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) {
 204                 /* we will try again */
 205                 schedule_delayed_work(&priv->delayed_setup_work,
 206                                                 msecs_to_jiffies(2));
 207                 return;
 208         }
 209
 210         result = usb_control_msg(port->serial->dev,
 211                                 usb_rcvctrlpipe(port->serial->dev, 0),
 212                                 OTI6858_REQ_T_GET_STATUS,
 213                                 OTI6858_REQ_GET_STATUS,
 214                                 0, 0,
 215                                 new_setup, OTI6858_CTRL_PKT_SIZE,
 216                                 100);
 217
 218         if (result != OTI6858_CTRL_PKT_SIZE) {
 219                 dev_err(&port->dev, "%s(): error reading status\n", __func__);
 220                 kfree(new_setup);
 221                 /* we will try again */
 222                 schedule_delayed_work(&priv->delayed_setup_work,
 223                                                         msecs_to_jiffies(2));
 224                 return;
 225         }
 226
 227         spin_lock_irqsave(&priv->lock, flags);
 228         if (!OTI6858_CTRL_EQUALS_PENDING(new_setup, priv)) {
 229                 new_setup->divisor = priv->pending_setup.divisor;
 230                 new_setup->control = priv->pending_setup.control;
 231                 new_setup->frame_fmt = priv->pending_setup.frame_fmt;
 232
 233                 spin_unlock_irqrestore(&priv->lock, flags);
 234                 result = usb_control_msg(port->serial->dev,
 235                                         usb_sndctrlpipe(port->serial->dev, 0),
 236                                         OTI6858_REQ_T_SET_LINE,
 237                                         OTI6858_REQ_SET_LINE,
 238                                         0, 0,
 239                                         new_setup, OTI6858_CTRL_PKT_SIZE,
 240                                         100);
 241         } else {
 242                 spin_unlock_irqrestore(&priv->lock, flags);
 243                 result = 0;
 244         }
 245         kfree(new_setup);
 246
 247         spin_lock_irqsave(&priv->lock, flags);
 248         if (result != OTI6858_CTRL_PKT_SIZE)
 249                 priv->transient = 0;
 250         priv->setup_done = 1;
 251         spin_unlock_irqrestore(&priv->lock, flags);
 252
 253         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 254         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 255         if (result != 0) {
 256                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 257                         __func__, result);
 258         }
 259 }
 260
 261 static void send_data(struct work_struct *work)
 262 {
 263         struct oti6858_private *priv = container_of(work,
 264                         struct oti6858_private, delayed_write_work.work);
 265         struct usb_serial_port *port = priv->port;
 266         int count = 0, result;
 267         unsigned long flags;
 268         u8 *allow;
 269
 270         spin_lock_irqsave(&priv->lock, flags);
 271         if (priv->flags.write_urb_in_use) {
 272                 spin_unlock_irqrestore(&priv->lock, flags);
 273                 schedule_delayed_work(&priv->delayed_write_work,
 274                                                 msecs_to_jiffies(2));
 275                 return;
 276         }
 277         priv->flags.write_urb_in_use = 1;
 278         spin_unlock_irqrestore(&priv->lock, flags);
 279
 280         spin_lock_irqsave(&port->lock, flags);
 281         count = kfifo_len(&port->write_fifo);
 282         spin_unlock_irqrestore(&port->lock, flags);
 283
 284         if (count > port->bulk_out_size)
 285                 count = port->bulk_out_size;
 286
 287         if (count != 0) {
 288                 allow = kmalloc(1, GFP_KERNEL);
 289                 if (!allow)
 290                         return;
 291
 292                 result = usb_control_msg(port->serial->dev,
 293                                 usb_rcvctrlpipe(port->serial->dev, 0),
 294                                 OTI6858_REQ_T_CHECK_TXBUFF,
 295                                 OTI6858_REQ_CHECK_TXBUFF,
 296                                 count, 0, allow, 1, 100);
 297                 if (result != 1 || *allow != 0)
 298                         count = 0;
 299                 kfree(allow);
 300         }
 301
 302         if (count == 0) {
 303                 priv->flags.write_urb_in_use = 0;
 304
