diff --git a/src/include/lwip/altcp_tls.h b/src/include/lwip/altcp_tls.h
index 2cef9cd8..fb554a8d 100644
--- a/src/include/lwip/altcp_tls.h
+++ b/src/include/lwip/altcp_tls.h
@@ -56,7 +56,7 @@ extern "C" {
 #endif
 
 /** @ingroup altcp_tls
- * ALTCP_TLS configuration handle, content depends on port (e.g. mbedtls) 
+ * ALTCP_TLS configuration handle, content depends on port (e.g. mbedtls)
  */
 struct altcp_tls_config;