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 "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 #define OTI6858_VERSION "0.1"
  60
  61 static 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 static struct usb_driver oti6858_driver = {
  69         .name =         "oti6858",
  70         .probe =        usb_serial_probe,
  71         .disconnect =   usb_serial_disconnect,
  72         .id_table =     id_table,
  73         .no_dynamic_id =        1,
  74 };
  75
  76 static int debug;
  77
  78
  79 /* buffering code, copied from pl2303 driver */
  80 #define PL2303_BUF_SIZE         1024
  81 #define PL2303_TMP_BUF_SIZE     1024
  82
  83 struct oti6858_buf {
  84         unsigned int    buf_size;
  85         char            *buf_buf;
  86         char            *buf_get;
  87         char            *buf_put;
  88 };
  89
  90 /* requests */
  91 #define OTI6858_REQ_GET_STATUS          (USB_DIR_IN | USB_TYPE_VENDOR | 0x00)
  92 #define OTI6858_REQ_T_GET_STATUS        0x01
  93
  94 #define OTI6858_REQ_SET_LINE            (USB_DIR_OUT | USB_TYPE_VENDOR | 0x00)
  95 #define OTI6858_REQ_T_SET_LINE          0x00
  96
  97 #define OTI6858_REQ_CHECK_TXBUFF        (USB_DIR_IN | USB_TYPE_VENDOR | 0x01)
  98 #define OTI6858_REQ_T_CHECK_TXBUFF      0x00
  99
 100 /* format of the control packet */
 101 struct oti6858_control_pkt {
 102         __le16  divisor;        /* baud rate = 96000000 / (16 * divisor), LE */
 103 #define OTI6858_MAX_BAUD_RATE   3000000
 104         u8      frame_fmt;
 105 #define FMT_STOP_BITS_MASK      0xc0
 106 #define FMT_STOP_BITS_1         0x00
 107 #define FMT_STOP_BITS_2         0x40    /* 1.5 stop bits if FMT_DATA_BITS_5 */
 108 #define FMT_PARITY_MASK         0x38
 109 #define FMT_PARITY_NONE         0x00
 110 #define FMT_PARITY_ODD          0x08
 111 #define FMT_PARITY_EVEN         0x18
 112 #define FMT_PARITY_MARK         0x28
 113 #define FMT_PARITY_SPACE        0x38
 114 #define FMT_DATA_BITS_MASK      0x03
 115 #define FMT_DATA_BITS_5         0x00
 116 #define FMT_DATA_BITS_6         0x01
 117 #define FMT_DATA_BITS_7         0x02
 118 #define FMT_DATA_BITS_8         0x03
 119         u8      something;      /* always equals 0x43 */
 120         u8      control;        /* settings of flow control lines */
 121 #define CONTROL_MASK            0x0c
 122 #define CONTROL_DTR_HIGH        0x08
 123 #define CONTROL_RTS_HIGH        0x04
 124         u8      tx_status;
 125 #define TX_BUFFER_EMPTIED       0x09
 126         u8      pin_state;
 127 #define PIN_MASK                0x3f
 128 #define PIN_RTS                 0x20    /* output pin */
 129 #define PIN_CTS                 0x10    /* input pin, active low */
 130 #define PIN_DSR                 0x08    /* input pin, active low */
 131 #define PIN_DTR                 0x04    /* output pin */
 132 #define PIN_RI                  0x02    /* input pin, active low */
 133 #define PIN_DCD                 0x01    /* input pin, active low */
 134         u8      rx_bytes_avail;         /* number of bytes in rx buffer */;
 135 };
 136
 137 #define OTI6858_CTRL_PKT_SIZE   sizeof(struct oti6858_control_pkt)
 138 #define OTI6858_CTRL_EQUALS_PENDING(a, priv) \
 139         (((a)->divisor == (priv)->pending_setup.divisor) \
 140           && ((a)->control == (priv)->pending_setup.control) \
 141           && ((a)->frame_fmt == (priv)->pending_setup.frame_fmt))
 142
 143 /* function prototypes */
 144 static int oti6858_open(struct tty_struct *tty,
 145                         struct usb_serial_port *port, struct file *filp);
 146 static void oti6858_close(struct usb_serial_port *port);
 147 static void oti6858_set_termios(struct tty_struct *tty,
 148                         struct usb_serial_port *port, struct ktermios *old);
 149 static int oti6858_ioctl(struct tty_struct *tty, struct file *file,
 150                         unsigned int cmd, unsigned long arg);
 151 static void oti6858_read_int_callback(struct urb *urb);
 152 static void oti6858_read_bulk_callback(struct urb *urb);
 153 static void oti6858_write_bulk_callback(struct urb *urb);
 154 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 155                         const unsigned char *buf, int count);
 156 static int oti6858_write_room(struct tty_struct *tty);
 157 static int oti6858_chars_in_buffer(struct tty_struct *tty);
 158 static int oti6858_tiocmget(struct tty_struct *tty, struct file *file);
 159 static int oti6858_tiocmset(struct tty_struct *tty, struct file *file,
 160                                 unsigned int set, unsigned int clear);
 161 static int oti6858_startup(struct usb_serial *serial);
 162 static void oti6858_release(struct usb_serial *serial);
 163
 164 /* functions operating on buffers */
 165 static struct oti6858_buf *oti6858_buf_alloc(unsigned int size);
 166 static void oti6858_buf_free(struct oti6858_buf *pb);
 167 static void oti6858_buf_clear(struct oti6858_buf *pb);
 168 static unsigned int oti6858_buf_data_avail(struct oti6858_buf *pb);
 169 static unsigned int oti6858_buf_space_avail(struct oti6858_buf *pb);
 170 static unsigned int oti6858_buf_put(struct oti6858_buf *pb, const char *buf,
 171                                         unsigned int count);
 172 static unsigned int oti6858_buf_get(struct oti6858_buf *pb, char *buf,
 173                                         unsigned int count);
 174
 175
 176 /* device info */
 177 static struct usb_serial_driver oti6858_device = {
 178         .driver = {
 179                 .owner =        THIS_MODULE,
 180                 .name =         "oti6858",
 181         },
 182         .id_table =             id_table,
 183         .num_ports =            1,
 184         .open =                 oti6858_open,
 185         .close =                oti6858_close,