 305                 dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 306                 result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
 307                 if (result != 0) {
 308                         dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 309                                 __func__, result);
 310                 }
 311                 return;
 312         }
 313
 314         count = kfifo_out_locked(&port->write_fifo,
 315                                         port->write_urb->transfer_buffer,
 316                                         count, &port->lock);
 317         port->write_urb->transfer_buffer_length = count;
 318         result = usb_submit_urb(port->write_urb, GFP_NOIO);
 319         if (result != 0) {
 320                 dev_err_console(port, "%s(): usb_submit_urb() failed with error %d\n",
 321                                 __func__, result);
 322                 priv->flags.write_urb_in_use = 0;
 323         }
 324
 325         usb_serial_port_softint(port);
 326 }
 327
 328 static int oti6858_port_probe(struct usb_serial_port *port)
 329 {
 330         struct oti6858_private *priv;
 331
 332         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 333         if (!priv)
 334                 return -ENOMEM;
 335
 336         spin_lock_init(&priv->lock);
 337         priv->port = port;
 338         INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 339         INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 340
 341         usb_set_serial_port_data(port, priv);
 342
 343         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 344
 345         return 0;
 346 }
 347
 348 static int oti6858_port_remove(struct usb_serial_port *port)
 349 {
 350         struct oti6858_private *priv;
 351
 352         priv = usb_get_serial_port_data(port);
 353         kfree(priv);
 354
 355         return 0;
 356 }
 357
 358 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 359                         const unsigned char *buf, int count)
 360 {
 361         if (!count)
 362                 return count;
 363
 364         count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
 365
 366         return count;
 367 }
 368
 369 static int oti6858_write_room(struct tty_struct *tty)
 370 {
 371         struct usb_serial_port *port = tty->driver_data;
 372         int room = 0;
 373         unsigned long flags;
 374
 375         spin_lock_irqsave(&port->lock, flags);
 376         room = kfifo_avail(&port->write_fifo);
 377         spin_unlock_irqrestore(&port->lock, flags);
 378
 379         return room;
 380 }
 381
 382 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 383 {
 384         struct usb_serial_port *port = tty->driver_data;
 385         int chars = 0;
 386         unsigned long flags;
 387
 388         spin_lock_irqsave(&port->lock, flags);
 389         chars = kfifo_len(&port->write_fifo);
 390         spin_unlock_irqrestore(&port->lock, flags);
 391
 392         return chars;
 393 }
 394
 395 static void oti6858_init_termios(struct tty_struct *tty)
 396 {
 397         tty->termios = tty_std_termios;
 398         tty->termios.c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
 399         tty->termios.c_ispeed = 38400;
 400         tty->termios.c_ospeed = 38400;
 401 }
 402
 403 static void oti6858_set_termios(struct tty_struct *tty,
 404                 struct usb_serial_port *port, struct ktermios *old_termios)
 405 {
 406         struct oti6858_private *priv = usb_get_serial_port_data(port);
 407         unsigned long flags;
 408         unsigned int cflag;
 409         u8 frame_fmt, control;
 410         __le16 divisor;
 411         int br;
 412
 413         cflag = tty->termios.c_cflag;
 414
 415         spin_lock_irqsave(&priv->lock, flags);
 416         divisor = priv->pending_setup.divisor;
 417         frame_fmt = priv->pending_setup.frame_fmt;
 418         control = priv->pending_setup.control;
 419         spin_unlock_irqrestore(&priv->lock, flags);
 420
 421         frame_fmt &= ~FMT_DATA_BITS_MASK;
 422         switch (cflag & CSIZE) {
 423         case CS5:
 424                 frame_fmt |= FMT_DATA_BITS_5;
 425                 break;
 426         case CS6:
 427                 frame_fmt |= FMT_DATA_BITS_6;
 428                 break;
 429         case CS7:
 430                 frame_fmt |= FMT_DATA_BITS_7;
 431                 break;
 432         default:
 433         case CS8:
 434                 frame_fmt |= FMT_DATA_BITS_8;
 435                 break;
 436         }
 437
 438         /* manufacturer claims that this device can work with baud rates
