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/kernel.h>
  67 #include <linux/errno.h>
  68 #include <linux/init.h>
  69 #include <linux/slab.h>
  70 #include <linux/tty.h>
  71 #include <linux/tty_driver.h>
  72 #include <linux/tty_flip.h>
  73 #include <linux/module.h>
  74 #include <linux/spinlock.h>
  75 #include <asm/uaccess.h>
  76 #include <linux/usb.h>
  77 #include <linux/usb/serial.h>
  78 #include "belkin_sa.h"
  79
  80 static int debug;
  81
  82 /*
  83  * Version Information
  84  */
  85 #define DRIVER_VERSION "v1.2"
  86 #define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>"
  87 #define DRIVER_DESC "USB Belkin Serial converter driver"
  88
  89 /* function prototypes for a Belkin USB Serial Adapter F5U103 */
  90 static int  belkin_sa_startup           (struct usb_serial *serial);
  91 static void belkin_sa_shutdown          (struct usb_serial *serial);
  92 static int  belkin_sa_open              (struct usb_serial_port *port, struct file *filp);
  93 static void belkin_sa_close             (struct usb_serial_port *port, struct file *filp);
  94 static void belkin_sa_read_int_callback (struct urb *urb);
  95 static void belkin_sa_set_termios       (struct usb_serial_port *port, struct ktermios * old);
  96 static int  belkin_sa_ioctl             (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
  97 static void belkin_sa_break_ctl         (struct usb_serial_port *port, int break_state );
  98 static int  belkin_sa_tiocmget          (struct usb_serial_port *port, struct file *file);
  99 static int  belkin_sa_tiocmset          (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear);
 100
 101
 102 static struct usb_device_id id_table_combined [] = {
 103         { USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) },
 104         { USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) },
 105         { USB_DEVICE(PERACOM_VID, PERACOM_PID) },
 106         { USB_DEVICE(GOHUBS_VID, GOHUBS_PID) },
 107         { USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) },
 108         { USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) },
 109         { }                                                     /* Terminating entry */
 110 };
 111
 112 MODULE_DEVICE_TABLE (usb, id_table_combined);
 113
 114 static struct usb_driver belkin_driver = {
 115         .name =         "belkin",
 116         .probe =        usb_serial_probe,
 117         .disconnect =   usb_serial_disconnect,
 118         .id_table =     id_table_combined,
 119         .no_dynamic_id =        1,
 120 };
 121
 122 /* All of the device info needed for the serial converters */
 123 static struct usb_serial_driver belkin_device = {
 124         .driver = {
 125                 .owner =        THIS_MODULE,
 126                 .name =         "belkin",
 127         },
 128         .description =          "Belkin / Peracom / GoHubs USB Serial Adapter",
 129         .usb_driver =           &belkin_driver,
 130         .id_table =             id_table_combined,
 131         .num_interrupt_in =     1,
 132         .num_bulk_in =          1,
 133         .num_bulk_out =         1,
 134         .num_ports =            1,
 135         .open =                 belkin_sa_open,
 136         .close =                belkin_sa_close,
 137         .read_int_callback =    belkin_sa_read_int_callback,    /* How we get the status info */
 138         .ioctl =                belkin_sa_ioctl,
 139         .set_termios =          belkin_sa_set_termios,
 140         .break_ctl =            belkin_sa_break_ctl,
 141         .tiocmget =             belkin_sa_tiocmget,
 142         .tiocmset =             belkin_sa_tiocmset,
 143         .attach =               belkin_sa_startup,
 144         .shutdown =             belkin_sa_shutdown,
 145 };
 146
 147
 148 struct belkin_sa_private {
 149         spinlock_t              lock;
 150         unsigned long           control_state;
 151         unsigned char           last_lsr;
 152         unsigned char           last_msr;
 153         int                     bad_flow_control;
 154 };
 155
 156
 157 /*
 158  * ***************************************************************************
 159  * Belkin USB Serial Adapter F5U103 specific driver functions
 160  * ***************************************************************************