 186         .write =                oti6858_write,
 187         .ioctl =                oti6858_ioctl,
 188         .set_termios =          oti6858_set_termios,
 189         .tiocmget =             oti6858_tiocmget,
 190         .tiocmset =             oti6858_tiocmset,
 191         .read_bulk_callback =   oti6858_read_bulk_callback,
 192         .read_int_callback =    oti6858_read_int_callback,
 193         .write_bulk_callback =  oti6858_write_bulk_callback,
 194         .write_room =           oti6858_write_room,
 195         .chars_in_buffer =      oti6858_chars_in_buffer,
 196         .attach =               oti6858_startup,
 197         .release =              oti6858_release,
 198 };
 199
 200 struct oti6858_private {
 201         spinlock_t lock;
 202
 203         struct oti6858_buf *buf;
 204         struct oti6858_control_pkt status;
 205
 206         struct {
 207                 u8 read_urb_in_use;
 208                 u8 write_urb_in_use;
 209                 u8 termios_initialized;
 210         } flags;
 211         struct delayed_work delayed_write_work;
 212
 213         struct {
 214                 __le16 divisor;
 215                 u8 frame_fmt;
 216                 u8 control;
 217         } pending_setup;
 218         u8 transient;
 219         u8 setup_done;
 220         struct delayed_work delayed_setup_work;
 221
 222         wait_queue_head_t intr_wait;
 223         struct usb_serial_port *port;   /* USB port with which associated */
 224 };
 225
 226 static void setup_line(struct work_struct *work)
 227 {
 228         struct oti6858_private *priv = container_of(work,
 229                         struct oti6858_private, delayed_setup_work.work);
 230         struct usb_serial_port *port = priv->port;
 231         struct oti6858_control_pkt *new_setup;
 232         unsigned long flags;
 233         int result;
 234
 235         dbg("%s(port = %d)", __func__, port->number);
 236
 237         new_setup = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 238         if (new_setup == NULL) {
 239                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 240                 /* we will try again */
 241                 schedule_delayed_work(&priv->delayed_setup_work,
 242                                                 msecs_to_jiffies(2));
 243                 return;
 244         }
 245
 246         result = usb_control_msg(port->serial->dev,
 247                                 usb_rcvctrlpipe(port->serial->dev, 0),
 248                                 OTI6858_REQ_T_GET_STATUS,
 249                                 OTI6858_REQ_GET_STATUS,
 250                                 0, 0,
 251                                 new_setup, OTI6858_CTRL_PKT_SIZE,
 252                                 100);
 253
 254         if (result != OTI6858_CTRL_PKT_SIZE) {
 255                 dev_err(&port->dev, "%s(): error reading status\n", __func__);
 256                 kfree(new_setup);
 257                 /* we will try again */
 258                 schedule_delayed_work(&priv->delayed_setup_work,
 259                                                         msecs_to_jiffies(2));
 260                 return;
 261         }
 262
 263         spin_lock_irqsave(&priv->lock, flags);
 264         if (!OTI6858_CTRL_EQUALS_PENDING(new_setup, priv)) {
 265                 new_setup->divisor = priv->pending_setup.divisor;
 266                 new_setup->control = priv->pending_setup.control;
 267                 new_setup->frame_fmt = priv->pending_setup.frame_fmt;
 268
 269                 spin_unlock_irqrestore(&priv->lock, flags);
 270                 result = usb_control_msg(port->serial->dev,
 271                                         usb_sndctrlpipe(port->serial->dev, 0),
 272                                         OTI6858_REQ_T_SET_LINE,
 273                                         OTI6858_REQ_SET_LINE,
 274                                         0, 0,
 275                                         new_setup, OTI6858_CTRL_PKT_SIZE,
 276                                         100);
 277         } else {
 278                 spin_unlock_irqrestore(&priv->lock, flags);
 279                 result = 0;
 280         }
 281         kfree(new_setup);
 282
 283         spin_lock_irqsave(&priv->lock, flags);
 284         if (result != OTI6858_CTRL_PKT_SIZE)
 285                 priv->transient = 0;
 286         priv->setup_done = 1;
 287         spin_unlock_irqrestore(&priv->lock, flags);
 288
 289         dbg("%s(): submitting interrupt urb", __func__);
 290         port->interrupt_in_urb->dev = port->serial->dev;
 291         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 292         if (result != 0) {
 293                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 294                                 " with error %d\n", __func__, result);
 295         }
 296 }
 297
 298 void send_data(struct work_struct *work)
 299 {
 300         struct oti6858_private *priv = container_of(work,
 301                         struct oti6858_private, delayed_write_work.work);
 302         struct usb_serial_port *port = priv->port;
 303         int count = 0, result;
 304         unsigned long flags;
 305         unsigned char allow;
 306
 307         dbg("%s(port = %d)", __func__, port->number);
 308
 309         spin_lock_irqsave(&priv->lock, flags);
 310         if (priv->flags.write_urb_in_use) {
 311                 spin_unlock_irqrestore(&priv->lock, flags);
 312                 schedule_delayed_work(&priv->delayed_write_work,
 313                                                 msecs_to_jiffies(2));
 314                 return;
 315         }
 316         priv->flags.write_urb_in_use = 1;
 317
 318         count = oti6858_buf_data_avail(priv->buf);
 319         spin_unlock_irqrestore(&priv->lock, flags);
