lapdm: don't enforce contention resolution on SAPI0/DCCH
In Change-Id: I8c2c103cdc7f9a45d7b2080c572f559fc3db58e4 we introduced
a check to enforce contention resolution always being used in
MS-originated LAPDm establishment on the main DCCH / SAPI0. This is
only required after RACH request (IMM.ASS.) and not after a normal
assignment command which was sent already via a dedicated channel.
Hence, we cannot enforce a strict requirement for contention resolution
in those cases.
We *could* use the RSL Channel Activation type as a constraint on
whether or not to enforce contention-resoluiton-only LAPDm
establishment, but this is out of the scope of the LAPDm code but would
have to be done inside OsmoBTS.
Related: OS#3252
Change-Id: Id903492ee90809fe98defcf4abc0419b8150069f
diff --git a/src/gsm/lapdm.c b/src/gsm/lapdm.c
index b9e7304..3a6fc5b 100644
--- a/src/gsm/lapdm.c
+++ b/src/gsm/lapdm.c
@@ -552,16 +552,13 @@
return RLL_CAUSE_SABM_INFO_NOTALL;
} else {
switch (lctx->sapi) {
- case 0:
- /* SAPI0 must use contention resolution, i.e. L3 payload must exist */
- if (lctx->length == 0)
- return RLL_CAUSE_UFRM_INC_PARAM;
- break;
case 3:
/* SAPI3 doesn't support contention resolution */
if (lctx->length > 0)
return RLL_CAUSE_SABM_INFO_NOTALL;
break;
+ default:
+ break;
}
}
} else if (le->mode == LAPDM_MODE_MS) {