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_page_hwecc - [REPLACABLE] hardware ecc based page read function
 802  * @mtd:        mtd info structure
 803  * @chip:       nand chip info structure
 804  * @buf:        buffer to store read data
 805  *
 806  * Not for syndrome calculating ecc controllers which need a special oob layout
 807  */
 808 static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
 809                                 uint8_t *buf)
 810 {
 811         int i, eccsize = chip->ecc.size;
 812         int eccbytes = chip->ecc.bytes;
 813         int eccsteps = chip->ecc.steps;
 814         uint8_t *p = buf;
 815         uint8_t *ecc_calc = chip->buffers->ecccalc;
 816         uint8_t *ecc_code = chip->buffers->ecccode;
 817         uint32_t *eccpos = chip->ecc.layout->eccpos;
 818
 819         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 820                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
 821                 chip->read_buf(mtd, p, eccsize);
 822                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
 823         }
 824         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
 825
 826         for (i = 0; i < chip->ecc.total; i++)
 827                 ecc_code[i] = chip->oob_poi[eccpos[i]];
 828
 829         eccsteps = chip->ecc.steps;
 830         p = buf;
 831
 832         for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 833                 int stat;
 834
 835                 stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
 836                 if (stat < 0)
 837                         mtd->ecc_stats.failed++;
 838                 else
 839                         mtd->ecc_stats.corrected += stat;
 840         }
 841         return 0;
 842 }
 843
 844 /**
 845  * nand_read_page_syndrome - [REPLACABLE] hardware ecc syndrom based page read
 846  * @mtd:        mtd info structure
 847  * @chip:       nand chip info structure
 848  * @buf:        buffer to store read data
 849  *
 850  * The hw generator calculates the error syndrome automatically. Therefor
 851  * we need a special oob layout and handling.
 852  */
 853 static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
 854                                    uint8_t *buf)
 855 {
 856         int i, eccsize = chip->ecc.size;
 857         int eccbytes = chip->ecc.bytes;
 858         int eccsteps = chip->ecc.steps;
 859         uint8_t *p = buf;
 860         uint8_t *oob = chip->oob_poi;
 861
 862         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 863                 int stat;
 864
 865                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
 866                 chip->read_buf(mtd, p, eccsize);
 867
 868                 if (chip->ecc.prepad) {
 869                         chip->read_buf(mtd, oob, chip->ecc.prepad);
 870                         oob += chip->ecc.prepad;
 871                 }
 872
 873                 chip->ecc.hwctl(mtd, NAND_ECC_READSYN);
 874                 chip->read_buf(mtd, oob, eccbytes);
 875                 stat = chip->ecc.correct(mtd, p, oob, NULL);
 876
 877                 if (stat < 0)
 878                         mtd->ecc_stats.failed++;
 879                 else
 880                         mtd->ecc_stats.corrected += stat;
 881
 882                 oob += eccbytes;
 883
 884                 if (chip->ecc.postpad) {
 885                         chip->read_buf(mtd, oob, chip->ecc.postpad);
 886                         oob += chip->ecc.postpad;
 887                 }
 888         }
 889
 890         /* Calculate remaining oob bytes */
 891         i = mtd->oobsize - (oob - chip->oob_poi);
 892         if (i)
 893                 chip->read_buf(mtd, oob, i);
 894
 895         return 0;
 896 }
 897
 898 /**
 899  * nand_transfer_oob - [Internal] Transfer oob to client buffer
 900  * @chip:       nand chip structure
 901  * @oob:        oob destination address
 902  * @ops:        oob ops structure
 903  * @len:        size of oob to transfer
 904  */
 905 static uint8_t *nand_transfer_oob(struct nand_chip *chip, uint8_t *oob,
 906                                   struct mtd_oob_ops *ops, size_t len)
 907 {
 908         switch(ops->mode) {
 909
 910         case MTD_OOB_PLACE:
 911         case MTD_OOB_RAW:
 912                 memcpy(oob, chip->oob_poi + ops->ooboffs, len);
 913                 return oob + len;
 914
 915         case MTD_OOB_AUTO: {
 916                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
 917                 uint32_t boffs = 0, roffs = ops->ooboffs;
 918                 size_t bytes = 0;
 919
 920                 for(; free->length && len; free++, len -= bytes) {
 921                         /* Read request not from offset 0 ? */
 922                         if (unlikely(roffs)) {
 923                                 if (roffs >= free->length) {
 924                                         roffs -= free->length;
 925                                         continue;
 926                                 }
 927                                 boffs = free->offset + roffs;
 928                                 bytes = min_t(size_t, len,
 929                                               (free->length - roffs));
 930                                 roffs = 0;
 931                         } else {
 932                                 bytes = min_t(size_t, len, free->length);
 933                                 boffs = free->offset;
 934                         }
 935                         memcpy(oob, chip->oob_poi + boffs, bytes);
 936                         oob += bytes;
 937                 }
 938                 return oob;
 939         }
 940         default:
 941                 BUG();
 942         }
 943         return NULL;
 944 }
 945
 946 /**
 947  * nand_do_read_ops - [Internal] Read data with ECC
 948  *
 949  * @mtd:        MTD device structure
 950  * @from:       offset to read from
 951  * @ops:        oob ops structure
 952  *
 953  * Internal function. Called with chip held.
 954  */
 955 static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
 956                             struct mtd_oob_ops *ops)
 957 {
 958         int chipnr, page, realpage, col, bytes, aligned;
 959         struct nand_chip *chip = mtd->priv;
 960         struct mtd_ecc_stats stats;
 961         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
 962         int sndcmd = 1;
 963         int ret = 0;
 964         uint32_t readlen = ops->len;
 965         uint32_t oobreadlen = ops->ooblen;
 966         uint8_t *bufpoi, *oob, *buf;
 967
 968         stats = mtd->ecc_stats;
 969
 970         chipnr = (int)(from >> chip->chip_shift);
 971         chip->select_chip(mtd, chipnr);
 972
 973         realpage = (int)(from >> chip->page_shift);
 974         page = realpage & chip->pagemask;
 975
 976         col = (int)(from & (mtd->writesize - 1));
 977
 978         buf = ops->datbuf;
 979         oob = ops->oobbuf;
 980
 981         while(1) {
 982                 bytes = min(mtd->writesize - col, readlen);
 983                 aligned = (bytes == mtd->writesize);
 984
 985                 /* Is the current page in the buffer ? */
 986                 if (realpage != chip->pagebuf || oob) {
 987                         bufpoi = aligned ? buf : chip->buffers->databuf;
 988
 989                         if (likely(sndcmd)) {
 990                                 chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
 991                                 sndcmd = 0;
 992                         }
 993
 994                         /* Now read the page into the buffer */
 995                         if (unlikely(ops->mode == MTD_OOB_RAW))
 996                                 ret = chip->ecc.read_page_raw(mtd, chip, bufpoi);
 997                         else
 998                                 ret = chip->ecc.read_page(mtd, chip, bufpoi);
 999                         if (ret < 0)
1000                                 break;
1001
1002                         /* Transfer not aligned data */
1003                         if (!aligned) {
1004                                 chip->pagebuf = realpage;
1005                                 memcpy(buf, chip->buffers->databuf + col, bytes);
1006                         }
1007
1008                         buf += bytes;
1009
1010                         if (unlikely(oob)) {
1011                                 /* Raw mode does data:oob:data:oob */
1012                                 if (ops->mode != MTD_OOB_RAW) {
1013                                         int toread = min(oobreadlen,
1014                                                 chip->ecc.layout->oobavail);
1015                                         if (toread) {
1016                                                 oob = nand_transfer_oob(chip,
1017                                                         oob, ops, toread);
1018                                                 oobreadlen -= toread;
1019                                         }
1020                                 } else
1021                                         buf = nand_transfer_oob(chip,
1022                                                 buf, ops, mtd->oobsize);
1023                         }
1024
1025                         if (!(chip->options & NAND_NO_READRDY)) {
1026                                 /*
1027                                  * Apply delay or wait for ready/busy pin. Do
1028                                  * this before the AUTOINCR check, so no
1029                                  * problems arise if a chip which does auto
1030                                  * increment is marked as NOAUTOINCR by the
1031                                  * board driver.
