samples: Bluetooth: Fix BAP unicast client and server buffer counts

Fix BAP unicast and server sample ISO Tx buffer count to
match the minimum required to consistently transmit SDUs
in every ISO interval.

Signed-off-by: Vinayak Kariappa Chettimada <[email protected]>

Author: cvinayak

samples/bluetooth/bap_unicast_client/overlay-bt_ll_sw_split.conf

@@ -1,17 +1,23 @@
+# Zephyr Bluetooth Controller needs 3 Tx Buffers enqueued as the Number of Completed Packets event
+# is returned one ISO interval later, i.e. the PDU flush is checked at the prepare of radio events.
+CONFIG_BT_ISO_TX_BUF_COUNT=6
+
+# Zephyr Bluetooth Controller
 CONFIG_BT_LL_SW_SPLIT=y
-CONFIG_BT_CTLR_SCAN_DATA_LEN_MAX=1650
-CONFIG_BT_CTLR_ISO_TX_BUFFERS=4
+
+# Supports the highest advertising data that is set in a single HCI command in
+# Zephyr Bluetooth Controller
+CONFIG_BT_CTLR_SCAN_DATA_LEN_MAX=191
+
+# Number of supported streams
 CONFIG_BT_CTLR_ISOAL_SOURCES=2
 CONFIG_BT_CTLR_ISOAL_SINKS=1
 
+# Numbe of ISO Tx Buffers
+CONFIG_BT_CTLR_ISO_TX_BUFFERS=6
+
 # Support the highest SDU size required by any BAP LC3 presets (155) + 8 bytes of HCI ISO Data
 # packet overhead (the Packet_Sequence_Number, ISO_SDU_Length, Packet_Status_Flag fields; and
 # the optional Time_Stamp field, if supplied)
 CONFIG_BT_CTLR_ISO_TX_BUFFER_SIZE=163
 CONFIG_BT_CTLR_ISO_TX_SDU_LEN_MAX=155
-
-CONFIG_BT_CTLR_ADVANCED_FEATURES=y
-CONFIG_BT_CTLR_CONN_ISO_LOW_LATENCY_POLICY=y
-
-# Use the below if the sample is sending stale packet sequence number
-# CONFIG_BT_CTLR_ISOAL_SN_STRICT=n

samples/bluetooth/bap_unicast_server/overlay-bt_ll_sw_split.conf

@@ -1,15 +1,22 @@
+# Zephyr Bluetooth Controller needs 3 Tx Buffers enqueued as the Number of Completed Packets event
+# is returned one ISO interval later, i.e. the PDU flush is checked at the prepare of radio events.
+CONFIG_BT_ISO_TX_BUF_COUNT=3
+
+# Zephyr Bluetooth Controller
 CONFIG_BT_LL_SW_SPLIT=y
+
+# Zephyr Controller tested maximum advertising data that can be set in a single HCI command
 CONFIG_BT_CTLR_ADV_DATA_LEN_MAX=191
-CONFIG_BT_CTLR_ISO_TX_BUFFERS=2
+
+# Number of supported streams
 CONFIG_BT_CTLR_ISOAL_SOURCES=1
 CONFIG_BT_CTLR_ISOAL_SINKS=2
 
+# Numbe of ISO Tx Buffers
+CONFIG_BT_CTLR_ISO_TX_BUFFERS=3
+
 # Support the highest SDU size required by any BAP LC3 presets (155) + 8 bytes of HCI ISO Data
 # packet overhead (the Packet_Sequence_Number, ISO_SDU_Length, Packet_Status_Flag fields; and
 # the optional Time_Stamp field, if supplied)
 CONFIG_BT_CTLR_ISO_TX_BUFFER_SIZE=163
 CONFIG_BT_CTLR_ISO_TX_SDU_LEN_MAX=155
-
-# Use the below if the sample is sending stale packet sequence number
-# CONFIG_BT_CTLR_ADVANCED_FEATURES=y
-# CONFIG_BT_CTLR_ISOAL_SN_STRICT=n