介绍 / Introduction
XRUSB 是 LibXR 的 USB 设备协议栈，用 C++20 编写，位于 src/driver/usb。core/ 生成设备、配置、字符串和 BOS 描述符并管理端点池，device/ 是设备核心、 组合设备和各设备类。一个组合设备可以包含多个设备类，初始化时各设备类从端点池申请所需的端点。这个目录 只有平台无关的代码，USB 设备控制器的驱动位于各平台的 driver/<平台>/，例如 driver/st/stm32_usb_dev.cpp、 driver/ch/ch32_usb_otghs.cpp 和 driver/esp/esp_usb_dev.cpp。
XRUSB is the USB device stack of LibXR, written in C++20, in src/driver/usb. core/ builds the device, configuration, string and BOS descriptors and manages the endpoint pool; device/ holds the device core, the composite device and the device classes. A composite device can contain several device classes, and each class takes the endpoints it needs from the endpoint pool at initialization. This directory holds only platform-independent code; the USB device controller drivers are in driver/<platform>/ of each platform, such as driver/st/stm32_usb_dev.cpp, driver/ch/ch32_usb_otghs.cpp and driver/esp/esp_usb_dev.cpp.
平台外设支持列表中的 USB-DEVICE 指 XRUSB 使用的 USB 设备控制器。ESP32-C3 和 ESP32-C6 的 CDC-JTAG 由 driver/esp/esp_cdc_jtag.* 实现，使用芯片自带的 USB Serial/JTAG 控制器，不经过 XRUSB。
USB-DEVICE in the platform peripheral support list means the USB device controller used by XRUSB. CDC-JTAG on ESP32-C3 and ESP32-C6 is implemented by driver/esp/esp_cdc_jtag.* on the chip's own USB Serial/JTAG controller and does not use XRUSB.
设备类 / Device Classes
| 设备类 / Class | 头文件 / Header | 说明 / Notes |
|---|---|---|
| CDC-ACM | device/cdc/cdc_uart.hpp、cdc_to_uart.hpp | CDCUart 作为 LibXR::UART 使用；CDCToUart 把 CDC 与一个 UART 双向桥接 / CDCUart is used as a LibXR::UART; CDCToUart bridges CDC and a UART in both directions |
| HID | device/hid/hid_keyboard.hpp、hid_mouse.hpp、hid_gamepad.hpp | 键盘、鼠标和手柄；其他报告由 HID 派生 / Keyboard, mouse and gamepad; other reports derive from HID |
| UAC | device/uac/uac_mic.hpp | UAC1 麦克风 / UAC1 microphone |
| GS USB | device/gsusb/gs_usb.hpp | CAN 与 CAN FD 适配器，Linux 内核自带的 gs_usb 驱动把它作为 SocketCAN 接口 / CAN and CAN FD adapter that the gs_usb driver of the Linux kernel exposes as a SocketCAN interface |
| DAPLink V1 | device/dap/daplink_v1.hpp | CMSIS-DAP v1（HID），SWD 与 JTAG / CMSIS-DAP v1 (HID), SWD and JTAG |
| DAPLink V2 | device/dap/daplink_v2.hpp | CMSIS-DAP v2（Bulk），SWD 与 JTAG，可用于 Keil 和 OpenOCD / CMSIS-DAP v2 (Bulk), SWD and JTAG, works with Keil and OpenOCD |
| DFU | device/dfu/dfu.hpp、dfu_bootloader.hpp | DFU 运行时接口和单镜像 bootloader / DFU runtime interface and single-image bootloader |
| BOS | device/bos/webusb.hpp、winusb_msos20.hpp | WebUSB 与 WinUSB MS OS 2.0 描述符 / WebUSB and WinUSB MS OS 2.0 descriptors |
device/cdc/cdc_test.hpp 中的 CDCWriteTest 和 CDCReadTest 用于测试 CDC 的传输。
CDCWriteTest and CDCReadTest in device/cdc/cdc_test.hpp test CDC transfers.
设备控制器 / Device Controllers
| 平台 / Platform | 控制器 / Controller | 驱动 / Driver | 测试设备 / Tested on |
|---|---|---|---|
| STM32 | FSDEV（USB_BASE、USB_DRD_FS） | driver/st/stm32_usb_dev.cpp | STM32F103、STM32G431 |
| STM32 | OTG FS（USB_OTG_FS） | driver/st/stm32_usb_dev.cpp | STM32F407 |
| STM32 | OTG HS（USB_OTG_HS） | driver/st/stm32_usb_dev.cpp | STM32F407、STM32H750 |
| ESP32-S3 | OTG FS | driver/esp/esp_usb_dev.cpp | ESP32-S3 |
| CH32 | FSDEV | driver/ch/ch32_usb_devfs.cpp | CH32V203 |
| CH32 | USBFS（OTG FS） | driver/ch/ch32_usb_otgfs.cpp | CH32V307、CH32V203、CH32V208 |
| CH32 | USBHS（OTG HS） | driver/ch/ch32_usb_otghs.cpp | CH32V307 |
STM32 驱动按 CMSIS 设备头文件中定义的外设宏编译对应的控制器。
The STM32 driver compiles the controllers whose peripheral macros the CMSIS device header defines.
文档 / Documentation
Usage is described in XRUSB Stack of the LibXR documentation.
