Rewrite of NAND code based on what is in 2.6.12 Linux kernel

Patch by Ladislav Michl, 29 Jun 2005

1 files changed, 2630 insertions, 0 deletions

diff --git a/drivers/nand/nand_base.c b/drivers/nand/nand_base.c
new file mode 100644
index 0000000000..c423512f18
--- /dev/null
+++ b/drivers/nand/nand_base.c
@@ -0,0 +1,2630 @@
+/*
+ *  drivers/mtd/nand.c
+ *
+ *  Overview:
+ *   This is the generic MTD driver for NAND flash devices. It should be
+ *   capable of working with almost all NAND chips currently available.
+ *   Basic support for AG-AND chips is provided.
+ *   
+ *	Additional technical information is available on
+ *	http://www.linux-mtd.infradead.org/tech/nand.html
+ *	
+ *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
+ * 		  2002 Thomas Gleixner (tglx@linutronix.de)
+ *
+ *  02-08-2004  tglx: support for strange chips, which cannot auto increment 
+ *		pages on read / read_oob
+ *
+ *  03-17-2004  tglx: Check ready before auto increment check. Simon Bayes
+ *		pointed this out, as he marked an auto increment capable chip
+ *		as NOAUTOINCR in the board driver.
+ *		Make reads over block boundaries work too
+ *
+ *  04-14-2004	tglx: first working version for 2k page size chips
+ *  
+ *  05-19-2004  tglx: Basic support for Renesas AG-AND chips
+ *
+ *  09-24-2004  tglx: add support for hardware controllers (e.g. ECC) shared
+ *		among multiple independend devices. Suggestions and initial patch
+ *		from Ben Dooks <ben-mtd@fluff.org>
+ *
+ * Credits:
+ *	David Woodhouse for adding multichip support  
+ *	
+ *	Aleph One Ltd. and Toby Churchill Ltd. for supporting the
+ *	rework for 2K page size chips
+ *
+ * TODO:
+ *	Enable cached programming for 2k page size chips
+ *	Check, if mtd->ecctype should be set to MTD_ECC_HW
+ *	if we have HW ecc support.
+ *	The AG-AND chips have nice features for speed improvement,
+ *	which are not supported yet. Read / program 4 pages in one go.
+ *
+ * $Id: nand_base.c,v 1.126 2004/12/13 11:22:25 lavinen 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.
+ *
+ */
+
+/* XXX U-BOOT XXX */
+#if 0
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/mtd/compatmac.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <asm/io.h>
+
+#ifdef CONFIG_MTD_PARTITIONS
+#include <linux/mtd/partitions.h>
+#endif
+
+#else
+
+#include <common.h>
+
+#if (CONFIG_COMMANDS & CFG_CMD_NAND)
+
+#include <malloc.h>
+#include <watchdog.h>
+#include <linux/mtd/compat.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/nand_ecc.h>
+
+#include <asm/io.h>
+#include <asm/errno.h>
+
+#ifdef CONFIG_JFFS2_NAND
+#include <jffs2/jffs2.h>
+#endif
+
+#endif
+
+/* Define default oob placement schemes for large and small page devices */
+static struct nand_oobinfo nand_oob_8 = {
+	.useecc = MTD_NANDECC_AUTOPLACE,
+	.eccbytes = 3,
+	.eccpos = {0, 1, 2},
+	.oobfree = { {3, 2}, {6, 2} }
+};
+
+static struct nand_oobinfo nand_oob_16 = {
+	.useecc = MTD_NANDECC_AUTOPLACE,
+	.eccbytes = 6,
+	.eccpos = {0, 1, 2, 3, 6, 7},
+	.oobfree = { {8, 8} }
+};
+
+static struct nand_oobinfo nand_oob_64 = {
+	.useecc = MTD_NANDECC_AUTOPLACE,
+	.eccbytes = 24,
+	.eccpos = {
+		40, 41, 42, 43, 44, 45, 46, 47, 
+		48, 49, 50, 51, 52, 53, 54, 55, 
+		56, 57, 58, 59, 60, 61, 62, 63},
+	.oobfree = { {2, 38} }
+};
+
+/* This is used for padding purposes in nand_write_oob */
+static u_char ffchars[] = {
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+};
+
+/*
+ * NAND low-level MTD interface functions
+ */
+static void nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len);
+static void nand_read_buf(struct mtd_info *mtd, u_char *buf, int len);
+static int nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len);
+
+static int nand_read (struct mtd_info *mtd, loff_t from, size_t len, size_t * retlen, u_char * buf);
+static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
+			  size_t * retlen, u_char * buf, u_char * eccbuf, struct nand_oobinfo *oobsel);
+static int nand_read_oob (struct mtd_info *mtd, loff_t from, size_t len, size_t * retlen, u_char * buf);
+static int nand_write (struct mtd_info *mtd, loff_t to, size_t len, size_t * retlen, const u_char * buf);
+static int nand_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
+			   size_t * retlen, const u_char * buf, u_char * eccbuf, struct nand_oobinfo *oobsel);
+static int nand_write_oob (struct mtd_info *mtd, loff_t to, size_t len, size_t * retlen, const u_char *buf);
+/* XXX U-BOOT XXX */
+#if 0
+static int nand_writev (struct mtd_info *mtd, const struct kvec *vecs,
+			unsigned long count, loff_t to, size_t * retlen);
+static int nand_writev_ecc (struct mtd_info *mtd, const struct kvec *vecs,
+			unsigned long count, loff_t to, size_t * retlen, u_char *eccbuf, struct nand_oobinfo *oobsel);
+#endif
+static int nand_erase (struct mtd_info *mtd, struct erase_info *instr);
+static void nand_sync (struct mtd_info *mtd);
+
+/* Some internal functions */
+static int nand_write_page (struct mtd_info *mtd, struct nand_chip *this, int page, u_char *oob_buf,
+		struct nand_oobinfo *oobsel, int mode);
+#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
+static int nand_verify_pages (struct mtd_info *mtd, struct nand_chip *this, int page, int numpages, 
+	u_char *oob_buf, struct nand_oobinfo *oobsel, int chipnr, int oobmode);
+#else
+#define nand_verify_pages(...) (0)
+#endif
+		
+static void nand_get_device (struct nand_chip *this, struct mtd_info *mtd, int new_state);
+
+/**
+ * nand_release_device - [GENERIC] release chip
+ * @mtd:	MTD device structure
+ * 
+ * Deselect, release chip lock and wake up anyone waiting on the device 
+ */
+/* XXX U-BOOT XXX */
+#if 0
+static void nand_release_device (struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+
+	/* De-select the NAND device */
+	this->select_chip(mtd, -1);
+	/* Do we have a hardware controller ? */
+	if (this->controller) {
+		spin_lock(&this->controller->lock);
+		this->controller->active = NULL;
+		spin_unlock(&this->controller->lock);
+	}
+	/* Release the chip */
+	spin_lock (&this->chip_lock);
+	this->state = FL_READY;
+	wake_up (&this->wq);
+	spin_unlock (&this->chip_lock);
+}
+#else
+#define nand_release_device(mtd)	do {} while(0)
+#endif
+
+/**
+ * nand_read_byte - [DEFAULT] read one byte from the chip
+ * @mtd:	MTD device structure
+ *
+ * Default read function for 8bit buswith
+ */
+static u_char nand_read_byte(struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+	return readb(this->IO_ADDR_R);
+}
+
+/**
+ * nand_write_byte - [DEFAULT] write one byte to the chip
+ * @mtd:	MTD device structure
+ * @byte:	pointer to data byte to write
+ *
+ * Default write function for 8it buswith
+ */
+static void nand_write_byte(struct mtd_info *mtd, u_char byte)
+{
+	struct nand_chip *this = mtd->priv;
+	writeb(byte, this->IO_ADDR_W);
+}
+
+/**
+ * nand_read_byte16 - [DEFAULT] read one byte endianess aware from the chip
+ * @mtd:	MTD device structure
+ *
+ * Default read function for 16bit buswith with 
+ * endianess conversion
+ */
+static u_char nand_read_byte16(struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+	return (u_char) cpu_to_le16(readw(this->IO_ADDR_R));
+}
+
+/**
+ * nand_write_byte16 - [DEFAULT] write one byte endianess aware to the chip
+ * @mtd:	MTD device structure
+ * @byte:	pointer to data byte to write
+ *
+ * Default write function for 16bit buswith with
+ * endianess conversion
+ */
+static void nand_write_byte16(struct mtd_info *mtd, u_char byte)
+{
+	struct nand_chip *this = mtd->priv;
+	writew(le16_to_cpu((u16) byte), this->IO_ADDR_W);
+}
+
+/**
+ * nand_read_word - [DEFAULT] read one word from the chip
+ * @mtd:	MTD device structure
+ *
+ * Default read function for 16bit buswith without 
+ * endianess conversion
+ */
+static u16 nand_read_word(struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+	return readw(this->IO_ADDR_R);
+}
+
+/**
+ * nand_write_word - [DEFAULT] write one word to the chip
+ * @mtd:	MTD device structure
+ * @word:	data word to write
+ *
+ * Default write function for 16bit buswith without 
+ * endianess conversion
+ */
+static void nand_write_word(struct mtd_info *mtd, u16 word)
+{
+	struct nand_chip *this = mtd->priv;
+	writew(word, this->IO_ADDR_W);
+}
+
+/**
+ * nand_select_chip - [DEFAULT] control CE line
+ * @mtd:	MTD device structure
+ * @chip:	chipnumber to select, -1 for deselect
+ *
+ * Default select function for 1 chip devices.
+ */
+static void nand_select_chip(struct mtd_info *mtd, int chip)
+{
+	struct nand_chip *this = mtd->priv;
+	switch(chip) {
+	case -1:
+		this->hwcontrol(mtd, NAND_CTL_CLRNCE);	
+		break;
+	case 0:
+		this->hwcontrol(mtd, NAND_CTL_SETNCE);
+		break;
+
+	default:
+		BUG();
+	}
+}
+
+/**
+ * nand_write_buf - [DEFAULT] write buffer to chip
+ * @mtd:	MTD device structure
+ * @buf:	data buffer
+ * @len:	number of bytes to write
+ *
+ * Default write function for 8bit buswith
+ */
+static void nand_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i=0; i<len; i++)
+		writeb(buf[i], this->IO_ADDR_W);
+}
+
+/**
+ * nand_read_buf - [DEFAULT] read chip data into buffer 
+ * @mtd:	MTD device structure
+ * @buf:	buffer to store date
+ * @len:	number of bytes to read
+ *
+ * Default read function for 8bit buswith
+ */
+static void nand_read_buf(struct mtd_info *mtd, u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i=0; i<len; i++)
+		buf[i] = readb(this->IO_ADDR_R);
+}
+
+/**
+ * nand_verify_buf - [DEFAULT] Verify chip data against buffer 
+ * @mtd:	MTD device structure
+ * @buf:	buffer containing the data to compare
+ * @len:	number of bytes to compare
+ *
+ * Default verify function for 8bit buswith
+ */
+static int nand_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+
+	for (i=0; i<len; i++)
+		if (buf[i] != readb(this->IO_ADDR_R))
+			return -EFAULT;
+
+	return 0;
+}
+
+/**
+ * nand_write_buf16 - [DEFAULT] write buffer to chip
+ * @mtd:	MTD device structure
+ * @buf:	data buffer
+ * @len:	number of bytes to write
+ *
+ * Default write function for 16bit buswith
+ */
+static void nand_write_buf16(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+	u16 *p = (u16 *) buf;
+	len >>= 1;
+	
+	for (i=0; i<len; i++)
+		writew(p[i], this->IO_ADDR_W);
+		
+}
+
+/**
+ * nand_read_buf16 - [DEFAULT] read chip data into buffer 
+ * @mtd:	MTD device structure
+ * @buf:	buffer to store date
+ * @len:	number of bytes to read
+ *
+ * Default read function for 16bit buswith
+ */
+static void nand_read_buf16(struct mtd_info *mtd, u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+	u16 *p = (u16 *) buf;
+	len >>= 1;
+
+	for (i=0; i<len; i++)
+		p[i] = readw(this->IO_ADDR_R);
+}
+
+/**
+ * nand_verify_buf16 - [DEFAULT] Verify chip data against buffer 
+ * @mtd:	MTD device structure
+ * @buf:	buffer containing the data to compare
+ * @len:	number of bytes to compare
+ *
+ * Default verify function for 16bit buswith
+ */
+static int nand_verify_buf16(struct mtd_info *mtd, const u_char *buf, int len)
+{
+	int i;
+	struct nand_chip *this = mtd->priv;
+	u16 *p = (u16 *) buf;
+	len >>= 1;
+
+	for (i=0; i<len; i++)
+		if (p[i] != readw(this->IO_ADDR_R))
+			return -EFAULT;
+
+	return 0;
+}
+
+/**
+ * nand_block_bad - [DEFAULT] Read bad block marker from the chip
+ * @mtd:	MTD device structure
+ * @ofs:	offset from device start
+ * @getchip:	0, if the chip is already selected
+ *
+ * Check, if the block is bad. 
