This is an example of creating an entityreference autocomplete display using views.

Drupal7 User Autocomplete Entityreference Display

$view = new view();
$view->name = 'user_autocomplete_example';
$view->description = '';
$view->tag = 'default';
$view->base_table = 'users';
$view->human_name = 'User Autocomplete Example';
$view->core = 7;
$view->api_version = '3.0';
$view->disabled = FALSE; /* Edit this to true to make a default view disabled initially */

/* Display: Master */
$handler = $view->new_display('default', 'Master', 'default');
$handler->display->display_options['use_more_always'] = FALSE;
$handler->display->display_options['access']['type'] = 'perm';
$handler->display->display_options['access']['perm'] = 'access user profiles';
$handler->display->display_options['cache']['type'] = 'none';
$handler->display->display_options['query']['type'] = 'views_query';
$handler->display->display_options['exposed_form']['type'] = 'basic';
$handler->display->display_options['pager']['type'] = 'full';
$handler->display->display_options['style_plugin'] = 'default';
$handler->display->display_options['row_plugin'] = 'fields';
/* Field: User: Name */
$handler->display->display_options['fields']['name']['id'] = 'name';
$handler->display->display_options['fields']['name']['table'] = 'users';
$handler->display->display_options['fields']['name']['field'] = 'name';
$handler->display->display_options['fields']['name']['label'] = '';
$handler->display->display_options['fields']['name']['alter']['word_boundary'] = FALSE;
$handler->display->display_options['fields']['name']['alter']['ellipsis'] = FALSE;
$handler->display->display_options['fields']['name']['element_label_colon'] = FALSE;
$handler->display->display_options['fields']['name']['link_to_user'] = FALSE;
/* Filter criterion: User: Active */
$handler->display->display_options['filters']['status']['id'] = 'status';
$handler->display->display_options['filters']['status']['table'] = 'users';
$handler->display->display_options['filters']['status']['field'] = 'status';
$handler->display->display_options['filters']['status']['value'] = '1';
$handler->display->display_options['filters']['status']['group'] = 1;
$handler->display->display_options['filters']['status']['expose']['operator'] = FALSE;

/* Display: User Entity Reference Example */
$handler = $view->new_display('entityreference', 'User Entity Reference Example', 'entityreference_1');
$handler->display->display_options['defaults']['title'] = FALSE;
$handler->display->display_options['pager']['type'] = 'some';
$handler->display->display_options['defaults']['style_plugin'] = FALSE;
$handler->display->display_options['style_plugin'] = 'entityreference_style';
$handler->display->display_options['style_options']['search_fields'] = array(
  'name' => 'name',
);
$handler->display->display_options['defaults']['style_options'] = FALSE;
$handler->display->display_options['defaults']['row_plugin'] = FALSE;
$handler->display->display_options['row_plugin'] = 'entityreference_fields';
$handler->display->display_options['defaults']['row_options'] = FALSE;