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, 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 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         if (port->port.count != 1)
 589                 return 0;
 590
 591         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 592         if (buf == NULL) {
 593                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 594                 return -ENOMEM;
 595         }
 596
 597         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 598                                 OTI6858_REQ_T_GET_STATUS,
 599                                 OTI6858_REQ_GET_STATUS,
 600                                 0, 0,
 601                                 buf, OTI6858_CTRL_PKT_SIZE,
 602                                 100);
 603         if (result != OTI6858_CTRL_PKT_SIZE) {
 604                 /* assume default (after power-on reset) values */
 605                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 606                 buf->frame_fmt = 0x03;  /* 8N1 */
 607                 buf->something = 0x43;
 608                 buf->control = 0x4c;    /* DTR, RTS */
 609                 buf->tx_status = 0x00;
 610                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 611                 buf->rx_bytes_avail = 0x00;
 612         }
 613
 614         spin_lock_irqsave(&priv->lock, flags);
 615         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 616         priv->pending_setup.divisor = buf->divisor;
 617         priv->pending_setup.frame_fmt = buf->frame_fmt;
 618         priv->pending_setup.control = buf->control;
 619         spin_unlock_irqrestore(&priv->lock, flags);
 620         kfree(buf);
 621
 622         dbg("%s(): submitting interrupt urb", __func__);
 623         port->interrupt_in_urb->dev = serial->dev;
 624         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 625         if (result != 0) {
 626                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 627                                " with error %d\n", __func__, result);
 628                 oti6858_close(port);
 629                 return -EPROTO;
 630         }
 631
 632         /* setup termios */
 633         if (tty)
 634                 oti6858_set_termios(tty, port, &tmp_termios);
 635         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 636         return 0;
 637 }
 638
 639 static void oti6858_close(struct usb_serial_port *port)
 640 {
 641         struct oti6858_private *priv = usb_get_serial_port_data(port);
 642         unsigned long flags;
 643
 644         dbg("%s(port = %d)", __func__, port->number);
 645
 646         spin_lock_irqsave(&priv->lock, flags);
 647         /* clear out any remaining data in the buffer */
 648         oti6858_buf_clear(priv->buf);
 649         spin_unlock_irqrestore(&priv->lock, flags);
 650
 651         dbg("%s(): after buf_clear()", __func__);
 652
 653         /* cancel scheduled setup */
 654         cancel_delayed_work(&priv->delayed_setup_work);
 655         cancel_delayed_work(&priv->delayed_write_work);
 656         flush_scheduled_work();
 657
 658         /* shutdown our urbs */
 659         dbg("%s(): shutting down urbs", __func__);
 660         usb_kill_urb(port->write_urb);
 661         usb_kill_urb(port->read_urb);
 662         usb_kill_urb(port->interrupt_in_urb);
 663 }
 664
 665 static int oti6858_tiocmset(struct tty_struct *tty, struct file *file,
 666                                 unsigned int set, unsigned int clear)
 667 {
 668         struct usb_serial_port *port = tty->driver_data;
 669         struct oti6858_private *priv = usb_get_serial_port_data(port);
 670         unsigned long flags;
 671         u8 control;
 672
 673         dbg("%s(port = %d, set = 0x%08x, clear = 0x%08x)",
 674                                 __func__, port->number, set, clear);
 675
 676         if (!usb_get_intfdata(port->serial->interface))
 677                 return -ENODEV;
 678
 679         /* FIXME: check if this is correct (active high/low) */
 680         spin_lock_irqsave(&priv->lock, flags);
 681         control = priv->pending_setup.control;
 682         if ((set & TIOCM_RTS) != 0)
 683                 control |= CONTROL_RTS_HIGH;
 684         if ((set & TIOCM_DTR) != 0)
 685                 control |= CONTROL_DTR_HIGH;
 686         if ((clear & TIOCM_RTS) != 0)
 687                 control &= ~CONTROL_RTS_HIGH;
 688         if ((clear & TIOCM_DTR) != 0)
 689                 control &= ~CONTROL_DTR_HIGH;
 690
 691         if (control != priv->pending_setup.control)
 692                 priv->pending_setup.control = control;
