Using strip_tags for form validation with allowable_tags
$this->form_validation->set_rules('description', 'Description', 'callback_description_check');public function direction_check($str){ return strip_tags($text, '<p><a>'); }Best way would be to create your own callback function, which you can modify according to your needs.
you could make a callback
function callback_strip_tags_custom($text){ return strip_tags($text, '<p><a>');}