/*      $OpenBSD: uark.c,v 1.1 2006/08/14 08:30:22 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.
 */

/*
 * NOTE: all function names beginning like "uark_cfg_" can only
 * be called from within the config thread function !
 */

#include <sys/stdint.h>
#include <sys/stddef.h>
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/types.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/bus.h>
#include <sys/module.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/sysctl.h>
#include <sys/sx.h>
#include <sys/unistd.h>
#include <sys/callout.h>
#include <sys/malloc.h>
#include <sys/priv.h>

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

#define USB_DEBUG_VAR usb_debug
#include <dev/usb/usb_debug.h>
#include <dev/usb/usb_process.h>

#include <dev/usb/serial/usb_serial.h>

#define UARK_BUF_SIZE           1024    /* bytes */

#define UARK_SET_DATA_BITS(x)   ((x) - 5)

#define UARK_PARITY_NONE        0x00
#define UARK_PARITY_ODD         0x08
#define UARK_PARITY_EVEN        0x18

#define UARK_STOP_BITS_1        0x00
#define UARK_STOP_BITS_2        0x04

#define UARK_BAUD_REF           3000000

#define UARK_WRITE              0x40
#define UARK_READ               0xc0

#define UARK_REQUEST            0xfe

#define UARK_CONFIG_INDEX       0
#define UARK_IFACE_INDEX        0

enum {
        UARK_BULK_DT_WR,
        UARK_BULK_DT_RD,
        UARK_N_TRANSFER,
};

struct uark_softc {
        struct ucom_super_softc sc_super_ucom;
        struct ucom_softc sc_ucom;

        struct usb_xfer *sc_xfer[UARK_N_TRANSFER];
        struct usb_device *sc_udev;
        struct mtx sc_mtx;

        uint8_t sc_msr;
        uint8_t sc_lsr;
};

/* prototypes */

static device_probe_t uark_probe;
static device_attach_t uark_attach;
static device_detach_t uark_detach;
static void uark_free_softc(struct uark_softc *);

static usb_callback_t uark_bulk_write_callback;
static usb_callback_t uark_bulk_read_callback;

static void     uark_free(struct ucom_softc *);
static void     uark_start_read(struct ucom_softc *);
static void     uark_stop_read(struct ucom_softc *);
static void     uark_start_write(struct ucom_softc *);
static void     uark_stop_write(struct ucom_softc *);
static int      uark_pre_param(struct ucom_softc *, struct termios *);
static void     uark_cfg_param(struct ucom_softc *, struct termios *);
static void     uark_cfg_get_status(struct ucom_softc *, uint8_t *,
                    uint8_t *);
static void     uark_cfg_set_break(struct ucom_softc *, uint8_t);
static void     uark_cfg_write(struct uark_softc *, uint16_t, uint16_t);
static void     uark_poll(struct ucom_softc *ucom);

static const struct usb_config
        uark_xfer_config[UARK_N_TRANSFER] = {
        [UARK_BULK_DT_WR] = {
                .type = UE_BULK,
                .endpoint = UE_ADDR_ANY,
                .direction = UE_DIR_OUT,
                .bufsize = UARK_BUF_SIZE,
                .flags = {.pipe_bof = 1,.force_short_xfer = 1,},
                .callback = &uark_bulk_write_callback,
        },

        [UARK_BULK_DT_RD] = {
                .type = UE_BULK,
                .endpoint = UE_ADDR_ANY,
                .direction = UE_DIR_IN,
                .bufsize = UARK_BUF_SIZE,
                .flags = {.pipe_bof = 1,.short_xfer_ok = 1,},
                .callback = &uark_bulk_read_callback,
        },
};

static const struct ucom_callback uark_callback = {
        .ucom_cfg_get_status = &uark_cfg_get_status,
        .ucom_cfg_set_break = &uark_cfg_set_break,
        .ucom_cfg_param = &uark_cfg_param,
        .ucom_pre_param = &uark_pre_param,
        .ucom_start_read = &uark_start_read,
        .ucom_stop_read = &uark_stop_read,
        .ucom_start_write = &uark_start_write,
        .ucom_stop_write = &uark_stop_write,
        .ucom_poll = &uark_poll,
        .ucom_free = &uark_free,
};

static device_method_t uark_methods[] = {
        /* Device methods */
        DEVMETHOD(device_probe, uark_probe),
        DEVMETHOD(device_attach, uark_attach),
        DEVMETHOD(device_detach, uark_detach),
        DEVMETHOD_END
};

static driver_t uark_driver = {
        .name = "uark",
        .methods = uark_methods,
        .size = sizeof(struct uark_softc),
};

static const STRUCT_USB_HOST_ID uark_devs[] = {
        {USB_VPI(USB_VENDOR_ARKMICRO, USB_PRODUCT_ARKMICRO_ARK3116, 0)},
};

