If you are arrested for possession of a controlled substance, the arresting officer will likely confiscate your driver's license and issue you a temporary paper license. You will then need to appear in court for your arraignment, where the judge will determine whether or not to suspend your driver's license.
If you are convicted of possession of a controlled substance, your driver's license will automatically be suspended for a period of time determined by the judge. The length of the suspension will depend on the type of drug you were found in possession of and your prior criminal record.
In addition to a driver's license suspension, you may also face other penalties for possession of a controlled substance such as fines, probation, or even jail time.