git.sur5r.net Git - u-boot/blob - drivers/i2c/omap24xx_i2c.c

   1 /*
   2  * Basic I2C functions
   3  *
   4  * Copyright (c) 2004 Texas Instruments
   5  *
   6  * This package is free software;  you can redistribute it and/or
   7  * modify it under the terms of the license found in the file
   8  * named COPYING that should have accompanied this file.
   9  *
  10  * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  11  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  12  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  13  *
  14  * Author: Jian Zhang jzhang@ti.com, Texas Instruments
  15  *
  16  * Copyright (c) 2003 Wolfgang Denk, wd@denx.de
  17  * Rewritten to fit into the current U-Boot framework
  18  *
  19  * Adapted for OMAP2420 I2C, r-woodruff2@ti.com
  20  *
  21  * Copyright (c) 2013 Lubomir Popov <lpopov@mm-sol.com>, MM Solutions
  22  * New i2c_read, i2c_write and i2c_probe functions, tested on OMAP4
  23  * (4430/60/70), OMAP5 (5430) and AM335X (3359); should work on older
  24  * OMAPs and derivatives as well. The only anticipated exception would
  25  * be the OMAP2420, which shall require driver modification.
  26  * - Rewritten i2c_read to operate correctly with all types of chips
  27  *   (old function could not read consistent data from some I2C slaves).
  28  * - Optimized i2c_write.
  29  * - New i2c_probe, performs write access vs read. The old probe could
  30  *   hang the system under certain conditions (e.g. unconfigured pads).
  31  * - The read/write/probe functions try to identify unconfigured bus.
  32  * - Status functions now read irqstatus_raw as per TRM guidelines
  33  *   (except for OMAP243X and OMAP34XX).
  34  * - Driver now supports up to I2C5 (OMAP5).
  35  *
  36  * Copyright (c) 2014 Hannes Schmelzer <oe5hpm@oevsv.at>, B&R
  37  * - Added support for set_speed
  38  *
  39  */
  40
  41 #include <common.h>
  42 #include <i2c.h>
  43
  44 #include <asm/arch/i2c.h>
  45 #include <asm/io.h>
  46
  47 #include "omap24xx_i2c.h"
  48
  49 DECLARE_GLOBAL_DATA_PTR;
  50
  51 #define I2C_TIMEOUT     1000
  52
  53 /* Absolutely safe for status update at 100 kHz I2C: */
  54 #define I2C_WAIT        200
  55
  56 static int wait_for_bb(struct i2c_adapter *adap);
  57 static struct i2c *omap24_get_base(struct i2c_adapter *adap);
  58 static u16 wait_for_event(struct i2c_adapter *adap);
  59 static void flush_fifo(struct i2c_adapter *adap);
  60 static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
  61 {
  62         unsigned int sampleclk, prescaler;
  63         int fsscll, fssclh;
  64
  65         speed <<= 1;
  66         prescaler = 0;
  67         /*
  68          * some divisors may cause a precission loss, but shouldn't
  69          * be a big thing, because i2c_clk is then allready very slow.
