drivers/mtd/nand/nand_base.c

   1 /*
   2  *  drivers/mtd/nand.c
   3  *
   4  *  Overview:
   5  *   This is the generic MTD driver for NAND flash devices. It should be
   6  *   capable of working with almost all NAND chips currently available.
   7  *   Basic support for AG-AND chips is provided.
   8  *
   9  *      Additional technical information is available on
  10  *      http://www.linux-mtd.infradead.org/doc/nand.html
  11  *
  12  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
  13  *                2002-2006 Thomas Gleixner (tglx@linutronix.de)
  14  *
  15  *  Credits:
  16  *      David Woodhouse for adding multichip support
  17  *
  18  *      Aleph One Ltd. and Toby Churchill Ltd. for supporting the
  19  *      rework for 2K page size chips
  20  *
  21  *  TODO:
  22  *      Enable cached programming for 2k page size chips
  23  *      Check, if mtd->ecctype should be set to MTD_ECC_HW
  24  *      if we have HW ecc support.
  25  *      The AG-AND chips have nice features for speed improvement,
  26  *      which are not supported yet. Read / program 4 pages in one go.
  27  *      BBT table is not serialized, has to be fixed
  28  *
  29  * This program is free software; you can redistribute it and/or modify
  30  * it under the terms of the GNU General Public License version 2 as
  31  * published by the Free Software Foundation.
  32  *
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/delay.h>
  37 #include <linux/errno.h>
  38 #include <linux/err.h>
  39 #include <linux/sched.h>
  40 #include <linux/slab.h>
  41 #include <linux/types.h>
  42 #include <linux/mtd/mtd.h>
  43 #include <linux/mtd/nand.h>
  44 #include <linux/mtd/nand_ecc.h>
  45 #include <linux/mtd/compatmac.h>
  46 #include <linux/interrupt.h>
  47 #include <linux/bitops.h>
  48 #include <linux/leds.h>
  49 #include <asm/io.h>
  50
  51 #ifdef CONFIG_MTD_PARTITIONS
  52 #include <linux/mtd/partitions.h>
  53 #endif
  54
  55 /* Define default oob placement schemes for large and small page devices */
  56 static struct nand_ecclayout nand_oob_8 = {
  57         .eccbytes = 3,
  58         .eccpos = {0, 1, 2},
  59         .oobfree = {
  60                 {.offset = 3,
  61                  .length = 2},
  62                 {.offset = 6,
  63                  .length = 2}}
  64 };
  65
  66 static struct nand_ecclayout nand_oob_16 = {
  67         .eccbytes = 6,
  68         .eccpos = {0, 1, 2, 3, 6, 7},
  69         .oobfree = {
  70                 {.offset = 8,
  71                  . length = 8}}
  72 };
  73
  74 static struct nand_ecclayout nand_oob_64 = {
  75         .eccbytes = 24,
  76         .eccpos = {
  77                    40, 41, 42, 43, 44, 45, 46, 47,
  78                    48, 49, 50, 51, 52, 53, 54, 55,
  79                    56, 57, 58, 59, 60, 61, 62, 63},
  80         .oobfree = {
  81                 {.offset = 2,
  82                  .length = 38}}
  83 };
  84
  85 static int nand_get_device(struct nand_chip *chip, struct mtd_info *mtd,
  86                            int new_state);
  87
  88 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
  89                              struct mtd_oob_ops *ops);
  90
  91 /*
  92  * For devices which display every fart in the system on a separate LED. Is
  93  * compiled away when LED support is disabled.
  94  */
  95 DEFINE_LED_TRIGGER(nand_led_trigger);
  96
  97 /**
  98  * nand_release_device - [GENERIC] release chip
  99  * @mtd:        MTD device structure
 100  *
 101  * Deselect, release chip lock and wake up anyone waiting on the device
 102  */
 103 static void nand_release_device(struct mtd_info *mtd)
 104 {
 105         struct nand_chip *chip = mtd->priv;
 106
 107         /* De-select the NAND device */
 108         chip->select_chip(mtd, -1);
 109
 110         /* Release the controller and the chip */
 111         spin_lock(&chip->controller->lock);
 112         chip->controller->active = NULL;
 113         chip->state = FL_READY;
 114         wake_up(&chip->controller->wq);
 115         spin_unlock(&chip->controller->lock);
 116 }
 117
 118 /**
 119  * nand_read_byte - [DEFAULT] read one byte from the chip
 120  * @mtd:        MTD device structure
 121  *
 122  * Default read function for 8bit buswith
 123  */
 124 static uint8_t nand_read_byte(struct mtd_info *mtd)
 125 {
 126         struct nand_chip *chip = mtd->priv;
 127         return readb(chip->IO_ADDR_R);
 128 }
 129
 130 /**
 131  * nand_read_byte16 - [DEFAULT] read one byte endianess aware from the chip
 132  * @mtd:        MTD device structure
 133  *
 134  * Default read function for 16bit buswith with
 135  * endianess conversion
 136  */
 137 static uint8_t nand_read_byte16(struct mtd_info *mtd)
 138 {
 139         struct nand_chip *chip = mtd->priv;
 140         return (uint8_t) cpu_to_le16(readw(chip->IO_ADDR_R));
 141 }
 142
 143 /**
 144  * nand_read_word - [DEFAULT] read one word from the chip
 145  * @mtd:        MTD device structure
 146  *
 147  * Default read function for 16bit buswith without
 148  * endianess conversion
 149  */
 150 static u16 nand_read_word(struct mtd_info *mtd)
 151 {
 152         struct nand_chip *chip = mtd->priv;
 153         return readw(chip->IO_ADDR_R);
 154 }
 155
 156 /**
 157  * nand_select_chip - [DEFAULT] control CE line
 158  * @mtd:        MTD device structure
 159  * @chipnr:     chipnumber to select, -1 for deselect
 160  *
 161  * Default select function for 1 chip devices.
 162  */
 163 static void nand_select_chip(struct mtd_info *mtd, int chipnr)
 164 {
 165         struct nand_chip *chip = mtd->priv;
 166
 167         switch (chipnr) {
 168         case -1:
 169                 chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
 170                 break;
 171         case 0:
 172                 break;
 173
 174         default:
 175                 BUG();
 176         }
 177 }
 178
 179 /**
 180  * nand_write_buf - [DEFAULT] write buffer to chip
 181  * @mtd:        MTD device structure
 182  * @buf:        data buffer
 183  * @len:        number of bytes to write
 184  *
 185  * Default write function for 8bit buswith
 186  */
 187 static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 188 {
 189         int i;
 190         struct nand_chip *chip = mtd->priv;
 191
 192         for (i = 0; i < len; i++)
 193                 writeb(buf[i], chip->IO_ADDR_W);
 194 }
 195
 196 /**
 197  * nand_read_buf - [DEFAULT] read chip data into buffer
 198  * @mtd:        MTD device structure
 199  * @buf:        buffer to store date
 200  * @len:        number of bytes to read
 201  *
 202  * Default read function for 8bit buswith
 203  */
 204 static void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 205 {
 206         int i;
 207         struct nand_chip *chip = mtd->priv;
 208
 209         for (i = 0; i < len; i++)
 210                 buf[i] = readb(chip->IO_ADDR_R);
 211 }
 212
 213 /**
 214  * nand_verify_buf - [DEFAULT] Verify chip data against buffer
 215  * @mtd:        MTD device structure
 216  * @buf:        buffer containing the data to compare
 217  * @len:        number of bytes to compare
 218  *
 219  * Default verify function for 8bit buswith
 220  */
 221 static int nand_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 222 {
 223         int i;
 224         struct nand_chip *chip = mtd->priv;
 225
 226         for (i = 0; i < len; i++)
 227                 if (buf[i] != readb(chip->IO_ADDR_R))
 228                         return -EFAULT;
 229         return 0;
 230 }
 231
 232 /**
 233  * nand_write_buf16 - [DEFAULT] write buffer to chip
 234  * @mtd:        MTD device structure
 235  * @buf:        data buffer
 236  * @len:        number of bytes to write
 237  *
 238  * Default write function for 16bit buswith
 239  */
 240 static void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
 241 {
 242         int i;
 243         struct nand_chip *chip = mtd->priv;
 244         u16 *p = (u16 *) buf;
 245         len >>= 1;
 246
 247         for (i = 0; i < len; i++)
 248                 writew(p[i], chip->IO_ADDR_W);
 249
 250 }
 251
 252 /**
 253  * nand_read_buf16 - [DEFAULT] read chip data into buffer
 254  * @mtd:        MTD device structure
 255  * @buf:        buffer to store date
 256  * @len:        number of bytes to read
 257  *
 258  * Default read function for 16bit buswith
 259  */
 260 static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
 261 {
 262         int i;
 263         struct nand_chip *chip = mtd->priv;
 264         u16 *p = (u16 *) buf;
 265         len >>= 1;
 266
 267         for (i = 0; i < len; i++)
 268                 p[i] = readw(chip->IO_ADDR_R);
 269 }
 270
 271 /**
 272  * nand_verify_buf16 - [DEFAULT] Verify chip data against buffer
 273  * @mtd:        MTD device structure
 274  * @buf:        buffer containing the data to compare
 275  * @len:        number of bytes to compare
 276  *
 277  * Default verify function for 16bit buswith
 278  */
 279 static int nand_verify_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
 280 {
 281         int i;
 282         struct nand_chip *chip = mtd->priv;
 283         u16 *p = (u16 *) buf;
 284         len >>= 1;
 285
 286         for (i = 0; i < len; i++)
 287                 if (p[i] != readw(chip->IO_ADDR_R))
 288                         return -EFAULT;
 289
 290         return 0;
 291 }
 292
 293 /**
 294  * nand_block_bad - [DEFAULT] Read bad block marker from the chip
 295  * @mtd:        MTD device structure
 296  * @ofs:        offset from device start
 297  * @getchip:    0, if the chip is already selected
 298  *
 299  * Check, if the block is bad.
 300  */
 301 static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
 302 {
 303         int page, chipnr, res = 0;
 304         struct nand_chip *chip = mtd->priv;
 305         u16 bad;
 306
 307         page = (int)(ofs >> chip->page_shift) & chip->pagemask;
 308
 309         if (getchip) {
 310                 chipnr = (int)(ofs >> chip->chip_shift);
 311
 312                 nand_get_device(chip, mtd, FL_READING);
 313
 314                 /* Select the NAND device */
 315                 chip->select_chip(mtd, chipnr);
 316         }
 317
 318         if (chip->options & NAND_BUSWIDTH_16) {
 319                 chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos & 0xFE,
 320                               page);
 321                 bad = cpu_to_le16(chip->read_word(mtd));
 322                 if (chip->badblockpos & 0x1)
 323                         bad >>= 8;
 324                 if ((bad & 0xFF) != 0xff)
 325                         res = 1;
 326         } else {
 327                 chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos, page);
 328                 if (chip->read_byte(mtd) != 0xff)
 329                         res = 1;
 330         }
 331
 332         if (getchip)
 333                 nand_release_device(mtd);
 334
 335         return res;
 336 }
 337
 338 /**
 339  * nand_default_block_markbad - [DEFAULT] mark a block bad
 340  * @mtd:        MTD device structure
 341  * @ofs:        offset from device start
 342  *
 343  * This is the default implementation, which can be overridden by
 344  * a hardware specific driver.
