Bluetooth: host: Add IQ reports handing in DF connecte mode

Add reception of IQ sample report from controller.
Add applications notification about received reports.

Signed-off-by: Piotr Pryga <piotr.pryga@nordicsemi.no>

include/bluetooth/conn.h

@@ -23,6 +23,7 @@
 #include <bluetooth/hci_err.h>
 #include <bluetooth/addr.h>
 #include <bluetooth/gap.h>
+#include <bluetooth/direction.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -927,6 +928,17 @@ struct bt_conn_cb {
 				    struct bt_conn_le_data_len_info *info);
 #endif /* defined(CONFIG_BT_USER_DATA_LEN_UPDATE) */
 
+#if defined(CONFIG_BT_DF_CONNECTION_CTE_RX)
+	/** @brief Callback for IQ samples report collected when sampling
+	 *        CTE received by data channel PDU.
+	 *
+	 * @param conn      The connection object.
+	 * @param iq_report Report data for collected IQ samples.
+	 */
+	void (*cte_report_cb)(struct bt_conn *conn,
+			      const struct bt_df_conn_iq_samples_report *iq_report);
+#endif /* CONFIG_BT_DF_CONNECTION_CTE_RX */
+
 	struct bt_conn_cb *_next;
 };
 

include/bluetooth/direction.h

@@ -120,6 +120,28 @@ struct bt_df_conn_cte_rx_param {
 	const uint8_t *ant_ids;
 };
 
+struct bt_df_conn_iq_samples_report {
+	/** PHY that was used to receive PDU with CTE that was sampled. */
+	uint8_t rx_phy;
+	/** Channel index used to receive PDU with CTE that was sampled. */
+	uint8_t chan_idx;
+	/** The RSSI of the PDU with CTE (excluding CTE). */
+	int16_t rssi;
+	/** Id of antenna used to measure the RSSI. */
+	uint8_t rssi_ant_id;
+	/** Type of CTE (@ref bt_df_cte_type). */
+	uint8_t cte_type;
+	/** Duration of slots when received CTE type is AoA (@ref bt_df_antenna_switching_slot). */
+	uint8_t slot_durations;
+	/** Status of received PDU with CTE (@ref bt_df_packet_status). */
+	uint8_t packet_status;
+	/** Value of connection event counter when the CTE was received and sampled. */
+	uint16_t conn_evt_counter;
+	/** Number of IQ samples in report. */
+	uint8_t sample_count;
+	/** Pinter to IQ samples data. */
+	struct bt_hci_le_iq_sample const *sample;
+};
 /**
  * @brief Set or update the Constant Tone Extension parameters for periodic advertising set.
  *

subsys/bluetooth/host/conn.c

@@ -19,6 +19,7 @@
 
 #include <bluetooth/hci.h>
 #include <bluetooth/bluetooth.h>
+#include <bluetooth/direction.h>
 #include <bluetooth/conn.h>
 #include <drivers/bluetooth/hci_driver.h>
 #include <bluetooth/att.h>
@@ -38,6 +39,7 @@
 #include "att_internal.h"
 #include "gatt_internal.h"
 #include "iso_internal.h"
+#include "direction_internal.h"
 
 struct tx_meta {
 	struct bt_conn_tx *tx;
@@ -2921,4 +2923,33 @@ int bt_conn_init(void)
 	return 0;
 }
 
+#if defined(CONFIG_BT_DF_CONNECTION_CTE_RX)
+void bt_hci_le_df_connection_iq_report(struct net_buf *buf)
+{
+	struct bt_df_conn_iq_samples_report iq_report;
+	struct bt_conn *conn;
+	struct bt_conn_cb *cb;
+	int err;
+
+	err = hci_df_prepare_connection_iq_report(buf, &iq_report, &conn);
+	if (err) {
+		BT_ERR("Prepare CTE conn IQ report failed %d", err);
+		return;
+	}
+
+	for (cb = callback_list; cb; cb = cb->_next) {
+		if (cb->cte_report_cb) {
+			cb->cte_report_cb(conn, &iq_report);
+		}
+	}
+
+	STRUCT_SECTION_FOREACH(bt_conn_cb, cb)
+	{
+		if (cb->cte_report_cb) {
+			cb->cte_report_cb(conn, &iq_report);
+		}
+	}
+}
+#endif /* CONFIG_BT_DF_CONNECTION_CTE_RX */
+
 #endif /* CONFIG_BT_CONN */

