Descriptors.c

#include "Descriptors.h"

// HID Descriptors.
const USB_Descriptor_HIDReport_Datatype_t PROGMEM JoystickReport[] = {
	HID_RI_USAGE_PAGE(8,1), /* Generic Desktop */
	HID_RI_USAGE(8,5), /* Joystick */
	HID_RI_COLLECTION(8,1), /* Application */
		// Buttons (2 bytes)
		HID_RI_LOGICAL_MINIMUM(8,0),
		HID_RI_LOGICAL_MAXIMUM(8,1),
		HID_RI_PHYSICAL_MINIMUM(8,0),
		HID_RI_PHYSICAL_MAXIMUM(8,1),
		// The Switch will allow us to expand the original HORI descriptors to a full 16 buttons.
		// The Switch will make use of 14 of those buttons.
		HID_RI_REPORT_SIZE(8,1),
		HID_RI_REPORT_COUNT(8,16),
		HID_RI_USAGE_PAGE(8,9),
		HID_RI_USAGE_MINIMUM(8,1),
		HID_RI_USAGE_MAXIMUM(8,16),
		HID_RI_INPUT(8,2),
		// HAT Switch (1 nibble)
		HID_RI_USAGE_PAGE(8,1),
		HID_RI_LOGICAL_MAXIMUM(8,7),
		HID_RI_PHYSICAL_MAXIMUM(16,315),
		HID_RI_REPORT_SIZE(8,4),
		HID_RI_REPORT_COUNT(8,1),
		HID_RI_UNIT(8,20),
		HID_RI_USAGE(8,57),
		HID_RI_INPUT(8,66),
		// There's an additional nibble here that's utilized as part of the Switch Pro Controller.
		// I believe this -might- be separate U/D/L/R bits on the Switch Pro Controller, as they're utilized as four button descriptors on the Switch Pro Controller.
		HID_RI_UNIT(8,0),
		HID_RI_REPORT_COUNT(8,1),
		HID_RI_INPUT(8,1),
		// Joystick (4 bytes)
		HID_RI_LOGICAL_MAXIMUM(16,255),
		HID_RI_PHYSICAL_MAXIMUM(16,255),
		HID_RI_USAGE(8,48),
		HID_RI_USAGE(8,49),
		HID_RI_USAGE(8,50),
		HID_RI_USAGE(8,53),
		HID_RI_REPORT_SIZE(8,8),
		HID_RI_REPORT_COUNT(8,4),
		HID_RI_INPUT(8,2),
		// ??? Vendor Specific (1 byte)
		// This byte requires additional investigation.
		HID_RI_USAGE_PAGE(16,65280),
		HID_RI_USAGE(8,32),
		HID_RI_REPORT_COUNT(8,1),
		HID_RI_INPUT(8,2),
		// Output (8 bytes)
		// Original observation of this suggests it to be a mirror of the inputs that we sent.
		// The Switch requires us to have these descriptors available.
		HID_RI_USAGE(16,9761),
		HID_RI_REPORT_COUNT(8,8),
		HID_RI_OUTPUT(8,2),
	HID_RI_END_COLLECTION(0),
};

// Device Descriptor Structure
const USB_Descriptor_Device_t PROGMEM DeviceDescriptor = {
	.Header                 = {.Size = sizeof(USB_Descriptor_Device_t), .Type = DTYPE_Device},

	.USBSpecification       = VERSION_BCD(2,0,0),
	.Class                  = USB_CSCP_NoDeviceClass,
	.SubClass               = USB_CSCP_NoDeviceSubclass,
	.Protocol               = USB_CSCP_NoDeviceProtocol,

	.Endpoint0Size          = FIXED_CONTROL_ENDPOINT_SIZE,

	.VendorID               = 0x0F0D,
	.ProductID              = 0x0092,
	.ReleaseNumber          = VERSION_BCD(1,0,0),

	.ManufacturerStrIndex   = STRING_ID_Manufacturer,
	.ProductStrIndex        = STRING_ID_Product,
	.SerialNumStrIndex      = NO_DESCRIPTOR,

	.NumberOfConfigurations = FIXED_NUM_CONFIGURATIONS
};

// Configuration Descriptor Structure
const USB_Descriptor_Configuration_t PROGMEM ConfigurationDescriptor = {
	.Config =
		{
			.Header                 = {.Size = sizeof(USB_Descriptor_Configuration_Header_t), .Type = DTYPE_Configuration},

			.TotalConfigurationSize = sizeof(USB_Descriptor_Configuration_t),
			.TotalInterfaces        = 1,

