[Core][Bugfix] Joystick: Ignore axis-related code when axes count=0

[amrsoll]

The analog joystick feature does not compile accross all platforms (see #4226 (review))

All joystick related code is put between #if JOYSTICK_AXES_COUNT > 0

This also reduces the size of the compiled code when you only want to use joystick buttons.

How to reproduce bug:

1. qmk new-keyboard
2. select the MCU GD32VF103 (other options don't matter)
3. rules.mk Add JOYSTICK_ENABLE = yes
4. config.h : Add

   #define JOYSTICK_BUTTON_COUNT 1
   #define JOYSTICK_AXES_COUNT 0

5. (optional) Change a key to JS_BUTTON0 in keymap
6. run qmk compile against new keyboard

Errors will show related to the ADC.

Disclaimer

1. I do not have the proper HW to debug on all keyboards, but it does work from the RP2040 branch which has a similar problem
   TBH, I'm mostly submitting this PR because it allows me to 🙈 on the bug I described in [Core] Add Raspberry Pi RP2040 support #14877 (comment)
2. I guess ifeq ($(shell expr $(JOYSTICK_AXES_COUNT) \> 0), 1) ain't so pretty,
   but it didn't work with #ifneq ($(JOYSTICK_AXES_COUNT), 0) ??
3. I have not been able to test if it actually broke the joystick (axis) feature, but I really can't see how it would.

Description

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Keyboard (addition or update)
• Keymap/layout/userspace (addition or update)
• Documentation

Issues Fixed or Closed by This PR

None

Checklist

• My code follows the code style of this project: C, Python
• I have read the PR Checklist document and have made the appropriate changes.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).

[zvecr]

The savePinState/restorePinState logic is due to be removed, which would supersede this fix.

(Also im fairly certain this wont work, as JOYSTICK_AXES_COUNT will not be available due to it being specified in config.h)

[amrsoll]

I am looking forward to that! The logic in the joystick parts are a bit confusing to me. Where can I find references to that reformatting, either in plans or in PRs?

[amrsoll]

Do you mean it won't work in common_features.mk ?

[fauxpark]

JOYSTICK_AXES_COUNT is a C preprocessor define, not a makefile variable, so it will not be visible at that level.

[amrsoll]

Then I guess it ain't possible to make that work unless we start defining the number of axis in rules.mk .. Is that advisable?

[fauxpark]

The change doesn't really make much sense anyway as you can configure axes to not read from the ADC with JOYSTICK_AXIS_VIRTUAL - having a count of 0 is not a good metric for whether or not to compile the ADC code.

[zvecr]

Is that advisable

Nope, should remain config.h only at the moment.

As I mention, 9a86f5c the code causing this issue is going shortly so I dont think we need to go forward with the proposed changes right now.

[amrsoll]

having a count of 0 is not a good metric for whether or not to compile the ADC code.

It is only avoiding compilation of ADC code for the joystick, as the joystick only uses it for reading analog axes. Doesn't prohibit other features from using the ADC.

As I mention, 9a86f5c the code causing this issue is going shortly so I dont think we need to go forward with the proposed changes right now.

Which branch is it part of? GitHub isn't tracking it anymore (rebased) and I can't find it through search

---

Perhaps the joystick buttons should be removed in favour of using programmable buttons? I am trying to use both, but they step on each others toes when trying to use with a flight simulator 🙄

[amrsoll]

Closing as recommended.

[amrsoll]

you can configure axes to not read from the ADC

@fauxpark True, but it still tries to compile it, which can break, unless you explicit that the driver is digital, which is a workaround and shouldn't be considered solid because it requires to understand the mechanisms behind.

This PR was aimed at people trying to make a keymap using joystick buttons but no axis, which is indeed particular.