* add trau_mux implementation to relay from one incoming TRAU
channel to another one (simple voice call switching)
* add a way more generic E1 input layer, abstracting out the misdn
low-level interface. This also adds infrastructure for multiple TRX
in one BTS, as well as multiple BTS on one E1 link
* add a E1 subchannel multiplexer for sending multiple 16kbit sub-channels
one one 64kBps E1 channel
* add TRAU IDLE frame generation
* terminate bsc_hack in case there is a E1 / mISDN init error
* introduce 'e1_config.c' file with static configuration of our
E1 setup (which TRX/BTS is configured for which TEI/SAPI/E1). This should
later become a config file rather than a compiled C file.
WARNING: all this compiles but is not tested yet. Expect fix-up committs over
the next hours or so
diff --git a/include/openbsc/subchan_demux.h b/include/openbsc/subchan_demux.h
index 373cf4a..23c9032 100644
--- a/include/openbsc/subchan_demux.h
+++ b/include/openbsc/subchan_demux.h
@@ -1,6 +1,6 @@
#ifndef _SUBCH_DEMUX_H
#define _SUBCH_DEMUX_H
-/* A E1 sub-channel demultiplexer with TRAU frame sync */
+/* A E1 sub-channel (de)multiplexer with TRAU frame sync */
/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
* All Rights Reserved
@@ -22,26 +22,77 @@
*/
#include <sys/types.h>
+#include <openbsc/linuxlist.h>
#define NR_SUBCH 4
#define TRAU_FRAME_SIZE 40
#define TRAU_FRAME_BITS (TRAU_FRAME_SIZE*8)
-struct subch {
+/***********************************************************************/
+/* DEMULTIPLEXER */
+/***********************************************************************/
+
+struct demux_subch {
u_int8_t out_bitbuf[TRAU_FRAME_BITS];
u_int8_t out_idx; /* next bit to be written in out_bitbuf */
};
struct subch_demux {
+ /* bitmask of currently active subchannels */
u_int8_t chan_activ;
- struct subch subch[NR_SUBCH];
+ /* one demux_subch struct for every subchannel */
+ struct demux_subch subch[NR_SUBCH];
+ /* callback to be called once we have received a complete
+ * frame on a given subchannel */
int (*out_cb)(struct subch_demux *dmx, int ch, u_int8_t *data, int len,
void *);
+ /* user-provided data, transparently passed to out_cb() */
void *data;
};
+/* initialize one demultiplexer instance */
int subch_demux_init(struct subch_demux *dmx);
+
+/* feed 'len' number of muxed bytes into the demultiplexer */
int subch_demux_in(struct subch_demux *dmx, u_int8_t *data, int len);
+
+/* activate decoding/processing for one subchannel */
int subch_demux_activate(struct subch_demux *dmx, int subch);
+
+/* deactivate decoding/processing for one subchannel */
int subch_demux_deactivate(struct subch_demux *dmx, int subch);
+
+/***********************************************************************/
+/* MULTIPLEXER */
+/***********************************************************************/
+
+/* one element in the tx_queue of a muxer sub-channel */
+struct subch_txq_entry {
+ struct llist_head list;
+
+ unsigned int bit_len; /* total number of bits in 'bits' */
+ unsigned int next_bit; /* next bit to be transmitted */
+
+ u_int8_t bits[0]; /* one bit per byte */
+};
+
+struct mux_subch {
+ struct llist_head tx_queue;
+};
+
+/* structure representing one instance of the subchannel muxer */
+struct subch_mux {
+ struct mux_subch subch[NR_SUBCH];
+};
+
+/* initialize a subchannel muxer instance */
+int subchan_mux_init(struct subch_mux *mx);
+
+/* request the output of 'len' multiplexed bytes */
+int subchan_mux_out(struct subch_mux *mx, u_int8_t *data, int len);
+
+/* enqueue some data into one sub-channel of the muxer */
+int subchan_mux_enqueue(struct subch_mux *mx, int s_nr, const u_int8_t *data,
+ int len);
+
#endif /* _SUBCH_DEMUX_H */