USB_GADGET_CONFIG_BU(9) 				      Kernel Mode Gadget API					   USB_GADGET_CONFIG_BU(9)

NAME

       usb_gadget_config_buf - builts a complete configuration descriptor

SYNOPSIS

       int usb_gadget_config_buf(const struct usb_config_descriptor * config, void * buf, unsigned length,
				 const struct usb_descriptor_header ** desc);

ARGUMENTS

       config
	   Header for the descriptor, including characteristics such as power requirements and number of interfaces.

       buf
	   Buffer for the resulting configuration descriptor.

       length
	   Length of buffer. If this is not big enough to hold the entire configuration descriptor, an error code will be returned.

       desc
	   Null-terminated vector of pointers to the descriptors (interface, endpoint, etc) defining all functions in this device configuration.

DESCRIPTION

       This copies descriptors into the response buffer, building a descriptor for that configuration. It returns the buffer length or a negative
       status code. The config.wTotalLength field is set to match the length of the result, but other descriptor fields (including power usage and
       interface count) must be set by the caller.

       Gadget drivers could use this when constructing a config descriptor in response to USB_REQ_GET_DESCRIPTOR. They will need to patch the
       resulting bDescriptorType value if USB_DT_OTHER_SPEED_CONFIG is needed.

AUTHOR

       David Brownell <dbrownell@users.sourceforge.net>
	   Author.

COPYRIGHT

Kernel Hackers Manual 3.10					     June 2014						   USB_GADGET_CONFIG_BU(9)