drivers/usb/serial/oti6858.c

   1 /*
   2  * Ours Technology Inc. OTi-6858 USB to serial adapter driver.
   3  *
   4  * Copyleft  (C) 2007 Kees Lemmens (adapted for kernel 2.6.20)
   5  * Copyright (C) 2006 Tomasz Michal Lukaszewski (FIXME: add e-mail)
   6  * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
   7  * Copyright (C) 2003 IBM Corp.
   8  *
   9  * Many thanks to the authors of pl2303 driver: all functions in this file
  10  * are heavily based on pl2303 code, buffering code is a 1-to-1 copy.
  11  *
  12  * Warning! You use this driver on your own risk! The only official
  13  * description of this device I have is datasheet from manufacturer,
  14  * and it doesn't contain almost any information needed to write a driver.
  15  * Almost all knowlegde used while writing this driver was gathered by:
  16  *  - analyzing traffic between device and the M$ Windows 2000 driver,
  17  *  - trying different bit combinations and checking pin states
  18  *    with a voltmeter,
  19  *  - receiving malformed frames and producing buffer overflows
  20  *    to learn how errors are reported,
  21  * So, THIS CODE CAN DESTROY OTi-6858 AND ANY OTHER DEVICES, THAT ARE
  22  * CONNECTED TO IT!
  23  *
  24  * This program is free software; you can redistribute it and/or modify
  25  * it under the terms of the GNU General Public License as published by
  26  * the Free Software Foundation; either version 2 of the License.
  27  *
  28  * See Documentation/usb/usb-serial.txt for more information on using this driver
  29  *
  30  * TODO:
  31  *  - implement correct flushing for ioctls and oti6858_close()
  32  *  - check how errors (rx overflow, parity error, framing error) are reported
  33  *  - implement oti6858_break_ctl()
  34  *  - implement more ioctls
  35  *  - test/implement flow control
  36  *  - allow setting custom baud rates
  37  */
  38
  39 #include <linux/kernel.h>
  40 #include <linux/errno.h>
  41 #include <linux/init.h>
  42 #include <linux/slab.h>
  43 #include <linux/tty.h>
  44 #include <linux/tty_driver.h>
  45 #include <linux/tty_flip.h>
  46 #include <linux/serial.h>
  47 #include <linux/module.h>
  48 #include <linux/moduleparam.h>
  49 #include <linux/spinlock.h>
  50 #include <linux/usb.h>
  51 #include <linux/usb/serial.h>
  52 #include <asm/uaccess.h>
  53 #include "oti6858.h"
  54
  55 #define OTI6858_DESCRIPTION \
  56         "Ours Technology Inc. OTi-6858 USB to serial adapter driver"
  57 #define OTI6858_AUTHOR "Tomasz Michal Lukaszewski <FIXME@FIXME>"
  58 #define OTI6858_VERSION "0.1"
  59
  60 static struct usb_device_id id_table [] = {
  61         { USB_DEVICE(OTI6858_VENDOR_ID, OTI6858_PRODUCT_ID) },
  62         { }
  63 };
  64
  65 MODULE_DEVICE_TABLE(usb, id_table);
  66
  67 static struct usb_driver oti6858_driver = {
  68         .name =         "oti6858",
  69         .probe =        usb_serial_probe,
  70         .disconnect =   usb_serial_disconnect,
  71         .id_table =     id_table,
  72         .no_dynamic_id =        1,
  73 };
  74
  75 static int debug;
  76
  77
  78 /* buffering code, copied from pl2303 driver */
  79 #define PL2303_BUF_SIZE         1024
  80 #define PL2303_TMP_BUF_SIZE     1024
  81
  82 struct oti6858_buf {
  83         unsigned int    buf_size;
  84         char            *buf_buf;
  85         char            *buf_get;
  86         char            *buf_put;
  87 };
  88
  89 /* requests */
  90 #define OTI6858_REQ_GET_STATUS          (USB_DIR_IN | USB_TYPE_VENDOR | 0x00)
  91 #define OTI6858_REQ_T_GET_STATUS        0x01
  92
  93 #define OTI6858_REQ_SET_LINE            (USB_DIR_OUT | USB_TYPE_VENDOR | 0x00)
  94 #define OTI6858_REQ_T_SET_LINE          0x00
  95
  96 #define OTI6858_REQ_CHECK_TXBUFF        (USB_DIR_IN | USB_TYPE_VENDOR | 0x01)
  97 #define OTI6858_REQ_T_CHECK_TXBUFF      0x00
  98
  99 /* format of the control packet */
 100 struct oti6858_control_pkt {
 101         __le16  divisor;        /* baud rate = 96000000 / (16 * divisor), LE */
 102 #define OTI6858_MAX_BAUD_RATE   3000000
 103         u8      frame_fmt;
 104 #define FMT_STOP_BITS_MASK      0xc0
 105 #define FMT_STOP_BITS_1         0x00
 106 #define FMT_STOP_BITS_2         0x40    /* 1.5 stop bits if FMT_DATA_BITS_5 */
 107 #define FMT_PARITY_MASK         0x38
 108 #define FMT_PARITY_NONE         0x00
 109 #define FMT_PARITY_ODD          0x08
 110 #define FMT_PARITY_EVEN         0x18
 111 #define FMT_PARITY_MARK         0x28
 112 #define FMT_PARITY_SPACE        0x38
 113 #define FMT_DATA_BITS_MASK      0x03
 114 #define FMT_DATA_BITS_5         0x00
 115 #define FMT_DATA_BITS_6         0x01
 116 #define FMT_DATA_BITS_7         0x02
 117 #define FMT_DATA_BITS_8         0x03
 118         u8      something;      /* always equals 0x43 */
 119         u8      control;        /* settings of flow control lines */
 120 #define CONTROL_MASK            0x0c
 121 #define CONTROL_DTR_HIGH        0x08
 122 #define CONTROL_RTS_HIGH        0x04
 123         u8      tx_status;
 124 #define TX_BUFFER_EMPTIED       0x09
 125         u8      pin_state;
 126 #define PIN_MASK                0x3f
 127 #define PIN_RTS                 0x20    /* output pin */
 128 #define PIN_CTS                 0x10    /* input pin, active low */
 129 #define PIN_DSR                 0x08    /* input pin, active low */
 130 #define PIN_DTR                 0x04    /* output pin */
 131 #define PIN_RI                  0x02    /* input pin, active low */
 132 #define PIN_DCD                 0x01    /* input pin, active low */
 133         u8      rx_bytes_avail;         /* number of bytes in rx buffer */;
 134 };
 135
 136 #define OTI6858_CTRL_PKT_SIZE   sizeof(struct oti6858_control_pkt)
 137 #define OTI6858_CTRL_EQUALS_PENDING(a, priv) \
 138         (    ((a)->divisor == (priv)->pending_setup.divisor) \
 139           && ((a)->control == (priv)->pending_setup.control) \
 140           && ((a)->frame_fmt == (priv)->pending_setup.frame_fmt) )
 141
 142 /* function prototypes */
 143 static int oti6858_open(struct tty_struct *tty,
 144                         struct usb_serial_port *port, struct file *filp);
 145 static void oti6858_close(struct tty_struct *tty,
 146                         struct usb_serial_port *port, struct file *filp);
 147 static void oti6858_set_termios(struct tty_struct *tty,
 148                         struct usb_serial_port *port, struct ktermios *old);
 149 static int oti6858_ioctl(struct tty_struct *tty, struct file *file,