 161  */
 162
 163 #define WDR_TIMEOUT 5000 /* default urb timeout */
 164
 165 /* assumes that struct usb_serial *serial is available */
 166 #define BSA_USB_CMD(c,v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \
 167                                             (c), BELKIN_SA_SET_REQUEST_TYPE, \
 168                                             (v), 0, NULL, 0, WDR_TIMEOUT)
 169
 170 /* do some startup allocations not currently performed by usb_serial_probe() */
 171 static int belkin_sa_startup (struct usb_serial *serial)
 172 {
 173         struct usb_device *dev = serial->dev;
 174         struct belkin_sa_private *priv;
 175
 176         /* allocate the private data structure */
 177         priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL);
 178         if (!priv)
 179                 return (-1); /* error */
 180         /* set initial values for control structures */
 181         spin_lock_init(&priv->lock);
 182         priv->control_state = 0;
 183         priv->last_lsr = 0;
 184         priv->last_msr = 0;
 185         /* see comments at top of file */
 186         priv->bad_flow_control = (le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0;
 187         info("bcdDevice: %04x, bfc: %d", le16_to_cpu(dev->descriptor.bcdDevice), priv->bad_flow_control);
 188
 189         init_waitqueue_head(&serial->port[0]->write_wait);
 190         usb_set_serial_port_data(serial->port[0], priv);
 191
 192         return (0);
 193 }
 194
 195
 196 static void belkin_sa_shutdown (struct usb_serial *serial)
 197 {
 198         struct belkin_sa_private *priv;
 199         int i;
 200
 201         dbg ("%s", __FUNCTION__);
 202
 203         /* stop reads and writes on all ports */
 204         for (i=0; i < serial->num_ports; ++i) {
 205                 /* My special items, the standard routines free my urbs */
 206                 priv = usb_get_serial_port_data(serial->port[i]);
 207                 kfree(priv);
 208         }
 209 }
 210
 211
 212 static int  belkin_sa_open (struct usb_serial_port *port, struct file *filp)
 213 {
 214         int retval = 0;
 215
 216         dbg("%s port %d", __FUNCTION__, port->number);
 217
 218         /*Start reading from the device*/
 219         /* TODO: Look at possibility of submitting multiple URBs to device to
 220          *       enhance buffering.  Win trace shows 16 initial read URBs.
 221          */
 222         port->read_urb->dev = port->serial->dev;
 223         retval = usb_submit_urb(port->read_urb, GFP_KERNEL);
 224         if (retval) {
 225                 err("usb_submit_urb(read bulk) failed");
 226                 goto exit;
 227         }
 228
 229         port->interrupt_in_urb->dev = port->serial->dev;
 230         retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 231         if (retval) {
 232                 usb_kill_urb(port->read_urb);
 233                 err(" usb_submit_urb(read int) failed");
 234         }
 235
 236 exit:
 237         return retval;
 238 } /* belkin_sa_open */
 239
 240
 241 static void belkin_sa_close (struct usb_serial_port *port, struct file *filp)
 242 {
 243         dbg("%s port %d", __FUNCTION__, port->number);
 244
 245         /* shutdown our bulk reads and writes */
 246         usb_kill_urb(port->write_urb);
 247         usb_kill_urb(port->read_urb);
 248         usb_kill_urb(port->interrupt_in_urb);
 249 } /* belkin_sa_close */
 250
 251
 252 static void belkin_sa_read_int_callback (struct urb *urb)
 253 {
 254         struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
 255         struct belkin_sa_private *priv;
 256         unsigned char *data = urb->transfer_buffer;
 257         int retval;
 258         int status = urb->status;
 259         unsigned long flags;
 260
 261         switch (status) {
 262         case 0:
 263                 /* success */
 264                 break;
 265         case -ECONNRESET:
 266         case -ENOENT:
 267         case -ESHUTDOWN:
 268                 /* this urb is terminated, clean up */
 269                 dbg("%s - urb shutting down with status: %d",
 270                     __FUNCTION__, status);
 271                 return;
 272         default:
 273                 dbg("%s - nonzero urb status received: %d",
 274                     __FUNCTION__, status);
