Handsfree device not able to receive any audio from sco socket - audio

Question

I am developing a handsfree module, in which after completing service level connection I am setting up sco connection with phone's audio gateway and receive audio data as below...
void audio_connection_setup(char *bluetooth_addr)
{
struct sockaddr_sco addr;
pthread_t tid;
int scoSock = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_SCO);
memset(&addr, 0, sizeof(addr));
addr.sco_family = AF_BLUETOOTH;
addr.sco_bdaddr = *BDADDR_ANY;
if (bind(scoSock, (struct sockaddr *) &addr, sizeof(addr)) < 0)
{
printf( "Can't bind socket: %s (%d)",strerror(errno), errno);
}
hci_read_voice_setting(scoSock, &voice, 5000);
hci_write_voice_setting(scoSock, BT_VOICE_CVSD_16BIT, 5000);
str2ba(bluetooth_addr, &addr.sco_bdaddr);
if (connect(scoSock, (struct sockaddr *) &addr, sizeof(addr)) < 0)
{
printf( "\nCan't connect: %s (%d)", strerror(errno), errno);
}
pthread_create(&tid, NULL, &read_data, &scoSock);
}
Here is the read_data thread
gBuff[16284];
void* read_data(int *scoSock)
{
int fd = *scoSock;
int len = -1;
char buff[48];
int numBytesRead;
while (1)
{
numBytesRead = 0;
while(numBytesRead < 16284)
{
memset(buff, 0x0, 48);
len = recv(fd, buff, 48, MSG_DONTWAIT);
usleep(10);
memcpy(gBuff + numBytesRead, buff + 2, len - 2);
numBytesRead = numBytesRead + len - 2;
}
printf("Number of bytes received = %d errno = %d\n", numBytesRead, errno);
memset(gBuff, 0x0, numBytesRead);
}
}
This code is working fine if I run it on linux PC, But when i run on arm board the recv system call returns errno EAGAIN in continuous loop and never comes out. On PC the recv system call returns number of bytes properly. What may be possible cause to this issue?

Answer 1

I think the reason should be when your code runs on the pc, you may get the audio data from HCI link, i.e. the HF sco over HCI and then you transfer it to PC driver. However when you switch to board, I wonder whether the board's hardware Bluetooth interface lets say UART, whether it has high throughput to transfer the sco data, and most importantly, you need check whether the sco data was routed to PCM interface i.e. does not sending to HCI.