiochip_generic_free);

/**
 * gpiochip_generic_config() - apply configuration for a pin
 * @chip: the gpiochip owning the GPIO
 * @offset: the offset of the GPIO to apply the configuration
 * @config: the configuration to be applied
 */
int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset,
			    unsigned long config)
{
	return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config);
}
EXPORT_SYMBOL_GPL(gpiochip_generic_config);

#ifdef CONFIG_PINCTRL

/**
 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
 * @chip: the gpiochip to add the range for
 * @pctldev: the pin controller to map to
 * @gpio_offset: the start offset in the current gpio_chip number space
 * @pin_group: name of the pin group inside the pin controller
 *
 * Calling this function directly from a DeviceTree-supported
 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
 */
int gpiochip_add_pingroup_range(struct gpio_chip *chip,
			struct pinctrl_dev *pctldev,
			unsigned int gpio_offset, const char *pin_group)
{
	struct gpio_pin_range *pin_range;
	struct gpio_device *gdev = chip->gpiodev;
	int ret;

	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
	if (!pin_range) {
		chip_err(chip, "failed to allocate pin ranges\n");
		return -ENOMEM;
	}

	/* Use local offset as range ID */
	pin_range->range.id = gpio_offset;
	pin_range->range.gc = chip;
	pin_range->range.name = chip->label;
	pin_range->range.base = gdev->base + gpio_offset;
	pin_range->pctldev = pctldev;

	ret = pinctrl_get_group_pins(pctldev, pin_group,
					&pin_range->range.pins,
					&pin_range->range.npins);
	if (ret < 0) {
		kfree(pin_range);
		return ret;
	}

	pinctrl_add_gpio_range(pctldev, &pin_range->range);

	chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n",
		 gpio_offset, gpio_offset + pin_range->range.npins - 1,
		 pinctrl_dev_get_devname(pctldev), pin_group);

	list_add_tail(&pin_range->node, &gdev->pin_ranges);

	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range);

/**
 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping
 * @chip: the gpiochip to add the range for
 * @pinctl_name: the dev_name() of the pin controller to map to
 * @gpio_offset: the start offset in the current gpio_chip number space
 * @pin_offset: the start offset in the pin controller number space
 * @npins: the number of pins from the offset of each pin space (GPIO and
 *	pin controller) to accumulate in this range
 *
 * Returns:
 * 0 on success, or a negative error-code on failure.
 *
 * Calling this function directly from a DeviceTree-supported
 * pinctrl driver is DEPRECATED. Please see Section 2.1 of
 * Documentation/devicetree/bindings/gpio/gpio.txt on how to
 * bind pinctrl and gpio drivers via the "gpio-ranges" property.
 */
int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
			   unsigned int gpio_offset, unsigned int pin_offset,
			   unsigned int npins)
{
	struct gpio_pin_range *pin_range;
	struct gpio_device *gdev = chip->gpiodev;
	int ret;

	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
	if (!pin_range) {
		chip_err(chip, "failed to allocate pin ranges\n");
		return -ENOMEM;
	}

	/* Use local offset as range ID */
	pin_range->range.id = gpio_offset;
	pin_range->range.gc = chip;
	pin_range->range.name = chip->label;
	pin_range->range.base = gdev->base + gpio_offset;
	pin_range->range.pin_base = pin_offset;
	pin_range->range.npins = npins;
	pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
			&pin_range->range);
	if (IS_ERR(pin_range->pctldev)) {
		ret = PTR_ERR(pin_range->pctldev);
		chip_err(chip, "could not create pin range\n");
		kfree(pin_range);
		return ret;
	}
	chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n",
		 gpio_offset, gpio_offset + npins - 1,
		 pinctl_name,
		 pin_offset, pin_offset + npins - 1);

	list_add_tail(&pin_range->node, &gdev->pin_ranges);

	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_add_pin_range);

/**
 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings
 * @chip: the chip to remove all the mappings for
 */
void gpiochip_remove_pin_ranges(struct gpio_chip *chip)
{
	struct gpio_pin_range *pin_range, *tmp;
	struct gpio_device *gdev = chip->gpiodev;

	list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) {
		list_del(&pin_range->node);
		pinctrl_remove_gpio_range(pin_range->pctldev,
				&pin_range->range);
		kfree(pin_range);
	}
}
EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);

#endif /* CONFIG_PINCTRL */

/* These "optional" allocation calls help prevent drivers from stomping
 * on each other, and help provide better diagnostics in debugfs.
 * They're called even less than the "set direction" calls.
 */
static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
{
	struct gpio_chip	*chip = desc->gdev->chip;
	int			ret;
	unsigned long		flags;
	unsigned		offset;

	if (label) {
		label = kstrdup_const(label, GFP_KERNEL);
		if (!label)
			return -ENOMEM;
	}

	spin_lock_irqsave(&gpio_lock, flags);

	/* NOTE:  gpio_request() can be called in early boot,
	 * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
	 */

	if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) {
		desc_set_label(desc, label ? : "?");
		ret = 0;
	} else {
		kfree_const(label);
		ret = -EBUSY;
		goto done;
	}

	if (chip->request) {
		/* chip->request may sleep */
		spin_unlock_irqrestore(&gpio_lock, flags);
		offset = gpio_chip_hwgpio(desc);
		if (gpiochip_line_is_valid(chip, offset))
			ret = chip->request(chip, offset);
		else
			ret = -EINVAL;
		spin_lock_irqsave(&gpio_lock, flags);

		if (ret < 0) {
			desc_set_label(desc, NULL);
			kfree_const(label);
			clear_bit(FLAG_REQUESTED, &desc->flags);
			goto done;
		}
	}
	if (chip->get_direction) {
		/* chip->get_direction may sleep */
		spin_unlock_irqrestore(&gpio_lock, flags);
		gpiod_get_direction(desc);
		spin_lock_irqsave(&gpio_lock, flags);
	}
done:
	spin_unlock_irqrestore(&gpio_lock, flags);
	return ret;
}

/*
 * This descriptor validation needs to be inserted verbatim into each
 * function taking a descriptor, so we need to use a preprocessor
 * macro to avoid endless duplication. If the desc is NULL it is an
 * optional GPIO and calls should just bail out.
 */
static int validate_desc(const struct gpio_desc *desc, const char *func)
{
	if (!desc)
		return 0;
	if (IS_ERR(desc)) {
		pr_warn("%s: invalid GPIO (errorpointer)\n", func);
		return PTR_ERR(desc);
	}
	if (!desc->gdev) {
		pr_warn("%s: invalid GPIO (no device)\n", func);
		return -EINVAL;
	}
	if (!desc->gdev->chip) {
		dev_warn(&desc->gdev->dev,
			 "%s: backing chip is gone\n", func);
		return 0;
	}
	return 1;
}

#define VALIDATE_DESC(desc) do { \
	int __valid = validate_desc(desc, __func__); \
	if (__valid <= 0) \
		return __valid; \
	} while (0)

#define VALIDATE_DESC_VOID(desc) do { \
	int __valid = validate_desc(desc, __func__); \
	if (__valid <= 0) \
		return; \
	} while (0)

int gpiod_request(struct gpio_desc *desc, const char *label)
{
	int ret = -EPROBE_DEFER;
	struct gpio_device *gdev;

	VALIDATE_DESC(desc);
	gdev = desc->gdev;

	if (try_module_get(gdev->owner)) {
		ret = gpiod_request_commit(desc, label);
		if (ret < 0)
			module_put(gdev->owner);
		else
			get_device(&gdev->dev);
	}

	if (ret)
		gpiod_dbg(desc, "%s: status %d\n", __func__, ret);

	return ret;
}

static bool gpiod_free_commit(struct gpio_desc *desc)
{
	bool			ret = false;
	unsigned long		flags;
	struct gpio_chip	*chip;

	might_sleep();

	gpiod_unexport(desc);

	spin_lock_irqsave(&gpio_lock, flags);

	chip = desc->gdev->chip;
	if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
		if (chip->free) {
			spin_unlock_irqrestore(&gpio_lock, flags);
			might_sleep_if(chip->can_sleep);
			chip->free(chip, gpio_chip_hwgpio(desc));
			spin_lock_irqsave(&gpio_lock, flags);
		}
		kfree_const(desc->label);
		desc_set_label(desc, NULL);
		clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
		clear_bit(FLAG_REQUESTED, &desc->flags);
		clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
		clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
		clear_bit(FLAG_PULL_UP, &desc->flags);
		clear_bit(FLAG_PULL_DOWN, &desc->flags);
		clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
		clear_bit(FLAG_IS_HOGGED, &desc->flags);
		ret = true;
	}

	spin_unlock_irqrestore(&gpio_lock, flags);
	return ret;
}

void gpiod_free(struct gpio_desc *desc)
{
	if (desc && desc->gdev && gpiod_free_commit(desc)) {
		module_put(desc->gdev->owner);
		put_device(&desc->gdev->dev);
	} else {
		WARN_ON(extra_checks);
	}
}