+ */
+static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
+{
+	int page, chipnr, res = 0;
+	struct nand_chip *this = mtd->priv;
+	u16 bad;
+
+	if (getchip) {
+		page = (int)(ofs >> this->page_shift);
+		chipnr = (int)(ofs >> this->chip_shift);
+
+		/* Grab the lock and see if the device is available */
+		nand_get_device (this, mtd, FL_READING);
+
+		/* Select the NAND device */
+		this->select_chip(mtd, chipnr);
+	} else 
+		page = (int) ofs;	
+
+	if (this->options & NAND_BUSWIDTH_16) {
+		this->cmdfunc (mtd, NAND_CMD_READOOB, this->badblockpos & 0xFE, page & this->pagemask);
+		bad = cpu_to_le16(this->read_word(mtd));
+		if (this->badblockpos & 0x1)
+			bad >>= 1;
+		if ((bad & 0xFF) != 0xff)
+			res = 1;
+	} else {
+		this->cmdfunc (mtd, NAND_CMD_READOOB, this->badblockpos, page & this->pagemask);
+		if (this->read_byte(mtd) != 0xff)
+			res = 1;
+	}
+		
+	if (getchip) {
+		/* Deselect and wake up anyone waiting on the device */
+		nand_release_device(mtd);
+	}	
+	
+	return res;
+}
+
+/**
+ * nand_default_block_markbad - [DEFAULT] mark a block bad
+ * @mtd:	MTD device structure
+ * @ofs:	offset from device start
+ *
+ * This is the default implementation, which can be overridden by
+ * a hardware specific driver.
+*/
+static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
+{
+	struct nand_chip *this = mtd->priv;
+	u_char buf[2] = {0, 0};
+	size_t	retlen;
+	int block;
+	
+	/* Get block number */
+	block = ((int) ofs) >> this->bbt_erase_shift;
+	this->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
+
+	/* Do we have a flash based bad block table ? */
+	if (this->options & NAND_USE_FLASH_BBT)
+		return nand_update_bbt (mtd, ofs);
+		
+	/* We write two bytes, so we dont have to mess with 16 bit access */
+	ofs += mtd->oobsize + (this->badblockpos & ~0x01);
+	return nand_write_oob (mtd, ofs , 2, &retlen, buf);
+}
+
+/** 
+ * nand_check_wp - [GENERIC] check if the chip is write protected
+ * @mtd:	MTD device structure
+ * Check, if the device is write protected 
+ *
+ * The function expects, that the device is already selected 
+ */
+static int nand_check_wp (struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+	/* Check the WP bit */
+	this->cmdfunc (mtd, NAND_CMD_STATUS, -1, -1);
+	return (this->read_byte(mtd) & 0x80) ? 0 : 1; 
+}
+
+/**
+ * nand_block_checkbad - [GENERIC] Check if a block is marked bad
+ * @mtd:	MTD device structure
+ * @ofs:	offset from device start
+ * @getchip:	0, if the chip is already selected
+ * @allowbbt:	1, if its allowed to access the bbt area
+ *
+ * Check, if the block is bad. Either by reading the bad block table or
+ * calling of the scan function.
+ */
+static int nand_block_checkbad (struct mtd_info *mtd, loff_t ofs, int getchip, int allowbbt)
+{
+	struct nand_chip *this = mtd->priv;
+	
+	if (!this->bbt)
+		return this->block_bad(mtd, ofs, getchip);
+	
+	/* Return info from the table */
+	return nand_isbad_bbt (mtd, ofs, allowbbt);
+}
+
+/**
+ * nand_command - [DEFAULT] Send command to NAND device
+ * @mtd:	MTD device structure
+ * @command:	the command to be sent
+ * @column:	the column address for this command, -1 if none
+ * @page_addr:	the page address for this command, -1 if none
+ *
+ * Send command to NAND device. This function is used for small page
+ * devices (256/512 Bytes per page)
+ */
+static void nand_command (struct mtd_info *mtd, unsigned command, int column, int page_addr)
+{
+	register struct nand_chip *this = mtd->priv;
+
+	/* Begin command latch cycle */
+	this->hwcontrol(mtd, NAND_CTL_SETCLE);
+	/*
+	 * Write out the command to the device.
+	 */
+	if (command == NAND_CMD_SEQIN) {
+		int readcmd;
+
+		if (column >= mtd->oobblock) {
+			/* OOB area */
+			column -= mtd->oobblock;
+			readcmd = NAND_CMD_READOOB;
+		} else if (column < 256) {
+			/* First 256 bytes --> READ0 */
+			readcmd = NAND_CMD_READ0;
+		} else {
+			column -= 256;
+			readcmd = NAND_CMD_READ1;
+		}
+		this->write_byte(mtd, readcmd);
+	}
+	this->write_byte(mtd, command);
+
+	/* Set ALE and clear CLE to start address cycle */
+	this->hwcontrol(mtd, NAND_CTL_CLRCLE);
+
+	if (column != -1 || page_addr != -1) {
+		this->hwcontrol(mtd, NAND_CTL_SETALE);
+
+		/* Serially input address */
+		if (column != -1) {
+			/* Adjust columns for 16 bit buswidth */
+			if (this->options & NAND_BUSWIDTH_16)
+				column >>= 1;
+			this->write_byte(mtd, column);
+		}
+		if (page_addr != -1) {
+			this->write_byte(mtd, (unsigned char) (page_addr & 0xff));
+			this->write_byte(mtd, (unsigned char) ((page_addr >> 8) & 0xff));
+			/* One more address cycle for devices > 32MiB */
+			if (this->chipsize > (32 << 20))
+				this->write_byte(mtd, (unsigned char) ((page_addr >> 16) & 0x0f));
+		}
+		/* Latch in address */
+		this->hwcontrol(mtd, NAND_CTL_CLRALE);
+	}
+	
+	/* 
+	 * program and erase have their own busy handlers 
+	 * status and sequential in needs no delay
+	*/
+	switch (command) {
+			
+	case NAND_CMD_PAGEPROG:
+	case NAND_CMD_ERASE1:
+	case NAND_CMD_ERASE2:
+	case NAND_CMD_SEQIN:
+	case NAND_CMD_STATUS:
+		return;
+
+	case NAND_CMD_RESET:
+		if (this->dev_ready)	
+			break;
+		udelay(this->chip_delay);
+		this->hwcontrol(mtd, NAND_CTL_SETCLE);
+		this->write_byte(mtd, NAND_CMD_STATUS);
+		this->hwcontrol(mtd, NAND_CTL_CLRCLE);
+		while ( !(this->read_byte(mtd) & 0x40));
+		return;
+
+	/* This applies to read commands */	
+	default:
+		/* 
+		 * If we don't have access to the busy pin, we apply the given
+		 * command delay
+		*/
+		if (!this->dev_ready) {
+			udelay (this->chip_delay);
+			return;
+		}	
+	}
+	
+	/* Apply this short delay always to ensure that we do wait tWB in
+	 * any case on any machine. */
+	ndelay (100);
+	/* wait until command is processed */
+	while (!this->dev_ready(mtd));
+}
+
+/**
+ * nand_command_lp - [DEFAULT] Send command to NAND large page device
+ * @mtd:	MTD device structure
+ * @command:	the command to be sent
+ * @column:	the column address for this command, -1 if none
+ * @page_addr:	the page address for this command, -1 if none
+ *
+ * Send command to NAND device. This is the version for the new large page devices
+ * We dont have the seperate regions as we have in the small page devices.
+ * We must emulate NAND_CMD_READOOB to keep the code compatible.
