8.3 PXP add zephyr support

[faxe1008]

This patch adds the guarded definition of the semaphore required for the PXP implementation to work within zephyr.

Credit to @dberlin who originally authored this change.

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Credit to @dberlin who originally authored this commit.

[faxe1008]

The formatting within CI fails in code areas that I did not touch, I'd be happy to add a patch for this if required to move this forward :^)

[kisvegabor]

Great, thanks! I'll take care of the failing CI separately.

In v9 we have built in support for some RTOS-es. Would you be interested in adding a Zephyr port too?

In v9 we also have an stdlib wrapper which also might be interesting for Zephyr.

[dberlin]

Great, thanks! I'll take care of the failing CI separately.

In v9 we have built in support for some RTOS-es. Would you be interested in adding a Zephyr port too?

In v9 we also have an stdlib wrapper which also might be interesting for Zephyr.

I would believe you can use the pthread port in v9, with the right zephyr config options, but i haven't tried it. Wanted to get it all working first, didn't want to try to import v9 into zephyr to do it :)

I'll take a look when i get a chance.

Note: Zephyr is also working on c11 thread support (https://en.cppreference.com/w/c/thread), and is going to use that to support C++ threading/atomics/etc as well.

I imagine that (or pthreads) is the "right" path forward for ~all OSen here, including Zephyr, for this use case.

I also have vglite support for zephyr coming as well, which is more complex (zephyr we use events instead of O(n) semaphores like the FreeRTOS implementation), but you could, at a baseline, use pthreads/c11 there as well.

[faxe1008]

Thanks for the quick response @kisvegabor 👍 .

I am currently working also on updating our fork to v9.0, but i am facing some Zephyr specific build issues. Regarding the OSAL for Zephyr: I have a patch for this ready, however currently all zephyr specific glue code is part of our main repository. If we decide to upstream this to LVGL directly we will do this for everything (memory management, OSAL) at once.

I know that your current focus is bugfixing v9.0, but I am interested in whether or not you plan a 8.3 release in the near future? This would be pretty neat since alongside this current PR, this would allow us to merge zephyrproject-rtos/zephyr#68254.

Regards,
Fabian

[kisvegabor]

If we decide to upstream this to LVGL directly we will do this for everything (memory management, OSAL) at once.

Having all would great from LVGL's point of view. 😊

I am interested in whether or not you plan a 8.3 release in the near future?

Yes, see here: #5843