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Date: Wed, 6 Jul 2016 00:01:21 +0900
From: Andi Shyti <andi@etezian.org>
To: Mark Brown <broonie@kernel.org>
Cc: Andi Shyti <andi.shyti@samsung.com>, Kukjin Kim <kgene@kernel.org>,
        Krzysztof Kozlowski <k.kozlowski@samsung.com>,
        Jaehoon Chung <jh80.chung@samsung.com>,
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        linux-samsung-soc@vger.kernel.org, linux-spi@vger.kernel.org,
        linux-kernel@vger.kernel.org, Andi Shyti <andi@etezian.org>
Subject: Re: [PATCH v2 5/5] spi: s3c64xx: use unsigned type for fifo handling
 variables
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Hi Mark,

> > The 'quirks' variable cannot ever be negative, therefore use u8
> > instead of int. The 8 bit size is given from the fact that
> > currently the quirks variable has very few statuses.
> > 
> > The rx_lvl_offset and tx_st_done store shift values, so that u8
> > is a proper size.
> > 
> > fifo_lvl_mask stores a series of masks, to be in we will keep the
> > 32 bit size.
> 
> What's the advantage of these changes?  This feels like microptimisation
> of something that shouldn't be a big performance issue and it's not
> always the case that the compiler does something more sensible with
> smaller or unsigned types.  I'm not saying don't do it, I'm just saying
> that it's not clear to me what the win is.

not much indeed. Just something that was a little bothering me
while I was reading through.

Please, feel free to drop it.

Thanks,
Andi