1032                                  */
1033                                 if (!chip->dev_ready)
1034                                         udelay(chip->chip_delay);
1035                                 else
1036                                         nand_wait_ready(mtd);
1037                         }
1038                 } else {
1039                         memcpy(buf, chip->buffers->databuf + col, bytes);
1040                         buf += bytes;
1041                 }
1042
1043                 readlen -= bytes;
1044
1045                 if (!readlen)
1046                         break;
1047
1048                 /* For subsequent reads align to page boundary. */
1049                 col = 0;
1050                 /* Increment page address */
1051                 realpage++;
1052
1053                 page = realpage & chip->pagemask;
1054                 /* Check, if we cross a chip boundary */
1055                 if (!page) {
1056                         chipnr++;
1057                         chip->select_chip(mtd, -1);
1058                         chip->select_chip(mtd, chipnr);
1059                 }
1060
1061                 /* Check, if the chip supports auto page increment
1062                  * or if we have hit a block boundary.
1063                  */
1064                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1065                         sndcmd = 1;
1066         }
1067
1068         ops->retlen = ops->len - (size_t) readlen;
1069         if (oob)
1070                 ops->oobretlen = ops->ooblen - oobreadlen;
1071
1072         if (ret)
1073                 return ret;
1074
1075         if (mtd->ecc_stats.failed - stats.failed)
1076                 return -EBADMSG;
1077
1078         return  mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
1079 }
1080
1081 /**
1082  * nand_read - [MTD Interface] MTD compability function for nand_do_read_ecc
1083  * @mtd:        MTD device structure
1084  * @from:       offset to read from
1085  * @len:        number of bytes to read
1086  * @retlen:     pointer to variable to store the number of read bytes
1087  * @buf:        the databuffer to put data
1088  *
1089  * Get hold of the chip and call nand_do_read
1090  */
1091 static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
1092                      size_t *retlen, uint8_t *buf)
1093 {
1094         struct nand_chip *chip = mtd->priv;
1095         int ret;
1096
1097         /* Do not allow reads past end of device */
1098         if ((from + len) > mtd->size)
1099                 return -EINVAL;
1100         if (!len)
1101                 return 0;
1102
1103         nand_get_device(chip, mtd, FL_READING);
1104
1105         chip->ops.len = len;
1106         chip->ops.datbuf = buf;
1107         chip->ops.oobbuf = NULL;
1108
1109         ret = nand_do_read_ops(mtd, from, &chip->ops);
1110
1111         *retlen = chip->ops.retlen;
1112
1113         nand_release_device(mtd);
1114
1115         return ret;
1116 }
1117
1118 /**
1119  * nand_read_oob_std - [REPLACABLE] the most common OOB data read function
1120  * @mtd:        mtd info structure
1121  * @chip:       nand chip info structure
1122  * @page:       page number to read
1123  * @sndcmd:     flag whether to issue read command or not
1124  */
1125 static int nand_read_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1126                              int page, int sndcmd)
1127 {
1128         if (sndcmd) {
1129                 chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
1130                 sndcmd = 0;
1131         }
1132         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
1133         return sndcmd;
1134 }
1135
1136 /**
1137  * nand_read_oob_syndrome - [REPLACABLE] OOB data read function for HW ECC
1138  *                          with syndromes
1139  * @mtd:        mtd info structure
1140  * @chip:       nand chip info structure
1141  * @page:       page number to read
1142  * @sndcmd:     flag whether to issue read command or not
1143  */
1144 static int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
1145                                   int page, int sndcmd)
1146 {
1147         uint8_t *buf = chip->oob_poi;
1148         int length = mtd->oobsize;
1149         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1150         int eccsize = chip->ecc.size;
1151         uint8_t *bufpoi = buf;
1152         int i, toread, sndrnd = 0, pos;
1153
1154         chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
1155         for (i = 0; i < chip->ecc.steps; i++) {
1156                 if (sndrnd) {
1157                         pos = eccsize + i * (eccsize + chunk);
1158                         if (mtd->writesize > 512)
1159                                 chip->cmdfunc(mtd, NAND_CMD_RNDOUT, pos, -1);
1160                         else
1161                                 chip->cmdfunc(mtd, NAND_CMD_READ0, pos, page);
1162                 } else
1163                         sndrnd = 1;
1164                 toread = min_t(int, length, chunk);
1165                 chip->read_buf(mtd, bufpoi, toread);
1166                 bufpoi += toread;
1167                 length -= toread;
1168         }
1169         if (length > 0)
1170                 chip->read_buf(mtd, bufpoi, length);
1171
1172         return 1;
1173 }
1174
1175 /**
1176  * nand_write_oob_std - [REPLACABLE] the most common OOB data write function
1177  * @mtd:        mtd info structure
1178  * @chip:       nand chip info structure
1179  * @page:       page number to write
1180  */
1181 static int nand_write_oob_std(struct mtd_info *mtd, struct nand_chip *chip,
1182                               int page)
1183 {
1184         int status = 0;
1185         const uint8_t *buf = chip->oob_poi;
1186         int length = mtd->oobsize;
1187
1188         chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
1189         chip->write_buf(mtd, buf, length);
1190         /* Send command to program the OOB data */
1191         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1192
1193         status = chip->waitfunc(mtd, chip);
1194
1195         return status & NAND_STATUS_FAIL ? -EIO : 0;
1196 }
1197
1198 /**
1199  * nand_write_oob_syndrome - [REPLACABLE] OOB data write function for HW ECC
1200  *                           with syndrome - only for large page flash !
1201  * @mtd:        mtd info structure
1202  * @chip:       nand chip info structure
1203  * @page:       page number to write
1204  */
1205 static int nand_write_oob_syndrome(struct mtd_info *mtd,
1206                                    struct nand_chip *chip, int page)
1207 {
1208         int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
1209         int eccsize = chip->ecc.size, length = mtd->oobsize;
1210         int i, len, pos, status = 0, sndcmd = 0, steps = chip->ecc.steps;
1211         const uint8_t *bufpoi = chip->oob_poi;
1212
1213         /*
1214          * data-ecc-data-ecc ... ecc-oob
1215          * or
1216          * data-pad-ecc-pad-data-pad .... ecc-pad-oob
1217          */
1218         if (!chip->ecc.prepad && !chip->ecc.postpad) {
1219                 pos = steps * (eccsize + chunk);
1220                 steps = 0;
1221         } else
1222                 pos = eccsize;
1223
1224         chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
1225         for (i = 0; i < steps; i++) {
1226                 if (sndcmd) {
1227                         if (mtd->writesize <= 512) {
1228                                 uint32_t fill = 0xFFFFFFFF;
1229
1230                                 len = eccsize;
1231                                 while (len > 0) {
1232                                         int num = min_t(int, len, 4);
1233                                         chip->write_buf(mtd, (uint8_t *)&fill,
1234                                                         num);
1235                                         len -= num;
1236                                 }
1237                         } else {
1238                                 pos = eccsize + i * (eccsize + chunk);
1239                                 chip->cmdfunc(mtd, NAND_CMD_RNDIN, pos, -1);
1240                         }
1241                 } else
1242                         sndcmd = 1;
1243                 len = min_t(int, length, chunk);
1244                 chip->write_buf(mtd, bufpoi, len);
1245                 bufpoi += len;
1246                 length -= len;
1247         }
1248         if (length > 0)
1249                 chip->write_buf(mtd, bufpoi, length);
1250
1251         chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1252         status = chip->waitfunc(mtd, chip);
1253
1254         return status & NAND_STATUS_FAIL ? -EIO : 0;
1255 }
1256
1257 /**
1258  * nand_do_read_oob - [Intern] NAND read out-of-band
1259  * @mtd:        MTD device structure
1260  * @from:       offset to read from
1261  * @ops:        oob operations description structure
1262  *
1263  * NAND read out-of-band data from the spare area
1264  */
1265 static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
1266                             struct mtd_oob_ops *ops)
1267 {
1268         int page, realpage, chipnr, sndcmd = 1;
1269         struct nand_chip *chip = mtd->priv;
1270         int blkcheck = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1271         int readlen = ops->ooblen;
1272         int len;
1273         uint8_t *buf = ops->oobbuf;
1274
1275         DEBUG(MTD_DEBUG_LEVEL3, "nand_read_oob: from = 0x%08Lx, len = %i\n",
1276               (unsigned long long)from, readlen);
1277
1278         if (ops->mode == MTD_OOB_AUTO)
1279                 len = chip->ecc.layout->oobavail;
1280         else
1281                 len = mtd->oobsize;
1282
1283         if (unlikely(ops->ooboffs >= len)) {
1284                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1285                         "Attempt to start read outside oob\n");
1286                 return -EINVAL;
1287         }
1288
1289         /* Do not allow reads past end of device */
1290         if (unlikely(from >= mtd->size ||
1291                      ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
1292                                         (from >> chip->page_shift)) * len)) {
1293                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1294                         "Attempt read beyond end of device\n");
1295                 return -EINVAL;
1296         }
1297
1298         chipnr = (int)(from >> chip->chip_shift);
1299         chip->select_chip(mtd, chipnr);
1300
1301         /* Shift to get page */
1302         realpage = (int)(from >> chip->page_shift);
1303         page = realpage & chip->pagemask;
1304
1305         while(1) {
1306                 sndcmd = chip->ecc.read_oob(mtd, chip, page, sndcmd);
1307
1308                 len = min(len, readlen);
1309                 buf = nand_transfer_oob(chip, buf, ops, len);
1310
1311                 if (!(chip->options & NAND_NO_READRDY)) {
1312                         /*
1313                          * Apply delay or wait for ready/busy pin. Do this
1314                          * before the AUTOINCR check, so no problems arise if a
1315                          * chip which does auto increment is marked as
1316                          * NOAUTOINCR by the board driver.