/**
 * gpiochip_is_requested - return string iff signal was requested
 * @chip: controller managing the signal
 * @offset: of signal within controller's 0..(ngpio - 1) range
 *
 * Returns NULL if the GPIO is not currently requested, else a string.
 * The string returned is the label passed to gpio_request(); if none has been
 * passed it is a meaningless, non-NULL constant.
 *
 * This function is for use by GPIO controller drivers.  The label can
 * help with diagnostics, and knowing that the signal is used as a GPIO
 * can help avoid accidentally multiplexing it to another controller.
 */
const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
{
	struct gpio_desc *desc;

	if (offset >= chip->ngpio)
		return NULL;

	desc = &chip->gpiodev->descs[offset];

	if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
		return NULL;
	return desc->label;
}
EXPORT_SYMBOL_GPL(gpiochip_is_requested);

/**
 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor
 * @chip: GPIO chip
 * @hwnum: hardware number of the GPIO for which to request the descriptor
 * @label: label for the GPIO
 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
 * specify things like line inversion semantics with the machine flags
 * such as GPIO_OUT_LOW
 * @dflags: descriptor request flags for this GPIO or 0 if default, this
 * can be used to specify consumer semantics such as open drain
 *
 * Function allows GPIO chip drivers to request and use their own GPIO
 * descriptors via gpiolib API. Difference to gpiod_request() is that this
 * function will not increase reference count of the GPIO chip module. This
 * allows the GPIO chip module to be unloaded as needed (we assume that the
 * GPIO chip driver handles freeing the GPIOs it has requested).
 *
 * Returns:
 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error
 * code on failure.
 */
struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
					    const char *label,
					    enum gpio_lookup_flags lflags,
					    enum gpiod_flags dflags)
{
	struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
	int ret;

	if (IS_ERR(desc)) {
		chip_err(chip, "failed to get GPIO descriptor\n");
		return desc;
	}

	ret = gpiod_request_commit(desc, label);
	if (ret < 0)
		return ERR_PTR(ret);

	ret = gpiod_configure_flags(desc, label, lflags, dflags);
	if (ret) {
		chip_err(chip, "setup of own GPIO %s failed\n", label);
		gpiod_free_commit(desc);
		return ERR_PTR(ret);
	}

	return desc;
}
EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);

/**
 * gpiochip_free_own_desc - Free GPIO requested by the chip driver
 * @desc: GPIO descriptor to free
 *
 * Function frees the given GPIO requested previously with
 * gpiochip_request_own_desc().
 */
void gpiochip_free_own_desc(struct gpio_desc *desc)
{
	if (desc)
		gpiod_free_commit(desc);
}
EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);

/*
 * Drivers MUST set GPIO direction before making get/set calls.  In
 * some cases this is done in early boot, before IRQs are enabled.
 *
 * As a rule these aren't called more than once (except for drivers
 * using the open-drain emulation idiom) so these are natural places
 * to accumulate extra debugging checks.  Note that we can't (yet)
 * rely on gpio_request() having been called beforehand.
 */

static int gpio_set_config(struct gpio_chip *gc, unsigned offset,
			   enum pin_config_param mode)
{
	unsigned long config;
	unsigned arg;

	switch (mode) {
	case PIN_CONFIG_BIAS_DISABLE:
	case PIN_CONFIG_BIAS_PULL_DOWN:
	case PIN_CONFIG_BIAS_PULL_UP:
		arg = 1;
		break;

	default:
		arg = 0;
	}

	config = PIN_CONF_PACKED(mode, arg);
	return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
}

static int gpio_set_bias(struct gpio_chip *chip, struct gpio_desc *desc)
{
	int bias = 0;
	int ret = 0;

	if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
		bias = PIN_CONFIG_BIAS_DISABLE;
	else if (test_bit(FLAG_PULL_UP, &desc->flags))
		bias = PIN_CONFIG_BIAS_PULL_UP;
	else if (test_bit(FLAG_PULL_DOWN, &desc->flags))
		bias = PIN_CONFIG_BIAS_PULL_DOWN;

	if (bias) {
		ret = gpio_set_config(chip, gpio_chip_hwgpio(desc), bias);
		if (ret != -ENOTSUPP)
			return ret;
	}
	return 0;
}

/**
 * gpiod_direction_input - set the GPIO direction to input
 * @desc:	GPIO to set to input
 *
 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can
 * be called safely on it.
 *
 * Return 0 in case of success, else an error code.
 */
int gpiod_direction_input(struct gpio_desc *desc)
{
	struct gpio_chip	*chip;
	int			ret = 0;

	VALIDATE_DESC(desc);
	chip = desc->gdev->chip;

	/*
	 * It is legal to have no .get() and .direction_input() specified if
	 * the chip is output-only, but you can't specify .direction_input()
	 * and not support the .get() operation, that doesn't make sense.
	 */
	if (!chip->get && chip->direction_input) {
		gpiod_warn(desc,
			   "%s: missing get() but have direction_input()\n",
			   __func__);
		return -EIO;
	}

	/*
	 * If we have a .direction_input() callback, things are simple,
	 * just call it. Else we are some input-only chip so try to check the
	 * direction (if .get_direction() is supported) else we silently
	 * assume we are in input mode after this.
	 */
	if (chip->direction_input) {
		ret = chip->direction_input(chip, gpio_chip_hwgpio(desc));
	} else if (chip->get_direction &&
		  (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) {
		gpiod_warn(desc,
			   "%s: missing direction_input() operation and line is output\n",
			   __func__);
		return -EIO;
	}
	if (ret == 0) {
		clear_bit(FLAG_IS_OUT, &desc->flags);
		ret = gpio_set_bias(chip, desc);
	}

	trace_gpio_direction(desc_to_gpio(desc), 1, ret);

	return ret;
}
EXPORT_SYMBOL_GPL(gpiod_direction_input);

static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
{
	struct gpio_chip *gc = desc->gdev->chip;
	int val = !!value;
	int ret = 0;

	/*
	 * It's OK not to specify .direction_output() if the gpiochip is
	 * output-only, but if there is then not even a .set() operation it
	 * is pretty tricky to drive the output line.
	 */
	if (!gc->set && !gc->direction_output) {
		gpiod_warn(desc,
			   "%s: missing set() and direction_output() operations\n",
			   __func__);
		return -EIO;
	}

	if (gc->direction_output) {
		ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val);
	} else {
		/* Check that we are in output mode if we can */
		if (gc->get_direction &&
		    gc->get_direction(gc, gpio_chip_hwgpio(desc))) {
			gpiod_warn(desc,
				"%s: missing direction_output() operation\n",
				__func__);
			return -EIO;
		}
		/*
		 * If we can't actively set the direction, we are some
		 * output-only chip, so just drive the output as desired.
		 */
		gc->set(gc, gpio_chip_hwgpio(desc), val);
	}

	if (!ret)
		set_bit(FLAG_IS_OUT, &desc->flags);
	trace_gpio_value(desc_to_gpio(desc), 0, val);
	trace_gpio_direction(desc_to_gpio(desc), 0, ret);
	return ret;
}

/**
 * gpiod_direction_output_raw - set the GPIO direction to output
 * @desc:	GPIO to set to output
 * @value:	initial output value of the GPIO
 *
 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
 * be called safely on it. The initial value of the output must be specified
 * as raw value on the physical line without regard for the ACTIVE_LOW status.
 *
 * Return 0 in case of success, else an error code.
 */
int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
{
	VALIDATE_DESC(desc);
	return gpiod_direction_output_raw_commit(desc, value);
}
EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);

/**
 * gpiod_direction_output - set the GPIO direction to output
 * @desc:	GPIO to set to output
 * @value:	initial output value of the GPIO
 *
 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can
 * be called safely on it. The initial value of the output must be specified
 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
 * account.
 *
 * Return 0 in case of success, else an error code.
 */
int gpiod_direction_output(struct gpio_desc *desc, int value)
{
	struct gpio_chip *gc;
	int ret;

	VALIDATE_DESC(desc);
	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
		value = !value;
	else
		value = !!value;

	/* GPIOs used for enabled IRQs shall not be set as output */
	if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) &&
	    test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) {
		gpiod_err(desc,
			  "%s: tried to set a GPIO tied to an IRQ as output\n",
			  __func__);
		return -EIO;
	}

	gc = desc->gdev->chip;
	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
		/* First see if we can enable open drain in hardware */
		ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
				      PIN_CONFIG_DRIVE_OPEN_DRAIN);
		if (!ret)
			goto set_output_value;
		/* Emulate open drain by not actively driving the line high */
		if (value) {
			ret = gpiod_direction_input(desc);
			goto set_output_flag;
		}
	}
	else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
		ret = gpio_set_config(gc, gpio_chip_hwgpio(desc),
				      PIN_CONFIG_DRIVE_OPEN_SOURCE);
		if (!ret)
			goto set_output_value;
		/* Emulate open source by not actively driving the line low */
		if (!value) {
			ret = gpiod_direction_input(desc);
			goto set_output_flag;
		}
	} else {
		gpio_set_config(gc, gpio_chip_hwgpio(desc),
				PIN_CONFIG_DRIVE_PUSH_PULL);
	}

set_output_value:
	ret = gpio_set_bias(gc, desc);
	if (ret)
		return ret;
	return gpiod_direction_output_raw_commit(desc, value);

set_output_flag:
	/*
	 * When emulating open-source or open-drain functionalities by not
	 * actively driving the line (setting mode to input) we still need to
	 * set the IS_OUT flag or otherwise we won't be able to set the line
	 * value anymore.
	 */
	if (ret == 0)
		set_bit(FLAG_IS_OUT, &desc->flags);
	return ret;
}
EXPORT_SYMBOL_GPL(gpiod_direction_output);

