bluetooth: host: Add support for extended feature set feature

This commit adds support for the extended feature set
feature. This includes:
- hci boilerplate
- kconfigs, including one for a max local feature page
- reading remote features is done by a command and callback
- this is not linked into the auto feature request on
connection as this procedure can take quite a few connection
events, and we do not want to delay the user
- added the commands to the bt shell

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

Author: sean-madigan

include/zephyr/bluetooth/bluetooth.h

@@ -34,6 +34,7 @@
 #include <zephyr/bluetooth/gap.h>
 #include <zephyr/bluetooth/addr.h>
 #include <zephyr/bluetooth/crypto.h>
+#include <zephyr/bluetooth/hci_types.h>
 #include <zephyr/bluetooth/classic/classic.h>
 #include <zephyr/net_buf.h>
 #include <zephyr/sys/slist.h>
@@ -71,11 +72,16 @@ extern "C" {
 #define BT_ID_DEFAULT 0
 
 /**
- * @brief Number of octets for local supported
+ * @brief Number of octets for local supported features
  *
- * The value of 8 correspond to page 0 in the LE Controller supported features
+ * The value of 8 correspond to page 0 in the LE Controller supported features.
+ * 24 bytes are required for all subsequent supported feature pages.
  */
-#define BT_LE_LOCAL_SUPPORTED_FEATURES_SIZE 8
+#define BT_LE_LOCAL_SUPPORTED_FEATURES_SIZE                                                        \
+	(BT_HCI_LE_BYTES_PAGE_0_FEATURE_PAGE +                                                     \
+	 COND_CODE_1(CONFIG_BT_LE_MAX_LOCAL_SUPPORTED_FEATURE_PAGE,                                \
+		CONFIG_BT_LE_MAX_LOCAL_SUPPORTED_FEATURE_PAGE * BT_HCI_LE_BYTES_PER_FEATURE_PAGE,  \
+		(0U)))
 
 /** Opaque type representing an advertiser. */
 struct bt_le_ext_adv;

include/zephyr/bluetooth/conn.h

@@ -252,6 +252,27 @@ struct bt_conn_le_subrate_changed {
 	uint16_t supervision_timeout;
 };
 
+/** Read all remote features complete callback params */
+struct bt_conn_le_read_all_remote_feat_complete {
+	/** @brief  HCI Status from LE Read All Remote Features Complete event.
+	 *
+	 *  The remaining parameters will be unchanged if status is not @ref BT_HCI_ERR_SUCCESS.
+	 */
+	uint8_t status;
+	/** Number of pages supported by remote device. */
+	uint8_t max_remote_page;
+	/** Number of pages fetched from remote device. */
+	uint8_t max_valid_page;
+	/** @brief Pointer to array of size 248, with feature bits of remote supported features.
+	 *
+	 *  Page 0 being 8 bytes, with the following 10 pages of 24 bytes.
+	 *  Refer to BT_LE_FEAT_BIT_* for values.
+	 *  Refer to the BT_FEAT_LE_* macros for value comparison.
+	 *  See Bluetooth Core Specification, Vol 6, Part B, Section 4.6.
+	 */
+	const uint8_t *features;
+};
+
 /** Connection Type */
 enum __packed bt_conn_type {
 	/** LE Connection Type */
@@ -1186,6 +1207,24 @@ int bt_conn_le_subrate_set_defaults(const struct bt_conn_le_subrate_param *param
 int bt_conn_le_subrate_request(struct bt_conn *conn,
 			       const struct bt_conn_le_subrate_param *params);
 
