drivers/mtd : move mtd drivers to drivers/mtd

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

1 files changed, 0 insertions, 1052 deletions

diff --git a/drivers/nand/nand_bbt.c b/drivers/nand/nand_bbt.c
deleted file mode 100644
index 19a9bc2..0000000
--- a/drivers/nand/nand_bbt.c
+++ /dev/null
@@ -1,1052 +0,0 @@
-/*
- *  drivers/mtd/nand_bbt.c
- *
- *  Overview:
- *   Bad block table support for the NAND driver
- *
- *  Copyright (C) 2004 Thomas Gleixner (tglx@linutronix.de)
- *
- * $Id: nand_bbt.c,v 1.28 2004/11/13 10:19:09 gleixner Exp $
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * Description:
- *
- * When nand_scan_bbt is called, then it tries to find the bad block table
- * depending on the options in the bbt descriptor(s). If a bbt is found
- * then the contents are read and the memory based bbt is created. If a
- * mirrored bbt is selected then the mirror is searched too and the
- * versions are compared. If the mirror has a greater version number
- * than the mirror bbt is used to build the memory based bbt.
- * If the tables are not versioned, then we "or" the bad block information.
- * If one of the bbt's is out of date or does not exist it is (re)created.
- * If no bbt exists at all then the device is scanned for factory marked
- * good / bad blocks and the bad block tables are created.
- *
- * For manufacturer created bbts like the one found on M-SYS DOC devices
- * the bbt is searched and read but never created
- *
- * The autogenerated bad block table is located in the last good blocks
- * of the device. The table is mirrored, so it can be updated eventually.
- * The table is marked in the oob area with an ident pattern and a version
- * number which indicates which of both tables is more up to date.
- *
- * The table uses 2 bits per block
- * 11b: 	block is good
- * 00b: 	block is factory marked bad
- * 01b, 10b: 	block is marked bad due to wear
- *
- * The memory bad block table uses the following scheme:
- * 00b:		block is good
- * 01b:		block is marked bad due to wear
- * 10b:		block is reserved (to protect the bbt area)
- * 11b:		block is factory marked bad
- *
- * Multichip devices like DOC store the bad block info per floor.
- *
- * Following assumptions are made:
- * - bbts start at a page boundary, if autolocated on a block boundary
- * - the space neccecary for a bbt in FLASH does not exceed a block boundary
- *
- */
-
-#include <common.h>
-
-#if defined(CONFIG_CMD_NAND) && !defined(CFG_NAND_LEGACY)
-
-#include <malloc.h>
-#include <linux/mtd/compat.h>
-#include <linux/mtd/mtd.h>
-#include <linux/mtd/nand.h>
-
-#include <asm/errno.h>
-
-/**
- * check_pattern - [GENERIC] check if a pattern is in the buffer
- * @buf:	the buffer to search
- * @len:	the length of buffer to search
- * @paglen:	the pagelength
- * @td:		search pattern descriptor
- *
- * Check for a pattern at the given place. Used to search bad block
- * tables and good / bad block identifiers.
- * If the SCAN_EMPTY option is set then check, if all bytes except the
- * pattern area contain 0xff
- *
-*/
-static int check_pattern (uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td)
-{
-	int i, end;
-	uint8_t *p = buf;
-
-	end = paglen + td->offs;
-	if (td->options & NAND_BBT_SCANEMPTY) {
-		for (i = 0; i < end; i++) {
-			if (p[i] != 0xff)
-				return -1;
-		}
-	}
-	p += end;
-
-	/* Compare the pattern */
-	for (i = 0; i < td->len; i++) {
-		if (p[i] != td->pattern[i])
-			return -1;
-	}
-
-	p += td->len;
-	end += td->len;
-	if (td->options & NAND_BBT_SCANEMPTY) {
-		for (i = end; i < len; i++) {
-			if (*p++ != 0xff)
-				return -1;
-		}
-	}
-	return 0;
-}
-
-/**
- * read_bbt - [GENERIC] Read the bad block table starting from page
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @page:	the starting page
- * @num:	the number of bbt descriptors to read
- * @bits:	number of bits per block
- * @offs:	offset in the memory table
- * @reserved_block_code:	Pattern to identify reserved blocks
- *
- * Read the bad block table starting from page.
