[PATCH 5.10 012/563] mtd: rawnand: davinci: Avoid duplicated page read

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 15:00:30 EST


From: Paul Cercueil <paul@xxxxxxxxxxxxxxx>

commit 9c9d709965385de5a99f84b14bd5860e1541729e upstream.

The function nand_davinci_read_page_hwecc_oob_first() first reads the
OOB data, extracts the ECC information, programs the ECC hardware before
reading the actual data in a loop.

Right after the OOB data was read, it called nand_read_page_op() to
reset the read cursor to the beginning of the page. This caused the
first page to be read twice: in that call, and later in the loop.

Address that issue by changing the call to nand_read_page_op() to
nand_change_read_column_op(), which will only reset the read cursor.

Cc: <stable@xxxxxxxxxxxxxxx> # v5.2
Fixes: a0ac778eb82c ("mtd: rawnand: ingenic: Add support for the JZ4740")
Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Link: https://lore.kernel.org/linux-mtd/20211016132228.40254-2-paul@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mtd/nand/raw/davinci_nand.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/mtd/nand/raw/davinci_nand.c
+++ b/drivers/mtd/nand/raw/davinci_nand.c
@@ -401,7 +401,8 @@ static int nand_davinci_read_page_hwecc_
if (ret)
return ret;

- ret = nand_read_page_op(chip, page, 0, NULL, 0);
+ /* Move read cursor to start of page */
+ ret = nand_change_read_column_op(chip, 0, NULL, 0, false);
if (ret)
return ret;