altera_nios2 support decision required

[pabigot]

Due to lack of support the gpio driver for altera_nios2 is expected to be removed in about two weeks when 2.1 completes feature freeze.

It seems like that removing the GPIO driver will means the target platform should also be removed. Probably sooner rather than later.

What's going to be done about this?

[dleach02]

@carlescufi , @galak

[galak]

So I think there are 2 issues here. One is a question if altera_nios2 platform (soc, board, etc) is deprecated. I think @nashif is probably the best person to comment on that.

the second issue I see is how do we actually handle that deprecation, in light of an API change like GPIO. Our normal deprecation policy is 2 releases, not sure we have a clear answer for this situation. (Thus me marking it TSC).

[andrewboie]

We had the nios 2 arch port in tree for a considerable time before the GPIO driver appeared. Why not just drop the driver instead of the entire arch port?

[pabigot]

Most of the boards I've dealt with need GPIO for one thing or another (like LEDs), but if it's unnecessary for this platform that'd be fine. I just didn't want to get to the point where the driver suddenly disappears and nobody was ready for the fallout.

[andrewboie]

I think removing the entire arch port will not decrease the fallout of removing the GPIO driver for Nios II.

[pabigot]

A note for any TSC discussion: the same issue applies to the cc2650 platform (for which recent interest has been expressed). Can it stay (without GPIO support), or should it go?

Unlike (apparently) nios2 this is real hardware, and I'd be pretty annoyed if I saw it was listed as a supported platform but then later found out I couldn't use the buttons or LEDs.

(And the pcal9535a external GPIO chip, which may be less important, is also slated for removal without deprecation.)

[andrewboie]

Unlike (apparently) nios2 this is real hardware,

The Nios II port runs on the Altera Max10 board, which unless I'm hallucinating is real hardware

I'd be pretty annoyed if I saw it was listed as a supported platform but then later found out I couldn't use the buttons or LEDs.

I really can't understand where you're coming from. Removing the platform completely is somehow better than supporting the platform with the caveat that they might have to write a GPIO driver??

[nashif]

fixed in #20214