See https://github.com/mathias-arm/sdio-driver and https://github.com/mathias-arm/mbed-os-sdio-glue

Dependents:   mbed-os-example-filesystem-sdio

Revision:
0:d90c6c9a7600
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sdio.cpp	Wed Nov 11 03:05:14 2020 +0000
@@ -0,0 +1,16 @@
+#if COMPONENT_SDIO
+#include "sdio.h"
+
+static SDIOBlockDevice bd;
+
+BlockDevice *BlockDevice::get_default_instance()
+{
+    return &bd;
+}
+
+BlockDevice *get_other_blockdevice()
+{
+    return &bd;
+}
+
+#endif