Re: [RFC] gpio: expose pull-up/pull-down line flags to userspace

[Drew Fustini <pdp7pdp7@xxxxxxxxx>]

On Mon, Sep 23, 2019 at 10:38 AM Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
> I remember discussing it with Linus some time ago. This may not be as
> straightforward as simply adding new flags. Since PULL-UP/DOWN
> resistors can - among other parameters - also have configurable
> resistance, we'll probably need some kind of a structure for this
> ioctl() to pass any additional information to the kernel. Since we
> can't change ABI this may require adding a whole new ioctl() for
> extended configuration. This in turn has to be as future-proof as
> possible - if someone asks for user-space-configurable drive-strength,
> the new ioctl() should be ready for it.

Thanks for the insight, Bartosz.  Would you be able to point me to the
discussion if is available in an archive?  I would like to improve my
understanding.

What do you think of adding pull-up/down flags first, and then
implementing the extended configuration ioctl() later if necessary?

Thank you,
Drew