Frequent disconnectsAdded optional EMPTY_PACKET_DISCONNECT build-flag to disable empty-packet-disconnects

Makefile

@@ -1,10 +1,13 @@
 BUILD := DEBUG
 VERSION := $(shell git describe --tags)
 
+EMPTY_PACKET_DISCONNECT := 1
+CONFIG := $(CONFIG) -DEMPTY_PACKET_DISCONNECT=$(EMPTY_PACKET_DISCONNECT)
+
 FLAGS := -Wall -Wpedantic -std=c++11 -MMD -MP
 DEBUG_FLAGS := -Og -g -DDEBUG
 RELEASE_FLAGS := -O3
-DEFINES := -DVERSION=\"$(VERSION)\"
+DEFINES := -DVERSION=\"$(VERSION)\" $(CONFIG)
 
 CXXFLAGS += $(FLAGS) $($(BUILD)_FLAGS) $(DEFINES)
 LDLIBS += -lpthread -lusb-1.0

README.md

@@ -51,7 +51,7 @@ The following Xbox One controllers are currently compatible with the driver:
 | 1698         | 2015 | Elite controller          | **Working**  |
 | 1708         | 2016 | Bluetooth connectivity    | **Working**  |
 | 1797         | 2019 | Elite controller series 2 | **Working**  |
-| 1914         | 2020 | Share button and USB-C    | **Untested** |
+| 1914         | 2020 | Share button and USB-C    | **Working**  |
 
 ## Releases
 
@@ -163,6 +163,15 @@ The controller only remembers the *last* device it was connected to. It will not
 Some USB controllers are known to cause issues with xow. Plugging your dongle into a USB port that uses an `ASMedia` controller will lead to problems. Most `Intel` USB controllers work well with xow.
 Power management issues can arise when using a USB 3 controller. These can lead to timeouts of the USB communication. The use of a USB hub can mitigate these problems.
 
+### Controller periodically disconnects (when idle)
+Some controllers might periodically disconnect due to xow receiving an empty packet (which should not happen for most controllers).
+This usually happens when the controller is not receiving any input, but can still happen when being used.
+As a result, you can disable the automatic disconnect when building by using the `EMPTY_PACKET_DISCONNECT` flag as shown below:
+
+```
+make BUILD=RELEASE EMPTY_PACKET_DISCONNECT=0
+```
+
 ### Other problems
 
 In case of any other problems, please open an issue with all the relevant details (dongle version, controller version, logs, captures, etc.).

dongle/dongle.cpp

@@ -18,6 +18,7 @@
 
 #include "dongle.h"
 #include "../utils/log.h"
+#include "../utils/macros.h"
 
 Dongle::Dongle(
     std::unique_ptr<UsbDevice> usbDevice
@@ -269,7 +270,9 @@ void Dongle::handleBulkData(const Bytes &data)
 
             case EVT_CLIENT_LOST:
                 // Packet is guaranteed not to be empty
+                #if IS_PROP_ENABLED(EMPTY_PACKET_DISCONNECT)
                 handleControllerDisconnect(packet[0]);
+                #endif
                 break;
         }
     }

utils/macros.h

@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2019 Medusalix
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+// Define helper macros for property expansion
+#define DO_EXPAND(VAL)        VAL ## 1
+#define GET_VALUE(VAL)        DO_EXPAND(VAL)
+#define IS_PROP_ENABLED(VAL)  GET_VALUE(VAL) != 1
+