+/** @brief Read remote feature pages.
+ *
+ *  Request remote feature pages, from 0 up to pages_requested or the number
+ *  of pages supported by the peer. There is a maximum of 10 pages.
+ *  This function will trigger the @ref read_all_remote_feat_complete callback
+ *  when the procedure is completed.
+ *
+ *  @kconfig_dep{CONFIG_BT_LE_EXTENDED_FEAT_SET}
+ *
+ *  @param conn @ref BT_CONN_TYPE_LE connection object.
+ *  @param pages_requested Number of feature pages to be requested from peer.
+ *                         There is a maximum of 10 pages.
+ *
+ *  @return Zero on success or (negative) error code on failure.
+ *  @return -EINVAL @p conn is not a valid @ref BT_CONN_TYPE_LE connection.
+ */
+int bt_conn_le_read_all_remote_features(struct bt_conn *conn, uint8_t pages_requested);
+
 /** @brief Update the connection parameters.
  *
  *  If the local device is in the peripheral role then updating the connection
@@ -1877,6 +1916,25 @@ struct bt_conn_cb {
 				const struct bt_conn_le_subrate_changed *params);
 #endif /* CONFIG_BT_SUBRATING */
 
+#if defined(CONFIG_BT_LE_EXTENDED_FEAT_SET)
+	/** @brief Read all remote features complete event.
+	 *
+	 *  This callback notifies the application that a 'read all remote
+	 *  features' procedure of the connection is completed. The other params
+	 *  will not be populated if status is not @ref BT_HCI_ERR_SUCCESS.
+	 *
+	 *  This callback can be triggered by calling @ref
+	 *  bt_conn_le_read_all_remote_features or by the procedure running
+	 *  autonomously in the controller.
+	 *
+	 *  @param conn   Connection object.
+	 *  @param params Remote features.
+	 */
+	void (*read_all_remote_feat_complete)(
+		struct bt_conn *conn,
+		const struct bt_conn_le_read_all_remote_feat_complete *params);
+#endif /* CONFIG_BT_LE_EXTENDED_FEAT_SET */
+
 #if defined(CONFIG_BT_CHANNEL_SOUNDING)
 	/** @brief LE CS Read Remote Supported Capabilities Complete event.
 	 *

include/zephyr/bluetooth/hci_types.h

@@ -207,7 +207,7 @@ struct bt_hci_cmd_hdr {
 #define BT_LE_FEAT_BIT_CHANNEL_SOUNDING         46
 #define BT_LE_FEAT_BIT_CHANNEL_SOUNDING_HOST    47
 #define BT_LE_FEAT_BIT_CHANNEL_SOUNDING_TONE_QUAL_IND    48
-#define BT_LE_FEAT_BIT_LL_EXTENDED_FEAT_SET     63
+#define BT_LE_FEAT_BIT_EXTENDED_FEAT_SET        63
 
 #define BT_LE_FEAT_TEST(feat, n)                (feat[(n) >> 3] & \
 						 BIT((n) & 7))
@@ -284,6 +284,8 @@ struct bt_hci_cmd_hdr {
 						  BT_LE_FEAT_BIT_CHANNEL_SOUNDING)
 #define BT_FEAT_LE_CHANNEL_SOUNDING_HOST(feat)    BT_LE_FEAT_TEST(feat, \
 						  BT_LE_FEAT_BIT_CHANNEL_SOUNDING_HOST)
+#define BT_FEAT_LE_EXTENDED_FEAT_SET(feat)        BT_LE_FEAT_TEST(feat, \
+						  BT_LE_FEAT_BIT_EXTENDED_FEAT_SET)
 
 #define BT_FEAT_LE_CIS(feat)            (BT_FEAT_LE_CIS_CENTRAL(feat) | \
 					BT_FEAT_LE_CIS_PERIPHERAL(feat))
@@ -2438,6 +2440,22 @@ struct bt_hci_cp_le_tx_test_v4 {
 	uint8_t  ant_ids[0];
 } __packed;
 
+#define BT_HCI_OP_LE_READ_ALL_LOCAL_SUPPORTED_FEATURES BT_OP(BT_OGF_LE, 0x0087) /* 0x2087 */
+struct bt_hci_rp_le_read_all_local_supported_features {
+	uint8_t  status;
+	uint8_t  max_page;
+	uint8_t  features[248];
+} __packed;
+
+#define BT_READ_ALL_LOCAL_FEATURES_SUPPORTED(supported_commands)                                   \
+	BT_CMD_TEST(supported_commands, 47, 2)
+
+#define BT_HCI_OP_LE_READ_ALL_REMOTE_FEATURES BT_OP(BT_OGF_LE, 0x0088) /* 0x2088 */
+struct bt_hci_cp_le_read_all_remote_features {
+	uint16_t handle;
+	uint8_t  pages_requested;
+} __packed;
+
 #define BT_HCI_TX_TEST_POWER_MIN -0x7F
 #define BT_HCI_TX_TEST_POWER_MAX 0x14
 
