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mtd: kill MTD_NAND_VERIFY_WRITE

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Just as Artem suggested:

"Both UBI and JFFS2 are able to read verify what they wrote already.
There are also MTD tests which do this verification. So I think there
is no reason to keep this in the NAND layer, let alone wasting RAM in
the driver to support this feature. Besides, it does not work for sub-pages
and many drivers have it broken. It hurts more than it provides benefits."

So kill MTD_NAND_VERIFY_WRITE entirely.

Signed-off-by: Huang Shijie <shijie8@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Huang Shijie
2012-08-14 22:38:45 -04:00
committed by David Woodhouse
parent 8da28681eb
commit 657f28f881
26 changed files with 0 additions and 550 deletions
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53
drivers/mtd/nand/nand_base.c
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@@ -242,25 +242,6 @@ static void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
buf[i] = readb(chip->IO_ADDR_R);
}
/**
* nand_verify_buf - [DEFAULT] Verify chip data against buffer
* @mtd: MTD device structure
* @buf: buffer containing the data to compare
* @len: number of bytes to compare
*
* Default verify function for 8bit buswidth.
*/
static int nand_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
{
int i;
struct nand_chip *chip = mtd->priv;
for (i = 0; i < len; i++)
if (buf[i] != readb(chip->IO_ADDR_R))
return -EFAULT;
return 0;
}
/**
* nand_write_buf16 - [DEFAULT] write buffer to chip
* @mtd: MTD device structure
@@ -300,28 +281,6 @@ static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
p[i] = readw(chip->IO_ADDR_R);
}
/**
* nand_verify_buf16 - [DEFAULT] Verify chip data against buffer
* @mtd: MTD device structure
* @buf: buffer containing the data to compare
* @len: number of bytes to compare
*
* Default verify function for 16bit buswidth.
*/
static int nand_verify_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
{
int i;
struct nand_chip *chip = mtd->priv;
u16 *p = (u16 *) buf;
len >>= 1;
for (i = 0; i < len; i++)
if (p[i] != readw(chip->IO_ADDR_R))
return -EFAULT;
return 0;
}
/**
* nand_block_bad - [DEFAULT] Read bad block marker from the chip
* @mtd: MTD device structure
@@ -2120,16 +2079,6 @@ static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
status = chip->waitfunc(mtd, chip);
}
#ifdef CONFIG_MTD_NAND_VERIFY_WRITE
/* Send command to read back the data */
chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
if (chip->verify_buf(mtd, buf, mtd->writesize))
return -EIO;
/* Make sure the next page prog is preceded by a status read */
chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
#endif
return 0;
}
@@ -2804,8 +2753,6 @@ static void nand_set_defaults(struct nand_chip *chip, int busw)
chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
if (!chip->read_buf)
chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
if (!chip->verify_buf)
chip->verify_buf = busw ? nand_verify_buf16 : nand_verify_buf;
if (!chip->scan_bbt)
chip->scan_bbt = nand_default_bbt;