 320         if (count > port->bulk_out_size)
 321                 count = port->bulk_out_size;
 322
 323         if (count != 0) {
 324                 result = usb_control_msg(port->serial->dev,
 325                                 usb_rcvctrlpipe(port->serial->dev, 0),
 326                                 OTI6858_REQ_T_CHECK_TXBUFF,
 327                                 OTI6858_REQ_CHECK_TXBUFF,
 328                                 count, 0, &allow, 1, 100);
 329                 if (result != 1 || allow != 0)
 330                         count = 0;
 331         }
 332
 333         if (count == 0) {
 334                 priv->flags.write_urb_in_use = 0;
 335
 336                 dbg("%s(): submitting interrupt urb", __func__);
 337                 port->interrupt_in_urb->dev = port->serial->dev;
 338                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 339                 if (result != 0) {
 340                         dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 341                                 " with error %d\n", __func__, result);
 342                 }
 343                 return;
 344         }
 345
 346         spin_lock_irqsave(&priv->lock, flags);
 347         oti6858_buf_get(priv->buf, port->write_urb->transfer_buffer, count);
 348         spin_unlock_irqrestore(&priv->lock, flags);
 349
 350         port->write_urb->transfer_buffer_length = count;
 351         port->write_urb->dev = port->serial->dev;
 352         result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 353         if (result != 0) {
 354                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 355                                " with error %d\n", __func__, result);
 356                 priv->flags.write_urb_in_use = 0;
 357         }
 358
 359         usb_serial_port_softint(port);
 360 }
 361
 362 static int oti6858_startup(struct usb_serial *serial)
 363 {
 364         struct usb_serial_port *port = serial->port[0];
 365         struct oti6858_private *priv;
 366         int i;
 367
 368         for (i = 0; i < serial->num_ports; ++i) {
 369                 priv = kzalloc(sizeof(struct oti6858_private), GFP_KERNEL);
 370                 if (!priv)
 371                         break;
 372                 priv->buf = oti6858_buf_alloc(PL2303_BUF_SIZE);
 373                 if (priv->buf == NULL) {
 374                         kfree(priv);
 375                         break;
 376                 }
 377
 378                 spin_lock_init(&priv->lock);
 379                 init_waitqueue_head(&priv->intr_wait);
 380 /*              INIT_WORK(&priv->setup_work, setup_line, serial->port[i]); */
 381 /*              INIT_WORK(&priv->write_work, send_data, serial->port[i]); */
 382                 priv->port = port;
 383                 INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 384                 INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 385
 386                 usb_set_serial_port_data(serial->port[i], priv);
 387         }
 388         if (i == serial->num_ports)
 389                 return 0;
 390
 391         for (--i; i >= 0; --i) {
 392                 priv = usb_get_serial_port_data(serial->port[i]);
 393                 oti6858_buf_free(priv->buf);
 394                 kfree(priv);
 395                 usb_set_serial_port_data(serial->port[i], NULL);
 396         }
 397         return -ENOMEM;
 398 }
 399
 400 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 401                         const unsigned char *buf, int count)
 402 {
 403         struct oti6858_private *priv = usb_get_serial_port_data(port);
 404         unsigned long flags;
 405
 406         dbg("%s(port = %d, count = %d)", __func__, port->number, count);
 407
 408         if (!count)
 409                 return count;
 410
 411         spin_lock_irqsave(&priv->lock, flags);
 412         count = oti6858_buf_put(priv->buf, buf, count);
 413         spin_unlock_irqrestore(&priv->lock, flags);
 414
 415         return count;
 416 }
 417
 418 static int oti6858_write_room(struct tty_struct *tty)
 419 {
 420         struct usb_serial_port *port = tty->driver_data;
 421         struct oti6858_private *priv = usb_get_serial_port_data(port);
 422         int room = 0;
 423         unsigned long flags;
 424
 425         dbg("%s(port = %d)", __func__, port->number);
 426
 427         spin_lock_irqsave(&priv->lock, flags);
 428         room = oti6858_buf_space_avail(priv->buf);
 429         spin_unlock_irqrestore(&priv->lock, flags);
 430
 431         return room;
 432 }
 433
 434 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 435 {
 436         struct usb_serial_port *port = tty->driver_data;
 437         struct oti6858_private *priv = usb_get_serial_port_data(port);
 438         int chars = 0;
 439         unsigned long flags;
 440
 441         dbg("%s(port = %d)", __func__, port->number);
 442
 443         spin_lock_irqsave(&priv->lock, flags);
 444         chars = oti6858_buf_data_avail(priv->buf);
 445         spin_unlock_irqrestore(&priv->lock, flags);
 446
 447         return chars;
 448 }
 449
 450 static void oti6858_set_termios(struct tty_struct *tty,
 451                 struct usb_serial_port *port, struct ktermios *old_termios)
 452 {
 453         struct oti6858_private *priv = usb_get_serial_port_data(port);
 454         unsigned long flags;
 455         unsigned int cflag;
 456         u8 frame_fmt, control;
 457         __le16 divisor;
 458         int br;
 459
 460         dbg("%s(port = %d)", __func__, port->number);
 461
 462         if (!tty) {
 463                 dbg("%s(): no tty structures", __func__);
 464                 return;
 465         }
 466
 467         spin_lock_irqsave(&priv->lock, flags);
 468         if (!priv->flags.termios_initialized) {
