[Core] Fix "6kro enable" and clarify naming (#14563)

* Fix USB_6KRO_ENABLE compilation errors

* Add info to docs

* Rename define to be more accurate

* Remove unused rule

* Refixe docs

11 files changed, 24 insertions, 30 deletions

diff --git a/docs/config_options.md b/docs/config_options.md
index 7584d3584..dbf3d3da2 100644
--- a/docs/config_options.md
+++ b/docs/config_options.md
@@ -418,6 +418,8 @@ Use these to enable or disable building certain features. The more you have enab
   * Key combo feature
 * `NKRO_ENABLE`
   * USB N-Key Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
+* `RING_BUFFERED_6KRO_REPORT_ENABLE`
+  * USB 6-Key Rollover - Instead of stopping any new input once 6 keys are pressed, the oldest key is released and the new key is pressed. 
 * `AUDIO_ENABLE`
   * Enable the audio subsystem.
 * `KEY_OVERRIDE_ENABLE`
diff --git a/keyboards/hotdox/rules.mk b/keyboards/hotdox/rules.mk
index 3802dbe99..6caa17fab 100644
--- a/keyboards/hotdox/rules.mk
+++ b/keyboards/hotdox/rules.mk
@@ -16,7 +16,6 @@ CONSOLE_ENABLE          = yes # Console for debug
 COMMAND_ENABLE          = no  # Commands for debug and configuration
 SLEEP_LED_ENABLE        = no  # Breathing sleep LED during USB suspend
 NKRO_ENABLE             = yes # USB Nkey Rollover - not yet supported in LUFA
-USB_6KRO_ENABLE         = no  # USB 6key Rollover
 BACKLIGHT_ENABLE        = yes # Enable keyboard backlight functionality
 SWAP_HANDS_ENABLE       = no  # Disable Onehand
 RGBLIGHT_ENABLE         = no
diff --git a/keyboards/ktec/ergodone/rules.mk b/keyboards/ktec/ergodone/rules.mk
index 3c1723a3c..f0478eb3a 100644
--- a/keyboards/ktec/ergodone/rules.mk
+++ b/keyboards/ktec/ergodone/rules.mk
@@ -16,7 +16,6 @@ CONSOLE_ENABLE          = no  # Console for debug
 COMMAND_ENABLE          = no  # Commands for debug and configuration
 SLEEP_LED_ENABLE        = no  # Breathing sleep LED during USB suspend
 NKRO_ENABLE             = yes # USB Nkey Rollover - not yet supported in LUFA
-USB_6KRO_ENABLE         = no  # USB 6key Rollover
 BACKLIGHT_ENABLE        = no  # Enable keyboard backlight functionality
 SWAP_HANDS_ENABLE       = no  # Disable Onehand
 RGBLIGHT_ENABLE         = no
diff --git a/keyboards/planck/keymaps/not-quite-neo/rules.mk b/keyboards/planck/keymaps/not-quite-neo/rules.mk
index b30c3a21e..b4e2e5c81 100644
--- a/keyboards/planck/keymaps/not-quite-neo/rules.mk
+++ b/keyboards/planck/keymaps/not-quite-neo/rules.mk
@@ -12,7 +12,6 @@ EXTRAKEY_ENABLE     = yes    # Audio control and System control(+450)
 CONSOLE_ENABLE      = no    # Console for debug(+400)
 COMMAND_ENABLE      = no    # Commands for debug and configuration
 NKRO_ENABLE         = yes   # Nkey Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
-USB_6KRO_ENABLE     = no    # 6key Rollover
 BACKLIGHT_ENABLE    = no    # Enable keyboard backlight functionality
 MIDI_ENABLE         = no    # MIDI controls
 AUDIO_ENABLE        = no    # Audio output on port C6
@@ -20,7 +19,6 @@ AUDIO_ENABLE        = no    # Audio output on port C6
 UNICODE_ENABLE      = no    # Unicode (can't be used with unicodemap)
 UNICODEMAP_ENABLE   = no   # Enable extended unicode
 BLUETOOTH_ENABLE    = no    # Enable Bluetooth with the Adafruit EZ-Key HID
-RGBLIGHT_ENABLE     = no    # Enable WS2812 RGB underlight. 
+RGBLIGHT_ENABLE     = no    # Enable WS2812 RGB underlight.
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE    = no    # Breathing sleep LED during USB suspend
-
diff --git a/keyboards/planck/keymaps/zach/rules.mk b/keyboards/planck/keymaps/zach/rules.mk
index 3247aece2..544e10a45 100644
--- a/keyboards/planck/keymaps/zach/rules.mk
+++ b/keyboards/planck/keymaps/zach/rules.mk
@@ -2,7 +2,7 @@
 # Max .hex size is about 28636 bytes
 
