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 * $FreeBSD$ 27 * 28 */ 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 /* 49 * structure used to attach devices to the I2C bus 50 */ 51 struct iicbus_device { 52 const char *iicd_name; /* device name */ 53 int iicd_class; /* driver or slave device class */ 54 const char *iicd_desc; /* device descriptor */ 55 u_char iicd_addr; /* address of the device */ 56 int iicd_waitack; /* wait for ack timeout or delay */ 57 int iicd_alive; /* 1 if device found */ 58 }; 59 60 /* 61 * Common I2C addresses 62 */ 63 #define I2C_GENERAL_CALL 0x0 64 #define PCF_MASTER_ADDRESS 0xaa 65 #define FIRST_SLAVE_ADDR 0x2 66 67 #define LAST_SLAVE_ADDR 255 68 69 #define IICBUS_UNKNOWN_CLASS 0 70 #define IICBUS_DEVICE_CLASS 1 71 #define IICBUS_DRIVER_CLASS 2 72 73 /* 74 * list of known devices 75 * 76 * XXX only one smb driver should exist for each I2C interface 77 */ 78 static struct iicbus_device iicbus_children[] = { 79 { "iicsmb", IICBUS_DRIVER_CLASS, "I2C to SMB bridge" }, 80 { "iic", IICBUS_DRIVER_CLASS, "I2C general purpose I/O" }, 81 #if 0 82 { "ic", IICBUS_DEVICE_CLASS, "network interface", PCF_MASTER_ADDRESS }, 83 #endif 84 { NULL, 0 } 85 }; 86 87 static devclass_t iicbus_devclass; 88 89 /* 90 * Device methods 91 */ 92 static int iicbus_probe(device_t); 93 static int iicbus_attach(device_t); 94 static int iicbus_print_child(device_t, device_t); 95 static int iicbus_read_ivar(device_t , device_t, int, u_long *); 96 static int iicbus_write_ivar(device_t , device_t, int, u_long); 97 98 static device_method_t iicbus_methods[] = { 99 /* device interface */ 100 DEVMETHOD(device_probe, iicbus_probe), 101 DEVMETHOD(device_attach, iicbus_attach), 102 DEVMETHOD(device_detach, bus_generic_detach), 103 DEVMETHOD(device_shutdown, bus_generic_shutdown), 104 105 /* bus interface */ 106 DEVMETHOD(bus_print_child, iicbus_print_child), 107 DEVMETHOD(bus_read_ivar, iicbus_read_ivar), 108 DEVMETHOD(bus_write_ivar, iicbus_write_ivar), 109 110 { 0, 0 } 111 }; 112 113 static driver_t iicbus_driver = { 114 "iicbus", 115 iicbus_methods, 116 sizeof(struct iicbus_softc), 117 }; 118 119 static int 120 iicbus_probe(device_t dev) 121 { 122 device_set_desc(dev, "Philips I2C bus"); 123 124 return (0); 125 } 126 127 #if 0 128 static int 129 iic_probe_device(device_t dev, u_char addr) 130 { 131 int count; 132 char byte; 133 134 if ((addr & 1) == 0) { 135 /* is device writable? */ 136 if (!iicbus_start(dev, (u_char)addr, 0)) { 137 iicbus_stop(dev); 138 return (1); 139 } 140 } else { 141 /* is device readable? */ 142 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count)) 143 return (1); 144 } 145 146 return (0); 147 } 148 #endif 149 150 /* 151 * We add all the devices which we know about. 152 * The generic attach routine will attach them if they are alive. 153 */ 154 static int 155 iicbus_attach(device_t dev) 156 { 157 struct iicbus_device *iicdev; 158 device_t child; 159 160 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 161 162 /* device probing is meaningless since the bus is supposed to be 163 * hot-plug. Moreover, some I2C chips do not appreciate random 164 * accesses like stop after start to fast, reads for less than 165 * x bytes... 166 */ 167 #if 0 168 printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 169 170 /* probe any devices */ 171 for (addr = FIRST_SLAVE_ADDR; addr <= LAST_SLAVE_ADDR; addr++) { 172 if (iic_probe_device(dev, (u_char)addr)) { 173 printf(" <%x>", addr); 174 } 175 } 176 printf("\n"); 177 #endif 178 179 /* attach known devices */ 180 for (iicdev = iicbus_children; iicdev->iicd_name; iicdev++) { 181 switch (iicdev->iicd_class) { 182 case IICBUS_DEVICE_CLASS: 183 /* check if the devclass exists */ 184 if (devclass_find(iicdev->iicd_name)) 185 iicdev->iicd_alive = 1; 186 else if (bootverbose) 187 printf("iicbus: %s devclass not found\n", 188 iicdev->iicd_name); 189 break; 190 191 case IICBUS_DRIVER_CLASS: 192 /* check if the devclass exists */ 193 if (devclass_find(iicdev->iicd_name)) 194 iicdev->iicd_alive = 1; 195 else if (bootverbose) 196 printf("iicbus: %s devclass not found\n", 197 iicdev->iicd_name); 198 break; 199 200 default: 201 panic("%s: unknown class!", __FUNCTION__); 202 } 203 204 if (iicdev->iicd_alive) { 205 child = device_add_child(dev, iicdev->iicd_name, -1); 206 device_set_ivars(child, iicdev); 207 device_set_desc(child, iicdev->iicd_desc); 208 } 209 } 210 bus_generic_attach(dev); 211 212 return (0); 213 } 214 215 int 216 iicbus_generic_intr(device_t dev, int event, char *buf) 217 { 218 return (0); 219 } 220 221 int 222 iicbus_null_callback(device_t dev, int index, caddr_t data) 223 { 224 return (0); 225 } 226 227 int 228 iicbus_null_repeated_start(device_t dev, u_char addr) 229 { 230 return (IIC_ENOTSUPP); 231 } 232 233 static int 234 iicbus_print_child(device_t bus, device_t dev) 235 { 236 struct iicbus_device* iicdev = DEVTOIICBUS(dev); 237 int retval = 0; 238 239 retval += bus_print_child_header(bus, dev); 240 241 switch (iicdev->iicd_class) { 242 case IICBUS_DEVICE_CLASS: 243 retval += printf(" on %s addr 0x%x\n", 244 device_get_nameunit(bus), iicdev->iicd_addr); 245 break; 246 247 case IICBUS_DRIVER_CLASS: 248 retval += bus_print_child_footer(bus, dev); 249 break; 250 251 default: 252 panic("%s: unknown class!", __FUNCTION__); 253 } 254 255 return (retval); 256 } 257 258 static int 259 iicbus_read_ivar(device_t bus, device_t dev, int index, u_long* result) 260 { 261 struct iicbus_device* iicdev = DEVTOIICBUS(dev); 262 263 switch (index) { 264 case IICBUS_IVAR_ADDR: 265 *result = (u_long)iicdev->iicd_addr; 266 break; 267 268 default: 269 return (ENOENT); 270 } 271 272 return (0); 273 } 274 275 static int 276 iicbus_write_ivar(device_t bus, device_t dev, int index, u_long val) 277 { 278 switch (index) { 279 default: 280 return (ENOENT); 281 } 282 283 return (0); 284 } 285 286 DRIVER_MODULE(iicbus, pcf, iicbus_driver, iicbus_devclass, 0, 0); 287 DRIVER_MODULE(iicbus, iicbb, iicbus_driver, iicbus_devclass, 0, 0); 288 DRIVER_MODULE(iicbus, bti2c, iicbus_driver, iicbus_devclass, 0, 0); 289