To the Carter administration's surprise and chagrin, the Senate late Friday voted to prohibit any U.S. concessions on textile tariffs during the multilateral trade negotiations (MTN) going on in Geneva.

By a 58-to-21 vote, the Senate approved an amendment to Export-Import Bank authorizations sponsored by Sen. Ernest Hollings (D-S.C.) that in effect would take textiles out of the MTN.

Special trade representative Robert S. Strauss said yesterday that if the Hollings amendment cannot be knocked out of the conference report on the Export-Import legislation, the effect would be "devastating." Strauss said that the entire trade treaty negotiations could collapse.

If the Hollings amendment stays in the legislation, he predicted that "consideration" would be given by President Carter to a veto. Strauss made clear that the administration will mount a major effort to get the Hollings textile amendment eliminated during the House-Senate conference.

The flap over the amendment illustrates two points. First, the trade negotiations are bucking a protectionist tide, even though their success is considered essential by the administration here and governments in Europe for stimulation of world growth and trade. And second, almost anything can happen, and often does, in the closing days of a congressional session.

American textile interests have been trying for months to find some way of averting what appeared to be the certainty of a moderate reduction in tariffs as part of the MTN. Hollings had introduced his amendment, which prohibits American negotiators from offering tariff cuts on textiles, as a resolution. A hearing was held by the trade subcommittee of the Senate Finance Committee. But there was no committee approval, although Hollings had 50 cosponsors for his resolution.

A companion resolution had been introduced in the House by Reps. Ken Holl and (D-S.C.) and James T. Broyhill (R-N.C.).

But late on Friday, while Strauss was in California drumming up support for the MTN among agricultural interests, and Finance Committee Chairman Russell B. Long (D-La.) was out of town making a speech, Hollings - a veteran Senate tactician - had little trouble getting the textile exclusion tacked onto the Export-Import authorization legislation.

In a telephone interview yesterday, Strauss complained bitterly that the Carter administration had been given no notice of the impending Friday vote. The 56-to-21 vote was a roll call tally defeating a motion to table the Hollings amendment. It was then approved by voice vote.

"It shows what can happen when a bill comes up late in a session," Strauss said. "I consider that I work for the Congress as well as the administration, but if I'm not going to get a chance to be heard - well, this kind of stuff makes me wonder whether I ought to give up and go home."

Strauss' main worry is that his opposite numbers among the European trade negotiators have said repeatedly that if textiles are not part of the MTN, they will withdraw consideration of agricultural matters for which the United States has consistently fought.

Strauss said that manyof the southern senators collected by Hollings in his bipartisan majority stand to suffer because potential concessions on tobacco, citrus and other agricultural product were sure to be lost if textiles stay out of the MTN. He said that "two or three" senators he had talked to over the weekend acknowledged they didn't know what they were voting for.

Textile and apparel manufacturers are edgy about foreign competition although business and profits are at a high level. The likely cut in textile tariffs, which now average about 20 percent, would be about five points over an eight-to-10-year period, or an average of about one-half a percentage point a year.

Strauss blames the success of the Hollings amendment on a rampant spirit of protectionism. But he argues that to exclude textiles from the MTN would be counterproductive to textiles as well as to broader economic interests.

He said that if textiles are excluded, eventually it will weaken efforts to renew the multi-fiber agreements, which put quota limits on the volume of textile imports.

Hollings could not be reached for comment yesterday.