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
fdtbus_register_syscon(device_t dev,int phandle,struct syscon * syscon)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 *
fdtbus_get_syscon(int phandle)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 *
fdtbus_syscon_acquire(int phandle,const char * prop)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 *
fdtbus_syscon_lookup(int phandle)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