Add A2DP_INIT command and state.

In bluez4, when a device is unpaired the socket end is freed and
so we will get a EPIPE when we write to it, this causes us to call
bluetooth_close. On the next write, we don't call bluetooth_init.

The logic here is thati, if the state is A2DP_STATE_NONE and we
are waiting for BLUETOOTH_START state, we need to call bluetooth_init.
The ENODEV case is where the other end, doesn't exist, and we are
trying to write repeatedly, which means the problem is elsewhere.
When we start initially (i.e the first time) when a2dp_set_sink is called,
we used to directly set the command to configure and the a2dp_thread used to
call bluetooth_init. This fix makes this a separate state and step.
Tested:
  1. A2DP music playing, turn BT off. Turn BT open, A2DP should work.
  2. A2DP music playing, disconnect. On reconnection, it should work.
  3. A2DP music playing, cause a crash in bluetoothd. On restart, it should
     work.
  4. A2DP music playing, remote end powers down. On power up, it should work.
  5. A2DP music playing, disconnect and unpair. On repair and reconnect,
     it should work.
Tested with 2 headsets and with the troublesome HBH-DS790.

1 files changed, 8 insertions, 6 deletions

diff --git a/audio/liba2dp.c b/audio/liba2dp.c
index 001a964e..3300ec72 100755
--- a/audio/liba2dp.c
+++ b/audio/liba2dp.c
@@ -101,6 +101,7 @@ typedef enum {
 
 typedef enum {
 	A2DP_CMD_NONE = 0,
+	A2DP_CMD_INIT,
 	A2DP_CMD_CONFIGURE,
 	A2DP_CMD_START,
 	A2DP_CMD_STOP,
@@ -911,7 +912,7 @@ static int wait_for_start(struct bluetooth_data *data, int timeout)
 
 	while (state != A2DP_STATE_STARTED && !err) {
 		if (state == A2DP_STATE_NONE)
-			return -ENODEV;
+			set_command(data, A2DP_CMD_INIT);
 		else if (state == A2DP_STATE_INITIALIZED)
 			set_command(data, A2DP_CMD_CONFIGURE);
 		else if (state == A2DP_STATE_CONFIGURED)
@@ -949,10 +950,12 @@ static void* a2dp_thread(void *d)
 		command = data->command;
 		pthread_mutex_unlock(&data->mutex);
 
-		if (data->state == A2DP_STATE_NONE && command != A2DP_CMD_QUIT)
-			bluetooth_init(data);
-
 		switch (command) {
+			case A2DP_CMD_INIT:
+				if (data->state != A2DP_STATE_NONE)
+					break;
+				bluetooth_init(data);
+				break;
 			case A2DP_CMD_CONFIGURE:
 				if (data->state != A2DP_STATE_INITIALIZED)
 					break;
@@ -1032,8 +1035,7 @@ void a2dp_set_sink(a2dpData d, const char* address)
 	struct bluetooth_data* data = (struct bluetooth_data*)d;
 	if (strncmp(data->address, address, 18)) {
 		strncpy(data->address, address, 18);
-		// force reconfiguration
-		set_command(data, A2DP_CMD_CONFIGURE);
+		set_command(data, A2DP_CMD_INIT);
 	}
 }