GreaseWeazle autodetection now works (at least on Linux).

lib/usb/greaseweazle.h

@@ -4,6 +4,8 @@
 #define GREASEWEAZLE_VID 0x1209
 #define GREASEWEAZLE_PID 0x4d69
 
+#define GREASEWEAZLE_ID ((GREASEWEAZLE_VID<<16) | GREASEWEAZLE_PID)
+
 #define EP_OUT 0x02
 #define EP_IN 0x83
 

lib/usb/usb.cc

@@ -1,11 +1,14 @@
 #include "globals.h"
 #include "flags.h"
 #include "usb.h"
+#include "libusbp_config.h"
+#include "libusbp.hpp"
 #include "protocol.h"
 #include "fluxmap.h"
 #include "bytes.h"
 #include "proto.h"
 #include "usbfinder.h"
+#include "greaseweazle.h"
 #include "fmt/format.h"
 
 static USB* usb = NULL;
@@ -13,41 +16,58 @@ static USB* usb = NULL;
 USB::~USB()
 {}
 
+static std::unique_ptr<CandidateDevice> selectDevice()
+{
+	auto candidates = findUsbDevices({ FLUXENGINE_ID, GREASEWEAZLE_ID });
+	if (candidates.size() == 0)
+		Error() << "no devices found (is one plugged in? Do you have the appropriate "
+					"permissions?";
+
+	if (config.usb().has_serial())
+	{
+		auto wantedSerial = config.usb().serial();
+		for (auto& c : candidates)
+		{
+			if (c->serial == wantedSerial)
+				return std::move(c);
+		}
+		Error() << "serial number not found (try without one to list or autodetect devices)";
+	}
+
+	if (candidates.size() == 1)
+		return std::move(candidates[0]);
+
+	std::cerr << "More than one device detected; use --usb.serial=<serial> to select one:\n";
+	for (const auto& c : candidates)
+	{
+		std::cerr << "    ";
+		switch (c->id)
+		{
+			case FLUXENGINE_ID:
+				std::cerr << fmt::format("FluxEngine: {}\n", c->serial);
+				break;
+
+			case GREASEWEAZLE_ID:
+				std::cerr << fmt::format("GreaseWeazle: {} on {}\n", c->serial, c->serialPort);
+				break;
+		}
+	}
+	exit(1);
+}
+
 USB* get_usb_impl()
 {
-	switch (config.usb().device_case())
+	auto candidate = selectDevice();
+	switch (candidate->id)
 	{
-		case UsbProto::kFluxengine:
-		{
-			auto candidates = findUsbDevices(FLUXENGINE_ID);
-			for (auto& c : candidates)
-			{
-				if (c->serial == config.usb().fluxengine())
-					return createFluxengineUsb(c->device);
-			}
-			Error() << "that FluxEngine device could not be found (is it plugged in? Do you have the "
-						"appropriate permissions?";
-		}
+		case FLUXENGINE_ID:
+			return createFluxengineUsb(candidate->device);
 
-		case UsbProto::kGreaseweazle:
-			return createGreaseWeazleUsb(config.usb().greaseweazle());
+		case GREASEWEAZLE_ID:
+			return createGreaseWeazleUsb(candidate->serialPort);
 
 		default:
-		{
-			auto candidates = findUsbDevices(FLUXENGINE_ID);
-			if (candidates.size() == 0)
-				Error() << "no FluxEngine devices found (is one plugged in? Do you have the appropriate "
-							"permissions?";
-			if (candidates.size() != 1)
-			{
-				std::cerr << "More than one FluxEngine detected; use --usb.fluxengine=<serial> to\n"
-								"select one:\n";
-				for (const auto& c : candidates)
-					std::cerr << "    " << c->serial << std::endl;
-				exit(1);
-			}
-			return createFluxengineUsb(candidates[0]->device);
-		}
+			Error() << "internal";
 	}
 }
 

lib/usb/usb.proto

@@ -4,9 +4,7 @@ import "lib/common.proto";
 
 message UsbProto {
 	oneof device {
-		string fluxengine = 1
-			[(help) = "serial number of FluxEngine device to use"];
-		string greaseweazle = 2
-			[(help) = "serial port of GreaseWeazle device to use"];
+		string serial = 1
+			[(help) = "serial number of FluxEngine or GreaseWeazle device to use"];
 	}
 }

lib/usb/usbfinder.cc

@@ -4,6 +4,7 @@
 #include "bytes.h"
 #include "fmt/format.h"
 #include "usbfinder.h"
+#include "greaseweazle.h"
 #include "libusbp.hpp"
 
 static const std::string get_serial_number(const libusbp::device& device)
@@ -20,7 +21,7 @@ static const std::string get_serial_number(const libusbp::device& device)
 	}
 }
 
-std::vector<std::unique_ptr<CandidateDevice>> findUsbDevices(uint32_t candidateId)
+std::vector<std::unique_ptr<CandidateDevice>> findUsbDevices(const std::set<uint32_t>& ids)
 {
 	std::vector<std::unique_ptr<CandidateDevice>> candidates;
 	for (const auto& it : libusbp::list_connected_devices())
@@ -29,10 +30,17 @@ std::vector<std::unique_ptr<CandidateDevice>> findUsbDevices(uint32_t candidateI
 		candidate->device = it;
 
 		uint32_t id = (it.get_vendor_id() << 16) | it.get_product_id();
-		if (id == candidateId)
+		if (ids.contains(id))
 		{
-			candidate->id = candidateId;
+			candidate->id = id;
 			candidate->serial = get_serial_number(it);
+
+			if (id == GREASEWEAZLE_ID)
+			{
+				libusbp::serial_port port(candidate->device);
+				candidate->serialPort = port.get_name();
+			}
+
 			candidates.push_back(std::move(candidate));
 		}
 	}

lib/usb/usbfinder.h

@@ -9,9 +9,10 @@ struct CandidateDevice
 	libusbp::device device;
 	uint32_t id;
 	std::string serial;
+	std::string serialPort;
 };
 
-extern std::vector<std::unique_ptr<CandidateDevice>> findUsbDevices(uint32_t id);
+extern std::vector<std::unique_ptr<CandidateDevice>> findUsbDevices(const std::set<uint32_t>& id);
 
 #endif