text: /*
   *  linux/drivers/mtd/onenand/onenand_base.c
   *
   *  Copyright © 2005-2009 Samsung Electronics
   *  Copyright © 2007 Nokia Corporation
   *
   *  Kyungmin Park <kyungmin.park@samsung.com>
   *
   *  Credits:
   *	Adrian Hunter <ext-adrian.hunter@nokia.com>:
   *	auto-placement support, read-while load support, various fixes
   *
   *	Vishak G <vishak.g at samsung.com>, Rohit Hagargundgi <h.rohit at samsung.com>
   *	Flex-OneNAND support
   *	Amul Kumar Saha <amul.saha at samsung.com>
   *	OTP support
   *
   * 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.
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/moduleparam.h>
  #include <linux/slab.h>
  #include <linux/init.h>
  #include <linux/sched.h>
  #include <linux/delay.h>
  #include <linux/interrupt.h>
  #include <linux/jiffies.h>
  #include <linux/mtd/mtd.h>
  #include <linux/mtd/onenand.h>
  #include <linux/mtd/partitions.h>
  
  #include <asm/io.h>
  
  /*
   * Multiblock erase if number of blocks to erase is 2 or more.
   * Maximum number of blocks for simultaneous erase is 64.
   */
  #define MB_ERASE_MIN_BLK_COUNT 2
  #define MB_ERASE_MAX_BLK_COUNT 64
  
  /* Default Flex-OneNAND boundary and lock respectively */
  static int flex_bdry[MAX_DIES * 2] = { -1, 0, -1, 0 };
  
  module_param_array(flex_bdry, int, NULL, 0400);
  MODULE_PARM_DESC(flex_bdry,	"SLC Boundary information for Flex-OneNAND"
  				"Syntax:flex_bdry=DIE_BDRY,LOCK,..."
  				"DIE_BDRY: SLC boundary of the die"
  				"LOCK: Locking information for SLC boundary"
  				"    : 0->Set boundary in unlocked status"
  				"    : 1->Set boundary in locked status");
  
  /* Default OneNAND/Flex-OneNAND OTP options*/
  static int otp;
  
  module_param(otp, int, 0400);
  MODULE_PARM_DESC(otp,	"Corresponding behaviour of OneNAND in OTP"
  			"Syntax : otp=LOCK_TYPE"
  			"LOCK_TYPE : Keys issued, for specific OTP Lock type"
  			"	   : 0 -> Default (No Blocks Locked)"
  			"	   : 1 -> OTP Block lock"
  			"	   : 2 -> 1st Block lock"
  			"	   : 3 -> BOTH OTP Block and 1st Block lock");
  
  /*
   * flexonenand_oob_128 - oob info for Flex-Onenand with 4KB page
   * For now, we expose only 64 out of 80 ecc bytes
   */
  static struct nand_ecclayout flexonenand_oob_128 = {
  	.eccbytes	= 64,
  	.eccpos		= {
  		6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
  		22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
  		38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
  		54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
  		70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
  		86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
  		102, 103, 104, 105
  		},
  	.oobfree	= {
  		{2, 4}, {18, 4}, {34, 4}, {50, 4},
  		{66, 4}, {82, 4}, {98, 4}, {114, 4}
  	}
  };
  
  /*
   * onenand_oob_128 - oob info for OneNAND with 4KB page
   *
   * Based on specification:
   * 4Gb M-die OneNAND Flash (KFM4G16Q4M, KFN8G16Q4M). Rev. 1.3, Apr. 2010
   *
   * For eccpos we expose only 64 bytes out of 72 (see struct nand_ecclayout)
   *
   * oobfree uses the spare area fields marked as
   * "Managed by internal ECC logic for Logical Sector Number area"
   */
  static struct nand_ecclayout onenand_oob_128 = {
  	.eccbytes	= 64,
  	.eccpos		= {
  		7, 8, 9, 10, 11, 12, 13, 14, 15,
  		23, 24, 25, 26, 27, 28, 29, 30, 31,
  		39, 40, 41, 42, 43, 44, 45, 46, 47,
  		55, 56, 57, 58, 59, 60, 61, 62, 63,
  		71, 72, 73, 74, 75, 76, 77, 78, 79,
  		87, 88, 89, 90, 91, 92, 93, 94, 95,
  		103, 104, 105, 106, 107, 108, 109, 110, 111,
  		119
  	},
  	.oobfree	= {
  		{2, 3}, {18, 3}, {34, 3}, {50, 3},
  		{66, 3}, {82, 3}, {98, 3}, {114, 3}
  	}
  };
  
  /**
   * onenand_oob_64 - oob info for large (2KB) page
   */
  static struct nand_ecclayout onenand_oob_64 = {
  	.eccbytes	= 20,
  	.eccpos		= {
  		8, 9, 10, 11, 12,
  		24, 25, 26, 27, 28,
  		40, 41, 42, 43, 44,
  		56, 57, 58, 59, 60,
  		},
  	.oobfree	= {
  		{2, 3}, {14, 2}, {18, 3}, {30, 2},
  		{34, 3}, {46, 2}, {50, 3}, {62, 2}
  	}
  };
  
  /**
   * onenand_oob_32 - oob info for middle (1KB) page
   */
  static struct nand_ecclayout onenand_oob_32 = {
  	.eccbytes	= 10,
  	.eccpos		= {
  		8, 9, 10, 11, 12,
  		24, 25, 26, 27, 28,
  		},
  	.oobfree	= { {2, 3}, {14, 2}, {18, 3}, {30, 2} }
  };
  
  static const unsigned char ffchars[] = {
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 16 */
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 32 */
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 48 */
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 64 */
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 80 */
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 96 */
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 112 */
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
  	0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* 128 */
  };
  
  /**
   * onenand_readw - [OneNAND Interface] Read OneNAND register
   * @param addr		address to read
   *
   * Read OneNAND register
   */
  static unsigned short onenand_readw(void __iomem *addr)
  {
  	return readw(addr);
  }
  
  /**
   * onenand_writew - [OneNAND Interface] Write OneNAND register with value
   * @param value		value to write
   * @param addr		address to write
   *
   * Write OneNAND register with value
   */
  static void onenand_writew(unsigned short value, void __iomem *addr)
  {
  	writew(value, addr);
  }
  
  /**
   * onenand_block_address - [DEFAULT] Get block address
   * @param this		onenand chip data structure
   * @param block		the block
   * @return		translated block address if DDP, otherwise same
   *
   * Setup Start Address 1 Register (F100h)
   */
  static int onenand_block_address(struct onenand_chip *this, int block)
  {
  	/* Device Flash Core select, NAND Flash Block Address */
  	if (block & this->density_mask)
  		return ONENAND_DDP_CHIP1 | (block ^ this->density_mask);
  
  	return block;
  }
  
  /**
   * onenand_bufferram_address - [DEFAULT] Get bufferram address
   * @param this		onenand chip data structure
   * @param block		the block
   * @return		set DBS value if DDP, otherwise 0
   *
   * Setup Start Address 2 Register (F101h) for DDP
   */
  static int onenand_bufferram_address(struct onenand_chip *this, int block)
  {
  	/* Device BufferRAM Select */
  	if (block & this->density_mask)
  		return ONENAND_DDP_CHIP1;
  
  	return ONENAND_DDP_CHIP0;
  }
  
  /**
   * onenand_page_address - [DEFAULT] Get page address
   * @param page		the page address
   * @param sector	the sector address
   * @return		combined page and sector address
   *
   * Setup Start Address 8 Register (F107h)
   */
  static int onenand_page_address(int page, int sector)
  {
  	/* Flash Page Address, Flash Sector Address */
  	int fpa, fsa;
  
  	fpa = page & ONENAND_FPA_MASK;
  	fsa = sector & ONENAND_FSA_MASK;
  
  	return ((fpa << ONENAND_FPA_SHIFT) | fsa);
  }
  
  /**
   * onenand_buffer_address - [DEFAULT] Get buffer address
   * @param dataram1	DataRAM index
   * @param sectors	the sector address
   * @param count		the number of sectors
   * @return		the start buffer value
   *
   * Setup Start Buffer Register (F200h)
   */
  static int onenand_buffer_address(int dataram1, int sectors, int count)
  {
  	int bsa, bsc;
  
  	/* BufferRAM Sector Address */
  	bsa = sectors & ONENAND_BSA_MASK;
  
  	if (dataram1)
  		bsa |= ONENAND_BSA_DATARAM1;	/* DataRAM1 */
  	else
  		bsa |= ONENAND_BSA_DATARAM0;	/* DataRAM0 */
  
  	/* BufferRAM Sector Count */
  	bsc = count & ONENAND_BSC_MASK;
  
  	return ((bsa << ONENAND_BSA_SHIFT) | bsc);
  }
  
  /**
   * flexonenand_block- For given address return block number
   * @param this         - OneNAND device structure
   * @param addr		- Address for which block number is needed
   */
  static unsigned flexonenand_block(struct onenand_chip *this, loff_t addr)
  {
  	unsigned boundary, blk, die = 0;
  
  	if (ONENAND_IS_DDP(this) && addr >= this->diesize[0]) {
  		die = 1;
  		addr -= this->diesize[0];
  	}
  
  	boundary = this->boundary[die];
  
  	blk = addr >> (this->erase_shift - 1);
  	if (blk > boundary)
  		blk = (blk + boundary + 1) >> 1;
  
  	blk += die ? this->density_mask : 0;
  	return blk;
  }
  
  inline unsigned onenand_block(struct onenand_chip *this, loff_t addr)
  {
  	if (!FLEXONENAND(this))
  		return addr >> this->erase_shift;
  	return flexonenand_block(this, addr);
  }
  
  /**
   * flexonenand_addr - Return address of the block
   * @this:		OneNAND device structure
   * @block:		Block number on Flex-OneNAND
   *
   * Return address of the block
   */
  static loff_t flexonenand_addr(struct onenand_chip *this, int block)
  {
  	loff_t ofs = 0;
  	int die = 0, boundary;
  
  	if (ONENAND_IS_DDP(this) && block >= this->density_mask) {
  		block -= this->density_mask;
  		die = 1;
  		ofs = this->diesize[0];
  	}
  
  	boundary = this->boundary[die];
  	ofs += (loff_t)block << (this->erase_shift - 1);
  	if (block > (boundary + 1))
  		ofs += (loff_t)(block - boundary - 1) << (this->erase_shift - 1);
  	return ofs;
  }
  
  loff_t onenand_addr(struct onenand_chip *this, int block)
  {
  	if (!FLEXONENAND(this))
  		return (loff_t)block << this->erase_shift;
  	return flexonenand_addr(this, block);
  }
  EXPORT_SYMBOL(onenand_addr);
  
  /**
   * onenand_get_density - [DEFAULT] Get OneNAND density
   * @param dev_id	OneNAND device ID
   *
   * Get OneNAND density from device ID
   */
  static inline int onenand_get_density(int dev_id)
  {
  	int density = dev_id >> ONENAND_DEVICE_DENSITY_SHIFT;
  	return (density & ONENAND_DEVICE_DENSITY_MASK);
  }
  
  /**
   * flexonenand_region - [Flex-OneNAND] Return erase region of addr
   * @param mtd		MTD device structure
   * @param addr		address whose erase region needs to be identified
   */
  int flexonenand_region(struct mtd_info *mtd, loff_t addr)
  {
  	int i;
  
  	for (i = 0; i < mtd->numeraseregions; i++)
  		if (addr < mtd->eraseregions[i].offset)
  			break;
  	return i - 1;
  }
  EXPORT_SYMBOL(flexonenand_region);
  
  /**
   * onenand_command - [DEFAULT] Send command to OneNAND device
   * @param mtd		MTD device structure
   * @param cmd		the command to be sent
   * @param addr		offset to read from or write to
   * @param len		number of bytes to read or write
   *
   * Send command to OneNAND device. This function is used for middle/large page
   * devices (1KB/2KB Bytes per page)
   */
  static int onenand_command(struct mtd_info *mtd, int cmd, loff_t addr, size_t len)
  {
  	struct onenand_chip *this = mtd->priv;
  	int value, block, page;
  
  	/* Address translation */
  	switch (cmd) {
  	case ONENAND_CMD_UNLOCK:
  	case ONENAND_CMD_LOCK:
  	case ONENAND_CMD_LOCK_TIGHT:
  	case ONENAND_CMD_UNLOCK_ALL:
  		block = -1;
  		page = -1;
  		break;
  
  	case FLEXONENAND_CMD_PI_ACCESS:
  		/* addr contains die index */
  		block = addr * this->density_mask;
  		page = -1;
  		break;
  
  	case ONENAND_CMD_ERASE:
  	case ONENAND_CMD_MULTIBLOCK_ERASE:
  	case ONENAND_CMD_ERASE_VERIFY:
  	case ONENAND_CMD_BUFFERRAM:
  	case ONENAND_CMD_OTP_ACCESS:
  		block = onenand_block(this, addr);
  		page = -1;
  		break;
  
  	case FLEXONENAND_CMD_READ_PI:
  		cmd = ONENAND_CMD_READ;
  		block = addr * this->density_mask;
  		page = 0;
  		break;
  
  	default:
  		block = onenand_block(this, addr);
  		if (FLEXONENAND(this))
  			page = (int) (addr - onenand_addr(this, block))>>\
  				this->page_shift;
  		else
  			page = (int) (addr >> this->page_shift);
  		if (ONENAND_IS_2PLANE(this)) {
  			/* Make the even block number */
  			block &= ~1;
  			/* Is it the odd plane? */
  			if (addr & this->writesize)
  				block++;
  			page >>= 1;
  		}
  		page &= this->page_mask;
  		break;
  	}
  
  	/* NOTE: The setting order of the registers is very important! */
  	if (cmd == ONENAND_CMD_BUFFERRAM) {
  		/* Select DataRAM for DDP */
  		value = onenand_bufferram_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
  
  		if (ONENAND_IS_2PLANE(this) || ONENAND_IS_4KB_PAGE(this))
  			/* It is always BufferRAM0 */
  			ONENAND_SET_BUFFERRAM0(this);
  		else
  			/* Switch to the next data buffer */
  			ONENAND_SET_NEXT_BUFFERRAM(this);
  
  		return 0;
  	}
  
  	if (block != -1) {
  		/* Write 'DFS, FBA' of Flash */
  		value = onenand_block_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
  
  		/* Select DataRAM for DDP */
  		value = onenand_bufferram_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
  	}
  
  	if (page != -1) {
  		/* Now we use page size operation */
  		int sectors = 0, count = 0;
  		int dataram;
  
  		switch (cmd) {
  		case FLEXONENAND_CMD_RECOVER_LSB:
  		case ONENAND_CMD_READ:
  		case ONENAND_CMD_READOOB:
  			if (ONENAND_IS_4KB_PAGE(this))
  				/* It is always BufferRAM0 */
  				dataram = ONENAND_SET_BUFFERRAM0(this);
  			else
  				dataram = ONENAND_SET_NEXT_BUFFERRAM(this);
  			break;
  
  		default:
  			if (ONENAND_IS_2PLANE(this) && cmd == ONENAND_CMD_PROG)
  				cmd = ONENAND_CMD_2X_PROG;
  			dataram = ONENAND_CURRENT_BUFFERRAM(this);
  			break;
  		}
  
  		/* Write 'FPA, FSA' of Flash */
  		value = onenand_page_address(page, sectors);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS8);
  
  		/* Write 'BSA, BSC' of DataRAM */
  		value = onenand_buffer_address(dataram, sectors, count);
  		this->write_word(value, this->base + ONENAND_REG_START_BUFFER);
  	}
  
  	/* Interrupt clear */
  	this->write_word(ONENAND_INT_CLEAR, this->base + ONENAND_REG_INTERRUPT);
  
  	/* Write command */
  	this->write_word(cmd, this->base + ONENAND_REG_COMMAND);
  
  	return 0;
  }
  
  /**
   * onenand_read_ecc - return ecc status
   * @param this		onenand chip structure
   */
  static inline int onenand_read_ecc(struct onenand_chip *this)
  {
  	int ecc, i, result = 0;
  
  	if (!FLEXONENAND(this) && !ONENAND_IS_4KB_PAGE(this))
  		return this->read_word(this->base + ONENAND_REG_ECC_STATUS);
  
  	for (i = 0; i < 4; i++) {
  		ecc = this->read_word(this->base + ONENAND_REG_ECC_STATUS + i*2);
  		if (likely(!ecc))
  			continue;
  		if (ecc & FLEXONENAND_UNCORRECTABLE_ERROR)
  			return ONENAND_ECC_2BIT_ALL;
  		else
  			result = ONENAND_ECC_1BIT_ALL;
  	}
  
  	return result;
  }
  
  /**
   * onenand_wait - [DEFAULT] wait until the command is done
   * @param mtd		MTD device structure
   * @param state		state to select the max. timeout value
   *
   * Wait for command done. This applies to all OneNAND command
   * Read can take up to 30us, erase up to 2ms and program up to 350us
   * according to general OneNAND specs
   */
  static int onenand_wait(struct mtd_info *mtd, int state)
  {
  	struct onenand_chip * this = mtd->priv;
  	unsigned long timeout;
  	unsigned int flags = ONENAND_INT_MASTER;
  	unsigned int interrupt = 0;
  	unsigned int ctrl;
  
