drivers/usb/serial/oti6858.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Ours Technology Inc. OTi-6858 USB to serial adapter driver.
   4  *
   5  * Copyleft  (C) 2007 Kees Lemmens (adapted for kernel 2.6.20)
   6  * Copyright (C) 2006 Tomasz Michal Lukaszewski (FIXME: add e-mail)
   7  * Copyright (C) 2001-2004 Greg Kroah-Hartman (greg@kroah.com)
   8  * Copyright (C) 2003 IBM Corp.
   9  *
  10  * Many thanks to the authors of pl2303 driver: all functions in this file
  11  * are heavily based on pl2303 code, buffering code is a 1-to-1 copy.
  12  *
  13  * Warning! You use this driver on your own risk! The only official
  14  * description of this device I have is datasheet from manufacturer,
  15  * and it doesn't contain almost any information needed to write a driver.
  16  * Almost all knowlegde used while writing this driver was gathered by:
  17  *  - analyzing traffic between device and the M$ Windows 2000 driver,
  18  *  - trying different bit combinations and checking pin states
  19  *    with a voltmeter,
  20  *  - receiving malformed frames and producing buffer overflows
  21  *    to learn how errors are reported,
  22  * So, THIS CODE CAN DESTROY OTi-6858 AND ANY OTHER DEVICES, THAT ARE
  23  * CONNECTED TO IT!
  24  *
  25  * See Documentation/usb/usb-serial.rst for more information on using this
  26  * driver
  27  *
  28  * TODO:
  29  *  - implement correct flushing for ioctls and oti6858_close()
  30  *  - check how errors (rx overflow, parity error, framing error) are reported
  31  *  - implement oti6858_break_ctl()
  32  *  - implement more ioctls
  33  *  - test/implement flow control
  34  *  - allow setting custom baud rates
  35  */
  36
  37 #include <linux/kernel.h>
  38 #include <linux/errno.h>
  39 #include <linux/slab.h>
  40 #include <linux/tty.h>
  41 #include <linux/tty_driver.h>
  42 #include <linux/tty_flip.h>
  43 #include <linux/serial.h>
  44 #include <linux/module.h>
  45 #include <linux/moduleparam.h>
  46 #include <linux/spinlock.h>
  47 #include <linux/usb.h>
  48 #include <linux/usb/serial.h>
  49 #include <linux/uaccess.h>
  50 #include <linux/kfifo.h>
  51 #include "oti6858.h"
  52
  53 #define OTI6858_DESCRIPTION \
  54         "Ours Technology Inc. OTi-6858 USB to serial adapter driver"
  55 #define OTI6858_AUTHOR "Tomasz Michal Lukaszewski <FIXME@FIXME>"
  56
  57 static const struct usb_device_id id_table[] = {
  58         { USB_DEVICE(OTI6858_VENDOR_ID, OTI6858_PRODUCT_ID) },
  59         { }
  60 };
  61
  62 MODULE_DEVICE_TABLE(usb, id_table);
  63
  64 /* requests */
  65 #define OTI6858_REQ_GET_STATUS          (USB_DIR_IN | USB_TYPE_VENDOR | 0x00)
  66 #define OTI6858_REQ_T_GET_STATUS        0x01
  67
  68 #define OTI6858_REQ_SET_LINE            (USB_DIR_OUT | USB_TYPE_VENDOR | 0x00)
  69 #define OTI6858_REQ_T_SET_LINE          0x00
  70
  71 #define OTI6858_REQ_CHECK_TXBUFF        (USB_DIR_IN | USB_TYPE_VENDOR | 0x01)
  72 #define OTI6858_REQ_T_CHECK_TXBUFF      0x00
  73
  74 /* format of the control packet */
  75 struct oti6858_control_pkt {
  76         __le16  divisor;        /* baud rate = 96000000 / (16 * divisor), LE */
  77 #define OTI6858_MAX_BAUD_RATE   3000000
  78         u8      frame_fmt;
  79 #define FMT_STOP_BITS_MASK      0xc0
  80 #define FMT_STOP_BITS_1         0x00
  81 #define FMT_STOP_BITS_2         0x40    /* 1.5 stop bits if FMT_DATA_BITS_5 */
  82 #define FMT_PARITY_MASK         0x38
  83 #define FMT_PARITY_NONE         0x00
  84 #define FMT_PARITY_ODD          0x08
  85 #define FMT_PARITY_EVEN         0x18
  86 #define FMT_PARITY_MARK         0x28
  87 #define FMT_PARITY_SPACE        0x38
  88 #define FMT_DATA_BITS_MASK      0x03
  89 #define FMT_DATA_BITS_5         0x00
  90 #define FMT_DATA_BITS_6         0x01
  91 #define FMT_DATA_BITS_7         0x02
  92 #define FMT_DATA_BITS_8         0x03
  93         u8      something;      /* always equals 0x43 */
  94         u8      control;        /* settings of flow control lines */
  95 #define CONTROL_MASK            0x0c
  96 #define CONTROL_DTR_HIGH        0x08
  97 #define CONTROL_RTS_HIGH        0x04
  98         u8      tx_status;
  99 #define TX_BUFFER_EMPTIED       0x09
 100         u8      pin_state;
 101 #define PIN_MASK                0x3f
 102 #define PIN_MSR_MASK            0x1b
 103 #define PIN_RTS                 0x20    /* output pin */
