1 /*- 2 * Copyright (c) 1998 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 1.9 1999/12/03 08:41:08 mdodd Exp $ 27 * $DragonFly: src/sys/bus/smbus/smbconf.c,v 1.3 2003/07/19 21:14:28 dillon Exp $ 28 * 29 */ 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/kernel.h> 33 #include <sys/malloc.h> 34 #include <sys/module.h> 35 #include <sys/bus.h> 36 37 #include <dev/smbus/smbconf.h> 38 #include <dev/smbus/smbus.h> 39 #include "smbus_if.h" 40 41 /* 42 * smbus_intr() 43 */ 44 void 45 smbus_intr(device_t bus, u_char devaddr, char low, char high, int error) 46 { 47 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus); 48 49 /* call owner's intr routine */ 50 if (sc->owner) 51 SMBUS_INTR(sc->owner, devaddr, low, high, error); 52 53 return; 54 } 55 56 /* 57 * smbus_error() 58 * 59 * Converts an smbus error to a unix error. 60 */ 61 int 62 smbus_error(int smb_error) 63 { 64 int error = 0; 65 66 if (smb_error == SMB_ENOERR) 67 return (0); 68 69 if (smb_error & (SMB_ENOTSUPP)) { 70 error = ENODEV; 71 } else if (smb_error & (SMB_ENOACK)) { 72 error = ENXIO; 73 } else if (smb_error & (SMB_ETIMEOUT)) { 74 error = EWOULDBLOCK; 75 } else if (smb_error & (SMB_EBUSY)) { 76 error = EBUSY; 77 } else { 78 error = EINVAL; 79 } 80 81 return (error); 82 } 83 84 /* 85 * smbus_alloc_bus() 86 * 87 * Allocate a new bus connected to the given parent device 88 */ 89 device_t 90 smbus_alloc_bus(device_t parent) 91 { 92 device_t child; 93 94 /* add the bus to the parent */ 95 child = device_add_child(parent, "smbus", -1); 96 97 return (child); 98 } 99 100 static int 101 smbus_poll(struct smbus_softc *sc, int how) 102 { 103 int error; 104 105 switch (how) { 106 case (SMB_WAIT | SMB_INTR): 107 error = tsleep(sc, PCATCH, "smbreq", 0); 108 break; 109 110 case (SMB_WAIT | SMB_NOINTR): 111 error = tsleep(sc, 0, "smbreq", 0); 112 break; 113 114 default: 115 return (EWOULDBLOCK); 116 break; 117 } 118 119 return (error); 120 } 121 122 /* 123 * smbus_request_bus() 124 * 125 * Allocate the device to perform transfers. 126 * 127 * how : SMB_WAIT or SMB_DONTWAIT 128 */ 129 int 130 smbus_request_bus(device_t bus, device_t dev, int how) 131 { 132 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus); 133 int s, error = 0; 134 135 /* first, ask the underlying layers if the request is ok */ 136 do { 137 error = SMBUS_CALLBACK(device_get_parent(bus), 138 SMB_REQUEST_BUS, (caddr_t)&how); 139 if (error) 140 error = smbus_poll(sc, how); 141 } while (error == EWOULDBLOCK); 142 143 while (!error) { 144 s = splhigh(); 145 if (sc->owner && sc->owner != dev) { 146 splx(s); 147 148 error = smbus_poll(sc, how); 149 } else { 150 sc->owner = dev; 151 152 splx(s); 153 return (0); 154 } 155 156 /* free any allocated resource */ 157 if (error) 158 SMBUS_CALLBACK(device_get_parent(bus), SMB_RELEASE_BUS, 159 (caddr_t)&how); 160 } 161 162 return (error); 163 } 164 165 /* 166 * smbus_release_bus() 167 * 168 * Release the device allocated with smbus_request_dev() 169 */ 170 int 171 smbus_release_bus(device_t bus, device_t dev) 172 { 173 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus); 174 int s, error; 175 176 /* first, ask the underlying layers if the release is ok */ 177 error = SMBUS_CALLBACK(device_get_parent(bus), SMB_RELEASE_BUS, NULL); 178 179 if (error) 180 return (error); 181 182 s = splhigh(); 183 if (sc->owner != dev) { 184 splx(s); 185 return (EACCES); 186 } 187 188 sc->owner = 0; 189 splx(s); 190 191 /* wakeup waiting processes */ 192 wakeup(sc); 193 194 return (0); 195 } 196 197 /* 198 * smbus_get_addr() 199 * 200 * Get the I2C 7 bits address of the device 201 */ 202 u_char 203 smbus_get_addr(device_t dev) 204 { 205 uintptr_t addr; 206 device_t parent = device_get_parent(dev); 207 208 BUS_READ_IVAR(parent, dev, SMBUS_IVAR_ADDR, &addr); 209 210 return ((u_char)addr); 211 } 212