drivers/usb/serial/kl5kusb105.c

   1 /*
   2  * KLSI KL5KUSB105 chip RS232 converter driver
   3  *
   4  *   Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
   5  *   Copyright (C) 2001 Utz-Uwe Haus <haus@uuhaus.de>
   6  *
   7  *   This program is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU General Public License as published by
   9  *   the Free Software Foundation; either version 2 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  * All information about the device was acquired using SniffUSB ans snoopUSB
  13  * on Windows98.
  14  * It was written out of frustration with the PalmConnect USB Serial adapter
  15  * sold by Palm Inc.
  16  * Neither Palm, nor their contractor (MCCI) or their supplier (KLSI) provided
  17  * information that was not already available.
  18  *
  19  * It seems that KLSI bought some silicon-design information from ScanLogic,
  20  * whose SL11R processor is at the core of the KL5KUSB chipset from KLSI.
  21  * KLSI has firmware available for their devices; it is probable that the
  22  * firmware differs from that used by KLSI in their products. If you have an
  23  * original KLSI device and can provide some information on it, I would be
  24  * most interested in adding support for it here. If you have any information
  25  * on the protocol used (or find errors in my reverse-engineered stuff), please
  26  * let me know.
  27  *
  28  * The code was only tested with a PalmConnect USB adapter; if you
  29  * are adventurous, try it with any KLSI-based device and let me know how it
  30  * breaks so that I can fix it!
  31  */
  32
  33 /* TODO:
  34  *      check modem line signals
  35  *      implement handshaking or decide that we do not support it
  36  */
  37
  38 #include <linux/kernel.h>
  39 #include <linux/errno.h>
  40 #include <linux/init.h>
  41 #include <linux/slab.h>
  42 #include <linux/tty.h>
  43 #include <linux/tty_driver.h>
  44 #include <linux/tty_flip.h>
  45 #include <linux/module.h>
  46 #include <linux/uaccess.h>
  47 #include <asm/unaligned.h>
  48 #include <linux/usb.h>
  49 #include <linux/usb/serial.h>
  50 #include "kl5kusb105.h"
  51
  52 #define DRIVER_AUTHOR "Utz-Uwe Haus <haus@uuhaus.de>, Johan Hovold <jhovold@gmail.com>"
  53 #define DRIVER_DESC "KLSI KL5KUSB105 chipset USB->Serial Converter driver"
  54
  55
  56 /*
  57  * Function prototypes
  58  */
  59 static int klsi_105_port_probe(struct usb_serial_port *port);
  60 static int klsi_105_port_remove(struct usb_serial_port *port);
  61 static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port);
  62 static void klsi_105_close(struct usb_serial_port *port);
  63 static void klsi_105_set_termios(struct tty_struct *tty,
  64                         struct usb_serial_port *port, struct ktermios *old);
  65 static int  klsi_105_tiocmget(struct tty_struct *tty);
  66 static int  klsi_105_tiocmset(struct tty_struct *tty,
  67                         unsigned int set, unsigned int clear);
  68 static void klsi_105_process_read_urb(struct urb *urb);
  69 static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
  70                                                 void *dest, size_t size);
  71
  72 /*
  73  * All of the device info needed for the KLSI converters.
