uhd: Add reference power level API to multi_usrp and radio_control

This adds the following API calls:

- multi_usrp::has_{rx,tx}_power_reference()
- multi_usrp::set_{rx,tx}_power_reference()
- multi_usrp::get_{rx,tx}_power_reference()
- radio_control::has_{rx,tx}_power_reference()
- radio_control::set_{rx,tx}_power_reference()
- radio_control::get_{rx,tx}_power_reference()

It also adds a manual page explaining the philosophy of the API.

Note that this does not actually add this feature to any device
implementation. Calling the new API calls will thus result in
`uhd::not_implemented_error` exceptions being thrown. This commit is to
lock down the API and ABI.

1 files changed, 36 insertions, 0 deletions

diff --git a/host/lib/usrp/multi_usrp_rfnoc.cpp b/host/lib/usrp/multi_usrp_rfnoc.cpp
index 14b5fd50b..a62fe3f8e 100644
--- a/host/lib/usrp/multi_usrp_rfnoc.cpp
+++ b/host/lib/usrp/multi_usrp_rfnoc.cpp
@@ -1396,6 +1396,24 @@ public:
         return rx_chain.radio->get_rx_gain_names(rx_chain.block_chan);
     }
 
+    bool has_rx_power_reference(const size_t chan)
+    {
+        auto& rx_chain = _get_rx_chan(chan);
+        return rx_chain.radio->has_rx_power_reference(rx_chain.block_chan);
+    }
+
+    void set_rx_power_reference(const double power_dbm, const size_t chan)
+    {
+        auto& rx_chain = _get_rx_chan(chan);
+        rx_chain.radio->set_rx_power_reference(power_dbm, rx_chain.block_chan);
+    }
+
+    double get_rx_power_reference(const size_t chan)
+    {
+        auto& rx_chain = _get_rx_chan(chan);
+        return rx_chain.radio->get_rx_power_reference(rx_chain.block_chan);
+    }
+
     void set_rx_antenna(const std::string& ant, size_t chan)
     {
         auto& rx_chain = _get_rx_chan(chan);
@@ -1836,6 +1854,24 @@ public:
         return tx_chain.radio->get_tx_gain_names(tx_chain.block_chan);
     }
 
+    bool has_tx_power_reference(const size_t chan)
+    {
+        auto& tx_chain = _get_tx_chan(chan);
+        return tx_chain.radio->has_rx_power_reference(tx_chain.block_chan);
+    }
+
+    void set_tx_power_reference(const double power_dbm, const size_t chan)
+    {
+        auto& tx_chain = _get_tx_chan(chan);
+        tx_chain.radio->set_tx_power_reference(power_dbm, tx_chain.block_chan);
+    }
+
+    double get_tx_power_reference(const size_t chan)
+    {
+        auto& tx_chain = _get_tx_chan(chan);
+        return tx_chain.radio->get_tx_power_reference(tx_chain.block_chan);
+    }
+
     void set_tx_antenna(const std::string& ant, size_t chan)
     {
         auto tx_chain = _get_tx_chan(chan);