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 * $FreeBSD$ 27 * 28 */ 29 30 /* 31 * I2C to SMB bridge 32 * 33 * Example: 34 * 35 * smb bttv 36 * \ / 37 * smbus 38 * / \ 39 * iicsmb bti2c 40 * | 41 * iicbus 42 * / | \ 43 * iicbb pcf ... 44 * | 45 * lpbb 46 */ 47 48 #include <sys/param.h> 49 #include <sys/bus.h> 50 #include <sys/kernel.h> 51 #include <sys/lock.h> 52 #include <sys/module.h> 53 #include <sys/mutex.h> 54 #include <sys/systm.h> 55 #include <sys/uio.h> 56 57 #include <dev/iicbus/iiconf.h> 58 #include <dev/iicbus/iicbus.h> 59 60 #include <dev/smbus/smbconf.h> 61 62 #include "iicbus_if.h" 63 #include "smbus_if.h" 64 65 struct iicsmb_softc { 66 67 #define SMB_WAITING_ADDR 0x0 68 #define SMB_WAITING_LOW 0x1 69 #define SMB_WAITING_HIGH 0x2 70 #define SMB_DONE 0x3 71 int state; 72 73 u_char devaddr; /* slave device address */ 74 75 char low; /* low byte received first */ 76 char high; /* high byte */ 77 78 struct mtx lock; 79 device_t smbus; 80 }; 81 82 static int iicsmb_probe(device_t); 83 static int iicsmb_attach(device_t); 84 static int iicsmb_detach(device_t); 85 static void iicsmb_identify(driver_t *driver, device_t parent); 86 87 static int iicsmb_intr(device_t dev, int event, char *buf); 88 static int iicsmb_callback(device_t dev, int index, void *data); 89 static int iicsmb_quick(device_t dev, u_char slave, int how); 90 static int iicsmb_sendb(device_t dev, u_char slave, char byte); 91 static int iicsmb_recvb(device_t dev, u_char slave, char *byte); 92 static int iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte); 93 static int iicsmb_writew(device_t dev, u_char slave, char cmd, short word); 94 static int iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte); 95 static int iicsmb_readw(device_t dev, u_char slave, char cmd, short *word); 96 static int iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata); 97 static int iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf); 98 static int iicsmb_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf); 99 100 static devclass_t iicsmb_devclass; 101 102 static device_method_t iicsmb_methods[] = { 103 /* device interface */ 104 DEVMETHOD(device_identify, iicsmb_identify), 105 DEVMETHOD(device_probe, iicsmb_probe), 106 DEVMETHOD(device_attach, iicsmb_attach), 107 DEVMETHOD(device_detach, iicsmb_detach), 108 109 /* bus interface */ 110 DEVMETHOD(bus_driver_added, bus_generic_driver_added), 111 DEVMETHOD(bus_print_child, bus_generic_print_child), 112 113 /* iicbus interface */ 114 DEVMETHOD(iicbus_intr, iicsmb_intr), 115 116 /* smbus interface */ 117 DEVMETHOD(smbus_callback, iicsmb_callback), 118 DEVMETHOD(smbus_quick, iicsmb_quick), 119 DEVMETHOD(smbus_sendb, iicsmb_sendb), 120 DEVMETHOD(smbus_recvb, iicsmb_recvb), 121 DEVMETHOD(smbus_writeb, iicsmb_writeb), 122 DEVMETHOD(smbus_writew, iicsmb_writew), 123 DEVMETHOD(smbus_readb, iicsmb_readb), 124 DEVMETHOD(smbus_readw, iicsmb_readw), 125 DEVMETHOD(smbus_pcall, iicsmb_pcall), 126 DEVMETHOD(smbus_bwrite, iicsmb_bwrite), 127 DEVMETHOD(smbus_bread, iicsmb_bread), 128 129 { 0, 0 } 130 }; 131 132 static driver_t iicsmb_driver = { 133 "iicsmb", 134 iicsmb_methods, 135 sizeof(struct iicsmb_softc), 136 }; 137 138 #define IICBUS_TIMEOUT 100 /* us */ 139 140 static void 141 iicsmb_identify(driver_t *driver, device_t parent) 142 { 143 144 if (device_find_child(parent, "iicsmb", -1) == NULL) 145 BUS_ADD_CHILD(parent, 0, "iicsmb", -1); 146 } 147 148 static int 149 iicsmb_probe(device_t dev) 150 { 151 device_set_desc(dev, "SMBus over I2C bridge"); 152 return (BUS_PROBE_NOWILDCARD); 153 } 154 155 static int 156 iicsmb_attach(device_t dev) 157 { 158 struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); 159 160 mtx_init(&sc->lock, "iicsmb", NULL, MTX_DEF); 161 162 sc->smbus = device_add_child(dev, "smbus", -1); 163 164 /* probe and attach the smbus */ 165 bus_generic_attach(dev); 166 167 return (0); 168 } 169 170 static int 171 iicsmb_detach(device_t dev) 172 { 173 struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); 