 104 #define PIN_CTS                 0x10    /* input pin, active low */
 105 #define PIN_DSR                 0x08    /* input pin, active low */
 106 #define PIN_DTR                 0x04    /* output pin */
 107 #define PIN_RI                  0x02    /* input pin, active low */
 108 #define PIN_DCD                 0x01    /* input pin, active low */
 109         u8      rx_bytes_avail;         /* number of bytes in rx buffer */;
 110 };
 111
 112 #define OTI6858_CTRL_PKT_SIZE   sizeof(struct oti6858_control_pkt)
 113 #define OTI6858_CTRL_EQUALS_PENDING(a, priv) \
 114         (((a)->divisor == (priv)->pending_setup.divisor) \
 115           && ((a)->control == (priv)->pending_setup.control) \
 116           && ((a)->frame_fmt == (priv)->pending_setup.frame_fmt))
 117
 118 /* function prototypes */
 119 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port);
 120 static void oti6858_close(struct usb_serial_port *port);
 121 static void oti6858_set_termios(struct tty_struct *tty,
 122                         struct usb_serial_port *port, struct ktermios *old);
 123 static void oti6858_init_termios(struct tty_struct *tty);
 124 static void oti6858_read_int_callback(struct urb *urb);
 125 static void oti6858_read_bulk_callback(struct urb *urb);
 126 static void oti6858_write_bulk_callback(struct urb *urb);
 127 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 128                         const unsigned char *buf, int count);
 129 static int oti6858_write_room(struct tty_struct *tty);
 130 static int oti6858_chars_in_buffer(struct tty_struct *tty);
 131 static int oti6858_tiocmget(struct tty_struct *tty);
 132 static int oti6858_tiocmset(struct tty_struct *tty,
 133                                 unsigned int set, unsigned int clear);
 134 static int oti6858_port_probe(struct usb_serial_port *port);
 135 static int oti6858_port_remove(struct usb_serial_port *port);
 136
 137 /* device info */
 138 static struct usb_serial_driver oti6858_device = {
 139         .driver = {
 140                 .owner =        THIS_MODULE,
 141                 .name =         "oti6858",
 142         },
 143         .id_table =             id_table,
 144         .num_ports =            1,
 145         .num_bulk_in =          1,
 146         .num_bulk_out =         1,
 147         .num_interrupt_in =     1,
 148         .open =                 oti6858_open,
 149         .close =                oti6858_close,
 150         .write =                oti6858_write,
 151         .set_termios =          oti6858_set_termios,
 152         .init_termios =         oti6858_init_termios,
 153         .tiocmget =             oti6858_tiocmget,
 154         .tiocmset =             oti6858_tiocmset,
 155         .tiocmiwait =           usb_serial_generic_tiocmiwait,
 156         .read_bulk_callback =   oti6858_read_bulk_callback,
 157         .read_int_callback =    oti6858_read_int_callback,
 158         .write_bulk_callback =  oti6858_write_bulk_callback,
 159         .write_room =           oti6858_write_room,
 160         .chars_in_buffer =      oti6858_chars_in_buffer,
 161         .port_probe =           oti6858_port_probe,
 162         .port_remove =          oti6858_port_remove,
 163 };
 164
 165 static struct usb_serial_driver * const serial_drivers[] = {
 166         &oti6858_device, NULL
 167 };
 168
 169 struct oti6858_private {
 170         spinlock_t lock;
 171
 172         struct oti6858_control_pkt status;
 173
 174         struct {
 175                 u8 read_urb_in_use;
 176                 u8 write_urb_in_use;
 177         } flags;
 178         struct delayed_work delayed_write_work;
 179
 180         struct {
 181                 __le16 divisor;
 182                 u8 frame_fmt;
 183                 u8 control;
 184         } pending_setup;
 185         u8 transient;
 186         u8 setup_done;
 187         struct delayed_work delayed_setup_work;
 188
 189         struct usb_serial_port *port;   /* USB port with which associated */
 190 };
 191
 192 static void setup_line(struct work_struct *work)
 193 {
 194         struct oti6858_private *priv = container_of(work,
 195                         struct oti6858_private, delayed_setup_work.work);
 196         struct usb_serial_port *port = priv->port;
 197         struct oti6858_control_pkt *new_setup;
 198         unsigned long flags;
 199         int result;
 200
