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 const struct usb_device_id id_table[] = {
  62         { USB_DEVICE(OTI6858_VENDOR_ID, OTI6858_PRODUCT_ID) },
  63         { }
  64 };
  65
  66 MODULE_DEVICE_TABLE(usb, id_table);
  67
  68 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, struct usb_serial_port *port);
 145 static void oti6858_close(struct usb_serial_port *port);
 146 static void oti6858_set_termios(struct tty_struct *tty,
 147                         struct usb_serial_port *port, struct ktermios *old);
 148 static void oti6858_init_termios(struct tty_struct *tty);
 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         .init_termios =         oti6858_init_termios,
 190         .tiocmget =             oti6858_tiocmget,
 191         .tiocmset =             oti6858_tiocmset,
 192         .read_bulk_callback =   oti6858_read_bulk_callback,
 193         .read_int_callback =    oti6858_read_int_callback,
 194         .write_bulk_callback =  oti6858_write_bulk_callback,
 195         .write_room =           oti6858_write_room,
 196         .chars_in_buffer =      oti6858_chars_in_buffer,
 197         .attach =               oti6858_startup,
 198         .release =              oti6858_release,
 199 };
 200
 201 struct oti6858_private {
 202         spinlock_t lock;
 203
 204         struct oti6858_buf *buf;
 205         struct oti6858_control_pkt status;
 206
 207         struct {
 208                 u8 read_urb_in_use;
 209                 u8 write_urb_in_use;
 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_KERNEL);
 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 static 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         u8 *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                 allow = kmalloc(1, GFP_KERNEL);
 325                 if (!allow) {
 326                         dev_err(&port->dev, "%s(): kmalloc failed\n",
 327                                         __func__);
 328                         return;
 329                 }
 330                 result = usb_control_msg(port->serial->dev,
 331                                 usb_rcvctrlpipe(port->serial->dev, 0),
 332                                 OTI6858_REQ_T_CHECK_TXBUFF,
 333                                 OTI6858_REQ_CHECK_TXBUFF,
 334                                 count, 0, allow, 1, 100);
 335                 if (result != 1 || *allow != 0)
 336                         count = 0;
 337                 kfree(allow);
 338         }
 339
 340         if (count == 0) {
 341                 priv->flags.write_urb_in_use = 0;
 342
 343                 dbg("%s(): submitting interrupt urb", __func__);
 344                 port->interrupt_in_urb->dev = port->serial->dev;
 345                 result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
 346                 if (result != 0) {
 347                         dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 348                                 " with error %d\n", __func__, result);
 349                 }
 350                 return;
 351         }
 352
 353         spin_lock_irqsave(&priv->lock, flags);
 354         oti6858_buf_get(priv->buf, port->write_urb->transfer_buffer, count);
 355         spin_unlock_irqrestore(&priv->lock, flags);
 356
 357         port->write_urb->transfer_buffer_length = count;
 358         port->write_urb->dev = port->serial->dev;
 359         result = usb_submit_urb(port->write_urb, GFP_NOIO);
 360         if (result != 0) {
 361                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 362                                " with error %d\n", __func__, result);
 363                 priv->flags.write_urb_in_use = 0;
 364         }
 365
 366         usb_serial_port_softint(port);
 367 }
 368
 369 static int oti6858_startup(struct usb_serial *serial)
 370 {
 371         struct usb_serial_port *port = serial->port[0];
 372         struct oti6858_private *priv;
 373         int i;
 374
 375         for (i = 0; i < serial->num_ports; ++i) {
 376                 priv = kzalloc(sizeof(struct oti6858_private), GFP_KERNEL);
 377                 if (!priv)
 378                         break;
 379                 priv->buf = oti6858_buf_alloc(PL2303_BUF_SIZE);
 380                 if (priv->buf == NULL) {
 381                         kfree(priv);
 382                         break;
 383                 }
 384
 385                 spin_lock_init(&priv->lock);
 386                 init_waitqueue_head(&priv->intr_wait);
