[U-Boot] [PATCH 1/2 v4] ARM : Add GPIO Driver and IOMUX definition for S3C2440

[Scott Wood <scottwood@freescale.com>]

On 05/02/2012 01:16 AM, Minkyu Kang wrote:
> Dear Marek,
> 
> On 2 May 2012 11:44, Marek Vasut <marex@denx.de> wrote:
>>>> +int gpio_set_value(unsigned gpio, int value)
>>>> +{
>>>> +       unsigned l = readl(GPIO_FULLPORT(gpio));
>>>> +       unsigned port = GPIO_FULLPORT(gpio);
>>>> +
>>>> +       /*
>>>> +        * All GPIO Port have a configuration on
>>>> +        * 2 bits excepted the first GPIO (A) which
>>>> +        * have only 1 bit of configuration.
>>>> +        */
>>>> +       if (value)
>>>> +               if (!GPIO_PORT(gpio))
>>>> +                       l |= (0x1 << GPIO_BIT(gpio));
>>>> +               else
>>>> +                       l |= (0x3 << GPIO_BIT(gpio));
>>>> +       else
>>>> +               if (!GPIO_PORT(gpio))
>>>> +                       l &= ~(0x1 << GPIO_BIT(gpio));
>>>> +               else
>>>> +                       l &= ~(0x3 << GPIO_BIT(gpio));
>>>
>>> Need brace at this if..else statement.
>>
>> I wanted to ask why, but ... C isn't python, good point ;-)
> 
> As I know, it's a rule of u-boot.. maybe. :)

It is a U-Boot rule (multi-line if/loop body), and also it's good to
avoid the ambiguous "if/if/else" construct, but wouldn't this be better as:

if (GPIO_PORT(gpio))
	bit = 1 << GPIO_BIT(gpio);
else
	bit = 3 << GPIO_BIT(gpio);

if (value)
	l |= bit;
else
	l &= ~bit;

?

-Scott