From abc37e6771ec92bb4c531d218ad572afbef6aa21 Mon Sep 17 00:00:00 2001 From: Dan Brown Date: Thu, 7 Apr 2005 15:22:58 +0100 Subject: [MTD] DiskOnChip: Add some comments Add helpful comment about oobfree so I can't claim two years from now that I don't remember what I was thinking. Signed-off-by: Dan Brown Signed-off-by: Thomas Gleixner --- drivers/mtd/nand/diskonchip.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'drivers/mtd/nand') diff --git a/drivers/mtd/nand/diskonchip.c b/drivers/mtd/nand/diskonchip.c index 9f33f335a39..fdb5d4ad3d5 100644 --- a/drivers/mtd/nand/diskonchip.c +++ b/drivers/mtd/nand/diskonchip.c @@ -16,7 +16,7 @@ * * Interface to generic NAND code for M-Systems DiskOnChip devices * - * $Id: diskonchip.c,v 1.53 2005/04/07 13:39:13 dbrown Exp $ + * $Id: diskonchip.c,v 1.54 2005/04/07 14:22:55 dbrown Exp $ */ #include @@ -1049,6 +1049,16 @@ static int doc200x_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ //u_char mydatabuf[528]; +/* The strange out-of-order .oobfree list below is a (possibly unneeded) + * attempt to retain compatibility. It used to read: + * .oobfree = { {8, 8} } + * Since that leaves two bytes unusable, it was changed. But the following + * scheme might affect existing jffs2 installs by moving the cleanmarker: + * .oobfree = { {6, 10} } + * jffs2 seems to handle the above gracefully, but the current scheme seems + * safer. The only problem with it is that any code that parses oobfree must + * be able to handle out-of-order segments. + */ static struct nand_oobinfo doc200x_oobinfo = { .useecc = MTD_NANDECC_AUTOPLACE, .eccbytes = 6, -- cgit v1.2.3