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 * $Id: smbconf.c,v 1.3 1998/11/22 22:01:42 nsouch Exp $ 27 * 28 */ 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/kernel.h> 32 #include <sys/malloc.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_alloc_bus() 57 * 58 * Allocate a new bus connected to the given parent device 59 */ 60 device_t 61 smbus_alloc_bus(device_t parent) 62 { 63 device_t child; 64 65 /* add the bus to the parent */ 66 child = device_add_child(parent, "smbus", -1, NULL); 67 68 return (child); 69 } 70 71 static int 72 smbus_poll(struct smbus_softc *sc, int how) 73 { 74 int error; 75 76 switch (how) { 77 case (SMB_WAIT | SMB_INTR): 78 error = tsleep(sc, SMBPRI|PCATCH, "smbreq", 0); 79 break; 80 81 case (SMB_WAIT | SMB_NOINTR): 82 error = tsleep(sc, SMBPRI, "smbreq", 0); 83 break; 84 85 default: 86 return (EWOULDBLOCK); 87 break; 88 } 89 90 return (error); 91 } 92 93 /* 94 * smbus_request_bus() 95 * 96 * Allocate the device to perform transfers. 97 * 98 * how : SMB_WAIT or SMB_DONTWAIT 99 */ 100 int 101 smbus_request_bus(device_t bus, device_t dev, int how) 102 { 103 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus); 104 int s, error = 0; 105 106 /* first, ask the underlying layers if the request is ok */ 107 do { 108 error = SMBUS_CALLBACK(device_get_parent(bus), 109 SMB_REQUEST_BUS, (caddr_t)&how); 110 if (error) 111 error = smbus_poll(sc, how); 112 } while (error); 113 114 while (!error) { 115 s = splhigh(); 116 if (sc->owner) { 117 splx(s); 118 119 error = smbus_poll(sc, how); 120 } else { 121 sc->owner = dev; 122 123 splx(s); 124 return (0); 125 } 126 } 127 128 return (error); 129 } 130 131 /* 132 * smbus_release_bus() 133 * 134 * Release the device allocated with smbus_request_dev() 135 */ 136 int 137 smbus_release_bus(device_t bus, device_t dev) 138 { 139 struct smbus_softc *sc = (struct smbus_softc *)device_get_softc(bus); 140 int s, error; 141 142 /* first, ask the underlying layers if the release is ok */ 143 error = SMBUS_CALLBACK(device_get_parent(bus), SMB_RELEASE_BUS, NULL); 144 145 if (error) 146 return (error); 147 148 s = splhigh(); 149 if (sc->owner != dev) { 150 splx(s); 151 return (EACCES); 152 } 153 154 sc->owner = 0; 155 splx(s); 156 157 /* wakeup waiting processes */ 158 wakeup(sc); 159 160 return (0); 161 } 162 163 /* 164 * smbus_get_addr() 165 * 166 * Get the I2C 7 bits address of the device 167 */ 168 u_char 169 smbus_get_addr(device_t dev) 170 { 171 uintptr_t addr; 172 device_t parent = device_get_parent(dev); 173 174 BUS_READ_IVAR(parent, dev, SMBUS_IVAR_ADDR, &addr); 175 176 return ((u_char)addr); 177 } 178