drivers/usb/serial/belkin_sa.c

   1 /*
   2  * Belkin USB Serial Adapter Driver
   3  *
   4  *  Copyright (C) 2000          William Greathouse (wgreathouse@smva.com)
   5  *  Copyright (C) 2000-2001     Greg Kroah-Hartman (greg@kroah.com)
   6  *
   7  *  This program is largely derived from work by the linux-usb group
   8  *  and associated source files.  Please see the usb/serial files for
   9  *  individual credits and copyrights.
  10  *
  11  *      This program is free software; you can redistribute it and/or modify
  12  *      it under the terms of the GNU General Public License as published by
  13  *      the Free Software Foundation; either version 2 of the License, or
  14  *      (at your option) any later version.
  15  *
  16  * See Documentation/usb/usb-serial.txt for more information on using this driver
  17  *
  18  * TODO:
  19  * -- Add true modem contol line query capability.  Currently we track the
  20  *    states reported by the interrupt and the states we request.
  21  * -- Add error reporting back to application for UART error conditions.
  22  *    Just point me at how to implement this and I'll do it. I've put the
  23  *    framework in, but haven't analyzed the "tty_flip" interface yet.
  24  * -- Add support for flush commands
  25  * -- Add everything that is missing :)
  26  *
  27  * 27-Nov-2001 gkh
  28  *      compressed all the differnent device entries into 1.
  29  *
  30  * 30-May-2001 gkh
  31  *      switched from using spinlock to a semaphore, which fixes lots of problems.
  32  *
  33  * 08-Apr-2001 gb
  34  *      - Identify version on module load.
  35  *
  36  * 12-Mar-2001 gkh
  37  *      - Added support for the GoHubs GO-COM232 device which is the same as the
  38  *        Peracom device.
  39  *
  40  * 06-Nov-2000 gkh
  41  *      - Added support for the old Belkin and Peracom devices.
  42  *      - Made the port able to be opened multiple times.
  43  *      - Added some defaults incase the line settings are things these devices
  44  *        can't support.
  45  *
  46  * 18-Oct-2000 William Greathouse
  47  *    Released into the wild (linux-usb-devel)
  48  *
  49  * 17-Oct-2000 William Greathouse
  50  *    Add code to recognize firmware version and set hardware flow control
  51  *    appropriately.  Belkin states that firmware prior to 3.05 does not
  52  *    operate correctly in hardware handshake mode.  I have verified this
  53  *    on firmware 2.05 -- for both RTS and DTR input flow control, the control
  54  *    line is not reset.  The test performed by the Belkin Win* driver is
  55  *    to enable hardware flow control for firmware 2.06 or greater and
  56  *    for 1.00 or prior.  I am only enabling for 2.06 or greater.
  57  *
  58  * 12-Oct-2000 William Greathouse
  59  *    First cut at supporting Belkin USB Serial Adapter F5U103
  60  *    I did not have a copy of the original work to support this
  61  *    adapter, so pardon any stupid mistakes.  All of the information
  62  *    I am using to write this driver was acquired by using a modified
  63  *    UsbSnoop on Windows2000 and from examining the other USB drivers.
