arch/powerpc/cpu/mpc8xx/i2c.c

   1 /*
   2  * (C) Copyright 2000
   3  * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it
   4  *
   5  * (C) Copyright 2000 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   6  * Marius Groeger <mgroeger@sysgo.de>
   7  *
   8  * See file CREDITS for list of people who contributed to this
   9  * project.
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License as
  13  * published by the Free Software Foundation; either version 2 of
  14  * the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  24  * MA 02111-1307 USA
  25  *
  26  * Back ported to the 8xx platform (from the 8260 platform) by
  27  * Murray.Jensen@cmst.csiro.au, 27-Jan-01.
  28  */
  29
  30 #include <common.h>
  31
  32 #ifdef CONFIG_HARD_I2C
  33
  34 #include <commproc.h>
  35 #include <i2c.h>
  36 #ifdef CONFIG_LWMON
  37 #include <watchdog.h>
  38 #endif
  39
  40 DECLARE_GLOBAL_DATA_PTR;
  41
  42 /* define to enable debug messages */
  43 #undef  DEBUG_I2C
  44
  45 /* tx/rx timeout (we need the i2c early, so we don't use get_timer()) */
  46 #define TOUT_LOOP 1000000
  47
  48 #define NUM_RX_BDS 4
  49 #define NUM_TX_BDS 4
  50 #define MAX_TX_SPACE 256
  51 #define I2C_RXTX_LEN 128        /* maximum tx/rx buffer length */
  52
  53 typedef struct I2C_BD {
  54         unsigned short status;
  55         unsigned short length;
  56         unsigned char *addr;
  57 } I2C_BD;
  58
  59 #define BD_I2C_TX_START 0x0400  /* special status for i2c: Start condition */
  60
  61 #define BD_I2C_TX_CL    0x0001  /* collision error */
  62 #define BD_I2C_TX_UN    0x0002  /* underflow error */
  63 #define BD_I2C_TX_NAK   0x0004  /* no acknowledge error */
  64 #define BD_I2C_TX_ERR   (BD_I2C_TX_NAK|BD_I2C_TX_UN|BD_I2C_TX_CL)
  65
  66 #define BD_I2C_RX_ERR   BD_SC_OV
  67
  68 typedef void (*i2c_ecb_t) (int, int);   /* error callback function */
  69
  70 /* This structure keeps track of the bd and buffer space usage. */
  71 typedef struct i2c_state {
  72         int rx_idx;             /* index   to next free Rx BD */
  73         int tx_idx;             /* index   to next free Tx BD */
  74         void *rxbd;             /* pointer to next free Rx BD */
  75         void *txbd;             /* pointer to next free Tx BD */
  76         int tx_space;           /* number  of Tx bytes left   */
  77         unsigned char *tx_buf;  /* pointer to free Tx area    */
  78         i2c_ecb_t err_cb;       /* error callback function    */
  79 } i2c_state_t;
  80
  81
  82 /* flags for i2c_send() and i2c_receive() */
  83 #define I2CF_ENABLE_SECONDARY   0x01  /* secondary_address is valid           */
  84 #define I2CF_START_COND         0x02  /* tx: generate start condition         */
  85 #define I2CF_STOP_COND          0x04  /* tx: generate stop  condition         */
  86
  87 /* return codes */
  88 #define I2CERR_NO_BUFFERS       0x01  /* no more BDs or buffer space          */
  89 #define I2CERR_MSG_TOO_LONG     0x02  /* tried to send/receive to much data   */
  90 #define I2CERR_TIMEOUT          0x03  /* timeout in i2c_doio()                */
  91 #define I2CERR_QUEUE_EMPTY      0x04  /* i2c_doio called without send/receive */
  92
  93 /* error callback flags */
  94 #define I2CECB_RX_ERR           0x10  /* this is a receive error              */
  95 #define     I2CECB_RX_ERR_OV    0x02  /* receive overrun error                */
  96 #define     I2CECB_RX_MASK      0x0f  /* mask for error bits                  */
  97 #define I2CECB_TX_ERR           0x20  /* this is a transmit error             */
  98 #define     I2CECB_TX_CL        0x01  /* transmit collision error             */
  99 #define     I2CECB_TX_UN        0x02  /* transmit underflow error             */
 100 #define     I2CECB_TX_NAK       0x04  /* transmit no ack error                */
 101 #define     I2CECB_TX_MASK      0x0f  /* mask for error bits                  */
 102 #define I2CECB_TIMEOUT          0x40  /* this is a timeout error              */
 103
 104 #ifdef DEBUG_I2C
 105 #define PRINTD(x) printf x
 106 #else
 107 #define PRINTD(x)
 108 #endif
 109
 110 /*
 111  * Returns the best value of I2BRG to meet desired clock speed of I2C with
 112  * input parameters (clock speed, filter, and predivider value).