+ *
+ */
+static void nand_command_lp (struct mtd_info *mtd, unsigned command, int column, int page_addr)
+{
+	register struct nand_chip *this = mtd->priv;
+
+	/* Emulate NAND_CMD_READOOB */
+	if (command == NAND_CMD_READOOB) {
+		column += mtd->oobblock;
+		command = NAND_CMD_READ0;
+	}
+	
+		
+	/* Begin command latch cycle */
+	this->hwcontrol(mtd, NAND_CTL_SETCLE);
+	/* Write out the command to the device. */
+	this->write_byte(mtd, command);
+	/* End command latch cycle */
+	this->hwcontrol(mtd, NAND_CTL_CLRCLE);
+
+	if (column != -1 || page_addr != -1) {
+		this->hwcontrol(mtd, NAND_CTL_SETALE);
+
+		/* Serially input address */
+		if (column != -1) {
+			/* Adjust columns for 16 bit buswidth */
+			if (this->options & NAND_BUSWIDTH_16)
+				column >>= 1;
+			this->write_byte(mtd, column & 0xff);
+			this->write_byte(mtd, column >> 8);
+		}	
+		if (page_addr != -1) {
+			this->write_byte(mtd, (unsigned char) (page_addr & 0xff));
+			this->write_byte(mtd, (unsigned char) ((page_addr >> 8) & 0xff));
+			/* One more address cycle for devices > 128MiB */
+			if (this->chipsize > (128 << 20))
+				this->write_byte(mtd, (unsigned char) ((page_addr >> 16) & 0xff));
+		}
+		/* Latch in address */
+		this->hwcontrol(mtd, NAND_CTL_CLRALE);
+	}
+	
+	/* 
+	 * program and erase have their own busy handlers 
+	 * status and sequential in needs no delay
+	*/
+	switch (command) {
+			
+	case NAND_CMD_CACHEDPROG:
+	case NAND_CMD_PAGEPROG:
+	case NAND_CMD_ERASE1:
+	case NAND_CMD_ERASE2:
+	case NAND_CMD_SEQIN:
+	case NAND_CMD_STATUS:
+		return;
+
+
+	case NAND_CMD_RESET:
+		if (this->dev_ready)	
+			break;
+		udelay(this->chip_delay);
+		this->hwcontrol(mtd, NAND_CTL_SETCLE);
+		this->write_byte(mtd, NAND_CMD_STATUS);
+		this->hwcontrol(mtd, NAND_CTL_CLRCLE);
+		while ( !(this->read_byte(mtd) & 0x40));
+		return;
+
+	case NAND_CMD_READ0:
+		/* Begin command latch cycle */
+		this->hwcontrol(mtd, NAND_CTL_SETCLE);
+		/* Write out the start read command */
+		this->write_byte(mtd, NAND_CMD_READSTART);
+		/* End command latch cycle */
+		this->hwcontrol(mtd, NAND_CTL_CLRCLE);
+		/* Fall through into ready check */
+		
+	/* This applies to read commands */	
+	default:
+		/* 
+		 * If we don't have access to the busy pin, we apply the given
+		 * command delay
+		*/
+		if (!this->dev_ready) {
+			udelay (this->chip_delay);
+			return;
+		}	
+	}
+	
+	/* Apply this short delay always to ensure that we do wait tWB in
+	 * any case on any machine. */
+	ndelay (100);
+	/* wait until command is processed */
+	while (!this->dev_ready(mtd));
+}
+
+/**
+ * nand_get_device - [GENERIC] Get chip for selected access
+ * @this:	the nand chip descriptor
+ * @mtd:	MTD device structure
+ * @new_state:	the state which is requested 
+ *
+ * Get the device and lock it for exclusive access
+ */
+/* XXX U-BOOT XXX */
+#if 0
+static void nand_get_device (struct nand_chip *this, struct mtd_info *mtd, int new_state)
+{
+	struct nand_chip *active = this;
+
+	DECLARE_WAITQUEUE (wait, current);
+
+	/* 
+	 * Grab the lock and see if the device is available 
+	*/
+retry:
+	/* Hardware controller shared among independend devices */
+	if (this->controller) {
+		spin_lock (&this->controller->lock);
+		if (this->controller->active)
+			active = this->controller->active;
+		else
+			this->controller->active = this;
+		spin_unlock (&this->controller->lock);
+	}
+	
+	if (active == this) {
+		spin_lock (&this->chip_lock);
+		if (this->state == FL_READY) {
+			this->state = new_state;
+			spin_unlock (&this->chip_lock);
+			return;
+		}
+	}	
+	set_current_state (TASK_UNINTERRUPTIBLE);
+	add_wait_queue (&active->wq, &wait);
+	spin_unlock (&active->chip_lock);
+	schedule ();
+	remove_wait_queue (&active->wq, &wait);
+	goto retry;
+}
+#else
+static void nand_get_device (struct nand_chip *this, struct mtd_info *mtd, int new_state) {}
+#endif
+
+/**
+ * nand_wait - [DEFAULT]  wait until the command is done
+ * @mtd:	MTD device structure
+ * @this:	NAND chip structure
+ * @state:	state to select the max. timeout value
+ *
+ * Wait for command done. This applies to erase and program only
+ * Erase can take up to 400ms and program up to 20ms according to 
+ * general NAND and SmartMedia specs
+ *
+*/
+/* XXX U-BOOT XXX */
+#if 0
+static int nand_wait(struct mtd_info *mtd, struct nand_chip *this, int state)
+{
+	unsigned long	timeo = jiffies;
+	int	status;
+	
+	if (state == FL_ERASING)
+		 timeo += (HZ * 400) / 1000;
+	else
+		 timeo += (HZ * 20) / 1000;
+
+	/* Apply this short delay always to ensure that we do wait tWB in
+	 * any case on any machine. */
+	ndelay (100);
+
+	if ((state == FL_ERASING) && (this->options & NAND_IS_AND))
+		this->cmdfunc (mtd, NAND_CMD_STATUS_MULTI, -1, -1);
+	else	
+		this->cmdfunc (mtd, NAND_CMD_STATUS, -1, -1);
+
+	while (time_before(jiffies, timeo)) {		
+		/* Check, if we were interrupted */
+		if (this->state != state)
+			return 0;
+
+		if (this->dev_ready) {
+			if (this->dev_ready(mtd))
+				break;	
+		} else {
+			if (this->read_byte(mtd) & NAND_STATUS_READY)
+				break;
+		}
+		yield ();
+	}
+	status = (int) this->read_byte(mtd);
+	return status;
+
+	return 0;
+}
+#else
+static int nand_wait(struct mtd_info *mtd, struct nand_chip *this, int state)
+{
+	/* TODO */
+	return 0;
+}
+#endif
+
+/**
+ * nand_write_page - [GENERIC] write one page
+ * @mtd:	MTD device structure
+ * @this:	NAND chip structure
+ * @page: 	startpage inside the chip, must be called with (page & this->pagemask)
+ * @oob_buf:	out of band data buffer
+ * @oobsel:	out of band selecttion structre
+ * @cached:	1 = enable cached programming if supported by chip
+ *
+ * Nand_page_program function is used for write and writev !
+ * This function will always program a full page of data
+ * If you call it with a non page aligned buffer, you're lost :)
+ *
+ * Cached programming is not supported yet.
+ */
+static int nand_write_page (struct mtd_info *mtd, struct nand_chip *this, int page, 
+	u_char *oob_buf,  struct nand_oobinfo *oobsel, int cached)
+{
+	int 	i, status;
+	u_char	ecc_code[32];
+	int	eccmode = oobsel->useecc ? this->eccmode : NAND_ECC_NONE;
+	int  	*oob_config = oobsel->eccpos;
+	int	datidx = 0, eccidx = 0, eccsteps = this->eccsteps;
+	int	eccbytes = 0;
+	
+	/* FIXME: Enable cached programming */
+	cached = 0;
+	
+	/* Send command to begin auto page programming */
+	this->cmdfunc (mtd, NAND_CMD_SEQIN, 0x00, page);
+
+	/* Write out complete page of data, take care of eccmode */
+	switch (eccmode) {
+	/* No ecc, write all */
+	case NAND_ECC_NONE:
+		printk (KERN_WARNING "Writing data without ECC to NAND-FLASH is not recommended\n");
+		this->write_buf(mtd, this->data_poi, mtd->oobblock);
+		break;
+		
+	/* Software ecc 3/256, write all */
+	case NAND_ECC_SOFT:
+		for (; eccsteps; eccsteps--) {
+			this->calculate_ecc(mtd, &this->data_poi[datidx], ecc_code);
+			for (i = 0; i < 3; i++, eccidx++)
+				oob_buf[oob_config[eccidx]] = ecc_code[i];
+			datidx += this->eccsize;
+		}
+		this->write_buf(mtd, this->data_poi, mtd->oobblock);
+		break;
+	default:
+		eccbytes = this->eccbytes;
+		for (; eccsteps; eccsteps--) {
+			/* enable hardware ecc logic for write */
+			this->enable_hwecc(mtd, NAND_ECC_WRITE);
+			this->write_buf(mtd, &this->data_poi[datidx], this->eccsize);
+			this->calculate_ecc(mtd, &this->data_poi[datidx], ecc_code);
+			for (i = 0; i < eccbytes; i++, eccidx++)
+				oob_buf[oob_config[eccidx]] = ecc_code[i];
+			/* If the hardware ecc provides syndromes then
+			 * the ecc code must be written immidiately after
+			 * the data bytes (words) */
+			if (this->options & NAND_HWECC_SYNDROME)
+				this->write_buf(mtd, ecc_code, eccbytes);
+			datidx += this->eccsize;
+		}
+		break;
+	}
+										
+	/* Write out OOB data */
+	if (this->options & NAND_HWECC_SYNDROME)
+		this->write_buf(mtd, &oob_buf[oobsel->eccbytes], mtd->oobsize - oobsel->eccbytes);
+	else 
+		this->write_buf(mtd, oob_buf, mtd->oobsize);
+
+	/* Send command to actually program the data */
+	this->cmdfunc (mtd, cached ? NAND_CMD_CACHEDPROG : NAND_CMD_PAGEPROG, -1, -1);
+
+	if (!cached) {
+		/* call wait ready function */
+		status = this->waitfunc (mtd, this, FL_WRITING);
+		/* See if device thinks it succeeded */
+		if (status & 0x01) {
+			DEBUG (MTD_DEBUG_LEVEL0, "%s: " "Failed write, page 0x%08x, ", __FUNCTION__, page);
+			return -EIO;
+		}
+	} else {
+		/* FIXME: Implement cached programming ! */
+		/* wait until cache is ready*/
+		// status = this->waitfunc (mtd, this, FL_CACHEDRPG);
+	}
+	return 0;	
+}
+
+#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
+/**
+ * nand_verify_pages - [GENERIC] verify the chip contents after a write
+ * @mtd:	MTD device structure
+ * @this:	NAND chip structure
+ * @page: 	startpage inside the chip, must be called with (page & this->pagemask)
+ * @numpages:	number of pages to verify
+ * @oob_buf:	out of band data buffer
+ * @oobsel:	out of band selecttion structre
+ * @chipnr:	number of the current chip
+ * @oobmode:	1 = full buffer verify, 0 = ecc only
+ *
+ * The NAND device assumes that it is always writing to a cleanly erased page.
+ * Hence, it performs its internal write verification only on bits that 
+ * transitioned from 1 to 0. The device does NOT verify the whole page on a
+ * byte by byte basis. It is possible that the page was not completely erased 
+ * or the page is becoming unusable due to wear. The read with ECC would catch 
+ * the error later when the ECC page check fails, but we would rather catch 
+ * it early in the page write stage. Better to write no data than invalid data.
+ */
+static int nand_verify_pages (struct mtd_info *mtd, struct nand_chip *this, int page, int numpages, 
+	u_char *oob_buf, struct nand_oobinfo *oobsel, int chipnr, int oobmode)
+{
+	int 	i, j, datidx = 0, oobofs = 0, res = -EIO;
+	int	eccsteps = this->eccsteps;
+	int	hweccbytes; 
+	u_char 	oobdata[64];
+
+	hweccbytes = (this->options & NAND_HWECC_SYNDROME) ? (oobsel->eccbytes / eccsteps) : 0;
+
+	/* Send command to read back the first page */
+	this->cmdfunc (mtd, NAND_CMD_READ0, 0, page);
+
+	for(;;) {
+		for (j = 0; j < eccsteps; j++) {
+			/* Loop through and verify the data */
+			if (this->verify_buf(mtd, &this->data_poi[datidx], mtd->eccsize)) {
+				DEBUG (MTD_DEBUG_LEVEL0, "%s: " "Failed write verify, page 0x%08x ", __FUNCTION__, page);
+				goto out;
+			}
+			datidx += mtd->eccsize;
+			/* Have we a hw generator layout ? */
+			if (!hweccbytes)
+				continue;
+			if (this->verify_buf(mtd, &this->oob_buf[oobofs], hweccbytes)) {
+				DEBUG (MTD_DEBUG_LEVEL0, "%s: " "Failed write verify, page 0x%08x ", __FUNCTION__, page);
+				goto out;
+			}
+			oobofs += hweccbytes;
+		}
+
+		/* check, if we must compare all data or if we just have to
+		 * compare the ecc bytes
+		 */
+		if (oobmode) {
+			if (this->verify_buf(mtd, &oob_buf[oobofs], mtd->oobsize - hweccbytes * eccsteps)) {
+				DEBUG (MTD_DEBUG_LEVEL0, "%s: " "Failed write verify, page 0x%08x ", __FUNCTION__, page);
+				goto out;
+			}
+		} else {
+			/* Read always, else autoincrement fails */
+			this->read_buf(mtd, oobdata, mtd->oobsize - hweccbytes * eccsteps);
+
+			if (oobsel->useecc != MTD_NANDECC_OFF && !hweccbytes) {
+				int ecccnt = oobsel->eccbytes;
+		
+				for (i = 0; i < ecccnt; i++) {
+					int idx = oobsel->eccpos[i];
+					if (oobdata[idx] != oob_buf[oobofs + idx] ) {
+						DEBUG (MTD_DEBUG_LEVEL0,
+					       	"%s: Failed ECC write "
+						"verify, page 0x%08x, " "%6i bytes were succesful\n", __FUNCTION__, page, i);
+						goto out;
+					}
+				}
+			}	
+		}
+		oobofs += mtd->oobsize - hweccbytes * eccsteps;
+		page++;
+		numpages--;
+
+		/* Apply delay or wait for ready/busy pin 
+		 * Do this before the AUTOINCR check, so no problems
+		 * arise if a chip which does auto increment
+		 * is marked as NOAUTOINCR by the board driver.
