kernel/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/slab.h>
  43 #include <linux/tty.h>
  44 #include <linux/tty_driver.h>
  45 #include <linux/tty_flip.h>
  46 #include <linux/serial.h>
  47 #include <linux/module.h>
  48 #include <linux/moduleparam.h>
  49 #include <linux/spinlock.h>
  50 #include <linux/usb.h>
  51 #include <linux/usb/serial.h>
  52 #include <linux/uaccess.h>
  53 #include <linux/kfifo.h>
  54 #include "oti6858.h"
  55
  56 #define OTI6858_DESCRIPTION \
  57         "Ours Technology Inc. OTi-6858 USB to serial adapter driver"
  58 #define OTI6858_AUTHOR "Tomasz Michal Lukaszewski <FIXME@FIXME>"
  59
  60 static const struct usb_device_id id_table[] = {
  61         { USB_DEVICE(OTI6858_VENDOR_ID, OTI6858_PRODUCT_ID) },
  62         { }
  63 };
  64
  65 MODULE_DEVICE_TABLE(usb, id_table);
  66
  67 /* requests */
  68 #define OTI6858_REQ_GET_STATUS          (USB_DIR_IN | USB_TYPE_VENDOR | 0x00)
  69 #define OTI6858_REQ_T_GET_STATUS        0x01
  70
  71 #define OTI6858_REQ_SET_LINE            (USB_DIR_OUT | USB_TYPE_VENDOR | 0x00)
  72 #define OTI6858_REQ_T_SET_LINE          0x00
  73
  74 #define OTI6858_REQ_CHECK_TXBUFF        (USB_DIR_IN | USB_TYPE_VENDOR | 0x01)
  75 #define OTI6858_REQ_T_CHECK_TXBUFF      0x00
  76
  77 /* format of the control packet */
  78 struct oti6858_control_pkt {
  79         __le16  divisor;        /* baud rate = 96000000 / (16 * divisor), LE */
  80 #define OTI6858_MAX_BAUD_RATE   3000000
  81         u8      frame_fmt;
  82 #define FMT_STOP_BITS_MASK      0xc0
  83 #define FMT_STOP_BITS_1         0x00
  84 #define FMT_STOP_BITS_2         0x40    /* 1.5 stop bits if FMT_DATA_BITS_5 */
  85 #define FMT_PARITY_MASK         0x38
  86 #define FMT_PARITY_NONE         0x00
  87 #define FMT_PARITY_ODD          0x08
  88 #define FMT_PARITY_EVEN         0x18
  89 #define FMT_PARITY_MARK         0x28
  90 #define FMT_PARITY_SPACE        0x38
  91 #define FMT_DATA_BITS_MASK      0x03
  92 #define FMT_DATA_BITS_5         0x00
  93 #define FMT_DATA_BITS_6         0x01
  94 #define FMT_DATA_BITS_7         0x02
  95 #define FMT_DATA_BITS_8         0x03
  96         u8      something;      /* always equals 0x43 */
  97         u8      control;        /* settings of flow control lines */
  98 #define CONTROL_MASK            0x0c
  99 #define CONTROL_DTR_HIGH        0x08
 100 #define CONTROL_RTS_HIGH        0x04
 101         u8      tx_status;
 102 #define TX_BUFFER_EMPTIED       0x09
 103         u8      pin_state;
 104 #define PIN_MASK                0x3f
 105 #define PIN_MSR_MASK            0x1b
 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_attach(struct usb_serial *serial);
 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 =           usb_serial_generic_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         .attach =               oti6858_attach,
 163         .port_probe =           oti6858_port_probe,
 164         .port_remove =          oti6858_port_remove,
 165 };
 166
 167 static struct usb_serial_driver * const serial_drivers[] = {
 168         &oti6858_device, NULL
 169 };
 170
 171 struct oti6858_private {
 172         spinlock_t lock;
 173
 174         struct oti6858_control_pkt status;
 175
 176         struct {
 177                 u8 read_urb_in_use;
 178                 u8 write_urb_in_use;
 179         } flags;
 180         struct delayed_work delayed_write_work;
 181
 182         struct {
 183                 __le16 divisor;
 184                 u8 frame_fmt;
 185                 u8 control;
 186         } pending_setup;
 187         u8 transient;
 188         u8 setup_done;
 189         struct delayed_work delayed_setup_work;
 190
 191         struct usb_serial_port *port;   /* USB port with which associated */
 192 };
 193
 194 static void setup_line(struct work_struct *work)
 195 {
 196         struct oti6858_private *priv = container_of(work,
 197                         struct oti6858_private, delayed_setup_work.work);
 198         struct usb_serial_port *port = priv->port;
 199         struct oti6858_control_pkt *new_setup;
 200         unsigned long flags;
 201         int result;
 202
 203         new_setup = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 204         if (!new_setup) {
 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                         return;
 292
 293                 result = usb_control_msg(port->serial->dev,
 294                                 usb_rcvctrlpipe(port->serial->dev, 0),
 295                                 OTI6858_REQ_T_CHECK_TXBUFF,
