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Subject: Re: [PATCH 1/1] mtd: eLBC NAND: fixes subpage write support
From: Scott Wood <scottwood@freescale.com>
To: Pekon Gupta <pekon@ti.com>
Date: Wed, 7 May 2014 18:22:53 -0500
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Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>,
 Brian Norris <computersforpeace@gmail.com>,
 linux-mtd <linux-mtd@lists.infradead.org>,
 Helmut Schaa <helmut.schaa@googlemail.com>
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On Tue, 2014-05-06 at 09:41 +0530, Pekon Gupta wrote:
> As subpage write is enabled by default for all drivers, nand_write_subpage_hwecc
> causes a crash if the driver did not register ecc->hwctl or ecc->calculate.
> This behavior was introduced in
>    commit 837a6ba4f3b6d23026674e6af6b6849a4634fff9
>    "mtd: nand: subpage write support for hardware based ECC schemes".
> 
> This fixes a crash by emulating subpage write support by padding sub-page data
> with 0xff on either sides to make it full page compatible.
> 
> CC: <stable@vger.kernel.org> # 3.10.x+
> 
> Reported-by: Helmut Schaa <helmut.schaa@googlemail.com>
> Tested-by: Helmut Schaa <helmut.schaa@googlemail.com>
> Signed-off-by: Pekon Gupta <pekon@ti.com>
> ---
>  drivers/mtd/nand/fsl_elbc_nand.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)

Reviewed-by: Scott Wood <scottwood@freescale.com>

-Scott