  70          */
  71         while (prescaler <= 0xFF) {
  72                 sampleclk = I2C_IP_CLK / (prescaler+1);
  73
  74                 fsscll = sampleclk / speed;
  75                 fssclh = fsscll;
  76                 fsscll -= I2C_FASTSPEED_SCLL_TRIM;
  77                 fssclh -= I2C_FASTSPEED_SCLH_TRIM;
  78
  79                 if (((fsscll > 0) && (fssclh > 0)) &&
  80                     ((fsscll <= (255-I2C_FASTSPEED_SCLL_TRIM)) &&
  81                     (fssclh <= (255-I2C_FASTSPEED_SCLH_TRIM)))) {
  82                         if (pscl)
  83                                 *pscl = fsscll;
  84                         if (psch)
  85                                 *psch = fssclh;
  86
  87                         return prescaler;
  88                 }
  89                 prescaler++;
  90         }
  91         return -1;
  92 }
  93 static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
  94 {
  95         struct i2c *i2c_base = omap24_get_base(adap);
  96         int psc, fsscll = 0, fssclh = 0;
  97         int hsscll = 0, hssclh = 0;
  98         u32 scll = 0, sclh = 0;
  99
 100         if (speed >= OMAP_I2C_HIGH_SPEED) {
 101                 /* High speed */
 102                 psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK;
 103                 psc -= 1;
 104                 if (psc < I2C_PSC_MIN) {
 105                         printf("Error : I2C unsupported prescaler %d\n", psc);
 106                         return -1;
 107                 }
 108
 109                 /* For first phase of HS mode */
 110                 fsscll = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
 111
 112                 fssclh = fsscll;
 113
 114                 fsscll -= I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM;
 115                 fssclh -= I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM;
 116                 if (((fsscll < 0) || (fssclh < 0)) ||
 117                     ((fsscll > 255) || (fssclh > 255))) {
 118                         puts("Error : I2C initializing first phase clock\n");
 119                         return -1;
 120                 }
 121
 122                 /* For second phase of HS mode */
 123                 hsscll = hssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
 124
 125                 hsscll -= I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM;
 126                 hssclh -= I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM;
 127                 if (((fsscll < 0) || (fssclh < 0)) ||
 128                     ((fsscll > 255) || (fssclh > 255))) {
 129                         puts("Error : I2C initializing second phase clock\n");
 130                         return -1;
 131                 }
 132
 133                 scll = (unsigned int)hsscll << 8 | (unsigned int)fsscll;
 134                 sclh = (unsigned int)hssclh << 8 | (unsigned int)fssclh;
 135
 136         } else {
 137                 /* Standard and fast speed */
 138                 psc = omap24_i2c_findpsc(&scll, &sclh, speed);
 139                 if (0 > psc) {
 140                         puts("Error : I2C initializing clock\n");
 141                         return -1;
 142                 }
 143         }
 144
 145         adap->speed     = speed;
 146         adap->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */
 147         writew(0, &i2c_base->con);
 148         writew(psc, &i2c_base->psc);
 149         writew(scll, &i2c_base->scll);
 150         writew(sclh, &i2c_base->sclh);
 151         writew(I2C_CON_EN, &i2c_base->con);
 152         writew(0xFFFF, &i2c_base->stat);        /* clear all pending status */
 153
 154         return 0;
 155 }
 156
 157 static void omap24_i2c_deblock(struct i2c_adapter *adap)
 158 {
 159         struct i2c *i2c_base = omap24_get_base(adap);
 160         int i;
 161         u16 systest;
 162         u16 orgsystest;
 163
 164         /* set test mode ST_EN = 1 */
 165         orgsystest = readw(&i2c_base->systest);
 166         systest = orgsystest;
 167         /* enable testmode */
 168         systest |= I2C_SYSTEST_ST_EN;
 169         writew(systest, &i2c_base->systest);
 170         systest &= ~I2C_SYSTEST_TMODE_MASK;
 171         systest |= 3 << I2C_SYSTEST_TMODE_SHIFT;
 172         writew(systest, &i2c_base->systest);
 173
 174         /* set SCL, SDA  = 1 */
 175         systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
 176         writew(systest, &i2c_base->systest);
 177         udelay(10);
 178
 179         /* toggle scl 9 clocks */
 180         for (i = 0; i < 9; i++) {
 181                 /* SCL = 0 */
 182                 systest &= ~I2C_SYSTEST_SCL_O;
 183                 writew(systest, &i2c_base->systest);
 184                 udelay(10);
 185                 /* SCL = 1 */
 186                 systest |= I2C_SYSTEST_SCL_O;
 187                 writew(systest, &i2c_base->systest);
 188                 udelay(10);
 189         }
 190
 191         /* send stop */
 192         systest &= ~I2C_SYSTEST_SDA_O;
 193         writew(systest, &i2c_base->systest);
 194         udelay(10);
 195         systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
 196         writew(systest, &i2c_base->systest);
 197         udelay(10);
 198
 199         /* restore original mode */
 200         writew(orgsystest, &i2c_base->systest);
 201 }
 202
