trx_toolkit/burst_fwd.py: properly pass-filter multiple time-slots

Previously it was only possible to configure a single time-slot
that would be pass-filtered by a BurstForwarder instance. In some
applications it would be useful to configure multiple time-slots,
so let's refactor the time-slot pass-filtering algorithm.

Change-Id: Ie1490adaf7a7c62c966aeb60c1898eaf3b5a1e84

src/target/trx_toolkit/burst_fwd.py

@@ -43,11 +43,10 @@ class BurstForwarder:
 	    and transmit frequencies. It would be great to distinguish
 	    between RX and TX frequencies for both BTS and MS.
 
-	  - ts_pass - currently active timeslot, configured by the MS.
+	  - ts_pass_list - the list of active (i.e. configured)
-	    It can be activated or deactivated using SETSLOT control
+	    timeslot numbers for the MS. A timeslot can be activated
-	    command from the MS.
+	    or deactivated using SETSLOT control command from the MS.
 
-	    FIXME: only a single timeslot can be activated!
 	    FIXME: there is no such list for the BTS side.
 
 	== Preprocessing and measurement simulation
@@ -152,7 +151,7 @@ class BurstForwarder:
 		self.burst_ul_drop_period = 1
 
 		# Init timeslot filter (drop everything by default)
-		self.ts_pass = None
+		self.ts_pass_list = []
 
 		# Reset Timing Advance value
 		self.ta = 0
@@ -288,7 +287,7 @@ class BurstForwarder:
 			return None
 
 		# Timeslot filter
-		if msg.tn != self.ts_pass:
+		if msg.tn not in self.ts_pass_list:
 			return None
 
 		# Path loss simulation

src/target/trx_toolkit/ctrl_if_bb.py

@@ -109,9 +109,21 @@ class CTRLInterfaceBB(CTRLInterface):
 			# TS activation / deactivation
 			# We don't care about ts_type
 			if ts_type == 0:
-				self.burst_fwd.ts_pass = None
+				# Deactivate TS (remove from TS pass-filter list)
+				if ts in self.burst_fwd.ts_pass_list:
+					self.burst_fwd.ts_pass_list.remove(ts)
+				else:
+					print("[!] TS %u was not activated before" % ts)
+					# TODO: uncomment as soon as RESET is introduced
+					# return -1
 			else:
-				self.burst_fwd.ts_pass = ts
+				# Activate TS (add to TS pass-filter list)
+				if ts not in self.burst_fwd.ts_pass_list:
+					self.burst_fwd.ts_pass_list.append(ts)
+				else:
+					print("[!] TS %u was already activated before" % ts)
+					# TODO: uncomment as soon as RESET is introduced
+					# return -1
 
 			return 0