diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 08eff51..ff7654a 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -5313,7 +5313,7 @@
 #if defined(MBEDTLS_PSA_INJECT_ENTROPY)
 #include "mbedtls/entropy_poll.h"
 
-psa_status_t mbedtls_psa_inject_entropy( const unsigned char *seed,
+psa_status_t mbedtls_psa_inject_entropy( const uint8_t *seed,
                                          size_t seed_size )
 {
     if( global_data.initialized )