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("$FreeBSD$"); 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 */ 43 void 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 return; 53 } 54 55 /* 56 * smbus_error() 57 * 58 * Converts an smbus error to a unix error. 59 */ 60 int 61 smbus_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 83 static int 84 smbus_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 */ 112 int 113 smbus_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 */ 153 int 154 smbus_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 } 179