/*      $NetBSD: umct.c,v 1.43 2021/08/07 16:19:17 thorpej Exp $        */
/*
 * Copyright (c) 2001 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Ichiro FUKUHARA (ichiro@ichiro.org).
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*
 * MCT USB-RS232 Interface Controller
 * http://www.mct.com.tw/prod/rs232.html
 * http://www.dlink.com/products/usb/dsbs25
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: umct.c,v 1.43 2021/08/07 16:19:17 thorpej Exp $");

#ifdef _KERNEL_OPT
#include "opt_usb.h"
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/ioctl.h>
#include <sys/conf.h>
#include <sys/tty.h>
#include <sys/file.h>
#include <sys/select.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/device.h>
#include <sys/poll.h>

#include <dev/usb/usb.h>
#include <dev/usb/usbcdc.h>

#include <dev/usb/usbdi.h>
#include <dev/usb/usbdi_util.h>
#include <dev/usb/usbdevs.h>
#include <dev/usb/usb_quirks.h>

#include <dev/usb/ucomvar.h>
#include <dev/usb/umct.h>

#ifdef UMCT_DEBUG
#define DPRINTFN(n, x)  if (umctdebug > (n)) printf x
int     umctdebug = 0;
#else
#define DPRINTFN(n, x)
#endif
#define DPRINTF(x) DPRINTFN(0, x)

#define UMCT_CONFIG_INDEX       0
#define UMCT_IFACE_INDEX        0

struct  umct_softc {
        device_t                sc_dev;         /* base device */
        struct usbd_device *    sc_udev;        /* USB device */
        struct usbd_interface * sc_iface;       /* interface */
        int                     sc_iface_number;        /* interface number */
        uint16_t                sc_product;

        int                     sc_intr_number; /* interrupt number */
        struct usbd_pipe *      sc_intr_pipe;   /* interrupt pipe */
        u_char                  *sc_intr_buf;   /* interrupt buffer */
        int                     sc_isize;

        usb_cdc_line_state_t    sc_line_state;  /* current line state */
        u_char                  sc_dtr;         /* current DTR state */
        u_char                  sc_rts;         /* current RTS state */
        u_char                  sc_break;       /* set break */

        u_char                  sc_status;

        device_t                sc_subdev;      /* ucom device */

        bool                    sc_dying;       /* disconnecting */

        u_char                  sc_lsr;         /* Local status register */
        u_char                  sc_msr;         /* umct status register */

        u_int                   last_lcr;       /* keep lcr register */
};

/*
 * These are the maximum number of bytes transferred per frame.
 * The output buffer size cannot be increased due to the size encoding.
 */
#define UMCTIBUFSIZE 256
#define UMCTOBUFSIZE 256

static  void umct_init(struct umct_softc *);
static  void umct_set_baudrate(struct umct_softc *, u_int);
static  void umct_set_lcr(struct umct_softc *, u_int);
static  void umct_intr(struct usbd_xfer *, void *, usbd_status);

static  void umct_set(void *, int, int, int);
static  void umct_dtr(struct umct_softc *, int);
static  void umct_rts(struct umct_softc *, int);
static  void umct_break(struct umct_softc *, int);
static  void umct_set_line_state(struct umct_softc *);
static  void umct_get_status(void *, int, u_char *, u_char *);
static  int  umct_param(void *, int, struct termios *);
static  int  umct_open(void *, int);
static  void umct_close(void *, int);

static const struct     ucom_methods umct_methods = {
        .ucom_get_status = umct_get_status,
        .ucom_set = umct_set,
        .ucom_param = umct_param,
        .ucom_open = umct_open,
        .ucom_close = umct_close,
};

