title: how charp will be replaced by module_param?
body: <p>In  code given below <code>module_param</code> is macro i have used but for character pointer (<code>char *</code>) in type parameter they used <code>charp</code> in place of <code>char *</code>,
  so how this <code>charp</code> will be replaced and with what it will be replaced.</p>
  
  <pre class="lang-c prettyprint-override"><code>static char *whom = "world";
  static int howmany = 1;
  module_param(howmany, int, S_IRUGO);
  module_param(whom, charp, S_IRUGO);
  </code></pre>
  
  <p>Like in  first macro type will be replaced by <code>int</code> but in second macro
  type will be replaced by <code>charp</code> which is not datatype, then how <code>charp</code> will be mapped to <code>char *</code> by <code>module_param</code> macro?</p>