/*
 * Infinity Unlimited USB Phoenix driver
 *
 * Copyright (C) 2010 James Courtier-Dutton (James@superbug.co.uk)

 * Copyright (C) 2007 Alain Degreffe (eczema@ecze.com)
 *
 * Original code taken from iuutool (Copyright (C) 2006 Juan Carlos Borr\xC3\x83\xC2\xA1s)
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *
 *  And tested with help of WB Electronics
 *
 */
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "iuu_phoenix.h"
#include <linux/random.h>

#define DRIVER_DESC "Infinity USB Unlimited Phoenix driver"

static const struct usb_device_id id_table[] = {
        {USB_DEVICE(IUU_USB_VENDOR_ID, IUU_USB_PRODUCT_ID)},
        {}                      /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, id_table);

/* turbo parameter */
static int boost = 100;
static int clockmode = 1;
static int cdmode = 1;
static int iuu_cardin;
static int iuu_cardout;
static bool xmas;
static int vcc_default = 5;

static int iuu_create_sysfs_attrs(struct usb_serial_port *port);
static int iuu_remove_sysfs_attrs(struct usb_serial_port *port);
static void read_rxcmd_callback(struct urb *urb);

struct iuu_private {
        spinlock_t lock;        /* store irq state */
        wait_queue_head_t delta_msr_wait;
        u8 line_status;
        int tiostatus;          /* store IUART SIGNAL for tiocmget call */
        u8 reset;               /* if 1 reset is needed */
        int poll;               /* number of poll */
        u8 *writebuf;           /* buffer for writing to device */
        int writelen;           /* num of byte to write to device */
        u8 *buf;                /* used for initialize speed */
        u8 len;
        int vcc;                /* vcc (either 3 or 5 V) */
        u32 baud;
        u32 boost;
        u32 clk;
};

static int iuu_port_probe(struct usb_serial_port *port)
{
        struct iuu_private *priv;
        int ret;

        priv = kzalloc(sizeof(struct iuu_private), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;

        priv->buf = kzalloc(256, GFP_KERNEL);
        if (!priv->buf) {
                kfree(priv);
                return -ENOMEM;
        }

        priv->writebuf = kzalloc(256, GFP_KERNEL);
        if (!priv->writebuf) {
                kfree(priv->buf);
                kfree(priv);
                return -ENOMEM;
        }

        priv->vcc = vcc_default;
        spin_lock_init(&priv->lock);
        init_waitqueue_head(&priv->delta_msr_wait);

        usb_set_serial_port_data(port, priv);

        ret = iuu_create_sysfs_attrs(port);
        if (ret) {
                kfree(priv->writebuf);
                kfree(priv->buf);
                kfree(priv);
                return ret;
        }

        return 0;
}

static int iuu_port_remove(struct usb_serial_port *port)
{
        struct iuu_private *priv = usb_get_serial_port_data(port);

        iuu_remove_sysfs_attrs(port);
        kfree(priv->writebuf);
        kfree(priv->buf);
        kfree(priv);

        return 0;
}

static int iuu_tiocmset(struct tty_struct *tty,
                        unsigned int set, unsigned int clear)
{
        struct usb_serial_port *port = tty->driver_data;
        struct iuu_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;

        /* FIXME: locking on tiomstatus */
        dev_dbg(&port->dev, "%s msg : SET = 0x%04x, CLEAR = 0x%04x\n",
                __func__, set, clear);

        spin_lock_irqsave(&priv->lock, flags);

        if ((set & TIOCM_RTS) && !(priv->tiostatus == TIOCM_RTS)) {
                dev_dbg(&port->dev, "%s TIOCMSET RESET called !!!\n", __func__);
                priv->reset = 1;
        }
        if (set & TIOCM_RTS)
                priv->tiostatus = TIOCM_RTS;

        spin_unlock_irqrestore(&priv->lock, flags);
        return 0;
}

/* This is used to provide a carrier detect mechanism
 * When a card is present, the response is 0x00
 * When no card , the reader respond with TIOCM_CD
 * This is known as CD autodetect mechanism
 */
static int iuu_tiocmget(struct tty_struct *tty)
{
        struct usb_serial_port *port = tty->driver_data;
        struct iuu_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
        int rc;

        spin_lock_irqsave(&priv->lock, flags);
        rc = priv->tiostatus;
        spin_unlock_irqrestore(&priv->lock, flags);

        return rc;
}

static void iuu_rxcmd(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        int result;
        int status = urb->status;

        if (status) {
                dev_dbg(&port->dev, "%s - status = %d\n", __func__, status);
                /* error stop all */
                return;
        }


        memset(port->write_urb->transfer_buffer, IUU_UART_RX, 1);
        usb_fill_bulk_urb(port->write_urb, port->serial->dev,
                          usb_sndbulkpipe(port->serial->dev,
                                          port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer, 1,
                          read_rxcmd_callback, port);
        result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
}

static int iuu_reset(struct usb_serial_port *port, u8 wt)
{
        struct iuu_private *priv = usb_get_serial_port_data(port);
        int result;
        char *buf_ptr = port->write_urb->transfer_buffer;