- *
- */
-static int read_bbt (struct mtd_info *mtd, uint8_t *buf, int page, int num,
-	int bits, int offs, int reserved_block_code)
-{
-	int res, i, j, act = 0;
-	struct nand_chip *this = mtd->priv;
-	size_t retlen, len, totlen;
-	loff_t from;
-	uint8_t msk = (uint8_t) ((1 << bits) - 1);
-
-	totlen = (num * bits) >> 3;
-	from = ((loff_t)page) << this->page_shift;
-
-	while (totlen) {
-		len = min (totlen, (size_t) (1 << this->bbt_erase_shift));
-		res = mtd->read_ecc (mtd, from, len, &retlen, buf, NULL, this->autooob);
-		if (res < 0) {
-			if (retlen != len) {
-				printk (KERN_INFO "nand_bbt: Error reading bad block table\n");
-				return res;
-			}
-			printk (KERN_WARNING "nand_bbt: ECC error while reading bad block table\n");
-		}
-
-		/* Analyse data */
-		for (i = 0; i < len; i++) {
-			uint8_t dat = buf[i];
-			for (j = 0; j < 8; j += bits, act += 2) {
-				uint8_t tmp = (dat >> j) & msk;
-				if (tmp == msk)
-					continue;
-				if (reserved_block_code &&
-				    (tmp == reserved_block_code)) {
-					printk (KERN_DEBUG "nand_read_bbt: Reserved block at 0x%08x\n",
-						((offs << 2) + (act >> 1)) << this->bbt_erase_shift);
-					this->bbt[offs + (act >> 3)] |= 0x2 << (act & 0x06);
-					continue;
-				}
-				/* Leave it for now, if its matured we can move this
-				 * message to MTD_DEBUG_LEVEL0 */
-				printk (KERN_DEBUG "nand_read_bbt: Bad block at 0x%08x\n",
-					((offs << 2) + (act >> 1)) << this->bbt_erase_shift);
-				/* Factory marked bad or worn out ? */
-				if (tmp == 0)
-					this->bbt[offs + (act >> 3)] |= 0x3 << (act & 0x06);
-				else
-					this->bbt[offs + (act >> 3)] |= 0x1 << (act & 0x06);
-			}
-		}
-		totlen -= len;
-		from += len;
-	}
-	return 0;
-}
-
-/**
- * read_abs_bbt - [GENERIC] Read the bad block table starting at a given page
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @td:		descriptor for the bad block table
- * @chip:	read the table for a specific chip, -1 read all chips.
- *		Applies only if NAND_BBT_PERCHIP option is set
- *
- * Read the bad block table for all chips starting at a given page
- * We assume that the bbt bits are in consecutive order.
-*/
-static int read_abs_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *td, int chip)
-{
-	struct nand_chip *this = mtd->priv;
-	int res = 0, i;
-	int bits;
-
-	bits = td->options & NAND_BBT_NRBITS_MSK;
-	if (td->options & NAND_BBT_PERCHIP) {
-		int offs = 0;
-		for (i = 0; i < this->numchips; i++) {
-			if (chip == -1 || chip == i)
-				res = read_bbt (mtd, buf, td->pages[i], this->chipsize >> this->bbt_erase_shift, bits, offs, td->reserved_block_code);
-			if (res)
-				return res;
-			offs += this->chipsize >> (this->bbt_erase_shift + 2);
-		}
-	} else {
-		res = read_bbt (mtd, buf, td->pages[0], mtd->size >> this->bbt_erase_shift, bits, 0, td->reserved_block_code);
-		if (res)
-			return res;
-	}
-	return 0;
-}
-
-/**
- * read_abs_bbts - [GENERIC] Read the bad block table(s) for all chips starting at a given page
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @td:		descriptor for the bad block table
- * @md:		descriptor for the bad block table mirror
- *
- * Read the bad block table(s) for all chips starting at a given page
- * We assume that the bbt bits are in consecutive order.
- *
-*/
-static int read_abs_bbts (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *td,
-	struct nand_bbt_descr *md)
-{
-	struct nand_chip *this = mtd->priv;
-
-	/* Read the primary version, if available */
-	if (td->options & NAND_BBT_VERSION) {
-		nand_read_raw (mtd, buf, td->pages[0] << this->page_shift, mtd->oobblock, mtd->oobsize);
-		td->version[0] = buf[mtd->oobblock + td->veroffs];
-		printk (KERN_DEBUG "Bad block table at page %d, version 0x%02X\n", td->pages[0], td->version[0]);
-	}
-
-	/* Read the mirror version, if available */
-	if (md && (md->options & NAND_BBT_VERSION)) {
-		nand_read_raw (mtd, buf, md->pages[0] << this->page_shift, mtd->oobblock, mtd->oobsize);
-		md->version[0] = buf[mtd->oobblock + md->veroffs];
-		printk (KERN_DEBUG "Bad block table at page %d, version 0x%02X\n", md->pages[0], md->version[0]);
-	}
-
-	return 1;
-}
-
-/**
- * create_bbt - [GENERIC] Create a bad block table by scanning the device
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @bd:		descriptor for the good/bad block search pattern
- * @chip:	create the table for a specific chip, -1 read all chips.
