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Date: Tue, 5 Nov 2013 10:07:43 -0800
From: Brian Norris <computersforpeace@gmail.com>
To: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Subject: Re: [PATCH 0/1] Bad block markers here, there and everywhere
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Cc: Lior Amsalem <alior@marvell.com>,
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On Tue, Nov 05, 2013 at 09:00:20AM -0300, Ezequiel Garcia wrote:
> This commit adds a new option called NAND_BBT_DATA_BBM. The change itself
> is pretty small and simple to understand: when the badblock_pattern sets the
> NAND_BBT_DATA_BBM option, scan_block_fast() reads the data region instead
> of the OOB region.

I think this type of scanning method is better suited to a different
type of solution: implement a custom nand_chip.bad_block() call-back.
Unfortunately, nand_base/nand_bbt are kind of inconsistent, so that some
code paths use nand_chip.bad_block() and some use nand_bbt.c's scanning
code to check for bad block markers, so this is not currently a good
solution.

I've been meaning to follow through with an improved version of this
patch for a while:

  http://lists.infradead.org/pipermail/linux-mtd/2012-June/042571.html

Such a patch provides several benefits, one of them being that drivers
like yours can easily provide a custom BBM location. What do you think?

Brian