Implement new 'raw' input type for E1 timeslots
In the past, the A-bis E1 input system only unederstood LAPD signalling
time-slots and trau-slots with 16kBps sub-slots. This adds the notion
of a 'raw' transparent 64kBps slot, without any furthe de-multiplexing
nor any HLDC inside.
Change-Id: I0c25c2688eddd0c55c15b280a8c6e8a49629516b
diff --git a/src/input/dahdi.c b/src/input/dahdi.c
index ab06908..db00f5f 100644
--- a/src/input/dahdi.c
+++ b/src/input/dahdi.c
@@ -360,6 +360,79 @@
return ret;
}
+/* write to a raw channel TS */
+static int handle_ts_raw_write(struct osmo_fd *bfd)
+{
+ struct e1inp_line *line = bfd->data;
+ unsigned int ts_nr = bfd->priv_nr;
+ struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+ struct msgb *msg;
+ int ret;
+
+ /* get the next msg for this timeslot */
+ msg = e1inp_tx_ts(e1i_ts, NULL);
+ if (!msg)
+ return 0;
+
+ if (msg->len != D_BCHAN_TX_GRAN) {
+ /* This might lead to a transmit underrun, as we call tx
+ * from the rx path, as there's no select/poll on dahdi
+ * */
+ LOGP(DLINP, LOGL_NOTICE, "unexpected msg->len = %u, "
+ "expected %u\n", msg->len, D_BCHAN_TX_GRAN);
+ }
+
+ DEBUGP(DLMIB, "RAW CHAN TX: %s\n",
+ osmo_hexdump(msg->data, msg->len));
+
+ if (0/*invertbits*/) {
+ flip_buf_bits(msg->data, msg->len);
+ }
+
+ ret = write(bfd->fd, msg->data, msg->len);
+ if (ret < msg->len)
+ LOGP(DLINP, LOGL_DEBUG, "send returns %d instead of %d\n",
+ ret, msg->len);
+ msgb_free(msg);
+
+ return ret;
+}
+
+static int handle_ts_raw_read(struct osmo_fd *bfd)
+{
+ struct e1inp_line *line = bfd->data;
+ unsigned int ts_nr = bfd->priv_nr;
+ struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+ struct msgb *msg = msgb_alloc(D_TSX_ALLOC_SIZE, "DAHDI Raw TS");
+ int ret;
+
+ if (!msg)
+ return -ENOMEM;
+
+ ret = read(bfd->fd, msg->data, D_TSX_ALLOC_SIZE);
+ if (ret < 0 || ret != D_TSX_ALLOC_SIZE) {
+ LOGP(DLINP, LOGL_DEBUG, "read error %d %s\n",
+ ret, strerror(errno));
+ return ret;
+ }
+
+ if (0/*invertbits*/) {
+ flip_buf_bits(msg->data, ret);
+ }
+
+ msgb_put(msg, ret);
+
+ msg->l2h = msg->data;
+ DEBUGP(DLMIB, "RAW CHAN RX: %s\n",
+ osmo_hexdump(msgb_l2(msg), ret));
+ ret = e1inp_rx_ts(e1i_ts, msg, 0, 0);
+ /* physical layer indicates that data has been sent,
+ * we thus can send some more data */
+ ret = handle_ts_raw_write(bfd);
+
+ return ret;
+}
+
/* callback from select.c in case one of the fd's can be read/written */
static int dahdi_fd_cb(struct osmo_fd *bfd, unsigned int what)
{
@@ -389,6 +462,17 @@
* writeset, since it doesn't support poll() based
* write flow control */
break;
+ case E1INP_TS_TYPE_RAW:
+ if (what & BSC_FD_EXCEPT)
+ handle_dahdi_exception(e1i_ts);
+ if (what & BSC_FD_READ)
+ rc = handle_ts_raw_read(bfd);
+ if (what & BSC_FD_WRITE)
+ rc = handle_ts_raw_write(bfd);
+ /* We never include the DAHDI B-Channel FD into the
+ * writeset, since it doesn't support poll() based
+ * write flow control */
+ break;
default:
LOGP(DLINP, LOGL_NOTICE,
"unknown E1 TS type %u\n", e1i_ts->type);
@@ -537,6 +621,7 @@
e1i_ts, &lapd_profile_abis);
break;
case E1INP_TS_TYPE_TRAU:
+ case E1INP_TS_TYPE_RAW:
/* close/release LAPD instance, if any */
if (e1i_ts->lapd) {
lapd_instance_free(e1i_ts->lapd);