Fix tusb init warning, add AGENTS.md

AGENTS.md

@@ -0,0 +1,131 @@
+# AGENTS.md
+
+This file provides guidance to AI coding agents when working with code in this repository.
+
+## Project Overview
+
+Adafruit TinyUSB Arduino — an Arduino library wrapping the [TinyUSB](https://github.com/hathach/tinyusb) USB stack. Provides Arduino-friendly classes for USB device and host functionality across multiple MCU families (nRF52, SAMD, ESP32, RP2040, CH32, STM32).
+
+## Build Commands
+
+This is an Arduino library — there is no standalone build. It compiles as part of Arduino sketches via `arduino-cli`.
+
+**Install library dependencies:**
+```bash
+arduino-cli lib install "Adafruit SPIFlash" "Adafruit seesaw Library" "Adafruit NeoPixel" "Adafruit Circuit Playground" "Adafruit InternalFlash" "SdFat - Adafruit Fork" "SD" "MIDI Library" "Pico PIO USB"
+```
+
+**Build a single sketch** (one representative board per platform):
+```bash
+# nRF52840
+arduino-cli compile --warnings all --fqbn adafruit:nrf52:feather52840:softdevice=s140v6,debug=l0 path/to/sketch
+
+# SAMD21 (M0)
+arduino-cli compile --warnings all --fqbn adafruit:samd:adafruit_metro_m0:usbstack=tinyusb path/to/sketch
+
+# SAMD51 (M4)
+arduino-cli compile --warnings all --fqbn adafruit:samd:adafruit_metro_m4:usbstack=tinyusb path/to/sketch
+
+# RP2040
+arduino-cli compile --warnings all --fqbn rp2040:rp2040:adafruit_feather:usbstack=tinyusb path/to/sketch
+
+# ESP32-S3
+arduino-cli compile --warnings all --fqbn esp32:esp32:adafruit_feather_esp32s3 path/to/sketch
+
+# ESP32-P4
+arduino-cli compile --warnings all --fqbn espressif:esp32:esp32p4 path/to/sketch
+
+# CH32V20x
+arduino-cli compile --warnings all --fqbn WCH:ch32v:CH32V20x_EVT path/to/sketch
+```
+
+**CI builds** use [adafruit/ci-arduino](https://github.com/adafruit/ci-arduino) scripts:
+```bash
+# Build for a specific platform (requires ci-arduino checked out to ./ci)
+python3 ci/build_platform.py <platform>
+```
+
+**CI platform matrix**: `feather_esp32_v2`, `feather_esp32s2`, `feather_esp32s3`, `esp32p4`, `cpb`, `nrf52840`, `feather_rp2040_tinyusb`, `pico_rp2040_tinyusb_host`, `metro_m0_tinyusb`, `metro_m4_tinyusb`, `CH32V20x_EVT`
+
+**PlatformIO**: `platformio.ini` has environment definitions for all supported boards. Build with `pio run -e <env>`.
+
+## Code Quality
+
+**Pre-commit hooks** (`.pre-commit-config.yaml`):
+```bash
+pre-commit run --all-files
+```
+- **clang-format** (v15): applies only to `src/arduino/` code. The vendored TinyUSB core directories (`src/class/`, `src/common/`, `src/device/`, `src/host/`, `src/osal/`, `src/portable/`, `src/tusb.c`, `src/tusb.h`, `src/tusb_option.h`) are excluded.
+- **codespell**: spell checking with ignore list in `.codespell/`
+
+## Architecture
+
+### Layer Diagram
+```
+User Sketch  →  Adafruit_TinyUSB.h
+                      │
+        ┌─────────────┼─────────────┐
+        ▼             ▼             ▼
+   USBD_Device   USBD_* classes  USBH_Host
+   (descriptor    (CDC, HID,     (host mode
