Bluetooth: CCP: Initial CCP Client implemenation

Added initial CCP client implementation that simply
does discovery of TBS on a remote CCP server.

Signed-off-by: Emil Gydesen <emil.gydesen@nordicsemi.no>

doc/connectivity/bluetooth/api/audio/bluetooth-le-audio-arch.rst

@@ -726,8 +726,8 @@ Bluetooth Audio Stack.
    |        |                               |         |                  | - Shell Module        | - Sample Application (in progress)               |
    |        |                               |         |                  | - BSIM test           |                                                  |
    |        +-------------------------------+---------+------------------+-----------------------+--------------------------------------------------+
-   |        | Call Control Client           | 1.0     | 3.0              | - Feature complete    | - API refactor                                   |
-   |        |                               |         |                  | - Shell Module        | - Sample Application                             |
+   |        | Call Control Client           | 1.0     | 3.0              | - Feature complete    | - API refactor (in progress)                     |
+   |        |                               |         |                  | - Shell Module        | - Sample Application (in progress)               |
    |        |                               |         |                  | - BSIM test           |                                                  |
    +--------+-------------------------------+---------+------------------+-----------------------+--------------------------------------------------+
    | MCP    | Media Control Server          | 1.0     | 3.0              | - Feature complete    | - API refactor                                   |

doc/connectivity/bluetooth/shell/audio/ccp.rst

@@ -33,3 +33,28 @@ Setup
    Registered GTBS bearer
    Registered bearer[1]
    uart:~$ bt connect xx:xx:xx:xx:xx:xx public
+
+Call Control Client
+*******************
+The Call Control Client is a role that typically resides on resource contrained devices such as
+earbuds or headsets.
+
+Using the Call Control Client
+=============================
+The Client can control a remote CCP server device.
+For example a remote device may have an incoming call that can be accepted by the Client.
+
+.. code-block:: console
+
+   uart:~$ ccp_call_control_client --help
+   ccp_call_control_client - Bluetooth CCP Call Control Client shell commands
+   Subcommands:
+     discover  : Discover GTBS and TBS on remote device
+
+Example Usage when connected
+============================
+
+.. code-block:: console
+
+   uart:~$ ccp_call_control_client discover
+   Discovery completed with GTBS and 1 TBS bearers

include/zephyr/bluetooth/audio/ccp.h

@@ -31,8 +31,12 @@
  * The profile is not limited to carrier phone calls and can be used with common applications like
  * Discord and Teams.
  */
+#include <stdint.h>
 
+#include <zephyr/autoconf.h>
 #include <zephyr/bluetooth/audio/tbs.h>
+#include <zephyr/bluetooth/conn.h>
+#include <zephyr/sys/slist.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -90,6 +94,82 @@ int bt_ccp_call_control_server_unregister_bearer(struct bt_ccp_call_control_serv
 
 /** @} */ /* End of group bt_ccp_call_control_server */
 
+/**
+ * @defgroup bt_ccp_call_control_client CCP Call Control Client APIs
+ * @ingroup bt_ccp
+ * @{
+ */
+/** Abstract Call Control Client structure. */
+struct bt_ccp_call_control_client;
+
+/** Abstract Call Control Client bearer structure. */
+struct bt_ccp_call_control_client_bearer;
+
+/** Struct with information about bearers of a client */
+struct bt_ccp_call_control_client_bearers {
+#if defined(CONFIG_BT_TBS_CLIENT_GTBS)
+	/** The GTBS bearer. */
+	struct bt_ccp_call_control_client_bearer *gtbs_bearer;
+#endif /* CONFIG_BT_TBS_CLIENT_GTBS */
+
+#if defined(CONFIG_BT_TBS_CLIENT_TBS)
+	/** Number of TBS bearers in @p tbs_bearers */
+	size_t tbs_count;
+
+	/** Array of pointers of TBS bearers */
+	struct bt_ccp_call_control_client_bearer
+		*tbs_bearers[CONFIG_BT_CCP_CALL_CONTROL_CLIENT_BEARER_COUNT];
+#endif /* CONFIG_BT_TBS_CLIENT_TBS */
+};
+
+/**
+ * @brief Struct to hold the Telephone Bearer Service client callbacks
+ *
+ * These can be registered for usage with bt_tbs_client_register_cb().
+ */
+struct bt_ccp_call_control_client_cb {
+	/**
+	 * @brief Callback function for bt_ccp_call_control_client_discover().
+	 *
+	 * This callback is called once the discovery procedure is completed.
+	 *
+	 * @param client       Call Control Client pointer.
+	 * @param err          Error value. 0 on success, GATT error on positive
+	 *                     value or errno on negative value.
+	 * @param bearers      The bearers found.
+	 */
+	void (*discover)(struct bt_ccp_call_control_client *client, int err,
+			 struct bt_ccp_call_control_client_bearers *bearers);
+
+	/** @internal Internally used field for list handling */
+	sys_snode_t _node;
+};
+
+int bt_ccp_call_control_client_discover(struct bt_conn *conn,
+					struct bt_ccp_call_control_client **out_client);
+
+/**
+ * @brief Register callbacks for the Call Control Client
+ *
+ * @param cb The callback struct
+ *
+ * @retval 0 Succsss
+ * @retval -EINVAL @p cb is NULL
+ * @retval -EEXISTS @p cb is already registered
+ */
+int bt_ccp_call_control_client_register_cb(struct bt_ccp_call_control_client_cb *cb);
+
+/**
+ * @brief Unregister callbacks for the Call Control Client
+ *
+ * @param cb The callback struct
+ *
+ * @retval 0 Succsss
+ * @retval -EINVAL @p cb is NULL
+ * @retval -EALREADY @p cb is not registered
+ */
+int bt_ccp_call_control_client_unregister_cb(struct bt_ccp_call_control_client_cb *cb);
+/** @} */ /* End of group bt_ccp_call_control_client */
 #ifdef __cplusplus
 }
 #endif