- *		Applies only if NAND_BBT_PERCHIP option is set
- *
- * Create a bad block table by scanning the device
- * for the given good/bad block identify pattern
- */
-static void create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *bd, int chip)
-{
-	struct nand_chip *this = mtd->priv;
-	int i, j, numblocks, len, scanlen;
-	int startblock;
-	loff_t from;
-	size_t readlen, ooblen;
-
-	if (bd->options & NAND_BBT_SCANALLPAGES)
-		len = 1 << (this->bbt_erase_shift - this->page_shift);
-	else {
-		if (bd->options & NAND_BBT_SCAN2NDPAGE)
-			len = 2;
-		else
-			len = 1;
-	}
-	scanlen	= mtd->oobblock + mtd->oobsize;
-	readlen = len * mtd->oobblock;
-	ooblen = len * mtd->oobsize;
-
-	if (chip == -1) {
-		/* Note that numblocks is 2 * (real numblocks) here, see i+=2 below as it
-		 * makes shifting and masking less painful */
-		numblocks = mtd->size >> (this->bbt_erase_shift - 1);
-		startblock = 0;
-		from = 0;
-	} else {
-		if (chip >= this->numchips) {
-			printk (KERN_WARNING "create_bbt(): chipnr (%d) > available chips (%d)\n",
-				chip + 1, this->numchips);
-			return;
-		}
-		numblocks = this->chipsize >> (this->bbt_erase_shift - 1);
-		startblock = chip * numblocks;
-		numblocks += startblock;
-		from = startblock << (this->bbt_erase_shift - 1);
-	}
-
-	for (i = startblock; i < numblocks;) {
-		nand_read_raw (mtd, buf, from, readlen, ooblen);
-		for (j = 0; j < len; j++) {
-			if (check_pattern (&buf[j * scanlen], scanlen, mtd->oobblock, bd)) {
-				this->bbt[i >> 3] |= 0x03 << (i & 0x6);
-				break;
-			}
-		}
-		i += 2;
-		from += (1 << this->bbt_erase_shift);
-	}
-}
-
-/**
- * search_bbt - [GENERIC] scan the device for a specific bad block table
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @td:		descriptor for the bad block table
- *
- * Read the bad block table by searching for a given ident pattern.
- * Search is preformed either from the beginning up or from the end of
- * the device downwards. The search starts always at the start of a
- * block.
- * If the option NAND_BBT_PERCHIP is given, each chip is searched
- * for a bbt, which contains the bad block information of this chip.
- * This is neccecary to provide support for certain DOC devices.
- *
- * The bbt ident pattern resides in the oob area of the first page
- * in a block.
- */
-static int search_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *td)
-{
-	struct nand_chip *this = mtd->priv;
-	int i, chips;
-	int bits, startblock, block, dir;
-	int scanlen = mtd->oobblock + mtd->oobsize;
-	int bbtblocks;
-
-	/* Search direction top -> down ? */
-	if (td->options & NAND_BBT_LASTBLOCK) {
-		startblock = (mtd->size >> this->bbt_erase_shift) -1;
-		dir = -1;
-	} else {
-		startblock = 0;
-		dir = 1;
-	}
-
-	/* Do we have a bbt per chip ? */
-	if (td->options & NAND_BBT_PERCHIP) {
-		chips = this->numchips;
-		bbtblocks = this->chipsize >> this->bbt_erase_shift;
-		startblock &= bbtblocks - 1;
-	} else {
-		chips = 1;
-		bbtblocks = mtd->size >> this->bbt_erase_shift;
-	}
-
-	/* Number of bits for each erase block in the bbt */
-	bits = td->options & NAND_BBT_NRBITS_MSK;
-
-	for (i = 0; i < chips; i++) {
-		/* Reset version information */
-		td->version[i] = 0;
-		td->pages[i] = -1;
-		/* Scan the maximum number of blocks */
-		for (block = 0; block < td->maxblocks; block++) {
-			int actblock = startblock + dir * block;
-			/* Read first page */
-			nand_read_raw (mtd, buf, actblock << this->bbt_erase_shift, mtd->oobblock, mtd->oobsize);
-			if (!check_pattern(buf, scanlen, mtd->oobblock, td)) {
-				td->pages[i] = actblock << (this->bbt_erase_shift - this->page_shift);
-				if (td->options & NAND_BBT_VERSION) {
-					td->version[i] = buf[mtd->oobblock + td->veroffs];
-				}
-				break;
-			}
-		}
-		startblock += this->chipsize >> this->bbt_erase_shift;
-	}
-	/* Check, if we found a bbt for each requested chip */
-	for (i = 0; i < chips; i++) {
-		if (td->pages[i] == -1)
-			printk (KERN_WARNING "Bad block table not found for chip %d\n", i);
-		else
-			printk (KERN_DEBUG "Bad block table found at page %d, version 0x%02X\n", td->pages[i], td->version[i]);
