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authorAlexander Couzens <lynxis@fe80.eu>2017-05-02 12:19:00 +0200
committerBrian Norris <computersforpeace@gmail.com>2017-05-03 03:56:39 +0200
commit6a623e07694437ad09f382a13f76cffc32239a7f (patch)
treeb189b4914fdc96540f99082f04ba9e94c3689e40 /drivers/mtd
parentmtd: oxnas_nand: Allocating more than necessary in probe() (diff)
downloadlinux-6a623e07694437ad09f382a13f76cffc32239a7f.tar.xz
linux-6a623e07694437ad09f382a13f76cffc32239a7f.zip
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: 41b207a70d3a ("mtd: nand: implement the default mtd_ooblayout_ops") Cc: <stable@vger.kernel.org> Signed-off-by: Alexander Couzens <lynxis@fe80.eu> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Diffstat (limited to 'drivers/mtd')
-rw-r--r--drivers/mtd/nand/nand_base.c70
1 files changed, 69 insertions, 1 deletions
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index ed49a1d634b0..d474378ed810 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -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",