  	/* The 20 msec is enough */
  	timeout = jiffies + msecs_to_jiffies(20);
  	while (time_before(jiffies, timeout)) {
  		interrupt = this->read_word(this->base + ONENAND_REG_INTERRUPT);
  
  		if (interrupt & flags)
  			break;
  
  		if (state != FL_READING && state != FL_PREPARING_ERASE)
  			cond_resched();
  	}
  	/* To get correct interrupt status in timeout case */
  	interrupt = this->read_word(this->base + ONENAND_REG_INTERRUPT);
  
  	ctrl = this->read_word(this->base + ONENAND_REG_CTRL_STATUS);
  
  	/*
  	 * In the Spec. it checks the controller status first
  	 * However if you get the correct information in case of
  	 * power off recovery (POR) test, it should read ECC status first
  	 */
  	if (interrupt & ONENAND_INT_READ) {
  		int ecc = onenand_read_ecc(this);
  		if (ecc) {
  			if (ecc & ONENAND_ECC_2BIT_ALL) {
  				printk(KERN_ERR "%s: ECC error = 0x%04x\n",
  					__func__, ecc);
  				mtd->ecc_stats.failed++;
  				return -EBADMSG;
  			} else if (ecc & ONENAND_ECC_1BIT_ALL) {
  				printk(KERN_DEBUG "%s: correctable ECC error = 0x%04x\n",
  					__func__, ecc);
  				mtd->ecc_stats.corrected++;
  			}
  		}
  	} else if (state == FL_READING) {
  		printk(KERN_ERR "%s: read timeout! ctrl=0x%04x intr=0x%04x\n",
  			__func__, ctrl, interrupt);
  		return -EIO;
  	}
  
  	if (state == FL_PREPARING_ERASE && !(interrupt & ONENAND_INT_ERASE)) {
  		printk(KERN_ERR "%s: mb erase timeout! ctrl=0x%04x intr=0x%04x\n",
  		       __func__, ctrl, interrupt);
  		return -EIO;
  	}
  
  	if (!(interrupt & ONENAND_INT_MASTER)) {
  		printk(KERN_ERR "%s: timeout! ctrl=0x%04x intr=0x%04x\n",
  		       __func__, ctrl, interrupt);
  		return -EIO;
  	}
  
  	/* If there's controller error, it's a real error */
  	if (ctrl & ONENAND_CTRL_ERROR) {
  		printk(KERN_ERR "%s: controller error = 0x%04x\n",
  			__func__, ctrl);
  		if (ctrl & ONENAND_CTRL_LOCK)
  			printk(KERN_ERR "%s: it's locked error.\n", __func__);
  		return -EIO;
  	}
  
  	return 0;
  }
  
  /*
   * onenand_interrupt - [DEFAULT] onenand interrupt handler
   * @param irq		onenand interrupt number
   * @param dev_id	interrupt data
   *
   * complete the work
   */
  static irqreturn_t onenand_interrupt(int irq, void *data)
  {
  	struct onenand_chip *this = data;
  
  	/* To handle shared interrupt */
  	if (!this->complete.done)
  		complete(&this->complete);
  
  	return IRQ_HANDLED;
  }
  
  /*
   * onenand_interrupt_wait - [DEFAULT] wait until the command is done
   * @param mtd		MTD device structure
   * @param state		state to select the max. timeout value
   *
   * Wait for command done.
   */
  static int onenand_interrupt_wait(struct mtd_info *mtd, int state)
  {
  	struct onenand_chip *this = mtd->priv;
  
  	wait_for_completion(&this->complete);
  
  	return onenand_wait(mtd, state);
  }
  
  /*
   * onenand_try_interrupt_wait - [DEFAULT] try interrupt wait
   * @param mtd		MTD device structure
   * @param state		state to select the max. timeout value
   *
   * Try interrupt based wait (It is used one-time)
   */
  static int onenand_try_interrupt_wait(struct mtd_info *mtd, int state)
  {
  	struct onenand_chip *this = mtd->priv;
  	unsigned long remain, timeout;
  
  	/* We use interrupt wait first */
  	this->wait = onenand_interrupt_wait;
  
  	timeout = msecs_to_jiffies(100);
  	remain = wait_for_completion_timeout(&this->complete, timeout);
  	if (!remain) {
  		printk(KERN_INFO "OneNAND: There's no interrupt. "
  				"We use the normal wait\n");
  
  		/* Release the irq */
  		free_irq(this->irq, this);
  
  		this->wait = onenand_wait;
  	}
  
  	return onenand_wait(mtd, state);
  }
  
  /*
   * onenand_setup_wait - [OneNAND Interface] setup onenand wait method
   * @param mtd		MTD device structure
   *
   * There's two method to wait onenand work
   * 1. polling - read interrupt status register
   * 2. interrupt - use the kernel interrupt method
   */
  static void onenand_setup_wait(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	int syscfg;
  
  	init_completion(&this->complete);
  
  	if (this->irq <= 0) {
  		this->wait = onenand_wait;
  		return;
  	}
  
  	if (request_irq(this->irq, &onenand_interrupt,
  				IRQF_SHARED, "onenand", this)) {
  		/* If we can't get irq, use the normal wait */
  		this->wait = onenand_wait;
  		return;
  	}
  
  	/* Enable interrupt */
  	syscfg = this->read_word(this->base + ONENAND_REG_SYS_CFG1);
  	syscfg |= ONENAND_SYS_CFG1_IOBE;
  	this->write_word(syscfg, this->base + ONENAND_REG_SYS_CFG1);
  
  	this->wait = onenand_try_interrupt_wait;
  }
  
  /**
   * onenand_bufferram_offset - [DEFAULT] BufferRAM offset
   * @param mtd		MTD data structure
   * @param area		BufferRAM area
   * @return		offset given area
   *
   * Return BufferRAM offset given area
   */
  static inline int onenand_bufferram_offset(struct mtd_info *mtd, int area)
  {
  	struct onenand_chip *this = mtd->priv;
  
  	if (ONENAND_CURRENT_BUFFERRAM(this)) {
  		/* Note: the 'this->writesize' is a real page size */
  		if (area == ONENAND_DATARAM)
  			return this->writesize;
  		if (area == ONENAND_SPARERAM)
  			return mtd->oobsize;
  	}
  
  	return 0;
  }
  
  /**
   * onenand_read_bufferram - [OneNAND Interface] Read the bufferram area
   * @param mtd		MTD data structure
   * @param area		BufferRAM area
   * @param buffer	the databuffer to put/get data
   * @param offset	offset to read from or write to
   * @param count		number of bytes to read/write
   *
   * Read the BufferRAM area
   */
  static int onenand_read_bufferram(struct mtd_info *mtd, int area,
  		unsigned char *buffer, int offset, size_t count)
  {
  	struct onenand_chip *this = mtd->priv;
  	void __iomem *bufferram;
  
  	bufferram = this->base + area;
  
  	bufferram += onenand_bufferram_offset(mtd, area);
  
  	if (ONENAND_CHECK_BYTE_ACCESS(count)) {
  		unsigned short word;
  
  		/* Align with word(16-bit) size */
  		count--;
  
  		/* Read word and save byte */
  		word = this->read_word(bufferram + offset + count);
  		buffer[count] = (word & 0xff);
  	}
  
  	memcpy(buffer, bufferram + offset, count);
  
  	return 0;
  }
  
  /**
   * onenand_sync_read_bufferram - [OneNAND Interface] Read the bufferram area with Sync. Burst mode
   * @param mtd		MTD data structure
   * @param area		BufferRAM area
   * @param buffer	the databuffer to put/get data
   * @param offset	offset to read from or write to
   * @param count		number of bytes to read/write
   *
   * Read the BufferRAM area with Sync. Burst Mode
   */
  static int onenand_sync_read_bufferram(struct mtd_info *mtd, int area,
  		unsigned char *buffer, int offset, size_t count)
  {
  	struct onenand_chip *this = mtd->priv;
  	void __iomem *bufferram;
  
  	bufferram = this->base + area;
  
  	bufferram += onenand_bufferram_offset(mtd, area);
  
  	this->mmcontrol(mtd, ONENAND_SYS_CFG1_SYNC_READ);
  
  	if (ONENAND_CHECK_BYTE_ACCESS(count)) {
  		unsigned short word;
  
  		/* Align with word(16-bit) size */
  		count--;
  
  		/* Read word and save byte */
  		word = this->read_word(bufferram + offset + count);
  		buffer[count] = (word & 0xff);
  	}
  
  	memcpy(buffer, bufferram + offset, count);
  
  	this->mmcontrol(mtd, 0);
  
  	return 0;
  }
  
  /**
   * onenand_write_bufferram - [OneNAND Interface] Write the bufferram area
   * @param mtd		MTD data structure
   * @param area		BufferRAM area
   * @param buffer	the databuffer to put/get data
   * @param offset	offset to read from or write to
   * @param count		number of bytes to read/write
   *
   * Write the BufferRAM area
   */
  static int onenand_write_bufferram(struct mtd_info *mtd, int area,
  		const unsigned char *buffer, int offset, size_t count)
  {
  	struct onenand_chip *this = mtd->priv;
  	void __iomem *bufferram;
  
  	bufferram = this->base + area;
  
  	bufferram += onenand_bufferram_offset(mtd, area);
  
  	if (ONENAND_CHECK_BYTE_ACCESS(count)) {
  		unsigned short word;
  		int byte_offset;
  
  		/* Align with word(16-bit) size */
  		count--;
  
  		/* Calculate byte access offset */
  		byte_offset = offset + count;
  
  		/* Read word and save byte */
  		word = this->read_word(bufferram + byte_offset);
  		word = (word & ~0xff) | buffer[count];
  		this->write_word(word, bufferram + byte_offset);
  	}
  
  	memcpy(bufferram + offset, buffer, count);
  
  	return 0;
  }
  
  /**
   * onenand_get_2x_blockpage - [GENERIC] Get blockpage at 2x program mode
   * @param mtd		MTD data structure
   * @param addr		address to check
   * @return		blockpage address
   *
   * Get blockpage address at 2x program mode
   */
  static int onenand_get_2x_blockpage(struct mtd_info *mtd, loff_t addr)
  {
  	struct onenand_chip *this = mtd->priv;
  	int blockpage, block, page;
  
  	/* Calculate the even block number */
  	block = (int) (addr >> this->erase_shift) & ~1;
  	/* Is it the odd plane? */
  	if (addr & this->writesize)
  		block++;
  	page = (int) (addr >> (this->page_shift + 1)) & this->page_mask;
  	blockpage = (block << 7) | page;
  
  	return blockpage;
  }
  
  /**
   * onenand_check_bufferram - [GENERIC] Check BufferRAM information
   * @param mtd		MTD data structure
   * @param addr		address to check
   * @return		1 if there are valid data, otherwise 0
   *
   * Check bufferram if there is data we required
   */
  static int onenand_check_bufferram(struct mtd_info *mtd, loff_t addr)
  {
  	struct onenand_chip *this = mtd->priv;
  	int blockpage, found = 0;
  	unsigned int i;
  
  	if (ONENAND_IS_2PLANE(this))
  		blockpage = onenand_get_2x_blockpage(mtd, addr);
  	else
  		blockpage = (int) (addr >> this->page_shift);
  
  	/* Is there valid data? */
  	i = ONENAND_CURRENT_BUFFERRAM(this);
  	if (this->bufferram[i].blockpage == blockpage)
  		found = 1;
  	else {
  		/* Check another BufferRAM */
  		i = ONENAND_NEXT_BUFFERRAM(this);
  		if (this->bufferram[i].blockpage == blockpage) {
  			ONENAND_SET_NEXT_BUFFERRAM(this);
  			found = 1;
  		}
  	}
  
  	if (found && ONENAND_IS_DDP(this)) {
  		/* Select DataRAM for DDP */
  		int block = onenand_block(this, addr);
  		int value = onenand_bufferram_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
  	}
  
  	return found;
  }
  
  /**
   * onenand_update_bufferram - [GENERIC] Update BufferRAM information
   * @param mtd		MTD data structure
   * @param addr		address to update
   * @param valid		valid flag
   *
   * Update BufferRAM information
   */
  static void onenand_update_bufferram(struct mtd_info *mtd, loff_t addr,
  		int valid)
  {
  	struct onenand_chip *this = mtd->priv;
  	int blockpage;
  	unsigned int i;
  
  	if (ONENAND_IS_2PLANE(this))
  		blockpage = onenand_get_2x_blockpage(mtd, addr);
  	else
  		blockpage = (int) (addr >> this->page_shift);
  
  	/* Invalidate another BufferRAM */
  	i = ONENAND_NEXT_BUFFERRAM(this);
  	if (this->bufferram[i].blockpage == blockpage)
  		this->bufferram[i].blockpage = -1;
  
  	/* Update BufferRAM */
  	i = ONENAND_CURRENT_BUFFERRAM(this);
  	if (valid)
  		this->bufferram[i].blockpage = blockpage;
  	else
  		this->bufferram[i].blockpage = -1;
  }
  
  /**
   * onenand_invalidate_bufferram - [GENERIC] Invalidate BufferRAM information
   * @param mtd		MTD data structure
   * @param addr		start address to invalidate
   * @param len		length to invalidate
   *
   * Invalidate BufferRAM information
   */
  static void onenand_invalidate_bufferram(struct mtd_info *mtd, loff_t addr,
  		unsigned int len)
  {
  	struct onenand_chip *this = mtd->priv;
  	int i;
  	loff_t end_addr = addr + len;
  
  	/* Invalidate BufferRAM */
  	for (i = 0; i < MAX_BUFFERRAM; i++) {
  		loff_t buf_addr = this->bufferram[i].blockpage << this->page_shift;
  		if (buf_addr >= addr && buf_addr < end_addr)
  			this->bufferram[i].blockpage = -1;
  	}
  }
  
  /**
   * onenand_get_device - [GENERIC] Get chip for selected access
   * @param mtd		MTD device structure
   * @param new_state	the state which is requested
   *
   * Get the device and lock it for exclusive access
   */
  static int onenand_get_device(struct mtd_info *mtd, int new_state)
  {
  	struct onenand_chip *this = mtd->priv;
  	DECLARE_WAITQUEUE(wait, current);
  
  	/*
  	 * Grab the lock and see if the device is available
  	 */
  	while (1) {
  		spin_lock(&this->chip_lock);
  		if (this->state == FL_READY) {
  			this->state = new_state;
  			spin_unlock(&this->chip_lock);
  			if (new_state != FL_PM_SUSPENDED && this->enable)
  				this->enable(mtd);
  			break;
  		}
  		if (new_state == FL_PM_SUSPENDED) {
  			spin_unlock(&this->chip_lock);
  			return (this->state == FL_PM_SUSPENDED) ? 0 : -EAGAIN;
  		}
  		set_current_state(TASK_UNINTERRUPTIBLE);
  		add_wait_queue(&this->wq, &wait);
  		spin_unlock(&this->chip_lock);
  		schedule();
  		remove_wait_queue(&this->wq, &wait);
  	}
  
  	return 0;
  }
  
  /**
   * onenand_release_device - [GENERIC] release chip
   * @param mtd		MTD device structure
   *
   * Deselect, release chip lock and wake up anyone waiting on the device
   */
  static void onenand_release_device(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  
  	if (this->state != FL_PM_SUSPENDED && this->disable)
  		this->disable(mtd);
  	/* Release the chip */
  	spin_lock(&this->chip_lock);
  	this->state = FL_READY;
  	wake_up(&this->wq);
  	spin_unlock(&this->chip_lock);
  }
  
  /**
   * onenand_transfer_auto_oob - [INTERN] oob auto-placement transfer
   * @param mtd		MTD device structure
   * @param buf		destination address
   * @param column	oob offset to read from
   * @param thislen	oob length to read
   */
  static int onenand_transfer_auto_oob(struct mtd_info *mtd, uint8_t *buf, int column,
  				int thislen)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct nand_oobfree *free;
  	int readcol = column;
  	int readend = column + thislen;
  	int lastgap = 0;
  	unsigned int i;
  	uint8_t *oob_buf = this->oob_buf;
  
  	free = this->ecclayout->oobfree;
  	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES && free->length; i++, free++) {
  		if (readcol >= lastgap)
  			readcol += free->offset - lastgap;
  		if (readend >= lastgap)
  			readend += free->offset - lastgap;
  		lastgap = free->offset + free->length;
  	}
  	this->read_bufferram(mtd, ONENAND_SPARERAM, oob_buf, 0, mtd->oobsize);
  	free = this->ecclayout->oobfree;
  	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES && free->length; i++, free++) {
  		int free_end = free->offset + free->length;
  		if (free->offset < readend && free_end > readcol) {
  			int st = max_t(int,free->offset,readcol);
  			int ed = min_t(int,free_end,readend);
  			int n = ed - st;
  			memcpy(buf, oob_buf + st, n);
  			buf += n;
  		} else if (column == 0)
  			break;
  	}
  	return 0;
  }
  
  /**
   * onenand_recover_lsb - [Flex-OneNAND] Recover LSB page data
   * @param mtd		MTD device structure
   * @param addr		address to recover
   * @param status	return value from onenand_wait / onenand_bbt_wait
   *
   * MLC NAND Flash cell has paired pages - LSB page and MSB page. LSB page has
   * lower page address and MSB page has higher page address in paired pages.
   * If power off occurs during MSB page program, the paired LSB page data can
   * become corrupt. LSB page recovery read is a way to read LSB page though page
   * data are corrupted. When uncorrectable error occurs as a result of LSB page
   * read after power up, issue LSB page recovery read.
   */
  static int onenand_recover_lsb(struct mtd_info *mtd, loff_t addr, int status)
  {
  	struct onenand_chip *this = mtd->priv;
  	int i;
  
  	/* Recovery is only for Flex-OneNAND */
  	if (!FLEXONENAND(this))
  		return status;
  