        /* Prepare the reset sequence */

        *buf_ptr++ = IUU_RST_SET;
        *buf_ptr++ = IUU_DELAY_MS;
        *buf_ptr++ = wt;
        *buf_ptr = IUU_RST_CLEAR;

        /* send the sequence */

        usb_fill_bulk_urb(port->write_urb,
                          port->serial->dev,
                          usb_sndbulkpipe(port->serial->dev,
                                          port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer, 4, iuu_rxcmd, port);
        result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
        priv->reset = 0;
        return result;
}

/* Status Function
 * Return value is
 * 0x00 = no card
 * 0x01 = smartcard
 * 0x02 = sim card
 */
static void iuu_update_status_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        struct iuu_private *priv = usb_get_serial_port_data(port);
        u8 *st;
        int status = urb->status;

        if (status) {
                dev_dbg(&port->dev, "%s - status = %d\n", __func__, status);
                /* error stop all */
                return;
        }

        st = urb->transfer_buffer;
        dev_dbg(&port->dev, "%s - enter\n", __func__);
        if (urb->actual_length == 1) {
                switch (st[0]) {
                case 0x1:
                        priv->tiostatus = iuu_cardout;
                        break;
                case 0x0:
                        priv->tiostatus = iuu_cardin;
                        break;
                default:
                        priv->tiostatus = iuu_cardin;
                }
        }
        iuu_rxcmd(urb);
}

static void iuu_status_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        int result;
        int status = urb->status;

        dev_dbg(&port->dev, "%s - status = %d\n", __func__, status);
        usb_fill_bulk_urb(port->read_urb, port->serial->dev,
                          usb_rcvbulkpipe(port->serial->dev,
                                          port->bulk_in_endpointAddress),
                          port->read_urb->transfer_buffer, 256,
                          iuu_update_status_callback, port);
        result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
}

static int iuu_status(struct usb_serial_port *port)
{
        int result;

        memset(port->write_urb->transfer_buffer, IUU_GET_STATE_REGISTER, 1);
        usb_fill_bulk_urb(port->write_urb, port->serial->dev,
                          usb_sndbulkpipe(port->serial->dev,
                                          port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer, 1,
                          iuu_status_callback, port);
        result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
        return result;

}

static int bulk_immediate(struct usb_serial_port *port, u8 *buf, u8 count)
{
        int status;
        struct usb_serial *serial = port->serial;
        int actual = 0;

        /* send the data out the bulk port */

        status =
            usb_bulk_msg(serial->dev,
                         usb_sndbulkpipe(serial->dev,
                                         port->bulk_out_endpointAddress), buf,
                         count, &actual, 1000);

        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - error = %2x\n", __func__, status);
        else
                dev_dbg(&port->dev, "%s - write OK !\n", __func__);
        return status;
}

static int read_immediate(struct usb_serial_port *port, u8 *buf, u8 count)
{
        int status;
        struct usb_serial *serial = port->serial;
        int actual = 0;

        /* send the data out the bulk port */
        status =
            usb_bulk_msg(serial->dev,
                         usb_rcvbulkpipe(serial->dev,
                                         port->bulk_in_endpointAddress), buf,
                         count, &actual, 1000);

        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - error = %2x\n", __func__, status);
        else
                dev_dbg(&port->dev, "%s - read OK !\n", __func__);
        return status;
}

static int iuu_led(struct usb_serial_port *port, unsigned int R,
                   unsigned int G, unsigned int B, u8 f)
{
        int status;
        u8 *buf;
        buf = kmalloc(8, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        buf[0] = IUU_SET_LED;
        buf[1] = R & 0xFF;
        buf[2] = (R >> 8) & 0xFF;
        buf[3] = G & 0xFF;
        buf[4] = (G >> 8) & 0xFF;
        buf[5] = B & 0xFF;
        buf[6] = (B >> 8) & 0xFF;
        buf[7] = f;
        status = bulk_immediate(port, buf, 8);
        kfree(buf);
        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - led error status = %2x\n", __func__, status);
        else
                dev_dbg(&port->dev, "%s - led OK !\n", __func__);
        return IUU_OPERATION_OK;
}

static void iuu_rgbf_fill_buffer(u8 *buf, u8 r1, u8 r2, u8 g1, u8 g2, u8 b1,
                                 u8 b2, u8 freq)
{
        *buf++ = IUU_SET_LED;
        *buf++ = r1;
        *buf++ = r2;
        *buf++ = g1;
        *buf++ = g2;
        *buf++ = b1;
        *buf++ = b2;
        *buf = freq;
}