-	}
-	return 0;
-}
-
-/**
- * search_read_bbts - [GENERIC] scan the device for bad block table(s)
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @td:		descriptor for the bad block table
- * @md:		descriptor for the bad block table mirror
- *
- * Search and read the bad block table(s)
-*/
-static int search_read_bbts (struct mtd_info *mtd, uint8_t *buf,
-	struct nand_bbt_descr *td, struct nand_bbt_descr *md)
-{
-	/* Search the primary table */
-	search_bbt (mtd, buf, td);
-
-	/* Search the mirror table */
-	if (md)
-		search_bbt (mtd, buf, md);
-
-	/* Force result check */
-	return 1;
-}
-
-
-/**
- * write_bbt - [GENERIC] (Re)write the bad block table
- *
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @td:		descriptor for the bad block table
- * @md:		descriptor for the bad block table mirror
- * @chipsel:	selector for a specific chip, -1 for all
- *
- * (Re)write the bad block table
- *
-*/
-static int write_bbt (struct mtd_info *mtd, uint8_t *buf,
-	struct nand_bbt_descr *td, struct nand_bbt_descr *md, int chipsel)
-{
-	struct nand_chip *this = mtd->priv;
-	struct nand_oobinfo oobinfo;
-	struct erase_info einfo;
-	int i, j, res, chip = 0;
-	int bits, startblock, dir, page, offs, numblocks, sft, sftmsk;
-	int nrchips, bbtoffs, pageoffs;
-	uint8_t msk[4];
-	uint8_t rcode = td->reserved_block_code;
-	size_t retlen, len = 0;
-	loff_t to;
-
-	if (!rcode)
-		rcode = 0xff;
-	/* Write bad block table per chip rather than per device ? */
-	if (td->options & NAND_BBT_PERCHIP) {
-		numblocks = (int) (this->chipsize >> this->bbt_erase_shift);
-		/* Full device write or specific chip ? */
-		if (chipsel == -1) {
-			nrchips = this->numchips;
-		} else {
-			nrchips = chipsel + 1;
-			chip = chipsel;
-		}
-	} else {
-		numblocks = (int) (mtd->size >> this->bbt_erase_shift);
-		nrchips = 1;
-	}
-
-	/* Loop through the chips */
-	for (; chip < nrchips; chip++) {
-
-		/* There was already a version of the table, reuse the page
-		 * This applies for absolute placement too, as we have the
-		 * page nr. in td->pages.
-		 */
-		if (td->pages[chip] != -1) {
-			page = td->pages[chip];
-			goto write;
-		}
-
-		/* Automatic placement of the bad block table */
-		/* Search direction top -> down ? */
-		if (td->options & NAND_BBT_LASTBLOCK) {
-			startblock = numblocks * (chip + 1) - 1;
-			dir = -1;
-		} else {
-			startblock = chip * numblocks;
-			dir = 1;
-		}
-
-		for (i = 0; i < td->maxblocks; i++) {
-			int block = startblock + dir * i;
-			/* Check, if the block is bad */
-			switch ((this->bbt[block >> 2] >> (2 * (block & 0x03))) & 0x03) {
-			case 0x01:
-			case 0x03:
-				continue;
-			}
-			page = block << (this->bbt_erase_shift - this->page_shift);
-			/* Check, if the block is used by the mirror table */
-			if (!md || md->pages[chip] != page)
-				goto write;
-		}
-		printk (KERN_ERR "No space left to write bad block table\n");
-		return -ENOSPC;
-write:
-
-		/* Set up shift count and masks for the flash table */
-		bits = td->options & NAND_BBT_NRBITS_MSK;
-		switch (bits) {
-		case 1: sft = 3; sftmsk = 0x07; msk[0] = 0x00; msk[1] = 0x01; msk[2] = ~rcode; msk[3] = 0x01; break;
-		case 2: sft = 2; sftmsk = 0x06; msk[0] = 0x00; msk[1] = 0x01; msk[2] = ~rcode; msk[3] = 0x03; break;
-		case 4: sft = 1; sftmsk = 0x04; msk[0] = 0x00; msk[1] = 0x0C; msk[2] = ~rcode; msk[3] = 0x0f; break;
-		case 8: sft = 0; sftmsk = 0x00; msk[0] = 0x00; msk[1] = 0x0F; msk[2] = ~rcode; msk[3] = 0xff; break;
-		default: return -EINVAL;
-		}
-
-		bbtoffs = chip * (numblocks >> 2);
-
-		to = ((loff_t) page) << this->page_shift;
-
-		memcpy (&oobinfo, this->autooob, sizeof(oobinfo));
-		oobinfo.useecc = MTD_NANDECC_PLACEONLY;
-
-		/* Must we save the block contents ? */
-		if (td->options & NAND_BBT_SAVECONTENT) {
-			/* Make it block aligned */
-			to &= ~((loff_t) ((1 << this->bbt_erase_shift) - 1));
-			len = 1 << this->bbt_erase_shift;
-			res = mtd->read_ecc (mtd, to, len, &retlen, buf, &buf[len], &oobinfo);
-			if (res < 0) {
-				if (retlen != len) {