@@ -3552,6 +3570,20 @@ struct bt_hci_evt_le_cis_established_v2 {
 	uint8_t  framing;
 } __packed;
 
+#define BT_HCI_EVT_LE_READ_ALL_REMOTE_FEAT_COMPLETE 0x2b
+
+#define BT_HCI_LE_FEATURE_PAGE_MAX          10
+#define BT_HCI_LE_BYTES_PER_FEATURE_PAGE    24
+#define BT_HCI_LE_BYTES_PAGE_0_FEATURE_PAGE 8
+
+struct bt_hci_evt_le_read_all_remote_feat_complete {
+	uint8_t  status;
+	uint16_t handle;
+	uint8_t  max_remote_page;
+	uint8_t  max_valid_page;
+	uint8_t  features[248];
+} __packed;
+
 #define BT_HCI_LE_CS_INITIATOR_ROLE_MASK BIT(0)
 #define BT_HCI_LE_CS_REFLECTOR_ROLE_MASK BIT(1)
 
@@ -4024,6 +4056,8 @@ struct bt_hci_evt_le_cs_procedure_enable_complete {
 #define BT_EVT_MASK_LE_ENH_CONN_COMPLETE_V2        BT_EVT_BIT(40)
 #define BT_EVT_MASK_LE_CIS_ESTABLISHED_V2          BT_EVT_BIT(41)
 
+#define BT_EVT_MASK_LE_READ_ALL_REMOTE_FEAT_COMPLETE BT_EVT_BIT(42)
+
 #define BT_EVT_MASK_LE_CS_READ_REMOTE_SUPPORTED_CAPABILITIES_COMPLETE BT_EVT_BIT(43)
 #define BT_EVT_MASK_LE_CS_READ_REMOTE_FAE_TABLE_COMPLETE              BT_EVT_BIT(44)
 #define BT_EVT_MASK_LE_CS_SECURITY_ENABLE_COMPLETE                    BT_EVT_BIT(45)

subsys/bluetooth/Kconfig

@@ -115,6 +115,21 @@ config BT_CONN_TX
 	help
 	  Hidden configuration that is true if ACL or broadcast ISO is enabled
 
+config BT_LE_MAX_LOCAL_SUPPORTED_FEATURE_PAGE
+	int "Maximum supported feature page"
+	default 0
+	range 0 10
+	depends on BT_LE_EXTENDED_FEAT_SET
+	help
+	  Maximum supported feature page that can be stored locally and fetched
+	  from the remote connection with the LL Extended Feature Set feature.
+
+config BT_LE_EXTENDED_FEAT_SET
+	bool "LL Extended Feature Set"
+	depends on !HAS_BT_CTLR || BT_CTLR_EXTENDED_FEAT_SET_SUPPORT
+	help
+	  Enable support for the LL Extended Feature Set feature.
+
 if BT_CONN
 config BT_HCI_ACL_FLOW_CONTROL
 	bool "Controller to Host ACL flow control support"

subsys/bluetooth/common/Kconfig

@@ -119,7 +119,7 @@ config BT_BUF_ACL_RX_COUNT
 
 config BT_BUF_EVT_RX_SIZE
 	int "Maximum supported HCI Event buffer length"
-	default $(UINT8_MAX) if (BT_EXT_ADV && BT_OBSERVER) || BT_PER_ADV_SYNC || BT_DF_CONNECTION_CTE_RX || BT_CLASSIC || BT_CHANNEL_SOUNDING
+	default $(UINT8_MAX) if (BT_EXT_ADV && BT_OBSERVER) || BT_PER_ADV_SYNC || BT_DF_CONNECTION_CTE_RX || BT_CLASSIC || BT_CHANNEL_SOUNDING || BT_LE_EXTENDED_FEAT_SET
 	# LE Read Supported Commands command complete event.
 	default 68
 	range 68 $(UINT8_MAX)

subsys/bluetooth/controller/Kconfig

@@ -128,6 +128,9 @@ config BT_CTLR_SUBRATING_SUPPORT
 config BT_CTLR_CHANNEL_SOUNDING_SUPPORT
 	bool
 
