[RFC PATCH 2/3] pinctrl: imx: add pinmux-imx53 support

On Tue, Dec 6, 2011 at 8:33 AM, Lothar Wa?mann [off-list ref] wrote:

Shawn Guo writes:

quoted

On Mon, Dec 05, 2011 at 10:18:38PM +0100, Sascha Hauer wrote:

quoted

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This brings me to the point that currently we have the pins described as

#define MX53_PAD_<name>__<function>

But that's also the reason why we have so many lengthy iomux-mx*.h on
imx. ?Taking iomux-mx53.h for example, it's a 109K header with 1219
LOC, but probably only 10% of the definitions will actually be used.

Which has the benefit of having correct pin definitions for everyone
to use. If developers who need to use currently unused pindefs have to
create them on their own, there will always be a good chance in
getting them wrong.

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which means that you don't have to look into the datasheet to get the
different options for a pin

Looking at the datasheet when we write code is a pretty natural thing
to me.

The pindefs are like interrupt numbers or IO addresses for which there
also is a complete list of definitions in the kernel no matter whether
they are actually all in use.

In both cases I'd say it's not the business of the pin control
implementation to worry about size of .h files in arch/arm/*

Getting rid of such defines and board data is the business of the
device tree and nothing else, if I understand the way people are
thinking about this.

So I would prefer to keep these two concepts separate:
1) get something in place that integrates nicely with pinctrl
2) get device tree in place
3) get rid of old board files and huge .h define lists including
   I/O, irqs, pinmux lists...
4) ...
5) profit

So don't try to solve all things at once or you'll end up trying
to drink the ocean.

Yours,
Linus Walleij