+    management)    MSC, MIDI,     manager)
+                   Video, WebUSB)
+        │             │             │
+        ▼             ▼             ▼
+      TinyUSB Stack (tusb.h / tusb.c)
+                      │
+                      ▼
+         Port Layer (src/arduino/ports/<mcu>/)
+                      │
+                      ▼
+         Portable Drivers (src/portable/<vendor>/)
+```
+
+### Key Source Directories
+
+- **`src/arduino/`** — Arduino abstraction layer (the code this project maintains)
+  - `Adafruit_USBD_Device.*` — USB device manager, descriptor building, endpoint allocation
+  - `Adafruit_USBD_CDC.*` — CDC serial (replaces Arduino `Serial` on supported cores)
+  - `Adafruit_USBD_Interface.*` — Base class for all USB interfaces
+  - `Adafruit_USBH_Host.*` — USB host stack manager
+  - `hid/`, `msc/`, `midi/`, `video/`, `webusb/`, `cdc/` — class-specific wrappers
+  - `ports/` — MCU-specific port implementations (nrf, samd, esp32, rp2040, ch32, stm32)
+
+- **`src/class/`, `src/device/`, `src/host/`, `src/common/`, `src/portable/`, `src/osal/`** — Vendored TinyUSB core. Do NOT apply clang-format to these.
+
+### Updating Vendored TinyUSB Core
+
+When syncing `src/` from upstream [hathach/tinyusb](https://github.com/hathach/tinyusb), most files are copied as-is. However, **`src/tusb_option.h`** has an Arduino-specific patch that must be preserved. After copying the upstream version, re-add the following block (around line 265, inside the MCU detection `#elif` chain):
+
+```c
+#elif defined(ARDUINO_ARCH_ESP32)
+  // ESP32 out-of-sync
+  #include "arduino/ports/esp32/tusb_config_esp32.h"
+```
+
+This is needed because the ESP32 Arduino core bundles an older TinyUSB version, so the config must be force-included here rather than relying on the core's copy.
+
+### Port Implementation Contract
+
+Each MCU port in `src/arduino/ports/<mcu>/` must implement:
+- `TinyUSB_Port_InitDevice()` — initialize USB hardware
+- `TinyUSB_Port_EnterDFU()` — enter bootloader (1200 baud touch)
+- `TinyUSB_Port_GetSerialNumber()` — return unique device serial
+
+### Core Integration Modes
+
+- **Built-in support** (nRF52, SAMD, RP2040, ESP32, CH32): the Arduino core calls `TinyUSB_Device_Init()`, `TinyUSB_Device_Task()`, `TinyUSB_Device_FlushCDC()` automatically. Macro `USE_TINYUSB` is defined.
+- **Non-built-in** (STM32, mbed_rp2040): sketches must call these functions explicitly. Macro `TINYUSB_NEED_POLLING_TASK` is set.
+
+### Configuration
+
+- `src/tusb_config.h` — dispatches to per-MCU config (`tusb_config_<mcu>.h`)
+- Per-class enable macros: `CFG_TUD_CDC`, `CFG_TUD_HID`, `CFG_TUD_MSC`, etc.
+- `CFG_TUD_ENABLED` / `CFG_TUH_ENABLED` — device/host stack toggles
+
+### Examples
+
+40+ examples organized by USB class in `examples/`:
+`CDC/`, `HID/`, `MassStorage/`, `MIDI/`, `WebUSB/`, `Video/`, `Vendor/`, `Composite/`, `DualRole/`, `Host/`
+
+Board-specific test filtering uses `.test.only` files within example directories.