 345 */
 346 static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 347 {
 348         struct nand_chip *chip = mtd->priv;
 349         uint8_t buf[2] = { 0, 0 };
 350         int block, ret;
 351
 352         /* Get block number */
 353         block = (int)(ofs >> chip->bbt_erase_shift);
 354         if (chip->bbt)
 355                 chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
 356
 357         /* Do we have a flash based bad block table ? */
 358         if (chip->options & NAND_USE_FLASH_BBT)
 359                 ret = nand_update_bbt(mtd, ofs);
 360         else {
 361                 /* We write two bytes, so we dont have to mess with 16 bit
 362                  * access
 363                  */
 364                 nand_get_device(chip, mtd, FL_WRITING);
 365                 ofs += mtd->oobsize;
 366                 chip->ops.len = chip->ops.ooblen = 2;
 367                 chip->ops.datbuf = NULL;
 368                 chip->ops.oobbuf = buf;
 369                 chip->ops.ooboffs = chip->badblockpos & ~0x01;
 370
 371                 ret = nand_do_write_oob(mtd, ofs, &chip->ops);
 372                 nand_release_device(mtd);
 373         }
 374         if (!ret)
 375                 mtd->ecc_stats.badblocks++;
 376
 377         return ret;
 378 }
 379
 380 /**
 381  * nand_check_wp - [GENERIC] check if the chip is write protected
 382  * @mtd:        MTD device structure
 383  * Check, if the device is write protected
 384  *
 385  * The function expects, that the device is already selected
 386  */
 387 static int nand_check_wp(struct mtd_info *mtd)
 388 {
 389         struct nand_chip *chip = mtd->priv;
 390         /* Check the WP bit */
 391         chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
 392         return (chip->read_byte(mtd) & NAND_STATUS_WP) ? 0 : 1;
 393 }
 394
 395 /**
 396  * nand_block_checkbad - [GENERIC] Check if a block is marked bad
 397  * @mtd:        MTD device structure
 398  * @ofs:        offset from device start
 399  * @getchip:    0, if the chip is already selected
 400  * @allowbbt:   1, if its allowed to access the bbt area
 401  *
 402  * Check, if the block is bad. Either by reading the bad block table or
 403  * calling of the scan function.
 404  */
 405 static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip,
 406                                int allowbbt)
 407 {
 408         struct nand_chip *chip = mtd->priv;
 409
 410         if (!chip->bbt)
 411                 return chip->block_bad(mtd, ofs, getchip);
 412
 413         /* Return info from the table */
 414         return nand_isbad_bbt(mtd, ofs, allowbbt);
 415 }
 416
 417 /*
 418  * Wait for the ready pin, after a command
 419  * The timeout is catched later.
 420  */
 421 void nand_wait_ready(struct mtd_info *mtd)
 422 {
 423         struct nand_chip *chip = mtd->priv;
 424         unsigned long timeo = jiffies + 2;
 425
 426         led_trigger_event(nand_led_trigger, LED_FULL);
 427         /* wait until command is processed or timeout occures */
 428         do {
 429                 if (chip->dev_ready(mtd))
 430                         break;
 431                 touch_softlockup_watchdog();
 432         } while (time_before(jiffies, timeo));
 433         led_trigger_event(nand_led_trigger, LED_OFF);
 434 }
 435 EXPORT_SYMBOL_GPL(nand_wait_ready);
 436
 437 /**
 438  * nand_command - [DEFAULT] Send command to NAND device
 439  * @mtd:        MTD device structure
 440  * @command:    the command to be sent
 441  * @column:     the column address for this command, -1 if none
 442  * @page_addr:  the page address for this command, -1 if none
 443  *
 444  * Send command to NAND device. This function is used for small page
 445  * devices (256/512 Bytes per page)
 446  */
 447 static void nand_command(struct mtd_info *mtd, unsigned int command,
 448                          int column, int page_addr)
 449 {
 450         register struct nand_chip *chip = mtd->priv;
 451         int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
 452
 453         /*
 454          * Write out the command to the device.
 455          */
 456         if (command == NAND_CMD_SEQIN) {
 457                 int readcmd;
 458
 459                 if (column >= mtd->writesize) {
 460                         /* OOB area */
 461                         column -= mtd->writesize;
 462                         readcmd = NAND_CMD_READOOB;
 463                 } else if (column < 256) {
 464                         /* First 256 bytes --> READ0 */
 465                         readcmd = NAND_CMD_READ0;
 466                 } else {
 467                         column -= 256;
 468                         readcmd = NAND_CMD_READ1;
 469                 }
 470                 chip->cmd_ctrl(mtd, readcmd, ctrl);
 471                 ctrl &= ~NAND_CTRL_CHANGE;
 472         }
 473         chip->cmd_ctrl(mtd, command, ctrl);
 474
 475         /*
 476          * Address cycle, when necessary
 477          */
 478         ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
 479         /* Serially input address */
 480         if (column != -1) {
 481                 /* Adjust columns for 16 bit buswidth */
 482                 if (chip->options & NAND_BUSWIDTH_16)
 483                         column >>= 1;
 484                 chip->cmd_ctrl(mtd, column, ctrl);
 485                 ctrl &= ~NAND_CTRL_CHANGE;
 486         }
 487         if (page_addr != -1) {
 488                 chip->cmd_ctrl(mtd, page_addr, ctrl);
 489                 ctrl &= ~NAND_CTRL_CHANGE;
 490                 chip->cmd_ctrl(mtd, page_addr >> 8, ctrl);
 491                 /* One more address cycle for devices > 32MiB */
 492                 if (chip->chipsize > (32 << 20))
 493                         chip->cmd_ctrl(mtd, page_addr >> 16, ctrl);
 494         }
 495         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 496
 497         /*
 498          * program and erase have their own busy handlers
 499          * status and sequential in needs no delay
 500          */
 501         switch (command) {
 502
 503         case NAND_CMD_PAGEPROG:
 504         case NAND_CMD_ERASE1:
 505         case NAND_CMD_ERASE2:
 506         case NAND_CMD_SEQIN:
 507         case NAND_CMD_STATUS:
 508                 return;
 509
 510         case NAND_CMD_RESET:
 511                 if (chip->dev_ready)
 512                         break;
 513                 udelay(chip->chip_delay);
 514                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
 515                                NAND_CTRL_CLE | NAND_CTRL_CHANGE);
 516                 chip->cmd_ctrl(mtd,
 517                                NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 518                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY)) ;
 519                 return;
 520
 521                 /* This applies to read commands */
 522         default:
 523                 /*
 524                  * If we don't have access to the busy pin, we apply the given
 525                  * command delay
 526                  */
 527                 if (!chip->dev_ready) {
 528                         udelay(chip->chip_delay);
 529                         return;
 530                 }
 531         }
 532         /* Apply this short delay always to ensure that we do wait tWB in
 533          * any case on any machine. */
 534         ndelay(100);
 535
 536         nand_wait_ready(mtd);
 537 }
 538
 539 /**
 540  * nand_command_lp - [DEFAULT] Send command to NAND large page device
 541  * @mtd:        MTD device structure
 542  * @command:    the command to be sent
 543  * @column:     the column address for this command, -1 if none
 544  * @page_addr:  the page address for this command, -1 if none
 545  *
 546  * Send command to NAND device. This is the version for the new large page
 547  * devices We dont have the separate regions as we have in the small page
 548  * devices.  We must emulate NAND_CMD_READOOB to keep the code compatible.
 549  */
 550 static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
 551                             int column, int page_addr)
 552 {
 553         register struct nand_chip *chip = mtd->priv;
 554
 555         /* Emulate NAND_CMD_READOOB */
 556         if (command == NAND_CMD_READOOB) {
 557                 column += mtd->writesize;
 558                 command = NAND_CMD_READ0;
 559         }
 560
 561         /* Command latch cycle */
 562         chip->cmd_ctrl(mtd, command & 0xff,
 563                        NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 564
 565         if (column != -1 || page_addr != -1) {
 566                 int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
 567
 568                 /* Serially input address */
 569                 if (column != -1) {
 570                         /* Adjust columns for 16 bit buswidth */
 571                         if (chip->options & NAND_BUSWIDTH_16)
 572                                 column >>= 1;
 573                         chip->cmd_ctrl(mtd, column, ctrl);
 574                         ctrl &= ~NAND_CTRL_CHANGE;
 575                         chip->cmd_ctrl(mtd, column >> 8, ctrl);
 576                 }
 577                 if (page_addr != -1) {
 578                         chip->cmd_ctrl(mtd, page_addr, ctrl);
 579                         chip->cmd_ctrl(mtd, page_addr >> 8,
 580                                        NAND_NCE | NAND_ALE);
 581                         /* One more address cycle for devices > 128MiB */
 582                         if (chip->chipsize > (128 << 20))
 583                                 chip->cmd_ctrl(mtd, page_addr >> 16,
 584                                                NAND_NCE | NAND_ALE);
 585                 }
 586         }
 587         chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
 588
 589         /*
 590          * program and erase have their own busy handlers
 591          * status, sequential in, and deplete1 need no delay
 592          */
 593         switch (command) {
 594
 595         case NAND_CMD_CACHEDPROG:
 596         case NAND_CMD_PAGEPROG:
 597         case NAND_CMD_ERASE1:
 598         case NAND_CMD_ERASE2:
 599         case NAND_CMD_SEQIN:
 600         case NAND_CMD_RNDIN:
 601         case NAND_CMD_STATUS:
 602         case NAND_CMD_DEPLETE1:
 603                 return;
 604
 605                 /*
 606                  * read error status commands require only a short delay
 607                  */
 608         case NAND_CMD_STATUS_ERROR:
 609         case NAND_CMD_STATUS_ERROR0:
 610         case NAND_CMD_STATUS_ERROR1:
 611         case NAND_CMD_STATUS_ERROR2:
 612         case NAND_CMD_STATUS_ERROR3:
 613                 udelay(chip->chip_delay);
 614                 return;
 615
 616         case NAND_CMD_RESET:
 617                 if (chip->dev_ready)
 618                         break;
 619                 udelay(chip->chip_delay);
 620                 chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
 621                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 622                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 623                                NAND_NCE | NAND_CTRL_CHANGE);
 624                 while (!(chip->read_byte(mtd) & NAND_STATUS_READY)) ;
 625                 return;
 626
 627         case NAND_CMD_RNDOUT:
 628                 /* No ready / busy check necessary */
 629                 chip->cmd_ctrl(mtd, NAND_CMD_RNDOUTSTART,
 630                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 631                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 632                                NAND_NCE | NAND_CTRL_CHANGE);
 633                 return;
 634
 635         case NAND_CMD_READ0:
 636                 chip->cmd_ctrl(mtd, NAND_CMD_READSTART,
 637                                NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
 638                 chip->cmd_ctrl(mtd, NAND_CMD_NONE,
 639                                NAND_NCE | NAND_CTRL_CHANGE);
 640
 641                 /* This applies to read commands */
 642         default:
 643                 /*
 644                  * If we don't have access to the busy pin, we apply the given
 645                  * command delay
 646                  */
 647                 if (!chip->dev_ready) {
 648                         udelay(chip->chip_delay);
 649                         return;
 650                 }
 651         }
 652
 653         /* Apply this short delay always to ensure that we do wait tWB in
 654          * any case on any machine. */
 655         ndelay(100);
 656
 657         nand_wait_ready(mtd);
 658 }
 659
 660 /**
 661  * nand_get_device - [GENERIC] Get chip for selected access
 662  * @chip:       the nand chip descriptor
 663  * @mtd:        MTD device structure
 664  * @new_state:  the state which is requested
 665  *
 666  * Get the device and lock it for exclusive access
 667  */
 668 static int
 669 nand_get_device(struct nand_chip *chip, struct mtd_info *mtd, int new_state)
 670 {
 671         spinlock_t *lock = &chip->controller->lock;
 672         wait_queue_head_t *wq = &chip->controller->wq;
 673         DECLARE_WAITQUEUE(wait, current);
 674  retry:
 675         spin_lock(lock);
 676
 677         /* Hardware controller shared among independend devices */
 678         /* Hardware controller shared among independend devices */
 679         if (!chip->controller->active)
 680                 chip->controller->active = chip;
 681
 682         if (chip->controller->active == chip && chip->state == FL_READY) {
 683                 chip->state = new_state;
 684                 spin_unlock(lock);
 685                 return 0;
 686         }
 687         if (new_state == FL_PM_SUSPENDED) {
 688                 spin_unlock(lock);