 150                         unsigned int cmd, unsigned long arg);
 151 static void oti6858_read_int_callback(struct urb *urb);
 152 static void oti6858_read_bulk_callback(struct urb *urb);
 153 static void oti6858_write_bulk_callback(struct urb *urb);
 154 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 155                         const unsigned char *buf, int count);
 156 static int oti6858_write_room(struct tty_struct *tty);
 157 static int oti6858_chars_in_buffer(struct tty_struct *tty);
 158 static int oti6858_tiocmget(struct tty_struct *tty, struct file *file);
 159 static int oti6858_tiocmset(struct tty_struct *tty, struct file *file,
 160                                 unsigned int set, unsigned int clear);
 161 static int oti6858_startup(struct usb_serial *serial);
 162 static void oti6858_shutdown(struct usb_serial *serial);
 163
 164 /* functions operating on buffers */
 165 static struct oti6858_buf *oti6858_buf_alloc(unsigned int size);
 166 static void oti6858_buf_free(struct oti6858_buf *pb);
 167 static void oti6858_buf_clear(struct oti6858_buf *pb);
 168 static unsigned int oti6858_buf_data_avail(struct oti6858_buf *pb);
 169 static unsigned int oti6858_buf_space_avail(struct oti6858_buf *pb);
 170 static unsigned int oti6858_buf_put(struct oti6858_buf *pb, const char *buf,
 171                                         unsigned int count);
 172 static unsigned int oti6858_buf_get(struct oti6858_buf *pb, char *buf,
 173                                         unsigned int count);
 174
 175
 176 /* device info */
 177 static struct usb_serial_driver oti6858_device = {
 178         .driver = {
 179                 .owner =        THIS_MODULE,
 180                 .name =         "oti6858",
 181         },
 182         .id_table =             id_table,
 183         .num_ports =            1,
 184         .open =                 oti6858_open,
 185         .close =                oti6858_close,
 186         .write =                oti6858_write,
 187         .ioctl =                oti6858_ioctl,
 188         .set_termios =          oti6858_set_termios,
 189         .tiocmget =             oti6858_tiocmget,
 190         .tiocmset =             oti6858_tiocmset,
 191         .read_bulk_callback =   oti6858_read_bulk_callback,
 192         .read_int_callback =    oti6858_read_int_callback,
 193         .write_bulk_callback =  oti6858_write_bulk_callback,
 194         .write_room =           oti6858_write_room,
 195         .chars_in_buffer =      oti6858_chars_in_buffer,
 196         .attach =               oti6858_startup,
 197         .shutdown =             oti6858_shutdown,
 198 };
 199
 200 struct oti6858_private {
 201         spinlock_t lock;
 202
 203         struct oti6858_buf *buf;
 204         struct oti6858_control_pkt status;
 205
 206         struct {
 207                 u8 read_urb_in_use;
 208                 u8 write_urb_in_use;
 209                 u8 termios_initialized;
 210         } flags;
 211         struct delayed_work delayed_write_work;
 212
 213         struct {
 214                 __le16 divisor;
 215                 u8 frame_fmt;
 216                 u8 control;
 217         } pending_setup;
 218         u8 transient;
 219         u8 setup_done;
 220         struct delayed_work delayed_setup_work;
 221
 222         wait_queue_head_t intr_wait;
 223         struct usb_serial_port *port;   /* USB port with which associated */
 224 };
 225
 226 #undef dbg
 227 /* #define dbg(format, arg...) printk(KERN_INFO "%s: " format "\n", __FILE__, ## arg) */
 228 #define dbg(format, arg...) printk(KERN_INFO "" format "\n", ## arg)
 229
 230 static void setup_line(struct work_struct *work)
 231 {
 232         struct oti6858_private *priv = container_of(work, struct oti6858_private, delayed_setup_work.work);
 233         struct usb_serial_port *port = priv->port;
 234         struct oti6858_control_pkt *new_setup;
 235         unsigned long flags;
 236         int result;
 237
 238         dbg("%s(port = %d)", __func__, port->number);
 239
 240         if ((new_setup = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL)) == NULL) {
 241                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 242                 /* we will try again */
 243                 schedule_delayed_work(&priv->delayed_setup_work, msecs_to_jiffies(2));
 244                 return;
 245         }
 246
 247         result = usb_control_msg(port->serial->dev,
 248                                 usb_rcvctrlpipe(port->serial->dev, 0),
 249                                 OTI6858_REQ_T_GET_STATUS,
 250                                 OTI6858_REQ_GET_STATUS,
 251                                 0, 0,
 252                                 new_setup, OTI6858_CTRL_PKT_SIZE,
 253                                 100);
 254
 255         if (result != OTI6858_CTRL_PKT_SIZE) {
 256                 dev_err(&port->dev, "%s(): error reading status\n", __func__);
 257                 kfree(new_setup);
 258                 /* we will try again */
 259                 schedule_delayed_work(&priv->delayed_setup_work, msecs_to_jiffies(2));
 260                 return;
 261         }
 262
 263         spin_lock_irqsave(&priv->lock, flags);
 264         if (!OTI6858_CTRL_EQUALS_PENDING(new_setup, priv)) {
 265                 new_setup->divisor = priv->pending_setup.divisor;
 266                 new_setup->control = priv->pending_setup.control;
 267                 new_setup->frame_fmt = priv->pending_setup.frame_fmt;
 268
 269                 spin_unlock_irqrestore(&priv->lock, flags);
 270                 result = usb_control_msg(port->serial->dev,
 271                                         usb_sndctrlpipe(port->serial->dev, 0),
 272                                         OTI6858_REQ_T_SET_LINE,
 273                                         OTI6858_REQ_SET_LINE,
 274                                         0, 0,
 275                                         new_setup, OTI6858_CTRL_PKT_SIZE,
 276                                         100);
 277         } else {
 278                 spin_unlock_irqrestore(&priv->lock, flags);
 279                 result = 0;
 280         }
 281         kfree(new_setup);
 282
 283         spin_lock_irqsave(&priv->lock, flags);
 284         if (result != OTI6858_CTRL_PKT_SIZE)
 285                 priv->transient = 0;
 286         priv->setup_done = 1;
 287         spin_unlock_irqrestore(&priv->lock, flags);
 288
 289         dbg("%s(): submitting interrupt urb", __func__);