+		 * Do this also before returning, so the chip is
+		 * ready for the next command.
+		*/
+		if (!this->dev_ready) 
+			udelay (this->chip_delay);
+		else
+			while (!this->dev_ready(mtd));	
+
+		/* All done, return happy */
+		if (!numpages)
+			return 0;
+		
+			
+		/* Check, if the chip supports auto page increment */ 
+		if (!NAND_CANAUTOINCR(this))
+			this->cmdfunc (mtd, NAND_CMD_READ0, 0x00, page);
+	}
+	/* 
+	 * Terminate the read command. We come here in case of an error
+	 * So we must issue a reset command.
+	 */
+out:	 
+	this->cmdfunc (mtd, NAND_CMD_RESET, -1, -1);
+	return res;
+}
+#endif
+
+/**
+ * nand_read - [MTD Interface] MTD compability function for nand_read_ecc
+ * @mtd:	MTD device structure
+ * @from:	offset to read from
+ * @len:	number of bytes to read
+ * @retlen:	pointer to variable to store the number of read bytes
+ * @buf:	the databuffer to put data
+ *
+ * This function simply calls nand_read_ecc with oob buffer and oobsel = NULL
+*/
+static int nand_read (struct mtd_info *mtd, loff_t from, size_t len, size_t * retlen, u_char * buf)
+{
+	return nand_read_ecc (mtd, from, len, retlen, buf, NULL, NULL);
+}			   
+
+
+/**
+ * nand_read_ecc - [MTD Interface] Read data with ECC
+ * @mtd:	MTD device structure
+ * @from:	offset to read from
+ * @len:	number of bytes to read
+ * @retlen:	pointer to variable to store the number of read bytes
+ * @buf:	the databuffer to put data
+ * @oob_buf:	filesystem supplied oob data buffer
+ * @oobsel:	oob selection structure
+ *
+ * NAND read with ECC
+ */
+static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
+			  size_t * retlen, u_char * buf, u_char * oob_buf, struct nand_oobinfo *oobsel)
+{
+	int i, j, col, realpage, page, end, ecc, chipnr, sndcmd = 1;
+	int read = 0, oob = 0, ecc_status = 0, ecc_failed = 0;
+	struct nand_chip *this = mtd->priv;
+	u_char *data_poi, *oob_data = oob_buf;
+	u_char ecc_calc[32];
+	u_char ecc_code[32];
+        int eccmode, eccsteps;
+	int	*oob_config, datidx;
+	int	blockcheck = (1 << (this->phys_erase_shift - this->page_shift)) - 1;
+	int	eccbytes;
+	int	compareecc = 1;
+	int	oobreadlen;
+
+
+	DEBUG (MTD_DEBUG_LEVEL3, "nand_read_ecc: from = 0x%08x, len = %i\n", (unsigned int) from, (int) len);
+
+	/* Do not allow reads past end of device */
+	if ((from + len) > mtd->size) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_read_ecc: Attempt read beyond end of device\n");
+		*retlen = 0;
+		return -EINVAL;
+	}
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd ,FL_READING);
+
+	/* use userspace supplied oobinfo, if zero */
+	if (oobsel == NULL)
+		oobsel = &mtd->oobinfo;
+	
+	/* Autoplace of oob data ? Use the default placement scheme */
+	if (oobsel->useecc == MTD_NANDECC_AUTOPLACE)
+		oobsel = this->autooob;
+		
+	eccmode = oobsel->useecc ? this->eccmode : NAND_ECC_NONE;
+	oob_config = oobsel->eccpos;
+
+	/* Select the NAND device */
+	chipnr = (int)(from >> this->chip_shift);
+	this->select_chip(mtd, chipnr);
+
+	/* First we calculate the starting page */
+	realpage = (int) (from >> this->page_shift);
+	page = realpage & this->pagemask;
+
+	/* Get raw starting column */
+	col = from & (mtd->oobblock - 1);
+
+	end = mtd->oobblock;
+	ecc = this->eccsize;
+	eccbytes = this->eccbytes;
+	
+	if ((eccmode == NAND_ECC_NONE) || (this->options & NAND_HWECC_SYNDROME))
+		compareecc = 0;
+
+	oobreadlen = mtd->oobsize;
+	if (this->options & NAND_HWECC_SYNDROME) 
+		oobreadlen -= oobsel->eccbytes;
+
+	/* Loop until all data read */
+	while (read < len) {
+		
+		int aligned = (!col && (len - read) >= end);
+		/* 
+		 * If the read is not page aligned, we have to read into data buffer
+		 * due to ecc, else we read into return buffer direct
+		 */
+		if (aligned)
+			data_poi = &buf[read];
+		else 
+			data_poi = this->data_buf;
+		
+		/* Check, if we have this page in the buffer 
+		 *
+		 * FIXME: Make it work when we must provide oob data too,
+		 * check the usage of data_buf oob field
+		 */
+		if (realpage == this->pagebuf && !oob_buf) {
+			/* aligned read ? */
+			if (aligned)
+				memcpy (data_poi, this->data_buf, end);
+			goto readdata;
+		}
+
+		/* Check, if we must send the read command */
+		if (sndcmd) {
+			this->cmdfunc (mtd, NAND_CMD_READ0, 0x00, page);
+			sndcmd = 0;
+		}	
+
+		/* get oob area, if we have no oob buffer from fs-driver */
+		if (!oob_buf || oobsel->useecc == MTD_NANDECC_AUTOPLACE ||
+			oobsel->useecc == MTD_NANDECC_AUTOPL_USR)
+			oob_data = &this->data_buf[end];
+
+		eccsteps = this->eccsteps;
+		
+		switch (eccmode) {
+		case NAND_ECC_NONE: {	/* No ECC, Read in a page */
+/* XXX U-BOOT XXX */
+#if 0
+			static unsigned long lastwhinge = 0;
+			if ((lastwhinge / HZ) != (jiffies / HZ)) {
+				printk (KERN_WARNING "Reading data from NAND FLASH without ECC is not recommended\n");
+				lastwhinge = jiffies;
+			}
+#else
+			puts("Reading data from NAND FLASH without ECC is not recommended\n");
+#endif
+			this->read_buf(mtd, data_poi, end);
+			break;
+		}
+			
+		case NAND_ECC_SOFT:	/* Software ECC 3/256: Read in a page + oob data */
+			this->read_buf(mtd, data_poi, end);
+			for (i = 0, datidx = 0; eccsteps; eccsteps--, i+=3, datidx += ecc) 
+				this->calculate_ecc(mtd, &data_poi[datidx], &ecc_calc[i]);
+			break;	
+
+		default:
+			for (i = 0, datidx = 0; eccsteps; eccsteps--, i+=eccbytes, datidx += ecc) {
+				this->enable_hwecc(mtd, NAND_ECC_READ);
+				this->read_buf(mtd, &data_poi[datidx], ecc);
+
+				/* HW ecc with syndrome calculation must read the
+				 * syndrome from flash immidiately after the data */
+				if (!compareecc) {
+					/* Some hw ecc generators need to know when the
+					 * syndrome is read from flash */
+					this->enable_hwecc(mtd, NAND_ECC_READSYN);
+					this->read_buf(mtd, &oob_data[i], eccbytes);
+					/* We calc error correction directly, it checks the hw
+					 * generator for an error, reads back the syndrome and
+					 * does the error correction on the fly */
+					if (this->correct_data(mtd, &data_poi[datidx], &oob_data[i], &ecc_code[i]) == -1) {
+						DEBUG (MTD_DEBUG_LEVEL0, "nand_read_ecc: " 
+							"Failed ECC read, page 0x%08x on chip %d\n", page, chipnr);
+						ecc_failed++;
+					}
+				} else {
+					this->calculate_ecc(mtd, &data_poi[datidx], &ecc_calc[i]);
+				}	
+			}
+			break;						
+		}
+
+		/* read oobdata */
+		this->read_buf(mtd, &oob_data[mtd->oobsize - oobreadlen], oobreadlen);
+
+		/* Skip ECC check, if not requested (ECC_NONE or HW_ECC with syndromes) */
+		if (!compareecc)
+			goto readoob;	
+		
+		/* Pick the ECC bytes out of the oob data */
+		for (j = 0; j < oobsel->eccbytes; j++)
+			ecc_code[j] = oob_data[oob_config[j]];
+
+		/* correct data, if neccecary */
+		for (i = 0, j = 0, datidx = 0; i < this->eccsteps; i++, datidx += ecc) {
+			ecc_status = this->correct_data(mtd, &data_poi[datidx], &ecc_code[j], &ecc_calc[j]);
+			
+			/* Get next chunk of ecc bytes */
+			j += eccbytes;
+			
+			/* Check, if we have a fs supplied oob-buffer, 
+			 * This is the legacy mode. Used by YAFFS1
+			 * Should go away some day
+			 */
+			if (oob_buf && oobsel->useecc == MTD_NANDECC_PLACE) { 
+				int *p = (int *)(&oob_data[mtd->oobsize]);
+				p[i] = ecc_status;
+			}
+			
+			if (ecc_status == -1) {	
+				DEBUG (MTD_DEBUG_LEVEL0, "nand_read_ecc: " "Failed ECC read, page 0x%08x\n", page);
+				ecc_failed++;
+			}
+		}		
+
+	readoob:
+		/* check, if we have a fs supplied oob-buffer */
+		if (oob_buf) {
+			/* without autoplace. Legacy mode used by YAFFS1 */
+			switch(oobsel->useecc) {
+			case MTD_NANDECC_AUTOPLACE:
+			case MTD_NANDECC_AUTOPL_USR:
+				/* Walk through the autoplace chunks */
+				for (i = 0, j = 0; j < mtd->oobavail; i++) {
+					int from = oobsel->oobfree[i][0];
+					int num = oobsel->oobfree[i][1];
+					memcpy(&oob_buf[oob], &oob_data[from], num);
+					j+= num;
+				}
+				oob += mtd->oobavail;
+				break;
+			case MTD_NANDECC_PLACE:
+				/* YAFFS1 legacy mode */
+				oob_data += this->eccsteps * sizeof (int);
+			default:
+				oob_data += mtd->oobsize;
+			}
+		}
+	readdata:
+		/* Partial page read, transfer data into fs buffer */
+		if (!aligned) { 
+			for (j = col; j < end && read < len; j++)
+				buf[read++] = data_poi[j];
+			this->pagebuf = realpage;	
+		} else		
+			read += mtd->oobblock;
+
+		/* Apply delay or wait for ready/busy pin 
+		 * Do this before the AUTOINCR check, so no problems
+		 * arise if a chip which does auto increment
+		 * is marked as NOAUTOINCR by the board driver.
+		*/
+		if (!this->dev_ready) 
+			udelay (this->chip_delay);
+		else
+			while (!this->dev_ready(mtd));	
+			
+		if (read == len)
+			break;	
+
+		/* For subsequent reads align to page boundary. */
+		col = 0;
+		/* Increment page address */
+		realpage++;
+
+		page = realpage & this->pagemask;
+		/* Check, if we cross a chip boundary */
+		if (!page) {
+			chipnr++;
+			this->select_chip(mtd, -1);
+			this->select_chip(mtd, chipnr);
+		}
+		/* Check, if the chip supports auto page increment 
+		 * or if we have hit a block boundary. 