 689                 return (chip->state == FL_PM_SUSPENDED) ? 0 : -EAGAIN;
 690         }
 691         set_current_state(TASK_UNINTERRUPTIBLE);
 692         add_wait_queue(wq, &wait);
 693         spin_unlock(lock);
 694         schedule();
 695         remove_wait_queue(wq, &wait);
 696         goto retry;
 697 }
 698
 699 /**
 700  * nand_wait - [DEFAULT]  wait until the command is done
 701  * @mtd:        MTD device structure
 702  * @chip:       NAND chip structure
 703  *
 704  * Wait for command done. This applies to erase and program only
 705  * Erase can take up to 400ms and program up to 20ms according to
 706  * general NAND and SmartMedia specs
 707  */
 708 static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
 709 {
 710
 711         unsigned long timeo = jiffies;
 712         int status, state = chip->state;
 713
 714         if (state == FL_ERASING)
 715                 timeo += (HZ * 400) / 1000;
 716         else
 717                 timeo += (HZ * 20) / 1000;
 718
 719         led_trigger_event(nand_led_trigger, LED_FULL);
 720
 721         /* Apply this short delay always to ensure that we do wait tWB in
 722          * any case on any machine. */
 723         ndelay(100);
 724
 725         if ((state == FL_ERASING) && (chip->options & NAND_IS_AND))
 726                 chip->cmdfunc(mtd, NAND_CMD_STATUS_MULTI, -1, -1);
 727         else
 728                 chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
 729
 730         while (time_before(jiffies, timeo)) {
 731                 if (chip->dev_ready) {
 732                         if (chip->dev_ready(mtd))
 733                                 break;
 734                 } else {
 735                         if (chip->read_byte(mtd) & NAND_STATUS_READY)
 736                                 break;
 737                 }
 738                 cond_resched();
 739         }
 740         led_trigger_event(nand_led_trigger, LED_OFF);
 741
 742         status = (int)chip->read_byte(mtd);
 743         return status;
 744 }
 745
 746 /**
 747  * nand_read_page_raw - [Intern] read raw page data without ecc
 748  * @mtd:        mtd info structure
 749  * @chip:       nand chip info structure
 750  * @buf:        buffer to store read data
 751  */
 752 static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
 753                               uint8_t *buf)
 754 {
 755         chip->read_buf(mtd, buf, mtd->writesize);
 756         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
 757         return 0;
 758 }
 759
 760 /**
 761  * nand_read_page_swecc - [REPLACABLE] software ecc based page read function
 762  * @mtd:        mtd info structure
 763  * @chip:       nand chip info structure
 764  * @buf:        buffer to store read data
 765  */
 766 static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
 767                                 uint8_t *buf)
 768 {
 769         int i, eccsize = chip->ecc.size;
 770         int eccbytes = chip->ecc.bytes;
 771         int eccsteps = chip->ecc.steps;
 772         uint8_t *p = buf;
 773         uint8_t *ecc_calc = chip->buffers->ecccalc;
 774         uint8_t *ecc_code = chip->buffers->ecccode;
 775         uint32_t *eccpos = chip->ecc.layout->eccpos;
 776
 777         chip->ecc.read_page_raw(mtd, chip, buf);
 778
 779         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
 780                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
 781
 782         for (i = 0; i < chip->ecc.total; i++)
 783                 ecc_code[i] = chip->oob_poi[eccpos[i]];
 784
 785         eccsteps = chip->ecc.steps;
 786         p = buf;
 787
 788         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 789                 int stat;
 790
 791                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
 792                 if (stat < 0)
 793                         mtd->ecc_stats.failed++;
 794                 else
 795                         mtd->ecc_stats.corrected += stat;
 796         }
 797         return 0;
 798 }
 799
 800 /**
 801  * nand_read_subpage - [REPLACABLE] software ecc based sub-page read function
 802  * @mtd:        mtd info structure
 803  * @chip:       nand chip info structure
 804  * @data_offs:  offset of requested data within the page
 805  * @readlen:    data length
 806  * @bufpoi:     buffer to store read data
 807  */
 808 static int nand_read_subpage(struct mtd_info *mtd, struct nand_chip *chip, uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi)
 809 {
 810         int start_step, end_step, num_steps;
 811         uint32_t *eccpos = chip->ecc.layout->eccpos;
 812         uint8_t *p;
 813         int data_col_addr, i, gaps = 0;
 814         int datafrag_len, eccfrag_len, aligned_len, aligned_pos;
 815         int busw = (chip->options & NAND_BUSWIDTH_16) ? 2 : 1;
 816
 817         /* Column address wihin the page aligned to ECC size (256bytes). */
 818         start_step = data_offs / chip->ecc.size;
 819         end_step = (data_offs + readlen - 1) / chip->ecc.size;
 820         num_steps = end_step - start_step + 1;
 821
 822         /* Data size aligned to ECC ecc.size*/
 823         datafrag_len = num_steps * chip->ecc.size;
 824         eccfrag_len = num_steps * chip->ecc.bytes;
 825
 826         data_col_addr = start_step * chip->ecc.size;
 827         /* If we read not a page aligned data */
 828         if (data_col_addr != 0)
 829                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_col_addr, -1);
 830
 831         p = bufpoi + data_col_addr;
 832         chip->read_buf(mtd, p, datafrag_len);
 833
 834         /* Calculate  ECC */
 835         for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size)
 836                 chip->ecc.calculate(mtd, p, &chip->buffers->ecccalc[i]);
 837
 838         /* The performance is faster if to position offsets
 839            according to ecc.pos. Let make sure here that
 840            there are no gaps in ecc positions */
 841         for (i = 0; i < eccfrag_len - 1; i++) {
 842                 if (eccpos[i + start_step * chip->ecc.bytes] + 1 !=
 843                         eccpos[i + start_step * chip->ecc.bytes + 1]) {
 844                         gaps = 1;
 845                         break;
 846                 }
 847         }
 848         if (gaps) {
 849                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
 850                 chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
 851         } else {
 852                 /* send the command to read the particular ecc bytes */
 853                 /* take care about buswidth alignment in read_buf */
 854                 aligned_pos = eccpos[start_step * chip->ecc.bytes] & ~(busw - 1);
 855                 aligned_len = eccfrag_len;
 856                 if (eccpos[start_step * chip->ecc.bytes] & (busw - 1))
 857                         aligned_len++;
 858                 if (eccpos[(start_step + num_steps) * chip->ecc.bytes] & (busw - 1))
 859                         aligned_len++;
 860
 861                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize + aligned_pos, -1);
 862                 chip->read_buf(mtd, &chip->oob_poi[aligned_pos], aligned_len);
 863         }
 864
 865         for (i = 0; i < eccfrag_len; i++)
 866                 chip->buffers->ecccode[i] = chip->oob_poi[eccpos[i + start_step * chip->ecc.bytes]];
 867
 868         p = bufpoi + data_col_addr;
 869         for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size) {
 870                 int stat;
 871
 872                 stat = chip->ecc.correct(mtd, p, &chip->buffers->ecccode[i], &chip->buffers->ecccalc[i]);
 873                 if (stat == -1)
 874                         mtd->ecc_stats.failed++;
 875                 else
 876                         mtd->ecc_stats.corrected += stat;
 877         }
 878         return 0;
 879 }
 880
 881 /**
 882  * nand_read_page_hwecc - [REPLACABLE] hardware ecc based page read function
 883  * @mtd:        mtd info structure
 884  * @chip:       nand chip info structure
 885  * @buf:        buffer to store read data
 886  *
 887  * Not for syndrome calculating ecc controllers which need a special oob layout
 888  */
 889 static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
 890                                 uint8_t *buf)
 891 {
 892         int i, eccsize = chip->ecc.size;
 893         int eccbytes = chip->ecc.bytes;
 894         int eccsteps = chip->ecc.steps;
 895         uint8_t *p = buf;
 896         uint8_t *ecc_calc = chip->buffers->ecccalc;
 897         uint8_t *ecc_code = chip->buffers->ecccode;
 898         uint32_t *eccpos = chip->ecc.layout->eccpos;
 899
 900         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 901                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
 902                 chip->read_buf(mtd, p, eccsize);
 903                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
 904         }
 905         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
 906
 907         for (i = 0; i < chip->ecc.total; i++)
 908                 ecc_code[i] = chip->oob_poi[eccpos[i]];
 909
 910         eccsteps = chip->ecc.steps;
 911         p = buf;
 912
 913         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 914                 int stat;
 915
 916                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
 917                 if (stat < 0)
 918                         mtd->ecc_stats.failed++;
 919                 else
 920                         mtd->ecc_stats.corrected += stat;
 921         }
 922         return 0;
 923 }
 924
 925 /**
 926  * nand_read_page_syndrome - [REPLACABLE] hardware ecc syndrom based page read
 927  * @mtd:        mtd info structure
 928  * @chip:       nand chip info structure
 929  * @buf:        buffer to store read data
 930  *
 931  * The hw generator calculates the error syndrome automatically. Therefor
 932  * we need a special oob layout and handling.
 933  */
 934 static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
 935                                    uint8_t *buf)
 936 {
 937         int i, eccsize = chip->ecc.size;
 938         int eccbytes = chip->ecc.bytes;
 939         int eccsteps = chip->ecc.steps;
 940         uint8_t *p = buf;
 941         uint8_t *oob = chip->oob_poi;
 942
 943         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 944                 int stat;
 945
 946                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
 947                 chip->read_buf(mtd, p, eccsize);
 948
 949                 if (chip->ecc.prepad) {
 950                         chip->read_buf(mtd, oob, chip->ecc.prepad);
 951                         oob += chip->ecc.prepad;
 952                 }
 953
 954                 chip->ecc.hwctl(mtd, NAND_ECC_READSYN);
 955                 chip->read_buf(mtd, oob, eccbytes);
 956                 stat = chip->ecc.correct(mtd, p, oob, NULL);
 957
 958                 if (stat < 0)
 959                         mtd->ecc_stats.failed++;
 960                 else
 961                         mtd->ecc_stats.corrected += stat;
 962
 963                 oob += eccbytes;
 964
 965                 if (chip->ecc.postpad) {
 966                         chip->read_buf(mtd, oob, chip->ecc.postpad);
 967                         oob += chip->ecc.postpad;
 968                 }
 969         }
 970
 971         /* Calculate remaining oob bytes */
 972         i = mtd->oobsize - (oob - chip->oob_poi);
 973         if (i)
 974                 chip->read_buf(mtd, oob, i);
 975
 976         return 0;
 977 }
 978
 979 /**
 980  * nand_transfer_oob - [Internal] Transfer oob to client buffer
 981  * @chip:       nand chip structure
 982  * @oob:        oob destination address
 983  * @ops:        oob ops structure
 984  * @len:        size of oob to transfer
 985  */
 986 static uint8_t *nand_transfer_oob(struct nand_chip *chip, uint8_t *oob,
 987                                   struct mtd_oob_ops *ops, size_t len)
 988 {
 989         switch(ops->mode) {
 990
 991         case MTD_OOB_PLACE:
 992         case MTD_OOB_RAW:
 993                 memcpy(oob, chip->oob_poi + ops->ooboffs, len);
 994                 return oob + len;
 995
 996         case MTD_OOB_AUTO: {
 997                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
 998                 uint32_t boffs = 0, roffs = ops->ooboffs;
 999                 size_t bytes = 0;
1000
1001                 for(; free->length && len; free++, len -= bytes) {
1002                         /* Read request not from offset 0 ? */
1003                         if (unlikely(roffs)) {
1004                                 if (roffs >= free->length) {
1005                                         roffs -= free->length;
1006                                         continue;
1007                                 }
1008                                 boffs = free->offset + roffs;
1009                                 bytes = min_t(size_t, len,
1010                                               (free->length - roffs));
1011                                 roffs = 0;
1012                         } else {
1013                                 bytes = min_t(size_t, len, free->length);
1014                                 boffs = free->offset;
1015                         }
1016                         memcpy(oob, chip->oob_poi + boffs, bytes);
1017                         oob += bytes;
1018                 }
1019                 return oob;
1020         }
1021         default:
1022                 BUG();
1023         }
1024         return NULL;
1025 }
1026
1027 /**
1028  * nand_do_read_ops - [Internal] Read data with ECC
1029  *
1030  * @mtd:        MTD device structure
1031  * @from:       offset to read from
1032  * @ops:        oob ops structure
1033  *
1034  * Internal function. Called with chip held.