 290         port->interrupt_in_urb->dev = port->serial->dev;
 291         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 292         if (result != 0) {
 293                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 294                                 " with error %d\n", __func__, result);
 295         }
 296 }
 297
 298 void send_data(struct work_struct *work)
 299 {
 300         struct oti6858_private *priv = container_of(work, struct oti6858_private, delayed_write_work.work);
 301         struct usb_serial_port *port = priv->port;
 302         int count = 0, result;
 303         unsigned long flags;
 304         unsigned char allow;
 305
 306         dbg("%s(port = %d)", __func__, port->number);
 307
 308         spin_lock_irqsave(&priv->lock, flags);
 309         if (priv->flags.write_urb_in_use) {
 310                 spin_unlock_irqrestore(&priv->lock, flags);
 311                 schedule_delayed_work(&priv->delayed_write_work, msecs_to_jiffies(2));
 312                 return;
 313         }
 314         priv->flags.write_urb_in_use = 1;
 315
 316         count = oti6858_buf_data_avail(priv->buf);
 317         spin_unlock_irqrestore(&priv->lock, flags);
 318         if (count > port->bulk_out_size)
 319                 count = port->bulk_out_size;
 320
 321         if (count != 0) {
 322                 result = usb_control_msg(port->serial->dev,
 323                                 usb_rcvctrlpipe(port->serial->dev, 0),
 324                                 OTI6858_REQ_T_CHECK_TXBUFF,
 325                                 OTI6858_REQ_CHECK_TXBUFF,
 326                                 count, 0, &allow, 1, 100);
 327                 if (result != 1 || allow != 0)
 328                         count = 0;
 329         }
 330
 331         if (count == 0) {
 332                 priv->flags.write_urb_in_use = 0;
 333
 334                 dbg("%s(): submitting interrupt urb", __func__);
 335                 port->interrupt_in_urb->dev = port->serial->dev;
 336                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 337                 if (result != 0) {
 338                         dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 339                                 " with error %d\n", __func__, result);
 340                 }
 341                 return;
 342         }
 343
 344         spin_lock_irqsave(&priv->lock, flags);
 345         oti6858_buf_get(priv->buf, port->write_urb->transfer_buffer, count);
 346         spin_unlock_irqrestore(&priv->lock, flags);
 347
 348         port->write_urb->transfer_buffer_length = count;
 349         port->write_urb->dev = port->serial->dev;
 350         result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 351         if (result != 0) {
 352                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 353                                " with error %d\n", __func__, result);
 354                 priv->flags.write_urb_in_use = 0;
 355         }
 356
 357         usb_serial_port_softint(port);
 358 }
 359
 360 static int oti6858_startup(struct usb_serial *serial)
 361 {
 362         struct usb_serial_port *port = serial->port[0];
 363         struct oti6858_private *priv;
 364         int i;
 365
 366         for (i = 0; i < serial->num_ports; ++i) {
 367                 priv = kzalloc(sizeof(struct oti6858_private), GFP_KERNEL);
 368                 if (!priv)
 369                         break;
 370                 priv->buf = oti6858_buf_alloc(PL2303_BUF_SIZE);
 371                 if (priv->buf == NULL) {
 372                         kfree(priv);
 373                         break;
 374                 }
 375
 376                 spin_lock_init(&priv->lock);
 377                 init_waitqueue_head(&priv->intr_wait);
 378 //              INIT_WORK(&priv->setup_work, setup_line, serial->port[i]);
 379 //              INIT_WORK(&priv->write_work, send_data, serial->port[i]);
 380                 priv->port = port;
 381                 INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 382                 INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 383
 384                 usb_set_serial_port_data(serial->port[i], priv);
 385         }
 386         if (i == serial->num_ports)
 387                 return 0;
 388
 389         for (--i; i >= 0; --i) {
 390                 priv = usb_get_serial_port_data(serial->port[i]);
 391                 oti6858_buf_free(priv->buf);
 392                 kfree(priv);
 393                 usb_set_serial_port_data(serial->port[i], NULL);
 394         }
 395         return -ENOMEM;
 396 }
 397
 398 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 399                         const unsigned char *buf, int count)
 400 {
 401         struct oti6858_private *priv = usb_get_serial_port_data(port);
 402         unsigned long flags;
 403
 404         dbg("%s(port = %d, count = %d)", __func__, port->number, count);
 405
 406         if (!count)
 407                 return count;
 408
 409         spin_lock_irqsave(&priv->lock, flags);
 410         count = oti6858_buf_put(priv->buf, buf, count);
 411         spin_unlock_irqrestore(&priv->lock, flags);
 412
 413         return count;
 414 }
 415
 416 static int oti6858_write_room(struct tty_struct *tty)
 417 {
 418         struct usb_serial_port *port = tty->driver_data;
 419         struct oti6858_private *priv = usb_get_serial_port_data(port);
 420         int room = 0;
 421         unsigned long flags;
 422
 423         dbg("%s(port = %d)", __func__, port->number);
 424
 425         spin_lock_irqsave(&priv->lock, flags);
 426         room = oti6858_buf_space_avail(priv->buf);
 427         spin_unlock_irqrestore(&priv->lock, flags);
 428
 429         return room;
 430 }
 431
 432 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 433 {
 434         struct usb_serial_port *port = tty->driver_data;
 435         struct oti6858_private *priv = usb_get_serial_port_data(port);
 436         int chars = 0;
 437         unsigned long flags;
 438
 439         dbg("%s(port = %d)", __func__, port->number);
 440
 441         spin_lock_irqsave(&priv->lock, flags);
 442         chars = oti6858_buf_data_avail(priv->buf);
 443         spin_unlock_irqrestore(&priv->lock, flags);
 444
 445         return chars;
 446 }
 447
 448 static void oti6858_set_termios(struct tty_struct *tty,
 449                 struct usb_serial_port *port, struct ktermios *old_termios)
 450 {