1317                          */
1318                         if (!chip->dev_ready)
1319                                 udelay(chip->chip_delay);
1320                         else
1321                                 nand_wait_ready(mtd);
1322                 }
1323
1324                 readlen -= len;
1325                 if (!readlen)
1326                         break;
1327
1328                 /* Increment page address */
1329                 realpage++;
1330
1331                 page = realpage & chip->pagemask;
1332                 /* Check, if we cross a chip boundary */
1333                 if (!page) {
1334                         chipnr++;
1335                         chip->select_chip(mtd, -1);
1336                         chip->select_chip(mtd, chipnr);
1337                 }
1338
1339                 /* Check, if the chip supports auto page increment
1340                  * or if we have hit a block boundary.
1341                  */
1342                 if (!NAND_CANAUTOINCR(chip) || !(page & blkcheck))
1343                         sndcmd = 1;
1344         }
1345
1346         ops->oobretlen = ops->ooblen;
1347         return 0;
1348 }
1349
1350 /**
1351  * nand_read_oob - [MTD Interface] NAND read data and/or out-of-band
1352  * @mtd:        MTD device structure
1353  * @from:       offset to read from
1354  * @ops:        oob operation description structure
1355  *
1356  * NAND read data and/or out-of-band data
1357  */
1358 static int nand_read_oob(struct mtd_info *mtd, loff_t from,
1359                          struct mtd_oob_ops *ops)
1360 {
1361         struct nand_chip *chip = mtd->priv;
1362         int ret = -ENOTSUPP;
1363
1364         ops->retlen = 0;
1365
1366         /* Do not allow reads past end of device */
1367         if (ops->datbuf && (from + ops->len) > mtd->size) {
1368                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1369                       "Attempt read beyond end of device\n");
1370                 return -EINVAL;
1371         }
1372
1373         nand_get_device(chip, mtd, FL_READING);
1374
1375         switch(ops->mode) {
1376         case MTD_OOB_PLACE:
1377         case MTD_OOB_AUTO:
1378         case MTD_OOB_RAW:
1379                 break;
1380
1381         default:
1382                 goto out;
1383         }
1384
1385         if (!ops->datbuf)
1386                 ret = nand_do_read_oob(mtd, from, ops);
1387         else
1388                 ret = nand_do_read_ops(mtd, from, ops);
1389
1390  out:
1391         nand_release_device(mtd);
1392         return ret;
1393 }
1394
1395
1396 /**
1397  * nand_write_page_raw - [Intern] raw page write function
1398  * @mtd:        mtd info structure
1399  * @chip:       nand chip info structure
1400  * @buf:        data buffer
1401  */
1402 static void nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1403                                 const uint8_t *buf)
1404 {
1405         chip->write_buf(mtd, buf, mtd->writesize);
1406         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1407 }
1408
1409 /**
1410  * nand_write_page_swecc - [REPLACABLE] software ecc based page write function
1411  * @mtd:        mtd info structure
1412  * @chip:       nand chip info structure
1413  * @buf:        data buffer
1414  */
1415 static void nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
1416                                   const uint8_t *buf)
1417 {
1418         int i, eccsize = chip->ecc.size;
1419         int eccbytes = chip->ecc.bytes;
1420         int eccsteps = chip->ecc.steps;
1421         uint8_t *ecc_calc = chip->buffers->ecccalc;
1422         const uint8_t *p = buf;
1423         uint32_t *eccpos = chip->ecc.layout->eccpos;
1424
1425         /* Software ecc calculation */
1426         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
1427                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1428
1429         for (i = 0; i < chip->ecc.total; i++)
1430                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1431
1432         chip->ecc.write_page_raw(mtd, chip, buf);
1433 }
1434
1435 /**
1436  * nand_write_page_hwecc - [REPLACABLE] hardware ecc based page write function
1437  * @mtd:        mtd info structure
1438  * @chip:       nand chip info structure
1439  * @buf:        data buffer
1440  */
1441 static void nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
1442                                   const uint8_t *buf)
1443 {
1444         int i, eccsize = chip->ecc.size;
1445         int eccbytes = chip->ecc.bytes;
1446         int eccsteps = chip->ecc.steps;
1447         uint8_t *ecc_calc = chip->buffers->ecccalc;
1448         const uint8_t *p = buf;
1449         uint32_t *eccpos = chip->ecc.layout->eccpos;
1450
1451         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1452                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1453                 chip->write_buf(mtd, p, eccsize);
1454                 chip->ecc.calculate(mtd, p, &ecc_calc[i]);
1455         }
1456
1457         for (i = 0; i < chip->ecc.total; i++)
1458                 chip->oob_poi[eccpos[i]] = ecc_calc[i];
1459
1460         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
1461 }
1462
1463 /**
1464  * nand_write_page_syndrome - [REPLACABLE] hardware ecc syndrom based page write
1465  * @mtd:        mtd info structure
1466  * @chip:       nand chip info structure
1467  * @buf:        data buffer
1468  *
1469  * The hw generator calculates the error syndrome automatically. Therefor
1470  * we need a special oob layout and handling.
