Re: [PATCH 1/2] ARM: EXYNOS: add support GPIO for EXYNOS5250

[Sylwester Nawrocki <snjw23@gmail.com>]

On 02/02/2012 07:22 PM, Grant Likely wrote:
>>>   /* the end of the EXYNOS4 specific gpios */
>>>   #define EXYNOS4_GPIO_END	(EXYNOS4_GPZ(EXYNOS4_GPIO_Z_NR) + 1)
>>> -#define S3C_GPIO_END		EXYNOS4_GPIO_END
>>>
>>> -/* define the number of gpios we need to the one after the GPZ() range */
>>> -#define ARCH_NR_GPIOS		(EXYNOS4_GPZ(EXYNOS4_GPIO_Z_NR) +	\
>>> -				 CONFIG_SAMSUNG_GPIO_EXTRA + 1)
>>> +/* EXYNOS5 serise */
>>> +/* GPIO bank sizes */
>>> +#define EXYNOS5_GPIO_A0_NR	(8)
>>
>> nit: It's been always a mystery to me, what are the parentheses around the
>> numbers helpful for ? IMHO even if there is more things like this in
>> the file it might be better to skip extra parentheses here.
> 
> It protects against the preprocessor combining a macro with other code in
> unpredictable ways.  For example:
> 
> #define SIZE  10 + 20
> int i = SIZE * 5;
> 
> Without the parenthesis the result of i is 110, when the programmer would
> expect 150.

Right, I guess it's a fundamental requirement most people are aware about. 
Nevertheless my point were only single integers.

> For single integers like these, the parenthesis aren't actually necessary, but
> I given that for every other #define it is good practice, I don't object to
> seeing them on single integers also.

I respect that but I have a different opinion. :-) Those parentheses have 
always been bugging me, they decrease readability for virtually no benefit. 
They're more an aesthetic issue though so I wouldn't argue more about it. 
Just will try to get used, and I'll avoid them where possible. :-)

--
Regards,
Sylwester