 451         struct oti6858_private *priv = usb_get_serial_port_data(port);
 452         unsigned long flags;
 453         unsigned int cflag;
 454         u8 frame_fmt, control;
 455         __le16 divisor;
 456         int br;
 457
 458         dbg("%s(port = %d)", __func__, port->number);
 459
 460         if (!tty) {
 461                 dbg("%s(): no tty structures", __func__);
 462                 return;
 463         }
 464
 465         spin_lock_irqsave(&priv->lock, flags);
 466         if (!priv->flags.termios_initialized) {
 467                 *(tty->termios) = tty_std_termios;
 468                 tty->termios->c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
 469                 tty->termios->c_ispeed = 38400;
 470                 tty->termios->c_ospeed = 38400;
 471                 priv->flags.termios_initialized = 1;
 472         }
 473         spin_unlock_irqrestore(&priv->lock, flags);
 474
 475         cflag = tty->termios->c_cflag;
 476
 477         spin_lock_irqsave(&priv->lock, flags);
 478         divisor = priv->pending_setup.divisor;
 479         frame_fmt = priv->pending_setup.frame_fmt;
 480         control = priv->pending_setup.control;
 481         spin_unlock_irqrestore(&priv->lock, flags);
 482
 483         frame_fmt &= ~FMT_DATA_BITS_MASK;
 484         switch (cflag & CSIZE) {
 485                 case CS5:
 486                         frame_fmt |= FMT_DATA_BITS_5;
 487                         break;
 488                 case CS6:
 489                         frame_fmt |= FMT_DATA_BITS_6;
 490                         break;
 491                 case CS7:
 492                         frame_fmt |= FMT_DATA_BITS_7;
 493                         break;
 494                 default:
 495                 case CS8:
 496                         frame_fmt |= FMT_DATA_BITS_8;
 497                         break;
 498         }
 499
 500         /* manufacturer claims that this device can work with baud rates
 501          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 502          * guarantee that any other baud rate will work (especially
 503          * the higher ones)
 504          */
 505         br = tty_get_baud_rate(tty);
 506         if (br == 0) {
 507                 divisor = 0;
 508         } else {
 509                 int real_br;
 510                 int new_divisor;
 511                 br = min(br, OTI6858_MAX_BAUD_RATE);
 512
 513                 new_divisor = (96000000 + 8 * br) / (16 * br);
 514                 real_br = 96000000 / (16 * new_divisor);
 515                 divisor = cpu_to_le16(new_divisor);
 516                 tty_encode_baud_rate(tty, real_br, real_br);
 517         }
 518
 519         frame_fmt &= ~FMT_STOP_BITS_MASK;
 520         if ((cflag & CSTOPB) != 0) {
 521                 frame_fmt |= FMT_STOP_BITS_2;
 522         } else {
 523                 frame_fmt |= FMT_STOP_BITS_1;
 524         }
 525
 526         frame_fmt &= ~FMT_PARITY_MASK;
 527         if ((cflag & PARENB) != 0) {
 528                 if ((cflag & PARODD) != 0) {
 529                         frame_fmt |= FMT_PARITY_ODD;
 530                 } else {
 531                         frame_fmt |= FMT_PARITY_EVEN;
 532                 }
 533         } else {
 534                 frame_fmt |= FMT_PARITY_NONE;
 535         }
 536
 537         control &= ~CONTROL_MASK;
 538         if ((cflag & CRTSCTS) != 0)
 539                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 540
 541         /* change control lines if we are switching to or from B0 */
 542         /* FIXME:
 543         spin_lock_irqsave(&priv->lock, flags);
 544         control = priv->line_control;
 545         if ((cflag & CBAUD) == B0)
 546                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 547         else
 548                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 549         if (control != priv->line_control) {
 550                 control = priv->line_control;
 551                 spin_unlock_irqrestore(&priv->lock, flags);
 552                 set_control_lines(serial->dev, control);
 553         } else {
 554                 spin_unlock_irqrestore(&priv->lock, flags);
 555         }
 556         */
 557
 558         spin_lock_irqsave(&priv->lock, flags);
 559         if (divisor != priv->pending_setup.divisor
 560                         || control != priv->pending_setup.control
 561                         || frame_fmt != priv->pending_setup.frame_fmt) {
 562                 priv->pending_setup.divisor = divisor;
 563                 priv->pending_setup.control = control;
 564                 priv->pending_setup.frame_fmt = frame_fmt;
 565         }
 566         spin_unlock_irqrestore(&priv->lock, flags);
 567 }
 568
 569 static int oti6858_open(struct tty_struct *tty,
 570                         struct usb_serial_port *port, struct file *filp)
 571 {
 572         struct oti6858_private *priv = usb_get_serial_port_data(port);
 573         struct ktermios tmp_termios;
 574         struct usb_serial *serial = port->serial;
 575         struct oti6858_control_pkt *buf;
 576         unsigned long flags;
 577         int result;
 578
 579         dbg("%s(port = %d)", __func__, port->number);
 580
 581         usb_clear_halt(serial->dev, port->write_urb->pipe);
 582         usb_clear_halt(serial->dev, port->read_urb->pipe);
 583
 584         if (port->port.count != 1)
 585                 return 0;
 586
 587         if ((buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL)) == NULL) {
 588                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 589                 return -ENOMEM;
 590         }
 591
 592         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 593                                 OTI6858_REQ_T_GET_STATUS,
 594                                 OTI6858_REQ_GET_STATUS,
 595                                 0, 0,
 596                                 buf, OTI6858_CTRL_PKT_SIZE,
 597                                 100);
 598         if (result != OTI6858_CTRL_PKT_SIZE) {
 599                 /* assume default (after power-on reset) values */
 600                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 601                 buf->frame_fmt = 0x03;  /* 8N1 */
 602                 buf->something = 0x43;
 603                 buf->control = 0x4c;    /* DTR, RTS */
 604                 buf->tx_status = 0x00;
 605                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 606                 buf->rx_bytes_avail = 0x00;
