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: src/sys/dev/iicbus/iicsmb.c,v 1.18 2009/02/10 22:50:23 imp Exp $ 27 * $DragonFly: src/sys/bus/iicbus/iicsmb.c,v 1.5 2006/12/22 23:12:16 swildner Exp $ 28 * 29 */ 30 31 /* 32 * I2C to SMB bridge 33 * 34 * Example: 35 * 36 * smb bttv 37 * \ / 38 * smbus 39 * / \ 40 * iicsmb bti2c 41 * | 42 * iicbus 43 * / | \ 44 * iicbb pcf ... 45 * | 46 * lpbb 47 */ 48 49 #include <sys/param.h> 50 #include <sys/bus.h> 51 #include <sys/kernel.h> 52 #include <sys/module.h> 53 #include <sys/systm.h> 54 #include <sys/uio.h> 55 56 #include <bus/iicbus/iiconf.h> 57 #include <bus/iicbus/iicbus.h> 58 59 #include <bus/smbus/smbconf.h> 60 61 #include "iicbus_if.h" 62 #include "smbus_if.h" 63 64 struct iicsmb_softc { 65 66 #define SMB_WAITING_ADDR 0x0 67 #define SMB_WAITING_LOW 0x1 68 #define SMB_WAITING_HIGH 0x2 69 #define SMB_DONE 0x3 70 int state; 71 72 u_char devaddr; /* slave device address */ 73 74 char low; /* low byte received first */ 75 char high; /* high byte */ 76 77 device_t smbus; 78 }; 79 80 static int iicsmb_probe(device_t); 81 static int iicsmb_attach(device_t); 82 static int iicsmb_detach(device_t); 83 static void iicsmb_identify(driver_t *driver, device_t parent); 84 85 static int iicsmb_intr(device_t dev, int event, char *buf); 86 static int iicsmb_callback(device_t dev, int index, void *data); 87 static int iicsmb_quick(device_t dev, u_char slave, int how); 88 static int iicsmb_sendb(device_t dev, u_char slave, char byte); 89 static int iicsmb_recvb(device_t dev, u_char slave, char *byte); 90 static int iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte); 91 static int iicsmb_writew(device_t dev, u_char slave, char cmd, short word); 92 static int iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte); 93 static int iicsmb_readw(device_t dev, u_char slave, char cmd, short *word); 94 static int iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata); 95 static int iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf); 96 static int iicsmb_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf); 97 98 static devclass_t iicsmb_devclass; 99 100 static device_method_t iicsmb_methods[] = { 101 /* device interface */ 102 DEVMETHOD(device_identify, iicsmb_identify), 103 DEVMETHOD(device_probe, iicsmb_probe), 104 DEVMETHOD(device_attach, iicsmb_attach), 105 DEVMETHOD(device_detach, iicsmb_detach), 106 107 /* bus interface */ 108 DEVMETHOD(bus_driver_added, bus_generic_driver_added), 109 DEVMETHOD(bus_print_child, bus_generic_print_child), 110 111 /* iicbus interface */ 112 DEVMETHOD(iicbus_intr, iicsmb_intr), 113 114 /* smbus interface */ 115 DEVMETHOD(smbus_callback, iicsmb_callback), 116 DEVMETHOD(smbus_quick, iicsmb_quick), 117 DEVMETHOD(smbus_sendb, iicsmb_sendb), 118 DEVMETHOD(smbus_recvb, iicsmb_recvb), 119 DEVMETHOD(smbus_writeb, iicsmb_writeb), 120 DEVMETHOD(smbus_writew, iicsmb_writew), 121 DEVMETHOD(smbus_readb, iicsmb_readb), 122 DEVMETHOD(smbus_readw, iicsmb_readw), 123 DEVMETHOD(smbus_pcall, iicsmb_pcall), 124 DEVMETHOD(smbus_bwrite, iicsmb_bwrite), 125 DEVMETHOD(smbus_bread, iicsmb_bread), 126 127 { 0, 0 } 128 }; 129 130 static driver_t iicsmb_driver = { 131 "iicsmb", 132 iicsmb_methods, 133 sizeof(struct iicsmb_softc), 134 }; 135 136 #define IICBUS_TIMEOUT 100 /* us */ 137 138 static void 139 iicsmb_identify(driver_t *driver, device_t parent) 140 { 141 142 if (device_find_child(parent, "iicsmb", -1) == NULL) 143 BUS_ADD_CHILD(parent, parent, 0, "iicsmb", -1); 144 } 145 146 static int 147 iicsmb_probe(device_t dev) 148 { 149 device_set_desc(dev, "SMBus over I2C bridge"); 150 return (0); 151 } 152 153 static int 154 iicsmb_attach(device_t dev) 155 { 156 struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); 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 } 175 176 return (0); 177 } 178 179 /* 180 * iicsmb_intr() 181 * 182 * iicbus interrupt handler 183 */ 184 static int 185 