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
  29  * driver
  30  *
  31  * TODO:
  32  *  - implement correct flushing for ioctls and oti6858_close()
  33  *  - check how errors (rx overflow, parity error, framing error) are reported
  34  *  - implement oti6858_break_ctl()
  35  *  - implement more ioctls
  36  *  - test/implement flow control
  37  *  - allow setting custom baud rates
  38  */
  39
  40 #include <linux/kernel.h>
  41 #include <linux/errno.h>
  42 #include <linux/init.h>
  43 #include <linux/slab.h>
  44 #include <linux/tty.h>
  45 #include <linux/tty_driver.h>
  46 #include <linux/tty_flip.h>
  47 #include <linux/serial.h>
  48 #include <linux/module.h>
  49 #include <linux/moduleparam.h>
  50 #include <linux/spinlock.h>
  51 #include <linux/usb.h>
  52 #include <linux/usb/serial.h>
  53 #include <linux/uaccess.h>
  54 #include <linux/kfifo.h>
  55 #include "oti6858.h"
  56
  57 #define OTI6858_DESCRIPTION \
  58         "Ours Technology Inc. OTi-6858 USB to serial adapter driver"
  59 #define OTI6858_AUTHOR "Tomasz Michal Lukaszewski <FIXME@FIXME>"
  60
  61 static const struct usb_device_id id_table[] = {
  62         { USB_DEVICE(OTI6858_VENDOR_ID, OTI6858_PRODUCT_ID) },
  63         { }
  64 };
  65
  66 MODULE_DEVICE_TABLE(usb, id_table);
  67
  68 /* requests */
  69 #define OTI6858_REQ_GET_STATUS          (USB_DIR_IN | USB_TYPE_VENDOR | 0x00)
  70 #define OTI6858_REQ_T_GET_STATUS        0x01
  71
  72 #define OTI6858_REQ_SET_LINE            (USB_DIR_OUT | USB_TYPE_VENDOR | 0x00)
  73 #define OTI6858_REQ_T_SET_LINE          0x00
  74
  75 #define OTI6858_REQ_CHECK_TXBUFF        (USB_DIR_IN | USB_TYPE_VENDOR | 0x01)
  76 #define OTI6858_REQ_T_CHECK_TXBUFF      0x00
  77
  78 /* format of the control packet */
  79 struct oti6858_control_pkt {
  80         __le16  divisor;        /* baud rate = 96000000 / (16 * divisor), LE */
  81 #define OTI6858_MAX_BAUD_RATE   3000000
  82         u8      frame_fmt;
  83 #define FMT_STOP_BITS_MASK      0xc0
  84 #define FMT_STOP_BITS_1         0x00
  85 #define FMT_STOP_BITS_2         0x40    /* 1.5 stop bits if FMT_DATA_BITS_5 */
  86 #define FMT_PARITY_MASK         0x38
  87 #define FMT_PARITY_NONE         0x00
  88 #define FMT_PARITY_ODD          0x08
  89 #define FMT_PARITY_EVEN         0x18
  90 #define FMT_PARITY_MARK         0x28
  91 #define FMT_PARITY_SPACE        0x38
  92 #define FMT_DATA_BITS_MASK      0x03
  93 #define FMT_DATA_BITS_5         0x00
  94 #define FMT_DATA_BITS_6         0x01
  95 #define FMT_DATA_BITS_7         0x02
  96 #define FMT_DATA_BITS_8         0x03
  97         u8      something;      /* always equals 0x43 */
  98         u8      control;        /* settings of flow control lines */
  99 #define CONTROL_MASK            0x0c
 100 #define CONTROL_DTR_HIGH        0x08
 101 #define CONTROL_RTS_HIGH        0x04
 102         u8      tx_status;
 103 #define TX_BUFFER_EMPTIED       0x09
 104         u8      pin_state;
 105 #define PIN_MASK                0x3f
 106 #define PIN_RTS                 0x20    /* output pin */
 107 #define PIN_CTS                 0x10    /* input pin, active low */
 108 #define PIN_DSR                 0x08    /* input pin, active low */
 109 #define PIN_DTR                 0x04    /* output pin */
 110 #define PIN_RI                  0x02    /* input pin, active low */
 111 #define PIN_DCD                 0x01    /* input pin, active low */
 112         u8      rx_bytes_avail;         /* number of bytes in rx buffer */;
 113 };
 114
 115 #define OTI6858_CTRL_PKT_SIZE   sizeof(struct oti6858_control_pkt)
 116 #define OTI6858_CTRL_EQUALS_PENDING(a, priv) \
 117         (((a)->divisor == (priv)->pending_setup.divisor) \
 118           && ((a)->control == (priv)->pending_setup.control) \
 119           && ((a)->frame_fmt == (priv)->pending_setup.frame_fmt))
 120
 121 /* function prototypes */
 122 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port);
 123 static void oti6858_close(struct usb_serial_port *port);
 124 static void oti6858_set_termios(struct tty_struct *tty,
 125                         struct usb_serial_port *port, struct ktermios *old);
 126 static void oti6858_init_termios(struct tty_struct *tty);
 127 static void oti6858_read_int_callback(struct urb *urb);
 128 static void oti6858_read_bulk_callback(struct urb *urb);
 129 static void oti6858_write_bulk_callback(struct urb *urb);
