* Extensible split data sync capability through transactions.

- Split common transport has been split up between the transport layer
  and data layer.
- Split "transactions" model used, with convergence between I2C and
  serial data definitions.
- Slave matrix "generation count" is used to determine if the full slave
  matrix needs to be retrieved.
- Encoders get the same "generation count" treatment.
- All other blocks of data are synchronised when a change is detected.
- All transmissions have a globally-configurable deadline before a
  transmission is forced (`FORCED_SYNC_THROTTLE_MS`, default 100ms).
- Added atomicity for all core-synced data, preventing partial updates
- Added retries to AVR i2c_master's i2c_start, to minimise the number of
  failed transactions when interrupts are disabled on the slave due to
  atomicity checks.
- Some keyboards have had slight modifications made in order to ensure
  that they still build due to firmware size restrictions.

* Fixup LED_MATRIX compile.

* Parameterise ERROR_DISCONNECT_COUNT.

* ws2812: Fix number of nops for AVR at 8 MHz

When trying to calculate the number of nops for AVR running at 8 MHz,
the value of `w3` is expected to be negative; however, because `F_CPU`
is defined in tmk_core/avr.mk with the `UL` suffix, the preprocessor
performs its calculations using `unsigned long`, getting a very large
positive number instead of the expected negative number; this then
results in generating code with a huge number of nops.  Fix the broken
calculations by performing a comparison before subtraction, so that the
unsigned number wraparound does not occur.

The keyboard which triggers the problem is `handwired/promethium`; the
buggy code silently compiles, but the resulting timings would be
completely wrong.

* ws2812: Clean up the code after the 8 MHz fix

Remove old code which was unsuccessfully trying to clamp negative w1, w2
and w3 values to 0, and set w1_nops, w2_nops and w3_nops directly.

* at90usb162 support

* fix missing bracket

* Apply suggestions from code review

Co-authored-by: Ryan <fauxpark@gmail.com>

Co-authored-by: Ryan <fauxpark@gmail.com>

* Rewrite APA102 support

The APA102 source was broken by commit 16a15c1cfc as it did not include the
quantum header. This commit addresses that, as well as other issues with
transferring bytes over the SPI interface, i.e. it was not setting the
clock pin back to low after sending a bit.

The deviation when sending the end frame is kept, but updated to the
latest from the referenced project.

Finally, these changes expose the global LED brightness parameter
of the APA102. Brightness values are configurable through
`APA102_DEFAULT_BRIGHTNESS` and `APA102_MAX_BRIGHTNESS`.

* Fix typo in led brightness extern

* Move driver out of AVR directory and add delay for ARM

* Experimental APA102 support on AVR and ARM

Co-authored-by: Alde Rojas <hello@alde.io>

* Refactor apa102_send_byte() calls to a loop

* Implement io_wait function for ARM

* Move APA102 drivers to own directory, fix copyright notice

* Add APA102 keymap to handwired/onekey

* Simplify RGBLIGHT_ENABLE/DRIVER option handling

Co-authored-by: Mikkel Jeppesen <2756925+Duckle29@users.noreply.github.com>

Co-authored-by: Dimitris Papavasiliou <dpapavas@gmail.com>

* Branch point for 2020 November 28 Breaking Change                                                

* Remove matrix_col_t to allow MATRIX_ROWS > 32 (#10183)                                           

* Add support for soft serial to ATmega32U2 (#10204)                                               

* Change MIDI velocity implementation to allow direct control of velocity value (#9940)            

* Add ability to build a subset of all keyboards based on platform.                                

* Actually use eeprom_driver_init().                                                               

* Make bootloader_jump weak for ChibiOS. (#10417)                                                  

* Joystick 16-bit support (#10439)                                                                 

* Per-encoder resolutions (#10259)                                                                 

* Share button state from mousekey to pointing_device (#10179)                                     

* Add hotfix for chibios keyboards not wake (#10088)                                               

* Add advanced/efficient RGB Matrix Indicators (#8564)                                             

* Naming change.                                                                                   

* Support for STM32 GPIOF,G,H,I,J,K (#10206)                                                       

* Add milc as a dependency and remove the installed milc (#10563)                                  

* ChibiOS upgrade: early init conversions (#10214)                                                 

* ChibiOS upgrade: configuration file migrator (#9952)                                             

* Haptic and solenoid cleanup (#9700)                                                              

* XD75 cleanup (#10524)                                                                            

* OLED display update interval support (#10388)                                                    

* Add definition based on currently-selected serial driver. (#10716)                               

* New feature: Retro Tapping per key (#10622)                                                      

* Allow for modification of output RGB values when using rgblight/rgb_matrix. (#10638)             