 387 /*              INIT_WORK(&priv->setup_work, setup_line, serial->port[i]); */
 388 /*              INIT_WORK(&priv->write_work, send_data, serial->port[i]); */
 389                 priv->port = port;
 390                 INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 391                 INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 392
 393                 usb_set_serial_port_data(serial->port[i], priv);
 394         }
 395         if (i == serial->num_ports)
 396                 return 0;
 397
 398         for (--i; i >= 0; --i) {
 399                 priv = usb_get_serial_port_data(serial->port[i]);
 400                 oti6858_buf_free(priv->buf);
 401                 kfree(priv);
 402                 usb_set_serial_port_data(serial->port[i], NULL);
 403         }
 404         return -ENOMEM;
 405 }
 406
 407 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 408                         const unsigned char *buf, int count)
 409 {
 410         struct oti6858_private *priv = usb_get_serial_port_data(port);
 411         unsigned long flags;
 412
 413         dbg("%s(port = %d, count = %d)", __func__, port->number, count);
 414
 415         if (!count)
 416                 return count;
 417
 418         spin_lock_irqsave(&priv->lock, flags);
 419         count = oti6858_buf_put(priv->buf, buf, count);
 420         spin_unlock_irqrestore(&priv->lock, flags);
 421
 422         return count;
 423 }
 424
 425 static int oti6858_write_room(struct tty_struct *tty)
 426 {
 427         struct usb_serial_port *port = tty->driver_data;
 428         struct oti6858_private *priv = usb_get_serial_port_data(port);
 429         int room = 0;
 430         unsigned long flags;
 431
 432         dbg("%s(port = %d)", __func__, port->number);
 433
 434         spin_lock_irqsave(&priv->lock, flags);
 435         room = oti6858_buf_space_avail(priv->buf);
 436         spin_unlock_irqrestore(&priv->lock, flags);
 437
 438         return room;
 439 }
 440
 441 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 442 {
 443         struct usb_serial_port *port = tty->driver_data;
 444         struct oti6858_private *priv = usb_get_serial_port_data(port);
 445         int chars = 0;
 446         unsigned long flags;
 447
 448         dbg("%s(port = %d)", __func__, port->number);
 449
 450         spin_lock_irqsave(&priv->lock, flags);
 451         chars = oti6858_buf_data_avail(priv->buf);
 452         spin_unlock_irqrestore(&priv->lock, flags);
 453
 454         return chars;
 455 }
 456
 457 static void oti6858_init_termios(struct tty_struct *tty)
 458 {
 459         *(tty->termios) = tty_std_termios;
 460         tty->termios->c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
 461         tty->termios->c_ispeed = 38400;
 462         tty->termios->c_ospeed = 38400;
 463 }
 464
 465 static void oti6858_set_termios(struct tty_struct *tty,
 466                 struct usb_serial_port *port, struct ktermios *old_termios)
 467 {
 468         struct oti6858_private *priv = usb_get_serial_port_data(port);
 469         unsigned long flags;
 470         unsigned int cflag;
 471         u8 frame_fmt, control;
 472         __le16 divisor;
 473         int br;
 474
 475         dbg("%s(port = %d)", __func__, port->number);
 476
 477         if (!tty) {
 478                 dbg("%s(): no tty structures", __func__);
 479                 return;
 480         }
 481
 482         cflag = tty->termios->c_cflag;
 483
 484         spin_lock_irqsave(&priv->lock, flags);
 485         divisor = priv->pending_setup.divisor;
 486         frame_fmt = priv->pending_setup.frame_fmt;
 487         control = priv->pending_setup.control;
 488         spin_unlock_irqrestore(&priv->lock, flags);
 489
 490         frame_fmt &= ~FMT_DATA_BITS_MASK;
 491         switch (cflag & CSIZE) {
 492         case CS5:
 493                 frame_fmt |= FMT_DATA_BITS_5;
 494                 break;
 495         case CS6:
 496                 frame_fmt |= FMT_DATA_BITS_6;
 497                 break;
 498         case CS7:
 499                 frame_fmt |= FMT_DATA_BITS_7;
 500                 break;
 501         default:
 502         case CS8:
 503                 frame_fmt |= FMT_DATA_BITS_8;
 504                 break;
 505         }
 506
 507         /* manufacturer claims that this device can work with baud rates
 508          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 509          * guarantee that any other baud rate will work (especially
 510          * the higher ones)
 511          */
