Commit 6a623e07 authored by Alexander Couzens's avatar Alexander Couzens Committed by Brian Norris

mtd: nand: add ooblayout for old hamming layout

The old 1-bit hamming layout requires ECC data to be placed at a
fixed offset, and not necessarily at the end of the OOB area.
Add this old layout back in order to fix legacy setups.

Fixes: 41b207a7 ("mtd: nand: implement the default mtd_ooblayout_ops")
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarAlexander Couzens <lynxis@fe80.eu>
Acked-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent b98e1995
......@@ -139,6 +139,74 @@ const struct mtd_ooblayout_ops nand_ooblayout_lp_ops = {
};
EXPORT_SYMBOL_GPL(nand_ooblayout_lp_ops);
/*
* Support the old "large page" layout used for 1-bit Hamming ECC where ECC
* are placed at a fixed offset.
*/
static int nand_ooblayout_ecc_lp_hamming(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
if (section)
return -ERANGE;
switch (mtd->oobsize) {
case 64:
oobregion->offset = 40;
break;
case 128:
oobregion->offset = 80;
break;
default:
return -EINVAL;
}
oobregion->length = ecc->total;
if (oobregion->offset + oobregion->length > mtd->oobsize)
return -ERANGE;
return 0;
}
static int nand_ooblayout_free_lp_hamming(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
int ecc_offset = 0;
if (section < 0 || section > 1)
return -ERANGE;
switch (mtd->oobsize) {
case 64:
ecc_offset = 40;
break;
case 128:
ecc_offset = 80;
break;
default:
return -EINVAL;
}
if (section == 0) {
oobregion->offset = 2;
oobregion->length = ecc_offset - 2;
} else {
oobregion->offset = ecc_offset + ecc->total;
oobregion->length = mtd->oobsize - oobregion->offset;
}
return 0;
}
const struct mtd_ooblayout_ops nand_ooblayout_lp_hamming_ops = {
.ecc = nand_ooblayout_ecc_lp_hamming,
.free = nand_ooblayout_free_lp_hamming,
};
static int check_offs_len(struct mtd_info *mtd,
loff_t ofs, uint64_t len)
{
......@@ -4559,7 +4627,7 @@ int nand_scan_tail(struct mtd_info *mtd)
break;
case 64:
case 128:
mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops);
mtd_set_ooblayout(mtd, &nand_ooblayout_lp_hamming_ops);
break;
default:
WARN(1, "No oob scheme defined for oobsize %d\n",
......
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