 130 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 131                         const unsigned char *buf, int count);
 132 static int oti6858_write_room(struct tty_struct *tty);
 133 static int oti6858_chars_in_buffer(struct tty_struct *tty);
 134 static int oti6858_tiocmget(struct tty_struct *tty);
 135 static int oti6858_tiocmset(struct tty_struct *tty,
 136                                 unsigned int set, unsigned int clear);
 137 static int oti6858_tiocmiwait(struct tty_struct *tty, unsigned long arg);
 138 static int oti6858_port_probe(struct usb_serial_port *port);
 139 static int oti6858_port_remove(struct usb_serial_port *port);
 140
 141 /* device info */
 142 static struct usb_serial_driver oti6858_device = {
 143         .driver = {
 144                 .owner =        THIS_MODULE,
 145                 .name =         "oti6858",
 146         },
 147         .id_table =             id_table,
 148         .num_ports =            1,
 149         .open =                 oti6858_open,
 150         .close =                oti6858_close,
 151         .write =                oti6858_write,
 152         .set_termios =          oti6858_set_termios,
 153         .init_termios =         oti6858_init_termios,
 154         .tiocmget =             oti6858_tiocmget,
 155         .tiocmset =             oti6858_tiocmset,
 156         .tiocmiwait =           oti6858_tiocmiwait,
 157         .read_bulk_callback =   oti6858_read_bulk_callback,
 158         .read_int_callback =    oti6858_read_int_callback,
 159         .write_bulk_callback =  oti6858_write_bulk_callback,
 160         .write_room =           oti6858_write_room,
 161         .chars_in_buffer =      oti6858_chars_in_buffer,
 162         .port_probe =           oti6858_port_probe,
 163         .port_remove =          oti6858_port_remove,
 164 };
 165
 166 static struct usb_serial_driver * const serial_drivers[] = {
 167         &oti6858_device, NULL
 168 };
 169
 170 struct oti6858_private {
 171         spinlock_t lock;
 172
 173         struct oti6858_control_pkt status;
 174
 175         struct {
 176                 u8 read_urb_in_use;
 177                 u8 write_urb_in_use;
 178         } flags;
 179         struct delayed_work delayed_write_work;
 180
 181         struct {
 182                 __le16 divisor;
 183                 u8 frame_fmt;
 184                 u8 control;
 185         } pending_setup;
 186         u8 transient;
 187         u8 setup_done;
 188         struct delayed_work delayed_setup_work;
 189
 190         struct usb_serial_port *port;   /* USB port with which associated */
 191 };
 192
 193 static void setup_line(struct work_struct *work)
 194 {
 195         struct oti6858_private *priv = container_of(work,
 196                         struct oti6858_private, delayed_setup_work.work);
 197         struct usb_serial_port *port = priv->port;
 198         struct oti6858_control_pkt *new_setup;
 199         unsigned long flags;
 200         int result;
 201
 202         new_setup = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 203         if (new_setup == NULL) {
 204                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 205                 /* we will try again */
 206                 schedule_delayed_work(&priv->delayed_setup_work,
 207                                                 msecs_to_jiffies(2));
 208                 return;
 209         }
 210
 211         result = usb_control_msg(port->serial->dev,
 212                                 usb_rcvctrlpipe(port->serial->dev, 0),
 213                                 OTI6858_REQ_T_GET_STATUS,
 214                                 OTI6858_REQ_GET_STATUS,
 215                                 0, 0,
 216                                 new_setup, OTI6858_CTRL_PKT_SIZE,
 217                                 100);
 218
 219         if (result != OTI6858_CTRL_PKT_SIZE) {
 220                 dev_err(&port->dev, "%s(): error reading status\n", __func__);
 221                 kfree(new_setup);
 222                 /* we will try again */
 223                 schedule_delayed_work(&priv->delayed_setup_work,
 224                                                         msecs_to_jiffies(2));
 225                 return;
 226         }
 227
 228         spin_lock_irqsave(&priv->lock, flags);
 229         if (!OTI6858_CTRL_EQUALS_PENDING(new_setup, priv)) {
 230                 new_setup->divisor = priv->pending_setup.divisor;
