From mboxrd@z Thu Jan  1 00:00:00 1970
From: computersforpeace@gmail.com (Brian Norris)
Date: Sat, 13 Sep 2014 10:38:41 -0700
Subject: [PATCH] mtd: nand: gpmi: add proper raw access support
In-Reply-To: <20140913153622.GA10132@localhost.localdomain>
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Message-ID: <20140913173841.GA18093@brian-ubuntu>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Sat, Sep 13, 2014 at 11:36:24PM +0800, Huang Shijie wrote:
> On Fri, Sep 12, 2014 at 02:30:50PM +0200, Boris BREZILLON wrote:
> > This test validates what's returned by ecc_strength file in sysfs
> > (which in turn is specified by the NAND controller when initializing
> > the NAND chip).
> > 
> > Doing this should not imply knowing the ECC algorithm in use in the
> > NAND controller or the layout used to store data on NAND.
> the difficulty is that the ECC parity area can be not byte aligned.

Is there a problem with just rounding up to the nearest byte alignment
and ignoring the few bits that are wasted?

> As I ever said, it is hard to implement the two hooks.

"Hard" doesn't mean we shouldn't. I really would like to encourage more
NAND drivers to be programmed against the expected MTD behavior -- that
(if possible with the given hardware) they can pass the MTD tests
(drivers/mtd/tests/*).

Brian