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/lock.h> 38 #include <sys/malloc.h> 39 #include <sys/module.h> 40 #include <sys/mutex.h> 41 #include <sys/bus.h> 42 43 #include <dev/iicbus/iiconf.h> 44 #include <dev/iicbus/iicbus.h> 45 46 #include "iicbus_if.h" 47 48 /* See comments below for why auto-scanning is a bad idea. */ 49 #define SCAN_IICBUS 0 50 51 static int 52 iicbus_probe(device_t dev) 53 { 54 55 device_set_desc(dev, "Philips I2C bus"); 56 return (0); 57 } 58 59 #if SCAN_IICBUS 60 static int 61 iic_probe_device(device_t dev, u_char addr) 62 { 63 int count; 64 char byte; 65 66 if ((addr & 1) == 0) { 67 /* is device writable? */ 68 if (!iicbus_start(dev, (u_char)addr, 0)) { 69 iicbus_stop(dev); 70 return (1); 71 } 72 } else { 73 /* is device readable? */ 74 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count)) 75 return (1); 76 } 77 78 return (0); 79 } 80 #endif 81 82 /* 83 * We add all the devices which we know about. 84 * The generic attach routine will attach them if they are alive. 85 */ 86 static int 87 iicbus_attach(device_t dev) 88 { 89 #if SCAN_IICBUS 90 unsigned char addr; 91 #endif 92 struct iicbus_softc *sc = IICBUS_SOFTC(dev); 93 94 sc->dev = dev; 95 mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF); 96 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 97 98 /* device probing is meaningless since the bus is supposed to be 99 * hot-plug. Moreover, some I2C chips do not appreciate random 100 * accesses like stop after start to fast, reads for less than 101 * x bytes... 102 */ 103 #if SCAN_IICBUS 104 printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 105 106 /* probe any devices */ 107 for (addr = 16; addr < 240; addr++) { 108 if (iic_probe_device(dev, (u_char)addr)) { 109 printf(" <%x>", addr); 110 } 111 } 112 printf("\n"); 113 #endif 114 bus_generic_probe(dev); 115 bus_enumerate_hinted_children(dev); 116 bus_generic_attach(dev); 117 return (0); 118 } 119 120 static int 121 iicbus_detach(device_t dev) 122 { 123 struct iicbus_softc *sc = IICBUS_SOFTC(dev); 124 125 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 126 bus_generic_detach(dev); 127 mtx_destroy(&sc->lock); 128 return (0); 129 } 130 131 static int 132 iicbus_print_child(device_t dev, device_t child) 133 { 134 struct iicbus_ivar *devi = IICBUS_IVAR(child); 135 int retval = 0; 136 137 retval += bus_print_child_header(dev, child); 138 if (devi->addr != 0) 139 retval += printf(" at addr %#x", devi->addr); 140 retval += bus_print_child_footer(dev, child); 141 142 return (retval); 143 } 144 145 static void 146 iicbus_probe_nomatch(device_t bus, device_t child) 147 { 148 struct iicbus_ivar *devi = IICBUS_IVAR(child); 149 150 device_printf(bus, "<unknown card>"); 151 printf(" at addr %#x\n", devi->addr); 152 return; 153 } 154 155 static int 156 iicbus_child_location_str(device_t bus, device_t child, char *buf, 157 size_t buflen) 158 { 159 struct iicbus_ivar *devi = IICBUS_IVAR(child); 160 161 snprintf(buf, buflen, "addr=%#x", devi->addr); 162 return (0); 163 } 164 165 static int 166 iicbus_child_pnpinfo_str(device_t bus, device_t child, char *buf, 167 size_t buflen) 168 { 169 *buf = '\0'; 170 return (0); 171 } 172 173 static int 174 iicbus_read_ivar(device_t bus, device_t child, int which, u_char *result) 175 { 176 struct iicbus_ivar *devi = IICBUS_IVAR(child); 177 178 switch (which) { 179 default: 180 return (EINVAL); 181 case IICBUS_IVAR_ADDR: 182 *(uint32_t *)result = devi->addr; 183 break; 184 } 185 return (0); 186 } 187 188 static device_t 189 iicbus_add_child(device_t dev, int order, const char *name, int unit) 190 { 191 device_t child; 192 struct iicbus_ivar *devi; 193 194 child = device_add_child_ordered(dev, order, name, unit); 195 if (child == NULL) 196 return (child); 197 devi = malloc(sizeof(struct iicbus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO); 198 if (devi == NULL) { 199 device_delete_child(dev, child); 200 return (0); 201 } 202 device_set_ivars(child, devi); 203 return (child); 204 } 205 206 static void 207 iicbus_hinted_child(device_t bus, const char *dname, int dunit) 208 { 209 device_t child; 210 struct iicbus_ivar *devi; 211 212 child = BUS_ADD_CHILD(bus, 0, dname, dunit); 213 devi = IICBUS_IVAR(child); 214 resource_int_value(dname, dunit, "addr", &devi->addr); 215 } 216 217 int 218 iicbus_generic_intr(device_t dev, int event, char *buf) 219 { 220 221 return (0); 222 } 223 224 int 225 iicbus_null_callback(device_t dev, int index, caddr_t data) 226 { 227 228 return (0); 229 } 230 231 int 232 iicbus_null_repeated_start(device_t dev, u_char addr) 233 { 234 235 return (IIC_ENOTSUPP); 236 } 237 238 static device_method_t iicbus_methods[] = { 239 /* device interface */ 240 DEVMETHOD(device_probe, iicbus_probe), 241 DEVMETHOD(device_attach, iicbus_attach), 242 DEVMETHOD(device_detach, iicbus_detach), 243 244 /* bus interface */ 245 DEVMETHOD(bus_add_child, iicbus_add_child), 246 DEVMETHOD(bus_driver_added, bus_generic_driver_added), 247 DEVMETHOD(bus_print_child, iicbus_print_child), 248 DEVMETHOD(bus_probe_nomatch, iicbus_probe_nomatch), 249 DEVMETHOD(bus_read_ivar, iicbus_read_ivar), 250 DEVMETHOD(bus_child_pnpinfo_str, iicbus_child_pnpinfo_str), 251 DEVMETHOD(bus_child_location_str, iicbus_child_location_str), 252 DEVMETHOD(bus_hinted_child, iicbus_hinted_child), 253 254 /* iicbus interface */ 255 DEVMETHOD(iicbus_transfer, iicbus_transfer), 256 257 { 0, 0 } 258 }; 259 260 driver_t iicbus_driver = { 261 "iicbus", 262 iicbus_methods, 263 sizeof(struct iicbus_softc), 264 }; 265 266 devclass_t iicbus_devclass; 267 268 MODULE_VERSION(iicbus, IICBUS_MODVER); 269