How do you daisy chain a Cisco IP phone to a PC if they are supposed to be on separate Vlans?

According to my Cisco book, voice and data need to be on separate vlans. And further, different Vlans are always different subnets. But where I work, the IP phone is daisy chained to the PC from the the switch port. So, the phone is plugged into the wall going to a PoE switch port, and the PC is plugged into the phone with a short patch cable. So one switch port and two vlans? Or one switch port and QoS managed flow on one Vlan? OK, so the frame bound to the PC has to go through the phone. I can't find any info on how this is done. Thanks for any help.