diff --git a/sys/dev/drm/amd/display/dc/i2caux/dce80/i2caux_dce80.c b/sys/dev/drm/amd/display/dc/i2caux/dce80/i2caux_dce80.c
@@ -121,7 +121,7 @@
 	if (ddc->hw_info.hw_supported) {
 		enum gpio_ddc_line line = dal_ddc_get_line(ddc);
 
-		if (line < GPIO_DDC_LINE_COUNT) {
+		if (line >= 0 && line < GPIO_DDC_LINE_COUNT) {
 			non_generic = true;
 			engine = i2caux->i2c_hw_engines[line];
 		}