  64  */
  65
  66 #include <linux/config.h>
  67 #include <linux/kernel.h>
  68 #include <linux/errno.h>
  69 #include <linux/init.h>
  70 #include <linux/slab.h>
  71 #include <linux/tty.h>
  72 #include <linux/tty_driver.h>
  73 #include <linux/tty_flip.h>
  74 #include <linux/module.h>
  75 #include <linux/spinlock.h>
  76 #include <asm/uaccess.h>
  77 #include <linux/usb.h>
  78 #include "usb-serial.h"
  79 #include "belkin_sa.h"
  80
  81 static int debug;
  82
  83 /*
  84  * Version Information
  85  */
  86 #define DRIVER_VERSION "v1.2"
  87 #define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
  88 #define DRIVER_DESC "USB Belkin Serial converter driver"
  89
  90 /* function prototypes for a Belkin USB Serial Adapter F5U103 */
  91 static int  belkin_sa_startup           (struct usb_serial *serial);
  92 static void belkin_sa_shutdown          (struct usb_serial *serial);
  93 static int  belkin_sa_open              (struct usb_serial_port *port, struct file *filp);
  94 static void belkin_sa_close             (struct usb_serial_port *port, struct file *filp);
  95 static void belkin_sa_read_int_callback (struct urb *urb, struct pt_regs *regs);
  96 static void belkin_sa_set_termios       (struct usb_serial_port *port, struct termios * old);
  97 static int  belkin_sa_ioctl             (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
  98 static void belkin_sa_break_ctl         (struct usb_serial_port *port, int break_state );
  99 static int  belkin_sa_tiocmget          (struct usb_serial_port *port, struct file *file);
 100 static int  belkin_sa_tiocmset          (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear);
 101
 102
 103 static struct usb_device_id id_table_combined [] = {
 104         { USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
 105         { USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
 106         { USB_DEVICE(PERACOM_VID, PERACOM_PID) },
 107         { USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
 108         { USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
 109         { USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
 110         { }                                                     /* Terminating entry */
 111 };
 112
 113 MODULE_DEVICE_TABLE (usb, id_table_combined);
 114
 115 static struct usb_driver belkin_driver = {
 116         .owner =        THIS_MODULE,
 117         .name =         "belkin",
 118         .probe =        usb_serial_probe,
 119         .disconnect =   usb_serial_disconnect,
 120         .id_table =     id_table_combined,
 121 };
 122
 123 /* All of the device info needed for the serial converters */
 124 static struct usb_serial_device_type belkin_device = {
 125         .owner =                THIS_MODULE,
 126         .name =                 "Belkin / Peracom / GoHubs USB Serial Adapter",
 127         .short_name =           "belkin",
 128         .id_table =             id_table_combined,
 129         .num_interrupt_in =     1,
 130         .num_bulk_in =          1,
 131         .num_bulk_out =         1,
 132         .num_ports =            1,
 133         .open =                 belkin_sa_open,
 134         .close =                belkin_sa_close,
 135         .read_int_callback =    belkin_sa_read_int_callback,    /* How we get the status info */
 136         .ioctl =                belkin_sa_ioctl,
 137         .set_termios =          belkin_sa_set_termios,
 138         .break_ctl =            belkin_sa_break_ctl,
 139         .tiocmget =             belkin_sa_tiocmget,
 140         .tiocmset =             belkin_sa_tiocmset,
 141         .attach =               belkin_sa_startup,
 142         .shutdown =             belkin_sa_shutdown,
 143 };
 144
 145
 146 struct belkin_sa_private {
 147         spinlock_t              lock;
 148         unsigned long           control_state;
 149         unsigned char           last_lsr;
 150         unsigned char           last_msr;
 151         int                     bad_flow_control;
 152 };
 153
 154
 155 /*
 156  * ***************************************************************************
 157  * Belkin USB Serial Adapter F5U103 specific driver functions
 158  * ***************************************************************************
 159  */
 160
 161 #define WDR_TIMEOUT 5000 /* default urb timeout */
 162
 163 /* assumes that struct usb_serial *serial is available */
 164 #define BSA_USB_CMD(c,v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
 165                                             (c), BELKIN_SA_SET_REQUEST_TYPE, \
 166                                             (v), 0, NULL, 0, WDR_TIMEOUT)
 167
 168 /* do some startup allocations not currently performed by usb_serial_probe() */
 169 static int belkin_sa_startup (struct usb_serial *serial)
 170 {
 171         struct usb_device *dev = serial->dev;
 172         struct belkin_sa_private *priv;
 173
 174         /* allocate the private data structure */
 175         priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
