All revocable trusts are grantor trusts for which the income and deductions are reported by the grantor and the trust does not file tax returns and is essentially disregarded for tax purposes. That is, the activity of the revocable trust is treated as if it was the activity of the grantor.
Internal Revenue Code sections 673-677 and 679, and the related regulations, determine whether a trust is a grantor trust. For a more detailed definition see http://www.irs.gov/businesses/small/article/0,,id=106551,00.html
If the trust is a grantor trust (as evidenced by not filing any tax return) then there is no tax difference for the grantor between the trust making a gift or your father, presumably the grantor, making a gift.
Of course, this is general information and for legal advice or opinion for your particular facts and situation (such as to confirm it is a revocable trust) you would need to consult with an attorney that can review the trust agreement and applicable local law.
There could be potential issues for adhering to the trust agreement (for example, if distribution amounts or percentage are specified in the agreement) when the trust will gift to one or some but not all of the beneficiaries depending on the language of the trust agreement.
Please ask if you need clarification.