 231                 new_setup->control = priv->pending_setup.control;
 232                 new_setup->frame_fmt = priv->pending_setup.frame_fmt;
 233
 234                 spin_unlock_irqrestore(&priv->lock, flags);
 235                 result = usb_control_msg(port->serial->dev,
 236                                         usb_sndctrlpipe(port->serial->dev, 0),
 237                                         OTI6858_REQ_T_SET_LINE,
 238                                         OTI6858_REQ_SET_LINE,
 239                                         0, 0,
 240                                         new_setup, OTI6858_CTRL_PKT_SIZE,
 241                                         100);
 242         } else {
 243                 spin_unlock_irqrestore(&priv->lock, flags);
 244                 result = 0;
 245         }
 246         kfree(new_setup);
 247
 248         spin_lock_irqsave(&priv->lock, flags);
 249         if (result != OTI6858_CTRL_PKT_SIZE)
 250                 priv->transient = 0;
 251         priv->setup_done = 1;
 252         spin_unlock_irqrestore(&priv->lock, flags);
 253
 254         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 255         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 256         if (result != 0) {
 257                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 258                         __func__, result);
 259         }
 260 }
 261
 262 static void send_data(struct work_struct *work)
 263 {
 264         struct oti6858_private *priv = container_of(work,
 265                         struct oti6858_private, delayed_write_work.work);
 266         struct usb_serial_port *port = priv->port;
 267         int count = 0, result;
 268         unsigned long flags;
 269         u8 *allow;
 270
 271         spin_lock_irqsave(&priv->lock, flags);
 272         if (priv->flags.write_urb_in_use) {
 273                 spin_unlock_irqrestore(&priv->lock, flags);
 274                 schedule_delayed_work(&priv->delayed_write_work,
 275                                                 msecs_to_jiffies(2));
 276                 return;
 277         }
 278         priv->flags.write_urb_in_use = 1;
 279         spin_unlock_irqrestore(&priv->lock, flags);
 280
 281         spin_lock_irqsave(&port->lock, flags);
 282         count = kfifo_len(&port->write_fifo);
 283         spin_unlock_irqrestore(&port->lock, flags);
 284
 285         if (count > port->bulk_out_size)
 286                 count = port->bulk_out_size;
 287
 288         if (count != 0) {
 289                 allow = kmalloc(1, GFP_KERNEL);
 290                 if (!allow) {
 291                         dev_err_console(port, "%s(): kmalloc failed\n",
 292                                         __func__);
 293                         return;
 294                 }
 295                 result = usb_control_msg(port->serial->dev,
 296                                 usb_rcvctrlpipe(port->serial->dev, 0),
 297                                 OTI6858_REQ_T_CHECK_TXBUFF,
 298                                 OTI6858_REQ_CHECK_TXBUFF,
 299                                 count, 0, allow, 1, 100);
 300                 if (result != 1 || *allow != 0)
 301                         count = 0;
 302                 kfree(allow);
 303         }
 304
 305         if (count == 0) {
 306                 priv->flags.write_urb_in_use = 0;
 307
 308                 dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 309                 result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
 310                 if (result != 0) {
 311                         dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 312                                 __func__, result);
 313                 }
 314                 return;
 315         }
 316
 317         count = kfifo_out_locked(&port->write_fifo,
 318                                         port->write_urb->transfer_buffer,
 319                                         count, &port->lock);
 320         port->write_urb->transfer_buffer_length = count;
 321         result = usb_submit_urb(port->write_urb, GFP_NOIO);
 322         if (result != 0) {
 323                 dev_err_console(port, "%s(): usb_submit_urb() failed with error %d\n",
 324                                 __func__, result);
 325                 priv->flags.write_urb_in_use = 0;
 326         }
 327
 328         usb_serial_port_softint(port);
 329 }
 330
 331 static int oti6858_port_probe(struct usb_serial_port *port)
