Remove media button from the custom post type support editor

Below code removes the medial button from other editors as well..

how to remove the editor from the post type support editor

   add_action('admin_head', 'remove_mediabuttons');


function remove_mediabuttons()
{
    global $post;

    if($post-post_type == 'custom_post_type'  current_user_can('edit_post') )
    {
        remove_action( 'media_buttons', 'media_buttons' );
    }
}