 693
 694         spin_unlock_irqrestore(&priv->lock, flags);
 695         return 0;
 696 }
 697
 698 static int oti6858_tiocmget(struct tty_struct *tty, struct file *file)
 699 {
 700         struct usb_serial_port *port = tty->driver_data;
 701         struct oti6858_private *priv = usb_get_serial_port_data(port);
 702         unsigned long flags;
 703         unsigned pin_state;
 704         unsigned result = 0;
 705
 706         dbg("%s(port = %d)", __func__, port->number);
 707
 708         if (!usb_get_intfdata(port->serial->interface))
 709                 return -ENODEV;
 710
 711         spin_lock_irqsave(&priv->lock, flags);
 712         pin_state = priv->status.pin_state & PIN_MASK;
 713         spin_unlock_irqrestore(&priv->lock, flags);
 714
 715         /* FIXME: check if this is correct (active high/low) */
 716         if ((pin_state & PIN_RTS) != 0)
 717                 result |= TIOCM_RTS;
 718         if ((pin_state & PIN_CTS) != 0)
 719                 result |= TIOCM_CTS;
 720         if ((pin_state & PIN_DSR) != 0)
 721                 result |= TIOCM_DSR;
 722         if ((pin_state & PIN_DTR) != 0)
 723                 result |= TIOCM_DTR;
 724         if ((pin_state & PIN_RI) != 0)
 725                 result |= TIOCM_RI;
 726         if ((pin_state & PIN_DCD) != 0)
 727                 result |= TIOCM_CD;
 728
 729         dbg("%s() = 0x%08x", __func__, result);
 730
 731         return result;
 732 }
 733
 734 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 735 {
 736         struct oti6858_private *priv = usb_get_serial_port_data(port);
 737         unsigned long flags;
 738         unsigned int prev, status;
 739         unsigned int changed;
 740
 741         spin_lock_irqsave(&priv->lock, flags);
 742         prev = priv->status.pin_state;
 743         spin_unlock_irqrestore(&priv->lock, flags);
 744
 745         while (1) {
 746                 wait_event_interruptible(priv->intr_wait,
 747                                         priv->status.pin_state != prev);
 748                 if (signal_pending(current))
 749                         return -ERESTARTSYS;
 750
 751                 spin_lock_irqsave(&priv->lock, flags);
 752                 status = priv->status.pin_state & PIN_MASK;
 753                 spin_unlock_irqrestore(&priv->lock, flags);
 754
 755                 changed = prev ^ status;
 756                 /* FIXME: check if this is correct (active high/low) */
 757                 if (((arg & TIOCM_RNG) && (changed & PIN_RI)) ||
 758                     ((arg & TIOCM_DSR) && (changed & PIN_DSR)) ||
 759                     ((arg & TIOCM_CD)  && (changed & PIN_DCD)) ||
 760                     ((arg & TIOCM_CTS) && (changed & PIN_CTS)))
 761                         return 0;
 762                 prev = status;
 763         }
 764
 765         /* NOTREACHED */
 766         return 0;
 767 }
 768
 769 static int oti6858_ioctl(struct tty_struct *tty, struct file *file,
 770                         unsigned int cmd, unsigned long arg)
 771 {
 772         struct usb_serial_port *port = tty->driver_data;
 773
 774         dbg("%s(port = %d, cmd = 0x%04x, arg = 0x%08lx)",
 775                                 __func__, port->number, cmd, arg);
 776
 777         switch (cmd) {
 778         case TIOCMIWAIT:
 779                 dbg("%s(): TIOCMIWAIT", __func__);
 780                 return wait_modem_info(port, arg);
 781         default:
 782                 dbg("%s(): 0x%04x not supported", __func__, cmd);
 783                 break;
 784         }
 785         return -ENOIOCTLCMD;
 786 }
 787
 788
 789 static void oti6858_release(struct usb_serial *serial)
 790 {
 791         struct oti6858_private *priv;
 792         int i;
 793
 794         dbg("%s()", __func__);
 795
 796         for (i = 0; i < serial->num_ports; ++i) {
 797                 priv = usb_get_serial_port_data(serial->port[i]);
 798                 if (priv) {
 799                         oti6858_buf_free(priv->buf);
 800                         kfree(priv);
 801                 }
 802         }
 803 }
 804
 805 static void oti6858_read_int_callback(struct urb *urb)
 806 {
 807         struct usb_serial_port *port =  urb->context;
 808         struct oti6858_private *priv = usb_get_serial_port_data(port);
 809         int transient = 0, can_recv = 0, resubmit = 1;
 810         int status = urb->status;
 811
 812         dbg("%s(port = %d, status = %d)",
 813                                 __func__, port->number, status);
 814
 815         switch (status) {
 816         case 0:
 817                 /* success */
 818                 break;