 176         if (!priv)
 177                 return (-1); /* error */
 178         /* set initial values for control structures */
 179         spin_lock_init(&priv->lock);
 180         priv->control_state = 0;
 181         priv->last_lsr = 0;
 182         priv->last_msr = 0;
 183         /* see comments at top of file */
 184         priv->bad_flow_control = (le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
 185         info("bcdDevice: %04x, bfc: %d", le16_to_cpu(dev->descriptor.bcdDevice), priv->bad_flow_control);
 186
 187         init_waitqueue_head(&serial->port[0]->write_wait);
 188         usb_set_serial_port_data(serial->port[0], priv);
 189
 190         return (0);
 191 }
 192
 193
 194 static void belkin_sa_shutdown (struct usb_serial *serial)
 195 {
 196         struct belkin_sa_private *priv;
 197         int i;
 198
 199         dbg ("%s", __FUNCTION__);
 200
 201         /* stop reads and writes on all ports */
 202         for (i=0; i < serial->num_ports; ++i) {
 203                 /* My special items, the standard routines free my urbs */
 204                 priv = usb_get_serial_port_data(serial->port[i]);
 205                 if (priv)
 206                         kfree(priv);
 207         }
 208 }
 209
 210
 211 static int  belkin_sa_open (struct usb_serial_port *port, struct file *filp)
 212 {
 213         int retval = 0;
 214
 215         dbg("%s port %d", __FUNCTION__, port->number);
 216
 217         /*Start reading from the device*/
 218         /* TODO: Look at possibility of submitting multiple URBs to device to
 219          *       enhance buffering.  Win trace shows 16 initial read URBs.
 220          */
 221         port->read_urb->dev = port->serial->dev;
 222         retval = usb_submit_urb(port->read_urb, GFP_KERNEL);
 223         if (retval) {
 224                 err("usb_submit_urb(read bulk) failed");
 225                 goto exit;
 226         }
 227
 228         port->interrupt_in_urb->dev = port->serial->dev;
 229         retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 230         if (retval) {
 231                 usb_kill_urb(port->read_urb);
 232                 err(" usb_submit_urb(read int) failed");
 233         }
 234
 235 exit:
 236         return retval;
 237 } /* belkin_sa_open */
 238
 239
 240 static void belkin_sa_close (struct usb_serial_port *port, struct file *filp)
 241 {
 242         dbg("%s port %d", __FUNCTION__, port->number);
 243
 244         /* shutdown our bulk reads and writes */
 245         usb_kill_urb(port->write_urb);
 246         usb_kill_urb(port->read_urb);
 247         usb_kill_urb(port->interrupt_in_urb);
 248 } /* belkin_sa_close */
 249
 250
 251 static void belkin_sa_read_int_callback (struct urb *urb, struct pt_regs *regs)
 252 {
 253         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 254         struct belkin_sa_private *priv;
 255         unsigned char *data = urb->transfer_buffer;
 256         int retval;
 257         unsigned long flags;
 258
 259         switch (urb->status) {
 260         case 0:
 261                 /* success */
 262                 break;
 263         case -ECONNRESET:
 264         case -ENOENT:
 265         case -ESHUTDOWN:
 266                 /* this urb is terminated, clean up */
 267                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 268                 return;
 269         default:
 270                 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 271                 goto exit;
 272         }
 273
 274         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
 275
 276         /* Handle known interrupt data */
 277         /* ignore data[0] and data[1] */
 278
 279         priv = usb_get_serial_port_data(port);
 280         spin_lock_irqsave(&priv->lock, flags);
 281         priv->last_msr = data[BELKIN_SA_MSR_INDEX];
 282
 283         /* Record Control Line states */
 284         if (priv->last_msr & BELKIN_SA_MSR_DSR)
 285                 priv->control_state |= TIOCM_DSR;
 286         else
 287                 priv->control_state &= ~TIOCM_DSR;
 288
 289         if (priv->last_msr & BELKIN_SA_MSR_CTS)
 290                 priv->control_state |= TIOCM_CTS;
 291         else
 292                 priv->control_state &= ~TIOCM_CTS;
 293
 294         if (priv->last_msr & BELKIN_SA_MSR_RI)
 295                 priv->control_state |= TIOCM_RI;
 296         else
 297                 priv->control_state &= ~TIOCM_RI;
 298
 299         if (priv->last_msr & BELKIN_SA_MSR_CD)
 300                 priv->control_state |= TIOCM_CD;
 301         else
 302                 priv->control_state &= ~TIOCM_CD;
 303
 304         /* Now to report any errors */
 305         priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
 306 #if 0
 307         /*
 308          * fill in the flip buffer here, but I do not know the relation
 309          * to the current/next receive buffer or characters.  I need
 310          * to look in to this before committing any code.
