Re: [PATCH v2 5/5] spi: s3c64xx: use unsigned type for fifo handling variables

From: Andi Shyti
Date: Tue Jul 05 2016 - 11:01:30 EST


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