Bluetooth: Expose hardware error code as debugfs entry

When the Hardware Error event is send by the controller, the Bluetooth
core stores the error code. Expose it via debugfs so it can be retrieved
later on.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

net/bluetooth/hci_debugfs.c

@@ -256,6 +256,9 @@ void hci_debugfs_create_common(struct hci_dev *hdev)
 			   &hdev->manufacturer);
 	debugfs_create_u8("hci_version", 0444, hdev->debugfs, &hdev->hci_ver);
 	debugfs_create_u16("hci_revision", 0444, hdev->debugfs, &hdev->hci_rev);
+	debugfs_create_u8("hardware_error", 0444, hdev->debugfs,
+			  &hdev->hw_error_code);
+
 	debugfs_create_file("device_list", 0444, hdev->debugfs, hdev,
 			    &device_list_fops);
 	debugfs_create_file("blacklist", 0444, hdev->debugfs, hdev,