static void iuu_led_activity_on(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        int result;
        char *buf_ptr = port->write_urb->transfer_buffer;
        *buf_ptr++ = IUU_SET_LED;
        if (xmas == 1) {
                get_random_bytes(buf_ptr, 6);
                *(buf_ptr+7) = 1;
        } else {
                iuu_rgbf_fill_buffer(buf_ptr, 255, 255, 0, 0, 0, 0, 255);
        }

        usb_fill_bulk_urb(port->write_urb, port->serial->dev,
                          usb_sndbulkpipe(port->serial->dev,
                                          port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer, 8 ,
                          iuu_rxcmd, port);
        result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
}

static void iuu_led_activity_off(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        int result;
        char *buf_ptr = port->write_urb->transfer_buffer;
        if (xmas == 1) {
                iuu_rxcmd(urb);
                return;
        } else {
                *buf_ptr++ = IUU_SET_LED;
                iuu_rgbf_fill_buffer(buf_ptr, 0, 0, 255, 255, 0, 0, 255);
        }
        usb_fill_bulk_urb(port->write_urb, port->serial->dev,
                          usb_sndbulkpipe(port->serial->dev,
                                          port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer, 8 ,
                          iuu_rxcmd, port);
        result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
}



static int iuu_clk(struct usb_serial_port *port, int dwFrq)
{
        int status;
        struct iuu_private *priv = usb_get_serial_port_data(port);
        int Count = 0;
        u8 FrqGenAdr = 0x69;
        u8 DIV = 0;             /* 8bit */
        u8 XDRV = 0;            /* 8bit */
        u8 PUMP = 0;            /* 3bit */
        u8 PBmsb = 0;           /* 2bit */
        u8 PBlsb = 0;           /* 8bit */
        u8 PO = 0;              /* 1bit */
        u8 Q = 0;               /* 7bit */
        /* 24bit = 3bytes */
        unsigned int P = 0;
        unsigned int P2 = 0;
        int frq = (int)dwFrq;

        if (frq == 0) {
                priv->buf[Count++] = IUU_UART_WRITE_I2C;
                priv->buf[Count++] = FrqGenAdr << 1;
                priv->buf[Count++] = 0x09;
                priv->buf[Count++] = 0x00;

                status = bulk_immediate(port, (u8 *) priv->buf, Count);
                if (status != 0) {
                        dev_dbg(&port->dev, "%s - write error\n", __func__);
                        return status;
                }
        } else if (frq == 3579000) {
                DIV = 100;
                P = 1193;
                Q = 40;
                XDRV = 0;
        } else if (frq == 3680000) {
                DIV = 105;
                P = 161;
                Q = 5;
                XDRV = 0;
        } else if (frq == 6000000) {
                DIV = 66;
                P = 66;
                Q = 2;
                XDRV = 0x28;
        } else {
                unsigned int result = 0;
                unsigned int tmp = 0;
                unsigned int check;
                unsigned int check2;
                char found = 0x00;
                unsigned int lQ = 2;
                unsigned int lP = 2055;
                unsigned int lDiv = 4;

                for (lQ = 2; lQ <= 47 && !found; lQ++)
                        for (lP = 2055; lP >= 8 && !found; lP--)
                                for (lDiv = 4; lDiv <= 127 && !found; lDiv++) {
                                        tmp = (12000000 / lDiv) * (lP / lQ);
                                        if (abs((int)(tmp - frq)) <
                                            abs((int)(frq - result))) {
                                                check2 = (12000000 / lQ);
                                                if (check2 < 250000)
                                                        continue;
                                                check = (12000000 / lQ) * lP;
                                                if (check > 400000000)
                                                        continue;
                                                if (check < 100000000)
                                                        continue;
                                                if (lDiv < 4 || lDiv > 127)
                                                        continue;
                                                result = tmp;
                                                P = lP;
                                                DIV = lDiv;
                                                Q = lQ;
                                                if (result == frq)
                                                        found = 0x01;
                                        }
                                }
        }
        P2 = ((P - PO) / 2) - 4;
        DIV = DIV;
        PUMP = 0x04;
        PBmsb = (P2 >> 8 & 0x03);
        PBlsb = P2 & 0xFF;
        PO = (P >> 10) & 0x01;
        Q = Q - 2;

