Index: uspace/drv/char/ns8250/ns8250.c
===================================================================
--- uspace/drv/char/ns8250/ns8250.c	(revision 071a1ddbcc6bb2b9c6f3c1a3acc865f1f23b5fe0)
+++ uspace/drv/char/ns8250/ns8250.c	(revision dd8ab1cacb307cb1ac01aa4918c789d13e112e56)
@@ -40,4 +40,5 @@
 #include <stdio.h>
 #include <errno.h>
+#include <str_error.h>
 #include <stdbool.h>
 #include <fibril_synch.h>
@@ -887,5 +888,5 @@
 	if (rc != EOK) {
 		ddf_msg(LVL_ERROR, "Failed to enable the interrupt. Error code = "
-		    "%d.", rc);
+		    "%s.", str_error_name(rc));
 		goto fail;
 	}
Index: uspace/drv/char/pl050/pl050.c
===================================================================
--- uspace/drv/char/pl050/pl050.c	(revision 071a1ddbcc6bb2b9c6f3c1a3acc865f1f23b5fe0)
+++ uspace/drv/char/pl050/pl050.c	(revision dd8ab1cacb307cb1ac01aa4918c789d13e112e56)
@@ -217,6 +217,6 @@
 	    res.irqs.irqs[0], pl050_interrupt, &pl050_irq_code, &irq_cap);
 	if (rc != EOK) {
-		ddf_msg(LVL_ERROR, "Failed registering interrupt handler. (%d)",
-		    rc);
+		ddf_msg(LVL_ERROR, "Failed registering interrupt handler. (%s)",
+		    str_error_name(rc));
 		goto error;
 	}
Index: uspace/drv/char/sun4v-con/sun4v-con.c
===================================================================
--- uspace/drv/char/sun4v-con/sun4v-con.c	(revision 071a1ddbcc6bb2b9c6f3c1a3acc865f1f23b5fe0)
+++ uspace/drv/char/sun4v-con/sun4v-con.c	(revision dd8ab1cacb307cb1ac01aa4918c789d13e112e56)
@@ -36,4 +36,5 @@
 #include <ddi.h>
 #include <errno.h>
+#include <str_error.h>
 #include <io/chardev_srv.h>
 #include <stdbool.h>
@@ -92,5 +93,5 @@
 	    (void *) &con->input_buffer);
 	if (rc != EOK) {
-		ddf_msg(LVL_ERROR, "Error mapping memory: %d", rc);
+		ddf_msg(LVL_ERROR, "Error mapping memory: %s", str_error_name(rc));
 		goto error;
 	}
@@ -101,5 +102,5 @@
 	    (void *) &con->output_buffer);
 	if (rc != EOK) {
-		ddf_msg(LVL_ERROR, "Error mapping memory: %d", rc);
+		ddf_msg(LVL_ERROR, "Error mapping memory: %s", str_error_name(rc));
 		return rc;
 	}