subsys/bluetooth/host/direction.c

@@ -542,6 +542,55 @@ static int hci_df_set_conn_cte_rx_enable(struct bt_conn *conn, bool enable,
 
 	return err;
 }
+
+int hci_df_prepare_connection_iq_report(struct net_buf *buf,
+					 struct bt_df_conn_iq_samples_report *report,
+					 struct bt_conn **conn_to_report)
+{
+	struct bt_hci_evt_le_connection_iq_report *evt;
+	struct bt_conn *conn;
+
+	if (buf->len < sizeof(*evt)) {
+		BT_ERR("Unexpected end of buffer");
+		return -EINVAL;
+	}
+
+	evt = net_buf_pull_mem(buf, sizeof(*evt));
+
+	conn = bt_conn_lookup_handle(sys_le16_to_cpu(evt->conn_handle));
+
+	if (!conn) {
+		BT_ERR("Unknown conn handle 0x%04X for iq samples report",
+		       sys_le16_to_cpu(evt->conn_handle));
+		return -EINVAL;
+	}
+
+	if (!atomic_test_bit(conn->flags, BT_CONN_CTE_RX_ENABLED)) {
+		BT_ERR("Received conn CTE report when CTE receive disabled");
+		return -EINVAL;
+	}
+
+	if (!(conn->cte_type & BIT(evt->cte_type))) {
+		BT_DBG("CTE filtered out by cte_type: %u", evt->cte_type);
+		return -EINVAL;
+	}
+
+	report->chan_idx = evt->data_chan_idx;
+	report->rx_phy = evt->rx_phy;
+	report->chan_idx = evt->data_chan_idx;
+	report->rssi = evt->rssi;
+	report->rssi_ant_id = evt->rssi_ant_id;
+	report->cte_type = BIT(evt->cte_type);
+	report->packet_status = evt->packet_status;
+	report->slot_durations = evt->slot_durations;
+	report->conn_evt_counter = sys_le16_to_cpu(evt->conn_evt_counter);
+	report->sample_count = evt->sample_count;
+	report->sample = evt->sample;
+
+	*conn_to_report = conn;
+
+	return 0;
+}
 #endif /* CONFIG_BT_DF_CONNECTION_CTE_RX */
 
 /* @brief Function initializes Direction Finding in Host

subsys/bluetooth/host/direction_internal.h

@@ -10,3 +10,6 @@ int le_df_init(void);
 void hci_df_prepare_connectionless_iq_report(struct net_buf *buf,
 					     struct bt_df_per_adv_sync_iq_samples_report *report,
 					     struct bt_le_per_adv_sync **per_adv_sync_to_report);
+int hci_df_prepare_connection_iq_report(struct net_buf *buf,
+					struct bt_df_conn_iq_samples_report *report,
+					struct bt_conn **conn_to_report);

subsys/bluetooth/host/hci_core.c

@@ -2225,6 +2225,10 @@ static const struct event_handler meta_events[] = {
 	EVENT_HANDLER(BT_HCI_EVT_LE_CONNECTIONLESS_IQ_REPORT, bt_hci_le_df_connectionless_iq_report,
 		      sizeof(struct bt_hci_evt_le_connectionless_iq_report)),
 #endif /* CONFIG_BT_DF_CONNECTIONLESS_CTE_RX */
+#if defined(CONFIG_BT_DF_CONNECTION_CTE_RX)
+	EVENT_HANDLER(BT_HCI_EVT_LE_CONNECTION_IQ_REPORT, bt_hci_le_df_connection_iq_report,
+		      sizeof(struct bt_hci_evt_le_connection_iq_report)),
+#endif /* CONFIG_BT_DF_CONNECTION_CTE_RX */
 };
 
 static void hci_le_meta_event(struct net_buf *buf)

subsys/bluetooth/host/hci_core.h

@@ -450,3 +450,5 @@ void bt_hci_read_remote_features_complete(struct net_buf *buf);
 void bt_hci_read_remote_ext_features_complete(struct net_buf *buf);
 void bt_hci_role_change(struct net_buf *buf);
 void bt_hci_synchronous_conn_complete(struct net_buf *buf);
+
+void bt_hci_le_df_connection_iq_report(struct net_buf *buf);