1471  */
1472 static void nand_write_page_syndrome(struct mtd_info *mtd,
1473                                     struct nand_chip *chip, const uint8_t *buf)
1474 {
1475         int i, eccsize = chip->ecc.size;
1476         int eccbytes = chip->ecc.bytes;
1477         int eccsteps = chip->ecc.steps;
1478         const uint8_t *p = buf;
1479         uint8_t *oob = chip->oob_poi;
1480
1481         for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
1482
1483                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
1484                 chip->write_buf(mtd, p, eccsize);
1485
1486                 if (chip->ecc.prepad) {
1487                         chip->write_buf(mtd, oob, chip->ecc.prepad);
1488                         oob += chip->ecc.prepad;
1489                 }
1490
1491                 chip->ecc.calculate(mtd, p, oob);
1492                 chip->write_buf(mtd, oob, eccbytes);
1493                 oob += eccbytes;
1494
1495                 if (chip->ecc.postpad) {
1496                         chip->write_buf(mtd, oob, chip->ecc.postpad);
1497                         oob += chip->ecc.postpad;
1498                 }
1499         }
1500
1501         /* Calculate remaining oob bytes */
1502         i = mtd->oobsize - (oob - chip->oob_poi);
1503         if (i)
1504                 chip->write_buf(mtd, oob, i);
1505 }
1506
1507 /**
1508  * nand_write_page - [REPLACEABLE] write one page
1509  * @mtd:        MTD device structure
1510  * @chip:       NAND chip descriptor
1511  * @buf:        the data to write
1512  * @page:       page number to write
1513  * @cached:     cached programming
1514  * @raw:        use _raw version of write_page
1515  */
1516 static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
1517                            const uint8_t *buf, int page, int cached, int raw)
1518 {
1519         int status;
1520
1521         chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
1522
1523         if (unlikely(raw))
1524                 chip->ecc.write_page_raw(mtd, chip, buf);
1525         else
1526                 chip->ecc.write_page(mtd, chip, buf);
1527
1528         /*
1529          * Cached progamming disabled for now, Not sure if its worth the
1530          * trouble. The speed gain is not very impressive. (2.3->2.6Mib/s)
1531          */
1532         cached = 0;
1533
1534         if (!cached || !(chip->options & NAND_CACHEPRG)) {
1535
1536                 chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
1537                 status = chip->waitfunc(mtd, chip);
1538                 /*
1539                  * See if operation failed and additional status checks are
1540                  * available
1541                  */
1542                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
1543                         status = chip->errstat(mtd, chip, FL_WRITING, status,
1544                                                page);
1545
1546                 if (status & NAND_STATUS_FAIL)
1547                         return -EIO;
1548         } else {
1549                 chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
1550                 status = chip->waitfunc(mtd, chip);
1551         }
1552
1553 #ifdef CONFIG_MTD_NAND_VERIFY_WRITE
1554         /* Send command to read back the data */
1555         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
1556
1557         if (chip->verify_buf(mtd, buf, mtd->writesize))
1558                 return -EIO;
1559 #endif
1560         return 0;
1561 }
1562
1563 /**
1564  * nand_fill_oob - [Internal] Transfer client buffer to oob
1565  * @chip:       nand chip structure
1566  * @oob:        oob data buffer
1567  * @ops:        oob ops structure
1568  */
1569 static uint8_t *nand_fill_oob(struct nand_chip *chip, uint8_t *oob,
1570                                   struct mtd_oob_ops *ops)
1571 {
1572         size_t len = ops->ooblen;
1573
1574         switch(ops->mode) {
1575
1576         case MTD_OOB_PLACE:
1577         case MTD_OOB_RAW:
1578                 memcpy(chip->oob_poi + ops->ooboffs, oob, len);
1579                 return oob + len;
1580
1581         case MTD_OOB_AUTO: {
1582                 struct nand_oobfree *free = chip->ecc.layout->oobfree;
1583                 uint32_t boffs = 0, woffs = ops->ooboffs;
1584                 size_t bytes = 0;
1585
1586                 for(; free->length && len; free++, len -= bytes) {
1587                         /* Write request not from offset 0 ? */
1588                         if (unlikely(woffs)) {
1589                                 if (woffs >= free->length) {
1590                                         woffs -= free->length;
1591                                         continue;
1592                                 }
1593                                 boffs = free->offset + woffs;
1594                                 bytes = min_t(size_t, len,
1595                                               (free->length - woffs));
1596                                 woffs = 0;
1597                         } else {
1598                                 bytes = min_t(size_t, len, free->length);
1599                                 boffs = free->offset;
1600                         }
1601                         memcpy(chip->oob_poi + boffs, oob, bytes);
1602                         oob += bytes;
1603                 }
1604                 return oob;
1605         }
1606         default:
1607                 BUG();
1608         }
1609         return NULL;
1610 }
1611
1612 #define NOTALIGNED(x)   (x & (chip->subpagesize - 1)) != 0
1613
1614 /**
1615  * nand_do_write_ops - [Internal] NAND write with ECC
1616  * @mtd:        MTD device structure
1617  * @to:         offset to write to
1618  * @ops:        oob operations description structure
1619  *
1620  * NAND write with ECC
1621  */
1622 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
1623                              struct mtd_oob_ops *ops)
1624 {
1625         int chipnr, realpage, page, blockmask, column;
1626         struct nand_chip *chip = mtd->priv;
1627         uint32_t writelen = ops->len;
1628         uint8_t *oob = ops->oobbuf;
1629         uint8_t *buf = ops->datbuf;
1630         int ret, subpage;
1631
1632         ops->retlen = 0;
1633         if (!writelen)
1634                 return 0;
1635
1636         /* reject writes, which are not page aligned */
1637         if (NOTALIGNED(to) || NOTALIGNED(ops->len)) {
1638                 printk(KERN_NOTICE "nand_write: "
1639                        "Attempt to write not page aligned data\n");
1640                 return -EINVAL;
1641         }
1642
1643         column = to & (mtd->writesize - 1);
1644         subpage = column || (writelen & (mtd->writesize - 1));
1645
1646         if (subpage && oob)
1647                 return -EINVAL;
1648
1649         chipnr = (int)(to >> chip->chip_shift);
1650         chip->select_chip(mtd, chipnr);
1651
1652         /* Check, if it is write protected */
1653         if (nand_check_wp(mtd))
1654                 return -EIO;
1655
1656         realpage = (int)(to >> chip->page_shift);
1657         page = realpage & chip->pagemask;
1658         blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
1659
1660         /* Invalidate the page cache, when we write to the cached page */
1661         if (to <= (chip->pagebuf << chip->page_shift) &&
1662             (chip->pagebuf << chip->page_shift) < (to + ops->len))
1663                 chip->pagebuf = -1;
1664
1665         /* If we're not given explicit OOB data, let it be 0xFF */
1666         if (likely(!oob))
1667                 memset(chip->oob_poi, 0xff, mtd->oobsize);
1668
1669         while(1) {
1670                 int bytes = mtd->writesize;
1671                 int cached = writelen > bytes && page != blockmask;
1672                 uint8_t *wbuf = buf;
1673
1674                 /* Partial page write ? */
1675                 if (unlikely(column || writelen < (mtd->writesize - 1))) {
1676                         cached = 0;
1677                         bytes = min_t(int, bytes - column, (int) writelen);
1678                         chip->pagebuf = -1;
1679                         memset(chip->buffers->databuf, 0xff, mtd->writesize);
1680                         memcpy(&chip->buffers->databuf[column], buf, bytes);
1681                         wbuf = chip->buffers->databuf;
1682                 }
1683
1684                 if (unlikely(oob))
1685                         oob = nand_fill_oob(chip, oob, ops);
1686
1687                 ret = chip->write_page(mtd, chip, wbuf, page, cached,
1688                                        (ops->mode == MTD_OOB_RAW));
1689                 if (ret)
1690                         break;
1691
1692                 writelen -= bytes;
1693                 if (!writelen)
1694                         break;
1695
1696                 column = 0;
1697                 buf += bytes;
1698                 realpage++;
1699
1700                 page = realpage & chip->pagemask;
1701                 /* Check, if we cross a chip boundary */
1702                 if (!page) {
1703                         chipnr++;
1704                         chip->select_chip(mtd, -1);
1705                         chip->select_chip(mtd, chipnr);
1706                 }
1707         }
1708
1709         ops->retlen = ops->len - writelen;
1710         if (unlikely(oob))
1711                 ops->oobretlen = ops->ooblen;
1712         return ret;
1713 }
1714
1715 /**
1716  * nand_write - [MTD Interface] NAND write with ECC
1717  * @mtd:        MTD device structure
1718  * @to:         offset to write to
1719  * @len:        number of bytes to write
1720  * @retlen:     pointer to variable to store the number of written bytes
1721  * @buf:        the data to write
1722  *
1723  * NAND write with ECC
1724  */
1725 static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
1726                           size_t *retlen, const uint8_t *buf)
1727 {
1728         struct nand_chip *chip = mtd->priv;
1729         int ret;
1730
1731         /* Do not allow reads past end of device */
1732         if ((to + len) > mtd->size)
1733                 return -EINVAL;
1734         if (!len)
1735                 return 0;
1736
1737         nand_get_device(chip, mtd, FL_WRITING);
1738
1739         chip->ops.len = len;
1740         chip->ops.datbuf = (uint8_t *)buf;
1741         chip->ops.oobbuf = NULL;
1742
1743         ret = nand_do_write_ops(mtd, to, &chip->ops);
1744
1745         *retlen = chip->ops.retlen;
1746
1747         nand_release_device(mtd);
1748
1749         return ret;
1750 }
1751
1752 /**
1753  * nand_do_write_oob - [MTD Interface] NAND write out-of-band
1754  * @mtd:        MTD device structure
1755  * @to:         offset to write to
1756  * @ops:        oob operation description structure
1757  *
1758  * NAND write out-of-band
1759  */
1760 static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
1761                              struct mtd_oob_ops *ops)
1762 {
1763         int chipnr, page, status, len;
1764         struct nand_chip *chip = mtd->priv;
1765
1766         DEBUG(MTD_DEBUG_LEVEL3, "nand_write_oob: to = 0x%08x, len = %i\n",
1767               (unsigned int)to, (int)ops->ooblen);
1768
1769         if (ops->mode == MTD_OOB_AUTO)
1770                 len = chip->ecc.layout->oobavail;
1771         else
1772                 len = mtd->oobsize;
1773
1774         /* Do not allow write past end of page */
1775         if ((ops->ooboffs + ops->ooblen) > len) {
1776                 DEBUG(MTD_DEBUG_LEVEL0, "nand_write_oob: "
1777                       "Attempt to write past end of page\n");
1778                 return -EINVAL;
1779         }
1780
1781         if (unlikely(ops->ooboffs >= len)) {
1782                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1783                         "Attempt to start write outside oob\n");
1784                 return -EINVAL;
1785         }
1786
1787         /* Do not allow reads past end of device */
1788         if (unlikely(to >= mtd->size ||
1789                      ops->ooboffs + ops->ooblen >
1790                         ((mtd->size >> chip->page_shift) -
1791                          (to >> chip->page_shift)) * len)) {
1792                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1793                         "Attempt write beyond end of device\n");
1794                 return -EINVAL;
1795         }
1796
1797         chipnr = (int)(to >> chip->chip_shift);
1798         chip->select_chip(mtd, chipnr);
1799
1800         /* Shift to get page */
1801         page = (int)(to >> chip->page_shift);
1802
1803         /*
1804          * Reset the chip. Some chips (like the Toshiba TC5832DC found in one
1805          * of my DiskOnChip 2000 test units) will clear the whole data page too
1806          * if we don't do this. I have no clue why, but I seem to have 'fixed'
1807          * it in the doc2000 driver in August 1999.  dwmw2.
