Hello. Ciscoe, Can you help me with my Wisteria?

I have had it since 1955. It appears the trunk of the Wisteria is slowing dying. It is drying out. And today is the first time I noticed dark brown mushrooms growing on the trunk. What does this mean. Do the mushrooms mean there is rot? Can any of this be saved?  It still blooms great in the summer, but the trunk is slowly cracking and drying out. Appreciate your help.

Angela