 512         br = tty_get_baud_rate(tty);
 513         if (br == 0) {
 514                 divisor = 0;
 515         } else {
 516                 int real_br;
 517                 int new_divisor;
 518                 br = min(br, OTI6858_MAX_BAUD_RATE);
 519
 520                 new_divisor = (96000000 + 8 * br) / (16 * br);
 521                 real_br = 96000000 / (16 * new_divisor);
 522                 divisor = cpu_to_le16(new_divisor);
 523                 tty_encode_baud_rate(tty, real_br, real_br);
 524         }
 525
 526         frame_fmt &= ~FMT_STOP_BITS_MASK;
 527         if ((cflag & CSTOPB) != 0)
 528                 frame_fmt |= FMT_STOP_BITS_2;
 529         else
 530                 frame_fmt |= FMT_STOP_BITS_1;
 531
 532         frame_fmt &= ~FMT_PARITY_MASK;
 533         if ((cflag & PARENB) != 0) {
 534                 if ((cflag & PARODD) != 0)
 535                         frame_fmt |= FMT_PARITY_ODD;
 536                 else
 537                         frame_fmt |= FMT_PARITY_EVEN;
 538         } else {
 539                 frame_fmt |= FMT_PARITY_NONE;
 540         }
 541
 542         control &= ~CONTROL_MASK;
 543         if ((cflag & CRTSCTS) != 0)
 544                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 545
 546         /* change control lines if we are switching to or from B0 */
 547         /* FIXME:
 548         spin_lock_irqsave(&priv->lock, flags);
 549         control = priv->line_control;
 550         if ((cflag & CBAUD) == B0)
 551                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 552         else
 553                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 554         if (control != priv->line_control) {
 555                 control = priv->line_control;
 556                 spin_unlock_irqrestore(&priv->lock, flags);
 557                 set_control_lines(serial->dev, control);
 558         } else {
 559                 spin_unlock_irqrestore(&priv->lock, flags);
 560         }
 561         */
 562
 563         spin_lock_irqsave(&priv->lock, flags);
 564         if (divisor != priv->pending_setup.divisor
 565                         || control != priv->pending_setup.control
 566                         || frame_fmt != priv->pending_setup.frame_fmt) {
 567                 priv->pending_setup.divisor = divisor;
 568                 priv->pending_setup.control = control;
 569                 priv->pending_setup.frame_fmt = frame_fmt;
 570         }
 571         spin_unlock_irqrestore(&priv->lock, flags);
 572 }
 573
 574 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
 575 {
 576         struct oti6858_private *priv = usb_get_serial_port_data(port);
 577         struct ktermios tmp_termios;
 578         struct usb_serial *serial = port->serial;
 579         struct oti6858_control_pkt *buf;
 580         unsigned long flags;
 581         int result;
 582
 583         dbg("%s(port = %d)", __func__, port->number);
 584
 585         usb_clear_halt(serial->dev, port->write_urb->pipe);
 586         usb_clear_halt(serial->dev, port->read_urb->pipe);
 587
 588         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 589         if (buf == NULL) {
 590                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 591                 return -ENOMEM;
 592         }
 593
 594         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 595                                 OTI6858_REQ_T_GET_STATUS,
 596                                 OTI6858_REQ_GET_STATUS,
 597                                 0, 0,
 598                                 buf, OTI6858_CTRL_PKT_SIZE,
 599                                 100);
 600         if (result != OTI6858_CTRL_PKT_SIZE) {
 601                 /* assume default (after power-on reset) values */
 602                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 603                 buf->frame_fmt = 0x03;  /* 8N1 */
 604                 buf->something = 0x43;
 605                 buf->control = 0x4c;    /* DTR, RTS */
 606                 buf->tx_status = 0x00;
 607                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 608                 buf->rx_bytes_avail = 0x00;
 609         }
 610
 611         spin_lock_irqsave(&priv->lock, flags);
 612         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 613         priv->pending_setup.divisor = buf->divisor;
 614         priv->pending_setup.frame_fmt = buf->frame_fmt;
 615         priv->pending_setup.control = buf->control;
 616         spin_unlock_irqrestore(&priv->lock, flags);
