Linux-2.6.12-rc2

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / usb / serial / kl5kusb105.c

/*
 * KLSI KL5KUSB105 chip RS232 converter driver
 *
 *   Copyright (C) 2001 Utz-Uwe Haus <haus@uuhaus.de>
 *
 *   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.
 *
 * All information about the device was acquired using SniffUSB ans snoopUSB
 * on Windows98.
 * It was written out of frustration with the PalmConnect USB Serial adapter
 * sold by Palm Inc.
 * Neither Palm, nor their contractor (MCCI) or their supplier (KLSI) provided
 * information that was not already available.
 *
 * It seems that KLSI bought some silicon-design information from ScanLogic, 
 * whose SL11R processor is at the core of the KL5KUSB chipset from KLSI.
 * KLSI has firmware available for their devices; it is probable that the
 * firmware differs from that used by KLSI in their products. If you have an
 * original KLSI device and can provide some information on it, I would be 
 * most interested in adding support for it here. If you have any information 
 * on the protocol used (or find errors in my reverse-engineered stuff), please
 * let me know.
 *
 * The code was only tested with a PalmConnect USB adapter; if you
 * are adventurous, try it with any KLSI-based device and let me know how it
 * breaks so that I can fix it!
 */

/* TODO:
 *      check modem line signals
 *      implement handshaking or decide that we do not support it
 */

/* History:
 *   0.3a - implemented pools of write URBs
 *   0.3  - alpha version for public testing
 *   0.2  - TIOCMGET works, so autopilot(1) can be used!
 *   0.1  - can be used to to pilot-xfer -p /dev/ttyUSB0 -l
 *
 *   The driver skeleton is mainly based on mct_u232.c and various other 
 *   pieces of code shamelessly copied from the drivers/usb/serial/ directory.
 */


#include <linux/config.h>
#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/module.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include "usb-serial.h"
#include "kl5kusb105.h"

static int debug;

/*
 * Version Information
 */
#define DRIVER_VERSION "v0.3a"
#define DRIVER_AUTHOR "Utz-Uwe Haus <haus@uuhaus.de>"
#define DRIVER_DESC "KLSI KL5KUSB105 chipset USB->Serial Converter driver"


/*
 * Function prototypes
 */
static int  klsi_105_startup             (struct usb_serial *serial);
static void klsi_105_shutdown            (struct usb_serial *serial);
static int  klsi_105_open                (struct usb_serial_port *port,
                                          struct file *filp);
static void klsi_105_close               (struct usb_serial_port *port,
                                          struct file *filp);
static int  klsi_105_write               (struct usb_serial_port *port,
                                          const unsigned char *buf,
                                          int count);
static void klsi_105_write_bulk_callback (struct urb *urb, struct pt_regs *regs);
static int  klsi_105_chars_in_buffer     (struct usb_serial_port *port);
static int  klsi_105_write_room          (struct usb_serial_port *port);

static void klsi_105_read_bulk_callback  (struct urb *urb, struct pt_regs *regs);
static void klsi_105_set_termios         (struct usb_serial_port *port,
                                          struct termios * old);
static int  klsi_105_ioctl               (struct usb_serial_port *port,
                                          struct file * file,
                                          unsigned int cmd,
                                          unsigned long arg);
static void klsi_105_throttle            (struct usb_serial_port *port);
static void klsi_105_unthrottle          (struct usb_serial_port *port);
/*
static void klsi_105_break_ctl           (struct usb_serial_port *port,
                                          int break_state );
 */
static int  klsi_105_tiocmget            (struct usb_serial_port *port,
                                          struct file *file);
static int  klsi_105_tiocmset            (struct usb_serial_port *port,
                                          struct file *file, unsigned int set,
                                          unsigned int clear);

