gpiolib.c 121 KB
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
// 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/fs.h>
#include <linux/compat.h>
#include <linux/file.h>
#include <uapi/linux/gpio.h>

#include "gpiolib.h"
#include "gpiolib-of.h"
#include "gpiolib-acpi.h"
#include "gpiolib-cdev.h"
#include "gpiolib-sysfs.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 *gc);
static int gpiochip_add_irqchip(struct gpio_chip *gc,
				struct lock_class_key *lock_key,
				struct lock_class_key *request_key);
static void gpiochip_irqchip_remove(struct gpio_chip *gc);
static int gpiochip_irqchip_init_hw(struct gpio_chip *gc);
static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc);
static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc);

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
 * @gc: 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 *gc,
				    unsigned int hwnum)
{
	struct gpio_device *gdev = gc->gpiodev;

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

	return &gdev->descs[hwnum];
}
EXPORT_SYMBOL_GPL(gpiochip_get_desc);

/**
 * 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 *gc;
	unsigned offset;
	int ret;

	gc = 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 (!gc->get_direction)
		return -ENOTSUPP;

	ret = gc->get_direction(gc, offset);
	if (ret < 0)
		return ret;

	/* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */
	if (ret > 0)
		ret = 1;

	assign_bit(FLAG_IS_OUT, &desc->flags, !ret);

	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
 * Note that there is no guarantee that GPIO names are globally unique!
 * Hence this function will return, if it exists, a reference to the first GPIO
 * line found that matches the given name.
 */
static struct gpio_desc *gpio_name_to_desc(const char * const name)
{
	struct gpio_device *gdev;
	unsigned long flags;

	if (!name)
		return NULL;

	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)
				continue;

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

	spin_unlock_irqrestore(&gpio_lock, flags);

	return NULL;
}

/*
 * Take the names from gc->names and assign them to their GPIO descriptors.
 * Warn if a name is already used for a GPIO line on a different GPIO chip.
 *
 * Note that:
 *   1. Non-unique names are still accepted,
 *   2. Name collisions within the same GPIO chip are not reported.
 */
static int gpiochip_set_desc_names(struct gpio_chip *gc)
{
	struct gpio_device *gdev = gc->gpiodev;
	int i;

	/* 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;
}

/*
 * devprop_gpiochip_set_names - Set GPIO line names using device properties
 * @chip: GPIO chip whose lines should be named, if possible
 *
 * Looks for device property "gpio-line-names" and if it exists assigns
 * GPIO line names for the chip. The memory allocated for the assigned
 * names belong to the underlying software node and should not be released
 * by the caller.
 */
static int devprop_gpiochip_set_names(struct gpio_chip *chip)
{
	struct gpio_device *gdev = chip->gpiodev;
	struct device *dev = chip->parent;
	const char **names;
	int ret, i;
	int count;

	/* GPIO chip may not have a parent device whose properties we inspect. */
	if (!dev)
		return 0;

	count = device_property_string_array_count(dev, "gpio-line-names");
	if (count < 0)
		return 0;

	if (count > gdev->ngpio) {
		dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
			 count, gdev->ngpio);
		count = gdev->ngpio;
	}

	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
	if (!names)
		return -ENOMEM;

	ret = device_property_read_string_array(dev, "gpio-line-names",
						names, count);
	if (ret < 0) {
		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
		kfree(names);
		return ret;
	}

	for (i = 0; i < count; i++)
		gdev->descs[i].name = names[i];

	kfree(names);

	return 0;
}

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

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

	/* Assume by default all GPIOs are valid */
	bitmap_fill(p, gc->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 *gc)
{
	bitmap_free(gc->valid_mask);
	gc->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 *gc,
				unsigned int offset)
{
	/* No mask means all valid */
	if (likely(!gc->valid_mask))
		return true;
	return test_bit(offset, gc->valid_mask);
}
EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);

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

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

#ifdef CONFIG_GPIO_CDEV
#define gcdev_register(gdev, devt)	gpiolib_cdev_register((gdev), (devt))
#define gcdev_unregister(gdev)		gpiolib_cdev_unregister((gdev))
#else
/*
 * gpiolib_cdev_register() indirectly calls device_add(), which is still
 * required even when cdev is not selected.
 */
#define gcdev_register(gdev, devt)	device_add(&(gdev)->dev)
#define gcdev_unregister(gdev)		device_del(&(gdev)->dev)
#endif