1808          */
1809         chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
1810
1811         /* Check, if it is write protected */
1812         if (nand_check_wp(mtd))
1813                 return -EROFS;
1814
1815         /* Invalidate the page cache, if we write to the cached page */
1816         if (page == chip->pagebuf)
1817                 chip->pagebuf = -1;
1818
1819         memset(chip->oob_poi, 0xff, mtd->oobsize);
1820         nand_fill_oob(chip, ops->oobbuf, ops);
1821         status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
1822         memset(chip->oob_poi, 0xff, mtd->oobsize);
1823
1824         if (status)
1825                 return status;
1826
1827         ops->oobretlen = ops->ooblen;
1828
1829         return 0;
1830 }
1831
1832 /**
1833  * nand_write_oob - [MTD Interface] NAND write data and/or out-of-band
1834  * @mtd:        MTD device structure
1835  * @to:         offset to write to
1836  * @ops:        oob operation description structure
1837  */
1838 static int nand_write_oob(struct mtd_info *mtd, loff_t to,
1839                           struct mtd_oob_ops *ops)
1840 {
1841         struct nand_chip *chip = mtd->priv;
1842         int ret = -ENOTSUPP;
1843
1844         ops->retlen = 0;
1845
1846         /* Do not allow writes past end of device */
1847         if (ops->datbuf && (to + ops->len) > mtd->size) {
1848                 DEBUG(MTD_DEBUG_LEVEL0, "nand_read_oob: "
1849                       "Attempt read beyond end of device\n");
1850                 return -EINVAL;
1851         }
1852
1853         nand_get_device(chip, mtd, FL_WRITING);
1854
1855         switch(ops->mode) {
1856         case MTD_OOB_PLACE:
1857         case MTD_OOB_AUTO:
1858         case MTD_OOB_RAW:
1859                 break;
1860
1861         default:
1862                 goto out;
1863         }
1864
1865         if (!ops->datbuf)
1866                 ret = nand_do_write_oob(mtd, to, ops);
1867         else
1868                 ret = nand_do_write_ops(mtd, to, ops);
1869
1870  out:
1871         nand_release_device(mtd);
1872         return ret;
1873 }
1874
1875 /**
1876  * single_erease_cmd - [GENERIC] NAND standard block erase command function
1877  * @mtd:        MTD device structure
1878  * @page:       the page address of the block which will be erased
1879  *
1880  * Standard erase command for NAND chips
1881  */
1882 static void single_erase_cmd(struct mtd_info *mtd, int page)
1883 {
1884         struct nand_chip *chip = mtd->priv;
1885         /* Send commands to erase a block */
1886         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
1887         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
1888 }
1889
1890 /**
1891  * multi_erease_cmd - [GENERIC] AND specific block erase command function
1892  * @mtd:        MTD device structure
1893  * @page:       the page address of the block which will be erased
1894  *
1895  * AND multi block erase command function
1896  * Erase 4 consecutive blocks
1897  */
1898 static void multi_erase_cmd(struct mtd_info *mtd, int page)
1899 {
1900         struct nand_chip *chip = mtd->priv;
1901         /* Send commands to erase a block */
1902         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1903         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1904         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page++);
1905         chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
1906         chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
1907 }
1908
1909 /**
1910  * nand_erase - [MTD Interface] erase block(s)
1911  * @mtd:        MTD device structure
1912  * @instr:      erase instruction
1913  *
1914  * Erase one ore more blocks
1915  */
1916 static int nand_erase(struct mtd_info *mtd, struct erase_info *instr)
1917 {
1918         return nand_erase_nand(mtd, instr, 0);
1919 }
1920
1921 #define BBT_PAGE_MASK   0xffffff3f
1922 /**
1923  * nand_erase_nand - [Internal] erase block(s)
1924  * @mtd:        MTD device structure
1925  * @instr:      erase instruction
1926  * @allowbbt:   allow erasing the bbt area
1927  *
1928  * Erase one ore more blocks
1929  */
1930 int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
1931                     int allowbbt)
1932 {
1933         int page, len, status, pages_per_block, ret, chipnr;
1934         struct nand_chip *chip = mtd->priv;
1935         int rewrite_bbt[NAND_MAX_CHIPS]={0};
1936         unsigned int bbt_masked_page = 0xffffffff;
1937
1938         DEBUG(MTD_DEBUG_LEVEL3, "nand_erase: start = 0x%08x, len = %i\n",
1939               (unsigned int)instr->addr, (unsigned int)instr->len);
1940
1941         /* Start address must align on block boundary */
1942         if (instr->addr & ((1 << chip->phys_erase_shift) - 1)) {
1943                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: Unaligned address\n");
1944                 return -EINVAL;
1945         }
1946
1947         /* Length must align on block boundary */
1948         if (instr->len & ((1 << chip->phys_erase_shift) - 1)) {
1949                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
1950                       "Length not block aligned\n");
1951                 return -EINVAL;
1952         }
1953
1954         /* Do not allow erase past end of device */
1955         if ((instr->len + instr->addr) > mtd->size) {
1956                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
1957                       "Erase past end of device\n");
1958                 return -EINVAL;
1959         }
1960
1961         instr->fail_addr = 0xffffffff;
1962
1963         /* Grab the lock and see if the device is available */
1964         nand_get_device(chip, mtd, FL_ERASING);
1965
1966         /* Shift to get first page */
1967         page = (int)(instr->addr >> chip->page_shift);
1968         chipnr = (int)(instr->addr >> chip->chip_shift);
1969
1970         /* Calculate pages in each block */
1971         pages_per_block = 1 << (chip->phys_erase_shift - chip->page_shift);
1972
1973         /* Select the NAND device */
1974         chip->select_chip(mtd, chipnr);
1975
1976         /* Check, if it is write protected */
1977         if (nand_check_wp(mtd)) {
1978                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
1979                       "Device is write protected!!!\n");
1980                 instr->state = MTD_ERASE_FAILED;
1981                 goto erase_exit;
1982         }
1983
1984         /*
1985          * If BBT requires refresh, set the BBT page mask to see if the BBT
1986          * should be rewritten. Otherwise the mask is set to 0xffffffff which
1987          * can not be matched. This is also done when the bbt is actually
1988          * erased to avoid recusrsive updates
1989          */
1990         if (chip->options & BBT_AUTO_REFRESH && !allowbbt)
1991                 bbt_masked_page = chip->bbt_td->pages[chipnr] & BBT_PAGE_MASK;
1992
1993         /* Loop through the pages */
1994         len = instr->len;
1995
1996         instr->state = MTD_ERASING;
1997
1998         while (len) {
1999                 /*
2000                  * heck if we have a bad block, we do not erase bad blocks !