 617         kfree(buf);
 618
 619         dbg("%s(): submitting interrupt urb", __func__);
 620         port->interrupt_in_urb->dev = serial->dev;
 621         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 622         if (result != 0) {
 623                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 624                                " with error %d\n", __func__, result);
 625                 oti6858_close(port);
 626                 return -EPROTO;
 627         }
 628
 629         /* setup termios */
 630         if (tty)
 631                 oti6858_set_termios(tty, port, &tmp_termios);
 632         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 633         return 0;
 634 }
 635
 636 static void oti6858_close(struct usb_serial_port *port)
 637 {
 638         struct oti6858_private *priv = usb_get_serial_port_data(port);
 639         unsigned long flags;
 640
 641         dbg("%s(port = %d)", __func__, port->number);
 642
 643         spin_lock_irqsave(&priv->lock, flags);
 644         /* clear out any remaining data in the buffer */
 645         oti6858_buf_clear(priv->buf);
 646         spin_unlock_irqrestore(&priv->lock, flags);
 647
 648         dbg("%s(): after buf_clear()", __func__);
 649
 650         /* cancel scheduled setup */
 651         cancel_delayed_work(&priv->delayed_setup_work);
 652         cancel_delayed_work(&priv->delayed_write_work);
 653         flush_scheduled_work();
 654
 655         /* shutdown our urbs */
 656         dbg("%s(): shutting down urbs", __func__);
 657         usb_kill_urb(port->write_urb);
 658         usb_kill_urb(port->read_urb);
 659         usb_kill_urb(port->interrupt_in_urb);
 660 }
 661
 662 static int oti6858_tiocmset(struct tty_struct *tty, struct file *file,
 663                                 unsigned int set, unsigned int clear)
 664 {
 665         struct usb_serial_port *port = tty->driver_data;
 666         struct oti6858_private *priv = usb_get_serial_port_data(port);
 667         unsigned long flags;
 668         u8 control;
 669
 670         dbg("%s(port = %d, set = 0x%08x, clear = 0x%08x)",
 671                                 __func__, port->number, set, clear);
 672
 673         if (!usb_get_intfdata(port->serial->interface))
 674                 return -ENODEV;
 675
 676         /* FIXME: check if this is correct (active high/low) */
 677         spin_lock_irqsave(&priv->lock, flags);
 678         control = priv->pending_setup.control;
 679         if ((set & TIOCM_RTS) != 0)
 680                 control |= CONTROL_RTS_HIGH;
 681         if ((set & TIOCM_DTR) != 0)
 682                 control |= CONTROL_DTR_HIGH;
 683         if ((clear & TIOCM_RTS) != 0)
 684                 control &= ~CONTROL_RTS_HIGH;
 685         if ((clear & TIOCM_DTR) != 0)
 686                 control &= ~CONTROL_DTR_HIGH;
 687
 688         if (control != priv->pending_setup.control)
 689                 priv->pending_setup.control = control;
 690
 691         spin_unlock_irqrestore(&priv->lock, flags);
 692         return 0;
 693 }
 694
 695 static int oti6858_tiocmget(struct tty_struct *tty, struct file *file)
 696 {
 697         struct usb_serial_port *port = tty->driver_data;
 698         struct oti6858_private *priv = usb_get_serial_port_data(port);
 699         unsigned long flags;
 700         unsigned pin_state;
 701         unsigned result = 0;
 702
 703         dbg("%s(port = %d)", __func__, port->number);
 704
 705         if (!usb_get_intfdata(port->serial->interface))
 706                 return -ENODEV;
 707
 708         spin_lock_irqsave(&priv->lock, flags);
 709         pin_state = priv->status.pin_state & PIN_MASK;
 710         spin_unlock_irqrestore(&priv->lock, flags);
 711
 712         /* FIXME: check if this is correct (active high/low) */
 713         if ((pin_state & PIN_RTS) != 0)
 714                 result |= TIOCM_RTS;
 715         if ((pin_state & PIN_CTS) != 0)
 716                 result |= TIOCM_CTS;
 717         if ((pin_state & PIN_DSR) != 0)
 718                 result |= TIOCM_DSR;
 719         if ((pin_state & PIN_DTR) != 0)
 720                 result |= TIOCM_DTR;
 721         if ((pin_state & PIN_RI) != 0)
 722                 result |= TIOCM_RI;
 723         if ((pin_state & PIN_DCD) != 0)
 724                 result |= TIOCM_CD;
 725
 726         dbg("%s() = 0x%08x", __func__, result);
 727
 728         return result;
 729 }
 730
 731 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 732 {
