Target only USB ledger with interface number 0

src/lib_signer_backends/ledger.ml

@@ -304,6 +304,12 @@ let find_ledgers ?id () =
   log_info "Found %d Ledger(s)" (List.length ledgers) ;
   filter_map_s begin fun device_info ->
     log_info "Processing Ledger at path [%s]" device_info.Hidapi.path ;
+    if device_info.Hidapi.interface_number <> 0
+    then
+      (* HID interfaces get number 0:
+         https://github.com/LedgerHQ/ledger-nano-s/issues/48 *)
+      return_none
+    else
       match Hidapi.(open_path device_info.path) with
       | None -> return_none
       | Some h ->