ecp: add documentation for compressed points limitations
Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index 0392bd4..e66a9f8 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -804,6 +804,9 @@
* with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a
* specific key type, check the result with mbedtls_pk_can_do().
*
+ * \note For compressed points, see #MBEDTLS_ECP_PF_COMPRESSED for
+ * limitations.
+ *
* \note The key is also checked for correctness.
*
* \return 0 if successful, or a specific PK or PEM error code