 733         struct oti6858_private *priv = usb_get_serial_port_data(port);
 734         unsigned long flags;
 735         unsigned int prev, status;
 736         unsigned int changed;
 737
 738         spin_lock_irqsave(&priv->lock, flags);
 739         prev = priv->status.pin_state;
 740         spin_unlock_irqrestore(&priv->lock, flags);
 741
 742         while (1) {
 743                 wait_event_interruptible(priv->intr_wait,
 744                                         priv->status.pin_state != prev);
 745                 if (signal_pending(current))
 746                         return -ERESTARTSYS;
 747
 748                 spin_lock_irqsave(&priv->lock, flags);
 749                 status = priv->status.pin_state & PIN_MASK;
 750                 spin_unlock_irqrestore(&priv->lock, flags);
 751
 752                 changed = prev ^ status;
 753                 /* FIXME: check if this is correct (active high/low) */
 754                 if (((arg & TIOCM_RNG) && (changed & PIN_RI)) ||
 755                     ((arg & TIOCM_DSR) && (changed & PIN_DSR)) ||
 756                     ((arg & TIOCM_CD)  && (changed & PIN_DCD)) ||
 757                     ((arg & TIOCM_CTS) && (changed & PIN_CTS)))
 758                         return 0;
 759                 prev = status;
 760         }
 761
 762         /* NOTREACHED */
 763         return 0;
 764 }
 765
 766 static int oti6858_ioctl(struct tty_struct *tty, struct file *file,
 767                         unsigned int cmd, unsigned long arg)
 768 {
 769         struct usb_serial_port *port = tty->driver_data;
 770
 771         dbg("%s(port = %d, cmd = 0x%04x, arg = 0x%08lx)",
 772                                 __func__, port->number, cmd, arg);
 773
 774         switch (cmd) {
 775         case TIOCMIWAIT:
 776                 dbg("%s(): TIOCMIWAIT", __func__);
 777                 return wait_modem_info(port, arg);
 778         default:
 779                 dbg("%s(): 0x%04x not supported", __func__, cmd);
 780                 break;
 781         }
 782         return -ENOIOCTLCMD;
 783 }
 784
 785
 786 static void oti6858_release(struct usb_serial *serial)
 787 {
 788         struct oti6858_private *priv;
 789         int i;
 790
 791         dbg("%s()", __func__);
 792
 793         for (i = 0; i < serial->num_ports; ++i) {
 794                 priv = usb_get_serial_port_data(serial->port[i]);
 795                 if (priv) {
 796                         oti6858_buf_free(priv->buf);
 797                         kfree(priv);
 798                 }
 799         }
 800 }
 801
 802 static void oti6858_read_int_callback(struct urb *urb)
 803 {
 804         struct usb_serial_port *port =  urb->context;
 805         struct oti6858_private *priv = usb_get_serial_port_data(port);
 806         int transient = 0, can_recv = 0, resubmit = 1;
 807         int status = urb->status;
 808
 809         dbg("%s(port = %d, status = %d)",
 810                                 __func__, port->number, status);
 811
 812         switch (status) {
 813         case 0:
 814                 /* success */
 815                 break;
 816         case -ECONNRESET:
 817         case -ENOENT:
 818         case -ESHUTDOWN:
 819                 /* this urb is terminated, clean up */
 820                 dbg("%s(): urb shutting down with status: %d",
 821                                         __func__, status);
 822                 return;
 823         default:
 824                 dbg("%s(): nonzero urb status received: %d",
 825                                         __func__, status);
 826                 break;
 827         }
 828
 829         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 830                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 831                 unsigned long flags;
 832
 833                 spin_lock_irqsave(&priv->lock, flags);
 834
 835                 if (!priv->transient) {
 836                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 837                                 if (xs->rx_bytes_avail == 0) {
 838                                         priv->transient = 4;
 839                                         priv->setup_done = 0;
 840                                         resubmit = 0;
 841                                         dbg("%s(): scheduling setup_line()",
 842                                             __func__);
 843                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 844                                 }
 845                         }
 846                 } else {
