can you/your father still log in to the phone ??. Is it already paired with any computer ?.
If that is not the case maybe a competent shop/person can recover some data but the options on apple
devices are limited.
If the data on the phone is valuable and it is just a case of broken screen, depending on model a shop,
not apple who only replace supported devices for an impressive fee might be able to remove the broken
screen, hook up a working one and with help from your father recover data or even fix the phone.
Software for this kind of problem is very limited and as far as I am aware not available for linux.
Sorry, this kind of situation is why backups are so important, not just on phones..