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 57 /* Allow other subclasses to override this driver. */ 58 return (BUS_PROBE_GENERIC); 59 } 60 61 #if SCAN_IICBUS 62 static int 63 iic_probe_device(device_t dev, u_char addr) 64 { 65 int count; 66 char byte; 67 68 if ((addr & 1) == 0) { 69 /* is device writable? */ 70 if (!iicbus_start(dev, (u_char)addr, 0)) { 71 iicbus_stop(dev); 72 return (1); 73 } 74 } else { 75 /* is device readable? */ 76 if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count)) 77 return (1); 78 } 79 80 return (0); 81 } 82 #endif 83 84 /* 85 * We add all the devices which we know about. 86 * The generic attach routine will attach them if they are alive. 87 */ 88 static int 89 iicbus_attach(device_t dev) 90 { 91 #if SCAN_IICBUS 92 unsigned char addr; 93 #endif 94 struct iicbus_softc *sc = IICBUS_SOFTC(dev); 95 int strict; 96 97 sc->dev = dev; 98 mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF); 99 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 100 if (resource_int_value(device_get_name(dev), 101 device_get_unit(dev), "strict", &strict) == 0) 102 sc->strict = strict; 103 else 104 sc->strict = 1; 105 106 /* device probing is meaningless since the bus is supposed to be 107 * hot-plug. Moreover, some I2C chips do not appreciate random 108 * accesses like stop after start to fast, reads for less than 109 * x bytes... 110 */ 111 #if SCAN_IICBUS 112 printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 113 114 /* probe any devices */ 115 for (addr = 16; addr < 240; addr++) { 116 if (iic_probe_device(dev, (u_char)addr)) { 117 printf(" <%x>", addr); 118 } 119 } 120 printf("\n"); 121 #endif 122 bus_generic_probe(dev); 123 bus_enumerate_hinted_children(dev); 124 bus_generic_attach(dev); 125 return (0); 126 } 127 128 static int 129 iicbus_detach(device_t dev) 130 { 131 struct iicbus_softc *sc = IICBUS_SOFTC(dev); 132 133 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 134 bus_generic_detach(dev); 135 mtx_destroy(&sc->lock); 136 return (0); 137 } 138 139 static int 140 iicbus_print_child(device_t dev, device_t child) 141 { 142 struct iicbus_ivar *devi = IICBUS_IVAR(child); 143 int retval = 0; 144 145 retval += bus_print_child_header(dev, child); 146 if (devi->addr != 0) 147 retval += printf(" at addr %#x", devi->addr); 148 retval += bus_print_child_footer(dev, child); 149 150 return (retval); 151 } 152 153 static void 154 iicbus_probe_nomatch(device_t bus, device_t child) 155 { 156 struct iicbus_ivar *devi = IICBUS_IVAR(child); 157 158 device_printf(bus, "<unknown card>"); 159 printf(" at addr %#x\n", devi->addr); 160 return; 161 } 162 163 static int 164 iicbus_child_location_str(device_t bus, device_t child, char *buf, 165 size_t buflen) 166 { 167 struct iicbus_ivar *devi = IICBUS_IVAR(child); 168 169 snprintf(buf, buflen, "addr=%#x", devi->addr); 170 return (0); 171 } 172 173 static int 174 iicbus_child_pnpinfo_str(device_t bus, device_t child, char *buf, 175 size_t buflen) 176 { 177 *buf = '\0'; 178 return (0); 179 } 180 181 static int 182 iicbus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result) 183 { 184 struct iicbus_ivar *devi = IICBUS_IVAR(child); 185 186 switch (which) { 187 default: 188 return (EINVAL); 189 case IICBUS_IVAR_ADDR: 190 *result = devi->addr; 191 break; 192 } 193 return (0); 194 } 195 196 static device_t 197 iicbus_add_child(device_t dev, u_int order, const char *name, int unit) 198 { 199 device_t child; 200 struct iicbus_ivar *devi; 201 202 child = device_add_child_ordered(dev, order, name, unit); 203 if (child == NULL) 204 return (child); 205 devi = malloc(sizeof(struct iicbus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO); 206 if (devi == NULL) { 207 device_delete_child(dev, child); 208 return (0); 209 } 210 device_set_ivars(child, devi); 211 return (child); 212 } 213 214 static void 215 iicbus_hinted_child(device_t bus, const char *dname, int dunit) 216 { 217 device_t child; 218 struct iicbus_ivar *devi; 219 220 child = BUS_ADD_CHILD(bus, 0, dname, dunit); 221 devi = IICBUS_IVAR(child); 222 resource_int_value(dname, dunit, "addr", &devi->addr); 223 } 224 225 int 226 iicbus_generic_intr(device_t dev, int event, char *buf) 227 { 228 229 return (0); 230 } 231 232 int 233 iicbus_null_callback(device_t dev, int index, caddr_t data) 234 { 235 236 return (0); 237 } 238 239 int 240 iicbus_null_repeated_start(device_t dev, u_char addr) 241 { 242 243 return (IIC_ENOTSUPP); 244 } 245 246 static device_method_t iicbus_methods[] = { 247 /* device interface */ 248 DEVMETHOD(device_probe, iicbus_probe), 249 DEVMETHOD(device_attach, iicbus_attach), 250 DEVMETHOD(device_detach, iicbus_detach), 251 252 /* bus interface */ 253 DEVMETHOD(bus_add_child, iicbus_add_child), 254 DEVMETHOD(bus_print_child, iicbus_print_child), 255 DEVMETHOD(bus_probe_nomatch, iicbus_probe_nomatch), 256 DEVMETHOD(bus_read_ivar, iicbus_read_ivar), 257 DEVMETHOD(bus_child_pnpinfo_str, iicbus_child_pnpinfo_str), 258 DEVMETHOD(bus_child_location_str, iicbus_child_location_str), 259 DEVMETHOD(bus_hinted_child, iicbus_hinted_child), 260 261 /* iicbus interface */ 262 DEVMETHOD(iicbus_transfer, iicbus_transfer), 263 264 DEVMETHOD_END 265 }; 266 267 driver_t iicbus_driver = { 268 "iicbus", 269 iicbus_methods, 270 sizeof(struct iicbus_softc), 271 }; 272 273 devclass_t iicbus_devclass; 274 275 MODULE_VERSION(iicbus, IICBUS_MODVER); 276 DRIVER_MODULE(iicbus, iichb, iicbus_driver, iicbus_devclass, 0, 0); 277 278