Re: [PATCH 7/7] hw/misc/mps2-fpgaio: Implement push-buttons

[Peter Maydell <peter.maydell@linaro.org>]

On Tue, 16 Jun 2020 at 11:40, Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
> On 6/16/20 12:27 PM, Peter Maydell wrote:
> > This change seems kind of pointless unless these GPIO lines are
> > actually wired up to something.
>
> Yes, I should have kept it out of this series, or documented
> better the goal in the cover.
>
> I'm setting the roots to motivate a team of developers to
> work on a visualization of the MPS2 board. The push-button is
> supported by Zephyr, so the the idea is the visualizer generates
> QMP GPIO event to be processed such in pca9552_set_led(), and
> interact with the guest firmware.

I think that having a framework so we can better model this kind
of push button / LED / similar thing is definitely good. I just
think we need to review it at the framework level first -- it
might turn out that actually the right way to wire up the push
button to the UI framework isn't with a GPIO wire at all.
Similarly with the other patchset that sends QMP events for
LEDs -- that also seems like it's half of a design and a bit
awkward to review without the context for what it connects to.

thanks
-- PMM