  	/* check if we failed due to uncorrectable error */
  	if (!mtd_is_eccerr(status) && status != ONENAND_BBT_READ_ECC_ERROR)
  		return status;
  
  	/* check if address lies in MLC region */
  	i = flexonenand_region(mtd, addr);
  	if (mtd->eraseregions[i].erasesize < (1 << this->erase_shift))
  		return status;
  
  	/* We are attempting to reread, so decrement stats.failed
  	 * which was incremented by onenand_wait due to read failure
  	 */
  	printk(KERN_INFO "%s: Attempting to recover from uncorrectable read\n",
  		__func__);
  	mtd->ecc_stats.failed--;
  
  	/* Issue the LSB page recovery command */
  	this->command(mtd, FLEXONENAND_CMD_RECOVER_LSB, addr, this->writesize);
  	return this->wait(mtd, FL_READING);
  }
  
  /**
   * onenand_mlc_read_ops_nolock - MLC OneNAND read main and/or out-of-band
   * @param mtd		MTD device structure
   * @param from		offset to read from
   * @param ops:		oob operation description structure
   *
   * MLC OneNAND / Flex-OneNAND has 4KB page size and 4KB dataram.
   * So, read-while-load is not present.
   */
  static int onenand_mlc_read_ops_nolock(struct mtd_info *mtd, loff_t from,
  				struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct mtd_ecc_stats stats;
  	size_t len = ops->len;
  	size_t ooblen = ops->ooblen;
  	u_char *buf = ops->datbuf;
  	u_char *oobbuf = ops->oobbuf;
  	int read = 0, column, thislen;
  	int oobread = 0, oobcolumn, thisooblen, oobsize;
  	int ret = 0;
  	int writesize = this->writesize;
  
  	pr_debug("%s: from = 0x%08x, len = %i\n", __func__, (unsigned int)from,
  			(int)len);
  
  	if (ops->mode == MTD_OPS_AUTO_OOB)
  		oobsize = this->ecclayout->oobavail;
  	else
  		oobsize = mtd->oobsize;
  
  	oobcolumn = from & (mtd->oobsize - 1);
  
  	/* Do not allow reads past end of device */
  	if (from + len > mtd->size) {
  		printk(KERN_ERR "%s: Attempt read beyond end of device\n",
  			__func__);
  		ops->retlen = 0;
  		ops->oobretlen = 0;
  		return -EINVAL;
  	}
  
  	stats = mtd->ecc_stats;
  
  	while (read < len) {
  		cond_resched();
  
  		thislen = min_t(int, writesize, len - read);
  
  		column = from & (writesize - 1);
  		if (column + thislen > writesize)
  			thislen = writesize - column;
  
  		if (!onenand_check_bufferram(mtd, from)) {
  			this->command(mtd, ONENAND_CMD_READ, from, writesize);
  
  			ret = this->wait(mtd, FL_READING);
  			if (unlikely(ret))
  				ret = onenand_recover_lsb(mtd, from, ret);
  			onenand_update_bufferram(mtd, from, !ret);
  			if (mtd_is_eccerr(ret))
  				ret = 0;
  			if (ret)
  				break;
  		}
  
  		this->read_bufferram(mtd, ONENAND_DATARAM, buf, column, thislen);
  		if (oobbuf) {
  			thisooblen = oobsize - oobcolumn;
  			thisooblen = min_t(int, thisooblen, ooblen - oobread);
  
  			if (ops->mode == MTD_OPS_AUTO_OOB)
  				onenand_transfer_auto_oob(mtd, oobbuf, oobcolumn, thisooblen);
  			else
  				this->read_bufferram(mtd, ONENAND_SPARERAM, oobbuf, oobcolumn, thisooblen);
  			oobread += thisooblen;
  			oobbuf += thisooblen;
  			oobcolumn = 0;
  		}
  
  		read += thislen;
  		if (read == len)
  			break;
  
  		from += thislen;
  		buf += thislen;
  	}
  
  	/*
  	 * Return success, if no ECC failures, else -EBADMSG
  	 * fs driver will take care of that, because
  	 * retlen == desired len and result == -EBADMSG
  	 */
  	ops->retlen = read;
  	ops->oobretlen = oobread;
  
  	if (ret)
  		return ret;
  
  	if (mtd->ecc_stats.failed - stats.failed)
  		return -EBADMSG;
  
  	/* return max bitflips per ecc step; ONENANDs correct 1 bit only */
  	return mtd->ecc_stats.corrected != stats.corrected ? 1 : 0;
  }
  
  /**
   * onenand_read_ops_nolock - [OneNAND Interface] OneNAND read main and/or out-of-band
   * @param mtd		MTD device structure
   * @param from		offset to read from
   * @param ops:		oob operation description structure
   *
   * OneNAND read main and/or out-of-band data
   */
  static int onenand_read_ops_nolock(struct mtd_info *mtd, loff_t from,
  				struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct mtd_ecc_stats stats;
  	size_t len = ops->len;
  	size_t ooblen = ops->ooblen;
  	u_char *buf = ops->datbuf;
  	u_char *oobbuf = ops->oobbuf;
  	int read = 0, column, thislen;
  	int oobread = 0, oobcolumn, thisooblen, oobsize;
  	int ret = 0, boundary = 0;
  	int writesize = this->writesize;
  
  	pr_debug("%s: from = 0x%08x, len = %i\n", __func__, (unsigned int)from,
  			(int)len);
  
  	if (ops->mode == MTD_OPS_AUTO_OOB)
  		oobsize = this->ecclayout->oobavail;
  	else
  		oobsize = mtd->oobsize;
  
  	oobcolumn = from & (mtd->oobsize - 1);
  
  	/* Do not allow reads past end of device */
  	if ((from + len) > mtd->size) {
  		printk(KERN_ERR "%s: Attempt read beyond end of device\n",
  			__func__);
  		ops->retlen = 0;
  		ops->oobretlen = 0;
  		return -EINVAL;
  	}
  
  	stats = mtd->ecc_stats;
  
   	/* Read-while-load method */
  
   	/* Do first load to bufferRAM */
   	if (read < len) {
   		if (!onenand_check_bufferram(mtd, from)) {
  			this->command(mtd, ONENAND_CMD_READ, from, writesize);
   			ret = this->wait(mtd, FL_READING);
   			onenand_update_bufferram(mtd, from, !ret);
  			if (mtd_is_eccerr(ret))
  				ret = 0;
   		}
   	}
  
  	thislen = min_t(int, writesize, len - read);
  	column = from & (writesize - 1);
  	if (column + thislen > writesize)
  		thislen = writesize - column;
  
   	while (!ret) {
   		/* If there is more to load then start next load */
   		from += thislen;
   		if (read + thislen < len) {
  			this->command(mtd, ONENAND_CMD_READ, from, writesize);
   			/*
   			 * Chip boundary handling in DDP
   			 * Now we issued chip 1 read and pointed chip 1
  			 * bufferram so we have to point chip 0 bufferram.
   			 */
   			if (ONENAND_IS_DDP(this) &&
   			    unlikely(from == (this->chipsize >> 1))) {
   				this->write_word(ONENAND_DDP_CHIP0, this->base + ONENAND_REG_START_ADDRESS2);
   				boundary = 1;
   			} else
   				boundary = 0;
   			ONENAND_SET_PREV_BUFFERRAM(this);
   		}
   		/* While load is going, read from last bufferRAM */
   		this->read_bufferram(mtd, ONENAND_DATARAM, buf, column, thislen);
  
  		/* Read oob area if needed */
  		if (oobbuf) {
  			thisooblen = oobsize - oobcolumn;
  			thisooblen = min_t(int, thisooblen, ooblen - oobread);
  
  			if (ops->mode == MTD_OPS_AUTO_OOB)
  				onenand_transfer_auto_oob(mtd, oobbuf, oobcolumn, thisooblen);
  			else
  				this->read_bufferram(mtd, ONENAND_SPARERAM, oobbuf, oobcolumn, thisooblen);
  			oobread += thisooblen;
  			oobbuf += thisooblen;
  			oobcolumn = 0;
  		}
  
   		/* See if we are done */
   		read += thislen;
   		if (read == len)
   			break;
   		/* Set up for next read from bufferRAM */
   		if (unlikely(boundary))
   			this->write_word(ONENAND_DDP_CHIP1, this->base + ONENAND_REG_START_ADDRESS2);
   		ONENAND_SET_NEXT_BUFFERRAM(this);
   		buf += thislen;
  		thislen = min_t(int, writesize, len - read);
   		column = 0;
   		cond_resched();
   		/* Now wait for load */
   		ret = this->wait(mtd, FL_READING);
   		onenand_update_bufferram(mtd, from, !ret);
  		if (mtd_is_eccerr(ret))
  			ret = 0;
   	}
  
  	/*
  	 * Return success, if no ECC failures, else -EBADMSG
  	 * fs driver will take care of that, because
  	 * retlen == desired len and result == -EBADMSG
  	 */
  	ops->retlen = read;
  	ops->oobretlen = oobread;
  
  	if (ret)
  		return ret;
  
  	if (mtd->ecc_stats.failed - stats.failed)
  		return -EBADMSG;
  
  	/* return max bitflips per ecc step; ONENANDs correct 1 bit only */
  	return mtd->ecc_stats.corrected != stats.corrected ? 1 : 0;
  }
  
  /**
   * onenand_read_oob_nolock - [MTD Interface] OneNAND read out-of-band
   * @param mtd		MTD device structure
   * @param from		offset to read from
   * @param ops:		oob operation description structure
   *
   * OneNAND read out-of-band data from the spare area
   */
  static int onenand_read_oob_nolock(struct mtd_info *mtd, loff_t from,
  			struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct mtd_ecc_stats stats;
  	int read = 0, thislen, column, oobsize;
  	size_t len = ops->ooblen;
  	unsigned int mode = ops->mode;
  	u_char *buf = ops->oobbuf;
  	int ret = 0, readcmd;
  
  	from += ops->ooboffs;
  
  	pr_debug("%s: from = 0x%08x, len = %i\n", __func__, (unsigned int)from,
  			(int)len);
  
  	/* Initialize return length value */
  	ops->oobretlen = 0;
  
  	if (mode == MTD_OPS_AUTO_OOB)
  		oobsize = this->ecclayout->oobavail;
  	else
  		oobsize = mtd->oobsize;
  
  	column = from & (mtd->oobsize - 1);
  
  	if (unlikely(column >= oobsize)) {
  		printk(KERN_ERR "%s: Attempted to start read outside oob\n",
  			__func__);
  		return -EINVAL;
  	}
  
  	/* Do not allow reads past end of device */
  	if (unlikely(from >= mtd->size ||
  		     column + len > ((mtd->size >> this->page_shift) -
  				     (from >> this->page_shift)) * oobsize)) {
  		printk(KERN_ERR "%s: Attempted to read beyond end of device\n",
  			__func__);
  		return -EINVAL;
  	}
  
  	stats = mtd->ecc_stats;
  
  	readcmd = ONENAND_IS_4KB_PAGE(this) ? ONENAND_CMD_READ : ONENAND_CMD_READOOB;
  
  	while (read < len) {
  		cond_resched();
  
  		thislen = oobsize - column;
  		thislen = min_t(int, thislen, len);
  
  		this->command(mtd, readcmd, from, mtd->oobsize);
  
  		onenand_update_bufferram(mtd, from, 0);
  
  		ret = this->wait(mtd, FL_READING);
  		if (unlikely(ret))
  			ret = onenand_recover_lsb(mtd, from, ret);
  
  		if (ret && !mtd_is_eccerr(ret)) {
  			printk(KERN_ERR "%s: read failed = 0x%x\n",
  				__func__, ret);
  			break;
  		}
  
  		if (mode == MTD_OPS_AUTO_OOB)
  			onenand_transfer_auto_oob(mtd, buf, column, thislen);
  		else
  			this->read_bufferram(mtd, ONENAND_SPARERAM, buf, column, thislen);
  
  		read += thislen;
  
  		if (read == len)
  			break;
  
  		buf += thislen;
  
  		/* Read more? */
  		if (read < len) {
  			/* Page size */
  			from += mtd->writesize;
  			column = 0;
  		}
  	}
  
  	ops->oobretlen = read;
  
  	if (ret)
  		return ret;
  
  	if (mtd->ecc_stats.failed - stats.failed)
  		return -EBADMSG;
  
  	return 0;
  }
  
  /**
   * onenand_read - [MTD Interface] Read data from flash
   * @param mtd		MTD device structure
   * @param from		offset to read from
   * @param len		number of bytes to read
   * @param retlen	pointer to variable to store the number of read bytes
   * @param buf		the databuffer to put data
   *
   * Read with ecc
  */
  static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
  	size_t *retlen, u_char *buf)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct mtd_oob_ops ops = {
  		.len	= len,
  		.ooblen	= 0,
  		.datbuf	= buf,
  		.oobbuf	= NULL,
  	};
  	int ret;
  
  	onenand_get_device(mtd, FL_READING);
  	ret = ONENAND_IS_4KB_PAGE(this) ?
  		onenand_mlc_read_ops_nolock(mtd, from, &ops) :
  		onenand_read_ops_nolock(mtd, from, &ops);
  	onenand_release_device(mtd);
  
  	*retlen = ops.retlen;
  	return ret;
  }
  
  /**
   * onenand_read_oob - [MTD Interface] Read main and/or out-of-band
   * @param mtd:		MTD device structure
   * @param from:		offset to read from
   * @param ops:		oob operation description structure
  
   * Read main and/or out-of-band
   */
  static int onenand_read_oob(struct mtd_info *mtd, loff_t from,
  			    struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	int ret;
  
  	switch (ops->mode) {
  	case MTD_OPS_PLACE_OOB:
  	case MTD_OPS_AUTO_OOB:
  		break;
  	case MTD_OPS_RAW:
  		/* Not implemented yet */
  	default:
  		return -EINVAL;
  	}
  
  	onenand_get_device(mtd, FL_READING);
  	if (ops->datbuf)
  		ret = ONENAND_IS_4KB_PAGE(this) ?
  			onenand_mlc_read_ops_nolock(mtd, from, ops) :
  			onenand_read_ops_nolock(mtd, from, ops);
  	else
  		ret = onenand_read_oob_nolock(mtd, from, ops);
  	onenand_release_device(mtd);
  
  	return ret;
  }
  
  /**
   * onenand_bbt_wait - [DEFAULT] wait until the command is done
   * @param mtd		MTD device structure
   * @param state		state to select the max. timeout value
   *
   * Wait for command done.
   */
  static int onenand_bbt_wait(struct mtd_info *mtd, int state)
  {
  	struct onenand_chip *this = mtd->priv;
  	unsigned long timeout;
  	unsigned int interrupt, ctrl, ecc, addr1, addr8;
  
  	/* The 20 msec is enough */
  	timeout = jiffies + msecs_to_jiffies(20);
  	while (time_before(jiffies, timeout)) {
  		interrupt = this->read_word(this->base + ONENAND_REG_INTERRUPT);
  		if (interrupt & ONENAND_INT_MASTER)
  			break;
  	}
  	/* To get correct interrupt status in timeout case */
  	interrupt = this->read_word(this->base + ONENAND_REG_INTERRUPT);
  	ctrl = this->read_word(this->base + ONENAND_REG_CTRL_STATUS);
  	addr1 = this->read_word(this->base + ONENAND_REG_START_ADDRESS1);
  	addr8 = this->read_word(this->base + ONENAND_REG_START_ADDRESS8);
  
  	if (interrupt & ONENAND_INT_READ) {
  		ecc = onenand_read_ecc(this);
  		if (ecc & ONENAND_ECC_2BIT_ALL) {
  			printk(KERN_DEBUG "%s: ecc 0x%04x ctrl 0x%04x "
  			       "intr 0x%04x addr1 %#x addr8 %#x\n",
  			       __func__, ecc, ctrl, interrupt, addr1, addr8);
  			return ONENAND_BBT_READ_ECC_ERROR;
  		}
  	} else {
  		printk(KERN_ERR "%s: read timeout! ctrl 0x%04x "
  		       "intr 0x%04x addr1 %#x addr8 %#x\n",
  		       __func__, ctrl, interrupt, addr1, addr8);
  		return ONENAND_BBT_READ_FATAL_ERROR;
  	}
  
  	/* Initial bad block case: 0x2400 or 0x0400 */
  	if (ctrl & ONENAND_CTRL_ERROR) {
  		printk(KERN_DEBUG "%s: ctrl 0x%04x intr 0x%04x addr1 %#x "
  		       "addr8 %#x\n", __func__, ctrl, interrupt, addr1, addr8);
  		return ONENAND_BBT_READ_ERROR;
  	}
  
  	return 0;
  }
  
  /**
   * onenand_bbt_read_oob - [MTD Interface] OneNAND read out-of-band for bbt scan
   * @param mtd		MTD device structure
   * @param from		offset to read from
   * @param ops		oob operation description structure
   *
   * OneNAND read out-of-band data from the spare area for bbt scan
   */
  int onenand_bbt_read_oob(struct mtd_info *mtd, loff_t from, 
  			    struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	int read = 0, thislen, column;
  	int ret = 0, readcmd;
  	size_t len = ops->ooblen;
  	u_char *buf = ops->oobbuf;
  
  	pr_debug("%s: from = 0x%08x, len = %zi\n", __func__, (unsigned int)from,
  			len);
  
  	/* Initialize return value */
  	ops->oobretlen = 0;
  