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

	ret = gcdev_register(gdev, gpio_devt);
	if (ret)
		return ret;

	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;
	dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
		gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");

	return 0;

err_remove_device:
	gcdev_unregister(gdev);
	return ret;
}

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

	desc = gpiochip_get_desc(gc, hog->chip_hwnum);
	if (IS_ERR(desc)) {
		chip_err(gc, "%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)
		gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n",
			  __func__, gc->label, hog->chip_hwnum, rv);
}

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

	mutex_lock(&gpio_machine_hogs_mutex);

	list_for_each_entry(hog, &gpio_machine_hogs, list) {
		if (!strcmp(gc->label, hog->chip_label))
			gpiochip_machine_hog(gc, 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)
			dev_err(&gdev->dev,
				"Failed to initialize gpio device (%d)\n", ret);
	}
}

int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
			       struct lock_class_key *lock_key,
			       struct lock_class_key *request_key)
{
	unsigned long	flags;
	int		ret = 0;
	unsigned	i;
	int		base = gc->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 = gc;
	gc->gpiodev = gdev;
	if (gc->parent) {
		gdev->dev.parent = gc->parent;
		gdev->dev.of_node = gc->parent->of_node;
	}

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

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

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

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

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

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

	gdev->ngpio = gc->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(gc->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.
		 */
		gc->base = base;
	}
	gdev->base = base;

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

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

	spin_unlock_irqrestore(&gpio_lock, flags);

	BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);

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

	if (gc->names)
		ret = gpiochip_set_desc_names(gc);
	else
		ret = devprop_gpiochip_set_names(gc);
	if (ret)
		goto err_remove_from_list;

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

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

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

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

		if (gc->get_direction && gpiochip_line_is_valid(gc, i)) {
			assign_bit(FLAG_IS_OUT,
				   &desc->flags, !gc->get_direction(gc, i));
		} else {
			assign_bit(FLAG_IS_OUT,
				   &desc->flags, !gc->direction_input);
		}
	}

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

	acpi_gpiochip_add(gc);

	machine_gpiochip_add(gc);

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

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

	ret = gpiochip_add_irqchip(gc, 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(gc);
err_remove_irqchip_mask:
	gpiochip_irqchip_free_valid_mask(gc);
err_remove_acpi_chip:
	acpi_gpiochip_remove(gc);
err_remove_of_chip:
	gpiochip_free_hogs(gc);
	of_gpiochip_remove(gc);
err_free_gpiochip_mask:
	gpiochip_remove_pin_ranges(gc);
	gpiochip_free_valid_mask(gc);
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_free(&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,
	       gc->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
 * @gc: GPIO chip
 *
 * Returns:
 * The per-subdriver data for the chip.
 */
void *gpiochip_get_data(struct gpio_chip *gc)
{
	return gc->gpiodev->data;
}
EXPORT_SYMBOL_GPL(gpiochip_get_data);

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

	/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
	gpiochip_sysfs_unregister(gdev);
	gpiochip_free_hogs(gc);
	/* Numb the device, cancelling all outstanding operations */
	gdev->chip = NULL;
	gpiochip_irqchip_remove(gc);
	acpi_gpiochip_remove(gc);
	of_gpiochip_remove(gc);
	gpiochip_remove_pin_ranges(gc);
	gpiochip_free_valid_mask(gc);
	/*
	 * 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++) {
		if (gpiochip_is_requested(gc, i))
			break;
	}
	spin_unlock_irqrestore(&gpio_lock, flags);

	if (i != gdev->ngpio)
		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.
	 */
	gcdev_unregister(gdev);
	put_device(&gdev->dev);
}
EXPORT_SYMBOL_GPL(gpiochip_remove);

/**
 * 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 *gc,
					     void *data))
{
	struct gpio_device *gdev;
	struct gpio_chip *gc = 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)) {
			gc = gdev->chip;
			break;
		}

	spin_unlock_irqrestore(&gpio_lock, flags);

	return gc;
}
EXPORT_SYMBOL_GPL(gpiochip_find);

