2 * Copyright (c) 1998, 2001 Nicolas Souchu
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
26 * $FreeBSD: src/sys/dev/iicbus/iicbus.c,v 1.29 2009/02/10 22:50:23 imp Exp $
27 * $DragonFly: src/sys/bus/iicbus/iicbus.c,v 1.5 2006/12/22 23:12:16 swildner Exp $
32 * Autoconfiguration and support routines for the Philips serial I2C bus
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/module.h>
41 #include <bus/iicbus/iiconf.h>
42 #include <bus/iicbus/iicbus.h>
44 #include "iicbus_if.h"
46 #define DEVTOIICBUS(dev) ((struct iicbus_device*)device_get_ivars(dev))
48 devclass_t iicbus_devclass;
50 /* See comments below for why auto-scanning is a bad idea. */
56 static int iicbus_probe(device_t);
57 static int iicbus_attach(device_t);
58 static int iicbus_detach(device_t);
59 static int iicbus_add_child(device_t dev, int order, const char *name, int unit);
61 static device_method_t iicbus_methods[] = {
62 /* device interface */
63 DEVMETHOD(device_probe, iicbus_probe),
64 DEVMETHOD(device_attach, iicbus_attach),
65 DEVMETHOD(device_detach, iicbus_detach),
68 DEVMETHOD(bus_add_child, iicbus_add_child),
69 DEVMETHOD(bus_driver_added, bus_generic_driver_added),
70 DEVMETHOD(bus_print_child, bus_generic_print_child),
72 DEVMETHOD(iicbus_transfer, iicbus_transfer_gen),
77 driver_t iicbus_driver = {
80 sizeof(struct iicbus_softc),
84 iicbus_probe(device_t dev)
87 device_set_desc(dev, "Philips I2C bus");
89 /* Allow other subclasses to override this driver. */
90 return (BUS_PROBE_GENERIC);
95 iic_probe_device(device_t dev, u_char addr)
100 if ((addr & 1) == 0) {
101 /* is device writable? */
102 if (!iicbus_start(dev, (u_char)addr, 0)) {
107 /* is device readable? */
108 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count))
117 * We add all the devices which we know about.
118 * The generic attach routine will attach them if they are alive.
121 iicbus_attach(device_t dev)
127 iicbus_reset(dev, IIC_FASTEST, 0, NULL);
129 /* device probing is meaningless since the bus is supposed to be
130 * hot-plug. Moreover, some I2C chips do not appreciate random
131 * accesses like stop after start to fast, reads for less than
135 kprintf("Probing for devices on iicbus%d:", device_get_unit(dev));
137 /* probe any devices */
138 for (addr = 16; addr < 240; addr++) {
139 if (iic_probe_device(dev, (u_char)addr)) {
140 kprintf(" <%x>", addr);
146 device_add_child(dev, "ic", -1);
147 device_add_child(dev, "iic", -1);
148 device_add_child(dev, "iicsmb", -1);
150 /* attach any known device */
151 device_add_child(dev, "iic", -1);
153 bus_generic_attach(dev);
159 iicbus_detach(device_t dev)
161 iicbus_reset(dev, IIC_FASTEST, 0, NULL);
162 bus_generic_detach(dev);
167 iicbus_add_child(device_t dev, int order, const char *name, int unit)
170 device_add_child_ordered(dev, order, name, unit);
171 bus_generic_attach(dev);
176 iicbus_generic_intr(device_t dev, int event, char *buf)
183 iicbus_null_callback(device_t dev, int index, caddr_t data)
190 iicbus_null_repeated_start(device_t dev, u_char addr)
193 return (IIC_ENOTSUPP);
196 DRIVER_MODULE(iicbus, iicbb, iicbus_driver, iicbus_devclass, 0, 0);
197 MODULE_VERSION(iicbus, IICBUS_MODVER);