 607         }
 608
 609         spin_lock_irqsave(&priv->lock, flags);
 610         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 611         priv->pending_setup.divisor = buf->divisor;
 612         priv->pending_setup.frame_fmt = buf->frame_fmt;
 613         priv->pending_setup.control = buf->control;
 614         spin_unlock_irqrestore(&priv->lock, flags);
 615         kfree(buf);
 616
 617         dbg("%s(): submitting interrupt urb", __func__);
 618         port->interrupt_in_urb->dev = serial->dev;
 619         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 620         if (result != 0) {
 621                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 622                                " with error %d\n", __func__, result);
 623                 oti6858_close(tty, port, NULL);
 624                 return -EPROTO;
 625         }
 626
 627         /* setup termios */
 628         if (tty)
 629                 oti6858_set_termios(tty, port, &tmp_termios);
 630
 631         return 0;
 632 }
 633
 634 static void oti6858_close(struct tty_struct *tty,
 635                         struct usb_serial_port *port, struct file *filp)
 636 {
 637         struct oti6858_private *priv = usb_get_serial_port_data(port);
 638         unsigned long flags;
 639         long timeout;
 640         wait_queue_t wait;
 641
 642         dbg("%s(port = %d)", __func__, port->number);
 643
 644         /* wait for data to drain from the buffer */
 645         spin_lock_irqsave(&priv->lock, flags);
 646         timeout = 30 * HZ;      /* PL2303_CLOSING_WAIT */
 647         init_waitqueue_entry(&wait, current);
 648         add_wait_queue(&tty->write_wait, &wait);
 649         dbg("%s(): entering wait loop", __func__);
 650         for (;;) {
 651                 set_current_state(TASK_INTERRUPTIBLE);
 652                 if (oti6858_buf_data_avail(priv->buf) == 0
 653                 || timeout == 0 || signal_pending(current)
 654                 || port->serial->disconnected)
 655                         break;
 656                 spin_unlock_irqrestore(&priv->lock, flags);
 657                 timeout = schedule_timeout(timeout);
 658                 spin_lock_irqsave(&priv->lock, flags);
 659         }
 660         set_current_state(TASK_RUNNING);
 661         remove_wait_queue(&tty->write_wait, &wait);
 662         dbg("%s(): after wait loop", __func__);
 663
 664         /* clear out any remaining data in the buffer */
 665         oti6858_buf_clear(priv->buf);
 666         spin_unlock_irqrestore(&priv->lock, flags);
 667
 668         /* wait for characters to drain from the device */
 669         /* (this is long enough for the entire 256 byte */
 670         /* pl2303 hardware buffer to drain with no flow */
 671         /* control for data rates of 1200 bps or more, */
 672         /* for lower rates we should really know how much */
 673         /* data is in the buffer to compute a delay */
 674         /* that is not unnecessarily long) */
 675         /* FIXME
 676         bps = tty_get_baud_rate(tty);
 677         if (bps > 1200)
 678                 timeout = max((HZ*2560)/bps,HZ/10);
 679         else
 680         */
 681                 timeout = 2*HZ;
 682         schedule_timeout_interruptible(timeout);
 683         dbg("%s(): after schedule_timeout_interruptible()", __func__);
 684
 685         /* cancel scheduled setup */
 686         cancel_delayed_work(&priv->delayed_setup_work);
 687         cancel_delayed_work(&priv->delayed_write_work);
 688         flush_scheduled_work();
 689
 690         /* shutdown our urbs */
 691         dbg("%s(): shutting down urbs", __func__);
 692         usb_kill_urb(port->write_urb);
 693         usb_kill_urb(port->read_urb);
 694         usb_kill_urb(port->interrupt_in_urb);
 695
 696         /*
 697         if (tty && (tty->termios->c_cflag) & HUPCL) {
 698                 // drop DTR and RTS
 699                 spin_lock_irqsave(&priv->lock, flags);
 700                 priv->pending_setup.control &= ~CONTROL_MASK;
 701                 spin_unlock_irqrestore(&priv->lock, flags);
 702         }
 703         */
 704 }
 705
 706 static int oti6858_tiocmset(struct tty_struct *tty, struct file *file,
 707                                 unsigned int set, unsigned int clear)
 708 {
 709         struct usb_serial_port *port = tty->driver_data;
 710         struct oti6858_private *priv = usb_get_serial_port_data(port);
 711         unsigned long flags;
 712         u8 control;
 713
 714         dbg("%s(port = %d, set = 0x%08x, clear = 0x%08x)",
 715                                 __func__, port->number, set, clear);
 716
 717         if (!usb_get_intfdata(port->serial->interface))
 718                 return -ENODEV;
 719
 720         /* FIXME: check if this is correct (active high/low) */
 721         spin_lock_irqsave(&priv->lock, flags);
 722         control = priv->pending_setup.control;
 723         if ((set & TIOCM_RTS) != 0)
 724                 control |= CONTROL_RTS_HIGH;
 725         if ((set & TIOCM_DTR) != 0)
 726                 control |= CONTROL_DTR_HIGH;
 727         if ((clear & TIOCM_RTS) != 0)
 728                 control &= ~CONTROL_RTS_HIGH;
 729         if ((clear & TIOCM_DTR) != 0)
 730                 control &= ~CONTROL_DTR_HIGH;
 731
 732         if (control != priv->pending_setup.control) {
 733                 priv->pending_setup.control = control;
 734         }
 735         spin_unlock_irqrestore(&priv->lock, flags);
 736
 737         return 0;
 738 }
 739
 740 static int oti6858_tiocmget(struct tty_struct *tty, struct file *file)
 741 {
 742         struct usb_serial_port *port = tty->driver_data;
 743         struct oti6858_private *priv = usb_get_serial_port_data(port);
 744         unsigned long flags;
 745         unsigned pin_state;
 746         unsigned result = 0;
 747
 748         dbg("%s(port = %d)", __func__, port->number);
 749
 750         if (!usb_get_intfdata(port->serial->interface))
 751                 return -ENODEV;
 752
 753         spin_lock_irqsave(&priv->lock, flags);
 754         pin_state = priv->status.pin_state & PIN_MASK;
 755         spin_unlock_irqrestore(&priv->lock, flags);
 756
 757         /* FIXME: check if this is correct (active high/low) */
 758         if ((pin_state & PIN_RTS) != 0)
 759                 result |= TIOCM_RTS;
 760         if ((pin_state & PIN_CTS) != 0)
 761                 result |= TIOCM_CTS;
