/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * 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.
 */

#ifndef _USB_EMUL_H_
#define _USB_EMUL_H_

#include <sys/nv.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 {
        const 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_probe)(struct usb_hci *hci, nvlist_t *nvl);
        int     (*ue_init)(void *sc);

        /* 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;
        int     hci_speed;
        int     hci_usbver;
};

/*
 * Each xfer block is mapped to the hci transfer block.
 * On input into the device handler, blen is set to the length 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(const 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_ */