A 'chit' is a small piece of paper, often used in basic accounting, to say that someone owes another person a sum of money. In this case, it means 'calling in a favour'. If you call in a favour, you are asking someone to repay a good turn which you did for them on a previous occasion. In other words, the character is saying 'Are you asking me to do this because I'm your friend, or because I owe you a favour?'. And just a bonus tip: Your question should have said, for example 'I came across this phrase in the serial Suits'. The phrasal verb 'go into' can't be used with this meaning. I hope that helps.

Oh someone really notice this line of Harvey from suits. I was confuse too I did'nt get the phrase when he used the word chit. Someone here care to explain whats the meaning of "Are you asking as a friend or are you calling in a chit?"