Date: Sat, 29 Mar 2008 17:56:51 +0100
From: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
To: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: David Brownell <david-b@pacbell.net>,
       spi-devel-general@lists.sourceforge.net, linux-kernel@vger.kernel.org,
       akpm@linux-foundation.org, marc.pignat@hevs.ch, nforrester@whoi.edu
Subject: Re: [PATCH] atmel_spi: support zero length transfer (resend)
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Atsushi Nemoto <anemo@mba.ocn.ne.jp> wrote:
> A spi transfer with zero length is not invalid.  For example, such
> transfer (len == 0 && delay_usecs != 0) can be used to achieve delay
> before first CLK edge after chipselect assertion.
> 
> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
> ---
> Though some discussion about zero length transfer were raised by this
> patch last time, I think there were no explicit objection to this
> patch itself.

Well, the patch doesn't seem to do any harm, but I can't see much of a
point to it either if zero-length transfers aren't going to be
allowed...

Also, if the length is zero, the driver will end up doing a memset with
length zero at some point. Is that allowed?

Haavard
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