bluetooth: host: Add support for CS set default settings

Added support for a new API for setting default channel
sounding settings, this is mainly a wrapper around the HCI
command.

For this add a new module for channel sounding, where new
channel sounding APIs will go.

Signed-off-by: Sean Madigan <sean.madigan@nordicsemi.no>

include/zephyr/bluetooth/cs.h

@@ -0,0 +1,86 @@
+/** @file
+ * @brief Bluetooth Channel Sounding handling
+ */
+
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#ifndef ZEPHYR_INCLUDE_BLUETOOTH_CS_H_
+#define ZEPHYR_INCLUDE_BLUETOOTH_CS_H_
+
+/**
+ * @brief Channel Sounding (CS)
+ * @defgroup bt_cs Channel Sounding (CS)
+ * @ingroup bluetooth
+ * @{
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include <zephyr/bluetooth/hci_types.h>
+#include <zephyr/bluetooth/conn.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum bt_cs_sync_antenna_selection_opt {
+ /** Use antenna identifier 1 for CS_SYNC packets. */
+ BT_CS_ANTENNA_SELECTION_OPT_ONE = BT_HCI_OP_LE_CS_ANTENNA_SEL_ONE,
+ /** Use antenna identifier 2 for CS_SYNC packets. */
+ BT_CS_ANTENNA_SELECTION_OPT_TWO = BT_HCI_OP_LE_CS_ANTENNA_SEL_TWO,
+ /** Use antenna identifier 3 for CS_SYNC packets. */
+ BT_CS_ANTENNA_SELECTION_OPT_THREE = BT_HCI_OP_LE_CS_ANTENNA_SEL_THREE,
+ /** Use antenna identifier 4 for CS_SYNC packets. */
+ BT_CS_ANTENNA_SELECTION_OPT_FOUR = BT_HCI_OP_LE_CS_ANTENNA_SEL_FOUR,
+ /** Use antennas in repetitive order from 1 to 4 for CS_SYNC packets. */
+ BT_CS_ANTENNA_SELECTION_OPT_REPETITIVE = BT_HCI_OP_LE_CS_ANTENNA_SEL_REP,
+ /** No recommendation for local controller antenna selection. */
+ BT_CS_ANTENNA_SELECTION_OPT_NO_RECOMMENDATION = BT_HCI_OP_LE_CS_ANTENNA_SEL_NONE,
+};
+
+/** Default CS settings in the local Controller */
+struct bt_cs_set_default_settings_param {
+ /** Enable CS initiator role. */
+ bool enable_initiator_role;
+ /** Enable CS reflector role. */
+ bool enable_reflector_role;
+ /** Antenna identifier to be used for CS_SYNC packets by the local controller.
+ */
+ enum bt_cs_sync_antenna_selection_opt cs_sync_antenna_selection;
+ /** Maximum output power (Effective Isotropic Radiated Power) to be used
+ * for all CS transmissions.
+ *
+ * Value range is @ref BT_HCI_OP_LE_CS_MIN_MAX_TX_POWER to
+ * @ref BT_HCI_OP_LE_CS_MAX_MAX_TX_POWER.
+ */
+ int8_t max_tx_power;
+};
+
+/** @brief Set Channel Sounding default settings.
+ *
+ * This command is used to set default Channel Sounding settings for this
+ * connection.
+ *
+ * @note To use this API @kconfig{CONFIG_BT_CHANNEL_SOUNDING} must be set.
+ *
+ * @param conn Connection Object.
+ * @param params Channel sounding default settings parameters.
+ *
+ * @return Zero on success or (negative) error code on failure.
+ */
+int bt_cs_set_default_settings(struct bt_conn *conn,
+ const struct bt_cs_set_default_settings_param *params);
+
+#ifdef __cplusplus
+}
+#endif
+
+/**
+ * @}
+ */
+
+#endif /* ZEPHYR_INCLUDE_BLUETOOTH_CS_H_ */

include/zephyr/bluetooth/hci_types.h

@@ -2395,6 +2395,28 @@ struct bt_hci_cp_le_tx_test_v4_tx_power {
  int8_t tx_power;
 } __packed;
 