-					printk (KERN_INFO "nand_bbt: Error reading block for writing the bad block table\n");
-					return res;
-				}
-				printk (KERN_WARNING "nand_bbt: ECC error while reading block for writing bad block table\n");
-			}
-			/* Calc the byte offset in the buffer */
-			pageoffs = page - (int)(to >> this->page_shift);
-			offs = pageoffs << this->page_shift;
-			/* Preset the bbt area with 0xff */
-			memset (&buf[offs], 0xff, (size_t)(numblocks >> sft));
-			/* Preset the bbt's oob area with 0xff */
-			memset (&buf[len + pageoffs * mtd->oobsize], 0xff,
-				((len >> this->page_shift) - pageoffs) * mtd->oobsize);
-			if (td->options & NAND_BBT_VERSION) {
-				buf[len + (pageoffs * mtd->oobsize) + td->veroffs] = td->version[chip];
-			}
-		} else {
-			/* Calc length */
-			len = (size_t) (numblocks >> sft);
-			/* Make it page aligned ! */
-			len = (len + (mtd->oobblock-1)) & ~(mtd->oobblock-1);
-			/* Preset the buffer with 0xff */
-			memset (buf, 0xff, len + (len >> this->page_shift) * mtd->oobsize);
-			offs = 0;
-			/* Pattern is located in oob area of first page */
-			memcpy (&buf[len + td->offs], td->pattern, td->len);
-			if (td->options & NAND_BBT_VERSION) {
-				buf[len + td->veroffs] = td->version[chip];
-			}
-		}
-
-		/* walk through the memory table */
-		for (i = 0; i < numblocks; ) {
-			uint8_t dat;
-			dat = this->bbt[bbtoffs + (i >> 2)];
-			for (j = 0; j < 4; j++ , i++) {
-				int sftcnt = (i << (3 - sft)) & sftmsk;
-				/* Do not store the reserved bbt blocks ! */
-				buf[offs + (i >> sft)] &= ~(msk[dat & 0x03] << sftcnt);
-				dat >>= 2;
-			}
-		}
-
-		memset (&einfo, 0, sizeof (einfo));
-		einfo.mtd = mtd;
-		einfo.addr = (unsigned long) to;
-		einfo.len = 1 << this->bbt_erase_shift;
-		res = nand_erase_nand (mtd, &einfo, 1);
-		if (res < 0) {
-			printk (KERN_WARNING "nand_bbt: Error during block erase: %d\n", res);
-			return res;
-		}
-
-		res = mtd->write_ecc (mtd, to, len, &retlen, buf, &buf[len], &oobinfo);
-		if (res < 0) {
-			printk (KERN_WARNING "nand_bbt: Error while writing bad block table %d\n", res);
-			return res;
-		}
-		printk (KERN_DEBUG "Bad block table written to 0x%08x, version 0x%02X\n",
-			(unsigned int) to, td->version[chip]);
-
-		/* Mark it as used */
-		td->pages[chip] = page;
-	}
-	return 0;
-}
-
-/**
- * nand_memory_bbt - [GENERIC] create a memory based bad block table
- * @mtd:	MTD device structure
- * @bd:		descriptor for the good/bad block search pattern
- *
- * The function creates a memory based bbt by scanning the device
- * for manufacturer / software marked good / bad blocks
-*/
-static int nand_memory_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd)
-{
-	struct nand_chip *this = mtd->priv;
-
-	/* Ensure that we only scan for the pattern and nothing else */
-	bd->options = 0;
-	create_bbt (mtd, this->data_buf, bd, -1);
-	return 0;
-}
-
-/**
- * check_create - [GENERIC] create and write bbt(s) if neccecary
- * @mtd:	MTD device structure
- * @buf:	temporary buffer
- * @bd:		descriptor for the good/bad block search pattern
- *
- * The function checks the results of the previous call to read_bbt
- * and creates / updates the bbt(s) if neccecary
- * Creation is neccecary if no bbt was found for the chip/device
- * Update is neccecary if one of the tables is missing or the
- * version nr. of one table is less than the other
-*/
-static int check_create (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *bd)
-{
-	int i, chips, writeops, chipsel, res;
-	struct nand_chip *this = mtd->priv;
-	struct nand_bbt_descr *td = this->bbt_td;
-	struct nand_bbt_descr *md = this->bbt_md;
-	struct nand_bbt_descr *rd, *rd2;
-
-	/* Do we have a bbt per chip ? */
-	if (td->options & NAND_BBT_PERCHIP)
-		chips = this->numchips;
-	else
-		chips = 1;
-
-	for (i = 0; i < chips; i++) {
-		writeops = 0;
-		rd = NULL;
-		rd2 = NULL;
-		/* Per chip or per device ? */
-		chipsel = (td->options & NAND_BBT_PERCHIP) ? i : -1;
-		/* Mirrored table avilable ? */
-		if (md) {
-			if (td->pages[i] == -1 && md->pages[i] == -1) {
-				writeops = 0x03;
