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