Author: Julia Lawall <Julia.Lawall@lip6.fr> Delete successive tests to the same location. In this case res has already been tested for being NULL, and calling devm_request_and_ioremap will not make it NULL. On the other hand, devm_request_and_ioremap can return NULL on failure. A simplified version of the semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) …