 113  * It returns computer speed value and the difference between it and desired
 114  * speed.
 115  */
 116 static inline int
 117 i2c_roundrate(int hz, int speed, int filter, int modval,
 118               int *brgval, int *totspeed)
 119 {
 120         int moddiv = 1 << (5 - (modval & 3)), brgdiv, div;
 121
 122         PRINTD(("\t[I2C] trying hz=%d, speed=%d, filter=%d, modval=%d\n",
 123                 hz, speed, filter, modval));
 124
 125         div = moddiv * speed;
 126         brgdiv = (hz + div - 1) / div;
 127
 128         PRINTD(("\t\tmoddiv=%d, brgdiv=%d\n", moddiv, brgdiv));
 129
 130         *brgval = ((brgdiv + 1) / 2) - 3 - (2 * filter);
 131
 132         if ((*brgval < 0) || (*brgval > 255)) {
 133                 PRINTD(("\t\trejected brgval=%d\n", *brgval));
 134                 return -1;
 135         }
 136
 137         brgdiv = 2 * (*brgval + 3 + (2 * filter));
 138         div = moddiv * brgdiv;
 139         *totspeed = hz / div;
 140
 141         PRINTD(("\t\taccepted brgval=%d, totspeed=%d\n", *brgval, *totspeed));
 142
 143         return 0;
 144 }
 145
 146 /*
 147  * Sets the I2C clock predivider and divider to meet required clock speed.
 148  */
 149 static int i2c_setrate(int hz, int speed)
 150 {
 151         immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 152         volatile i2c8xx_t *i2c = (i2c8xx_t *) & immap->im_i2c;
 153         int     brgval,
 154                 modval, /* 0-3 */
 155                 bestspeed_diff = speed,
 156                 bestspeed_brgval = 0,
 157                 bestspeed_modval = 0,
 158                 bestspeed_filter = 0,
 159                 totspeed,
 160                 filter = 0;     /* Use this fixed value */
 161
 162         for (modval = 0; modval < 4; modval++) {
 163                 if (i2c_roundrate
 164                     (hz, speed, filter, modval, &brgval, &totspeed) == 0) {
 165                         int diff = speed - totspeed;
 166
 167                         if ((diff >= 0) && (diff < bestspeed_diff)) {
 168                                 bestspeed_diff = diff;
 169                                 bestspeed_modval = modval;
 170                                 bestspeed_brgval = brgval;
 171                                 bestspeed_filter = filter;
 172                         }
 173                 }
 174         }
 175
 176         PRINTD (("[I2C] Best is:\n"));
 177         PRINTD (("[I2C] CPU=%dhz RATE=%d F=%d I2MOD=%08x I2BRG=%08x DIFF=%dhz\n",
 178                 hz,
 179                 speed,
 180                 bestspeed_filter,
 181                 bestspeed_modval,
 182                 bestspeed_brgval,
 183                 bestspeed_diff));
 184
 185         i2c->i2c_i2mod |=
 186                 ((bestspeed_modval & 3) << 1) | (bestspeed_filter << 3);
 187         i2c->i2c_i2brg = bestspeed_brgval & 0xff;
 188
 189         PRINTD (("[I2C] i2mod=%08x i2brg=%08x\n", i2c->i2c_i2mod,
 190                 i2c->i2c_i2brg));
 191
 192         return 1;
 193 }
 194
 195 void i2c_init(int speed, int slaveaddr)
 196 {
 197         volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR;
 198         volatile cpm8xx_t *cp = (cpm8xx_t *)&immap->im_cpm;
 199         volatile i2c8xx_t *i2c = (i2c8xx_t *)&immap->im_i2c;
 200         volatile iic_t *iip = (iic_t *)&cp->cp_dparam[PROFF_IIC];
