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Subject: RE: [PATCH] mtd: atmel_nand: fix access to 16 bit NAND devices
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Venu Byravarasu <vbyravarasu@nvidia.com>
Date: Fri, 03 Feb 2012 07:32:41 +0200
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On Fri, 2012-02-03 at 09:05 +0530, Venu Byravarasu wrote:
> I see a problem with atmel_read_buf16 & atmel_write_buf16 functions.
> As they are calling __raw_readsw & __raw_writesw respectively, which=20
> would cause panic in cases of 16 bit unaligned buffers.
> However, the buf passed to these functions is of type u8* from=20
> atmel_read_buf & atmel_write_buf functions.

I think this is a valid concern. In theory, the NAND infrustructure must
guarantee that the buffer is always of even length, and most probably it
does, but we could add a WARN_ON(len & 1) statements in
'atmel_read_buf()' and 'atmel_write_buf()'.

And probably the type could indeed be changed.

But these concerns should be addressed separately.

--=20
Best Regards,
Artem Bityutskiy

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