/*
 * All of the device info needed for the KLSI converters.
 */
static struct usb_device_id id_table [] = {
        { USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
        { USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
        { }             /* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, id_table);

static struct usb_driver kl5kusb105d_driver = {
        .owner =        THIS_MODULE,
        .name =         "kl5kusb105d",
        .probe =        usb_serial_probe,
        .disconnect =   usb_serial_disconnect,
        .id_table =     id_table,
};

static struct usb_serial_device_type kl5kusb105d_device = {
        .owner =             THIS_MODULE,
        .name =              "KL5KUSB105D / PalmConnect",
        .short_name =        "kl5kusb105d",
        .id_table =          id_table,
        .num_interrupt_in =  1,
        .num_bulk_in =       1,
        .num_bulk_out =      1,
        .num_ports =         1,
        .open =              klsi_105_open,
        .close =             klsi_105_close,
        .write =             klsi_105_write,
        .write_bulk_callback = klsi_105_write_bulk_callback,
        .chars_in_buffer =   klsi_105_chars_in_buffer,
        .write_room =        klsi_105_write_room,
        .read_bulk_callback =klsi_105_read_bulk_callback,
        .ioctl =             klsi_105_ioctl,
        .set_termios =       klsi_105_set_termios,
        /*.break_ctl =       klsi_105_break_ctl,*/
        .tiocmget =          klsi_105_tiocmget,
        .tiocmset =          klsi_105_tiocmset,
        .attach =            klsi_105_startup,
        .shutdown =          klsi_105_shutdown,
        .throttle =          klsi_105_throttle,
        .unthrottle =        klsi_105_unthrottle,
};

struct klsi_105_port_settings {
        __u8    pktlen;         /* always 5, it seems */
        __u8    baudrate;
        __u8    databits;
        __u8    unknown1;
        __u8    unknown2;
} __attribute__ ((packed));

/* we implement a pool of NUM_URBS urbs per usb_serial */
#define NUM_URBS                        1
#define URB_TRANSFER_BUFFER_SIZE        64
struct klsi_105_private {
        struct klsi_105_port_settings   cfg;
        struct termios                  termios;
        unsigned long                   line_state; /* modem line settings */
        /* write pool */
        struct urb *                    write_urb_pool[NUM_URBS];
        spinlock_t                      lock;
        unsigned long                   bytes_in;
        unsigned long                   bytes_out;
};


/*
 * Handle vendor specific USB requests
 */


#define KLSI_TIMEOUT     5000 /* default urb timeout */

static int klsi_105_chg_port_settings(struct usb_serial_port *port,
                                      struct klsi_105_port_settings *settings)
{
        int rc;

        rc = usb_control_msg(port->serial->dev,
                             usb_sndctrlpipe(port->serial->dev, 0),
                             KL5KUSB105A_SIO_SET_DATA,
                             USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
                             0, /* value */
                             0, /* index */
                             settings,
                             sizeof(struct klsi_105_port_settings),
                             KLSI_TIMEOUT);
        if (rc < 0)
                err("Change port settings failed (error = %d)", rc);
        info("%s - %d byte block, baudrate %x, databits %d, u1 %d, u2 %d",
            __FUNCTION__,
            settings->pktlen,
            settings->baudrate, settings->databits,
            settings->unknown1, settings->unknown2);
        return rc;
} /* klsi_105_chg_port_settings */

/* translate a 16-bit status value from the device to linux's TIO bits */
static unsigned long klsi_105_status2linestate(const __u16 status)
{
        unsigned long res = 0;

        res =   ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
              | ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
              ;

        return res;
}
/* 
 * Read line control via vendor command and return result through
 * *line_state_p 
 */
/* It seems that the status buffer has always only 2 bytes length */
#define KLSI_STATUSBUF_LEN      2
static int klsi_105_get_line_state(struct usb_serial_port *port,
                                   unsigned long *line_state_p)
{
        int rc;
        __u8 status_buf[KLSI_STATUSBUF_LEN] = { -1,-1};
        __u16 status;

        info("%s - sending SIO Poll request", __FUNCTION__);
        rc = usb_control_msg(port->serial->dev,
                             usb_rcvctrlpipe(port->serial->dev, 0),
                             KL5KUSB105A_SIO_POLL,
                             USB_TYPE_VENDOR | USB_DIR_IN,
                             0, /* value */
                             0, /* index */
                             status_buf, KLSI_STATUSBUF_LEN,
                             10000
                             );
        if (rc < 0)
                err("Reading line status failed (error = %d)", rc);
        else {
                status = status_buf[0] + (status_buf[1]<<8);

                info("%s - read status %x %x", __FUNCTION__,
                     status_buf[0], status_buf[1]);

                *line_state_p = klsi_105_status2linestate(status);
        }

        return rc;
}


/*
 * Driver's tty interface functions
 */

static int klsi_105_startup (struct usb_serial *serial)
{
        struct klsi_105_private *priv;
        int i;

