But no GPS data is coming.
With that code, you do NOT know that.
Store the value read from the GPS and print it. That way, you'll KNOW whether there is data coming in from the GPS. If not, then perhaps you have the TX and RX lines swapped. If there is, but it doesn't look right, perhaps you have a baud rate issue.
Debugging by guesswork is the worst possible way to debug code.