1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1998, 2001 Nicolas Souchu
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 AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, 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 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD$");
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/lock.h>
36#include <sys/malloc.h>
37#include <sys/module.h>
38#include <sys/mutex.h>
39#include <sys/bus.h>
40
41#include <dev/smbus/smbconf.h>
42#include <dev/smbus/smbus.h>
43
44#include "smbus_if.h"
45#include "bus_if.h"
46
47struct smbus_ivar
48{
49	uint8_t	addr;
50};
51
52/*
53 * Autoconfiguration and support routines for System Management bus
54 */
55
56static int
57smbus_probe(device_t dev)
58{
59
60	device_set_desc(dev, "System Management Bus");
61
62	return (0);
63}
64
65static int
66smbus_attach(device_t dev)
67{
68	struct smbus_softc *sc = device_get_softc(dev);
69
70	mtx_init(&sc->lock, device_get_nameunit(dev), "smbus", MTX_DEF);
71	bus_generic_probe(dev);
72	bus_enumerate_hinted_children(dev);
73	bus_generic_attach(dev);
74
75	return (0);
76}
77
78static int
79smbus_detach(device_t dev)
80{
81	struct smbus_softc *sc = device_get_softc(dev);
82	int error;
83
84	error = bus_generic_detach(dev);
85	if (error)
86		return (error);
87	device_delete_children(dev);
88	mtx_destroy(&sc->lock);
89
90	return (0);
91}
92
93void
94smbus_generic_intr(device_t dev, u_char devaddr, char low, char high, int err)
95{
96}
97
98static device_t
99smbus_add_child(device_t dev, u_int order, const char *name, int unit)
100{
101	struct smbus_ivar *devi;
102	device_t child;
103
104	child = device_add_child_ordered(dev, order, name, unit);
105	if (child == NULL)
106		return (child);
107	devi = malloc(sizeof(struct smbus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
108	if (devi == NULL) {
109		device_delete_child(dev, child);
110		return (NULL);
111	}
112	device_set_ivars(child, devi);
113	return (child);
114}
115
116static void
117smbus_hinted_child(device_t bus, const char *dname, int dunit)
118{
119	struct smbus_ivar *devi;
120	device_t child;
121	int addr;
122
123	addr = 0;
124	resource_int_value(dname, dunit, "addr", &addr);
125	if (addr > UINT8_MAX) {
126		device_printf(bus, "ignored incorrect slave address hint 0x%x"
127		    " for %s%d\n", addr, dname, dunit);
128		return;
129	}
130	child = BUS_ADD_CHILD(bus, SMBUS_ORDER_HINTED, dname, dunit);
131	if (child == NULL)
132		return;
133	devi = device_get_ivars(child);
134	devi->addr = addr;
135}
136
137
138static int
139smbus_child_location_str(device_t parent, device_t child, char *buf,
140    size_t buflen)
141{
142	struct smbus_ivar *devi;
143
144	devi = device_get_ivars(child);
145	if (devi->addr != 0)
146		snprintf(buf, buflen, "addr=0x%x", devi->addr);
147	else if (buflen)
148		buf[0] = 0;
149	return (0);
150}
151
152static int
153smbus_print_child(device_t parent, device_t child)
154{
155	struct smbus_ivar *devi;
156	int retval;
157
158	devi = device_get_ivars(child);
159	retval = bus_print_child_header(parent, child);
160	if (devi->addr != 0)
161		retval += printf(" at addr 0x%x", devi->addr);
162	retval += bus_print_child_footer(parent, child);
163
164	return (retval);
165}
166
167static int
168smbus_read_ivar(device_t parent, device_t child, int which, uintptr_t *result)
169{
170	struct smbus_ivar *devi;
171
172	devi = device_get_ivars(child);
173	switch (which) {
174	case SMBUS_IVAR_ADDR:
175		if (devi->addr != 0)
176			*result = devi->addr;
177		else
178			*result = -1;
179		break;
180	default:
181		return (ENOENT);
182	}
183	return (0);
184}
185
186static int
187smbus_write_ivar(device_t parent, device_t child, int which, uintptr_t value)
188{
189	struct smbus_ivar *devi;
190
191	devi = device_get_ivars(child);
192	switch (which) {
193	case SMBUS_IVAR_ADDR:
194		/* Allow to set but no change the slave address. */
195		if (devi->addr != 0)
196			return (EINVAL);
197		devi->addr = value;
198		break;
199	default:
200		return (ENOENT);
201	}
202	return (0);
203}
204
205static void
206smbus_probe_nomatch(device_t bus, device_t child)
207{
208	struct smbus_ivar *devi = device_get_ivars(child);
209
210	/*
211	 * Ignore (self-identified) devices without a slave address set.
212	 * For example, smb(4).
213	 */
214	if (devi->addr != 0)
215		device_printf(bus, "<unknown device> at addr %#x\n",
216		    devi->addr);
217}
218
219/*
220 * Device methods
221 */
222static device_method_t smbus_methods[] = {
223        /* device interface */
224        DEVMETHOD(device_probe,         smbus_probe),
225        DEVMETHOD(device_attach,        smbus_attach),
226        DEVMETHOD(device_detach,        smbus_detach),
227
228	/* bus interface */
229	DEVMETHOD(bus_add_child,	smbus_add_child),
230	DEVMETHOD(bus_hinted_child,	smbus_hinted_child),
231	DEVMETHOD(bus_probe_nomatch,	smbus_probe_nomatch),
232	DEVMETHOD(bus_child_location_str, smbus_child_location_str),
233	DEVMETHOD(bus_print_child,	smbus_print_child),
234	DEVMETHOD(bus_read_ivar,	smbus_read_ivar),
235	DEVMETHOD(bus_write_ivar,	smbus_write_ivar),
236
237	DEVMETHOD_END
238};
239
240driver_t smbus_driver = {
241        "smbus",
242        smbus_methods,
243        sizeof(struct smbus_softc),
244};
245
246devclass_t smbus_devclass;
247
248MODULE_VERSION(smbus, SMBUS_MODVER);
249