1035  */
1036 static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
1037                             struct mtd_oob_ops *ops)
1038 {
1039         int chipnr, page, realpage, col, bytes, aligned;
1040         struct nand_chip *chip = mtd->priv;
1041         struct mtd_ecc_stats stats;
1042         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1043         int sndcmd = 1;
1044         int ret = 0;
1045         uint32_t readlen = ops->len;
1046         uint32_t oobreadlen = ops->ooblen;
1047         uint8_t *bufpoi, *oob, *buf;
1048
1049         stats = mtd->ecc_stats;
1050
1051         chipnr = (int)(from >> chip->chip_shift);
1052         chip->select_chip(mtd, chipnr);
1053
1054         realpage = (int)(from >> chip->page_shift);
1055         page = realpage & chip->pagemask;
1056
1057         col = (int)(from & (mtd->writesize - 1));
1058
1059         buf = ops->datbuf;
1060         oob = ops->oobbuf;
1061
1062         while(1) {
1063                 bytes = min(mtd->writesize - col, readlen);
1064                 aligned = (bytes == mtd->writesize);
1065
1066                 /* Is the current page in the buffer ? */
1067                 if (realpage != chip->pagebuf || oob) {
1068                         bufpoi = aligned ? buf : chip->buffers->databuf;
1069
1070                         if (likely(sndcmd)) {
1071                                 chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
1072                                 sndcmd = 0;
1073                         }
1074
1075                         /* Now read the page into the buffer */
1076                         if (unlikely(ops->mode == MTD_OOB_RAW))
1077                                 ret = chip->ecc.read_page_raw(mtd, chip, bufpoi);
1078                         else if (!aligned && NAND_SUBPAGE_READ(chip) && !oob)
1079                                 ret = chip->ecc.read_subpage(mtd, chip, col, bytes, bufpoi);
1080                         else
1081                                 ret = chip->ecc.read_page(mtd, chip, bufpoi);
1082                         if (ret < 0)
1083                                 break;
1084
1085                         /* Transfer not aligned data */
1086                         if (!aligned) {
1087                                 if (!NAND_SUBPAGE_READ(chip) && !oob)
1088                                         chip->pagebuf = realpage;
1089                                 memcpy(buf, chip->buffers->databuf + col, bytes);
1090                         }
1091
1092                         buf += bytes;
1093
1094                         if (unlikely(oob)) {
1095                                 /* Raw mode does data:oob:data:oob */
1096                                 if (ops->mode != MTD_OOB_RAW) {
1097                                         int toread = min(oobreadlen,
1098                                                 chip->ecc.layout->oobavail);
1099                                         if (toread) {
1100                                                 oob = nand_transfer_oob(chip,
1101                                                         oob, ops, toread);
1102                                                 oobreadlen -= toread;
1103                                         }
1104                                 } else
1105                                         buf = nand_transfer_oob(chip,
1106                                                 buf, ops, mtd->oobsize);
1107                         }
1108
1109                         if (!(chip->options & NAND_NO_READRDY)) {
1110                                 /*
1111                                  * Apply delay or wait for ready/busy pin. Do
1112                                  * this before the AUTOINCR check, so no
1113                                  * problems arise if a chip which does auto
1114                                  * increment is marked as NOAUTOINCR by the
1115                                  * board driver.
1116                                  */
1117                                 if (!chip->dev_ready)
1118                                         udelay(chip->chip_delay);
1119                                 else
1120                                         nand_wait_ready(mtd);
1121                         }
1122                 } else {
1123                         memcpy(buf, chip->buffers->databuf + col, bytes);
1124                         buf += bytes;
1125                 }
1126
1127                 readlen -= bytes;
1128
1129                 if (!readlen)
1130                         break;
1131
1132                 /* For subsequent reads align to page boundary. */
1133                 col = 0;
1134                 /* Increment page address */
1135                 realpage++;
1136
1137                 page = realpage & chip->pagemask;
1138                 /* Check, if we cross a chip boundary */
1139                 if (!page) {
1140                         chipnr++;
1141                         chip->select_chip(mtd, -1);
1142                         chip->select_chip(mtd, chipnr);
1143                 }
1144
1145                 /* Check, if the chip supports auto page increment
1146                  * or if we have hit a block boundary.
1147                  */
1148                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1149                         sndcmd = 1;
1150         }
1151
1152         ops->retlen = ops->len - (size_t) readlen;
1153         if (oob)
1154                 ops->oobretlen = ops->ooblen - oobreadlen;
1155
1156         if (ret)
1157                 return ret;
1158
1159         if (mtd->ecc_stats.failed - stats.failed)
1160                 return -EBADMSG;
1161
1162         return  mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
1163 }
1164
1165 /**
1166  * nand_read - [MTD Interface] MTD compability function for nand_do_read_ecc
1167  * @mtd:        MTD device structure
1168  * @from:       offset to read from
1169  * @len:        number of bytes to read
1170  * @retlen:     pointer to variable to store the number of read bytes
1171  * @buf:        the databuffer to put data
1172  *
1173  * Get hold of the chip and call nand_do_read
1174  */
1175 static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
1176                      size_t *retlen, uint8_t *buf)
1177 {
1178         struct nand_chip *chip = mtd->priv;
1179         int ret;
1180
1181         /* Do not allow reads past end of device */
1182         if ((from + len) > mtd->size)
1183                 return -EINVAL;
1184         if (!len)
1185                 return 0;
1186
1187         nand_get_device(chip, mtd, FL_READING);
1188
1189         chip->ops.len = len;
1190         chip->ops.datbuf = buf;
1191         chip->ops.oobbuf = NULL;
1192
1193         ret = nand_do_read_ops(mtd, from, &chip->ops);
1194
1195         *retlen = chip->ops.retlen;
1196
1197         nand_release_device(mtd);
1198
1199         return ret;
1200 }
1201
1202 /**
1203  * nand_read_oob_std - [REPLACABLE] the most common OOB data read function
1204  * @mtd:        mtd info structure
1205  * @chip:       nand chip info structure
1206  * @page:       page number to read
1207  * @sndcmd:     flag whether to issue read command or not
1208  */
1209 static int nand_read_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1210                              int page, int sndcmd)
1211 {
1212         if (sndcmd) {
1213                 chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1214                 sndcmd = 0;
1215         }
1216         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1217         return sndcmd;
1218 }
1219
1220 /**
1221  * nand_read_oob_syndrome - [REPLACABLE] OOB data read function for HW ECC
1222  *                          with syndromes
1223  * @mtd:        mtd info structure
1224  * @chip:       nand chip info structure
1225  * @page:       page number to read
1226  * @sndcmd:     flag whether to issue read command or not
1227  */
1228 static int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1229                                   int page, int sndcmd)
1230 {
1231         uint8_t *buf = chip->oob_poi;
1232         int length = mtd->oobsize;
1233         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1234         int eccsize = chip->ecc.size;
1235         uint8_t *bufpoi = buf;
1236         int i, toread, sndrnd = 0, pos;
1237
1238         chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
1239         for (i = 0; i < chip->ecc.steps; i++) {
1240                 if (sndrnd) {
1241                         pos = eccsize + i * (eccsize + chunk);
1242                         if (mtd->writesize > 512)
1243                                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, pos, -1);
1244                         else
1245                                 chip->cmdfunc(mtd, NAND_CMD_READ0, pos, page);
1246                 } else
1247                         sndrnd = 1;
1248                 toread = min_t(int, length, chunk);
1249                 chip->read_buf(mtd, bufpoi, toread);
1250                 bufpoi += toread;
1251                 length -= toread;
1252         }
1253         if (length > 0)
1254                 chip->read_buf(mtd, bufpoi, length);
1255
1256         return 1;
1257 }
1258
1259 /**
1260  * nand_write_oob_std - [REPLACABLE] the most common OOB data write function
1261  * @mtd:        mtd info structure
1262  * @chip:       nand chip info structure
1263  * @page:       page number to write
1264  */
1265 static int nand_write_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1266                               int page)
1267 {
1268         int status = 0;
1269         const uint8_t *buf = chip->oob_poi;
1270         int length = mtd->oobsize;
1271
1272         chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
1273         chip->write_buf(mtd, buf, length);
1274         /* Send command to program the OOB data */
1275         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1276
1277         status = chip->waitfunc(mtd, chip);
1278
1279         return status & NAND_STATUS_FAIL ? -EIO : 0;
1280 }
1281
1282 /**
1283  * nand_write_oob_syndrome - [REPLACABLE] OOB data write function for HW ECC
1284  *                           with syndrome - only for large page flash !
1285  * @mtd:        mtd info structure
1286  * @chip:       nand chip info structure
1287  * @page:       page number to write
1288  */
1289 static int nand_write_oob_syndrome(struct mtd_info *mtd,
1290                                    struct nand_chip *chip, int page)
1291 {
1292         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1293         int eccsize = chip->ecc.size, length = mtd->oobsize;
1294         int i, len, pos, status = 0, sndcmd = 0, steps = chip->ecc.steps;
1295         const uint8_t *bufpoi = chip->oob_poi;
1296
1297         /*
1298          * data-ecc-data-ecc ... ecc-oob
1299          * or
1300          * data-pad-ecc-pad-data-pad .... ecc-pad-oob
1301          */
1302         if (!chip->ecc.prepad && !chip->ecc.postpad) {
1303                 pos = steps * (eccsize + chunk);
1304                 steps = 0;
1305         } else
1306                 pos = eccsize;
1307
1308         chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
1309         for (i = 0; i < steps; i++) {
1310                 if (sndcmd) {
1311                         if (mtd->writesize <= 512) {
1312                                 uint32_t fill = 0xFFFFFFFF;
1313
1314                                 len = eccsize;
1315                                 while (len > 0) {
1316                                         int num = min_t(int, len, 4);
1317                                         chip->write_buf(mtd, (uint8_t *)&fill,
1318                                                         num);
1319                                         len -= num;
1320                                 }
1321                         } else {
1322                                 pos = eccsize + i * (eccsize + chunk);
1323                                 chip->cmdfunc(mtd, NAND_CMD_RNDIN, pos, -1);
1324                         }
1325                 } else
1326                         sndcmd = 1;
1327                 len = min_t(int, length, chunk);
1328                 chip->write_buf(mtd, bufpoi, len);
1329                 bufpoi += len;
1330                 length -= len;
1331         }
1332         if (length > 0)
1333                 chip->write_buf(mtd, bufpoi, length);
1334
1335         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1336         status = chip->waitfunc(mtd, chip);
1337
1338         return status & NAND_STATUS_FAIL ? -EIO : 0;
1339 }
1340
1341 /**
1342  * nand_do_read_oob - [Intern] NAND read out-of-band
1343  * @mtd:        MTD device structure
1344  * @from:       offset to read from
1345  * @ops:        oob operations description structure
1346  *
1347  * NAND read out-of-band data from the spare area
1348  */
1349 static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
1350                             struct mtd_oob_ops *ops)
1351 {
1352         int page, realpage, chipnr, sndcmd = 1;
1353         struct nand_chip *chip = mtd->priv;
1354         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1355         int readlen = ops->ooblen;
1356         int len;
1357         uint8_t *buf = ops->oobbuf;
1358
1359         DEBUG(MTD_DEBUG_LEVEL3, "nand_read_oob: from = 0x%08Lx, len = %i\n",
1360               (unsigned long long)from, readlen);
1361
1362         if (ops->mode == MTD_OOB_AUTO)
1363                 len = chip->ecc.layout->oobavail;
1364         else
1365                 len = mtd->oobsize;
1366
1367         if (unlikely(ops->ooboffs >= len)) {
1368                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1369                         "Attempt to start read outside oob\n");
1370                 return -EINVAL;
1371         }
1372
1373         /* Do not allow reads past end of device */
1374         if (unlikely(from >= mtd->size ||
1375                      ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
1376                                         (from >> chip->page_shift)) * len)) {
1377                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1378                         "Attempt read beyond end of device\n");
1379                 return -EINVAL;
1380         }
1381
1382         chipnr = (int)(from >> chip->chip_shift);
1383         chip->select_chip(mtd, chipnr);
1384
1385         /* Shift to get page */
1386         realpage = (int)(from >> chip->page_shift);
1387         page = realpage & chip->pagemask;
1388
1389         while(1) {
1390                 sndcmd = chip->ecc.read_oob(mtd, chip, page, sndcmd);
1391
1392                 len = min(len, readlen);
1393                 buf = nand_transfer_oob(chip, buf, ops, len);
1394
1395                 if (!(chip->options & NAND_NO_READRDY)) {
1396                         /*
1397                          * Apply delay or wait for ready/busy pin. Do this
1398                          * before the AUTOINCR check, so no problems arise if a
1399                          * chip which does auto increment is marked as
1400                          * NOAUTOINCR by the board driver.