 203 static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
 204 {
 205         struct i2c *i2c_base = omap24_get_base(adap);
 206         int timeout = I2C_TIMEOUT;
 207         int deblock = 1;
 208
 209 retry:
 210         if (readw(&i2c_base->con) & I2C_CON_EN) {
 211                 writew(0, &i2c_base->con);
 212                 udelay(50000);
 213         }
 214
 215         writew(0x2, &i2c_base->sysc); /* for ES2 after soft reset */
 216         udelay(1000);
 217
 218         writew(I2C_CON_EN, &i2c_base->con);
 219         while (!(readw(&i2c_base->syss) & I2C_SYSS_RDONE) && timeout--) {
 220                 if (timeout <= 0) {
 221                         puts("ERROR: Timeout in soft-reset\n");
 222                         return;
 223                 }
 224                 udelay(1000);
 225         }
 226
 227         if (0 != omap24_i2c_setspeed(adap, speed)) {
 228                 printf("ERROR: failed to setup I2C bus-speed!\n");
 229                 return;
 230         }
 231
 232         /* own address */
 233         writew(slaveadd, &i2c_base->oa);
 234
 235 #if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
 236         /*
 237          * Have to enable interrupts for OMAP2/3, these IPs don't have
 238          * an 'irqstatus_raw' register and we shall have to poll 'stat'
 239          */
 240         writew(I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
 241                I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
 242 #endif
 243         udelay(1000);
 244         flush_fifo(adap);
 245         writew(0xFFFF, &i2c_base->stat);
 246
 247         /* Handle possible failed I2C state */
 248         if (wait_for_bb(adap))
 249                 if (deblock == 1) {
 250                         omap24_i2c_deblock(adap);
 251                         deblock = 0;
 252                         goto retry;
 253                 }
 254 }
 255
 256 static void flush_fifo(struct i2c_adapter *adap)
 257 {
 258         struct i2c *i2c_base = omap24_get_base(adap);
 259         u16 stat;
 260
 261         /*
 262          * note: if you try and read data when its not there or ready
 263          * you get a bus error
 264          */
 265         while (1) {
 266                 stat = readw(&i2c_base->stat);
 267                 if (stat == I2C_STAT_RRDY) {
 268                         readb(&i2c_base->data);
 269                         writew(I2C_STAT_RRDY, &i2c_base->stat);
 270                         udelay(1000);
 271                 } else
 272                         break;
 273         }
 274 }
 275
 276 /*
 277  * i2c_probe: Use write access. Allows to identify addresses that are
 278  *            write-only (like the config register of dual-port EEPROMs)
 279  */
 280 static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
 281 {
 282         struct i2c *i2c_base = omap24_get_base(adap);
 283         u16 status;
 284         int res = 1; /* default = fail */
 285
 286         if (chip == readw(&i2c_base->oa))
 287                 return res;
 288
 289         /* Wait until bus is free */
 290         if (wait_for_bb(adap))
 291                 return res;
 292
 293         /* No data transfer, slave addr only */
 294         writew(chip, &i2c_base->sa);
 295         /* Stop bit needed here */
 296         writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
 297                I2C_CON_STP, &i2c_base->con);
 298
 299         status = wait_for_event(adap);
 300
 301         if ((status & ~I2C_STAT_XRDY) == 0 || (status & I2C_STAT_AL)) {
 302                 /*
 303                  * With current high-level command implementation, notifying
 304                  * the user shall flood the console with 127 messages. If
 305                  * silent exit is desired upon unconfigured bus, remove the
 306                  * following 'if' section:
 307                  */
 308                 if (status == I2C_STAT_XRDY)
 309                         printf("i2c_probe: pads on bus %d probably not configured (status=0x%x)\n",
 310                                adap->hwadapnr, status);
 311
 312                 goto pr_exit;
 313         }
 314
 315         /* Check for ACK (!NAK) */
 316         if (!(status & I2C_STAT_NACK)) {
 317                 res = 0;                                /* Device found */
 318                 udelay(adap->waitdelay);/* Required by AM335X in SPL */
 319                 /* Abort transfer (force idle state) */
 320                 writew(I2C_CON_MST | I2C_CON_TRX, &i2c_base->con); /* Reset */
 321                 udelay(1000);
 322                 writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_TRX |
 323                        I2C_CON_STP, &i2c_base->con);            /* STP */
 324         }
 325 pr_exit:
 326         flush_fifo(adap);
 327         writew(0xFFFF, &i2c_base->stat);
 328         return res;
 329 }
 330
 331 /*
 332  * i2c_read: Function now uses a single I2C read transaction with bulk transfer
 333  *           of the requested number of bytes (note that the 'i2c md' command
 334  *           limits this to 16 bytes anyway). If CONFIG_I2C_REPEATED_START is
 335  *           defined in the board config header, this transaction shall be with
 336  *           Repeated Start (Sr) between the address and data phases; otherwise
 337  *           Stop-Start (P-S) shall be used (some I2C chips do require a P-S).
