nuttx/Documentation/components/drivers/special/usbdev.rst

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=======================
USB Device-Side Drivers
=======================
- ``include/nuttx/usb/usbdev.h``. All structures and APIs
needed to work with USB device-side drivers are provided in
this header file.
- ``include/nuttx/usb/usbdev_trace.h``. Declarations needed
to work with the NuttX USB device driver trace capability. That
USB trace capability is detailed in `separate
document <UsbTrace.html>`__.
- ``struct usbdev_s``. Each USB device controller driver must
implement an instance of ``struct usbdev_s``. This structure is
defined in ``include/nuttx/usb/usbdev.h``.
**Examples**: ``arch/arm/src/dm320/dm320_usbdev.c``,
``arch/arm/src/lpc17xx_40xx/lpc17_40_usbdev.c``,
``arch/arm/src/lpc214x/lpc214x_usbdev.c``,
``arch/arm/src/lpc313x/lpc313x_usbdev.c``, and
``arch/arm/src/stm32/stm32_usbdev.c``.
- ``struct usbdevclass_driver_s``. Each USB device class
driver must implement an instance of
``struct usbdevclass_driver_s``. This structure is also defined
in ``include/nuttx/usb/usbdev.h``.
**Examples**: ``drivers/usbdev/pl2303.c`` and
``drivers/usbdev/usbmsc.c``
- **Binding USB Device-Side Drivers**. USB device-side controller
drivers are not normally directly accessed by user code, but
are usually bound to another, higher level USB device class
driver. The class driver is then configured to export the USB
device functionality. In general, the binding sequence is:
#. Each USB device class driver includes an initialization
entry point that is called from the application at
initialization time.
**Examples**: The function ``usbdev_serialinitialize()`` in
the file ``drivers/usbdev/pl2303.c`` and the function
in the file ``drivers/usbdev/usbmsc.c``
#. These initialization functions called the driver API,
``usbdev_register()``. This driver function will *bind* the
USB class driver to the USB device controller driver,
completing the initialization.