1401                          */
1402                         if (!chip->dev_ready)
1403                                 udelay(chip->chip_delay);
1404                         else
1405                                 nand_wait_ready(mtd);
1406                 }
1407
1408                 readlen -= len;
1409                 if (!readlen)
1410                         break;
1411
1412                 /* Increment page address */
1413                 realpage++;
1414
1415                 page = realpage & chip->pagemask;
1416                 /* Check, if we cross a chip boundary */
1417                 if (!page) {
1418                         chipnr++;
1419                         chip->select_chip(mtd, -1);
1420                         chip->select_chip(mtd, chipnr);
1421                 }
1422
1423                 /* Check, if the chip supports auto page increment
1424                  * or if we have hit a block boundary.
1425                  */
1426                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1427                         sndcmd = 1;
1428         }
1429
1430         ops->oobretlen = ops->ooblen;
1431         return 0;
1432 }
1433
1434 /**
1435  * nand_read_oob - [MTD Interface] NAND read data and/or out-of-band
1436  * @mtd:        MTD device structure
1437  * @from:       offset to read from
1438  * @ops:        oob operation description structure
1439  *
1440  * NAND read data and/or out-of-band data
1441  */
1442 static int nand_read_oob(struct mtd_info *mtd, loff_t from,
1443                          struct mtd_oob_ops *ops)
1444 {
1445         struct nand_chip *chip = mtd->priv;
1446         int ret = -ENOTSUPP;
1447
1448         ops->retlen = 0;
1449
1450         /* Do not allow reads past end of device */
1451         if (ops->datbuf && (from + ops->len) > mtd->size) {
1452                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1453                       "Attempt read beyond end of device\n");
1454                 return -EINVAL;
1455         }
1456
1457         nand_get_device(chip, mtd, FL_READING);
1458
1459         switch(ops->mode) {
1460         case MTD_OOB_PLACE:
1461         case MTD_OOB_AUTO:
1462         case MTD_OOB_RAW:
1463                 break;
1464
1465         default:
1466                 goto out;
1467         }
1468
1469         if (!ops->datbuf)
1470                 ret = nand_do_read_oob(mtd, from, ops);
1471         else
1472                 ret = nand_do_read_ops(mtd, from, ops);
1473
1474  out:
1475         nand_release_device(mtd);
1476         return ret;
1477 }
1478
1479
1480 /**
1481  * nand_write_page_raw - [Intern] raw page write function
1482  * @mtd:        mtd info structure
1483  * @chip:       nand chip info structure
1484  * @buf:        data buffer
1485  */
1486 static void nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1487                                 const uint8_t *buf)
1488 {
1489         chip->write_buf(mtd, buf, mtd->writesize);
1490         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1491 }
1492
1493 /**
1494  * nand_write_page_swecc - [REPLACABLE] software ecc based page write function
1495  * @mtd:        mtd info structure
1496  * @chip:       nand chip info structure
1497  * @buf:        data buffer
1498  */
1499 static void nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1500                                   const uint8_t *buf)
1501 {
1502         int i, eccsize = chip->ecc.size;
1503         int eccbytes = chip->ecc.bytes;
1504         int eccsteps = chip->ecc.steps;
1505         uint8_t *ecc_calc = chip->buffers->ecccalc;
1506         const uint8_t *p = buf;
1507         uint32_t *eccpos = chip->ecc.layout->eccpos;
1508
1509         /* Software ecc calculation */
1510         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1511                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1512
1513         for (i = 0; i < chip->ecc.total; i++)
1514                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1515
1516         chip->ecc.write_page_raw(mtd, chip, buf);
1517 }
1518
1519 /**
1520  * nand_write_page_hwecc - [REPLACABLE] hardware ecc based page write function
1521  * @mtd:        mtd info structure
1522  * @chip:       nand chip info structure
1523  * @buf:        data buffer
1524  */
1525 static void nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1526                                   const uint8_t *buf)
1527 {
1528         int i, eccsize = chip->ecc.size;
1529         int eccbytes = chip->ecc.bytes;
1530         int eccsteps = chip->ecc.steps;
1531         uint8_t *ecc_calc = chip->buffers->ecccalc;
1532         const uint8_t *p = buf;
1533         uint32_t *eccpos = chip->ecc.layout->eccpos;
1534
1535         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1536                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1537                 chip->write_buf(mtd, p, eccsize);
1538                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1539         }
1540
1541         for (i = 0; i < chip->ecc.total; i++)
1542                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1543
1544         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1545 }
1546
1547 /**
1548  * nand_write_page_syndrome - [REPLACABLE] hardware ecc syndrom based page write
1549  * @mtd:        mtd info structure
1550  * @chip:       nand chip info structure
1551  * @buf:        data buffer
1552  *
1553  * The hw generator calculates the error syndrome automatically. Therefor
1554  * we need a special oob layout and handling.
1555  */
1556 static void nand_write_page_syndrome(struct mtd_info *mtd,
1557                                     struct nand_chip *chip, const uint8_t *buf)
1558 {
1559         int i, eccsize = chip->ecc.size;
1560         int eccbytes = chip->ecc.bytes;
1561         int eccsteps = chip->ecc.steps;
1562         const uint8_t *p = buf;
1563         uint8_t *oob = chip->oob_poi;
1564
1565         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1566
1567                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1568                 chip->write_buf(mtd, p, eccsize);
1569
1570                 if (chip->ecc.prepad) {
1571                         chip->write_buf(mtd, oob, chip->ecc.prepad);
1572                         oob += chip->ecc.prepad;
1573                 }
1574
1575                 chip->ecc.calculate(mtd, p, oob);
1576                 chip->write_buf(mtd, oob, eccbytes);
1577                 oob += eccbytes;
1578
1579                 if (chip->ecc.postpad) {
1580                         chip->write_buf(mtd, oob, chip->ecc.postpad);
1581                         oob += chip->ecc.postpad;
1582                 }
1583         }
1584
1585         /* Calculate remaining oob bytes */
1586         i = mtd->oobsize - (oob - chip->oob_poi);
1587         if (i)
1588                 chip->write_buf(mtd, oob, i);
1589 }
1590
1591 /**
1592  * nand_write_page - [REPLACEABLE] write one page
1593  * @mtd:        MTD device structure
1594  * @chip:       NAND chip descriptor
1595  * @buf:        the data to write
1596  * @page:       page number to write
1597  * @cached:     cached programming
1598  * @raw:        use _raw version of write_page
1599  */
1600 static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
1601                            const uint8_t *buf, int page, int cached, int raw)
1602 {
1603         int status;
1604
1605         chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
1606
1607         if (unlikely(raw))
1608                 chip->ecc.write_page_raw(mtd, chip, buf);
1609         else
1610                 chip->ecc.write_page(mtd, chip, buf);
1611
1612         /*
1613          * Cached progamming disabled for now, Not sure if its worth the
1614          * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s)
1615          */
1616         cached = 0;
1617
1618         if (!cached || !(chip->options & NAND_CACHEPRG)) {
1619
1620                 chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1621                 status = chip->waitfunc(mtd, chip);
1622                 /*
1623                  * See if operation failed and additional status checks are
1624                  * available
1625                  */
1626                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
1627                         status = chip->errstat(mtd, chip, FL_WRITING, status,
1628                                                page);
1629
1630                 if (status & NAND_STATUS_FAIL)
1631                         return -EIO;
1632         } else {
1633                 chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
1634                 status = chip->waitfunc(mtd, chip);
1635         }
1636
1637 #ifdef CONFIG_MTD_NAND_VERIFY_WRITE
1638         /* Send command to read back the data */
1639         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1640
1641         if (chip->verify_buf(mtd, buf, mtd->writesize))
1642                 return -EIO;
1643 #endif
1644         return 0;
1645 }
1646
1647 /**
1648  * nand_fill_oob - [Internal] Transfer client buffer to oob
1649  * @chip:       nand chip structure
1650  * @oob:        oob data buffer
1651  * @ops:        oob ops structure
1652  */
1653 static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob,
1654                                   struct mtd_oob_ops *ops)
1655 {
1656         size_t len = ops->ooblen;
1657
1658         switch(ops->mode) {
1659
1660         case MTD_OOB_PLACE:
1661         case MTD_OOB_RAW:
1662                 memcpy(chip->oob_poi + ops->ooboffs, oob, len);
1663                 return oob + len;
1664
1665         case MTD_OOB_AUTO: {
1666                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
1667                 uint32_t boffs = 0, woffs = ops->ooboffs;
1668                 size_t bytes = 0;
1669
1670                 for(; free->length && len; free++, len -= bytes) {
1671                         /* Write request not from offset 0 ? */
1672                         if (unlikely(woffs)) {
1673                                 if (woffs >= free->length) {
1674                                         woffs -= free->length;
1675                                         continue;
1676                                 }
1677                                 boffs = free->offset + woffs;
1678                                 bytes = min_t(size_t, len,
1679                                               (free->length - woffs));
1680                                 woffs = 0;
1681                         } else {
1682                                 bytes = min_t(size_t, len, free->length);
1683                                 boffs = free->offset;
1684                         }
1685                         memcpy(chip->oob_poi + boffs, oob, bytes);
1686                         oob += bytes;
1687                 }
1688                 return oob;
1689         }
1690         default:
1691                 BUG();
1692         }
1693         return NULL;
1694 }
1695
1696 #define NOTALIGNED(x)   (x & (chip->subpagesize - 1)) != 0
1697
1698 /**
1699  * nand_do_write_ops - [Internal] NAND write with ECC
1700  * @mtd:        MTD device structure
1701  * @to:         offset to write to
1702  * @ops:        oob operations description structure
1703  *
1704  * NAND write with ECC
1705  */
1706 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
1707                              struct mtd_oob_ops *ops)
1708 {
1709         int chipnr, realpage, page, blockmask, column;
1710         struct nand_chip *chip = mtd->priv;
1711         uint32_t writelen = ops->len;
1712         uint8_t *oob = ops->oobbuf;
1713         uint8_t *buf = ops->datbuf;
1714         int ret, subpage;
1715
1716         ops->retlen = 0;
1717         if (!writelen)
1718                 return 0;
1719
1720         /* reject writes, which are not page aligned */
1721         if (NOTALIGNED(to) || NOTALIGNED(ops->len)) {
1722                 printk(KERN_NOTICE "nand_write: "
1723                        "Attempt to write not page aligned data\n");
1724                 return -EINVAL;
1725         }
1726
1727         column = to & (mtd->writesize - 1);
1728         subpage = column || (writelen & (mtd->writesize - 1));
1729
1730         if (subpage && oob)
1731                 return -EINVAL;
1732
1733         chipnr = (int)(to >> chip->chip_shift);
1734         chip->select_chip(mtd, chipnr);
1735
1736         /* Check, if it is write protected */
1737         if (nand_check_wp(mtd))
1738                 return -EIO;
1739
1740         realpage = (int)(to >> chip->page_shift);
1741         page = realpage & chip->pagemask;
1742         blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1743
1744         /* Invalidate the page cache, when we write to the cached page */
1745         if (to <= (chip->pagebuf << chip->page_shift) &&
1746             (chip->pagebuf << chip->page_shift) < (to + ops->len))
1747                 chip->pagebuf = -1;
1748
1749         /* If we're not given explicit OOB data, let it be 0xFF */
1750         if (likely(!oob))
1751                 memset(chip->oob_poi, 0xff, mtd->oobsize);
1752
1753         while(1) {
1754                 int bytes = mtd->writesize;
1755                 int cached = writelen > bytes && page != blockmask;
1756                 uint8_t *wbuf = buf;
1757
1758                 /* Partial page write ? */
1759                 if (unlikely(column || writelen < (mtd->writesize - 1))) {
1760                         cached = 0;
1761                         bytes = min_t(int, bytes - column, (int) writelen);
1762                         chip->pagebuf = -1;
1763                         memset(chip->buffers->databuf, 0xff, mtd->writesize);
1764                         memcpy(&chip->buffers->databuf[column], buf, bytes);
1765                         wbuf = chip->buffers->databuf;
1766                 }
1767
1768                 if (unlikely(oob))
1769                         oob = nand_fill_oob(chip, oob, ops);
1770
1771                 ret = chip->write_page(mtd, chip, wbuf, page, cached,
1772                                        (ops->mode == MTD_OOB_RAW));
1773                 if (ret)
1774                         break;
1775
1776                 writelen -= bytes;
1777                 if (!writelen)
1778                         break;
1779
1780                 column = 0;
1781                 buf += bytes;
1782                 realpage++;
1783
1784                 page = realpage & chip->pagemask;
1785                 /* Check, if we cross a chip boundary */
1786                 if (!page) {
1787                         chipnr++;
1788                         chip->select_chip(mtd, -1);
1789                         chip->select_chip(mtd, chipnr);
1790                 }
1791         }
1792
1793         ops->retlen = ops->len - writelen;
1794         if (unlikely(oob))
1795                 ops->oobretlen = ops->ooblen;
1796         return ret;
1797 }
1798
1799 /**
1800  * nand_write - [MTD Interface] NAND write with ECC
1801  * @mtd:        MTD device structure
1802  * @to:         offset to write to
1803  * @len:        number of bytes to write
1804  * @retlen:     pointer to variable to store the number of written bytes
1805  * @buf:        the data to write
1806  *
1807  * NAND write with ECC
1808  */
1809 static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
1810                           size_t *retlen, const uint8_t *buf)
1811 {
1812         struct nand_chip *chip = mtd->priv;
1813         int ret;
1814
1815         /* Do not allow reads past end of device */
1816         if ((to + len) > mtd->size)
1817                 return -EINVAL;
1818         if (!len)
1819                 return 0;
1820
1821         nand_get_device(chip, mtd, FL_WRITING);
1822
1823         chip->ops.len = len;
1824         chip->ops.datbuf = (uint8_t *)buf;
1825         chip->ops.oobbuf = NULL;
1826
1827         ret = nand_do_write_ops(mtd, to, &chip->ops);
1828
1829         *retlen = chip->ops.retlen;
1830
1831         nand_release_device(mtd);
1832
1833         return ret;
1834 }
1835
1836 /**
1837  * nand_do_write_oob - [MTD Interface] NAND write out-of-band
1838  * @mtd:        MTD device structure
1839  * @to:         offset to write to
1840  * @ops:        oob operation description structure
1841  *
1842  * NAND write out-of-band
1843  */
1844 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
1845                              struct mtd_oob_ops *ops)
1846 {
1847         int chipnr, page, status, len;
1848         struct nand_chip *chip = mtd->priv;
1849
1850         DEBUG(MTD_DEBUG_LEVEL3, "nand_write_oob: to = 0x%08x, len = %i\n",
1851               (unsigned int)to, (int)ops->ooblen);
1852
1853         if (ops->mode == MTD_OOB_AUTO)
1854                 len = chip->ecc.layout->oobavail;
1855         else
1856                 len = mtd->oobsize;
1857
1858         /* Do not allow write past end of page */
1859         if ((ops->ooboffs + ops->ooblen) > len) {
1860                 DEBUG(MTD_DEBUG_LEVEL0, "nand_write_oob: "
1861                       "Attempt to write past end of page\n");
1862                 return -EINVAL;
1863         }
1864
1865         if (unlikely(ops->ooboffs >= len)) {
1866                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1867                         "Attempt to start write outside oob\n");
1868                 return -EINVAL;
1869         }
1870
1871         /* Do not allow reads past end of device */
1872         if (unlikely(to >= mtd->size ||
1873                      ops->ooboffs + ops->ooblen >
1874                         ((mtd->size >> chip->page_shift) -
1875                          (to >> chip->page_shift)) * len)) {
1876                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1877                         "Attempt write beyond end of device\n");
1878                 return -EINVAL;
1879         }
1880
1881         chipnr = (int)(to >> chip->chip_shift);
1882         chip->select_chip(mtd, chipnr);
1883
1884         /* Shift to get page */
1885         page = (int)(to >> chip->page_shift);
1886
1887         /*
1888          * Reset the chip. Some chips (like the Toshiba TC5832DC found in one
1889          * of my DiskOnChip 2000 test units) will clear the whole data page too
1890          * if we don't do this. I have no clue why, but I seem to have 'fixed'
1891          * it in the doc2000 driver in August 1999.  dwmw2.