* Add housekeeping task callbacks so that keyboards/keymaps are capable of executing code for each main loop iteration. (#10530)

* Rescale both ChibiOS and AVR backlighting.                                                       

* Reduce Helix keyboard build variation (#8669)                                                    

* Minor change to behavior allowing display updates to continue between task ticks (#10750)        

* Some GPIO manipulations in matrix.c change to atomic. (#10491)                                   

* qmk cformat (#10767)                                                                             

* [Keyboard] Update the Speedo firmware for v3.0 (#10657)                                          

* Maartenwut/Maarten namechange to evyd13/Evy (#10274)                                             

* [quantum] combine repeated lines of code (#10837)                                                

* Add step sequencer feature (#9703)                                                               

* aeboards/ext65 refactor (#10820)                                                                 

* Refactor xelus/dawn60 for Rev2 later (#10584)                                                    

* add DEBUG_MATRIX_SCAN_RATE_ENABLE to common_features.mk (#10824)                                 

* [Core] Added `add_oneshot_mods` & `del_oneshot_mods` (#10549)                                    

* update chibios os usb for the otg driver (#8893)                                                 

* Remove HD44780 References, Part 4 (#10735)                                                       

* [Keyboard] Add Valor FRL TKL (+refactor) (#10512)                                                

* Fix cursor position bug in oled_write_raw functions (#10800)                                     

* Fixup version.h writing when using SKIP_VERSION=yes (#10972)                                     

* Allow for certain code in the codebase assuming length of string. (#10974)                       

* Add AT90USB support for serial.c (#10706)                                                        

* Auto shift: support repeats and early registration (#9826)                                       

* Rename ledmatrix.h to match .c file (#7949)                                                      

* Split RGB_MATRIX_ENABLE into _ENABLE and _DRIVER (#10231)                                        

* Split LED_MATRIX_ENABLE into _ENABLE and _DRIVER (#10840)                                        

* Merge point for 2020 Nov 28 Breaking Change

* add support for hid gamepad interface
add documentation for HID joystick
Add joystick_task to read analog axes values even when no key is pressed or release. update doc
Update docs/feature_joystick.md
Manage pin setup and read to maintain matrix scan after analog read

* Incorporates patches and changes to HID reporting

There are some patches provided by @a-chol incorporated on this commit,
and also some changes I made to the HID Report structure.

The most interesting is the one dealing with number of buttons: Linux
doesn't seem to care, but Windows requires the HID structure to be byte
aligned (that's in the spec). So if one declares 8/16/32... buttons they
should not have any issues, but this is what happens when you have 9
buttons:

```
 bits |0|1|2|3|4|5|6|7|
      |*|*|*|*|*|*|*|*| axis 0 (report size 8)
      |*|*|*|*|*|*|*|*| ...
      |*|*|*|*|*|*|*|*|
      |*|*|*|*|*|*|*|*|
      |*|*|*|*|*|*|*|*|
      |*|*|*|*|*|*|*|*|
      |*|*|*|*|*|*|*|*| axis 6
      |*|*|*|*|*|*|*|*| first 8 buttons (report size 1)
      |*| | | | | | | | last of 9 buttons, not aligned
```

So for that I added a conditonal that will add a number of reports with
size 1 to make sure it aligns to the next multiple of 8. Those reports
send dummy inputs that don't do anything aside from aligning the data.

Tested on Linux, Windows 10 and Street Fighter (where the joystick is
recognized as direct-input)

* Add save and restore of each pin used in reading joystick (AVR).
Allow output pin to be JS_VIRTUAL_AXIS if the axis is connected to Vcc
instead of an output pin from the MCU.

Fix joystick report id

Fix broken v-usb hid joystick interface. Make it more resilient to unusual settings (none multiple of eight button count, 0 buttons or 0 axes)

Correct adc reading for multiple axes. Piecewise range conversion for uncentered raw value range. Input, output and ground pin configuration per axis.

Documentation fixes

* Fix port addressing for joystick analog read

* The other required set of changes
As per the PR, the changes still holding it up.
Add onekey for testing.
Fix ARM builds.
Fix device descriptor when either axes or buttons is zero.
Add compile-time check for at least one axis or button.
Move definition to try to fix conflict.
PR review comments.
qmk cformat

* avoid float functions to compute range mapping for axis adc reading

* Remove V-USB support for now. Updated docs accordingly.

* Update tmk_core/protocol/lufa/lufa.c

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Update tmk_core/protocol/usb_descriptor.c

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Update tmk_core/protocol/usb_descriptor.c

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Update tmk_core/protocol/usb_descriptor.c

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Add support for joystick adc reading for stm32 MCUs. Fix joystick hid report sending for chibios

* Fix HID joystick report sending for ChibiOS.
Add one analog axis to the onekey:joystick keymap.
Fix pin state save and restore during joystick analog read for STM32
MCUs.