+#define BT_HCI_OP_LE_CS_SET_DEFAULT_SETTINGS BT_OP(BT_OGF_LE, 0x008D) /* 0x208D */
+
+#define BT_HCI_OP_LE_CS_INITIATOR_ROLE_MASK BIT(0)
+#define BT_HCI_OP_LE_CS_REFLECTOR_ROLE_MASK BIT(1)
+
+#define BT_HCI_OP_LE_CS_MIN_MAX_TX_POWER -127
+#define BT_HCI_OP_LE_CS_MAX_MAX_TX_POWER 20
+
+#define BT_HCI_OP_LE_CS_ANTENNA_SEL_ONE 0x01
+#define BT_HCI_OP_LE_CS_ANTENNA_SEL_TWO 0x02
+#define BT_HCI_OP_LE_CS_ANTENNA_SEL_THREE 0x03
+#define BT_HCI_OP_LE_CS_ANTENNA_SEL_FOUR 0x04
+#define BT_HCI_OP_LE_CS_ANTENNA_SEL_REP 0xFE
+#define BT_HCI_OP_LE_CS_ANTENNA_SEL_NONE 0xFF
+
+struct bt_hci_cp_le_cs_set_default_settings {
+ uint16_t handle;
+ uint8_t role_enable;
+ uint8_t cs_sync_antenna_selection;
+ int8_t max_tx_power;
+} __packed;
+
 /* Event definitions */
 
 #define BT_HCI_EVT_UNKNOWN 0x00

subsys/bluetooth/host/CMakeLists.txt

@@ -68,6 +68,11 @@ if(CONFIG_BT_HCI_HOST)
  conn.c
  )
 
+ zephyr_library_sources_ifdef(
+ CONFIG_BT_CHANNEL_SOUNDING
+ cs.c
+ )
+
  if(CONFIG_BT_DF)
  zephyr_library_sources(
  direction.c

subsys/bluetooth/host/cs.c

@@ -0,0 +1,44 @@
+/* cs.c - Bluetooth Channel Sounding handling */
+
+/*
+ * Copyright (c) 2024 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/sys/byteorder.h>
+#include <zephyr/bluetooth/cs.h>
+#include <zephyr/bluetooth/hci.h>
+#include <zephyr/bluetooth/hci_types.h>
+
+#include "conn_internal.h"
+
+#if defined(CONFIG_BT_CHANNEL_SOUNDING)
+int bt_cs_set_default_settings(struct bt_conn *conn,
+ const struct bt_cs_set_default_settings_param *params)
+{
+ struct bt_hci_cp_le_cs_set_default_settings *cp;
+ struct net_buf *buf;
+
+ buf = bt_hci_cmd_create(BT_HCI_OP_LE_CS_SET_DEFAULT_SETTINGS, sizeof(*cp));
+ if (!buf) {
+ return -ENOBUFS;
+ }
+
+ cp = net_buf_add(buf, sizeof(*cp));
+ cp->handle = sys_cpu_to_le16(conn->handle);
+ cp->max_tx_power = params->max_tx_power;
+ cp->cs_sync_antenna_selection = params->cs_sync_antenna_selection;
+ cp->role_enable = 0;
+
+ if (params->enable_initiator_role) {
+ cp->role_enable |= BT_HCI_OP_LE_CS_INITIATOR_ROLE_MASK;
+ }
+
+ if (params->enable_reflector_role) {
+ cp->role_enable |= BT_HCI_OP_LE_CS_REFLECTOR_ROLE_MASK;
+ }
+
+ return bt_hci_cmd_send_sync(BT_HCI_OP_LE_CS_SET_DEFAULT_SETTINGS, buf, NULL);
+}
+#endif /* CONFIG_BT_CHANNEL_SOUNDING */