Devoted pet welcoming first of travellers home (6)
I believe the answer is:
Here is my best explanation:
'devoted' is the definition.
(I've seen this before)
'pet welcoming first of travellers home' is the subsidiary indication.
'pet' becomes 'dog'.
'welcoming' indicates putting letters inside (in sense of \'inviting in\').
'first of' indicates taking the first letters.
'home' becomes 'in' ('he's home' can mean 'he's in').
The first letter of 'travellers' is 't'.
'dog' going around 'tin' is 'doting'.
(Other definitions for doting that I've seen before include "Blindly affectionate", "Excessively fond", "Showing excessive love", "Affectionate", "excessive worship", "Showing great fondness as for a spouse", "Foolishly loving and indulgent", "Overly fond of, say spouse", "Indulgent" and "Overly fond, as husband may be".)