feat(ble): automatically turn off BLE indicator

doing so will balance power usage for the left and right parts,
as previously the BLE indicator stays on for the left half all the time.

app/Kconfig

@@ -172,6 +172,10 @@ config ZMK_HANDLE_BLE_DISCONNECTION
     bool "Experimental: Respect user disconnection request from computer"
     default n
 
+config ZMK_BLE_INDICATOR_AUTO_OFF
+    bool "Experimental: automatically turn off BLE indicator"
+    default n
+
 config BT_PERIPHERAL_PREF_MIN_INT
     default 6
 

app/include/zmk/ble.h

@@ -38,3 +38,7 @@ int zmk_ble_unpair_all();
 bt_addr_le_t *zmk_ble_get_peripheral_addr();
 int zmk_ble_put_peripheral_addr(const bt_addr_le_t *addr);
 #endif /* IS_ENABLED(CONFIG_ZMK_SPLIT_ROLE_CENTRAL) */
+
+#if IS_ENABLED(CONFIG_ZMK_HANDLE_BLE_DISCONNECTION)
+bool ble_seeking_connection();
+#endif

app/src/ble.c

@@ -106,6 +106,10 @@ bool zmk_ble_active_profile_is_open() {
     return !bt_addr_le_cmp(&profiles[active_profile].peer, BT_ADDR_LE_ANY);
 }
 
+#if IS_ENABLED(CONFIG_ZMK_HANDLE_BLE_DISCONNECTION)
+bool ble_seeking_connection() { return active_profile_seeking_connection; }
+#endif
+
 void set_profile_address(uint8_t index, const bt_addr_le_t *addr) {
     char setting_name[15];
     char addr_str[BT_ADDR_LE_STR_LEN];

app/src/rgb_underglow.c

@@ -84,8 +84,14 @@ static struct rgb_underglow_state state;
 static struct zmk_periph_led led_data;
 
 #if IS_ENABLED(CONFIG_ZMK_SPLIT_BLE)
-static bool last_ble_state[2];
-#endif
+
+static bool last_ble_state[3];
+
+#if IS_ENABLED(CONFIG_ZMK_BLE_INDICATOR_AUTO_OFF)
+bool reset_auto_off_counter = true;
+#endif /* CONFIG_ZMK_BLE_INDICATOR_AUTO_OFF */
+
+#endif /* CONFIG_ZMK_SPLIT_BLE */
 
 static bool triggered;
 
