diff --git a/drivers/gpu/drm/ast/ast_dp501.c b/drivers/gpu/drm/ast/ast_dp501.c
index 9e19d8c17730..677c52c0d99a 100644
--- a/drivers/gpu/drm/ast/ast_dp501.c
+++ b/drivers/gpu/drm/ast/ast_dp501.c
@@ -436,7 +436,7 @@ static void ast_init_analog(struct ast_device *ast)
 	/* Finally, clear bits [17:16] of SCU2c */
 	data = ast_read32(ast, 0x1202c);
 	data &= 0xfffcffff;
-	ast_write32(ast, 0, data);
+	ast_write32(ast, 0x1202c, data);
 
 	/* Disable DVO */
 	ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xa3, 0xcf, 0x00);