Clean multiple new lines in a text

/**
 * Clean duplicates new line
 *
 */
  function cleanNewLine($text)  {
    $newLine = "\r\n";
    $strRes = '';

    $posNewLine = strpos($text, $newLine);
    if ($posNewLine===false) {
      $strRes = $text;

    } else {
      $startText = substr($text, 0, $posNewLine+2);
      $endText = substr($text, $posNewLine+2);
      $strRes .= $startText."";

      // Remove duplicate new line if exists
      $posNewLine = strpos($endText, $newLine);
      while($posNewLine===0) {
        $endText = substr($endText, $posNewLine+2);
        $posNewLine = strpos($endText, $newLine);
      }

      $strRes .= self::cleanNewLine($endText);
    }

    return $strRes;
  }