[help] form validasi

function add() { 
 
 
        $jabatan = $this->jabatan_model->get_jabatan()-> result(); 
        foreach($jabatan  as $row) 
        { 
            $data['options_jabatan'][$row->id_jabatan] = $row->nama_jabatan; 
        } 
 
        $this->form_validation->set_rules('username', 'Username', 'required'); 
        $this->form_validation->set_rules('password', 'Password', 'required|min_length[5]'); 
        $this->form_validation->set_rules('id_jabatan', 'Jabatan', 'required'); 
 
        if ($this->form_validation->run() == TRUE) 
        { 
            // save data 
            $siswa = array('username'         => $this->input->post('username'), 
                            'password'        => $this->input->post('password'), 
                            'id_jabatan'    => $this->input->post('id_jabatan') 
                        ); 
            $this->Absen_model->add($user); 
 
            $this->session->set_flashdata('message', 'Satu data siswa berhasil disimpan!'); 
            redirect('absen/add'); 
        } 
        else 
        {     
            $this->load->view('add_view_absen', $data); 
        }     
 
    }

class Absen_model extends Model { 
 
    var $table = 'user'; 
    function get_all(){ 
        return $this->db->get('user')->result(); 
    }   
    function add($user) 
    { 
        $this->db->insert($this->table, $user); 
 

<?php  
 
    echo ! empty($message) ? '<p class="message">' . $message . '</p>': ''; 
 
    $flashmessage = $this->session->flashdata('message'); 
    echo ! empty($flashmessage) ? '<p class="message">' . $flashmessage . '</p>': ''; 
?> 
 
<?php echo form_open('absen');?> 
    <table> 
        <td> 
        <tr> 
        <p>         
        <label for="nis">username</label> 
        <input type="text" class="form_field" name="username" size="30" value="<?php echo set_value('username', isset($default['username']) ? $default['username'] : ''); ?>" /> 
        </p> 
        <?php echo form_error('username', '<p class="field_error">', '</p>');?> 
        </tr> 
        <tr> 
            <p>         
        <label for="nis">password</label> 
        <input type="password" class="form_field" name="password" size="30" value="<?php echo set_value('password', isset($default['password']) ? $default['password'] : ''); ?>" /> 
        </p> 
        <?php echo form_error('password', '<p class="field_error">', '</p>');?> 
        </tr> 
 
        <tr> 
        <label for="nama_jabatan">Jabatan:</label>&nbsp&nbsp&nbsp&nbsp&nbsp 
        <?php echo form_dropdown('id_jabatan', $options_jabatan); ?> 
        </tr>