-				goto create;
-			}
-
-			if (td->pages[i] == -1) {
-				rd = md;
-				td->version[i] = md->version[i];
-				writeops = 1;
-				goto writecheck;
-			}
-
-			if (md->pages[i] == -1) {
-				rd = td;
-				md->version[i] = td->version[i];
-				writeops = 2;
-				goto writecheck;
-			}
-
-			if (td->version[i] == md->version[i]) {
-				rd = td;
-				if (!(td->options & NAND_BBT_VERSION))
-					rd2 = md;
-				goto writecheck;
-			}
-
-			if (((int8_t) (td->version[i] - md->version[i])) > 0) {
-				rd = td;
-				md->version[i] = td->version[i];
-				writeops = 2;
-			} else {
-				rd = md;
-				td->version[i] = md->version[i];
-				writeops = 1;
-			}
-
-			goto writecheck;
-
-		} else {
-			if (td->pages[i] == -1) {
-				writeops = 0x01;
-				goto create;
-			}
-			rd = td;
-			goto writecheck;
-		}
-create:
-		/* Create the bad block table by scanning the device ? */
-		if (!(td->options & NAND_BBT_CREATE))
-			continue;
-
-		/* Create the table in memory by scanning the chip(s) */
-		create_bbt (mtd, buf, bd, chipsel);
-
-		td->version[i] = 1;
-		if (md)
-			md->version[i] = 1;
-writecheck:
-		/* read back first ? */
-		if (rd)
-			read_abs_bbt (mtd, buf, rd, chipsel);
-		/* If they weren't versioned, read both. */
-		if (rd2)
-			read_abs_bbt (mtd, buf, rd2, chipsel);
-
-		/* Write the bad block table to the device ? */
-		if ((writeops & 0x01) && (td->options & NAND_BBT_WRITE)) {
-			res = write_bbt (mtd, buf, td, md, chipsel);
-			if (res < 0)
-				return res;
-		}
-
-		/* Write the mirror bad block table to the device ? */
-		if ((writeops & 0x02) && md && (md->options & NAND_BBT_WRITE)) {
-			res = write_bbt (mtd, buf, md, td, chipsel);
-			if (res < 0)
-				return res;
-		}
-	}
-	return 0;
-}
-
-/**
- * mark_bbt_regions - [GENERIC] mark the bad block table regions
- * @mtd:	MTD device structure
- * @td:		bad block table descriptor
- *
- * The bad block table regions are marked as "bad" to prevent
- * accidental erasures / writes. The regions are identified by
- * the mark 0x02.
-*/
-static void mark_bbt_region (struct mtd_info *mtd, struct nand_bbt_descr *td)
-{
-	struct nand_chip *this = mtd->priv;
-	int i, j, chips, block, nrblocks, update;
-	uint8_t oldval, newval;
-
-	/* Do we have a bbt per chip ? */
-	if (td->options & NAND_BBT_PERCHIP) {
-		chips = this->numchips;
-		nrblocks = (int)(this->chipsize >> this->bbt_erase_shift);
-	} else {
-		chips = 1;
-		nrblocks = (int)(mtd->size >> this->bbt_erase_shift);
-	}
-
-	for (i = 0; i < chips; i++) {
-		if ((td->options & NAND_BBT_ABSPAGE) ||
-		    !(td->options & NAND_BBT_WRITE)) {
-		    	if (td->pages[i] == -1) continue;
-			block = td->pages[i] >> (this->bbt_erase_shift - this->page_shift);
-			block <<= 1;
-			oldval = this->bbt[(block >> 3)];
-			newval = oldval | (0x2 << (block & 0x06));
-			this->bbt[(block >> 3)] = newval;
-			if ((oldval != newval) && td->reserved_block_code)
-				nand_update_bbt(mtd, block << (this->bbt_erase_shift - 1));
-			continue;
-		}
-		update = 0;
-		if (td->options & NAND_BBT_LASTBLOCK)
-			block = ((i + 1) * nrblocks) - td->maxblocks;
-		else
-			block = i * nrblocks;
-		block <<= 1;
-		for (j = 0; j < td->maxblocks; j++) {
-			oldval = this->bbt[(block >> 3)];
-			newval = oldval | (0x2 << (block & 0x06));
-			this->bbt[(block >> 3)] = newval;
-			if (oldval != newval) update = 1;
-			block += 2;
-		}
-		/* If we want reserved blocks to be recorded to flash, and some
-		   new ones have been marked, then we need to update the stored
-		   bbts.  This should only happen once. */
-		if (update && td->reserved_block_code)
-			nand_update_bbt(mtd, (block - 2) << (this->bbt_erase_shift - 1));
-	}
-}
-
-/**
- * nand_scan_bbt - [NAND Interface] scan, find, read and maybe create bad block table(s)
- * @mtd:	MTD device structure
- * @bd:		descriptor for the good/bad block search pattern
- *
- * The function checks, if a bad block table(s) is/are already
- * available. If not it scans the device for manufacturer
- * marked good / bad blocks and writes the bad block table(s) to
- * the selected place.