  	/* Do not allow reads past end of device */
  	if (unlikely((from + len) > mtd->size)) {
  		printk(KERN_ERR "%s: Attempt read beyond end of device\n",
  			__func__);
  		return ONENAND_BBT_READ_FATAL_ERROR;
  	}
  
  	/* Grab the lock and see if the device is available */
  	onenand_get_device(mtd, FL_READING);
  
  	column = from & (mtd->oobsize - 1);
  
  	readcmd = ONENAND_IS_4KB_PAGE(this) ? ONENAND_CMD_READ : ONENAND_CMD_READOOB;
  
  	while (read < len) {
  		cond_resched();
  
  		thislen = mtd->oobsize - column;
  		thislen = min_t(int, thislen, len);
  
  		this->command(mtd, readcmd, from, mtd->oobsize);
  
  		onenand_update_bufferram(mtd, from, 0);
  
  		ret = this->bbt_wait(mtd, FL_READING);
  		if (unlikely(ret))
  			ret = onenand_recover_lsb(mtd, from, ret);
  
  		if (ret)
  			break;
  
  		this->read_bufferram(mtd, ONENAND_SPARERAM, buf, column, thislen);
  		read += thislen;
  		if (read == len)
  			break;
  
  		buf += thislen;
  
  		/* Read more? */
  		if (read < len) {
  			/* Update Page size */
  			from += this->writesize;
  			column = 0;
  		}
  	}
  
  	/* Deselect and wake up anyone waiting on the device */
  	onenand_release_device(mtd);
  
  	ops->oobretlen = read;
  	return ret;
  }
  
  #ifdef CONFIG_MTD_ONENAND_VERIFY_WRITE
  /**
   * onenand_verify_oob - [GENERIC] verify the oob contents after a write
   * @param mtd		MTD device structure
   * @param buf		the databuffer to verify
   * @param to		offset to read from
   */
  static int onenand_verify_oob(struct mtd_info *mtd, const u_char *buf, loff_t to)
  {
  	struct onenand_chip *this = mtd->priv;
  	u_char *oob_buf = this->oob_buf;
  	int status, i, readcmd;
  
  	readcmd = ONENAND_IS_4KB_PAGE(this) ? ONENAND_CMD_READ : ONENAND_CMD_READOOB;
  
  	this->command(mtd, readcmd, to, mtd->oobsize);
  	onenand_update_bufferram(mtd, to, 0);
  	status = this->wait(mtd, FL_READING);
  	if (status)
  		return status;
  
  	this->read_bufferram(mtd, ONENAND_SPARERAM, oob_buf, 0, mtd->oobsize);
  	for (i = 0; i < mtd->oobsize; i++)
  		if (buf[i] != 0xFF && buf[i] != oob_buf[i])
  			return -EBADMSG;
  
  	return 0;
  }
  
  /**
   * onenand_verify - [GENERIC] verify the chip contents after a write
   * @param mtd          MTD device structure
   * @param buf          the databuffer to verify
   * @param addr         offset to read from
   * @param len          number of bytes to read and compare
   */
  static int onenand_verify(struct mtd_info *mtd, const u_char *buf, loff_t addr, size_t len)
  {
  	struct onenand_chip *this = mtd->priv;
  	int ret = 0;
  	int thislen, column;
  
  	column = addr & (this->writesize - 1);
  
  	while (len != 0) {
  		thislen = min_t(int, this->writesize - column, len);
  
  		this->command(mtd, ONENAND_CMD_READ, addr, this->writesize);
  
  		onenand_update_bufferram(mtd, addr, 0);
  
  		ret = this->wait(mtd, FL_READING);
  		if (ret)
  			return ret;
  
  		onenand_update_bufferram(mtd, addr, 1);
  
  		this->read_bufferram(mtd, ONENAND_DATARAM, this->verify_buf, 0, mtd->writesize);
  
  		if (memcmp(buf, this->verify_buf + column, thislen))
  			return -EBADMSG;
  
  		len -= thislen;
  		buf += thislen;
  		addr += thislen;
  		column = 0;
  	}
  
  	return 0;
  }
  #else
  #define onenand_verify(...)		(0)
  #define onenand_verify_oob(...)		(0)
  #endif
  
  #define NOTALIGNED(x)	((x & (this->subpagesize - 1)) != 0)
  
  static void onenand_panic_wait(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	unsigned int interrupt;
  	int i;
  	
  	for (i = 0; i < 2000; i++) {
  		interrupt = this->read_word(this->base + ONENAND_REG_INTERRUPT);
  		if (interrupt & ONENAND_INT_MASTER)
  			break;
  		udelay(10);
  	}
  }
  
  /**
   * onenand_panic_write - [MTD Interface] write buffer to FLASH in a panic context
   * @param mtd		MTD device structure
   * @param to		offset to write to
   * @param len		number of bytes to write
   * @param retlen	pointer to variable to store the number of written bytes
   * @param buf		the data to write
   *
   * Write with ECC
   */
  static int onenand_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
  			 size_t *retlen, const u_char *buf)
  {
  	struct onenand_chip *this = mtd->priv;
  	int column, subpage;
  	int written = 0;
  	int ret = 0;
  
  	if (this->state == FL_PM_SUSPENDED)
  		return -EBUSY;
  
  	/* Wait for any existing operation to clear */
  	onenand_panic_wait(mtd);
  
  	pr_debug("%s: to = 0x%08x, len = %i\n", __func__, (unsigned int)to,
  			(int)len);
  
  	/* Reject writes, which are not page aligned */
          if (unlikely(NOTALIGNED(to) || NOTALIGNED(len))) {
  		printk(KERN_ERR "%s: Attempt to write not page aligned data\n",
  			__func__);
                  return -EINVAL;
          }
  
  	column = to & (mtd->writesize - 1);
  
  	/* Loop until all data write */
  	while (written < len) {
  		int thislen = min_t(int, mtd->writesize - column, len - written);
  		u_char *wbuf = (u_char *) buf;
  
  		this->command(mtd, ONENAND_CMD_BUFFERRAM, to, thislen);
  
  		/* Partial page write */
  		subpage = thislen < mtd->writesize;
  		if (subpage) {
  			memset(this->page_buf, 0xff, mtd->writesize);
  			memcpy(this->page_buf + column, buf, thislen);
  			wbuf = this->page_buf;
  		}
  
  		this->write_bufferram(mtd, ONENAND_DATARAM, wbuf, 0, mtd->writesize);
  		this->write_bufferram(mtd, ONENAND_SPARERAM, ffchars, 0, mtd->oobsize);
  
  		this->command(mtd, ONENAND_CMD_PROG, to, mtd->writesize);
  
  		onenand_panic_wait(mtd);
  
  		/* In partial page write we don't update bufferram */
  		onenand_update_bufferram(mtd, to, !ret && !subpage);
  		if (ONENAND_IS_2PLANE(this)) {
  			ONENAND_SET_BUFFERRAM1(this);
  			onenand_update_bufferram(mtd, to + this->writesize, !ret && !subpage);
  		}
  
  		if (ret) {
  			printk(KERN_ERR "%s: write failed %d\n", __func__, ret);
  			break;
  		}
  
  		written += thislen;
  
  		if (written == len)
  			break;
  
  		column = 0;
  		to += thislen;
  		buf += thislen;
  	}
  
  	*retlen = written;
  	return ret;
  }
  
  /**
   * onenand_fill_auto_oob - [INTERN] oob auto-placement transfer
   * @param mtd		MTD device structure
   * @param oob_buf	oob buffer
   * @param buf		source address
   * @param column	oob offset to write to
   * @param thislen	oob length to write
   */
  static int onenand_fill_auto_oob(struct mtd_info *mtd, u_char *oob_buf,
  				  const u_char *buf, int column, int thislen)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct nand_oobfree *free;
  	int writecol = column;
  	int writeend = column + thislen;
  	int lastgap = 0;
  	unsigned int i;
  
  	free = this->ecclayout->oobfree;
  	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES && free->length; i++, free++) {
  		if (writecol >= lastgap)
  			writecol += free->offset - lastgap;
  		if (writeend >= lastgap)
  			writeend += free->offset - lastgap;
  		lastgap = free->offset + free->length;
  	}
  	free = this->ecclayout->oobfree;
  	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES && free->length; i++, free++) {
  		int free_end = free->offset + free->length;
  		if (free->offset < writeend && free_end > writecol) {
  			int st = max_t(int,free->offset,writecol);
  			int ed = min_t(int,free_end,writeend);
  			int n = ed - st;
  			memcpy(oob_buf + st, buf, n);
  			buf += n;
  		} else if (column == 0)
  			break;
  	}
  	return 0;
  }
  
  /**
   * onenand_write_ops_nolock - [OneNAND Interface] write main and/or out-of-band
   * @param mtd		MTD device structure
   * @param to		offset to write to
   * @param ops		oob operation description structure
   *
   * Write main and/or oob with ECC
   */
  static int onenand_write_ops_nolock(struct mtd_info *mtd, loff_t to,
  				struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	int written = 0, column, thislen = 0, subpage = 0;
  	int prev = 0, prevlen = 0, prev_subpage = 0, first = 1;
  	int oobwritten = 0, oobcolumn, thisooblen, oobsize;
  	size_t len = ops->len;
  	size_t ooblen = ops->ooblen;
  	const u_char *buf = ops->datbuf;
  	const u_char *oob = ops->oobbuf;
  	u_char *oobbuf;
  	int ret = 0, cmd;
  
  	pr_debug("%s: to = 0x%08x, len = %i\n", __func__, (unsigned int)to,
  			(int)len);
  
  	/* Initialize retlen, in case of early exit */
  	ops->retlen = 0;
  	ops->oobretlen = 0;
  
  	/* Reject writes, which are not page aligned */
          if (unlikely(NOTALIGNED(to) || NOTALIGNED(len))) {
  		printk(KERN_ERR "%s: Attempt to write not page aligned data\n",
  			__func__);
                  return -EINVAL;
          }
  
  	/* Check zero length */
  	if (!len)
  		return 0;
  
  	if (ops->mode == MTD_OPS_AUTO_OOB)
  		oobsize = this->ecclayout->oobavail;
  	else
  		oobsize = mtd->oobsize;
  
  	oobcolumn = to & (mtd->oobsize - 1);
  
  	column = to & (mtd->writesize - 1);
  
  	/* Loop until all data write */
  	while (1) {
  		if (written < len) {
  			u_char *wbuf = (u_char *) buf;
  
  			thislen = min_t(int, mtd->writesize - column, len - written);
  			thisooblen = min_t(int, oobsize - oobcolumn, ooblen - oobwritten);
  
  			cond_resched();
  
  			this->command(mtd, ONENAND_CMD_BUFFERRAM, to, thislen);
  
  			/* Partial page write */
  			subpage = thislen < mtd->writesize;
  			if (subpage) {
  				memset(this->page_buf, 0xff, mtd->writesize);
  				memcpy(this->page_buf + column, buf, thislen);
  				wbuf = this->page_buf;
  			}
  
  			this->write_bufferram(mtd, ONENAND_DATARAM, wbuf, 0, mtd->writesize);
  
  			if (oob) {
  				oobbuf = this->oob_buf;
  
  				/* We send data to spare ram with oobsize
  				 * to prevent byte access */
  				memset(oobbuf, 0xff, mtd->oobsize);
  				if (ops->mode == MTD_OPS_AUTO_OOB)
  					onenand_fill_auto_oob(mtd, oobbuf, oob, oobcolumn, thisooblen);
  				else
  					memcpy(oobbuf + oobcolumn, oob, thisooblen);
  
  				oobwritten += thisooblen;
  				oob += thisooblen;
  				oobcolumn = 0;
  			} else
  				oobbuf = (u_char *) ffchars;
  
  			this->write_bufferram(mtd, ONENAND_SPARERAM, oobbuf, 0, mtd->oobsize);
  		} else
  			ONENAND_SET_NEXT_BUFFERRAM(this);
  
  		/*
  		 * 2 PLANE, MLC, and Flex-OneNAND do not support
  		 * write-while-program feature.
  		 */
  		if (!ONENAND_IS_2PLANE(this) && !ONENAND_IS_4KB_PAGE(this) && !first) {
  			ONENAND_SET_PREV_BUFFERRAM(this);
  
  			ret = this->wait(mtd, FL_WRITING);
  
  			/* In partial page write we don't update bufferram */
  			onenand_update_bufferram(mtd, prev, !ret && !prev_subpage);
  			if (ret) {
  				written -= prevlen;
  				printk(KERN_ERR "%s: write failed %d\n",
  					__func__, ret);
  				break;
  			}
  
  			if (written == len) {
  				/* Only check verify write turn on */
  				ret = onenand_verify(mtd, buf - len, to - len, len);
  				if (ret)
  					printk(KERN_ERR "%s: verify failed %d\n",
  						__func__, ret);
  				break;
  			}
  
  			ONENAND_SET_NEXT_BUFFERRAM(this);
  		}
  
  		this->ongoing = 0;
  		cmd = ONENAND_CMD_PROG;
  
  		/* Exclude 1st OTP and OTP blocks for cache program feature */
  		if (ONENAND_IS_CACHE_PROGRAM(this) &&
  		    likely(onenand_block(this, to) != 0) &&
  		    ONENAND_IS_4KB_PAGE(this) &&
  		    ((written + thislen) < len)) {
  			cmd = ONENAND_CMD_2X_CACHE_PROG;
  			this->ongoing = 1;
  		}
  
  		this->command(mtd, cmd, to, mtd->writesize);
  
  		/*
  		 * 2 PLANE, MLC, and Flex-OneNAND wait here
  		 */
  		if (ONENAND_IS_2PLANE(this) || ONENAND_IS_4KB_PAGE(this)) {
  			ret = this->wait(mtd, FL_WRITING);
  
  			/* In partial page write we don't update bufferram */
  			onenand_update_bufferram(mtd, to, !ret && !subpage);
  			if (ret) {
  				printk(KERN_ERR "%s: write failed %d\n",
  					__func__, ret);
  				break;
  			}
  
  			/* Only check verify write turn on */
  			ret = onenand_verify(mtd, buf, to, thislen);
  			if (ret) {
  				printk(KERN_ERR "%s: verify failed %d\n",
  					__func__, ret);
  				break;
  			}
  
  			written += thislen;
  
  			if (written == len)
  				break;
  
  		} else
  			written += thislen;
  
  		column = 0;
  		prev_subpage = subpage;
  		prev = to;
  		prevlen = thislen;
  		to += thislen;
  		buf += thislen;
  		first = 0;
  	}
  
  	/* In error case, clear all bufferrams */
  	if (written != len)
  		onenand_invalidate_bufferram(mtd, 0, -1);
  
  	ops->retlen = written;
  	ops->oobretlen = oobwritten;
  
  	return ret;
  }
  
  
  /**
   * onenand_write_oob_nolock - [INTERN] OneNAND write out-of-band
   * @param mtd		MTD device structure
   * @param to		offset to write to
   * @param len		number of bytes to write
   * @param retlen	pointer to variable to store the number of written bytes
   * @param buf		the data to write
   * @param mode		operation mode
   *
   * OneNAND write out-of-band
   */
  static int onenand_write_oob_nolock(struct mtd_info *mtd, loff_t to,
  				    struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	int column, ret = 0, oobsize;
  	int written = 0, oobcmd;
  	u_char *oobbuf;
  	size_t len = ops->ooblen;
  	const u_char *buf = ops->oobbuf;
  	unsigned int mode = ops->mode;
  
  	to += ops->ooboffs;
  
  	pr_debug("%s: to = 0x%08x, len = %i\n", __func__, (unsigned int)to,
  			(int)len);
  
  	/* Initialize retlen, in case of early exit */
  	ops->oobretlen = 0;
  
  	if (mode == MTD_OPS_AUTO_OOB)
  		oobsize = this->ecclayout->oobavail;
  	else
  		oobsize = mtd->oobsize;
  
  	column = to & (mtd->oobsize - 1);
  
  	if (unlikely(column >= oobsize)) {
  		printk(KERN_ERR "%s: Attempted to start write outside oob\n",
  			__func__);
  		return -EINVAL;
  	}
  
  	/* For compatibility with NAND: Do not allow write past end of page */
  	if (unlikely(column + len > oobsize)) {
  		printk(KERN_ERR "%s: Attempt to write past end of page\n",
  			__func__);
  		return -EINVAL;
  	}
  
  	/* Do not allow reads past end of device */
  	if (unlikely(to >= mtd->size ||
  		     column + len > ((mtd->size >> this->page_shift) -
  				     (to >> this->page_shift)) * oobsize)) {
  		printk(KERN_ERR "%s: Attempted to write past end of device\n",
  		       __func__);
  		return -EINVAL;
  	}
  
  	oobbuf = this->oob_buf;
  
  	oobcmd = ONENAND_IS_4KB_PAGE(this) ? ONENAND_CMD_PROG : ONENAND_CMD_PROGOOB;
  
  	/* Loop until all data write */
  	while (written < len) {
  		int thislen = min_t(int, oobsize, len - written);
  
  		cond_resched();
  
  		this->command(mtd, ONENAND_CMD_BUFFERRAM, to, mtd->oobsize);
  