174 175 bus_generic_detach(dev); 176 if (sc->smbus) { 177 device_delete_child(dev, sc->smbus); 178 } 179 mtx_destroy(&sc->lock); 180 181 return (0); 182 } 183 184 /* 185 * iicsmb_intr() 186 * 187 * iicbus interrupt handler 188 */ 189 static int 190 iicsmb_intr(device_t dev, int event, char *buf) 191 { 192 struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); 193 194 mtx_lock(&sc->lock); 195 switch (event) { 196 case INTR_GENERAL: 197 case INTR_START: 198 sc->state = SMB_WAITING_ADDR; 199 break; 200 201 case INTR_STOP: 202 /* call smbus intr handler */ 203 smbus_intr(sc->smbus, sc->devaddr, 204 sc->low, sc->high, SMB_ENOERR); 205 break; 206 207 case INTR_RECEIVE: 208 switch (sc->state) { 209 case SMB_DONE: 210 /* XXX too much data, discard */ 211 printf("%s: too much data from 0x%x\n", __func__, 212 sc->devaddr & 0xff); 213 goto end; 214 215 case SMB_WAITING_ADDR: 216 sc->devaddr = (u_char)*buf; 217 sc->state = SMB_WAITING_LOW; 218 break; 219 220 case SMB_WAITING_LOW: 221 sc->low = *buf; 222 sc->state = SMB_WAITING_HIGH; 223 break; 224 225 case SMB_WAITING_HIGH: 226 sc->high = *buf; 227 sc->state = SMB_DONE; 228 break; 229 } 230 end: 231 break; 232 233 case INTR_TRANSMIT: 234 case INTR_NOACK: 235 break; 236 237 case INTR_ERROR: 238 switch (*buf) { 239 case IIC_EBUSERR: 240 smbus_intr(sc->smbus, sc->devaddr, 0, 0, SMB_EBUSERR); 241 break; 242 243 default: 244 printf("%s unknown error 0x%x!\n", __func__, 245 (int)*buf); 246 break; 247 } 248 break; 249 250 default: 251 panic("%s: unknown event (%d)!", __func__, event); 252 } 253 mtx_unlock(&sc->lock); 254 255 return (0); 256 } 257 258 static int 259 iicsmb_callback(device_t dev, int index, void *data) 260 { 261 device_t parent = device_get_parent(dev); 262 int error = 0; 263 int how; 264 265 switch (index) { 266 case SMB_REQUEST_BUS: 267 /* request underlying iicbus */ 268 how = *(int *)data; 269 error = iicbus_request_bus(parent, dev, how); 270 break; 271 272 case SMB_RELEASE_BUS: 273 /* release underlying iicbus */ 274 error = iicbus_release_bus(parent, dev); 275 break; 276 277 default: 278 error = EINVAL; 279 } 280 281 return (error); 282 } 283 284 static int 285 iicsmb_quick(device_t dev, u_char slave, int how) 286 { 287 device_t parent = device_get_parent(dev); 288 int error; 289 290 switch (how) { 291 case SMB_QWRITE: 292 error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT); 293 break; 294 295 case SMB_QREAD: 296 error = iicbus_start(parent, slave | LSB, IICBUS_TIMEOUT); 297 break; 298 299 default: 300 error = EINVAL; 301 break; 302 } 303 304 if (!error) 305 error = iicbus_stop(parent); 306 307 return (error); 308 } 309 310 static int 311 iicsmb_sendb(device_t dev, u_char slave, char byte) 312 { 313 device_t parent = device_get_parent(dev); 314 int error, sent; 315 316 error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT); 317 318 if (!error) { 319 error = iicbus_write(parent, &byte, 1, &sent, IICBUS_TIMEOUT); 320 321 iicbus_stop(parent); 322 } 323 324 return (error); 325 } 326 327 static int 328 iicsmb_recvb(device_t dev, u_char slave, char *byte) 329 { 330 device_t parent = device_get_parent(dev); 331 int error, read; 332 333 error = iicbus_start(parent, slave | LSB, 0); 334 335 if (!error) { 336 error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, IICBUS_TIMEOUT); 337 338 iicbus_stop(parent); 339 } 340 341 return (error); 342 } 343 344 static int 345 iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte) 346 { 347 device_t parent = device_get_parent(dev); 348 int error, sent; 349 350 error = iicbus_start(parent, slave & ~LSB, 0); 351 352 if (!error) { 353 if (!(error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 354 error = iicbus_write(parent, &byte, 1, &sent, IICBUS_TIMEOUT); 355 356 iicbus_stop(parent); 357 } 358 359 return (error); 360 } 361 362 static int 363 iicsmb_writew(device_t dev, u_char slave, char cmd, short word) 364 { 365 device_t parent = device_get_parent(dev); 366 int error, sent; 367 368 char low = (char)(word & 0xff); 369 char high = (char)((word & 0xff00) >> 8); 370 371 error = iicbus_start(parent, slave & ~LSB, 0); 372 373 if (!error) { 374 if (!