USBD_ValidateConfigurationDescriptor function

Description

The USBD_ValidateConfigurationDescriptor routine validates all descriptors returned by a device in its response to a configuration descriptor request.

Parameters

ConfigDesc [in]

Pointer to a configuration descriptor that includes all interface, endpoint, vendor, and class-specific descriptors retrieved from a USB device.

BufferLength [in]

Size, in bytes, of the configuration descriptor being validated.

Level [in]

Level of validation to be performed. The following are valid values:

• 1-Basic validation of the configuration descriptor header.
• 2-Full validation of the configuration descriptor including checking for invalid endpoint addresses, interface numbers, descriptor structures, interface alternate settings, number of interfaces and bLength fields of all descriptors.
• 3-In addition to the validation for levels 1 and 2, level 3 validates plus validates the number of endpoints in each interface, enforces the USB specification's descriptor bLength sizes, and verifies that all interface numbers are in sequential order.

Offset [out]

Offset within configuration descriptor where validation failed. Only valid when a status other than USBD_STATUS_SUCCESS is returned.

Tag [in, optional]

Pool tag used by USBD_ValidateConfigurationDescriptor when allocating memory.

Return value

USBD_STATUS_SUCCESS, or appropriate USBD error code if validation failed.

See also

USB device driver programming reference