@@ -261,6 +267,9 @@ static void zmk_rgb_underglow_effect_kinesis() {
     }
     // blink second led slowly if bluetooth not paired, quickly if not connected
     if (zmk_ble_active_profile_is_open()) {
+#if IS_ENABLED(CONFIG_ZMK_BLE_INDICATOR_AUTO_OFF)
+        reset_auto_off_counter = true;
+#endif
         pixels[1].r = pixels[1].r * last_ble_state[0];
         pixels[1].g = pixels[1].g * last_ble_state[0];
         pixels[1].b = pixels[1].b * last_ble_state[0];
@@ -270,6 +279,27 @@ static void zmk_rgb_underglow_effect_kinesis() {
         }
         state.animation_step++;
     } else if (!zmk_ble_active_profile_is_connected()) {
+#if IS_ENABLED(CONFIG_ZMK_BLE_INDICATOR_AUTO_OFF)
+        reset_auto_off_counter = true;
+#endif
+
+#if IS_ENABLED(CONFIG_ZMK_HANDLE_BLE_DISCONNECTION)
+        /* only blink the led when BLE is advertising for connection */
+        if (ble_seeking_connection()) {
+            pixels[1].r = pixels[1].r * last_ble_state[1];
+            pixels[1].g = pixels[1].g * last_ble_state[1];
+            pixels[1].b = pixels[1].b * last_ble_state[1];
+            if (state.animation_step > 14) {
+                last_ble_state[1] = !last_ble_state[1];
+                state.animation_step = 0;
+            }
+            state.animation_step++;
+        } else {
+            pixels[1].r = 0;
+            pixels[1].g = 0;
+            pixels[1].b = 0;
+        }
+#else  /* IS_ENABLED(CONFIG_ZMK_HANDLE_BLE_DISCONNECTION) */
         pixels[1].r = pixels[1].r * last_ble_state[1];
         pixels[1].g = pixels[1].g * last_ble_state[1];
         pixels[1].b = pixels[1].b * last_ble_state[1];
@@ -278,7 +308,29 @@ static void zmk_rgb_underglow_effect_kinesis() {
             state.animation_step = 0;
         }
         state.animation_step++;
+#endif /* IS_ENABLED(CONFIG_ZMK_HANDLE_BLE_DISCONNECTION) */
     }
+#if IS_ENABLED(CONFIG_ZMK_BLE_INDICATOR_AUTO_OFF)
+    else {                         // ble is connected
+        if (led_data.layer == 3) { // when mod key is pressed,
+                                   // show current BLE profile for few seconds and then off
+            reset_auto_off_counter = true;
+        }
+        if (reset_auto_off_counter) {
+            state.animation_step = 0;
+            last_ble_state[2] = true;
+            reset_auto_off_counter = false;
+        }
+        pixels[1].r = pixels[1].r * last_ble_state[2];
+        pixels[1].g = pixels[1].g * last_ble_state[2];
+        pixels[1].b = pixels[1].b * last_ble_state[2];
+        if (state.animation_step > 84) {
+            last_ble_state[2] = false;
+        } else {
+            state.animation_step++;
+        }
+    }
+#endif /* IS_ENABLED(CONFIG_ZMK_HANDLE_BLE_DISCONNECTION) */
     // set third led as layer state
     switch (led_data.layer) {
     case 0:
@@ -330,7 +382,7 @@ static void zmk_rgb_underglow_effect_kinesis() {
     if (old_led_data.layer != led_data.layer || old_led_data.indicators != led_data.indicators) {
         zmk_rgb_underglow_central_send();
     }
-#else
+#else /* ZMK_BLE_IS_CENTRAL */
 #if IS_ENABLED(CONFIG_ZMK_SPLIT_BLE)
     // leds for peripheral(right) side
     /* if (zmk_ble_active_profile_is_open()) {
@@ -431,7 +483,7 @@ static void zmk_rgb_underglow_effect_kinesis() {
 #if IS_ENABLED(CONFIG_ZMK_SPLIT_BLE)
     }
 #endif
-#endif
+#endif /* ZMK_BLE_IS_CENTRAL */
 }
 
 static void zmk_rgb_underglow_effect_test() {

docs/docs/config/system.md

@@ -78,8 +78,12 @@ for more information on configuring Bluetooth.
 | `CONFIG_ZMK_BLE_THREAD_STACK_SIZE`          | int  | Stack size of the BLE notify thread                                   | 512     |
 | `CONFIG_ZMK_BLE_PASSKEY_ENTRY`              | bool | Experimental: require typing passkey from host to pair BLE connection | n       |
 | `CONFIG_ZMK_HANDLE_BLE_DISCONNECTION`       | bool | Experimental: respect user BLE disconnection request from computer    | n       |
+| `CONFIG_ZMK_BLE_INDICATOR_AUTO_OFF`         | bool | Experimental (Adv360): only show BLE profile indicator when triggered | n       |
 
-Note that `CONFIG_BT_MAX_CONN` and `CONFIG_BT_MAX_PAIRED` should be set to the same value. On a split keyboard they should only be set for the central and must be set to one greater than the desired number of bluetooth profiles.
+Note:
+
+1. `CONFIG_BT_MAX_CONN` and `CONFIG_BT_MAX_PAIRED` should be set to the same value. On a split keyboard they should only be set for the central and must be set to one greater than the desired number of bluetooth profiles.
+2. When `CONFIG_ZMK_BLE_INDICATOR_AUTO_OFF=y`, the BLE indicator will automatically turn off when there is no Bluetooth related activity. It will also be triggered to show the current BLE profile number when the 'Mod' key is pressed on the Adv360.
 
 ### Logging