Bluetooth: controller: Add/Remove ACAD on create/terminate BIG

Added implementation to add/remove ACAD field in the common
extended header format of the periodic advertising PDU on
create/terminate BIG.

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

Author: cvinayak

subsys/bluetooth/controller/ll_sw/ull_adv_internal.h

@@ -187,6 +187,10 @@ void ull_adv_sync_update(struct ll_adv_sync_set *sync, uint32_t slot_plus_us,
 /* helper function to schedule a mayfly to get sync offset */
 void ull_adv_sync_offset_get(struct ll_adv_set *adv);
 
+/* helper function to reserve ACAD field in PDU buffer */
+uint8_t ull_adv_sync_acad_enable(struct lll_adv_sync *lll_sync,
+				 uint8_t acad_len, void **acad);
+
 int ull_adv_iso_init(void);
 int ull_adv_iso_reset(void);
 

subsys/bluetooth/controller/ll_sw/ull_adv_iso.c

@@ -63,6 +63,8 @@ uint8_t ll_big_create(uint8_t big_handle, uint8_t adv_handle, uint8_t num_bis,
 	struct node_rx_pdu *node_rx;
 	struct ll_adv_iso *adv_iso;
 	struct ll_adv_set *adv;
+	uint8_t *acad;
+	uint8_t err;
 
 	adv_iso = ull_adv_iso_get(big_handle);
 
@@ -130,6 +132,17 @@ uint8_t ll_big_create(uint8_t big_handle, uint8_t adv_handle, uint8_t num_bis,
 	if (num_bis != 1) {
 		return BT_HCI_ERR_MEM_CAPACITY_EXCEEDED;
 	}
+
+	/* Add ACAD to AUX_SYNC_IND */
+	err = ull_adv_sync_acad_enable(lll_adv_sync,
+				       (sizeof(struct pdu_big_info) + 2),
+				       (void **)&acad);
+	if (err) {
+		return err;
+	}
+	acad[0] = sizeof(struct pdu_big_info) + 1;
+	acad[1] = BT_DATA_BIG_INFO;
+
 	/* TODO: For now we can just use the unique BIG handle as the BIS
 	 * handle until we support multiple BIS
 	 */
@@ -146,8 +159,6 @@ uint8_t ll_big_create(uint8_t big_handle, uint8_t adv_handle, uint8_t num_bis,
 	adv_iso->encryption = encryption;
 	memcpy(adv_iso->bcode, bcode, sizeof(adv_iso->bcode));
 
-	/* TODO: Add ACAD to AUX_SYNC_IND */
-
 	/* TODO: start sending BIS empty data packet for each BIS */
 	ull_adv_iso_start(adv_iso, 0 /* TODO: Calc ticks_anchor */);
 
@@ -204,6 +215,7 @@ uint8_t ll_big_terminate(uint8_t big_handle, uint8_t reason)
 	struct ll_adv_iso *adv_iso;
 	struct lll_adv *lll_adv;
 	uint32_t ret;
+	uint8_t err;
 
 	adv_iso = ull_adv_iso_get(big_handle);
 	if (!adv_iso) {
@@ -218,6 +230,12 @@ uint8_t ll_big_terminate(uint8_t big_handle, uint8_t reason)
 
 	lll_adv_sync = lll_adv->sync;
 
+	/* Remove ACAD to AUX_SYNC_IND */
+	err = ull_adv_sync_acad_enable(lll_adv_sync, 0, NULL);
+	if (err) {
+		return err;
+	}
+
 	/* TODO: Terminate all BIS data paths */
 
 	ret = ticker_stop(TICKER_INSTANCE_ID_CTLR, TICKER_USER_ID_ULL_HIGH,

subsys/bluetooth/controller/ll_sw/ull_adv_sync.c

@@ -790,6 +790,151 @@ uint8_t ull_adv_sync_pdu_alloc(struct ll_adv_set *adv,
 	return 0;
 }
 
