/*
 *  linux/include/linux/mtd/nand.h
 *
 *  Copyright (c) 2000 David Woodhouse <dwmw2@mvhi.com>
 *                     Steven J. Hill <sjhill@realitydiluted.com>
 *		       Thomas Gleixner <tglx@linutronix.de>
 *
 * $Id: nand.h,v 1.25 2003/05/21 15:15:02 dwmw2 Exp $
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  Info:
 *   Contains standard defines and IDs for NAND flash devices
 *
 *  Changelog:
 *   01-31-2000 DMW     Created
 *   09-18-2000 SJH     Moved structure out of the Disk-On-Chip drivers
 *			so it can be used by other NAND flash device
 *			drivers. I also changed the copyright since none
 *			of the original contents of this file are specific
 *			to DoC devices. David can whack me with a baseball
 *			bat later if I did something naughty.
 *   10-11-2000 SJH     Added private NAND flash structure for driver
 *   10-24-2000 SJH     Added prototype for 'nand_scan' function
 *   10-29-2001 TG	changed nand_chip structure to support 
 *			hardwarespecific function for accessing control lines
 *   02-21-2002 TG	added support for different read/write adress and
 *			ready/busy line access function
 *   02-26-2002 TG	added chip_delay to nand_chip structure to optimize
 *			command delay times for different chips
 *   04-28-2002 TG	OOB config defines moved from nand.c to avoid duplicate
 *			defines in jffs2/wbuf.c
 *   08-07-2002 TG	forced bad block location to byte 5 of OOB, even if
 *			CONFIG_MTD_NAND_ECC_JFFS2 is not set
 *   08-10-2002 TG	extensions to nand_chip structure to support HW-ECC
 *
 *   08-29-2002 tglx 	nand_chip structure: data_poi for selecting 
 *			internal / fs-driver buffer
 *			support for 6byte/512byte hardware ECC
 *			read_ecc, write_ecc extended for different oob-layout
 *			oob layout selections: NAND_NONE_OOB, NAND_JFFS2_OOB,
 *			NAND_YAFFS_OOB
 *  11-25-2002 tglx	Added Manufacturer code FUJITSU, NATIONAL
 *			Split manufacturer and device ID structures 
 */
#ifndef __LINUX_MTD_NAND_H
#define __LINUX_MTD_NAND_H

#include <linux/config.h>
#include <linux/wait.h>
#include <linux/spinlock.h>

struct mtd_info;
/*
 * Searches for a NAND device
 */
extern int nand_scan (struct mtd_info *mtd);

/*
 * Constants for hardware specific CLE/ALE/NCE function
*/
#define NAND_CTL_SETNCE 	1
#define NAND_CTL_CLRNCE		2
#define NAND_CTL_SETCLE		3
#define NAND_CTL_CLRCLE		4
#define NAND_CTL_SETALE		5
#define NAND_CTL_CLRALE		6

/*
 * Standard NAND flash commands
 */
#define NAND_CMD_READ0		0
#define NAND_CMD_READ1		1
#define NAND_CMD_PAGEPROG	0x10
#define NAND_CMD_READOOB	0x50
#define NAND_CMD_ERASE1		0x60
#define NAND_CMD_STATUS		0x70
#define NAND_CMD_SEQIN		0x80
#define NAND_CMD_READID		0x90
#define NAND_CMD_ERASE2		0xd0
#define NAND_CMD_RESET		0xff

/* 
 * Constants for ECC_MODES
 *
 * NONE:	No ECC
 * SOFT:	Software ECC 3 byte ECC per 256 Byte data
 * HW3_256:	Hardware ECC 3 byte ECC per 256 Byte data
 * HW3_512:	Hardware ECC 3 byte ECC per 512 Byte data
 *
 *
*/
#define NAND_ECC_NONE		0
#define NAND_ECC_SOFT		1
#define NAND_ECC_HW3_256	2
#define NAND_ECC_HW3_512	3
#define NAND_ECC_HW6_512	4
#define NAND_ECC_DISKONCHIP	5

/*
 * Constants for Hardware ECC
*/
#define NAND_ECC_READ		0
#define NAND_ECC_WRITE		1
	