        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /* 0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x09;
        priv->buf[Count++] = 0x20;      /* Adr = 0x09 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /* 0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x0C;
        priv->buf[Count++] = DIV;       /* Adr = 0x0C */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /* 0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x12;
        priv->buf[Count++] = XDRV;      /* Adr = 0x12 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x13;
        priv->buf[Count++] = 0x6B;      /* Adr = 0x13 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x40;
        priv->buf[Count++] = (0xC0 | ((PUMP & 0x07) << 2)) |
                             (PBmsb & 0x03);    /* Adr = 0x40 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x41;
        priv->buf[Count++] = PBlsb;     /* Adr = 0x41 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x42;
        priv->buf[Count++] = Q | (((PO & 0x01) << 7));  /* Adr = 0x42 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x44;
        priv->buf[Count++] = (char)0xFF;        /* Adr = 0x44 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x45;
        priv->buf[Count++] = (char)0xFE;        /* Adr = 0x45 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x46;
        priv->buf[Count++] = 0x7F;      /* Adr = 0x46 */
        priv->buf[Count++] = IUU_UART_WRITE_I2C;        /*  0x4C */
        priv->buf[Count++] = FrqGenAdr << 1;
        priv->buf[Count++] = 0x47;
        priv->buf[Count++] = (char)0x84;        /* Adr = 0x47 */

        status = bulk_immediate(port, (u8 *) priv->buf, Count);
        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - write error\n", __func__);
        return status;
}

static int iuu_uart_flush(struct usb_serial_port *port)
{
        struct device *dev = &port->dev;
        int i;
        int status;
        u8 rxcmd = IUU_UART_RX;
        struct iuu_private *priv = usb_get_serial_port_data(port);

        if (iuu_led(port, 0xF000, 0, 0, 0xFF) < 0)
                return -EIO;

        for (i = 0; i < 2; i++) {
                status = bulk_immediate(port, &rxcmd, 1);
                if (status != IUU_OPERATION_OK) {
                        dev_dbg(dev, "%s - uart_flush_write error\n", __func__);
                        return status;
                }

                status = read_immediate(port, &priv->len, 1);
                if (status != IUU_OPERATION_OK) {
                        dev_dbg(dev, "%s - uart_flush_read error\n", __func__);
                        return status;
                }

                if (priv->len > 0) {
                        dev_dbg(dev, "%s - uart_flush datalen is : %i\n", __func__, priv->len);
                        status = read_immediate(port, priv->buf, priv->len);
                        if (status != IUU_OPERATION_OK) {
                                dev_dbg(dev, "%s - uart_flush_read error\n", __func__);
                                return status;
                        }
                }
        }
        dev_dbg(dev, "%s - uart_flush_read OK!\n", __func__);
        iuu_led(port, 0, 0xF000, 0, 0xFF);
        return status;
}

static void read_buf_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        unsigned char *data = urb->transfer_buffer;
        int status = urb->status;

        if (status) {
                if (status == -EPROTO) {
                        /* reschedule needed */
                }
                return;
        }

        dev_dbg(&port->dev, "%s - %i chars to write\n", __func__, urb->actual_length);
        if (data == NULL)
                dev_dbg(&port->dev, "%s - data is NULL !!!\n", __func__);
        if (urb->actual_length && data) {
                tty_insert_flip_string(&port->port, data, urb->actual_length);
                tty_flip_buffer_push(&port->port);
        }
        iuu_led_activity_on(urb);
}

static int iuu_bulk_write(struct usb_serial_port *port)
{
        struct iuu_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
        int result;
        int buf_len;
        char *buf_ptr = port->write_urb->transfer_buffer;

        spin_lock_irqsave(&priv->lock, flags);
        *buf_ptr++ = IUU_UART_ESC;
        *buf_ptr++ = IUU_UART_TX;
        *buf_ptr++ = priv->writelen;

        memcpy(buf_ptr, priv->writebuf, priv->writelen);
        buf_len = priv->writelen;
        priv->writelen = 0;
        spin_unlock_irqrestore(&priv->lock, flags);
        dev_dbg(&port->dev, "%s - writing %i chars : %*ph\n", __func__,
                buf_len, buf_len, buf_ptr);
        usb_fill_bulk_urb(port->write_urb, port->serial->dev,
                          usb_sndbulkpipe(port->serial->dev,
                                          port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer, buf_len + 3,
                          iuu_rxcmd, port);
        result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
        usb_serial_port_softint(port);
        return result;
}

static int iuu_read_buf(struct usb_serial_port *port, int len)
{
        int result;

        usb_fill_bulk_urb(port->read_urb, port->serial->dev,
                          usb_rcvbulkpipe(port->serial->dev,
                                          port->bulk_in_endpointAddress),
                          port->read_urb->transfer_buffer, len,
                          read_buf_callback, port);
        result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
        return result;
}

static void iuu_uart_read_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        struct iuu_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
        int status = urb->status;
        int error = 0;
        int len = 0;
        unsigned char *data = urb->transfer_buffer;
        priv->poll++;

