Bluetooth: Add framework for Extended Controller Information

This command is used to retrieve the current state and basic
information of a controller. It is typically used right after
getting the response to the Read Controller Index List command
or an Index Added event (or its extended counterparts).

When any of the values in the EIR_Data field changes, the event
Extended Controller Information Changed will be used to inform
clients about the updated information.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Michał Narajowski <michal.narajowski@codecoup.pl>

include/net/bluetooth/hci.h

@@ -208,6 +208,7 @@ enum {
 	HCI_MGMT_INDEX_EVENTS,
 	HCI_MGMT_UNCONF_INDEX_EVENTS,
 	HCI_MGMT_EXT_INDEX_EVENTS,
+	HCI_MGMT_EXT_INFO_EVENTS,
 	HCI_MGMT_OPTION_EVENTS,
 	HCI_MGMT_SETTING_EVENTS,
 	HCI_MGMT_DEV_CLASS_EVENTS,

include/net/bluetooth/mgmt.h

@@ -586,6 +586,18 @@ struct mgmt_rp_get_adv_size_info {
 
 #define MGMT_OP_START_LIMITED_DISCOVERY	0x0041
 
+#define MGMT_OP_READ_EXT_INFO		0x0042
+#define MGMT_READ_EXT_INFO_SIZE		0
+struct mgmt_rp_read_ext_info {
+	bdaddr_t bdaddr;
+	__u8     version;
+	__le16   manufacturer;
+	__le32   supported_settings;
+	__le32   current_settings;
+	__le16   eir_len;
+	__u8     eir[0];
+} __packed;
+
 #define MGMT_EV_CMD_COMPLETE		0x0001
 struct mgmt_ev_cmd_complete {
 	__le16	opcode;
@@ -800,3 +812,9 @@ struct mgmt_ev_advertising_added {
 struct mgmt_ev_advertising_removed {
 	__u8    instance;
 } __packed;
+
+#define MGMT_EV_EXT_INFO_CHANGED	0x0025
+struct mgmt_ev_ext_info_changed {
+	__le16	eir_len;
+	__u8	eir[0];
+} __packed;

net/bluetooth/mgmt.c

@@ -104,6 +104,7 @@ static const u16 mgmt_commands[] = {
 	MGMT_OP_REMOVE_ADVERTISING,
 	MGMT_OP_GET_ADV_SIZE_INFO,
 	MGMT_OP_START_LIMITED_DISCOVERY,
+	MGMT_OP_READ_EXT_INFO,
 };
 
 static const u16 mgmt_events[] = {
@@ -141,6 +142,7 @@ static const u16 mgmt_events[] = {
 	MGMT_EV_LOCAL_OOB_DATA_UPDATED,
 	MGMT_EV_ADVERTISING_ADDED,
 	MGMT_EV_ADVERTISING_REMOVED,
+	MGMT_EV_EXT_INFO_CHANGED,
 };
 
 static const u16 mgmt_untrusted_commands[] = {
@@ -149,6 +151,7 @@ static const u16 mgmt_untrusted_commands[] = {
 	MGMT_OP_READ_UNCONF_INDEX_LIST,
 	MGMT_OP_READ_CONFIG_INFO,
 	MGMT_OP_READ_EXT_INDEX_LIST,
+	MGMT_OP_READ_EXT_INFO,
 };
 
 static const u16 mgmt_untrusted_events[] = {
@@ -162,6 +165,7 @@ static const u16 mgmt_untrusted_events[] = {
 	MGMT_EV_NEW_CONFIG_OPTIONS,
 	MGMT_EV_EXT_INDEX_ADDED,
 	MGMT_EV_EXT_INDEX_REMOVED,
+	MGMT_EV_EXT_INFO_CHANGED,
 };
 
 #define CACHE_TIMEOUT	msecs_to_jiffies(2 * 1000)
@@ -862,6 +866,52 @@ static int read_controller_info(struct sock *sk, struct hci_dev *hdev,
 				 sizeof(rp));
 }
 
