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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
31 * Autoconfiguration and support routines for the Philips serial I2C bus
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
43 #include <dev/iicbus/iiconf.h>
44 #include <dev/iicbus/iicbus.h>
46 #include "iicbus_if.h"
48 /* See comments below for why auto-scanning is a bad idea. */
52 iicbus_probe(device_t dev)
55 device_set_desc(dev, "Philips I2C bus");
57 /* Allow other subclasses to override this driver. */
58 return (BUS_PROBE_GENERIC);
63 iic_probe_device(device_t dev, u_char addr)
68 if ((addr & 1) == 0) {
69 /* is device writable? */
70 if (!iicbus_start(dev, (u_char)addr, 0)) {
75 /* is device readable? */
76 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count))
85 * We add all the devices which we know about.
86 * The generic attach routine will attach them if they are alive.
89 iicbus_attach(device_t dev)
94 struct iicbus_softc *sc = IICBUS_SOFTC(dev);
98 mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF);
99 iicbus_reset(dev, IIC_FASTEST, 0, NULL);
100 if (resource_int_value(device_get_name(dev),
101 device_get_unit(dev), "strict", &strict) == 0)
106 /* device probing is meaningless since the bus is supposed to be
107 * hot-plug. Moreover, some I2C chips do not appreciate random
108 * accesses like stop after start to fast, reads for less than
112 printf("Probing for devices on iicbus%d:", device_get_unit(dev));
114 /* probe any devices */
115 for (addr = 16; addr < 240; addr++) {
116 if (iic_probe_device(dev, (u_char)addr)) {
117 printf(" <%x>", addr);
122 bus_generic_probe(dev);
123 bus_enumerate_hinted_children(dev);
124 bus_generic_attach(dev);
129 iicbus_detach(device_t dev)
131 struct iicbus_softc *sc = IICBUS_SOFTC(dev);
133 iicbus_reset(dev, IIC_FASTEST, 0, NULL);
134 bus_generic_detach(dev);
135 mtx_destroy(&sc->lock);
140 iicbus_print_child(device_t dev, device_t child)
142 struct iicbus_ivar *devi = IICBUS_IVAR(child);
145 retval += bus_print_child_header(dev, child);
147 retval += printf(" at addr %#x", devi->addr);
148 retval += bus_print_child_footer(dev, child);
154 iicbus_probe_nomatch(device_t bus, device_t child)
156 struct iicbus_ivar *devi = IICBUS_IVAR(child);
158 device_printf(bus, "<unknown card>");
159 printf(" at addr %#x\n", devi->addr);
164 iicbus_child_location_str(device_t bus, device_t child, char *buf,
167 struct iicbus_ivar *devi = IICBUS_IVAR(child);
169 snprintf(buf, buflen, "addr=%#x", devi->addr);
174 iicbus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
182 iicbus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
184 struct iicbus_ivar *devi = IICBUS_IVAR(child);
189 case IICBUS_IVAR_ADDR:
190 *result = devi->addr;
197 iicbus_add_child(device_t dev, u_int order, const char *name, int unit)
200 struct iicbus_ivar *devi;
202 child = device_add_child_ordered(dev, order, name, unit);
205 devi = malloc(sizeof(struct iicbus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
207 device_delete_child(dev, child);
210 device_set_ivars(child, devi);
215 iicbus_hinted_child(device_t bus, const char *dname, int dunit)
218 struct iicbus_ivar *devi;
220 child = BUS_ADD_CHILD(bus, 0, dname, dunit);
221 devi = IICBUS_IVAR(child);
222 resource_int_value(dname, dunit, "addr", &devi->addr);
226 iicbus_generic_intr(device_t dev, int event, char *buf)
233 iicbus_null_callback(device_t dev, int index, caddr_t data)
240 iicbus_null_repeated_start(device_t dev, u_char addr)
243 return (IIC_ENOTSUPP);
246 static device_method_t iicbus_methods[] = {
247 /* device interface */
248 DEVMETHOD(device_probe, iicbus_probe),
249 DEVMETHOD(device_attach, iicbus_attach),
250 DEVMETHOD(device_detach, iicbus_detach),
253 DEVMETHOD(bus_add_child, iicbus_add_child),
254 DEVMETHOD(bus_print_child, iicbus_print_child),
255 DEVMETHOD(bus_probe_nomatch, iicbus_probe_nomatch),
256 DEVMETHOD(bus_read_ivar, iicbus_read_ivar),
257 DEVMETHOD(bus_child_pnpinfo_str, iicbus_child_pnpinfo_str),
258 DEVMETHOD(bus_child_location_str, iicbus_child_location_str),
259 DEVMETHOD(bus_hinted_child, iicbus_hinted_child),
261 /* iicbus interface */
262 DEVMETHOD(iicbus_transfer, iicbus_transfer),
267 driver_t iicbus_driver = {
270 sizeof(struct iicbus_softc),
273 devclass_t iicbus_devclass;
275 MODULE_VERSION(iicbus, IICBUS_MODVER);
276 DRIVER_MODULE(iicbus, iichb, iicbus_driver, iicbus_devclass, 0, 0);