QMK Breaking Change - 2020 Feb 29 Changelog

Four times a year QMK runs a process for merging Breaking Changes. A Breaking Change is any change which modifies how QMK behaves in a way that is incompatible or potentially dangerous. We limit these changes to 4 times per year so that users can have confidence that updating their QMK tree will not break their keymaps.

Update ChibiOS/ChibiOS-Contrib/uGFX submodules

• General Notes
  • A make git-submodule may be required after pulling the latest QMK firmware code to update affected submodules to the upgraded revisions
  • Enabling link-time-optimization (LINK_TIME_OPTIMIZATION_ENABLE = yes) should work on a lot more boards
• Upgrade to ChibiOS ver19.1.3
  • This will allow QMK to update to upstream ChibiOS a lot easier -- the old version was ~2 years out of date. Automated update scripts have been made available to simplify future upgrades.
  • Includes improved MCU support and bugfixes
  • ChibiOS revision is now included in Command output
  • Timers should now be more accurate
• Upgrade to newer ChibiOS-Contrib
  • Also includes improved MCU support and bugfixes
  • ChibiOS-Contrib revision is now included in Command output
• Upgrade to newer uGFX
  • Required in order to support updated ChibiOS

Fix ChibiOS timer overflow for 16-bit SysTick devices

• On 16-bit SysTick devices, the timer subsystem in QMK was incorrectly dealing with overflow.
  • When running at a 100000 SysTick frequency (possible on 16-bit devices, but uncommon), this overflow would occur after 0.65 seconds.
• Timers are now correctly handling this overflow case and timing should now be correct on ChibiOS/ARM.

Update LUFA submodule

• Updates the LUFA submodule to include updates from upstream (abcminiuser/lufa)
• Includes some cleanup for QMK DFU generation

Encoder flip

• Flips the encoder direction so that clockwise == true is for actually turning the knob clockwise
• Adds ENCODER_DIRECTION_FLIP define, so that reversing the expected direction is simple for users.
• Cleans up documentation page for encoders

Adding support for BACKLIGHT_ON_STATE for hardware PWM backlight

• Previously, the define only affected software PWM, and hardware PWM always assumed an N-channel MOSFET.
• The hardware PWM backlight setup has been updated to respect this option.
• The default "on" state has been changed to 1 - this impacts all keyboards using software PWM backlight that do not define it explicitly. If your keyboard's backlight is acting strange, it may have a P-channel MOSFET, and will need to have #define BACKLIGHT_ON_STATE 0 added to the keyboard-level config.h. Please see the PR for more detailed information.

Migrating ACTION_LAYER_TAP_KEY() entries in fn_actions to LT() keycodes

• fn_actions is deprecated, and its functionality has been superseded by direct keycodes and process_record_user()
• The end result of removing this obsolete feature should result in a decent reduction in firmware size and code complexity
• All keymaps affected are recommended to switch away from fn_actions in favour of the custom keycode and macro features

Moving backlight keycode handling to process_keycode/

• This refactors the backlight keycode logic to be clearer and more modular.
• All backlight-related keycodes are now actioned in a single file.
• The ACTION_BACKLIGHT_* macros have also been deleted. If you are still using these in a fn_actions[] block, please switch to using the backlight keycodes or functions directly.

Refactor Planck keymaps to use Layout Macros

• Refactor Planck keymaps to use layout macros instead of raw matrix assignments
• Makes keymaps revision-agnostic
• Should reduce noise and errors in Travis CI logs

GON NerD codebase refactor

• Splits the codebase for GON NerD 60 and NerdD TKL PCBs into two separate directories.
• If your keymap is for a NerD 60 PCB, your make command is now make gon/nerd60:<keymap>.
• If your keymap is for a NerD TKL PCB, your make command is now make gon/nerdtkl:<keymap>.