+uint8_t ull_adv_sync_acad_enable(struct lll_adv_sync *lll_sync,
+				 uint8_t acad_len, void **acad)
+{
+	struct pdu_adv_com_ext_adv *ter_com_hdr, *ter_com_hdr_prev;
+	struct pdu_adv_ext_hdr *ter_hdr, ter_hdr_prev;
+	struct pdu_adv *ter_pdu, *ter_pdu_prev;
+	uint8_t *ter_dptr, *ter_dptr_prev;
+	uint16_t ter_len, ter_len_prev;
+	uint8_t acad_len_prev;
+	uint8_t *ad_data;
+	uint8_t ter_idx;
+	uint8_t ad_len;
+
+	/* Get reference to previous tertiary PDU data */
+	ter_pdu_prev = lll_adv_sync_data_peek(lll_sync, NULL);
+	ter_com_hdr_prev = (void *)&ter_pdu_prev->adv_ext_ind;
+	ter_hdr = (void *)ter_com_hdr_prev->ext_hdr_adv_data;
+	ter_hdr_prev = *ter_hdr;
+	ter_dptr_prev = ter_hdr->data;
+
+	/* Get reference to new tertiary PDU data buffer */
+	ter_pdu = lll_adv_sync_data_alloc(lll_sync, NULL, &ter_idx);
+	ter_pdu->type = ter_pdu_prev->type;
+	ter_pdu->rfu = 0U;
+	ter_pdu->chan_sel = 0U;
+	ter_com_hdr = (void *)&ter_pdu->adv_ext_ind;
+	ter_com_hdr->adv_mode = ter_com_hdr_prev->adv_mode;
+	ter_hdr = (void *)ter_com_hdr->ext_hdr_adv_data;
+	ter_dptr = ter_hdr->data;
+	*(uint8_t *)ter_hdr = 0U;
+
+	/* No AdvA */
+	/* No TargetA */
+
+	/* TODO: CTEInfo */
+
+	/* No ADI */
+
+	/* AuxPtr */
+	if (ter_hdr_prev.aux_ptr) {
+		ter_dptr_prev += sizeof(struct pdu_adv_aux_ptr);
+
+		ter_hdr->aux_ptr = 1;
+		ter_dptr += sizeof(struct pdu_adv_aux_ptr);
+	}
+
+	/* No SyncInfo */
+
+	/* Tx Power flag */
+	if (ter_hdr_prev.tx_pwr) {
+		ter_dptr_prev++;
+
+		ter_hdr->tx_pwr = 1;
+		ter_dptr++;
+	}
+
+	/* Calc previous ACAD len and update PDU len */
+	ter_len_prev = ter_dptr_prev - (uint8_t *)ter_com_hdr_prev;
+	if (ter_len_prev < (ter_com_hdr_prev->ext_hdr_len +
+			    offsetof(struct pdu_adv_com_ext_adv,
+				     ext_hdr_adv_data))) {
+		acad_len_prev = ter_com_hdr_prev->ext_hdr_len +
+				offsetof(struct pdu_adv_com_ext_adv,
+					 ext_hdr_adv_data) - ter_len_prev;
+		ter_len_prev += acad_len_prev;
+		ter_dptr_prev += acad_len_prev;
+	} else {
+		acad_len_prev = 0;
+		ter_len_prev = offsetof(struct pdu_adv_com_ext_adv,
+					ext_hdr_adv_data);
+		ter_dptr_prev = (uint8_t *)ter_com_hdr_prev + ter_len_prev;
+	}
+
+	/* Did we parse beyond PDU length? */
+	if (ter_len_prev > ter_pdu_prev->len) {
+		/* we should not encounter invalid length */
+		return BT_HCI_ERR_UNSPECIFIED;
+	}
+
+	/* Fill new ACAD */
+	if (acad) {
+		*acad = ter_dptr;
+		ter_dptr += acad_len;
+	}
+
+	/* Calc current tertiary PDU len */
+	ter_len = ull_adv_aux_hdr_len_calc(ter_com_hdr, &ter_dptr);
+	ull_adv_aux_hdr_len_fill(ter_com_hdr, ter_len);
+
+	/* Calc the previous AD data length in auxiliary PDU */
+	ad_len = ter_pdu_prev->len - ter_len_prev;
+	ad_data = ter_dptr_prev;
+
+	/* Add AD len to tertiary PDU length */
+	ter_len += ad_len;
+
+	/* Check AdvData overflow */
+	if (ter_len > PDU_AC_PAYLOAD_SIZE_MAX) {
+		return BT_HCI_ERR_PACKET_TOO_LONG;
+	}
+
+	/* set the tertiary PDU len */
+	ter_pdu->len = ter_len;
+
+	/* Start filling tertiary PDU payload based on flags from here
+	 * ==============================================================
+	 */
+
+	/* Fill AdvData in tertiary PDU */
+	memmove(ter_dptr, ad_data, ad_len);
+
+	/* NOTE: ACAD in tertiary PDU is filled by the caller of this
+	 *       function. Only decrement the new ACAD length.
+	 */
+	ter_dptr_prev -= acad_len_prev;
+	if (acad) {
+		ter_dptr -= acad_len;
+	}
+
+	/* Tx Power */
+	if (ter_hdr->tx_pwr) {
+		*--ter_dptr = *--ter_dptr_prev;
+	}
+
+	/* No SyncInfo in tertiary PDU */
+
+	/* AuxPtr */
+	if (ter_hdr_prev.aux_ptr) {
+		ter_dptr_prev -= sizeof(struct pdu_adv_aux_ptr);
+
+		ull_adv_aux_ptr_fill(&ter_dptr, lll_sync->adv->phy_s);
+	}
+
+	/* No ADI */
+
+	/* TODO: CTEInfo */
+
+	/* No TargetA*/
+	/* No AdvA */
+
+	lll_adv_sync_data_enqueue(lll_sync, ter_idx);
+
+	return 0;
+}
+
 /* @brief Set or clear fields in extended advertising header and store
  *        extra_data if requested.
  *