samples/bluetooth/ccp_call_control_client/CMakeLists.txt

@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(ccp_call_control_client)
+
+target_sources(app PRIVATE
+  src/main.c
+)
+
+zephyr_library_include_directories(${ZEPHYR_BASE}/samples/bluetooth)

samples/bluetooth/ccp_call_control_client/Kconfig.sysbuild

@@ -0,0 +1,15 @@
+# Copyright 2023 Nordic Semiconductor ASA
+# SPDX-License-Identifier: Apache-2.0
+
+source "share/sysbuild/Kconfig"
+
+config NET_CORE_BOARD
+	string
+	default "nrf5340dk/nrf5340/cpunet" if "$(BOARD)" = "nrf5340dk"
+	default "nrf5340_audio_dk/nrf5340/cpunet" if "$(BOARD)" = "nrf5340_audio_dk"
+	default "nrf5340bsim/nrf5340/cpunet" if $(BOARD_TARGET_STRING) = "NRF5340BSIM_NRF5340_CPUAPP"
+
+config NET_CORE_IMAGE_HCI_IPC
+	bool "HCI IPC image on network core"
+	default y
+	depends on NET_CORE_BOARD != ""

samples/bluetooth/ccp_call_control_client/README.rst

@@ -0,0 +1,78 @@
+.. zephyr:code-sample:: bluetooth_ccp_call_control_client
+   :name: Call Control Profile (CCP) Call Control Server
+   :relevant-api: bluetooth bt_ccp bt_tbs
+
+   CCP Call Control Server sample that registers one or more TBS bearers and advertises the
+   TBS UUID(s).
+
+Overview
+********
+
+Application demonstrating the CCP Call Control Client functionality.
+Starts by scanning for a CCP Call Control Server to connect and set up calls.
+
+The profile works for both GAP Central and GAP Peripheral devices, but this sample only assumes the
+GAP Central role.
+
+This sample can be found under :zephyr_file:`samples/bluetooth/ccp_call_control_client`
+in the Zephyr tree.
+
+Check the :zephyr:code-sample-category:`bluetooth` samples for general information.
+
+Requirements
+************
+
+* BlueZ running on the host, or
+* A board with Bluetooth Low Energy 5.2 support
+
+Building and Running
+********************
+
+When building targeting an nrf52 series board with the Zephyr Bluetooth Controller,
+use ``-DOVERLAY_CONFIG=overlay-bt_ll_sw_split.conf`` to enable the required feature support.
+
+Building for an nrf5340dk
+-------------------------
+
+You can build both the application core image and an appropriate controller image for the network
+core with:
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/bluetooth/ccp_call_control_client/
+   :board: nrf5340dk/nrf5340/cpuapp
+   :goals: build
+   :west-args: --sysbuild
+
+If you prefer to only build the application core image, you can do so by doing instead:
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/bluetooth/ccp_call_control_client/
+   :board: nrf5340dk/nrf5340/cpuapp
+   :goals: build
+
+In that case you can pair this application core image with the
+:zephyr:code-sample:`bluetooth_hci_ipc` sample
+:zephyr_file:`samples/bluetooth/hci_ipc/nrf5340_cpunet_iso-bt_ll_sw_split.conf` configuration.
+
+Building for a simulated nrf5340bsim
+------------------------------------
+
+Similarly to how you would for real HW, you can do:
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/bluetooth/ccp_call_control_client/
+   :board: nrf5340bsim/nrf5340/cpuapp
+   :goals: build
+   :west-args: --sysbuild
+
+Note this will produce a Linux executable in :file:`./build/zephyr/zephyr.exe`.
+For more information, check :ref:`this board documentation <nrf5340bsim>`.
+
+Building for a simulated nrf52_bsim
+-----------------------------------
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/bluetooth/ccp_call_control_client/
+   :board: nrf52_bsim
+   :goals: build
+   :gen-args: -DOVERLAY_CONFIG=overlay-bt_ll_sw_split.conf

