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 $
30 * Autoconfiguration and support routines for the Philips serial I2C bus
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/module.h>
39 #include <bus/iicbus/iiconf.h>
40 #include <bus/iicbus/iicbus.h>
42 #include "iicbus_if.h"
44 #define DEVTOIICBUS(dev) ((struct iicbus_device*)device_get_ivars(dev))
46 devclass_t iicbus_devclass
;
48 /* See comments below for why auto-scanning is a bad idea. */
54 static int iicbus_probe(device_t
);
55 static int iicbus_attach(device_t
);
56 static int iicbus_detach(device_t
);
57 static int iicbus_add_child(device_t dev
, int order
, const char *name
, int unit
);
59 static device_method_t iicbus_methods
[] = {
60 /* device interface */
61 DEVMETHOD(device_probe
, iicbus_probe
),
62 DEVMETHOD(device_attach
, iicbus_attach
),
63 DEVMETHOD(device_detach
, iicbus_detach
),
66 DEVMETHOD(bus_add_child
, iicbus_add_child
),
67 DEVMETHOD(bus_driver_added
, bus_generic_driver_added
),
68 DEVMETHOD(bus_print_child
, bus_generic_print_child
),
70 DEVMETHOD(iicbus_transfer
, iicbus_transfer_gen
),
75 driver_t iicbus_driver
= {
78 sizeof(struct iicbus_softc
),
82 iicbus_probe(device_t dev
)
85 device_set_desc(dev
, "Philips I2C bus");
87 /* Allow other subclasses to override this driver. */
88 return (BUS_PROBE_GENERIC
);
93 iic_probe_device(device_t dev
, u_char addr
)
98 if ((addr
& 1) == 0) {
99 /* is device writable? */
100 if (!iicbus_start(dev
, addr
, 0)) {
105 /* is device readable? */
106 if (!iicbus_block_read(dev
, addr
, &byte
, 1, &count
))
115 * We add all the devices which we know about.
116 * The generic attach routine will attach them if they are alive.
119 iicbus_attach(device_t dev
)
125 iicbus_reset(dev
, IIC_FASTEST
, 0, NULL
);
127 /* device probing is meaningless since the bus is supposed to be
128 * hot-plug. Moreover, some I2C chips do not appreciate random
129 * accesses like stop after start to fast, reads for less than
133 kprintf("Probing for devices on iicbus%d:", device_get_unit(dev
));
135 /* probe any devices */
136 for (addr
= 16; addr
< 240; addr
++) {
137 if (iic_probe_device(dev
, (u_char
)addr
)) {
138 kprintf(" <%x>", addr
);
144 device_add_child(dev
, "ic", -1);
145 device_add_child(dev
, "iic", -1);
146 device_add_child(dev
, "iicsmb", -1);
148 /* attach any known device */
149 device_add_child(dev
, "iic", -1);
151 bus_generic_attach(dev
);
157 iicbus_detach(device_t dev
)
159 iicbus_reset(dev
, IIC_FASTEST
, 0, NULL
);
160 bus_generic_detach(dev
);
165 iicbus_add_child(device_t dev
, int order
, const char *name
, int unit
)
168 device_add_child_ordered(dev
, order
, name
, unit
);
169 bus_generic_attach(dev
);
174 iicbus_generic_intr(device_t dev
, int event
, char *buf
)
181 iicbus_null_callback(device_t dev
, int index
, caddr_t data
)
188 iicbus_null_repeated_start(device_t dev
, u_char addr
)
191 return (IIC_ENOTSUPP
);
194 DRIVER_MODULE(iicbus
, iicbb
, iicbus_driver
, iicbus_devclass
, NULL
, NULL
);
195 MODULE_VERSION(iicbus
, IICBUS_MODVER
);