download helper codeigniter, file download selalu 0 byte

halo selamat pagi, saya mau bertanya saya sedang mencoba membuat link download file dicodeigniter, fungsinya sudah berjalan/redirectnya sudah benar. Hanya saja file yang saya download selalu 0 byte padahal di folder tempat uploadnya filenya memiliki size

public function download() {
      //load the download helper
      $this->load->helper('download');
      $get_file = $this->teknis->get_by_id_dak2016($this->uri->segment(12));
      $user_data['file_laporan'] = $get_file->file_laporan;
      //Get the file from whatever the user uploaded (NOTE: Users needs to upload first), @See http://localhost/CI/index.php/upload
      $data = file_get_contents("./uploads/realisasi_tahun_2016/");
      //Read the file's contents
      $name = $user_data['file_laporan'];

      //use this function to force the session/browser to download the file uploaded by the user
      force_download($name, $data);
   }

kira-kira apa ada yang salah discript saya diatas?