 439          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 440          * guarantee that any other baud rate will work (especially
 441          * the higher ones)
 442          */
 443         br = tty_get_baud_rate(tty);
 444         if (br == 0) {
 445                 divisor = 0;
 446         } else {
 447                 int real_br;
 448                 int new_divisor;
 449                 br = min(br, OTI6858_MAX_BAUD_RATE);
 450
 451                 new_divisor = (96000000 + 8 * br) / (16 * br);
 452                 real_br = 96000000 / (16 * new_divisor);
 453                 divisor = cpu_to_le16(new_divisor);
 454                 tty_encode_baud_rate(tty, real_br, real_br);
 455         }
 456
 457         frame_fmt &= ~FMT_STOP_BITS_MASK;
 458         if ((cflag & CSTOPB) != 0)
 459                 frame_fmt |= FMT_STOP_BITS_2;
 460         else
 461                 frame_fmt |= FMT_STOP_BITS_1;
 462
 463         frame_fmt &= ~FMT_PARITY_MASK;
 464         if ((cflag & PARENB) != 0) {
 465                 if ((cflag & PARODD) != 0)
 466                         frame_fmt |= FMT_PARITY_ODD;
 467                 else
 468                         frame_fmt |= FMT_PARITY_EVEN;
 469         } else {
 470                 frame_fmt |= FMT_PARITY_NONE;
 471         }
 472
 473         control &= ~CONTROL_MASK;
 474         if ((cflag & CRTSCTS) != 0)
 475                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 476
 477         /* change control lines if we are switching to or from B0 */
 478         /* FIXME:
 479         spin_lock_irqsave(&priv->lock, flags);
 480         control = priv->line_control;
 481         if ((cflag & CBAUD) == B0)
 482                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 483         else
 484                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 485         if (control != priv->line_control) {
 486                 control = priv->line_control;
 487                 spin_unlock_irqrestore(&priv->lock, flags);
 488                 set_control_lines(serial->dev, control);
 489         } else {
 490                 spin_unlock_irqrestore(&priv->lock, flags);
 491         }
 492         */
 493
 494         spin_lock_irqsave(&priv->lock, flags);
 495         if (divisor != priv->pending_setup.divisor
 496                         || control != priv->pending_setup.control
 497                         || frame_fmt != priv->pending_setup.frame_fmt) {
 498                 priv->pending_setup.divisor = divisor;
 499                 priv->pending_setup.control = control;
 500                 priv->pending_setup.frame_fmt = frame_fmt;
 501         }
 502         spin_unlock_irqrestore(&priv->lock, flags);
 503 }
 504
 505 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
 506 {
 507         struct oti6858_private *priv = usb_get_serial_port_data(port);
 508         struct usb_serial *serial = port->serial;
 509         struct oti6858_control_pkt *buf;
 510         unsigned long flags;
 511         int result;
 512
 513         usb_clear_halt(serial->dev, port->write_urb->pipe);
 514         usb_clear_halt(serial->dev, port->read_urb->pipe);
 515
 516         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 517         if (!buf)
 518                 return -ENOMEM;
 519
 520         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 521                                 OTI6858_REQ_T_GET_STATUS,
 522                                 OTI6858_REQ_GET_STATUS,
 523                                 0, 0,
 524                                 buf, OTI6858_CTRL_PKT_SIZE,
 525                                 100);
 526         if (result != OTI6858_CTRL_PKT_SIZE) {
 527                 /* assume default (after power-on reset) values */
 528                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 529                 buf->frame_fmt = 0x03;  /* 8N1 */
 530                 buf->something = 0x43;
 531                 buf->control = 0x4c;    /* DTR, RTS */
 532                 buf->tx_status = 0x00;
 533                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 534                 buf->rx_bytes_avail = 0x00;
 535         }
 536
 537         spin_lock_irqsave(&priv->lock, flags);
 538         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 539         priv->pending_setup.divisor = buf->divisor;
 540         priv->pending_setup.frame_fmt = buf->frame_fmt;
 541         priv->pending_setup.control = buf->control;
 542         spin_unlock_irqrestore(&priv->lock, flags);
 543         kfree(buf);
 544