 338  *           The address (reg offset) may be 0, 1 or 2 bytes long.
 339  *           Function now reads correctly from chips that return more than one
 340  *           byte of data per addressed register (like TI temperature sensors),
 341  *           or that do not need a register address at all (such as some clock
 342  *           distributors).
 343  */
 344 static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
 345                            int alen, uchar *buffer, int len)
 346 {
 347         struct i2c *i2c_base = omap24_get_base(adap);
 348         int i2c_error = 0;
 349         u16 status;
 350
 351         if (alen < 0) {
 352                 puts("I2C read: addr len < 0\n");
 353                 return 1;
 354         }
 355         if (len < 0) {
 356                 puts("I2C read: data len < 0\n");
 357                 return 1;
 358         }
 359         if (buffer == NULL) {
 360                 puts("I2C read: NULL pointer passed\n");
 361                 return 1;
 362         }
 363
 364         if (alen > 2) {
 365                 printf("I2C read: addr len %d not supported\n", alen);
 366                 return 1;
 367         }
 368
 369         if (addr + len > (1 << 16)) {
 370                 puts("I2C read: address out of range\n");
 371                 return 1;
 372         }
 373
 374         /* Wait until bus not busy */
 375         if (wait_for_bb(adap))
 376                 return 1;
 377
 378         /* Zero, one or two bytes reg address (offset) */
 379         writew(alen, &i2c_base->cnt);
 380         /* Set slave address */
 381         writew(chip, &i2c_base->sa);
 382
 383         if (alen) {
 384                 /* Must write reg offset first */
 385 #ifdef CONFIG_I2C_REPEATED_START
 386                 /* No stop bit, use Repeated Start (Sr) */
 387                 writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
 388                        I2C_CON_TRX, &i2c_base->con);
 389 #else
 390                 /* Stop - Start (P-S) */
 391                 writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP |
 392                        I2C_CON_TRX, &i2c_base->con);
 393 #endif
 394                 /* Send register offset */
 395                 while (1) {
 396                         status = wait_for_event(adap);
 397                         /* Try to identify bus that is not padconf'd for I2C */
 398                         if (status == I2C_STAT_XRDY) {
 399                                 i2c_error = 2;
 400                                 printf("i2c_read (addr phase): pads on bus %d probably not configured (status=0x%x)\n",
 401                                        adap->hwadapnr, status);
 402                                 goto rd_exit;
 403                         }
 404                         if (status == 0 || (status & I2C_STAT_NACK)) {
 405                                 i2c_error = 1;
 406                                 printf("i2c_read: error waiting for addr ACK (status=0x%x)\n",
 407                                        status);
 408                                 goto rd_exit;
 409                         }
 410                         if (alen) {
 411                                 if (status & I2C_STAT_XRDY) {
 412                                         alen--;
 413                                         /* Do we have to use byte access? */
 414                                         writeb((addr >> (8 * alen)) & 0xff,
 415                                                &i2c_base->data);
 416                                         writew(I2C_STAT_XRDY, &i2c_base->stat);
 417                                 }
 418                         }
 419                         if (status & I2C_STAT_ARDY) {
 420                                 writew(I2C_STAT_ARDY, &i2c_base->stat);
 421                                 break;
 422                         }
 423                 }
 424         }
 425         /* Set slave address */
 426         writew(chip, &i2c_base->sa);
 427         /* Read len bytes from slave */
 428         writew(len, &i2c_base->cnt);
 429         /* Need stop bit here */
 430         writew(I2C_CON_EN | I2C_CON_MST |
 431                I2C_CON_STT | I2C_CON_STP,
 432                &i2c_base->con);
 433
 434         /* Receive data */
 435         while (1) {
 436                 status = wait_for_event(adap);
 437                 /*
 438                  * Try to identify bus that is not padconf'd for I2C. This
 439                  * state could be left over from previous transactions if
 440                  * the address phase is skipped due to alen=0.
