diff --git a/crypto/random_pool.c b/crypto/random_pool.c
index bdae9d506f..ace8ca7442 100644
--- a/crypto/random_pool.c
+++ b/crypto/random_pool.c
@@ -111,7 +111,8 @@ static struct rng_s g_rng;
 #ifdef CONFIG_BOARD_ENTROPY_POOL
 /* Entropy pool structure can be provided by board source. Use for this is,
  * for example, allocate entropy pool from special area of RAM which content
- * is kept over system reset. */
+ * is kept over system reset.
+ */
 
 #  define entropy_pool board_entropy_pool
 #else
diff --git a/drivers/crypto/dev_urandom.c b/drivers/crypto/dev_urandom.c
index 77778e70d5..6ac260a3d4 100644
--- a/drivers/crypto/dev_urandom.c
+++ b/drivers/crypto/dev_urandom.c
@@ -162,14 +162,15 @@ static inline uint32_t do_congruential(void)
 static ssize_t devurand_read(FAR struct file *filep, FAR char *buffer,
                              size_t len)
 {
+  size_t n;
+  uint32_t rnd;
+
 #ifdef CONFIG_DEV_URANDOM_RANDOM_POOL
-  if (len)
+  if (len > 0)
     {
       getrandom(buffer, len);
     }
 #else
-  size_t n;
-  uint32_t rnd;
 
   n = len;
 
@@ -239,6 +240,7 @@ static ssize_t devurand_write(FAR struct file *filep, FAR const char *buffer,
   memcpy(&seed, buffer, len);
   srand(seed);
   return len;
+
 #elif defined(CONFIG_DEV_URANDOM_RANDOM_POOL)
   const unsigned int alignmask = sizeof(uint32_t) - 1;
   const size_t initlen = len;