Using both MNCC_FRAME RECV/DROP messages, an external MNCC
application could enable / disable forwarding of the traffic
frames from L1 through MNCC-socket.
Now it can be done by user from the VTY configuration (see
'io-target' of 'audio' section), so there is no need to
control this from outside.
Change-Id: I41a0c9bc44b3ca6784f4190931773637f9fab40c
This message is used to negotiate MNCC protocol version, and also
in order to make sure that the sutructure alignment is equivalent
for both sides.
Change-Id: I7c5d8aa17540dd61bbe003a6468d97ecea415636
This change introduces a new feature of the mobile application -
audio I/O support, which allows one to speak right from PC running
mobile through its ordinary mic and speakers.
The audio I/O is based on GAPK library, which relays on ALSA sound
framework. The API of GAPK implies to use the processing queues
(chains), which basically consist of a source block, several
processing blocks, and a sink block. So, there are two voice
processing chains:
- 'pq_audio_source' (voice capture -> frame encoding),
- 'pq_audio_sink' (frame decoding -> voice playback).
Both of them exchange frames from two dedicated buffers:
- 'tch_fb_ul' - a buffer for to be played DL TCH frames,
- 'tch_fb_dl' - a buffer for encoded UL TCH frames.
In its turn, both buffers are served by a new gapk_io_dequeue()
function, which is being called within the mobile_work() loop.
Change-Id: Ib86b0746606c191573cc773f01172afbb52f33a9
It was assumed that only FR frames (with magic 0xd) can be carried
by the L1CTL_TRAFFIC messages, but there are also EFR, HR, and AMR
frames, and dropping them is not a good idea.
Change-Id: I4b7b85d94f11deb7525b63f3549a182c6e76da08
At the moment, both 'l1ctl_traffic_req' and 'l1ctl_traffic_ind'
don't have any fields, but in the near future they may be
modified to carry some important information.
Let's restore this header in the L1CTL_TRAFFIC messages.
Change-Id: I8074527149de63655e33dbe3ad7c413d3f8af2b2
Unlike the LAPDm messages, traffic frames may have different
length. Instead of having a buffer with fixed length, let's
use flexible array member. This would allow one to calculate
a frame length using the MSGB API (i.e. msgb_l3len()).
Change-Id: I119fa36c84e95c3003d57c19e25f8146ed45c3c6
According to 3GPP TS 04.08, section 3.4.6.1.3 "Abnormal cases"
of "channel mode modify procedure", if the MS doesn't support
the indicated channel mode, it shall retain the old mode and
return the associated channel mode information in the
ACKNOWLEDGE message.
Previously, if an indicated mode is not supported, we used to
indicate the 'CHAN_MODE_UNACCT' RR case without sending the
ACKNOWLEDGE message. Also, the result of gsm48_rr_set_mode()
was ignored. Let's fix this!
Change-Id: I952436ec796273e56341f9d3492b4a3b3a5dc410
The CHANNEL MODE MODIFY message only applies to TCH channels,
and in general should not arrive on non-traffic channels. Let's
print error message if this happens in order to facilitate
finding possible bugs.
Change-Id: I4ab63c4ae4262c8166de37e4873fc3f1b8ec6fe7
The rsl_dec_chan_nr() may fail to decode RSL channel number, so
the 'ch_type' variable would be uninitialized. Let's check rc.
Change-Id: I9ab18bdaf41a29fcd32a7060668ef9db07b8cf7e
In the prevoius change a new configuration option was introduced
as a part of new 'audio' node - 'io-target'. This change makes it
to take an effect, instructing the L1 to use one of the following
possible TCH frame I/O targets:
- gapk - build-in (WIP) GAPK-based audio back-end (default);
- hardware - L1 hardware (e.g. Calypso DSP);
- socket - External MNCC application (e.g. LCR).
Change-Id: I2a36d9c30da6746995dcea3a33cb13e0d2f6549a
This change introduces a new node named 'AUDIO', which is intended
to organize some audio related settings, such as:
- io-target - TCH frame I/O back-end (e.g. gapk, hardware);
- alsa-output-dev - ALSA playback (i.e. speakers) device name;
- alsa-input-dev - ALSA recording (i.e. mic) device name.
The last two are actual when 'io-target' is set to 'gapk'.
For now, all introduced parameters don't affect anything.
Change-Id: I62cd5ef22ca2290fcafe65c78537ddbcb39fb8c6
Since GAPK has became a shared library - libosmogapk, it can be
used for the voice capture / playback directly on the host side.