  74  */
  75 static const struct usb_device_id id_table[] = {
  76         { USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
  77         { USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
  78         { }             /* Terminating entry */
  79 };
  80
  81 MODULE_DEVICE_TABLE(usb, id_table);
  82
  83 static struct usb_serial_driver kl5kusb105d_device = {
  84         .driver = {
  85                 .owner =        THIS_MODULE,
  86                 .name =         "kl5kusb105d",
  87         },
  88         .description =          "KL5KUSB105D / PalmConnect",
  89         .id_table =             id_table,
  90         .num_ports =            1,
  91         .bulk_out_size =        64,
  92         .open =                 klsi_105_open,
  93         .close =                klsi_105_close,
  94         .set_termios =          klsi_105_set_termios,
  95         /*.break_ctl =          klsi_105_break_ctl,*/
  96         .tiocmget =             klsi_105_tiocmget,
  97         .tiocmset =             klsi_105_tiocmset,
  98         .port_probe =           klsi_105_port_probe,
  99         .port_remove =          klsi_105_port_remove,
 100         .throttle =             usb_serial_generic_throttle,
 101         .unthrottle =           usb_serial_generic_unthrottle,
 102         .process_read_urb =     klsi_105_process_read_urb,
 103         .prepare_write_buffer = klsi_105_prepare_write_buffer,
 104 };
 105
 106 static struct usb_serial_driver * const serial_drivers[] = {
 107         &kl5kusb105d_device, NULL
 108 };
 109
 110 struct klsi_105_port_settings {
 111         __u8    pktlen;         /* always 5, it seems */
 112         __u8    baudrate;
 113         __u8    databits;
 114         __u8    unknown1;
 115         __u8    unknown2;
 116 } __attribute__ ((packed));
 117
 118 struct klsi_105_private {
 119         struct klsi_105_port_settings   cfg;
 120         struct ktermios                 termios;
 121         unsigned long                   line_state; /* modem line settings */
 122         spinlock_t                      lock;
 123 };
 124
 125
 126 /*
 127  * Handle vendor specific USB requests
 128  */
 129
 130
 131 #define KLSI_TIMEOUT     5000 /* default urb timeout */
 132
 133 static int klsi_105_chg_port_settings(struct usb_serial_port *port,
 134                                       struct klsi_105_port_settings *settings)
 135 {
 136         int rc;
 137
 138         rc = usb_control_msg(port->serial->dev,
 139                         usb_sndctrlpipe(port->serial->dev, 0),
 140                         KL5KUSB105A_SIO_SET_DATA,
 141                         USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
 142                         0, /* value */
 143                         0, /* index */
 144                         settings,
 145                         sizeof(struct klsi_105_port_settings),
 146                         KLSI_TIMEOUT);
 147         if (rc < 0)
 148                 dev_err(&port->dev,
 149                         "Change port settings failed (error = %d)\n", rc);
 150         dev_info(&port->serial->dev->dev,
 151                  "%d byte block, baudrate %x, databits %d, u1 %d, u2 %d\n",
 152                  settings->pktlen, settings->baudrate, settings->databits,
 153                  settings->unknown1, settings->unknown2);
 154         return rc;
 155 }
 156
 157 /* translate a 16-bit status value from the device to linux's TIO bits */
 158 static unsigned long klsi_105_status2linestate(const __u16 status)
 159 {
 160         unsigned long res = 0;
 161
 162         res =   ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
 163               | ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
 164               ;
 165
 166         return res;
 167 }
 168
 169 /*
 170  * Read line control via vendor command and return result through
 171  * *line_state_p
 172  */
 173 /* It seems that the status buffer has always only 2 bytes length */
 174 #define KLSI_STATUSBUF_LEN      2
 175 static int klsi_105_get_line_state(struct usb_serial_port *port,
 176                                    unsigned long *line_state_p)
 177 {
 178         int rc;
 179         u8 *status_buf;
 180         __u16 status;
 181
 182         dev_info(&port->serial->dev->dev, "sending SIO Poll request\n");
 183
 184         status_buf = kmalloc(KLSI_STATUSBUF_LEN, GFP_KERNEL);
 185         if (!status_buf)
 186                 return -ENOMEM;
 187
 188         status_buf[0] = 0xff;
 189         status_buf[1] = 0xff;
