text: /* Copyright 2016 The Chromium OS Authors. All rights reserved.
   * Use of this source code is governed by a BSD-style license that can be
   * found in the LICENSE file.
   */
  
  #ifndef __CROS_EC_USB_DWC_HW_H
  #define __CROS_EC_USB_DWC_HW_H
  
  #include "usb_dwc_registers.h"
  
  /* Helpers for endpoint declaration */
  #define _EP_HANDLER2(num, suffix) CONCAT3(ep_, num, suffix)
  #define _EP_TX_HANDLER(num) _EP_HANDLER2(num, _tx)
  #define _EP_RX_HANDLER(num) _EP_HANDLER2(num, _rx)
  #define _EP_EVENT_HANDLER(num) _EP_HANDLER2(num, _evt)
  /* Used to check function types are correct (attribute alias does not do it) */
  #define _EP_TX_HANDLER_TYPECHECK(num) _EP_HANDLER2(num, _tx_typecheck)
  #define _EP_RX_HANDLER_TYPECHECK(num) _EP_HANDLER2(num, _rx_typecheck)
  #define _EP_EVENT_HANDLER_TYPECHECK(num) _EP_HANDLER2(num, _evt_typecheck)
  
  #define USB_DECLARE_EP(num, tx_handler, rx_handler, evt_handler)  \
  	void _EP_TX_HANDLER(num)(void)				  \
  		__attribute__ ((alias(STRINGIFY(tx_handler))));	  \
  	void _EP_RX_HANDLER(num)(void)                            \
  		__attribute__ ((alias(STRINGIFY(rx_handler))));	  \
  	void _EP_EVENT_HANDLER(num)(enum usb_ep_event evt)	  \
  		__attribute__ ((alias(STRINGIFY(evt_handler))));  \
  	static __unused void					  \
  	(*_EP_TX_HANDLER_TYPECHECK(num))(void) = tx_handler;	  \
  	static __unused void					  \
  	(*_EP_RX_HANDLER_TYPECHECK(num))(void) = rx_handler;	  \
  	static __unused void					  \
  	(*_EP_EVENT_HANDLER_TYPECHECK(num))(enum usb_ep_event evt)\
  			= evt_handler
  
  /* Endpoint callbacks */
  extern void (*usb_ep_tx[]) (void);
  extern void (*usb_ep_rx[]) (void);
  extern void (*usb_ep_event[]) (enum usb_ep_event evt);
  struct usb_setup_packet;
  /* EP0 Interface handler callbacks */
  extern int (*usb_iface_request[]) (struct usb_setup_packet *req);
  
  
  /* True if the HW Rx/OUT FIFO is currently listening. */
  int rx_ep_is_active(uint32_t ep_num);
  
  /* Number of bytes the HW Rx/OUT FIFO has for us.
   *
   * @param ep_num        USB endpoint
   *
   * @returns             number of bytes ready, zero if none.
   */
  int rx_ep_pending(uint32_t ep_num);
  
  /* True if the Tx/IN FIFO can take some bytes from us. */
  int tx_ep_is_ready(uint32_t ep_num);
  
  /* Write packets of data IN to the host.
   *
   * This function uses DMA, so the *data write buffer
   * must persist until the write completion event.
   *
   * @param ep_num        USB endpoint to write
   * @param len           number of bytes to write
   * @param data          pointer of data to write
   *
   * @return              bytes written
   */
  int usb_write_ep(uint32_t ep_num, int len, void *data);
  
  /* Read a packet of data OUT from the host.
   *
   * This function uses DMA, so the *data write buffer
   * must persist until the read completion event.
   *
   * @param ep_num        USB endpoint to read
   * @param len           number of bytes to read
   * @param data          pointer of data to read
   *
   * @return              EC_SUCCESS on success
   */
  int usb_read_ep(uint32_t ep_num, int len, void *data);
  
  /* Tx/IN interrupt handler */
  void usb_epN_tx(uint32_t ep_num);
  
  /* Rx/OUT endpoint interrupt handler */
  void usb_epN_rx(uint32_t ep_num);
  
  /* Reset endpoint HW block. */
  void epN_reset(uint32_t ep_num);
  
  /*
   * Declare any interface-specific control request handlers. These Setup packets
   * arrive on the control endpoint (EP0), but are handled by the interface code.
   * The callback must prepare the EP0 IN or OUT FIFOs and return the number of
   * bytes placed in the IN FIFO. A negative return value will STALL the response
   * (and thus indicate error to the host).
   */
  #define _IFACE_HANDLER(num) CONCAT3(iface_, num, _request)
  #define USB_DECLARE_IFACE(num, handler)				\
  	int _IFACE_HANDLER(num)(struct usb_setup_packet *req)	\
  		__attribute__ ((alias(STRINGIFY(handler))))
  
  #endif	/* __CROS_EC_USB_DWC_HW_H */
  