+static int read_ext_controller_info(struct sock *sk, struct hci_dev *hdev,
+				    void *data, u16 data_len)
+{
+	struct mgmt_rp_read_ext_info rp;
+
+	BT_DBG("sock %p %s", sk, hdev->name);
+
+	hci_dev_lock(hdev);
+
+	memset(&rp, 0, sizeof(rp));
+
+	bacpy(&rp.bdaddr, &hdev->bdaddr);
+
+	rp.version = hdev->hci_ver;
+	rp.manufacturer = cpu_to_le16(hdev->manufacturer);
+
+	rp.supported_settings = cpu_to_le32(get_supported_settings(hdev));
+	rp.current_settings = cpu_to_le32(get_current_settings(hdev));
+
+	rp.eir_len = cpu_to_le16(0);
+
+	hci_dev_unlock(hdev);
+
+	/* If this command is called at least once, then the events
+	 * for class of device and local name changes are disabled
+	 * and only the new extended controller information event
+	 * is used.
+	 */
+	hci_sock_set_flag(sk, HCI_MGMT_EXT_INFO_EVENTS);
+	hci_sock_clear_flag(sk, HCI_MGMT_DEV_CLASS_EVENTS);
+	hci_sock_clear_flag(sk, HCI_MGMT_LOCAL_NAME_EVENTS);
+
+	return mgmt_cmd_complete(sk, hdev->id, MGMT_OP_READ_EXT_INFO, 0, &rp,
+				 sizeof(rp));
+}
+
+static int ext_info_changed(struct hci_dev *hdev, struct sock *skip)
+{
+	struct mgmt_ev_ext_info_changed ev;
+
+	ev.eir_len = cpu_to_le16(0);
+
+	return mgmt_limited_event(MGMT_EV_EXT_INFO_CHANGED, hdev, &ev,
+				  sizeof(ev), HCI_MGMT_EXT_INFO_EVENTS, skip);
+}
+
 static int send_settings_rsp(struct sock *sk, u16 opcode, struct hci_dev *hdev)
 {
 	__le32 settings = cpu_to_le32(get_current_settings(hdev));
@@ -2995,6 +3045,7 @@ static int set_local_name(struct sock *sk, struct hci_dev *hdev, void *data,
 
 		err = mgmt_limited_event(MGMT_EV_LOCAL_NAME_CHANGED, hdev, data,
 					 len, HCI_MGMT_LOCAL_NAME_EVENTS, sk);
+		ext_info_changed(hdev, sk);
 
 		goto failed;
 	}
@@ -6356,6 +6407,8 @@ static const struct hci_mgmt_handler mgmt_handlers[] = {
 	{ remove_advertising,	   MGMT_REMOVE_ADVERTISING_SIZE },
 	{ get_adv_size_info,       MGMT_GET_ADV_SIZE_INFO_SIZE },
 	{ start_limited_discovery, MGMT_START_DISCOVERY_SIZE },
+	{ read_ext_controller_info,MGMT_READ_EXT_INFO_SIZE,
+						HCI_MGMT_UNTRUSTED },
 };
 
 void mgmt_index_added(struct hci_dev *hdev)
@@ -6494,10 +6547,12 @@ void __mgmt_power_off(struct hci_dev *hdev)
 
 	mgmt_pending_foreach(0, hdev, cmd_complete_rsp, &status);
 
-	if (memcmp(hdev->dev_class, zero_cod, sizeof(zero_cod)) != 0)
+	if (memcmp(hdev->dev_class, zero_cod, sizeof(zero_cod)) != 0) {
 		mgmt_limited_event(MGMT_EV_CLASS_OF_DEV_CHANGED, hdev,
 				   zero_cod, sizeof(zero_cod),
 				   HCI_MGMT_DEV_CLASS_EVENTS, NULL);
+		ext_info_changed(hdev, NULL);
+	}
 
 	new_settings(hdev, match.sk);
 
@@ -7093,9 +7148,11 @@ void mgmt_set_class_of_dev_complete(struct hci_dev *hdev, u8 *dev_class,
 	mgmt_pending_foreach(MGMT_OP_ADD_UUID, hdev, sk_lookup, &match);
 	mgmt_pending_foreach(MGMT_OP_REMOVE_UUID, hdev, sk_lookup, &match);
 
-	if (!status)
+	if (!status) {
 		mgmt_limited_event(MGMT_EV_CLASS_OF_DEV_CHANGED, hdev, dev_class,
 				   3, HCI_MGMT_DEV_CLASS_EVENTS, NULL);
+		ext_info_changed(hdev, NULL);
+	}
 
 	if (match.sk)
 		sock_put(match.sk);
@@ -7126,6 +7183,7 @@ void mgmt_set_local_name_complete(struct hci_dev *hdev, u8 *name, u8 status)
 
 	mgmt_limited_event(MGMT_EV_LOCAL_NAME_CHANGED, hdev, &ev, sizeof(ev),
 			   HCI_MGMT_LOCAL_NAME_EVENTS, cmd ? cmd->sk : NULL);
+	ext_info_changed(hdev, cmd ? cmd->sk : NULL);
 }
 
 static inline bool has_uuid(u8 *uuid, u16 uuid_count, u8 (*uuids)[16])