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 96 sc->dev = dev; 97 mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF); 98 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 99 100 /* device probing is meaningless since the bus is supposed to be 101 * hot-plug. Moreover, some I2C chips do not appreciate random 102 * accesses like stop after start to fast, reads for less than 103 * x bytes... 104 */ 105 #if SCAN_IICBUS 106 printf("Probing for devices on iicbus%d:", device_get_unit(dev)); 107 108 /* probe any devices */ 109 for (addr = 16; addr < 240; addr++) { 110 if (iic_probe_device(dev, (u_char)addr)) { 111 printf(" <%x>", addr); 112 } 113 } 114 printf("\n"); 115 #endif 116 bus_generic_probe(dev); 117 bus_enumerate_hinted_children(dev); 118 bus_generic_attach(dev); 119 return (0); 120 } 121 122 static int 123 iicbus_detach(device_t dev) 124 { 125 struct iicbus_softc *sc = IICBUS_SOFTC(dev); 126 127 iicbus_reset(dev, IIC_FASTEST, 0, NULL); 128 bus_generic_detach(dev); 129 mtx_destroy(&sc->lock); 130 return (0); 131 } 132 133 static int 134 iicbus_print_child(device_t dev, device_t child) 135 { 136 struct iicbus_ivar *devi = IICBUS_IVAR(child); 137 int retval = 0; 138 139 retval += bus_print_child_header(dev, child); 140 if (devi->addr != 0) 141 retval += printf(" at addr %#x", devi->addr); 142 retval += bus_print_child_footer(dev, child); 143 144 return (retval); 145 } 146 147 static void 148 iicbus_probe_nomatch(device_t bus, device_t child) 149 { 150 struct iicbus_ivar *devi = IICBUS_IVAR(child); 151 152 device_printf(bus, "<unknown card>"); 153 printf(" at addr %#x\n", devi->addr); 154 return; 155 } 156 157 static int 158 iicbus_child_location_str(device_t bus, device_t child, char *buf, 159 size_t buflen) 160 { 161 struct iicbus_ivar *devi = IICBUS_IVAR(child); 162 163 snprintf(buf, buflen, "addr=%#x", devi->addr); 164 return (0); 165 } 166 167 static int 168 iicbus_child_pnpinfo_str(device_t bus, device_t child, char *buf, 169 size_t buflen) 170 { 171 *buf = '\0'; 172 return (0); 173 } 174 175 static int 176 iicbus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result) 177 { 178 struct iicbus_ivar *devi = IICBUS_IVAR(child); 179 180 switch (which) { 181 default: 182 return (EINVAL); 183 case IICBUS_IVAR_ADDR: 184 *(uint32_t *)result = devi->addr; 185 break; 186 } 187 return (0); 188 } 189 190 static device_t 191 iicbus_add_child(device_t dev, int order, const char *name, int unit) 192 { 193 device_t child; 194 struct iicbus_ivar *devi; 195 196 child = device_add_child_ordered(dev, order, name, unit); 197 if (child == NULL) 198 return (child); 199 devi = malloc(sizeof(struct iicbus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO); 200 if (devi == NULL) { 201 device_delete_child(dev, child); 202 return (0); 203 } 204 device_set_ivars(child, devi); 205 return (child); 206 } 207 208 static void 209 iicbus_hinted_child(device_t bus, const char *dname, int dunit) 210 { 211 device_t child; 212 struct iicbus_ivar *devi; 213 214 child = BUS_ADD_CHILD(bus, 0, dname, dunit); 215 devi = IICBUS_IVAR(child); 216 resource_int_value(dname, dunit, "addr", &devi->addr); 217 } 218 219 int 220 iicbus_generic_intr(device_t dev, int event, char *buf) 221 { 222 223 return (0); 224 } 225 226 int 227 iicbus_null_callback(device_t dev, int index, caddr_t data) 228 { 229 230 return (0); 231 } 232 233 int 234 iicbus_null_repeated_start(device_t dev, u_char addr) 235 { 236 237 return (IIC_ENOTSUPP); 238 } 239 240 static device_method_t iicbus_methods[] = { 241 /* device interface */ 242 DEVMETHOD(device_probe, iicbus_probe), 243 DEVMETHOD(device_attach, iicbus_attach), 244 DEVMETHOD(device_detach, iicbus_detach), 245 246 /* bus interface */ 247 DEVMETHOD(bus_add_child, iicbus_add_child), 248 DEVMETHOD(bus_driver_added, bus_generic_driver_added), 249 DEVMETHOD(bus_print_child, iicbus_print_child), 250 DEVMETHOD(bus_probe_nomatch, iicbus_probe_nomatch), 251 DEVMETHOD(bus_read_ivar, iicbus_read_ivar), 252 DEVMETHOD(bus_child_pnpinfo_str, iicbus_child_pnpinfo_str), 253 DEVMETHOD(bus_child_location_str, iicbus_child_location_str), 254 DEVMETHOD(bus_hinted_child, iicbus_hinted_child), 255 256 /* iicbus interface */ 257 DEVMETHOD(iicbus_transfer, iicbus_transfer), 258 259 { 0, 0 } 260 }; 261 262 driver_t iicbus_driver = { 263 "iicbus", 264 iicbus_methods, 265 sizeof(struct iicbus_softc), 266 }; 267 268 devclass_t iicbus_devclass; 269 270 MODULE_VERSION(iicbus, IICBUS_MODVER); 271 DRIVER_MODULE(iicbus, iichb, iicbus_driver, iicbus_devclass, 0, 0); 272 273