 332 {
 333         struct oti6858_private *priv;
 334
 335         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 336         if (!priv)
 337                 return -ENOMEM;
 338
 339         spin_lock_init(&priv->lock);
 340         priv->port = port;
 341         INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 342         INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 343
 344         usb_set_serial_port_data(port, priv);
 345
 346         return 0;
 347 }
 348
 349 static int oti6858_port_remove(struct usb_serial_port *port)
 350 {
 351         struct oti6858_private *priv;
 352
 353         priv = usb_get_serial_port_data(port);
 354         kfree(priv);
 355
 356         return 0;
 357 }
 358
 359 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 360                         const unsigned char *buf, int count)
 361 {
 362         if (!count)
 363                 return count;
 364
 365         count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
 366
 367         return count;
 368 }
 369
 370 static int oti6858_write_room(struct tty_struct *tty)
 371 {
 372         struct usb_serial_port *port = tty->driver_data;
 373         int room = 0;
 374         unsigned long flags;
 375
 376         spin_lock_irqsave(&port->lock, flags);
 377         room = kfifo_avail(&port->write_fifo);
 378         spin_unlock_irqrestore(&port->lock, flags);
 379
 380         return room;
 381 }
 382
 383 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 384 {
 385         struct usb_serial_port *port = tty->driver_data;
 386         int chars = 0;
 387         unsigned long flags;
 388
 389         spin_lock_irqsave(&port->lock, flags);
 390         chars = kfifo_len(&port->write_fifo);
 391         spin_unlock_irqrestore(&port->lock, flags);
 392
 393         return chars;
 394 }
 395
 396 static void oti6858_init_termios(struct tty_struct *tty)
 397 {
 398         tty->termios = tty_std_termios;
 399         tty->termios.c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
 400         tty->termios.c_ispeed = 38400;
 401         tty->termios.c_ospeed = 38400;
 402 }
 403
 404 static void oti6858_set_termios(struct tty_struct *tty,
 405                 struct usb_serial_port *port, struct ktermios *old_termios)
 406 {
 407         struct oti6858_private *priv = usb_get_serial_port_data(port);
 408         unsigned long flags;
 409         unsigned int cflag;
 410         u8 frame_fmt, control;
 411         __le16 divisor;
 412         int br;
 413
 414         if (!tty)
 415                 return;
 416
 417         cflag = tty->termios.c_cflag;
 418
 419         spin_lock_irqsave(&priv->lock, flags);
 420         divisor = priv->pending_setup.divisor;
 421         frame_fmt = priv->pending_setup.frame_fmt;
 422         control = priv->pending_setup.control;
 423         spin_unlock_irqrestore(&priv->lock, flags);
 424
 425         frame_fmt &= ~FMT_DATA_BITS_MASK;
 426         switch (cflag & CSIZE) {
 427         case CS5:
 428                 frame_fmt |= FMT_DATA_BITS_5;
 429                 break;
 430         case CS6:
 431                 frame_fmt |= FMT_DATA_BITS_6;
 432                 break;
 433         case CS7:
 434                 frame_fmt |= FMT_DATA_BITS_7;
 435                 break;
 436         default:
 437         case CS8:
 438                 frame_fmt |= FMT_DATA_BITS_8;
 439                 break;
 440         }
 441
 442         /* manufacturer claims that this device can work with baud rates
 443          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 444          * guarantee that any other baud rate will work (especially
 445          * the higher ones)
 446          */
 447         br = tty_get_baud_rate(tty);
 448         if (br == 0) {
 449                 divisor = 0;
 450         } else {
 451                 int real_br;
 452                 int new_divisor;
 453                 br = min(br, OTI6858_MAX_BAUD_RATE);
 454
 455                 new_divisor = (96000000 + 8 * br) / (16 * br);
 456                 real_br = 96000000 / (16 * new_divisor);
 457                 divisor = cpu_to_le16(new_divisor);
 458                 tty_encode_baud_rate(tty, real_br, real_br);
 459         }
 460
 461         frame_fmt &= ~FMT_STOP_BITS_MASK;
 462         if ((cflag & CSTOPB) != 0)
 463                 frame_fmt |= FMT_STOP_BITS_2;
 464         else
 465                 frame_fmt |= FMT_STOP_BITS_1;
