Garrett was given credit for the jail time he had already served since being taken into custody March 30 after a Superior Court commissioner determined he failed several drug tests while staying in a live-in drug diversion program.
"I'd be surprised if he's not out within three days," Garrett's attorney, Andrew Flier, said. He added that his client decided to leave the drug court program, which required frequent tests and daily counseling, because it was too strict.
"Unfortunately, they were being so restrictive on him that he said he's had enough and he'll be able to prove himself," Flier said.
Commissioner Melissa Widdifield said she was "disappointed" by the decision and wished Garrett good luck.
Garrett, 44, pleaded guilty last year to attempted possession of cocaine-based narcotics based on a 2004 arrest and was placed in a less stringent, outpatient rehab program.
While on probation in the cocaine case, he was arrested Jan. 14 for trying to ride a Los Angeles subway train without a ticket. Police said they found suspected narcotics and prosecutors filed a felony heroin possession charge against him.
Garrett pleaded not guilty in that case.
Several weeks later, he checked into the live-in program after he failed a drug test and admitted he needed more help.
Garrett has appeared in three dozen films, mostly in the 1970s and 1980s, and has released 10 music albums.