ES 5.0+ geo_point type field not work with Grafana worldmap

I would like to use ES document with geo_point type field as data source to draw points in Grafana worldmap panel.

To work with Grafana worldmap, we need to set "geohash: true" option in geo_point type mapping.
Grafana worldmap document
geohash option

But the geo_hash option is no longer supported since ES5.0
https://www.elastic.co/guide/en/elasticsearch/reference/5.0/breaking_50_mapping_changes.html#_literal_geo_point_literal_fields

So, Can you advise how to make data field for Grafana worldmap?
Thanks!

I've also post the same issues to elasticsearch.
https://github.com/grafana/worldmap-panel/issues/231
Blockquote

Hi @Kevin_Kuei

Grafana is not an Elastic product so I do not think we will be able to help with this. Perhaps you can find help on their website?