struct_usb_ep (9)

struct usb_ep {
  void * driver_data;
  const char * name;
  const struct usb_ep_ops * ops;
  struct list_head ep_list;
  unsigned maxpacket:16;
  unsigned maxpacket_limit:16;
  unsigned max_streams:16;
  unsigned mult:2;
  unsigned maxburst:5;
  u8 address;
  const struct usb_endpoint_descriptor * desc;
  const struct usb_ss_ep_comp_descriptor * comp_desc;
};

driver_data

for use by the gadget driver.

name

identifier for the endpoint, such as “ep-a” or “ep9in-bulk”

ops

Function pointers used to access hardware-specific operations.

ep_list

the gadget's ep_list holds all of its endpoints

maxpacket

The maximum packet size used on this endpoint. The initial value can sometimes be reduced (hardware allowing), according to the endpoint descriptor used to configure the endpoint.

maxpacket_limit

The maximum packet size value which can be handled by this endpoint. It's set once by UDC driver when endpoint is initialized, and should not be changed. Should not be confused with maxpacket.

max_streams

The maximum number of streams supported by this EP (0 - 16, actual number is 2^n)

mult

multiplier, 'mult' value for SS Isoc EPs

maxburst

the maximum number of bursts supported by this EP (for usb3)

address

used to identify the endpoint when finding descriptor that matches connection speed

desc

endpoint descriptor. This pointer is set before the endpoint is enabled and remains valid until the endpoint is disabled.

comp_desc

In case of SuperSpeed support, this is the endpoint companion descriptor that is used to configure the endpoint

the bus controller driver lists all the general purpose endpoints in gadget->ep_list. the control endpoint (gadget->ep0) is not in that list, and is accessed only in response to a driver setup callback.

David Brownell <[email protected]>

Author.