diff --git a/features/mbedtls/platform/TARGET_PSA/COMPONENT_PSA_SRV_IMPL/src/default_random_seed.cpp b/features/mbedtls/platform/TARGET_PSA/COMPONENT_PSA_SRV_IMPL/src/default_random_seed.cpp
index 64a6431697..d7c85ac6d6 100644
--- a/features/mbedtls/platform/TARGET_PSA/COMPONENT_PSA_SRV_IMPL/src/default_random_seed.cpp
+++ b/features/mbedtls/platform/TARGET_PSA/COMPONENT_PSA_SRV_IMPL/src/default_random_seed.cpp
@@ -5,6 +5,10 @@
 
 int mbed_default_seed_read(unsigned char *buf, size_t buf_len)
 {
+    /* Make sure that in case of an error the value will be negative
+     * return (-1 * rc);
+     * Mbed TLS errors are negative values
+     */
     psa_its_status_t rc = psa_its_get(PSA_CRYPTO_ITS_RANDOM_SEED_UID, 0, buf_len, buf);
     return ( -1 * rc );
 }
@@ -12,6 +16,10 @@ int mbed_default_seed_read(unsigned char *buf, size_t buf_len)
 int mbed_default_seed_write(unsigned char *buf, size_t buf_len)
 {
     psa_its_status_t rc = psa_its_set(PSA_CRYPTO_ITS_RANDOM_SEED_UID, buf_len, buf, 0);
+    /* Make sure that in case of an error the value will be negative
+     * return (-1 * rc);
+     * Mbed TLS errors are negative values
+     */
     return ( -1 * rc );
 }