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_driver belkin_device = {
 125         .driver = {
 126                 .owner =        THIS_MODULE,
 127                 .name =         "belkin",
 128         },
 129         .description =          "Belkin / Peracom / GoHubs USB Serial Adapter",
 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, struct pt_regs *regs)
 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         unsigned long flags;
 259
 260         switch (urb->status) {
 261         case 0:
 262                 /* success */
 263                 break;
 264         case -ECONNRESET:
 265         case -ENOENT:
 266         case -ESHUTDOWN:
 267                 /* this urb is terminated, clean up */
 268                 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
 269                 return;
 270         default:
 271                 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
 272                 goto exit;
 273         }
 274
 275         usb_serial_debug_data(debug, &port->dev, __FUNCTION__, urb->actual_length, data);
 276
 277         /* Handle known interrupt data */
 278         /* ignore data[0] and data[1] */
 279
 280         priv = usb_get_serial_port_data(port);
 281         spin_lock_irqsave(&priv->lock, flags);
 282         priv->last_msr = data[BELKIN_SA_MSR_INDEX];
 283
 284         /* Record Control Line states */
 285         if (priv->last_msr & BELKIN_SA_MSR_DSR)
 286                 priv->control_state |= TIOCM_DSR;
 287         else
 288                 priv->control_state &= ~TIOCM_DSR;
 289
 290         if (priv->last_msr & BELKIN_SA_MSR_CTS)
 291                 priv->control_state |= TIOCM_CTS;
 292         else
 293                 priv->control_state &= ~TIOCM_CTS;
 294
 295         if (priv->last_msr & BELKIN_SA_MSR_RI)
 296                 priv->control_state |= TIOCM_RI;
 297         else
 298                 priv->control_state &= ~TIOCM_RI;
 299
 300         if (priv->last_msr & BELKIN_SA_MSR_CD)
 301                 priv->control_state |= TIOCM_CD;
 302         else
 303                 priv->control_state &= ~TIOCM_CD;
 304
 305         /* Now to report any errors */
 306         priv->last_lsr = data[BELKIN_SA_LSR_INDEX];
 307 #if 0
 308         /*
 309          * fill in the flip buffer here, but I do not know the relation
 310          * to the current/next receive buffer or characters.  I need
 311          * to look in to this before committing any code.
 312          */
 313         if (priv->last_lsr & BELKIN_SA_LSR_ERR) {
 314                 tty = port->tty;
 315                 /* Overrun Error */
 316                 if (priv->last_lsr & BELKIN_SA_LSR_OE) {
 317                 }
 318                 /* Parity Error */
 319                 if (priv->last_lsr & BELKIN_SA_LSR_PE) {
 320                 }
 321                 /* Framing Error */
 322                 if (priv->last_lsr & BELKIN_SA_LSR_FE) {
 323                 }
 324                 /* Break Indicator */
 325                 if (priv->last_lsr & BELKIN_SA_LSR_BI) {
 326                 }
 327         }
 328 #endif
 329         spin_unlock_irqrestore(&priv->lock, flags);
 330 exit:
 331         retval = usb_submit_urb (urb, GFP_ATOMIC);
 332         if (retval)
 333                 err ("%s - usb_submit_urb failed with result %d",
 334                      __FUNCTION__, retval);
 335 }
 336
 337 static void belkin_sa_set_termios (struct usb_serial_port *port, struct termios *old_termios)
 338 {
 339         struct usb_serial *serial = port->serial;
 340         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 341         unsigned int iflag;
 342         unsigned int cflag;
 343         unsigned int old_iflag = 0;
 344         unsigned int old_cflag = 0;
 345         __u16 urb_value = 0; /* Will hold the new flags */
 346         unsigned long flags;
 347         unsigned long control_state;
 348         int bad_flow_control;
 349
 350         if ((!port->tty) || (!port->tty->termios)) {
 351                 dbg ("%s - no tty or termios structure", __FUNCTION__);
 352                 return;
 353         }
 354
 355         iflag = port->tty->termios->c_iflag;
 356         cflag = port->tty->termios->c_cflag;
 357
 358         /* get a local copy of the current port settings */
 359         spin_lock_irqsave(&priv->lock, flags);
 360         control_state = priv->control_state;
 361         bad_flow_control = priv->bad_flow_control;
 362         spin_unlock_irqrestore(&priv->lock, flags);
 363
 364         /* check that they really want us to change something */
 365         if (old_termios) {
 366                 if ((cflag == old_termios->c_cflag) &&
 367                     (RELEVANT_IFLAG(port->tty->termios->c_iflag) == RELEVANT_IFLAG(old_termios->c_iflag))) {
 368                         dbg("%s - nothing to change...", __FUNCTION__);
 369                         return;
 370                 }
 371                 old_iflag = old_termios->c_iflag;
 372                 old_cflag = old_termios->c_cflag;
 373         }
 374
 375         /* Set the baud rate */