+		*/ 
+		if (!NAND_CANAUTOINCR(this) || !(page & blockcheck))
+			sndcmd = 1;				
+	}
+
+	/* Deselect and wake up anyone waiting on the device */
+	nand_release_device(mtd);
+
+	/*
+	 * Return success, if no ECC failures, else -EBADMSG
+	 * fs driver will take care of that, because
+	 * retlen == desired len and result == -EBADMSG
+	 */
+	*retlen = read;
+	return ecc_failed ? -EBADMSG : 0;
+}
+
+/**
+ * nand_read_oob - [MTD Interface] NAND read out-of-band
+ * @mtd:	MTD device structure
+ * @from:	offset to read from
+ * @len:	number of bytes to read
+ * @retlen:	pointer to variable to store the number of read bytes
+ * @buf:	the databuffer to put data
+ *
+ * NAND read out-of-band data from the spare area
+ */
+static int nand_read_oob (struct mtd_info *mtd, loff_t from, size_t len, size_t * retlen, u_char * buf)
+{
+	int i, col, page, chipnr;
+	struct nand_chip *this = mtd->priv;
+	int	blockcheck = (1 << (this->phys_erase_shift - this->page_shift)) - 1;
+
+	DEBUG (MTD_DEBUG_LEVEL3, "nand_read_oob: from = 0x%08x, len = %i\n", (unsigned int) from, (int) len);
+
+	/* Shift to get page */
+	page = (int)(from >> this->page_shift);
+	chipnr = (int)(from >> this->chip_shift);
+	
+	/* Mask to get column */
+	col = from & (mtd->oobsize - 1);
+
+	/* Initialize return length value */
+	*retlen = 0;
+
+	/* Do not allow reads past end of device */
+	if ((from + len) > mtd->size) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_read_oob: Attempt read beyond end of device\n");
+		*retlen = 0;
+		return -EINVAL;
+	}
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd , FL_READING);
+
+	/* Select the NAND device */
+	this->select_chip(mtd, chipnr);
+
+	/* Send the read command */
+	this->cmdfunc (mtd, NAND_CMD_READOOB, col, page & this->pagemask);
+	/* 
+	 * Read the data, if we read more than one page
+	 * oob data, let the device transfer the data !
+	 */
+	i = 0;
+	while (i < len) {
+		int thislen = mtd->oobsize - col;
+		thislen = min_t(int, thislen, len);
+		this->read_buf(mtd, &buf[i], thislen);
+		i += thislen;
+		
+		/* Apply delay or wait for ready/busy pin 
+		 * Do this before the AUTOINCR check, so no problems
+		 * arise if a chip which does auto increment
+		 * is marked as NOAUTOINCR by the board driver.
+		*/
+		if (!this->dev_ready) 
+			udelay (this->chip_delay);
+		else
+			while (!this->dev_ready(mtd));	
+
+		/* Read more ? */
+		if (i < len) {
+			page++;
+			col = 0;
+
+			/* Check, if we cross a chip boundary */
+			if (!(page & this->pagemask)) {
+				chipnr++;
+				this->select_chip(mtd, -1);
+				this->select_chip(mtd, chipnr);
+			}
+				
+			/* Check, if the chip supports auto page increment 
+			 * or if we have hit a block boundary. 
+			*/ 
+			if (!NAND_CANAUTOINCR(this) || !(page & blockcheck)) {
+				/* For subsequent page reads set offset to 0 */
+			        this->cmdfunc (mtd, NAND_CMD_READOOB, 0x0, page & this->pagemask);
+			}
+		}
+	}
+
+	/* Deselect and wake up anyone waiting on the device */
+	nand_release_device(mtd);
+
+	/* Return happy */
+	*retlen = len;
+	return 0;
+}
+
+/**
+ * nand_read_raw - [GENERIC] Read raw data including oob into buffer
+ * @mtd:	MTD device structure
+ * @buf:	temporary buffer
+ * @from:	offset to read from
+ * @len:	number of bytes to read
+ * @ooblen:	number of oob data bytes to read
+ *
+ * Read raw data including oob into buffer
+ */
+int nand_read_raw (struct mtd_info *mtd, uint8_t *buf, loff_t from, size_t len, size_t ooblen)
+{
+	struct nand_chip *this = mtd->priv;
+	int page = (int) (from >> this->page_shift);
+	int chip = (int) (from >> this->chip_shift);
+	int sndcmd = 1;
+	int cnt = 0;
+	int pagesize = mtd->oobblock + mtd->oobsize;
+	int	blockcheck = (1 << (this->phys_erase_shift - this->page_shift)) - 1;
+
+	/* Do not allow reads past end of device */
+	if ((from + len) > mtd->size) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_read_raw: Attempt read beyond end of device\n");
+		return -EINVAL;
+	}
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd , FL_READING);
+
+	this->select_chip (mtd, chip);
+	
+	/* Add requested oob length */
+	len += ooblen;
+	
+	while (len) {
+		if (sndcmd)
+			this->cmdfunc (mtd, NAND_CMD_READ0, 0, page & this->pagemask);
+		sndcmd = 0;	
+
+		this->read_buf (mtd, &buf[cnt], pagesize);
+
+		len -= pagesize;
+		cnt += pagesize;
+		page++;
+		
+		if (!this->dev_ready) 
+			udelay (this->chip_delay);
+		else
+			while (!this->dev_ready(mtd));	
+			
+		/* Check, if the chip supports auto page increment */ 
+		if (!NAND_CANAUTOINCR(this) || !(page & blockcheck))
+			sndcmd = 1;
+	}
+
+	/* Deselect and wake up anyone waiting on the device */
+	nand_release_device(mtd);
+	return 0;
+}
+
+
+/** 
+ * nand_prepare_oobbuf - [GENERIC] Prepare the out of band buffer 
+ * @mtd:	MTD device structure
+ * @fsbuf:	buffer given by fs driver
+ * @oobsel:	out of band selection structre
+ * @autoplace:	1 = place given buffer into the oob bytes
+ * @numpages:	number of pages to prepare
+ *
+ * Return:
+ * 1. Filesystem buffer available and autoplacement is off,
+ *    return filesystem buffer
+ * 2. No filesystem buffer or autoplace is off, return internal
+ *    buffer
+ * 3. Filesystem buffer is given and autoplace selected
+ *    put data from fs buffer into internal buffer and
+ *    retrun internal buffer
+ *
+ * Note: The internal buffer is filled with 0xff. This must
+ * be done only once, when no autoplacement happens
+ * Autoplacement sets the buffer dirty flag, which
+ * forces the 0xff fill before using the buffer again.
+ *
+*/
+static u_char * nand_prepare_oobbuf (struct mtd_info *mtd, u_char *fsbuf, struct nand_oobinfo *oobsel,
+		int autoplace, int numpages)
+{
+	struct nand_chip *this = mtd->priv;
+	int i, len, ofs;
+
+	/* Zero copy fs supplied buffer */
+	if (fsbuf && !autoplace) 
+		return fsbuf;
+
+	/* Check, if the buffer must be filled with ff again */
+	if (this->oobdirty) {	
+		memset (this->oob_buf, 0xff, 
+			mtd->oobsize << (this->phys_erase_shift - this->page_shift));
+		this->oobdirty = 0;
+	}	
+	
+	/* If we have no autoplacement or no fs buffer use the internal one */
+	if (!autoplace || !fsbuf)
+		return this->oob_buf;
+	
+	/* Walk through the pages and place the data */
+	this->oobdirty = 1;
+	ofs = 0;
+	while (numpages--) {
+		for (i = 0, len = 0; len < mtd->oobavail; i++) {
+			int to = ofs + oobsel->oobfree[i][0];
+			int num = oobsel->oobfree[i][1];
+			memcpy (&this->oob_buf[to], fsbuf, num);
+			len += num;
+			fsbuf += num;
+		}
+		ofs += mtd->oobavail;
+	}
+	return this->oob_buf;
+}
+
+#define NOTALIGNED(x) (x & (mtd->oobblock-1)) != 0
+
+/**
+ * nand_write - [MTD Interface] compability function for nand_write_ecc
+ * @mtd:	MTD device structure
+ * @to:		offset to write to
+ * @len:	number of bytes to write
+ * @retlen:	pointer to variable to store the number of written bytes
+ * @buf:	the data to write
+ *
+ * This function simply calls nand_write_ecc with oob buffer and oobsel = NULL
+ *
+*/
+static int nand_write (struct mtd_info *mtd, loff_t to, size_t len, size_t * retlen, const u_char * buf)
+{
+	return (nand_write_ecc (mtd, to, len, retlen, buf, NULL, NULL));
+}
+			   
+/**
+ * nand_write_ecc - [MTD Interface] NAND write with ECC
+ * @mtd:	MTD device structure
+ * @to:		offset to write to
+ * @len:	number of bytes to write
+ * @retlen:	pointer to variable to store the number of written bytes
+ * @buf:	the data to write
+ * @eccbuf:	filesystem supplied oob data buffer
+ * @oobsel:	oob selection structure
+ *
+ * NAND write with ECC
+ */
+static int nand_write_ecc (struct mtd_info *mtd, loff_t to, size_t len,
+			   size_t * retlen, const u_char * buf, u_char * eccbuf, struct nand_oobinfo *oobsel)
+{
+	int startpage, page, ret = -EIO, oob = 0, written = 0, chipnr;
+	int autoplace = 0, numpages, totalpages;
+	struct nand_chip *this = mtd->priv;
+	u_char *oobbuf, *bufstart;
+	int	ppblock = (1 << (this->phys_erase_shift - this->page_shift));
+
+	DEBUG (MTD_DEBUG_LEVEL3, "nand_write_ecc: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);
+
+	/* Initialize retlen, in case of early exit */
+	*retlen = 0;
+
+	/* Do not allow write past end of device */
+	if ((to + len) > mtd->size) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: Attempt to write past end of page\n");
+		return -EINVAL;
+	}
+
+	/* reject writes, which are not page aligned */	
+	if (NOTALIGNED (to) || NOTALIGNED(len)) {
+		printk (KERN_NOTICE "nand_write_ecc: Attempt to write not page aligned data\n");
+		return -EINVAL;
+	}
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd, FL_WRITING);
+
+	/* Calculate chipnr */
+	chipnr = (int)(to >> this->chip_shift);
+	/* Select the NAND device */
+	this->select_chip(mtd, chipnr);
+
+	/* Check, if it is write protected */
+	if (nand_check_wp(mtd))
+		goto out;
+
+	/* if oobsel is NULL, use chip defaults */
+	if (oobsel == NULL) 
+		oobsel = &mtd->oobinfo;		
+		
+	/* Autoplace of oob data ? Use the default placement scheme */
+	if (oobsel->useecc == MTD_NANDECC_AUTOPLACE) {
+		oobsel = this->autooob;
+		autoplace = 1;
+	}	
+	if (oobsel->useecc == MTD_NANDECC_AUTOPL_USR)
+		autoplace = 1;
+
+	/* Setup variables and oob buffer */
+	totalpages = len >> this->page_shift;
+	page = (int) (to >> this->page_shift);
+	/* Invalidate the page cache, if we write to the cached page */
+	if (page <= this->pagebuf && this->pagebuf < (page + totalpages))  
+		this->pagebuf = -1;
+	
+	/* Set it relative to chip */
+	page &= this->pagemask;
+	startpage = page;
+	/* Calc number of pages we can write in one go */
+	numpages = min (ppblock - (startpage  & (ppblock - 1)), totalpages);
+	oobbuf = nand_prepare_oobbuf (mtd, eccbuf, oobsel, autoplace, numpages);
+	bufstart = (u_char *)buf;
+
+	/* Loop until all data is written */
+	while (written < len) {
+
+		this->data_poi = (u_char*) &buf[written];
+		/* Write one page. If this is the last page to write
+		 * or the last page in this block, then use the
+		 * real pageprogram command, else select cached programming
+		 * if supported by the chip.
+		 */
+		ret = nand_write_page (mtd, this, page, &oobbuf[oob], oobsel, (--numpages > 0));
+		if (ret) {
+			DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: write_page failed %d\n", ret);
+			goto out;
+		}	
+		/* Next oob page */
+		oob += mtd->oobsize;
+		/* Update written bytes count */
+		written += mtd->oobblock;
+		if (written == len) 
+			goto cmp;
+		
+		/* Increment page address */
+		page++;
+
+		/* Have we hit a block boundary ? Then we have to verify and
+		 * if verify is ok, we have to setup the oob buffer for
+		 * the next pages.