 # Build Options
-#   change to "no" to disable the options, or define them in the Makefile in 
+#   change to "no" to disable the options, or define them in the Makefile in
 #   the appropriate keymap folder that will get included automatically
 #
 TAP_DANCE_ENABLE    = yes   # Enable TapDance functionality
@@ -12,7 +12,6 @@ EXTRAKEY_ENABLE     = no    # Audio control and System control(+450)
 CONSOLE_ENABLE      = no    # Console for debug(+400)
 COMMAND_ENABLE      = no    # Commands for debug and configuration
 NKRO_ENABLE         = yes   # Nkey Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
-USB_6KRO_ENABLE     = no    # 6key Rollover
 BACKLIGHT_ENABLE    = no    # Enable keyboard backlight functionality
 MIDI_ENABLE         = no    # MIDI controls
 AUDIO_ENABLE        = no    # Audio output on port C6
@@ -20,7 +19,6 @@ AUDIO_ENABLE        = no    # Audio output on port C6
 UNICODE_ENABLE      = no    # Unicode (can't be used with unicodemap)
 UNICODEMAP_ENABLE   = yes   # Enable extended unicode
 BLUETOOTH_ENABLE    = no    # Enable Bluetooth with the Adafruit EZ-Key HID
-RGBLIGHT_ENABLE     = no    # Enable WS2812 RGB underlight. 
+RGBLIGHT_ENABLE     = no    # Enable WS2812 RGB underlight.
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE    = no    # Breathing sleep LED during USB suspend
-
diff --git a/keyboards/preonic/keymaps/zach/rules.mk b/keyboards/preonic/keymaps/zach/rules.mk
index 8d2f75eea..8cd4f98ee 100644
--- a/keyboards/preonic/keymaps/zach/rules.mk
+++ b/keyboards/preonic/keymaps/zach/rules.mk
@@ -2,7 +2,7 @@
 # Max .hex size is about 28636 bytes
 
 # Build Options
-#   change to "no" to disable the options, or define them in the Makefile in 
+#   change to "no" to disable the options, or define them in the Makefile in
 #   the appropriate keymap folder that will get included automatically
 #
 TAP_DANCE_ENABLE    = yes   # Enable TapDance functionality
@@ -12,7 +12,6 @@ EXTRAKEY_ENABLE     = no    # Audio control and System control(+450)
 CONSOLE_ENABLE      = no    # Console for debug(+400)
 COMMAND_ENABLE      = no    # Commands for debug and configuration
 NKRO_ENABLE         = yes   # Nkey Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
-USB_6KRO_ENABLE     = no    # 6key Rollover
 BACKLIGHT_ENABLE    = yes   # Enable keyboard backlight functionality
 MIDI_ENABLE         = no    # MIDI controls
 AUDIO_ENABLE        = yes   # Audio output on port C6
@@ -20,7 +19,6 @@ AUDIO_ENABLE        = yes   # Audio output on port C6
 UNICODE_ENABLE      = no    # Unicode
 UNICODEMAP_ENABLE   = yes   # Enable extended unicode
 BLUETOOTH_ENABLE    = no    # Enable Bluetooth with the Adafruit EZ-Key HID
-RGBLIGHT_ENABLE     = no    # Enable WS2812 RGB underlight. 
+RGBLIGHT_ENABLE     = no    # Enable WS2812 RGB underlight.
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE    = no    # Breathing sleep LED during USB suspend
-
diff --git a/quantum/action_util.c b/quantum/action_util.c
index 2b3c00cba..9a85bd504 100644
--- a/quantum/action_util.c
+++ b/quantum/action_util.c
@@ -32,16 +32,6 @@ static uint8_t weak_override_mods = 0;
 static uint8_t suppressed_mods    = 0;
 #endif
 