  		/* We send data to spare ram with oobsize
  		 * to prevent byte access */
  		memset(oobbuf, 0xff, mtd->oobsize);
  		if (mode == MTD_OPS_AUTO_OOB)
  			onenand_fill_auto_oob(mtd, oobbuf, buf, column, thislen);
  		else
  			memcpy(oobbuf + column, buf, thislen);
  		this->write_bufferram(mtd, ONENAND_SPARERAM, oobbuf, 0, mtd->oobsize);
  
  		if (ONENAND_IS_4KB_PAGE(this)) {
  			/* Set main area of DataRAM to 0xff*/
  			memset(this->page_buf, 0xff, mtd->writesize);
  			this->write_bufferram(mtd, ONENAND_DATARAM,
  					 this->page_buf, 0, mtd->writesize);
  		}
  
  		this->command(mtd, oobcmd, to, mtd->oobsize);
  
  		onenand_update_bufferram(mtd, to, 0);
  		if (ONENAND_IS_2PLANE(this)) {
  			ONENAND_SET_BUFFERRAM1(this);
  			onenand_update_bufferram(mtd, to + this->writesize, 0);
  		}
  
  		ret = this->wait(mtd, FL_WRITING);
  		if (ret) {
  			printk(KERN_ERR "%s: write failed %d\n", __func__, ret);
  			break;
  		}
  
  		ret = onenand_verify_oob(mtd, oobbuf, to);
  		if (ret) {
  			printk(KERN_ERR "%s: verify failed %d\n",
  				__func__, ret);
  			break;
  		}
  
  		written += thislen;
  		if (written == len)
  			break;
  
  		to += mtd->writesize;
  		buf += thislen;
  		column = 0;
  	}
  
  	ops->oobretlen = written;
  
  	return ret;
  }
  
  /**
   * onenand_write - [MTD Interface] write buffer to FLASH
   * @param mtd		MTD device structure
   * @param to		offset to write to
   * @param len		number of bytes to write
   * @param retlen	pointer to variable to store the number of written bytes
   * @param buf		the data to write
   *
   * Write with ECC
   */
  static int onenand_write(struct mtd_info *mtd, loff_t to, size_t len,
  	size_t *retlen, const u_char *buf)
  {
  	struct mtd_oob_ops ops = {
  		.len	= len,
  		.ooblen	= 0,
  		.datbuf	= (u_char *) buf,
  		.oobbuf	= NULL,
  	};
  	int ret;
  
  	onenand_get_device(mtd, FL_WRITING);
  	ret = onenand_write_ops_nolock(mtd, to, &ops);
  	onenand_release_device(mtd);
  
  	*retlen = ops.retlen;
  	return ret;
  }
  
  /**
   * onenand_write_oob - [MTD Interface] NAND write data and/or out-of-band
   * @param mtd:		MTD device structure
   * @param to:		offset to write
   * @param ops:		oob operation description structure
   */
  static int onenand_write_oob(struct mtd_info *mtd, loff_t to,
  			     struct mtd_oob_ops *ops)
  {
  	int ret;
  
  	switch (ops->mode) {
  	case MTD_OPS_PLACE_OOB:
  	case MTD_OPS_AUTO_OOB:
  		break;
  	case MTD_OPS_RAW:
  		/* Not implemented yet */
  	default:
  		return -EINVAL;
  	}
  
  	onenand_get_device(mtd, FL_WRITING);
  	if (ops->datbuf)
  		ret = onenand_write_ops_nolock(mtd, to, ops);
  	else
  		ret = onenand_write_oob_nolock(mtd, to, ops);
  	onenand_release_device(mtd);
  
  	return ret;
  }
  
  /**
   * onenand_block_isbad_nolock - [GENERIC] Check if a block is marked bad
   * @param mtd		MTD device structure
   * @param ofs		offset from device start
   * @param 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 onenand_block_isbad_nolock(struct mtd_info *mtd, loff_t ofs, int allowbbt)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct bbm_info *bbm = this->bbm;
  
  	/* Return info from the table */
  	return bbm->isbad_bbt(mtd, ofs, allowbbt);
  }
  
  
  static int onenand_multiblock_erase_verify(struct mtd_info *mtd,
  					   struct erase_info *instr)
  {
  	struct onenand_chip *this = mtd->priv;
  	loff_t addr = instr->addr;
  	int len = instr->len;
  	unsigned int block_size = (1 << this->erase_shift);
  	int ret = 0;
  
  	while (len) {
  		this->command(mtd, ONENAND_CMD_ERASE_VERIFY, addr, block_size);
  		ret = this->wait(mtd, FL_VERIFYING_ERASE);
  		if (ret) {
  			printk(KERN_ERR "%s: Failed verify, block %d\n",
  			       __func__, onenand_block(this, addr));
  			instr->state = MTD_ERASE_FAILED;
  			instr->fail_addr = addr;
  			return -1;
  		}
  		len -= block_size;
  		addr += block_size;
  	}
  	return 0;
  }
  
  /**
   * onenand_multiblock_erase - [INTERN] erase block(s) using multiblock erase
   * @param mtd		MTD device structure
   * @param instr		erase instruction
   * @param region	erase region
   *
   * Erase one or more blocks up to 64 block at a time
   */
  static int onenand_multiblock_erase(struct mtd_info *mtd,
  				    struct erase_info *instr,
  				    unsigned int block_size)
  {
  	struct onenand_chip *this = mtd->priv;
  	loff_t addr = instr->addr;
  	int len = instr->len;
  	int eb_count = 0;
  	int ret = 0;
  	int bdry_block = 0;
  
  	instr->state = MTD_ERASING;
  
  	if (ONENAND_IS_DDP(this)) {
  		loff_t bdry_addr = this->chipsize >> 1;
  		if (addr < bdry_addr && (addr + len) > bdry_addr)
  			bdry_block = bdry_addr >> this->erase_shift;
  	}
  
  	/* Pre-check bbs */
  	while (len) {
  		/* Check if we have a bad block, we do not erase bad blocks */
  		if (onenand_block_isbad_nolock(mtd, addr, 0)) {
  			printk(KERN_WARNING "%s: attempt to erase a bad block "
  			       "at addr 0x%012llx\n",
  			       __func__, (unsigned long long) addr);
  			instr->state = MTD_ERASE_FAILED;
  			return -EIO;
  		}
  		len -= block_size;
  		addr += block_size;
  	}
  
  	len = instr->len;
  	addr = instr->addr;
  
  	/* loop over 64 eb batches */
  	while (len) {
  		struct erase_info verify_instr = *instr;
  		int max_eb_count = MB_ERASE_MAX_BLK_COUNT;
  
  		verify_instr.addr = addr;
  		verify_instr.len = 0;
  
  		/* do not cross chip boundary */
  		if (bdry_block) {
  			int this_block = (addr >> this->erase_shift);
  
  			if (this_block < bdry_block) {
  				max_eb_count = min(max_eb_count,
  						   (bdry_block - this_block));
  			}
  		}
  
  		eb_count = 0;
  
  		while (len > block_size && eb_count < (max_eb_count - 1)) {
  			this->command(mtd, ONENAND_CMD_MULTIBLOCK_ERASE,
  				      addr, block_size);
  			onenand_invalidate_bufferram(mtd, addr, block_size);
  
  			ret = this->wait(mtd, FL_PREPARING_ERASE);
  			if (ret) {
  				printk(KERN_ERR "%s: Failed multiblock erase, "
  				       "block %d\n", __func__,
  				       onenand_block(this, addr));
  				instr->state = MTD_ERASE_FAILED;
  				instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
  				return -EIO;
  			}
  
  			len -= block_size;
  			addr += block_size;
  			eb_count++;
  		}
  
  		/* last block of 64-eb series */
  		cond_resched();
  		this->command(mtd, ONENAND_CMD_ERASE, addr, block_size);
  		onenand_invalidate_bufferram(mtd, addr, block_size);
  
  		ret = this->wait(mtd, FL_ERASING);
  		/* Check if it is write protected */
  		if (ret) {
  			printk(KERN_ERR "%s: Failed erase, block %d\n",
  			       __func__, onenand_block(this, addr));
  			instr->state = MTD_ERASE_FAILED;
  			instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
  			return -EIO;
  		}
  
  		len -= block_size;
  		addr += block_size;
  		eb_count++;
  
  		/* verify */
  		verify_instr.len = eb_count * block_size;
  		if (onenand_multiblock_erase_verify(mtd, &verify_instr)) {
  			instr->state = verify_instr.state;
  			instr->fail_addr = verify_instr.fail_addr;
  			return -EIO;
  		}
  
  	}
  	return 0;
  }
  
  
  /**
   * onenand_block_by_block_erase - [INTERN] erase block(s) using regular erase
   * @param mtd		MTD device structure
   * @param instr		erase instruction
   * @param region	erase region
   * @param block_size	erase block size
   *
   * Erase one or more blocks one block at a time
   */
  static int onenand_block_by_block_erase(struct mtd_info *mtd,
  					struct erase_info *instr,
  					struct mtd_erase_region_info *region,
  					unsigned int block_size)
  {
  	struct onenand_chip *this = mtd->priv;
  	loff_t addr = instr->addr;
  	int len = instr->len;
  	loff_t region_end = 0;
  	int ret = 0;
  
  	if (region) {
  		/* region is set for Flex-OneNAND */
  		region_end = region->offset + region->erasesize * region->numblocks;
  	}
  
  	instr->state = MTD_ERASING;
  
  	/* Loop through the blocks */
  	while (len) {
  		cond_resched();
  
  		/* Check if we have a bad block, we do not erase bad blocks */
  		if (onenand_block_isbad_nolock(mtd, addr, 0)) {
  			printk(KERN_WARNING "%s: attempt to erase a bad block "
  					"at addr 0x%012llx\n",
  					__func__, (unsigned long long) addr);
  			instr->state = MTD_ERASE_FAILED;
  			return -EIO;
  		}
  
  		this->command(mtd, ONENAND_CMD_ERASE, addr, block_size);
  
  		onenand_invalidate_bufferram(mtd, addr, block_size);
  
  		ret = this->wait(mtd, FL_ERASING);
  		/* Check, if it is write protected */
  		if (ret) {
  			printk(KERN_ERR "%s: Failed erase, block %d\n",
  				__func__, onenand_block(this, addr));
  			instr->state = MTD_ERASE_FAILED;
  			instr->fail_addr = addr;
  			return -EIO;
  		}
  
  		len -= block_size;
  		addr += block_size;
  
  		if (region && addr == region_end) {
  			if (!len)
  				break;
  			region++;
  
  			block_size = region->erasesize;
  			region_end = region->offset + region->erasesize * region->numblocks;
  
  			if (len & (block_size - 1)) {
  				/* FIXME: This should be handled at MTD partitioning level. */
  				printk(KERN_ERR "%s: Unaligned address\n",
  					__func__);
  				return -EIO;
  			}
  		}
  	}
  	return 0;
  }
  
  /**
   * onenand_erase - [MTD Interface] erase block(s)
   * @param mtd		MTD device structure
   * @param instr		erase instruction
   *
   * Erase one or more blocks
   */
  static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
  {
  	struct onenand_chip *this = mtd->priv;
  	unsigned int block_size;
  	loff_t addr = instr->addr;
  	loff_t len = instr->len;
  	int ret = 0;
  	struct mtd_erase_region_info *region = NULL;
  	loff_t region_offset = 0;
  
  	pr_debug("%s: start=0x%012llx, len=%llu\n", __func__,
  			(unsigned long long)instr->addr,
  			(unsigned long long)instr->len);
  
  	if (FLEXONENAND(this)) {
  		/* Find the eraseregion of this address */
  		int i = flexonenand_region(mtd, addr);
  
  		region = &mtd->eraseregions[i];
  		block_size = region->erasesize;
  
  		/* Start address within region must align on block boundary.
  		 * Erase region's start offset is always block start address.
  		 */
  		region_offset = region->offset;
  	} else
  		block_size = 1 << this->erase_shift;
  
  	/* Start address must align on block boundary */
  	if (unlikely((addr - region_offset) & (block_size - 1))) {
  		printk(KERN_ERR "%s: Unaligned address\n", __func__);
  		return -EINVAL;
  	}
  
  	/* Length must align on block boundary */
  	if (unlikely(len & (block_size - 1))) {
  		printk(KERN_ERR "%s: Length not block aligned\n", __func__);
  		return -EINVAL;
  	}
  
  	/* Grab the lock and see if the device is available */
  	onenand_get_device(mtd, FL_ERASING);
  
  	if (ONENAND_IS_4KB_PAGE(this) || region ||
  	    instr->len < MB_ERASE_MIN_BLK_COUNT * block_size) {
  		/* region is set for Flex-OneNAND (no mb erase) */
  		ret = onenand_block_by_block_erase(mtd, instr,
  						   region, block_size);
  	} else {
  		ret = onenand_multiblock_erase(mtd, instr, block_size);
  	}
  
  	/* Deselect and wake up anyone waiting on the device */
  	onenand_release_device(mtd);
  
  	/* Do call back function */
  	if (!ret) {
  		instr->state = MTD_ERASE_DONE;
  		mtd_erase_callback(instr);
  	}
  
  	return ret;
  }
  
  /**
   * onenand_sync - [MTD Interface] sync
   * @param mtd		MTD device structure
   *
   * Sync is actually a wait for chip ready function
   */
  static void onenand_sync(struct mtd_info *mtd)
  {
  	pr_debug("%s: called\n", __func__);
  
  	/* Grab the lock and see if the device is available */
  	onenand_get_device(mtd, FL_SYNCING);
  
  	/* Release it and go back */
  	onenand_release_device(mtd);
  }
  
  /**
   * onenand_block_isbad - [MTD Interface] Check whether the block at the given offset is bad
   * @param mtd		MTD device structure
   * @param ofs		offset relative to mtd start
   *
   * Check whether the block is bad
   */
  static int onenand_block_isbad(struct mtd_info *mtd, loff_t ofs)
  {
  	int ret;
  
  	/* Check for invalid offset */
  	if (ofs > mtd->size)
  		return -EINVAL;
  
  	onenand_get_device(mtd, FL_READING);
  	ret = onenand_block_isbad_nolock(mtd, ofs, 0);
  	onenand_release_device(mtd);
  	return ret;
  }
  
  /**
   * onenand_default_block_markbad - [DEFAULT] mark a block bad
   * @param mtd		MTD device structure
   * @param ofs		offset from device start
   *
   * This is the default implementation, which can be overridden by
   * a hardware specific driver.
   */
  static int onenand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct bbm_info *bbm = this->bbm;
  	u_char buf[2] = {0, 0};
  	struct mtd_oob_ops ops = {
  		.mode = MTD_OPS_PLACE_OOB,
  		.ooblen = 2,
  		.oobbuf = buf,
  		.ooboffs = 0,
  	};
  	int block;
  
  	/* Get block number */
  	block = onenand_block(this, ofs);
          if (bbm->bbt)
                  bbm->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
  
          /* We write two bytes, so we don't have to mess with 16-bit access */
          ofs += mtd->oobsize + (bbm->badblockpos & ~0x01);
  	/* FIXME : What to do when marking SLC block in partition
  	 * 	   with MLC erasesize? For now, it is not advisable to
  	 *	   create partitions containing both SLC and MLC regions.
  	 */
  	return onenand_write_oob_nolock(mtd, ofs, &ops);
  }
  
  /**
   * onenand_block_markbad - [MTD Interface] Mark the block at the given offset as bad
   * @param mtd		MTD device structure
   * @param ofs		offset relative to mtd start
   *
   * Mark the block as bad
   */
  static int onenand_block_markbad(struct mtd_info *mtd, loff_t ofs)
  {
  	struct onenand_chip *this = mtd->priv;
  	int ret;
  
  	ret = onenand_block_isbad(mtd, ofs);
  	if (ret) {
  		/* If it was bad already, return success and do nothing */
  		if (ret > 0)
  			return 0;
  		return ret;
  	}
  
  	onenand_get_device(mtd, FL_WRITING);
  	ret = this->block_markbad(mtd, ofs);
  	onenand_release_device(mtd);
  	return ret;
  }
  
  /**
   * onenand_do_lock_cmd - [OneNAND Interface] Lock or unlock block(s)
   * @param mtd		MTD device structure
   * @param ofs		offset relative to mtd start
   * @param len		number of bytes to lock or unlock
   * @param cmd		lock or unlock command
   *
   * Lock or unlock one or more blocks
   */
  static int onenand_do_lock_cmd(struct mtd_info *mtd, loff_t ofs, size_t len, int cmd)
  {
  	struct onenand_chip *this = mtd->priv;
  	int start, end, block, value, status;
  	int wp_status_mask;
  
  	start = onenand_block(this, ofs);
  	end = onenand_block(this, ofs + len) - 1;
  
  	if (cmd == ONENAND_CMD_LOCK)
  		wp_status_mask = ONENAND_WP_LS;
  	else
  		wp_status_mask = ONENAND_WP_US;
  
  	/* Continuous lock scheme */
  	if (this->options & ONENAND_HAS_CONT_LOCK) {
  		/* Set start block address */
  		this->write_word(start, this->base + ONENAND_REG_START_BLOCK_ADDRESS);
  		/* Set end block address */
  		this->write_word(end, this->base +  ONENAND_REG_END_BLOCK_ADDRESS);
  		/* Write lock command */
  		this->command(mtd, cmd, 0, 0);
  
  		/* There's no return value */
  		this->wait(mtd, FL_LOCKING);
  
  		/* Sanity check */
  		while (this->read_word(this->base + ONENAND_REG_CTRL_STATUS)
  		    & ONENAND_CTRL_ONGO)
  			continue;
  