 762         if ((pin_state & PIN_DSR) != 0)
 763                 result |= TIOCM_DSR;
 764         if ((pin_state & PIN_DTR) != 0)
 765                 result |= TIOCM_DTR;
 766         if ((pin_state & PIN_RI) != 0)
 767                 result |= TIOCM_RI;
 768         if ((pin_state & PIN_DCD) != 0)
 769                 result |= TIOCM_CD;
 770
 771         dbg("%s() = 0x%08x", __func__, result);
 772
 773         return result;
 774 }
 775
 776 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 777 {
 778         struct oti6858_private *priv = usb_get_serial_port_data(port);
 779         unsigned long flags;
 780         unsigned int prev, status;
 781         unsigned int changed;
 782
 783         spin_lock_irqsave(&priv->lock, flags);
 784         prev = priv->status.pin_state;
 785         spin_unlock_irqrestore(&priv->lock, flags);
 786
 787         while (1) {
 788                 wait_event_interruptible(priv->intr_wait, priv->status.pin_state != prev);
 789                 if (signal_pending(current))
 790                         return -ERESTARTSYS;
 791
 792                 spin_lock_irqsave(&priv->lock, flags);
 793                 status = priv->status.pin_state & PIN_MASK;
 794                 spin_unlock_irqrestore(&priv->lock, flags);
 795
 796                 changed = prev ^ status;
 797                 /* FIXME: check if this is correct (active high/low) */
 798                 if (    ((arg & TIOCM_RNG) && (changed & PIN_RI)) ||
 799                         ((arg & TIOCM_DSR) && (changed & PIN_DSR)) ||
 800                         ((arg & TIOCM_CD)  && (changed & PIN_DCD)) ||
 801                         ((arg & TIOCM_CTS) && (changed & PIN_CTS))) {
 802                                 return 0;
 803                 }
 804                 prev = status;
 805         }
 806
 807         /* NOTREACHED */
 808         return 0;
 809 }
 810
 811 static int oti6858_ioctl(struct tty_struct *tty, struct file *file,
 812                         unsigned int cmd, unsigned long arg)
 813 {
 814         struct usb_serial_port *port = tty->driver_data;
 815
 816         dbg("%s(port = %d, cmd = 0x%04x, arg = 0x%08lx)",
 817                                 __func__, port->number, cmd, arg);
 818
 819         switch (cmd) {
 820                 case TIOCMIWAIT:
 821                         dbg("%s(): TIOCMIWAIT", __func__);
 822                         return wait_modem_info(port, arg);
 823
 824                 default:
 825                         dbg("%s(): 0x%04x not supported", __func__, cmd);
 826                         break;
 827         }
 828
 829         return -ENOIOCTLCMD;
 830 }
 831
 832
 833 static void oti6858_shutdown(struct usb_serial *serial)
 834 {
 835         struct oti6858_private *priv;
 836         int i;
 837
 838         dbg("%s()", __func__);
 839
 840         for (i = 0; i < serial->num_ports; ++i) {
 841                 priv = usb_get_serial_port_data(serial->port[i]);
 842                 if (priv) {
 843                         oti6858_buf_free(priv->buf);
 844                         kfree(priv);
 845                         usb_set_serial_port_data(serial->port[i], NULL);
 846                 }
 847         }
 848 }
 849
 850 static void oti6858_read_int_callback(struct urb *urb)
 851 {
 852         struct usb_serial_port *port =  urb->context;
 853         struct oti6858_private *priv = usb_get_serial_port_data(port);
 854         int transient = 0, can_recv = 0, resubmit = 1;
 855         int status = urb->status;
 856
 857         dbg("%s(port = %d, status = %d)",
 858                                 __func__, port->number, status);
 859
 860         switch (status) {
 861         case 0:
 862                 /* success */
 863                 break;
 864         case -ECONNRESET:
 865         case -ENOENT:
 866         case -ESHUTDOWN:
 867                 /* this urb is terminated, clean up */
 868                 dbg("%s(): urb shutting down with status: %d",
 869                                         __func__, status);
 870                 return;
 871         default:
 872                 dbg("%s(): nonzero urb status received: %d",
 873                                         __func__, status);
 874                 break;
 875         }
 876
 877         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 878                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 879                 unsigned long flags;
 880
 881                 spin_lock_irqsave(&priv->lock, flags);
 882
 883                 if (!priv->transient) {
 884                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 885                                 if (xs->rx_bytes_avail == 0) {
 886                                         priv->transient = 4;
 887                                         priv->setup_done = 0;
 888                                         resubmit = 0;
 889                                         dbg("%s(): scheduling setup_line()",
 890                                             __func__);
 891                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 892                                 }
 893                         }
 894                 } else {
 895                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 896                                 priv->transient = 0;
 897                         } else if (!priv->setup_done) {
 898                                 resubmit = 0;
 899                         } else if (--priv->transient == 0) {
 900                                 if (xs->rx_bytes_avail == 0) {
 901                                         priv->transient = 4;
 902                                         priv->setup_done = 0;
 903                                         resubmit = 0;
 904                                         dbg("%s(): scheduling setup_line()",
 905                                             __func__);
 906                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 907                                 }
 908                         }
 909                 }
 910
 911                 if (!priv->transient) {
 912                         if (xs->pin_state != priv->status.pin_state)
 913                                 wake_up_interruptible(&priv->intr_wait);
 914                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 915                 }
 916
 917                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 918                         can_recv = xs->rx_bytes_avail;
