Re: [PATCH] gpio: keep the GPIO line names internal

[Johan Hovold <johan@kernel.org>]

On Mon, Oct 05, 2015 at 10:54:52AM +0200, Linus Walleij wrote:
> On Sun, Oct 4, 2015 at 3:37 PM, Johan Hovold <johan@kernel.org> wrote:
> 
> > This looks good (apart from the checkpatch warning for the warning
> > message string).
> 
> Yeah the GPIO maintainer is liberal about that rule...

Heh. I'm sticking to the 80 column limit too, but having grepable error
messages do have its merit.

> > You also need to revert ddd5404007b8 ("gpio-sysfs: Use gpio descriptor
> > name instead of gpiochip names array") however as this is an ABI change.
> > Otherwise pins with a name in DT will now be exported using the gpio name
> > rather than number as they used to be. [ The current behaviour is
> > maintained by exporting names from chip->names for hard coded names
> > only. ]
> 
> I think it is ABI-correct: it uses desc->name if that is set, and
> currently that is only set from chip->names[] so status quo.

Yes, but this work was aiming at generalising the hogs so that they
could later be requested (and exported), right?

This means that a pin used today from userspace, can not be initialised
using this mechanism without breaking the ABI.

My suggestion is to leave gpiolib-sysfs.c as is, and make sure to limit
the name export to legacy board files as before.

Thanks,
Johan