Self-employed health insurance deduction & spouse coverage

In order to qualify for the self-employed health insurance deduction, you cannot be eligible for coverage through a spouses' employer. What does it mean to be "eligible for coverage"? Technically, I (and my child) can join my spouse's insurance plan, but his employer will not pay any of our portion of the costs. Does this count as being eligible for coverage? Since I soon plan to be self-employed, I'm wondering if I can get insurance for myself and my child from the marketplace instead and then get tax deductions on our premiums. Thanks!