 819         case -ECONNRESET:
 820         case -ENOENT:
 821         case -ESHUTDOWN:
 822                 /* this urb is terminated, clean up */
 823                 dbg("%s(): urb shutting down with status: %d",
 824                                         __func__, status);
 825                 return;
 826         default:
 827                 dbg("%s(): nonzero urb status received: %d",
 828                                         __func__, status);
 829                 break;
 830         }
 831
 832         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 833                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 834                 unsigned long flags;
 835
 836                 spin_lock_irqsave(&priv->lock, flags);
 837
 838                 if (!priv->transient) {
 839                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 840                                 if (xs->rx_bytes_avail == 0) {
 841                                         priv->transient = 4;
 842                                         priv->setup_done = 0;
 843                                         resubmit = 0;
 844                                         dbg("%s(): scheduling setup_line()",
 845                                             __func__);
 846                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 847                                 }
 848                         }
 849                 } else {
 850                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 851                                 priv->transient = 0;
 852                         } else if (!priv->setup_done) {
 853                                 resubmit = 0;
 854                         } else if (--priv->transient == 0) {
 855                                 if (xs->rx_bytes_avail == 0) {
 856                                         priv->transient = 4;
 857                                         priv->setup_done = 0;
 858                                         resubmit = 0;
 859                                         dbg("%s(): scheduling setup_line()",
 860                                             __func__);
 861                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 862                                 }
 863                         }
 864                 }
 865
 866                 if (!priv->transient) {
 867                         if (xs->pin_state != priv->status.pin_state)
 868                                 wake_up_interruptible(&priv->intr_wait);
 869                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 870                 }
 871
 872                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 873                         can_recv = xs->rx_bytes_avail;
 874                         priv->flags.read_urb_in_use = 1;
 875                 }
 876
 877                 transient = priv->transient;
 878                 spin_unlock_irqrestore(&priv->lock, flags);
 879         }
 880
 881         if (can_recv) {
 882                 int result;
 883
 884                 port->read_urb->dev = port->serial->dev;
 885                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 886                 if (result != 0) {
 887                         priv->flags.read_urb_in_use = 0;
 888                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 889                                         " error %d\n", __func__, result);
 890                 } else {
 891                         resubmit = 0;
 892                 }
 893         } else if (!transient) {
 894                 unsigned long flags;
 895
 896                 spin_lock_irqsave(&priv->lock, flags);
 897                 if (priv->flags.write_urb_in_use == 0
 898                                 && oti6858_buf_data_avail(priv->buf) != 0) {
 899                         schedule_delayed_work(&priv->delayed_write_work, 0);
 900                         resubmit = 0;
 901                 }
 902                 spin_unlock_irqrestore(&priv->lock, flags);
 903         }
 904
 905         if (resubmit) {
 906                 int result;
 907
 908 /*              dbg("%s(): submitting interrupt urb", __func__); */
 909                 urb->dev = port->serial->dev;
 910                 result = usb_submit_urb(urb, GFP_ATOMIC);
 911                 if (result != 0) {
 912                         dev_err(&urb->dev->dev,
 913                                         "%s(): usb_submit_urb() failed with"
 914                                         " error %d\n", __func__, result);
 915                 }
 916         }
 917 }
 918
 919 static void oti6858_read_bulk_callback(struct urb *urb)