* Update tmk_core/protocol/chibios/usb_main.c

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Update tmk_core/protocol/lufa/lufa.c

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Add missing mcuconf.h and halconf.h to onekey:joystick keymap.
Add suggested fixes from PR.

* Switch saveState and restoreState signature to use pin_t type.
onekey:joystick : add a second axis, virtual and programmatically animated.

* Update docs/feature_joystick.md

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Update docs/feature_joystick.md

Co-Authored-By: Ryan <fauxpark@gmail.com>

* Add PR corrections

* Remove halconf.h and mcuconf.h from onekey keymaps

* Change ADC_PIN to A0

Co-authored-by: achol <allecooll@hotmail.com>
Co-authored-by: José Júnior <jose.junior@gmail.com>
Co-authored-by: a-chol <achol@notamail.com>
Co-authored-by: Nick Brassel <nick@tzarc.org>
Co-authored-by: Ryan <fauxpark@gmail.com>

* Fix incorrect delay when setting WS2812 (and similar) leds

* Add documentation for WS2812_DELAY_MICROSECONDS

* Remove improper cast to uint8_t

Co-authored-by: Sergey Vlasov <sigprof@gmail.com>

* Remove unneeded cast to uint8_t and correct math

Co-authored-by: Sergey Vlasov <sigprof@gmail.com>

* microseconds -> µs

Co-authored-by: Ryan <fauxpark@gmail.com>

* Make documentation better match the spec sheet.

Co-authored-by: Ryan <fauxpark@gmail.com>

* Rename macro to match spec sheet

* Further correction to the delay maths for the SPI case.

Co-authored-by: Joel Challis <git@zvecr.com>

* Move ws2812_common.h to the drivers directory

* Revert "Further correction to the delay maths for the SPI case."

This reverts commit e61b56a2cf.

* Remove ws2812_setleds_pin(); consolidate ws2812.h

Co-authored-by: Sergey Vlasov <sigprof@gmail.com>
Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: Joel Challis <git@zvecr.com>

Co-authored-by: Ryan <fauxpark@gmail.com>

* Change _delay_ms/us() to wait_ms/us()

* Switch to platform-agnostic GPIO macros

* Add AVR spi_master and migrate Adafruit BLE code

* Set verbose back to false

* Add clock divisor, bit order and SPI mode configuration for init

* Add start and stop functions

* Move configuration of mode, endianness and speed to `spi_start()`

* Some breaks here would be good

* Default Adafruit BLE clock divisor to 4 (2MHz on the Feather 32U4)

* Remove mode and divisor enums

* Add some docs

* No hr at EOF

* Add links in sidebar

* Fix AVR ws2812 when ADDRESS_BASE is non zero

* fix port

* remove unused function defs

* Remove pro_micro.h

* Include quantum.h

* Clean up includes for glcdfont headers

* Remove pragma once, most of these are not headers

* Missed these

* Move avr serial code to drivers

* Update src+= serial.c to driver pattern

* Improve support and docs for ADC driver

* Comment ADC channels

* Move to Makers and Modders section, and fix usage instructions

* Flesh out intro

* Superscript 328P note

* Fix pin_to_mux LUT

* Support USB64/1287 as well

* analogReadPin() defaults to 0V mux on invalid pin

* Update pinToMux() function documentation

* Dot

* Accept (some of) the `qmk cformat` changes

* Do clang-format properly

* More wording tweaks

* Link to encoder docs

* Move Ergodox EZ RGB code to custom driver

Also implements full addressing of Ergodox EZ's LED Strip, as written by seebs
Co-authored-by: Seebs <seebs@seebs.net>

* Make Clipping range accessible for custom drivers

* Remove RGBW_BB_TWI from driver and docs

* Revert changes to clipping range support

* Use just rgblight_set instead of full custom driver

* Convert to i2c_master commands

* Rename rgblight driver and clean up includes

* Fix unicode in comments

Co-Authored-By: fauxpark <fauxpark@gmail.com>

* Remove separate RGBW implementation for a unified function

* Set White to 0 in RGBW LEDs

This is just to get this working, later, proper brightness can be handled elsewhere.