(error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 375 if (!(error = iicbus_write(parent, &low, 1, &sent, IICBUS_TIMEOUT))) 376 error = iicbus_write(parent, &high, 1, &sent, IICBUS_TIMEOUT); 377 378 iicbus_stop(parent); 379 } 380 381 return (error); 382 } 383 384 static int 385 iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte) 386 { 387 device_t parent = device_get_parent(dev); 388 int error, sent, read; 389 390 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 391 return (error); 392 393 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 394 goto error; 395 396 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 397 goto error; 398 399 if ((error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) 400 goto error; 401 402 error: 403 iicbus_stop(parent); 404 return (error); 405 } 406 407 #define BUF2SHORT(low,high) \ 408 ((short)(((high) & 0xff) << 8) | (short)((low) & 0xff)) 409 410 static int 411 iicsmb_readw(device_t dev, u_char slave, char cmd, short *word) 412 { 413 device_t parent = device_get_parent(dev); 414 int error, sent, read; 415 char buf[2]; 416 417 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 418 return (error); 419 420 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 421 goto error; 422 423 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 424 goto error; 425 426 if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) 427 goto error; 428 429 /* first, receive low, then high byte */ 430 *word = BUF2SHORT(buf[0], buf[1]); 431 432 error: 433 iicbus_stop(parent); 434 return (error); 435 } 436 437 static int 438 iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata) 439 { 440 device_t parent = device_get_parent(dev); 441 int error, sent, read; 442 char buf[2]; 443 444 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 445 return (error); 446 447 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 448 goto error; 449 450 /* first, send low, then high byte */ 451 buf[0] = (char)(sdata & 0xff); 452 buf[1] = (char)((sdata & 0xff00) >> 8); 453 454 if ((error = iicbus_write(parent, buf, 2, &sent, IICBUS_TIMEOUT))) 455 goto error; 456 457 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 458 goto error; 459 460 if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) 461 goto error; 462 463 /* first, receive low, then high byte */ 464 *rdata = BUF2SHORT(buf[0], buf[1]); 465 466 error: 467 iicbus_stop(parent); 468 return (error); 469 } 470 471 static int 472 iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf) 473 { 474 device_t parent = device_get_parent(dev); 475 int error, sent; 476 477 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 478 goto error; 479 480 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 481 goto error; 482 483 if ((error = iicbus_write(parent, buf, (int)count, &sent, IICBUS_TIMEOUT))) 484 goto error; 485 486 if ((error = iicbus_stop(parent))) 487 goto error; 488 489 error: 490 return (error); 491 } 492 493 static int 494 iicsmb_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf) 495 { 496 device_t parent = device_get_parent(dev); 497 int error, sent, read; 498 499 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 500 return (error); 501 502 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 503 goto error; 504 505 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 506 goto error; 507 508 if ((error = iicbus_read(parent, buf, (int)*count, &read, 509 IIC_LAST_READ, IICBUS_TIMEOUT))) 510 goto error; 511 *count = read; 512 513 error: 514 iicbus_stop(parent); 515 return (error); 516 } 517 518 DRIVER_MODULE(iicsmb, iicbus, iicsmb_driver, iicsmb_devclass, 0, 0); 519 DRIVER_MODULE(smbus, iicsmb, smbus_driver, smbus_devclass, 0, 0); 520 MODULE_DEPEND(iicsmb, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); 521 MODULE_DEPEND(iicsmb, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER); 522 MODULE_VERSION(iicsmb, 1); 523