/*      $OpenBSD: moscom.c,v 1.26 2024/05/23 03:21:09 jsg Exp $ */

/*
 * Copyright (c) 2006 Jonathan Gray <jsg@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/tty.h>
#include <sys/device.h>

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

#include <dev/usb/ucomvar.h>

#define MOSCOMBUFSZ             256
#define MOSCOM_IFACE_NO         0

#define MOSCOM_READ             0x0d
#define MOSCOM_WRITE            0x0e
#define MOSCOM_UART_REG         0x0300
#define MOSCOM_VEND_REG         0x0000

#define MOSCOM_TXBUF            0x00    /* Write */
#define MOSCOM_RXBUF            0x00    /* Read */
#define MOSCOM_INT              0x01
#define MOSCOM_FIFO             0x02    /* Write */
#define MOSCOM_ISR              0x02    /* Read */
#define MOSCOM_LCR              0x03
#define MOSCOM_MCR              0x04
#define MOSCOM_LSR              0x05
#define MOSCOM_MSR              0x06
#define MOSCOM_SCRATCH          0x07
#define MOSCOM_DIV_LO           0x08
#define MOSCOM_DIV_HI           0x09
#define MOSCOM_EFR              0x0a
#define MOSCOM_XON1             0x0b
#define MOSCOM_XON2             0x0c
#define MOSCOM_XOFF1            0x0d
#define MOSCOM_XOFF2            0x0e

#define MOSCOM_BAUDLO           0x00
#define MOSCOM_BAUDHI           0x01

#define MOSCOM_INT_RXEN         0x01
#define MOSCOM_INT_TXEN         0x02
#define MOSCOM_INT_RSEN         0x04    
#define MOSCOM_INT_MDMEM        0x08
#define MOSCOM_INT_SLEEP        0x10
#define MOSCOM_INT_XOFF         0x20
#define MOSCOM_INT_RTS          0x40    

#define MOSCOM_FIFO_EN          0x01
#define MOSCOM_FIFO_RXCLR       0x02
#define MOSCOM_FIFO_TXCLR       0x04
#define MOSCOM_FIFO_DMA_BLK     0x08
#define MOSCOM_FIFO_TXLVL_MASK  0x30
#define MOSCOM_FIFO_TXLVL_8     0x00
#define MOSCOM_FIFO_TXLVL_16    0x10
#define MOSCOM_FIFO_TXLVL_32    0x20
#define MOSCOM_FIFO_TXLVL_56    0x30
#define MOSCOM_FIFO_RXLVL_MASK  0xc0
#define MOSCOM_FIFO_RXLVL_8     0x00
#define MOSCOM_FIFO_RXLVL_16    0x40
#define MOSCOM_FIFO_RXLVL_56    0x80
#define MOSCOM_FIFO_RXLVL_80    0xc0

#define MOSCOM_ISR_MDM          0x00
#define MOSCOM_ISR_NONE         0x01
#define MOSCOM_ISR_TX           0x02
#define MOSCOM_ISR_RX           0x04
#define MOSCOM_ISR_LINE         0x06
#define MOSCOM_ISR_RXTIMEOUT    0x0c
#define MOSCOM_ISR_RX_XOFF      0x10
#define MOSCOM_ISR_RTSCTS       0x20
#define MOSCOM_ISR_FIFOEN       0xc0

#define MOSCOM_LCR_DBITS(x)     (x - 5)
#define MOSCOM_LCR_STOP_BITS_1  0x00
#define MOSCOM_LCR_STOP_BITS_2  0x04    /* 2 if 6-8 bits/char or 1.5 if 5 */
#define MOSCOM_LCR_PARITY_NONE  0x00
#define MOSCOM_LCR_PARITY_ODD   0x08
#define MOSCOM_LCR_PARITY_EVEN  0x18
#define MOSCOM_LCR_BREAK        0x40
#define MOSCOM_LCR_DIVLATCH_EN  0x80

#define MOSCOM_MCR_DTR          0x01
#define MOSCOM_MCR_RTS          0x02
#define MOSCOM_MCR_LOOP         0x04
#define MOSCOM_MCR_INTEN        0x08
#define MOSCOM_MCR_LOOPBACK     0x10
#define MOSCOM_MCR_XONANY       0x20
#define MOSCOM_MCR_IRDA_EN      0x40
#define MOSCOM_MCR_BAUD_DIV4    0x80