2001                  */
2002                 if (nand_block_checkbad(mtd, ((loff_t) page) <<
2003                                         chip->page_shift, 0, allowbbt)) {
2004                         printk(KERN_WARNING "nand_erase: attempt to erase a "
2005                                "bad block at page 0x%08x\n", page);
2006                         instr->state = MTD_ERASE_FAILED;
2007                         goto erase_exit;
2008                 }
2009
2010                 /*
2011                  * Invalidate the page cache, if we erase the block which
2012                  * contains the current cached page
2013                  */
2014                 if (page <= chip->pagebuf && chip->pagebuf <
2015                     (page + pages_per_block))
2016                         chip->pagebuf = -1;
2017
2018                 chip->erase_cmd(mtd, page & chip->pagemask);
2019
2020                 status = chip->waitfunc(mtd, chip);
2021
2022                 /*
2023                  * See if operation failed and additional status checks are
2024                  * available
2025                  */
2026                 if ((status & NAND_STATUS_FAIL) && (chip->errstat))
2027                         status = chip->errstat(mtd, chip, FL_ERASING,
2028                                                status, page);
2029
2030                 /* See if block erase succeeded */
2031                 if (status & NAND_STATUS_FAIL) {
2032                         DEBUG(MTD_DEBUG_LEVEL0, "nand_erase: "
2033                               "Failed erase, page 0x%08x\n", page);
2034                         instr->state = MTD_ERASE_FAILED;
2035                         instr->fail_addr = (page << chip->page_shift);
2036                         goto erase_exit;
2037                 }
2038
2039                 /*
2040                  * If BBT requires refresh, set the BBT rewrite flag to the
2041                  * page being erased
2042                  */
2043                 if (bbt_masked_page != 0xffffffff &&
2044                     (page & BBT_PAGE_MASK) == bbt_masked_page)
2045                             rewrite_bbt[chipnr] = (page << chip->page_shift);
2046
2047                 /* Increment page address and decrement length */
2048                 len -= (1 << chip->phys_erase_shift);
2049                 page += pages_per_block;
2050
2051                 /* Check, if we cross a chip boundary */
2052                 if (len && !(page & chip->pagemask)) {
2053                         chipnr++;
2054                         chip->select_chip(mtd, -1);
2055                         chip->select_chip(mtd, chipnr);
2056
2057                         /*
2058                          * If BBT requires refresh and BBT-PERCHIP, set the BBT
2059                          * page mask to see if this BBT should be rewritten
2060                          */
2061                         if (bbt_masked_page != 0xffffffff &&
2062                             (chip->bbt_td->options & NAND_BBT_PERCHIP))
2063                                 bbt_masked_page = chip->bbt_td->pages[chipnr] &
2064                                         BBT_PAGE_MASK;
2065                 }
2066         }
2067         instr->state = MTD_ERASE_DONE;
2068
2069  erase_exit:
2070
2071         ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
2072
2073         /* Deselect and wake up anyone waiting on the device */
2074         nand_release_device(mtd);
2075
2076         /* Do call back function */
2077         if (!ret)
2078                 mtd_erase_callback(instr);
2079
2080         /*
2081          * If BBT requires refresh and erase was successful, rewrite any
2082          * selected bad block tables
2083          */
2084         if (bbt_masked_page == 0xffffffff || ret)
2085                 return ret;
2086
2087         for (chipnr = 0; chipnr < chip->numchips; chipnr++) {
2088                 if (!rewrite_bbt[chipnr])
2089                         continue;
2090                 /* update the BBT for chip */
2091                 DEBUG(MTD_DEBUG_LEVEL0, "nand_erase_nand: nand_update_bbt "
2092                       "(%d:0x%0x 0x%0x)\n", chipnr, rewrite_bbt[chipnr],
2093                       chip->bbt_td->pages[chipnr]);
2094                 nand_update_bbt(mtd, rewrite_bbt[chipnr]);
2095         }
2096
2097         /* Return more or less happy */
2098         return ret;
2099 }
2100
2101 /**
2102  * nand_sync - [MTD Interface] sync
2103  * @mtd:        MTD device structure
2104  *
2105  * Sync is actually a wait for chip ready function
2106  */
2107 static void nand_sync(struct mtd_info *mtd)
2108 {
2109         struct nand_chip *chip = mtd->priv;
2110
2111         DEBUG(MTD_DEBUG_LEVEL3, "nand_sync: called\n");
2112
2113         /* Grab the lock and see if the device is available */
2114         nand_get_device(chip, mtd, FL_SYNCING);
2115         /* Release it and go back */
2116         nand_release_device(mtd);
2117 }
2118
2119 /**
2120  * nand_block_isbad - [MTD Interface] Check if block at offset is bad
2121  * @mtd:        MTD device structure
2122  * @offs:       offset relative to mtd start
2123  */
2124 static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
2125 {
2126         /* Check for invalid offset */
2127         if (offs > mtd->size)
2128                 return -EINVAL;
2129
2130         return nand_block_checkbad(mtd, offs, 1, 0);
2131 }
2132
2133 /**
2134  * nand_block_markbad - [MTD Interface] Mark block at the given offset as bad
2135  * @mtd:        MTD device structure
2136  * @ofs:        offset relative to mtd start
2137  */
2138 static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
2139 {
2140         struct nand_chip *chip = mtd->priv;
2141         int ret;
2142
2143         if ((ret = nand_block_isbad(mtd, ofs))) {
2144                 /* If it was bad already, return success and do nothing. */
2145                 if (ret > 0)
2146                         return 0;
2147                 return ret;
2148         }
2149
2150         return chip->block_markbad(mtd, ofs);
2151 }
2152
2153 /**
2154  * nand_suspend - [MTD Interface] Suspend the NAND flash
2155  * @mtd:        MTD device structure
2156  */
2157 static int nand_suspend(struct mtd_info *mtd)
2158 {
2159         struct nand_chip *chip = mtd->priv;
2160
2161         return nand_get_device(chip, mtd, FL_PM_SUSPENDED);
2162 }
2163
2164 /**
2165  * nand_resume - [MTD Interface] Resume the NAND flash
2166  * @mtd:        MTD device structure
2167  */
2168 static void nand_resume(struct mtd_info *mtd)
2169 {
2170         struct nand_chip *chip = mtd->priv;
2171
2172         if (chip->state == FL_PM_SUSPENDED)
2173                 nand_release_device(mtd);
2174         else
2175                 printk(KERN_ERR "nand_resume() called for a chip which is not "
2176                        "in suspended state\n");
2177 }
2178
2179 /*
2180  * Set default functions
2181  */
2182 static void nand_set_defaults(struct nand_chip *chip, int busw)
2183 {
2184         /* check for proper chip_delay setup, set 20us if not */
2185         if (!chip->chip_delay)
2186                 chip->chip_delay = 20;
2187
2188         /* check, if a user supplied command function given */
2189         if (chip->cmdfunc == NULL)
2190                 chip->cmdfunc = nand_command;
2191
2192         /* check, if a user supplied wait function given */
2193         if (chip->waitfunc == NULL)
2194                 chip->waitfunc = nand_wait;
2195
2196         if (!chip->select_chip)
2197                 chip->select_chip = nand_select_chip;
2198         if (!chip->read_byte)
2199                 chip->read_byte = busw ? nand_read_byte16 : nand_read_byte;
2200         if (!chip->read_word)
2201                 chip->read_word = nand_read_word;
2202         if (!chip->block_bad)
2203                 chip->block_bad = nand_block_bad;
2204         if (!chip->block_markbad)
2205                 chip->block_markbad = nand_default_block_markbad;
2206         if (!chip->write_buf)
2207                 chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
2208         if (!chip->read_buf)
2209                 chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
2210         if (!chip->verify_buf)
2211                 chip->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf;
2212         if (!chip->scan_bbt)
2213                 chip->scan_bbt = nand_default_bbt;
2214
2215         if (!chip->controller) {
2216                 chip->controller = &chip->hwcontrol;
2217                 spin_lock_init(&chip->controller->lock);
2218                 init_waitqueue_head(&chip->controller->wq);
2219         }
2220
2221 }
2222
2223 /*
2224  * Get the flash and manufacturer id and lookup if the type is supported
2225  */
2226 static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
2227                                                   struct nand_chip *chip,
2228                                                   int busw, int *maf_id)
2229 {
2230         struct nand_flash_dev *type = NULL;
2231         int i, dev_id, maf_idx;
2232
2233         /* Select the device */
2234         chip->select_chip(mtd, 0);
2235
2236         /* Send the command for reading device ID */
2237         chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2238
2239         /* Read manufacturer and device IDs */
2240         *maf_id = chip->read_byte(mtd);
2241         dev_id = chip->read_byte(mtd);
2242
2243         /* Lookup the flash id */
2244         for (i = 0; nand_flash_ids[i].name != NULL; i++) {
2245                 if (dev_id == nand_flash_ids[i].id) {
2246                         type =  &nand_flash_ids[i];
2247                         break;
2248                 }
2249         }
2250
2251         if (!type)
2252                 return ERR_PTR(-ENODEV);
2253
2254         if (!mtd->name)
2255                 mtd->name = type->name;
2256
2257         chip->chipsize = type->chipsize << 20;
2258
2259         /* Newer devices have all the information in additional id bytes */
2260         if (!type->pagesize) {
2261                 int extid;
2262                 /* The 3rd id byte holds MLC / multichip data */
2263                 chip->cellinfo = chip->read_byte(mtd);
2264                 /* The 4th id byte is the important one */
2265                 extid = chip->read_byte(mtd);
2266                 /* Calc pagesize */
2267                 mtd->writesize = 1024 << (extid & 0x3);
2268                 extid >>= 2;
2269                 /* Calc oobsize */
2270                 mtd->oobsize = (8 << (extid & 0x01)) * (mtd->writesize >> 9);
2271                 extid >>= 2;
2272                 /* Calc blocksize. Blocksize is multiples of 64KiB */
2273                 mtd->erasesize = (64 * 1024) << (extid & 0x03);
2274                 extid >>= 2;
2275                 /* Get buswidth information */
2276                 busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
2277
2278         } else {
2279                 /*
2280                  * Old devices have chip data hardcoded in the device id table
2281                  */
2282                 mtd->erasesize = type->erasesize;
2283                 mtd->writesize = type->pagesize;
2284                 mtd->oobsize = mtd->writesize / 32;
2285                 busw = type->options & NAND_BUSWIDTH_16;
2286         }
2287
2288         /* Try to identify manufacturer */
2289         for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_idx++) {
2290                 if (nand_manuf_ids[maf_idx].id == *maf_id)
2291                         break;
2292         }
2293
2294         /*
2295          * Check, if buswidth is correct. Hardware drivers should set
2296          * chip correct !