 311          */
 312         if (priv->last_lsr & BELKIN_SA_LSR_ERR) {
 313                 tty = port->tty;
 314                 /* Overrun Error */
 315                 if (priv->last_lsr & BELKIN_SA_LSR_OE) {
 316                 }
 317                 /* Parity Error */
 318                 if (priv->last_lsr & BELKIN_SA_LSR_PE) {
 319                 }
 320                 /* Framing Error */
 321                 if (priv->last_lsr & BELKIN_SA_LSR_FE) {
 322                 }
 323                 /* Break Indicator */
 324                 if (priv->last_lsr & BELKIN_SA_LSR_BI) {
 325                 }
 326         }
 327 #endif
 328         spin_unlock_irqrestore(&priv->lock, flags);
 329 exit:
 330         retval = usb_submit_urb (urb, GFP_ATOMIC);
 331         if (retval)
 332                 err ("%s - usb_submit_urb failed with result %d",
 333                      __FUNCTION__, retval);
 334 }
 335
 336 static void belkin_sa_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 337 {
 338         struct usb_serial *serial = port->serial;
 339         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 340         unsigned int iflag;
 341         unsigned int cflag;
 342         unsigned int old_iflag = 0;
 343         unsigned int old_cflag = 0;
 344         __u16 urb_value = 0; /* Will hold the new flags */
 345         unsigned long flags;
 346         unsigned long control_state;
 347         int bad_flow_control;
 348
 349         if ((!port->tty) || (!port->tty->termios)) {
 350                 dbg ("%s - no tty or termios structure", __FUNCTION__);
 351                 return;
 352         }
 353
 354         iflag = port->tty->termios->c_iflag;
 355         cflag = port->tty->termios->c_cflag;
 356
 357         /* get a local copy of the current port settings */
 358         spin_lock_irqsave(&priv->lock, flags);
 359         control_state = priv->control_state;
 360         bad_flow_control = priv->bad_flow_control;
 361         spin_unlock_irqrestore(&priv->lock, flags);
 362
 363         /* check that they really want us to change something */
 364         if (old_termios) {
 365                 if ((cflag == old_termios->c_cflag) &&
 366                     (RELEVANT_IFLAG(port->tty->termios->c_iflag) == RELEVANT_IFLAG(old_termios->c_iflag))) {
 367                         dbg("%s - nothing to change...", __FUNCTION__);
 368                         return;
 369                 }
 370                 old_iflag = old_termios->c_iflag;
 371                 old_cflag = old_termios->c_cflag;
 372         }
 373
 374         /* Set the baud rate */
 375         if( (cflag&CBAUD) != (old_cflag&CBAUD) ) {
 376                 /* reassert DTR and (maybe) RTS on transition from B0 */
 377                 if( (old_cflag&CBAUD) == B0 ) {
 378                         control_state |= (TIOCM_DTR|TIOCM_RTS);
 379                         if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
 380                                 err("Set DTR error");
 381                         /* don't set RTS if using hardware flow control */
 382                         if (!(old_cflag&CRTSCTS) )
 383                                 if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 1) < 0)
 384                                         err("Set RTS error");
 385                 }
 386
 387                 switch(cflag & CBAUD) {
 388                         case B0: /* handled below */ break;
 389                         case B300: urb_value = BELKIN_SA_BAUD(300); break;
 390                         case B600: urb_value = BELKIN_SA_BAUD(600); break;
 391                         case B1200: urb_value = BELKIN_SA_BAUD(1200); break;
 392                         case B2400: urb_value = BELKIN_SA_BAUD(2400); break;
 393                         case B4800: urb_value = BELKIN_SA_BAUD(4800); break;
 394                         case B9600: urb_value = BELKIN_SA_BAUD(9600); break;
 395                         case B19200: urb_value = BELKIN_SA_BAUD(19200); break;
 396                         case B38400: urb_value = BELKIN_SA_BAUD(38400); break;
 397                         case B57600: urb_value = BELKIN_SA_BAUD(57600); break;
 398                         case B115200: urb_value = BELKIN_SA_BAUD(115200); break;