 919                         priv->flags.read_urb_in_use = 1;
 920                 }
 921
 922                 transient = priv->transient;
 923                 spin_unlock_irqrestore(&priv->lock, flags);
 924         }
 925
 926         if (can_recv) {
 927                 int result;
 928
 929                 port->read_urb->dev = port->serial->dev;
 930                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 931                 if (result != 0) {
 932                         priv->flags.read_urb_in_use = 0;
 933                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 934                                         " error %d\n", __func__, result);
 935                 } else {
 936                         resubmit = 0;
 937                 }
 938         } else if (!transient) {
 939                 unsigned long flags;
 940
 941                 spin_lock_irqsave(&priv->lock, flags);
 942                 if (priv->flags.write_urb_in_use == 0
 943                                 && oti6858_buf_data_avail(priv->buf) != 0) {
 944                         schedule_delayed_work(&priv->delayed_write_work,0);
 945                         resubmit = 0;
 946                 }
 947                 spin_unlock_irqrestore(&priv->lock, flags);
 948         }
 949
 950         if (resubmit) {
 951                 int result;
 952
 953 //              dbg("%s(): submitting interrupt urb", __func__);
 954                 urb->dev = port->serial->dev;
 955                 result = usb_submit_urb(urb, GFP_ATOMIC);
 956                 if (result != 0) {
 957                         dev_err(&urb->dev->dev,
 958                                         "%s(): usb_submit_urb() failed with"
 959                                         " error %d\n", __func__, result);
 960                 }
 961         }
 962 }
 963
 964 static void oti6858_read_bulk_callback(struct urb *urb)
 965 {
 966         struct usb_serial_port *port =  urb->context;
 967         struct oti6858_private *priv = usb_get_serial_port_data(port);
 968         struct tty_struct *tty;
 969         unsigned char *data = urb->transfer_buffer;
 970         unsigned long flags;
 971         int status = urb->status;
 972         int result;
 973
 974         dbg("%s(port = %d, status = %d)",
 975                                 __func__, port->number, status);
 976
 977         spin_lock_irqsave(&priv->lock, flags);
 978         priv->flags.read_urb_in_use = 0;
 979         spin_unlock_irqrestore(&priv->lock, flags);
 980
 981         if (status != 0) {
 982                 if (!port->port.count) {
 983                         dbg("%s(): port is closed, exiting", __func__);
 984                         return;
 985                 }
 986                 /*
 987                 if (status == -EPROTO) {
 988                         // PL2303 mysteriously fails with -EPROTO reschedule the read
 989                         dbg("%s - caught -EPROTO, resubmitting the urb", __func__);
 990                         result = usb_submit_urb(urb, GFP_ATOMIC);
 991                         if (result)
 992                                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __func__, result);
 993                         return;
 994                 }
 995                 */
 996                 dbg("%s(): unable to handle the error, exiting", __func__);
 997                 return;
 998         }
 999
1000         tty = port->port.tty;
1001         if (tty != NULL && urb->actual_length > 0) {
1002                 tty_insert_flip_string(tty, data, urb->actual_length);
1003                 tty_flip_buffer_push(tty);
1004         }
1005
1006         // schedule the interrupt urb if we are still open */
1007         if (port->port.count != 0) {
1008                 port->interrupt_in_urb->dev = port->serial->dev;
1009                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1010                 if (result != 0) {
1011                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
1012                                         " error %d\n", __func__, result);
1013                 }
1014         }
1015 }
1016
1017 static void oti6858_write_bulk_callback(struct urb *urb)
1018 {
1019         struct usb_serial_port *port =  urb->context;
1020         struct oti6858_private *priv = usb_get_serial_port_data(port);
1021         int status = urb->status;
1022         int result;
1023
1024         dbg("%s(port = %d, status = %d)",
1025                                 __func__, port->number, status);
1026
1027         switch (status) {
1028         case 0:
1029                 /* success */
1030                 break;
1031         case -ECONNRESET:
1032         case -ENOENT:
1033         case -ESHUTDOWN:
1034                 /* this urb is terminated, clean up */
1035                 dbg("%s(): urb shutting down with status: %d",
1036                                         __func__, status);
1037                 priv->flags.write_urb_in_use = 0;
1038                 return;
1039         default:
1040                 /* error in the urb, so we have to resubmit it */
1041                 dbg("%s(): nonzero write bulk status received: %d",
1042                                         __func__, status);
1043                 dbg("%s(): overflow in write", __func__);
1044
1045                 port->write_urb->transfer_buffer_length = 1;
1046                 port->write_urb->dev = port->serial->dev;
1047                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1048                 if (result) {
1049                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
1050                                         " error %d\n", __func__, result);
1051                 } else {
1052                         return;
1053                 }
1054         }
1055
1056         priv->flags.write_urb_in_use = 0;
1057
1058         // schedule the interrupt urb if we are still open */
1059         port->interrupt_in_urb->dev = port->serial->dev;
1060         dbg("%s(): submitting interrupt urb", __func__);
1061         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1062         if (result != 0) {
1063                 dev_err(&port->dev, "%s(): failed submitting int urb,"
1064                                         " error %d\n", __func__, result);
1065         }
1066 }
1067
1068
1069 /*
1070  * oti6858_buf_alloc
1071  *
1072  * Allocate a circular buffer and all associated memory.
