diff --git a/src/drivers/intel/gma/acpi/common.asl b/src/drivers/intel/gma/acpi/common.asl
index 79960e1586..254a66d605 100644
--- a/src/drivers/intel/gma/acpi/common.asl
+++ b/src/drivers/intel/gma/acpi/common.asl
@@ -42,7 +42,7 @@
 			{
 				Decrement (Local0)
 			}
-			XBCM (DerefOf (Index (BRIG, Local0)))
+			XBCM (DerefOf (BRIG[Local0]))
 		}
 	}
 
@@ -60,6 +60,6 @@
 			{
 				Increment (Local0)
 			}
-			XBCM (DerefOf (Index (BRIG, Local0)))
+			XBCM (DerefOf (BRIG[Local0]))
 		}
 	}
diff --git a/src/drivers/intel/gma/acpi/configure_brightness_levels.asl b/src/drivers/intel/gma/acpi/configure_brightness_levels.asl
index 0ab93d803a..92ae766661 100644
--- a/src/drivers/intel/gma/acpi/configure_brightness_levels.asl
+++ b/src/drivers/intel/gma/acpi/configure_brightness_levels.asl
@@ -123,8 +123,8 @@
 			Store (2, Local1)
 			While (LLess (Local1, Subtract (SizeOf (BRIG), 1))) {
 				/* Local[23]: adjacent values in BRIG */
-				Store (DeRefOf (Index (BRIG, Local1)), Local2)
-				Store (DeRefOf (Index (BRIG, Add (Local1, 1))), Local3)
+				Store (DeRefOf (BRIG[Local1]), Local2)
+				Store (DeRefOf (BRIG[Add (Local1, 1)]), Local3)
 
 				If (LLess (Local0, Local3)) {
 					If (LOr (LLess (Local0, Local2),