Re: [PATCH] atmel_spi: support zero length transfer (resend)

[Haavard Skinnemoen]

Atsushi Nemoto <anemo@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx>
> ---
> 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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