diff options
Diffstat (limited to 'include/openbsc/subchan_demux.h')
| -rw-r--r-- | include/openbsc/subchan_demux.h | 57 |
1 files changed, 54 insertions, 3 deletions
diff --git a/include/openbsc/subchan_demux.h b/include/openbsc/subchan_demux.h index 373cf4a30..23c903204 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 */ |