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 1.5 1998/11/22 22:01:42 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 LAST_SLAVE_ADDR 255 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), 110 111 { 0, 0 } 112 }; 113 114 static driver_t iicbus_driver = { 115 "iicbus", 116 iicbus_methods, 117 DRIVER_TYPE_MISC, 118 sizeof(struct iicbus_softc), 119 }; 120 121 static int 122 iicbus_probe(device_t dev) 123 { 124 /* always present if probed */ 125 return (0); 126 } 127 128 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 } 148 149 /* 150 * We add all the devices which we know about. 151 * The generic attach routine will attach them if they are alive. 152 */ 153 static int 154 iicbus_attach(device_t dev) 155 { 156 struct iicbus_device *iicdev; 157 device_t child; 158 int addr; 159 160 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 161 162 printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 163 164 /* probe any devices */ 165 for (addr = FIRST_SLAVE_ADDR; addr <= LAST_SLAVE_ADDR; addr++) { 166 if (iic_probe_device(dev, (u_char)addr)) { 167 printf(" <%x>", addr); 168 } 169 } 170 printf("\n"); 171 172 /* attach known devices */ 173 for (iicdev = iicbus_children; iicdev->iicd_name; iicdev++) { 174 switch (iicdev->iicd_class) { 175 case IICBUS_DEVICE_CLASS: 176 /* check if the devclass exists */ 177 if (devclass_find(iicdev->iicd_name) && 178 iic_probe_device(dev, iicdev->iicd_addr)) 179 iicdev->iicd_alive = 1; 180 break; 181 182 case IICBUS_DRIVER_CLASS: 183 /* check if the devclass exists */ 184 if (!devclass_find(iicdev->iicd_name)) 185 iicdev->iicd_alive = 1; 186 break; 187 188 default: 189 panic("%s: unknown class!", __FUNCTION__); 190 } 191 192 if (iicdev->iicd_alive) { 193 child = device_add_child(dev, iicdev->iicd_name, 194 -1, iicdev); 195 device_set_desc(child, iicdev->iicd_desc); 196 } 197 } 198 bus_generic_attach(dev); 199 200 return (0); 201 } 202 203 int 204 iicbus_generic_intr(device_t dev, int event, char *buf) 205 { 206 return (0); 207 } 208 209 int 210 iicbus_null_callback(device_t dev, int index, caddr_t data) 211 { 212 return (0); 213 } 214 215 int 216 iicbus_null_repeated_start(device_t dev, u_char addr) 217 { 218 return (IIC_ENOTSUPP); 219 } 220 221 static void 222 iicbus_print_child(device_t bus, device_t dev) 223 { 224 struct iicbus_device* iicdev = DEVTOIICBUS(dev); 225 226 switch (iicdev->iicd_class) { 227 case IICBUS_DEVICE_CLASS: 228 printf(" on %s%d addr 0x%x", device_get_name(bus), 229 device_get_unit(bus), iicdev->iicd_addr); 230 break; 231 232 case IICBUS_DRIVER_CLASS: 233 printf(" on %s%d", device_get_name(bus), 234 device_get_unit(bus)); 235 break; 236 237 default: 238 panic("%s: unknown class!", __FUNCTION__); 239 } 240 241 return; 242 } 243 244 static int 245 iicbus_read_ivar(device_t bus, device_t dev, int index, u_long* result) 246 { 247 struct iicbus_device* iicdev = DEVTOIICBUS(dev); 248 249 switch (index) { 250 case IICBUS_IVAR_ADDR: 251 *result = (u_long)iicdev->iicd_addr; 252 break; 253 254 default: 255 return (ENOENT); 256 } 257 258 return (0); 259 } 260 261 static int 262 iicbus_write_ivar(device_t bus, device_t dev, int index, u_long val) 263 { 264 switch (index) { 265 default: 266 return (ENOENT); 267 } 268 269 return (0); 270 } 271 272 DRIVER_MODULE(iicbus, pcf, iicbus_driver, iicbus_devclass, 0, 0); 273 DRIVER_MODULE(iicbus, iicbb, iicbus_driver, iicbus_devclass, 0, 0); 274 DRIVER_MODULE(iicbus, bti2c, iicbus_driver, iicbus_devclass, 0, 0); 275 DRIVER_MODULE(iicbus, smbtx, iicbus_driver, iicbus_devclass, 0, 0); 276