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 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 /* 31 * Autoconfiguration and support routines for the Philips serial I2C bus 32 */ 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/kernel.h> 37 #include <sys/module.h> 38 #include <sys/bus.h> 39 40 41 #include <dev/iicbus/iiconf.h> 42 #include <dev/iicbus/iicbus.h> 43 44 #include "iicbus_if.h" 45 46 #define DEVTOIICBUS(dev) ((struct iicbus_device*)device_get_ivars(dev)) 47 48 devclass_t iicbus_devclass; 49 50 /* See comments below for why auto-scanning is a bad idea. */ 51 #define SCAN_IICBUS 0 52 53 /* 54 * Device methods 55 */ 56 static int iicbus_probe(device_t); 57 static int iicbus_attach(device_t); 58 static int iicbus_detach(device_t); 59 static int iicbus_add_child(device_t dev, int order, const char *name, int unit); 60 61 static device_method_t iicbus_methods[] = { 62 /* device interface */ 63 DEVMETHOD(device_probe, iicbus_probe), 64 DEVMETHOD(device_attach, iicbus_attach), 65 DEVMETHOD(device_detach, iicbus_detach), 66 67 /* bus interface */ 68 DEVMETHOD(bus_add_child, iicbus_add_child), 69 DEVMETHOD(bus_driver_added, bus_generic_driver_added), 70 DEVMETHOD(bus_print_child, bus_generic_print_child), 71 72 DEVMETHOD(iicbus_transfer, iicbus_transfer_gen), 73 74 { 0, 0 } 75 }; 76 77 driver_t iicbus_driver = { 78 "iicbus", 79 iicbus_methods, 80 sizeof(struct iicbus_softc), 81 }; 82 83 static int 84 iicbus_probe(device_t dev) 85 { 86 87 device_set_desc(dev, "Philips I2C bus"); 88 return (0); 89 } 90 91 #if SCAN_IICBUS 92 static int 93 iic_probe_device(device_t dev, u_char addr) 94 { 95 int count; 96 char byte; 97 98 if ((addr & 1) == 0) { 99 /* is device writable? */ 100 if (!iicbus_start(dev, (u_char)addr, 0)) { 101 iicbus_stop(dev); 102 return (1); 103 } 104 } else { 105 /* is device readable? */ 106 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count)) 107 return (1); 108 } 109 110 return (0); 111 } 112 #endif 113 114 /* 115 * We add all the devices which we know about. 116 * The generic attach routine will attach them if they are alive. 117 */ 118 static int 119 iicbus_attach(device_t dev) 120 { 121 #if SCAN_IICBUS 122 unsigned char addr; 123 #endif 124 125 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 126 127 /* device probing is meaningless since the bus is supposed to be 128 * hot-plug. Moreover, some I2C chips do not appreciate random 129 * accesses like stop after start to fast, reads for less than 130 * x bytes... 131 */ 132 #if SCAN_IICBUS 133 printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 134 135 /* probe any devices */ 136 for (addr = 16; addr < 240; addr++) { 137 if (iic_probe_device(dev, (u_char)addr)) { 138 printf(" <%x>", addr); 139 } 140 } 141 printf("\n"); 142 #endif 143 144 device_add_child(dev, "ic", -1); 145 device_add_child(dev, "iicsmb", -1); 146 device_add_child(dev, "ds1672", -1); 147 device_add_child(dev, "ad7418", -1); 148 #if 0 149 /* attach any known device */ 150 device_add_child(dev, "iic", -1); 151 #endif 152 bus_generic_attach(dev); 153 return (0); 154 } 155 156 static int 157 iicbus_detach(device_t dev) 158 { 159 160 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 161 bus_generic_detach(dev); 162 return (0); 163 } 164 165 static int 166 iicbus_add_child(device_t dev, int order, const char *name, int unit) 167 { 168 169 device_add_child_ordered(dev, order, name, unit); 170 bus_generic_attach(dev); 171 return (0); 172 } 173 174 int 175 iicbus_generic_intr(device_t dev, int event, char *buf) 176 { 177 178 return (0); 179 } 180 181 int 182 iicbus_null_callback(device_t dev, int index, caddr_t data) 183 { 184 185 return (0); 186 } 187 188 int 189 iicbus_null_repeated_start(device_t dev, u_char addr) 190 { 191 192 return (IIC_ENOTSUPP); 193 } 194 195 DRIVER_MODULE(iicbus, envctrl, iicbus_driver, iicbus_devclass, 0, 0); 196 DRIVER_MODULE(iicbus, iicbb, iicbus_driver, iicbus_devclass, 0, 0); 197 MODULE_VERSION(iicbus, IICBUS_MODVER); 198