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

	return !strcmp(gc->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 *gc)
{
	bitmap_free(gc->irq.valid_mask);
	gc->irq.valid_mask = NULL;
}

bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc,
				unsigned int offset)
{
	if (!gpiochip_line_is_valid(gc, offset))
		return false;
	/* No mask means all valid */
	if (likely(!gc->irq.valid_mask))
		return true;
	return test_bit(offset, gc->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
 * cascaded 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_nested_irqchip() - connects a nested irqchip to a gpiochip
 * @gc: 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 *gc,
				 struct irq_chip *irqchip,
				 unsigned int parent_irq)
{
	gpiochip_set_cascaded_irqchip(gc, 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;
	void *parent_arg;
	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_dbg(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_dbg(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);

	/* This parent only handles asserted level IRQs */
	parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type);
	if (!parent_arg)
		return -ENOMEM;

	chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n",
		  irq, parent_hwirq);
	irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key);
	ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg);
	/*
	 * If the parent irqdomain is msi, the interrupts have already
	 * been allocated, so the EEXIST is good.
	 */
	if (irq_domain_is_msi(d->parent) && (ret == -EEXIST))
		ret = 0;
	if (ret)
		chip_err(gc,
			 "failed to allocate parent hwirq %d for hwirq %lu\n",
			 parent_hwirq, hwirq);

	kfree(parent_arg);
	return ret;
}

static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc,
						      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_alloc_arg)
		gc->irq.populate_parent_alloc_arg =
			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 *gc,
					     unsigned int parent_hwirq,
					     unsigned int parent_type)
{
	struct irq_fwspec *fwspec;

	fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
	if (!fwspec)
		return NULL;

	fwspec->fwnode = gc->irq.parent_domain->fwnode;
	fwspec->param_count = 2;
	fwspec->param[0] = parent_hwirq;
	fwspec->param[1] = parent_type;

	return fwspec;
}
EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell);

void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc,
					      unsigned int parent_hwirq,
					      unsigned int parent_type)
{
	struct irq_fwspec *fwspec;

	fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
	if (!fwspec)
		return NULL;

	fwspec->fwnode = gc->irq.parent_domain->fwnode;
	fwspec->param_count = 4;
	fwspec->param[0] = 0;
	fwspec->param[1] = parent_hwirq;
	fwspec->param[2] = 0;
	fwspec->param[3] = parent_type;

	return fwspec;
}
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 *gc = d->host_data;
	int ret = 0;

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

	irq_set_chip_data(irq, gc);
	/*
	 * 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, gc->irq.lock_key, gc->irq.request_key);
	irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler);
	/* Chips that use nested thread handlers have them marked */
	if (gc->irq.threaded)
		irq_set_nested_thread(irq, 1);
	irq_set_noprobe(irq);

	if (gc->irq.num_parents == 1)
		ret = irq_set_parent(irq, gc->irq.parents[0]);
	else if (gc->irq.map)
		ret = irq_set_parent(irq, gc->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 (gc->irq.default_type != IRQ_TYPE_NONE)
		irq_set_irq_type(irq, gc->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 *gc = d->host_data;

	if (gc->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 *gc = domain->host_data;

	return gpiochip_lock_as_irq(gc, 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 *gc = domain->host_data;

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

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

	if (!gpiochip_irqchip_irq_valid(gc, 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] = gc->irq.child_offset_to_irq(gc, 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 *gc = irq_data_get_irq_chip_data(d);

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

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

	gpiochip_relres_irq(gc, d->hwirq);
}

static void gpiochip_irq_mask(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);

	if (gc->irq.irq_mask)
		gc->irq.irq_mask(d);
	gpiochip_disable_irq(gc, d->hwirq);
}

static void gpiochip_irq_unmask(struct irq_data *d)
{
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);

	gpiochip_enable_irq(gc, d->hwirq);
	if (gc->irq.irq_unmask)
		gc->irq.irq_unmask(d);
}

