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: iicbus.c,v 1.1.1.1 1998/09/03 20:51:50 nsouch Exp $ 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 #include <machine/clock.h> 41 42 #include <dev/iicbus/iiconf.h> 43 #include <dev/iicbus/iicbus.h> 44 45 #include "iicbus_if.h" 46 47 #define DEVTOIICBUS(dev) ((struct iicbus_device*)device_get_ivars(dev)) 48 49 /* 50 * structure used to attach devices to the I2C bus 51 */ 52 struct iicbus_device { 53 const char *iicd_name; /* device name */ 54 int iicd_class; /* driver or slave device class */ 55 const char *iicd_desc; /* device descriptor */ 56 u_char iicd_addr; /* address of the device */ 57 int iicd_waitack; /* wait for ack timeout or delay */ 58 int iicd_alive; /* 1 if device found */ 59 }; 60 61 /* 62 * Common I2C addresses 63 */ 64 #define I2C_GENERAL_CALL 0x0 65 #define PCF_MASTER_ADDRESS 0xaa 66 #define FIRST_SLAVE_ADDR 0x2 67 68 #define MAXSLAVE 256 69 70 #define IICBUS_UNKNOWN_CLASS 0 71 #define IICBUS_DEVICE_CLASS 1 72 #define IICBUS_DRIVER_CLASS 2 73 74 /* 75 * list of known devices 76 */ 77 struct iicbus_device iicbus_children[] = { 78 { "iicsmb", IICBUS_DRIVER_CLASS, "I2C to SMB bridge" }, 79 { "iic", IICBUS_DEVICE_CLASS, "PCF8574 I2C to 8 bits parallel i/o", 64}, 80 { "iic", IICBUS_DEVICE_CLASS, "PCF8584 as slave", PCF_MASTER_ADDRESS }, 81 { "ic", IICBUS_DEVICE_CLASS, "network interface", PCF_MASTER_ADDRESS }, 82 #if 0 83 { "iic", IICBUS_DRIVER_CLASS, "General Call", I2C_GENERAL_CALL }, 84 #endif 85 { NULL, 0 } 86 }; 87 88 static devclass_t iicbus_devclass; 89 90 /* 91 * Device methods 92 */ 93 static int iicbus_probe(device_t); 94 static int iicbus_attach(device_t); 95 static void iicbus_print_child(device_t, device_t); 96 static int iicbus_read_ivar(device_t , device_t, int, u_long *); 97 static int iicbus_write_ivar(device_t , device_t, int, u_long); 98 99 static device_method_t iicbus_methods[] = { 100 /* device interface */ 101 DEVMETHOD(device_probe, iicbus_probe), 102 DEVMETHOD(device_attach, iicbus_attach), 103 DEVMETHOD(device_detach, bus_generic_detach), 104 DEVMETHOD(device_shutdown, bus_generic_shutdown), 105 106 /* bus interface */ 107 DEVMETHOD(bus_print_child, iicbus_print_child), 108 DEVMETHOD(bus_read_ivar, iicbus_read_ivar), 109 DEVMETHOD(bus_write_ivar, iicbus_write_ivar), 110 DEVMETHOD(bus_create_intr, bus_generic_create_intr), 111 DEVMETHOD(bus_connect_intr, bus_generic_connect_intr), 112 113 { 0, 0 } 114 }; 115 116 static driver_t iicbus_driver = { 117 "iicbus", 118 iicbus_methods, 119 DRIVER_TYPE_MISC, 120 sizeof(struct iicbus_softc), 121 }; 122 123 static int 124 iicbus_probe(device_t dev) 125 { 126 /* always present if probed */ 127 return (0); 128 } 129 130 #define MAXADDR 256 131 static int iicdev_found[MAXADDR]; 132 133 static int 134 iic_probe_device(device_t dev, u_char addr) 135 { 136 int count; 137 char byte; 138 139 if ((addr & 1) == 0) { 140 /* is device writable? */ 141 if (!iicbus_start(dev, (u_char)addr, 0)) { 142 iicbus_stop(dev); 143 return (1); 144 } 145 } else { 146 /* is device readable? */ 147 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count)) 148 return (1); 149 } 150 151 return (0); 152 } 153 154 /* 155 * We add all the devices which we know about. 