 545         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 546         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 547         if (result != 0) {
 548                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 549                         __func__, result);
 550                 oti6858_close(port);
 551                 return result;
 552         }
 553
 554         /* setup termios */
 555         if (tty)
 556                 oti6858_set_termios(tty, port, NULL);
 557
 558         return 0;
 559 }
 560
 561 static void oti6858_close(struct usb_serial_port *port)
 562 {
 563         struct oti6858_private *priv = usb_get_serial_port_data(port);
 564         unsigned long flags;
 565
 566         spin_lock_irqsave(&port->lock, flags);
 567         /* clear out any remaining data in the buffer */
 568         kfifo_reset_out(&port->write_fifo);
 569         spin_unlock_irqrestore(&port->lock, flags);
 570
 571         dev_dbg(&port->dev, "%s(): after buf_clear()\n", __func__);
 572
 573         /* cancel scheduled setup */
 574         cancel_delayed_work_sync(&priv->delayed_setup_work);
 575         cancel_delayed_work_sync(&priv->delayed_write_work);
 576
 577         /* shutdown our urbs */
 578         dev_dbg(&port->dev, "%s(): shutting down urbs\n", __func__);
 579         usb_kill_urb(port->write_urb);
 580         usb_kill_urb(port->read_urb);
 581         usb_kill_urb(port->interrupt_in_urb);
 582 }
 583
 584 static int oti6858_tiocmset(struct tty_struct *tty,
 585                                 unsigned int set, unsigned int clear)
 586 {
 587         struct usb_serial_port *port = tty->driver_data;
 588         struct oti6858_private *priv = usb_get_serial_port_data(port);
 589         unsigned long flags;
 590         u8 control;
 591
 592         dev_dbg(&port->dev, "%s(set = 0x%08x, clear = 0x%08x)\n",
 593                 __func__, set, clear);
 594
 595         /* FIXME: check if this is correct (active high/low) */
 596         spin_lock_irqsave(&priv->lock, flags);
 597         control = priv->pending_setup.control;
 598         if ((set & TIOCM_RTS) != 0)
 599                 control |= CONTROL_RTS_HIGH;
 600         if ((set & TIOCM_DTR) != 0)
 601                 control |= CONTROL_DTR_HIGH;
 602         if ((clear & TIOCM_RTS) != 0)
 603                 control &= ~CONTROL_RTS_HIGH;
 604         if ((clear & TIOCM_DTR) != 0)
 605                 control &= ~CONTROL_DTR_HIGH;
 606
 607         if (control != priv->pending_setup.control)
 608                 priv->pending_setup.control = control;
 609
 610         spin_unlock_irqrestore(&priv->lock, flags);
 611         return 0;
 612 }
 613
 614 static int oti6858_tiocmget(struct tty_struct *tty)
 615 {
 616         struct usb_serial_port *port = tty->driver_data;
 617         struct oti6858_private *priv = usb_get_serial_port_data(port);
 618         unsigned long flags;
 619         unsigned pin_state;
 620         unsigned result = 0;
 621
 622         spin_lock_irqsave(&priv->lock, flags);
 623         pin_state = priv->status.pin_state & PIN_MASK;
 624         spin_unlock_irqrestore(&priv->lock, flags);
 625
 626         /* FIXME: check if this is correct (active high/low) */
 627         if ((pin_state & PIN_RTS) != 0)
 628                 result |= TIOCM_RTS;
 629         if ((pin_state & PIN_CTS) != 0)
 630                 result |= TIOCM_CTS;
 631         if ((pin_state & PIN_DSR) != 0)
 632                 result |= TIOCM_DSR;
 633         if ((pin_state & PIN_DTR) != 0)
 634                 result |= TIOCM_DTR;
 635         if ((pin_state & PIN_RI) != 0)
 636                 result |= TIOCM_RI;
 637         if ((pin_state & PIN_DCD) != 0)
 638                 result |= TIOCM_CD;
 639
 640         dev_dbg(&port->dev, "%s() = 0x%08x\n", __func__, result);
 641
 642         return result;
 643 }
 644
 645 static int oti6858_tiocmiwait(struct tty_struct *tty, unsigned long arg)
 646 {
 647         struct usb_serial_port *port = tty->driver_data;
 648         struct oti6858_private *priv = usb_get_serial_port_data(port);
 649         unsigned long flags;
 650         unsigned int prev, status;
 651         unsigned int changed;
 652
 653         spin_lock_irqsave(&priv->lock, flags);
 654         prev = priv->status.pin_state;
 655         spin_unlock_irqrestore(&priv->lock, flags);
 656
 657         while (1) {
 658                 wait_event_interruptible(port->port.delta_msr_wait,
 659                                         port->serial->disconnected ||
 660                                         priv->status.pin_state != prev);
 661                 if (signal_pending(current))