1892          */
1893         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
1894
1895         /* Check, if it is write protected */
1896         if (nand_check_wp(mtd))
1897                 return -EROFS;
1898
1899         /* Invalidate the page cache, if we write to the cached page */
1900         if (page == chip->pagebuf)
1901                 chip->pagebuf = -1;
1902
1903         memset(chip->oob_poi, 0xff, mtd->oobsize);
1904         nand_fill_oob(chip, ops->oobbuf, ops);
1905         status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
1906         memset(chip->oob_poi, 0xff, mtd->oobsize);
1907
1908         if (status)
1909                 return status;
1910
1911         ops->oobretlen = ops->ooblen;
1912
1913         return 0;
1914 }
1915
1916 /**
1917  * nand_write_oob - [MTD Interface] NAND write data and/or out-of-band
1918  * @mtd:        MTD device structure
1919  * @to:         offset to write to
1920  * @ops:        oob operation description structure
1921  */
1922 static int nand_write_oob(struct mtd_info *mtd, loff_t to,
1923                           struct mtd_oob_ops *ops)
1924 {
1925         struct nand_chip *chip = mtd->priv;
1926         int ret = -ENOTSUPP;
1927
1928         ops->retlen = 0;
1929
1930         /* Do not allow writes past end of device */
1931         if (ops->datbuf && (to + ops->len) > mtd->size) {
1932                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1933                       "Attempt read beyond end of device\n");
1934                 return -EINVAL;
1935         }
1936
1937         nand_get_device(chip, mtd, FL_WRITING);
1938
1939         switch(ops->mode) {
1940         case MTD_OOB_PLACE:
1941         case MTD_OOB_AUTO:
1942         case MTD_OOB_RAW:
1943                 break;
1944
1945         default:
1946                 goto out;
1947         }
1948
1949         if (!ops->datbuf)
1950                 ret = nand_do_write_oob(mtd, to, ops);
1951         else
1952                 ret = nand_do_write_ops(mtd, to, ops);
1953
1954  out:
1955         nand_release_device(mtd);
1956         return ret;
1957 }
1958
1959 /**
1960  * single_erease_cmd - [GENERIC] NAND standard block erase command function
1961  * @mtd:        MTD device structure
1962  * @page:       the page address of the block which will be erased
1963  *
1964  * Standard erase command for NAND chips
1965  */
1966 static void single_erase_cmd(struct mtd_info *mtd, int page)
1967 {
1968         struct nand_chip *chip = mtd->priv;
1969         /* Send commands to erase a block */
1970         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
1971         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
1972 }
1973
1974 /**
1975  * multi_erease_cmd - [GENERIC] AND specific block erase command function
1976  * @mtd:        MTD device structure
1977  * @page:       the page address of the block which will be erased
1978  *
1979  * AND multi block erase command function
1980  * Erase 4 consecutive blocks
1981  */
1982 static void multi_erase_cmd(struct mtd_info *mtd, int page)
1983 {
1984         struct nand_chip *chip = mtd->priv;
1985         /* Send commands to erase a block */
1986         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1987         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1988         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1989         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
1990         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
1991 }
1992
1993 /**
1994  * nand_erase - [MTD Interface] erase block(s)
1995  * @mtd:        MTD device structure
1996  * @instr:      erase instruction
1997  *
1998  * Erase one ore more blocks
1999  */
2000 static int nand_erase(struct mtd_info *mtd, struct erase_info *instr)
2001 {
2002         return nand_erase_nand(mtd, instr, 0);
2003 }
2004
2005 #define BBT_PAGE_MASK   0xffffff3f
2006 /**
2007  * nand_erase_nand - [Internal] erase block(s)
2008  * @mtd:        MTD device structure
2009  * @instr:      erase instruction
2010  * @allowbbt:   allow erasing the bbt area
2011  *
2012  * Erase one ore more blocks
2013  */
2014 int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
2015                     int allowbbt)
2016 {
2017         int page, len, status, pages_per_block, ret, chipnr;
2018         struct nand_chip *chip = mtd->priv;
2019         int rewrite_bbt[NAND_MAX_CHIPS]={0};
2020         unsigned int bbt_masked_page = 0xffffffff;
2021
2022         DEBUG(MTD_DEBUG_LEVEL3, "nand_erase: start = 0x%08x, len = %i\n",
2023               (unsigned int)instr->addr, (unsigned int)instr->len);
2024
2025         /* Start address must align on block boundary */
2026         if (instr->addr & ((1 << chip->phys_erase_shift) - 1)) {
2027                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: Unaligned address\n");
2028                 return -EINVAL;
2029         }
2030
2031         /* Length must align on block boundary */
2032         if (instr->len & ((1 << chip->phys_erase_shift) - 1)) {
2033                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
2034                       "Length not block aligned\n");
2035                 return -EINVAL;
2036         }
2037
2038         /* Do not allow erase past end of device */
2039         if ((instr->len + instr->addr) > mtd->size) {
2040                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
2041                       "Erase past end of device\n");
2042                 return -EINVAL;
2043         }
2044
2045         instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
2046
2047         /* Grab the lock and see if the device is available */
2048         nand_get_device(chip, mtd, FL_ERASING);
2049
2050         /* Shift to get first page */
2051         page = (int)(instr->addr >> chip->page_shift);
2052         chipnr = (int)(instr->addr >> chip->chip_shift);
2053
2054         /* Calculate pages in each block */
2055         pages_per_block = 1 << (chip->phys_erase_shift - chip->page_shift);
2056
2057         /* Select the NAND device */
2058         chip->select_chip(mtd, chipnr);
2059
2060         /* Check, if it is write protected */
2061         if (nand_check_wp(mtd)) {
2062                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
2063                       "Device is write protected!!!\n");
2064                 instr->state = MTD_ERASE_FAILED;
2065                 goto erase_exit;
2066         }
2067
2068         /*
2069          * If BBT requires refresh, set the BBT page mask to see if the BBT
2070          * should be rewritten. Otherwise the mask is set to 0xffffffff which
2071          * can not be matched. This is also done when the bbt is actually
2072          * erased to avoid recusrsive updates
2073          */
2074         if (chip->options & BBT_AUTO_REFRESH && !allowbbt)
2075                 bbt_masked_page = chip->bbt_td->pages[chipnr] & BBT_PAGE_MASK;
2076
2077         /* Loop through the pages */
2078         len = instr->len;
2079
2080         instr->state = MTD_ERASING;
2081
2082         while (len) {
2083                 /*
2084                  * heck if we have a bad block, we do not erase bad blocks !