/**
 * gpiod_set_debounce - sets @debounce time for a GPIO
 * @desc: descriptor of the GPIO for which to set debounce time
 * @debounce: debounce time in microseconds
 *
 * Returns:
 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
 * debounce time.
 */
int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
{
	struct gpio_chip	*chip;
	unsigned long		config;

	VALIDATE_DESC(desc);
	chip = desc->gdev->chip;
	if (!chip->set || !chip->set_config) {
		gpiod_dbg(desc,
			  "%s: missing set() or set_config() operations\n",
			  __func__);
		return -ENOTSUPP;
	}

	config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
	return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
}
EXPORT_SYMBOL_GPL(gpiod_set_debounce);

/**
 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset
 * @desc: descriptor of the GPIO for which to configure persistence
 * @transitory: True to lose state on suspend or reset, false for persistence
 *
 * Returns:
 * 0 on success, otherwise a negative error code.
 */
int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
{
	struct gpio_chip *chip;
	unsigned long packed;
	int gpio;
	int rc;

	VALIDATE_DESC(desc);
	/*
	 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
	 * persistence state.
	 */
	if (transitory)
		set_bit(FLAG_TRANSITORY, &desc->flags);
	else
		clear_bit(FLAG_TRANSITORY, &desc->flags);

	/* If the driver supports it, set the persistence state now */
	chip = desc->gdev->chip;
	if (!chip->set_config)
		return 0;

	packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
					  !transitory);
	gpio = gpio_chip_hwgpio(desc);
	rc = chip->set_config(chip, gpio, packed);
	if (rc == -ENOTSUPP) {
		dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
				gpio);
		return 0;
	}

	return rc;
}
EXPORT_SYMBOL_GPL(gpiod_set_transitory);

/**
 * gpiod_is_active_low - test whether a GPIO is active-low or not
 * @desc: the gpio descriptor to test
 *
 * Returns 1 if the GPIO is active-low, 0 otherwise.
 */
int gpiod_is_active_low(const struct gpio_desc *desc)
{
	VALIDATE_DESC(desc);
	return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
}
EXPORT_SYMBOL_GPL(gpiod_is_active_low);

/* I/O calls are only valid after configuration completed; the relevant
 * "is this a valid GPIO" error checks should already have been done.
 *
 * "Get" operations are often inlinable as reading a pin value register,
 * and masking the relevant bit in that register.
 *
 * When "set" operations are inlinable, they involve writing that mask to
 * one register to set a low value, or a different register to set it high.
 * Otherwise locking is needed, so there may be little value to inlining.
 *
 *------------------------------------------------------------------------
 *
 * IMPORTANT!!!  The hot paths -- get/set value -- assume that callers
 * have requested the GPIO.  That can include implicit requesting by
 * a direction setting call.  Marking a gpio as requested locks its chip
 * in memory, guaranteeing that these table lookups need no more locking
 * and that gpiochip_remove() will fail.
 *
 * REVISIT when debugging, consider adding some instrumentation to ensure
 * that the GPIO was actually requested.
 */

static int gpiod_get_raw_value_commit(const struct gpio_desc *desc)
{
	struct gpio_chip	*chip;
	int offset;
	int value;

	chip = desc->gdev->chip;
	offset = gpio_chip_hwgpio(desc);
	value = chip->get ? chip->get(chip, offset) : -EIO;
	value = value < 0 ? value : !!value;
	trace_gpio_value(desc_to_gpio(desc), 1, value);
	return value;
}

static int gpio_chip_get_multiple(struct gpio_chip *chip,
				  unsigned long *mask, unsigned long *bits)
{
	if (chip->get_multiple) {
		return chip->get_multiple(chip, mask, bits);
	} else if (chip->get) {
		int i, value;

		for_each_set_bit(i, mask, chip->ngpio) {
			value = chip->get(chip, i);
			if (value < 0)
				return value;
			__assign_bit(i, bits, value);
		}
		return 0;
	}
	return -EIO;
}

int gpiod_get_array_value_complex(bool raw, bool can_sleep,
				  unsigned int array_size,
				  struct gpio_desc **desc_array,
				  struct gpio_array *array_info,
				  unsigned long *value_bitmap)
{
	int ret, i = 0;

	/*
	 * Validate array_info against desc_array and its size.
	 * It should immediately follow desc_array if both
	 * have been obtained from the same gpiod_get_array() call.
	 */
	if (array_info && array_info->desc == desc_array &&
	    array_size <= array_info->size &&
	    (void *)array_info == desc_array + array_info->size) {
		if (!can_sleep)
			WARN_ON(array_info->chip->can_sleep);

		ret = gpio_chip_get_multiple(array_info->chip,
					     array_info->get_mask,
					     value_bitmap);
		if (ret)
			return ret;

		if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
			bitmap_xor(value_bitmap, value_bitmap,
				   array_info->invert_mask, array_size);

		if (bitmap_full(array_info->get_mask, array_size))
			return 0;

		i = find_first_zero_bit(array_info->get_mask, array_size);
	} else {
		array_info = NULL;
	}

	while (i < array_size) {
		struct gpio_chip *chip = desc_array[i]->gdev->chip;
		unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
		unsigned long *mask, *bits;
		int first, j, ret;

		if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
			mask = fastpath;
		} else {
			mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
					   sizeof(*mask),
					   can_sleep ? GFP_KERNEL : GFP_ATOMIC);
			if (!mask)
				return -ENOMEM;
		}

		bits = mask + BITS_TO_LONGS(chip->ngpio);
		bitmap_zero(mask, chip->ngpio);

		if (!can_sleep)
			WARN_ON(chip->can_sleep);

		/* collect all inputs belonging to the same chip */
		first = i;
		do {
			const struct gpio_desc *desc = desc_array[i];
			int hwgpio = gpio_chip_hwgpio(desc);

			__set_bit(hwgpio, mask);
			i++;

			if (array_info)
				i = find_next_zero_bit(array_info->get_mask,
						       array_size, i);
		} while ((i < array_size) &&
			 (desc_array[i]->gdev->chip == chip));

		ret = gpio_chip_get_multiple(chip, mask, bits);
		if (ret) {
			if (mask != fastpath)
				kfree(mask);
			return ret;
		}

		for (j = first; j < i; ) {
			const struct gpio_desc *desc = desc_array[j];
			int hwgpio = gpio_chip_hwgpio(desc);
			int value = test_bit(hwgpio, bits);

			if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags))
				value = !value;
			__assign_bit(j, value_bitmap, value);
			trace_gpio_value(desc_to_gpio(desc), 1, value);
			j++;

			if (array_info)
				j = find_next_zero_bit(array_info->get_mask, i,
						       j);
		}

		if (mask != fastpath)
			kfree(mask);
	}
	return 0;
}

/**
 * gpiod_get_raw_value() - return a gpio's raw value
 * @desc: gpio whose value will be returned
 *
 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
 * its ACTIVE_LOW status, or negative errno on failure.
 *
 * This function can be called from contexts where we cannot sleep, and will
 * complain if the GPIO chip functions potentially sleep.
 */
int gpiod_get_raw_value(const struct gpio_desc *desc)
{
	VALIDATE_DESC(desc);
	/* Should be using gpiod_get_raw_value_cansleep() */
	WARN_ON(desc->gdev->chip->can_sleep);
	return gpiod_get_raw_value_commit(desc);
}
EXPORT_SYMBOL_GPL(gpiod_get_raw_value);

/**
 * gpiod_get_value() - return a gpio's value
 * @desc: gpio whose value will be returned
 *
 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
 * account, or negative errno on failure.
 *
 * This function can be called from contexts where we cannot sleep, and will
 * complain if the GPIO chip functions potentially sleep.
 */
int gpiod_get_value(const struct gpio_desc *desc)
{
	int value;

	VALIDATE_DESC(desc);
	/* Should be using gpiod_get_value_cansleep() */
	WARN_ON(desc->gdev->chip->can_sleep);

	value = gpiod_get_raw_value_commit(desc);
	if (value < 0)
		return value;

	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
		value = !value;

	return value;
}
EXPORT_SYMBOL_GPL(gpiod_get_value);

/**
 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be read
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap to store the read values
 *
 * Read the raw values of the GPIOs, i.e. the values of the physical lines
 * without regard for their ACTIVE_LOW status.  Return 0 in case of success,
 * else an error code.
 *
 * This function can be called from contexts where we cannot sleep,
 * and it will complain if the GPIO chip functions potentially sleep.
 */
int gpiod_get_raw_array_value(unsigned int array_size,
			      struct gpio_desc **desc_array,
			      struct gpio_array *array_info,
			      unsigned long *value_bitmap)
{
	if (!desc_array)
		return -EINVAL;
	return gpiod_get_array_value_complex(true, false, array_size,
					     desc_array, array_info,
					     value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value);

