As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - ON FLIGHT 2093 RETURNED TO FIELD, RIGHT AFTER TAKEOFF THROUGH 3000, THE SMOKE ALARM IN THE BATHROOM WENT OFF. LASTED FOR 2-3 MINUTES AND THEN STOPPED AFTER IT EXTINGUSHED. THE FLIGHT ATTENDANT SAID THE GREEN LIGHT CAME BACK ON. ON THE ALARM THE FLIGHT ATTENDANT SAID HE HAD SMELLED SMOKE IN THE BATHROOM. MAINTENANCE REMOVED AND REPLACED THE SMOKE DETECTOR AS A PRECAUTIONARY MEASURE. AIRCRAFT RETURNED TO SERVICE.