 466
 467         frame_fmt &= ~FMT_PARITY_MASK;
 468         if ((cflag & PARENB) != 0) {
 469                 if ((cflag & PARODD) != 0)
 470                         frame_fmt |= FMT_PARITY_ODD;
 471                 else
 472                         frame_fmt |= FMT_PARITY_EVEN;
 473         } else {
 474                 frame_fmt |= FMT_PARITY_NONE;
 475         }
 476
 477         control &= ~CONTROL_MASK;
 478         if ((cflag & CRTSCTS) != 0)
 479                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 480
 481         /* change control lines if we are switching to or from B0 */
 482         /* FIXME:
 483         spin_lock_irqsave(&priv->lock, flags);
 484         control = priv->line_control;
 485         if ((cflag & CBAUD) == B0)
 486                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 487         else
 488                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 489         if (control != priv->line_control) {
 490                 control = priv->line_control;
 491                 spin_unlock_irqrestore(&priv->lock, flags);
 492                 set_control_lines(serial->dev, control);
 493         } else {
 494                 spin_unlock_irqrestore(&priv->lock, flags);
 495         }
 496         */
 497
 498         spin_lock_irqsave(&priv->lock, flags);
 499         if (divisor != priv->pending_setup.divisor
 500                         || control != priv->pending_setup.control
 501                         || frame_fmt != priv->pending_setup.frame_fmt) {
 502                 priv->pending_setup.divisor = divisor;
 503                 priv->pending_setup.control = control;
 504                 priv->pending_setup.frame_fmt = frame_fmt;
 505         }
 506         spin_unlock_irqrestore(&priv->lock, flags);
 507 }
 508
 509 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
 510 {
 511         struct oti6858_private *priv = usb_get_serial_port_data(port);
 512         struct ktermios tmp_termios;
 513         struct usb_serial *serial = port->serial;
 514         struct oti6858_control_pkt *buf;
 515         unsigned long flags;
 516         int result;
 517
 518         usb_clear_halt(serial->dev, port->write_urb->pipe);
 519         usb_clear_halt(serial->dev, port->read_urb->pipe);
 520
 521         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 522         if (buf == NULL) {
 523                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 524                 return -ENOMEM;
 525         }
 526
 527         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 528                                 OTI6858_REQ_T_GET_STATUS,
 529                                 OTI6858_REQ_GET_STATUS,
 530                                 0, 0,
 531                                 buf, OTI6858_CTRL_PKT_SIZE,
 532                                 100);
 533         if (result != OTI6858_CTRL_PKT_SIZE) {
 534                 /* assume default (after power-on reset) values */
 535                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 536                 buf->frame_fmt = 0x03;  /* 8N1 */
 537                 buf->something = 0x43;
 538                 buf->control = 0x4c;    /* DTR, RTS */
 539                 buf->tx_status = 0x00;
 540                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 541                 buf->rx_bytes_avail = 0x00;
 542         }
 543
 544         spin_lock_irqsave(&priv->lock, flags);
 545         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 546         priv->pending_setup.divisor = buf->divisor;
 547         priv->pending_setup.frame_fmt = buf->frame_fmt;
 548         priv->pending_setup.control = buf->control;
 549         spin_unlock_irqrestore(&priv->lock, flags);
 550         kfree(buf);
 551
 552         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 553         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 554         if (result != 0) {
 555                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 556                         __func__, result);
 557                 oti6858_close(port);
 558                 return result;
 559         }
 560
 561         /* setup termios */
 562         if (tty)
 563                 oti6858_set_termios(tty, port, &tmp_termios);
 564         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 565         return 0;
 566 }
 567
 568 static void oti6858_close(struct usb_serial_port *port)
