Bind Bluetooth driver to `host_driver_t` (#25199)

builddefs/common_features.mk

···
     NO_USB_STARTUP_CHECK := yes
     CONNECTION_ENABLE := yes
     COMMON_VPATH += $(DRIVER_PATH)/bluetooth
+    SRC += $(DRIVER_PATH)/bluetooth/bluetooth.c
 
     ifeq ($(strip $(BLUETOOTH_DRIVER)), bluefruit_le)
         SPI_DRIVER_REQUIRED = yes
-        SRC += $(DRIVER_PATH)/bluetooth/bluetooth.c
+        SRC += $(DRIVER_PATH)/bluetooth/bluetooth_drivers.c
         SRC += $(DRIVER_PATH)/bluetooth/bluefruit_le.cpp
     endif
 
     ifeq ($(strip $(BLUETOOTH_DRIVER)), rn42)
         UART_DRIVER_REQUIRED = yes
-        SRC += $(DRIVER_PATH)/bluetooth/bluetooth.c
+        SRC += $(DRIVER_PATH)/bluetooth/bluetooth_drivers.c
         SRC += $(DRIVER_PATH)/bluetooth/rn42.c
     endif
 endif

drivers/bluetooth/bluetooth.c

···
-/*
- * Copyright 2022
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
+// Copyright 2025 QMK
+// SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "bluetooth.h"
 
-#if defined(BLUETOOTH_BLUEFRUIT_LE)
-#    include "bluefruit_le.h"
-#elif defined(BLUETOOTH_RN42)
-#    include "rn42.h"
-#endif
+__attribute__((weak)) void bluetooth_init(void) {}
 
-void bluetooth_init(void) {
-#if defined(BLUETOOTH_BLUEFRUIT_LE)
-    bluefruit_le_init();
-#elif defined(BLUETOOTH_RN42)
-    rn42_init();
-#endif
-}
+__attribute__((weak)) void bluetooth_task(void) {}
 
-void bluetooth_task(void) {
-#if defined(BLUETOOTH_BLUEFRUIT_LE)
-    bluefruit_le_task();
-#endif
+__attribute__((weak)) bool bluetooth_is_connected(void) {
+    return true;
 }
 
-void bluetooth_send_keyboard(report_keyboard_t *report) {
-#if defined(BLUETOOTH_BLUEFRUIT_LE)
-    bluefruit_le_send_keyboard(report);
-#elif defined(BLUETOOTH_RN42)
-    rn42_send_keyboard(report);
-#endif
+__attribute__((weak)) uint8_t bluetooth_keyboard_leds(void) {
+    return 0;
 }
 
-void bluetooth_send_mouse(report_mouse_t *report) {
-#if defined(BLUETOOTH_BLUEFRUIT_LE)
-    bluefruit_le_send_mouse(report);
-#elif defined(BLUETOOTH_RN42)
-    rn42_send_mouse(report);
-#endif
-}
+__attribute__((weak)) void bluetooth_send_keyboard(report_keyboard_t *report) {}
+
+__attribute__((weak)) void bluetooth_send_nkro(report_nkro_t *report) {}
+
+__attribute__((weak)) void bluetooth_send_mouse(report_mouse_t *report) {}
+
+__attribute__((weak)) void bluetooth_send_consumer(uint16_t usage) {}
 
-void bluetooth_send_consumer(uint16_t usage) {
-#if defined(BLUETOOTH_BLUEFRUIT_LE)
-    bluefruit_le_send_consumer(usage);
-#elif defined(BLUETOOTH_RN42)
-    rn42_send_consumer(usage);
-#endif
-}
+__attribute__((weak)) void bluetooth_send_system(uint16_t usage) {}

drivers/bluetooth/bluetooth.h

···
 void bluetooth_task(void);
 
 /**
+ * \brief Detects if Bluetooth is connected.
+ *
+ * \return `true` if connected, `false` otherwise.
+ */
+bool bluetooth_is_connected(void);
+
+/**
+ * \brief Get current LED state.
+ */
+uint8_t bluetooth_keyboard_leds(void);
+
+/**
  * \brief Send a keyboard report.
  *
  * \param report The keyboard report to send.
···
 void bluetooth_send_keyboard(report_keyboard_t *report);
 