 469                 *(tty->termios) = tty_std_termios;
 470                 tty->termios->c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
 471                 tty->termios->c_ispeed = 38400;
 472                 tty->termios->c_ospeed = 38400;
 473                 priv->flags.termios_initialized = 1;
 474         }
 475         spin_unlock_irqrestore(&priv->lock, flags);
 476
 477         cflag = tty->termios->c_cflag;
 478
 479         spin_lock_irqsave(&priv->lock, flags);
 480         divisor = priv->pending_setup.divisor;
 481         frame_fmt = priv->pending_setup.frame_fmt;
 482         control = priv->pending_setup.control;
 483         spin_unlock_irqrestore(&priv->lock, flags);
 484
 485         frame_fmt &= ~FMT_DATA_BITS_MASK;
 486         switch (cflag & CSIZE) {
 487         case CS5:
 488                 frame_fmt |= FMT_DATA_BITS_5;
 489                 break;
 490         case CS6:
 491                 frame_fmt |= FMT_DATA_BITS_6;
 492                 break;
 493         case CS7:
 494                 frame_fmt |= FMT_DATA_BITS_7;
 495                 break;
 496         default:
 497         case CS8:
 498                 frame_fmt |= FMT_DATA_BITS_8;
 499                 break;
 500         }
 501
 502         /* manufacturer claims that this device can work with baud rates
 503          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 504          * guarantee that any other baud rate will work (especially
 505          * the higher ones)
 506          */
 507         br = tty_get_baud_rate(tty);
 508         if (br == 0) {
 509                 divisor = 0;
 510         } else {
 511                 int real_br;
 512                 int new_divisor;
 513                 br = min(br, OTI6858_MAX_BAUD_RATE);
 514
 515                 new_divisor = (96000000 + 8 * br) / (16 * br);
 516                 real_br = 96000000 / (16 * new_divisor);
 517                 divisor = cpu_to_le16(new_divisor);
 518                 tty_encode_baud_rate(tty, real_br, real_br);
 519         }
 520
 521         frame_fmt &= ~FMT_STOP_BITS_MASK;
 522         if ((cflag & CSTOPB) != 0)
 523                 frame_fmt |= FMT_STOP_BITS_2;
 524         else
 525                 frame_fmt |= FMT_STOP_BITS_1;
 526
 527         frame_fmt &= ~FMT_PARITY_MASK;
 528         if ((cflag & PARENB) != 0) {
 529                 if ((cflag & PARODD) != 0)
 530                         frame_fmt |= FMT_PARITY_ODD;
 531                 else
 532                         frame_fmt |= FMT_PARITY_EVEN;
 533         } else {
 534                 frame_fmt |= FMT_PARITY_NONE;
 535         }
 536
 537         control &= ~CONTROL_MASK;
 538         if ((cflag & CRTSCTS) != 0)
 539                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 540
 541         /* change control lines if we are switching to or from B0 */
 542         /* FIXME:
 543         spin_lock_irqsave(&priv->lock, flags);
 544         control = priv->line_control;
 545         if ((cflag & CBAUD) == B0)
 546                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 547         else
 548                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 549         if (control != priv->line_control) {
 550                 control = priv->line_control;
 551                 spin_unlock_irqrestore(&priv->lock, flags);
 552                 set_control_lines(serial->dev, control);
 553         } else {
 554                 spin_unlock_irqrestore(&priv->lock, flags);
 555         }
 556         */
 557
 558         spin_lock_irqsave(&priv->lock, flags);
 559         if (divisor != priv->pending_setup.divisor
 560                         || control != priv->pending_setup.control
 561                         || frame_fmt != priv->pending_setup.frame_fmt) {
 562                 priv->pending_setup.divisor = divisor;
 563                 priv->pending_setup.control = control;
 564                 priv->pending_setup.frame_fmt = frame_fmt;
 565         }
 566         spin_unlock_irqrestore(&priv->lock, flags);
 567 }
 568
 569 static int oti6858_open(struct tty_struct *tty,
 570                         struct usb_serial_port *port, struct file *filp)
 571 {
 572         struct oti6858_private *priv = usb_get_serial_port_data(port);
 573         struct ktermios tmp_termios;
 574         struct usb_serial *serial = port->serial;
 575         struct oti6858_control_pkt *buf;
 576         unsigned long flags;
 577         int result;
 578
 579         dbg("%s(port = %d)", __func__, port->number);
 580
 581         usb_clear_halt(serial->dev, port->write_urb->pipe);
 582         usb_clear_halt(serial->dev, port->read_urb->pipe);
 583
 584         if (port->port.count != 1)
 585                 return 0;
 586
 587         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 588         if (buf == NULL) {
 589                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 590                 return -ENOMEM;
 591         }
 592
 593         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 594                                 OTI6858_REQ_T_GET_STATUS,
 595                                 OTI6858_REQ_GET_STATUS,
 596                                 0, 0,
 597                                 buf, OTI6858_CTRL_PKT_SIZE,
 598                                 100);
 599         if (result != OTI6858_CTRL_PKT_SIZE) {
 600                 /* assume default (after power-on reset) values */
 601                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 602                 buf->frame_fmt = 0x03;  /* 8N1 */
 603                 buf->something = 0x43;
 604                 buf->control = 0x4c;    /* DTR, RTS */
 605                 buf->tx_status = 0x00;
 606                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 607                 buf->rx_bytes_avail = 0x00;
