sys/bus/iicbus/iicsmb.c

   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);