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
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+++ b/fs/yaffs2/yaffs_ecc.h
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+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system. 
+ *
+ * Copyright (C) 2002-2007 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_ECCCalculate(const unsigned char *data, unsigned char *ecc);
+int yaffs_ECCCorrect(unsigned char *data, unsigned char *read_ecc,
+		     const unsigned char *test_ecc);
+
+void yaffs_ECCCalculateOther(const unsigned char *data, unsigned nBytes,
+			     yaffs_ECCOther * ecc);
+int yaffs_ECCCorrectOther(unsigned char *data, unsigned nBytes,
+			  yaffs_ECCOther * read_ecc,
+			  const yaffs_ECCOther * test_ecc);
+#endif