struct usb

struct usb_ep
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Name

struct usb_ep — device side representation of USB endpoint

Synopsis

struct usb_ep {
  void * driver_data;
  const char * name;
  const struct usb_ep_ops * ops;
  struct list_head ep_list;
  struct usb_ep_caps caps;
  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;
};

Members

void * driver_data: for use by the gadget driver.
const char * name: identifier for the endpoint, such as “ep-a” or “ep9in-bulk”
const struct usb_ep_ops * ops: Function pointers used to access hardware-specific operations.
struct list_head ep_list: the gadget's ep_list holds all of its endpoints
struct usb_ep_caps caps: The structure describing types and directions supported by endoint.
unsigned:16 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.
unsigned:16 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.
unsigned:16 max_streams: The maximum number of streams supported by this EP (0 - 16, actual number is 2^n)
unsigned:2 mult: multiplier, 'mult' value for SS Isoc EPs
unsigned:5 maxburst: the maximum number of bursts supported by this EP (for usb3)
u8 address: used to identify the endpoint when finding descriptor that matches connection speed
const struct usb_endpoint_descriptor * desc: endpoint descriptor. This pointer is set before the endpoint is enabled and remains valid until the endpoint is disabled.
const struct usb_ss_ep_comp_descriptor * comp_desc: In case of SuperSpeed support, this is the endpoint companion descriptor that is used to configure the endpoint

Description

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.