 569 {
 570         struct oti6858_private *priv = usb_get_serial_port_data(port);
 571         unsigned long flags;
 572
 573         spin_lock_irqsave(&port->lock, flags);
 574         /* clear out any remaining data in the buffer */
 575         kfifo_reset_out(&port->write_fifo);
 576         spin_unlock_irqrestore(&port->lock, flags);
 577
 578         dev_dbg(&port->dev, "%s(): after buf_clear()\n", __func__);
 579
 580         /* cancel scheduled setup */
 581         cancel_delayed_work_sync(&priv->delayed_setup_work);
 582         cancel_delayed_work_sync(&priv->delayed_write_work);
 583
 584         /* shutdown our urbs */
 585         dev_dbg(&port->dev, "%s(): shutting down urbs\n", __func__);
 586         usb_kill_urb(port->write_urb);
 587         usb_kill_urb(port->read_urb);
 588         usb_kill_urb(port->interrupt_in_urb);
 589 }
 590
 591 static int oti6858_tiocmset(struct tty_struct *tty,
 592                                 unsigned int set, unsigned int clear)
 593 {
 594         struct usb_serial_port *port = tty->driver_data;
 595         struct oti6858_private *priv = usb_get_serial_port_data(port);
 596         unsigned long flags;
 597         u8 control;
 598
 599         dev_dbg(&port->dev, "%s(set = 0x%08x, clear = 0x%08x)\n",
 600                 __func__, set, clear);
 601
 602         /* FIXME: check if this is correct (active high/low) */
 603         spin_lock_irqsave(&priv->lock, flags);
 604         control = priv->pending_setup.control;
 605         if ((set & TIOCM_RTS) != 0)
 606                 control |= CONTROL_RTS_HIGH;
 607         if ((set & TIOCM_DTR) != 0)
 608                 control |= CONTROL_DTR_HIGH;
 609         if ((clear & TIOCM_RTS) != 0)
 610                 control &= ~CONTROL_RTS_HIGH;
 611         if ((clear & TIOCM_DTR) != 0)
 612                 control &= ~CONTROL_DTR_HIGH;
 613
 614         if (control != priv->pending_setup.control)
 615                 priv->pending_setup.control = control;
 616
 617         spin_unlock_irqrestore(&priv->lock, flags);
 618         return 0;
 619 }
 620
 621 static int oti6858_tiocmget(struct tty_struct *tty)
 622 {
 623         struct usb_serial_port *port = tty->driver_data;
 624         struct oti6858_private *priv = usb_get_serial_port_data(port);
 625         unsigned long flags;
 626         unsigned pin_state;
 627         unsigned result = 0;
 628
 629         spin_lock_irqsave(&priv->lock, flags);
 630         pin_state = priv->status.pin_state & PIN_MASK;
 631         spin_unlock_irqrestore(&priv->lock, flags);
 632
 633         /* FIXME: check if this is correct (active high/low) */
 634         if ((pin_state & PIN_RTS) != 0)
 635                 result |= TIOCM_RTS;
 636         if ((pin_state & PIN_CTS) != 0)
 637                 result |= TIOCM_CTS;
 638         if ((pin_state & PIN_DSR) != 0)
 639                 result |= TIOCM_DSR;
 640         if ((pin_state & PIN_DTR) != 0)
 641                 result |= TIOCM_DTR;
 642         if ((pin_state & PIN_RI) != 0)
 643                 result |= TIOCM_RI;
 644         if ((pin_state & PIN_DCD) != 0)
 645                 result |= TIOCM_CD;
 646
 647         dev_dbg(&port->dev, "%s() = 0x%08x\n", __func__, result);
 648
 649         return result;
 650 }
 651
 652 static int oti6858_tiocmiwait(struct tty_struct *tty, unsigned long arg)
 653 {
 654         struct usb_serial_port *port = tty->driver_data;
 655         struct oti6858_private *priv = usb_get_serial_port_data(port);
 656         unsigned long flags;
 657         unsigned int prev, status;
 658         unsigned int changed;
 659
 660         spin_lock_irqsave(&priv->lock, flags);
 661         prev = priv->status.pin_state;
 662         spin_unlock_irqrestore(&priv->lock, flags);
 663
 664         while (1) {
 665                 wait_event_interruptible(port->port.delta_msr_wait,
 666                                         port->serial->disconnected ||
 667                                         priv->status.pin_state != prev);
 668                 if (signal_pending(current))
 669                         return -ERESTARTSYS;
 670
 671                 if (port->serial->disconnected)
 672                         return -EIO;
 673
 674                 spin_lock_irqsave(&priv->lock, flags);
 675                 status = priv->status.pin_state & PIN_MASK;
 676                 spin_unlock_irqrestore(&priv->lock, flags);
 677
