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Date: Wed, 15 Aug 2012 17:31:16 +0300
From: Shmulik Ladkani <shmulik.ladkani@gmail.com>
To: dedekind1@gmail.com
Subject: Re: [PATCH 8/8] mtd: nand: use ECC, if present, when scanning OOB
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Hi Artem,

On Wed, 15 Aug 2012 15:05:17 +0300 Artem Bityutskiy <dedekind1@gmail.com> wrote:
> On Fri, 2012-06-22 at 16:35 -0700, Brian Norris wrote:
> > scan_read_raw_oob() is used in only in places where the MTD_OPS_PLACE_OOB
> > mode is preferable MTD_OPS_RAW mode, so use MTD_OPS_PLACE_OOB instead.
> > MTD_OPS_PLACE_OOB provides the same functionality with the potential[1]
> > added bonus of error correction.
> 
> Amended the commit message to satisfy Smulik's request, and pushed to
> l2-mtd.git, thanks Brian!

I had some second thoughts WRT the move from MTD_OPS_RAW to
MTD_OPS_PLACE_OOB.

When reading BBT content, MTD_OPS_PLACE_OOB is preferred.

But when scanning the OOBs for BBMs (when creating the table), I guess
MTD_OPS_RAW should be used - since manufacturer bad blocks are not
protected by ECC (as Matthieu noted in [1], and I elaborated in [2]).

Can you please review and comment regarding the ideas discussed there?

Thanks,
Shmulik

[1]
http://thread.gmane.org/gmane.linux.drivers.mtd/42243/focus=42365
[2]
http://thread.gmane.org/gmane.linux.drivers.mtd/42243/focus=42669