2297          */
2298         if (busw != (chip->options & NAND_BUSWIDTH_16)) {
2299                 printk(KERN_INFO "NAND device: Manufacturer ID:"
2300                        " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id,
2301                        dev_id, nand_manuf_ids[maf_idx].name, mtd->name);
2302                 printk(KERN_WARNING "NAND bus width %d instead %d bit\n",
2303                        (chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
2304                        busw ? 16 : 8);
2305                 return ERR_PTR(-EINVAL);
2306         }
2307
2308         /* Calculate the address shift from the page size */
2309         chip->page_shift = ffs(mtd->writesize) - 1;
2310         /* Convert chipsize to number of pages per chip -1. */
2311         chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
2312
2313         chip->bbt_erase_shift = chip->phys_erase_shift =
2314                 ffs(mtd->erasesize) - 1;
2315         chip->chip_shift = ffs(chip->chipsize) - 1;
2316
2317         /* Set the bad block position */
2318         chip->badblockpos = mtd->writesize > 512 ?
2319                 NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS;
2320
2321         /* Get chip options, preserve non chip based options */
2322         chip->options &= ~NAND_CHIPOPTIONS_MSK;
2323         chip->options |= type->options & NAND_CHIPOPTIONS_MSK;
2324
2325         /*
2326          * Set chip as a default. Board drivers can override it, if necessary
2327          */
2328         chip->options |= NAND_NO_AUTOINCR;
2329
2330         /* Check if chip is a not a samsung device. Do not clear the
2331          * options for chips which are not having an extended id.
2332          */
2333         if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
2334                 chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
2335
2336         /* Check for AND chips with 4 page planes */
2337         if (chip->options & NAND_4PAGE_ARRAY)
2338                 chip->erase_cmd = multi_erase_cmd;
2339         else
2340                 chip->erase_cmd = single_erase_cmd;
2341
2342         /* Do not replace user supplied command function ! */
2343         if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
2344                 chip->cmdfunc = nand_command_lp;
2345
2346         printk(KERN_INFO "NAND device: Manufacturer ID:"
2347                " 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id, dev_id,
2348                nand_manuf_ids[maf_idx].name, type->name);
2349
2350         return type;
2351 }
2352
2353 /**
2354  * nand_scan_ident - [NAND Interface] Scan for the NAND device
2355  * @mtd:             MTD device structure
2356  * @maxchips:        Number of chips to scan for
2357  *
2358  * This is the first phase of the normal nand_scan() function. It
2359  * reads the flash ID and sets up MTD fields accordingly.
2360  *
2361  * The mtd->owner field must be set to the module of the caller.
2362  */
2363 int nand_scan_ident(struct mtd_info *mtd, int maxchips)
2364 {
2365         int i, busw, nand_maf_id;
2366         struct nand_chip *chip = mtd->priv;
2367         struct nand_flash_dev *type;
2368
2369         /* Get buswidth to select the correct functions */
2370         busw = chip->options & NAND_BUSWIDTH_16;
2371         /* Set the default functions */
2372         nand_set_defaults(chip, busw);
2373
2374         /* Read the flash type */
2375         type = nand_get_flash_type(mtd, chip, busw, &nand_maf_id);
2376
2377         if (IS_ERR(type)) {
2378                 printk(KERN_WARNING "No NAND device found!!!\n");
2379                 chip->select_chip(mtd, -1);
2380                 return PTR_ERR(type);
2381         }
2382
2383         /* Check for a chip array */
2384         for (i = 1; i < maxchips; i++) {
2385                 chip->select_chip(mtd, i);
2386                 /* Send the command for reading device ID */
2387                 chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
2388                 /* Read manufacturer and device IDs */
2389                 if (nand_maf_id != chip->read_byte(mtd) ||
2390                     type->id != chip->read_byte(mtd))
2391                         break;
2392         }
2393         if (i > 1)
2394                 printk(KERN_INFO "%d NAND chips detected\n", i);
2395
2396         /* Store the number of chips and calc total size for mtd */
2397         chip->numchips = i;
2398         mtd->size = i * chip->chipsize;
2399
2400         return 0;
2401 }
2402
2403
2404 /**
2405  * nand_scan_tail - [NAND Interface] Scan for the NAND device
2406  * @mtd:            MTD device structure
2407  * @maxchips:       Number of chips to scan for
2408  *
2409  * This is the second phase of the normal nand_scan() function. It
2410  * fills out all the uninitialized function pointers with the defaults
2411  * and scans for a bad block table if appropriate.
