从mysql生成的geojson无法正常工作

I have a function in php:

 public static function getGeoJSON() {
 // code that generates geojson from mysql
  return $geojson;
 }

In javascript i call this function:

     var geo = JSON.parse( '<?php echo json_encode($geo) ?>' );

    //this is where I want to put my generated geojson instead of a file.geojson

  d3.json('point.geojson', function(geojson){
    mapDraw(geojson);
    });

like this I want it:

  // replace static file with generated geojson
  d3.json(geo, function(geojson){
    mapDraw(geojson);
    });

I have printed the generated geojson and pasted it into a json file and it works. but when I try to put the

 var geo

as reference instead of the path it fails. Does anyone know why?

Thanks in advance.

    {"type":"FeatureCollection","features":[{"type":"Feature","geometry":{"type":"Point","coordinates":[xx.xxx,xx.xxx]},"properties":{"description":"bad description"}}]}