filter API: Fix Python bindings and multi_usrp calls

This fixes the following issues:
- The Python bindings did not declare parents for the various filter
  object classes properly. This meant that set_?x_filter wouldn't work,
  because the user would pass a specific type (e.g., analog_filter_lp),
  but the class would not recognize it as a filter_info_base.
- In multi_usrp.cpp, filter names are also property tree paths to make
  them unique. However, the setters and getters for filters would then
  prepend the FE path again, thus breaking those calls.

2 files changed, 5 insertions, 6 deletions

diff --git a/host/lib/types/filters_python.hpp b/host/lib/types/filters_python.hpp
index 76b2c3a49..7210faa21 100644
--- a/host/lib/types/filters_python.hpp
+++ b/host/lib/types/filters_python.hpp
@@ -31,13 +31,14 @@ void export_filters(py::module& m)
         .def("get_type", &filter_info_base::get_type)
         .def("__str__", &filter_info_base::to_pp_string);
 
-    py::class_<analog_filter_base, analog_filter_base::sptr>(m, "analog_filter_base")
+    py::class_<analog_filter_base, filter_info_base, analog_filter_base::sptr>(
+        m, "analog_filter_base")
         .def(py::init<filter_info_type, bool, size_t, std::string>())
 
         // Methods
         .def("get_analog_type", &analog_filter_base::get_analog_type);
 
-    py::class_<analog_filter_lp, std::shared_ptr<analog_filter_lp>>(m, "analog_filter_lp")
+    py::class_<analog_filter_lp, analog_filter_base, std::shared_ptr<analog_filter_lp>>(m, "analog_filter_lp")
         .def(
             py::init<filter_info_type, bool, size_t, const std::string, double, double>())
 
diff --git a/host/lib/usrp/multi_usrp.cpp b/host/lib/usrp/multi_usrp.cpp
index c41b31083..04d054b60 100644
--- a/host/lib/usrp/multi_usrp.cpp
+++ b/host/lib/usrp/multi_usrp.cpp
@@ -1905,8 +1905,7 @@ public:
             throw uhd::runtime_error("Attempting to get non-existing filter: " + name);
         }
 
-        return _tree->access<filter_info_base::sptr>(rx_rf_fe_root(chan) / name / "value")
-            .get();
+        return _tree->access<filter_info_base::sptr>(fs_path(name) / "value").get();
     }
 
     void set_rx_filter(
@@ -1919,8 +1918,7 @@ public:
             throw uhd::runtime_error("Attempting to set non-existing filter: " + name);
         }
 
-        _tree->access<filter_info_base::sptr>(rx_rf_fe_root(chan) / name / "value")
-            .set(filter);
+        _tree->access<filter_info_base::sptr>(fs_path(name) / "value").set(filter);
     }
 
     std::vector<std::string> get_tx_filter_names(const size_t chan)