  		/* Check lock status */
  		status = this->read_word(this->base + ONENAND_REG_WP_STATUS);
  		if (!(status & wp_status_mask))
  			printk(KERN_ERR "%s: wp status = 0x%x\n",
  				__func__, status);
  
  		return 0;
  	}
  
  	/* Block lock scheme */
  	for (block = start; block < end + 1; block++) {
  		/* Set block address */
  		value = onenand_block_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
  		/* Select DataRAM for DDP */
  		value = onenand_bufferram_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
  		/* Set start block address */
  		this->write_word(block, this->base + ONENAND_REG_START_BLOCK_ADDRESS);
  		/* Write lock command */
  		this->command(mtd, cmd, 0, 0);
  
  		/* There's no return value */
  		this->wait(mtd, FL_LOCKING);
  
  		/* Sanity check */
  		while (this->read_word(this->base + ONENAND_REG_CTRL_STATUS)
  		    & ONENAND_CTRL_ONGO)
  			continue;
  
  		/* Check lock status */
  		status = this->read_word(this->base + ONENAND_REG_WP_STATUS);
  		if (!(status & wp_status_mask))
  			printk(KERN_ERR "%s: block = %d, wp status = 0x%x\n",
  				__func__, block, status);
  	}
  
  	return 0;
  }
  
  /**
   * onenand_lock - [MTD Interface] Lock block(s)
   * @param mtd		MTD device structure
   * @param ofs		offset relative to mtd start
   * @param len		number of bytes to unlock
   *
   * Lock one or more blocks
   */
  static int onenand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
  {
  	int ret;
  
  	onenand_get_device(mtd, FL_LOCKING);
  	ret = onenand_do_lock_cmd(mtd, ofs, len, ONENAND_CMD_LOCK);
  	onenand_release_device(mtd);
  	return ret;
  }
  
  /**
   * onenand_unlock - [MTD Interface] Unlock block(s)
   * @param mtd		MTD device structure
   * @param ofs		offset relative to mtd start
   * @param len		number of bytes to unlock
   *
   * Unlock one or more blocks
   */
  static int onenand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
  {
  	int ret;
  
  	onenand_get_device(mtd, FL_LOCKING);
  	ret = onenand_do_lock_cmd(mtd, ofs, len, ONENAND_CMD_UNLOCK);
  	onenand_release_device(mtd);
  	return ret;
  }
  
  /**
   * onenand_check_lock_status - [OneNAND Interface] Check lock status
   * @param this		onenand chip data structure
   *
   * Check lock status
   */
  static int onenand_check_lock_status(struct onenand_chip *this)
  {
  	unsigned int value, block, status;
  	unsigned int end;
  
  	end = this->chipsize >> this->erase_shift;
  	for (block = 0; block < end; block++) {
  		/* Set block address */
  		value = onenand_block_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
  		/* Select DataRAM for DDP */
  		value = onenand_bufferram_address(this, block);
  		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
  		/* Set start block address */
  		this->write_word(block, this->base + ONENAND_REG_START_BLOCK_ADDRESS);
  
  		/* Check lock status */
  		status = this->read_word(this->base + ONENAND_REG_WP_STATUS);
  		if (!(status & ONENAND_WP_US)) {
  			printk(KERN_ERR "%s: block = %d, wp status = 0x%x\n",
  				__func__, block, status);
  			return 0;
  		}
  	}
  
  	return 1;
  }
  
  /**
   * onenand_unlock_all - [OneNAND Interface] unlock all blocks
   * @param mtd		MTD device structure
   *
   * Unlock all blocks
   */
  static void onenand_unlock_all(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	loff_t ofs = 0;
  	loff_t len = mtd->size;
  
  	if (this->options & ONENAND_HAS_UNLOCK_ALL) {
  		/* Set start block address */
  		this->write_word(0, this->base + ONENAND_REG_START_BLOCK_ADDRESS);
  		/* Write unlock command */
  		this->command(mtd, ONENAND_CMD_UNLOCK_ALL, 0, 0);
  
  		/* There's no return value */
  		this->wait(mtd, FL_LOCKING);
  
  		/* Sanity check */
  		while (this->read_word(this->base + ONENAND_REG_CTRL_STATUS)
  		    & ONENAND_CTRL_ONGO)
  			continue;
  
  		/* Don't check lock status */
  		if (this->options & ONENAND_SKIP_UNLOCK_CHECK)
  			return;
  
  		/* Check lock status */
  		if (onenand_check_lock_status(this))
  			return;
  
  		/* Workaround for all block unlock in DDP */
  		if (ONENAND_IS_DDP(this) && !FLEXONENAND(this)) {
  			/* All blocks on another chip */
  			ofs = this->chipsize >> 1;
  			len = this->chipsize >> 1;
  		}
  	}
  
  	onenand_do_lock_cmd(mtd, ofs, len, ONENAND_CMD_UNLOCK);
  }
  
  #ifdef CONFIG_MTD_ONENAND_OTP
  
  /**
   * onenand_otp_command - Send OTP specific command to OneNAND device
   * @param mtd	 MTD device structure
   * @param cmd	 the command to be sent
   * @param addr	 offset to read from or write to
   * @param len	 number of bytes to read or write
   */
  static int onenand_otp_command(struct mtd_info *mtd, int cmd, loff_t addr,
  				size_t len)
  {
  	struct onenand_chip *this = mtd->priv;
  	int value, block, page;
  
  	/* Address translation */
  	switch (cmd) {
  	case ONENAND_CMD_OTP_ACCESS:
  		block = (int) (addr >> this->erase_shift);
  		page = -1;
  		break;
  
  	default:
  		block = (int) (addr >> this->erase_shift);
  		page = (int) (addr >> this->page_shift);
  
  		if (ONENAND_IS_2PLANE(this)) {
  			/* Make the even block number */
  			block &= ~1;
  			/* Is it the odd plane? */
  			if (addr & this->writesize)
  				block++;
  			page >>= 1;
  		}
  		page &= this->page_mask;
  		break;
  	}
  
  	if (block != -1) {
  		/* Write 'DFS, FBA' of Flash */
  		value = onenand_block_address(this, block);
  		this->write_word(value, this->base +
  				ONENAND_REG_START_ADDRESS1);
  	}
  
  	if (page != -1) {
  		/* Now we use page size operation */
  		int sectors = 4, count = 4;
  		int dataram;
  
  		switch (cmd) {
  		default:
  			if (ONENAND_IS_2PLANE(this) && cmd == ONENAND_CMD_PROG)
  				cmd = ONENAND_CMD_2X_PROG;
  			dataram = ONENAND_CURRENT_BUFFERRAM(this);
  			break;
  		}
  
  		/* Write 'FPA, FSA' of Flash */
  		value = onenand_page_address(page, sectors);
  		this->write_word(value, this->base +
  				ONENAND_REG_START_ADDRESS8);
  
  		/* Write 'BSA, BSC' of DataRAM */
  		value = onenand_buffer_address(dataram, sectors, count);
  		this->write_word(value, this->base + ONENAND_REG_START_BUFFER);
  	}
  
  	/* Interrupt clear */
  	this->write_word(ONENAND_INT_CLEAR, this->base + ONENAND_REG_INTERRUPT);
  
  	/* Write command */
  	this->write_word(cmd, this->base + ONENAND_REG_COMMAND);
  
  	return 0;
  }
  
  /**
   * onenand_otp_write_oob_nolock - [INTERN] OneNAND write out-of-band, specific to OTP
   * @param mtd		MTD device structure
   * @param to		offset to write to
   * @param len		number of bytes to write
   * @param retlen	pointer to variable to store the number of written bytes
   * @param buf		the data to write
   *
   * OneNAND write out-of-band only for OTP
   */
  static int onenand_otp_write_oob_nolock(struct mtd_info *mtd, loff_t to,
  				    struct mtd_oob_ops *ops)
  {
  	struct onenand_chip *this = mtd->priv;
  	int column, ret = 0, oobsize;
  	int written = 0;
  	u_char *oobbuf;
  	size_t len = ops->ooblen;
  	const u_char *buf = ops->oobbuf;
  	int block, value, status;
  
  	to += ops->ooboffs;
  
  	/* Initialize retlen, in case of early exit */
  	ops->oobretlen = 0;
  
  	oobsize = mtd->oobsize;
  
  	column = to & (mtd->oobsize - 1);
  
  	oobbuf = this->oob_buf;
  
  	/* Loop until all data write */
  	while (written < len) {
  		int thislen = min_t(int, oobsize, len - written);
  
  		cond_resched();
  
  		block = (int) (to >> this->erase_shift);
  		/*
  		 * Write 'DFS, FBA' of Flash
  		 * Add: F100h DQ=DFS, FBA
  		 */
  
  		value = onenand_block_address(this, block);
  		this->write_word(value, this->base +
  				ONENAND_REG_START_ADDRESS1);
  
  		/*
  		 * Select DataRAM for DDP
  		 * Add: F101h DQ=DBS
  		 */
  
  		value = onenand_bufferram_address(this, block);
  		this->write_word(value, this->base +
  				ONENAND_REG_START_ADDRESS2);
  		ONENAND_SET_NEXT_BUFFERRAM(this);
  
  		/*
  		 * Enter OTP access mode
  		 */
  		this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
  		this->wait(mtd, FL_OTPING);
  
  		/* We send data to spare ram with oobsize
  		 * to prevent byte access */
  		memcpy(oobbuf + column, buf, thislen);
  
  		/*
  		 * Write Data into DataRAM
  		 * Add: 8th Word
  		 * in sector0/spare/page0
  		 * DQ=XXFCh
  		 */
  		this->write_bufferram(mtd, ONENAND_SPARERAM,
  					oobbuf, 0, mtd->oobsize);
  
  		onenand_otp_command(mtd, ONENAND_CMD_PROGOOB, to, mtd->oobsize);
  		onenand_update_bufferram(mtd, to, 0);
  		if (ONENAND_IS_2PLANE(this)) {
  			ONENAND_SET_BUFFERRAM1(this);
  			onenand_update_bufferram(mtd, to + this->writesize, 0);
  		}
  
  		ret = this->wait(mtd, FL_WRITING);
  		if (ret) {
  			printk(KERN_ERR "%s: write failed %d\n", __func__, ret);
  			break;
  		}
  
  		/* Exit OTP access mode */
  		this->command(mtd, ONENAND_CMD_RESET, 0, 0);
  		this->wait(mtd, FL_RESETING);
  
  		status = this->read_word(this->base + ONENAND_REG_CTRL_STATUS);
  		status &= 0x60;
  
  		if (status == 0x60) {
  			printk(KERN_DEBUG "\nBLOCK\tSTATUS\n");
  			printk(KERN_DEBUG "1st Block\tLOCKED\n");
  			printk(KERN_DEBUG "OTP Block\tLOCKED\n");
  		} else if (status == 0x20) {
  			printk(KERN_DEBUG "\nBLOCK\tSTATUS\n");
  			printk(KERN_DEBUG "1st Block\tLOCKED\n");
  			printk(KERN_DEBUG "OTP Block\tUN-LOCKED\n");
  		} else if (status == 0x40) {
  			printk(KERN_DEBUG "\nBLOCK\tSTATUS\n");
  			printk(KERN_DEBUG "1st Block\tUN-LOCKED\n");
  			printk(KERN_DEBUG "OTP Block\tLOCKED\n");
  		} else {
  			printk(KERN_DEBUG "Reboot to check\n");
  		}
  
  		written += thislen;
  		if (written == len)
  			break;
  
  		to += mtd->writesize;
  		buf += thislen;
  		column = 0;
  	}
  
  	ops->oobretlen = written;
  
  	return ret;
  }
  
  /* Internal OTP operation */
  typedef int (*otp_op_t)(struct mtd_info *mtd, loff_t form, size_t len,
  		size_t *retlen, u_char *buf);
  
  /**
   * do_otp_read - [DEFAULT] Read OTP block area
   * @param mtd		MTD device structure
   * @param from		The offset to read
   * @param len		number of bytes to read
   * @param retlen	pointer to variable to store the number of readbytes
   * @param buf		the databuffer to put/get data
   *
   * Read OTP block area.
   */
  static int do_otp_read(struct mtd_info *mtd, loff_t from, size_t len,
  		size_t *retlen, u_char *buf)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct mtd_oob_ops ops = {
  		.len	= len,
  		.ooblen	= 0,
  		.datbuf	= buf,
  		.oobbuf	= NULL,
  	};
  	int ret;
  
  	/* Enter OTP access mode */
  	this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
  	this->wait(mtd, FL_OTPING);
  
  	ret = ONENAND_IS_4KB_PAGE(this) ?
  		onenand_mlc_read_ops_nolock(mtd, from, &ops) :
  		onenand_read_ops_nolock(mtd, from, &ops);
  
  	/* Exit OTP access mode */
  	this->command(mtd, ONENAND_CMD_RESET, 0, 0);
  	this->wait(mtd, FL_RESETING);
  
  	return ret;
  }
  
  /**
   * do_otp_write - [DEFAULT] Write OTP block area
   * @param mtd		MTD device structure
   * @param to		The offset to write
   * @param len		number of bytes to write
   * @param retlen	pointer to variable to store the number of write bytes
   * @param buf		the databuffer to put/get data
   *
   * Write OTP block area.
   */
  static int do_otp_write(struct mtd_info *mtd, loff_t to, size_t len,
  		size_t *retlen, u_char *buf)
  {
  	struct onenand_chip *this = mtd->priv;
  	unsigned char *pbuf = buf;
  	int ret;
  	struct mtd_oob_ops ops;
  
  	/* Force buffer page aligned */
  	if (len < mtd->writesize) {
  		memcpy(this->page_buf, buf, len);
  		memset(this->page_buf + len, 0xff, mtd->writesize - len);
  		pbuf = this->page_buf;
  		len = mtd->writesize;
  	}
  
  	/* Enter OTP access mode */
  	this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
  	this->wait(mtd, FL_OTPING);
  
  	ops.len = len;
  	ops.ooblen = 0;
  	ops.datbuf = pbuf;
  	ops.oobbuf = NULL;
  	ret = onenand_write_ops_nolock(mtd, to, &ops);
  	*retlen = ops.retlen;
  
  	/* Exit OTP access mode */
  	this->command(mtd, ONENAND_CMD_RESET, 0, 0);
  	this->wait(mtd, FL_RESETING);
  
  	return ret;
  }
  
  /**
   * do_otp_lock - [DEFAULT] Lock OTP block area
   * @param mtd		MTD device structure
   * @param from		The offset to lock
   * @param len		number of bytes to lock
   * @param retlen	pointer to variable to store the number of lock bytes
   * @param buf		the databuffer to put/get data
   *
   * Lock OTP block area.
   */
  static int do_otp_lock(struct mtd_info *mtd, loff_t from, size_t len,
  		size_t *retlen, u_char *buf)
  {
  	struct onenand_chip *this = mtd->priv;
  	struct mtd_oob_ops ops;
  	int ret;
  
  	if (FLEXONENAND(this)) {
  
  		/* Enter OTP access mode */
  		this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
  		this->wait(mtd, FL_OTPING);
  		/*
  		 * For Flex-OneNAND, we write lock mark to 1st word of sector 4 of
  		 * main area of page 49.
  		 */
  		ops.len = mtd->writesize;
  		ops.ooblen = 0;
  		ops.datbuf = buf;
  		ops.oobbuf = NULL;
  		ret = onenand_write_ops_nolock(mtd, mtd->writesize * 49, &ops);
  		*retlen = ops.retlen;
  
  		/* Exit OTP access mode */
  		this->command(mtd, ONENAND_CMD_RESET, 0, 0);
  		this->wait(mtd, FL_RESETING);
  	} else {
  		ops.mode = MTD_OPS_PLACE_OOB;
  		ops.ooblen = len;
  		ops.oobbuf = buf;
  		ops.ooboffs = 0;
  		ret = onenand_otp_write_oob_nolock(mtd, from, &ops);
  		*retlen = ops.oobretlen;
  	}
  
  	return ret;
  }
  
  /**
   * onenand_otp_walk - [DEFAULT] Handle OTP operation
   * @param mtd		MTD device structure
   * @param from		The offset to read/write
   * @param len		number of bytes to read/write
   * @param retlen	pointer to variable to store the number of read bytes
   * @param buf		the databuffer to put/get data
   * @param action	do given action
   * @param mode		specify user and factory
   *
   * Handle OTP operation.
   */
  static int onenand_otp_walk(struct mtd_info *mtd, loff_t from, size_t len,
  			size_t *retlen, u_char *buf,
  			otp_op_t action, int mode)
  {
  	struct onenand_chip *this = mtd->priv;
  	int otp_pages;
  	int density;
  	int ret = 0;
  
  	*retlen = 0;
  
  	density = onenand_get_density(this->device_id);
  	if (density < ONENAND_DEVICE_DENSITY_512Mb)
  		otp_pages = 20;
  	else
  		otp_pages = 50;
  
  	if (mode == MTD_OTP_FACTORY) {
  		from += mtd->writesize * otp_pages;
  		otp_pages = ONENAND_PAGES_PER_BLOCK - otp_pages;
  	}
  