- *
- * The bad block table memory is allocated here. It must be freed
- * by calling the nand_free_bbt function.
- *
-*/
-int nand_scan_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd)
-{
-	struct nand_chip *this = mtd->priv;
-	int len, res = 0;
-	uint8_t *buf;
-	struct nand_bbt_descr *td = this->bbt_td;
-	struct nand_bbt_descr *md = this->bbt_md;
-
-	len = mtd->size >> (this->bbt_erase_shift + 2);
-	/* Allocate memory (2bit per block) */
-	this->bbt = kmalloc (len, GFP_KERNEL);
-	if (!this->bbt) {
-		printk (KERN_ERR "nand_scan_bbt: Out of memory\n");
-		return -ENOMEM;
-	}
-	/* Clear the memory bad block table */
-	memset (this->bbt, 0x00, len);
-
-	/* If no primary table decriptor is given, scan the device
-	 * to build a memory based bad block table
-	 */
-	if (!td)
-		return nand_memory_bbt(mtd, bd);
-
-	/* Allocate a temporary buffer for one eraseblock incl. oob */
-	len = (1 << this->bbt_erase_shift);
-	len += (len >> this->page_shift) * mtd->oobsize;
-	buf = kmalloc (len, GFP_KERNEL);
-	if (!buf) {
-		printk (KERN_ERR "nand_bbt: Out of memory\n");
-		kfree (this->bbt);
-		this->bbt = NULL;
-		return -ENOMEM;
-	}
-
-	/* Is the bbt at a given page ? */
-	if (td->options & NAND_BBT_ABSPAGE) {
-		res = read_abs_bbts (mtd, buf, td, md);
-	} else {
-		/* Search the bad block table using a pattern in oob */
-		res = search_read_bbts (mtd, buf, td, md);
-	}
-
-	if (res)
-		res = check_create (mtd, buf, bd);
-
-	/* Prevent the bbt regions from erasing / writing */
-	mark_bbt_region (mtd, td);
-	if (md)
-		mark_bbt_region (mtd, md);
-
-	kfree (buf);
-	return res;
-}
-
-
-/**
- * nand_update_bbt - [NAND Interface] update bad block table(s)
- * @mtd:	MTD device structure
- * @offs:	the offset of the newly marked block
- *
- * The function updates the bad block table(s)
-*/
-int nand_update_bbt (struct mtd_info *mtd, loff_t offs)
-{
-	struct nand_chip *this = mtd->priv;
-	int len, res = 0, writeops = 0;
-	int chip, chipsel;
-	uint8_t *buf;
-	struct nand_bbt_descr *td = this->bbt_td;
-	struct nand_bbt_descr *md = this->bbt_md;
-
-	if (!this->bbt || !td)
-		return -EINVAL;
-
-	len = mtd->size >> (this->bbt_erase_shift + 2);
-	/* Allocate a temporary buffer for one eraseblock incl. oob */
-	len = (1 << this->bbt_erase_shift);
-	len += (len >> this->page_shift) * mtd->oobsize;
-	buf = kmalloc (len, GFP_KERNEL);
-	if (!buf) {
-		printk (KERN_ERR "nand_update_bbt: Out of memory\n");
-		return -ENOMEM;
-	}
-
-	writeops = md != NULL ? 0x03 : 0x01;
-
-	/* Do we have a bbt per chip ? */
-	if (td->options & NAND_BBT_PERCHIP) {
-		chip = (int) (offs >> this->chip_shift);
-		chipsel = chip;
-	} else {
-		chip = 0;
-		chipsel = -1;
-	}
-
-	td->version[chip]++;
-	if (md)
-		md->version[chip]++;
-
-	/* Write the bad block table to the device ? */
-	if ((writeops & 0x01) && (td->options & NAND_BBT_WRITE)) {
-		res = write_bbt (mtd, buf, td, md, chipsel);
-		if (res < 0)
-			goto out;
-	}
-	/* Write the mirror bad block table to the device ? */
-	if ((writeops & 0x02) && md && (md->options & NAND_BBT_WRITE)) {
-		res = write_bbt (mtd, buf, md, td, chipsel);
-	}
-
-out:
-	kfree (buf);
-	return res;
-}
-
-/* Define some generic bad / good block scan pattern which are used
- * while scanning a device for factory marked good / bad blocks
- *
- * The memory based patterns just
- */
-static uint8_t scan_ff_pattern[] = { 0xff, 0xff };
-
-static struct nand_bbt_descr smallpage_memorybased = {
-	.options = 0,
-	.offs = 5,
-	.len = 1,
-	.pattern = scan_ff_pattern
-};
-
-static struct nand_bbt_descr largepage_memorybased = {
-	.options = 0,
-	.offs = 0,
-	.len = 2,