        /* check if we support the product id (see keyspan.c)
         * FIXME
         */

        /* allocate the private data structure */
        for (i=0; i<serial->num_ports; i++) {
                int j;
                priv = kmalloc(sizeof(struct klsi_105_private),
                                                   GFP_KERNEL);
                if (!priv) {
                        dbg("%skmalloc for klsi_105_private failed.", __FUNCTION__);
                        return -ENOMEM;
                }
                /* set initial values for control structures */
                priv->cfg.pktlen    = 5;
                priv->cfg.baudrate  = kl5kusb105a_sio_b9600;
                priv->cfg.databits  = kl5kusb105a_dtb_8;
                priv->cfg.unknown1  = 0;
                priv->cfg.unknown2  = 1;

                priv->line_state    = 0;

                priv->bytes_in      = 0;
                priv->bytes_out     = 0;
                usb_set_serial_port_data(serial->port[i], priv);

                spin_lock_init (&priv->lock);
                for (j=0; j<NUM_URBS; j++) {
                        struct urb* urb = usb_alloc_urb(0, GFP_KERNEL);

                        priv->write_urb_pool[j] = urb;
                        if (urb == NULL) {
                                err("No more urbs???");
                                continue;
                        }

                        urb->transfer_buffer = NULL;
                        urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE,
                                                        GFP_KERNEL);
                        if (!urb->transfer_buffer) {
                                err("%s - out of memory for urb buffers.", __FUNCTION__);
                                continue;
                        }
                }

                /* priv->termios is left uninitalized until port opening */
                init_waitqueue_head(&serial->port[i]->write_wait);
        }
        
        return (0);
} /* klsi_105_startup */


static void klsi_105_shutdown (struct usb_serial *serial)
{
        int i;
        
        dbg("%s", __FUNCTION__);

        /* stop reads and writes on all ports */
        for (i=0; i < serial->num_ports; ++i) {
                struct klsi_105_private *priv = usb_get_serial_port_data(serial->port[i]);
                unsigned long flags;

                if (priv) {
                        /* kill our write urb pool */
                        int j;
                        struct urb **write_urbs = priv->write_urb_pool;
                        spin_lock_irqsave(&priv->lock,flags);

                        for (j = 0; j < NUM_URBS; j++) {
                                if (write_urbs[j]) {
                                        /* FIXME - uncomment the following
                                         * usb_kill_urb call when the host
                                         * controllers get fixed to set
                                         * urb->dev = NULL after the urb is
                                         * finished.  Otherwise this call
                                         * oopses. */
                                        /* usb_kill_urb(write_urbs[j]); */
                                        if (write_urbs[j]->transfer_buffer)
                                                    kfree(write_urbs[j]->transfer_buffer);
                                        usb_free_urb (write_urbs[j]);
                                }
                        }

                        spin_unlock_irqrestore (&priv->lock, flags);

                        kfree(priv);
                        usb_set_serial_port_data(serial->port[i], NULL);
                }
        }
} /* klsi_105_shutdown */

static int  klsi_105_open (struct usb_serial_port *port, struct file *filp)
{
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        int retval = 0;
        int rc;
        int i;
        unsigned long line_state;
        struct klsi_105_port_settings cfg;
        unsigned long flags;

        dbg("%s port %d", __FUNCTION__, port->number);

        /* force low_latency on so that our tty_push actually forces
         * the data through
         * port->tty->low_latency = 1; */

        /* Do a defined restart:
         * Set up sane default baud rate and send the 'READ_ON'
         * vendor command. 
         * FIXME: set modem line control (how?)
         * Then read the modem line control and store values in
         * priv->line_state.
         */
        cfg.pktlen   = 5;
        cfg.baudrate = kl5kusb105a_sio_b9600;
        cfg.databits = kl5kusb105a_dtb_8;
        cfg.unknown1 = 0;
        cfg.unknown2 = 1;
        klsi_105_chg_port_settings(port, &cfg);
        
