Index: uspace/lib/drv/include/ddf/driver.h
===================================================================
--- uspace/lib/drv/include/ddf/driver.h	(revision d5c1051faf4391647834d99babdd4a44ee5d9700)
+++ uspace/lib/drv/include/ddf/driver.h	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -56,5 +56,5 @@
 	 * device.
 	 */
-	int (*open)(ddf_fun_t *);
+	errno_t (*open)(ddf_fun_t *);
 	
 	/**
@@ -88,17 +88,17 @@
 typedef struct driver_ops {
 	/** Callback method for passing a new device to the device driver */
-	int (*dev_add)(ddf_dev_t *);
+	errno_t (*dev_add)(ddf_dev_t *);
 	
 	/** Ask driver to remove a device */
-	int (*dev_remove)(ddf_dev_t *);
+	errno_t (*dev_remove)(ddf_dev_t *);
 	
 	/** Inform driver a device disappeared */
-	int (*dev_gone)(ddf_dev_t *);
+	errno_t (*dev_gone)(ddf_dev_t *);
 	
 	/** Ask driver to online a specific function */
-	int (*fun_online)(ddf_fun_t *);
+	errno_t (*fun_online)(ddf_fun_t *);
 	
 	/** Ask driver to offline a specific function */
-	int (*fun_offline)(ddf_fun_t *);
+	errno_t (*fun_offline)(ddf_fun_t *);
 } driver_ops_t;
 
@@ -124,14 +124,14 @@
 extern void *ddf_fun_data_get(ddf_fun_t *);
 extern const char *ddf_fun_get_name(ddf_fun_t *);
-extern int ddf_fun_set_name(ddf_fun_t *, const char *);
+extern errno_t ddf_fun_set_name(ddf_fun_t *, const char *);
 extern ddf_dev_t *ddf_fun_get_dev(ddf_fun_t *);
-extern int ddf_fun_bind(ddf_fun_t *);
-extern int ddf_fun_unbind(ddf_fun_t *);
-extern int ddf_fun_online(ddf_fun_t *);
-extern int ddf_fun_offline(ddf_fun_t *);
-extern int ddf_fun_add_match_id(ddf_fun_t *, const char *, int);
+extern errno_t ddf_fun_bind(ddf_fun_t *);
+extern errno_t ddf_fun_unbind(ddf_fun_t *);
+extern errno_t ddf_fun_online(ddf_fun_t *);
+extern errno_t ddf_fun_offline(ddf_fun_t *);
+extern errno_t ddf_fun_add_match_id(ddf_fun_t *, const char *, int);
 extern void ddf_fun_set_ops(ddf_fun_t *, const ddf_dev_ops_t *);
 extern void ddf_fun_set_conn_handler(ddf_fun_t *, async_port_handler_t);
-extern int ddf_fun_add_to_category(ddf_fun_t *, const char *);
+extern errno_t ddf_fun_add_to_category(ddf_fun_t *, const char *);
 
 #endif
Index: uspace/lib/drv/include/ddf/interrupt.h
===================================================================
--- uspace/lib/drv/include/ddf/interrupt.h	(revision d5c1051faf4391647834d99babdd4a44ee5d9700)
+++ uspace/lib/drv/include/ddf/interrupt.h	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -50,7 +50,7 @@
 typedef void interrupt_handler_t(ipc_call_t *, ddf_dev_t *);
 
-extern int register_interrupt_handler(ddf_dev_t *, int, interrupt_handler_t *,
+extern errno_t register_interrupt_handler(ddf_dev_t *, int, interrupt_handler_t *,
     const irq_code_t *, cap_handle_t *);
-extern int unregister_interrupt_handler(ddf_dev_t *, cap_handle_t);
+extern errno_t unregister_interrupt_handler(ddf_dev_t *, cap_handle_t);
 
 #endif
Index: uspace/lib/drv/include/ddf/log.h
===================================================================
--- uspace/lib/drv/include/ddf/log.h	(revision d5c1051faf4391647834d99babdd4a44ee5d9700)
+++ uspace/lib/drv/include/ddf/log.h	(revision e211ea04fccf33d4cb2092f630a29e893e096a02)
@@ -37,5 +37,5 @@
 #include <io/verify.h>
 
-extern int ddf_log_init(const char *);
+extern errno_t ddf_log_init(const char *);
 extern void ddf_msg(log_level_t, const char *, ...)
     PRINTF_ATTRIBUTE(2, 3);