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| author | Maxim Levitsky <maximlevitsky@gmail.com> | 2010-02-22 20:39:38 +0200 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2010-02-26 18:02:07 +0000 |
| commit | e0b58d0a7005cd4b9c7fa4694a437a2d86719c13 (patch) | |
| tree | 24eef139ef7ab9d37125f9d508a6cf712155a20e | |
| parent | b64d39d8b03fea88417d53715ccbebf71d4dcc9f (diff) | |
| download | linux-e0b58d0a7005cd4b9c7fa4694a437a2d86719c13.tar.gz linux-e0b58d0a7005cd4b9c7fa4694a437a2d86719c13.tar.bz2 linux-e0b58d0a7005cd4b9c7fa4694a437a2d86719c13.zip | |
mtd: nand: add ->badblockbits for minimum number of set bits in bad block byte
This can be used to protect against bitflips in that field, but now mostly
for smartmedia.
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| -rw-r--r-- | drivers/mtd/nand/nand_base.c | 13 | ||||
| -rw-r--r-- | include/linux/mtd/nand.h | 1 |
2 files changed, 10 insertions, 4 deletions
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 51dfea1b3ce6..ba29a29bd743 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -364,14 +364,18 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip) bad = cpu_to_le16(chip->read_word(mtd)); if (chip->badblockpos & 0x1) bad >>= 8; - if ((bad & 0xFF) != 0xff) - res = 1; + else + bad &= 0xFF; } else { chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos, page); - if (chip->read_byte(mtd) != 0xff) - res = 1; + bad = chip->read_byte(mtd); } + if (likely(chip->badblockbits == 8)) + res = bad != 0xFF; + else + res = hweight8(bad) < chip->badblockbits; + if (getchip) nand_release_device(mtd); @@ -2884,6 +2888,7 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd, /* Set the bad block position */ chip->badblockpos = mtd->writesize > 512 ? NAND_LARGE_BADBLOCK_POS : NAND_SMALL_BADBLOCK_POS; + chip->badblockbits = 8; /* Get chip options, preserve non chip based options */ chip->options &= ~NAND_CHIPOPTIONS_MSK; diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index 48bc2c54302c..f2d4a1ac14b8 100644 --- a/include/linux/mtd/nand.h +++ b/include/linux/mtd/nand.h @@ -401,6 +401,7 @@ struct nand_chip { int subpagesize; uint8_t cellinfo; int badblockpos; + int badblockbits; flstate_t state; |