# flutter_usb_serial

Flutter USB serial transport for Android and DriverKit-enabled iPadOS.

## Platforms

- Android uses `usb-serial-for-android` and the normal Android USB permission
  flow.
- iPadOS 16+ uses Swift Package Manager and a user client exposed by a
  USBDriverKit extension embedded in the host app. DriverKit USB support is
  available only on iPads with an M-series chip.

The package contains the SwiftPM client plugin, not a reusable pre-signed
DriverKit extension. Apple provisions USB transport entitlements to the host
app and driver for a specific USB vendor. The host app must:

1. Embed a DriverKit extension whose `IOUserClass` is
   `DaliMasterEspressifUsbDriver`, or adapt the client service name.
2. Add `com.apple.developer.driverkit.communicates-with-drivers` to the app.
3. Sign the extension with `com.apple.developer.driverkit` and a
   `com.apple.developer.driverkit.transport.usb` entitlement approved for its
   USB vendor ID.
4. Enable Swift Package Manager integration for Flutter iOS plugins.

Call `FlutterUsbSerial.isDriverAvailable()` during startup before showing a USB
transport. It returns `true` only when a compatible driver service is loaded.

The DaliMaster host implementation is deliberately restricted to Espressif
vendor ID `0x303A` and the USB Serial/JTAG interface. Serial parameter and modem
line methods are accepted for API compatibility; the ESP USB Serial/JTAG bulk
transport does not use UART baud or line coding.