Who takes the throne Abu l'Hasan's throne as noted in the nonfiction book, The Adventures of Ibn Battuta, a Muslim Traveler of the Fourteenth Century?

Abu l'Hasan, the Sultan of Morocco, precedes his son, Abu 'Inan. Abu l'Hasan attempts to expand his rule to the city of Tunis, but only takes tenuous control of it. Ibn Battuta finds him in Tunis on his way back to Morocco, where he meets with him and expresses his loyalty to the Sultan. Shortly afterwards, Abu l'Hasan is driven from his throne by his son.