mpmd: Provide list of MPM devices to fail fast on find

With this fix, uhd_find_devices --args type=b200, for example, will not
stall in this function.

Reviewed-by: Ashish Chaudhari <ashish.chaudhari@ettus.com>
Reviewed-by: Brent Stapleton  <brent.stapleton@ettus.com>

2 files changed, 34 insertions, 1 deletions

diff --git a/host/lib/usrp/mpmd/mpmd_devices.hpp b/host/lib/usrp/mpmd/mpmd_devices.hpp
new file mode 100644
index 000000000..7e12fe31a
--- /dev/null
+++ b/host/lib/usrp/mpmd/mpmd_devices.hpp
@@ -0,0 +1,23 @@
+//
+// Copyright 2018 Ettus Research, a National Instruments Company
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+
+
+#ifndef INCLUDED_MPMD_DEVICES_HPP
+#define INCLUDED_MPMD_DEVICES_HPP
+
+#include <vector>
+#include <string>
+
+static constexpr char MPM_CATCHALL_DEVICE_TYPE[] = "mpm";
+
+// List all MPM devices here by their 'type' key. Note: Do not use these values
+// to make decisions. This vector is for filtering purposes.
+static const std::vector<std::string> MPM_DEVICE_TYPES = {
+    MPM_CATCHALL_DEVICE_TYPE,
+    "n3xx"
+};
+
+#endif /* INCLUDED_MPMD_DEVICES_HPP */
diff --git a/host/lib/usrp/mpmd/mpmd_find.cpp b/host/lib/usrp/mpmd/mpmd_find.cpp
index 8e0bada43..b2471d30c 100644
--- a/host/lib/usrp/mpmd/mpmd_find.cpp
+++ b/host/lib/usrp/mpmd/mpmd_find.cpp
@@ -7,6 +7,7 @@
 // find-related code for MPM devices
 
 #include "mpmd_impl.hpp"
+#include "mpmd_devices.hpp"
 #include <uhd/types/device_addr.hpp>
 #include <uhd/transport/udp_simple.hpp>
 #include <uhd/transport/if_addrs.hpp>
@@ -116,7 +117,7 @@ device_addrs_t mpmd_find_with_addr(
         if (
             (not hint_.has_key("name")        or hint_["name"]    == new_addr["name"])
             and (not hint_.has_key("serial")  or hint_["serial"]  == new_addr["serial"])
-            and (not hint_.has_key("type")    or hint_["type"]    == new_addr["type"])
+            and (not hint_.has_key("type")    or hint_["type"]    == new_addr["type"] or hint_["type"] == MPM_CATCHALL_DEVICE_TYPE)
             and (not hint_.has_key("product") or hint_["product"] == new_addr["product"])
         ){
             UHD_LOG_TRACE("MPMD FIND",
@@ -201,6 +202,15 @@ device_addrs_t mpmd_find_with_bcast(const device_addr_t& hint)
 device_addrs_t mpmd_find(const device_addr_t& hint_)
 {
     device_addrs_t hints = separate_device_addr(hint_);
+    if (hint_.has_key("type")) {
+        if (std::find(MPM_DEVICE_TYPES.cbegin(),
+                      MPM_DEVICE_TYPES.cend(),
+                      hint_["type"]) == MPM_DEVICE_TYPES.cend()) {
+            UHD_LOG_TRACE("MPMD FIND",
+                "Returning early, type does not match an MPM device.");
+            return {};
+        }
+    }
     UHD_LOG_TRACE("MPMD FIND",
         "Finding with " << hints.size() << " different hint(s).");