 296                                 OTI6858_REQ_CHECK_TXBUFF,
 297                                 count, 0, allow, 1, 100);
 298                 if (result != 1 || *allow != 0)
 299                         count = 0;
 300                 kfree(allow);
 301         }
 302
 303         if (count == 0) {
 304                 priv->flags.write_urb_in_use = 0;
 305
 306                 dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 307                 result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
 308                 if (result != 0) {
 309                         dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 310                                 __func__, result);
 311                 }
 312                 return;
 313         }
 314
 315         count = kfifo_out_locked(&port->write_fifo,
 316                                         port->write_urb->transfer_buffer,
 317                                         count, &port->lock);
 318         port->write_urb->transfer_buffer_length = count;
 319         result = usb_submit_urb(port->write_urb, GFP_NOIO);
 320         if (result != 0) {
 321                 dev_err_console(port, "%s(): usb_submit_urb() failed with error %d\n",
 322                                 __func__, result);
 323                 priv->flags.write_urb_in_use = 0;
 324         }
 325
 326         usb_serial_port_softint(port);
 327 }
 328
 329 static int oti6858_attach(struct usb_serial *serial)
 330 {
 331         unsigned char num_ports = serial->num_ports;
 332
 333         if (serial->num_bulk_in < num_ports ||
 334                         serial->num_bulk_out < num_ports ||
 335                         serial->num_interrupt_in < num_ports) {
 336                 dev_err(&serial->interface->dev, "missing endpoints\n");
 337                 return -ENODEV;
 338         }
 339
 340         return 0;
 341 }
 342
 343 static int oti6858_port_probe(struct usb_serial_port *port)
 344 {
 345         struct oti6858_private *priv;
 346
 347         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 348         if (!priv)
 349                 return -ENOMEM;
 350
 351         spin_lock_init(&priv->lock);
 352         priv->port = port;
 353         INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 354         INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 355
 356         usb_set_serial_port_data(port, priv);
 357
 358         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 359
 360         return 0;
 361 }
 362
 363 static int oti6858_port_remove(struct usb_serial_port *port)
 364 {
 365         struct oti6858_private *priv;
 366
 367         priv = usb_get_serial_port_data(port);
 368         kfree(priv);
 369
 370         return 0;
 371 }
 372
 373 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 374                         const unsigned char *buf, int count)
 375 {
 376         if (!count)
 377                 return count;
 378
 379         count = kfifo_in_locked(&port->write_fifo, buf, count, &port->lock);
 380
 381         return count;
 382 }
 383
 384 static int oti6858_write_room(struct tty_struct *tty)
 385 {
 386         struct usb_serial_port *port = tty->driver_data;
 387         int room = 0;
 388         unsigned long flags;
 389
 390         spin_lock_irqsave(&port->lock, flags);
 391         room = kfifo_avail(&port->write_fifo);
 392         spin_unlock_irqrestore(&port->lock, flags);
 393
 394         return room;
 395 }
 396
 397 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 398 {
 399         struct usb_serial_port *port = tty->driver_data;
 400         int chars = 0;
 401         unsigned long flags;
 402
 403         spin_lock_irqsave(&port->lock, flags);
 404         chars = kfifo_len(&port->write_fifo);
 405         spin_unlock_irqrestore(&port->lock, flags);
 406
 407         return chars;
 408 }
 409
 410 static void oti6858_init_termios(struct tty_struct *tty)
 411 {
 412         tty->termios = tty_std_termios;
 413         tty->termios.c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
 414         tty->termios.c_ispeed = 38400;
 415         tty->termios.c_ospeed = 38400;
 416 }
 417
 418 static void oti6858_set_termios(struct tty_struct *tty,
 419                 struct usb_serial_port *port, struct ktermios *old_termios)
 420 {
 421         struct oti6858_private *priv = usb_get_serial_port_data(port);
 422         unsigned long flags;
 423         unsigned int cflag;
 424         u8 frame_fmt, control;
 425         __le16 divisor;
 426         int br;
 427
 428         cflag = tty->termios.c_cflag;
 429
