1 /*-
2 * Copyright (c) 1998, 2001 Nicolas Souchu
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: releng/5.0/sys/dev/iicbus/iicbus.c 93023 2002-03-23 15:49:15Z nsouch $
27 *
28 */
29
30 /*
31 * Autoconfiguration and support routines for the Philips serial I2C bus
32 */
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
38 #include <sys/bus.h>
39
40
41 #include <dev/iicbus/iiconf.h>
42 #include <dev/iicbus/iicbus.h>
43
44 #include "iicbus_if.h"
45
46 #define DEVTOIICBUS(dev) ((struct iicbus_device*)device_get_ivars(dev))
47
48 static devclass_t iicbus_devclass;
49
50 /*
51 * Device methods
52 */
53 static int iicbus_probe(device_t);
54 static int iicbus_attach(device_t);
55 static int iicbus_detach(device_t);
56 static int iicbus_add_child(device_t dev, int order, const char *name, int unit);
57
58 static device_method_t iicbus_methods[] = {
59 /* device interface */
60 DEVMETHOD(device_probe, iicbus_probe),
61 DEVMETHOD(device_attach, iicbus_attach),
62 DEVMETHOD(device_detach, iicbus_detach),
63
64 /* bus interface */
65 DEVMETHOD(bus_add_child, iicbus_add_child),
66 DEVMETHOD(bus_driver_added, bus_generic_driver_added),
67 DEVMETHOD(bus_print_child, bus_generic_print_child),
68
69 { 0, 0 }
70 };
71
72 static driver_t iicbus_driver = {
73 "iicbus",
74 iicbus_methods,
75 sizeof(struct iicbus_softc),
76 };
77
78 static int
79 iicbus_probe(device_t dev)
80 {
81 device_set_desc(dev, "Philips I2C bus");
82
83 return (0);
84 }
85
86 #if 0
87 static int
88 iic_probe_device(device_t dev, u_char addr)
89 {
90 int count;
91 char byte;
92
93 if ((addr & 1) == 0) {
94 /* is device writable? */
95 if (!iicbus_start(dev, (u_char)addr, 0)) {
96 iicbus_stop(dev);
97 return (1);
98 }
99 } else {
100 /* is device readable? */
101 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count))
102 return (1);
103 }
104
105 return (0);
106 }
107 #endif
108
109 /*
110 * We add all the devices which we know about.
111 * The generic attach routine will attach them if they are alive.
112 */
113 static int
114 iicbus_attach(device_t dev)
115 {
116 iicbus_reset(dev, IIC_FASTEST, 0, NULL);
117
118 /* device probing is meaningless since the bus is supposed to be
119 * hot-plug. Moreover, some I2C chips do not appreciate random
120 * accesses like stop after start to fast, reads for less than
121 * x bytes...
122 */
123 #if 0
124 printf("Probing for devices on iicbus%d:", device_get_unit(dev));
125
126 /* probe any devices */
127 for (addr = FIRST_SLAVE_ADDR; addr <= LAST_SLAVE_ADDR; addr++) {
128 if (iic_probe_device(dev, (u_char)addr)) {
129 printf(" <%x>", addr);
130 }
131 }
132 printf("\n");
133 #endif
134
135 /* attach any known device */
136 device_add_child(dev, NULL, -1);
137
138 bus_generic_attach(dev);
139
140 return (0);
141 }
142
143 static int
144 iicbus_detach(device_t dev)
145 {
146 iicbus_reset(dev, IIC_FASTEST, 0, NULL);
147
148 bus_generic_detach(dev);
149
150 return (0);
151 }
152
153 static int
154 iicbus_add_child(device_t dev, int order, const char *name, int unit)
155 {
156 device_add_child_ordered(dev, order, name, unit);
157
158 bus_generic_attach(dev);
159
160 return (0);
161 }
162
163 int
164 iicbus_generic_intr(device_t dev, int event, char *buf)
165 {
166 return (0);
167 }
168
169 int
170 iicbus_null_callback(device_t dev, int index, caddr_t data)
171 {
172 return (0);
173 }
174
175 int
176 iicbus_null_repeated_start(device_t dev, u_char addr)
177 {
178 return (IIC_ENOTSUPP);
179 }
180
181 DRIVER_MODULE(iicbus, pcf, iicbus_driver, iicbus_devclass, 0, 0);
182 DRIVER_MODULE(iicbus, iicbb, iicbus_driver, iicbus_devclass, 0, 0);
183 DRIVER_MODULE(iicbus, bti2c, iicbus_driver, iicbus_devclass, 0, 0);
184 MODULE_VERSION(iicbus, IICBUS_MODVER);
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