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Date: Thu, 22 Jun 2017 14:26:06 -0700
From: Brian Norris <computersforpeace@gmail.com>
To: Boris Brezillon <boris.brezillon@free-electrons.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>,
 David Woodhouse <dwmw2@infradead.org>, Marek Vasut <marek.vasut@gmail.com>,
 Richard Weinberger <richard@nod.at>,
 Cyrille Pitchen <cyrille.pitchen@wedev4u.fr>,
 linux-mtd@lists.infradead.org, Kyungmin Park <kyungmin.park@samsung.com>
Subject: Re: [PATCH] mtd: Fallback to ->_read/write_oob() when
 ->_read/write() is missing
Message-ID: <20170622212606.GF14148@google.com>
References: <20170611204255.18622-1-boris.brezillon@free-electrons.com>
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On Sun, Jun 11, 2017 at 10:42:55PM +0200, Boris Brezillon wrote:
> Some MTD sublayers/drivers are implementing ->_read/write_oob() and
> providing dummy wrappers for their ->_read/write() implementations.
> Let the core handle this case instead of duplicating the logic.
> 
> Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> ---
> Note that the goldfish_nand driver (currently in staging) has not been
> updated because some the ops->len != mtd->writesize check done in
> goldfish_nand_read/write_oob() prevents us from using this function as
> a fallback for ->_read/write().
> 
> This behavior is buggy anyway, because the core expects drivers
> implementing ->_read_oob() to support reading more than ->writesize in
> a single call. Probably something we should fix.

Looks OK to me:

Acked-by: Brian Norris <computersforpeace@gmail.com>

This touches NAND drivers more than core MTD stuff, so feel free to take
it in your branch.