/*      $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 ([email protected]).
*
* 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;
}