 201         new_setup = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 202         if (!new_setup) {
 203                 /* we will try again */
 204                 schedule_delayed_work(&priv->delayed_setup_work,
 205                                                 msecs_to_jiffies(2));
 206                 return;
 207         }
 208
 209         result = usb_control_msg(port->serial->dev,
 210                                 usb_rcvctrlpipe(port->serial->dev, 0),
 211                                 OTI6858_REQ_T_GET_STATUS,
 212                                 OTI6858_REQ_GET_STATUS,
 213                                 0, 0,
 214                                 new_setup, OTI6858_CTRL_PKT_SIZE,
 215                                 100);
 216
 217         if (result != OTI6858_CTRL_PKT_SIZE) {
 218                 dev_err(&port->dev, "%s(): error reading status\n", __func__);
 219                 kfree(new_setup);
 220                 /* we will try again */
 221                 schedule_delayed_work(&priv->delayed_setup_work,
 222                                                         msecs_to_jiffies(2));
 223                 return;
 224         }
 225
 226         spin_lock_irqsave(&priv->lock, flags);
 227         if (!OTI6858_CTRL_EQUALS_PENDING(new_setup, priv)) {
 228                 new_setup->divisor = priv->pending_setup.divisor;
 229                 new_setup->control = priv->pending_setup.control;
 230                 new_setup->frame_fmt = priv->pending_setup.frame_fmt;
 231
 232                 spin_unlock_irqrestore(&priv->lock, flags);
 233                 result = usb_control_msg(port->serial->dev,
 234                                         usb_sndctrlpipe(port->serial->dev, 0),
 235                                         OTI6858_REQ_T_SET_LINE,
 236                                         OTI6858_REQ_SET_LINE,
 237                                         0, 0,
 238                                         new_setup, OTI6858_CTRL_PKT_SIZE,
 239                                         100);
 240         } else {
 241                 spin_unlock_irqrestore(&priv->lock, flags);
 242                 result = 0;
 243         }
 244         kfree(new_setup);
 245
 246         spin_lock_irqsave(&priv->lock, flags);
 247         if (result != OTI6858_CTRL_PKT_SIZE)
 248                 priv->transient = 0;
 249         priv->setup_done = 1;
 250         spin_unlock_irqrestore(&priv->lock, flags);
 251
 252         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 253         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 254         if (result != 0) {
 255                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 256                         __func__, result);
 257         }
 258 }
 259
 260 static void send_data(struct work_struct *work)
 261 {
 262         struct oti6858_private *priv = container_of(work,
 263                         struct oti6858_private, delayed_write_work.work);
 264         struct usb_serial_port *port = priv->port;
 265         int count = 0, result;
 266         unsigned long flags;
 267         u8 *allow;
 268
 269         spin_lock_irqsave(&priv->lock, flags);
 270         if (priv->flags.write_urb_in_use) {
 271                 spin_unlock_irqrestore(&priv->lock, flags);
 272                 schedule_delayed_work(&priv->delayed_write_work,
 273                                                 msecs_to_jiffies(2));
 274                 return;
 275         }
 276         priv->flags.write_urb_in_use = 1;
 277         spin_unlock_irqrestore(&priv->lock, flags);
 278
 279         spin_lock_irqsave(&port->lock, flags);
 280         count = kfifo_len(&port->write_fifo);
 281         spin_unlock_irqrestore(&port->lock, flags);
 282
 283         if (count > port->bulk_out_size)
 284                 count = port->bulk_out_size;
 285
 286         if (count != 0) {
 287                 allow = kmalloc(1, GFP_KERNEL);
 288                 if (!allow)
 289                         return;
 290
 291                 result = usb_control_msg(port->serial->dev,
 292                                 usb_rcvctrlpipe(port->serial->dev, 0),
 293                                 OTI6858_REQ_T_CHECK_TXBUFF,
 294                                 OTI6858_REQ_CHECK_TXBUFF,
 295                                 count, 0, allow, 1, 100);
 296                 if (result != 1 || *allow != 0)
