firmware: add WCID descriptors

firmware/src/boards/daisho/usb_descriptors.c

@@ -131,9 +131,17 @@ uint16_t const* tud_descriptor_string_cb(uint8_t index)
 	{
 		// Convert ASCII string into UTF-16
 
-		if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL;
-
-		const char* str = string_desc_arr[index];
+		const char* str;
+		if (index == 0xee) {
+			// Microsoft OS 1.0 String Descriptor
+			str = "MSFT100\xee\x01";
+		} else {
+			if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) {
+				return NULL;
+			}
+
+			str = string_desc_arr[index];
+		}
 
 		// Cap at max char
 		chr_count = strlen(str);

firmware/src/mcu/samd11/usb_descriptors.c

@@ -38,11 +38,12 @@ tusb_desc_device_t const desc_device =
 	.bDescriptorType    = TUSB_DESC_DEVICE,
 	.bcdUSB             = 0x0200,
 
-	// Use Interface Association Descriptor (IAD) for CDC
-	// As required by USB Specs IAD's subclass must be common class (2) and protocol must be IAD (1)
-	.bDeviceClass       = TUSB_CLASS_MISC,
-	.bDeviceSubClass    = MISC_SUBCLASS_COMMON,
-	.bDeviceProtocol    = MISC_PROTOCOL_IAD,
+	// We use bDeviceClass = 0 to indicate that we're a composite device.
+	// Another option is to use the Interface Association Descriptor (IAD) method, 
+	// but this requires extra descriptors.
+	.bDeviceClass       = 0,
+	.bDeviceSubClass    = 0,
+	.bDeviceProtocol    = 0,
 
 	.bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,
 
@@ -185,20 +186,26 @@ uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
 	// Otherwise, take the ASCII string provided and encode it as UTF-16.
 	else {
 
-	if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) {
-		return NULL;
-	}
+		const char* str;
+		if (index == 0xee) {
+			// Microsoft OS 1.0 String Descriptor
+			str = "MSFT100\xee\x01";
+		} else {
+			if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) {
+				return NULL;
+			}
 
-	const char* str = string_desc_arr[index];
+			str = string_desc_arr[index];
+		}
 
-	// Cap at max char
-	chr_count = strlen(str);
-	if ( chr_count > 31 ) chr_count = 31;
+		// Cap at max char
+		chr_count = strlen(str);
+		if ( chr_count > 31 ) chr_count = 31;
 
-	for(uint8_t i=0; i<chr_count; i++)
-	{
-		_desc_str[1+i] = str[i];
-	}
+		for(uint8_t i=0; i<chr_count; i++)
+		{
+			_desc_str[1+i] = str[i];
+		}
 	}
 
 	// first byte is length (including header), second byte is string type

firmware/src/vendor.c

@@ -62,9 +62,44 @@ enum {
 	//
 	// Self-test requests.
 	//
-	VENDOR_REQUEST_GET_RAIL_VOLTAGE      = 0xe0
+	VENDOR_REQUEST_GET_RAIL_VOLTAGE      = 0xe0,
+
+	//
+	// Microsoft WCID descriptor request
+	//
+	VENDOR_REQUEST_GET_MS_DESCRIPTOR     = 0xee,
 };
 
+// Microsoft OS 1.0 descriptor
+uint8_t desc_ms_os_10[] = {
+	// Header: length, bcdVersion, wIndex, bCount, reserved[7]
+	U32_TO_U8S_LE(0x0028),
+	U16_TO_U8S_LE(0x0100),
+	U16_TO_U8S_LE(0x0004),
+	0x01,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+
+	// Compatible ID: bFirstInterfaceNumber, reserved[1], compatibleID[8], subCompatibleID[8], reserved[6]
+	0x02,
+	0x01, 
+	'W', 'I', 'N', 'U', 'S', 'B', 0x00, 0x00, 
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
+};
+
+
+/**
+ * Request Microsoft Windows Compatible ID descriptor.
+*/
+bool handle_get_ms_descriptor(uint8_t rhport, tusb_control_request_t const* request)
+{
+	if (request->wIndex == 0x0004) {
+		return tud_control_xfer(rhport, request, desc_ms_os_10, sizeof(desc_ms_os_10));
+	} else {
+		return false;
+	}
+}
+
 
 /**
  * Simple request that's used to identify the running firmware; mostly a sanity check.
@@ -181,6 +216,9 @@ static bool handle_vendor_request_setup(uint8_t rhport, tusb_control_request_t c
 			return handle_get_rail_voltage(rhport, request);
 		*/
 
+		case VENDOR_REQUEST_GET_MS_DESCRIPTOR:
+			return handle_get_ms_descriptor(rhport, request);
+
 		default:
 			return false;
 	}