        /* set up termios structure */
        spin_lock_irqsave (&priv->lock, flags);
        priv->termios.c_iflag = port->tty->termios->c_iflag;
        priv->termios.c_oflag = port->tty->termios->c_oflag;
        priv->termios.c_cflag = port->tty->termios->c_cflag;
        priv->termios.c_lflag = port->tty->termios->c_lflag;
        for (i=0; i<NCCS; i++)
                priv->termios.c_cc[i] = port->tty->termios->c_cc[i];
        priv->cfg.pktlen   = cfg.pktlen;
        priv->cfg.baudrate = cfg.baudrate;
        priv->cfg.databits = cfg.databits;
        priv->cfg.unknown1 = cfg.unknown1;
        priv->cfg.unknown2 = cfg.unknown2;
        spin_unlock_irqrestore (&priv->lock, flags);

        /* READ_ON and urb submission */
        usb_fill_bulk_urb(port->read_urb, port->serial->dev, 
                      usb_rcvbulkpipe(port->serial->dev,
                                      port->bulk_in_endpointAddress),
                      port->read_urb->transfer_buffer,
                      port->read_urb->transfer_buffer_length,
                      klsi_105_read_bulk_callback,
                      port);

        rc = usb_submit_urb(port->read_urb, GFP_KERNEL);
        if (rc) {
                err("%s - failed submitting read urb, error %d", __FUNCTION__, rc);
                retval = rc;
                goto exit;
        }

        rc = usb_control_msg(port->serial->dev,
                             usb_sndctrlpipe(port->serial->dev,0),
                             KL5KUSB105A_SIO_CONFIGURE,
                             USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
                             KL5KUSB105A_SIO_CONFIGURE_READ_ON,
                             0, /* index */
                             NULL,
                             0,
                             KLSI_TIMEOUT);
        if (rc < 0) {
                err("Enabling read failed (error = %d)", rc);
                retval = rc;
        } else 
                dbg("%s - enabled reading", __FUNCTION__);

        rc = klsi_105_get_line_state(port, &line_state);
        if (rc >= 0) {
                spin_lock_irqsave (&priv->lock, flags);
                priv->line_state = line_state;
                spin_unlock_irqrestore (&priv->lock, flags);
                dbg("%s - read line state 0x%lx", __FUNCTION__, line_state);
                retval = 0;
        } else
                retval = rc;

exit:
        return retval;
} /* klsi_105_open */


static void klsi_105_close (struct usb_serial_port *port, struct file *filp)
{
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        int rc;

        dbg("%s port %d", __FUNCTION__, port->number);

        /* send READ_OFF */
        rc = usb_control_msg (port->serial->dev,
                              usb_sndctrlpipe(port->serial->dev, 0),
                              KL5KUSB105A_SIO_CONFIGURE,
                              USB_TYPE_VENDOR | USB_DIR_OUT,
                              KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
                              0, /* index */
                              NULL, 0,
                              KLSI_TIMEOUT);
        if (rc < 0)
                    err("Disabling read failed (error = %d)", rc);

        /* shutdown our bulk reads and writes */
        usb_kill_urb(port->write_urb);
        usb_kill_urb(port->read_urb);
        /* unlink our write pool */
        /* FIXME */
        /* wgg - do I need this? I think so. */
        usb_kill_urb(port->interrupt_in_urb);
        info("kl5kusb105 port stats: %ld bytes in, %ld bytes out", priv->bytes_in, priv->bytes_out);
} /* klsi_105_close */


/* We need to write a complete 64-byte data block and encode the
 * number actually sent in the first double-byte, LSB-order. That 
 * leaves at most 62 bytes of payload.
 */
#define KLSI_105_DATA_OFFSET    2   /* in the bulk urb data block */


static int klsi_105_write (struct usb_serial_port *port,
                           const unsigned char *buf, int count)
{
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        int result, size;
        int bytes_sent=0;

        dbg("%s - port %d", __FUNCTION__, port->number);

        while (count > 0) {
                /* try to find a free urb (write 0 bytes if none) */
                struct urb *urb = NULL;
                unsigned long flags;
                int i;
                /* since the pool is per-port we might not need the spin lock !? */
                spin_lock_irqsave (&priv->lock, flags);
                for (i=0; i<NUM_URBS; i++) {
                        if (priv->write_urb_pool[i]->status != -EINPROGRESS) {
                                urb = priv->write_urb_pool[i];
                                dbg("%s - using pool URB %d", __FUNCTION__, i);
                                break;
                        }
                }
                spin_unlock_irqrestore (&priv->lock, flags);

