Crate usb_gadget 

This library allows implementation of USB peripherals, so called USB gadgets, on Linux devices that have a USB device controller (UDC). Both, pre-defined USB functions and fully custom implementations of the USB interface are supported.

The following pre-defined USB functions, implemented by kernel drivers, are supported:

• network interface: CDC ECM, ECM subset, EEM, NCM, RNDIS
• serial port: CDC ACM, generic
• human interface device (HID)
• mass-storage device (MSD)
• printer device
• musical instrument digital interface (MIDI)
• audio device: UAC1 and UAC2
• video device (UVC)

In addition fully custom USB functions can be implemented in user-mode Rust code.

Support for OS-specific descriptors and WebUSB is also provided.

Requirements

A USB device controller (UDC) supported by Linux is required.

The Linux kernel configuration options CONFIG_USB_GADGET and CONFIG_USB_CONFIGFS need to be enabled.

root permissions are required to configure USB gadgets and the configfs filesystem needs to be mounted.

Some settings are only supported by newer kernels. Optional settings are only written when set; if left at None, the kernel default is used. Setting an option that is unsupported by the running kernel makes registration fail with an error of kind ErrorKind::Unsupported. The exceptions are OS descriptors and WebUSB, which are skipped with a warning.

Usage

Start defining a USB gadget by calling Gadget::new. When the gadget is fully specified, call Gadget::bind to register it with a USB device controller (UDC).

Modules

function

USB gadget functions.

Structs

Class

USB gadget or interface class.

Config

USB gadget configuration.

Gadget

USB gadget definition.

Id

USB gadget id.

OsDescriptor

USB gadget operating system descriptor.

RegFunction

USB gadget registered with the system.

RegGadget

If this was obtained by calling Gadget::bind, the USB gadget will be unbound and removed when this is dropped.

Strings

USB gadget description strings.

Udc

USB device controller (UDC).

WebUsb

USB gadget WebUSB descriptor.

Enums

Language

USB language id.

Speed

USB speed.

UdcState

USB device controller (UDC) connection state.

UsbVersion

USB version.

WebUsbVersion

WebUSB version.

Constants

GADGET_IOC_MAGIC

USB gadget ioctl magic byte.

Functions

default_udc

The default USB device controller (UDC) in the system by alphabetical sorting.

registered

Get all USB gadgets registered on the system.

remove_all

Remove all USB gadgets defined on the system.

udcs

Gets the available USB device controllers (UDCs) in the system.

unbind_all

Unbind all USB gadgets defined on the system.