 190         rc = usb_control_msg(port->serial->dev,
 191                              usb_rcvctrlpipe(port->serial->dev, 0),
 192                              KL5KUSB105A_SIO_POLL,
 193                              USB_TYPE_VENDOR | USB_DIR_IN,
 194                              0, /* value */
 195                              0, /* index */
 196                              status_buf, KLSI_STATUSBUF_LEN,
 197                              10000
 198                              );
 199         if (rc < 0)
 200                 dev_err(&port->dev, "Reading line status failed (error = %d)\n",
 201                         rc);
 202         else {
 203                 status = get_unaligned_le16(status_buf);
 204
 205                 dev_info(&port->serial->dev->dev, "read status %x %x",
 206                          status_buf[0], status_buf[1]);
 207
 208                 *line_state_p = klsi_105_status2linestate(status);
 209         }
 210
 211         kfree(status_buf);
 212         return rc;
 213 }
 214
 215
 216 /*
 217  * Driver's tty interface functions
 218  */
 219
 220 static int klsi_105_port_probe(struct usb_serial_port *port)
 221 {
 222         struct klsi_105_private *priv;
 223
 224         priv = kmalloc(sizeof(*priv), GFP_KERNEL);
 225         if (!priv)
 226                 return -ENOMEM;
 227
 228         /* set initial values for control structures */
 229         priv->cfg.pktlen    = 5;
 230         priv->cfg.baudrate  = kl5kusb105a_sio_b9600;
 231         priv->cfg.databits  = kl5kusb105a_dtb_8;
 232         priv->cfg.unknown1  = 0;
 233         priv->cfg.unknown2  = 1;
 234
 235         priv->line_state    = 0;
 236
 237         spin_lock_init(&priv->lock);
 238
 239         /* priv->termios is left uninitialized until port opening */
 240
 241         usb_set_serial_port_data(port, priv);
 242
 243         return 0;
 244 }
 245
 246 static int klsi_105_port_remove(struct usb_serial_port *port)
 247 {
 248         struct klsi_105_private *priv;
 249
 250         priv = usb_get_serial_port_data(port);
 251         kfree(priv);
 252
 253         return 0;
 254 }
 255
 256 static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port)
 257 {
 258         struct klsi_105_private *priv = usb_get_serial_port_data(port);
 259         int retval = 0;
 260         int rc;
 261         int i;
 262         unsigned long line_state;
 263         struct klsi_105_port_settings *cfg;
 264         unsigned long flags;
 265
 266         /* Do a defined restart:
 267          * Set up sane default baud rate and send the 'READ_ON'
 268          * vendor command.
 269          * FIXME: set modem line control (how?)
 270          * Then read the modem line control and store values in
 271          * priv->line_state.
 272          */
 273         cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
 274         if (!cfg)
 275                 return -ENOMEM;
 276
 277         cfg->pktlen   = 5;
 278         cfg->baudrate = kl5kusb105a_sio_b9600;
 279         cfg->databits = kl5kusb105a_dtb_8;
 280         cfg->unknown1 = 0;
 281         cfg->unknown2 = 1;
 282         klsi_105_chg_port_settings(port, cfg);
 283
 284         /* set up termios structure */
 285         spin_lock_irqsave(&priv->lock, flags);
 286         priv->termios.c_iflag = tty->termios.c_iflag;
 287         priv->termios.c_oflag = tty->termios.c_oflag;
 288         priv->termios.c_cflag = tty->termios.c_cflag;
 289         priv->termios.c_lflag = tty->termios.c_lflag;
 290         for (i = 0; i < NCCS; i++)
 291                 priv->termios.c_cc[i] = tty->termios.c_cc[i];
 292         priv->cfg.pktlen   = cfg->pktlen;
 293         priv->cfg.baudrate = cfg->baudrate;
 294         priv->cfg.databits = cfg->databits;
 295         priv->cfg.unknown1 = cfg->unknown1;
 296         priv->cfg.unknown2 = cfg->unknown2;
 297         spin_unlock_irqrestore(&priv->lock, flags);
 298
 299         /* READ_ON and urb submission */
 300         rc = usb_serial_generic_open(tty, port);
 301         if (rc) {
 302                 retval = rc;
 303                 goto exit;
 304         }
 305
 306         rc = usb_control_msg(port->serial->dev,
 307                              usb_sndctrlpipe(port->serial->dev, 0),
 308                              KL5KUSB105A_SIO_CONFIGURE,
 309                              USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
 310                              KL5KUSB105A_SIO_CONFIGURE_READ_ON,
 311                              0, /* index */
 312                              NULL,