  	/* Check User/Factory boundary */
  	if (mode == MTD_OTP_USER) {
  		if (mtd->writesize * otp_pages < from + len)
  			return 0;
  	} else {
  		if (mtd->writesize * otp_pages <  len)
  			return 0;
  	}
  
  	onenand_get_device(mtd, FL_OTPING);
  	while (len > 0 && otp_pages > 0) {
  		if (!action) {	/* OTP Info functions */
  			struct otp_info *otpinfo;
  
  			len -= sizeof(struct otp_info);
  			if (len <= 0) {
  				ret = -ENOSPC;
  				break;
  			}
  
  			otpinfo = (struct otp_info *) buf;
  			otpinfo->start = from;
  			otpinfo->length = mtd->writesize;
  			otpinfo->locked = 0;
  
  			from += mtd->writesize;
  			buf += sizeof(struct otp_info);
  			*retlen += sizeof(struct otp_info);
  		} else {
  			size_t tmp_retlen;
  
  			ret = action(mtd, from, len, &tmp_retlen, buf);
  
  			buf += tmp_retlen;
  			len -= tmp_retlen;
  			*retlen += tmp_retlen;
  
  			if (ret)
  				break;
  		}
  		otp_pages--;
  	}
  	onenand_release_device(mtd);
  
  	return ret;
  }
  
  /**
   * onenand_get_fact_prot_info - [MTD Interface] Read factory OTP info
   * @param mtd		MTD device structure
   * @param buf		the databuffer to put/get data
   * @param len		number of bytes to read
   *
   * Read factory OTP info.
   */
  static int onenand_get_fact_prot_info(struct mtd_info *mtd,
  			struct otp_info *buf, size_t len)
  {
  	size_t retlen;
  	int ret;
  
  	ret = onenand_otp_walk(mtd, 0, len, &retlen, (u_char *) buf, NULL, MTD_OTP_FACTORY);
  
  	return ret ? : retlen;
  }
  
  /**
   * onenand_read_fact_prot_reg - [MTD Interface] Read factory OTP area
   * @param mtd		MTD device structure
   * @param from		The offset to read
   * @param len		number of bytes to read
   * @param retlen	pointer to variable to store the number of read bytes
   * @param buf		the databuffer to put/get data
   *
   * Read factory OTP area.
   */
  static int onenand_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
  			size_t len, size_t *retlen, u_char *buf)
  {
  	return onenand_otp_walk(mtd, from, len, retlen, buf, do_otp_read, MTD_OTP_FACTORY);
  }
  
  /**
   * onenand_get_user_prot_info - [MTD Interface] Read user OTP info
   * @param mtd		MTD device structure
   * @param buf		the databuffer to put/get data
   * @param len		number of bytes to read
   *
   * Read user OTP info.
   */
  static int onenand_get_user_prot_info(struct mtd_info *mtd,
  			struct otp_info *buf, size_t len)
  {
  	size_t retlen;
  	int ret;
  
  	ret = onenand_otp_walk(mtd, 0, len, &retlen, (u_char *) buf, NULL, MTD_OTP_USER);
  
  	return ret ? : retlen;
  }
  
  /**
   * onenand_read_user_prot_reg - [MTD Interface] Read user OTP area
   * @param mtd		MTD device structure
   * @param from		The offset to read
   * @param len		number of bytes to read
   * @param retlen	pointer to variable to store the number of read bytes
   * @param buf		the databuffer to put/get data
   *
   * Read user OTP area.
   */
  static int onenand_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
  			size_t len, size_t *retlen, u_char *buf)
  {
  	return onenand_otp_walk(mtd, from, len, retlen, buf, do_otp_read, MTD_OTP_USER);
  }
  
  /**
   * onenand_write_user_prot_reg - [MTD Interface] Write user OTP area
   * @param mtd		MTD device structure
   * @param from		The offset to write
   * @param len		number of bytes to write
   * @param retlen	pointer to variable to store the number of write bytes
   * @param buf		the databuffer to put/get data
   *
   * Write user OTP area.
   */
  static int onenand_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
  			size_t len, size_t *retlen, u_char *buf)
  {
  	return onenand_otp_walk(mtd, from, len, retlen, buf, do_otp_write, MTD_OTP_USER);
  }
  
  /**
   * onenand_lock_user_prot_reg - [MTD Interface] Lock user OTP area
   * @param mtd		MTD device structure
   * @param from		The offset to lock
   * @param len		number of bytes to unlock
   *
   * Write lock mark on spare area in page 0 in OTP block
   */
  static int onenand_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
  			size_t len)
  {
  	struct onenand_chip *this = mtd->priv;
  	u_char *buf = FLEXONENAND(this) ? this->page_buf : this->oob_buf;
  	size_t retlen;
  	int ret;
  	unsigned int otp_lock_offset = ONENAND_OTP_LOCK_OFFSET;
  
  	memset(buf, 0xff, FLEXONENAND(this) ? this->writesize
  						 : mtd->oobsize);
  	/*
  	 * Write lock mark to 8th word of sector0 of page0 of the spare0.
  	 * We write 16 bytes spare area instead of 2 bytes.
  	 * For Flex-OneNAND, we write lock mark to 1st word of sector 4 of
  	 * main area of page 49.
  	 */
  
  	from = 0;
  	len = FLEXONENAND(this) ? mtd->writesize : 16;
  
  	/*
  	 * Note: OTP lock operation
  	 *       OTP block : 0xXXFC			XX 1111 1100
  	 *       1st block : 0xXXF3 (If chip support)	XX 1111 0011
  	 *       Both      : 0xXXF0 (If chip support)	XX 1111 0000
  	 */
  	if (FLEXONENAND(this))
  		otp_lock_offset = FLEXONENAND_OTP_LOCK_OFFSET;
  
  	/* ONENAND_OTP_AREA | ONENAND_OTP_BLOCK0 | ONENAND_OTP_AREA_BLOCK0 */
  	if (otp == 1)
  		buf[otp_lock_offset] = 0xFC;
  	else if (otp == 2)
  		buf[otp_lock_offset] = 0xF3;
  	else if (otp == 3)
  		buf[otp_lock_offset] = 0xF0;
  	else if (otp != 0)
  		printk(KERN_DEBUG "[OneNAND] Invalid option selected for OTP\n");
  
  	ret = onenand_otp_walk(mtd, from, len, &retlen, buf, do_otp_lock, MTD_OTP_USER);
  
  	return ret ? : retlen;
  }
  
  #endif	/* CONFIG_MTD_ONENAND_OTP */
  
  /**
   * onenand_check_features - Check and set OneNAND features
   * @param mtd		MTD data structure
   *
   * Check and set OneNAND features
   * - lock scheme
   * - two plane
   */
  static void onenand_check_features(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	unsigned int density, process, numbufs;
  
  	/* Lock scheme depends on density and process */
  	density = onenand_get_density(this->device_id);
  	process = this->version_id >> ONENAND_VERSION_PROCESS_SHIFT;
  	numbufs = this->read_word(this->base + ONENAND_REG_NUM_BUFFERS) >> 8;
  
  	/* Lock scheme */
  	switch (density) {
  	case ONENAND_DEVICE_DENSITY_4Gb:
  		if (ONENAND_IS_DDP(this))
  			this->options |= ONENAND_HAS_2PLANE;
  		else if (numbufs == 1) {
  			this->options |= ONENAND_HAS_4KB_PAGE;
  			this->options |= ONENAND_HAS_CACHE_PROGRAM;
  			/*
  			 * There are two different 4KiB pagesize chips
  			 * and no way to detect it by H/W config values.
  			 *
  			 * To detect the correct NOP for each chips,
  			 * It should check the version ID as workaround.
  			 *
  			 * Now it has as following
  			 * KFM4G16Q4M has NOP 4 with version ID 0x0131
  			 * KFM4G16Q5M has NOP 1 with versoin ID 0x013e
  			 */
  			if ((this->version_id & 0xf) == 0xe)
  				this->options |= ONENAND_HAS_NOP_1;
  		}
  
  	case ONENAND_DEVICE_DENSITY_2Gb:
  		/* 2Gb DDP does not have 2 plane */
  		if (!ONENAND_IS_DDP(this))
  			this->options |= ONENAND_HAS_2PLANE;
  		this->options |= ONENAND_HAS_UNLOCK_ALL;
  
  	case ONENAND_DEVICE_DENSITY_1Gb:
  		/* A-Die has all block unlock */
  		if (process)
  			this->options |= ONENAND_HAS_UNLOCK_ALL;
  		break;
  
  	default:
  		/* Some OneNAND has continuous lock scheme */
  		if (!process)
  			this->options |= ONENAND_HAS_CONT_LOCK;
  		break;
  	}
  
  	/* The MLC has 4KiB pagesize. */
  	if (ONENAND_IS_MLC(this))
  		this->options |= ONENAND_HAS_4KB_PAGE;
  
  	if (ONENAND_IS_4KB_PAGE(this))
  		this->options &= ~ONENAND_HAS_2PLANE;
  
  	if (FLEXONENAND(this)) {
  		this->options &= ~ONENAND_HAS_CONT_LOCK;
  		this->options |= ONENAND_HAS_UNLOCK_ALL;
  	}
  
  	if (this->options & ONENAND_HAS_CONT_LOCK)
  		printk(KERN_DEBUG "Lock scheme is Continuous Lock\n");
  	if (this->options & ONENAND_HAS_UNLOCK_ALL)
  		printk(KERN_DEBUG "Chip support all block unlock\n");
  	if (this->options & ONENAND_HAS_2PLANE)
  		printk(KERN_DEBUG "Chip has 2 plane\n");
  	if (this->options & ONENAND_HAS_4KB_PAGE)
  		printk(KERN_DEBUG "Chip has 4KiB pagesize\n");
  	if (this->options & ONENAND_HAS_CACHE_PROGRAM)
  		printk(KERN_DEBUG "Chip has cache program feature\n");
  }
  
  /**
   * onenand_print_device_info - Print device & version ID
   * @param device        device ID
   * @param version	version ID
   *
   * Print device & version ID
   */
  static void onenand_print_device_info(int device, int version)
  {
  	int vcc, demuxed, ddp, density, flexonenand;
  
          vcc = device & ONENAND_DEVICE_VCC_MASK;
          demuxed = device & ONENAND_DEVICE_IS_DEMUX;
          ddp = device & ONENAND_DEVICE_IS_DDP;
          density = onenand_get_density(device);
  	flexonenand = device & DEVICE_IS_FLEXONENAND;
  	printk(KERN_INFO "%s%sOneNAND%s %dMB %sV 16-bit (0x%02x)\n",
  		demuxed ? "" : "Muxed ",
  		flexonenand ? "Flex-" : "",
                  ddp ? "(DDP)" : "",
                  (16 << density),
                  vcc ? "2.65/3.3" : "1.8",
                  device);
  	printk(KERN_INFO "OneNAND version = 0x%04x\n", version);
  }
  
  static const struct onenand_manufacturers onenand_manuf_ids[] = {
          {ONENAND_MFR_SAMSUNG, "Samsung"},
  	{ONENAND_MFR_NUMONYX, "Numonyx"},
  };
  
  /**
   * onenand_check_maf - Check manufacturer ID
   * @param manuf         manufacturer ID
   *
   * Check manufacturer ID
   */
  static int onenand_check_maf(int manuf)
  {
  	int size = ARRAY_SIZE(onenand_manuf_ids);
  	char *name;
          int i;
  
  	for (i = 0; i < size; i++)
                  if (manuf == onenand_manuf_ids[i].id)
                          break;
  
  	if (i < size)
  		name = onenand_manuf_ids[i].name;
  	else
  		name = "Unknown";
  
  	printk(KERN_DEBUG "OneNAND Manufacturer: %s (0x%0x)\n", name, manuf);
  
  	return (i == size);
  }
  
  /**
  * flexonenand_get_boundary	- Reads the SLC boundary
  * @param onenand_info		- onenand info structure
  **/
  static int flexonenand_get_boundary(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	unsigned die, bdry;
  	int ret, syscfg, locked;
  
  	/* Disable ECC */
  	syscfg = this->read_word(this->base + ONENAND_REG_SYS_CFG1);
  	this->write_word((syscfg | 0x0100), this->base + ONENAND_REG_SYS_CFG1);
  
  	for (die = 0; die < this->dies; die++) {
  		this->command(mtd, FLEXONENAND_CMD_PI_ACCESS, die, 0);
  		this->wait(mtd, FL_SYNCING);
  
  		this->command(mtd, FLEXONENAND_CMD_READ_PI, die, 0);
  		ret = this->wait(mtd, FL_READING);
  
  		bdry = this->read_word(this->base + ONENAND_DATARAM);
  		if ((bdry >> FLEXONENAND_PI_UNLOCK_SHIFT) == 3)
  			locked = 0;
  		else
  			locked = 1;
  		this->boundary[die] = bdry & FLEXONENAND_PI_MASK;
  
  		this->command(mtd, ONENAND_CMD_RESET, 0, 0);
  		ret = this->wait(mtd, FL_RESETING);
  
  		printk(KERN_INFO "Die %d boundary: %d%s\n", die,
  		       this->boundary[die], locked ? "(Locked)" : "(Unlocked)");
  	}
  
  	/* Enable ECC */
  	this->write_word(syscfg, this->base + ONENAND_REG_SYS_CFG1);
  	return 0;
  }
  
  /**
   * flexonenand_get_size - Fill up fields in onenand_chip and mtd_info
   * 			  boundary[], diesize[], mtd->size, mtd->erasesize
   * @param mtd		- MTD device structure
   */
  static void flexonenand_get_size(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	int die, i, eraseshift, density;
  	int blksperdie, maxbdry;
  	loff_t ofs;
  
  	density = onenand_get_density(this->device_id);
  	blksperdie = ((loff_t)(16 << density) << 20) >> (this->erase_shift);
  	blksperdie >>= ONENAND_IS_DDP(this) ? 1 : 0;
  	maxbdry = blksperdie - 1;
  	eraseshift = this->erase_shift - 1;
  
  	mtd->numeraseregions = this->dies << 1;
  
  	/* This fills up the device boundary */
  	flexonenand_get_boundary(mtd);
  	die = ofs = 0;
  	i = -1;
  	for (; die < this->dies; die++) {
  		if (!die || this->boundary[die-1] != maxbdry) {
  			i++;
  			mtd->eraseregions[i].offset = ofs;
  			mtd->eraseregions[i].erasesize = 1 << eraseshift;
  			mtd->eraseregions[i].numblocks =
  							this->boundary[die] + 1;
  			ofs += mtd->eraseregions[i].numblocks << eraseshift;
  			eraseshift++;
  		} else {
  			mtd->numeraseregions -= 1;
  			mtd->eraseregions[i].numblocks +=
  							this->boundary[die] + 1;
  			ofs += (this->boundary[die] + 1) << (eraseshift - 1);
  		}
  		if (this->boundary[die] != maxbdry) {
  			i++;
  			mtd->eraseregions[i].offset = ofs;
  			mtd->eraseregions[i].erasesize = 1 << eraseshift;
  			mtd->eraseregions[i].numblocks = maxbdry ^
  							 this->boundary[die];
  			ofs += mtd->eraseregions[i].numblocks << eraseshift;
  			eraseshift--;
  		} else
  			mtd->numeraseregions -= 1;
  	}
  
  	/* Expose MLC erase size except when all blocks are SLC */
  	mtd->erasesize = 1 << this->erase_shift;
  	if (mtd->numeraseregions == 1)
  		mtd->erasesize >>= 1;
  
  	printk(KERN_INFO "Device has %d eraseregions\n", mtd->numeraseregions);
  	for (i = 0; i < mtd->numeraseregions; i++)
  		printk(KERN_INFO "[offset: 0x%08x, erasesize: 0x%05x,"
  			" numblocks: %04u]\n",
  			(unsigned int) mtd->eraseregions[i].offset,
  			mtd->eraseregions[i].erasesize,
  			mtd->eraseregions[i].numblocks);
  
  	for (die = 0, mtd->size = 0; die < this->dies; die++) {
  		this->diesize[die] = (loff_t)blksperdie << this->erase_shift;
  		this->diesize[die] -= (loff_t)(this->boundary[die] + 1)
  						 << (this->erase_shift - 1);
  		mtd->size += this->diesize[die];
  	}
  }
  
  /**
   * flexonenand_check_blocks_erased - Check if blocks are erased
   * @param mtd_info	- mtd info structure
   * @param start		- first erase block to check
   * @param end		- last erase block to check
   *
   * Converting an unerased block from MLC to SLC
   * causes byte values to change. Since both data and its ECC
   * have changed, reads on the block give uncorrectable error.
   * This might lead to the block being detected as bad.
   *
   * Avoid this by ensuring that the block to be converted is
   * erased.
   */
  static int flexonenand_check_blocks_erased(struct mtd_info *mtd, int start, int end)
  {
  	struct onenand_chip *this = mtd->priv;
  	int i, ret;
  	int block;
  	struct mtd_oob_ops ops = {
  		.mode = MTD_OPS_PLACE_OOB,
  		.ooboffs = 0,
  		.ooblen	= mtd->oobsize,
  		.datbuf	= NULL,
  		.oobbuf	= this->oob_buf,
  	};
  	loff_t addr;
  
  	printk(KERN_DEBUG "Check blocks from %d to %d\n", start, end);
  
  	for (block = start; block <= end; block++) {
  		addr = flexonenand_addr(this, block);
  		if (onenand_block_isbad_nolock(mtd, addr, 0))
  			continue;
  
  		/*
  		 * Since main area write results in ECC write to spare,
  		 * it is sufficient to check only ECC bytes for change.
  		 */
  		ret = onenand_read_oob_nolock(mtd, addr, &ops);
  		if (ret)
  			return ret;
  
  		for (i = 0; i < mtd->oobsize; i++)
  			if (this->oob_buf[i] != 0xff)
  				break;
  
  		if (i != mtd->oobsize) {
  			printk(KERN_WARNING "%s: Block %d not erased.\n",
  				__func__, block);
  			return 1;
  		}
  	}
  
  	return 0;
  }
  
  /**
   * flexonenand_set_boundary	- Writes the SLC boundary
   * @param mtd			- mtd info structure
   */
  static int flexonenand_set_boundary(struct mtd_info *mtd, int die,
  				    int boundary, int lock)
  {
  	struct onenand_chip *this = mtd->priv;
  	int ret, density, blksperdie, old, new, thisboundary;
  	loff_t addr;
  
