[RFC 1/3] pinctrl: add a driver for NVIDIA Tegra

Linus Walleij linus.walleij at linaro.org
Fri Dec 9 18:55:58 EST 2011

On Fri, Dec 9, 2011 at 6:28 PM, Stephen Warren <swarren at nvidia.com> wrote:

> Hence, there's no point parsing it from device tree; we end up with exactly
> the same data in the driver, yet have spent a bunch of time parsing it out
> from device tree instead of just embedding it into the kernel binary.

For me there are two points:

- Avoiding clash with kernel maintainers who hate firmware-like tables and
  binary data filling up the kernel. Some certain other guy bearing my
  name comes to mind.

- Footprint: the majority of the stuff in your driver ends up in non-discardable
  memory, and will be kept around. Since we have this concept of a
  single zImage for a number of say ARMv7 systems, and since pin
  controllers can be pretty hard to load from modules, *all* of them
  may have to be compiled-in. If every driver for every board takes this
  approach I am afraid it will be end up with a measurable footprint.

Linus Walleij

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