my $callbackFunc = \&Helper::func;
my $obj = new BigOne ( vals => $callbackFunc);

##</code><code>##

my $vals = shift;
.... 
if (ref $vals eq 'CODE') {
   ...........
    my $kv = &$vals( id => $selected, dbh => $$self{dbh} );
   ..............
};
....

##</code><code>##

my $callbackFunc = \&Helper::func( additional_parameter => 'xxx'  );

##</code><code>##

my $kv = &$vals( id => $selected, dbh => $$self{dbh}, additional_parameter => 'xxx'  );

##</code><code>##

my $kv = &$vals( id => $selected, dbh => $$self{dbh});