2085                  */
2086                 if (nand_block_checkbad(mtd, ((loff_t) page) <<
2087                                         chip->page_shift, 0, allowbbt)) {
2088                         printk(KERN_WARNING "nand_erase: attempt to erase a "
2089                                "bad block at page 0x%08x\n", page);
2090                         instr->state = MTD_ERASE_FAILED;
2091                         goto erase_exit;
2092                 }
2093
2094                 /*
2095                  * Invalidate the page cache, if we erase the block which
2096                  * contains the current cached page
2097                  */
2098                 if (page <= chip->pagebuf && chip->pagebuf <
2099                     (page + pages_per_block))
2100                         chip->pagebuf = -1;
2101
2102                 chip->erase_cmd(mtd, page & chip->pagemask);
2103
2104                 status = chip->waitfunc(mtd, chip);
2105
2106                 /*
2107                  * See if operation failed and additional status checks are
2108                  * available
2109                  */
2110                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2111                         status = chip->errstat(mtd, chip, FL_ERASING,
2112                                                status, page);
2113
2114                 /* See if block erase succeeded */
2115                 if (status & NAND_STATUS_FAIL) {
2116                         DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
2117                               "Failed erase, page 0x%08x\n", page);
2118                         instr->state = MTD_ERASE_FAILED;
2119                         instr->fail_addr = (page << chip->page_shift);
2120                         goto erase_exit;
2121                 }
2122
2123                 /*
2124                  * If BBT requires refresh, set the BBT rewrite flag to the
2125                  * page being erased
2126                  */
2127                 if (bbt_masked_page != 0xffffffff &&
2128                     (page & BBT_PAGE_MASK) == bbt_masked_page)
2129                             rewrite_bbt[chipnr] = (page << chip->page_shift);
2130
2131                 /* Increment page address and decrement length */
2132                 len -= (1 << chip->phys_erase_shift);
2133                 page += pages_per_block;
2134
2135                 /* Check, if we cross a chip boundary */
2136                 if (len && !(page & chip->pagemask)) {
2137                         chipnr++;
2138                         chip->select_chip(mtd, -1);
2139                         chip->select_chip(mtd, chipnr);
2140
2141                         /*
2142                          * If BBT requires refresh and BBT-PERCHIP, set the BBT
2143                          * page mask to see if this BBT should be rewritten
2144                          */
2145                         if (bbt_masked_page != 0xffffffff &&
2146                             (chip->bbt_td->options & NAND_BBT_PERCHIP))
2147                                 bbt_masked_page = chip->bbt_td->pages[chipnr] &
2148                                         BBT_PAGE_MASK;
2149                 }
2150         }
2151         instr->state = MTD_ERASE_DONE;
2152
2153  erase_exit:
2154
2155         ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
2156
2157         /* Deselect and wake up anyone waiting on the device */
2158         nand_release_device(mtd);
2159
2160         /* Do call back function */
2161         if (!ret)
2162                 mtd_erase_callback(instr);
2163
2164         /*
2165          * If BBT requires refresh and erase was successful, rewrite any
2166          * selected bad block tables
2167          */
2168         if (bbt_masked_page == 0xffffffff || ret)
2169                 return ret;
2170
2171         for (chipnr = 0; chipnr < chip->numchips; chipnr++) {
2172                 if (!rewrite_bbt[chipnr])
2173                         continue;
2174                 /* update the BBT for chip */
2175                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase_nand: nand_update_bbt "
2176                       "(%d:0x%0x 0x%0x)\n", chipnr, rewrite_bbt[chipnr],
2177                       chip->bbt_td->pages[chipnr]);
2178                 nand_update_bbt(mtd, rewrite_bbt[chipnr]);
2179         }
2180
2181         /* Return more or less happy */
2182         return ret;
2183 }
2184
2185 /**
2186  * nand_sync - [MTD Interface] sync
2187  * @mtd:        MTD device structure
2188  *
2189  * Sync is actually a wait for chip ready function
2190  */
2191 static void nand_sync(struct mtd_info *mtd)
2192 {
2193         struct nand_chip *chip = mtd->priv;
2194
2195         DEBUG(MTD_DEBUG_LEVEL3, "nand_sync: called\n");
2196
2197         /* Grab the lock and see if the device is available */
2198         nand_get_device(chip, mtd, FL_SYNCING);
2199         /* Release it and go back */
2200         nand_release_device(mtd);
2201 }
2202
2203 /**
2204  * nand_block_isbad - [MTD Interface] Check if block at offset is bad
2205  * @mtd:        MTD device structure
2206  * @offs:       offset relative to mtd start
2207  */
2208 static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
2209 {
2210         /* Check for invalid offset */
2211         if (offs > mtd->size)
2212                 return -EINVAL;
2213
2214         return nand_block_checkbad(mtd, offs, 1, 0);
2215 }
2216
2217 /**
2218  * nand_block_markbad - [MTD Interface] Mark block at the given offset as bad
2219  * @mtd:        MTD device structure
2220  * @ofs:        offset relative to mtd start
2221  */
2222 static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
2223 {
2224         struct nand_chip *chip = mtd->priv;
2225         int ret;
2226
2227         if ((ret = nand_block_isbad(mtd, ofs))) {
2228                 /* If it was bad already, return success and do nothing. */
2229                 if (ret > 0)
2230                         return 0;
2231                 return ret;
2232         }
2233
2234         return chip->block_markbad(mtd, ofs);
2235 }
2236
2237 /**
2238  * nand_suspend - [MTD Interface] Suspend the NAND flash
2239  * @mtd:        MTD device structure
2240  */
2241 static int nand_suspend(struct mtd_info *mtd)
2242 {
2243         struct nand_chip *chip = mtd->priv;
2244
2245         return nand_get_device(chip, mtd, FL_PM_SUSPENDED);
2246 }
2247
2248 /**
2249  * nand_resume - [MTD Interface] Resume the NAND flash
2250  * @mtd:        MTD device structure
2251  */
2252 static void nand_resume(struct mtd_info *mtd)
2253 {
2254         struct nand_chip *chip = mtd->priv;
2255
2256         if (chip->state == FL_PM_SUSPENDED)
2257                 nand_release_device(mtd);
2258         else
2259                 printk(KERN_ERR "nand_resume() called for a chip which is not "
2260                        "in suspended state\n");
2261 }
2262
2263 /*
2264  * Set default functions
2265  */
2266 static void nand_set_defaults(struct nand_chip *chip, int busw)
2267 {
2268         /* check for proper chip_delay setup, set 20us if not */
2269         if (!chip->chip_delay)
2270                 chip->chip_delay = 20;
2271
2272         /* check, if a user supplied command function given */
2273         if (chip->cmdfunc == NULL)
2274                 chip->cmdfunc = nand_command;
2275
2276         /* check, if a user supplied wait function given */
2277         if (chip->waitfunc == NULL)
2278                 chip->waitfunc = nand_wait;
2279
2280         if (!chip->select_chip)
2281                 chip->select_chip = nand_select_chip;
2282         if (!chip->read_byte)
2283                 chip->read_byte = busw ? nand_read_byte16 : nand_read_byte;
2284         if (!chip->read_word)
2285                 chip->read_word = nand_read_word;
2286         if (!chip->block_bad)
2287                 chip->block_bad = nand_block_bad;
2288         if (!chip->block_markbad)
2289                 chip->block_markbad = nand_default_block_markbad;
2290         if (!chip->write_buf)
2291                 chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
2292         if (!chip->read_buf)
2293                 chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
2294         if (!chip->verify_buf)
2295                 chip->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf;
2296         if (!chip->scan_bbt)
2297                 chip->scan_bbt = nand_default_bbt;
2298
2299         if (!chip->controller) {
2300                 chip->controller = &chip->hwcontrol;
2301                 spin_lock_init(&chip->controller->lock);
2302                 init_waitqueue_head(&chip->controller->wq);
2303         }
2304
2305 }
2306
2307 /*
2308  * Get the flash and manufacturer id and lookup if the type is supported
2309  */
2310 static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
2311                                                   struct nand_chip *chip,
2312                                                   int busw, int *maf_id)
2313 {
2314         struct nand_flash_dev *type = NULL;
2315         int i, dev_id, maf_idx;
2316         int tmp_id, tmp_manf;
2317
2318         /* Select the device */
2319         chip->select_chip(mtd, 0);
2320
2321         /*
2322          * Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx)
2323          * after power-up
2324          */
2325         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
2326
2327         /* Send the command for reading device ID */
2328         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2329
2330         /* Read manufacturer and device IDs */
2331         *maf_id = chip->read_byte(mtd);
2332         dev_id = chip->read_byte(mtd);
2333
2334         /* Try again to make sure, as some systems the bus-hold or other
2335          * interface concerns can cause random data which looks like a
2336          * possibly credible NAND flash to appear. If the two results do
2337          * not match, ignore the device completely.
2338          */
2339
2340         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2341
2342         /* Read manufacturer and device IDs */
2343
2344         tmp_manf = chip->read_byte(mtd);
2345         tmp_id = chip->read_byte(mtd);
2346
2347         if (tmp_manf != *maf_id || tmp_id != dev_id) {
2348                 printk(KERN_INFO "%s: second ID read did not match "
2349                        "%02x,%02x against %02x,%02x\n", __func__,
2350                        *maf_id, dev_id, tmp_manf, tmp_id);
2351                 return ERR_PTR(-ENODEV);
2352         }
2353
2354         /* Lookup the flash id */
2355         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
2356                 if (dev_id == nand_flash_ids[i].id) {
2357                         type =  &nand_flash_ids[i];
2358                         break;
2359                 }
2360         }
2361
2362         if (!type)
2363                 return ERR_PTR(-ENODEV);
2364
2365         if (!mtd->name)
2366                 mtd->name = type->name;
2367
2368         chip->chipsize = type->chipsize << 20;
2369
2370         /* Newer devices have all the information in additional id bytes */
2371         if (!type->pagesize) {
2372                 int extid;
2373                 /* The 3rd id byte holds MLC / multichip data */
2374                 chip->cellinfo = chip->read_byte(mtd);
2375                 /* The 4th id byte is the important one */
2376                 extid = chip->read_byte(mtd);
2377                 /* Calc pagesize */
2378                 mtd->writesize = 1024 << (extid & 0x3);
2379                 extid >>= 2;
2380                 /* Calc oobsize */
2381                 mtd->oobsize = (8 << (extid & 0x01)) * (mtd->writesize >> 9);
2382                 extid >>= 2;
2383                 /* Calc blocksize. Blocksize is multiples of 64KiB */
2384                 mtd->erasesize = (64 * 1024) << (extid & 0x03);
2385                 extid >>= 2;
2386                 /* Get buswidth information */
2387                 busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
2388
2389         } else {
2390                 /*
2391                  * Old devices have chip data hardcoded in the device id table
2392                  */
2393                 mtd->erasesize = type->erasesize;
2394                 mtd->writesize = type->pagesize;
2395                 mtd->oobsize = mtd->writesize / 32;
2396                 busw = type->options & NAND_BUSWIDTH_16;
2397         }
2398
2399         /* Try to identify manufacturer */
2400         for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_idx++) {
2401                 if (nand_manuf_ids[maf_idx].id == *maf_id)
2402                         break;
2403         }
2404
2405         /*
2406          * Check, if buswidth is correct. Hardware drivers should set
2407          * chip correct !
2408          */
2409         if (busw != (chip->options & NAND_BUSWIDTH_16)) {
2410                 printk(KERN_INFO "NAND device: Manufacturer ID:"
2411                        " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id,
2412                        dev_id, nand_manuf_ids[maf_idx].name, mtd->name);
2413                 printk(KERN_WARNING "NAND bus width %d instead %d bit\n",
2414                        (chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
2415                        busw ? 16 : 8);
2416                 return ERR_PTR(-EINVAL);
2417         }
2418
2419         /* Calculate the address shift from the page size */
2420         chip->page_shift = ffs(mtd->writesize) - 1;
2421         /* Convert chipsize to number of pages per chip -1. */
2422         chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2423
2424         chip->bbt_erase_shift = chip->phys_erase_shift =
2425                 ffs(mtd->erasesize) - 1;
2426         chip->chip_shift = ffs(chip->chipsize) - 1;
2427
2428         /* Set the bad block position */
2429         chip->badblockpos = mtd->writesize > 512 ?
2430                 NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS;
2431
2432         /* Get chip options, preserve non chip based options */
2433         chip->options &= ~NAND_CHIPOPTIONS_MSK;
2434         chip->options |= type->options & NAND_CHIPOPTIONS_MSK;
2435
2436         /*
2437          * Set chip as a default. Board drivers can override it, if necessary
2438          */
2439         chip->options |= NAND_NO_AUTOINCR;
2440
2441         /* Check if chip is a not a samsung device. Do not clear the
2442          * options for chips which are not having an extended id.
2443          */
2444         if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
2445                 chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
2446
2447         /* Check for AND chips with 4 page planes */
2448         if (chip->options & NAND_4PAGE_ARRAY)
2449                 chip->erase_cmd = multi_erase_cmd;
2450         else
2451                 chip->erase_cmd = single_erase_cmd;
2452
2453         /* Do not replace user supplied command function ! */
2454         if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
2455                 chip->cmdfunc = nand_command_lp;
2456
2457         printk(KERN_INFO "NAND device: Manufacturer ID:"
2458                " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id, dev_id,
2459                nand_manuf_ids[maf_idx].name, type->name);
2460
2461         return type;
2462 }
2463
2464 /**
2465  * nand_scan_ident - [NAND Interface] Scan for the NAND device
2466  * @mtd:             MTD device structure
2467  * @maxchips:        Number of chips to scan for
2468  *
2469  * This is the first phase of the normal nand_scan() function. It
2470  * reads the flash ID and sets up MTD fields accordingly.
2471  *
2472  * The mtd->owner field must be set to the module of the caller.
