Does anyone know if there is a mechanism in the US government that would allow people (like Warren Buffet) who want to pay more in taxes to do exactly that? Se

Does anyone know if there is a mechanism in the US government that would allow people (like Warren Buffet) who want to pay more in taxes to do exactly that? Seems like it could be written into the tax code pretty easily - that is, if the current tax code were even remotely efficient.