Subject: [PATCH 1/2] ARM: i.MX6: set ARCH_NR_GPIO to 244

From: [email-masked] (Dirk Behme)
Date: Mon, 30 Jul 2012 13:14:48 +0200

On 30.07.2012 10:46, Shawn Guo wrote:
> On Mon, Jul 30, 2012 at 08:40:58AM +0200, Dirk Behme wrote:
>> - Do you like to propose a better macro than SOC_IMX6Q to cover
>> imx3/imx6, too?
>>
> No, I do not see the need of this.  CONFIG_ARCH_NR_GPIO is not the only
> way to overwrite the default number.  We can define ARCH_NR_GPIOS to
> the number we want in IMX platform headers.

I understood

http://lkml.indiana.edu/hypermail/linux/kernel/1111.0/01565.html

that the goal is to not use the headers any more. But I might have 
misunderstood that ...

>> - Do imx3 and imx5 have the same GPIO number like imx6? I.e. 7 banks
>> with 32 pins == 224 GPIOs?
>>
> imx31, imx35: 3 banks
> imx51: 4 banks
> imx53: 7 banks

Sounds like 7 is a good max number then, thanks!

>>> Looking at current users of this definition, you will find all of them
>>> are defining a number bigger than 256 for extending the maximum number.
>>> It might be a sign that having a gpio array which is a little bigger
>>> than necessary is not a concern on machines today.
>> Or it might be a sign that they *have* more than 256? I don't know.
> 
> Yes.  I was actually saying that there is no platforms defining the
> Kconfig symbol smaller than 256 to save the space.

Hmm, maybe they just have all more than 256 and we are the first with 
less? Anyway, I'm not sure why smaller/bigger should be important here. 
I would feel that the goal should be to configure the correct number if 
possible, independent of smaller/bigger.

Best regards

Dirk