1073  */
1074 static struct oti6858_buf *oti6858_buf_alloc(unsigned int size)
1075 {
1076         struct oti6858_buf *pb;
1077
1078         if (size == 0)
1079                 return NULL;
1080
1081         pb = kmalloc(sizeof(struct oti6858_buf), GFP_KERNEL);
1082         if (pb == NULL)
1083                 return NULL;
1084
1085         pb->buf_buf = kmalloc(size, GFP_KERNEL);
1086         if (pb->buf_buf == NULL) {
1087                 kfree(pb);
1088                 return NULL;
1089         }
1090
1091         pb->buf_size = size;
1092         pb->buf_get = pb->buf_put = pb->buf_buf;
1093
1094         return pb;
1095 }
1096
1097 /*
1098  * oti6858_buf_free
1099  *
1100  * Free the buffer and all associated memory.
1101  */
1102 static void oti6858_buf_free(struct oti6858_buf *pb)
1103 {
1104         if (pb) {
1105                 kfree(pb->buf_buf);
1106                 kfree(pb);
1107         }
1108 }
1109
1110 /*
1111  * oti6858_buf_clear
1112  *
1113  * Clear out all data in the circular buffer.
1114  */
1115 static void oti6858_buf_clear(struct oti6858_buf *pb)
1116 {
1117         if (pb != NULL) {
1118                 /* equivalent to a get of all data available */
1119                 pb->buf_get = pb->buf_put;
1120         }
1121 }
1122
1123 /*
1124  * oti6858_buf_data_avail
1125  *
1126  * Return the number of bytes of data available in the circular
1127  * buffer.
1128  */
1129 static unsigned int oti6858_buf_data_avail(struct oti6858_buf *pb)
1130 {
1131         if (pb == NULL)
1132                 return 0;
1133         return ((pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size);
1134 }
1135
1136 /*
1137  * oti6858_buf_space_avail
1138  *
1139  * Return the number of bytes of space available in the circular
1140  * buffer.
1141  */
1142 static unsigned int oti6858_buf_space_avail(struct oti6858_buf *pb)
1143 {
1144         if (pb == NULL)
1145                 return 0;
1146         return ((pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size);
1147 }
1148
1149 /*
1150  * oti6858_buf_put
1151  *
1152  * Copy data data from a user buffer and put it into the circular buffer.
1153  * Restrict to the amount of space available.
1154  *
1155  * Return the number of bytes copied.
1156  */
1157 static unsigned int oti6858_buf_put(struct oti6858_buf *pb, const char *buf,
1158                                         unsigned int count)
1159 {
1160         unsigned int len;
1161
1162         if (pb == NULL)
1163                 return 0;
1164
1165         len  = oti6858_buf_space_avail(pb);
1166         if (count > len)
1167                 count = len;
1168
1169         if (count == 0)
1170                 return 0;
1171
1172         len = pb->buf_buf + pb->buf_size - pb->buf_put;
1173         if (count > len) {
1174                 memcpy(pb->buf_put, buf, len);
1175                 memcpy(pb->buf_buf, buf+len, count - len);
1176                 pb->buf_put = pb->buf_buf + count - len;
1177         } else {
1178                 memcpy(pb->buf_put, buf, count);
1179                 if (count < len)
1180                         pb->buf_put += count;
1181                 else /* count == len */
1182                         pb->buf_put = pb->buf_buf;
1183         }
1184
1185         return count;
1186 }
1187
1188 /*
1189  * oti6858_buf_get
1190  *
1191  * Get data from the circular buffer and copy to the given buffer.
1192  * Restrict to the amount of data available.
1193  *
1194  * Return the number of bytes copied.
1195  */
1196 static unsigned int oti6858_buf_get(struct oti6858_buf *pb, char *buf,
1197                                         unsigned int count)
1198 {
1199         unsigned int len;
1200
1201         if (pb == NULL)
1202                 return 0;
1203
1204         len = oti6858_buf_data_avail(pb);
1205         if (count > len)
1206                 count = len;
1207
1208         if (count == 0)
1209                 return 0;
1210
1211         len = pb->buf_buf + pb->buf_size - pb->buf_get;
1212         if (count > len) {
1213                 memcpy(buf, pb->buf_get, len);
1214                 memcpy(buf+len, pb->buf_buf, count - len);
1215                 pb->buf_get = pb->buf_buf + count - len;
1216         } else {
1217                 memcpy(buf, pb->buf_get, count);
1218                 if (count < len)
1219                         pb->buf_get += count;
1220                 else /* count == len */
1221                         pb->buf_get = pb->buf_buf;
1222         }
1223
1224         return count;
1225 }
1226
1227 /* module description and (de)initialization */
1228
1229 static int __init oti6858_init(void)
1230 {
1231         int retval;
1232
1233         if ((retval = usb_serial_register(&oti6858_device)) == 0) {
1234                 if ((retval = usb_register(&oti6858_driver)) != 0)
1235                         usb_serial_deregister(&oti6858_device);
1236                 else
1237                         return 0;
1238         }
1239
1240         return retval;
1241 }
1242
1243 static void __exit oti6858_exit(void)
1244 {
1245         usb_deregister(&oti6858_driver);
1246         usb_serial_deregister(&oti6858_device);
1247 }
1248
1249 module_init(oti6858_init);
1250 module_exit(oti6858_exit);
1251
1252 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
1253 MODULE_AUTHOR(OTI6858_AUTHOR);
1254 MODULE_VERSION(OTI6858_VERSION);
1255 MODULE_LICENSE("GPL");
1256
1257 module_param(debug, bool, S_IRUGO | S_IWUSR);
1258 MODULE_PARM_DESC(debug, "enable debug output");
1259