 608         }
 609
 610         spin_lock_irqsave(&priv->lock, flags);
 611         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 612         priv->pending_setup.divisor = buf->divisor;
 613         priv->pending_setup.frame_fmt = buf->frame_fmt;
 614         priv->pending_setup.control = buf->control;
 615         spin_unlock_irqrestore(&priv->lock, flags);
 616         kfree(buf);
 617
 618         dbg("%s(): submitting interrupt urb", __func__);
 619         port->interrupt_in_urb->dev = serial->dev;
 620         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 621         if (result != 0) {
 622                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 623                                " with error %d\n", __func__, result);
 624                 oti6858_close(port);
 625                 return -EPROTO;
 626         }
 627
 628         /* setup termios */
 629         if (tty)
 630                 oti6858_set_termios(tty, port, &tmp_termios);
 631         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 632         return 0;
 633 }
 634
 635 static void oti6858_close(struct usb_serial_port *port)
 636 {
 637         struct oti6858_private *priv = usb_get_serial_port_data(port);
 638         unsigned long flags;
 639
 640         dbg("%s(port = %d)", __func__, port->number);
 641
 642         spin_lock_irqsave(&priv->lock, flags);
 643         /* clear out any remaining data in the buffer */
 644         oti6858_buf_clear(priv->buf);
 645         spin_unlock_irqrestore(&priv->lock, flags);
 646
 647         dbg("%s(): after buf_clear()", __func__);
 648
 649         /* cancel scheduled setup */
 650         cancel_delayed_work(&priv->delayed_setup_work);
 651         cancel_delayed_work(&priv->delayed_write_work);
 652         flush_scheduled_work();
 653
 654         /* shutdown our urbs */
 655         dbg("%s(): shutting down urbs", __func__);
 656         usb_kill_urb(port->write_urb);
 657         usb_kill_urb(port->read_urb);
 658         usb_kill_urb(port->interrupt_in_urb);
 659 }
 660
 661 static int oti6858_tiocmset(struct tty_struct *tty, struct file *file,
 662                                 unsigned int set, unsigned int clear)
 663 {
 664         struct usb_serial_port *port = tty->driver_data;
 665         struct oti6858_private *priv = usb_get_serial_port_data(port);
 666         unsigned long flags;
 667         u8 control;
 668
 669         dbg("%s(port = %d, set = 0x%08x, clear = 0x%08x)",
 670                                 __func__, port->number, set, clear);
 671
 672         if (!usb_get_intfdata(port->serial->interface))
 673                 return -ENODEV;
 674
 675         /* FIXME: check if this is correct (active high/low) */
 676         spin_lock_irqsave(&priv->lock, flags);
 677         control = priv->pending_setup.control;
 678         if ((set & TIOCM_RTS) != 0)
 679                 control |= CONTROL_RTS_HIGH;
 680         if ((set & TIOCM_DTR) != 0)
 681                 control |= CONTROL_DTR_HIGH;
 682         if ((clear & TIOCM_RTS) != 0)
 683                 control &= ~CONTROL_RTS_HIGH;
 684         if ((clear & TIOCM_DTR) != 0)
 685                 control &= ~CONTROL_DTR_HIGH;
 686
 687         if (control != priv->pending_setup.control)
 688                 priv->pending_setup.control = control;
 689
 690         spin_unlock_irqrestore(&priv->lock, flags);
 691         return 0;
 692 }
 693
 694 static int oti6858_tiocmget(struct tty_struct *tty, struct file *file)
 695 {
 696         struct usb_serial_port *port = tty->driver_data;
 697         struct oti6858_private *priv = usb_get_serial_port_data(port);
 698         unsigned long flags;
 699         unsigned pin_state;
 700         unsigned result = 0;
 701
 702         dbg("%s(port = %d)", __func__, port->number);
 703
 704         if (!usb_get_intfdata(port->serial->interface))
 705                 return -ENODEV;
 706
 707         spin_lock_irqsave(&priv->lock, flags);
 708         pin_state = priv->status.pin_state & PIN_MASK;
 709         spin_unlock_irqrestore(&priv->lock, flags);
 710
 711         /* FIXME: check if this is correct (active high/low) */
 712         if ((pin_state & PIN_RTS) != 0)
 713                 result |= TIOCM_RTS;
 714         if ((pin_state & PIN_CTS) != 0)
 715                 result |= TIOCM_CTS;
 716         if ((pin_state & PIN_DSR) != 0)
 717                 result |= TIOCM_DSR;
 718         if ((pin_state & PIN_DTR) != 0)
 719                 result |= TIOCM_DTR;
 720         if ((pin_state & PIN_RI) != 0)
 721                 result |= TIOCM_RI;
 722         if ((pin_state & PIN_DCD) != 0)
 723                 result |= TIOCM_CD;
 724
 725         dbg("%s() = 0x%08x", __func__, result);
 726
 727         return result;
 728 }
 729
 730 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 731 {
 732         struct oti6858_private *priv = usb_get_serial_port_data(port);
 733         unsigned long flags;
 734         unsigned int prev, status;
 735         unsigned int changed;
 736
 737         spin_lock_irqsave(&priv->lock, flags);
 738         prev = priv->status.pin_state;
 739         spin_unlock_irqrestore(&priv->lock, flags);
 740
 741         while (1) {
 742                 wait_event_interruptible(priv->intr_wait,
 743                                         priv->status.pin_state != prev);
 744                 if (signal_pending(current))
 745                         return -ERESTARTSYS;
 746
 747                 spin_lock_irqsave(&priv->lock, flags);
 748                 status = priv->status.pin_state & PIN_MASK;
 749                 spin_unlock_irqrestore(&priv->lock, flags);
 750
 751                 changed = prev ^ status;