 313                              0,
 314                              KLSI_TIMEOUT);
 315         if (rc < 0) {
 316                 dev_err(&port->dev, "Enabling read failed (error = %d)\n", rc);
 317                 retval = rc;
 318         } else
 319                 dev_dbg(&port->dev, "%s - enabled reading\n", __func__);
 320
 321         rc = klsi_105_get_line_state(port, &line_state);
 322         if (rc >= 0) {
 323                 spin_lock_irqsave(&priv->lock, flags);
 324                 priv->line_state = line_state;
 325                 spin_unlock_irqrestore(&priv->lock, flags);
 326                 dev_dbg(&port->dev, "%s - read line state 0x%lx\n", __func__, line_state);
 327                 retval = 0;
 328         } else
 329                 retval = rc;
 330
 331 exit:
 332         kfree(cfg);
 333         return retval;
 334 }
 335
 336 static void klsi_105_close(struct usb_serial_port *port)
 337 {
 338         int rc;
 339
 340         /* send READ_OFF */
 341         rc = usb_control_msg(port->serial->dev,
 342                              usb_sndctrlpipe(port->serial->dev, 0),
 343                              KL5KUSB105A_SIO_CONFIGURE,
 344                              USB_TYPE_VENDOR | USB_DIR_OUT,
 345                              KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
 346                              0, /* index */
 347                              NULL, 0,
 348                              KLSI_TIMEOUT);
 349         if (rc < 0)
 350                 dev_err(&port->dev, "failed to disable read: %d\n", rc);
 351
 352         /* shutdown our bulk reads and writes */
 353         usb_serial_generic_close(port);
 354 }
 355
 356 /* We need to write a complete 64-byte data block and encode the
 357  * number actually sent in the first double-byte, LSB-order. That
 358  * leaves at most 62 bytes of payload.
 359  */
 360 #define KLSI_HDR_LEN            2
 361 static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
 362                                                 void *dest, size_t size)
 363 {
 364         unsigned char *buf = dest;
 365         int count;
 366
 367         count = kfifo_out_locked(&port->write_fifo, buf + KLSI_HDR_LEN, size,
 368                                                                 &port->lock);
 369         put_unaligned_le16(count, buf);
 370
 371         return count + KLSI_HDR_LEN;
 372 }
 373
 374 /* The data received is preceded by a length double-byte in LSB-first order.
 375  */
 376 static void klsi_105_process_read_urb(struct urb *urb)
 377 {
 378         struct usb_serial_port *port = urb->context;
 379         unsigned char *data = urb->transfer_buffer;
 380         unsigned len;
 381
 382         /* empty urbs seem to happen, we ignore them */
 383         if (!urb->actual_length)
 384                 return;
 385
 386         if (urb->actual_length <= KLSI_HDR_LEN) {
 387                 dev_dbg(&port->dev, "%s - malformed packet\n", __func__);
 388                 return;
 389         }
 390
 391         len = get_unaligned_le16(data);
 392         if (len > urb->actual_length - KLSI_HDR_LEN) {
 393                 dev_dbg(&port->dev, "%s - packet length mismatch\n", __func__);
 394                 len = urb->actual_length - KLSI_HDR_LEN;
 395         }
 396
 397         tty_insert_flip_string(&port->port, data + KLSI_HDR_LEN, len);
 398         tty_flip_buffer_push(&port->port);
 399 }
 400
 401 static void klsi_105_set_termios(struct tty_struct *tty,
 402                                  struct usb_serial_port *port,
 403                                  struct ktermios *old_termios)
 404 {
 405         struct klsi_105_private *priv = usb_get_serial_port_data(port);
 406         struct device *dev = &port->dev;
 407         unsigned int iflag = tty->termios.c_iflag;
 408         unsigned int old_iflag = old_termios->c_iflag;
 409         unsigned int cflag = tty->termios.c_cflag;
 410         unsigned int old_cflag = old_termios->c_cflag;
 411         struct klsi_105_port_settings *cfg;
 412         unsigned long flags;
 413         speed_t baud;
 414
 415         cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
 416         if (!cfg)
 417                 return;
 418
 419         /* lock while we are modifying the settings */
 420         spin_lock_irqsave(&priv->lock, flags);
 421
 422         /*
 423          * Update baud rate
 424          */
 425         baud = tty_get_baud_rate(tty);
 426
 427         if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