/**
 * gpiod_get_array_value() - read values from an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be read
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap to store the read values
 *
 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
 * into account.  Return 0 in case of success, else an error code.
 *
 * This function can be called from contexts where we cannot sleep,
 * and it will complain if the GPIO chip functions potentially sleep.
 */
int gpiod_get_array_value(unsigned int array_size,
			  struct gpio_desc **desc_array,
			  struct gpio_array *array_info,
			  unsigned long *value_bitmap)
{
	if (!desc_array)
		return -EINVAL;
	return gpiod_get_array_value_complex(false, false, array_size,
					     desc_array, array_info,
					     value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_get_array_value);

/*
 *  gpio_set_open_drain_value_commit() - Set the open drain gpio's value.
 * @desc: gpio descriptor whose state need to be set.
 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
 */
static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
{
	int ret = 0;
	struct gpio_chip *chip = desc->gdev->chip;
	int offset = gpio_chip_hwgpio(desc);

	if (value) {
		ret = chip->direction_input(chip, offset);
	} else {
		ret = chip->direction_output(chip, offset, 0);
		if (!ret)
			set_bit(FLAG_IS_OUT, &desc->flags);
	}
	trace_gpio_direction(desc_to_gpio(desc), value, ret);
	if (ret < 0)
		gpiod_err(desc,
			  "%s: Error in set_value for open drain err %d\n",
			  __func__, ret);
}

/*
 *  _gpio_set_open_source_value() - Set the open source gpio's value.
 * @desc: gpio descriptor whose state need to be set.
 * @value: Non-zero for setting it HIGH otherwise it will set to LOW.
 */
static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
{
	int ret = 0;
	struct gpio_chip *chip = desc->gdev->chip;
	int offset = gpio_chip_hwgpio(desc);

	if (value) {
		ret = chip->direction_output(chip, offset, 1);
		if (!ret)
			set_bit(FLAG_IS_OUT, &desc->flags);
	} else {
		ret = chip->direction_input(chip, offset);
	}
	trace_gpio_direction(desc_to_gpio(desc), !value, ret);
	if (ret < 0)
		gpiod_err(desc,
			  "%s: Error in set_value for open source err %d\n",
			  __func__, ret);
}

static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
{
	struct gpio_chip	*chip;

	chip = desc->gdev->chip;
	trace_gpio_value(desc_to_gpio(desc), 0, value);
	chip->set(chip, gpio_chip_hwgpio(desc), value);
}

/*
 * set multiple outputs on the same chip;
 * use the chip's set_multiple function if available;
 * otherwise set the outputs sequentially;
 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
 *        defines which outputs are to be changed
 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
 *        defines the values the outputs specified by mask are to be set to
 */
static void gpio_chip_set_multiple(struct gpio_chip *chip,
				   unsigned long *mask, unsigned long *bits)
{
	if (chip->set_multiple) {
		chip->set_multiple(chip, mask, bits);
	} else {
		unsigned int i;

		/* set outputs if the corresponding mask bit is set */
		for_each_set_bit(i, mask, chip->ngpio)
			chip->set(chip, i, test_bit(i, bits));
	}
}

int gpiod_set_array_value_complex(bool raw, bool can_sleep,
				  unsigned int array_size,
				  struct gpio_desc **desc_array,
				  struct gpio_array *array_info,
				  unsigned long *value_bitmap)
{
	int i = 0;

	/*
	 * Validate array_info against desc_array and its size.
	 * It should immediately follow desc_array if both
	 * have been obtained from the same gpiod_get_array() call.
	 */
	if (array_info && array_info->desc == desc_array &&
	    array_size <= array_info->size &&
	    (void *)array_info == desc_array + array_info->size) {
		if (!can_sleep)
			WARN_ON(array_info->chip->can_sleep);

		if (!raw && !bitmap_empty(array_info->invert_mask, array_size))
			bitmap_xor(value_bitmap, value_bitmap,
				   array_info->invert_mask, array_size);

		gpio_chip_set_multiple(array_info->chip, array_info->set_mask,
				       value_bitmap);

		if (bitmap_full(array_info->set_mask, array_size))
			return 0;

		i = find_first_zero_bit(array_info->set_mask, array_size);
	} else {
		array_info = NULL;
	}

	while (i < array_size) {
		struct gpio_chip *chip = desc_array[i]->gdev->chip;
		unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
		unsigned long *mask, *bits;
		int count = 0;

		if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
			mask = fastpath;
		} else {
			mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
					   sizeof(*mask),
					   can_sleep ? GFP_KERNEL : GFP_ATOMIC);
			if (!mask)
				return -ENOMEM;
		}

		bits = mask + BITS_TO_LONGS(chip->ngpio);
		bitmap_zero(mask, chip->ngpio);

		if (!can_sleep)
			WARN_ON(chip->can_sleep);

		do {
			struct gpio_desc *desc = desc_array[i];
			int hwgpio = gpio_chip_hwgpio(desc);
			int value = test_bit(i, value_bitmap);

			/*
			 * Pins applicable for fast input but not for
			 * fast output processing may have been already
			 * inverted inside the fast path, skip them.
			 */
			if (!raw && !(array_info &&
			    test_bit(i, array_info->invert_mask)) &&
			    test_bit(FLAG_ACTIVE_LOW, &desc->flags))
				value = !value;
			trace_gpio_value(desc_to_gpio(desc), 0, value);
			/*
			 * collect all normal outputs belonging to the same chip
			 * open drain and open source outputs are set individually
			 */
			if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) {
				gpio_set_open_drain_value_commit(desc, value);
			} else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) {
				gpio_set_open_source_value_commit(desc, value);
			} else {
				__set_bit(hwgpio, mask);
				if (value)
					__set_bit(hwgpio, bits);
				else
					__clear_bit(hwgpio, bits);
				count++;
			}
			i++;

			if (array_info)
				i = find_next_zero_bit(array_info->set_mask,
						       array_size, i);
		} while ((i < array_size) &&
			 (desc_array[i]->gdev->chip == chip));
		/* push collected bits to outputs */
		if (count != 0)
			gpio_chip_set_multiple(chip, mask, bits);

		if (mask != fastpath)
			kfree(mask);
	}
	return 0;
}

/**
 * gpiod_set_raw_value() - assign a gpio's raw value
 * @desc: gpio whose value will be assigned
 * @value: value to assign
 *
 * Set the raw value of the GPIO, i.e. the value of its physical line without
 * regard for its ACTIVE_LOW status.
 *
 * This function can be called from contexts where we cannot sleep, and will
 * complain if the GPIO chip functions potentially sleep.
 */
void gpiod_set_raw_value(struct gpio_desc *desc, int value)
{
	VALIDATE_DESC_VOID(desc);
	/* Should be using gpiod_set_raw_value_cansleep() */
	WARN_ON(desc->gdev->chip->can_sleep);
	gpiod_set_raw_value_commit(desc, value);
}
EXPORT_SYMBOL_GPL(gpiod_set_raw_value);

/**
 * gpiod_set_value_nocheck() - set a GPIO line value without checking
 * @desc: the descriptor to set the value on
 * @value: value to set
 *
 * This sets the value of a GPIO line backing a descriptor, applying
 * different semantic quirks like active low and open drain/source
 * handling.
 */
static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value)
{
	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
		value = !value;
	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
		gpio_set_open_drain_value_commit(desc, value);
	else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
		gpio_set_open_source_value_commit(desc, value);
	else
		gpiod_set_raw_value_commit(desc, value);
}

/**
 * gpiod_set_value() - assign a gpio's value
 * @desc: gpio whose value will be assigned
 * @value: value to assign
 *
 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW,
 * OPEN_DRAIN and OPEN_SOURCE flags into account.
 *
 * This function can be called from contexts where we cannot sleep, and will
 * complain if the GPIO chip functions potentially sleep.
 */
void gpiod_set_value(struct gpio_desc *desc, int value)
{
	VALIDATE_DESC_VOID(desc);
	/* Should be using gpiod_set_value_cansleep() */
	WARN_ON(desc->gdev->chip->can_sleep);
	gpiod_set_value_nocheck(desc, value);
}
EXPORT_SYMBOL_GPL(gpiod_set_value);

/**
 * gpiod_set_raw_array_value() - assign values to an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be assigned
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap of values to assign
 *
 * Set the raw values of the GPIOs, i.e. the values of the physical lines
 * without regard for their ACTIVE_LOW status.
 *
 * This function can be called from contexts where we cannot sleep, and will
 * complain if the GPIO chip functions potentially sleep.
 */
int gpiod_set_raw_array_value(unsigned int array_size,
			      struct gpio_desc **desc_array,
			      struct gpio_array *array_info,
			      unsigned long *value_bitmap)
{
	if (!desc_array)
		return -EINVAL;
	return gpiod_set_array_value_complex(true, false, array_size,
					desc_array, array_info, value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);