 201         ulong rbase, tbase;
 202         volatile I2C_BD *rxbd, *txbd;
 203         uint dpaddr;
 204
 205 #ifdef CONFIG_SYS_I2C_INIT_BOARD
 206         /* call board specific i2c bus reset routine before accessing the   */
 207         /* environment, which might be in a chip on that bus. For details   */
 208         /* about this problem see doc/I2C_Edge_Conditions.                  */
 209         i2c_init_board();
 210 #endif
 211
 212 #ifdef CONFIG_SYS_I2C_UCODE_PATCH
 213         iip = (iic_t *)&cp->cp_dpmem[iip->iic_rpbase];
 214 #else
 215         /* Disable relocation */
 216         iip->iic_rpbase = 0;
 217 #endif
 218
 219 #ifdef CONFIG_SYS_ALLOC_DPRAM
 220         dpaddr = iip->iic_rbase;
 221         if (dpaddr == 0) {
 222                 /* need to allocate dual port ram */
 223                 dpaddr = dpram_alloc_align((NUM_RX_BDS * sizeof(I2C_BD)) +
 224                                            (NUM_TX_BDS * sizeof(I2C_BD)) +
 225                                            MAX_TX_SPACE, 8);
 226         }
 227 #else
 228         dpaddr = CPM_I2C_BASE;
 229 #endif
 230
 231         /*
 232          * initialise data in dual port ram:
 233          *
 234          * dpaddr->rbase -> rx BD         (NUM_RX_BDS * sizeof(I2C_BD) bytes)
 235          *         tbase -> tx BD         (NUM_TX_BDS * sizeof(I2C_BD) bytes)
 236          *                  tx buffer     (MAX_TX_SPACE bytes)
 237          */
 238
 239         rbase = dpaddr;
 240         tbase = rbase + NUM_RX_BDS * sizeof(I2C_BD);
 241
 242         /* Initialize Port B I2C pins. */
 243         cp->cp_pbpar |= 0x00000030;
 244         cp->cp_pbdir |= 0x00000030;
 245         cp->cp_pbodr |= 0x00000030;
 246
 247         /* Disable interrupts */
 248         i2c->i2c_i2mod = 0x00;
 249         i2c->i2c_i2cmr = 0x00;
 250         i2c->i2c_i2cer = 0xff;
 251         i2c->i2c_i2add = slaveaddr;
 252
 253         /*
 254          * Set the I2C BRG Clock division factor from desired i2c rate
 255          * and current CPU rate (we assume sccr dfbgr field is 0;
 256          * divide BRGCLK by 1)
 257          */
 258         PRINTD(("[I2C] Setting rate...\n"));
 259         i2c_setrate(gd->cpu_clk, CONFIG_SYS_I2C_SPEED);
 260
 261         /* Set I2C controller in master mode */
 262         i2c->i2c_i2com = 0x01;
 263
 264         /* Set SDMA bus arbitration level to 5 (SDCR) */
 265         immap->im_siu_conf.sc_sdcr = 0x0001;
 266
 267         /* Initialize Tx/Rx parameters */
 268         iip->iic_rbase = rbase;
 269         iip->iic_tbase = tbase;
 270         rxbd = (I2C_BD *) ((unsigned char *) &cp->cp_dpmem[iip->iic_rbase]);
 271         txbd = (I2C_BD *) ((unsigned char *) &cp->cp_dpmem[iip->iic_tbase]);
 272
 273         PRINTD(("[I2C] rbase = %04x\n", iip->iic_rbase));
 274         PRINTD(("[I2C] tbase = %04x\n", iip->iic_tbase));
 275         PRINTD(("[I2C] rxbd = %08x\n", (int)rxbd));
 276         PRINTD(("[I2C] txbd = %08x\n", (int)txbd));
 277
 278         /* Set big endian byte order */
 279         iip->iic_tfcr = 0x10;
 280         iip->iic_rfcr = 0x10;
 281
 282         /* Set maximum receive size. */
 283         iip->iic_mrblr = I2C_RXTX_LEN;
 284
 285 #ifdef CONFIG_SYS_I2C_UCODE_PATCH
 286         /*
 287          *  Initialize required parameters if using microcode patch.
