read and write flash without entering into DFU mode

I have writen a C program to write and read from flash in a Bluetooth chip(CSR). However, I have to entering into the DFU mode to read and write from flash. Is it possible to read and write from flash without entering into the DFU mode? I have to press the button to entering into the DFU mode, which is time consuming for mass production.

int test_read_cmd(void)
{
int ret;
int i;
static const unsigned int addr[] = { 0x00000010, 0x00000020, 0x00000030, };
static const unsigned char rlen[sizeof(addr) / sizeof(addr[0])] = { 1, 4, 
16, };
unsigned char b[16];

for (i = 0; i < sizeof(rlen); i++) {
    ret = read_cmd(addr[i], rlen[i], b);
    if (ret) {
        return ret;
    }
}

return 0;
}

int read_cmd(unsigned int addr, unsigned int len, unsigned char *data)
{
int ret;
unsigned char b[17];
size_t reply_len;

//TRACE("--- Send READ msg addr=0x%08x len=%d ---", addr, len);

if (len > 16) {
    TRACE("READ msg length too long: %d", len);
    return 1;
}

comm_state = COMM_READ;

memcpy(&b[0], &addr, 4);
b[4] = len;

ret = send_packet(b, 5, TYPE_READ, send_seq++);
if (ret) {
    TRACE("Sending READ %d failed", len);
    return ret;
}

//TRACE("--- Recv READ %d reply msg ---", len);

ret = recv_reply(b, 1 + len, &reply_len);
if (ret) {
    TRACE("Receiving READ %d reply failed", len);
    return ret;
}

if (b[0] != ERR_NONE) {
    TRACE("READ %d reply error 0x%x", len, b[0]);
    return 1;
}

memcpy(data, &b[1], len);

//dump_buffer(data, len);

return 0;
}