/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2014 Leon Dang <ldang@nahannisys.com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */

#ifndef _USB_EMUL_H_
#define _USB_EMUL_H_

#include <stdlib.h>
#include <sys/linker_set.h>
#include <pthread.h>

#define	USB_MAX_XFER_BLOCKS	8

#define	USB_XFER_OUT		0
#define	USB_XFER_IN		1


struct usb_hci;
struct usb_device_request;
struct usb_data_xfer;
struct vm_snapshot_meta;

/* Device emulation handlers */
struct usb_devemu {
	char	*ue_emu;	/* name of device emulation */
	int	ue_usbver;	/* usb version: 2 or 3 */
	int	ue_usbspeed;	/* usb device speed */

	/* instance creation */
	void	*(*ue_init)(struct usb_hci *hci, char *opt);

	/* handlers */
	int	(*ue_request)(void *sc, struct usb_data_xfer *xfer);
	int	(*ue_data)(void *sc, struct usb_data_xfer *xfer, int dir,
	                   int epctx);
	int	(*ue_reset)(void *sc);
	int	(*ue_remove)(void *sc);
	int	(*ue_stop)(void *sc);
	int	(*ue_snapshot)(void *scarg, struct vm_snapshot_meta *meta);
};
#define	USB_EMUL_SET(x)		DATA_SET(usb_emu_set, x);

/*
 * USB device events to notify HCI when state changes
 */
enum hci_usbev {
	USBDEV_ATTACH,
	USBDEV_RESET,
	USBDEV_STOP,
	USBDEV_REMOVE,
};

/* usb controller, ie xhci, ehci */
struct usb_hci {
	int	(*hci_intr)(struct usb_hci *hci, int epctx);
	int	(*hci_event)(struct usb_hci *hci, enum hci_usbev evid,
		             void *param);
	void	*hci_sc;			/* private softc for hci */

	/* controller managed fields */
	int	hci_address;
	int	hci_port;
};

/*
 * Each xfer block is mapped to the hci transfer block.
 * On input into the device handler, blen is set to the lenght of buf.
 * The device handler is to update blen to reflect on the residual size
 * of the buffer, i.e. len(buf) - len(consumed).
 */
struct usb_data_xfer_block {
	void	*buf;			/* IN or OUT pointer */
	int	blen;			/* in:len(buf), out:len(remaining) */
	int	bdone;			/* bytes transferred */
	uint32_t processed;		/* device processed this + errcode */
	void	*hci_data;		/* HCI private reference */
	int	ccs;
	uint32_t streamid;
	uint64_t trbnext;		/* next TRB guest address */
};

struct usb_data_xfer {
	struct usb_data_xfer_block data[USB_MAX_XFER_BLOCKS];
	struct usb_device_request *ureq; 	/* setup ctl request */
	int	ndata;				/* # of data items */
	int	head;
	int	tail;
	pthread_mutex_t mtx;
};

enum USB_ERRCODE {
	USB_ACK,
	USB_NAK,
	USB_STALL,
	USB_NYET,
	USB_ERR,
	USB_SHORT
};

#define	USB_DATA_GET_ERRCODE(x)		(x)->processed >> 8
#define	USB_DATA_SET_ERRCODE(x,e)	do {				\
			(x)->processed = ((x)->processed & 0xFF) | (e << 8); \
		} while (0)

#define	USB_DATA_OK(x,i)	((x)->data[(i)].buf != NULL)

#define	USB_DATA_XFER_INIT(x)	do {					\
			memset((x), 0, sizeof(*(x)));			\
			pthread_mutex_init(&((x)->mtx), NULL);		\
		} while (0)

#define	USB_DATA_XFER_RESET(x)	do {					\
			memset((x)->data, 0, sizeof((x)->data));	\
			(x)->ndata = 0;					\
			(x)->head = (x)->tail = 0;			\
		} while (0)

#define	USB_DATA_XFER_LOCK(x)	do {					\
			pthread_mutex_lock(&((x)->mtx));		\
		} while (0)

#define	USB_DATA_XFER_UNLOCK(x)	do {					\
			pthread_mutex_unlock(&((x)->mtx));		\
		} while (0)

struct usb_devemu *usb_emu_finddev(char *name);

struct usb_data_xfer_block *usb_data_xfer_append(struct usb_data_xfer *xfer,
                          void *buf, int blen, void *hci_data, int ccs);


#endif /* _USB_EMUL_H_ */