 752                 /* FIXME: check if this is correct (active high/low) */
 753                 if (((arg & TIOCM_RNG) && (changed & PIN_RI)) ||
 754                     ((arg & TIOCM_DSR) && (changed & PIN_DSR)) ||
 755                     ((arg & TIOCM_CD)  && (changed & PIN_DCD)) ||
 756                     ((arg & TIOCM_CTS) && (changed & PIN_CTS)))
 757                         return 0;
 758                 prev = status;
 759         }
 760
 761         /* NOTREACHED */
 762         return 0;
 763 }
 764
 765 static int oti6858_ioctl(struct tty_struct *tty, struct file *file,
 766                         unsigned int cmd, unsigned long arg)
 767 {
 768         struct usb_serial_port *port = tty->driver_data;
 769
 770         dbg("%s(port = %d, cmd = 0x%04x, arg = 0x%08lx)",
 771                                 __func__, port->number, cmd, arg);
 772
 773         switch (cmd) {
 774         case TIOCMIWAIT:
 775                 dbg("%s(): TIOCMIWAIT", __func__);
 776                 return wait_modem_info(port, arg);
 777         default:
 778                 dbg("%s(): 0x%04x not supported", __func__, cmd);
 779                 break;
 780         }
 781         return -ENOIOCTLCMD;
 782 }
 783
 784
 785 static void oti6858_release(struct usb_serial *serial)
 786 {
 787         struct oti6858_private *priv;
 788         int i;
 789
 790         dbg("%s()", __func__);
 791
 792         for (i = 0; i < serial->num_ports; ++i) {
 793                 priv = usb_get_serial_port_data(serial->port[i]);
 794                 if (priv) {
 795                         oti6858_buf_free(priv->buf);
 796                         kfree(priv);
 797                 }
 798         }
 799 }
 800
 801 static void oti6858_read_int_callback(struct urb *urb)
 802 {
 803         struct usb_serial_port *port =  urb->context;
 804         struct oti6858_private *priv = usb_get_serial_port_data(port);
 805         int transient = 0, can_recv = 0, resubmit = 1;
 806         int status = urb->status;
 807
 808         dbg("%s(port = %d, status = %d)",
 809                                 __func__, port->number, status);
 810
 811         switch (status) {
 812         case 0:
 813                 /* success */
 814                 break;
 815         case -ECONNRESET:
 816         case -ENOENT:
 817         case -ESHUTDOWN:
 818                 /* this urb is terminated, clean up */
 819                 dbg("%s(): urb shutting down with status: %d",
 820                                         __func__, status);
 821                 return;
 822         default:
 823                 dbg("%s(): nonzero urb status received: %d",
 824                                         __func__, status);
 825                 break;
 826         }
 827
 828         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 829                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 830                 unsigned long flags;
 831
 832                 spin_lock_irqsave(&priv->lock, flags);
 833
 834                 if (!priv->transient) {
 835                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 836                                 if (xs->rx_bytes_avail == 0) {
 837                                         priv->transient = 4;
 838                                         priv->setup_done = 0;
 839                                         resubmit = 0;
 840                                         dbg("%s(): scheduling setup_line()",
 841                                             __func__);
 842                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 843                                 }
 844                         }
 845                 } else {
 846                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 847                                 priv->transient = 0;
 848                         } else if (!priv->setup_done) {
 849                                 resubmit = 0;
 850                         } else if (--priv->transient == 0) {
 851                                 if (xs->rx_bytes_avail == 0) {
 852                                         priv->transient = 4;
 853                                         priv->setup_done = 0;
 854                                         resubmit = 0;
 855                                         dbg("%s(): scheduling setup_line()",
 856                                             __func__);
 857                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 858                                 }
 859                         }
 860                 }
 861
 862                 if (!priv->transient) {
 863                         if (xs->pin_state != priv->status.pin_state)
 864                                 wake_up_interruptible(&priv->intr_wait);
 865                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 866                 }
 867
 868                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 869                         can_recv = xs->rx_bytes_avail;
 870                         priv->flags.read_urb_in_use = 1;
 871                 }
 872
 873                 transient = priv->transient;
 874                 spin_unlock_irqrestore(&priv->lock, flags);
 875         }
 876
 877         if (can_recv) {
 878                 int result;
 879
 880                 port->read_urb->dev = port->serial->dev;
 881                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 882                 if (result != 0) {
 883                         priv->flags.read_urb_in_use = 0;
 884                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 885                                         " error %d\n", __func__, result);
 886                 } else {
 887                         resubmit = 0;
 888                 }
 889         } else if (!transient) {