			.ConfigurationNumber    = 1,
			.ConfigurationStrIndex  = NO_DESCRIPTOR,

			.ConfigAttributes       = USB_CONFIG_ATTR_RESERVED|USB_CONFIG_ATTR_REMOTEWAKEUP,

			.MaxPowerConsumption    = USB_CONFIG_POWER_MA(500)
		},

	.HID_Interface =
		{
			.Header                 = {.Size = sizeof(USB_Descriptor_Interface_t), .Type = DTYPE_Interface},

			.InterfaceNumber        = INTERFACE_ID_Joystick,
			.AlternateSetting       = 0x00,

			.TotalEndpoints         = 2,

			.Class                  = HID_CSCP_HIDClass,
			.SubClass               = HID_CSCP_NonBootSubclass,
			.Protocol               = HID_CSCP_NonBootProtocol,

			.InterfaceStrIndex      = NO_DESCRIPTOR
		},

	.HID_JoystickHID =
		{
			.Header                 = {.Size = sizeof(USB_HID_Descriptor_HID_t), .Type = HID_DTYPE_HID},

			.HIDSpec                = VERSION_BCD(1,1,1),
			.CountryCode            = 0x00,
			.TotalReportDescriptors = 1,
			.HIDReportType          = HID_DTYPE_Report,
			.HIDReportLength        = sizeof(JoystickReport)
		},

	.HID_ReportINEndpoint =
		{
			.Header                 = {.Size = sizeof(USB_Descriptor_Endpoint_t), .Type = DTYPE_Endpoint},

			.EndpointAddress        = JOYSTICK_IN_EPADDR,
			.Attributes             = (EP_TYPE_INTERRUPT | ENDPOINT_ATTR_NO_SYNC | ENDPOINT_USAGE_DATA),
			.EndpointSize           = JOYSTICK_EPSIZE,
			.PollingIntervalMS      = 0x01
		},

	.HID_ReportOUTEndpoint =
		{
			.Header                 = {.Size = sizeof(USB_Descriptor_Endpoint_t), .Type = DTYPE_Endpoint},

			.EndpointAddress        = JOYSTICK_OUT_EPADDR,
			.Attributes             = (EP_TYPE_INTERRUPT | ENDPOINT_ATTR_NO_SYNC | ENDPOINT_USAGE_DATA),
			.EndpointSize           = JOYSTICK_EPSIZE,
			.PollingIntervalMS      = 0x01
		},
};

// Language Descriptor Structure
const USB_Descriptor_String_t PROGMEM LanguageString = USB_STRING_DESCRIPTOR_ARRAY(LANGUAGE_ID_ENG);

// Manufacturer and Product Descriptor Strings
const USB_Descriptor_String_t PROGMEM ManufacturerString = USB_STRING_DESCRIPTOR(L"ELMAGNIFICO");
const USB_Descriptor_String_t PROGMEM ProductString      = USB_STRING_DESCRIPTOR(L"MCU CONTROLLER");

// USB Device Callback - Get Descriptor
uint16_t CALLBACK_USB_GetDescriptor(
	const uint16_t wValue,
	const uint16_t wIndex,
	const void** const DescriptorAddress
) {
	const uint8_t  DescriptorType   = (wValue >> 8);
	const uint8_t  DescriptorNumber = (wValue & 0xFF);

	const void* Address = NULL;
	uint16_t    Size    = NO_DESCRIPTOR;

	switch (DescriptorType)
	{
		case DTYPE_Device:
			Address = &DeviceDescriptor;
			Size    = sizeof(USB_Descriptor_Device_t);
			break;
		case DTYPE_Configuration:
			Address = &ConfigurationDescriptor;
			Size    = sizeof(USB_Descriptor_Configuration_t);
			break;
		case DTYPE_String:
			switch (DescriptorNumber)
			{
				case STRING_ID_Language:
					Address = &LanguageString;
					Size    = pgm_read_byte(&LanguageString.Header.Size);
					break;
				case STRING_ID_Manufacturer:
					Address = &ManufacturerString;
					Size    = pgm_read_byte(&ManufacturerString.Header.Size);
					break;
				case STRING_ID_Product:
					Address = &ProductString;
					Size    = pgm_read_byte(&ProductString.Header.Size);
					break;
			}

			break;
		case DTYPE_HID:
			Address = &ConfigurationDescriptor.HID_JoystickHID;
			Size    = sizeof(USB_HID_Descriptor_HID_t);
			break;
		case DTYPE_Report:
			Address = &JoystickReport;
			Size    = sizeof(JoystickReport);
			break;
	}

	*DescriptorAddress = Address;
	return Size;
}