* Use us instead of nanoseconds(?) since it renders correctly on web

* Remove RGBW function from arm/ws2812.h

* Remove RGBW function from arm/ws2812.c

* Formatting changes

* Add doc info

* Refactor ps2avrgb i2c ws2812 to core

* Refactor jj40 to use ws2812 i2c driver

* Refactor ps2avrgb template to use ws2812 i2c driver

* Add ws2812 stub files

* clang-format and driver config

* Add ws2812 driver docs

* Fix default config values

* Update tmk_core/protocol/vusb/main.c

Co-Authored-By: Drashna Jaelre <drashna@live.com>

* Reduce duplication for ARM/AVR ws2812 rgb_matrix driver

* Reduce duplication for ARM/AVR ws2812 rgb_matrix driver - Fix setled_all use of r,g,b

* Fix battery level code in adafruit_ble.cpp

The code in tsk_core/protocol/lufa/adafluit_ble.cpp that polls the
battery level for the Adafruit feather BLE controller reads the
regulated voltage, not the raw voltage coming from the battery. To do
that, the Adafruit Feather docs say you should read from pin A9:
https://learn.adafruit.com/adafruit-feather-32u4-basic-proto/power-management#measuring-battery-4-9.
(See also
https://learn.adafruit.com/adafruit-feather-32u4-bluefruit-le/pinouts#logic-pins-2-9.)

I'm not sure why, but analogRead(9); doesn't read the correct pin.
Checking all available analog pins experimentally, it turns out that
analogRead(7); returns the correct value. So the code above should read:

    state.vbat = analogRead(7);

* Update tmk_core/protocol/lufa/adafruit_ble.cpp

Co-Authored-By: Drashna Jaelre <drashna@live.com>

* Remove old comment

* Fix linking error

* Remove `#ifdef` around `#include analog.h`.

* Really fix linking error

* Add GPL3 header to avr i2c files

* Add for i2c_slave as well

* Fix formatting of license header

Because someone named the define poorly

Using full relative path as handwired/promethium has a color.h file

* WS2812 driver implementation for RGB Matrix

* Added driver configuration docs

* On i2c_init, enable two wire interface, twi interrupt, and slave
address ACK along with pull up resistors.

* thanks to some testing by drashna, we know that setting TWI doesn't work for all boards. Putting the new code into an ifdef block

* Update split_common to use standard i2c drivers

* Eliminate RGB_DIRTY/BACKLIT_DIRTY

* Fix avr i2c_master error handling

* Fix i2c_slave addressing

* Remove unneeded timeout on i2c_stop()

* Fix RGB I2C transfers

* Remove incorrect comment

* Fixed pin for RGB

* Re-did apa102 stuff

* changed to use pincontrol functions

* Removed a newline?

* Changed to comply with project style

* Update Practice60 to enable RGB via SPI DMA and use PWM backlight breathing

* Correct stm32f103c8t6 flash size in eeprom definition

* Remove unused files and improve ifdef checks

* Update quantum/rgblight.c

Co-Authored-By: awkannan <andrew.kannan@klaviyo.com>

* Update quantum/rgblight.c

Co-Authored-By: awkannan <andrew.kannan@klaviyo.com>

* EEPROM implementation fix and updated p60 code

* Update define

* Remove dead code

* Update keymap to remove test key

* Update keymap again

Also merges tx/rx buffers, as only one is necessary.

* add touchpad

* progress

* working with leds and vibrations

* adds readme

* Update keyboards/touchpad/readme.md

Co-Authored-By: jackhumbert <jack.humb@gmail.com>

* updates

Fixes #3641

* DC01 updates and I2C avr speed overwrite

- General updating of DC01
- Made F_SCL define in AVR I2C driver overwritable from config.h

* Update drivers/avr/i2c_master.c

* Addition of I2C master driver for STM32, Generalization of ISSI3731 driver

- Addition of an i2c_master driver for STM32 to replicate expectations of AVR driver.
- Moved ISSI3731 driver one level up to make it accesible by both architectures.
- Renamed ISSI3731 functions to a more general name for preparation of other ISSI drivers.
- Added compiler directives where necessary to differenciate each architecture.

* converted tabs to spaces

* DC01 initial commit

- Addition of directories
- Left readme

* Initial commit of left half

* Initial files for right half

* arrow

* i2c adjustments

* I2C slave and DC01 refractoring

- Cleaned up state machine of I2C slave driver
- Modified DC01 left to use already pressent I2C master driver
- Modified DC01 matrixes

* Fixed tabs to spaces

* Addition of Numpad

* Add keymaps

- Orthopad keymap for numpad module
- Numpad keymap for numpad module
- ISO, ANSI and HHKB version of keymap for right module

* Minor matrix.c fixes

* Update Readmes

* integrated Peter Fleury's LCD library for HD44780 LCDs

* fixed typo

* cleanup finished

* add documentation

* added HD44780 documentation

* removed keyboard from .gitmodules

* resolved merge conflict

* removed edit of kira75s rules.mk made by merge

* moved hd44780 to drivers/avr

* Added licence info to hd44780 files

* Added link to hd44780 docs.

- Add I2C slave library for general use.