+		*/
+		if (!(page & (ppblock - 1))){
+			int ofs;
+			this->data_poi = bufstart;
+			ret = nand_verify_pages (mtd, this, startpage, 
+				page - startpage,
+				oobbuf, oobsel, chipnr, (eccbuf != NULL));
+			if (ret) {
+				DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: verify_pages failed %d\n", ret);
+				goto out;
+			}	
+			*retlen = written;
+
+			ofs = autoplace ? mtd->oobavail : mtd->oobsize;
+			if (eccbuf)
+				eccbuf += (page - startpage) * ofs;
+			totalpages -= page - startpage;
+			numpages = min (totalpages, ppblock);
+			page &= this->pagemask;
+			startpage = page;
+			oobbuf = nand_prepare_oobbuf (mtd, eccbuf, oobsel, 
+					autoplace, numpages);
+			/* Check, if we cross a chip boundary */
+			if (!page) {
+				chipnr++;
+				this->select_chip(mtd, -1);
+				this->select_chip(mtd, chipnr);
+			}
+		}
+	}
+	/* Verify the remaining pages */
+cmp:
+	this->data_poi = bufstart;
+ 	ret = nand_verify_pages (mtd, this, startpage, totalpages,
+		oobbuf, oobsel, chipnr, (eccbuf != NULL));
+	if (!ret)
+		*retlen = written;
+	else	
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_write_ecc: verify_pages failed %d\n", ret);
+
+out:
+	/* Deselect and wake up anyone waiting on the device */
+	nand_release_device(mtd);
+
+	return ret;
+}
+
+
+/**
+ * nand_write_oob - [MTD Interface] NAND write out-of-band
+ * @mtd:	MTD device structure
+ * @to:		offset to write to
+ * @len:	number of bytes to write
+ * @retlen:	pointer to variable to store the number of written bytes
+ * @buf:	the data to write
+ *
+ * NAND write out-of-band
+ */
+static int nand_write_oob (struct mtd_info *mtd, loff_t to, size_t len, size_t * retlen, const u_char * buf)
+{
+	int column, page, status, ret = -EIO, chipnr;
+	struct nand_chip *this = mtd->priv;
+
+	DEBUG (MTD_DEBUG_LEVEL3, "nand_write_oob: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);
+
+	/* Shift to get page */
+	page = (int) (to >> this->page_shift);
+	chipnr = (int) (to >> this->chip_shift);
+
+	/* Mask to get column */
+	column = to & (mtd->oobsize - 1);
+
+	/* Initialize return length value */
+	*retlen = 0;
+
+	/* Do not allow write past end of page */
+	if ((column + len) > mtd->oobsize) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_write_oob: Attempt to write past end of page\n");
+		return -EINVAL;
+	}
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd, FL_WRITING);
+
+	/* Select the NAND device */
+	this->select_chip(mtd, chipnr);
+
+	/* Reset the chip. Some chips (like the Toshiba TC5832DC found
+	   in one of my DiskOnChip 2000 test units) will clear the whole
+	   data page too if we don't do this. I have no clue why, but
+	   I seem to have 'fixed' it in the doc2000 driver in
+	   August 1999.  dwmw2. */
+	this->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
+
+	/* Check, if it is write protected */
+	if (nand_check_wp(mtd))
+		goto out;
+	
+	/* Invalidate the page cache, if we write to the cached page */
+	if (page == this->pagebuf)
+		this->pagebuf = -1;
+
+	if (NAND_MUST_PAD(this)) {
+		/* Write out desired data */
+		this->cmdfunc (mtd, NAND_CMD_SEQIN, mtd->oobblock, page & this->pagemask);
+		/* prepad 0xff for partial programming */
+		this->write_buf(mtd, ffchars, column);
+		/* write data */
+		this->write_buf(mtd, buf, len);
+		/* postpad 0xff for partial programming */
+		this->write_buf(mtd, ffchars, mtd->oobsize - (len+column));
+	} else {
+		/* Write out desired data */
+		this->cmdfunc (mtd, NAND_CMD_SEQIN, mtd->oobblock + column, page & this->pagemask);
+		/* write data */
+		this->write_buf(mtd, buf, len);
+	}
+	/* Send command to program the OOB data */
+	this->cmdfunc (mtd, NAND_CMD_PAGEPROG, -1, -1);
+
+	status = this->waitfunc (mtd, this, FL_WRITING);
+
+	/* See if device thinks it succeeded */
+	if (status & 0x01) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_write_oob: " "Failed write, page 0x%08x\n", page);
+		ret = -EIO;
+		goto out;
+	}
+	/* Return happy */
+	*retlen = len;
+
+#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
+	/* Send command to read back the data */
+	this->cmdfunc (mtd, NAND_CMD_READOOB, column, page & this->pagemask);
+
+	if (this->verify_buf(mtd, buf, len)) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_write_oob: " "Failed write verify, page 0x%08x\n", page);
+		ret = -EIO;
+		goto out;
+	}
+#endif
+	ret = 0;
+out:
+	/* Deselect and wake up anyone waiting on the device */
+	nand_release_device(mtd);
+
+	return ret;
+}
+
+/* XXX U-BOOT XXX */
+#if 0
+/**
+ * nand_writev - [MTD Interface] compabilty function for nand_writev_ecc
+ * @mtd:	MTD device structure
+ * @vecs:	the iovectors to write
+ * @count:	number of vectors
+ * @to:		offset to write to
+ * @retlen:	pointer to variable to store the number of written bytes
+ *
+ * NAND write with kvec. This just calls the ecc function
+ */
+static int nand_writev (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, 
+		loff_t to, size_t * retlen)
+{
+	return (nand_writev_ecc (mtd, vecs, count, to, retlen, NULL, NULL));	
+}
+
+/**
+ * nand_writev_ecc - [MTD Interface] write with iovec with ecc
+ * @mtd:	MTD device structure
+ * @vecs:	the iovectors to write
+ * @count:	number of vectors
+ * @to:		offset to write to
+ * @retlen:	pointer to variable to store the number of written bytes
+ * @eccbuf:	filesystem supplied oob data buffer
+ * @oobsel:	oob selection structure
+ *
+ * NAND write with iovec with ecc
+ */
+static int nand_writev_ecc (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, 
+		loff_t to, size_t * retlen, u_char *eccbuf, struct nand_oobinfo *oobsel)
+{
+	int i, page, len, total_len, ret = -EIO, written = 0, chipnr;
+	int oob, numpages, autoplace = 0, startpage;
+	struct nand_chip *this = mtd->priv;
+	int	ppblock = (1 << (this->phys_erase_shift - this->page_shift));
+	u_char *oobbuf, *bufstart;
+
+	/* Preset written len for early exit */
+	*retlen = 0;
+
+	/* Calculate total length of data */
+	total_len = 0;
+	for (i = 0; i < count; i++)
+		total_len += (int) vecs[i].iov_len;
+
+	DEBUG (MTD_DEBUG_LEVEL3,
+	       "nand_writev: to = 0x%08x, len = %i, count = %ld\n", (unsigned int) to, (unsigned int) total_len, count);
+
+	/* Do not allow write past end of page */
+	if ((to + total_len) > mtd->size) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_writev: Attempted write past end of device\n");
+		return -EINVAL;
+	}
+
+	/* reject writes, which are not page aligned */	
+	if (NOTALIGNED (to) || NOTALIGNED(total_len)) {
+		printk (KERN_NOTICE "nand_write_ecc: Attempt to write not page aligned data\n");
+		return -EINVAL;
+	}
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd, FL_WRITING);
+
+	/* Get the current chip-nr */
+	chipnr = (int) (to >> this->chip_shift);
+	/* Select the NAND device */
+	this->select_chip(mtd, chipnr);
+
+	/* Check, if it is write protected */
+	if (nand_check_wp(mtd))
+		goto out;
+
+	/* if oobsel is NULL, use chip defaults */
+	if (oobsel == NULL) 
+		oobsel = &mtd->oobinfo;		
+
+	/* Autoplace of oob data ? Use the default placement scheme */
+	if (oobsel->useecc == MTD_NANDECC_AUTOPLACE) {
+		oobsel = this->autooob;
+		autoplace = 1;
+	}	
+	if (oobsel->useecc == MTD_NANDECC_AUTOPL_USR)
+		autoplace = 1;
+
+	/* Setup start page */
+	page = (int) (to >> this->page_shift);
+	/* Invalidate the page cache, if we write to the cached page */
+	if (page <= this->pagebuf && this->pagebuf < ((to + total_len) >> this->page_shift))  
+		this->pagebuf = -1;
+
+	startpage = page & this->pagemask;
+
+	/* Loop until all kvec' data has been written */
+	len = 0;
+	while (count) {
+		/* If the given tuple is >= pagesize then
+		 * write it out from the iov
+		 */
+		if ((vecs->iov_len - len) >= mtd->oobblock) {
+			/* Calc number of pages we can write
+			 * out of this iov in one go */
+			numpages = (vecs->iov_len - len) >> this->page_shift;
+			/* Do not cross block boundaries */
+			numpages = min (ppblock - (startpage & (ppblock - 1)), numpages);
+			oobbuf = nand_prepare_oobbuf (mtd, NULL, oobsel, autoplace, numpages);
+			bufstart = (u_char *)vecs->iov_base;
+			bufstart += len;
+			this->data_poi = bufstart;
+			oob = 0;
+			for (i = 1; i <= numpages; i++) {
+				/* Write one page. If this is the last page to write
+				 * then use the real pageprogram command, else select 
+				 * cached programming if supported by the chip.
