Intel IXP400 manual IxUSB API Interfaces, IxUSB Setup Requests

Intel® IXP400 Software

Access-Layer Components: USB Access (ixUSB) API

22.4ixUSB API Interfaces

Table 59. API interfaces Available for Access Layer

API	Description
ixUSBDriverInit	Initialize driver and USB Device Controller.
ixUSBDeviceEnable	Enable or disable the device.
ixUSBEndpointStall	Enable or disable endpoint stall.
ixUSBEndpointClear	Free all Rx/Tx buffers associated with an endpoint.
ixUSBSignalResume	Trigger signal resuming on the bus.
ixUSBFrameCounterGet	Retrieve the 11-bit frame counter.
ixUSBReceiveCallbackRegister	Register a data-receive callback.
ixUSBSetupCallbackRegister	Register a setup-receive callback.
ixUSBBufferSubmit	Submit a buffer for transmit.
ixUSBBufferCancel	Cancel a buffer previously submitted for transmitting.
ixUSBEventCallbackRegister	Register an event callback.
ixUSBIsEndpointStalled	Retrieve an endpoint's stall status.
ixUSBStatisticsShow	Display device state and statistics.
ixUSBErrorStringGet	Convert an error code into a human-readable string error message.
ixUSBEndpointInfoShow	Display endpoint information table.

The ixUSB API components operate within a callback architecture. Initial device setup and configuration is controlled through the callback registered during the ixUSBSetupCallbackRegister function. Data reception occurs through the callback registered during the ixUSBReceiveCallbackRegister function. Special events are signalled to the callback registered during the ixUSBEventCallbackRegister function.

Prior to using any other ixUSB API, the ixUSB client must initialize the controller with the ixUSBDriverInit API call. After this call the driver is in a disabled state. The call to ixUSBDeviceEnable allows data, setup, and configuration transmissions to flow.

22.4.1ixUSB Setup Requests

The UDC’s control, status, and data registers are used only to control and monitor the transmit and receive FIFOs for endpoints 1 - 15. All other UDC configuration and status reporting are controlled by the host, via the USB, using device requests that are sent as control transactions to endpoint 0. Each data packet of a setup stage to endpoint 0 is 8 bytes long and specifies:

•Data transfer direction

—Host to device

—Device to host

April 2005	IXP400 Software Version 2.0	Programmer’s Guide
302	Document Number: 252539, Revision: 007