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

	gpiochip_enable_irq(gc, d->hwirq);
	gc->irq.irq_enable(d);
}

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

	gc->irq.irq_disable(d);
	gpiochip_disable_irq(gc, d->hwirq);
}

static void gpiochip_set_irq_hooks(struct gpio_chip *gc)
{
	struct irq_chip *irqchip = gc->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(gc->irq.irq_enable))
		return;
	/* Check if the irqchip already has this hook... */
	if (irqchip->irq_enable == gpiochip_irq_enable ||
		irqchip->irq_mask == gpiochip_irq_mask) {
		/*
		 * ...and if so, give a gentle warning that this is bad
		 * practice.
		 */
		chip_info(gc,
			  "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n");
		return;
	}

	if (irqchip->irq_disable) {
		gc->irq.irq_disable = irqchip->irq_disable;
		irqchip->irq_disable = gpiochip_irq_disable;
	} else {
		gc->irq.irq_mask = irqchip->irq_mask;
		irqchip->irq_mask = gpiochip_irq_mask;
	}

	if (irqchip->irq_enable) {
		gc->irq.irq_enable = irqchip->irq_enable;
		irqchip->irq_enable = gpiochip_irq_enable;
	} else {
		gc->irq.irq_unmask = irqchip->irq_unmask;
		irqchip->irq_unmask = gpiochip_irq_unmask;
	}
}

/**
 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip
 * @gc: 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 *gc,
				struct lock_class_key *lock_key,
				struct lock_class_key *request_key)
{
	struct irq_chip *irqchip = gc->irq.chip;
	const struct irq_domain_ops *ops = NULL;
	struct device_node *np;
	unsigned int type;
	unsigned int i;

	if (!irqchip)
		return 0;

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

	np = gc->gpiodev->dev.of_node;
	type = gc->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(gc->parent) && type != IRQ_TYPE_NONE) {
		acpi_handle_warn(ACPI_HANDLE(gc->parent),
				 "Ignoring %u default trigger\n", type);
		type = IRQ_TYPE_NONE;
	}

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

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

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

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

		for (i = 0; i < gc->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(gc->irq.parents[i],
							 gc->irq.parent_handler,
							 data);
		}
	}

	gpiochip_set_irq_hooks(gc);

	acpi_gpiochip_request_interrupts(gc);

	return 0;
}

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

	acpi_gpiochip_free_interrupts(gc);

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

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

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

		irq_domain_remove(gc->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 = gc->irq.irq_enable;
			irqchip->irq_disable = gc->irq.irq_disable;
		}
	}
	gc->irq.irq_enable = NULL;
	gc->irq.irq_disable = NULL;
	gc->irq.chip = NULL;

	gpiochip_irqchip_free_valid_mask(gc);
}

/**
 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip
 * @gc: 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 *gc,
			     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 (!gc || !irqchip)
		return -EINVAL;

	if (!gc->parent) {
		chip_err(gc, "missing gpiochip .dev parent pointer\n");
		return -EINVAL;
	}
	gc->irq.threaded = threaded;
	of_node = gc->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 gc->parent->of_node
	 * everywhere
	 */
	if (gc->of_node)
		of_node = gc->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(gc->parent) && type != IRQ_TYPE_NONE) {
		acpi_handle_warn(ACPI_HANDLE(gc->parent),
				 "Ignoring %d default trigger\n", type);
		type = IRQ_TYPE_NONE;
	}

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

	gpiochip_set_irq_hooks(gc);

	acpi_gpiochip_request_interrupts(gc);

	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key);

/**
 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip
 * @gc: the gpiochip to add the irqchip to
 * @domain: the irqdomain to add to the gpiochip
 *
 * This function adds an IRQ domain to the gpiochip.
 */
int gpiochip_irqchip_add_domain(struct gpio_chip *gc,
				struct irq_domain *domain)
{
	if (!domain)
		return -EINVAL;

	gc->to_irq = gpiochip_to_irq;
	gc->irq.domain = domain;

	return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain);

#else /* CONFIG_GPIOLIB_IRQCHIP */

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

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

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

#endif /* CONFIG_GPIOLIB_IRQCHIP */

/**
 * gpiochip_generic_request() - request the gpio function for a pin
 * @gc: the gpiochip owning the GPIO
 * @offset: the offset of the GPIO to request for GPIO function
 */
int gpiochip_generic_request(struct gpio_chip *gc, unsigned offset)
{
#ifdef CONFIG_PINCTRL
	if (list_empty(&gc->gpiodev->pin_ranges))
		return 0;
#endif

	return pinctrl_gpio_request(gc->gpiodev->base + offset);
}
EXPORT_SYMBOL_GPL(gpiochip_generic_request);