/**
 * gpiod_set_array_value() - assign values to an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be assigned
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap of values to assign
 *
 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
 * into account.
 *
 * This function can be called from contexts where we cannot sleep, and will
 * complain if the GPIO chip functions potentially sleep.
 */
int gpiod_set_array_value(unsigned int array_size,
			  struct gpio_desc **desc_array,
			  struct gpio_array *array_info,
			  unsigned long *value_bitmap)
{
	if (!desc_array)
		return -EINVAL;
	return gpiod_set_array_value_complex(false, false, array_size,
					     desc_array, array_info,
					     value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_set_array_value);

/**
 * gpiod_cansleep() - report whether gpio value access may sleep
 * @desc: gpio to check
 *
 */
int gpiod_cansleep(const struct gpio_desc *desc)
{
	VALIDATE_DESC(desc);
	return desc->gdev->chip->can_sleep;
}
EXPORT_SYMBOL_GPL(gpiod_cansleep);

/**
 * gpiod_set_consumer_name() - set the consumer name for the descriptor
 * @desc: gpio to set the consumer name on
 * @name: the new consumer name
 */
int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name)
{
	VALIDATE_DESC(desc);
	if (name) {
		name = kstrdup_const(name, GFP_KERNEL);
		if (!name)
			return -ENOMEM;
	}

	kfree_const(desc->label);
	desc_set_label(desc, name);

	return 0;
}
EXPORT_SYMBOL_GPL(gpiod_set_consumer_name);

/**
 * gpiod_to_irq() - return the IRQ corresponding to a GPIO
 * @desc: gpio whose IRQ will be returned (already requested)
 *
 * Return the IRQ corresponding to the passed GPIO, or an error code in case of
 * error.
 */
int gpiod_to_irq(const struct gpio_desc *desc)
{
	struct gpio_chip *chip;
	int offset;

	/*
	 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
	 * requires this function to not return zero on an invalid descriptor
	 * but rather a negative error number.
	 */
	if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
		return -EINVAL;

	chip = desc->gdev->chip;
	offset = gpio_chip_hwgpio(desc);
	if (chip->to_irq) {
		int retirq = chip->to_irq(chip, offset);

		/* Zero means NO_IRQ */
		if (!retirq)
			return -ENXIO;

		return retirq;
	}
	return -ENXIO;
}
EXPORT_SYMBOL_GPL(gpiod_to_irq);

/**
 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ
 * @chip: the chip the GPIO to lock belongs to
 * @offset: the offset of the GPIO to lock as IRQ
 *
 * This is used directly by GPIO drivers that want to lock down
 * a certain GPIO line to be used for IRQs.
 */
int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
{
	struct gpio_desc *desc;

	desc = gpiochip_get_desc(chip, offset);
	if (IS_ERR(desc))
		return PTR_ERR(desc);

	/*
	 * If it's fast: flush the direction setting if something changed
	 * behind our back
	 */
	if (!chip->can_sleep && chip->get_direction) {
		int dir = gpiod_get_direction(desc);

		if (dir < 0) {
			chip_err(chip, "%s: cannot get GPIO direction\n",
				 __func__);
			return dir;
		}
	}

	if (test_bit(FLAG_IS_OUT, &desc->flags)) {
		chip_err(chip,
			 "%s: tried to flag a GPIO set as output for IRQ\n",
			 __func__);
		return -EIO;
	}

	set_bit(FLAG_USED_AS_IRQ, &desc->flags);
	set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);

	/*
	 * If the consumer has not set up a label (such as when the
	 * IRQ is referenced from .to_irq()) we set up a label here
	 * so it is clear this is used as an interrupt.
	 */
	if (!desc->label)
		desc_set_label(desc, "interrupt");

	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);

/**
 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ
 * @chip: the chip the GPIO to lock belongs to
 * @offset: the offset of the GPIO to lock as IRQ
 *
 * This is used directly by GPIO drivers that want to indicate
 * that a certain GPIO is no longer used exclusively for IRQ.
 */
void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset)
{
	struct gpio_desc *desc;

	desc = gpiochip_get_desc(chip, offset);
	if (IS_ERR(desc))
		return;

	clear_bit(FLAG_USED_AS_IRQ, &desc->flags);
	clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);

	/* If we only had this marking, erase it */
	if (desc->label && !strcmp(desc->label, "interrupt"))
		desc_set_label(desc, NULL);
}
EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);

void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset)
{
	struct gpio_desc *desc = gpiochip_get_desc(chip, offset);

	if (!IS_ERR(desc) &&
	    !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags)))
		clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
}
EXPORT_SYMBOL_GPL(gpiochip_disable_irq);

void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset)
{
	struct gpio_desc *desc = gpiochip_get_desc(chip, offset);

	if (!IS_ERR(desc) &&
	    !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
		WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags));
		set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
	}
}
EXPORT_SYMBOL_GPL(gpiochip_enable_irq);

bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset)
{
	if (offset >= chip->ngpio)
		return false;

	return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
}
EXPORT_SYMBOL_GPL(gpiochip_line_is_irq);

int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset)
{
	int ret;

	if (!try_module_get(chip->gpiodev->owner))
		return -ENODEV;

	ret = gpiochip_lock_as_irq(chip, offset);
	if (ret) {
		chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset);
		module_put(chip->gpiodev->owner);
		return ret;
	}
	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_reqres_irq);

void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset)
{
	gpiochip_unlock_as_irq(chip, offset);
	module_put(chip->gpiodev->owner);
}
EXPORT_SYMBOL_GPL(gpiochip_relres_irq);

bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset)
{
	if (offset >= chip->ngpio)
		return false;

	return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags);
}
EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain);

bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset)
{
	if (offset >= chip->ngpio)
		return false;

	return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags);
}
EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source);

bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset)
{
	if (offset >= chip->ngpio)
		return false;

	return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags);
}
EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent);

/**
 * gpiod_get_raw_value_cansleep() - return a gpio's raw value
 * @desc: gpio whose value will be returned
 *
 * Return the GPIO's raw value, i.e. the value of the physical line disregarding
 * its ACTIVE_LOW status, or negative errno on failure.
 *
 * This function is to be called from contexts that can sleep.
 */
int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
{
	might_sleep_if(extra_checks);
	VALIDATE_DESC(desc);
	return gpiod_get_raw_value_commit(desc);
}
EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);

/**
 * gpiod_get_value_cansleep() - return a gpio's value
 * @desc: gpio whose value will be returned
 *
 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
 * account, or negative errno on failure.
 *
 * This function is to be called from contexts that can sleep.
 */
int gpiod_get_value_cansleep(const struct gpio_desc *desc)
{
	int value;

	might_sleep_if(extra_checks);
	VALIDATE_DESC(desc);
	value = gpiod_get_raw_value_commit(desc);
	if (value < 0)
		return value;

	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
		value = !value;

	return value;
}
EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);

/**
 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be read
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap to store the read values
 *
 * Read the raw values of the GPIOs, i.e. the values of the physical lines
 * without regard for their ACTIVE_LOW status.  Return 0 in case of success,
 * else an error code.
 *
 * This function is to be called from contexts that can sleep.
 */
int gpiod_get_raw_array_value_cansleep(unsigned int array_size,
				       struct gpio_desc **desc_array,
				       struct gpio_array *array_info,
				       unsigned long *value_bitmap)
{
	might_sleep_if(extra_checks);
	if (!desc_array)
		return -EINVAL;
	return gpiod_get_array_value_complex(true, true, array_size,
					     desc_array, array_info,
					     value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep);

/**
 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be read
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap to store the read values
 *
 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
 * into account.  Return 0 in case of success, else an error code.
 *
 * This function is to be called from contexts that can sleep.
 */
int gpiod_get_array_value_cansleep(unsigned int array_size,
				   struct gpio_desc **desc_array,
				   struct gpio_array *array_info,
				   unsigned long *value_bitmap)
{
	might_sleep_if(extra_checks);
	if (!desc_array)
		return -EINVAL;
	return gpiod_get_array_value_complex(false, true, array_size,
					     desc_array, array_info,
					     value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep);

/**
 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value
 * @desc: gpio whose value will be assigned
 * @value: value to assign
 *
 * Set the raw value of the GPIO, i.e. the value of its physical line without
 * regard for its ACTIVE_LOW status.
 *
 * This function is to be called from contexts that can sleep.
 */
void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
{
	might_sleep_if(extra_checks);
	VALIDATE_DESC_VOID(desc);
	gpiod_set_raw_value_commit(desc, value);
}
EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);

/**
 * gpiod_set_value_cansleep() - assign a gpio's value
 * @desc: gpio whose value will be assigned
 * @value: value to assign
 *
 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into
 * account
 *
 * This function is to be called from contexts that can sleep.
 */
void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
{
	might_sleep_if(extra_checks);
	VALIDATE_DESC_VOID(desc);
	gpiod_set_value_nocheck(desc, value);
}
EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);