 /**
+ * \brief Send a nkro report.
+ *
+ * \param report The nkro report to send.
+ */
+void bluetooth_send_nkro(report_nkro_t *report);
+
+/**
  * \brief Send a mouse report.
  *
  * \param report The mouse report to send.
···
  * \param usage The consumer usage to send.
  */
 void bluetooth_send_consumer(uint16_t usage);
+
+/**
+ * \brief Send a system usage.
+ *
+ * \param usage The system usage to send.
+ */
+void bluetooth_send_system(uint16_t usage);

drivers/bluetooth/bluetooth_drivers.c

···
+/*
+ * Copyright 2022
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "bluetooth.h"
+
+#if defined(BLUETOOTH_BLUEFRUIT_LE)
+#    include "bluefruit_le.h"
+#elif defined(BLUETOOTH_RN42)
+#    include "rn42.h"
+#endif
+
+void bluetooth_init(void) {
+#if defined(BLUETOOTH_BLUEFRUIT_LE)
+    bluefruit_le_init();
+#elif defined(BLUETOOTH_RN42)
+    rn42_init();
+#endif
+}
+
+void bluetooth_task(void) {
+#if defined(BLUETOOTH_BLUEFRUIT_LE)
+    bluefruit_le_task();
+#endif
+}
+
+bool bluetooth_is_connected(void) {
+#if defined(BLUETOOTH_BLUEFRUIT_LE)
+    return bluefruit_le_is_connected();
+#else
+    // TODO: drivers should check if BT is connected here
+    return true;
+#endif
+}
+
+void bluetooth_send_keyboard(report_keyboard_t *report) {
+#if defined(BLUETOOTH_BLUEFRUIT_LE)
+    bluefruit_le_send_keyboard(report);
+#elif defined(BLUETOOTH_RN42)
+    rn42_send_keyboard(report);
+#endif
+}
+
+void bluetooth_send_mouse(report_mouse_t *report) {
+#if defined(BLUETOOTH_BLUEFRUIT_LE)
+    bluefruit_le_send_mouse(report);
+#elif defined(BLUETOOTH_RN42)
+    rn42_send_mouse(report);
+#endif
+}
+
+void bluetooth_send_consumer(uint16_t usage) {
+#if defined(BLUETOOTH_BLUEFRUIT_LE)
+    bluefruit_le_send_consumer(usage);
+#elif defined(BLUETOOTH_RN42)
+    rn42_send_consumer(usage);
+#endif
+}

quantum/connection/connection.c

···
 #include "usb_util.h"
 #include "util.h"
 
+#ifdef BLUETOOTH_ENABLE
+#    include "bluetooth.h"
+#endif
+
 // ======== DEPRECATED DEFINES - DO NOT USE ========
 #ifdef OUTPUT_DEFAULT
 #    undef CONNECTION_HOST_DEFAULT
···
 
 __attribute__((weak)) void set_output_user(uint8_t output) {}
 // ========
-
-#ifdef BLUETOOTH_ENABLE
-#    ifdef BLUETOOTH_BLUEFRUIT_LE
-#        include "bluefruit_le.h"
-#        define bluetooth_is_connected() bluefruit_le_is_connected()
-#    else
-// TODO: drivers should check if BT is connected here
-#        define bluetooth_is_connected() true
-#    endif
-#endif
 
