Commit 05e4fdd5 authored Jun 10, 2021 by Miquel Raynal Committed by Greg Kroah-Hartman Sep 22, 2021

dt-bindings: mtd: gpmc: Fix the ECC bytes vs. OOB bytes equation



[ Upstream commit 778cb8e39f6ec252be50fc3850d66f3dcbd5dd5a ]

"PAGESIZE / 512" is the number of ECC chunks.
"ECC_BYTES" is the number of bytes needed to store a single ECC code.
"2" is the space reserved by the bad block marker.

"2 + (PAGESIZE / 512) * ECC_BYTES" should of course be lower or equal
than the total number of OOB bytes, otherwise it won't fit.

Fix the equation by substituting s/>=/<=/.

Suggested-by: Ryan J. Barnett <ryan.barnett@collins.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/linux-mtd/20210610143945.3504781-1-miquel.raynal@bootlin.com


Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 3d95bdee

Documentation/devicetree/bindings/mtd/gpmc-nand.txt

+1 −1

Original line number	Diff line number	Diff line
		@@ -122,7 +122,7 @@ on various other factors also like;
		so the device should have enough free bytes available its OOB/Spare
		area to accommodate ECC for entire page. In general following expression
		helps in determining if given device can accommodate ECC syndrome:
		"2 + (PAGESIZE / 512) * ECC_BYTES" >= OOBSIZE"
		"2 + (PAGESIZE / 512) * ECC_BYTES" <= OOBSIZE"
		where
		OOBSIZE number of bytes in OOB/spare area
		PAGESIZE number of bytes in main-area of device page