/**
 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be assigned
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap of values to assign
 *
 * Set the raw values of the GPIOs, i.e. the values of the physical lines
 * without regard for their ACTIVE_LOW status.
 *
 * This function is to be called from contexts that can sleep.
 */
int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
				       struct gpio_desc **desc_array,
				       struct gpio_array *array_info,
				       unsigned long *value_bitmap)
{
	might_sleep_if(extra_checks);
	if (!desc_array)
		return -EINVAL;
	return gpiod_set_array_value_complex(true, true, array_size, desc_array,
				      array_info, value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);

/**
 * gpiod_add_lookup_tables() - register GPIO device consumers
 * @tables: list of tables of consumers to register
 * @n: number of tables in the list
 */
void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n)
{
	unsigned int i;

	mutex_lock(&gpio_lookup_lock);

	for (i = 0; i < n; i++)
		list_add_tail(&tables[i]->list, &gpio_lookup_list);

	mutex_unlock(&gpio_lookup_lock);
}

/**
 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs
 * @array_size: number of elements in the descriptor array / value bitmap
 * @desc_array: array of GPIO descriptors whose values will be assigned
 * @array_info: information on applicability of fast bitmap processing path
 * @value_bitmap: bitmap of values to assign
 *
 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status
 * into account.
 *
 * This function is to be called from contexts that can sleep.
 */
int gpiod_set_array_value_cansleep(unsigned int array_size,
				   struct gpio_desc **desc_array,
				   struct gpio_array *array_info,
				   unsigned long *value_bitmap)
{
	might_sleep_if(extra_checks);
	if (!desc_array)
		return -EINVAL;
	return gpiod_set_array_value_complex(false, true, array_size,
					     desc_array, array_info,
					     value_bitmap);
}
EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep);

/**
 * gpiod_add_lookup_table() - register GPIO device consumers
 * @table: table of consumers to register
 */
void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
{
	mutex_lock(&gpio_lookup_lock);

	list_add_tail(&table->list, &gpio_lookup_list);

	mutex_unlock(&gpio_lookup_lock);
}
EXPORT_SYMBOL_GPL(gpiod_add_lookup_table);

/**
 * gpiod_remove_lookup_table() - unregister GPIO device consumers
 * @table: table of consumers to unregister
 */
void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
{
	mutex_lock(&gpio_lookup_lock);

	list_del(&table->list);

	mutex_unlock(&gpio_lookup_lock);
}
EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);

/**
 * gpiod_add_hogs() - register a set of GPIO hogs from machine code
 * @hogs: table of gpio hog entries with a zeroed sentinel at the end
 */
void gpiod_add_hogs(struct gpiod_hog *hogs)
{
	struct gpio_chip *chip;
	struct gpiod_hog *hog;

	mutex_lock(&gpio_machine_hogs_mutex);

	for (hog = &hogs[0]; hog->chip_label; hog++) {
		list_add_tail(&hog->list, &gpio_machine_hogs);

		/*
		 * The chip may have been registered earlier, so check if it
		 * exists and, if so, try to hog the line now.
		 */
		chip = find_chip_by_name(hog->chip_label);
		if (chip)
			gpiochip_machine_hog(chip, hog);
	}

	mutex_unlock(&gpio_machine_hogs_mutex);
}
EXPORT_SYMBOL_GPL(gpiod_add_hogs);

static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
{
	const char *dev_id = dev ? dev_name(dev) : NULL;
	struct gpiod_lookup_table *table;

	mutex_lock(&gpio_lookup_lock);

	list_for_each_entry(table, &gpio_lookup_list, list) {
		if (table->dev_id && dev_id) {
			/*
			 * Valid strings on both ends, must be identical to have
			 * a match
			 */
			if (!strcmp(table->dev_id, dev_id))
				goto found;
		} else {
			/*
			 * One of the pointers is NULL, so both must be to have
			 * a match
			 */
			if (dev_id == table->dev_id)
				goto found;
		}
	}
	table = NULL;

found:
	mutex_unlock(&gpio_lookup_lock);
	return table;
}

static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
				    unsigned int idx, unsigned long *flags)
{
	struct gpio_desc *desc = ERR_PTR(-ENOENT);
	struct gpiod_lookup_table *table;
	struct gpiod_lookup *p;

	table = gpiod_find_lookup_table(dev);
	if (!table)
		return desc;

	for (p = &table->table[0]; p->chip_label; p++) {
		struct gpio_chip *chip;

		/* idx must always match exactly */
		if (p->idx != idx)
			continue;

		/* If the lookup entry has a con_id, require exact match */
		if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
			continue;

		chip = find_chip_by_name(p->chip_label);

		if (!chip) {
			/*
			 * As the lookup table indicates a chip with
			 * p->chip_label should exist, assume it may
			 * still appear later and let the interested
			 * consumer be probed again or let the Deferred
			 * Probe infrastructure handle the error.
			 */
			dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
				 p->chip_label);
			return ERR_PTR(-EPROBE_DEFER);
		}

		if (chip->ngpio <= p->chip_hwnum) {
			dev_err(dev,
				"requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
				idx, p->chip_hwnum, chip->ngpio - 1,
				chip->label);
			return ERR_PTR(-EINVAL);
		}

		desc = gpiochip_get_desc(chip, p->chip_hwnum);
		*flags = p->flags;

		return desc;
	}

	return desc;
}

static int platform_gpio_count(struct device *dev, const char *con_id)
{
	struct gpiod_lookup_table *table;
	struct gpiod_lookup *p;
	unsigned int count = 0;

	table = gpiod_find_lookup_table(dev);
	if (!table)
		return -ENOENT;

	for (p = &table->table[0]; p->chip_label; p++) {
		if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
		    (!con_id && !p->con_id))
			count++;
	}
	if (!count)
		return -ENOENT;

	return count;
}

/**
 * fwnode_gpiod_get_index - obtain a GPIO from firmware node
 * @fwnode:	handle of the firmware node
 * @con_id:	function within the GPIO consumer
 * @index:	index of the GPIO to obtain for the consumer
 * @flags:	GPIO initialization flags
 * @label:	label to attach to the requested GPIO
 *
 * This function can be used for drivers that get their configuration
 * from opaque firmware.
 *
 * The function properly finds the corresponding GPIO using whatever is the
 * underlying firmware interface and then makes sure that the GPIO
 * descriptor is requested before it is returned to the caller.
 *
 * Returns:
 * On successful request the GPIO pin is configured in accordance with
 * provided @flags.
 *
 * In case of error an ERR_PTR() is returned.
 */
struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode,
					 const char *con_id, int index,
					 enum gpiod_flags flags,
					 const char *label)
{
	struct gpio_desc *desc;
	char prop_name[32]; /* 32 is max size of property name */
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
		if (con_id)
			snprintf(prop_name, sizeof(prop_name), "%s-%s",
					    con_id, gpio_suffixes[i]);
		else
			snprintf(prop_name, sizeof(prop_name), "%s",
					    gpio_suffixes[i]);

		desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags,
					      label);
		if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
			break;
	}

	return desc;
}
EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index);

/**
 * gpiod_count - return the number of GPIOs associated with a device / function
 *		or -ENOENT if no GPIO has been assigned to the requested function
 * @dev:	GPIO consumer, can be NULL for system-global GPIOs
 * @con_id:	function within the GPIO consumer
 */
int gpiod_count(struct device *dev, const char *con_id)
{
	int count = -ENOENT;

	if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
		count = of_gpio_get_count(dev, con_id);
	else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
		count = acpi_gpio_count(dev, con_id);

	if (count < 0)
		count = platform_gpio_count(dev, con_id);

	return count;
}
EXPORT_SYMBOL_GPL(gpiod_count);

/**
 * gpiod_get - obtain a GPIO for a given GPIO function
 * @dev:	GPIO consumer, can be NULL for system-global GPIOs
 * @con_id:	function within the GPIO consumer
 * @flags:	optional GPIO initialization flags
 *
 * Return the GPIO descriptor corresponding to the function con_id of device
 * dev, -ENOENT if no GPIO has been assigned to the requested function, or
 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
 */
struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
					 enum gpiod_flags flags)
{
	return gpiod_get_index(dev, con_id, 0, flags);
}
EXPORT_SYMBOL_GPL(gpiod_get);

/**
 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function
 * @dev: GPIO consumer, can be NULL for system-global GPIOs
 * @con_id: function within the GPIO consumer
 * @flags: optional GPIO initialization flags
 *
 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to
 * the requested function it will return NULL. This is convenient for drivers
 * that need to handle optional GPIOs.
 */
struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
						  const char *con_id,
						  enum gpiod_flags flags)
{
	return gpiod_get_index_optional(dev, con_id, 0, flags);
}
EXPORT_SYMBOL_GPL(gpiod_get_optional);


