hidapi: Add support for NSO GameCube controller via libusb

flibitijibibo · flibitijibibo · commit 27346e07621f · 2025-07-05T19:37:33.000-04:00
Thanks to Nohzockt for the initial libusb init and hidapi polling work!
diff --git a/src/hidapi/SDL_hidapi.c b/src/hidapi/SDL_hidapi.c
@@ -743,6 +743,14 @@ static struct
         int *actual_length,
         unsigned int timeout
     );
+    int (LIBUSB_CALL *bulk_transfer)(
+        libusb_device_handle *dev_handle,
+        unsigned char endpoint,
+        unsigned char *data,
+        int length,
+        int *transferred,
+        unsigned int timeout
+    );
     int (LIBUSB_CALL *handle_events)(libusb_context *ctx);
     int (LIBUSB_CALL *handle_events_completed)(libusb_context *ctx, int *completed);
     const char * (LIBUSB_CALL *error_name)(int errcode);
@@ -776,6 +784,7 @@ static struct
 #define libusb_free_transfer                libusb_ctx.free_transfer
 #define libusb_control_transfer             libusb_ctx.control_transfer
 #define libusb_interrupt_transfer           libusb_ctx.interrupt_transfer
+#define libusb_bulk_transfer                libusb_ctx.bulk_transfer
 #define libusb_handle_events                libusb_ctx.handle_events
 #define libusb_handle_events_completed      libusb_ctx.handle_events_completed
 #define libusb_error_name                   libusb_ctx.error_name
@@ -843,6 +852,7 @@ typedef struct LIBUSB_hid_device_ LIBUSB_hid_device;
 #undef libusb_free_transfer
 #undef libusb_control_transfer
 #undef libusb_interrupt_transfer
+#undef libusb_bulk_transfer
 #undef libusb_handle_events
 #undef libusb_handle_events_completed
 #undef libusb_error_name
@@ -889,7 +899,8 @@ static const struct {
     Uint16 vendor;
     Uint16 product;
 } SDL_libusb_whitelist[] = {
-    { 0x057e, 0x0337 } // Nintendo WUP-028, Wii U/Switch GameCube Adapter
+    { 0x057e, 0x0337 }, // Nintendo WUP-028, Wii U/Switch GameCube Adapter
+    { 0x057e, 0x2073 }, // Nintendo Switch 2 NSO GameCube Controller
 };
 
 static bool IsInWhitelist(Uint16 vendor, Uint16 product)
@@ -1212,6 +1223,7 @@ int SDL_hid_init(void)
             LOAD_LIBUSB_SYMBOL(void (LIBUSB_CALL *)(struct libusb_transfer *), free_transfer)
             LOAD_LIBUSB_SYMBOL(int (LIBUSB_CALL *)(libusb_device_handle *, uint8_t, uint8_t, uint16_t, uint16_t, unsigned char *, uint16_t, unsigned int), control_transfer)
             LOAD_LIBUSB_SYMBOL(int (LIBUSB_CALL *)(libusb_device_handle *, unsigned char, unsigned char *, int, int *, unsigned int), interrupt_transfer)
+            LOAD_LIBUSB_SYMBOL(int (LIBUSB_CALL *)(libusb_device_handle *, unsigned char, unsigned char *, int, int *, unsigned int), bulk_transfer)
             LOAD_LIBUSB_SYMBOL(int (LIBUSB_CALL *)(libusb_context *), handle_events)
             LOAD_LIBUSB_SYMBOL(int (LIBUSB_CALL *)(libusb_context *, int *), handle_events_completed)
             LOAD_LIBUSB_SYMBOL(const char * (LIBUSB_CALL *)(int), error_name)
diff --git a/src/hidapi/libusb/hid.c b/src/hidapi/libusb/hid.c
@@ -1307,6 +1307,66 @@ static void init_xboxone(libusb_device_handle *device_handle, unsigned short idV
 	}
 }
 