 275                 goto exit;
 276         }
 277
 278         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
 279
 280         /* Handle known interrupt data */
 281         /* ignore data[0] and data[1] */
 282
 283         priv = usb_get_serial_port_data(port);
 284         spin_lock_irqsave(&priv->lock, flags);
 285         priv->last_msr = data[BELKIN_SA_MSR_INDEX];
 286
 287         /* Record Control Line states */
 288         if (priv->last_msr & BELKIN_SA_MSR_DSR)
 289                 priv->control_state |= TIOCM_DSR;
 290         else
 291                 priv->control_state &= ~TIOCM_DSR;
 292
 293         if (priv->last_msr & BELKIN_SA_MSR_CTS)
 294                 priv->control_state |= TIOCM_CTS;
 295         else
 296                 priv->control_state &= ~TIOCM_CTS;
 297
 298         if (priv->last_msr & BELKIN_SA_MSR_RI)
 299                 priv->control_state |= TIOCM_RI;
 300         else
 301                 priv->control_state &= ~TIOCM_RI;
 302
 303         if (priv->last_msr & BELKIN_SA_MSR_CD)
 304                 priv->control_state |= TIOCM_CD;
 305         else
 306                 priv->control_state &= ~TIOCM_CD;
 307
 308         /* Now to report any errors */
 309         priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
 310 #if 0
 311         /*
 312          * fill in the flip buffer here, but I do not know the relation
 313          * to the current/next receive buffer or characters.  I need
 314          * to look in to this before committing any code.
 315          */
 316         if (priv->last_lsr & BELKIN_SA_LSR_ERR) {
 317                 tty = port->tty;
 318                 /* Overrun Error */
 319                 if (priv->last_lsr & BELKIN_SA_LSR_OE) {
 320                 }
 321                 /* Parity Error */
 322                 if (priv->last_lsr & BELKIN_SA_LSR_PE) {
 323                 }
 324                 /* Framing Error */
 325                 if (priv->last_lsr & BELKIN_SA_LSR_FE) {
 326                 }
 327                 /* Break Indicator */
 328                 if (priv->last_lsr & BELKIN_SA_LSR_BI) {
 329                 }
 330         }
 331 #endif
 332         spin_unlock_irqrestore(&priv->lock, flags);
 333 exit:
 334         retval = usb_submit_urb (urb, GFP_ATOMIC);
 335         if (retval)
 336                 err ("%s - usb_submit_urb failed with result %d",
 337                      __FUNCTION__, retval);
 338 }
 339
 340 static void belkin_sa_set_termios (struct usb_serial_port *port, struct ktermios *old_termios)
 341 {
 342         struct usb_serial *serial = port->serial;
 343         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 344         unsigned int iflag;
 345         unsigned int cflag;
 346         unsigned int old_iflag = 0;
 347         unsigned int old_cflag = 0;
 348         __u16 urb_value = 0; /* Will hold the new flags */
 349         unsigned long flags;
 350         unsigned long control_state;
 351         int bad_flow_control;
 352         speed_t baud;
 353
 354         if ((!port->tty) || (!port->tty->termios)) {
 355                 dbg ("%s - no tty or termios structure", __FUNCTION__);
 356                 return;
 357         }
 358
 359         iflag = port->tty->termios->c_iflag;
 360         cflag = port->tty->termios->c_cflag;
 361
 362         /* get a local copy of the current port settings */
 363         spin_lock_irqsave(&priv->lock, flags);
 364         control_state = priv->control_state;
 365         bad_flow_control = priv->bad_flow_control;
 366         spin_unlock_irqrestore(&priv->lock, flags);
 367
 368         old_iflag = old_termios->c_iflag;
 369         old_cflag = old_termios->c_cflag;
 370
 371         /* Set the baud rate */
 372         if( (cflag&CBAUD) != (old_cflag&CBAUD) ) {
 373                 /* reassert DTR and (maybe) RTS on transition from B0 */
 374                 if( (old_cflag&CBAUD) == B0 ) {
 375                         control_state |= (TIOCM_DTR|TIOCM_RTS);
 376                         if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
 377                                 err("Set DTR error");
 378                         /* don't set RTS if using hardware flow control */
 379                         if (!(old_cflag&CRTSCTS) )