#define MOSCOM_LSR_RXDATA       0x01
#define MOSCOM_LSR_RXOVER       0x02
#define MOSCOM_LSR_RXPAR_ERR    0x04
#define MOSCOM_LSR_RXFRM_ERR    0x08
#define MOSCOM_LSR_RXBREAK      0x10
#define MOSCOM_LSR_TXEMPTY      0x20
#define MOSCOM_LSR_TXALLEMPTY   0x40
#define MOSCOM_LSR_TXFIFO_ERR   0x80

#define MOSCOM_MSR_CTS_CHG      0x01
#define MOSCOM_MSR_DSR_CHG      0x02
#define MOSCOM_MSR_RI_CHG       0x04
#define MOSCOM_MSR_CD_CHG       0x08
#define MOSCOM_MSR_CTS          0x10
#define MOSCOM_MSR_RTS          0x20
#define MOSCOM_MSR_RI           0x40
#define MOSCOM_MSR_CD           0x80

#define MOSCOM_BAUD_REF         115200

struct moscom_softc {
        struct device            sc_dev;
        struct usbd_device      *sc_udev;
        struct usbd_interface   *sc_iface;
        struct device           *sc_subdev;

        u_char                   sc_msr;
        u_char                   sc_lsr;
        u_char                   sc_lcr;
};

void    moscom_set(void *, int, int, int);
int     moscom_param(void *, int, struct termios *);
int     moscom_open(void *, int);
int     moscom_cmd(struct moscom_softc *, int, int);    

const struct ucom_methods moscom_methods = {
        NULL,
        moscom_set,
        moscom_param,
        NULL,
        moscom_open,
        NULL,
        NULL,
        NULL,
};

static const struct usb_devno moscom_devs[] = {
        { USB_VENDOR_MOSCHIP,           USB_PRODUCT_MOSCHIP_MCS7703 }
};

int moscom_match(struct device *, void *, void *);
void moscom_attach(struct device *, struct device *, void *);
int moscom_detach(struct device *, int);

struct cfdriver moscom_cd = {
        NULL, "moscom", DV_DULL
};

const struct cfattach moscom_ca = {
        sizeof(struct moscom_softc), moscom_match, moscom_attach, moscom_detach
};

int
moscom_match(struct device *parent, void *match, void *aux)
{
        struct usb_attach_arg *uaa = aux;

        if (uaa->iface == NULL)
                return UMATCH_NONE;

        return (usb_lookup(moscom_devs, uaa->vendor, uaa->product) != NULL) ?
            UMATCH_VENDOR_PRODUCT : UMATCH_NONE;
}

void
moscom_attach(struct device *parent, struct device *self, void *aux)
{
        struct moscom_softc *sc = (struct moscom_softc *)self;
        struct usb_attach_arg *uaa = aux;
        struct ucom_attach_args uca;
        usb_interface_descriptor_t *id;
        usb_endpoint_descriptor_t *ed;
        usbd_status error;
        int i;

        bzero(&uca, sizeof(uca));
        sc->sc_udev = uaa->device;

        /* get the first interface handle */
        error = usbd_device2interface_handle(sc->sc_udev, MOSCOM_IFACE_NO,
            &sc->sc_iface);
        if (error != 0) {
                printf("%s: could not get interface handle\n",
                    sc->sc_dev.dv_xname);
                usbd_deactivate(sc->sc_udev);
                return;
        }

        id = usbd_get_interface_descriptor(sc->sc_iface);

        uca.bulkin = uca.bulkout = -1;
        for (i = 0; i < id->bNumEndpoints; i++) {
                ed = usbd_interface2endpoint_descriptor(sc->sc_iface, i);
                if (ed == NULL) {
                        printf("%s: no endpoint descriptor found for %d\n",
                            sc->sc_dev.dv_xname, i);
                        usbd_deactivate(sc->sc_udev);
                        return;
                }

                if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK)
                        uca.bulkin = ed->bEndpointAddress;
                else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_OUT &&
                    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK)
                        uca.bulkout = ed->bEndpointAddress;
        }

        if (uca.bulkin == -1 || uca.bulkout == -1) {
                printf("%s: missing endpoint\n", sc->sc_dev.dv_xname);
                usbd_deactivate(sc->sc_udev);
                return;
        }

        uca.ibufsize = MOSCOMBUFSZ;
        uca.obufsize = MOSCOMBUFSZ;
        uca.ibufsizepad = MOSCOMBUFSZ;
        uca.opkthdrlen = 0;
        uca.device = sc->sc_udev;
        uca.iface = sc->sc_iface;
        uca.methods = &moscom_methods;
        uca.arg = sc;
        uca.info = NULL;
        
        sc->sc_subdev = config_found_sm(self, &uca, ucomprint, ucomsubmatch);
}

int
moscom_detach(struct device *self, int flags)
{
        struct moscom_softc *sc = (struct moscom_softc *)self;
        int rv = 0;

