Transceiver52M: Update to UHD streamer interface

This patch is long overdue and can now be merged after better understanding
of timestamp stability issues. UHD tick / timespec conversions were
generally used with the streamer interface, though these calls are actually
independent change sets. The combination would lead to internal rounding
errors and a timing drift most notably on B100 running at GSM symbol
rate multiples. There are no known issues, however, with the streamer code
itself.

The aforementioned issue was discovered in test code only, which was never
merged to mainline.

Signed-off-by: Thomas Tsou <tom@tsou.cc>

2 files changed, 16 insertions, 29 deletions

diff --git a/Transceiver52M/UHDDevice.cpp b/Transceiver52M/UHDDevice.cpp
index 6fc0c19..7a8e99c 100644
--- a/Transceiver52M/UHDDevice.cpp
+++ b/Transceiver52M/UHDDevice.cpp
@@ -204,6 +204,8 @@ public:
 
 private:
 	uhd::usrp::multi_usrp::sptr usrp_dev;
+	uhd::tx_streamer::sptr tx_stream;
+	uhd::rx_streamer::sptr rx_stream;
 	enum busType bus;
 
 	double desired_smpl_rt, actual_smpl_rt;
@@ -310,16 +312,8 @@ void uhd_device::init_gains()
 
 void uhd_device::set_ref_clk(bool ext_clk)
 {
-	uhd::clock_config_t clk_cfg;
-
-	clk_cfg.pps_source = uhd::clock_config_t::PPS_SMA;
-
 	if (ext_clk)
-		clk_cfg.ref_source = uhd::clock_config_t::REF_SMA;
-	else
-		clk_cfg.ref_source = uhd::clock_config_t::REF_INT;
-
-	usrp_dev->set_clock_config(clk_cfg);
+		usrp_dev->set_clock_source("external");
 
 	return;
 }
@@ -451,10 +445,14 @@ bool uhd_device::open(const std::string &args)
 #ifdef EXTREF
 	set_ref_clk(true);
 #endif
+	// Create TX and RX streamers
+	uhd::stream_args_t stream_args("sc16");
+	tx_stream = usrp_dev->get_tx_stream(stream_args);
+	rx_stream = usrp_dev->get_rx_stream(stream_args);
 
 	// Number of samples per over-the-wire packet
-	tx_spp = usrp_dev->get_device()->get_max_send_samps_per_packet();
-	rx_spp = usrp_dev->get_device()->get_max_recv_samps_per_packet();
+	tx_spp = tx_stream->get_max_num_samps();
+	rx_spp = rx_stream->get_max_num_samps();
 
 	// Set rates
 	actual_smpl_rt = set_rates(desired_smpl_rt);
@@ -488,14 +486,8 @@ bool uhd_device::flush_recv(size_t num_pkts)
 	timeout = .01;
 
 	for (size_t i = 0; i < num_pkts; i++) {
-		num_smpls = usrp_dev->get_device()->recv(
-					buff,
-					rx_spp,
-					md,
-					uhd::io_type_t::COMPLEX_INT16,
-					uhd::device::RECV_MODE_ONE_PACKET,
-					timeout);
-
+		num_smpls = rx_stream->recv(buff, rx_spp, md,
+					    timeout, true);
 		if (!num_smpls) {
 			switch (md.error_code) {
 			case uhd::rx_metadata_t::ERROR_CODE_TIMEOUT:
@@ -634,13 +626,12 @@ int uhd_device::readSamples(short *buf, int len, bool *overrun,
 
 	// Receive samples from the usrp until we have enough
 	while (rx_smpl_buf->avail_smpls(timestamp) < len) {
-		size_t num_smpls = usrp_dev->get_device()->recv(
+		size_t num_smpls = rx_stream->recv(
 					(void*)pkt_buf,
 					rx_spp,
 					metadata,
-					uhd::io_type_t::COMPLEX_INT16,
-					uhd::device::RECV_MODE_ONE_PACKET);
-
+					0.1,
+					true);
 		rx_pkt_cnt++;
 
 		// Check for errors 
@@ -718,11 +709,7 @@ int uhd_device::writeSamples(short *buf, int len, bool *underrun,
 		}
 	}
 
-	size_t num_smpls = usrp_dev->get_device()->send(buf,
-					len,
-					metadata,
-					uhd::io_type_t::COMPLEX_INT16,
-					uhd::device::SEND_MODE_FULL_BUFF);
+	size_t num_smpls = tx_stream->send(buf, len, metadata);
 
 	if (num_smpls != (unsigned) len) {
 		LOG(ALERT) << "UHD: Device send timed out";
diff --git a/configure.ac b/configure.ac
index 03028c2..1c96f51 100644
--- a/configure.ac
+++ b/configure.ac
@@ -98,7 +98,7 @@ AS_IF([test "x$with_usrp1" = "xyes"], [
 ])
 
 AS_IF([test "x$with_uhd" = "xyes"],[
-    PKG_CHECK_MODULES(UHD, uhd >= 003.002.000)
+    PKG_CHECK_MODULES(UHD, uhd >= 003.004.000)
     AC_DEFINE(USE_UHD, 1, Define to 1 if using UHD)
 ])