How to add Facet and Join together?

Question

Document-oriented bases

I execute the following query
q=type:productVariant
fq=saugkanaele:*
facet.field:saugkanaele
result

"response":{"numFound":210,"start":0,"docs":[...]},
"facet_fields":{
      "saugkanaele":[
        "1.0",126,
        "2.0",77,
        "4.0",7]}

but I need to get products as a result of the request and not options as above, so I add
{!join from=main_parent_id to=id} type:(productVariant)
and I get an array of documents type=product everything is as it should, but facet counts become 0
i.e. first joins and in the resulting documents the type=product field saugkanaele is not available
, maybe someone knows how to first calculate the count in productVariant and in the selection so that type=product gets instead of options
Thank you