 441                  */
 442                 if (status == I2C_STAT_XRDY) {
 443                         i2c_error = 2;
 444                         printf("i2c_read (data phase): pads on bus %d probably not configured (status=0x%x)\n",
 445                                adap->hwadapnr, status);
 446                         goto rd_exit;
 447                 }
 448                 if (status == 0 || (status & I2C_STAT_NACK)) {
 449                         i2c_error = 1;
 450                         goto rd_exit;
 451                 }
 452                 if (status & I2C_STAT_RRDY) {
 453                         *buffer++ = readb(&i2c_base->data);
 454                         writew(I2C_STAT_RRDY, &i2c_base->stat);
 455                 }
 456                 if (status & I2C_STAT_ARDY) {
 457                         writew(I2C_STAT_ARDY, &i2c_base->stat);
 458                         break;
 459                 }
 460         }
 461
 462 rd_exit:
 463         flush_fifo(adap);
 464         writew(0xFFFF, &i2c_base->stat);
 465         return i2c_error;
 466 }
 467
 468 /* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */
 469 static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
 470                             int alen, uchar *buffer, int len)
 471 {
 472         struct i2c *i2c_base = omap24_get_base(adap);
 473         int i;
 474         u16 status;
 475         int i2c_error = 0;
 476         int timeout = I2C_TIMEOUT;
 477
 478         if (alen < 0) {
 479                 puts("I2C write: addr len < 0\n");
 480                 return 1;
 481         }
 482
 483         if (len < 0) {
 484                 puts("I2C write: data len < 0\n");
 485                 return 1;
 486         }
 487
 488         if (buffer == NULL) {
 489                 puts("I2C write: NULL pointer passed\n");
 490                 return 1;
 491         }
 492
 493         if (alen > 2) {
 494                 printf("I2C write: addr len %d not supported\n", alen);
 495                 return 1;
 496         }
 497
 498         if (addr + len > (1 << 16)) {
 499                 printf("I2C write: address 0x%x + 0x%x out of range\n",
 500                        addr, len);
 501                 return 1;
 502         }
 503
 504         /* Wait until bus not busy */
 505         if (wait_for_bb(adap))
 506                 return 1;
 507
 508         /* Start address phase - will write regoffset + len bytes data */
 509         writew(alen + len, &i2c_base->cnt);
 510         /* Set slave address */
 511         writew(chip, &i2c_base->sa);
 512         /* Stop bit needed here */
 513         writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
 514                I2C_CON_STP, &i2c_base->con);
 515
 516         while (alen) {
 517                 /* Must write reg offset (one or two bytes) */
 518                 status = wait_for_event(adap);
 519                 /* Try to identify bus that is not padconf'd for I2C */
 520                 if (status == I2C_STAT_XRDY) {
 521                         i2c_error = 2;
 522                         printf("i2c_write: pads on bus %d probably not configured (status=0x%x)\n",
 523                                adap->hwadapnr, status);
 524                         goto wr_exit;
 525                 }
 526                 if (status == 0 || (status & I2C_STAT_NACK)) {
 527                         i2c_error = 1;
 528                         printf("i2c_write: error waiting for addr ACK (status=0x%x)\n",
 529                                status);
 530                         goto wr_exit;
 531                 }
 532                 if (status & I2C_STAT_XRDY) {
 533                         alen--;
 534                         writeb((addr >> (8 * alen)) & 0xff, &i2c_base->data);
 535                         writew(I2C_STAT_XRDY, &i2c_base->stat);
 536                 } else {
 537                         i2c_error = 1;
 538                         printf("i2c_write: bus not ready for addr Tx (status=0x%x)\n",
 539                                status);
 540                         goto wr_exit;
 541                 }
 542         }
 543         /* Address phase is over, now write data */
 544         for (i = 0; i < len; i++) {
 545                 status = wait_for_event(adap);
 546                 if (status == 0 || (status & I2C_STAT_NACK)) {
 547                         i2c_error = 1;
 548                         printf("i2c_write: error waiting for data ACK (status=0x%x)\n",
 549                                status);
 550                         goto wr_exit;
 551                 }
 552                 if (status & I2C_STAT_XRDY) {
 553                         writeb(buffer[i], &i2c_base->data);
 554                         writew(I2C_STAT_XRDY, &i2c_base->stat);
 555                 } else {
 556                         i2c_error = 1;
 557                         printf("i2c_write: bus not ready for data Tx (i=%d)\n",
 558                                i);
 559                         goto wr_exit;
 560                 }
 561         }
 562         /*
 563          * poll ARDY bit for making sure that last byte really has been
 564          * transferred on the bus.
