bluetooth: services: ras: Add RREQ implementation to RAS

Add implementation for Ranging Requestor, a Ranging Service
client which can be used to obtain channel sounding ranging
data from a Ranging Responder which operates as a Ranging
Service server.

This current implementation can perform most mandatory
features from the Ranging Profile/Ranging Service
specifications to alert an application of available ranging
data and receive the data from the server.

Further work can be done to add support for reading the
features from the server, receiving real time ranging data,
aborting receive operation, adding filters for ranging data.

Signed-off-by: Sean Madigan <[email protected]>

include/bluetooth/services/ras.h

@@ -11,6 +11,7 @@
 #include <zephyr/kernel.h>
 #include <zephyr/bluetooth/conn.h>
 #include <zephyr/bluetooth/uuid.h>
+#include <bluetooth/gatt_dm.h>
 
 /** @file
  *  @defgroup bt_ras Ranging Service API
@@ -130,6 +131,82 @@ struct ras_subevent_header {
 } __packed;
 BUILD_ASSERT(sizeof(struct ras_subevent_header) == BT_RAS_SUBEVENT_HEADER_LEN);
 
+/** @brief Ranging data ready callback. Called when peer has ranging data available.
+ *
+ * @param[in] conn            Connection Object.
+ * @param[in] ranging_counter Ranging counter ready to be requested.
+ */
+typedef void (*bt_ras_rreq_rd_ready_cb_t)(struct bt_conn *conn, uint16_t ranging_counter);
+
+/** @brief Ranging data overwritted callback. Called when peer has overwritten previously available
+ * ranging data.
+ *
+ * @param[in] conn            Connection Object.
+ * @param[in] ranging_counter Ranging counter which has been overwritten.
+ */
+typedef void (*bt_ras_rreq_rd_overwritten_cb_t)(struct bt_conn *conn, uint16_t ranging_counter);
+
+/** @brief Ranging data get complete callback. Called when ranging data get procedure has completed.
+ *
+ * @param[in] conn            Connection Object.
+ * @param[in] ranging_counter Ranging counter which has been overwritten.
+ * @param[in] err             Error code, 0 if the ranging data get was successful. Otherwise a
+ * negative error code.
+ */
+typedef void (*bt_ras_rreq_ranging_data_get_complete_t)(struct bt_conn *conn,
+							uint16_t ranging_counter, int err);
+
+/** @brief Allocate a RREQ context and assign GATT handles. Takes a reference to the connection.
+ *
+ * @param[in] dm   Discovery Object.
+ * @param[in] conn Connection Object.
+ *
+ * @retval 0 If the operation was successful.
+ *           Otherwise, a negative error code is returned.
+ */
+int bt_ras_rreq_alloc_and_assign_handles(struct bt_gatt_dm *dm, struct bt_conn *conn);
+
+/** @brief Get ranging data for given ranging counter.
+ *
+ * @note This should only be called after receiving a ranging data ready callback and
+ * when subscribed to ondemand ranging data and RAS-CP.
+ *
+ * @param[in] conn                 Connection Object.
+ * @param[in] ranging_data_out     Simple buffer to store received ranging data.
+ * @param[in] ranging_counter      Ranging counter to get.
+ * @param[in] data_get_complete_cb Callback called when get ranging data completes.
+ *
+ * @retval 0 If the operation was successful.
+ *           Otherwise, a negative error code is returned.
+ */
+int bt_ras_rreq_cp_get_ranging_data(struct bt_conn *conn, struct net_buf_simple *ranging_data_out,
+				    uint16_t ranging_counter,
+				    bt_ras_rreq_ranging_data_get_complete_t data_get_complete_cb);
+
+/** @brief Free RREQ context for connection. Should be called from disconnected callback. This will
+ * unsubscribe from any remaining subscriptions.
+ *
+ * @param[in] conn Connection Object.
+ */
+void bt_ras_rreq_free(struct bt_conn *conn);
+
+/** @brief Subscribe to all required on-demand ranging data subscriptions. Subscribes to ranging
+ * data ready, ranging data overwritten, on-demand ranging data and RAS-CP.
+ *
+ * @param[in] conn              Connection Object.
+ * @param[in] rd_ready_cb       Callback called when ranging data ready notification has been
+ * received.
+ * @param[in] rd_overwritten_cb Callback called when ranging data overwritten notification has been
+ * received, unless get ranging data has already been called for this ranging counter where
+ * data_get_complete_cb will be called instead.
+ *
+ * @retval 0 If the operation was successful.
+ *           Otherwise, a negative error code is returned.
+ */
+int bt_ras_rreq_on_demand_ranging_data_subscribe_all(
+	struct bt_conn *conn, bt_ras_rreq_rd_ready_cb_t rd_ready_cb,
+	bt_ras_rreq_rd_overwritten_cb_t rd_overwritten_cb);
+
 #ifdef __cplusplus
 }
 #endif

subsys/bluetooth/services/ras/CMakeLists.txt

@@ -5,3 +5,4 @@
 #
 
 add_subdirectory_ifdef(CONFIG_BT_RAS_RRSP rrsp)
+add_subdirectory_ifdef(CONFIG_BT_RAS_RREQ rreq)

subsys/bluetooth/services/ras/rreq/CMakeLists.txt

@@ -0,0 +1,9 @@
+#
+# Copyright (c) 2024 Nordic Semiconductor
+#
+# SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
+#
+
+zephyr_library_sources_ifdef(
+  CONFIG_BT_RAS_RREQ
+  ras_rreq.c)

subsys/bluetooth/services/ras/rreq/Kconfig.ras_rreq

@@ -10,11 +10,20 @@ menuconfig BT_RAS_RREQ
 	select EXPERIMENTAL
 	select BT_NRF_SERVICES
 	select BT_RAS
+	select BT_GATT_DM
+	select BT_GATT_CLIENT
 
 if BT_RAS_RREQ
 
 module = BT_RAS_RREQ
 module-str = RAS_RREQ
 source "${ZEPHYR_BASE}/subsys/logging/Kconfig.template.log_config"
 
+config BT_RAS_RREQ_MAX_ACTIVE_CONN
+	int "Number of simultaneously supported RREQ instances"
+	default BT_MAX_CONN
+	range 1 BT_MAX_CONN
+	help
+	  The number of simultaneous connections with an instance of RAS RREQ
+
 endif # BT_RAS_RREQ