-	.pattern = scan_ff_pattern
-};
-
-static struct nand_bbt_descr smallpage_flashbased = {
-	.options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
-	.offs = 5,
-	.len = 1,
-	.pattern = scan_ff_pattern
-};
-
-static struct nand_bbt_descr largepage_flashbased = {
-	.options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
-	.offs = 0,
-	.len = 2,
-	.pattern = scan_ff_pattern
-};
-
-static uint8_t scan_agand_pattern[] = { 0x1C, 0x71, 0xC7, 0x1C, 0x71, 0xC7 };
-
-static struct nand_bbt_descr agand_flashbased = {
-	.options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
-	.offs = 0x20,
-	.len = 6,
-	.pattern = scan_agand_pattern
-};
-
-/* Generic flash bbt decriptors
-*/
-static uint8_t bbt_pattern[] = {'B', 'b', 't', '0' };
-static uint8_t mirror_pattern[] = {'1', 't', 'b', 'B' };
-
-static struct nand_bbt_descr bbt_main_descr = {
-	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
-		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
-	.offs =	8,
-	.len = 4,
-	.veroffs = 12,
-	.maxblocks = 4,
-	.pattern = bbt_pattern
-};
-
-static struct nand_bbt_descr bbt_mirror_descr = {
-	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
-		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
-	.offs =	8,
-	.len = 4,
-	.veroffs = 12,
-	.maxblocks = 4,
-	.pattern = mirror_pattern
-};
-
-/**
- * nand_default_bbt - [NAND Interface] Select a default bad block table for the device
- * @mtd:	MTD device structure
- *
- * This function selects the default bad block table
- * support for the device and calls the nand_scan_bbt function
- *
-*/
-int nand_default_bbt (struct mtd_info *mtd)
-{
-	struct nand_chip *this = mtd->priv;
-
-	/* Default for AG-AND. We must use a flash based
-	 * bad block table as the devices have factory marked
-	 * _good_ blocks. Erasing those blocks leads to loss
-	 * of the good / bad information, so we _must_ store
-	 * this information in a good / bad table during
-	 * startup
-	*/
-	if (this->options & NAND_IS_AND) {
-		/* Use the default pattern descriptors */
-		if (!this->bbt_td) {
-			this->bbt_td = &bbt_main_descr;
-			this->bbt_md = &bbt_mirror_descr;
-		}
-		this->options |= NAND_USE_FLASH_BBT;
-		return nand_scan_bbt (mtd, &agand_flashbased);
-	}
-
-
-	/* Is a flash based bad block table requested ? */
-	if (this->options & NAND_USE_FLASH_BBT) {
-		/* Use the default pattern descriptors */
-		if (!this->bbt_td) {
-			this->bbt_td = &bbt_main_descr;
-			this->bbt_md = &bbt_mirror_descr;
-		}
-		if (!this->badblock_pattern) {
-			this->badblock_pattern = (mtd->oobblock > 512) ?
-				&largepage_flashbased : &smallpage_flashbased;
-		}
-	} else {
-		this->bbt_td = NULL;
-		this->bbt_md = NULL;
-		if (!this->badblock_pattern) {
-			this->badblock_pattern = (mtd->oobblock > 512) ?
-				&largepage_memorybased : &smallpage_memorybased;
-		}
-	}
-	return nand_scan_bbt (mtd, this->badblock_pattern);
-}
-
-/**
- * nand_isbad_bbt - [NAND Interface] Check if a block is bad
- * @mtd:	MTD device structure
- * @offs:	offset in the device
- * @allowbbt:	allow access to bad block table region
- *
- */
-int nand_isbad_bbt (struct mtd_info *mtd, loff_t offs, int allowbbt)
-{
-	struct nand_chip *this = mtd->priv;
-	int block;
-	uint8_t	res;
-
-	/* Get block number * 2 */
-	block = (int) (offs >> (this->bbt_erase_shift - 1));
-	res = (this->bbt[block >> 3] >> (block & 0x06)) & 0x03;
-
-	DEBUG (MTD_DEBUG_LEVEL2, "nand_isbad_bbt(): bbt info for offs 0x%08x: (block %d) 0x%02x\n",
-		(unsigned int)offs, res, block >> 1);
-
-	switch ((int)res) {
-	case 0x00:	return 0;
-	case 0x01:	return 1;
-	case 0x02:	return allowbbt ? 0 : 1;
-	}
-	return 1;
-}
-
-#endif