iicsmb_intr(device_t dev, int event, char *buf) 186 { 187 struct iicsmb_softc *sc = (struct iicsmb_softc *)device_get_softc(dev); 188 189 switch (event) { 190 case INTR_GENERAL: 191 case INTR_START: 192 sc->state = SMB_WAITING_ADDR; 193 break; 194 195 case INTR_STOP: 196 /* call smbus intr handler */ 197 smbus_intr(sc->smbus, sc->devaddr, 198 sc->low, sc->high, SMB_ENOERR); 199 break; 200 201 case INTR_RECEIVE: 202 switch (sc->state) { 203 case SMB_DONE: 204 /* XXX too much data, discard */ 205 kprintf("%s: too much data from 0x%x\n", __func__, 206 sc->devaddr & 0xff); 207 goto end; 208 209 case SMB_WAITING_ADDR: 210 sc->devaddr = (u_char)*buf; 211 sc->state = SMB_WAITING_LOW; 212 break; 213 214 case SMB_WAITING_LOW: 215 sc->low = *buf; 216 sc->state = SMB_WAITING_HIGH; 217 break; 218 219 case SMB_WAITING_HIGH: 220 sc->high = *buf; 221 sc->state = SMB_DONE; 222 break; 223 } 224 end: 225 break; 226 227 case INTR_TRANSMIT: 228 case INTR_NOACK: 229 break; 230 231 case INTR_ERROR: 232 switch (*buf) { 233 case IIC_EBUSERR: 234 smbus_intr(sc->smbus, sc->devaddr, 0, 0, SMB_EBUSERR); 235 break; 236 237 default: 238 kprintf("%s unknown error 0x%x!\n", __func__, 239 (int)*buf); 240 break; 241 } 242 break; 243 244 default: 245 panic("%s: unknown event (%d)!", __func__, event); 246 } 247 248 return (0); 249 } 250 251 static int 252 iicsmb_callback(device_t dev, int index, void *data) 253 { 254 device_t parent = device_get_parent(dev); 255 int error = 0; 256 int how; 257 258 switch (index) { 259 case SMB_REQUEST_BUS: 260 /* request underlying iicbus */ 261 how = *(int *)data; 262 error = iicbus_request_bus(parent, dev, how); 263 break; 264 265 case SMB_RELEASE_BUS: 266 /* release underlying iicbus */ 267 error = iicbus_release_bus(parent, dev); 268 break; 269 270 default: 271 error = EINVAL; 272 } 273 274 return (error); 275 } 276 277 static int 278 iicsmb_quick(device_t dev, u_char slave, int how) 279 { 280 device_t parent = device_get_parent(dev); 281 int error; 282 283 switch (how) { 284 case SMB_QWRITE: 285 error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT); 286 break; 287 288 case SMB_QREAD: 289 error = iicbus_start(parent, slave | LSB, IICBUS_TIMEOUT); 290 break; 291 292 default: 293 error = EINVAL; 294 break; 295 } 296 297 if (!error) 298 error = iicbus_stop(parent); 299 300 return (error); 301 } 302 303 static int 304 iicsmb_sendb(device_t dev, u_char slave, char byte) 305 { 306 device_t parent = device_get_parent(dev); 307 int error, sent; 308 309 error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT); 310 311 if (!error) { 312 error = iicbus_write(parent, &byte, 1, &sent, IICBUS_TIMEOUT); 313 314 iicbus_stop(parent); 315 } 316 317 return (error); 318 } 319 320 static int 321 iicsmb_recvb(device_t dev, u_char slave, char *byte) 322 { 323 device_t parent = device_get_parent(dev); 324 int error, read; 325 326 error = iicbus_start(parent, slave | LSB, 0); 327 328 if (!error) { 329 error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, IICBUS_TIMEOUT); 330 331 iicbus_stop(parent); 332 } 333 334 return (error); 335 } 336 337 static int 338 iicsmb_writeb(device_t dev, u_char slave, char cmd, char byte) 339 { 340 device_t parent = device_get_parent(dev); 341 int error, sent; 342 343 error = iicbus_start(parent, slave & ~LSB, 0); 344 345 if (!error) { 346 if (!(error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 347 error = iicbus_write(parent, &byte, 1, &sent, IICBUS_TIMEOUT); 348 349 iicbus_stop(parent); 350 } 351 352 return (error); 353 } 354 355 static int 356 iicsmb_writew(device_t dev, u_char slave, char cmd, short word) 357 { 358 device_t parent = device_get_parent(dev); 359 int error, sent; 360 361 char low = (char)(word & 0xff); 362 char high = (char)((word & 0xff00) >> 8); 363 364 error = iicbus_start(parent, slave & ~LSB, 0); 365 366 if (!error) { 367 if (!(error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 368 if (!