                if (urb==NULL) {
                        dbg("%s - no more free urbs", __FUNCTION__);
                        goto exit;
                }

                if (urb->transfer_buffer == NULL) {
                        urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
                        if (urb->transfer_buffer == NULL) {
                                err("%s - no more kernel memory...", __FUNCTION__);
                                goto exit;
                        }
                }

                size = min (count, port->bulk_out_size - KLSI_105_DATA_OFFSET);
                size = min (size, URB_TRANSFER_BUFFER_SIZE - KLSI_105_DATA_OFFSET);

                memcpy (urb->transfer_buffer + KLSI_105_DATA_OFFSET, buf, size);

                /* write payload size into transfer buffer */
                ((__u8 *)urb->transfer_buffer)[0] = (__u8) (size & 0xFF);
                ((__u8 *)urb->transfer_buffer)[1] = (__u8) ((size & 0xFF00)>>8);

                /* set up our urb */
                usb_fill_bulk_urb(urb, port->serial->dev,
                              usb_sndbulkpipe(port->serial->dev,
                                              port->bulk_out_endpointAddress),
                              urb->transfer_buffer,
                              URB_TRANSFER_BUFFER_SIZE,
                              klsi_105_write_bulk_callback,
                              port);

                /* send the data out the bulk port */
                result = usb_submit_urb(urb, GFP_ATOMIC);
                if (result) {
                        err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
                        goto exit;
                }
                buf += size;
                bytes_sent += size;
                count -= size;
        }
exit:
        /* lockless, but it's for debug info only... */
        priv->bytes_out+=bytes_sent;

        return bytes_sent;      /* that's how much we wrote */
} /* klsi_105_write */

static void klsi_105_write_bulk_callback ( struct urb *urb, struct pt_regs *regs)
{
        struct usb_serial_port *port = (struct usb_serial_port *)urb->context;

        dbg("%s - port %d", __FUNCTION__, port->number);
        
        if (urb->status) {
                dbg("%s - nonzero write bulk status received: %d", __FUNCTION__,
                    urb->status);
                return;
        }

        /* from generic_write_bulk_callback */
        schedule_work(&port->work);
} /* klsi_105_write_bulk_completion_callback */


/* return number of characters currently in the writing process */
static int klsi_105_chars_in_buffer (struct usb_serial_port *port)
{
        int chars = 0;
        int i;
        unsigned long flags;
        struct klsi_105_private *priv = usb_get_serial_port_data(port);

        spin_lock_irqsave (&priv->lock, flags);

        for (i = 0; i < NUM_URBS; ++i) {
                if (priv->write_urb_pool[i]->status == -EINPROGRESS) {
                        chars += URB_TRANSFER_BUFFER_SIZE;
                }
        }

        spin_unlock_irqrestore (&priv->lock, flags);

        dbg("%s - returns %d", __FUNCTION__, chars);
        return (chars);
}

static int klsi_105_write_room (struct usb_serial_port *port)
{
        unsigned long flags;
        int i;
        int room = 0;
        struct klsi_105_private *priv = usb_get_serial_port_data(port);

        spin_lock_irqsave (&priv->lock, flags);
        for (i = 0; i < NUM_URBS; ++i) {
                if (priv->write_urb_pool[i]->status != -EINPROGRESS) {
                        room += URB_TRANSFER_BUFFER_SIZE;
                }
        }

        spin_unlock_irqrestore (&priv->lock, flags);

        dbg("%s - returns %d", __FUNCTION__, room);
        return (room);
}



static void klsi_105_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
{
        struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        struct tty_struct *tty;
        unsigned char *data = urb->transfer_buffer;
        int rc;

        dbg("%s - port %d", __FUNCTION__, port->number);

        /* The urb might have been killed. */
        if (urb->status) {
                dbg("%s - nonzero read bulk status received: %d", __FUNCTION__,
                    urb->status);
                return;
        }
        
