diff --git a/src/acecad.c b/src/acecad.c
index 1c0b4f7..c146105 100644
--- a/src/acecad.c
+++ b/src/acecad.c
@@ -185,7 +185,7 @@ IsUSBLine(int fd)
     }
 }
 
-/* Heavily inspired by synpatics/eventcomm.c */
+/* Heavily inspired by synaptics/eventcomm.c */
 
 #define DEV_INPUT_EVENT "/dev/input/event"
 #define EV_DEV_NAME_MAXLEN 64
@@ -196,8 +196,8 @@ static Bool
 fd_query_acecad(int fd, char *ace_name) {
     char name[256] = "Unknown";
     int cmp_at = strlen(ace_name);
-    if (cmp_at > 256)
-        cmp_at = 256;
+    if (cmp_at > 255)
+        cmp_at = 255;
     ioctl(fd, EVIOCGNAME(sizeof(name)), name);
     name[cmp_at] = '\0';
     if (xf86NameCmp(name, ace_name) == 0)