struct usb_host_endpoint — host-side endpoint descriptor and queue
struct usb_host_endpoint {
  struct usb_endpoint_descriptor desc;
  struct usb_ss_ep_comp_descriptor ss_ep_comp;
  struct list_head urb_list;
  void * hcpriv;
  struct ep_device * ep_dev;
  unsigned char * extra;
  int extralen;
  int enabled;
  int streams;
};  descriptor for this endpoint, wMaxPacketSize in native byteorder
SuperSpeed companion descriptor for this endpoint
urbs queued to this endpoint; maintained by usbcore
for use by HCD; typically holds hardware dma queue head (QH) with one or more transfer descriptors (TDs) per urb
ep_device for sysfs info
descriptors following this endpoint in the configuration
how many bytes of “extra” are valid
URBs may be submitted to this endpoint
number of USB-3 streams allocated on the endpoint