 288          */
 289         iip->iic_rbptr = iip->iic_rbase;
 290         iip->iic_tbptr = iip->iic_tbase;
 291         iip->iic_rstate = 0;
 292         iip->iic_tstate = 0;
 293 #else
 294         cp->cp_cpcr = mk_cr_cmd(CPM_CR_CH_I2C, CPM_CR_INIT_TRX) | CPM_CR_FLG;
 295         do {
 296                 __asm__ __volatile__("eieio");
 297         } while (cp->cp_cpcr & CPM_CR_FLG);
 298 #endif
 299
 300         /* Clear events and interrupts */
 301         i2c->i2c_i2cer = 0xff;
 302         i2c->i2c_i2cmr = 0x00;
 303 }
 304
 305 static void i2c_newio(i2c_state_t *state)
 306 {
 307         volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
 308         volatile cpm8xx_t *cp = (cpm8xx_t *)&immap->im_cpm;
 309         volatile iic_t *iip = (iic_t *)&cp->cp_dparam[PROFF_IIC];
 310
 311         PRINTD(("[I2C] i2c_newio\n"));
 312
 313 #ifdef CONFIG_SYS_I2C_UCODE_PATCH
 314         iip = (iic_t *)&cp->cp_dpmem[iip->iic_rpbase];
 315 #endif
 316         state->rx_idx = 0;
 317         state->tx_idx = 0;
 318         state->rxbd = (void *)&cp->cp_dpmem[iip->iic_rbase];
 319         state->txbd = (void *)&cp->cp_dpmem[iip->iic_tbase];
 320         state->tx_space = MAX_TX_SPACE;
 321         state->tx_buf = (uchar *)state->txbd + NUM_TX_BDS * sizeof(I2C_BD);
 322         state->err_cb = NULL;
 323
 324         PRINTD(("[I2C] rxbd = %08x\n", (int)state->rxbd));
 325         PRINTD(("[I2C] txbd = %08x\n", (int)state->txbd));
 326         PRINTD(("[I2C] tx_buf = %08x\n", (int)state->tx_buf));
 327
 328         /* clear the buffer memory */
 329         memset((char *)state->tx_buf, 0, MAX_TX_SPACE);
 330 }
 331
 332 static int
 333 i2c_send(i2c_state_t *state,
 334          unsigned char address,
 335          unsigned char secondary_address,
 336          unsigned int flags, unsigned short size, unsigned char *dataout)
 337 {
 338         volatile I2C_BD *txbd;
 339         int i, j;
 340
 341         PRINTD(("[I2C] i2c_send add=%02d sec=%02d flag=%02d size=%d\n",
 342                 address, secondary_address, flags, size));
 343
 344         /* trying to send message larger than BD */
 345         if (size > I2C_RXTX_LEN)
 346                 return I2CERR_MSG_TOO_LONG;
 347
 348         /* no more free bds */
 349         if (state->tx_idx >= NUM_TX_BDS || state->tx_space < (2 + size))
 350                 return I2CERR_NO_BUFFERS;
 351
 352         txbd = (I2C_BD *) state->txbd;
 353         txbd->addr = state->tx_buf;
 354
 355         PRINTD(("[I2C] txbd = %08x\n", (int)txbd));
 356
 357         if (flags & I2CF_START_COND) {
 358                 PRINTD(("[I2C] Formatting addresses...\n"));
 359                 if (flags & I2CF_ENABLE_SECONDARY) {
 360                         /* Length of msg + dest addr */
 361                         txbd->length = size + 2;
 362
 363                         txbd->addr[0] = address << 1;
 364                         txbd->addr[1] = secondary_address;
 365                         i = 2;
 366                 } else {
 367                         /* Length of msg + dest addr */
 368                         txbd->length = size + 1;
 369                         /* Write dest addr to BD */
 370                         txbd->addr[0] = address << 1;
 371                         i = 1;
 372                 }
 373         } else {
 374                 txbd->length = size;    /* Length of message */
 375                 i = 0;
 376         }
 377
 378         /* set up txbd */
 379         txbd->status = BD_SC_READY;
 380         if (flags & I2CF_START_COND)
 381                 txbd->status |= BD_I2C_TX_START;
 382         if (flags & I2CF_STOP_COND)
 383                 txbd->status |= BD_SC_LAST | BD_SC_WRAP;
 384
 385         /* Copy data to send into buffer */
 386         PRINTD(("[I2C] copy data...\n"));