2412  */
2413 int nand_scan_tail(struct mtd_info *mtd)
2414 {
2415         int i;
2416         struct nand_chip *chip = mtd->priv;
2417
2418         if (!(chip->options & NAND_OWN_BUFFERS))
2419                 chip->buffers = kmalloc(sizeof(*chip->buffers), GFP_KERNEL);
2420         if (!chip->buffers)
2421                 return -ENOMEM;
2422
2423         /* Set the internal oob buffer location, just after the page data */
2424         chip->oob_poi = chip->buffers->databuf + mtd->writesize;
2425
2426         /*
2427          * If no default placement scheme is given, select an appropriate one
2428          */
2429         if (!chip->ecc.layout) {
2430                 switch (mtd->oobsize) {
2431                 case 8:
2432                         chip->ecc.layout = &nand_oob_8;
2433                         break;
2434                 case 16:
2435                         chip->ecc.layout = &nand_oob_16;
2436                         break;
2437                 case 64:
2438                         chip->ecc.layout = &nand_oob_64;
2439                         break;
2440                 default:
2441                         printk(KERN_WARNING "No oob scheme defined for "
2442                                "oobsize %d\n", mtd->oobsize);
2443                         BUG();
2444                 }
2445         }
2446
2447         if (!chip->write_page)
2448                 chip->write_page = nand_write_page;
2449
2450         /*
2451          * check ECC mode, default to software if 3byte/512byte hardware ECC is
2452          * selected and we have 256 byte pagesize fallback to software ECC
2453          */
2454         if (!chip->ecc.read_page_raw)
2455                 chip->ecc.read_page_raw = nand_read_page_raw;
2456         if (!chip->ecc.write_page_raw)
2457                 chip->ecc.write_page_raw = nand_write_page_raw;
2458
2459         switch (chip->ecc.mode) {
2460         case NAND_ECC_HW:
2461                 /* Use standard hwecc read page function ? */
2462                 if (!chip->ecc.read_page)
2463                         chip->ecc.read_page = nand_read_page_hwecc;
2464                 if (!chip->ecc.write_page)
2465                         chip->ecc.write_page = nand_write_page_hwecc;
2466                 if (!chip->ecc.read_oob)
2467                         chip->ecc.read_oob = nand_read_oob_std;
2468                 if (!chip->ecc.write_oob)
2469                         chip->ecc.write_oob = nand_write_oob_std;
2470
2471         case NAND_ECC_HW_SYNDROME:
2472                 if (!chip->ecc.calculate || !chip->ecc.correct ||
2473                     !chip->ecc.hwctl) {
2474                         printk(KERN_WARNING "No ECC functions supplied, "
2475                                "Hardware ECC not possible\n");
2476                         BUG();
2477                 }
2478                 /* Use standard syndrome read/write page function ? */
2479                 if (!chip->ecc.read_page)
2480                         chip->ecc.read_page = nand_read_page_syndrome;
2481                 if (!chip->ecc.write_page)
2482                         chip->ecc.write_page = nand_write_page_syndrome;
2483                 if (!chip->ecc.read_oob)
2484                         chip->ecc.read_oob = nand_read_oob_syndrome;
2485                 if (!chip->ecc.write_oob)
2486                         chip->ecc.write_oob = nand_write_oob_syndrome;
2487
2488                 if (mtd->writesize >= chip->ecc.size)
2489                         break;
2490                 printk(KERN_WARNING "%d byte HW ECC not possible on "
2491                        "%d byte page size, fallback to SW ECC\n",
2492                        chip->ecc.size, mtd->writesize);
2493                 chip->ecc.mode = NAND_ECC_SOFT;
2494
2495         case NAND_ECC_SOFT:
2496                 chip->ecc.calculate = nand_calculate_ecc;
2497                 chip->ecc.correct = nand_correct_data;
2498                 chip->ecc.read_page = nand_read_page_swecc;
2499                 chip->ecc.write_page = nand_write_page_swecc;
2500                 chip->ecc.read_oob = nand_read_oob_std;
2501                 chip->ecc.write_oob = nand_write_oob_std;
2502                 chip->ecc.size = 256;
2503                 chip->ecc.bytes = 3;
2504                 break;
2505
2506         case NAND_ECC_NONE:
2507                 printk(KERN_WARNING "NAND_ECC_NONE selected by board driver. "
2508                        "This is not recommended !!\n");
2509                 chip->ecc.read_page = nand_read_page_raw;
2510                 chip->ecc.write_page = nand_write_page_raw;
2511                 chip->ecc.read_oob = nand_read_oob_std;
2512                 chip->ecc.write_oob = nand_write_oob_std;
2513                 chip->ecc.size = mtd->writesize;
2514                 chip->ecc.bytes = 0;
2515                 break;
2516
2517         default:
2518                 printk(KERN_WARNING "Invalid NAND_ECC_MODE %d\n",
2519                        chip->ecc.mode);
2520                 BUG();
2521         }
2522
2523         /*
2524          * The number of bytes available for a client to place data into
2525          * the out of band area
2526          */
2527         chip->ecc.layout->oobavail = 0;
2528         for (i = 0; chip->ecc.layout->oobfree[i].length; i++)
2529                 chip->ecc.layout->oobavail +=
2530                         chip->ecc.layout->oobfree[i].length;
2531         mtd->oobavail = chip->ecc.layout->oobavail;
2532
2533         /*
2534          * Set the number of read / write steps for one page depending on ECC
2535          * mode
2536          */
2537         chip->ecc.steps = mtd->writesize / chip->ecc.size;
2538         if(chip->ecc.steps * chip->ecc.size != mtd->writesize) {
2539                 printk(KERN_WARNING "Invalid ecc parameters\n");
2540                 BUG();
2541         }
2542         chip->ecc.total = chip->ecc.steps * chip->ecc.bytes;
2543
2544         /*
2545          * Allow subpage writes up to ecc.steps. Not possible for MLC
2546          * FLASH.
2547          */
2548         if (!(chip->options & NAND_NO_SUBPAGE_WRITE) &&
2549             !(chip->cellinfo & NAND_CI_CELLTYPE_MSK)) {
2550                 switch(chip->ecc.steps) {
2551                 case 2:
2552                         mtd->subpage_sft = 1;
2553                         break;
2554                 case 4:
2555                 case 8:
2556                         mtd->subpage_sft = 2;
2557                         break;
2558                 }
2559         }
2560         chip->subpagesize = mtd->writesize >> mtd->subpage_sft;
2561
2562         /* Initialize state */
2563         chip->state = FL_READY;
2564
2565         /* De-select the device */
2566         chip->select_chip(mtd, -1);
2567
2568         /* Invalidate the pagebuffer reference */
2569         chip->pagebuf = -1;
2570
2571         /* Fill in remaining MTD driver data */
2572         mtd->type = MTD_NANDFLASH;
2573         mtd->flags = MTD_CAP_NANDFLASH;
2574         mtd->erase = nand_erase;
2575         mtd->point = NULL;
2576         mtd->unpoint = NULL;
2577         mtd->read = nand_read;
2578         mtd->write = nand_write;
2579         mtd->read_oob = nand_read_oob;
2580         mtd->write_oob = nand_write_oob;
2581         mtd->sync = nand_sync;
2582         mtd->lock = NULL;
2583         mtd->unlock = NULL;
2584         mtd->suspend = nand_suspend;
2585         mtd->resume = nand_resume;
2586         mtd->block_isbad = nand_block_isbad;
2587         mtd->block_markbad = nand_block_markbad;
2588
2589         /* propagate ecc.layout to mtd_info */
2590         mtd->ecclayout = chip->ecc.layout;
2591
2592         /* Check, if we should skip the bad block table scan */
2593         if (chip->options & NAND_SKIP_BBTSCAN)
2594                 return 0;
2595
2596         /* Build bad block table */
2597         return chip->scan_bbt(mtd);
2598 }
2599
2600 /* module_text_address() isn't exported, and it's mostly a pointless
2601    test if this is a module _anyway_ -- they'd have to try _really_ hard
2602    to call us from in-kernel code if the core NAND support is modular. */
2603 #ifdef MODULE
2604 #define caller_is_module() (1)
2605 #else
2606 #define caller_is_module() \
2607         module_text_address((unsigned long)__builtin_return_address(0))
2608 #endif
2609
2610 /**
2611  * nand_scan - [NAND Interface] Scan for the NAND device
2612  * @mtd:        MTD device structure
2613  * @maxchips:   Number of chips to scan for
2614  *
2615  * This fills out all the uninitialized function pointers
2616  * with the defaults.
2617  * The flash ID is read and the mtd/chip structures are
2618  * filled with the appropriate values.
2619  * The mtd->owner field must be set to the module of the caller
2620  *
2621  */
2622 int nand_scan(struct mtd_info *mtd, int maxchips)
2623 {
2624         int ret;
2625
2626         /* Many callers got this wrong, so check for it for a while... */
2627         if (!mtd->owner && caller_is_module()) {
2628                 printk(KERN_CRIT "nand_scan() called with NULL mtd->owner!\n");
2629                 BUG();
2630         }
2631
2632         ret = nand_scan_ident(mtd, maxchips);
2633         if (!ret)
2634                 ret = nand_scan_tail(mtd);
2635         return ret;
2636 }
2637
2638 /**
2639  * nand_release - [NAND Interface] Free resources held by the NAND device
2640  * @mtd:        MTD device structure
2641 */
2642 void nand_release(struct mtd_info *mtd)
2643 {
2644         struct nand_chip *chip = mtd->priv;
2645
2646 #ifdef CONFIG_MTD_PARTITIONS
2647         /* Deregister partitions */
2648         del_mtd_partitions(mtd);
2649 #endif
2650         /* Deregister the device */
2651         del_mtd_device(mtd);
2652
2653         /* Free bad block table memory */
2654         kfree(chip->bbt);
2655         if (!(chip->options & NAND_OWN_BUFFERS))
2656                 kfree(chip->buffers);
2657 }
2658
2659 EXPORT_SYMBOL_GPL(nand_scan);
2660 EXPORT_SYMBOL_GPL(nand_scan_ident);
2661 EXPORT_SYMBOL_GPL(nand_scan_tail);
2662 EXPORT_SYMBOL_GPL(nand_release);
2663
2664 static int __init nand_base_init(void)
2665 {
2666         led_trigger_register_simple("nand-disk", &nand_led_trigger);
2667         return 0;
2668 }
2669
2670 static void __exit nand_base_exit(void)
2671 {
2672         led_trigger_unregister_simple(nand_led_trigger);
2673 }
2674
2675 module_init(nand_base_init);
2676 module_exit(nand_base_exit);
2677
2678 MODULE_LICENSE("GPL");
2679 MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>, Thomas Gleixner <tglx@linutronix.de>");
2680 MODULE_DESCRIPTION("Generic NAND flash driver code");