 565          */
 566         do {
 567                 status = wait_for_event(adap);
 568         } while (!(status & I2C_STAT_ARDY) && timeout--);
 569         if (timeout <= 0)
 570                 printf("i2c_write: timed out writig last byte!\n");
 571
 572 wr_exit:
 573         flush_fifo(adap);
 574         writew(0xFFFF, &i2c_base->stat);
 575         return i2c_error;
 576 }
 577
 578 /*
 579  * Wait for the bus to be free by checking the Bus Busy (BB)
 580  * bit to become clear
 581  */
 582 static int wait_for_bb(struct i2c_adapter *adap)
 583 {
 584         struct i2c *i2c_base = omap24_get_base(adap);
 585         int timeout = I2C_TIMEOUT;
 586         u16 stat;
 587
 588         writew(0xFFFF, &i2c_base->stat);        /* clear current interrupts...*/
 589 #if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
 590         while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
 591 #else
 592         /* Read RAW status */
 593         while ((stat = readw(&i2c_base->irqstatus_raw) &
 594                 I2C_STAT_BB) && timeout--) {
 595 #endif
 596                 writew(stat, &i2c_base->stat);
 597                 udelay(adap->waitdelay);
 598         }
 599
 600         if (timeout <= 0) {
 601                 printf("Timed out in wait_for_bb: status=%04x\n",
 602                        stat);
 603                 return 1;
 604         }
 605         writew(0xFFFF, &i2c_base->stat);         /* clear delayed stuff*/
 606         return 0;
 607 }
 608
 609 /*
 610  * Wait for the I2C controller to complete current action
 611  * and update status
 612  */
 613 static u16 wait_for_event(struct i2c_adapter *adap)
 614 {
 615         struct i2c *i2c_base = omap24_get_base(adap);
 616         u16 status;
 617         int timeout = I2C_TIMEOUT;
 618
 619         do {
 620                 udelay(adap->waitdelay);
 621 #if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
 622                 status = readw(&i2c_base->stat);
 623 #else
 624                 /* Read RAW status */
 625                 status = readw(&i2c_base->irqstatus_raw);
 626 #endif
 627         } while (!(status &
 628                    (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
 629                     I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
 630                     I2C_STAT_AL)) && timeout--);
 631
 632         if (timeout <= 0) {
 633                 printf("Timed out in wait_for_event: status=%04x\n",
 634                        status);
 635                 /*
 636                  * If status is still 0 here, probably the bus pads have
 637                  * not been configured for I2C, and/or pull-ups are missing.