 428                 /* reassert DTR and (maybe) RTS on transition from B0 */
 429                 if ((old_cflag & CBAUD) == B0) {
 430                         dev_dbg(dev, "%s: baud was B0\n", __func__);
 431 #if 0
 432                         priv->control_state |= TIOCM_DTR;
 433                         /* don't set RTS if using hardware flow control */
 434                         if (!(old_cflag & CRTSCTS))
 435                                 priv->control_state |= TIOCM_RTS;
 436                         mct_u232_set_modem_ctrl(serial, priv->control_state);
 437 #endif
 438                 }
 439         }
 440         switch (baud) {
 441         case 0: /* handled below */
 442                 break;
 443         case 1200:
 444                 priv->cfg.baudrate = kl5kusb105a_sio_b1200;
 445                 break;
 446         case 2400:
 447                 priv->cfg.baudrate = kl5kusb105a_sio_b2400;
 448                 break;
 449         case 4800:
 450                 priv->cfg.baudrate = kl5kusb105a_sio_b4800;
 451                 break;
 452         case 9600:
 453                 priv->cfg.baudrate = kl5kusb105a_sio_b9600;
 454                 break;
 455         case 19200:
 456                 priv->cfg.baudrate = kl5kusb105a_sio_b19200;
 457                 break;
 458         case 38400:
 459                 priv->cfg.baudrate = kl5kusb105a_sio_b38400;
 460                 break;
 461         case 57600:
 462                 priv->cfg.baudrate = kl5kusb105a_sio_b57600;
 463                 break;
 464         case 115200:
 465                 priv->cfg.baudrate = kl5kusb105a_sio_b115200;
 466                 break;
 467         default:
 468                 dev_dbg(dev, "KLSI USB->Serial converter: unsupported baudrate request, using default of 9600");
 469                 priv->cfg.baudrate = kl5kusb105a_sio_b9600;
 470                 baud = 9600;
 471                 break;
 472         }
 473         if ((cflag & CBAUD) == B0) {
 474                 dev_dbg(dev, "%s: baud is B0\n", __func__);
 475                 /* Drop RTS and DTR */
 476                 /* maybe this should be simulated by sending read
 477                  * disable and read enable messages?
 478                  */
 479                 ;
 480 #if 0
 481                 priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
 482                 mct_u232_set_modem_ctrl(serial, priv->control_state);
 483 #endif
 484         }
 485         tty_encode_baud_rate(tty, baud, baud);
 486
 487         if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
 488                 /* set the number of data bits */
 489                 switch (cflag & CSIZE) {
 490                 case CS5:
 491                         dev_dbg(dev, "%s - 5 bits/byte not supported\n", __func__);
 492                         spin_unlock_irqrestore(&priv->lock, flags);
 493                         goto err;
 494                 case CS6:
 495                         dev_dbg(dev, "%s - 6 bits/byte not supported\n", __func__);
 496                         spin_unlock_irqrestore(&priv->lock, flags);
 497                         goto err;
 498                 case CS7:
 499                         priv->cfg.databits = kl5kusb105a_dtb_7;
 500                         break;
 501                 case CS8:
 502                         priv->cfg.databits = kl5kusb105a_dtb_8;
 503                         break;
 504                 default:
 505                         dev_err(dev, "CSIZE was not CS5-CS8, using default of 8\n");
 506                         priv->cfg.databits = kl5kusb105a_dtb_8;
 507                         break;
 508                 }
 509         }
 510
 511         /*
 512          * Update line control register (LCR)
 513          */
 514         if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
 515             || (cflag & CSTOPB) != (old_cflag & CSTOPB)) {
 516                 /* Not currently supported */
 517                 tty->termios.c_cflag &= ~(PARENB|PARODD|CSTOPB);
 518 #if 0
 519                 priv->last_lcr = 0;
 520
 521                 /* set the parity */
 522                 if (cflag & PARENB)
 523                         priv->last_lcr |= (cflag & PARODD) ?
 524                                 MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
 525                 else
 526                         priv->last_lcr |= MCT_U232_PARITY_NONE;
 527
 528                 /* set the number of stop bits */
 529                 priv->last_lcr |= (cflag & CSTOPB) ?