 430         spin_lock_irqsave(&priv->lock, flags);
 431         divisor = priv->pending_setup.divisor;
 432         frame_fmt = priv->pending_setup.frame_fmt;
 433         control = priv->pending_setup.control;
 434         spin_unlock_irqrestore(&priv->lock, flags);
 435
 436         frame_fmt &= ~FMT_DATA_BITS_MASK;
 437         switch (cflag & CSIZE) {
 438         case CS5:
 439                 frame_fmt |= FMT_DATA_BITS_5;
 440                 break;
 441         case CS6:
 442                 frame_fmt |= FMT_DATA_BITS_6;
 443                 break;
 444         case CS7:
 445                 frame_fmt |= FMT_DATA_BITS_7;
 446                 break;
 447         default:
 448         case CS8:
 449                 frame_fmt |= FMT_DATA_BITS_8;
 450                 break;
 451         }
 452
 453         /* manufacturer claims that this device can work with baud rates
 454          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 455          * guarantee that any other baud rate will work (especially
 456          * the higher ones)
 457          */
 458         br = tty_get_baud_rate(tty);
 459         if (br == 0) {
 460                 divisor = 0;
 461         } else {
 462                 int real_br;
 463                 int new_divisor;
 464                 br = min(br, OTI6858_MAX_BAUD_RATE);
 465
 466                 new_divisor = (96000000 + 8 * br) / (16 * br);
 467                 real_br = 96000000 / (16 * new_divisor);
 468                 divisor = cpu_to_le16(new_divisor);
 469                 tty_encode_baud_rate(tty, real_br, real_br);
 470         }
 471
 472         frame_fmt &= ~FMT_STOP_BITS_MASK;
 473         if ((cflag & CSTOPB) != 0)
 474                 frame_fmt |= FMT_STOP_BITS_2;
 475         else
 476                 frame_fmt |= FMT_STOP_BITS_1;
 477
 478         frame_fmt &= ~FMT_PARITY_MASK;
 479         if ((cflag & PARENB) != 0) {
 480                 if ((cflag & PARODD) != 0)
 481                         frame_fmt |= FMT_PARITY_ODD;
 482                 else
 483                         frame_fmt |= FMT_PARITY_EVEN;
 484         } else {
 485                 frame_fmt |= FMT_PARITY_NONE;
 486         }
 487
 488         control &= ~CONTROL_MASK;
 489         if ((cflag & CRTSCTS) != 0)
 490                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 491
 492         /* change control lines if we are switching to or from B0 */
 493         /* FIXME:
 494         spin_lock_irqsave(&priv->lock, flags);
 495         control = priv->line_control;
 496         if ((cflag & CBAUD) == B0)
 497                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 498         else
 499                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 500         if (control != priv->line_control) {
 501                 control = priv->line_control;
 502                 spin_unlock_irqrestore(&priv->lock, flags);
 503                 set_control_lines(serial->dev, control);
 504         } else {
 505                 spin_unlock_irqrestore(&priv->lock, flags);
 506         }
 507         */
 508
 509         spin_lock_irqsave(&priv->lock, flags);
 510         if (divisor != priv->pending_setup.divisor
 511                         || control != priv->pending_setup.control
 512                         || frame_fmt != priv->pending_setup.frame_fmt) {
 513                 priv->pending_setup.divisor = divisor;
 514                 priv->pending_setup.control = control;
 515                 priv->pending_setup.frame_fmt = frame_fmt;
 516         }
 517         spin_unlock_irqrestore(&priv->lock, flags);
 518 }
 519
 520 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
 521 {
 522         struct oti6858_private *priv = usb_get_serial_port_data(port);
 523         struct usb_serial *serial = port->serial;
 524         struct oti6858_control_pkt *buf;
 525         unsigned long flags;
 526         int result;
 527
 528         usb_clear_halt(serial->dev, port->write_urb->pipe);
 529         usb_clear_halt(serial->dev, port->read_urb->pipe);
 530
 531         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 532         if (!buf)
 533                 return -ENOMEM;
 534
 535         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 536                                 OTI6858_REQ_T_GET_STATUS,
 537                                 OTI6858_REQ_GET_STATUS,
 538                                 0, 0,
 539                                 buf, OTI6858_CTRL_PKT_SIZE,
 540                                 100);
 541         if (result != OTI6858_CTRL_PKT_SIZE) {
