refactor(behaviors): Add max-held tap-dance config (#2838)

refactor(behaviors): Add max-held tap-dance config

Add new `CONFIG_ZMK_BEHAVIOR_TAP_DANCE_MAX_HELD` config for reducing RAM
usage on more constrained devices.

refactor(behaviors): Move defaults to Kconfig.defaults

app/CMakeLists.txt

@@ -67,7 +67,7 @@ if ((NOT CONFIG_ZMK_SPLIT) OR CONFIG_ZMK_SPLIT_ROLE_CENTRAL)
   target_sources_ifdef(CONFIG_ZMK_BEHAVIOR_STUDIO_UNLOCK app PRIVATE src/behaviors/behavior_studio_unlock.c)
   target_sources_ifdef(CONFIG_ZMK_BEHAVIOR_INPUT_TWO_AXIS app PRIVATE src/behaviors/behavior_input_two_axis.c)
   target_sources(app PRIVATE src/combo.c)
-  target_sources(app PRIVATE src/behaviors/behavior_tap_dance.c)
+  target_sources_ifdef(CONFIG_ZMK_BEHAVIOR_TAP_DANCE app PRIVATE src/behaviors/behavior_tap_dance.c)
   target_sources(app PRIVATE src/behavior_queue.c)
   target_sources(app PRIVATE src/conditional_layer.c)
   target_sources(app PRIVATE src/endpoints.c)

app/Kconfig.behaviors

@@ -51,13 +51,11 @@ if ZMK_BEHAVIOR_HOLD_TAP
 
 config ZMK_BEHAVIOR_HOLD_TAP_MAX_HELD
     int "Hold Tap Max Held"
-    default 10
     help
       Max number of simultaneously held hold-taps
 
 config ZMK_BEHAVIOR_HOLD_TAP_MAX_CAPTURED_EVENTS
     int "Hold Tap Max Captured Events"
-    default 40
     help
       Max number of captured system events while waiting to resolve hold taps
 
@@ -82,7 +80,6 @@ if ZMK_BEHAVIOR_STICKY_KEY
 
 config ZMK_BEHAVIOR_STICKY_KEY_MAX_HELD
     int "Sticky Key Max Held"
-    default 10
     help
       Max number of simultaneously held sticky keys
 
@@ -93,6 +90,21 @@ config ZMK_BEHAVIOR_SOFT_OFF
     default y
     depends on DT_HAS_ZMK_BEHAVIOR_SOFT_OFF_ENABLED && ZMK_PM_SOFT_OFF
 
+
+config ZMK_BEHAVIOR_TAP_DANCE
+    bool
+    default y
+    depends on DT_HAS_ZMK_BEHAVIOR_TAP_DANCE_ENABLED
+
+if ZMK_BEHAVIOR_TAP_DANCE
+
+config ZMK_BEHAVIOR_TAP_DANCE_MAX_HELD
+    int "Tap-Dance Max Held"
+    help
+      Max number of simultaneously held taps-dances
+
+endif
+
 config ZMK_BEHAVIOR_INPUT_TWO_AXIS
     bool
     default y

app/Kconfig.defaults

@@ -12,6 +12,32 @@ endif
 config ZMK_HID_CONSUMER_REPORT_SIZE
     default 6
 
+# Behaviors
+
+if ZMK_BEHAVIOR_HOLD_TAP
+
+config ZMK_BEHAVIOR_HOLD_TAP_MAX_HELD
+    default 10
+
+config ZMK_BEHAVIOR_HOLD_TAP_MAX_CAPTURED_EVENTS
+    default 40
+
+endif
+
+if ZMK_BEHAVIOR_STICKY_KEY
+
+config ZMK_BEHAVIOR_STICKY_KEY_MAX_HELD
+    default 10
+
+endif
+
+if ZMK_BEHAVIOR_TAP_DANCE
+
+config ZMK_BEHAVIOR_TAP_DANCE_MAX_HELD
+    default 10
+
+endif
+
 # Underglow
 if ZMK_RGB_UNDERGLOW
 

app/src/behaviors/behavior_tap_dance.c

@@ -21,7 +21,7 @@ LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
 
 #if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)
 
-#define ZMK_BHV_TAP_DANCE_MAX_HELD 10
+#define ZMK_BHV_TAP_DANCE_MAX_HELD CONFIG_ZMK_BEHAVIOR_TAP_DANCE_MAX_HELD
 
 #define ZMK_BHV_TAP_DANCE_POSITION_FREE UINT32_MAX
 

docs/docs/config/behaviors.md

@@ -325,6 +325,12 @@ Creates a custom behavior that triggers a different behavior corresponding to th
 
 See the [tap dance behavior](../keymaps/behaviors/tap-dance.mdx) documentation for more details and examples.
 
+### Kconfig
+
+| Config                                   | Type | Description                                    | Default |
+| ---------------------------------------- | ---- | ---------------------------------------------- | ------- |
+| `CONFIG_ZMK_BEHAVIOR_TAP_DANCE_MAX_HELD` | int  | Maximum number of simultaneous held tap-dances | 10      |
+
 ### Devicetree
 
 Definition file: [zmk/app/dts/bindings/behaviors/zmk,behavior-tap-dance.yaml](https://github.com/zmkfirmware/zmk/blob/main/app/dts/bindings/behaviors/zmk%2Cbehavior-tap-dance.yaml)