+				 */
+				ret = nand_write_page (mtd, this, page & this->pagemask, 
+					&oobbuf[oob], oobsel, i != numpages);
+				if (ret)
+					goto out;
+				this->data_poi += mtd->oobblock;
+				len += mtd->oobblock;
+				oob += mtd->oobsize;
+				page++;
+			}
+			/* Check, if we have to switch to the next tuple */
+			if (len >= (int) vecs->iov_len) {
+				vecs++;
+				len = 0;
+				count--;
+			}
+		} else {
+			/* We must use the internal buffer, read data out of each 
+			 * tuple until we have a full page to write
+			 */
+			int cnt = 0;
+			while (cnt < mtd->oobblock) {
+				if (vecs->iov_base != NULL && vecs->iov_len) 
+					this->data_buf[cnt++] = ((u_char *) vecs->iov_base)[len++];
+				/* Check, if we have to switch to the next tuple */
+				if (len >= (int) vecs->iov_len) {
+					vecs++;
+					len = 0;
+					count--;
+				}
+			}
+			this->pagebuf = page;	
+			this->data_poi = this->data_buf;	
+			bufstart = this->data_poi;
+			numpages = 1;		
+			oobbuf = nand_prepare_oobbuf (mtd, NULL, oobsel, autoplace, numpages);
+			ret = nand_write_page (mtd, this, page & this->pagemask,
+				oobbuf, oobsel, 0);
+			if (ret)
+				goto out;
+			page++;
+		}
+
+		this->data_poi = bufstart;
+		ret = nand_verify_pages (mtd, this, startpage, numpages, oobbuf, oobsel, chipnr, 0);
+		if (ret)
+			goto out;
+			
+		written += mtd->oobblock * numpages;
+		/* All done ? */
+		if (!count)
+			break;
+
+		startpage = page & this->pagemask;
+		/* Check, if we cross a chip boundary */
+		if (!startpage) {
+			chipnr++;
+			this->select_chip(mtd, -1);
+			this->select_chip(mtd, chipnr);
+		}
+	}
+	ret = 0;
+out:
+	/* Deselect and wake up anyone waiting on the device */
+	nand_release_device(mtd);
+
+	*retlen = written;
+	return ret;
+}
+#endif
+
+/**
+ * single_erease_cmd - [GENERIC] NAND standard block erase command function
+ * @mtd:	MTD device structure
+ * @page:	the page address of the block which will be erased
+ *
+ * Standard erase command for NAND chips
+ */
+static void single_erase_cmd (struct mtd_info *mtd, int page)
+{
+	struct nand_chip *this = mtd->priv;
+	/* Send commands to erase a block */
+	this->cmdfunc (mtd, NAND_CMD_ERASE1, -1, page);
+	this->cmdfunc (mtd, NAND_CMD_ERASE2, -1, -1);
+}
+
+/**
+ * multi_erease_cmd - [GENERIC] AND specific block erase command function
+ * @mtd:	MTD device structure
+ * @page:	the page address of the block which will be erased
+ *
+ * AND multi block erase command function
+ * Erase 4 consecutive blocks
+ */
+static void multi_erase_cmd (struct mtd_info *mtd, int page)
+{
+	struct nand_chip *this = mtd->priv;
+	/* Send commands to erase a block */
+	this->cmdfunc (mtd, NAND_CMD_ERASE1, -1, page++);
+	this->cmdfunc (mtd, NAND_CMD_ERASE1, -1, page++);
+	this->cmdfunc (mtd, NAND_CMD_ERASE1, -1, page++);
+	this->cmdfunc (mtd, NAND_CMD_ERASE1, -1, page);
+	this->cmdfunc (mtd, NAND_CMD_ERASE2, -1, -1);
+}
+
+/**
+ * nand_erase - [MTD Interface] erase block(s)
+ * @mtd:	MTD device structure
+ * @instr:	erase instruction
+ *
+ * Erase one ore more blocks
+ */
+static int nand_erase (struct mtd_info *mtd, struct erase_info *instr)
+{
+	return nand_erase_nand (mtd, instr, 0);
+}
+ 
+/**
+ * nand_erase_intern - [NAND Interface] erase block(s)
+ * @mtd:	MTD device structure
+ * @instr:	erase instruction
+ * @allowbbt:	allow erasing the bbt area
+ *
+ * Erase one ore more blocks
+ */
+int nand_erase_nand (struct mtd_info *mtd, struct erase_info *instr, int allowbbt)
+{
+	int page, len, status, pages_per_block, ret, chipnr;
+	struct nand_chip *this = mtd->priv;
+
+	DEBUG (MTD_DEBUG_LEVEL3,
+	       "nand_erase: start = 0x%08x, len = %i\n", (unsigned int) instr->addr, (unsigned int) instr->len);
+
+	/* Start address must align on block boundary */
+	if (instr->addr & ((1 << this->phys_erase_shift) - 1)) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_erase: Unaligned address\n");
+		return -EINVAL;
+	}
+
+	/* Length must align on block boundary */
+	if (instr->len & ((1 << this->phys_erase_shift) - 1)) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_erase: Length not block aligned\n");
+		return -EINVAL;
+	}
+
+	/* Do not allow erase past end of device */
+	if ((instr->len + instr->addr) > mtd->size) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_erase: Erase past end of device\n");
+		return -EINVAL;
+	}
+
+	instr->fail_addr = 0xffffffff;
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd, FL_ERASING);
+
+	/* Shift to get first page */
+	page = (int) (instr->addr >> this->page_shift);
+	chipnr = (int) (instr->addr >> this->chip_shift);
+
+	/* Calculate pages in each block */
+	pages_per_block = 1 << (this->phys_erase_shift - this->page_shift);
+
+	/* Select the NAND device */
+	this->select_chip(mtd, chipnr);
+
+	/* Check the WP bit */
+	/* Check, if it is write protected */
+	if (nand_check_wp(mtd)) {
+		DEBUG (MTD_DEBUG_LEVEL0, "nand_erase: Device is write protected!!!\n");
+		instr->state = MTD_ERASE_FAILED;
+		goto erase_exit;
+	}
+
+	/* Loop through the pages */
+	len = instr->len;
+
+	instr->state = MTD_ERASING;
+
+	while (len) {
+		/* Check if we have a bad block, we do not erase bad blocks ! */
+		if (nand_block_checkbad(mtd, ((loff_t) page) << this->page_shift, 0, allowbbt)) {
+			printk (KERN_WARNING "nand_erase: attempt to erase a bad block at page 0x%08x\n", page);
+			instr->state = MTD_ERASE_FAILED;
+			goto erase_exit;
+		}
+		
+		/* Invalidate the page cache, if we erase the block which contains 
+		   the current cached page */
+		if (page <= this->pagebuf && this->pagebuf < (page + pages_per_block))
+			this->pagebuf = -1;
+
+		this->erase_cmd (mtd, page & this->pagemask);
+		
+		status = this->waitfunc (mtd, this, FL_ERASING);
+
+		/* See if block erase succeeded */
+		if (status & 0x01) {
+			DEBUG (MTD_DEBUG_LEVEL0, "nand_erase: " "Failed erase, page 0x%08x\n", page);
+			instr->state = MTD_ERASE_FAILED;
+			instr->fail_addr = (page << this->page_shift);
+			goto erase_exit;
+		}
+		
+		/* Increment page address and decrement length */
+		len -= (1 << this->phys_erase_shift);
+		page += pages_per_block;
+
+		/* Check, if we cross a chip boundary */
+		if (len && !(page & this->pagemask)) {
+			chipnr++;
+			this->select_chip(mtd, -1);
+			this->select_chip(mtd, chipnr);
+		}
+	}
+	instr->state = MTD_ERASE_DONE;
+
+erase_exit:
+
+	ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
+	/* Do call back function */
+	if (!ret)
+		mtd_erase_callback(instr);
+
+	/* Deselect and wake up anyone waiting on the device */
+	nand_release_device(mtd);
+
+	/* Return more or less happy */
+	return ret;
+}
+
+/**
+ * nand_sync - [MTD Interface] sync
+ * @mtd:	MTD device structure
+ *
+ * Sync is actually a wait for chip ready function
+ */
+static void nand_sync (struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+
+	DEBUG (MTD_DEBUG_LEVEL3, "nand_sync: called\n");
+
+	/* Grab the lock and see if the device is available */
+	nand_get_device (this, mtd, FL_SYNCING);
+	/* Release it and go back */
+	nand_release_device (mtd);
+}
+
+
+/**
+ * nand_block_isbad - [MTD Interface] Check whether the block at the given offset is bad
+ * @mtd:	MTD device structure
+ * @ofs:	offset relative to mtd start
+ */
+static int nand_block_isbad (struct mtd_info *mtd, loff_t ofs)
+{
+	/* Check for invalid offset */
+	if (ofs > mtd->size) 
+		return -EINVAL;
+	
+	return nand_block_checkbad (mtd, ofs, 1, 0);
+}
+
+/**
+ * nand_block_markbad - [MTD Interface] Mark the block at the given offset as bad
+ * @mtd:	MTD device structure
+ * @ofs:	offset relative to mtd start
+ */
+static int nand_block_markbad (struct mtd_info *mtd, loff_t ofs)
+{
+	struct nand_chip *this = mtd->priv;
+	int ret;
+
+        if ((ret = nand_block_isbad(mtd, ofs))) {
+        	/* If it was bad already, return success and do nothing. */
+		if (ret > 0)
+			return 0;
+        	return ret;
+        }
+
+	return this->block_markbad(mtd, ofs);
+}
+
+/**
+ * nand_scan - [NAND Interface] Scan for the NAND device
+ * @mtd:	MTD device structure
+ * @maxchips:	Number of chips to scan for
+ *
+ * This fills out all the not initialized function pointers
+ * with the defaults.
+ * The flash ID is read and the mtd/chip structures are
+ * filled with the appropriate values. Buffers are allocated if
+ * they are not provided by the board driver
+ *
+ */
+int nand_scan (struct mtd_info *mtd, int maxchips)
+{
+	int i, j, nand_maf_id, nand_dev_id, busw;
+	struct nand_chip *this = mtd->priv;
+
+	/* Get buswidth to select the correct functions*/
+	busw = this->options & NAND_BUSWIDTH_16;
+
+	/* check for proper chip_delay setup, set 20us if not */
+	if (!this->chip_delay)
+		this->chip_delay = 20;
+
+	/* check, if a user supplied command function given */
+	if (this->cmdfunc == NULL)
+		this->cmdfunc = nand_command;
+
+	/* check, if a user supplied wait function given */
+	if (this->waitfunc == NULL)
+		this->waitfunc = nand_wait;
+
+	if (!this->select_chip)
+		this->select_chip = nand_select_chip;
+	if (!this->write_byte)
+		this->write_byte = busw ? nand_write_byte16 : nand_write_byte;
+	if (!this->read_byte)
+		this->read_byte = busw ? nand_read_byte16 : nand_read_byte;
+	if (!this->write_word)
+		this->write_word = nand_write_word;
+	if (!this->read_word)
+		this->read_word = nand_read_word;
+	if (!this->block_bad)
+		this->block_bad = nand_block_bad;
+	if (!this->block_markbad)
+		this->block_markbad = nand_default_block_markbad;
+	if (!this->write_buf)
+		this->write_buf = busw ? nand_write_buf16 : nand_write_buf;
+	if (!this->read_buf)
+		this->read_buf = busw ? nand_read_buf16 : nand_read_buf;
+	if (!this->verify_buf)
+		this->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf;
+	if (!this->scan_bbt)
+		this->scan_bbt = nand_default_bbt;
+
+	/* Select the device */
+	this->select_chip(mtd, 0);
+
+	/* Send the command for reading device ID */
+	this->cmdfunc (mtd, NAND_CMD_READID, 0x00, -1);
+
+	/* Read manufacturer and device IDs */
+	nand_maf_id = this->read_byte(mtd);
+	nand_dev_id = this->read_byte(mtd);
+
+	/* Print and store flash device information */
+	for (i = 0; nand_flash_ids[i].name != NULL; i++) {
+				
+		if (nand_dev_id != nand_flash_ids[i].id) 
+			continue;
+
+		if (!mtd->name) mtd->name = nand_flash_ids[i].name;
+		this->chipsize = nand_flash_ids[i].chipsize << 20;
+		
+		/* New devices have all the information in additional id bytes */
+		if (!nand_flash_ids[i].pagesize) {
+			int extid;
+			/* The 3rd id byte contains non relevant data ATM */
+			extid = this->read_byte(mtd);
+			/* The 4th id byte is the important one */
+			extid = this->read_byte(mtd);
+			/* Calc pagesize */
+			mtd->oobblock = 1024 << (extid & 0x3);
+			extid >>= 2;
+			/* Calc oobsize */
+			mtd->oobsize = (8 << (extid & 0x03)) * (mtd->oobblock / 512);
+			extid >>= 2;
+			/* Calc blocksize. Blocksize is multiples of 64KiB */
+			mtd->erasesize = (64 * 1024)  << (extid & 0x03);
+			extid >>= 2;
+			/* Get buswidth information */
+			busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
+		
+		} else {
+			/* Old devices have this data hardcoded in the
+			 * device id table */
+			mtd->erasesize = nand_flash_ids[i].erasesize;
+			mtd->oobblock = nand_flash_ids[i].pagesize;
+			mtd->oobsize = mtd->oobblock / 32;
+			busw = nand_flash_ids[i].options & NAND_BUSWIDTH_16;
+		}
+
+		/* Check, if buswidth is correct. Hardware drivers should set
+		 * this correct ! */
+		if (busw != (this->options & NAND_BUSWIDTH_16)) {
+			printk (KERN_INFO "NAND device: Manufacturer ID:"
+				" 0x%02x, Chip ID: 0x%02x (%s %s)\n", nand_maf_id, nand_dev_id, 
+				nand_manuf_ids[i].name , mtd->name);
+			printk (KERN_WARNING 
+				"NAND bus width %d instead %d bit\n", 
+					(this->options & NAND_BUSWIDTH_16) ? 16 : 8,
+					busw ? 16 : 8);
+			this->select_chip(mtd, -1);
+			return 1;	
+		}
+		
+		/* Calculate the address shift from the page size */	
+		this->page_shift = ffs(mtd->oobblock) - 1;
+		this->bbt_erase_shift = this->phys_erase_shift = ffs(mtd->erasesize) - 1;
+		this->chip_shift = ffs(this->chipsize) - 1;
+
+		/* Set the bad block position */
+		this->badblockpos = mtd->oobblock > 512 ? 