        /* The data received is again preceded by a length double-byte in LSB-
         * first order (see klsi_105_write() )
         */
        if (urb->actual_length == 0) {
                /* empty urbs seem to happen, we ignore them */
                /* dbg("%s - emtpy URB", __FUNCTION__); */
               ;
        } else if (urb->actual_length <= 2) {
                dbg("%s - size %d URB not understood", __FUNCTION__,
                    urb->actual_length);
                usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
                                      urb->actual_length, data);
        } else {
                int i;
                int bytes_sent = ((__u8 *) data)[0] +
                                 ((unsigned int) ((__u8 *) data)[1] << 8);
                tty = port->tty;
                /* we should immediately resubmit the URB, before attempting
                 * to pass the data on to the tty layer. But that needs locking
                 * against re-entry an then mixed-up data because of
                 * intermixed tty_flip_buffer_push()s
                 * FIXME
                 */ 
                usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
                                      urb->actual_length, data);

                if (bytes_sent + 2 > urb->actual_length) {
                        dbg("%s - trying to read more data than available"
                            " (%d vs. %d)", __FUNCTION__,
                            bytes_sent+2, urb->actual_length);
                        /* cap at implied limit */
                        bytes_sent = urb->actual_length - 2;
                }

                for (i = 2; i < 2+bytes_sent; i++) {
                        /* if we insert more than TTY_FLIPBUF_SIZE characters,
                         * we drop them. */
                        if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
                                tty_flip_buffer_push(tty);
                        }
                        /* this doesn't actually push the data through unless 
                         * tty->low_latency is set */
                        tty_insert_flip_char(tty, ((__u8*) data)[i], 0);
                }
                tty_flip_buffer_push(tty);

                /* again lockless, but debug info only */
                priv->bytes_in += bytes_sent;
        }
        /* Continue trying to always read  */
        usb_fill_bulk_urb(port->read_urb, port->serial->dev, 
                      usb_rcvbulkpipe(port->serial->dev,
                                      port->bulk_in_endpointAddress),
                      port->read_urb->transfer_buffer,
                      port->read_urb->transfer_buffer_length,
                      klsi_105_read_bulk_callback,
                      port);
        rc = usb_submit_urb(port->read_urb, GFP_ATOMIC);
        if (rc)
                err("%s - failed resubmitting read urb, error %d", __FUNCTION__, rc);
} /* klsi_105_read_bulk_callback */


static void klsi_105_set_termios (struct usb_serial_port *port,
                                  struct termios *old_termios)
{
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        unsigned int iflag = port->tty->termios->c_iflag;
        unsigned int old_iflag = old_termios->c_iflag;
        unsigned int cflag = port->tty->termios->c_cflag;
        unsigned int old_cflag = old_termios->c_cflag;
        struct klsi_105_port_settings cfg;
        unsigned long flags;
        
        /* lock while we are modifying the settings */
        spin_lock_irqsave (&priv->lock, flags);
        
        /*
         * Update baud rate
         */
        if( (cflag & CBAUD) != (old_cflag & CBAUD) ) {
                /* reassert DTR and (maybe) RTS on transition from B0 */
                if( (old_cflag & CBAUD) == B0 ) {
                        dbg("%s: baud was B0", __FUNCTION__);
#if 0
                        priv->control_state |= TIOCM_DTR;
                        /* don't set RTS if using hardware flow control */
                        if (!(old_cflag & CRTSCTS)) {
                                priv->control_state |= TIOCM_RTS;
                        }
                        mct_u232_set_modem_ctrl(serial, priv->control_state);
#endif
                }
                
                switch(cflag & CBAUD) {
                case B0: /* handled below */
                        break;
                case B1200: priv->cfg.baudrate = kl5kusb105a_sio_b1200;
                        break;
                case B2400: priv->cfg.baudrate = kl5kusb105a_sio_b2400;
                        break;
                case B4800: priv->cfg.baudrate = kl5kusb105a_sio_b4800;
                        break;
                case B9600: priv->cfg.baudrate = kl5kusb105a_sio_b9600;
                        break;
                case B19200: priv->cfg.baudrate = kl5kusb105a_sio_b19200;
                        break;
                case B38400: priv->cfg.baudrate = kl5kusb105a_sio_b38400;
                        break;
                case B57600: priv->cfg.baudrate = kl5kusb105a_sio_b57600;
                        break;
                case B115200: priv->cfg.baudrate = kl5kusb105a_sio_b115200;
                        break;
                default:
                        err("KLSI USB->Serial converter:"
                            " unsupported baudrate request, using default"
                            " of 9600");
                        priv->cfg.baudrate = kl5kusb105a_sio_b9600;
                        break;
                }
                if ((cflag & CBAUD) == B0 ) {
                        dbg("%s: baud is B0", __FUNCTION__);
                        /* Drop RTS and DTR */
                        /* maybe this should be simulated by sending read
                         * disable and read enable messages?
                         */
                        ;
#if 0
                        priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
                        mct_u232_set_modem_ctrl(serial, priv->control_state);
#endif
                }
        }

