diff --git a/src/nv_driver.c b/src/nv_driver.c
index 99b2990..070ec4c 100644
--- a/src/nv_driver.c
+++ b/src/nv_driver.c
@@ -1295,7 +1295,7 @@ nvProbeDDC(ScrnInfoPtr pScrn, int index)
 
 Bool NVI2CInit(ScrnInfoPtr pScrn)
 {
-    char *mod = "i2c";
+    const char *mod = "i2c";
 
     if (xf86LoadSubModule(pScrn, mod)) {
 
diff --git a/src/riva_driver.c b/src/riva_driver.c
index 501266f..232568c 100644
--- a/src/riva_driver.c
+++ b/src/riva_driver.c
@@ -316,7 +316,7 @@ rivaProbeDDC(ScrnInfoPtr pScrn, int index)
 
 Bool RivaI2CInit(ScrnInfoPtr pScrn)
 {
-    char *mod = "i2c";
+    const char *mod = "i2c";
 
     if (xf86LoadSubModule(pScrn, mod)) {