 890                 unsigned long flags;
 891
 892                 spin_lock_irqsave(&priv->lock, flags);
 893                 if (priv->flags.write_urb_in_use == 0
 894                                 && oti6858_buf_data_avail(priv->buf) != 0) {
 895                         schedule_delayed_work(&priv->delayed_write_work, 0);
 896                         resubmit = 0;
 897                 }
 898                 spin_unlock_irqrestore(&priv->lock, flags);
 899         }
 900
 901         if (resubmit) {
 902                 int result;
 903
 904 /*              dbg("%s(): submitting interrupt urb", __func__); */
 905                 urb->dev = port->serial->dev;
 906                 result = usb_submit_urb(urb, GFP_ATOMIC);
 907                 if (result != 0) {
 908                         dev_err(&urb->dev->dev,
 909                                         "%s(): usb_submit_urb() failed with"
 910                                         " error %d\n", __func__, result);
 911                 }
 912         }
 913 }
 914
 915 static void oti6858_read_bulk_callback(struct urb *urb)
 916 {
 917         struct usb_serial_port *port =  urb->context;
 918         struct oti6858_private *priv = usb_get_serial_port_data(port);
 919         struct tty_struct *tty;
 920         unsigned char *data = urb->transfer_buffer;
 921         unsigned long flags;
 922         int status = urb->status;
 923         int result;
 924
 925         dbg("%s(port = %d, status = %d)",
 926                                 __func__, port->number, status);
 927
 928         spin_lock_irqsave(&priv->lock, flags);
 929         priv->flags.read_urb_in_use = 0;
 930         spin_unlock_irqrestore(&priv->lock, flags);
 931
 932         if (status != 0) {
 933                 if (!port->port.count) {
 934                         dbg("%s(): port is closed, exiting", __func__);
 935                         return;
 936                 }
 937                 /*
 938                 if (status == -EPROTO) {
 939                         * PL2303 mysteriously fails with -EPROTO reschedule
 940                            the read *
 941                         dbg("%s - caught -EPROTO, resubmitting the urb",
 942                                                                 __func__);
 943                         result = usb_submit_urb(urb, GFP_ATOMIC);
 944                         if (result)
 945                                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __func__, result);
 946                         return;
 947                 }
 948                 */
 949                 dbg("%s(): unable to handle the error, exiting", __func__);
 950                 return;
 951         }
 952
 953         tty = tty_port_tty_get(&port->port);
 954         if (tty != NULL && urb->actual_length > 0) {
 955                 tty_insert_flip_string(tty, data, urb->actual_length);
 956                 tty_flip_buffer_push(tty);
 957         }
 958         tty_kref_put(tty);
 959
 960         /* schedule the interrupt urb if we are still open */
 961         if (port->port.count != 0) {
 962                 port->interrupt_in_urb->dev = port->serial->dev;
 963                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 964                 if (result != 0) {
 965                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 966                                         " error %d\n", __func__, result);
 967                 }
 968         }
 969 }
 970
 971 static void oti6858_write_bulk_callback(struct urb *urb)
 972 {
 973         struct usb_serial_port *port =  urb->context;
 974         struct oti6858_private *priv = usb_get_serial_port_data(port);
 975         int status = urb->status;
 976         int result;
 977
 978         dbg("%s(port = %d, status = %d)",
 979                                 __func__, port->number, status);
 980
 981         switch (status) {
 982         case 0:
 983                 /* success */
 984                 break;
 985         case -ECONNRESET:
 986         case -ENOENT:
 987         case -ESHUTDOWN:
 988                 /* this urb is terminated, clean up */
 989                 dbg("%s(): urb shutting down with status: %d",
 990                                         __func__, status);
 991                 priv->flags.write_urb_in_use = 0;
 992                 return;
 993         default:
 994                 /* error in the urb, so we have to resubmit it */
 995                 dbg("%s(): nonzero write bulk status received: %d",
 996                                         __func__, status);
 997                 dbg("%s(): overflow in write", __func__);
 998
 999                 port->write_urb->transfer_buffer_length = 1;
1000                 port->write_urb->dev = port->serial->dev;
1001                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1002                 if (result) {
1003                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
1004                                         " error %d\n", __func__, result);
1005                 } else {
1006                         return;
1007                 }
1008         }
1009
1010         priv->flags.write_urb_in_use = 0;
1011
1012         /* schedule the interrupt urb if we are still open */
1013         port->interrupt_in_urb->dev = port->serial->dev;
1014         dbg("%s(): submitting interrupt urb", __func__);
1015         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1016         if (result != 0) {
1017                 dev_err(&port->dev, "%s(): failed submitting int urb,"
1018                                         " error %d\n", __func__, result);
1019         }
1020 }
1021
1022
1023 /*
1024  * oti6858_buf_alloc
1025  *
1026  * Allocate a circular buffer and all associated memory.