 297                         count = 0;
 298                 kfree(allow);
 299         }
 300
 301         if (count == 0) {
 302                 priv->flags.write_urb_in_use = 0;
 303
 304                 dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 305                 result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
 306                 if (result != 0) {
 307                         dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 308                                 __func__, result);
 309                 }
 310                 return;
 311         }
 312
 313         count = kfifo_out_locked(&port->write_fifo,
 314                                         port->write_urb->transfer_buffer,
 315                                         count, &port->lock);
 316         port->write_urb->transfer_buffer_length = count;
 317         result = usb_submit_urb(port->write_urb, GFP_NOIO);
 318         if (result != 0) {
 319                 dev_err_console(port, "%s(): usb_submit_urb() failed with error %d\n",
 320                                 __func__, result);
 321                 priv->flags.write_urb_in_use = 0;
 322         }
 323
 324         usb_serial_port_softint(port);
 325 }
 326
 327 static int oti6858_port_probe(struct usb_serial_port *port)
 328 {
 329         struct oti6858_private *priv;
 330
 331         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 332         if (!priv)
 333                 return -ENOMEM;
 334
 335         spin_lock_init(&priv->lock);
 336         priv->port = port;
 337         INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 338         INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 339
 340         usb_set_serial_port_data(port, priv);
 341
 342         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 343
 344         return 0;
 345 }
 346
 347 static int oti6858_port_remove(struct usb_serial_port *port)
 348 {
 349         struct oti6858_private *priv;
 350
 351         priv = usb_get_serial_port_data(port);
 352         kfree(priv);
 353
 354         return 0;
 355 }
 356
 357 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 358                         const unsigned char *buf, int count)
 359 {
 360         if (!count)
 361                 return count;
 362
 363         count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
 364
 365         return count;
 366 }
 367
 368 static int oti6858_write_room(struct tty_struct *tty)
 369 {
 370         struct usb_serial_port *port = tty->driver_data;
 371         int room = 0;
 372         unsigned long flags;
 373
 374         spin_lock_irqsave(&port->lock, flags);
 375         room = kfifo_avail(&port->write_fifo);
 376         spin_unlock_irqrestore(&port->lock, flags);
 377
 378         return room;
 379 }
 380
 381 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 382 {
 383         struct usb_serial_port *port = tty->driver_data;
 384         int chars = 0;
 385         unsigned long flags;
 386
 387         spin_lock_irqsave(&port->lock, flags);
 388         chars = kfifo_len(&port->write_fifo);
 389         spin_unlock_irqrestore(&port->lock, flags);
 390
 391         return chars;
 392 }
 393
 394 static void oti6858_init_termios(struct tty_struct *tty)
 395 {
 396         tty_encode_baud_rate(tty, 38400, 38400);
 397 }
 398
 399 static void oti6858_set_termios(struct tty_struct *tty,
 400                 struct usb_serial_port *port, struct ktermios *old_termios)
 401 {
 402         struct oti6858_private *priv = usb_get_serial_port_data(port);
 403         unsigned long flags;
 404         unsigned int cflag;
 405         u8 frame_fmt, control;
 406         __le16 divisor;
 407         int br;
 408
 409         cflag = tty->termios.c_cflag;
 410
 411         spin_lock_irqsave(&priv->lock, flags);
 412         divisor = priv->pending_setup.divisor;
 413         frame_fmt = priv->pending_setup.frame_fmt;
 414         control = priv->pending_setup.control;
 415         spin_unlock_irqrestore(&priv->lock, flags);
 416
 417         frame_fmt &= ~FMT_DATA_BITS_MASK;
 418         switch (cflag & CSIZE) {
 419         case CS5:
 420                 frame_fmt |= FMT_DATA_BITS_5;
 421                 break;
 422         case CS6:
 423                 frame_fmt |= FMT_DATA_BITS_6;
 424                 break;
 425         case CS7:
 426                 frame_fmt |= FMT_DATA_BITS_7;
 427                 break;
 428         default:
 429         case CS8:
 430                 frame_fmt |= FMT_DATA_BITS_8;
 431                 break;
 432         }
 433
 434         /* manufacturer claims that this device can work with baud rates
 435          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 436          * guarantee that any other baud rate will work (especially
 437          * the higher ones)
 438          */
 439         br = tty_get_baud_rate(tty);
 440         if (br == 0) {
 441                 divisor = 0;
 442         } else {
 443                 int real_br;
 444                 int new_divisor;
 445                 br = min(br, OTI6858_MAX_BAUD_RATE);
 446
 447                 new_divisor = (96000000 + 8 * br) / (16 * br);
 448                 real_br = 96000000 / (16 * new_divisor);
 449                 divisor = cpu_to_le16(new_divisor);
 450                 tty_encode_baud_rate(tty, real_br, real_br);
 451         }
 452
 453         frame_fmt &= ~FMT_STOP_BITS_MASK;
 454         if ((cflag & CSTOPB) != 0)
 455                 frame_fmt |= FMT_STOP_BITS_2;
 456         else
 457                 frame_fmt |= FMT_STOP_BITS_1;
 458
 459         frame_fmt &= ~FMT_PARITY_MASK;
 460         if ((cflag & PARENB) != 0) {
 461                 if ((cflag & PARODD) != 0)
 462                         frame_fmt |= FMT_PARITY_ODD;
 463                 else
 464                         frame_fmt |= FMT_PARITY_EVEN;
 465         } else {
 466                 frame_fmt |= FMT_PARITY_NONE;
 467         }
 468
 469         control &= ~CONTROL_MASK;
 470         if ((cflag & CRTSCTS) != 0)
 471                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 472
 473         /* change control lines if we are switching to or from B0 */
 474         /* FIXME:
 475         spin_lock_irqsave(&priv->lock, flags);
 476         control = priv->line_control;
 477         if ((cflag & CBAUD) == B0)
 478                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 479         else
 480                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 481         if (control != priv->line_control) {
 482                 control = priv->line_control;
 483                 spin_unlock_irqrestore(&priv->lock, flags);
 484                 set_control_lines(serial->dev, control);
 485         } else {
 486                 spin_unlock_irqrestore(&priv->lock, flags);
 487         }
 488         */
 489
 490         spin_lock_irqsave(&priv->lock, flags);
 491         if (divisor != priv->pending_setup.divisor
 492                         || control != priv->pending_setup.control
 493                         || frame_fmt != priv->pending_setup.frame_fmt) {
 494                 priv->pending_setup.divisor = divisor;
 495                 priv->pending_setup.control = control;
 496                 priv->pending_setup.frame_fmt = frame_fmt;
 497         }
 498         spin_unlock_irqrestore(&priv->lock, flags);
 499 }
 500
 501 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
 502 {
 503         struct oti6858_private *priv = usb_get_serial_port_data(port);
 504         struct usb_serial *serial = port->serial;
 505         struct oti6858_control_pkt *buf;
 506         unsigned long flags;
 507         int result;
 508
 509         usb_clear_halt(serial->dev, port->write_urb->pipe);
 510         usb_clear_halt(serial->dev, port->read_urb->pipe);
 511
 512         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 513         if (!buf)
 514                 return -ENOMEM;
 515
 516         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 517                                 OTI6858_REQ_T_GET_STATUS,
 518                                 OTI6858_REQ_GET_STATUS,
 519                                 0, 0,
 520                                 buf, OTI6858_CTRL_PKT_SIZE,
 521                                 100);
 522         if (result != OTI6858_CTRL_PKT_SIZE) {
 523                 /* assume default (after power-on reset) values */
 524                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 525                 buf->frame_fmt = 0x03;  /* 8N1 */
 526                 buf->something = 0x43;
 527                 buf->control = 0x4c;    /* DTR, RTS */
 528                 buf->tx_status = 0x00;