2473  */
2474 int nand_scan_ident(struct mtd_info *mtd, int maxchips)
2475 {
2476         int i, busw, nand_maf_id;
2477         struct nand_chip *chip = mtd->priv;
2478         struct nand_flash_dev *type;
2479
2480         /* Get buswidth to select the correct functions */
2481         busw = chip->options & NAND_BUSWIDTH_16;
2482         /* Set the default functions */
2483         nand_set_defaults(chip, busw);
2484
2485         /* Read the flash type */
2486         type = nand_get_flash_type(mtd, chip, busw, &nand_maf_id);
2487
2488         if (IS_ERR(type)) {
2489                 printk(KERN_WARNING "No NAND device found!!!\n");
2490                 chip->select_chip(mtd, -1);
2491                 return PTR_ERR(type);
2492         }
2493
2494         /* Check for a chip array */
2495         for (i = 1; i < maxchips; i++) {
2496                 chip->select_chip(mtd, i);
2497                 /* See comment in nand_get_flash_type for reset */
2498                 chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
2499                 /* Send the command for reading device ID */
2500                 chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2501                 /* Read manufacturer and device IDs */
2502                 if (nand_maf_id != chip->read_byte(mtd) ||
2503                     type->id != chip->read_byte(mtd))
2504                         break;
2505         }
2506         if (i > 1)
2507                 printk(KERN_INFO "%d NAND chips detected\n", i);
2508
2509         /* Store the number of chips and calc total size for mtd */
2510         chip->numchips = i;
2511         mtd->size = i * chip->chipsize;
2512
2513         return 0;
2514 }
2515
2516
2517 /**
2518  * nand_scan_tail - [NAND Interface] Scan for the NAND device
2519  * @mtd:            MTD device structure
2520  * @maxchips:       Number of chips to scan for
2521  *
2522  * This is the second phase of the normal nand_scan() function. It
2523  * fills out all the uninitialized function pointers with the defaults
2524  * and scans for a bad block table if appropriate.
2525  */
2526 int nand_scan_tail(struct mtd_info *mtd)
2527 {
2528         int i;
2529         struct nand_chip *chip = mtd->priv;
2530
2531         if (!(chip->options & NAND_OWN_BUFFERS))
2532                 chip->buffers = kmalloc(sizeof(*chip->buffers), GFP_KERNEL);
2533         if (!chip->buffers)
2534                 return -ENOMEM;
2535
2536         /* Set the internal oob buffer location, just after the page data */
2537         chip->oob_poi = chip->buffers->databuf + mtd->writesize;
2538
2539         /*
2540          * If no default placement scheme is given, select an appropriate one
2541          */
2542         if (!chip->ecc.layout) {
2543                 switch (mtd->oobsize) {
2544                 case 8:
2545                         chip->ecc.layout = &nand_oob_8;
2546                         break;
2547                 case 16:
2548                         chip->ecc.layout = &nand_oob_16;
2549                         break;
2550                 case 64:
2551                         chip->ecc.layout = &nand_oob_64;
2552                         break;
2553                 default:
2554                         printk(KERN_WARNING "No oob scheme defined for "
2555                                "oobsize %d\n", mtd->oobsize);
2556                         BUG();
2557                 }
2558         }
2559
2560         if (!chip->write_page)
2561                 chip->write_page = nand_write_page;
2562
2563         /*
2564          * check ECC mode, default to software if 3byte/512byte hardware ECC is
2565          * selected and we have 256 byte pagesize fallback to software ECC
2566          */
2567         if (!chip->ecc.read_page_raw)
2568                 chip->ecc.read_page_raw = nand_read_page_raw;
2569         if (!chip->ecc.write_page_raw)
2570                 chip->ecc.write_page_raw = nand_write_page_raw;
2571
2572         switch (chip->ecc.mode) {
2573         case NAND_ECC_HW:
2574                 /* Use standard hwecc read page function ? */
2575                 if (!chip->ecc.read_page)
2576                         chip->ecc.read_page = nand_read_page_hwecc;
2577                 if (!chip->ecc.write_page)
2578                         chip->ecc.write_page = nand_write_page_hwecc;
2579                 if (!chip->ecc.read_oob)
2580                         chip->ecc.read_oob = nand_read_oob_std;
2581                 if (!chip->ecc.write_oob)
2582                         chip->ecc.write_oob = nand_write_oob_std;
2583
2584         case NAND_ECC_HW_SYNDROME:
2585                 if ((!chip->ecc.calculate || !chip->ecc.correct ||
2586                      !chip->ecc.hwctl) &&
2587                     (!chip->ecc.read_page ||
2588                      chip->ecc.read_page == nand_read_page_hwecc ||
2589                      !chip->ecc.write_page ||
2590                      chip->ecc.write_page == nand_write_page_hwecc)) {
2591                         printk(KERN_WARNING "No ECC functions supplied, "
2592                                "Hardware ECC not possible\n");
2593                         BUG();
2594                 }
2595                 /* Use standard syndrome read/write page function ? */
2596                 if (!chip->ecc.read_page)
2597                         chip->ecc.read_page = nand_read_page_syndrome;
2598                 if (!chip->ecc.write_page)
2599                         chip->ecc.write_page = nand_write_page_syndrome;
2600                 if (!chip->ecc.read_oob)
2601                         chip->ecc.read_oob = nand_read_oob_syndrome;
2602                 if (!chip->ecc.write_oob)
2603                         chip->ecc.write_oob = nand_write_oob_syndrome;
2604
2605                 if (mtd->writesize >= chip->ecc.size)
2606                         break;
2607                 printk(KERN_WARNING "%d byte HW ECC not possible on "
2608                        "%d byte page size, fallback to SW ECC\n",
2609                        chip->ecc.size, mtd->writesize);
2610                 chip->ecc.mode = NAND_ECC_SOFT;
2611
2612         case NAND_ECC_SOFT:
2613                 chip->ecc.calculate = nand_calculate_ecc;
2614                 chip->ecc.correct = nand_correct_data;
2615                 chip->ecc.read_page = nand_read_page_swecc;
2616                 chip->ecc.read_subpage = nand_read_subpage;
2617                 chip->ecc.write_page = nand_write_page_swecc;
2618                 chip->ecc.read_oob = nand_read_oob_std;
2619                 chip->ecc.write_oob = nand_write_oob_std;
2620                 chip->ecc.size = 256;
2621                 chip->ecc.bytes = 3;
2622                 break;
2623
2624         case NAND_ECC_NONE:
2625                 printk(KERN_WARNING "NAND_ECC_NONE selected by board driver. "
2626                        "This is not recommended !!\n");
2627                 chip->ecc.read_page = nand_read_page_raw;
2628                 chip->ecc.write_page = nand_write_page_raw;
2629                 chip->ecc.read_oob = nand_read_oob_std;
2630                 chip->ecc.write_oob = nand_write_oob_std;
2631                 chip->ecc.size = mtd->writesize;
2632                 chip->ecc.bytes = 0;
2633                 break;
2634
2635         default:
2636                 printk(KERN_WARNING "Invalid NAND_ECC_MODE %d\n",
2637                        chip->ecc.mode);
2638                 BUG();
2639         }
2640
2641         /*
2642          * The number of bytes available for a client to place data into
2643          * the out of band area
2644          */
2645         chip->ecc.layout->oobavail = 0;
2646         for (i = 0; chip->ecc.layout->oobfree[i].length; i++)
2647                 chip->ecc.layout->oobavail +=
2648                         chip->ecc.layout->oobfree[i].length;
2649         mtd->oobavail = chip->ecc.layout->oobavail;
2650
2651         /*
2652          * Set the number of read / write steps for one page depending on ECC
2653          * mode
2654          */
2655         chip->ecc.steps = mtd->writesize / chip->ecc.size;
2656         if(chip->ecc.steps * chip->ecc.size != mtd->writesize) {
2657                 printk(KERN_WARNING "Invalid ecc parameters\n");
2658                 BUG();
2659         }
2660         chip->ecc.total = chip->ecc.steps * chip->ecc.bytes;
2661
2662         /*
2663          * Allow subpage writes up to ecc.steps. Not possible for MLC
2664          * FLASH.
2665          */
2666         if (!(chip->options & NAND_NO_SUBPAGE_WRITE) &&
2667             !(chip->cellinfo & NAND_CI_CELLTYPE_MSK)) {
2668                 switch(chip->ecc.steps) {
2669                 case 2:
2670                         mtd->subpage_sft = 1;
2671                         break;
2672                 case 4:
2673                 case 8:
2674                         mtd->subpage_sft = 2;
2675                         break;
2676                 }
2677         }
2678         chip->subpagesize = mtd->writesize >> mtd->subpage_sft;
2679
2680         /* Initialize state */
2681         chip->state = FL_READY;
2682
2683         /* De-select the device */
2684         chip->select_chip(mtd, -1);
2685
2686         /* Invalidate the pagebuffer reference */
2687         chip->pagebuf = -1;
2688
2689         /* Fill in remaining MTD driver data */
2690         mtd->type = MTD_NANDFLASH;
2691         mtd->flags = MTD_CAP_NANDFLASH;
2692         mtd->erase = nand_erase;
2693         mtd->point = NULL;
2694         mtd->unpoint = NULL;
2695         mtd->read = nand_read;
2696         mtd->write = nand_write;
2697         mtd->read_oob = nand_read_oob;
2698         mtd->write_oob = nand_write_oob;
2699         mtd->sync = nand_sync;
2700         mtd->lock = NULL;
2701         mtd->unlock = NULL;
2702         mtd->suspend = nand_suspend;
2703         mtd->resume = nand_resume;
2704         mtd->block_isbad = nand_block_isbad;
2705         mtd->block_markbad = nand_block_markbad;
2706
2707         /* propagate ecc.layout to mtd_info */
2708         mtd->ecclayout = chip->ecc.layout;
2709
2710         /* Check, if we should skip the bad block table scan */
2711         if (chip->options & NAND_SKIP_BBTSCAN)
2712                 return 0;
2713
2714         /* Build bad block table */
2715         return chip->scan_bbt(mtd);
2716 }
2717
2718 /* module_text_address() isn't exported, and it's mostly a pointless
2719    test if this is a module _anyway_ -- they'd have to try _really_ hard
2720    to call us from in-kernel code if the core NAND support is modular. */
2721 #ifdef MODULE
2722 #define caller_is_module() (1)
2723 #else
2724 #define caller_is_module() \
2725         module_text_address((unsigned long)__builtin_return_address(0))
2726 #endif
2727
2728 /**
2729  * nand_scan - [NAND Interface] Scan for the NAND device
2730  * @mtd:        MTD device structure
2731  * @maxchips:   Number of chips to scan for
2732  *
2733  * This fills out all the uninitialized function pointers
2734  * with the defaults.
2735  * The flash ID is read and the mtd/chip structures are
2736  * filled with the appropriate values.
2737  * The mtd->owner field must be set to the module of the caller
2738  *
2739  */
2740 int nand_scan(struct mtd_info *mtd, int maxchips)
2741 {
2742         int ret;
2743
2744         /* Many callers got this wrong, so check for it for a while... */
2745         if (!mtd->owner && caller_is_module()) {
2746                 printk(KERN_CRIT "nand_scan() called with NULL mtd->owner!\n");
2747                 BUG();
2748         }
2749
2750         ret = nand_scan_ident(mtd, maxchips);
2751         if (!ret)
2752                 ret = nand_scan_tail(mtd);
2753         return ret;
2754 }
2755
2756 /**
2757  * nand_release - [NAND Interface] Free resources held by the NAND device
2758  * @mtd:        MTD device structure
2759 */
2760 void nand_release(struct mtd_info *mtd)
2761 {
2762         struct nand_chip *chip = mtd->priv;
2763
2764 #ifdef CONFIG_MTD_PARTITIONS
2765         /* Deregister partitions */
2766         del_mtd_partitions(mtd);
2767 #endif
2768         /* Deregister the device */
2769         del_mtd_device(mtd);
2770
2771         /* Free bad block table memory */
2772         kfree(chip->bbt);
2773         if (!(chip->options & NAND_OWN_BUFFERS))
2774                 kfree(chip->buffers);
2775 }
2776
2777 EXPORT_SYMBOL_GPL(nand_scan);
2778 EXPORT_SYMBOL_GPL(nand_scan_ident);
2779 EXPORT_SYMBOL_GPL(nand_scan_tail);
2780 EXPORT_SYMBOL_GPL(nand_release);
2781
2782 static int __init nand_base_init(void)
2783 {
2784         led_trigger_register_simple("nand-disk", &nand_led_trigger);
2785         return 0;
2786 }
2787
2788 static void __exit nand_base_exit(void)
2789 {
2790         led_trigger_unregister_simple(nand_led_trigger);
2791 }
2792
2793 module_init(nand_base_init);
2794 module_exit(nand_base_exit);
2795
2796 MODULE_LICENSE("GPL");
2797 MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>, Thomas Gleixner <tglx@linutronix.de>");
2798 MODULE_DESCRIPTION("Generic NAND flash driver code");