My solution:
- In the contextual filter field add a Geofield proximity filter - something like "Content: Location (field_location) - proximity". Set the radius distance at the bottom.
- Under "When the filter value is NOT available" select "PHP Code"
- Enter the following PHP. The return value is the argument that is passed to the filter.
$node = menu_get_object(); $value = field_get_items('node', $node, 'field_location'); $lat = $value[0]['lat']; $lon= $value[0]['lon']; return ($lat . ', ' . $lon);
Figured this out from this page https://drupal.org/node/2014345