DRIVER_MODULE(uark, uhub, uark_driver, NULL, NULL);
MODULE_DEPEND(uark, ucom, 1, 1, 1);
MODULE_DEPEND(uark, usb, 1, 1, 1);
MODULE_VERSION(uark, 1);
USB_PNP_HOST_INFO(uark_devs);

static int
uark_probe(device_t dev)
{
        struct usb_attach_arg *uaa = device_get_ivars(dev);

        if (uaa->usb_mode != USB_MODE_HOST) {
                return (ENXIO);
        }
        if (uaa->info.bConfigIndex != 0) {
                return (ENXIO);
        }
        if (uaa->info.bIfaceIndex != UARK_IFACE_INDEX) {
                return (ENXIO);
        }
        return (usbd_lookup_id_by_uaa(uark_devs, sizeof(uark_devs), uaa));
}

static int
uark_attach(device_t dev)
{
        struct usb_attach_arg *uaa = device_get_ivars(dev);
        struct uark_softc *sc = device_get_softc(dev);
        int32_t error;
        uint8_t iface_index;

        device_set_usb_desc(dev);
        mtx_init(&sc->sc_mtx, "uark", NULL, MTX_DEF);
        ucom_ref(&sc->sc_super_ucom);

        sc->sc_udev = uaa->device;

        iface_index = UARK_IFACE_INDEX;
        error = usbd_transfer_setup
            (uaa->device, &iface_index, sc->sc_xfer,
            uark_xfer_config, UARK_N_TRANSFER, sc, &sc->sc_mtx);

        if (error) {
                device_printf(dev, "allocating control USB "
                    "transfers failed\n");
                goto detach;
        }
        /* clear stall at first run */
        mtx_lock(&sc->sc_mtx);
        usbd_xfer_set_stall(sc->sc_xfer[UARK_BULK_DT_WR]);
        usbd_xfer_set_stall(sc->sc_xfer[UARK_BULK_DT_RD]);
        mtx_unlock(&sc->sc_mtx);

        error = ucom_attach(&sc->sc_super_ucom, &sc->sc_ucom, 1, sc,
            &uark_callback, &sc->sc_mtx);
        if (error) {
                DPRINTF("ucom_attach failed\n");
                goto detach;
        }
        ucom_set_pnpinfo_usb(&sc->sc_super_ucom, dev);

        return (0);                     /* success */

detach:
        uark_detach(dev);
        return (ENXIO);                 /* failure */
}

static int
uark_detach(device_t dev)
{
        struct uark_softc *sc = device_get_softc(dev);

        ucom_detach(&sc->sc_super_ucom, &sc->sc_ucom);
        usbd_transfer_unsetup(sc->sc_xfer, UARK_N_TRANSFER);

        device_claim_softc(dev);

        uark_free_softc(sc);

        return (0);
}

UCOM_UNLOAD_DRAIN(uark);

static void
uark_free_softc(struct uark_softc *sc)
{
        if (ucom_unref(&sc->sc_super_ucom)) {
                mtx_destroy(&sc->sc_mtx);
                device_free_softc(sc);
        }
}

static void
uark_free(struct ucom_softc *ucom)
{
        uark_free_softc(ucom->sc_parent);
}

static void
uark_bulk_write_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct uark_softc *sc = usbd_xfer_softc(xfer);
        struct usb_page_cache *pc;
        uint32_t actlen;

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_SETUP:
        case USB_ST_TRANSFERRED:
tr_setup:
                pc = usbd_xfer_get_frame(xfer, 0);
                if (ucom_get_data(&sc->sc_ucom, pc, 0,
                    UARK_BUF_SIZE, &actlen)) {
                        usbd_xfer_set_frame_len(xfer, 0, actlen);
                        usbd_transfer_submit(xfer);
                }
                return;

        default:                        /* Error */
                if (error != USB_ERR_CANCELLED) {
                        /* try to clear stall first */
                        usbd_xfer_set_stall(xfer);
                        goto tr_setup;
                }
                return;
        }
}

static void
uark_bulk_read_callback(struct usb_xfer *xfer, usb_error_t error)
{
        struct uark_softc *sc = usbd_xfer_softc(xfer);
        struct usb_page_cache *pc;
        int actlen;

        usbd_xfer_status(xfer, &actlen, NULL, NULL, NULL);

        switch (USB_GET_STATE(xfer)) {
        case USB_ST_TRANSFERRED:
                pc = usbd_xfer_get_frame(xfer, 0);
                ucom_put_data(&sc->sc_ucom, pc, 0, actlen);