+static bool switch2_find_bulk_out_endpoint(libusb_device_handle* handle, uint8_t* endpoint_out)
+{
+	struct libusb_config_descriptor* config;
+	if (libusb_get_config_descriptor(libusb_get_device(handle), 0, &config) != 0) {
+		return false;
+	}
+
+	for (int i = 0; i < config->bNumInterfaces; i++) {
+		const struct libusb_interface* iface = &config->interface[i];
+		for (int j = 0; j < iface->num_altsetting; j++) {
+			const struct libusb_interface_descriptor* altsetting = &iface->altsetting[j];
+			if (altsetting->bInterfaceNumber == 1) {
+				for (int k = 0; k < altsetting->bNumEndpoints; k++) {
+					const struct libusb_endpoint_descriptor* ep = &altsetting->endpoint[k];
+					if ((ep->bmAttributes & LIBUSB_TRANSFER_TYPE_MASK) == LIBUSB_TRANSFER_TYPE_BULK && (ep->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK) == LIBUSB_ENDPOINT_OUT) {
+						*endpoint_out = ep->bEndpointAddress;
+						libusb_free_config_descriptor(config);
+						return true;
+					}
+				}
+			}
+		}
+	}
+
+	libusb_free_config_descriptor(config);
+	return false;
+}
+
+static void init_nsogcn(libusb_device_handle *device_handle)
+{
+	const unsigned char DEFAULT_REPORT_DATA[] = {
+		0x03, 0x91, 0x00, 0x0d, 0x00, 0x08,
+		0x00, 0x00, 0x01, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
+	};
+	const unsigned char SET_LED_DATA[] = {
+		0x09, 0x91, 0x00, 0x07, 0x00, 0x08,
+		0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+	};
+
+	uint8_t endpoint_out = 0;
+	if (!switch2_find_bulk_out_endpoint(device_handle, &endpoint_out)) {
+		return;
+	}
+
+	int transferred;
+	libusb_bulk_transfer(device_handle,
+				endpoint_out,
+				(unsigned char*)DEFAULT_REPORT_DATA,
+				sizeof(DEFAULT_REPORT_DATA),
+				&transferred,
+				1000);
+
+	libusb_bulk_transfer(device_handle,
+				endpoint_out,
+				(unsigned char*)SET_LED_DATA,
+				sizeof(SET_LED_DATA),
+				&transferred,
+				1000);
+}
+
 static void calculate_device_quirks(hid_device *dev, unsigned short idVendor, unsigned short idProduct)
 {
 	static const int VENDOR_SONY = 0x054c;
@@ -1368,6 +1428,11 @@ static int hidapi_initialize_device(hid_device *dev, const struct libusb_interfa
 		init_xboxone(dev->device_handle, desc.idVendor, desc.idProduct, conf_desc);
 	}
 
+	/* Initialize NSO GameCube controllers */
+	if ((desc.idVendor == 0x057e) && (desc.idProduct == 0x2073)) {
+		init_nsogcn(dev->device_handle);
+	}
+
 	/* Store off the string descriptor indexes */
 	dev->manufacturer_index = desc.iManufacturer;
 	dev->product_index      = desc.iProduct;
diff --git a/src/joystick/SDL_gamepad.c b/src/joystick/SDL_gamepad.c
@@ -715,6 +715,10 @@ static GamepadMapping_t *SDL_CreateMappingForHIDAPIGamepad(SDL_GUID guid)
           product == USB_PRODUCT_EVORETRO_GAMECUBE_ADAPTER3))) {
         // GameCube driver has 12 buttons and 6 axes
         SDL_strlcat(mapping_string, "a:b0,b:b2,dpdown:b6,dpleft:b4,dpright:b5,dpup:b7,lefttrigger:a4,leftx:a0,lefty:a1~,rightshoulder:b9,righttrigger:a5,rightx:a2,righty:a3~,start:b8,x:b1,y:b3,hint:!SDL_GAMECONTROLLER_USE_GAMECUBE_LABELS:=1,", sizeof(mapping_string));
+    } else if (vendor == USB_VENDOR_NINTENDO &&
+               (product == USB_PRODUCT_NINTENDO_SWITCH2_GAMECUBE_CONTROLLER)) {
+        // Switch 2 GameCube has additional buttons for ZL and C
+        SDL_strlcat(mapping_string, "a:b1,b:b3,dpdown:b8,dpleft:b10,dpright:b9,dpup:b11,guide:b16,leftshoulder:b13,lefttrigger:a4,leftx:a0,lefty:a1~,misc1:17,misc2:20,rightshoulder:b5,righttrigger:a5,rightx:a2,righty:a3~,start:b6,x:b0,y:b2,hint:!SDL_GAMECONTROLLER_USE_GAMECUBE_LABELS:=1,", sizeof(mapping_string));
     } else if (vendor == USB_VENDOR_NINTENDO &&
                (guid.data[15] == k_eSwitchDeviceInfoControllerType_HVCLeft ||
                 guid.data[15] == k_eSwitchDeviceInfoControllerType_HVCRight ||
diff --git a/src/joystick/SDL_joystick.c b/src/joystick/SDL_joystick.c
@@ -487,6 +487,7 @@ static Uint32 initial_gamecube_devices[] = {
     MAKE_VIDPID(0x0e6f, 0x0185), // PDP Wired Fight Pad Pro for Nintendo Switch
     MAKE_VIDPID(0x1a34, 0xf705), // GameCube {HuiJia USB box}
     MAKE_VIDPID(0x20d6, 0xa711), // PowerA Wired Controller Nintendo GameCube Style
+    MAKE_VIDPID(0x057e, 0x2073), // Nintendo Switch 2 NSO GameCube Controller
 };
 static SDL_vidpid_list gamecube_devices = {
     SDL_HINT_JOYSTICK_GAMECUBE_DEVICES, 0, 0, NULL,
diff --git a/src/joystick/hidapi/SDL_hidapi_switch2.c b/src/joystick/hidapi/SDL_hidapi_switch2.c
@@ -61,7 +61,9 @@ static bool HIDAPI_DriverSwitch2_IsSupportedDevice(SDL_HIDAPI_Device *device, co
 