1027  */
1028 static struct oti6858_buf *oti6858_buf_alloc(unsigned int size)
1029 {
1030         struct oti6858_buf *pb;
1031
1032         if (size == 0)
1033                 return NULL;
1034
1035         pb = kmalloc(sizeof(struct oti6858_buf), GFP_KERNEL);
1036         if (pb == NULL)
1037                 return NULL;
1038
1039         pb->buf_buf = kmalloc(size, GFP_KERNEL);
1040         if (pb->buf_buf == NULL) {
1041                 kfree(pb);
1042                 return NULL;
1043         }
1044
1045         pb->buf_size = size;
1046         pb->buf_get = pb->buf_put = pb->buf_buf;
1047
1048         return pb;
1049 }
1050
1051 /*
1052  * oti6858_buf_free
1053  *
1054  * Free the buffer and all associated memory.
1055  */
1056 static void oti6858_buf_free(struct oti6858_buf *pb)
1057 {
1058         if (pb) {
1059                 kfree(pb->buf_buf);
1060                 kfree(pb);
1061         }
1062 }
1063
1064 /*
1065  * oti6858_buf_clear
1066  *
1067  * Clear out all data in the circular buffer.
1068  */
1069 static void oti6858_buf_clear(struct oti6858_buf *pb)
1070 {
1071         if (pb != NULL) {
1072                 /* equivalent to a get of all data available */
1073                 pb->buf_get = pb->buf_put;
1074         }
1075 }
1076
1077 /*
1078  * oti6858_buf_data_avail
1079  *
1080  * Return the number of bytes of data available in the circular
1081  * buffer.
1082  */
1083 static unsigned int oti6858_buf_data_avail(struct oti6858_buf *pb)
1084 {
1085         if (pb == NULL)
1086                 return 0;
1087         return (pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size;
1088 }
1089
1090 /*
1091  * oti6858_buf_space_avail
1092  *
1093  * Return the number of bytes of space available in the circular
1094  * buffer.
1095  */
1096 static unsigned int oti6858_buf_space_avail(struct oti6858_buf *pb)
1097 {
1098         if (pb == NULL)
1099                 return 0;
1100         return (pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size;
1101 }
1102
1103 /*
1104  * oti6858_buf_put
1105  *
1106  * Copy data data from a user buffer and put it into the circular buffer.
1107  * Restrict to the amount of space available.
1108  *
1109  * Return the number of bytes copied.
1110  */
1111 static unsigned int oti6858_buf_put(struct oti6858_buf *pb, const char *buf,
1112                                         unsigned int count)
1113 {
1114         unsigned int len;
1115
1116         if (pb == NULL)
1117                 return 0;
1118
1119         len  = oti6858_buf_space_avail(pb);
1120         if (count > len)
1121                 count = len;
1122
1123         if (count == 0)
1124                 return 0;
1125
1126         len = pb->buf_buf + pb->buf_size - pb->buf_put;
1127         if (count > len) {
1128                 memcpy(pb->buf_put, buf, len);
1129                 memcpy(pb->buf_buf, buf+len, count - len);
1130                 pb->buf_put = pb->buf_buf + count - len;
1131         } else {
1132                 memcpy(pb->buf_put, buf, count);
1133                 if (count < len)
1134                         pb->buf_put += count;
1135                 else /* count == len */
1136                         pb->buf_put = pb->buf_buf;
1137         }
1138
1139         return count;
1140 }
1141
1142 /*
1143  * oti6858_buf_get
1144  *
1145  * Get data from the circular buffer and copy to the given buffer.
1146  * Restrict to the amount of data available.
1147  *
1148  * Return the number of bytes copied.
1149  */
1150 static unsigned int oti6858_buf_get(struct oti6858_buf *pb, char *buf,
1151                                         unsigned int count)
1152 {
1153         unsigned int len;
1154
1155         if (pb == NULL)
1156                 return 0;
1157
1158         len = oti6858_buf_data_avail(pb);
1159         if (count > len)
1160                 count = len;
1161
1162         if (count == 0)
1163                 return 0;
1164
1165         len = pb->buf_buf + pb->buf_size - pb->buf_get;
1166         if (count > len) {
1167                 memcpy(buf, pb->buf_get, len);
1168                 memcpy(buf+len, pb->buf_buf, count - len);
1169                 pb->buf_get = pb->buf_buf + count - len;
1170         } else {
1171                 memcpy(buf, pb->buf_get, count);
1172                 if (count < len)
1173                         pb->buf_get += count;
1174                 else /* count == len */
1175                         pb->buf_get = pb->buf_buf;
1176         }
1177
1178         return count;
1179 }
1180
1181 /* module description and (de)initialization */
1182
1183 static int __init oti6858_init(void)
1184 {
1185         int retval;
1186
1187         retval = usb_serial_register(&oti6858_device);
1188         if (retval == 0) {
1189                 retval = usb_register(&oti6858_driver);
1190                 if (retval)
1191                         usb_serial_deregister(&oti6858_device);
1192         }
1193         return retval;
1194 }
1195
1196 static void __exit oti6858_exit(void)
1197 {
1198         usb_deregister(&oti6858_driver);
1199         usb_serial_deregister(&oti6858_device);
1200 }
1201
1202 module_init(oti6858_init);
1203 module_exit(oti6858_exit);
1204
1205 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
1206 MODULE_AUTHOR(OTI6858_AUTHOR);
1207 MODULE_VERSION(OTI6858_VERSION);
1208 MODULE_LICENSE("GPL");
1209
1210 module_param(debug, bool, S_IRUGO | S_IWUSR);
1211 MODULE_PARM_DESC(debug, "enable debug output");
1212