-#ifdef USB_6KRO_ENABLE
-#    define RO_ADD(a, b) ((a + b) % KEYBOARD_REPORT_KEYS)
-#    define RO_SUB(a, b) ((a - b + KEYBOARD_REPORT_KEYS) % KEYBOARD_REPORT_KEYS)
-#    define RO_INC(a) RO_ADD(a, 1)
-#    define RO_DEC(a) RO_SUB(a, 1)
-static int8_t cb_head  = 0;
-static int8_t cb_tail  = 0;
-static int8_t cb_count = 0;
-#endif
-
 // TODO: pointer variable is not needed
 // report_keyboard_t keyboard_report = {};
 report_keyboard_t *keyboard_report = &(report_keyboard_t){};
diff --git a/show_options.mk b/show_options.mk
index ce2f9c063..b17d8c7d9 100644
--- a/show_options.mk
+++ b/show_options.mk
@@ -72,7 +72,7 @@ OTHER_OPTION_NAMES = \
   PS2_MOUSE_ENABLE \
   RAW_ENABLE \
   SWAP_HANDS_ENABLE \
-  USB_6KRO_ENABLE \
+  RING_BUFFERED_6KRO_REPORT_ENABLE \
   WATCHDOG_ENABLE \
   XT_ENABLE \
   ERGOINU \
diff --git a/tests/test_common/keyboard_report_util.cpp b/tests/test_common/keyboard_report_util.cpp
index cb044c92b..f73cf239e 100644
--- a/tests/test_common/keyboard_report_util.cpp
+++ b/tests/test_common/keyboard_report_util.cpp
@@ -24,7 +24,7 @@ std::vector<uint8_t> get_keys(const report_keyboard_t& report) {
     std::vector<uint8_t> result;
 #if defined(NKRO_ENABLE)
 #    error NKRO support not implemented yet
-#elif defined(USB_6KRO_ENABLE)
+#elif defined(RING_BUFFERED_6KRO_REPORT_ENABLE)
 #    error 6KRO support not implemented yet
 #else
     for (size_t i = 0; i < KEYBOARD_REPORT_KEYS; i++) {
diff --git a/tmk_core/common.mk b/tmk_core/common.mk
index 7f7420059..e44ff2f0a 100644
--- a/tmk_core/common.mk
+++ b/tmk_core/common.mk
@@ -63,8 +63,8 @@ ifeq ($(strip $(NKRO_ENABLE)), yes)
     endif
 endif
 
-ifeq ($(strip $(USB_6KRO_ENABLE)), yes)
-    TMK_COMMON_DEFS += -DUSB_6KRO_ENABLE
+ifeq ($(strip $(RING_BUFFERED_6KRO_REPORT_ENABLE)), yes)
+    TMK_COMMON_DEFS += -DRING_BUFFERED_6KRO_REPORT_ENABLE
 endif
 
 ifeq ($(strip $(SLEEP_LED_ENABLE)), yes)
diff --git a/tmk_core/common/report.c b/tmk_core/common/report.c
index 1bcb6f2ad..2a7fc006c 100644
--- a/tmk_core/common/report.c
+++ b/tmk_core/common/report.c
@@ -21,6 +21,16 @@
 #include "util.h"
 #include <string.h>
 
+#ifdef RING_BUFFERED_6KRO_REPORT_ENABLE
+#    define RO_ADD(a, b) ((a + b) % KEYBOARD_REPORT_KEYS)
+#    define RO_SUB(a, b) ((a - b + KEYBOARD_REPORT_KEYS) % KEYBOARD_REPORT_KEYS)
+#    define RO_INC(a)    RO_ADD(a, 1)
+#    define RO_DEC(a)    RO_SUB(a, 1)
+static int8_t cb_head  = 0;
+static int8_t cb_tail  = 0;
+static int8_t cb_count = 0;
+#endif
+
 /** \brief has_anykey
  *
  * FIXME: Needs doc
@@ -54,7 +64,7 @@ uint8_t get_first_key(report_keyboard_t* keyboard_report) {
         return i << 3 | biton(keyboard_report->nkro.bits[i]);
     }
 #endif
-#ifdef USB_6KRO_ENABLE
+#ifdef RING_BUFFERED_6KRO_REPORT_ENABLE
     uint8_t i = cb_head;
     do {
         if (keyboard_report->keys[i] != 0) {
@@ -99,7 +109,7 @@ bool is_key_pressed(report_keyboard_t* keyboard_report, uint8_t key) {
  * FIXME: Needs doc
  */
 void add_key_byte(report_keyboard_t* keyboard_report, uint8_t code) {
-#ifdef USB_6KRO_ENABLE
+#ifdef RING_BUFFERED_6KRO_REPORT_ENABLE
     int8_t i     = cb_head;
     int8_t empty = -1;
     if (cb_count) {
@@ -166,7 +176,7 @@ void add_key_byte(report_keyboard_t* keyboard_report, uint8_t code) {
  * FIXME: Needs doc
  */
 void del_key_byte(report_keyboard_t* keyboard_report, uint8_t code) {
-#ifdef USB_6KRO_ENABLE
+#ifdef RING_BUFFERED_6KRO_REPORT_ENABLE
     uint8_t i = cb_head;
     if (cb_count) {
         do {