Trying to get site that have a FILTER value of "PASS" or "."

I know of:

`bcftools view -f PASS filename.vcf.gz`

and 

`bcftools view -f . filename.vcf.gz`

I tried:

`bcftools view -f 'PASS | .' filename.vcf.gz`

but no dice.

Is it possible to get what I am looking for or do I have to filter separately then concat?

    bcftools view -f 'PASS,.' filename.vcf.gz