add tx gain

AudioOutput.cpp

@@ -90,6 +90,8 @@ HifiBerryAudioOutputput::HifiBerryAudioOutputput(int pcmrate, SoapyHifiBerryData
 	parameters.nChannels = 2;
 	parameters.firstChannel = 0;
 	parameters.deviceId = 0;
+	DigitalPlaybackMin = 0;
+	DigitalPlaybackMax = 100;
 }
 
 /*
@@ -123,6 +125,7 @@ bool HifiBerryAudioOutputput::open(std::string device)
 		printf("Cannot open audio output stream\n");
 		return false;
 	}
+	get_alsa_range(1, "Digital Playback Volume");
 	this->startStream();
 	return true;	
 }
@@ -251,6 +254,49 @@ int HifiBerryAudioOutputput::controle_alsa(int element, int ivalue)
 	return 0;
 }
 
+int HifiBerryAudioOutputput::get_alsa_range(int element, std::string name)
+{
+	char str[80];
+	snd_ctl_t *ctl;
+	snd_ctl_elem_id_t *id;
+	snd_ctl_elem_info_t *info;
+	snd_ctl_elem_value_t *control;
+	int err;
+
+	snd_ctl_elem_id_alloca(&id);
+	snd_ctl_elem_info_alloca(&info);
+	snd_ctl_elem_value_alloca(&control);
+
+	// Open the control interface for the specified sound card
+	sprintf(str, "hw:%d", alsa_device);
+	if ((err = snd_ctl_open(&ctl, str, 0)) < 0)
+	{
+		printf("Error opening control interface: %s\n", snd_strerror(err));
+		return err;
+	}
+
+	// Set the ID of the element we want to retrieve information for
+	snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_MIXER);
+	snd_ctl_elem_id_set_name(id, name.c_str());
+
+	// Retrieve the element information
+	snd_ctl_elem_info_set_id(info, id);
+	if ((err = snd_ctl_elem_info(ctl, info)) < 0)
+	{
+		printf("Error retrieving element info: %s\n", snd_strerror(err));
+		snd_ctl_close(ctl);
+		return err;
+	}
+
+	// Retrieve the element range
+	DigitalPlaybackMin = snd_ctl_elem_info_get_min(info);
+	DigitalPlaybackMax = snd_ctl_elem_info_get_max(info);
+	printf("Digital Playback Volume range: [%ld, %ld]\n", DigitalPlaybackMin, DigitalPlaybackMax);
+
+	snd_ctl_close(ctl);
+	return 0;
+}
+
 /*
 pi@pi3:~$ amixer --debug - c 3 controls
 numid = 22, iface = MIXER, name = 'Headphone Playback Volume'

AudioOutput.h

@@ -37,6 +37,8 @@ class HifiBerryAudioOutputput :
   unsigned int get_device() { return parameters.deviceId;}
   int controle_alsa(int element, int ivalue);
   int lookup_id(snd_ctl_elem_id_t *id, snd_ctl_t *handle);
+  int get_alsa_range(int element, std::string name);
+  int get_max_volume() { return DigitalPlaybackMax; }
 
 protected:
 	void samplesToInt16(const SampleVector& samples,
@@ -53,4 +55,5 @@ class HifiBerryAudioOutputput :
 	atomic<int>					underrun;
 	int alsa_device;
 	map<int, std::string> device_map;
+	long DigitalPlaybackMin, DigitalPlaybackMax;
 };

SoapyHifiBerrySettings.cpp

@@ -5,7 +5,7 @@
  * Device interface
  **********************************************************************/
 const cfg::File::ConfigMap defaultOptions = {
-	{"si5351", {{"correction", cfg::makeOption("0")}, {"rxdrive", cfg::makeOption("2")}, {"txdrive", cfg::makeOption("2")}}},
+	{"si5351", {{"correction", cfg::makeOption("0")}, {"rxdrive", cfg::makeOption("2")}, {"t.xdrive", cfg::makeOption("2")}}},
 	{"sound", {{"device", cfg::makeOption("snd_rpi_hifiberry_dacplusadcpro")}, {"samplerate", cfg::makeOption("192000")}}}
 };
 
@@ -267,12 +267,25 @@ SoapySDR::Range SoapyHifiBerry::getGainRange(const int direction, const size_t c
 
 void SoapyHifiBerry::setGain(const int direction, const size_t channel, const double value)
 {
-
-	SoapySDR_log(SOAPY_SDR_INFO, "SoapyHifiBerry::setGain called");
+	char str[80];
+	sprintf(str, "SoapyHifiBerry::setGain called %f", value * 2.4);
+	SoapySDR_log(SOAPY_SDR_INFO, str);
 
 	if (direction == SOAPY_SDR_RX)
 		uptr_HifiBerryAudioOutputput->controle_alsa(21, (int) value); // numid = 21, iface = MIXER, name = 'ADC Capture Volume'
 
+	if (direction == SOAPY_SDR_TX)
+	{
+		if (value < 99.9)
+		{
+			float factor = uptr_HifiBerryAudioOutputput->get_max_volume() / 100.0;
+			uptr_HifiBerryAudioOutputput->controle_alsa(1, (int)(value * factor)); //numid = 1, iface = MIXER, name = 'Digital Playback Volume'
+		}
+		else
+		{
+			uptr_HifiBerryAudioOutputput->controle_alsa(1, uptr_HifiBerryAudioOutputput->get_max_volume()); //numid = 1, iface = MIXER, name = 'Digital Playback Volume'
+		}
+	}
 }
 
 /*******************************************************************