diff --git a/arch/arm/src/sama5/sam_trng.c b/arch/arm/src/sama5/sam_trng.c
index 089c9f248ef..9f9cec8e55b 100644
--- a/arch/arm/src/sama5/sam_trng.c
+++ b/arch/arm/src/sama5/sam_trng.c
@@ -400,7 +400,7 @@ static int sam_rng_initialize(void)
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_RANDOM
-int devrandom_register(void)
+void devrandom_register(void)
 {
   int ret;
 
@@ -413,8 +413,6 @@ int devrandom_register(void)
           ferr("ERROR: Failed to register /dev/random\n");
         }
     }
-
-  return ret;
 }
 #endif
 
@@ -424,10 +422,16 @@ int devrandom_register(void)
  * Description:
  *   Register /dev/urandom
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_URANDOM_ARCH
-int devurandom_register(void)
+void devurandom_register(void)
 {
   int ret;
 
@@ -442,8 +446,6 @@ int devurandom_register(void)
           ferr("ERROR: Failed to register /dev/urandom\n");
         }
     }
-
-  return ret;
 }
 #endif
 
diff --git a/arch/arm/src/samv7/sam_trng.c b/arch/arm/src/samv7/sam_trng.c
index d9951cace36..1634cc46f35 100644
--- a/arch/arm/src/samv7/sam_trng.c
+++ b/arch/arm/src/samv7/sam_trng.c
@@ -401,7 +401,7 @@ static int sam_rng_initialize(void)
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_RANDOM
-int devrandom_register(void)
+void devrandom_register(void)
 {
   int ret;
 
@@ -414,8 +414,6 @@ int devrandom_register(void)
           ferr("ERROR: Failed to register /dev/random\n");
         }
     }
-
-  return ret;
 }
 #endif
 
@@ -425,10 +423,16 @@ int devrandom_register(void)
  * Description:
  *   Register /dev/urandom
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_URANDOM_ARCH
-int devurandom_register(void)
+void devurandom_register(void)
 {
   int ret;
 
@@ -443,8 +447,6 @@ int devurandom_register(void)
           ferr("ERROR: Failed to register /dev/urandom\n");
         }
     }
-
-  return ret;
 }
 #endif
 
diff --git a/arch/arm/src/stm32/stm32_rng.c b/arch/arm/src/stm32/stm32_rng.c
index 57743d157d6..2cc1e6409ca 100644
--- a/arch/arm/src/stm32/stm32_rng.c
+++ b/arch/arm/src/stm32/stm32_rng.c
@@ -277,10 +277,10 @@ static ssize_t stm32_read(struct file *filep, char *buffer, size_t buflen)
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_RANDOM
-int devrandom_register(void)
+void devrandom_register(void)
 {
   stm32_rng_initialize();
-  return register_driver("/dev/random", &g_rngops, 0444, NULL);
+  (void)register_driver("/dev/random", &g_rngops, 0444, NULL);
 }
 #endif
 
@@ -290,15 +290,21 @@ int devrandom_register(void)
  * Description:
  *   Register /dev/urandom
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_URANDOM_ARCH
-int devurandom_register(void)
+void devurandom_register(void)
 {
 #ifndef CONFIG_DEV_RANDOM
   stm32l4_rnginitialize();
 #endif
-  return register_driver("/dev/urandom", &g_rngops, 0444, NULL);
+  (void)register_driver("/dev/urandom", &g_rngops, 0444, NULL);
 }
 #endif
 
diff --git a/arch/arm/src/stm32l4/stm32l4_rng.c b/arch/arm/src/stm32l4/stm32l4_rng.c
index 64f08dc04b4..e048edda167 100644
--- a/arch/arm/src/stm32l4/stm32l4_rng.c
+++ b/arch/arm/src/stm32l4/stm32l4_rng.c
@@ -306,10 +306,10 @@ static ssize_t stm32l4_rngread(struct file *filep, char *buffer, size_t buflen)
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_RANDOM
-int devrandom_register(void)
+void devrandom_register(void)
 {
   stm32l4_rng_initialize();
-  return register_driver("/dev/random", &g_rngops, 0444, NULL);
+  (void)register_driver("/dev/random", &g_rngops, 0444, NULL);
 }
 #endif
 
@@ -319,15 +319,21 @@ int devrandom_register(void)
  * Description:
  *   Register /dev/urandom
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_URANDOM_ARCH
-int devurandom_register(void)
+void devurandom_register(void)
 {
 #ifndef CONFIG_DEV_RANDOM
   stm32l4_rng_initialize();
 #endif
-  return register_driver("/dev/urandom", &g_rngops, 0444, NULL);
+  (void)register_driver("/dev/urandom", &g_rngops, 0444, NULL);
 }
 #endif
 
diff --git a/include/nuttx/fs/fs.h b/include/nuttx/fs/fs.h
index b9866adaad4..ef99ff6f51b 100644
--- a/include/nuttx/fs/fs.h
+++ b/include/nuttx/fs/fs.h
@@ -1009,6 +1009,12 @@ int fdesc_poll(int fd, FAR struct pollfd *fds, bool setup);
  * Description:
  *   Register /dev/null
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 void devnull_register(void);
@@ -1019,6 +1025,12 @@ void devnull_register(void);
  * Description:
  *   Initialize the RNG hardware and register the /dev/random driver.
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_RANDOM
@@ -1031,6 +1043,12 @@ void devrandom_register(void);
  * Description:
  *   Register /dev/urandom
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 #ifdef CONFIG_DEV_URANDOM
@@ -1043,6 +1061,12 @@ void devurandom_register(void);
  * Description:
  *   Register /dev/crypto
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 void devcrypto_register(void);
@@ -1053,6 +1077,12 @@ void devcrypto_register(void);
  * Description:
  *   Register /dev/zero
  *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   None
+ *
  ****************************************************************************/
 
 void devzero_register(void);