(error = iicbus_write(parent, &low, 1, &sent, IICBUS_TIMEOUT))) 369 error = iicbus_write(parent, &high, 1, &sent, IICBUS_TIMEOUT); 370 371 iicbus_stop(parent); 372 } 373 374 return (error); 375 } 376 377 static int 378 iicsmb_readb(device_t dev, u_char slave, char cmd, char *byte) 379 { 380 device_t parent = device_get_parent(dev); 381 int error, sent, read; 382 383 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 384 return (error); 385 386 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 387 goto error; 388 389 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 390 goto error; 391 392 if ((error = iicbus_read(parent, byte, 1, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) 393 goto error; 394 395 error: 396 iicbus_stop(parent); 397 return (error); 398 } 399 400 #define BUF2SHORT(low,high) \ 401 ((short)(((high) & 0xff) << 8) | (short)((low) & 0xff)) 402 403 static int 404 iicsmb_readw(device_t dev, u_char slave, char cmd, short *word) 405 { 406 device_t parent = device_get_parent(dev); 407 int error, sent, read; 408 char buf[2]; 409 410 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 411 return (error); 412 413 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 414 goto error; 415 416 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 417 goto error; 418 419 if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) 420 goto error; 421 422 /* first, receive low, then high byte */ 423 *word = BUF2SHORT(buf[0], buf[1]); 424 425 error: 426 iicbus_stop(parent); 427 return (error); 428 } 429 430 static int 431 iicsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata) 432 { 433 device_t parent = device_get_parent(dev); 434 int error, sent, read; 435 char buf[2]; 436 437 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 438 return (error); 439 440 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 441 goto error; 442 443 /* first, send low, then high byte */ 444 buf[0] = (char)(sdata & 0xff); 445 buf[1] = (char)((sdata & 0xff00) >> 8); 446 447 if ((error = iicbus_write(parent, buf, 2, &sent, IICBUS_TIMEOUT))) 448 goto error; 449 450 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 451 goto error; 452 453 if ((error = iicbus_read(parent, buf, 2, &read, IIC_LAST_READ, IICBUS_TIMEOUT))) 454 goto error; 455 456 /* first, receive low, then high byte */ 457 *rdata = BUF2SHORT(buf[0], buf[1]); 458 459 error: 460 iicbus_stop(parent); 461 return (error); 462 } 463 464 static int 465 iicsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf) 466 { 467 device_t parent = device_get_parent(dev); 468 int error, sent; 469 470 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 471 goto error; 472 473 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 474 goto error; 475 476 if ((error = iicbus_write(parent, buf, (int)count, &sent, IICBUS_TIMEOUT))) 477 goto error; 478 479 if ((error = iicbus_stop(parent))) 480 goto error; 481 482 error: 483 return (error); 484 } 485 486 static int 487 iicsmb_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf) 488 { 489 device_t parent = device_get_parent(dev); 490 int error, sent, read; 491 492 if ((error = iicbus_start(parent, slave & ~LSB, IICBUS_TIMEOUT))) 493 return (error); 494 495 if ((error = iicbus_write(parent, &cmd, 1, &sent, IICBUS_TIMEOUT))) 496 goto error; 497 498 if ((error = iicbus_repeated_start(parent, slave | LSB, IICBUS_TIMEOUT))) 499 goto error; 500 501 if ((error = iicbus_read(parent, buf, (int)*count, &read, 502 IIC_LAST_READ, IICBUS_TIMEOUT))) 503 goto error; 504 *count = read; 505 506 error: 507 iicbus_stop(parent); 508 return (error); 509 } 510 511 DRIVER_MODULE(iicsmb, iicbus, iicsmb_driver, iicsmb_devclass, 0, 0); 512 DRIVER_MODULE(smbus, iicsmb, smbus_driver, smbus_devclass, 0, 0); 513 MODULE_DEPEND(iicsmb, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); 514 MODULE_DEPEND(iicsmb, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER); 515 MODULE_VERSION(iicsmb, 1); 516