1 /* $NetBSD: fdt_i2c.c,v 1.12 2022/02/23 07:55:55 skrll Exp $ */
2
3 /*-
4 * Copyright (c) 2015 Jared D. 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_i2c.c,v 1.12 2022/02/23 07:55:55 skrll 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 fdtbus_i2c_controller {
41 i2c_tag_t i2c_tag;
42 int i2c_phandle;
43
44 LIST_ENTRY(fdtbus_i2c_controller) i2c_next;
45 };
46
47 static LIST_HEAD(, fdtbus_i2c_controller) fdtbus_i2c_controllers =
48 LIST_HEAD_INITIALIZER(fdtbus_i2c_controllers);
49
50 int
fdtbus_register_i2c_controller(i2c_tag_t tag,int phandle)51 fdtbus_register_i2c_controller(i2c_tag_t tag, int phandle)
52 {
53 struct fdtbus_i2c_controller *i2c;
54
55 i2c = kmem_alloc(sizeof(*i2c), KM_SLEEP);
56 i2c->i2c_tag = tag;
57 i2c->i2c_phandle = phandle;
58
59 LIST_INSERT_HEAD(&fdtbus_i2c_controllers, i2c, i2c_next);
60
61 return 0;
62 }
63
64 static struct fdtbus_i2c_controller *
fdtbus_get_i2c_controller(int phandle)65 fdtbus_get_i2c_controller(int phandle)
66 {
67 struct fdtbus_i2c_controller *i2c;
68
69 LIST_FOREACH(i2c, &fdtbus_i2c_controllers, i2c_next) {
70 if (i2c->i2c_phandle == phandle)
71 return i2c;
72 }
73
74 return NULL;
75 }
76
77 i2c_tag_t
fdtbus_i2c_get_tag(int phandle)78 fdtbus_i2c_get_tag(int phandle)
79 {
80 struct fdtbus_i2c_controller *i2c;
81
82 i2c = fdtbus_get_i2c_controller(phandle);
83 if (i2c == NULL)
84 return NULL;
85
86 return i2c->i2c_tag;
87 }
88
89 i2c_tag_t
fdtbus_i2c_acquire(int phandle,const char * prop)90 fdtbus_i2c_acquire(int phandle, const char *prop)
91 {
92 int i2c_phandle;
93
94 i2c_phandle = fdtbus_get_phandle(phandle, prop);
95 if (i2c_phandle == -1)
96 return NULL;
97
98 return fdtbus_i2c_get_tag(i2c_phandle);
99 }
100
101 device_t
fdtbus_attach_i2cbus(device_t dev,int phandle,i2c_tag_t tag,cfprint_t print)102 fdtbus_attach_i2cbus(device_t dev, int phandle, i2c_tag_t tag, cfprint_t print)
103 {
104 struct i2cbus_attach_args iba;
105 prop_dictionary_t devs, props;
106 device_t ret;
107 u_int address_cells;
108
109 devs = prop_dictionary_create();
110 if (of_getprop_uint32(phandle, "#address-cells", &address_cells))
111 address_cells = 1;
112
113 of_enter_i2c_devs(devs, phandle, address_cells * 4, 0);
114
115 memset(&iba, 0, sizeof(iba));
116 iba.iba_tag = tag;
117 iba.iba_child_devices = prop_dictionary_get(devs, "i2c-child-devices");
118 if (iba.iba_child_devices)
119 prop_object_retain(iba.iba_child_devices);
120 prop_object_release(devs);
121
122 props = device_properties(dev);
123 prop_dictionary_set_bool(props, "i2c-no-indirect-config", true);
124
125 ret = config_found(dev, &iba, print,
126 CFARGS(.iattr = "i2cbus"));
127 if (iba.iba_child_devices)
128 prop_object_release(iba.iba_child_devices);
129
130 return ret;
131 }
132