 399                         case B230400: urb_value = BELKIN_SA_BAUD(230400); break;
 400                         default: err("BELKIN USB Serial Adapter: unsupported baudrate request, using default of 9600");
 401                                 urb_value = BELKIN_SA_BAUD(9600); break;
 402                 }
 403                 if ((cflag & CBAUD) != B0 ) {
 404                         if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
 405                                 err("Set baudrate error");
 406                 } else {
 407                         /* Disable flow control */
 408                         if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, BELKIN_SA_FLOW_NONE) < 0)
 409                                 err("Disable flowcontrol error");
 410
 411                         /* Drop RTS and DTR */
 412                         control_state &= ~(TIOCM_DTR | TIOCM_RTS);
 413                         if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
 414                                 err("DTR LOW error");
 415                         if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
 416                                 err("RTS LOW error");
 417                 }
 418         }
 419
 420         /* set the parity */
 421         if( (cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD)) ) {
 422                 if (cflag & PARENB)
 423                         urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD : BELKIN_SA_PARITY_EVEN;
 424                 else
 425                         urb_value = BELKIN_SA_PARITY_NONE;
 426                 if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
 427                         err("Set parity error");
 428         }
 429
 430         /* set the number of data bits */
 431         if( (cflag&CSIZE) != (old_cflag&CSIZE) ) {
 432                 switch (cflag & CSIZE) {
 433                         case CS5: urb_value = BELKIN_SA_DATA_BITS(5); break;
 434                         case CS6: urb_value = BELKIN_SA_DATA_BITS(6); break;
 435                         case CS7: urb_value = BELKIN_SA_DATA_BITS(7); break;
 436                         case CS8: urb_value = BELKIN_SA_DATA_BITS(8); break;
 437                         default: err("CSIZE was not CS5-CS8, using default of 8");
 438                                 urb_value = BELKIN_SA_DATA_BITS(8);
 439                                 break;
 440                 }
 441                 if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
 442                         err("Set data bits error");
 443         }
 444
 445         /* set the number of stop bits */
 446         if( (cflag&CSTOPB) != (old_cflag&CSTOPB) ) {
 447                 urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2) : BELKIN_SA_STOP_BITS(1);
 448                 if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST, urb_value) < 0)
 449                         err("Set stop bits error");
 450         }
 451
 452         /* Set flow control */
 453         if( (iflag&IXOFF)   != (old_iflag&IXOFF)
 454         ||      (iflag&IXON)    != (old_iflag&IXON)
 455         ||  (cflag&CRTSCTS) != (old_cflag&CRTSCTS) ) {
 456                 urb_value = 0;
 457                 if ((iflag & IXOFF) || (iflag & IXON))
 458                         urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
 459                 else
 460                         urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
 461
 462                 if (cflag & CRTSCTS)
 463                         urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
 464                 else
 465                         urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
 466
 467                 if (bad_flow_control)
 468                         urb_value &= ~(BELKIN_SA_FLOW_IRTS);
 469
 470                 if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
 471                         err("Set flow control error");
 472         }
 473
 474         /* save off the modified port settings */
 475         spin_lock_irqsave(&priv->lock, flags);
 476         priv->control_state = control_state;
 477         spin_unlock_irqrestore(&priv->lock, flags);
 478 } /* belkin_sa_set_termios */
 479