        case USB_ST_SETUP:
tr_setup:
                usbd_xfer_set_frame_len(xfer, 0, usbd_xfer_max_len(xfer));
                usbd_transfer_submit(xfer);
                return;

        default:                        /* Error */
                if (error != USB_ERR_CANCELLED) {
                        /* try to clear stall first */
                        usbd_xfer_set_stall(xfer);
                        goto tr_setup;
                }
                return;
        }
}

static void
uark_start_read(struct ucom_softc *ucom)
{
        struct uark_softc *sc = ucom->sc_parent;

        usbd_transfer_start(sc->sc_xfer[UARK_BULK_DT_RD]);
}

static void
uark_stop_read(struct ucom_softc *ucom)
{
        struct uark_softc *sc = ucom->sc_parent;

        usbd_transfer_stop(sc->sc_xfer[UARK_BULK_DT_RD]);
}

static void
uark_start_write(struct ucom_softc *ucom)
{
        struct uark_softc *sc = ucom->sc_parent;

        usbd_transfer_start(sc->sc_xfer[UARK_BULK_DT_WR]);
}

static void
uark_stop_write(struct ucom_softc *ucom)
{
        struct uark_softc *sc = ucom->sc_parent;

        usbd_transfer_stop(sc->sc_xfer[UARK_BULK_DT_WR]);
}

static int
uark_pre_param(struct ucom_softc *ucom, struct termios *t)
{
        if ((t->c_ospeed < 300) || (t->c_ospeed > 115200))
                return (EINVAL);
        return (0);
}

static void
uark_cfg_param(struct ucom_softc *ucom, struct termios *t)
{
        struct uark_softc *sc = ucom->sc_parent;
        uint32_t speed = t->c_ospeed;
        uint16_t data;

        /*
         * NOTE: When reverse computing the baud rate from the "data" all
         * allowed baud rates are within 3% of the initial baud rate.
         */
        data = (UARK_BAUD_REF + (speed / 2)) / speed;

        uark_cfg_write(sc, 3, 0x83);
        uark_cfg_write(sc, 0, data & 0xFF);
        uark_cfg_write(sc, 1, data >> 8);
        uark_cfg_write(sc, 3, 0x03);

        if (t->c_cflag & CSTOPB)
                data = UARK_STOP_BITS_2;
        else
                data = UARK_STOP_BITS_1;

        if (t->c_cflag & PARENB) {
                if (t->c_cflag & PARODD)
                        data |= UARK_PARITY_ODD;
                else
                        data |= UARK_PARITY_EVEN;
        } else
                data |= UARK_PARITY_NONE;

        switch (t->c_cflag & CSIZE) {
        case CS5:
                data |= UARK_SET_DATA_BITS(5);
                break;
        case CS6:
                data |= UARK_SET_DATA_BITS(6);
                break;
        case CS7:
                data |= UARK_SET_DATA_BITS(7);
                break;
        default:
        case CS8:
                data |= UARK_SET_DATA_BITS(8);
                break;
        }
        uark_cfg_write(sc, 3, 0x00);
        uark_cfg_write(sc, 3, data);
}

static void
uark_cfg_get_status(struct ucom_softc *ucom, uint8_t *lsr, uint8_t *msr)
{
        struct uark_softc *sc = ucom->sc_parent;

        /* XXX Note: sc_lsr is always zero */
        *lsr = sc->sc_lsr;
        *msr = sc->sc_msr;
}

static void
uark_cfg_set_break(struct ucom_softc *ucom, uint8_t onoff)
{
        struct uark_softc *sc = ucom->sc_parent;

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

        uark_cfg_write(sc, 4, onoff ? 0x01 : 0x00);
}

static void
uark_cfg_write(struct uark_softc *sc, uint16_t index, uint16_t value)
{
        struct usb_device_request req;
        usb_error_t err;

        req.bmRequestType = UARK_WRITE;
        req.bRequest = UARK_REQUEST;
        USETW(req.wValue, value);
        USETW(req.wIndex, index);
        USETW(req.wLength, 0);

        err = ucom_cfg_do_request(sc->sc_udev, &sc->sc_ucom, 
            &req, NULL, 0, 1000);
        if (err) {
                DPRINTFN(0, "device request failed, err=%s "
                    "(ignored)\n", usbd_errstr(err));
        }
}

static void
uark_poll(struct ucom_softc *ucom)
{
        struct uark_softc *sc = ucom->sc_parent;
        usbd_transfer_poll(sc->sc_xfer, UARK_N_TRANSFER);
}