static const struct usb_devno umct_devs[] = {
        /* MCT USB-232 Interface Products */
        { USB_VENDOR_MCT, USB_PRODUCT_MCT_USB232 },
        /* Sitecom USB-232 Products */
        { USB_VENDOR_MCT, USB_PRODUCT_MCT_SITECOM_USB232 },
        /* D-Link DU-H3SP USB BAY Hub Products */
        { USB_VENDOR_MCT, USB_PRODUCT_MCT_DU_H3SP_USB232 },
        /* BELKIN F5U109 */
        { USB_VENDOR_BELKIN, USB_PRODUCT_BELKIN_F5U109 },
};
#define umct_lookup(v, p) usb_lookup(umct_devs, v, p)

static int      umct_match(device_t, cfdata_t, void *);
static void     umct_attach(device_t, device_t, void *);
static void     umct_childdet(device_t, device_t);
static int      umct_detach(device_t, int);

CFATTACH_DECL2_NEW(umct, sizeof(struct umct_softc), umct_match,
    umct_attach, umct_detach, NULL, NULL, umct_childdet);

static int
umct_match(device_t parent, cfdata_t match, void *aux)
{
        struct usb_attach_arg *uaa = aux;

        return umct_lookup(uaa->uaa_vendor, uaa->uaa_product) != NULL ?
                UMATCH_VENDOR_PRODUCT : UMATCH_NONE;
}

static void
umct_attach(device_t parent, device_t self, void *aux)
{
        struct umct_softc *sc = device_private(self);
        struct usb_attach_arg *uaa = aux;
        struct usbd_device *dev = uaa->uaa_device;
        usb_config_descriptor_t *cdesc;
        usb_interface_descriptor_t *id;
        usb_endpoint_descriptor_t *ed;

        char *devinfop;
        usbd_status err;
        int i;
        struct ucom_attach_args ucaa;

        sc->sc_dev = self;
        sc->sc_dying = false;

        aprint_naive("\n");
        aprint_normal("\n");

        devinfop = usbd_devinfo_alloc(dev, 0);
        aprint_normal_dev(self, "%s\n", devinfop);
        usbd_devinfo_free(devinfop);

        sc->sc_udev = dev;
        sc->sc_product = uaa->uaa_product;

        DPRINTF(("\n\numct attach: sc=%p\n", sc));

        /* initialize endpoints */
        ucaa.ucaa_bulkin = ucaa.ucaa_bulkout = -1;
        sc->sc_intr_number = -1;
        sc->sc_intr_pipe = NULL;

        /* Move the device into the configured state. */
        err = usbd_set_config_index(dev, UMCT_CONFIG_INDEX, 1);
        if (err) {
                aprint_error_dev(self, "failed to set configuration, err=%s\n",
                    usbd_errstr(err));
                sc->sc_dying = true;
                return;
        }

        /* get the config descriptor */
        cdesc = usbd_get_config_descriptor(sc->sc_udev);

        if (cdesc == NULL) {
                aprint_error_dev(self,
                    "failed to get configuration descriptor\n");
                sc->sc_dying = true;
                return;
        }

        /* get the interface */
        err = usbd_device2interface_handle(dev, UMCT_IFACE_INDEX,
                                                        &sc->sc_iface);
        if (err) {
                aprint_error_dev(self, "failed to get interface, err=%s\n",
                    usbd_errstr(err));
                sc->sc_dying = true;
                return;
        }

        /* Find the bulk{in,out} and interrupt endpoints */

        id = usbd_get_interface_descriptor(sc->sc_iface);
        sc->sc_iface_number = id->bInterfaceNumber;

        for (i = 0; i < id->bNumEndpoints; i++) {
                ed = usbd_interface2endpoint_descriptor(sc->sc_iface, i);
                if (ed == NULL) {
                        aprint_error_dev(self,
                            "no endpoint descriptor for %d\n", i);
                        sc->sc_dying = true;
                        return;
                }