        if (status) {
                dev_dbg(&port->dev, "%s - status = %d\n", __func__, status);
                /* error stop all */
                return;
        }
        if (data == NULL)
                dev_dbg(&port->dev, "%s - data is NULL !!!\n", __func__);

        if (urb->actual_length == 1  && data != NULL)
                len = (int) data[0];

        if (urb->actual_length > 1) {
                dev_dbg(&port->dev, "%s - urb->actual_length = %i\n", __func__,
                    urb->actual_length);
                error = 1;
                return;
        }
        /* if len > 0 call readbuf */

        if (len > 0 && error == 0) {
                dev_dbg(&port->dev, "%s - call read buf - len to read is %i\n",
                        __func__, len);
                status = iuu_read_buf(port, len);
                return;
        }
        /* need to update status  ? */
        if (priv->poll > 99) {
                status = iuu_status(port);
                priv->poll = 0;
                return;
        }

        /* reset waiting ? */

        if (priv->reset == 1) {
                status = iuu_reset(port, 0xC);
                return;
        }
        /* Writebuf is waiting */
        spin_lock_irqsave(&priv->lock, flags);
        if (priv->writelen > 0) {
                spin_unlock_irqrestore(&priv->lock, flags);
                status = iuu_bulk_write(port);
                return;
        }
        spin_unlock_irqrestore(&priv->lock, flags);
        /* if nothing to write call again rxcmd */
        dev_dbg(&port->dev, "%s - rxcmd recall\n", __func__);
        iuu_led_activity_off(urb);
}

static int iuu_uart_write(struct tty_struct *tty, struct usb_serial_port *port,
                          const u8 *buf, int count)
{
        struct iuu_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;

        if (count > 256)
                return -ENOMEM;

        spin_lock_irqsave(&priv->lock, flags);

        /* fill the buffer */
        memcpy(priv->writebuf + priv->writelen, buf, count);
        priv->writelen += count;
        spin_unlock_irqrestore(&priv->lock, flags);

        return count;
}

static void read_rxcmd_callback(struct urb *urb)
{
        struct usb_serial_port *port = urb->context;
        int result;
        int status = urb->status;

        if (status) {
                /* error stop all */
                return;
        }

        usb_fill_bulk_urb(port->read_urb, port->serial->dev,
                          usb_rcvbulkpipe(port->serial->dev,
                                          port->bulk_in_endpointAddress),
                          port->read_urb->transfer_buffer, 256,
                          iuu_uart_read_callback, port);
        result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
        dev_dbg(&port->dev, "%s - submit result = %d\n", __func__, result);
}

static int iuu_uart_on(struct usb_serial_port *port)
{
        int status;
        u8 *buf;

        buf = kmalloc(sizeof(u8) * 4, GFP_KERNEL);

        if (!buf)
                return -ENOMEM;

        buf[0] = IUU_UART_ENABLE;
        buf[1] = (u8) ((IUU_BAUD_9600 >> 8) & 0x00FF);
        buf[2] = (u8) (0x00FF & IUU_BAUD_9600);
        buf[3] = (u8) (0x0F0 & IUU_ONE_STOP_BIT) | (0x07 & IUU_PARITY_EVEN);

        status = bulk_immediate(port, buf, 4);
        if (status != IUU_OPERATION_OK) {
                dev_dbg(&port->dev, "%s - uart_on error\n", __func__);
                goto uart_enable_failed;
        }
        /*  iuu_reset() the card after iuu_uart_on() */
        status = iuu_uart_flush(port);
        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - uart_flush error\n", __func__);
uart_enable_failed:
        kfree(buf);
        return status;
}

/*  Diables the IUU UART (a.k.a. the Phoenix voiderface) */
static int iuu_uart_off(struct usb_serial_port *port)
{
        int status;
        u8 *buf;
        buf = kmalloc(1, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;
        buf[0] = IUU_UART_DISABLE;

        status = bulk_immediate(port, buf, 1);
        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - uart_off error\n", __func__);

        kfree(buf);
        return status;
}

static int iuu_uart_baud(struct usb_serial_port *port, u32 baud_base,
                         u32 *actual, u8 parity)
{
        int status;
        u32 baud;
        u8 *dataout;
        u8 DataCount = 0;
        u8 T1Frekvens = 0;
        u8 T1reload = 0;
        unsigned int T1FrekvensHZ = 0;

        dev_dbg(&port->dev, "%s - enter baud_base=%d\n", __func__, baud_base);
        dataout = kmalloc(sizeof(u8) * 5, GFP_KERNEL);

        if (!dataout)
                return -ENOMEM;
        /*baud = (((priv->clk / 35) * baud_base) / 100000); */
        baud = baud_base;

        if (baud < 1200 || baud > 230400) {
                kfree(dataout);
                return IUU_INVALID_PARAMETER;
        }
        if (baud > 977) {
                T1Frekvens = 3;
                T1FrekvensHZ = 500000;
        }

        if (baud > 3906) {
                T1Frekvens = 2;
                T1FrekvensHZ = 2000000;
        }

        if (baud > 11718) {
                T1Frekvens = 1;
                T1FrekvensHZ = 6000000;
        }

        if (baud > 46875) {
                T1Frekvens = 0;
                T1FrekvensHZ = 24000000;
        }

