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