psa_util: update documentation for mbedtls_ecdsa_der_to_raw()
Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/include/mbedtls/psa_util.h b/include/mbedtls/psa_util.h
index 132c73f..8868bc1 100644
--- a/include/mbedtls/psa_util.h
+++ b/include/mbedtls/psa_util.h
@@ -211,7 +211,8 @@
* \param der_len Size of \p der in bytes.
* \param[out] raw Buffer that will be filled with the converted raw
* signature. It can overlap with der buffer.
- * \param raw_size Size of \p raw in bytes.
+ * \param raw_size Size of \p raw in bytes. Must be at least
+ * 2 * PSA_BITS_TO_BYTES(bits) bytes.
* \param[out] raw_len On success it is updated with the amount of valid
* data (in bytes) written to \p raw. It's undefined
* in case of failure.