        T1reload = 256 - (u8) (T1FrekvensHZ / (baud * 2));

        /*  magic number here:  ENTER_FIRMWARE_UPDATE; */
        dataout[DataCount++] = IUU_UART_ESC;
        /*  magic number here:  CHANGE_BAUD; */
        dataout[DataCount++] = IUU_UART_CHANGE;
        dataout[DataCount++] = T1Frekvens;
        dataout[DataCount++] = T1reload;

        *actual = (T1FrekvensHZ / (256 - T1reload)) / 2;

        switch (parity & 0x0F) {
        case IUU_PARITY_NONE:
                dataout[DataCount++] = 0x00;
                break;
        case IUU_PARITY_EVEN:
                dataout[DataCount++] = 0x01;
                break;
        case IUU_PARITY_ODD:
                dataout[DataCount++] = 0x02;
                break;
        case IUU_PARITY_MARK:
                dataout[DataCount++] = 0x03;
                break;
        case IUU_PARITY_SPACE:
                dataout[DataCount++] = 0x04;
                break;
        default:
                kfree(dataout);
                return IUU_INVALID_PARAMETER;
                break;
        }

        switch (parity & 0xF0) {
        case IUU_ONE_STOP_BIT:
                dataout[DataCount - 1] |= IUU_ONE_STOP_BIT;
                break;

        case IUU_TWO_STOP_BITS:
                dataout[DataCount - 1] |= IUU_TWO_STOP_BITS;
                break;
        default:
                kfree(dataout);
                return IUU_INVALID_PARAMETER;
                break;
        }

        status = bulk_immediate(port, dataout, DataCount);
        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - uart_off error\n", __func__);
        kfree(dataout);
        return status;
}

static void iuu_set_termios(struct tty_struct *tty,
                struct usb_serial_port *port, struct ktermios *old_termios)
{
        const u32 supported_mask = CMSPAR|PARENB|PARODD;
        struct iuu_private *priv = usb_get_serial_port_data(port);
        unsigned int cflag = tty->termios.c_cflag;
        int status;
        u32 actual;
        u32 parity;
        int csize = CS7;
        int baud;
        u32 newval = cflag & supported_mask;

        /* Just use the ospeed. ispeed should be the same. */
        baud = tty->termios.c_ospeed;

        dev_dbg(&port->dev, "%s - enter c_ospeed or baud=%d\n", __func__, baud);

        /* compute the parity parameter */
        parity = 0;
        if (cflag & CMSPAR) {   /* Using mark space */
                if (cflag & PARODD)
                        parity |= IUU_PARITY_SPACE;
                else
                        parity |= IUU_PARITY_MARK;
        } else if (!(cflag & PARENB)) {
                parity |= IUU_PARITY_NONE;
                csize = CS8;
        } else if (cflag & PARODD)
                parity |= IUU_PARITY_ODD;
        else
                parity |= IUU_PARITY_EVEN;

        parity |= (cflag & CSTOPB ? IUU_TWO_STOP_BITS : IUU_ONE_STOP_BIT);

        /* set it */
        status = iuu_uart_baud(port,
                        baud * priv->boost / 100,
                        &actual, parity);

        /* set the termios value to the real one, so the user now what has
         * changed. We support few fields so its easies to copy the old hw
         * settings back over and then adjust them
         */
        if (old_termios)
                tty_termios_copy_hw(&tty->termios, old_termios);
        if (status != 0)        /* Set failed - return old bits */
                return;
        /* Re-encode speed, parity and csize */
        tty_encode_baud_rate(tty, baud, baud);
        tty->termios.c_cflag &= ~(supported_mask|CSIZE);
        tty->termios.c_cflag |= newval | csize;
}

static void iuu_close(struct usb_serial_port *port)
{
        /* iuu_led (port,255,0,0,0); */
        struct usb_serial *serial;

        serial = port->serial;
        if (!serial)
                return;

        iuu_uart_off(port);
        if (serial->dev) {
                /* free writebuf */
                /* shutdown our urbs */
                dev_dbg(&port->dev, "%s - shutting down urbs\n", __func__);
                usb_kill_urb(port->write_urb);
                usb_kill_urb(port->read_urb);
                usb_kill_urb(port->interrupt_in_urb);
                iuu_led(port, 0, 0, 0xF000, 0xFF);
        }
}