 638                  */
 639                 printf("Check if pads/pull-ups of bus %d are properly configured\n",
 640                        adap->hwadapnr);
 641                 writew(0xFFFF, &i2c_base->stat);
 642                 status = 0;
 643         }
 644
 645         return status;
 646 }
 647
 648 static struct i2c *omap24_get_base(struct i2c_adapter *adap)
 649 {
 650         switch (adap->hwadapnr) {
 651         case 0:
 652                 return (struct i2c *)I2C_BASE1;
 653                 break;
 654         case 1:
 655                 return (struct i2c *)I2C_BASE2;
 656                 break;
 657 #if (I2C_BUS_MAX > 2)
 658         case 2:
 659                 return (struct i2c *)I2C_BASE3;
 660                 break;
 661 #if (I2C_BUS_MAX > 3)
 662         case 3:
 663                 return (struct i2c *)I2C_BASE4;
 664                 break;
 665 #if (I2C_BUS_MAX > 4)
 666         case 4:
 667                 return (struct i2c *)I2C_BASE5;
 668                 break;
 669 #endif
 670 #endif
 671 #endif
 672         default:
 673                 printf("wrong hwadapnr: %d\n", adap->hwadapnr);
 674                 break;
 675         }
 676         return NULL;
 677 }
 678
 679 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED1)
 680 #define CONFIG_SYS_OMAP24_I2C_SPEED1 CONFIG_SYS_OMAP24_I2C_SPEED
 681 #endif
 682 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE1)
 683 #define CONFIG_SYS_OMAP24_I2C_SLAVE1 CONFIG_SYS_OMAP24_I2C_SLAVE
 684 #endif
 685
 686 U_BOOT_I2C_ADAP_COMPLETE(omap24_0, omap24_i2c_init, omap24_i2c_probe,
 687                          omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
 688                          CONFIG_SYS_OMAP24_I2C_SPEED,
 689                          CONFIG_SYS_OMAP24_I2C_SLAVE,
 690                          0)
 691 U_BOOT_I2C_ADAP_COMPLETE(omap24_1, omap24_i2c_init, omap24_i2c_probe,
 692                          omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
 693                          CONFIG_SYS_OMAP24_I2C_SPEED1,
 694                          CONFIG_SYS_OMAP24_I2C_SLAVE1,
 695                          1)
 696 #if (I2C_BUS_MAX > 2)
 697 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED2)
 698 #define CONFIG_SYS_OMAP24_I2C_SPEED2 CONFIG_SYS_OMAP24_I2C_SPEED
 699 #endif
 700 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE2)
 701 #define CONFIG_SYS_OMAP24_I2C_SLAVE2 CONFIG_SYS_OMAP24_I2C_SLAVE
 702 #endif
 703
 704 U_BOOT_I2C_ADAP_COMPLETE(omap24_2, omap24_i2c_init, omap24_i2c_probe,
 705                          omap24_i2c_read, omap24_i2c_write, NULL,
 706                          CONFIG_SYS_OMAP24_I2C_SPEED2,
 707                          CONFIG_SYS_OMAP24_I2C_SLAVE2,
 708                          2)
 709 #if (I2C_BUS_MAX > 3)
 710 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED3)
 711 #define CONFIG_SYS_OMAP24_I2C_SPEED3 CONFIG_SYS_OMAP24_I2C_SPEED
 712 #endif
 713 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE3)
 714 #define CONFIG_SYS_OMAP24_I2C_SLAVE3 CONFIG_SYS_OMAP24_I2C_SLAVE
 715 #endif
 716
 717 U_BOOT_I2C_ADAP_COMPLETE(omap24_3, omap24_i2c_init, omap24_i2c_probe,
 718                          omap24_i2c_read, omap24_i2c_write, NULL,
 719                          CONFIG_SYS_OMAP24_I2C_SPEED3,
 720                          CONFIG_SYS_OMAP24_I2C_SLAVE3,
 721                          3)
 722 #if (I2C_BUS_MAX > 4)
 723 #if !defined(CONFIG_SYS_OMAP24_I2C_SPEED4)
 724 #define CONFIG_SYS_OMAP24_I2C_SPEED4 CONFIG_SYS_OMAP24_I2C_SPEED
 725 #endif
 726 #if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE4)
 727 #define CONFIG_SYS_OMAP24_I2C_SLAVE4 CONFIG_SYS_OMAP24_I2C_SLAVE
 728 #endif
 729
 730 U_BOOT_I2C_ADAP_COMPLETE(omap24_4, omap24_i2c_init, omap24_i2c_probe,
 731                          omap24_i2c_read, omap24_i2c_write, NULL,
 732                          CONFIG_SYS_OMAP24_I2C_SPEED4,
 733                          CONFIG_SYS_OMAP24_I2C_SLAVE4,
 734                          4)
 735 #endif
 736 #endif
 737 #endif