Improve LO APIs for daughterboards without configurable LOs

2 files changed, 18 insertions, 5 deletions

diff --git a/host/include/uhd/usrp/multi_usrp.hpp b/host/include/uhd/usrp/multi_usrp.hpp
index ab757be8a..d09b5bb15 100644
--- a/host/include/uhd/usrp/multi_usrp.hpp
+++ b/host/include/uhd/usrp/multi_usrp.hpp
@@ -510,6 +510,8 @@ public:
 
     /*!
      * Get the currently set LO source.
+     * Channels without controllable LO sources will return
+     * "internal"
      * \param name the name of the LO stage to query
      * \param chan the channel index 0 to N-1
      * \return the configured LO source
@@ -518,6 +520,8 @@ public:
 
     /*!
      * Get a list of possible LO sources.
+     * Channels which do not have controllable LO sources
+     * will return "internal".
      * \param name the name of the LO stage to query
      * \param chan the channel index 0 to N-1
      * \return a vector of strings for possible settings
@@ -552,6 +556,8 @@ public:
 
     /*!
      * Get the current RX LO frequency (Advanced).
+     * If the channel does not have independently configurable LOs
+     * the current rf frequency will be returned.
      * \param name the name of the LO stage to query
      * \param chan the channel index 0 to N-1
      * \return the configured LO frequency
@@ -560,6 +566,8 @@ public:
 
     /*!
      * Get the LO frequency range of the RX LO.
+     * If the channel does not have independently configurable LOs
+     * the rf frequency range will be returned.
      * \param name the name of the LO stage to query
      * \param chan the channel index 0 to N-1
      * \return a frequency range object
diff --git a/host/lib/usrp/multi_usrp.cpp b/host/lib/usrp/multi_usrp.cpp
index b5df54a65..0c3c78fc6 100644
--- a/host/lib/usrp/multi_usrp.cpp
+++ b/host/lib/usrp/multi_usrp.cpp
@@ -897,7 +897,8 @@ public:
                 }
             }
         } else {
-            throw uhd::runtime_error("This device does not support manual configuration of LOs");
+            // If the daughterboard doesn't expose it's LO(s) then it can only be internal
+            return "internal";
         }
     }
 
@@ -918,7 +919,8 @@ public:
                 }
             }
         } else {
-            throw uhd::runtime_error("This device does not support manual configuration of LOs");
+            // If the daughterboard doesn't expose it's LO(s) then it can only be internal
+            return std::vector<std::string> {1, "internal"};
         }
     }
 
@@ -958,7 +960,8 @@ public:
                 }
             }
         } else {
-            throw uhd::runtime_error("This device does not support manual configuration of LOs");
+            // If the daughterboard doesn't expose it's LO(s), assume it cannot export
+            return false;
         }
     }
 
@@ -991,7 +994,8 @@ public:
                 }
             }
         } else {
-            throw uhd::runtime_error("This device does not support manual configuration of LOs");
+            // Return actual RF frequency if the daughterboard doesn't expose it's LO(s)
+            return _tree->access<double>(rx_rf_fe_root(chan) / "freq" /" value").get();
         }
     }
 
@@ -1007,7 +1011,8 @@ public:
                 }
             }
         } else {
-            throw uhd::runtime_error("This device does not support manual configuration of LOs");
+            // Return the actual RF range if the daughterboard doesn't expose it's LO(s)
+            return _tree->access<meta_range_t>(rx_rf_fe_root(chan) / "freq" / "range").get();
         }
     }