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Date: Thu, 19 Jul 2012 14:49:24 +0200
From: Sebastian Huber <sebastian.huber@embedded-brains.de>
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To: linux-mtd@lists.infradead.org
Subject: ARM: LPC32XX MLC NAND Bad Block Handling
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Hello,

it seems that the LPC32XX MLC NAND driver uses nand_default_block_markbad() to 
mark a block as bad.  This function will use nand_do_write_oob() with 
MTD_OPS_PLACE_OOB to write the bad block marker in the bad block itself.  This 
function will use chip->ecc.write_oob() to write the OOB which is

static int lpc32xx_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
			      int page)
{
	/* None, write_oob conflicts with the automatic LPC MLC ECC decoder! */
	return 0;
}

Does this mean that the bad block mark is only present in the bad block table?

I think the driver should set NAND_BBT_NO_OOB_BBM to make this clear.

-- 
Sebastian Huber, embedded brains GmbH

Address : Obere Lagerstr. 30, D-82178 Puchheim, Germany
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E-Mail  : sebastian.huber@embedded-brains.de
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