ad9361: Minor clarifications on req_rate and baseband_bw

2 files changed, 13 insertions, 4 deletions

diff --git a/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp b/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp
index e3139cd39..413ec75a2 100644
--- a/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp
+++ b/host/lib/usrp/common/ad9361_driver/ad9361_device.cpp
@@ -1247,7 +1247,7 @@ double ad9361_device_t::_setup_rates(const double rate)
     /* If we make it into this function, then we are tuning to a new rate.
      * Store the new rate. */
     _req_clock_rate = rate;
-    UHD_LOG << boost::format("[ad9361_device_t::_setup_rates] rate=%d\n") % rate;
+    UHD_LOG << boost::format("[ad9361_device_t::_setup_rates] rate=%.6d\n") % rate;
 
     /* Set the decimation and interpolation values in the RX and TX chains.
      * This also switches filters in / out. Note that all transmitters and
@@ -1629,7 +1629,9 @@ double ad9361_device_t::set_clock_rate(const double req_rate)
      * starts up. This prevents that, and any bugs in user code that request
      * the same rate over and over. */
     if (freq_is_nearly_equal(req_rate, _req_clock_rate)) {
-        return _baseband_bw; // IJB. Should this not return req_rate?
+        // We return _baseband_bw, because that's closest to the
+        // actual value we're currently running.
+        return _baseband_bw;
     }
 
     /* We must be in the SLEEP / WAIT state to do this. If we aren't already
diff --git a/host/lib/usrp/common/ad9361_driver/ad9361_device.h b/host/lib/usrp/common/ad9361_driver/ad9361_device.h
index bd4ad368f..a42c5ac9a 100644
--- a/host/lib/usrp/common/ad9361_driver/ad9361_device.h
+++ b/host/lib/usrp/common/ad9361_driver/ad9361_device.h
@@ -112,8 +112,15 @@ private:    //Members
     ad9361_io::sptr     _io_iface;
     //Intermediate state
     double              _rx_freq, _tx_freq, _req_rx_freq, _req_tx_freq;
-    double              _baseband_bw, _bbpll_freq, _adcclock_freq;
-    double              _req_clock_rate, _req_coreclk;
+    //! Current baseband sampling rate (this is the actual rate the device is
+    //  is running at)
+    double              _baseband_bw;
+    double              _bbpll_freq, _adcclock_freq;
+    //! This was the last clock rate value that was requested.
+    //  It is cached so we don't need to re-set the clock rate
+    //  if another call to set_clock_rate() actually has the same value.
+    double              _req_clock_rate;
+    double              _req_coreclk;
     boost::uint16_t     _rx_bbf_tunediv;
     boost::uint8_t      _curr_gain_table;
     double              _rx1_gain, _rx2_gain, _tx1_gain, _tx2_gain;