 542                 /* assume default (after power-on reset) values */
 543                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 544                 buf->frame_fmt = 0x03;  /* 8N1 */
 545                 buf->something = 0x43;
 546                 buf->control = 0x4c;    /* DTR, RTS */
 547                 buf->tx_status = 0x00;
 548                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 549                 buf->rx_bytes_avail = 0x00;
 550         }
 551
 552         spin_lock_irqsave(&priv->lock, flags);
 553         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 554         priv->pending_setup.divisor = buf->divisor;
 555         priv->pending_setup.frame_fmt = buf->frame_fmt;
 556         priv->pending_setup.control = buf->control;
 557         spin_unlock_irqrestore(&priv->lock, flags);
 558         kfree(buf);
 559
 560         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 561         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 562         if (result != 0) {
 563                 dev_err(&port->dev, "%s(): usb_submit_urb() failed with error %d\n",
 564                         __func__, result);
 565                 oti6858_close(port);
 566                 return result;
 567         }
 568
 569         /* setup termios */
 570         if (tty)
 571                 oti6858_set_termios(tty, port, NULL);
 572
 573         return 0;
 574 }
 575
 576 static void oti6858_close(struct usb_serial_port *port)
 577 {
 578         struct oti6858_private *priv = usb_get_serial_port_data(port);
 579         unsigned long flags;
 580
 581         spin_lock_irqsave(&port->lock, flags);
 582         /* clear out any remaining data in the buffer */
 583         kfifo_reset_out(&port->write_fifo);
 584         spin_unlock_irqrestore(&port->lock, flags);
 585
 586         dev_dbg(&port->dev, "%s(): after buf_clear()\n", __func__);
 587
 588         /* cancel scheduled setup */
 589         cancel_delayed_work_sync(&priv->delayed_setup_work);
 590         cancel_delayed_work_sync(&priv->delayed_write_work);
 591
 592         /* shutdown our urbs */
 593         dev_dbg(&port->dev, "%s(): shutting down urbs\n", __func__);
 594         usb_kill_urb(port->write_urb);
 595         usb_kill_urb(port->read_urb);
 596         usb_kill_urb(port->interrupt_in_urb);
 597 }
 598
 599 static int oti6858_tiocmset(struct tty_struct *tty,
 600                                 unsigned int set, unsigned int clear)
 601 {
 602         struct usb_serial_port *port = tty->driver_data;
 603         struct oti6858_private *priv = usb_get_serial_port_data(port);
 604         unsigned long flags;
 605         u8 control;
 606
 607         dev_dbg(&port->dev, "%s(set = 0x%08x, clear = 0x%08x)\n",
 608                 __func__, set, clear);
 609
 610         /* FIXME: check if this is correct (active high/low) */
 611         spin_lock_irqsave(&priv->lock, flags);
 612         control = priv->pending_setup.control;
 613         if ((set & TIOCM_RTS) != 0)
 614                 control |= CONTROL_RTS_HIGH;
 615         if ((set & TIOCM_DTR) != 0)
 616                 control |= CONTROL_DTR_HIGH;
 617         if ((clear & TIOCM_RTS) != 0)
 618                 control &= ~CONTROL_RTS_HIGH;
 619         if ((clear & TIOCM_DTR) != 0)
 620                 control &= ~CONTROL_DTR_HIGH;
 621
 622         if (control != priv->pending_setup.control)
 623                 priv->pending_setup.control = control;
 624
 625         spin_unlock_irqrestore(&priv->lock, flags);
 626         return 0;
 627 }
 628
 629 static int oti6858_tiocmget(struct tty_struct *tty)
 630 {
 631         struct usb_serial_port *port = tty->driver_data;
 632         struct oti6858_private *priv = usb_get_serial_port_data(port);
 633         unsigned long flags;
 634         unsigned pin_state;
 635         unsigned result = 0;
 636
 637         spin_lock_irqsave(&priv->lock, flags);
 638         pin_state = priv->status.pin_state & PIN_MASK;
 639         spin_unlock_irqrestore(&priv->lock, flags);
 640
 641         /* FIXME: check if this is correct (active high/low) */
 642         if ((pin_state & PIN_RTS) != 0)
 643                 result |= TIOCM_RTS;
 644         if ((pin_state & PIN_CTS) != 0)
 645                 result |= TIOCM_CTS;
 646         if ((pin_state & PIN_DSR) != 0)
 647                 result |= TIOCM_DSR;
 648         if ((pin_state & PIN_DTR) != 0)
 649                 result |= TIOCM_DTR;
 650         if ((pin_state & PIN_RI) != 0)
 651                 result |= TIOCM_RI;
 652         if ((pin_state & PIN_DCD) != 0)
