If they have a warrant, they can compel the suspect to unlock the device. Just like if the police has a warrant for your neighbour's house they can't compel yo

If they have a warrant, they can compel the suspect to unlock the device. Just like if the police has a warrant for your neighbour's house they can't compel you to do the breaking and entering. They can either get the suspect to open the door, or do it themselves. If they don't have a big enough ram or strong enough explosives, that's their problem, they can't compel you to lend your tools in the garage.