                /*
                 * The Bulkin endpoint is marked as an interrupt. Since
                 * we can't rely on the endpoint descriptor order, we'll
                 * check the wMaxPacketSize field to differentiate.
                 */
                if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_INTERRUPT &&
                    UGETW(ed->wMaxPacketSize) != 0x2) {
                        ucaa.ucaa_bulkin = ed->bEndpointAddress;
                } else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_OUT &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK) {
                        ucaa.ucaa_bulkout = ed->bEndpointAddress;
                } else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_INTERRUPT) {
                        sc->sc_intr_number = ed->bEndpointAddress;
                        sc->sc_isize = UGETW(ed->wMaxPacketSize);
                }
        }

        if (ucaa.ucaa_bulkin == -1) {
                aprint_error_dev(self, "Could not find data bulk in\n");
                sc->sc_dying = true;
                return;
        }

        if (ucaa.ucaa_bulkout == -1) {
                aprint_error_dev(self, "Could not find data bulk out\n");
                sc->sc_dying = true;
                return;
        }

        if (sc->sc_intr_number == -1) {
                aprint_error_dev(self, "Could not find interrupt in\n");
                sc->sc_dying = true;
                return;
        }

        sc->sc_dtr = sc->sc_rts = 0;
        ucaa.ucaa_portno = UCOM_UNK_PORTNO;
        /* ucaa_bulkin, ucaa_bulkout set above */
        ucaa.ucaa_ibufsize = UMCTIBUFSIZE;
        if (sc->sc_product == USB_PRODUCT_MCT_SITECOM_USB232)
                ucaa.ucaa_obufsize = 16; /* device is broken */
        else
                ucaa.ucaa_obufsize = UMCTOBUFSIZE;
        ucaa.ucaa_ibufsizepad = UMCTIBUFSIZE;
        ucaa.ucaa_opkthdrlen = 0;
        ucaa.ucaa_device = dev;
        ucaa.ucaa_iface = sc->sc_iface;
        ucaa.ucaa_methods = &umct_methods;
        ucaa.ucaa_arg = sc;
        ucaa.ucaa_info = NULL;

        umct_init(sc);

        usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev, sc->sc_dev);

        DPRINTF(("umct: in=%#x out=%#x intr=%#x\n",
            ucaa.ucaa_bulkin, ucaa.ucaa_bulkout, sc->sc_intr_number));
        sc->sc_subdev = config_found(self, &ucaa, ucomprint,
            CFARGS(.submatch = ucomsubmatch));

        return;
}

static void
umct_childdet(device_t self, device_t child)
{
        struct umct_softc *sc = device_private(self);

        KASSERT(sc->sc_subdev == child);
        sc->sc_subdev = NULL;
}

static void
umct_close_pipe(struct umct_softc *sc)
{

        if (sc->sc_intr_pipe != NULL) {
                usbd_abort_pipe(sc->sc_intr_pipe);
                usbd_close_pipe(sc->sc_intr_pipe);
                sc->sc_intr_pipe = NULL;
        }
        if (sc->sc_intr_buf != NULL) {
                kmem_free(sc->sc_intr_buf, sc->sc_isize);
                sc->sc_intr_buf = NULL;
        }
}

static int
umct_detach(device_t self, int flags)
{
        struct umct_softc *sc = device_private(self);
        int rv = 0;

        DPRINTF(("umct_detach: sc=%p flags=%d\n", sc, flags));

        sc->sc_dying = true;

        umct_close_pipe(sc);

        if (sc->sc_subdev != NULL) {
                rv = config_detach(sc->sc_subdev, flags);
                sc->sc_subdev = NULL;
        }

        usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev, sc->sc_dev);

        return rv;
}

static void
umct_set_line_state(struct umct_softc *sc)
{
        usb_device_request_t req;
        uByte ls;

        ls = (sc->sc_dtr ? MCR_DTR : 0) |
             (sc->sc_rts ? MCR_RTS : 0);

        DPRINTF(("umct_set_line_state: DTR=%d,RTS=%d,ls=%02x\n",
                        sc->sc_dtr, sc->sc_rts, ls));

        req.bmRequestType = UMCT_SET_REQUEST;
        req.bRequest = REQ_SET_MCR;
        USETW(req.wValue, 0);
        USETW(req.wIndex, sc->sc_iface_number);
        USETW(req.wLength, LENGTH_SET_MCR);

