Read and display contents from text file in php

Question

I'm sure there are a lot of references out there about reading from text file and display in the browser. but they seem not solving my problem. I'm using CodeIgniter and since I'm new.. I think I missed few things.. even tho I use reference provided by file-uploading codeigniter..(sigh) anyway.. the following are my codes..and I already create upload directory in the server and chmod to 777

application/views/test_page

.....
<form role="form" id="inputForm" action="<?php echo base_url().'upload/do_upload'; ?>" enctype="multipart/form-data">
    <div class="form-group">
         <label>PLEASE SELECT YOUR INPUT FILE * </label>
         <input class="form-control" name="inFile" id="inFile" type="file" required>
    </div>
    <div class="row">
         <div class="col-md-12">
              <p align=right><button type="submit" value="upload" form="inputForm" class="btn btn-primary btn-lg">READ FILE</button>
         </div>
    </div>
</form>

<?php
    if(!empty($dataFile))
    {
        foreach($dataFile as $lines => $value):
          print 'No : '.$lines.': '.$value;
        endforeach;
    }
?>

......

controller/upload as for testing.. I didn't specify the max size/height/width yet since I didn't get the final input file format.. so..

public function do_upload()
    {
            $config['upload_path']          = './upload/';
            $config['allowed_types']        = 'log';
            $config['max_size']             = 0;
            $config['max_width']            = 0;
            $config['max_height']           = 0;
            $config['remove_spaces']        = TRUE;

            $this->load->library('upload', $config);

            if ( ! $this->upload->do_upload('inFile'))
            {
                    $error = array('error' => $this->upload->display_errors());
                     $this->load->view('test_page', $error);
            }
            else
            {
                    $data = array('dataFile' => $this->upload->data());
                    $this->load->view('test_page', $data);
            }
     }

The code seems not working. I got an error "You did not select a file to upload." but my infile value shows the input file that I selected. Can anyone help me?.. thanks.