This change adds the library as a dependency, and links
the mobile application against it.
Change-Id: I47054f32fec6780bdbe6f73b82aa446c4c7c1df4
Since the mobile application is potentionally able to work with
multiple MS instances, it's better to have a possibility to
choose an MNCC (Call Control) handler per each MS separately.
This change cleans up the code, removing a dedicated command-line
option '-m' intended for enabling extarnal MNCC. Now it's possible
to set an MNCC-handler for each MS via VTY interface and settings.
The following MNCC-handlers are available:
- mobile - build-in MNCC-handler (default);
- socket - external MNCC-handler via UNIX-socket (e.g. LCR);
- dummy - dummy handler without CC support.
Change-Id: I2df91c7a79ba5c39bc6ceae900ef649129dd0346
Previously the MNCC socket path was generated automatically,
using concatenation of the '/tmp/ms_mncc_' prefix and MS name.
Let's allow user to specify this manually, keeping a similar
generation method for default value.
Change-Id: I643356ac579bc5e765f668265ec803b22a73739c
This change extends sched_trx_chan_nr2pchan_config() with Osmocom
specific cbits related to CBCH, so now one can to decode
CBCH channels in dedicated mode (see L1CTL_DM_EST_REQ).
Change-Id: I9347c45638223cac34f4b48eb736e51a5055a36f
According to GSM TS 05.02, there are two ways to enable CBCH:
a) replace sub-slot number 2 of CCCH+SDCCH/4 (comb. V),
b) replace sub-slot number 2 of SDCCH/8 (comb. VII).
Unlike SDCCH/8 (case b), CCCH+SDCCH/4 can be allocated on TS0
only, and shall not use frequency hopping. This means that
implementing CBCH support on SDCCH/8 would require much more
efforts than on combined CCCH+SDCCH/4, as in last case CBCH
messages can be received without the need to switch from
idle to dedicated mode.
This change introduces a new ccch_mode item, which should be
used by the higher layers to indicate presence of CBCH channel
on C0/TS0, so the PHY would enable decoding of CBCH messages
on CCCH+SDCCH/4 (case a) in idle mode.
Regarding to CBCH on SDCCH/8 (case b), it makes sense to
extend the 'l1ctl_dm_est_req', so it would be handled in
dedicated mode on request from the higher layers.
Change-Id: Ia94ebf22a2ec439dfe1f31d703b832ae57b48ef2
According to GSM TS 05.02, section 3.3.5, Cell Broadcast Channel
(CBCH) is a downlink only channel, which is used to carry the
short message service cell broadcast (SMSCB). CBCH is optional,
and uses the same physical channel as SDCCH. More precisely,
CBCH replaces sub-slot number 2 of SDCCH channels when enabled.
This change introduces the CBCH enabled multi-frame layouts,
and two separate logical channel types:
- GSM_PCHAN_CCCH_SDCCH4_CBCH (lchan TRXC_SDCCH4_CBCH),
- GSM_PCHAN_SDCCH8_SACCH8C_CBCH (lchan TRXC_SDCCH8_CBCH).
Both logical channels are separately identified using
the following Osmocom specific cbits:
- TRXC_SDCCH4_CBCH - 0x18 (0b11000),
- TRXC_SDCCH8_CBCH - 0x19 (0b11001).
The reason of this separation is that we somehow need to
distinguish between CBCH on C0/TS0, and CBCH on CX/TS0.
Unlike TRXC_SDCCH8_CBCH, TRXC_SDCCH4_CBCH is enabled
automatically (TRX_CH_FLAG_AUTO), so CBCH messages
can be decoded on C0 while being in idle mode.
Change-Id: Iad9905fc3a8a012ff1ada26ff95af384816f9873
According to GSM TS 05.02, section 3.3.5, Cell Broadcast Channel
(CBCH) is a downlink only channel, which is used to carry the
short message service cell broadcast (SMSCB). CBCH is optional,
and uses the same physical channel as SDCCH. More precisely,
CBCH replaces sub-slot number 2 of SDCCH channels when enabled.
This change introduces the following CBCH related tasks:
- MF_TASK_SDCCH4_CBCH (CBCH on C0/TS0 SDCCH/4),
- MF_TASK_SDCCH8_CBCH (CBCH on SDCCH/8),
which are identified using the following Osmocom specific cbits:
- MF_TASK_SDCCH4_CBCH - 0x18 (0b11000),
- MF_TASK_SDCCH8_CBCH - 0x19 (0b11001).