/**
 * gpiochip_generic_free() - free the gpio function from a pin
 * @gc: 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 *gc, unsigned offset)
{
#ifdef CONFIG_PINCTRL
	if (list_empty(&gc->gpiodev->pin_ranges))
		return;
#endif

	pinctrl_gpio_free(gc->gpiodev->base + offset);
}
EXPORT_SYMBOL_GPL(gpiochip_generic_free);

/**
 * gpiochip_generic_config() - apply configuration for a pin
 * @gc: 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 *gc, unsigned offset,
			    unsigned long config)
{
	return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config);
}
EXPORT_SYMBOL_GPL(gpiochip_generic_config);

#ifdef CONFIG_PINCTRL

/**
 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
 * @gc: 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 *gc,
			struct pinctrl_dev *pctldev,
			unsigned int gpio_offset, const char *pin_group)
{
	struct gpio_pin_range *pin_range;
	struct gpio_device *gdev = gc->gpiodev;
	int ret;

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

	/* Use local offset as range ID */
	pin_range->range.id = gpio_offset;
	pin_range->range.gc = gc;
	pin_range->range.name = gc->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(gc, "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
 * @gc: 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 *gc, 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 = gc->gpiodev;
	int ret;

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

	/* Use local offset as range ID */
	pin_range->range.id = gpio_offset;
	pin_range->range.gc = gc;
	pin_range->range.name = gc->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(gc, "could not create pin range\n");
		kfree(pin_range);
		return ret;
	}
	chip_dbg(gc, "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
 * @gc: the chip to remove all the mappings for
 */
void gpiochip_remove_pin_ranges(struct gpio_chip *gc)
{
	struct gpio_pin_range *pin_range, *tmp;
	struct gpio_device *gdev = gc->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	*gc = 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 (gc->request) {
		/* gc->request may sleep */
		spin_unlock_irqrestore(&gpio_lock, flags);
		offset = gpio_chip_hwgpio(desc);
		if (gpiochip_line_is_valid(gc, offset))
			ret = gc->request(gc, 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 (gc->get_direction) {
		/* gc->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	*gc;

	might_sleep();

	gpiod_unexport(desc);

	spin_lock_irqsave(&gpio_lock, flags);

	gc = desc->gdev->chip;
	if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) {
		if (gc->free) {
			spin_unlock_irqrestore(&gpio_lock, flags);
			might_sleep_if(gc->can_sleep);
			gc->free(gc, 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_EDGE_RISING, &desc->flags);
		clear_bit(FLAG_EDGE_FALLING, &desc->flags);
		clear_bit(FLAG_IS_HOGGED, &desc->flags);
#ifdef CONFIG_OF_DYNAMIC
		desc->hog = NULL;
#endif
#ifdef CONFIG_GPIO_CDEV
		WRITE_ONCE(desc->debounce_period_us, 0);
#endif
		ret = true;
	}

	spin_unlock_irqrestore(&gpio_lock, flags);
	blocking_notifier_call_chain(&desc->gdev->notifier,
				     GPIOLINE_CHANGED_RELEASED, desc);

	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
 * @gc: 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 *gc, unsigned offset)
{
	struct gpio_desc *desc;

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

	desc = gpiochip_get_desc(gc, offset);
	if (IS_ERR(desc))
		return NULL;

	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
 * @gc: 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 *gc,
					    unsigned int hwnum,
					    const char *label,
					    enum gpio_lookup_flags lflags,
					    enum gpiod_flags dflags)
{
	struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum);
	int ret;

	if (IS_ERR(desc)) {
		chip_err(gc, "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(gc, "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_do_set_config(struct gpio_chip *gc, unsigned int offset,
			      unsigned long config)
{
	if (!gc->set_config)
		return -ENOTSUPP;

	return gc->set_config(gc, offset, config);
}

static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode)
{
	struct gpio_chip *gc = desc->gdev->chip;
	unsigned long config;
	unsigned arg;

	switch (mode) {
	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 gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
}

static int gpio_set_bias(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(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	*gc;
	int			ret = 0;

