Bluetooth: Controller: Fix ISO Sync Receiver subevent jitter

Fix the jitter considered in the PDU reception in the
subevents of ISO Sync Receiver to not exceed such that the
reception is scheduled late (causing assertion).

Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>

Author: cvinayak

subsys/bluetooth/controller/ll_sw/nordic/lll/lll_sync_iso.c

@@ -1344,16 +1344,30 @@ static void isr_rx(void *param)
 		hcto -= radio_rx_chain_delay_get(lll->phy, PHY_FLAGS_S8);
 		hcto -= addr_us_get(lll->phy);
 		hcto -= radio_rx_ready_delay_get(lll->phy, PHY_FLAGS_S8);
+
 		overhead_us = radio_rx_chain_delay_get(lll->phy, PHY_FLAGS_S8);
 		overhead_us += addr_us_get(lll->phy);
 		overhead_us += radio_rx_ready_delay_get(lll->phy, PHY_FLAGS_S8);
 		overhead_us += (EVENT_CLOCK_JITTER_US << 1);
+
+		LL_ASSERT(EVENT_IFS_US > overhead_us);
+
 		jitter_max_us = (EVENT_IFS_US - overhead_us) >> 1;
-		jitter_max_us -= RANGE_DELAY_US + HAL_RADIO_TMR_START_DELAY_US;
+		jitter_max_us = (jitter_max_us * nse) / (lll->num_bis * lll->nse);
+		overhead_us = HAL_RADIO_TMR_START_DELAY_US;
+		if (jitter_max_us > overhead_us) {
+			jitter_max_us -= overhead_us;
+		} else {
+			jitter_max_us = 0U;
+		}
+
 		jitter_us = (EVENT_CLOCK_JITTER_US << 1) * nse;
 		if (jitter_us > jitter_max_us) {
 			jitter_us = jitter_max_us;
 		}
+
+		LL_ASSERT(hcto > jitter_us);
+
 		hcto -= jitter_us;
 
 		start_us = hcto;
@@ -1365,7 +1379,6 @@ static void isr_rx(void *param)
 		 * the current subevent we are listening.
 		 */
 		hcto += (jitter_us << 1);
-		hcto += RANGE_DELAY_US + HAL_RADIO_TMR_START_DELAY_US;
 	} else {
 		/* First subevent PDU was not received, hence setup radio packet
 		 * timer header complete timeout from where the first subevent