        (void)usbd_do_request(sc->sc_udev, &req, &ls);
}

static void
umct_set(void *addr, int portno, int reg, int onoff)
{
        struct umct_softc *sc = addr;

        if (sc->sc_dying)
                return;

        switch (reg) {
        case UCOM_SET_DTR:
                umct_dtr(sc, onoff);
                break;
        case UCOM_SET_RTS:
                umct_rts(sc, onoff);
                break;
        case UCOM_SET_BREAK:
                umct_break(sc, onoff);
                break;
        default:
                break;
        }
}

void
umct_dtr(struct umct_softc *sc, int onoff)
{

        DPRINTF(("umct_dtr: onoff=%d\n", onoff));

        if (sc->sc_dtr == onoff)
                return;
        sc->sc_dtr = onoff;

        umct_set_line_state(sc);
}

void
umct_rts(struct umct_softc *sc, int onoff)
{
        DPRINTF(("umct_rts: onoff=%d\n", onoff));

        if (sc->sc_rts == onoff)
                return;
        sc->sc_rts = onoff;

        umct_set_line_state(sc);
}

void
umct_break(struct umct_softc *sc, int onoff)
{
        DPRINTF(("umct_break: onoff=%d\n", onoff));

        umct_set_lcr(sc, onoff ? sc->last_lcr | LCR_SET_BREAK :
                     sc->last_lcr);
}

void
umct_set_lcr(struct umct_softc *sc, u_int data)
{
        usb_device_request_t req;
        uByte adata;

        adata = data;
        req.bmRequestType = UMCT_SET_REQUEST;
        req.bRequest = REQ_SET_LCR;
        USETW(req.wValue, 0);
        USETW(req.wIndex, sc->sc_iface_number);
        USETW(req.wLength, LENGTH_SET_LCR);

        (void)usbd_do_request(sc->sc_udev, &req, &adata); /* XXX should check */
}

void
umct_set_baudrate(struct umct_softc *sc, u_int rate)
{
        usb_device_request_t req;
        uDWord arate;
        u_int val;

        if (sc->sc_product == USB_PRODUCT_MCT_SITECOM_USB232 ||
            sc->sc_product == USB_PRODUCT_BELKIN_F5U109) {
                switch (rate) {
                case    300: val = 0x01; break;
                case    600: val = 0x02; break;
                case   1200: val = 0x03; break;
                case   2400: val = 0x04; break;
                case   4800: val = 0x06; break;
                case   9600: val = 0x08; break;
                case  19200: val = 0x09; break;
                case  38400: val = 0x0a; break;
                case  57600: val = 0x0b; break;
                case 115200: val = 0x0c; break;
                default:     val = -1; break;
                }
        } else {
                val = UMCT_BAUD_RATE(rate);
        }
        USETDW(arate, val);

        req.bmRequestType = UMCT_SET_REQUEST;
        req.bRequest = REQ_SET_BAUD_RATE;
        USETW(req.wValue, 0);
        USETW(req.wIndex, sc->sc_iface_number);
        USETW(req.wLength, LENGTH_BAUD_RATE);

        (void)usbd_do_request(sc->sc_udev, &req, arate); /* XXX should check */
}

static void
umct_init(struct umct_softc *sc)
{
        umct_set_baudrate(sc, 9600);
        umct_set_lcr(sc, LCR_DATA_BITS_8 | LCR_PARITY_NONE | LCR_STOP_BITS_1);
}

static int
umct_param(void *addr, int portno, struct termios *t)
{
        struct umct_softc *sc = addr;
        u_int data = 0;