 387         for(j = 0; j < size; i++, j++)
 388                 txbd->addr[i] = dataout[j];
 389
 390         PRINTD(("[I2C] txbd: length=0x%04x status=0x%04x addr[0]=0x%02x addr[1]=0x%02x\n",
 391                 txbd->length,
 392                 txbd->status,
 393                 txbd->addr[0],
 394                 txbd->addr[1]));
 395
 396         /* advance state */
 397         state->tx_buf += txbd->length;
 398         state->tx_space -= txbd->length;
 399         state->tx_idx++;
 400         state->txbd = (void *) (txbd + 1);
 401
 402         return 0;
 403 }
 404
 405 static int
 406 i2c_receive(i2c_state_t *state,
 407             unsigned char address,
 408             unsigned char secondary_address,
 409             unsigned int flags,
 410             unsigned short size_to_expect, unsigned char *datain)
 411 {
 412         volatile I2C_BD *rxbd, *txbd;
 413
 414         PRINTD(("[I2C] i2c_receive %02d %02d %02d\n",
 415                 address, secondary_address, flags));
 416
 417         /* Expected to receive too much */
 418         if (size_to_expect > I2C_RXTX_LEN)
 419                 return I2CERR_MSG_TOO_LONG;
 420
 421         /* no more free bds */
 422         if (state->tx_idx >= NUM_TX_BDS || state->rx_idx >= NUM_RX_BDS
 423             || state->tx_space < 2)
 424                 return I2CERR_NO_BUFFERS;
 425
 426         rxbd = (I2C_BD *) state->rxbd;
 427         txbd = (I2C_BD *) state->txbd;
 428
 429         PRINTD(("[I2C] rxbd = %08x\n", (int)rxbd));
 430         PRINTD(("[I2C] txbd = %08x\n", (int)txbd));
 431
 432         txbd->addr = state->tx_buf;
 433
 434         /* set up TXBD for destination address */
 435         if (flags & I2CF_ENABLE_SECONDARY) {
 436                 txbd->length = 2;
 437                 txbd->addr[0] = address << 1;   /* Write data */
 438                 txbd->addr[1] = secondary_address;      /* Internal address */
 439                 txbd->status = BD_SC_READY;
 440         } else {
 441                 txbd->length = 1 + size_to_expect;
 442                 txbd->addr[0] = (address << 1) | 0x01;
 443                 txbd->status = BD_SC_READY;
 444                 memset(&txbd->addr[1], 0, txbd->length);
 445         }
 446
 447         /* set up rxbd for reception */
 448         rxbd->status = BD_SC_EMPTY;
 449         rxbd->length = size_to_expect;
 450         rxbd->addr = datain;
 451
 452         txbd->status |= BD_I2C_TX_START;
 453         if (flags & I2CF_STOP_COND) {
 454                 txbd->status |= BD_SC_LAST | BD_SC_WRAP;
 455                 rxbd->status |= BD_SC_WRAP;
 456         }
 457
 458         PRINTD(("[I2C] txbd: length=0x%04x status=0x%04x addr[0]=0x%02x addr[1]=0x%02x\n",
 459                 txbd->length,
 460                 txbd->status,
 461                 txbd->addr[0],
 462                 txbd->addr[1]));
 463         PRINTD(("[I2C] rxbd: length=0x%04x status=0x%04x addr[0]=0x%02x addr[1]=0x%02x\n",
 464                 rxbd->length,
 465                 rxbd->status,
 466                 rxbd->addr[0],
 467                 rxbd->addr[1]));
 468
 469         /* advance state */
 470         state->tx_buf += txbd->length;
 471         state->tx_space -= txbd->length;
 472         state->tx_idx++;
 473         state->txbd = (void *) (txbd + 1);
 474         state->rx_idx++;
 475         state->rxbd = (void *) (rxbd + 1);
 476
 477         return 0;
 478 }
 479
 480
 481 static int i2c_doio(i2c_state_t *state)
 482 {
 483         volatile immap_t *immap = (immap_t *)CONFIG_SYS_IMMR;
 484         volatile cpm8xx_t *cp = (cpm8xx_t *)&immap->im_cpm;
 485         volatile i2c8xx_t *i2c = (i2c8xx_t *)&immap->im_i2c;
 486         volatile iic_t *iip = (iic_t *)&cp->cp_dparam[PROFF_IIC];
 487         volatile I2C_BD *txbd, *rxbd;
 488         volatile int j = 0;
 489
