Hi Luiz, On Thu, May 08, 2014 at 04:51:48PM +0300, Luiz Augusto von Dentz wrote: > Hi Andrei, > > On Thu, May 8, 2014 at 3:25 PM, Andrei Emeltchenko > <Andrei.Emeltchenko.news@xxxxxxxxx> wrote: > > From: Andrei Emeltchenko <andrei.emeltchenko@xxxxxxxxx> > > > > For synchronization interleave read() and write(). > > --- > > android/hal-sco.c | 73 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 73 insertions(+) > > > > diff --git a/android/hal-sco.c b/android/hal-sco.c > > index 7b6608b..5ec56ce 100644 > > --- a/android/hal-sco.c > > +++ b/android/hal-sco.c > > @@ -41,6 +41,8 @@ > > #define OUT_BUFFER_SIZE 2560 > > #define OUT_STREAM_FRAMES 2560 > > > > +#define SOCKET_POLL_TIMEOUT_MS 500 > > + > > static int listen_sk = -1; > > static int audio_sk = -1; > > > > @@ -275,6 +277,74 @@ static void downmix_to_mono(struct sco_stream_out *out, const uint8_t *buffer, > > } > > } > > > > +static bool write_data(struct sco_stream_out *out, const uint8_t *buffer, > > + size_t bytes) > > +{ > > + struct pollfd pfd; > > + size_t len, written = 0; > > + int ret; > > + uint16_t mtu = /* out->cfg.mtu */ 48; > > + uint8_t read_buf[mtu]; > > + bool do_write = false; > > + > > + pfd.fd = out->fd; > > + pfd.events = POLLOUT | POLLIN | POLLHUP | POLLNVAL; > > + > > + while (bytes > written) { > > + > > + /* poll for sending */ > > + if (poll(&pfd, 1, SOCKET_POLL_TIMEOUT_MS) == 0) { > > + DBG("timeout fd %d", out->fd); > > + return false; > > + } > > + > > + if (pfd.revents & (POLLHUP | POLLNVAL)) { > > + error("error fd %d, events 0x%x", out->fd, pfd.revents); > > + return false; > > + } > > + > > + if (pfd.revents & POLLIN) { > > + ret = read(out->fd, read_buf, mtu); > > + if (ret < 0) { > > + error("Error reading fd %d (%s)", out->fd, > > + strerror(errno)); > > + return false; > > + } > > + > > + do_write = true; > > You probably gonna have store the read data in a buffer to be read by > upper layer after remixed to 44.1 KHz, to safe space you can probably > leave the remixing to be done on the read callback. Im fine to do this > in a separate patch but we should at least add a comment about it. I think we need to have special thread which does read-write since Android might call read() without write(). Best regards Andrei Emeltchenko -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html