156 * The generic attach routine will attach them if they are alive. 157 */ 158 static int 159 iicbus_attach(device_t dev) 160 { 161 struct iicbus_softc *sc = device_get_softc(dev); 162 struct iicbus_device *iicdev; 163 device_t child; 164 int addr, count; 165 char byte; 166 167 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 168 169 printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 170 171 /* probe any devices */ 172 for (addr = FIRST_SLAVE_ADDR; addr < MAXADDR; addr++) { 173 if (iic_probe_device(dev, (u_char)addr)) { 174 printf(" <%x>", addr); 175 } 176 } 177 printf("\n"); 178 179 /* attach known devices */ 180 for (iicdev = iicbus_children; iicdev->iicd_name; iicdev++) { 181 /* probe devices, not drivers */ 182 switch (iicdev->iicd_class) { 183 case IICBUS_DEVICE_CLASS: 184 if (iic_probe_device(dev, iicdev->iicd_addr)) 185 iicdev->iicd_alive = 1; 186 break; 187 188 case IICBUS_DRIVER_CLASS: 189 iicdev->iicd_alive = 1; 190 break; 191 192 default: 193 panic("%s: unknown class!", __FUNCTION__); 194 } 195 196 if (iicdev->iicd_alive) { 197 child = device_add_child(dev, iicdev->iicd_name, 198 -1, iicdev); 199 device_set_desc(child, iicdev->iicd_desc); 200 } 201 } 202 bus_generic_attach(dev); 203 204 return (0); 205 } 206 207 int 208 iicbus_generic_intr(device_t dev, int event, char *buf) 209 { 210 return (0); 211 } 212 213 int 214 iicbus_null_callback(device_t dev, int index, caddr_t data) 215 { 216 return (0); 217 } 218 219 int 220 iicbus_null_repeated_start(device_t dev, u_char addr) 221 { 222 return (IIC_ENOTSUPP); 223 } 224 225 static void 226 iicbus_print_child(device_t bus, device_t dev) 227 { 228 struct iicbus_device* iicdev = DEVTOIICBUS(dev); 229 230 switch (iicdev->iicd_class) { 231 case IICBUS_DEVICE_CLASS: 232 printf(" on %s%d addr 0x%x", device_get_name(bus), 233 device_get_unit(bus), iicdev->iicd_addr); 234 break; 235 236 case IICBUS_DRIVER_CLASS: 237 printf(" on %s%d", device_get_name(bus), 238 device_get_unit(bus)); 239 break; 240 241 default: 242 panic("%s: unknown class!", __FUNCTION__); 243 } 244 245 return; 246 } 247 248 static int 249 iicbus_read_ivar(device_t bus, device_t dev, int index, u_long* result) 250 { 251 struct iicbus_device* iicdev = DEVTOIICBUS(dev); 252 253 switch (index) { 254 case IICBUS_IVAR_ADDR: 255 *result = (u_long)iicdev->iicd_addr; 256 break; 257 258 default: 259 return (ENOENT); 260 } 261 262 return (0); 263 } 264 265 static int 266 iicbus_write_ivar(device_t bus, device_t dev, int index, u_long val) 267 { 268 struct iicbus_device* iicdev = DEVTOIICBUS(dev); 269 270 switch (index) { 271 default: 272 return (ENOENT); 273 } 274 275 return (0); 276 } 277 278 DRIVER_MODULE(iicbus, pcf, iicbus_driver, iicbus_devclass, 0, 0); 279 DRIVER_MODULE(iicbus, iicbb, iicbus_driver, iicbus_devclass, 0, 0); 280 DRIVER_MODULE(iicbus, bti2c, iicbus_driver, iicbus_devclass, 0, 0); 281