 529                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 530                 buf->rx_bytes_avail = 0x00;
 531         }
 532
 533         spin_lock_irqsave(&priv->lock, flags);
 534         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 535         priv->pending_setup.divisor = buf->divisor;
 536         priv->pending_setup.frame_fmt = buf->frame_fmt;
 537         priv->pending_setup.control = buf->control;
 538         spin_unlock_irqrestore(&priv->lock, flags);
 539         kfree(buf);
 540
 541         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 542         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 543         if (result != 0) {
 544                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 545                         __func__, result);
 546                 oti6858_close(port);
 547                 return result;
 548         }
 549
 550         /* setup termios */
 551         if (tty)
 552                 oti6858_set_termios(tty, port, NULL);
 553
 554         return 0;
 555 }
 556
 557 static void oti6858_close(struct usb_serial_port *port)
 558 {
 559         struct oti6858_private *priv = usb_get_serial_port_data(port);
 560         unsigned long flags;
 561
 562         spin_lock_irqsave(&port->lock, flags);
 563         /* clear out any remaining data in the buffer */
 564         kfifo_reset_out(&port->write_fifo);
 565         spin_unlock_irqrestore(&port->lock, flags);
 566
 567         dev_dbg(&port->dev, "%s(): after buf_clear()\n", __func__);
 568
 569         /* cancel scheduled setup */
 570         cancel_delayed_work_sync(&priv->delayed_setup_work);
 571         cancel_delayed_work_sync(&priv->delayed_write_work);
 572
 573         /* shutdown our urbs */
 574         dev_dbg(&port->dev, "%s(): shutting down urbs\n", __func__);
 575         usb_kill_urb(port->write_urb);
 576         usb_kill_urb(port->read_urb);
 577         usb_kill_urb(port->interrupt_in_urb);
 578 }
 579
 580 static int oti6858_tiocmset(struct tty_struct *tty,
 581                                 unsigned int set, unsigned int clear)
 582 {
 583         struct usb_serial_port *port = tty->driver_data;
 584         struct oti6858_private *priv = usb_get_serial_port_data(port);
 585         unsigned long flags;
 586         u8 control;
 587
 588         dev_dbg(&port->dev, "%s(set = 0x%08x, clear = 0x%08x)\n",
 589                 __func__, set, clear);
 590
 591         /* FIXME: check if this is correct (active high/low) */
 592         spin_lock_irqsave(&priv->lock, flags);
 593         control = priv->pending_setup.control;
 594         if ((set & TIOCM_RTS) != 0)
 595                 control |= CONTROL_RTS_HIGH;
 596         if ((set & TIOCM_DTR) != 0)
 597                 control |= CONTROL_DTR_HIGH;
 598         if ((clear & TIOCM_RTS) != 0)
 599                 control &= ~CONTROL_RTS_HIGH;
 600         if ((clear & TIOCM_DTR) != 0)
 601                 control &= ~CONTROL_DTR_HIGH;
 602
 603         if (control != priv->pending_setup.control)
 604                 priv->pending_setup.control = control;
 605
 606         spin_unlock_irqrestore(&priv->lock, flags);
 607         return 0;
 608 }
 609
 610 static int oti6858_tiocmget(struct tty_struct *tty)
 611 {
 612         struct usb_serial_port *port = tty->driver_data;
 613         struct oti6858_private *priv = usb_get_serial_port_data(port);
 614         unsigned long flags;
 615         unsigned pin_state;
 616         unsigned result = 0;
 617
 618         spin_lock_irqsave(&priv->lock, flags);
 619         pin_state = priv->status.pin_state & PIN_MASK;
 620         spin_unlock_irqrestore(&priv->lock, flags);
 621
 622         /* FIXME: check if this is correct (active high/low) */
 623         if ((pin_state & PIN_RTS) != 0)
 624                 result |= TIOCM_RTS;
 625         if ((pin_state & PIN_CTS) != 0)
 626                 result |= TIOCM_CTS;
 627         if ((pin_state & PIN_DSR) != 0)
 628                 result |= TIOCM_DSR;
 629         if ((pin_state & PIN_DTR) != 0)
 630                 result |= TIOCM_DTR;
 631         if ((pin_state & PIN_RI) != 0)
 632                 result |= TIOCM_RI;
 633         if ((pin_state & PIN_DCD) != 0)
 634                 result |= TIOCM_CD;
 635
 636         dev_dbg(&port->dev, "%s() = 0x%08x\n", __func__, result);
 637
 638         return result;
 639 }
 640
 641 static void oti6858_read_int_callback(struct urb *urb)
