diff options
author | Arve Hjønnevåg <arve@android.com> | 2010-05-18 20:35:30 -0700 |
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committer | Dan Willemsen <dwillemsen@nvidia.com> | 2011-11-30 21:38:10 -0800 |
commit | 62a5ed5185d19e163afbf7be97b7491f880ec7bb (patch) | |
tree | a391b7d6419bcdd72525580f471677f60fad058b /fs/yaffs2/yaffs_ecc.h | |
parent | f472945b310e1d6bbb51efa38e0f4c0248eec068 (diff) |
fs: yaffs: Import yaffs from Thu Dec 23 13:31:37 2010 +1300
commit ddf33fed15c2376bfb602d62dd018c63fce60df8
Author: Timothy Manning <tfhmanning@gmail.com>
Date: Thu Dec 23 13:31:37 2010 +1300
yaffs updated direct/timothy_tests/quick_tests
Signed-off-by: Timothy Manning <tfhmanning@gmail.com>
Change-Id: I5bbe5a05277bdf8a6fe188bbe4c77725b3fa2aae
Signed-off-by: Dima Zavin <dima@android.com>
Diffstat (limited to 'fs/yaffs2/yaffs_ecc.h')
-rw-r--r-- | fs/yaffs2/yaffs_ecc.h | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/fs/yaffs2/yaffs_ecc.h b/fs/yaffs2/yaffs_ecc.h new file mode 100644 index 000000000000..b0c461d699e6 --- /dev/null +++ b/fs/yaffs2/yaffs_ecc.h @@ -0,0 +1,44 @@ +/* + * 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__ + +struct yaffs_ecc_other { + unsigned char col_parity; + unsigned line_parity; + unsigned line_parity_prime; +}; + +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, + struct yaffs_ecc_other *ecc); +int yaffs_ecc_correct_other(unsigned char *data, unsigned n_bytes, + struct yaffs_ecc_other *read_ecc, + const struct yaffs_ecc_other *test_ecc); +#endif |