schema :
{
  enable = "BOOL";
  valid_access_timeout = "INT";
  bad_access_timeout = "INT";
  address = "INT";
  alias = "STRING";
  devices = (
    {
      enable = "BOOL";
      setup = (
        {
          unit = "INT";
          lock = "BOOL";
          odspeed = "BOOL";
        } );
      address = "INT";
      family = "INT";
    },
    {
      enable = "BOOL";
      setup = (
        {
          unit = "INT";
          lock = "BOOL";
          odspeed = "BOOL";
        } );
      address = "INT";
      family = "INT";
    },
    {
      enable = "BOOL";
      setup = (
        {
          serial = "STRING";
        } );
      address = "INT";
      family = "INT";
    } );
);
slaves = (
);