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Date: Mon, 02 Apr 2012 10:34:12 -0700
From: Mike Dunn <mikedunn@newsguy.com>
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To: Brian Norris <computersforpeace@gmail.com>
Subject: Re: [PATCH 2/4] MTD: flash drivers set ecc strength
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Cc: Ivan Djelic <ivan.djelic@parrot.com>, linux-mtd@lists.infradead.org,
 David Woodhouse <David.Woodhouse@intel.com>,
 Artem Bityutskiy <dedekind1@gmail.com>
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Brian,

I was just reviewing things and realized that I accidentally ignored one of your
comments...


On 03/29/2012 10:24 AM, Brian Norris wrote:
>>
>>        case NAND_ECC_SOFT_BCH:
>> @@ -3384,6 +3385,8 @@ int nand_scan_tail(struct mtd_info *mtd)
>>                        pr_warn("BCH ECC initialization failed!\n");
>>                        BUG();
>>                }
>> +               chip->ecc.strength =
>> +                       chip->ecc.bytes*8 / fls(8*chip->ecc.size);
> 
> Isn't this spacing against coding style? I'd suggest spaces around the
> '*'. Also, after a few minutes, I have no idea where this calculation
> comes from. But I'm not familiar with SOFT_BCH. Maybe a comment is in
> order?


I'm no bch expert myself (ping, Ivan), but I believe this is correct, and it is
consistant with the equations used to determine the 't' parameter (i.e.,
ecc_strength) from nand_bch_init() in drivers/mtd/nand/nand_bch.c.  (BTW,
currently only nandsim uses SOFT_BCH.)  As for coding style... honestly, I
mostly just rely on checkpatch.pl, but I'll check the style guide document.

Thanks,
Mike