I don't have kids that age, but I wouldn't even expect the phonecalls to be honest! Your son sounds really, really responsible. Not drinking (this might be down to personal taste...I hated the taste of alcohol when I was younger but still drank it because of peer pressure...but still, good on him) and also telling you his plans for the night, albeit not 100% detailed. Furthermore, he rang you so great!
I think kids at that age should be allowed to have a bit of freedom and trust shown from their parents, just like if they say, "I'm going out tonight", sure I'd like to know generally where they're going but that's all I'd ask really.
At 17, I was out every (and I mean every night) drinking, smoking, shagging, vandalising, terrorising and much, much more. Then I'd get home and do most of the above throughout the morning again
I'd rarely get home by 3PM, and was then out the door again at about 6 
I really don't mean to sound preachy, because I don't want to be. It's just it sounds like you have a lovely, thoughtful son 