 847                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 848                                 priv->transient = 0;
 849                         } else if (!priv->setup_done) {
 850                                 resubmit = 0;
 851                         } else if (--priv->transient == 0) {
 852                                 if (xs->rx_bytes_avail == 0) {
 853                                         priv->transient = 4;
 854                                         priv->setup_done = 0;
 855                                         resubmit = 0;
 856                                         dbg("%s(): scheduling setup_line()",
 857                                             __func__);
 858                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 859                                 }
 860                         }
 861                 }
 862
 863                 if (!priv->transient) {
 864                         if (xs->pin_state != priv->status.pin_state)
 865                                 wake_up_interruptible(&priv->intr_wait);
 866                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 867                 }
 868
 869                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 870                         can_recv = xs->rx_bytes_avail;
 871                         priv->flags.read_urb_in_use = 1;
 872                 }
 873
 874                 transient = priv->transient;
 875                 spin_unlock_irqrestore(&priv->lock, flags);
 876         }
 877
 878         if (can_recv) {
 879                 int result;
 880
 881                 port->read_urb->dev = port->serial->dev;
 882                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 883                 if (result != 0) {
 884                         priv->flags.read_urb_in_use = 0;
 885                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 886                                         " error %d\n", __func__, result);
 887                 } else {
 888                         resubmit = 0;
 889                 }
 890         } else if (!transient) {
 891                 unsigned long flags;
 892
 893                 spin_lock_irqsave(&priv->lock, flags);
 894                 if (priv->flags.write_urb_in_use == 0
 895                                 && oti6858_buf_data_avail(priv->buf) != 0) {
 896                         schedule_delayed_work(&priv->delayed_write_work, 0);
 897                         resubmit = 0;
 898                 }
 899                 spin_unlock_irqrestore(&priv->lock, flags);
 900         }
 901
 902         if (resubmit) {
 903                 int result;
 904
 905 /*              dbg("%s(): submitting interrupt urb", __func__); */
 906                 urb->dev = port->serial->dev;
 907                 result = usb_submit_urb(urb, GFP_ATOMIC);
 908                 if (result != 0) {
 909                         dev_err(&urb->dev->dev,
 910                                         "%s(): usb_submit_urb() failed with"
 911                                         " error %d\n", __func__, result);
 912                 }
 913         }
 914 }
 915
 916 static void oti6858_read_bulk_callback(struct urb *urb)
 917 {
 918         struct usb_serial_port *port =  urb->context;
 919         struct oti6858_private *priv = usb_get_serial_port_data(port);
 920         struct tty_struct *tty;
 921         unsigned char *data = urb->transfer_buffer;
 922         unsigned long flags;
 923         int status = urb->status;
 924         int result;
 925
 926         dbg("%s(port = %d, status = %d)",
 927                                 __func__, port->number, status);
 928
 929         spin_lock_irqsave(&priv->lock, flags);
 930         priv->flags.read_urb_in_use = 0;
 931         spin_unlock_irqrestore(&priv->lock, flags);
 932
 933         if (status != 0) {
 934                 /*
 935                 if (status == -EPROTO) {
 936                         * PL2303 mysteriously fails with -EPROTO reschedule
 937                            the read *
 938                         dbg("%s - caught -EPROTO, resubmitting the urb",
 939                                                                 __func__);
 940                         result = usb_submit_urb(urb, GFP_ATOMIC);
 941                         if (result)
 942                                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __func__, result);
 943                         return;
 944                 }
