From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Sun, 14 Aug 2011 10:11:39 +0200
From: Ivan Djelic <ivan.djelic@parrot.com>
To: Wolfram Sang <w.sang@pengutronix.de>
Subject: Re: GPMI-NAND Status?
Message-ID: <20110814081139.GD17063@parrot.com>
References: <20110805135133.GA26981@pengutronix.de>
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Cc: Koen Beel <koen.beel.barco@gmail.com>, Huang Shijie <b32955@freescale.com>,
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	Shawn Guo <shawn.guo@linaro.org>, "linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	Lothar =?utf-8?Q?Wa=C3=9Fmann?= <LW@KARO-electronics.de>
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On Fri, Aug 05, 2011 at 02:51:33PM +0100, Wolfram Sang wrote:
(...)
> 
> problem overwriting all-0xff data in NAND [2]
> =============================================
> 
> Although it occured only when writing JFFS2 images so far, this is a generic
> issue and needs to be fixed, right?
> 
> 
(...)
> [2] http://lists.infradead.org/pipermail/linux-mtd/2011-July/037104.html

As explained in the thread linked above, this issue should be fixed in your
flashing tool, _not_ in your driver. The nand device you are using does not
support programming pages multiple times in a row; pretending it does in the
special all-0xff case is inefficient (you need to detect all-0xff data) and
unnecessary (just do not program blank pages !).
BR,

Ivan