DT GPIO numbering?

[Linus Walleij]

On Mon, Aug 6, 2012 at 4:18 AM, Stephen Warren <swarren at wwwdotorg.org> wrote:

> I can't comment on the sysfs-vs-dev interface location, but I don't
> think it addresses Johannes' issue; finding out which GPIO IDs are
> provided by which devices.
>
> Perhaps in each device's sysfs node, there should be some information
> re: which GPIO range it provides. Right now, perhaps a text file with
> the GPIO base it it.

Yes that could work ...

> With the new /dev interface you mention above,
> perhaps a symlink to the /dev file, or a file containing the /dev file's
> major/minor number. Or, is there such a thing already (other than
> debugfs's gpio file).

Nothing I know of, but yes the day we come up with something,
it needs to be backward-compatible some way.

The problem is that there is really no reference userspace
like "lsgpio" or so. Maybe the first step could be to create that.

Yours,
Linus Walleij