 945                 */
 946                 dbg("%s(): unable to handle the error, exiting", __func__);
 947                 return;
 948         }
 949
 950         tty = tty_port_tty_get(&port->port);
 951         if (tty != NULL && urb->actual_length > 0) {
 952                 tty_insert_flip_string(tty, data, urb->actual_length);
 953                 tty_flip_buffer_push(tty);
 954         }
 955         tty_kref_put(tty);
 956
 957         /* schedule the interrupt urb */
 958         port->interrupt_in_urb->dev = port->serial->dev;
 959         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 960         if (result != 0 && result != -EPERM) {
 961                 dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 962                                 " error %d\n", __func__, result);
 963         }
 964 }
 965
 966 static void oti6858_write_bulk_callback(struct urb *urb)
 967 {
 968         struct usb_serial_port *port =  urb->context;
 969         struct oti6858_private *priv = usb_get_serial_port_data(port);
 970         int status = urb->status;
 971         int result;
 972
 973         dbg("%s(port = %d, status = %d)",
 974                                 __func__, port->number, status);
 975
 976         switch (status) {
 977         case 0:
 978                 /* success */
 979                 break;
 980         case -ECONNRESET:
 981         case -ENOENT:
 982         case -ESHUTDOWN:
 983                 /* this urb is terminated, clean up */
 984                 dbg("%s(): urb shutting down with status: %d",
 985                                         __func__, status);
 986                 priv->flags.write_urb_in_use = 0;
 987                 return;
 988         default:
 989                 /* error in the urb, so we have to resubmit it */
 990                 dbg("%s(): nonzero write bulk status received: %d",
 991                                         __func__, status);
 992                 dbg("%s(): overflow in write", __func__);
 993
 994                 port->write_urb->transfer_buffer_length = 1;
 995                 port->write_urb->dev = port->serial->dev;
 996                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 997                 if (result) {
 998                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 999                                         " error %d\n", __func__, result);
1000                 } else {
1001                         return;
1002                 }
1003         }
1004
1005         priv->flags.write_urb_in_use = 0;
1006
1007         /* schedule the interrupt urb if we are still open */
1008         port->interrupt_in_urb->dev = port->serial->dev;
1009         dbg("%s(): submitting interrupt urb", __func__);
1010         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1011         if (result != 0) {
1012                 dev_err(&port->dev, "%s(): failed submitting int urb,"
1013                                         " error %d\n", __func__, result);
1014         }
1015 }
1016
1017
1018 /*
1019  * oti6858_buf_alloc
1020  *
1021  * Allocate a circular buffer and all associated memory.
1022  */
1023 static struct oti6858_buf *oti6858_buf_alloc(unsigned int size)
1024 {
1025         struct oti6858_buf *pb;
1026
1027         if (size == 0)
1028                 return NULL;
1029
1030         pb = kmalloc(sizeof(struct oti6858_buf), GFP_KERNEL);
1031         if (pb == NULL)
1032                 return NULL;
1033
1034         pb->buf_buf = kmalloc(size, GFP_KERNEL);
1035         if (pb->buf_buf == NULL) {
1036                 kfree(pb);
1037                 return NULL;
1038         }
1039
1040         pb->buf_size = size;
1041         pb->buf_get = pb->buf_put = pb->buf_buf;
1042
1043         return pb;
1044 }
1045
1046 /*
1047  * oti6858_buf_free
1048  *
1049  * Free the buffer and all associated memory.
1050  */
1051 static void oti6858_buf_free(struct oti6858_buf *pb)
1052 {
1053         if (pb) {
1054                 kfree(pb->buf_buf);
1055                 kfree(pb);
1056         }
1057 }
1058
1059 /*
1060  * oti6858_buf_clear
1061  *
1062  * Clear out all data in the circular buffer.
1063  */
1064 static void oti6858_buf_clear(struct oti6858_buf *pb)
1065 {
1066         if (pb != NULL) {
1067                 /* equivalent to a get of all data available */
1068                 pb->buf_get = pb->buf_put;
1069         }
1070 }
1071
1072 /*
1073  * oti6858_buf_data_avail
1074  *
1075  * Return the number of bytes of data available in the circular
1076  * buffer.