 678                 changed = prev ^ status;
 679                 /* FIXME: check if this is correct (active high/low) */
 680                 if (((arg & TIOCM_RNG) && (changed & PIN_RI)) ||
 681                     ((arg & TIOCM_DSR) && (changed & PIN_DSR)) ||
 682                     ((arg & TIOCM_CD)  && (changed & PIN_DCD)) ||
 683                     ((arg & TIOCM_CTS) && (changed & PIN_CTS)))
 684                         return 0;
 685                 prev = status;
 686         }
 687
 688         /* NOTREACHED */
 689         return 0;
 690 }
 691
 692 static void oti6858_read_int_callback(struct urb *urb)
 693 {
 694         struct usb_serial_port *port =  urb->context;
 695         struct oti6858_private *priv = usb_get_serial_port_data(port);
 696         int transient = 0, can_recv = 0, resubmit = 1;
 697         int status = urb->status;
 698
 699         switch (status) {
 700         case 0:
 701                 /* success */
 702                 break;
 703         case -ECONNRESET:
 704         case -ENOENT:
 705         case -ESHUTDOWN:
 706                 /* this urb is terminated, clean up */
 707                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n",
 708                         __func__, status);
 709                 return;
 710         default:
 711                 dev_dbg(&urb->dev->dev, "%s(): nonzero urb status received: %d\n",
 712                         __func__, status);
 713                 break;
 714         }
 715
 716         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 717                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 718                 unsigned long flags;
 719
 720                 spin_lock_irqsave(&priv->lock, flags);
 721
 722                 if (!priv->transient) {
 723                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 724                                 if (xs->rx_bytes_avail == 0) {
 725                                         priv->transient = 4;
 726                                         priv->setup_done = 0;
 727                                         resubmit = 0;
 728                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 729                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 730                                 }
 731                         }
 732                 } else {
 733                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 734                                 priv->transient = 0;
 735                         } else if (!priv->setup_done) {
 736                                 resubmit = 0;
 737                         } else if (--priv->transient == 0) {
 738                                 if (xs->rx_bytes_avail == 0) {
 739                                         priv->transient = 4;
 740                                         priv->setup_done = 0;
 741                                         resubmit = 0;
 742                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 743                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 744                                 }
 745                         }
 746                 }
 747
 748                 if (!priv->transient) {
 749                         if (xs->pin_state != priv->status.pin_state)
 750                                 wake_up_interruptible(&port->port.delta_msr_wait);
 751                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 752                 }
 753
 754                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 755                         can_recv = xs->rx_bytes_avail;
 756                         priv->flags.read_urb_in_use = 1;
 757                 }
 758
 759                 transient = priv->transient;
 760                 spin_unlock_irqrestore(&priv->lock, flags);
 761         }
 762
 763         if (can_recv) {
 764                 int result;
 765
 766                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 767                 if (result != 0) {
 768                         priv->flags.read_urb_in_use = 0;
 769                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 770                                         " error %d\n", __func__, result);
 771                 } else {
 772                         resubmit = 0;
 773                 }
 774         } else if (!transient) {
 775                 unsigned long flags;
 776                 int count;
