1 /* $NetBSD: fdt_syscon.c,v 1.3 2018/06/30 20:16:56 jmcneill Exp $ */ 2 3 /*- 4 * Copyright (c) 2018 Jared McNeill <jmcneill@invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: fdt_syscon.c,v 1.3 2018/06/30 20:16:56 jmcneill Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/bus.h> 34 #include <sys/kmem.h> 35 #include <sys/queue.h> 36 37 #include <libfdt.h> 38 #include <dev/fdt/fdtvar.h> 39 40 struct syscon; 41 42 struct fdtbus_syscon { 43 device_t sc_dev; 44 int sc_phandle; 45 struct syscon *sc_syscon; 46 47 LIST_ENTRY(fdtbus_syscon) sc_next; 48 }; 49 50 static LIST_HEAD(, fdtbus_syscon) fdtbus_syscons = 51 LIST_HEAD_INITIALIZER(fdtbus_syscons); 52 53 int 54 fdtbus_register_syscon(device_t dev, int phandle, 55 struct syscon *syscon) 56 { 57 struct fdtbus_syscon *sc; 58 59 sc = kmem_alloc(sizeof(*sc), KM_SLEEP); 60 sc->sc_dev = dev; 61 sc->sc_phandle = phandle; 62 sc->sc_syscon = syscon; 63 64 LIST_INSERT_HEAD(&fdtbus_syscons, sc, sc_next); 65 66 return 0; 67 } 68 69 static struct fdtbus_syscon * 70 fdtbus_get_syscon(int phandle) 71 { 72 struct fdtbus_syscon *sc; 73 74 LIST_FOREACH(sc, &fdtbus_syscons, sc_next) { 75 if (sc->sc_phandle == phandle) 76 return sc; 77 } 78 79 return NULL; 80 } 81 82 struct syscon * 83 fdtbus_syscon_acquire(int phandle, const char *prop) 84 { 85 struct fdtbus_syscon *sc; 86 int sc_phandle; 87 88 sc_phandle = fdtbus_get_phandle(phandle, prop); 89 if (sc_phandle < 0) 90 return NULL; 91 92 sc = fdtbus_get_syscon(sc_phandle); 93 if (sc == NULL) 94 return NULL; 95 96 return sc->sc_syscon; 97 } 98 99 struct syscon * 100 fdtbus_syscon_lookup(int phandle) 101 { 102 struct fdtbus_syscon *sc; 103 104 sc = fdtbus_get_syscon(phandle); 105 if (sc == NULL) 106 return NULL; 107 108 return sc->sc_syscon; 109 } 110