1077  */
1078 static unsigned int oti6858_buf_data_avail(struct oti6858_buf *pb)
1079 {
1080         if (pb == NULL)
1081                 return 0;
1082         return (pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size;
1083 }
1084
1085 /*
1086  * oti6858_buf_space_avail
1087  *
1088  * Return the number of bytes of space available in the circular
1089  * buffer.
1090  */
1091 static unsigned int oti6858_buf_space_avail(struct oti6858_buf *pb)
1092 {
1093         if (pb == NULL)
1094                 return 0;
1095         return (pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size;
1096 }
1097
1098 /*
1099  * oti6858_buf_put
1100  *
1101  * Copy data data from a user buffer and put it into the circular buffer.
1102  * Restrict to the amount of space available.
1103  *
1104  * Return the number of bytes copied.
1105  */
1106 static unsigned int oti6858_buf_put(struct oti6858_buf *pb, const char *buf,
1107                                         unsigned int count)
1108 {
1109         unsigned int len;
1110
1111         if (pb == NULL)
1112                 return 0;
1113
1114         len  = oti6858_buf_space_avail(pb);
1115         if (count > len)
1116                 count = len;
1117
1118         if (count == 0)
1119                 return 0;
1120
1121         len = pb->buf_buf + pb->buf_size - pb->buf_put;
1122         if (count > len) {
1123                 memcpy(pb->buf_put, buf, len);
1124                 memcpy(pb->buf_buf, buf+len, count - len);
1125                 pb->buf_put = pb->buf_buf + count - len;
1126         } else {
1127                 memcpy(pb->buf_put, buf, count);
1128                 if (count < len)
1129                         pb->buf_put += count;
1130                 else /* count == len */
1131                         pb->buf_put = pb->buf_buf;
1132         }
1133
1134         return count;
1135 }
1136
1137 /*
1138  * oti6858_buf_get
1139  *
1140  * Get data from the circular buffer and copy to the given buffer.
1141  * Restrict to the amount of data available.
1142  *
1143  * Return the number of bytes copied.
1144  */
1145 static unsigned int oti6858_buf_get(struct oti6858_buf *pb, char *buf,
1146                                         unsigned int count)
1147 {
1148         unsigned int len;
1149
1150         if (pb == NULL)
1151                 return 0;
1152
1153         len = oti6858_buf_data_avail(pb);
1154         if (count > len)
1155                 count = len;
1156
1157         if (count == 0)
1158                 return 0;
1159
1160         len = pb->buf_buf + pb->buf_size - pb->buf_get;
1161         if (count > len) {
1162                 memcpy(buf, pb->buf_get, len);
1163                 memcpy(buf+len, pb->buf_buf, count - len);
1164                 pb->buf_get = pb->buf_buf + count - len;
1165         } else {
1166                 memcpy(buf, pb->buf_get, count);
1167                 if (count < len)
1168                         pb->buf_get += count;
1169                 else /* count == len */
1170                         pb->buf_get = pb->buf_buf;
1171         }
1172
1173         return count;
1174 }
1175
1176 /* module description and (de)initialization */
1177
1178 static int __init oti6858_init(void)
1179 {
1180         int retval;
1181
1182         retval = usb_serial_register(&oti6858_device);
1183         if (retval == 0) {
1184                 retval = usb_register(&oti6858_driver);
1185                 if (retval)
1186                         usb_serial_deregister(&oti6858_device);
1187         }
1188         return retval;
1189 }
1190
1191 static void __exit oti6858_exit(void)
1192 {
1193         usb_deregister(&oti6858_driver);
1194         usb_serial_deregister(&oti6858_device);
1195 }
1196
1197 module_init(oti6858_init);
1198 module_exit(oti6858_exit);
1199
1200 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
1201 MODULE_AUTHOR(OTI6858_AUTHOR);
1202 MODULE_VERSION(OTI6858_VERSION);
1203 MODULE_LICENSE("GPL");
1204
1205 module_param(debug, bool, S_IRUGO | S_IWUSR);
1206 MODULE_PARM_DESC(debug, "enable debug output");
1207