+			NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS;
+
+		/* Get chip options, preserve non chip based options */
+		this->options &= ~NAND_CHIPOPTIONS_MSK;
+		this->options |= nand_flash_ids[i].options & NAND_CHIPOPTIONS_MSK;
+		/* Set this as a default. Board drivers can override it, if neccecary */
+		this->options |= NAND_NO_AUTOINCR;
+		/* Check if this is a not a samsung device. Do not clear the options
+		 * for chips which are not having an extended id.
+		 */	
+		if (nand_maf_id != NAND_MFR_SAMSUNG && !nand_flash_ids[i].pagesize)
+			this->options &= ~NAND_SAMSUNG_LP_OPTIONS;
+		
+		/* Check for AND chips with 4 page planes */
+		if (this->options & NAND_4PAGE_ARRAY)
+			this->erase_cmd = multi_erase_cmd;
+		else
+			this->erase_cmd = single_erase_cmd;
+
+		/* Do not replace user supplied command function ! */
+		if (mtd->oobblock > 512 && this->cmdfunc == nand_command)
+			this->cmdfunc = nand_command_lp;
+				
+		/* Try to identify manufacturer */
+		for (j = 0; nand_manuf_ids[j].id != 0x0; j++) {
+			if (nand_manuf_ids[j].id == nand_maf_id)
+				break;
+		}
+		printk (KERN_INFO "NAND device: Manufacturer ID:"
+			" 0x%02x, Chip ID: 0x%02x (%s %s)\n", nand_maf_id, nand_dev_id, 
+			nand_manuf_ids[j].name , nand_flash_ids[i].name);
+		break;
+	}
+
+	if (!nand_flash_ids[i].name) {
+		printk (KERN_WARNING "No NAND device found!!!\n");
+		this->select_chip(mtd, -1);
+		return 1;
+	}
+
+	for (i=1; i < maxchips; i++) {
+		this->select_chip(mtd, i);
+
+		/* Send the command for reading device ID */
+		this->cmdfunc (mtd, NAND_CMD_READID, 0x00, -1);
+
+		/* Read manufacturer and device IDs */
+		if (nand_maf_id != this->read_byte(mtd) ||
+		    nand_dev_id != this->read_byte(mtd))
+			break;
+	}
+	if (i > 1)
+		printk(KERN_INFO "%d NAND chips detected\n", i);
+	
+	/* Allocate buffers, if neccecary */
+	if (!this->oob_buf) {
+		size_t len;
+		len = mtd->oobsize << (this->phys_erase_shift - this->page_shift);
+		this->oob_buf = kmalloc (len, GFP_KERNEL);
+		if (!this->oob_buf) {
+			printk (KERN_ERR "nand_scan(): Cannot allocate oob_buf\n");
+			return -ENOMEM;
+		}
+		this->options |= NAND_OOBBUF_ALLOC;
+	}
+	
+	if (!this->data_buf) {
+		size_t len;
+		len = mtd->oobblock + mtd->oobsize;
+		this->data_buf = kmalloc (len, GFP_KERNEL);
+		if (!this->data_buf) {
+			if (this->options & NAND_OOBBUF_ALLOC)
+				kfree (this->oob_buf);
+			printk (KERN_ERR "nand_scan(): Cannot allocate data_buf\n");
+			return -ENOMEM;
+		}
+		this->options |= NAND_DATABUF_ALLOC;
+	}
+
+	/* Store the number of chips and calc total size for mtd */
+	this->numchips = i;
+	mtd->size = i * this->chipsize;
+	/* Convert chipsize to number of pages per chip -1. */
+	this->pagemask = (this->chipsize >> this->page_shift) - 1;
+	/* Preset the internal oob buffer */
+	memset(this->oob_buf, 0xff, mtd->oobsize << (this->phys_erase_shift - this->page_shift));
+
+	/* If no default placement scheme is given, select an
+	 * appropriate one */
+	if (!this->autooob) {
+		/* Select the appropriate default oob placement scheme for
+		 * placement agnostic filesystems */
+		switch (mtd->oobsize) { 
+		case 8:
+			this->autooob = &nand_oob_8;
+			break;
+		case 16:
+			this->autooob = &nand_oob_16;
+			break;
+		case 64:
+			this->autooob = &nand_oob_64;
+			break;
+		default:
+			printk (KERN_WARNING "No oob scheme defined for oobsize %d\n",
+				mtd->oobsize);
+/*			BUG(); */
+		}
+	}
+	
+	/* The number of bytes available for the filesystem to place fs dependend
+	 * oob data */
+	if (this->options & NAND_BUSWIDTH_16) {
+		mtd->oobavail = mtd->oobsize - (this->autooob->eccbytes + 2);
+		if (this->autooob->eccbytes & 0x01)
+			mtd->oobavail--;
+	} else
+		mtd->oobavail = mtd->oobsize - (this->autooob->eccbytes + 1);
+
+	/* 
+	 * check ECC mode, default to software
+	 * if 3byte/512byte hardware ECC is selected and we have 256 byte pagesize
+	 * fallback to software ECC 
+	*/
+	this->eccsize = 256;	/* set default eccsize */	
+	this->eccbytes = 3;
+
+	switch (this->eccmode) {
+	case NAND_ECC_HW12_2048:
+		if (mtd->oobblock < 2048) {
+			printk(KERN_WARNING "2048 byte HW ECC not possible on %d byte page size, fallback to SW ECC\n",
+			       mtd->oobblock);
+			this->eccmode = NAND_ECC_SOFT;
+			this->calculate_ecc = nand_calculate_ecc;
+			this->correct_data = nand_correct_data;
+		} else
+			this->eccsize = 2048;
+		break;
+
+	case NAND_ECC_HW3_512: 
+	case NAND_ECC_HW6_512: 
+	case NAND_ECC_HW8_512: 
+		if (mtd->oobblock == 256) {
+			printk (KERN_WARNING "512 byte HW ECC not possible on 256 Byte pagesize, fallback to SW ECC \n");
+			this->eccmode = NAND_ECC_SOFT;
+			this->calculate_ecc = nand_calculate_ecc;
+			this->correct_data = nand_correct_data;
+		} else 
+			this->eccsize = 512; /* set eccsize to 512 */
+		break;
+			
+	case NAND_ECC_HW3_256:
+		break;
+		
+	case NAND_ECC_NONE: 
+		printk (KERN_WARNING "NAND_ECC_NONE selected by board driver. This is not recommended !!\n");
+		this->eccmode = NAND_ECC_NONE;
+		break;
+
+	case NAND_ECC_SOFT:	
+		this->calculate_ecc = nand_calculate_ecc;
+		this->correct_data = nand_correct_data;
+		break;
+
+	default:
+		printk (KERN_WARNING "Invalid NAND_ECC_MODE %d\n", this->eccmode);
+/*		BUG(); */
+	}	
+
+	/* Check hardware ecc function availability and adjust number of ecc bytes per 
+	 * calculation step
+	*/
+	switch (this->eccmode) {
+	case NAND_ECC_HW12_2048:
+		this->eccbytes += 4;
+	case NAND_ECC_HW8_512: 
+		this->eccbytes += 2;
+	case NAND_ECC_HW6_512: 
+		this->eccbytes += 3;
+	case NAND_ECC_HW3_512: 
+	case NAND_ECC_HW3_256:
+		if (this->calculate_ecc && this->correct_data && this->enable_hwecc)
+			break;
+		printk (KERN_WARNING "No ECC functions supplied, Hardware ECC not possible\n");
+/*		BUG();	*/
+	}
+		
+	mtd->eccsize = this->eccsize;
+	
+	/* Set the number of read / write steps for one page to ensure ECC generation */
+	switch (this->eccmode) {
+	case NAND_ECC_HW12_2048:
+		this->eccsteps = mtd->oobblock / 2048;
+		break;
+	case NAND_ECC_HW3_512:
+	case NAND_ECC_HW6_512:
+	case NAND_ECC_HW8_512:
+		this->eccsteps = mtd->oobblock / 512;
+		break;
+	case NAND_ECC_HW3_256:
+	case NAND_ECC_SOFT:	
+		this->eccsteps = mtd->oobblock / 256;
+		break;
+		
+	case NAND_ECC_NONE: 
+		this->eccsteps = 1;
+		break;
+	}
+
+/* XXX U-BOOT XXX */
+#if 0	
+	/* Initialize state, waitqueue and spinlock */
+	this->state = FL_READY;
+	init_waitqueue_head (&this->wq);
+	spin_lock_init (&this->chip_lock);
+#endif
+
+	/* De-select the device */
+	this->select_chip(mtd, -1);
+
+	/* Invalidate the pagebuffer reference */
+	this->pagebuf = -1;
+
+	/* Fill in remaining MTD driver data */
+	mtd->type = MTD_NANDFLASH;
+	mtd->flags = MTD_CAP_NANDFLASH | MTD_ECC;
+	mtd->ecctype = MTD_ECC_SW;
+	mtd->erase = nand_erase;
+	mtd->point = NULL;
+	mtd->unpoint = NULL;
+	mtd->read = nand_read;
+	mtd->write = nand_write;
+	mtd->read_ecc = nand_read_ecc;
+	mtd->write_ecc = nand_write_ecc;
+	mtd->read_oob = nand_read_oob;
+	mtd->write_oob = nand_write_oob;
+/* XXX U-BOOT XXX */
+#if 0
+	mtd->readv = NULL;
+	mtd->writev = nand_writev;
+	mtd->writev_ecc = nand_writev_ecc;
+#endif
+	mtd->sync = nand_sync;
+/* XXX U-BOOT XXX */
+#if 0
+	mtd->lock = NULL;
+	mtd->unlock = NULL;
+	mtd->suspend = NULL;
+	mtd->resume = NULL;
+#endif
+	mtd->block_isbad = nand_block_isbad;
+	mtd->block_markbad = nand_block_markbad;
+
+	/* and make the autooob the default one */
+	memcpy(&mtd->oobinfo, this->autooob, sizeof(mtd->oobinfo));
+/* XXX U-BOOT XXX */
+#if 0
+	mtd->owner = THIS_MODULE;
+#endif
+	/* Build bad block table */
+	return this->scan_bbt (mtd);
+}
+
+/**
+ * nand_release - [NAND Interface] Free resources held by the NAND device 
+ * @mtd:	MTD device structure
+*/
+void nand_release (struct mtd_info *mtd)
+{
+	struct nand_chip *this = mtd->priv;
+
+#ifdef CONFIG_MTD_PARTITIONS
+	/* Deregister partitions */
+	del_mtd_partitions (mtd);
+#endif
+	/* Deregister the device */
+/* XXX U-BOOT XXX */
+#if 0
+	del_mtd_device (mtd);
+#endif
+	/* Free bad block table memory, if allocated */
+	if (this->bbt)
+		kfree (this->bbt);
+	/* Buffer allocated by nand_scan ? */
+	if (this->options & NAND_OOBBUF_ALLOC)
+		kfree (this->oob_buf);
+	/* Buffer allocated by nand_scan ? */
+	if (this->options & NAND_DATABUF_ALLOC)
+		kfree (this->data_buf);
+}
+
+#endif