/**
 * gpiod_configure_flags - helper function to configure a given GPIO
 * @desc:	gpio whose value will be assigned
 * @con_id:	function within the GPIO consumer
 * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
 *		of_find_gpio() or of_get_gpio_hog()
 * @dflags:	gpiod_flags - optional GPIO initialization flags
 *
 * Return 0 on success, -ENOENT if no GPIO has been assigned to the
 * requested function and/or index, or another IS_ERR() code if an error
 * occurred while trying to acquire the GPIO.
 */
int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
		unsigned long lflags, enum gpiod_flags dflags)
{
	int ret;

	if (lflags & GPIO_ACTIVE_LOW)
		set_bit(FLAG_ACTIVE_LOW, &desc->flags);

	if (lflags & GPIO_OPEN_DRAIN)
		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
	else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) {
		/*
		 * This enforces open drain mode from the consumer side.
		 * This is necessary for some busses like I2C, but the lookup
		 * should *REALLY* have specified them as open drain in the
		 * first place, so print a little warning here.
		 */
		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
		gpiod_warn(desc,
			   "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n");
	}

	if (lflags & GPIO_OPEN_SOURCE)
		set_bit(FLAG_OPEN_SOURCE, &desc->flags);

	if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) {
		gpiod_err(desc,
			  "both pull-up and pull-down enabled, invalid configuration\n");
		return -EINVAL;
	}

	if (lflags & GPIO_PULL_UP)
		set_bit(FLAG_PULL_UP, &desc->flags);
	else if (lflags & GPIO_PULL_DOWN)
		set_bit(FLAG_PULL_DOWN, &desc->flags);

	ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY));
	if (ret < 0)
		return ret;

	/* No particular flag request, return here... */
	if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
		pr_debug("no flags found for %s\n", con_id);
		return 0;
	}

	/* Process flags */
	if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
		ret = gpiod_direction_output(desc,
				!!(dflags & GPIOD_FLAGS_BIT_DIR_VAL));
	else
		ret = gpiod_direction_input(desc);

	return ret;
}

/**
 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
 * @dev:	GPIO consumer, can be NULL for system-global GPIOs
 * @con_id:	function within the GPIO consumer
 * @idx:	index of the GPIO to obtain in the consumer
 * @flags:	optional GPIO initialization flags
 *
 * This variant of gpiod_get() allows to access GPIOs other than the first
 * defined one for functions that define several GPIOs.
 *
 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the
 * requested function and/or index, or another IS_ERR() code if an error
 * occurred while trying to acquire the GPIO.
 */
struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
					       const char *con_id,
					       unsigned int idx,
					       enum gpiod_flags flags)
{
	unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT;
	struct gpio_desc *desc = NULL;
	int ret;
	/* Maybe we have a device name, maybe not */
	const char *devname = dev ? dev_name(dev) : "?";

	dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);

	if (dev) {
		/* Using device tree? */
		if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
			dev_dbg(dev, "using device tree for GPIO lookup\n");
			desc = of_find_gpio(dev, con_id, idx, &lookupflags);
		} else if (ACPI_COMPANION(dev)) {
			dev_dbg(dev, "using ACPI for GPIO lookup\n");
			desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags);
		}
	}

	/*
	 * Either we are not using DT or ACPI, or their lookup did not return
	 * a result. In that case, use platform lookup as a fallback.
	 */
	if (!desc || desc == ERR_PTR(-ENOENT)) {
		dev_dbg(dev, "using lookup tables for GPIO lookup\n");
		desc = gpiod_find(dev, con_id, idx, &lookupflags);
	}

	if (IS_ERR(desc)) {
		dev_dbg(dev, "No GPIO consumer %s found\n", con_id);
		return desc;
	}

	/*
	 * If a connection label was passed use that, else attempt to use
	 * the device name as label
	 */
	ret = gpiod_request(desc, con_id ? con_id : devname);
	if (ret < 0) {
		if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
			/*
			 * This happens when there are several consumers for
			 * the same GPIO line: we just return here without
			 * further initialization. It is a bit if a hack.
			 * This is necessary to support fixed regulators.
			 *
			 * FIXME: Make this more sane and safe.
			 */
			dev_info(dev, "nonexclusive access to GPIO for %s\n",
				 con_id ? con_id : devname);
			return desc;
		} else {
			return ERR_PTR(ret);
		}
	}

	ret = gpiod_configure_flags(desc, con_id, lookupflags, flags);
	if (ret < 0) {
		dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
		gpiod_put(desc);
		return ERR_PTR(ret);
	}

	return desc;
}
EXPORT_SYMBOL_GPL(gpiod_get_index);

/**
 * fwnode_get_named_gpiod - obtain a GPIO from firmware node
 * @fwnode:	handle of the firmware node
 * @propname:	name of the firmware property representing the GPIO
 * @index:	index of the GPIO to obtain for the consumer
 * @dflags:	GPIO initialization flags
 * @label:	label to attach to the requested GPIO
 *
 * This function can be used for drivers that get their configuration
 * from opaque firmware.
 *
 * The function properly finds the corresponding GPIO using whatever is the
 * underlying firmware interface and then makes sure that the GPIO
 * descriptor is requested before it is returned to the caller.
 *
 * Returns:
 * On successful request the GPIO pin is configured in accordance with
 * provided @dflags.
 *
 * In case of error an ERR_PTR() is returned.
 */
struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
					 const char *propname, int index,
					 enum gpiod_flags dflags,
					 const char *label)
{
	unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
	struct gpio_desc *desc = ERR_PTR(-ENODEV);
	int ret;

	if (!fwnode)
		return ERR_PTR(-EINVAL);

	if (is_of_node(fwnode)) {
		desc = gpiod_get_from_of_node(to_of_node(fwnode),
					      propname, index,
					      dflags,
					      label);
		return desc;
	} else if (is_acpi_node(fwnode)) {
		struct acpi_gpio_info info;

		desc = acpi_node_get_gpiod(fwnode, propname, index, &info);
		if (IS_ERR(desc))
			return desc;

		acpi_gpio_update_gpiod_flags(&dflags, &info);
		acpi_gpio_update_gpiod_lookup_flags(&lflags, &info);
	}

	/* Currently only ACPI takes this path */
	ret = gpiod_request(desc, label);
	if (ret)
		return ERR_PTR(ret);

	ret = gpiod_configure_flags(desc, propname, lflags, dflags);
	if (ret < 0) {
		gpiod_put(desc);
		return ERR_PTR(ret);
	}

	return desc;
}
EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);

/**
 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO
 *                            function
 * @dev: GPIO consumer, can be NULL for system-global GPIOs
 * @con_id: function within the GPIO consumer
 * @index: index of the GPIO to obtain in the consumer
 * @flags: optional GPIO initialization flags
 *
 * This is equivalent to gpiod_get_index(), except that when no GPIO with the
 * specified index was assigned to the requested function it will return NULL.
 * This is convenient for drivers that need to handle optional GPIOs.
 */
struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
							const char *con_id,
							unsigned int index,
							enum gpiod_flags flags)
{
	struct gpio_desc *desc;

	desc = gpiod_get_index(dev, con_id, index, flags);
	if (IS_ERR(desc)) {
		if (PTR_ERR(desc) == -ENOENT)
			return NULL;
	}

	return desc;
}
EXPORT_SYMBOL_GPL(gpiod_get_index_optional);

/**
 * gpiod_hog - Hog the specified GPIO desc given the provided flags
 * @desc:	gpio whose value will be assigned
 * @name:	gpio line name
 * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
 *		of_find_gpio() or of_get_gpio_hog()
 * @dflags:	gpiod_flags - optional GPIO initialization flags
 */
int gpiod_hog(struct gpio_desc *desc, const char *name,
	      unsigned long lflags, enum gpiod_flags dflags)
{
	struct gpio_chip *chip;
	struct gpio_desc *local_desc;
	int hwnum;
	int ret;

	chip = gpiod_to_chip(desc);
	hwnum = gpio_chip_hwgpio(desc);

	local_desc = gpiochip_request_own_desc(chip, hwnum, name,
					       lflags, dflags);
	if (IS_ERR(local_desc)) {
		ret = PTR_ERR(local_desc);
		pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
		       name, chip->label, hwnum, ret);
		return ret;
	}

	/* Mark GPIO as hogged so it can be identified and removed later */
	set_bit(FLAG_IS_HOGGED, &desc->flags);

	pr_info("GPIO line %d (%s) hogged as %s%s\n",
		desc_to_gpio(desc), name,
		(dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
		(dflags & GPIOD_FLAGS_BIT_DIR_OUT) ?
		  (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : "");

	return 0;
}

/**
 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
 * @chip:	gpio chip to act on
 */
static void gpiochip_free_hogs(struct gpio_chip *chip)
{
	int id;

	for (id = 0; id < chip->ngpio; id++) {
		if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags))
			gpiochip_free_own_desc(&chip->gpiodev->descs[id]);
	}
}