 662                         return -ERESTARTSYS;
 663
 664                 if (port->serial->disconnected)
 665                         return -EIO;
 666
 667                 spin_lock_irqsave(&priv->lock, flags);
 668                 status = priv->status.pin_state & PIN_MASK;
 669                 spin_unlock_irqrestore(&priv->lock, flags);
 670
 671                 changed = prev ^ status;
 672                 /* FIXME: check if this is correct (active high/low) */
 673                 if (((arg & TIOCM_RNG) && (changed & PIN_RI)) ||
 674                     ((arg & TIOCM_DSR) && (changed & PIN_DSR)) ||
 675                     ((arg & TIOCM_CD)  && (changed & PIN_DCD)) ||
 676                     ((arg & TIOCM_CTS) && (changed & PIN_CTS)))
 677                         return 0;
 678                 prev = status;
 679         }
 680
 681         /* NOTREACHED */
 682         return 0;
 683 }
 684
 685 static void oti6858_read_int_callback(struct urb *urb)
 686 {
 687         struct usb_serial_port *port =  urb->context;
 688         struct oti6858_private *priv = usb_get_serial_port_data(port);
 689         int transient = 0, can_recv = 0, resubmit = 1;
 690         int status = urb->status;
 691
 692         switch (status) {
 693         case 0:
 694                 /* success */
 695                 break;
 696         case -ECONNRESET:
 697         case -ENOENT:
 698         case -ESHUTDOWN:
 699                 /* this urb is terminated, clean up */
 700                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n",
 701                         __func__, status);
 702                 return;
 703         default:
 704                 dev_dbg(&urb->dev->dev, "%s(): nonzero urb status received: %d\n",
 705                         __func__, status);
 706                 break;
 707         }
 708
 709         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 710                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 711                 unsigned long flags;
 712
 713                 spin_lock_irqsave(&priv->lock, flags);
 714
 715                 if (!priv->transient) {
 716                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 717                                 if (xs->rx_bytes_avail == 0) {
 718                                         priv->transient = 4;
 719                                         priv->setup_done = 0;
 720                                         resubmit = 0;
 721                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 722                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 723                                 }
 724                         }
 725                 } else {
 726                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 727                                 priv->transient = 0;
 728                         } else if (!priv->setup_done) {
 729                                 resubmit = 0;
 730                         } else if (--priv->transient == 0) {
 731                                 if (xs->rx_bytes_avail == 0) {
 732                                         priv->transient = 4;
 733                                         priv->setup_done = 0;
 734                                         resubmit = 0;
 735                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 736                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 737                                 }
 738                         }
 739                 }
 740
 741                 if (!priv->transient) {
 742                         if (xs->pin_state != priv->status.pin_state)
 743                                 wake_up_interruptible(&port->port.delta_msr_wait);
 744                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 745                 }
 746
 747                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 748                         can_recv = xs->rx_bytes_avail;
 749                         priv->flags.read_urb_in_use = 1;
 750                 }
 751
 752                 transient = priv->transient;
 753                 spin_unlock_irqrestore(&priv->lock, flags);
 754         }
 755
 756         if (can_recv) {
 757                 int result;
 758
 759                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 760                 if (result != 0) {
 761                         priv->flags.read_urb_in_use = 0;
 762                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 763                                         " error %d\n", __func__, result);
 764                 } else {
