Bagaimana cara upload file pada Framework Codeigniter ke DB

Assalam,.. begini caranya :
// Views index.php
<form action='<?php echo base_url(); ?>upload/index' method='POST'>
<inptut type='text' name='judul'>
<inptut type='file' name='file'>
<inptut type='submit' name='submit' value='Proses Upload'>
</form>
 
// Controllers Upload.php
function index(){
$config['upload_path'] = 'asset/file/';
$config['allowed_types'] = 'gif|jpg|png|JPG|JPEG|swf';
$config['max_size'] = '3000'; // kb
$this->load->library('upload', $config);
$this->upload->do_upload('file');
$hasil=$this->upload->data();
$this->mod_upload->upload_file();
redirect('upload/index');
}
 
// Models Mod_upload.php
function upload_file($fileupload,$seo){
$data = array('judul'=>$this->db->escape_str($this->input->post('judul')),
              'gambar'=>$hasil['file_name']);
$this->db->insert('table_file',$data);
}