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 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 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 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 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 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