 380                                 if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 1) < 0)
 381                                         err("Set RTS error");
 382                 }
 383         }
 384
 385         baud = tty_get_baud_rate(port->tty);
 386         urb_value = BELKIN_SA_BAUD(baud);
 387         /* Clip to maximum speed */
 388         if (urb_value == 0)
 389                 urb_value = 1;
 390         /* Turn it back into a resulting real baud rate */
 391         baud = BELKIN_SA_BAUD(urb_value);
 392         /* FIXME: Once the tty updates are done then push this back to the tty */
 393
 394         if ((cflag & CBAUD) != B0 ) {
 395                 if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
 396                         err("Set baudrate error");
 397         } else {
 398                 /* Disable flow control */
 399                 if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, BELKIN_SA_FLOW_NONE) < 0)
 400                         err("Disable flowcontrol error");
 401                 /* Drop RTS and DTR */
 402                 control_state &= ~(TIOCM_DTR | TIOCM_RTS);
 403                 if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
 404                         err("DTR LOW error");
 405                 if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
 406                         err("RTS LOW error");
 407         }
 408
 409         /* set the parity */
 410         if( (cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD)) ) {
 411                 if (cflag & PARENB)
 412                         urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD : BELKIN_SA_PARITY_EVEN;
 413                 else
 414                         urb_value = BELKIN_SA_PARITY_NONE;
 415                 if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
 416                         err("Set parity error");
 417         }
 418
 419         /* set the number of data bits */
 420         if( (cflag&CSIZE) != (old_cflag&CSIZE) ) {
 421                 switch (cflag & CSIZE) {
 422                         case CS5: urb_value = BELKIN_SA_DATA_BITS(5); break;
 423                         case CS6: urb_value = BELKIN_SA_DATA_BITS(6); break;
 424                         case CS7: urb_value = BELKIN_SA_DATA_BITS(7); break;
 425                         case CS8: urb_value = BELKIN_SA_DATA_BITS(8); break;
 426                         default: dbg("CSIZE was not CS5-CS8, using default of 8");
 427                                 urb_value = BELKIN_SA_DATA_BITS(8);
 428                                 break;
 429                 }
 430                 if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
 431                         err("Set data bits error");
 432         }
 433
 434         /* set the number of stop bits */
 435         if( (cflag&CSTOPB) != (old_cflag&CSTOPB) ) {
 436                 urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2) : BELKIN_SA_STOP_BITS(1);
 437                 if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST, urb_value) < 0)
 438                         err("Set stop bits error");
 439         }
 440
 441         /* Set flow control */
 442         if( (iflag&IXOFF)   != (old_iflag&IXOFF)
 443         ||      (iflag&IXON)    != (old_iflag&IXON)
 444         ||  (cflag&CRTSCTS) != (old_cflag&CRTSCTS) ) {
 445                 urb_value = 0;
 446                 if ((iflag & IXOFF) || (iflag & IXON))
 447                         urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
 448                 else
 449                         urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
 450
 451                 if (cflag & CRTSCTS)
 452                         urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
 453                 else
 454                         urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
 455
 456                 if (bad_flow_control)
 457                         urb_value &= ~(BELKIN_SA_FLOW_IRTS);
 458
 459                 if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
 460                         err("Set flow control error");
 461         }
 462
 463         /* save off the modified port settings */
 464         spin_lock_irqsave(&priv->lock, flags);
 465         priv->control_state = control_state;
 466         spin_unlock_irqrestore(&priv->lock, flags);