 653                 result |= TIOCM_CD;
 654
 655         dev_dbg(&port->dev, "%s() = 0x%08x\n", __func__, result);
 656
 657         return result;
 658 }
 659
 660 static void oti6858_read_int_callback(struct urb *urb)
 661 {
 662         struct usb_serial_port *port =  urb->context;
 663         struct oti6858_private *priv = usb_get_serial_port_data(port);
 664         int transient = 0, can_recv = 0, resubmit = 1;
 665         int status = urb->status;
 666
 667         switch (status) {
 668         case 0:
 669                 /* success */
 670                 break;
 671         case -ECONNRESET:
 672         case -ENOENT:
 673         case -ESHUTDOWN:
 674                 /* this urb is terminated, clean up */
 675                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n",
 676                         __func__, status);
 677                 return;
 678         default:
 679                 dev_dbg(&urb->dev->dev, "%s(): nonzero urb status received: %d\n",
 680                         __func__, status);
 681                 break;
 682         }
 683
 684         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 685                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 686                 unsigned long flags;
 687
 688                 spin_lock_irqsave(&priv->lock, flags);
 689
 690                 if (!priv->transient) {
 691                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 692                                 if (xs->rx_bytes_avail == 0) {
 693                                         priv->transient = 4;
 694                                         priv->setup_done = 0;
 695                                         resubmit = 0;
 696                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 697                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 698                                 }
 699                         }
 700                 } else {
 701                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 702                                 priv->transient = 0;
 703                         } else if (!priv->setup_done) {
 704                                 resubmit = 0;
 705                         } else if (--priv->transient == 0) {
 706                                 if (xs->rx_bytes_avail == 0) {
 707                                         priv->transient = 4;
 708                                         priv->setup_done = 0;
 709                                         resubmit = 0;
 710                                         dev_dbg(&port->dev, "%s(): scheduling setup_line()\n", __func__);
 711                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 712                                 }
 713                         }
 714                 }
 715
 716                 if (!priv->transient) {
 717                         u8 delta = xs->pin_state ^ priv->status.pin_state;
 718
 719                         if (delta & PIN_MSR_MASK) {
 720                                 if (delta & PIN_CTS)
 721                                         port->icount.cts++;
 722                                 if (delta & PIN_DSR)
 723                                         port->icount.dsr++;
 724                                 if (delta & PIN_RI)
 725                                         port->icount.rng++;
 726                                 if (delta & PIN_DCD)
 727                                         port->icount.dcd++;
 728
 729                                 wake_up_interruptible(&port->port.delta_msr_wait);
 730                         }
 731
 732                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 733                 }
 734
 735                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 736                         can_recv = xs->rx_bytes_avail;
 737                         priv->flags.read_urb_in_use = 1;
 738                 }
 739
 740                 transient = priv->transient;
 741                 spin_unlock_irqrestore(&priv->lock, flags);
 742         }
 743
 744         if (can_recv) {
 745                 int result;
 746
 747                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 748                 if (result != 0) {
 749                         priv->flags.read_urb_in_use = 0;
 750                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 751                                         " error %d\n", __func__, result);
 752                 } else {
 753                         resubmit = 0;
 754                 }