	VALIDATE_DESC(desc);
	gc = 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 (!gc->get && gc->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 (gc->direction_input) {
		ret = gc->direction_input(gc, gpio_chip_hwgpio(desc));
	} else if (gc->get_direction &&
		  (gc->get_direction(gc, 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(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)
{
	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;
	}

	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
		/* First see if we can enable open drain in hardware */
		ret = gpio_set_config(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(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(desc, PIN_CONFIG_DRIVE_PUSH_PULL);
	}

set_output_value:
	ret = gpio_set_bias(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_config - sets @config for a GPIO
 * @desc: descriptor of the GPIO for which to set the configuration
 * @config: Same packed config format as generic pinconf
 *
 * Returns:
 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
 * configuration.
 */
int gpiod_set_config(struct gpio_desc *desc, unsigned long config)
{
	struct gpio_chip *gc;

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

	return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
}
EXPORT_SYMBOL_GPL(gpiod_set_config);

/**
 * 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)
{
	unsigned long config;

	config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
	return gpiod_set_config(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 *gc;
	unsigned long packed;
	int gpio;
	int rc;

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

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

	packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
					  !transitory);
	gpio = gpio_chip_hwgpio(desc);
	rc = gpio_do_set_config(gc, 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);

/**
 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not
 * @desc: the gpio descriptor to change
 */
void gpiod_toggle_active_low(struct gpio_desc *desc)
{
	VALIDATE_DESC_VOID(desc);
	change_bit(FLAG_ACTIVE_LOW, &desc->flags);
}
EXPORT_SYMBOL_GPL(gpiod_toggle_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	*gc;
	int offset;
	int value;

	gc = desc->gdev->chip;
	offset = gpio_chip_hwgpio(desc);
	value = gc->get ? gc->get(gc, 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 *gc,
				  unsigned long *mask, unsigned long *bits)
{
	if (gc->get_multiple) {
		return gc->get_multiple(gc, mask, bits);
	} else if (gc->get) {
		int i, value;

		for_each_set_bit(i, mask, gc->ngpio) {
			value = gc->get(gc, 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);

		i = find_first_zero_bit(array_info->get_mask, array_size);
		if (i == array_size)
			return 0;
	} else {
		array_info = NULL;
	}

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

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

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

		if (!can_sleep)
			WARN_ON(gc->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 == gc));

		ret = gpio_chip_get_multiple(gc, 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 *gc = desc->gdev->chip;
	int offset = gpio_chip_hwgpio(desc);

	if (value) {
		ret = gc->direction_input(gc, offset);
	} else {
		ret = gc->direction_output(gc, 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 *gc = desc->gdev->chip;
	int offset = gpio_chip_hwgpio(desc);

	if (value) {
		ret = gc->direction_output(gc, offset, 1);
		if (!ret)
			set_bit(FLAG_IS_OUT, &desc->flags);
	} else {
		ret = gc->direction_input(gc, 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	*gc;

	gc = desc->gdev->chip;
	trace_gpio_value(desc_to_gpio(desc), 0, value);
	gc->set(gc, 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;
 * @chip: the GPIO chip we operate on
 * @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 *gc,
				   unsigned long *mask, unsigned long *bits)
{
	if (gc->set_multiple) {
		gc->set_multiple(gc, mask, bits);
	} else {
		unsigned int i;

		/* set outputs if the corresponding mask bit is set */
		for_each_set_bit(i, mask, gc->ngpio)
			gc->set(gc, 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);

		i = find_first_zero_bit(array_info->set_mask, array_size);
		if (i == array_size)
			return 0;
	} else {
		array_info = NULL;
	}

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

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

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

		if (!can_sleep)
			WARN_ON(gc->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);
				__assign_bit(hwgpio, bits, value);
				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 == gc));
		/* push collected bits to outputs */
		if (count != 0)
			gpio_chip_set_multiple(gc, 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 *gc;
	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;

	gc = desc->gdev->chip;
	offset = gpio_chip_hwgpio(desc);
	if (gc->to_irq) {
		int retirq = gc->to_irq(gc, 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
 * @gc: 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 *gc, unsigned int offset)
{
	struct gpio_desc *desc;

