My Mum had a radio that she had on all the time in her room, when she was bedbound near the end, she loved listening to it.
A doll as she was always looking for her children, so this settled her down if he is always looking for something/someone try and get a toy alternative, it worked so well with my Mum.
Something to twiddle\fiddle with like a twiddle blanket.
I did a scrapbook with pictures of all the family and a family tree as they do forget who you are, and it also helped staff members and it engaged my Mum, I included pictures of her parents as she was insistent that I was stopping her going to see them and stopping her going to school so older pictures were included, (she thought I was her parent at one stage)
Food - anything they like, soft drinks as they do forget to drink and most end up with a UTI, when you visit make sure he drinks loads while you are there as staff are so busy sometimes it gets overlooked, I used to take my Mum cartons of Ribena or milkshake and she used to really like that even though she never drank it before she got ill.
Slippers make sure they are ones that can be taken off and put on easily.
A blanket with pictures on for his armchair.
A cardigan, make sure it can be tumble dried.
Toiletries are always welcome.
Make sure everything is named as they wash everything, and you do end up with other resident's clothes.
I know you asked for gift ideas, but I thought I would add some ideas of what helped my Mum as it is scary for everyone, My Dad had to learn to not argue back when she said something and just agree as she would get so upset, I got used to being called all different names and just answered her, she even called my DH carrot once instead of his name.