Since 95407f3f osmo-bts-trx supports scheduling all CSD specific
channel rates, however the rate adaptation was missing.
On the radio interface we deal with CSD-modified V.110 frames, which
need to be converted to normal 80-bit V.110 frames (RA1'/RA1), which
in turn need to be batched and sent in RFC4040 "clearmode" 160 octet
RTP payloads (RA1/RA2 as per I.460).
Note that this patch comments out TCH/F14.4 in bts_supports_cm_data(),
so that all channel allocations for this mode would be NACKed. The
reason for this is that the rate adaptation functions for TCH/F14.4
are different than the RA1'/RA1 and the RA1/RA2.
For more information, see:
* 3GPP TS 44.021, section 8 (functions RA1'/RA1)
* ITU-T I.460, section 1.1 "Rate adaption of 8, 16 and 32 kbit/s streams"
Change-Id: I5e3701ad52d5d428fd02caff037881045f2d0a02
Related: OS#1572
Vadim Yanitskiy
d1f8f3429c