 490         PRINTD(("[I2C] i2c_doio\n"));
 491
 492 #ifdef CONFIG_SYS_I2C_UCODE_PATCH
 493         iip = (iic_t *)&cp->cp_dpmem[iip->iic_rpbase];
 494 #endif
 495
 496         if (state->tx_idx <= 0 && state->rx_idx <= 0) {
 497                 PRINTD(("[I2C] No I/O is queued\n"));
 498                 return I2CERR_QUEUE_EMPTY;
 499         }
 500
 501         iip->iic_rbptr = iip->iic_rbase;
 502         iip->iic_tbptr = iip->iic_tbase;
 503
 504         /* Enable I2C */
 505         PRINTD(("[I2C] Enabling I2C...\n"));
 506         i2c->i2c_i2mod |= 0x01;
 507
 508         /* Begin transmission */
 509         i2c->i2c_i2com |= 0x80;
 510
 511         /* Loop until transmit & receive completed */
 512
 513         if (state->tx_idx > 0) {
 514                 txbd = ((I2C_BD*)state->txbd) - 1;
 515                 PRINTD(("[I2C] Transmitting...(txbd=0x%08lx)\n", (ulong)txbd));
 516                 while ((txbd->status & BD_SC_READY) && (j++ < TOUT_LOOP)) {
 517                         if (ctrlc())
 518                                 return (-1);
 519
 520                         __asm__ __volatile__("eieio");
 521                 }
 522         }
 523
 524         if ((state->rx_idx > 0) && (j < TOUT_LOOP)) {
 525                 rxbd = ((I2C_BD*)state->rxbd) - 1;
 526                 PRINTD(("[I2C] Receiving...(rxbd=0x%08lx)\n", (ulong)rxbd));
 527                 while ((rxbd->status & BD_SC_EMPTY) && (j++ < TOUT_LOOP)) {
 528                         if (ctrlc())
 529                                 return (-1);
 530
 531                         __asm__ __volatile__("eieio");
 532                 }
 533         }
 534
 535         /* Turn off I2C */
 536         i2c->i2c_i2mod &= ~0x01;
 537
 538         if (state->err_cb != NULL) {
 539                 int n, i, b;
 540
 541                 /*
 542                  * if we have an error callback function, look at the
 543                  * error bits in the bd status and pass them back
 544                  */
 545
 546                 if ((n = state->tx_idx) > 0) {
 547                         for (i = 0; i < n; i++) {
 548                                 txbd = ((I2C_BD *) state->txbd) - (n - i);
 549                                 if ((b = txbd->status & BD_I2C_TX_ERR) != 0)
 550                                         (*state->err_cb) (I2CECB_TX_ERR | b,
 551                                                           i);
 552                         }
 553                 }
 554
 555                 if ((n = state->rx_idx) > 0) {
 556                         for (i = 0; i < n; i++) {
 557                                 rxbd = ((I2C_BD *) state->rxbd) - (n - i);
 558                                 if ((b = rxbd->status & BD_I2C_RX_ERR) != 0)
 559                                         (*state->err_cb) (I2CECB_RX_ERR | b,
 560                                                           i);
 561                         }
 562                 }
 563
 564                 if (j >= TOUT_LOOP)
 565                         (*state->err_cb) (I2CECB_TIMEOUT, 0);
 566         }
 567
 568         return (j >= TOUT_LOOP) ? I2CERR_TIMEOUT : 0;
 569 }
 570
 571 static int had_tx_nak;
 572
 573 static void i2c_test_callback(int flags, int xnum)
 574 {
 575         if ((flags & I2CECB_TX_ERR) && (flags & I2CECB_TX_NAK))
 576                 had_tx_nak = 1;
 577 }
 578
 579 int i2c_probe(uchar chip)
 580 {
 581         i2c_state_t state;
 582         int rc;
 583         uchar buf[1];
 584
 585         i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
 586
 587         i2c_newio(&state);
 588
 589         state.err_cb = i2c_test_callback;
 590         had_tx_nak = 0;
 591
 592         rc = i2c_receive(&state, chip, 0, I2CF_START_COND | I2CF_STOP_COND, 1,
 593                          buf);
 594
 595         if (rc != 0)
