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 *
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: head/sys/dev/smbus/smbconf.c 119419 2003-08-24 18:03:45Z obrien $");
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/module.h>
34#include <sys/bus.h>
35
36#include <dev/smbus/smbconf.h>
37#include <dev/smbus/smbus.h>
38#include "smbus_if.h"
39
40/*
41 * smbus_intr()
42 */
43void
44smbus_intr(device_t bus, u_char devaddr, char low, char high, int error)
45{
46 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus);
47
48 /* call owner's intr routine */
49 if (sc->owner)
50 SMBUS_INTR(sc->owner, devaddr, low, high, error);
51
52 return;
53}
54
55/*
56 * smbus_error()
57 *
58 * Converts an smbus error to a unix error.
59 */
60int
61smbus_error(int smb_error)
62{
63 int error = 0;
64
65 if (smb_error == SMB_ENOERR)
66 return (0);
67
68 if (smb_error & (SMB_ENOTSUPP)) {
69 error = ENODEV;
70 } else if (smb_error & (SMB_ENOACK)) {
71 error = ENXIO;
72 } else if (smb_error & (SMB_ETIMEOUT)) {
73 error = EWOULDBLOCK;
74 } else if (smb_error & (SMB_EBUSY)) {
75 error = EBUSY;
76 } else {
77 error = EINVAL;
78 }
79
80 return (error);
81}
82
83static int
84smbus_poll(struct smbus_softc *sc, int how)
85{
86 int error;
87
88 switch (how) {
89 case (SMB_WAIT | SMB_INTR):
90 error = tsleep(sc, SMBPRI|PCATCH, "smbreq", 0);
91 break;
92
93 case (SMB_WAIT | SMB_NOINTR):
94 error = tsleep(sc, SMBPRI, "smbreq", 0);
95 break;
96
97 default:
98 return (EWOULDBLOCK);
99 break;
100 }
101
102 return (error);
103}
104
105/*
106 * smbus_request_bus()
107 *
108 * Allocate the device to perform transfers.
109 *
110 * how : SMB_WAIT or SMB_DONTWAIT
111 */
112int
113smbus_request_bus(device_t bus, device_t dev, int how)
114{
115 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus);
116 int s, error = 0;
117
118 /* first, ask the underlying layers if the request is ok */
119 do {
120 error = SMBUS_CALLBACK(device_get_parent(bus),
121 SMB_REQUEST_BUS, (caddr_t)&how);
122 if (error)
123 error = smbus_poll(sc, how);
124 } while (error == EWOULDBLOCK);
125
126 while (!error) {
127 s = splhigh();
128 if (sc->owner && sc->owner != dev) {
129 splx(s);
130
131 error = smbus_poll(sc, how);
132 } else {
133 sc->owner = dev;
134
135 splx(s);
136 return (0);
137 }
138
139 /* free any allocated resource */
140 if (error)
141 SMBUS_CALLBACK(device_get_parent(bus), SMB_RELEASE_BUS,
142 (caddr_t)&how);
143 }
144
145 return (error);
146}
147
148/*
149 * smbus_release_bus()
150 *
151 * Release the device allocated with smbus_request_dev()
152 */
153int
154smbus_release_bus(device_t bus, device_t dev)
155{
156 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus);
157 int s, error;
158
159 /* first, ask the underlying layers if the release is ok */
160 error = SMBUS_CALLBACK(device_get_parent(bus), SMB_RELEASE_BUS, NULL);
161
162 if (error)
163 return (error);
164
165 s = splhigh();
166 if (sc->owner != dev) {
167 splx(s);
168 return (EACCES);
169 }
170
171 sc->owner = 0;
172 splx(s);
173
174 /* wakeup waiting processes */
175 wakeup(sc);
176
177 return (0);
178}