| 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 | * $FreeBSD: src/sys/dev/iicbus/iicbus.c,v 1.13 1999/12/03 08:41:02 mdodd Exp $ |
| 27 | * $DragonFly: src/sys/bus/iicbus/iicbus.c,v 1.4 2005/02/17 13:59:35 joerg Exp $ |
| 28 | * |
| 29 | */ |
| 30 | |
| 31 | /* |
| 32 | * Autoconfiguration and support routines for the Philips serial I2C bus |
| 33 | */ |
| 34 | |
| 35 | #include <sys/param.h> |
| 36 | #include <sys/systm.h> |
| 37 | #include <sys/kernel.h> |
| 38 | #include <sys/module.h> |
| 39 | #include <sys/bus.h> |
| 40 | |
| 41 | #include <machine/clock.h> |
| 42 | |
| 43 | #include "iiconf.h" |
| 44 | #include "iicbus.h" |
| 45 | |
| 46 | #include "iicbus_if.h" |
| 47 | |
| 48 | #define DEVTOIICBUS(dev) ((struct iicbus_device*)device_get_ivars(dev)) |
| 49 | |
| 50 | /* |
| 51 | * structure used to attach devices to the I2C bus |
| 52 | */ |
| 53 | struct iicbus_device { |
| 54 | const char *iicd_name; /* device name */ |
| 55 | int iicd_class; /* driver or slave device class */ |
| 56 | const char *iicd_desc; /* device descriptor */ |
| 57 | u_char iicd_addr; /* address of the device */ |
| 58 | int iicd_waitack; /* wait for ack timeout or delay */ |
| 59 | int iicd_alive; /* 1 if device found */ |
| 60 | }; |
| 61 | |
| 62 | /* |
| 63 | * Common I2C addresses |
| 64 | */ |
| 65 | #define I2C_GENERAL_CALL 0x0 |
| 66 | #define PCF_MASTER_ADDRESS 0xaa |
| 67 | #define FIRST_SLAVE_ADDR 0x2 |
| 68 | |
| 69 | #define LAST_SLAVE_ADDR 255 |
| 70 | |
| 71 | #define IICBUS_UNKNOWN_CLASS 0 |
| 72 | #define IICBUS_DEVICE_CLASS 1 |
| 73 | #define IICBUS_DRIVER_CLASS 2 |
| 74 | |
| 75 | /* |
| 76 | * list of known devices |
| 77 | * |
| 78 | * XXX only one smb driver should exist for each I2C interface |
| 79 | */ |
| 80 | static struct iicbus_device iicbus_children[] = { |
| 81 | { "iicsmb", IICBUS_DRIVER_CLASS, "I2C to SMB bridge" }, |
| 82 | { "iic", IICBUS_DRIVER_CLASS, "I2C general purpose I/O" }, |
| 83 | #if 0 |
| 84 | { "ic", IICBUS_DEVICE_CLASS, "network interface", PCF_MASTER_ADDRESS }, |
| 85 | #endif |
| 86 | { NULL, 0 } |
| 87 | }; |
| 88 | |
| 89 | static devclass_t iicbus_devclass; |
| 90 | |
| 91 | /* |
| 92 | * Device methods |
| 93 | */ |
| 94 | static int iicbus_probe(device_t); |
| 95 | static int iicbus_attach(device_t); |
| 96 | static int iicbus_print_child(device_t, device_t); |
| 97 | static int iicbus_read_ivar(device_t , device_t, int, u_long *); |
| 98 | static int iicbus_write_ivar(device_t , device_t, int, u_long); |
| 99 | |
| 100 | static device_method_t iicbus_methods[] = { |
| 101 | /* device interface */ |
| 102 | DEVMETHOD(device_probe, iicbus_probe), |
| 103 | DEVMETHOD(device_attach, iicbus_attach), |
| 104 | DEVMETHOD(device_detach, bus_generic_detach), |
| 105 | DEVMETHOD(device_shutdown, bus_generic_shutdown), |
| 106 | |
| 107 | /* bus interface */ |
| 108 | DEVMETHOD(bus_print_child, iicbus_print_child), |
| 109 | DEVMETHOD(bus_read_ivar, iicbus_read_ivar), |
| 110 | DEVMETHOD(bus_write_ivar, iicbus_write_ivar), |
| 111 | |
| 112 | { 0, 0 } |
| 113 | }; |
| 114 | |
| 115 | static driver_t iicbus_driver = { |
| 116 | "iicbus", |
| 117 | iicbus_methods, |
| 118 | sizeof(struct iicbus_softc), |
| 119 | }; |
| 120 | |
| 121 | static int |
| 122 | iicbus_probe(device_t dev) |
| 123 | { |
| 124 | device_set_desc(dev, "Philips I2C bus"); |
| 125 | |
| 126 | return (0); |
| 127 | } |
| 128 | |
| 129 | #if 0 |
| 130 | static int |
| 131 | iic_probe_device(device_t dev, u_char addr) |
| 132 | { |
| 133 | int count; |
| 134 | char byte; |
| 135 | |
| 136 | if ((addr & 1) == 0) { |
| 137 | /* is device writable? */ |
| 138 | if (!iicbus_start(dev, (u_char)addr, 0)) { |
| 139 | iicbus_stop(dev); |
| 140 | return (1); |
| 141 | } |
| 142 | } else { |
| 143 | /* is device readable? */ |
| 144 | if (!iicbus_block_read(dev, (u_char)addr, &byte, 1, &count)) |
| 145 | return (1); |
| 146 | } |
| 147 | |
| 148 | return (0); |
| 149 | } |
| 150 | #endif |
| 151 | |
| 152 | /* |
| 153 | * We add all the devices which we know about. |
| 154 | * The generic attach routine will attach them if they are alive. |