 #define CONNECTION_HOST_INVALID 0xFF
 

tmk_core/protocol/host.c

···
 #    include "joystick.h"
 #endif
 
+#ifdef CONNECTION_ENABLE
+#    include "connection.h"
+#endif
+
 #ifdef BLUETOOTH_ENABLE
-#    ifndef CONNECTION_ENABLE
-#        error CONNECTION_ENABLE required and not enabled
-#    endif
-#    include "connection.h"
 #    include "bluetooth.h"
+
+static void bluetooth_send_extra(report_extra_t *report) {
+    switch (report->report_id) {
+        case REPORT_ID_SYSTEM:
+            bluetooth_send_system(report->usage);
+            return;
+        case REPORT_ID_CONSUMER:
+            bluetooth_send_consumer(report->usage);
+            return;
+    }
+}
+
+host_driver_t bt_driver = {
+    .keyboard_leds = bluetooth_keyboard_leds,
+    .send_keyboard = bluetooth_send_keyboard,
+    .send_nkro     = bluetooth_send_nkro,
+    .send_mouse    = bluetooth_send_mouse,
+    .send_extra    = bluetooth_send_extra,
+};
 #endif
 
 #ifdef NKRO_ENABLE
···
     return driver;
 }
 
+static host_driver_t *host_get_active_driver(void) {
+#ifdef CONNECTION_ENABLE
+    switch (connection_get_host()) {
+#    ifdef BLUETOOTH_ENABLE
+        case CONNECTION_HOST_BLUETOOTH:
+            return &bt_driver;
+#    endif
+        case CONNECTION_HOST_NONE:
+            return NULL;
+        default:
+            break;
+    }
+#endif
+    return driver;
+}
+
 #ifdef SPLIT_KEYBOARD
 uint8_t split_led_state = 0;
 void    set_split_host_keyboard_leds(uint8_t led_state) {
···
 #ifdef SPLIT_KEYBOARD
     if (!is_keyboard_master()) return split_led_state;
 #endif
-    if (!driver) return 0;
+
+    host_driver_t *driver = host_get_active_driver();
+    if (!driver || !driver->keyboard_leds) return 0;
+
     return (*driver->keyboard_leds)();
 }
 
···
 
 /* send report */
 void host_keyboard_send(report_keyboard_t *report) {
-#ifdef BLUETOOTH_ENABLE
-    if (connection_get_host() == CONNECTION_HOST_BLUETOOTH) {
-        bluetooth_send_keyboard(report);
-        return;
-    }
-#endif
+    host_driver_t *driver = host_get_active_driver();
+    if (!driver || !driver->send_keyboard) return;
 
-    if (!driver) return;
 #ifdef KEYBOARD_SHARED_EP
     report->report_id = REPORT_ID_KEYBOARD;
 #endif
···
 }
 
 void host_nkro_send(report_nkro_t *report) {
-    if (!driver) return;
+    host_driver_t *driver = host_get_active_driver();
+    if (!driver || !driver->send_nkro) return;
+
     report->report_id = REPORT_ID_NKRO;
     (*driver->send_nkro)(report);
 
···
 }
 
 void host_mouse_send(report_mouse_t *report) {
-#ifdef BLUETOOTH_ENABLE
-    if (connection_get_host() == CONNECTION_HOST_BLUETOOTH) {
-        bluetooth_send_mouse(report);
-        return;
-    }
-#endif
+    host_driver_t *driver = host_get_active_driver();
+    if (!driver || !driver->send_mouse) return;
 
-    if (!driver) return;
 #ifdef MOUSE_SHARED_EP
     report->report_id = REPORT_ID_MOUSE;
 #endif
···
     if (usage == last_system_usage) return;
     last_system_usage = usage;
 
-    if (!driver) return;
+    host_driver_t *driver = host_get_active_driver();
+    if (!driver || !driver->send_extra) return;
 
     report_extra_t report = {
         .report_id = REPORT_ID_SYSTEM,
···
     if (usage == last_consumer_usage) return;
     last_consumer_usage = usage;
 
-#ifdef BLUETOOTH_ENABLE
-    if (connection_get_host() == CONNECTION_HOST_BLUETOOTH) {
-        bluetooth_send_consumer(usage);
-        return;
-    }
-#endif
-
-    if (!driver) return;
+    host_driver_t *driver = host_get_active_driver();
+    if (!driver || !driver->send_extra) return;
 
     report_extra_t report = {
         .report_id = REPORT_ID_CONSUMER,