filter

wpl_is_single_{$post_type}_disabled

Filters whether Likes should be enabled on single posts. The dynamic part of the filter, {$post_type}, allows you to specific the post type where Likes should be enabled.

Parameters

$enabled
bool

Are Post Likes enabled on single posts?

Changelog

How to use this hook

See “How to use actions and filters to customize Jetpack”.

Notes

To use this filter to enable Likes for one of your Custom Post Types, you’ll need to know your post type’s slug. Then, you can use the filter like so (replace {post_type} by your post type slug):
add_filter( 'wpl_is_single_{post_type}_disabled', '__return_true' );