 765                         resubmit = 0;
 766                 }
 767         } else if (!transient) {
 768                 unsigned long flags;
 769                 int count;
 770
 771                 spin_lock_irqsave(&port->lock, flags);
 772                 count = kfifo_len(&port->write_fifo);
 773                 spin_unlock_irqrestore(&port->lock, flags);
 774
 775                 spin_lock_irqsave(&priv->lock, flags);
 776                 if (priv->flags.write_urb_in_use == 0 && count != 0) {
 777                         schedule_delayed_work(&priv->delayed_write_work, 0);
 778                         resubmit = 0;
 779                 }
 780                 spin_unlock_irqrestore(&priv->lock, flags);
 781         }
 782
 783         if (resubmit) {
 784                 int result;
 785
 786 /*              dev_dbg(&urb->dev->dev, "%s(): submitting interrupt urb\n", __func__); */
 787                 result = usb_submit_urb(urb, GFP_ATOMIC);
 788                 if (result != 0) {
 789                         dev_err(&urb->dev->dev,
 790                                         "%s(): usb_submit_urb() failed with"
 791                                         " error %d\n", __func__, result);
 792                 }
 793         }
 794 }
 795
 796 static void oti6858_read_bulk_callback(struct urb *urb)
 797 {
 798         struct usb_serial_port *port =  urb->context;
 799         struct oti6858_private *priv = usb_get_serial_port_data(port);
 800         unsigned char *data = urb->transfer_buffer;
 801         unsigned long flags;
 802         int status = urb->status;
 803         int result;
 804
 805         spin_lock_irqsave(&priv->lock, flags);
 806         priv->flags.read_urb_in_use = 0;
 807         spin_unlock_irqrestore(&priv->lock, flags);
 808
 809         if (status != 0) {
 810                 dev_dbg(&urb->dev->dev, "%s(): unable to handle the error, exiting\n", __func__);
 811                 return;
 812         }
 813
 814         if (urb->actual_length > 0) {
 815                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 816                 tty_flip_buffer_push(&port->port);
 817         }
 818
 819         /* schedule the interrupt urb */
 820         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 821         if (result != 0 && result != -EPERM) {
 822                 dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 823                                 " error %d\n", __func__, result);
 824         }
 825 }
 826
 827 static void oti6858_write_bulk_callback(struct urb *urb)
 828 {
 829         struct usb_serial_port *port =  urb->context;
 830         struct oti6858_private *priv = usb_get_serial_port_data(port);
 831         int status = urb->status;
 832         int result;
 833
 834         switch (status) {
 835         case 0:
 836                 /* success */
 837                 break;
 838         case -ECONNRESET:
 839         case -ENOENT:
 840         case -ESHUTDOWN:
 841                 /* this urb is terminated, clean up */
 842                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n", __func__, status);
 843                 priv->flags.write_urb_in_use = 0;
 844                 return;
 845         default:
 846                 /* error in the urb, so we have to resubmit it */
 847                 dev_dbg(&urb->dev->dev, "%s(): nonzero write bulk status received: %d\n", __func__, status);
 848                 dev_dbg(&urb->dev->dev, "%s(): overflow in write\n", __func__);
 849
 850                 port->write_urb->transfer_buffer_length = 1;
 851                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 852                 if (result) {
 853                         dev_err_console(port, "%s(): usb_submit_urb() failed,"
 854                                         " error %d\n", __func__, result);
 855                 } else {
 856                         return;
 857                 }
 858         }
 859
 860         priv->flags.write_urb_in_use = 0;
 861
 862         /* schedule the interrupt urb if we are still open */
 863         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 864         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 865         if (result != 0) {
 866                 dev_err(&port->dev, "%s(): failed submitting int urb,"
 867                                         " error %d\n", __func__, result);
 868         }
 869 }
 870
 871 module_usb_serial_driver(serial_drivers, id_table);
 872
 873 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
 874 MODULE_AUTHOR(OTI6858_AUTHOR);
 875 MODULE_LICENSE("GPL");