static void iuu_init_termios(struct tty_struct *tty)
{
        tty->termios = tty_std_termios;
        tty->termios.c_cflag = CLOCAL | CREAD | CS8 | B9600
                                | TIOCM_CTS | CSTOPB | PARENB;
        tty->termios.c_ispeed = 9600;
        tty->termios.c_ospeed = 9600;
        tty->termios.c_lflag = 0;
        tty->termios.c_oflag = 0;
        tty->termios.c_iflag = 0;
}

static int iuu_open(struct tty_struct *tty, struct usb_serial_port *port)
{
        struct usb_serial *serial = port->serial;
        struct device *dev = &port->dev;
        u8 *buf;
        int result;
        int baud;
        u32 actual;
        struct iuu_private *priv = usb_get_serial_port_data(port);

        baud = tty->termios.c_ospeed;
        tty->termios.c_ispeed = baud;
        /* Re-encode speed */
        tty_encode_baud_rate(tty, baud, baud);

        dev_dbg(dev, "%s - baud %d\n", __func__, baud);
        usb_clear_halt(serial->dev, port->write_urb->pipe);
        usb_clear_halt(serial->dev, port->read_urb->pipe);

        buf = kmalloc(10, GFP_KERNEL);
        if (buf == NULL)
                return -ENOMEM;

        priv->poll = 0;

        /* initialize writebuf */
#define FISH(a, b, c, d) do { \
        result = usb_control_msg(port->serial->dev,     \
                                usb_rcvctrlpipe(port->serial->dev, 0),  \
                                b, a, c, d, buf, 1, 1000); \
        dev_dbg(dev, "0x%x:0x%x:0x%x:0x%x  %d - %x\n", a, b, c, d, result, \
                                buf[0]); } while (0);

#define SOUP(a, b, c, d)  do { \
        result = usb_control_msg(port->serial->dev,     \
                                usb_sndctrlpipe(port->serial->dev, 0),  \
                                b, a, c, d, NULL, 0, 1000); \
        dev_dbg(dev, "0x%x:0x%x:0x%x:0x%x  %d\n", a, b, c, d, result); } while (0)

        /*  This is not UART related but IUU USB driver related or something */
        /*  like that. Basically no IUU will accept any commands from the USB */
        /*  host unless it has received the following message */
        /* sprintf(buf ,"%c%c%c%c",0x03,0x02,0x02,0x0); */

        SOUP(0x03, 0x02, 0x02, 0x0);
        kfree(buf);
        iuu_led(port, 0xF000, 0xF000, 0, 0xFF);
        iuu_uart_on(port);
        if (boost < 100)
                boost = 100;
        priv->boost = boost;
        priv->baud = baud;
        switch (clockmode) {
        case 2:         /*  3.680 Mhz */
                priv->clk = IUU_CLK_3680000;
                iuu_clk(port, IUU_CLK_3680000 * boost / 100);
                result =
                    iuu_uart_baud(port, baud * boost / 100, &actual,
                                  IUU_PARITY_EVEN);
                break;
        case 3:         /*  6.00 Mhz */
                iuu_clk(port, IUU_CLK_6000000 * boost / 100);
                priv->clk = IUU_CLK_6000000;
                /* Ratio of 6000000 to 3500000 for baud 9600 */
                result =
                    iuu_uart_baud(port, 16457 * boost / 100, &actual,
                                  IUU_PARITY_EVEN);
                break;
        default:                /*  3.579 Mhz */
                iuu_clk(port, IUU_CLK_3579000 * boost / 100);
                priv->clk = IUU_CLK_3579000;
                result =
                    iuu_uart_baud(port, baud * boost / 100, &actual,
                                  IUU_PARITY_EVEN);
        }

        /* set the cardin cardout signals */
        switch (cdmode) {
        case 0:
                iuu_cardin = 0;
                iuu_cardout = 0;
                break;
        case 1:
                iuu_cardin = TIOCM_CD;
                iuu_cardout =  0;
                break;
        case 2:
                iuu_cardin = 0;
                iuu_cardout = TIOCM_CD;
                break;
        case 3:
                iuu_cardin = TIOCM_DSR;
                iuu_cardout = 0;
                break;
        case 4:
                iuu_cardin = 0;
                iuu_cardout = TIOCM_DSR;
                break;
        case 5:
                iuu_cardin = TIOCM_CTS;
                iuu_cardout = 0;
                break;
        case 6:
                iuu_cardin = 0;
                iuu_cardout = TIOCM_CTS;
                break;
        case 7:
                iuu_cardin = TIOCM_RNG;
                iuu_cardout = 0;
                break;
        case 8:
                iuu_cardin = 0;
                iuu_cardout = TIOCM_RNG;
        }

        iuu_uart_flush(port);