 596                 return (rc);
 597
 598         rc = i2c_doio(&state);
 599
 600         if ((rc != 0) && (rc != I2CERR_TIMEOUT))
 601                 return (rc);
 602
 603         return (had_tx_nak);
 604 }
 605
 606 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
 607 {
 608         i2c_state_t state;
 609         uchar xaddr[4];
 610         int rc;
 611
 612 #ifdef CONFIG_LWMON
 613         WATCHDOG_RESET();
 614 #endif
 615
 616         xaddr[0] = (addr >> 24) & 0xFF;
 617         xaddr[1] = (addr >> 16) & 0xFF;
 618         xaddr[2] = (addr >> 8) & 0xFF;
 619         xaddr[3] = addr & 0xFF;
 620
 621 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
 622         /*
 623          * EEPROM chips that implement "address overflow" are ones like
 624          * Catalyst 24WC04/08/16 which has 9/10/11 bits of address and the
 625          * extra bits end up in the "chip address" bit slots.  This makes
 626          * a 24WC08 (1Kbyte) chip look like four 256 byte chips.
 627          *
 628          * Note that we consider the length of the address field to still
 629          * be one byte because the extra address bits are hidden in the
 630          * chip address.
 631          */
 632         chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
 633 #endif
 634
 635         i2c_newio(&state);
 636
 637         rc = i2c_send(&state, chip, 0, I2CF_START_COND, alen,
 638                       &xaddr[4 - alen]);
 639         if (rc != 0) {
 640                 printf("i2c_read: i2c_send failed (%d)\n", rc);
 641                 return 1;
 642         }
 643
 644         rc = i2c_receive(&state, chip, 0, I2CF_STOP_COND, len, buffer);
 645         if (rc != 0) {
 646                 printf("i2c_read: i2c_receive failed (%d)\n", rc);
 647                 return 1;
 648         }
 649
 650         rc = i2c_doio(&state);
 651         if (rc != 0) {
 652                 printf("i2c_read: i2c_doio failed (%d)\n", rc);
 653                 return 1;
 654         }
 655         return 0;
 656 }
 657
 658 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
 659 {
 660         i2c_state_t state;
 661         uchar xaddr[4];
 662         int rc;
 663
 664         xaddr[0] = (addr >> 24) & 0xFF;
 665         xaddr[1] = (addr >> 16) & 0xFF;
 666         xaddr[2] = (addr >> 8) & 0xFF;
 667         xaddr[3] = addr & 0xFF;
 668
 669 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
 670         /*
 671          * EEPROM chips that implement "address overflow" are ones like
 672          * Catalyst 24WC04/08/16 which has 9/10/11 bits of address and the
 673          * extra bits end up in the "chip address" bit slots.  This makes
 674          * a 24WC08 (1Kbyte) chip look like four 256 byte chips.
 675          *
 676          * Note that we consider the length of the address field to still
 677          * be one byte because the extra address bits are hidden in the
 678          * chip address.
 679          */
 680         chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
 681 #endif
 682
 683         i2c_newio(&state);
 684
 685         rc = i2c_send(&state, chip, 0, I2CF_START_COND, alen,
 686                       &xaddr[4 - alen]);
 687         if (rc != 0) {
 688                 printf("i2c_write: first i2c_send failed (%d)\n", rc);
 689                 return 1;
 690         }
 691
 692         rc = i2c_send(&state, 0, 0, I2CF_STOP_COND, len, buffer);
 693         if (rc != 0) {
 694                 printf("i2c_write: second i2c_send failed (%d)\n", rc);
 695                 return 1;
 696         }
 697
 698         rc = i2c_doio(&state);
 699         if (rc != 0) {
 700                 printf("i2c_write: i2c_doio failed (%d)\n", rc);
 701                 return 1;
 702         }
 703         return 0;
 704 }
 705
 706 #endif /* CONFIG_HARD_I2C */