 376         if( (cflag&CBAUD) != (old_cflag&CBAUD) ) {
 377                 /* reassert DTR and (maybe) RTS on transition from B0 */
 378                 if( (old_cflag&CBAUD) == B0 ) {
 379                         control_state |= (TIOCM_DTR|TIOCM_RTS);
 380                         if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0)
 381                                 err("Set DTR error");
 382                         /* don't set RTS if using hardware flow control */
 383                         if (!(old_cflag&CRTSCTS) )
 384                                 if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 1) < 0)
 385                                         err("Set RTS error");
 386                 }
 387
 388                 switch(cflag & CBAUD) {
 389                         case B0: /* handled below */ break;
 390                         case B300: urb_value = BELKIN_SA_BAUD(300); break;
 391                         case B600: urb_value = BELKIN_SA_BAUD(600); break;
 392                         case B1200: urb_value = BELKIN_SA_BAUD(1200); break;
 393                         case B2400: urb_value = BELKIN_SA_BAUD(2400); break;
 394                         case B4800: urb_value = BELKIN_SA_BAUD(4800); break;
 395                         case B9600: urb_value = BELKIN_SA_BAUD(9600); break;
 396                         case B19200: urb_value = BELKIN_SA_BAUD(19200); break;
 397                         case B38400: urb_value = BELKIN_SA_BAUD(38400); break;
 398                         case B57600: urb_value = BELKIN_SA_BAUD(57600); break;
 399                         case B115200: urb_value = BELKIN_SA_BAUD(115200); break;
 400                         case B230400: urb_value = BELKIN_SA_BAUD(230400); break;
 401                         default: err("BELKIN USB Serial Adapter: unsupported baudrate request, using default of 9600");
 402                                 urb_value = BELKIN_SA_BAUD(9600); break;
 403                 }
 404                 if ((cflag & CBAUD) != B0 ) {
 405                         if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0)
 406                                 err("Set baudrate error");
 407                 } else {
 408                         /* Disable flow control */
 409                         if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, BELKIN_SA_FLOW_NONE) < 0)
 410                                 err("Disable flowcontrol error");
 411
 412                         /* Drop RTS and DTR */
 413                         control_state &= ~(TIOCM_DTR | TIOCM_RTS);
 414                         if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0)
 415                                 err("DTR LOW error");
 416                         if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0)
 417                                 err("RTS LOW error");
 418                 }
 419         }
 420
 421         /* set the parity */
 422         if( (cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD)) ) {
 423                 if (cflag & PARENB)
 424                         urb_value = (cflag & PARODD) ?  BELKIN_SA_PARITY_ODD : BELKIN_SA_PARITY_EVEN;
 425                 else
 426                         urb_value = BELKIN_SA_PARITY_NONE;
 427                 if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0)
 428                         err("Set parity error");
 429         }
 430
 431         /* set the number of data bits */
 432         if( (cflag&CSIZE) != (old_cflag&CSIZE) ) {
 433                 switch (cflag & CSIZE) {
 434                         case CS5: urb_value = BELKIN_SA_DATA_BITS(5); break;
 435                         case CS6: urb_value = BELKIN_SA_DATA_BITS(6); break;
 436                         case CS7: urb_value = BELKIN_SA_DATA_BITS(7); break;
 437                         case CS8: urb_value = BELKIN_SA_DATA_BITS(8); break;
 438                         default: err("CSIZE was not CS5-CS8, using default of 8");
 439                                 urb_value = BELKIN_SA_DATA_BITS(8);
 440                                 break;
 441                 }
 442                 if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0)
 443                         err("Set data bits error");
 444         }
 445
 446         /* set the number of stop bits */
 447         if( (cflag&CSTOPB) != (old_cflag&CSTOPB) ) {
 448                 urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2) : BELKIN_SA_STOP_BITS(1);
 449                 if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST, urb_value) < 0)
 450                         err("Set stop bits error");
 451         }
 452
 453         /* Set flow control */
 454         if( (iflag&IXOFF)   != (old_iflag&IXOFF)
 455         ||      (iflag&IXON)    != (old_iflag&IXON)
 456         ||  (cflag&CRTSCTS) != (old_cflag&CRTSCTS) ) {
 457                 urb_value = 0;
 458                 if ((iflag & IXOFF) || (iflag & IXON))
 459                         urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
 460                 else
 461                         urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON);