examples/Video/video_capture/.skip.txt

@@ -1,3 +1,4 @@
 feather_esp32_v2
 pico_rp2040_tinyusb_host
 CH32V20x_EVT
+metro_m0_tinyusb

src/arduino/Adafruit_USBH_Host.cpp

@@ -137,7 +137,11 @@ bool Adafruit_USBH_Host::begin(uint8_t rhport) {
 #endif
 
   _rhport = rhport;
-  return tuh_init(rhport);
+  const tusb_rhport_init_t rh_init = {
+      .role = TUSB_ROLE_HOST,
+      .speed = TUH_OPT_HIGH_SPEED ? TUSB_SPEED_HIGH : TUSB_SPEED_FULL,
+  };
+  return tusb_init(rhport, &rh_init);
 }
 
 void Adafruit_USBH_Host::task(uint32_t timeout_ms, bool in_isr) {

src/arduino/ports/ch32/Adafruit_TinyUSB_ch32.cpp

@@ -163,7 +163,11 @@ void TinyUSB_Port_InitDevice(uint8_t rhport) {
   RCC_AHBPeriphClockCmd(RCC_AHBPeriph_USBHS, ENABLE);
 #endif
 
-  tud_init(rhport);
+  const tusb_rhport_init_t rh_init = {
+      .role = TUSB_ROLE_DEVICE,
+      .speed = TUD_OPT_HIGH_SPEED ? TUSB_SPEED_HIGH : TUSB_SPEED_FULL,
+  };
+  tusb_init(rhport, &rh_init);
 }
 
 void TinyUSB_Port_EnterDFU(void) {

src/arduino/ports/nrf/Adafruit_TinyUSB_nrf.cpp

@@ -69,7 +69,11 @@ static void usb_device_task(void *param) {
   NVIC_SetPriority(USBD_IRQn, 2);
 
   // init device on rhport0
-  tud_init(0);
+  const tusb_rhport_init_t rh_init = {
+      .role = TUSB_ROLE_DEVICE,
+      .speed = TUD_OPT_HIGH_SPEED ? TUSB_SPEED_HIGH : TUSB_SPEED_FULL,
+  };
+  tusb_init(0, &rh_init);
 
   usb_hardware_init();
 

src/arduino/ports/rp2040/Adafruit_TinyUSB_rp2040.cpp

@@ -98,7 +98,11 @@ static void usb_task_trigger_irq(void) { irq_set_pending(USB_TASK_IRQ); }
 void TinyUSB_Port_InitDevice(uint8_t rhport) {
   mutex_init(&__usb_mutex);
 
-  tud_init(rhport);
+  const tusb_rhport_init_t rh_init = {
+      .role = TUSB_ROLE_DEVICE,
+      .speed = TUSB_SPEED_FULL,
+  };
+  tusb_init(rhport, &rh_init);
 
   // soft irq for task runner
 #if (PICO_SDK_VERSION_MAJOR * 100 + PICO_SDK_VERSION_MINOR) >= 104

src/arduino/ports/samd/Adafruit_TinyUSB_samd.cpp

@@ -113,7 +113,11 @@ void TinyUSB_Port_InitDevice(uint8_t rhport) {
 #endif
 
   // Init port 0 as device
-  tud_init(0);
+  const tusb_rhport_init_t rh_init = {
+      .role = TUSB_ROLE_DEVICE,
+      .speed = TUSB_SPEED_FULL,
+  };
+  tusb_init(0, &rh_init);
 }
 
 void TinyUSB_Port_EnterDFU(void) {

src/arduino/ports/stm32/Adafruit_TinyUSB_stm32.cpp

@@ -80,7 +80,11 @@ void TinyUSB_Port_InitDevice(uint8_t rhport) {
   USB_OTG_FS->GCCFG &= ~USB_OTG_GCCFG_VBUSASEN;
 
   // Initialize TinyUSB device stack
-  tud_init(rhport);
+  const tusb_rhport_init_t rh_init = {
+      .role = TUSB_ROLE_DEVICE,
+      .speed = TUD_OPT_HIGH_SPEED ? TUSB_SPEED_HIGH : TUSB_SPEED_FULL,
+  };
+  tusb_init(rhport, &rh_init);
 }
 
 void TinyUSB_Port_EnterDFU(void) {