fix: connect A2DP after pairing and enable JustWorksRepairing for BT headsets

skeleton/SYSTEM/tg5040/etc/bluetooth/bt_init.sh

@@ -44,6 +44,14 @@ start_bt() {
 		start_hci_attach
 	fi
 
+	# Allow headsets to auto-reconnect without user re-pairing.
+	# XRadio BT firmware sets store_hint=0, so link keys are never
+	# persisted; JustWorksRepairing=always lets earbuds re-initiate
+	# the bond from their side after a reboot.
+	if ! grep -q 'JustWorksRepairing = always' /etc/bluetooth/main.conf 2>/dev/null; then
+		sed -i 's/.*JustWorksRepairing.*/JustWorksRepairing = always/' /etc/bluetooth/main.conf 2>/dev/null
+	fi
+
 	# Start bluetooth daemon if not running
     d=`ps | grep bluetoothd | grep -v grep`
 	[ -z "$d" ] && {
@@ -69,6 +77,22 @@ start_bt() {
 
 		# Set adapter name
 		bluetoothctl system-alias "$DEVICE_NAME" 2>/dev/null
+
+		# Proactively reconnect trusted A2DP audio devices after BT restart.
+		# Some headphones (e.g. Sony) won't fall back to JustWorks re-pairing
+		# when authentication fails; they expect the host to initiate using the
+		# stored link key. Runs in background to avoid blocking startup.
+		{
+			sleep 5
+			for dev_dir in /var/lib/bluetooth/*/; do
+				for paired_dir in "${dev_dir}"*/; do
+					[ -f "${paired_dir}info" ] || continue
+					grep -q "0000110b" "${paired_dir}info" || continue
+					mac=$(basename "${paired_dir%/}")
+					bluetoothctl connect "$mac" >/dev/null 2>&1
+				done
+			done
+		} &
     }
 
 }

skeleton/SYSTEM/tg5050/etc/bluetooth/bt_init.sh

@@ -52,6 +52,14 @@ start_bt() {
 		start_hci_attach
 	fi      
 
+	# Allow headsets to auto-reconnect without user re-pairing.
+	# Some BT controller firmware never persists link keys to disk;
+	# JustWorksRepairing=always lets earbuds re-initiate the bond
+	# from their side after a reboot without user interaction.
+	if ! grep -q 'JustWorksRepairing = always' /etc/bluetooth/main.conf 2>/dev/null; then
+		sed -i 's/.*JustWorksRepairing.*/JustWorksRepairing = always/' /etc/bluetooth/main.conf 2>/dev/null
+	fi
+
 	# Start bluetooth daemon if not running
     d=`ps | grep bluetoothd | grep -v grep`
 	[ -z "$d" ] && {
@@ -77,8 +85,24 @@ start_bt() {
 
 		# Set adapter name
 		bluetoothctl system-alias "$DEVICE_NAME" 2>/dev/null
+
+		# Proactively reconnect trusted A2DP audio devices after BT restart.
+		# Some headphones (e.g. Sony) won't fall back to JustWorks re-pairing
+		# when authentication fails; they expect the host to initiate using the
+		# stored link key. Runs in background to avoid blocking startup.
+		{
+			sleep 5
+			for dev_dir in /var/lib/bluetooth/*/; do
+				for paired_dir in "${dev_dir}"*/; do
+					[ -f "${paired_dir}info" ] || continue
+					grep -q "0000110b" "${paired_dir}info" || continue
+					mac=$(basename "${paired_dir%/}")
+					bluetoothctl connect "$mac" >/dev/null 2>&1
+				done
+			done
+		} &
     }
-	
+
 }
 
 stop_bt() {

workspace/all/audiomon/audiomon.cpp

@@ -33,12 +33,27 @@ enum DeviceType {
 
 bool use_syslog = false;
 bool running = true;
+static std::string connected_a2dp_mac;
 
 void log(const std::string& msg) {
     if (use_syslog) syslog(LOG_INFO, "%s", msg.c_str());
     else std::cout << msg << std::endl;
 }
 
+static void initBtStateFromAsoundrc() {
+    std::ifstream f(AUDIO_FILE);
+    if (!f) return;
+    std::string content((std::istreambuf_iterator<char>(f)), std::istreambuf_iterator<char>());
+    auto pos = content.find("defaults.bluealsa.device \"");
+    if (pos == std::string::npos) return;
+    pos += strlen("defaults.bluealsa.device \"");
+    auto end = content.find("\"", pos);
+    if (end == std::string::npos) return;
+    connected_a2dp_mac = content.substr(pos, end - pos);
+    log("Restored BT state from .asoundrc: " + connected_a2dp_mac);
+    SetAudioSink(AUDIO_SINK_BLUETOOTH);
+}
+
 void ensureDirExists(const std::string& path) {
     mkdir(path.c_str(), 0755);
 }
@@ -203,6 +218,7 @@ void handleDeviceConnected(DBusConnection* conn, const std::string& path) {
     std::string mac = pathToMac(path);
     if (hasUUID(conn, path, UUID_A2DP)) {
         log("Audio device connected: " + mac);
+        connected_a2dp_mac = mac;
         writeAudioFile(mac, DEVICE_BLUETOOTH);
         SetAudioSink(AUDIO_SINK_BLUETOOTH);
     } else {
@@ -212,8 +228,12 @@ void handleDeviceConnected(DBusConnection* conn, const std::string& path) {
 
 void handleDeviceDisconnected(DBusConnection* conn, const std::string& path) {
     std::string mac = pathToMac(path);
-    if (hasUUID(conn, path, UUID_A2DP)) {
+    // Use cached MAC rather than querying BlueZ: after an abrupt power-off the
+    // device's service cache may already be gone, causing hasUUID to return false
+    // and silently skip the audio switch-back.
+    if (!connected_a2dp_mac.empty() && mac == connected_a2dp_mac) {
         log("Audio device disconnected: " + mac);
+        connected_a2dp_mac.clear();
         clearAudioFile();
         // TODO: we could maintain a stack here, if USBC was connected before and restore that instead
         SetAudioSink(AUDIO_SINK_DEFAULT);
@@ -285,6 +305,7 @@ int main(int argc, char* argv[]) {
     InitSettings();
     // This will be updated as soon as something connects
     SetAudioSink(AUDIO_SINK_DEFAULT);
+    initBtStateFromAsoundrc();
 
     signal(SIGINT, signalHandler);
     signal(SIGTERM, signalHandler);

workspace/all/common/generic_bt.c

@@ -479,6 +479,12 @@ void PLAT_bluetoothPair(char *addr) {
 		}
 	}
 
+	// Connect after pairing to initiate A2DP audio profile.
+	// Some headsets (store_hint=0 controllers) disconnect ~2s after
+	// pairing if the host doesn't open the audio channel first.
+	snprintf(cmd, sizeof(cmd), "bluetoothctl connect %s 2>/dev/null", addr);
+	system(cmd);
+
 	// Remove from discovered list since it's now paired
 	bt_remove_discovered_device(addr);
 }