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 * $FreeBSD: src/sys/dev/smbus/smbconf.c,v 1.13.10.1 2006/09/22 19:19:16 jhb Exp $
27 * $DragonFly: src/sys/bus/smbus/smbconf.c,v 1.5 2005/06/02 20:40:38 dillon Exp $
28 *
29 */
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/module.h>
33 #include <sys/bus.h>
34 #include <sys/thread2.h>
35
36 #include "smbconf.h"
37 #include "smbus.h"
38 #include "smbus_if.h"
39
40 /*
41 * smbus_intr()
42 */
43 void
smbus_intr(device_t bus,u_char devaddr,char low,char high,int error)44 smbus_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
53 /*
54 * smbus_error()
55 *
56 * Converts an smbus error to a unix error.
57 */
58 int
smbus_error(int smb_error)59 smbus_error(int smb_error)
60 {
61 int error = 0;
62
63 if (smb_error == SMB_ENOERR)
64 return (0);
65
66 if (smb_error & (SMB_ENOTSUPP))
67 error = ENODEV;
68 else if (smb_error & (SMB_ENOACK))
69 error = ENXIO;
70 else if (smb_error & (SMB_ETIMEOUT))
71 error = EWOULDBLOCK;
72 else if (smb_error & (SMB_EBUSY))
73 error = EBUSY;
74 else if (smb_error & (SMB_EABORT | SMB_EBUSERR | SMB_ECOLLI))
75 error = EIO;
76 else
77 error = EINVAL;
78
79 return (error);
80 }
81
82 static int
smbus_poll(struct smbus_softc * sc,int how)83 smbus_poll(struct smbus_softc *sc, int how)
84 {
85 int error;
86
87 switch (how) {
88 case (SMB_WAIT | SMB_INTR):
89 error = tsleep(sc, PCATCH, "smbreq", 0);
90 break;
91
92 case (SMB_WAIT | SMB_NOINTR):
93 error = tsleep(sc, 0, "smbreq", 0);
94 break;
95
96 default:
97 error = EWOULDBLOCK;
98 break;
99 }
100
101 return (error);
102 }
103
104 /*
105 * smbus_request_bus()
106 *
107 * Allocate the device to perform transfers.
108 *
109 * how : SMB_WAIT or SMB_DONTWAIT
110 */
111 int
smbus_request_bus(device_t bus,device_t dev,int how)112 smbus_request_bus(device_t bus, device_t dev, int how)
113 {
114 struct smbus_softc *sc = device_get_softc(bus);
115 device_t parent;
116 int error;
117
118 /* first, ask the underlying layers if the request is ok */
119 parent = device_get_parent(bus);
120 do {
121 error = SMBUS_CALLBACK(parent, SMB_REQUEST_BUS, &how);
122 if (error)
123 error = smbus_poll(sc, how);
124 } while (error == EWOULDBLOCK);
125
126 while (error == 0) {
127 crit_enter();
128 if (sc->owner && sc->owner != dev) {
129 crit_exit();
130 error = smbus_poll(sc, how);
131 if (error == EWOULDBLOCK)
132 error = 0;
133 } else {
134 sc->owner = dev;
135 crit_exit();
136 }
137 if (error == 0)
138 break;
139 /* free any allocated resource */
140 SMBUS_CALLBACK(parent, SMB_RELEASE_BUS, &how);
141 }
142
143 return (error);
144 }
145
146 /*
147 * smbus_release_bus()
148 *
149 * Release the device allocated with smbus_request_dev()
150 */
151 int
smbus_release_bus(device_t bus,device_t dev)152 smbus_release_bus(device_t bus, device_t dev)
153 {
154 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus);
155 device_t parent;
156 int error;
157
158 parent = device_get_parent(bus);
159 /* first, ask the underlying layers if the release is ok */
160 error = SMBUS_CALLBACK(parent, SMB_RELEASE_BUS, NULL);
161
162 if (error)
163 return (error);
164
165 crit_enter();
166 if (sc->owner == dev) {
167 sc->owner = NULL;
168
169 /* wakeup waiting processes */
170 wakeup(sc);
171 } else {
172 error = EACCES;
173 }
174 crit_exit();
175
176 /* wakeup waiting processes */
177 wakeup(sc);
178
179 return (error);
180 }
181