/**
 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
 * @dev:	GPIO consumer, can be NULL for system-global GPIOs
 * @con_id:	function within the GPIO consumer
 * @flags:	optional GPIO initialization flags
 *
 * This function acquires all the GPIOs defined under a given function.
 *
 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
 * no GPIO has been assigned to the requested function, or another IS_ERR()
 * code if an error occurred while trying to acquire the GPIOs.
 */
struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
						const char *con_id,
						enum gpiod_flags flags)
{
	struct gpio_desc *desc;
	struct gpio_descs *descs;
	struct gpio_array *array_info = NULL;
	struct gpio_chip *chip;
	int count, bitmap_size;

	count = gpiod_count(dev, con_id);
	if (count < 0)
		return ERR_PTR(count);

	descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
	if (!descs)
		return ERR_PTR(-ENOMEM);

	for (descs->ndescs = 0; descs->ndescs < count; ) {
		desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
		if (IS_ERR(desc)) {
			gpiod_put_array(descs);
			return ERR_CAST(desc);
		}

		descs->desc[descs->ndescs] = desc;

		chip = gpiod_to_chip(desc);
		/*
		 * If pin hardware number of array member 0 is also 0, select
		 * its chip as a candidate for fast bitmap processing path.
		 */
		if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) {
			struct gpio_descs *array;

			bitmap_size = BITS_TO_LONGS(chip->ngpio > count ?
						    chip->ngpio : count);

			array = kzalloc(struct_size(descs, desc, count) +
					struct_size(array_info, invert_mask,
					3 * bitmap_size), GFP_KERNEL);
			if (!array) {
				gpiod_put_array(descs);
				return ERR_PTR(-ENOMEM);
			}

			memcpy(array, descs,
			       struct_size(descs, desc, descs->ndescs + 1));
			kfree(descs);

			descs = array;
			array_info = (void *)(descs->desc + count);
			array_info->get_mask = array_info->invert_mask +
						  bitmap_size;
			array_info->set_mask = array_info->get_mask +
						  bitmap_size;

			array_info->desc = descs->desc;
			array_info->size = count;
			array_info->chip = chip;
			bitmap_set(array_info->get_mask, descs->ndescs,
				   count - descs->ndescs);
			bitmap_set(array_info->set_mask, descs->ndescs,
				   count - descs->ndescs);
			descs->info = array_info;
		}
		/* Unmark array members which don't belong to the 'fast' chip */
		if (array_info && array_info->chip != chip) {
			__clear_bit(descs->ndescs, array_info->get_mask);
			__clear_bit(descs->ndescs, array_info->set_mask);
		}
		/*
		 * Detect array members which belong to the 'fast' chip
		 * but their pins are not in hardware order.
		 */
		else if (array_info &&
			   gpio_chip_hwgpio(desc) != descs->ndescs) {
			/*
			 * Don't use fast path if all array members processed so
			 * far belong to the same chip as this one but its pin
			 * hardware number is different from its array index.
			 */
			if (bitmap_full(array_info->get_mask, descs->ndescs)) {
				array_info = NULL;
			} else {
				__clear_bit(descs->ndescs,
					    array_info->get_mask);
				__clear_bit(descs->ndescs,
					    array_info->set_mask);
			}
		} else if (array_info) {
			/* Exclude open drain or open source from fast output */
			if (gpiochip_line_is_open_drain(chip, descs->ndescs) ||
			    gpiochip_line_is_open_source(chip, descs->ndescs))
				__clear_bit(descs->ndescs,
					    array_info->set_mask);
			/* Identify 'fast' pins which require invertion */
			if (gpiod_is_active_low(desc))
				__set_bit(descs->ndescs,
					  array_info->invert_mask);
		}

		descs->ndescs++;
	}
	if (array_info)
		dev_dbg(dev,
			"GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n",
			array_info->chip->label, array_info->size,
			*array_info->get_mask, *array_info->set_mask,
			*array_info->invert_mask);
	return descs;
}
EXPORT_SYMBOL_GPL(gpiod_get_array);

/**
 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
 *                            function
 * @dev:	GPIO consumer, can be NULL for system-global GPIOs
 * @con_id:	function within the GPIO consumer
 * @flags:	optional GPIO initialization flags
 *
 * This is equivalent to gpiod_get_array(), except that when no GPIO was
 * assigned to the requested function it will return NULL.
 */
struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
							const char *con_id,
							enum gpiod_flags flags)
{
	struct gpio_descs *descs;

	descs = gpiod_get_array(dev, con_id, flags);
	if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
		return NULL;

	return descs;
}
EXPORT_SYMBOL_GPL(gpiod_get_array_optional);

/**
 * gpiod_put - dispose of a GPIO descriptor
 * @desc:	GPIO descriptor to dispose of
 *
 * No descriptor can be used after gpiod_put() has been called on it.
 */
void gpiod_put(struct gpio_desc *desc)
{
	if (desc)
		gpiod_free(desc);
}
EXPORT_SYMBOL_GPL(gpiod_put);

/**
 * gpiod_put_array - dispose of multiple GPIO descriptors
 * @descs:	struct gpio_descs containing an array of descriptors
 */
void gpiod_put_array(struct gpio_descs *descs)
{
	unsigned int i;

	for (i = 0; i < descs->ndescs; i++)
		gpiod_put(descs->desc[i]);

	kfree(descs);
}
EXPORT_SYMBOL_GPL(gpiod_put_array);

static int __init gpiolib_dev_init(void)
{
	int ret;

	/* Register GPIO sysfs bus */
	ret = bus_register(&gpio_bus_type);
	if (ret < 0) {
		pr_err("gpiolib: could not register GPIO bus type\n");
		return ret;
	}

	ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip");
	if (ret < 0) {
		pr_err("gpiolib: failed to allocate char dev region\n");
		bus_unregister(&gpio_bus_type);
	} else {
		gpiolib_initialized = true;
		gpiochip_setup_devs();
	}
	return ret;
}
core_initcall(gpiolib_dev_init);

#ifdef CONFIG_DEBUG_FS

static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
{
	unsigned		i;
	struct gpio_chip	*chip = gdev->chip;
	unsigned		gpio = gdev->base;
	struct gpio_desc	*gdesc = &gdev->descs[0];
	bool			is_out;
	bool			is_irq;
	bool			active_low;

	for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
		if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
			if (gdesc->name) {
				seq_printf(s, " gpio-%-3d (%-20.20s)\n",
					   gpio, gdesc->name);
			}
			continue;
		}

		gpiod_get_direction(gdesc);
		is_out = test_bit(FLAG_IS_OUT, &gdesc->flags);
		is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags);
		active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags);
		seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s",
			gpio, gdesc->name ? gdesc->name : "", gdesc->label,
			is_out ? "out" : "in ",
			chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "?  ",
			is_irq ? "IRQ " : "",
			active_low ? "ACTIVE LOW" : "");
		seq_printf(s, "\n");
	}
}

static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos)
{
	unsigned long flags;
	struct gpio_device *gdev = NULL;
	loff_t index = *pos;

	s->private = "";

	spin_lock_irqsave(&gpio_lock, flags);
	list_for_each_entry(gdev, &gpio_devices, list)
		if (index-- == 0) {
			spin_unlock_irqrestore(&gpio_lock, flags);
			return gdev;
		}
	spin_unlock_irqrestore(&gpio_lock, flags);

	return NULL;
}

static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
	unsigned long flags;
	struct gpio_device *gdev = v;
	void *ret = NULL;

	spin_lock_irqsave(&gpio_lock, flags);
	if (list_is_last(&gdev->list, &gpio_devices))
		ret = NULL;
	else
		ret = list_entry(gdev->list.next, struct gpio_device, list);
	spin_unlock_irqrestore(&gpio_lock, flags);

	s->private = "\n";
	++*pos;

	return ret;
}

static void gpiolib_seq_stop(struct seq_file *s, void *v)
{
}

static int gpiolib_seq_show(struct seq_file *s, void *v)
{
	struct gpio_device *gdev = v;
	struct gpio_chip *chip = gdev->chip;
	struct device *parent;

	if (!chip) {
		seq_printf(s, "%s%s: (dangling chip)", (char *)s->private,
			   dev_name(&gdev->dev));
		return 0;
	}

	seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
		   dev_name(&gdev->dev),
		   gdev->base, gdev->base + gdev->ngpio - 1);
	parent = chip->parent;
	if (parent)
		seq_printf(s, ", parent: %s/%s",
			   parent->bus ? parent->bus->name : "no-bus",
			   dev_name(parent));
	if (chip->label)
		seq_printf(s, ", %s", chip->label);
	if (chip->can_sleep)
		seq_printf(s, ", can sleep");
	seq_printf(s, ":\n");

	if (chip->dbg_show)
		chip->dbg_show(s, chip);
	else
		gpiolib_dbg_show(s, gdev);

	return 0;
}

static const struct seq_operations gpiolib_seq_ops = {
	.start = gpiolib_seq_start,
	.next = gpiolib_seq_next,
	.stop = gpiolib_seq_stop,
	.show = gpiolib_seq_show,
};

static int gpiolib_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &gpiolib_seq_ops);
}

static const struct file_operations gpiolib_operations = {
	.owner		= THIS_MODULE,
	.open		= gpiolib_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

static int __init gpiolib_debugfs_init(void)
{
	/* /sys/kernel/debug/gpio */
	debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
			    &gpiolib_operations);
	return 0;
}
subsys_initcall(gpiolib_debugfs_init);

#endif	/* DEBUG_FS */