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

        return (rv);
}

int
moscom_open(void *vsc, int portno)
{
        struct moscom_softc *sc = vsc;
        usb_device_request_t req;

        if (usbd_is_dying(sc->sc_udev))
                return (EIO);

        /* Purge FIFOs or odd things happen */
        if (moscom_cmd(sc, MOSCOM_FIFO, 0x00) != 0)
                return (EIO);
        
        if (moscom_cmd(sc, MOSCOM_FIFO, MOSCOM_FIFO_EN |
            MOSCOM_FIFO_RXCLR | MOSCOM_FIFO_TXCLR |
            MOSCOM_FIFO_DMA_BLK | MOSCOM_FIFO_RXLVL_MASK) != 0) 
                return (EIO);

        /* Magic tell device we're ready for data command */
        req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
        req.bRequest = MOSCOM_WRITE;
        USETW(req.wValue, 0x08);
        USETW(req.wIndex, MOSCOM_INT);
        USETW(req.wLength, 0);
        if (usbd_do_request(sc->sc_udev, &req, NULL) != 0)
                return (EIO);

        return (0);
}

void
moscom_set(void *vsc, int portno, int reg, int onoff)
{
        struct moscom_softc *sc = vsc;
        int val;

        switch (reg) {
        case UCOM_SET_DTR:
                val = onoff ? MOSCOM_MCR_DTR : 0;
                break;
        case UCOM_SET_RTS:
                val = onoff ? MOSCOM_MCR_RTS : 0;
                break;
        case UCOM_SET_BREAK:
                val = sc->sc_lcr;
                if (onoff)
                        val |= MOSCOM_LCR_BREAK;
                moscom_cmd(sc, MOSCOM_LCR, val);
                return;
        default:
                return;
        }

        moscom_cmd(sc, MOSCOM_MCR, val);
}

int
moscom_param(void *vsc, int portno, struct termios *t)
{
        struct moscom_softc *sc = (struct moscom_softc *)vsc;
        int data;

        if (t->c_ospeed <= 0 || t->c_ospeed > 115200)
                return (EINVAL);

        data = MOSCOM_BAUD_REF / t->c_ospeed;

        if (data == 0 || data > 0xffff)
                return (EINVAL);

        moscom_cmd(sc, MOSCOM_LCR, MOSCOM_LCR_DIVLATCH_EN);
        moscom_cmd(sc, MOSCOM_BAUDLO, data & 0xFF);
        moscom_cmd(sc, MOSCOM_BAUDHI, (data >> 8) & 0xFF);

        if (ISSET(t->c_cflag, CSTOPB))
                data = MOSCOM_LCR_STOP_BITS_2;
        else
                data = MOSCOM_LCR_STOP_BITS_1;
        if (ISSET(t->c_cflag, PARENB)) {
                if (ISSET(t->c_cflag, PARODD))
                        data |= MOSCOM_LCR_PARITY_ODD;
                else
                        data |= MOSCOM_LCR_PARITY_EVEN;
        } else
                data |= MOSCOM_LCR_PARITY_NONE;
        switch (ISSET(t->c_cflag, CSIZE)) {
        case CS5:
                data |= MOSCOM_LCR_DBITS(5);
                break;
        case CS6:
                data |= MOSCOM_LCR_DBITS(6);
                break;
        case CS7:
                data |= MOSCOM_LCR_DBITS(7);
                break;
        case CS8:
                data |= MOSCOM_LCR_DBITS(8);
                break;
        }

        sc->sc_lcr = data;
        moscom_cmd(sc, MOSCOM_LCR, sc->sc_lcr);

#if 0
        /* XXX flow control */
        if (ISSET(t->c_cflag, CRTSCTS))
                /*  rts/cts flow ctl */
        } else if (ISSET(t->c_iflag, IXON|IXOFF)) {
                /*  xon/xoff flow ctl */
        } else {
                /* disable flow ctl */
        }
#endif

        return (0);
}

int
moscom_cmd(struct moscom_softc *sc, int reg, int val)
{
        usb_device_request_t req;
        usbd_status err;
        
        req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
        req.bRequest = MOSCOM_WRITE;
        USETW(req.wValue, val + MOSCOM_UART_REG);
        USETW(req.wIndex, reg);
        USETW(req.wLength, 0);
        err = usbd_do_request(sc->sc_udev, &req, NULL);
        if (err)
                return (EIO);
        else
                return (0);
}