 static bool HIDAPI_DriverSwitch2_InitDevice(SDL_HIDAPI_Device *device)
 {
-    return false;
+    HIDAPI_SetDeviceName(device, "Nintendo Switch 2 GameCube Controller");
+    HIDAPI_SetDeviceProduct(device, USB_VENDOR_NINTENDO, USB_PRODUCT_NINTENDO_SWITCH2_GAMECUBE_CONTROLLER);
+    return HIDAPI_JoystickConnected(device, NULL);
 }
 
 static int HIDAPI_DriverSwitch2_GetDevicePlayerIndex(SDL_HIDAPI_Device *device, SDL_JoystickID instance_id)
@@ -75,12 +77,79 @@ static void HIDAPI_DriverSwitch2_SetDevicePlayerIndex(SDL_HIDAPI_Device *device,
 
 static bool HIDAPI_DriverSwitch2_UpdateDevice(SDL_HIDAPI_Device *device)
 {
-    return false;
+    const struct {
+        int byte;
+        unsigned char mask;
+    } buttons[] = {
+        {3, 0x01}, // B
+        {3, 0x02}, // A
+        {3, 0x04}, // Y
+        {3, 0x08}, // X
+        {3, 0x10}, // R (GameCube R Click)
+        {3, 0x20}, // ZR (GameCube Z)
+        {3, 0x40}, // PLUS (GameCube Start)
+        {3, 0x80}, // RS (not on GameCube)
+        {4, 0x01}, // DPAD_DOWN
+        {4, 0x02}, // DPAD_RIGHT
+        {4, 0x04}, // DPAD_LEFT
+        {4, 0x08}, // DPAD_UP
+        {4, 0x10}, // L (GameCube L Click)
+        {4, 0x20}, // ZL
+        {4, 0x40}, // MINUS (not on GameCube)
+        {4, 0x80}, // LS (not on GameCube)
+        {5, 0x01}, // Home
+        {5, 0x02}, // Capture
+        {5, 0x04}, // GR (not on GameCube)
+        {5, 0x08}, // GL (not on GameCube)
+        {5, 0x10}, // C
+    };
+
+    SDL_Joystick *joystick = NULL;
+    if (device->num_joysticks > 0) {
+        joystick = SDL_GetJoystickFromID(device->joysticks[0]);
+    }
+    if (joystick == NULL) {
+        return true;
+    }
+
+    // Read input packet
+
+    Uint8 packet[USB_PACKET_LENGTH];
+    int size;
+    while ((size = SDL_hid_read_timeout(device->dev, packet, sizeof(packet), 0)) > 0) {
+        if (size > 14) {
+            Uint64 timestamp = SDL_GetTicksNS();
+            for (size_t i = 0; i < SDL_arraysize(buttons); ++i) {
+                SDL_SendJoystickButton(
+                    timestamp,
+                    joystick,
+                    (Uint8) i,
+                    (packet[buttons[i].byte] & buttons[i].mask) != 0);
+            }
+            SDL_SendJoystickAxis(
+                timestamp,
+                joystick,
+                SDL_GAMEPAD_AXIS_LEFT_TRIGGER,
+                (Sint16) HIDAPI_RemapVal(packet[13], 0, 255, SDL_MIN_SINT16, SDL_MAX_SINT16)
+            );
+            SDL_SendJoystickAxis(
+                timestamp,
+                joystick,
+                SDL_GAMEPAD_AXIS_RIGHT_TRIGGER,
+                (Sint16) HIDAPI_RemapVal(packet[14], 0, 255, SDL_MIN_SINT16, SDL_MAX_SINT16)
+            );
+        }
+    }
+    return true;
 }
 
 static bool HIDAPI_DriverSwitch2_OpenJoystick(SDL_HIDAPI_Device *device, SDL_Joystick *joystick)
 {
-    return false;
+    // Initialize the joystick capabilities
+    joystick->nbuttons = 21;
+    joystick->naxes = SDL_GAMEPAD_AXIS_COUNT;
+
+    return true;
 }
 
 static bool HIDAPI_DriverSwitch2_RumbleJoystick(SDL_HIDAPI_Device *device, SDL_Joystick *joystick, Uint16 low_frequency_rumble, Uint16 high_frequency_rumble)