| 155 | */ |
| 156 | static int |
| 157 | iicbus_attach(device_t dev) |
| 158 | { |
| 159 | struct iicbus_device *iicdev; |
| 160 | device_t child; |
| 161 | |
| 162 | iicbus_reset(dev, IIC_FASTEST, 0, NULL); |
| 163 | |
| 164 | /* device probing is meaningless since the bus is supposed to be |
| 165 | * hot-plug. Moreover, some I2C chips do not appreciate random |
| 166 | * accesses like stop after start to fast, reads for less than |
| 167 | * x bytes... |
| 168 | */ |
| 169 | #if 0 |
| 170 | printf("Probing for devices on iicbus%d:", device_get_unit(dev)); |
| 171 | |
| 172 | /* probe any devices */ |
| 173 | for (addr = FIRST_SLAVE_ADDR; addr <= LAST_SLAVE_ADDR; addr++) { |
| 174 | if (iic_probe_device(dev, (u_char)addr)) { |
| 175 | printf(" <%x>", addr); |
| 176 | } |
| 177 | } |
| 178 | printf("\n"); |
| 179 | #endif |
| 180 | |
| 181 | /* attach known devices */ |
| 182 | for (iicdev = iicbus_children; iicdev->iicd_name; iicdev++) { |
| 183 | switch (iicdev->iicd_class) { |
| 184 | case IICBUS_DEVICE_CLASS: |
| 185 | /* check if the devclass exists */ |
| 186 | if (devclass_find(iicdev->iicd_name)) |
| 187 | iicdev->iicd_alive = 1; |
| 188 | else if (bootverbose) |
| 189 | printf("iicbus: %s devclass not found\n", |
| 190 | iicdev->iicd_name); |
| 191 | break; |
| 192 | |
| 193 | case IICBUS_DRIVER_CLASS: |
| 194 | /* check if the devclass exists */ |
| 195 | if (devclass_find(iicdev->iicd_name)) |
| 196 | iicdev->iicd_alive = 1; |
| 197 | else if (bootverbose) |
| 198 | printf("iicbus: %s devclass not found\n", |
| 199 | iicdev->iicd_name); |
| 200 | break; |
| 201 | |
| 202 | default: |
| 203 | panic("%s: unknown class!", __func__); |
| 204 | } |
| 205 | |
| 206 | if (iicdev->iicd_alive) { |
| 207 | child = device_add_child(dev, iicdev->iicd_name, -1); |
| 208 | device_set_ivars(child, iicdev); |
| 209 | device_set_desc(child, iicdev->iicd_desc); |
| 210 | } |
| 211 | } |
| 212 | bus_generic_attach(dev); |
| 213 | |
| 214 | return (0); |
| 215 | } |
| 216 | |
| 217 | int |
| 218 | iicbus_generic_intr(device_t dev, int event, char *buf) |
| 219 | { |
| 220 | return (0); |
| 221 | } |
| 222 | |
| 223 | int |
| 224 | iicbus_null_callback(device_t dev, int index, caddr_t data) |
| 225 | { |
| 226 | return (0); |
| 227 | } |
| 228 | |
| 229 | int |
| 230 | iicbus_null_repeated_start(device_t dev, u_char addr) |
| 231 | { |
| 232 | return (IIC_ENOTSUPP); |
| 233 | } |
| 234 | |
| 235 | static int |
| 236 | iicbus_print_child(device_t bus, device_t dev) |
| 237 | { |
| 238 | struct iicbus_device* iicdev = DEVTOIICBUS(dev); |
| 239 | int retval = 0; |
| 240 | |
| 241 | retval += bus_print_child_header(bus, dev); |
| 242 | |
| 243 | switch (iicdev->iicd_class) { |
| 244 | case IICBUS_DEVICE_CLASS: |
| 245 | retval += printf(" on %s addr 0x%x\n", |
| 246 | device_get_nameunit(bus), iicdev->iicd_addr); |
| 247 | break; |
| 248 | |
| 249 | case IICBUS_DRIVER_CLASS: |
| 250 | retval += bus_print_child_footer(bus, dev); |
| 251 | break; |
| 252 | |
| 253 | default: |
| 254 | panic("%s: unknown class!", __func__); |
| 255 | } |
| 256 | |
| 257 | return (retval); |
| 258 | } |
| 259 | |
| 260 | static int |
| 261 | iicbus_read_ivar(device_t bus, device_t dev, int index, u_long* result) |
| 262 | { |
| 263 | struct iicbus_device* iicdev = DEVTOIICBUS(dev); |
| 264 | |
| 265 | switch (index) { |
| 266 | case IICBUS_IVAR_ADDR: |
| 267 | *result = (u_long)iicdev->iicd_addr; |
| 268 | break; |
| 269 | |
| 270 | default: |
| 271 | return (ENOENT); |
| 272 | } |
| 273 | |
| 274 | return (0); |
| 275 | } |
| 276 | |
| 277 | static int |
| 278 | iicbus_write_ivar(device_t bus, device_t dev, int index, u_long val) |
| 279 | { |
| 280 | switch (index) { |
| 281 | default: |
| 282 | return (ENOENT); |
| 283 | } |
| 284 | |
| 285 | return (0); |
| 286 | } |
| 287 | |
| 288 | DRIVER_MODULE(iicbus, pcf, iicbus_driver, iicbus_devclass, 0, 0); |
| 289 | DRIVER_MODULE(iicbus, iicbb, iicbus_driver, iicbus_devclass, 0, 0); |
| 290 | DRIVER_MODULE(iicbus, bti2c, iicbus_driver, iicbus_devclass, 0, 0); |