 642 {
 643         struct usb_serial_port *port =  urb->context;
 644         struct oti6858_private *priv = usb_get_serial_port_data(port);
 645         int transient = 0, can_recv = 0, resubmit = 1;
 646         int status = urb->status;
 647
 648         switch (status) {
 649         case 0:
 650                 /* success */
 651                 break;
 652         case -ECONNRESET:
 653         case -ENOENT:
 654         case -ESHUTDOWN:
 655                 /* this urb is terminated, clean up */
 656                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n",
 657                         __func__, status);
 658                 return;
 659         default:
 660                 dev_dbg(&urb->dev->dev, "%s(): nonzero urb status received: %d\n",
 661                         __func__, status);
 662                 break;
 663         }
 664
 665         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 666                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 667                 unsigned long flags;
 668
 669                 spin_lock_irqsave(&priv->lock, flags);
 670
 671                 if (!priv->transient) {
 672                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 673                                 if (xs->rx_bytes_avail == 0) {
 674                                         priv->transient = 4;
 675                                         priv->setup_done = 0;
 676                                         resubmit = 0;
 677                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 678                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 679                                 }
 680                         }
 681                 } else {
 682                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 683                                 priv->transient = 0;
 684                         } else if (!priv->setup_done) {
 685                                 resubmit = 0;
 686                         } else if (--priv->transient == 0) {
 687                                 if (xs->rx_bytes_avail == 0) {
 688                                         priv->transient = 4;
 689                                         priv->setup_done = 0;
 690                                         resubmit = 0;
 691                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 692                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 693                                 }
 694                         }
 695                 }
 696
 697                 if (!priv->transient) {
 698                         u8 delta = xs->pin_state ^ priv->status.pin_state;
 699
 700                         if (delta & PIN_MSR_MASK) {
 701                                 if (delta & PIN_CTS)
 702                                         port->icount.cts++;
 703                                 if (delta & PIN_DSR)
 704                                         port->icount.dsr++;
 705                                 if (delta & PIN_RI)
 706                                         port->icount.rng++;
 707                                 if (delta & PIN_DCD)
 708                                         port->icount.dcd++;
 709
 710                                 wake_up_interruptible(&port->port.delta_msr_wait);
 711                         }
 712
 713                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 714                 }
 715
 716                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 717                         can_recv = xs->rx_bytes_avail;
 718                         priv->flags.read_urb_in_use = 1;
 719                 }
 720
 721                 transient = priv->transient;
 722                 spin_unlock_irqrestore(&priv->lock, flags);
 723         }
 724
 725         if (can_recv) {
 726                 int result;
 727
 728                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 729                 if (result != 0) {
 730                         priv->flags.read_urb_in_use = 0;
 731                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 732                                         " error %d\n", __func__, result);
 733                 } else {
 734                         resubmit = 0;
 735                 }
 736         } else if (!transient) {
