diff --git a/arch/mips/include/asm/cdmm.h b/arch/mips/include/asm/cdmm.h
index c06dbf8ba937..81fa99084178 100644
--- a/arch/mips/include/asm/cdmm.h
+++ b/arch/mips/include/asm/cdmm.h
@@ -63,7 +63,7 @@ struct mips_cdmm_driver {
  */
 phys_addr_t mips_cdmm_phys_base(void);
 
-extern struct bus_type mips_cdmm_bustype;
+extern const struct bus_type mips_cdmm_bustype;
 void __iomem *mips_cdmm_early_probe(unsigned int dev_type);
 
 #define to_mips_cdmm_device(d)	container_of(d, struct mips_cdmm_device, dev)
diff --git a/drivers/bus/mips_cdmm.c b/drivers/bus/mips_cdmm.c
index 554e1992edd4..8baf14bd5eff 100644
--- a/drivers/bus/mips_cdmm.c
+++ b/drivers/bus/mips_cdmm.c
@@ -118,7 +118,7 @@ static struct attribute *mips_cdmm_dev_attrs[] = {
 };
 ATTRIBUTE_GROUPS(mips_cdmm_dev);
 
-struct bus_type mips_cdmm_bustype = {
+const struct bus_type mips_cdmm_bustype = {
 	.name		= "cdmm",
 	.dev_groups	= mips_cdmm_dev_groups,
 	.match		= mips_cdmm_match,