 777
 778                 spin_lock_irqsave(&port->lock, flags);
 779                 count = kfifo_len(&port->write_fifo);
 780                 spin_unlock_irqrestore(&port->lock, flags);
 781
 782                 spin_lock_irqsave(&priv->lock, flags);
 783                 if (priv->flags.write_urb_in_use == 0 && count != 0) {
 784                         schedule_delayed_work(&priv->delayed_write_work, 0);
 785                         resubmit = 0;
 786                 }
 787                 spin_unlock_irqrestore(&priv->lock, flags);
 788         }
 789
 790         if (resubmit) {
 791                 int result;
 792
 793 /*              dev_dbg(&urb->dev->dev, "%s(): submitting interrupt urb\n", __func__); */
 794                 result = usb_submit_urb(urb, GFP_ATOMIC);
 795                 if (result != 0) {
 796                         dev_err(&urb->dev->dev,
 797                                         "%s(): usb_submit_urb() failed with"
 798                                         " error %d\n", __func__, result);
 799                 }
 800         }
 801 }
 802
 803 static void oti6858_read_bulk_callback(struct urb *urb)
 804 {
 805         struct usb_serial_port *port =  urb->context;
 806         struct oti6858_private *priv = usb_get_serial_port_data(port);
 807         unsigned char *data = urb->transfer_buffer;
 808         unsigned long flags;
 809         int status = urb->status;
 810         int result;
 811
 812         spin_lock_irqsave(&priv->lock, flags);
 813         priv->flags.read_urb_in_use = 0;
 814         spin_unlock_irqrestore(&priv->lock, flags);
 815
 816         if (status != 0) {
 817                 dev_dbg(&urb->dev->dev, "%s(): unable to handle the error, exiting\n", __func__);
 818                 return;
 819         }
 820
 821         if (urb->actual_length > 0) {
 822                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 823                 tty_flip_buffer_push(&port->port);
 824         }
 825
 826         /* schedule the interrupt urb */
 827         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 828         if (result != 0 && result != -EPERM) {
 829                 dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 830                                 " error %d\n", __func__, result);
 831         }
 832 }
 833
 834 static void oti6858_write_bulk_callback(struct urb *urb)
 835 {
 836         struct usb_serial_port *port =  urb->context;
 837         struct oti6858_private *priv = usb_get_serial_port_data(port);
 838         int status = urb->status;
 839         int result;
 840
 841         switch (status) {
 842         case 0:
 843                 /* success */
 844                 break;
 845         case -ECONNRESET:
 846         case -ENOENT:
 847         case -ESHUTDOWN:
 848                 /* this urb is terminated, clean up */
 849                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n", __func__, status);
 850                 priv->flags.write_urb_in_use = 0;
 851                 return;
 852         default:
 853                 /* error in the urb, so we have to resubmit it */
 854                 dev_dbg(&urb->dev->dev, "%s(): nonzero write bulk status received: %d\n", __func__, status);
 855                 dev_dbg(&urb->dev->dev, "%s(): overflow in write\n", __func__);
 856
 857                 port->write_urb->transfer_buffer_length = 1;
 858                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 859                 if (result) {
 860                         dev_err_console(port, "%s(): usb_submit_urb() failed,"
 861                                         " error %d\n", __func__, result);
 862                 } else {
 863                         return;
 864                 }
 865         }
 866
 867         priv->flags.write_urb_in_use = 0;
 868
 869         /* schedule the interrupt urb if we are still open */
 870         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 871         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 872         if (result != 0) {
 873                 dev_err(&port->dev, "%s(): failed submitting int urb,"
 874                                         " error %d\n", __func__, result);
 875         }
 876 }
 877
 878 module_usb_serial_driver(serial_drivers, id_table);
 879
 880 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
 881 MODULE_AUTHOR(OTI6858_AUTHOR);
 882 MODULE_LICENSE("GPL");