 737                 unsigned long flags;
 738                 int count;
 739
 740                 spin_lock_irqsave(&port->lock, flags);
 741                 count = kfifo_len(&port->write_fifo);
 742                 spin_unlock_irqrestore(&port->lock, flags);
 743
 744                 spin_lock_irqsave(&priv->lock, flags);
 745                 if (priv->flags.write_urb_in_use == 0 && count != 0) {
 746                         schedule_delayed_work(&priv->delayed_write_work, 0);
 747                         resubmit = 0;
 748                 }
 749                 spin_unlock_irqrestore(&priv->lock, flags);
 750         }
 751
 752         if (resubmit) {
 753                 int result;
 754
 755 /*              dev_dbg(&urb->dev->dev, "%s(): submitting interrupt urb\n", __func__); */
 756                 result = usb_submit_urb(urb, GFP_ATOMIC);
 757                 if (result != 0) {
 758                         dev_err(&urb->dev->dev,
 759                                         "%s(): usb_submit_urb() failed with"
 760                                         " error %d\n", __func__, result);
 761                 }
 762         }
 763 }
 764
 765 static void oti6858_read_bulk_callback(struct urb *urb)
 766 {
 767         struct usb_serial_port *port =  urb->context;
 768         struct oti6858_private *priv = usb_get_serial_port_data(port);
 769         unsigned char *data = urb->transfer_buffer;
 770         unsigned long flags;
 771         int status = urb->status;
 772         int result;
 773
 774         spin_lock_irqsave(&priv->lock, flags);
 775         priv->flags.read_urb_in_use = 0;
 776         spin_unlock_irqrestore(&priv->lock, flags);
 777
 778         if (status != 0) {
 779                 dev_dbg(&urb->dev->dev, "%s(): unable to handle the error, exiting\n", __func__);
 780                 return;
 781         }
 782
 783         if (urb->actual_length > 0) {
 784                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 785                 tty_flip_buffer_push(&port->port);
 786         }
 787
 788         /* schedule the interrupt urb */
 789         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 790         if (result != 0 && result != -EPERM) {
 791                 dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 792                                 " error %d\n", __func__, result);
 793         }
 794 }
 795
 796 static void oti6858_write_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         int status = urb->status;
 801         int result;
 802
 803         switch (status) {
 804         case 0:
 805                 /* success */
 806                 break;
 807         case -ECONNRESET:
 808         case -ENOENT:
 809         case -ESHUTDOWN:
 810                 /* this urb is terminated, clean up */
 811                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n", __func__, status);
 812                 priv->flags.write_urb_in_use = 0;
 813                 return;
 814         default:
 815                 /* error in the urb, so we have to resubmit it */
 816                 dev_dbg(&urb->dev->dev, "%s(): nonzero write bulk status received: %d\n", __func__, status);
 817                 dev_dbg(&urb->dev->dev, "%s(): overflow in write\n", __func__);
 818
 819                 port->write_urb->transfer_buffer_length = 1;
 820                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 821                 if (result) {
 822                         dev_err_console(port, "%s(): usb_submit_urb() failed,"
 823                                         " error %d\n", __func__, result);
 824                 } else {
 825                         return;
 826                 }
 827         }
 828
 829         priv->flags.write_urb_in_use = 0;
 830
 831         /* schedule the interrupt urb if we are still open */
 832         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 833         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 834         if (result != 0) {
 835                 dev_err(&port->dev, "%s(): failed submitting int urb,"
 836                                         " error %d\n", __func__, result);
 837         }
 838 }
 839
 840 module_usb_serial_driver(serial_drivers, id_table);
 841
 842 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
 843 MODULE_AUTHOR(OTI6858_AUTHOR);
 844 MODULE_LICENSE("GPL v2");