+config BT_CTLR_EXTENDED_FEAT_SET_SUPPORT
+	bool
+
 # Virtual option that all local LL implementations should select
 config HAS_BT_CTLR
 	bool
@@ -1174,6 +1177,14 @@ config BT_CTLR_CHANNEL_SOUNDING
 	  Enable support for Bluetooth 6.0 Channel Sounding in the
 	  Controller.
 
+config BT_CTLR_EXTENDED_FEAT_SET
+	bool "LL Extended Feature Set support"
+	depends on BT_CTLR_EXTENDED_FEAT_SET_SUPPORT
+	default y if BT_LE_EXTENDED_FEAT_SET
+	help
+	  Enable support for Bluetooth 6.0 LL Extended Feature Set
+	  in the Controller.
+
 rsource "Kconfig.df"
 rsource "Kconfig.ll_sw_split"
 rsource "Kconfig.dtm"

subsys/bluetooth/host/conn.c

@@ -3289,6 +3289,53 @@ int bt_conn_le_subrate_request(struct bt_conn *conn,
 }
 #endif /* CONFIG_BT_SUBRATING */
 
+#if defined(CONFIG_BT_LE_EXTENDED_FEAT_SET)
+void notify_read_all_remote_feat_complete(struct bt_conn *conn,
+					  struct bt_conn_le_read_all_remote_feat_complete *params)
+{
+	struct bt_conn_cb *callback;
+
+	SYS_SLIST_FOR_EACH_CONTAINER(&conn_cbs, callback, _node) {
+		if (callback->read_all_remote_feat_complete != NULL) {
+			callback->read_all_remote_feat_complete(conn, params);
+		}
+	}
+
+	STRUCT_SECTION_FOREACH(bt_conn_cb, cb)
+	{
+		if (cb->read_all_remote_feat_complete != NULL) {
+			cb->read_all_remote_feat_complete(conn, params);
+		}
+	}
+}
+
+int bt_conn_le_read_all_remote_features(struct bt_conn *conn, uint8_t pages_requested)
+{
+	struct bt_hci_cp_le_read_all_remote_features *cp;
+	struct net_buf *buf;
+
+	if (!bt_conn_is_type(conn, BT_CONN_TYPE_LE)) {
+		LOG_DBG("Invalid connection type: %u for %p", conn->type, conn);
+		return -EINVAL;
+	}
+
+	if (pages_requested > BT_HCI_LE_FEATURE_PAGE_MAX) {
+		return -EINVAL;
+	}
+
+	buf = bt_hci_cmd_alloc(K_FOREVER);
+	if (buf == NULL) {
+		return -ENOBUFS;
+	}
+
+	cp = net_buf_add(buf, sizeof(*cp));
+	cp->handle = sys_cpu_to_le16(conn->handle);
+	cp->pages_requested = pages_requested;
+
+	return bt_hci_cmd_send_sync(BT_HCI_OP_LE_READ_ALL_REMOTE_FEATURES, buf, NULL);
+}
+#endif /* CONFIG_BT_LE_EXTENDED_FEAT_SET */
+
 #if defined(CONFIG_BT_CHANNEL_SOUNDING)
 void notify_remote_cs_capabilities(struct bt_conn *conn, uint8_t status,
 				   struct bt_conn_le_cs_capabilities *params)

subsys/bluetooth/host/conn_internal.h

@@ -512,6 +512,9 @@ void notify_path_loss_threshold_report(struct bt_conn *conn,
 void notify_subrate_change(struct bt_conn *conn,
 			   struct bt_conn_le_subrate_changed params);
 
+void notify_read_all_remote_feat_complete(struct bt_conn *conn,
+					  struct bt_conn_le_read_all_remote_feat_complete *params);
+
 void notify_remote_cs_capabilities(struct bt_conn *conn,
 				   uint8_t status,
 				   struct bt_conn_le_cs_capabilities *params);