mirror of
				git://git.openwrt.org/openwrt/openwrt.git
				synced 2025-10-31 14:04:26 -04:00 
			
		
		
		
	
		
			
				
	
	
		
			45 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			45 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
 | |
|  *
 | |
|  * Copyright (C) 2002-2010 Aleph One Ltd.
 | |
|  *   for Toby Churchill Ltd and Brightstar Engineering
 | |
|  *
 | |
|  * Created by Charles Manning <charles@aleph1.co.uk>
 | |
|  *
 | |
|  * This program is free software; you can redistribute it and/or modify
 | |
|  * it under the terms of the GNU Lesser General Public License version 2.1 as
 | |
|  * published by the Free Software Foundation.
 | |
|  *
 | |
|  * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
 | |
|  */
 | |
| 
 | |
| /*
 | |
|  * This code implements the ECC algorithm used in SmartMedia.
 | |
|  *
 | |
|  * The ECC comprises 22 bits of parity information and is stuffed into 3 bytes.
 | |
|  * The two unused bit are set to 1.
 | |
|  * The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC
 | |
|  * blocks are used on a 512-byte NAND page.
 | |
|  *
 | |
|  */
 | |
| 
 | |
| #ifndef __YAFFS_ECC_H__
 | |
| #define __YAFFS_ECC_H__
 | |
| 
 | |
| typedef struct {
 | |
| 	unsigned char colParity;
 | |
| 	unsigned lineParity;
 | |
| 	unsigned lineParityPrime;
 | |
| } yaffs_ECCOther;
 | |
| 
 | |
| void yaffs_ecc_cacl(const unsigned char *data, unsigned char *ecc);
 | |
| int yaffs_ecc_correct(unsigned char *data, unsigned char *read_ecc,
 | |
| 		const unsigned char *test_ecc);
 | |
| 
 | |
| void yaffs_ecc_calc_other(const unsigned char *data, unsigned n_bytes,
 | |
| 			yaffs_ECCOther *ecc);
 | |
| int yaffs_ecc_correct_other(unsigned char *data, unsigned n_bytes,
 | |
| 			yaffs_ECCOther *read_ecc,
 | |
| 			const yaffs_ECCOther *test_ecc);
 | |
| #endif
 |