Since the recent updates I no longer have the photo stream on PHOTOs on my mac. Everything is turned on correctly.
Up until the recent update I was able to see my photo stream in the list of albums in Photos on my mac. It's no longer an option. All systems are turned on to allow photo stream and iCloud storage.
MacBook Pro (Retina, 13-inch,Early 2015), OS X Yosemite (10.10.3)