        if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
                /* set the number of data bits */
                switch (cflag & CSIZE) {
                case CS5:
                        dbg("%s - 5 bits/byte not supported", __FUNCTION__);
                        spin_unlock_irqrestore (&priv->lock, flags);
                        return ;
                case CS6:
                        dbg("%s - 6 bits/byte not supported", __FUNCTION__);
                        spin_unlock_irqrestore (&priv->lock, flags);
                        return ;
                case CS7:
                        priv->cfg.databits = kl5kusb105a_dtb_7;
                        break;
                case CS8:
                        priv->cfg.databits = kl5kusb105a_dtb_8;
                        break;
                default:
                        err("CSIZE was not CS5-CS8, using default of 8");
                        priv->cfg.databits = kl5kusb105a_dtb_8;
                        break;
                }
        }

        /*
         * Update line control register (LCR)
         */
        if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
            || (cflag & CSTOPB) != (old_cflag & CSTOPB) ) {
                
#if 0
                priv->last_lcr = 0;

                /* set the parity */
                if (cflag & PARENB)
                        priv->last_lcr |= (cflag & PARODD) ?
                                MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
                else
                        priv->last_lcr |= MCT_U232_PARITY_NONE;

                /* set the number of stop bits */
                priv->last_lcr |= (cflag & CSTOPB) ?
                        MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;

                mct_u232_set_line_ctrl(serial, priv->last_lcr);
#endif
                ;
        }
        
        /*
         * Set flow control: well, I do not really now how to handle DTR/RTS.
         * Just do what we have seen with SniffUSB on Win98.
         */
        if( (iflag & IXOFF) != (old_iflag & IXOFF)
            || (iflag & IXON) != (old_iflag & IXON)
            ||  (cflag & CRTSCTS) != (old_cflag & CRTSCTS) ) {
                
                /* Drop DTR/RTS if no flow control otherwise assert */
#if 0
                if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS) )
                        priv->control_state |= TIOCM_DTR | TIOCM_RTS;
                else
                        priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
                mct_u232_set_modem_ctrl(serial, priv->control_state);
#endif
                ;
        }
        memcpy (&cfg, &priv->cfg, sizeof(cfg));
        spin_unlock_irqrestore (&priv->lock, flags);
        
        /* now commit changes to device */
        klsi_105_chg_port_settings(port, &cfg);
} /* klsi_105_set_termios */


#if 0
static void mct_u232_break_ctl( struct usb_serial_port *port, int break_state )
{
        struct usb_serial *serial = port->serial;
        struct mct_u232_private *priv = (struct mct_u232_private *)port->private;
        unsigned char lcr = priv->last_lcr;

        dbg("%sstate=%d", __FUNCTION__, break_state);

        if (break_state)
                lcr |= MCT_U232_SET_BREAK;

        mct_u232_set_line_ctrl(serial, lcr);
} /* mct_u232_break_ctl */
#endif

static int klsi_105_tiocmget (struct usb_serial_port *port, struct file *file)
{
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
        int rc;
        unsigned long line_state;
        dbg("%s - request, just guessing", __FUNCTION__);

        rc = klsi_105_get_line_state(port, &line_state);
        if (rc < 0) {
                err("Reading line control failed (error = %d)", rc);
                /* better return value? EAGAIN? */
                return rc;
        }

        spin_lock_irqsave (&priv->lock, flags);
        priv->line_state = line_state;
        spin_unlock_irqrestore (&priv->lock, flags);
        dbg("%s - read line state 0x%lx", __FUNCTION__, line_state);
        return (int)line_state;
}

static int klsi_105_tiocmset (struct usb_serial_port *port, struct file *file,
                              unsigned int set, unsigned int clear)
{
        int retval = -EINVAL;
        
        dbg("%s", __FUNCTION__);