  	/* Change only once for SDP Flex-OneNAND */
  	if (die && (!ONENAND_IS_DDP(this)))
  		return 0;
  
  	/* boundary value of -1 indicates no required change */
  	if (boundary < 0 || boundary == this->boundary[die])
  		return 0;
  
  	density = onenand_get_density(this->device_id);
  	blksperdie = ((16 << density) << 20) >> this->erase_shift;
  	blksperdie >>= ONENAND_IS_DDP(this) ? 1 : 0;
  
  	if (boundary >= blksperdie) {
  		printk(KERN_ERR "%s: Invalid boundary value. "
  				"Boundary not changed.\n", __func__);
  		return -EINVAL;
  	}
  
  	/* Check if converting blocks are erased */
  	old = this->boundary[die] + (die * this->density_mask);
  	new = boundary + (die * this->density_mask);
  	ret = flexonenand_check_blocks_erased(mtd, min(old, new) + 1, max(old, new));
  	if (ret) {
  		printk(KERN_ERR "%s: Please erase blocks "
  				"before boundary change\n", __func__);
  		return ret;
  	}
  
  	this->command(mtd, FLEXONENAND_CMD_PI_ACCESS, die, 0);
  	this->wait(mtd, FL_SYNCING);
  
  	/* Check is boundary is locked */
  	this->command(mtd, FLEXONENAND_CMD_READ_PI, die, 0);
  	ret = this->wait(mtd, FL_READING);
  
  	thisboundary = this->read_word(this->base + ONENAND_DATARAM);
  	if ((thisboundary >> FLEXONENAND_PI_UNLOCK_SHIFT) != 3) {
  		printk(KERN_ERR "%s: boundary locked\n", __func__);
  		ret = 1;
  		goto out;
  	}
  
  	printk(KERN_INFO "Changing die %d boundary: %d%s\n",
  			die, boundary, lock ? "(Locked)" : "(Unlocked)");
  
  	addr = die ? this->diesize[0] : 0;
  
  	boundary &= FLEXONENAND_PI_MASK;
  	boundary |= lock ? 0 : (3 << FLEXONENAND_PI_UNLOCK_SHIFT);
  
  	this->command(mtd, ONENAND_CMD_ERASE, addr, 0);
  	ret = this->wait(mtd, FL_ERASING);
  	if (ret) {
  		printk(KERN_ERR "%s: Failed PI erase for Die %d\n",
  		       __func__, die);
  		goto out;
  	}
  
  	this->write_word(boundary, this->base + ONENAND_DATARAM);
  	this->command(mtd, ONENAND_CMD_PROG, addr, 0);
  	ret = this->wait(mtd, FL_WRITING);
  	if (ret) {
  		printk(KERN_ERR "%s: Failed PI write for Die %d\n",
  			__func__, die);
  		goto out;
  	}
  
  	this->command(mtd, FLEXONENAND_CMD_PI_UPDATE, die, 0);
  	ret = this->wait(mtd, FL_WRITING);
  out:
  	this->write_word(ONENAND_CMD_RESET, this->base + ONENAND_REG_COMMAND);
  	this->wait(mtd, FL_RESETING);
  	if (!ret)
  		/* Recalculate device size on boundary change*/
  		flexonenand_get_size(mtd);
  
  	return ret;
  }
  
  /**
   * onenand_chip_probe - [OneNAND Interface] The generic chip probe
   * @param mtd		MTD device structure
   *
   * OneNAND detection method:
   *   Compare the values from command with ones from register
   */
  static int onenand_chip_probe(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	int bram_maf_id, bram_dev_id, maf_id, dev_id;
  	int syscfg;
  
  	/* Save system configuration 1 */
  	syscfg = this->read_word(this->base + ONENAND_REG_SYS_CFG1);
  	/* Clear Sync. Burst Read mode to read BootRAM */
  	this->write_word((syscfg & ~ONENAND_SYS_CFG1_SYNC_READ & ~ONENAND_SYS_CFG1_SYNC_WRITE), this->base + ONENAND_REG_SYS_CFG1);
  
  	/* Send the command for reading device ID from BootRAM */
  	this->write_word(ONENAND_CMD_READID, this->base + ONENAND_BOOTRAM);
  
  	/* Read manufacturer and device IDs from BootRAM */
  	bram_maf_id = this->read_word(this->base + ONENAND_BOOTRAM + 0x0);
  	bram_dev_id = this->read_word(this->base + ONENAND_BOOTRAM + 0x2);
  
  	/* Reset OneNAND to read default register values */
  	this->write_word(ONENAND_CMD_RESET, this->base + ONENAND_BOOTRAM);
  	/* Wait reset */
  	this->wait(mtd, FL_RESETING);
  
  	/* Restore system configuration 1 */
  	this->write_word(syscfg, this->base + ONENAND_REG_SYS_CFG1);
  
  	/* Check manufacturer ID */
  	if (onenand_check_maf(bram_maf_id))
  		return -ENXIO;
  
  	/* Read manufacturer and device IDs from Register */
  	maf_id = this->read_word(this->base + ONENAND_REG_MANUFACTURER_ID);
  	dev_id = this->read_word(this->base + ONENAND_REG_DEVICE_ID);
  
  	/* Check OneNAND device */
  	if (maf_id != bram_maf_id || dev_id != bram_dev_id)
  		return -ENXIO;
  
  	return 0;
  }
  
  /**
   * onenand_probe - [OneNAND Interface] Probe the OneNAND device
   * @param mtd		MTD device structure
   */
  static int onenand_probe(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  	int maf_id, dev_id, ver_id;
  	int density;
  	int ret;
  
  	ret = this->chip_probe(mtd);
  	if (ret)
  		return ret;
  
  	/* Read manufacturer and device IDs from Register */
  	maf_id = this->read_word(this->base + ONENAND_REG_MANUFACTURER_ID);
  	dev_id = this->read_word(this->base + ONENAND_REG_DEVICE_ID);
  	ver_id = this->read_word(this->base + ONENAND_REG_VERSION_ID);
  	this->technology = this->read_word(this->base + ONENAND_REG_TECHNOLOGY);
  
  	/* Flash device information */
  	onenand_print_device_info(dev_id, ver_id);
  	this->device_id = dev_id;
  	this->version_id = ver_id;
  
  	/* Check OneNAND features */
  	onenand_check_features(mtd);
  
  	density = onenand_get_density(dev_id);
  	if (FLEXONENAND(this)) {
  		this->dies = ONENAND_IS_DDP(this) ? 2 : 1;
  		/* Maximum possible erase regions */
  		mtd->numeraseregions = this->dies << 1;
  		mtd->eraseregions = kzalloc(sizeof(struct mtd_erase_region_info)
  					* (this->dies << 1), GFP_KERNEL);
  		if (!mtd->eraseregions)
  			return -ENOMEM;
  	}
  
  	/*
  	 * For Flex-OneNAND, chipsize represents maximum possible device size.
  	 * mtd->size represents the actual device size.
  	 */
  	this->chipsize = (16 << density) << 20;
  
  	/* OneNAND page size & block size */
  	/* The data buffer size is equal to page size */
  	mtd->writesize = this->read_word(this->base + ONENAND_REG_DATA_BUFFER_SIZE);
  	/* We use the full BufferRAM */
  	if (ONENAND_IS_4KB_PAGE(this))
  		mtd->writesize <<= 1;
  
  	mtd->oobsize = mtd->writesize >> 5;
  	/* Pages per a block are always 64 in OneNAND */
  	mtd->erasesize = mtd->writesize << 6;
  	/*
  	 * Flex-OneNAND SLC area has 64 pages per block.
  	 * Flex-OneNAND MLC area has 128 pages per block.
  	 * Expose MLC erase size to find erase_shift and page_mask.
  	 */
  	if (FLEXONENAND(this))
  		mtd->erasesize <<= 1;
  
  	this->erase_shift = ffs(mtd->erasesize) - 1;
  	this->page_shift = ffs(mtd->writesize) - 1;
  	this->page_mask = (1 << (this->erase_shift - this->page_shift)) - 1;
  	/* Set density mask. it is used for DDP */
  	if (ONENAND_IS_DDP(this))
  		this->density_mask = this->chipsize >> (this->erase_shift + 1);
  	/* It's real page size */
  	this->writesize = mtd->writesize;
  
  	/* REVISIT: Multichip handling */
  
  	if (FLEXONENAND(this))
  		flexonenand_get_size(mtd);
  	else
  		mtd->size = this->chipsize;
  
  	/*
  	 * We emulate the 4KiB page and 256KiB erase block size
  	 * But oobsize is still 64 bytes.
  	 * It is only valid if you turn on 2X program support,
  	 * Otherwise it will be ignored by compiler.
  	 */
  	if (ONENAND_IS_2PLANE(this)) {
  		mtd->writesize <<= 1;
  		mtd->erasesize <<= 1;
  	}
  
  	return 0;
  }
  
  /**
   * onenand_suspend - [MTD Interface] Suspend the OneNAND flash
   * @param mtd		MTD device structure
   */
  static int onenand_suspend(struct mtd_info *mtd)
  {
  	return onenand_get_device(mtd, FL_PM_SUSPENDED);
  }
  
  /**
   * onenand_resume - [MTD Interface] Resume the OneNAND flash
   * @param mtd		MTD device structure
   */
  static void onenand_resume(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  
  	if (this->state == FL_PM_SUSPENDED)
  		onenand_release_device(mtd);
  	else
  		printk(KERN_ERR "%s: resume() called for the chip which is not "
  				"in suspended state\n", __func__);
  }
  
  /**
   * onenand_scan - [OneNAND Interface] Scan for the OneNAND device
   * @param mtd		MTD device structure
   * @param 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.
   */
  int onenand_scan(struct mtd_info *mtd, int maxchips)
  {
  	int i, ret;
  	struct onenand_chip *this = mtd->priv;
  
  	if (!this->read_word)
  		this->read_word = onenand_readw;
  	if (!this->write_word)
  		this->write_word = onenand_writew;
  
  	if (!this->command)
  		this->command = onenand_command;
  	if (!this->wait)
  		onenand_setup_wait(mtd);
  	if (!this->bbt_wait)
  		this->bbt_wait = onenand_bbt_wait;
  	if (!this->unlock_all)
  		this->unlock_all = onenand_unlock_all;
  
  	if (!this->chip_probe)
  		this->chip_probe = onenand_chip_probe;
  
  	if (!this->read_bufferram)
  		this->read_bufferram = onenand_read_bufferram;
  	if (!this->write_bufferram)
  		this->write_bufferram = onenand_write_bufferram;
  
  	if (!this->block_markbad)
  		this->block_markbad = onenand_default_block_markbad;
  	if (!this->scan_bbt)
  		this->scan_bbt = onenand_default_bbt;
  
  	if (onenand_probe(mtd))
  		return -ENXIO;
  
  	/* Set Sync. Burst Read after probing */
  	if (this->mmcontrol) {
  		printk(KERN_INFO "OneNAND Sync. Burst Read support\n");
  		this->read_bufferram = onenand_sync_read_bufferram;
  	}
  
  	/* Allocate buffers, if necessary */
  	if (!this->page_buf) {
  		this->page_buf = kzalloc(mtd->writesize, GFP_KERNEL);
  		if (!this->page_buf) {
  			printk(KERN_ERR "%s: Can't allocate page_buf\n",
  				__func__);
  			return -ENOMEM;
  		}
  #ifdef CONFIG_MTD_ONENAND_VERIFY_WRITE
  		this->verify_buf = kzalloc(mtd->writesize, GFP_KERNEL);
  		if (!this->verify_buf) {
  			kfree(this->page_buf);
  			return -ENOMEM;
  		}
  #endif
  		this->options |= ONENAND_PAGEBUF_ALLOC;
  	}
  	if (!this->oob_buf) {
  		this->oob_buf = kzalloc(mtd->oobsize, GFP_KERNEL);
  		if (!this->oob_buf) {
  			printk(KERN_ERR "%s: Can't allocate oob_buf\n",
  				__func__);
  			if (this->options & ONENAND_PAGEBUF_ALLOC) {
  				this->options &= ~ONENAND_PAGEBUF_ALLOC;
  				kfree(this->page_buf);
  			}
  			return -ENOMEM;
  		}
  		this->options |= ONENAND_OOBBUF_ALLOC;
  	}
  
  	this->state = FL_READY;
  	init_waitqueue_head(&this->wq);
  	spin_lock_init(&this->chip_lock);
  
  	/*
  	 * Allow subpage writes up to oobsize.
  	 */
  	switch (mtd->oobsize) {
  	case 128:
  		if (FLEXONENAND(this)) {
  			this->ecclayout = &flexonenand_oob_128;
  			mtd->subpage_sft = 0;
  		} else {
  			this->ecclayout = &onenand_oob_128;
  			mtd->subpage_sft = 2;
  		}
  		if (ONENAND_IS_NOP_1(this))
  			mtd->subpage_sft = 0;
  		break;
  	case 64:
  		this->ecclayout = &onenand_oob_64;
  		mtd->subpage_sft = 2;
  		break;
  
  	case 32:
  		this->ecclayout = &onenand_oob_32;
  		mtd->subpage_sft = 1;
  		break;
  
  	default:
  		printk(KERN_WARNING "%s: No OOB scheme defined for oobsize %d\n",
  			__func__, mtd->oobsize);
  		mtd->subpage_sft = 0;
  		/* To prevent kernel oops */
  		this->ecclayout = &onenand_oob_32;
  		break;
  	}
  
  	this->subpagesize = mtd->writesize >> mtd->subpage_sft;
  
  	/*
  	 * The number of bytes available for a client to place data into
  	 * the out of band area
  	 */
  	this->ecclayout->oobavail = 0;
  	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES &&
  	    this->ecclayout->oobfree[i].length; i++)
  		this->ecclayout->oobavail +=
  			this->ecclayout->oobfree[i].length;
  	mtd->oobavail = this->ecclayout->oobavail;
  
  	mtd->ecclayout = this->ecclayout;
  	mtd->ecc_strength = 1;
  
  	/* Fill in remaining MTD driver data */
  	mtd->type = ONENAND_IS_MLC(this) ? MTD_MLCNANDFLASH : MTD_NANDFLASH;
  	mtd->flags = MTD_CAP_NANDFLASH;
  	mtd->_erase = onenand_erase;
  	mtd->_point = NULL;
  	mtd->_unpoint = NULL;
  	mtd->_read = onenand_read;
  	mtd->_write = onenand_write;
  	mtd->_read_oob = onenand_read_oob;
  	mtd->_write_oob = onenand_write_oob;
  	mtd->_panic_write = onenand_panic_write;
  #ifdef CONFIG_MTD_ONENAND_OTP
  	mtd->_get_fact_prot_info = onenand_get_fact_prot_info;
  	mtd->_read_fact_prot_reg = onenand_read_fact_prot_reg;
  	mtd->_get_user_prot_info = onenand_get_user_prot_info;
  	mtd->_read_user_prot_reg = onenand_read_user_prot_reg;
  	mtd->_write_user_prot_reg = onenand_write_user_prot_reg;
  	mtd->_lock_user_prot_reg = onenand_lock_user_prot_reg;
  #endif
  	mtd->_sync = onenand_sync;
  	mtd->_lock = onenand_lock;
  	mtd->_unlock = onenand_unlock;
  	mtd->_suspend = onenand_suspend;
  	mtd->_resume = onenand_resume;
  	mtd->_block_isbad = onenand_block_isbad;
  	mtd->_block_markbad = onenand_block_markbad;
  	mtd->owner = THIS_MODULE;
  	mtd->writebufsize = mtd->writesize;
  
  	/* Unlock whole block */
  	if (!(this->options & ONENAND_SKIP_INITIAL_UNLOCKING))
  		this->unlock_all(mtd);
  
  	ret = this->scan_bbt(mtd);
  	if ((!FLEXONENAND(this)) || ret)
  		return ret;
  
  	/* Change Flex-OneNAND boundaries if required */
  	for (i = 0; i < MAX_DIES; i++)
  		flexonenand_set_boundary(mtd, i, flex_bdry[2 * i],
  						 flex_bdry[(2 * i) + 1]);
  
  	return 0;
  }
  
  /**
   * onenand_release - [OneNAND Interface] Free resources held by the OneNAND device
   * @param mtd		MTD device structure
   */
  void onenand_release(struct mtd_info *mtd)
  {
  	struct onenand_chip *this = mtd->priv;
  
  	/* Deregister partitions */
  	mtd_device_unregister(mtd);
  
  	/* Free bad block table memory, if allocated */
  	if (this->bbm) {
  		struct bbm_info *bbm = this->bbm;
  		kfree(bbm->bbt);
  		kfree(this->bbm);
  	}
  	/* Buffers allocated by onenand_scan */
  	if (this->options & ONENAND_PAGEBUF_ALLOC) {
  		kfree(this->page_buf);
  #ifdef CONFIG_MTD_ONENAND_VERIFY_WRITE
  		kfree(this->verify_buf);
  #endif
  	}
  	if (this->options & ONENAND_OOBBUF_ALLOC)
  		kfree(this->oob_buf);
  	kfree(mtd->eraseregions);
  }
  
  EXPORT_SYMBOL_GPL(onenand_scan);
  EXPORT_SYMBOL_GPL(onenand_release);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Kyungmin Park <kyungmin.park@samsung.com>");
  MODULE_DESCRIPTION("Generic OneNAND flash driver code");
  