 462
 463                 if (cflag & CRTSCTS)
 464                         urb_value |=  (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
 465                 else
 466                         urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS);
 467
 468                 if (bad_flow_control)
 469                         urb_value &= ~(BELKIN_SA_FLOW_IRTS);
 470
 471                 if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0)
 472                         err("Set flow control error");
 473         }
 474
 475         /* save off the modified port settings */
 476         spin_lock_irqsave(&priv->lock, flags);
 477         priv->control_state = control_state;
 478         spin_unlock_irqrestore(&priv->lock, flags);
 479 } /* belkin_sa_set_termios */
 480
 481
 482 static void belkin_sa_break_ctl( struct usb_serial_port *port, int break_state )
 483 {
 484         struct usb_serial *serial = port->serial;
 485
 486         if (BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0) < 0)
 487                 err("Set break_ctl %d", break_state);
 488 }
 489
 490
 491 static int belkin_sa_tiocmget (struct usb_serial_port *port, struct file *file)
 492 {
 493         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 494         unsigned long control_state;
 495         unsigned long flags;
 496
 497         dbg("%s", __FUNCTION__);
 498
 499         spin_lock_irqsave(&priv->lock, flags);
 500         control_state = priv->control_state;
 501         spin_unlock_irqrestore(&priv->lock, flags);
 502
 503         return control_state;
 504 }
 505
 506
 507 static int belkin_sa_tiocmset (struct usb_serial_port *port, struct file *file,
 508                                unsigned int set, unsigned int clear)
 509 {
 510         struct usb_serial *serial = port->serial;
 511         struct belkin_sa_private *priv = usb_get_serial_port_data(port);
 512         unsigned long control_state;
 513         unsigned long flags;
 514         int retval;
 515         int rts = 0;
 516         int dtr = 0;
 517
 518         dbg("%s", __FUNCTION__);
 519
 520         spin_lock_irqsave(&priv->lock, flags);
 521         control_state = priv->control_state;
 522
 523         if (set & TIOCM_RTS) {
 524                 control_state |= TIOCM_RTS;
 525                 rts = 1;
 526         }
 527         if (set & TIOCM_DTR) {
 528                 control_state |= TIOCM_DTR;
 529                 dtr = 1;
 530         }
 531         if (clear & TIOCM_RTS) {
 532                 control_state &= ~TIOCM_RTS;
 533                 rts = 0;
 534         }
 535         if (clear & TIOCM_DTR) {
 536                 control_state &= ~TIOCM_DTR;
 537                 dtr = 0;
 538         }
 539
 540         priv->control_state = control_state;
 541         spin_unlock_irqrestore(&priv->lock, flags);
 542
 543         retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts);
 544         if (retval < 0) {
 545                 err("Set RTS error %d", retval);
 546                 goto exit;
 547         }
 548
 549         retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr);
 550         if (retval < 0) {
 551                 err("Set DTR error %d", retval);
 552                 goto exit;
 553         }
 554 exit:
 555         return retval;
 556 }
 557
 558
 559 static int belkin_sa_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 560 {
 561         switch (cmd) {
 562         case TIOCMIWAIT:
 563                 /* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
 564                 /* TODO */
 565                 return( 0 );
 566
 567         case TIOCGICOUNT:
 568                 /* return count of modemline transitions */
 569                 /* TODO */
 570                 return 0;
 571
 572         default:
 573                 dbg("belkin_sa_ioctl arg not supported - 0x%04x",cmd);
 574                 return(-ENOIOCTLCMD);
 575                 break;
 576         }
 577         return 0;
 578 } /* belkin_sa_ioctl */
 579
 580
 581 static int __init belkin_sa_init (void)
 582 {
 583         int retval;
 584         retval = usb_serial_register(&belkin_device);
 585         if (retval)
 586                 goto failed_usb_serial_register;
 587         retval = usb_register(&belkin_driver);
 588         if (retval)
 589                 goto failed_usb_register;
 590         info(DRIVER_DESC " " DRIVER_VERSION);
 591         return 0;
 592 failed_usb_register:
 593         usb_serial_deregister(&belkin_device);
 594 failed_usb_serial_register:
 595         return retval;
 596 }
 597
 598
 599 static void __exit belkin_sa_exit (void)
 600 {
 601         usb_deregister (&belkin_driver);
 602         usb_serial_deregister (&belkin_device);
 603 }
 604
 605
 606 module_init (belkin_sa_init);
 607 module_exit (belkin_sa_exit);
 608
 609 MODULE_AUTHOR( DRIVER_AUTHOR );
 610 MODULE_DESCRIPTION( DRIVER_DESC );
 611 MODULE_VERSION( DRIVER_VERSION );
 612 MODULE_LICENSE("GPL");
 613
 614 module_param(debug, bool, S_IRUGO | S_IWUSR);
 615 MODULE_PARM_DESC(debug, "Debug enabled or not");