        dev_dbg(dev, "%s - initialization done\n", __func__);

        memset(port->write_urb->transfer_buffer, IUU_UART_RX, 1);
        usb_fill_bulk_urb(port->write_urb, port->serial->dev,
                          usb_sndbulkpipe(port->serial->dev,
                                          port->bulk_out_endpointAddress),
                          port->write_urb->transfer_buffer, 1,
                          read_rxcmd_callback, port);
        result = usb_submit_urb(port->write_urb, GFP_KERNEL);
        if (result) {
                dev_err(dev, "%s - failed submitting read urb, error %d\n", __func__, result);
                iuu_close(port);
        } else {
                dev_dbg(dev, "%s - rxcmd OK\n", __func__);
        }

        return result;
}

/* how to change VCC */
static int iuu_vcc_set(struct usb_serial_port *port, unsigned int vcc)
{
        int status;
        u8 *buf;

        buf = kmalloc(5, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        buf[0] = IUU_SET_VCC;
        buf[1] = vcc & 0xFF;
        buf[2] = (vcc >> 8) & 0xFF;
        buf[3] = (vcc >> 16) & 0xFF;
        buf[4] = (vcc >> 24) & 0xFF;

        status = bulk_immediate(port, buf, 5);
        kfree(buf);

        if (status != IUU_OPERATION_OK)
                dev_dbg(&port->dev, "%s - vcc error status = %2x\n", __func__, status);
        else
                dev_dbg(&port->dev, "%s - vcc OK !\n", __func__);

        return status;
}

/*
 * Sysfs Attributes
 */

static ssize_t show_vcc_mode(struct device *dev,
        struct device_attribute *attr, char *buf)
{
        struct usb_serial_port *port = to_usb_serial_port(dev);
        struct iuu_private *priv = usb_get_serial_port_data(port);

        return sprintf(buf, "%d\n", priv->vcc);
}

static ssize_t store_vcc_mode(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t count)
{
        struct usb_serial_port *port = to_usb_serial_port(dev);
        struct iuu_private *priv = usb_get_serial_port_data(port);
        unsigned long v;

        if (kstrtoul(buf, 10, &v)) {
                dev_err(dev, "%s - vcc_mode: %s is not a unsigned long\n",
                                __func__, buf);
                goto fail_store_vcc_mode;
        }

        dev_dbg(dev, "%s: setting vcc_mode = %ld", __func__, v);

        if ((v != 3) && (v != 5)) {
                dev_err(dev, "%s - vcc_mode %ld is invalid\n", __func__, v);
        } else {
                iuu_vcc_set(port, v);
                priv->vcc = v;
        }
fail_store_vcc_mode:
        return count;
}

static DEVICE_ATTR(vcc_mode, S_IRUSR | S_IWUSR, show_vcc_mode,
        store_vcc_mode);

static int iuu_create_sysfs_attrs(struct usb_serial_port *port)
{
        return device_create_file(&port->dev, &dev_attr_vcc_mode);
}

static int iuu_remove_sysfs_attrs(struct usb_serial_port *port)
{
        device_remove_file(&port->dev, &dev_attr_vcc_mode);
        return 0;
}

/*
 * End Sysfs Attributes
 */

static struct usb_serial_driver iuu_device = {
        .driver = {
                   .owner = THIS_MODULE,
                   .name = "iuu_phoenix",
                   },
        .id_table = id_table,
        .num_ports = 1,
        .bulk_in_size = 512,
        .bulk_out_size = 512,
        .open = iuu_open,
        .close = iuu_close,
        .write = iuu_uart_write,
        .read_bulk_callback = iuu_uart_read_callback,
        .tiocmget = iuu_tiocmget,
        .tiocmset = iuu_tiocmset,
        .set_termios = iuu_set_termios,
        .init_termios = iuu_init_termios,
        .port_probe = iuu_port_probe,
        .port_remove = iuu_port_remove,
};

static struct usb_serial_driver * const serial_drivers[] = {
        &iuu_device, NULL
};

module_usb_serial_driver(serial_drivers, id_table);

MODULE_AUTHOR("Alain Degreffe eczema@ecze.com");

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

module_param(xmas, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(xmas, "Xmas colors enabled or not");

module_param(boost, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(boost, "Card overclock boost (in percent 100-500)");

module_param(clockmode, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(clockmode, "Card clock mode (1=3.579 MHz, 2=3.680 MHz, "
                "3=6 Mhz)");

module_param(cdmode, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(cdmode, "Card detect mode (0=none, 1=CD, 2=!CD, 3=DSR, "
                 "4=!DSR, 5=CTS, 6=!CTS, 7=RING, 8=!RING)");

module_param(vcc_default, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(vcc_default, "Set default VCC (either 3 for 3.3V or 5 "
                "for 5V). Default to 5.");