/*
 * Enumeration for NAND flash chip state
 */
typedef enum {
	FL_READY,
	FL_READING,
	FL_WRITING,
	FL_ERASING,
	FL_SYNCING
} nand_state_t;


/*
 * NAND Private Flash Chip Data
 *
 * Structure overview:
 *
 *  IO_ADDR_R - address to read the 8 I/O lines of the flash device 
 *
 *  IO_ADDR_W - address to write the 8 I/O lines of the flash device 
 *
 *  hwcontrol - hardwarespecific function for accesing control-lines
 *
 *  dev_ready - hardwarespecific function for accesing device ready/busy line
 *
 *  waitfunc - hardwarespecific function for wait on ready
 *
 *  calculate_ecc - function for ecc calculation or readback from ecc hardware
 *
 *  correct_data - function for ecc correction, matching to ecc generator (sw/hw)
 *
 *  enable_hwecc - function to enable (reset) hardware ecc generator
 *
 *  eccmod - mode of ecc: see constants
 *
 *  eccsize - databytes used per ecc-calculation
 *
 *  chip_delay - chip dependent delay for transfering data from array to read regs (tR)
 *
 *  chip_lock - spinlock used to protect access to this structure
 *
 *  wq - wait queue to sleep on if a NAND operation is in progress
 *
 *  state - give the current state of the NAND device
 *
 *  page_shift - number of address bits in a page (column address bits)
 *
 *  data_buf - data buffer passed to/from MTD user modules
 *
 *  data_cache - data cache for redundant page access and shadow for
 *		 ECC failure
 *
 *  cache_page - number of last valid page in page_cache 
 */
struct nand_chip {
	unsigned long 	IO_ADDR_R;
	unsigned long 	IO_ADDR_W;
	void 		(*hwcontrol)(int cmd);
	int  		(*dev_ready)(void);
	void 		(*cmdfunc)(struct mtd_info *mtd, unsigned command, int column, int page_addr);
	int 		(*waitfunc)(struct mtd_info *mtd, struct nand_chip *this, int state);
	void		(*calculate_ecc)(const u_char *dat, u_char *ecc_code);
	int 		(*correct_data)(u_char *dat, u_char *read_ecc, u_char *calc_ecc);
	void		(*enable_hwecc)(int mode);
	int		eccmode;
	int		eccsize;
	int 		chip_delay;
	spinlock_t 	chip_lock;
	wait_queue_head_t wq;
	nand_state_t 	state;
	int 		page_shift;
	u_char 		*data_buf;
	u_char		*data_poi;
};

/*
 * NAND Flash Manufacturer ID Codes
 */
#define NAND_MFR_TOSHIBA	0x98
#define NAND_MFR_SAMSUNG	0xec
#define NAND_MFR_FUJITSU	0x04
#define NAND_MFR_NATIONAL	0x8f

/*
 * NAND Flash Device ID Structure
 *
 * Structure overview:
 *
 *  name - Identify the device type
 *
 *  id -  device ID code
 *
 *  chipshift - total number of address bits for the device which
 *              is used to calculate address offsets and the total
 *              number of bytes the device is capable of.
 *
 *  page256 - denotes if flash device has 256 byte pages or not.
 *
 *  pageadrlen - number of bytes minus one needed to hold the
 *               complete address into the flash array. Keep in
 *               mind that when a read or write is done to a
 *               specific address, the address is input serially
 *               8 bits at a time. This structure member is used
 *               by the read/write routines as a loop index for
 *               shifting the address out 8 bits at a time.
 *
 *  erasesize - size of an erase block in the flash device.
 */
struct nand_flash_dev {
	char * name;
	int id;
	int chipshift;
	unsigned long erasesize;
	char page256;
};

/*
 * NAND Flash Manufacturer ID Structure
 *
 *  name - Manufacturer name
 *
 *  id - manufacturer ID code of device.
*/
struct nand_manufacturers {
	int id;
	char * name;
};

extern struct nand_flash_dev nand_flash_ids[];
extern struct nand_manufacturers nand_manuf_ids[];

/*
* Constants for oob configuration
*/
#define NAND_BADBLOCK_POS		5

#endif /* __LINUX_MTD_NAND_H */