The only way to enable these tasks at the moment is to send
L1CTL_DM_EST_REQ message with required cbits and tn.
Change-Id: I1d7f02cba1cd8f6527360589d2d2747b6426f78b
The mframe_task2chan_nr() is used to get the channel number
(encoded according to 08.58 Chapter 9.3.1) corresponding to
a given multi-frame task type.
It makes sense to at least print some debug message in cases
when there is no matching channel number for a given task type.
Change-Id: I34587b6c67015513de35d85a7a3291f452ee7f3b
The 'ccch_mode' enum from 'l1ctl_proto.h' to be extended in the
near future in order to reflect persistence of CBCH. Thus it
should be handled in a switch statement.
Change-Id: I75e3b8deac1da296efb178e65ff6992b5c407b80
According to GSM TS 08.58, chapter 9.3.1, channel number 0x08
describes sub-slot number 0 of SDCCH/8+ACCH. This is definitely
wrong. In OsmoBTS we use an Osmocom specific extension for packet
switched channels - 0xc0, so let's use it here too.
Change-Id: I11925408d6e63baf1eac880839ecd717843fba6a
In some conditions it's required to maintain continuous burst
transmission (e.g. on C0). If there is nothing to transmit at
a given moment, either a LAPDm func=UI fill frame,
or a "dummy" Paging Request is used.
In case of 'ccch_scan' application, they are useless.
Let's detect and omit them.
Change-Id: I6ccecb1a78bdac3e467bdc14b7a01afbe17aa53c
By definition, 'ccch_scan' application is intended to be used for
monitoring of CCCH channels on C0/TS0. There is no need to send
RACH requests, therefore there is no need to care about the
mobile allocation from SI1 message.
Most likely, this "dead" code was copy-pasted from mobile
application. Let's clean it up!
Change-Id: I7c2f47cbc825a5e5a50863d842729d3d8408b9dd
According to 3GPP TS 04.08, section 3.4.1, SACCH logical channel
accompanies either a traffic or a signaling channel. It has the
particularity that continuous transmission must occur in both
directions, so on the Uplink direction measurement result messages
are sent at each possible occasion when nothing else has to be sent.
The LAPDm fill frames (0x01, 0x03, 0x01, 0x2b, ...) are not
applicable on SACCH channels!
Unfortunately, 3GPP TS 04.08 doesn't clearly state which "else
messages" besides Measurement Reports can be send by the MS on
SACCH channels. However, in sub-clause 3.4.1 it's stated that
the interval between two successive measurement result messages
shall not exceed one L2 frame.
This change introduces a separate handler for SACCH primitives,
which dequeues a SACCH primitive from transmit queue, if present.
Otherwise it dequeues a cached Measurement Report (the last
received one). Finally, if the cache is empty, a "dummy"
measurement report is used. When it's possible,
a non-MR primitive is prioritized.
Change-Id: If1b8dc74ced746d6270676fdde75fcda32f91a3d
Related: OS#2988
Enforcing pointer to a 'trx_instance' structure is not flexible,
because it is used as parent talloc context only.
Change-Id: I5ab2ef5cea76f955bf72ef54541b3b75cdc2d23f
Having access to a logical channel state is required by the
follow-up change, which will introduce a separate function
for dequeuing SACCH primitives.
Change-Id: Ibde0acf8e6be224b1007be707a636eaad68c8d36
Unlike xCCH, TCH/H channels are using block diagonal interleaving,
so every single burst carries 57 bits of one traffic frame, and 57
bits of another one. Moreover, unlike TCH/F where both traffic
and FACCH/F frames are interleaved over 8 bursts, a FACCH/H is
interleaved over 6 bursts, while a traffic frame is interleaved
over 4 bursts.
This is why a TCH/H burst transmission can't be initiated on
an arbitrary TDMA frame number. It shall be aligned as of
stated in GSM 05.02, clause 7, table 1.
This change introduces two basic functions:
- sched_tchh_block_map_fn - checks if a TCH/H block transmission
can be initiated / finished on a given frame number
and a given channel type;
- sched_tchh_block_dl_first_fn - calculates TDMA frame number of
the first burst using given frame number of the last burst;
and some auxiliary wrappers to simplify the usage of
sched_tchh_block_map_fn().
Change-Id: Iaf4cb33f1b79df23f8a90c8b14ebe0cd9907fbb9
Vadim Yanitskiy
Harald Welte