 755         } else if (!transient) {
 756                 unsigned long flags;
 757                 int count;
 758
 759                 spin_lock_irqsave(&port->lock, flags);
 760                 count = kfifo_len(&port->write_fifo);
 761                 spin_unlock_irqrestore(&port->lock, flags);
 762
 763                 spin_lock_irqsave(&priv->lock, flags);
 764                 if (priv->flags.write_urb_in_use == 0 && count != 0) {
 765                         schedule_delayed_work(&priv->delayed_write_work, 0);
 766                         resubmit = 0;
 767                 }
 768                 spin_unlock_irqrestore(&priv->lock, flags);
 769         }
 770
 771         if (resubmit) {
 772                 int result;
 773
 774 /*              dev_dbg(&urb->dev->dev, "%s(): submitting interrupt urb\n", __func__); */
 775                 result = usb_submit_urb(urb, GFP_ATOMIC);
 776                 if (result != 0) {
 777                         dev_err(&urb->dev->dev,
 778                                         "%s(): usb_submit_urb() failed with"
 779                                         " error %d\n", __func__, result);
 780                 }
 781         }
 782 }
 783
 784 static void oti6858_read_bulk_callback(struct urb *urb)
 785 {
 786         struct usb_serial_port *port =  urb->context;
 787         struct oti6858_private *priv = usb_get_serial_port_data(port);
 788         unsigned char *data = urb->transfer_buffer;
 789         unsigned long flags;
 790         int status = urb->status;
 791         int result;
 792
 793         spin_lock_irqsave(&priv->lock, flags);
 794         priv->flags.read_urb_in_use = 0;
 795         spin_unlock_irqrestore(&priv->lock, flags);
 796
 797         if (status != 0) {
 798                 dev_dbg(&urb->dev->dev, "%s(): unable to handle the error, exiting\n", __func__);
 799                 return;
 800         }
 801
 802         if (urb->actual_length > 0) {
 803                 tty_insert_flip_string(&port->port, data, urb->actual_length);
 804                 tty_flip_buffer_push(&port->port);
 805         }
 806
 807         /* schedule the interrupt urb */
 808         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 809         if (result != 0 && result != -EPERM) {
 810                 dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 811                                 " error %d\n", __func__, result);
 812         }
 813 }
 814
 815 static void oti6858_write_bulk_callback(struct urb *urb)
 816 {
 817         struct usb_serial_port *port =  urb->context;
 818         struct oti6858_private *priv = usb_get_serial_port_data(port);
 819         int status = urb->status;
 820         int result;
 821
 822         switch (status) {
 823         case 0:
 824                 /* success */
 825                 break;
 826         case -ECONNRESET:
 827         case -ENOENT:
 828         case -ESHUTDOWN:
 829                 /* this urb is terminated, clean up */
 830                 dev_dbg(&urb->dev->dev, "%s(): urb shutting down with status: %d\n", __func__, status);
 831                 priv->flags.write_urb_in_use = 0;
 832                 return;
 833         default:
 834                 /* error in the urb, so we have to resubmit it */
 835                 dev_dbg(&urb->dev->dev, "%s(): nonzero write bulk status received: %d\n", __func__, status);
 836                 dev_dbg(&urb->dev->dev, "%s(): overflow in write\n", __func__);
 837
 838                 port->write_urb->transfer_buffer_length = 1;
 839                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 840                 if (result) {
 841                         dev_err_console(port, "%s(): usb_submit_urb() failed,"
 842                                         " error %d\n", __func__, result);
 843                 } else {
 844                         return;
 845                 }
 846         }
 847
 848         priv->flags.write_urb_in_use = 0;
 849
 850         /* schedule the interrupt urb if we are still open */
 851         dev_dbg(&port->dev, "%s(): submitting interrupt urb\n", __func__);
 852         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 853         if (result != 0) {
 854                 dev_err(&port->dev, "%s(): failed submitting int urb,"
 855                                         " error %d\n", __func__, result);
 856         }
 857 }
 858
 859 module_usb_serial_driver(serial_drivers, id_table);
 860
 861 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
 862 MODULE_AUTHOR(OTI6858_AUTHOR);
 863 MODULE_LICENSE("GPL");