diff --git a/drivers/mfd/mc13xxx-spi.c b/drivers/mfd/mc13xxx-spi.c
index c973e2579bdf..9f438d5d4326 100644
--- a/drivers/mfd/mc13xxx-spi.c
+++ b/drivers/mfd/mc13xxx-spi.c
@@ -116,7 +116,7 @@ static int mc13xxx_spi_write(void *context, const void *data, size_t count)
  * single transfer.
  */
 
-static struct regmap_bus regmap_mc13xxx_bus = {
+static const struct regmap_bus regmap_mc13xxx_bus = {
 	.write = mc13xxx_spi_write,
 	.read = mc13xxx_spi_read,
 };