 530                         MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
 531
 532                 mct_u232_set_line_ctrl(serial, priv->last_lcr);
 533 #endif
 534                 ;
 535         }
 536         /*
 537          * Set flow control: well, I do not really now how to handle DTR/RTS.
 538          * Just do what we have seen with SniffUSB on Win98.
 539          */
 540         if ((iflag & IXOFF) != (old_iflag & IXOFF)
 541             || (iflag & IXON) != (old_iflag & IXON)
 542             ||  (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
 543                 /* Not currently supported */
 544                 tty->termios.c_cflag &= ~CRTSCTS;
 545                 /* Drop DTR/RTS if no flow control otherwise assert */
 546 #if 0
 547                 if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
 548                         priv->control_state |= TIOCM_DTR | TIOCM_RTS;
 549                 else
 550                         priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
 551                 mct_u232_set_modem_ctrl(serial, priv->control_state);
 552 #endif
 553                 ;
 554         }
 555         memcpy(cfg, &priv->cfg, sizeof(*cfg));
 556         spin_unlock_irqrestore(&priv->lock, flags);
 557
 558         /* now commit changes to device */
 559         klsi_105_chg_port_settings(port, cfg);
 560 err:
 561         kfree(cfg);
 562 }
 563
 564 #if 0
 565 static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
 566 {
 567         struct usb_serial_port *port = tty->driver_data;
 568         struct usb_serial *serial = port->serial;
 569         struct mct_u232_private *priv =
 570                                 (struct mct_u232_private *)port->private;
 571         unsigned char lcr = priv->last_lcr;
 572
 573         dev_dbg(&port->dev, "%s - state=%d\n", __func__, break_state);
 574
 575         /* LOCKING */
 576         if (break_state)
 577                 lcr |= MCT_U232_SET_BREAK;
 578
 579         mct_u232_set_line_ctrl(serial, lcr);
 580 }
 581 #endif
 582
 583 static int klsi_105_tiocmget(struct tty_struct *tty)
 584 {
 585         struct usb_serial_port *port = tty->driver_data;
 586         struct klsi_105_private *priv = usb_get_serial_port_data(port);
 587         unsigned long flags;
 588         int rc;
 589         unsigned long line_state;
 590
 591         rc = klsi_105_get_line_state(port, &line_state);
 592         if (rc < 0) {
 593                 dev_err(&port->dev,
 594                         "Reading line control failed (error = %d)\n", rc);
 595                 /* better return value? EAGAIN? */
 596                 return rc;
 597         }
 598
 599         spin_lock_irqsave(&priv->lock, flags);
 600         priv->line_state = line_state;
 601         spin_unlock_irqrestore(&priv->lock, flags);
 602         dev_dbg(&port->dev, "%s - read line state 0x%lx\n", __func__, line_state);
 603         return (int)line_state;
 604 }
 605
 606 static int klsi_105_tiocmset(struct tty_struct *tty,
 607                              unsigned int set, unsigned int clear)
 608 {
 609         int retval = -EINVAL;
 610
 611 /* if this ever gets implemented, it should be done something like this:
 612         struct usb_serial *serial = port->serial;
 613         struct klsi_105_private *priv = usb_get_serial_port_data(port);
 614         unsigned long flags;
 615         int control;
 616
 617         spin_lock_irqsave (&priv->lock, flags);
 618         if (set & TIOCM_RTS)
 619                 priv->control_state |= TIOCM_RTS;
 620         if (set & TIOCM_DTR)
 621                 priv->control_state |= TIOCM_DTR;
 622         if (clear & TIOCM_RTS)
 623                 priv->control_state &= ~TIOCM_RTS;
 624         if (clear & TIOCM_DTR)
 625                 priv->control_state &= ~TIOCM_DTR;
 626         control = priv->control_state;
 627         spin_unlock_irqrestore (&priv->lock, flags);
 628         retval = mct_u232_set_modem_ctrl(serial, control);
 629 */
 630         return retval;
 631 }
 632
 633 module_usb_serial_driver(serial_drivers, id_table);
 634
 635 MODULE_AUTHOR(DRIVER_AUTHOR);
 636 MODULE_DESCRIPTION(DRIVER_DESC);
 637 MODULE_LICENSE("GPL");