Re: [PATCH 1/2] i2c: tegra: Maintain CPU endianness

[Dmitry Osipenko]

22.01.2015 10:55, Alexandre Courbot ÐÐÑÐÑ:
> On Thu, Jan 22, 2015 at 4:40 PM, Thierry Reding
> <thierry.reding@xxxxxxxxx> wrote:
> > Should this not technically be le32_to_cpu() since the data originates
> > from the I2C controller?

No, i2c_readl returns value in CPU endianness, so it's correct. But for 
i2c_writel should be used le32_to_cpu(), since it takes value in CPU endianness.
It's my overlook, V2 is coming.

> > Why does this have to be initialized to 0 now?
>
> I suspect this is because we are going to memcpy less than 4 bytes
> into it, but I cannot figure out how that memcpy if guaranteed to
> produce the expected result for both endiannesses.
That's correct. Memcpy is working with bytes, so it doesn't care about 
endianness and produces expected result, since I2C message is char array.

--
Dmitry
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