farmOS/modules/farm/farm_mapknitter/farm_mapknitter.module

<?php
/**
 * @file
 * Code for the Farm MapKnitter module.
 */

/**
 * Implements hook_permission().
 */
function farm_mapknitter_permission() {
  $perms = array(
    'administer farm_mapknitter module' => array(
      'title' => t('Administer farm MapKnitter module'),
    ),
  );
  return $perms;
}

/**
 * Implements hook_farm_access_perms().
 */
function farm_mapknitter_farm_access_perms($role) {
  $perms = array();

  // Grant administer permission to Farm Managers.
  if ($role == 'Farm Manager') {
    $perms[] = 'administer farm_mapknitter module';
  }

  return $perms;
}

/**
 * Implements hook_menu().
 */
function farm_mapknitter_menu() {
  $items = array();

  $items['admin/config/farm/mapknitter'] = array(
    'title' => 'MapKnitter',
    'description' => 'Include a MapKnitter layer in your farm maps.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('farm_mapknitter_form'),
    'access arguments' => array('administer farm_mapknitter module'),
  );

  return $items;
}

/**
 * MapKnitter configuration form.
 */
function farm_mapknitter_form($form, &$form_state) {

  // MapKnitter layer title.
  $form['farm_mapknitter_title'] = array(
    '#type' => 'textfield',
    '#title' => t('MapKnitter layer title'),
    '#description' => t('Give your MapKnitter layer a name. This will be used in the layer switcher '),
    '#default_value' => variable_get('farm_mapknitter_title', ''),
  );

  // MapKnitter slug.
  $form['farm_mapknitter_slug'] = array(
    '#type' => 'textfield',
    '#title' => t('MapKnitter Slug'),
    '#description' => t('Enter the unique MapKnitter slug. This would be the [map-slug] part in your MapKnitter map URL: http://mapknitter.org/maps/[map-slug]'),
    '#default_value' => variable_get('farm_mapknitter_slug', ''),
  );

  $form['#submit'][] = 'farm_mapknitter_form_submit';

  return system_settings_form($form);
}

/**
 * Farm MapKnitter form submit function.
 */
function farm_mapknitter_form_submit($form, &$form_state) {
  drupal_flush_all_caches();
}

/**
 * Implements hook_ctools_plugin_api().
 */
function farm_mapknitter_ctools_plugin_api($module = NULL, $api = NULL) {
  if ($module == "openlayers" && $api == "default_openlayers_layers") {
    return array("version" => "1");
  }
  if ($module == "openlayers" && $api == "default_openlayers_maps") {
    return array("version" => "1");
  }
  if ($module == "openlayers" && $api == "default_openlayers_sources") {
    return array("version" => "1");
  }
}