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

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

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

	/* To be valid for IRQ the line needs to be input or open drain */
	if (test_bit(FLAG_IS_OUT, &desc->flags) &&
	    !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) {
		chip_err(gc,
			 "%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
 * @gc: 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 *gc, unsigned int offset)
{
	struct gpio_desc *desc;

	desc = gpiochip_get_desc(gc, 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 *gc, unsigned int offset)
{
	struct gpio_desc *desc = gpiochip_get_desc(gc, 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 *gc, unsigned int offset)
{
	struct gpio_desc *desc = gpiochip_get_desc(gc, offset);

	if (!IS_ERR(desc) &&
	    !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) {
		/*
		 * We must not be output when using IRQ UNLESS we are
		 * open drain.
		 */
		WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) &&
			!test_bit(FLAG_OPEN_DRAIN, &desc->flags));
		set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags);
	}
}
EXPORT_SYMBOL_GPL(gpiochip_enable_irq);

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

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

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

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

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

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

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

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

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

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

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

	return !test_bit(FLAG_TRANSITORY, &gc->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 *gc;
	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.
		 */
		gc = find_chip_by_name(hog->chip_label);
		if (gc)
			gpiochip_machine_hog(gc, 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->key; p++) {
		struct gpio_chip *gc;

		/* 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;

		if (p->chip_hwnum == U16_MAX) {
			desc = gpio_name_to_desc(p->key);
			if (desc) {
				*flags = p->flags;
				return desc;
			}

			dev_warn(dev, "cannot find GPIO line %s, deferring\n",
				 p->key);
			return ERR_PTR(-EPROBE_DEFER);
		}

		gc = find_chip_by_name(p->key);

		if (!gc) {
			/*
			 * As the lookup table indicates a chip with
			 * p->key 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->key);
			return ERR_PTR(-EPROBE_DEFER);
		}

		if (gc->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, gc->ngpio - 1,
				gc->label);
			return ERR_PTR(-EINVAL);
		}

		desc = gpiochip_get_desc(gc, 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->key; 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)) {
		gpiod_dbg(desc, "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);
	}

	blocking_notifier_call_chain(&desc->gdev->notifier,
				     GPIOLINE_CHANGED_REQUESTED, desc);

	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);
	}

	blocking_notifier_call_chain(&desc->gdev->notifier,
				     GPIOLINE_CHANGED_REQUESTED, desc);

	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 *gc;
	struct gpio_desc *local_desc;
	int hwnum;
	int ret;

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

	local_desc = gpiochip_request_own_desc(gc, 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, gc->label, hwnum, ret);
		return ret;
	}

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

	gpiod_info(desc, "hogged as %s%s\n",
		(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
 * @gc:	gpio chip to act on
 */
static void gpiochip_free_hogs(struct gpio_chip *gc)
{
	int id;

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

		gc = 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(gc->ngpio > count ?
						    gc->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 = gc;
			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 != gc) {
			__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(gc, descs->ndescs) ||
			    gpiochip_line_is_open_source(gc, 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 (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_NAME);
	if (ret < 0) {
		pr_err("gpiolib: failed to allocate char dev region\n");
		bus_unregister(&gpio_bus_type);
		return ret;
	}

	gpiolib_initialized = true;
	gpiochip_setup_devs();

#if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO)
	WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
#endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */

	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	*gc = 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 ",
			gc->get ? (gc->get(gc, 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 *gc = gdev->chip;
	struct device *parent;

	if (!gc) {
		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 = gc->parent;
	if (parent)
		seq_printf(s, ", parent: %s/%s",
			   parent->bus ? parent->bus->name : "no-bus",
			   dev_name(parent));
	if (gc->label)
		seq_printf(s, ", %s", gc->label);
	if (gc->can_sleep)
		seq_printf(s, ", can sleep");
	seq_printf(s, ":\n");

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

	return 0;
}

static const struct seq_operations gpiolib_sops = {
	.start = gpiolib_seq_start,
	.next = gpiolib_seq_next,
	.stop = gpiolib_seq_stop,
	.show = gpiolib_seq_show,
};
DEFINE_SEQ_ATTRIBUTE(gpiolib);

static int __init gpiolib_debugfs_init(void)
{
	/* /sys/kernel/debug/gpio */
	debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
	return 0;
}
subsys_initcall(gpiolib_debugfs_init);

#endif	/* DEBUG_FS */