/* if this ever gets implemented, it should be done something like this:
        struct usb_serial *serial = port->serial;
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        unsigned long flags;
        int control;

        spin_lock_irqsave (&priv->lock, flags);
        if (set & TIOCM_RTS)
                priv->control_state |= TIOCM_RTS;
        if (set & TIOCM_DTR)
                priv->control_state |= TIOCM_DTR;
        if (clear & TIOCM_RTS)
                priv->control_state &= ~TIOCM_RTS;
        if (clear & TIOCM_DTR)
                priv->control_state &= ~TIOCM_DTR;
        control = priv->control_state;
        spin_unlock_irqrestore (&priv->lock, flags);
        retval = mct_u232_set_modem_ctrl(serial, control);
*/
        return retval;
}
                                        
static int klsi_105_ioctl (struct usb_serial_port *port, struct file * file,
                           unsigned int cmd, unsigned long arg)
{
        struct klsi_105_private *priv = usb_get_serial_port_data(port);
        void __user *user_arg = (void __user *)arg;
        
        dbg("%scmd=0x%x", __FUNCTION__, cmd);

        /* Based on code from acm.c and others */
        switch (cmd) {
        case TIOCMIWAIT:
                /* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
                /* TODO */
                dbg("%s - TIOCMIWAIT not handled", __FUNCTION__);
                return -ENOIOCTLCMD;
        case TIOCGICOUNT:
                /* return count of modemline transitions */
                /* TODO */
                dbg("%s - TIOCGICOUNT not handled", __FUNCTION__);
                return -ENOIOCTLCMD;
        case TCGETS:
                /* return current info to caller */
                dbg("%s - TCGETS data faked/incomplete", __FUNCTION__);

                if (!access_ok(VERIFY_WRITE, user_arg, sizeof(struct termios)))
                        return -EFAULT;

                if (kernel_termios_to_user_termios((struct termios __user *)arg,
                                                   &priv->termios))
                        return -EFAULT;
                return 0;
        case TCSETS:
                /* set port termios to the one given by the user */
                dbg("%s - TCSETS not handled", __FUNCTION__);

                if (!access_ok(VERIFY_READ, user_arg, sizeof(struct termios)))
                        return -EFAULT;

                if (user_termios_to_kernel_termios(&priv->termios,
                                                   (struct termios __user *)arg))
                        return -EFAULT;
                klsi_105_set_termios(port, &priv->termios);
                return 0;
        case TCSETSW: {
                /* set port termios and try to wait for completion of last
                 * write operation */
                /* We guess here. If there are not too many write urbs
                 * outstanding, we lie. */
                /* what is the right way to wait here? schedule() ? */
                /*
                while (klsi_105_chars_in_buffer(port) > (NUM_URBS / 4 ) * URB_TRANSFER_BUFFER_SIZE)
                            schedule();
                 */
                return -ENOIOCTLCMD;
                      }
        default:
                dbg("%s: arg not supported - 0x%04x", __FUNCTION__,cmd);
                return(-ENOIOCTLCMD);
                break;
        }
        return 0;
} /* klsi_105_ioctl */

static void klsi_105_throttle (struct usb_serial_port *port)
{
        dbg("%s - port %d", __FUNCTION__, port->number);
        usb_kill_urb(port->read_urb);
}

static void klsi_105_unthrottle (struct usb_serial_port *port)
{
        int result;

        dbg("%s - port %d", __FUNCTION__, port->number);

        port->read_urb->dev = port->serial->dev;
        result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
        if (result)
                err("%s - failed submitting read urb, error %d", __FUNCTION__,
                    result);
}



static int __init klsi_105_init (void)
{
        int retval;
        retval = usb_serial_register(&kl5kusb105d_device);
        if (retval)
                goto failed_usb_serial_register;
        retval = usb_register(&kl5kusb105d_driver);
        if (retval)
                goto failed_usb_register;

        info(DRIVER_DESC " " DRIVER_VERSION);
        return 0;
failed_usb_register:
        usb_serial_deregister(&kl5kusb105d_device);
failed_usb_serial_register:
        return retval;
}


static void __exit klsi_105_exit (void)
{
        usb_deregister (&kl5kusb105d_driver);
        usb_serial_deregister (&kl5kusb105d_device);
}


module_init (klsi_105_init);
module_exit (klsi_105_exit);

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


module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "enable extensive debugging messages");

/* vim: set sts=8 ts=8 sw=8: */