 480
 481 static void belkin_sa_break_ctl( struct usb_serial_port *port, int break_state )
 482 {
 483         struct usb_serial *serial = port->serial;
 484
 485         if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
 486                 err("Set break_ctl %d", break_state);
 487 }
 488
 489
 490 static int belkin_sa_tiocmget (struct usb_serial_port *port, struct file *file)
 491 {
 492         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 493         unsigned long control_state;
 494         unsigned long flags;
 495
 496         dbg("%s", __FUNCTION__);
 497
 498         spin_lock_irqsave(&priv->lock, flags);
 499         control_state = priv->control_state;
 500         spin_unlock_irqrestore(&priv->lock, flags);
 501
 502         return control_state;
 503 }
 504
 505
 506 static int belkin_sa_tiocmset (struct usb_serial_port *port, struct file *file,
 507                                unsigned int set, unsigned int clear)
 508 {
 509         struct usb_serial *serial = port->serial;
 510         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 511         unsigned long control_state;
 512         unsigned long flags;
 513         int retval;
 514         int rts = 0;
 515         int dtr = 0;
 516
 517         dbg("%s", __FUNCTION__);
 518
 519         spin_lock_irqsave(&priv->lock, flags);
 520         control_state = priv->control_state;
 521
 522         if (set & TIOCM_RTS) {
 523                 control_state |= TIOCM_RTS;
 524                 rts = 1;
 525         }
 526         if (set & TIOCM_DTR) {
 527                 control_state |= TIOCM_DTR;
 528                 dtr = 1;
 529         }
 530         if (clear & TIOCM_RTS) {
 531                 control_state &= ~TIOCM_RTS;
 532                 rts = 0;
 533         }
 534         if (clear & TIOCM_DTR) {
 535                 control_state &= ~TIOCM_DTR;
 536                 dtr = 0;
 537         }
 538
 539         priv->control_state = control_state;
 540         spin_unlock_irqrestore(&priv->lock, flags);
 541
 542         retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
 543         if (retval < 0) {
 544                 err("Set RTS error %d", retval);
 545                 goto exit;
 546         }
 547
 548         retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
 549         if (retval < 0) {
 550                 err("Set DTR error %d", retval);
 551                 goto exit;
 552         }
 553 exit:
 554         return retval;
 555 }
 556
 557
 558 static int belkin_sa_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 559 {
 560         switch (cmd) {
 561         case TIOCMIWAIT:
 562                 /* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
 563                 /* TODO */
 564                 return( 0 );
 565
 566         case TIOCGICOUNT:
 567                 /* return count of modemline transitions */
 568                 /* TODO */
 569                 return 0;
 570
 571         default:
 572                 dbg("belkin_sa_ioctl arg not supported - 0x%04x",cmd);
 573                 return(-ENOIOCTLCMD);
 574                 break;
 575         }
 576         return 0;
 577 } /* belkin_sa_ioctl */
 578
 579
 580 static int __init belkin_sa_init (void)
 581 {
 582         int retval;
 583         retval = usb_serial_register(&belkin_device);
 584         if (retval)
 585                 goto failed_usb_serial_register;
 586         retval = usb_register(&belkin_driver);
 587         if (retval)
 588                 goto failed_usb_register;
 589         info(DRIVER_DESC " " DRIVER_VERSION);
 590         return 0;
 591 failed_usb_register:
 592         usb_serial_deregister(&belkin_device);
 593 failed_usb_serial_register:
 594         return retval;
 595 }
 596
 597
 598 static void __exit belkin_sa_exit (void)
 599 {
 600         usb_deregister (&belkin_driver);
 601         usb_serial_deregister (&belkin_device);
 602 }
 603
 604
 605 module_init (belkin_sa_init);
 606 module_exit (belkin_sa_exit);
 607
 608 MODULE_AUTHOR( DRIVER_AUTHOR );
 609 MODULE_DESCRIPTION( DRIVER_DESC );
 610 MODULE_VERSION( DRIVER_VERSION );
 611 MODULE_LICENSE("GPL");
 612
 613 module_param(debug, bool, S_IRUGO | S_IWUSR);
 614 MODULE_PARM_DESC(debug, "Debug enabled or not");