 467 } /* belkin_sa_set_termios */
 468
 469
 470 static void belkin_sa_break_ctl( struct usb_serial_port *port, int break_state )
 471 {
 472         struct usb_serial *serial = port->serial;
 473
 474         if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
 475                 err("Set break_ctl %d", break_state);
 476 }
 477
 478
 479 static int belkin_sa_tiocmget (struct usb_serial_port *port, struct file *file)
 480 {
 481         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 482         unsigned long control_state;
 483         unsigned long flags;
 484
 485         dbg("%s", __FUNCTION__);
 486
 487         spin_lock_irqsave(&priv->lock, flags);
 488         control_state = priv->control_state;
 489         spin_unlock_irqrestore(&priv->lock, flags);
 490
 491         return control_state;
 492 }
 493
 494
 495 static int belkin_sa_tiocmset (struct usb_serial_port *port, struct file *file,
 496                                unsigned int set, unsigned int clear)
 497 {
 498         struct usb_serial *serial = port->serial;
 499         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 500         unsigned long control_state;
 501         unsigned long flags;
 502         int retval;
 503         int rts = 0;
 504         int dtr = 0;
 505
 506         dbg("%s", __FUNCTION__);
 507
 508         spin_lock_irqsave(&priv->lock, flags);
 509         control_state = priv->control_state;
 510
 511         if (set & TIOCM_RTS) {
 512                 control_state |= TIOCM_RTS;
 513                 rts = 1;
 514         }
 515         if (set & TIOCM_DTR) {
 516                 control_state |= TIOCM_DTR;
 517                 dtr = 1;
 518         }
 519         if (clear & TIOCM_RTS) {
 520                 control_state &= ~TIOCM_RTS;
 521                 rts = 0;
 522         }
 523         if (clear & TIOCM_DTR) {
 524                 control_state &= ~TIOCM_DTR;
 525                 dtr = 0;
 526         }
 527
 528         priv->control_state = control_state;
 529         spin_unlock_irqrestore(&priv->lock, flags);
 530
 531         retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
 532         if (retval < 0) {
 533                 err("Set RTS error %d", retval);
 534                 goto exit;
 535         }
 536
 537         retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
 538         if (retval < 0) {
 539                 err("Set DTR error %d", retval);
 540                 goto exit;
 541         }
 542 exit:
 543         return retval;
 544 }
 545
 546
 547 static int belkin_sa_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 548 {
 549         switch (cmd) {
 550         case TIOCMIWAIT:
 551                 /* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
 552                 /* TODO */
 553                 return( 0 );
 554
 555         case TIOCGICOUNT:
 556                 /* return count of modemline transitions */
 557                 /* TODO */
 558                 return 0;
 559
 560         default:
 561                 dbg("belkin_sa_ioctl arg not supported - 0x%04x",cmd);
 562                 return(-ENOIOCTLCMD);
 563                 break;
 564         }
 565         return 0;
 566 } /* belkin_sa_ioctl */
 567
 568
 569 static int __init belkin_sa_init (void)
 570 {
 571         int retval;
 572         retval = usb_serial_register(&belkin_device);
 573         if (retval)
 574                 goto failed_usb_serial_register;
 575         retval = usb_register(&belkin_driver);
 576         if (retval)
 577                 goto failed_usb_register;
 578         info(DRIVER_DESC " " DRIVER_VERSION);
 579         return 0;
 580 failed_usb_register:
 581         usb_serial_deregister(&belkin_device);
 582 failed_usb_serial_register:
 583         return retval;
 584 }
 585
 586
 587 static void __exit belkin_sa_exit (void)
 588 {
 589         usb_deregister (&belkin_driver);
 590         usb_serial_deregister (&belkin_device);
 591 }
 592
 593
 594 module_init (belkin_sa_init);
 595 module_exit (belkin_sa_exit);
 596
 597 MODULE_AUTHOR( DRIVER_AUTHOR );
 598 MODULE_DESCRIPTION( DRIVER_DESC );
 599 MODULE_VERSION( DRIVER_VERSION );
 600 MODULE_LICENSE("GPL");
 601
 602 module_param(debug, bool, S_IRUGO | S_IWUSR);
 603 MODULE_PARM_DESC(debug, "Debug enabled or not");