From 9c9d709965385de5a99f84b14bd5860e1541729e Mon Sep 17 00:00:00 2001
From: Paul Cercueil <paul@crapouillou.net>
Date: Sat, 16 Oct 2021 14:22:25 +0100
Subject: [PATCH] mtd: rawnand: davinci: Avoid duplicated page read
Git-commit: 9c9d709965385de5a99f84b14bd5860e1541729e
Patch-mainline: v5.17-rc1
References: git-fixes

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@vger.kernel.org> # v5.2
Fixes: a0ac778eb82c ("mtd: rawnand: ingenic: Add support for the JZ4740")
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20211016132228.40254-2-paul@crapouillou.net
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/mtd/nand/raw/davinci_nand.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/davinci_nand.c b/drivers/mtd/nand/raw/davinci_nand.c
index 89de24d3bb7a..2e6a0c1671be 100644
--- 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_oob_first(struct nand_chip *chip,
 	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;
 
-- 
2.31.1