        DPRINTF(("umct_param: sc=%p BAUDRATE=%d\n", sc, t->c_ospeed));

        if (sc->sc_dying)
                return EIO;

        if (ISSET(t->c_cflag, CSTOPB))
                data |= LCR_STOP_BITS_2;
        else
                data |= LCR_STOP_BITS_1;
        if (ISSET(t->c_cflag, PARENB)) {
                if (ISSET(t->c_cflag, PARODD))
                        data |= LCR_PARITY_ODD;
                else
                        data |= LCR_PARITY_EVEN;
        } else
                data |= LCR_PARITY_NONE;
        switch (ISSET(t->c_cflag, CSIZE)) {
        case CS5:
                data |= LCR_DATA_BITS_5;
                break;
        case CS6:
                data |= LCR_DATA_BITS_6;
                break;
        case CS7:
                data |= LCR_DATA_BITS_7;
                break;
        case CS8:
                data |= LCR_DATA_BITS_8;
                break;
        }

        umct_set_baudrate(sc, t->c_ospeed);

        sc->last_lcr = data;
        umct_set_lcr(sc, data);

        return 0;
}

int
umct_open(void *addr, int portno)
{
        struct umct_softc *sc = addr;
        int err, lcr_data;

        DPRINTF(("umct_open: sc=%p\n", sc));

        if (sc->sc_dying)
                return EIO;

        /* initialize LCR */
        lcr_data = LCR_DATA_BITS_8 | LCR_PARITY_NONE |
            LCR_STOP_BITS_1;
        umct_set_lcr(sc, lcr_data);

        if (sc->sc_intr_number != -1 && sc->sc_intr_pipe == NULL) {
                sc->sc_status = 0; /* clear status bit */
                sc->sc_intr_buf = kmem_alloc(sc->sc_isize, KM_SLEEP);
                err = usbd_open_pipe_intr(sc->sc_iface, sc->sc_intr_number,
                        USBD_SHORT_XFER_OK, &sc->sc_intr_pipe, sc,
                        sc->sc_intr_buf, sc->sc_isize,
                        umct_intr, USBD_DEFAULT_INTERVAL);
                if (err) {
                        DPRINTF(("%s: cannot open interrupt pipe (addr %d)\n",
                                device_xname(sc->sc_dev), sc->sc_intr_number));
                        return EIO;
                }
        }

        return 0;
}

void
umct_close(void *addr, int portno)
{
        struct umct_softc *sc = addr;

        DPRINTF(("umct_close: close\n"));

        if (sc->sc_dying)
                return;
        umct_close_pipe(sc);
}

void
umct_intr(struct usbd_xfer *xfer, void *priv,
    usbd_status status)
{
        struct umct_softc *sc = priv;
        u_char *tbuf = sc->sc_intr_buf;
        u_char mstatus;

        if (sc->sc_dying)
                return;

        if (status != USBD_NORMAL_COMPLETION) {
                if (status == USBD_NOT_STARTED || status == USBD_CANCELLED)
                        return;

                DPRINTF(("%s: abnormal status: %s\n", device_xname(sc->sc_dev),
                        usbd_errstr(status)));
                usbd_clear_endpoint_stall_async(sc->sc_intr_pipe);
                return;
        }

        DPRINTF(("%s: umct status = MSR:%02x, LSR:%02x\n",
                 device_xname(sc->sc_dev), tbuf[0],tbuf[1]));

        sc->sc_lsr = sc->sc_msr = 0;
        mstatus = tbuf[0];
        if (ISSET(mstatus, MSR_DSR))
                sc->sc_msr |= UMSR_DSR;
        if (ISSET(mstatus, MSR_DCD))
                sc->sc_msr |= UMSR_DCD;
        ucom_status_change(device_private(sc->sc_subdev));
}

void
umct_get_status(void *addr, int portno, u_char *lsr, u_char *msr)
{
        struct umct_softc *sc = addr;

        DPRINTF(("umct_get_status:\n"));

        if (sc->sc_dying)
                return;

        *lsr = sc->sc_lsr;
        *msr = sc->sc_msr;
}