samples/bluetooth/ccp_call_control_client/boards/nrf5340_audio_dk_nrf5340_cpuapp.conf

@@ -0,0 +1,6 @@
+CONFIG_BT_BUF_EVT_RX_SIZE=255
+CONFIG_BT_BUF_ACL_RX_SIZE=255
+CONFIG_BT_BUF_ACL_TX_SIZE=251
+CONFIG_BT_BUF_CMD_TX_SIZE=255
+
+CONFIG_BT_SEND_ECC_EMULATION=y

samples/bluetooth/ccp_call_control_client/boards/nrf5340dk_nrf5340_cpuapp.conf

@@ -0,0 +1,6 @@
+CONFIG_BT_BUF_EVT_RX_SIZE=255
+CONFIG_BT_BUF_ACL_RX_SIZE=255
+CONFIG_BT_BUF_ACL_TX_SIZE=251
+CONFIG_BT_BUF_CMD_TX_SIZE=255
+
+CONFIG_BT_SEND_ECC_EMULATION=y

samples/bluetooth/ccp_call_control_client/overlay-bt_ll_sw_split.conf

@@ -0,0 +1,6 @@
+# Zephyr Bluetooth Controller
+CONFIG_BT_LL_SW_SPLIT=y
+
+# Zephyr Controller tested maximum advertising data that can be set in a single HCI command
+CONFIG_BT_CTLR_ADV_DATA_LEN_MAX=191
+CONFIG_BT_CTLR_SCAN_DATA_LEN_MAX=191

samples/bluetooth/ccp_call_control_client/prj.conf

@@ -0,0 +1,22 @@
+CONFIG_BT=y
+CONFIG_LOG=y
+CONFIG_BT_CENTRAL=y
+CONFIG_BT_GATT_CLIENT=y
+CONFIG_BT_GATT_AUTO_DISCOVER_CCC=y
+CONFIG_BT_AUDIO=y
+CONFIG_BT_EXT_ADV=y
+CONFIG_BT_DEVICE_NAME="CCP Call Control Client"
+
+CONFIG_BT_SMP=y
+CONFIG_BT_KEYS_OVERWRITE_OLDEST=y
+
+# CCP support
+CONFIG_BT_CCP_CALL_CONTROL_CLIENT=y
+CONFIG_BT_CCP_CALL_CONTROL_CLIENT_BEARER_COUNT=2
+CONFIG_BT_TBS_CLIENT_GTBS=y
+CONFIG_BT_TBS_CLIENT_TBS=y
+CONFIG_BT_TBS_CLIENT_MAX_TBS_INSTANCES=1
+CONFIG_UTF8=y
+
+# TBS Client may require up to 12 buffers
+CONFIG_BT_ATT_TX_COUNT=12

samples/bluetooth/ccp_call_control_client/sample.yaml

@@ -0,0 +1,30 @@
+sample:
+  description: Bluetooth Low Energy Call Control Profile Server sample
+  name: Bluetooth Low Energy Call Control Profile Server sample
+tests:
+  sample.bluetooth.ccp_call_control_client:
+    harness: bluetooth
+    platform_allow:
+      - qemu_cortex_m3
+      - qemu_x86
+      - nrf5340dk/nrf5340/cpuapp
+      - nrf5340bsim/nrf5340/cpuapp
+    integration_platforms:
+      - qemu_x86
+      - nrf5340dk/nrf5340/cpuapp
+    tags: bluetooth
+    sysbuild: true
+  sample.bluetooth.ccp_call_control_client.bt_ll_sw_split:
+    harness: bluetooth
+    platform_allow:
+      - nrf52_bsim
+      - nrf52833dk/nrf52833
+      - nrf52840dk/nrf52840
+      - nrf52840dongle/nrf52840
+    integration_platforms:
+      - nrf52_bsim
+      - nrf52833dk/nrf52833
+      - nrf52840dk/nrf52840
+      - nrf52840dongle/nrf52840
+    extra_args: OVERLAY_CONFIG=overlay-bt_ll_sw_split.conf
+    tags: bluetooth