 920 {
 921         struct usb_serial_port *port =  urb->context;
 922         struct oti6858_private *priv = usb_get_serial_port_data(port);
 923         struct tty_struct *tty;
 924         unsigned char *data = urb->transfer_buffer;
 925         unsigned long flags;
 926         int status = urb->status;
 927         int result;
 928
 929         dbg("%s(port = %d, status = %d)",
 930                                 __func__, port->number, status);
 931
 932         spin_lock_irqsave(&priv->lock, flags);
 933         priv->flags.read_urb_in_use = 0;
 934         spin_unlock_irqrestore(&priv->lock, flags);
 935
 936         if (status != 0) {
 937                 if (!port->port.count) {
 938                         dbg("%s(): port is closed, exiting", __func__);
 939                         return;
 940                 }
 941                 /*
 942                 if (status == -EPROTO) {
 943                         * PL2303 mysteriously fails with -EPROTO reschedule
 944                            the read *
 945                         dbg("%s - caught -EPROTO, resubmitting the urb",
 946                                                                 __func__);
 947                         result = usb_submit_urb(urb, GFP_ATOMIC);
 948                         if (result)
 949                                 dev_err(&urb->dev->dev, "%s - failed resubmitting read urb, error %d\n", __func__, result);
 950                         return;
 951                 }
 952                 */
 953                 dbg("%s(): unable to handle the error, exiting", __func__);
 954                 return;
 955         }
 956
 957         tty = tty_port_tty_get(&port->port);
 958         if (tty != NULL && urb->actual_length > 0) {
 959                 tty_insert_flip_string(tty, data, urb->actual_length);
 960                 tty_flip_buffer_push(tty);
 961         }
 962         tty_kref_put(tty);
 963
 964         /* schedule the interrupt urb if we are still open */
 965         if (port->port.count != 0) {
 966                 port->interrupt_in_urb->dev = port->serial->dev;
 967                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 968                 if (result != 0) {
 969                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 970                                         " error %d\n", __func__, result);
 971                 }
 972         }
 973 }
 974
 975 static void oti6858_write_bulk_callback(struct urb *urb)
 976 {
 977         struct usb_serial_port *port =  urb->context;
 978         struct oti6858_private *priv = usb_get_serial_port_data(port);
 979         int status = urb->status;
 980         int result;
 981
 982         dbg("%s(port = %d, status = %d)",
 983                                 __func__, port->number, status);
 984
 985         switch (status) {
 986         case 0:
 987                 /* success */
 988                 break;
 989         case -ECONNRESET:
 990         case -ENOENT:
 991         case -ESHUTDOWN:
 992                 /* this urb is terminated, clean up */
 993                 dbg("%s(): urb shutting down with status: %d",
 994                                         __func__, status);
 995                 priv->flags.write_urb_in_use = 0;
 996                 return;
 997         default:
 998                 /* error in the urb, so we have to resubmit it */
 999                 dbg("%s(): nonzero write bulk status received: %d",
1000                                         __func__, status);
1001                 dbg("%s(): overflow in write", __func__);
1002
1003                 port->write_urb->transfer_buffer_length = 1;
1004                 port->write_urb->dev = port->serial->dev;
1005                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1006                 if (result) {
1007                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
1008                                         " error %d\n", __func__, result);
1009                 } else {
1010                         return;
1011                 }
1012         }
1013
1014         priv->flags.write_urb_in_use = 0;
1015
1016         /* schedule the interrupt urb if we are still open */
1017         port->interrupt_in_urb->dev = port->serial->dev;
1018         dbg("%s(): submitting interrupt urb", __func__);
1019         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1020         if (result != 0) {
1021                 dev_err(&port->dev, "%s(): failed submitting int urb,"
1022                                         " error %d\n", __func__, result);
1023         }
1024 }
1025
1026
1027 /*
1028  * oti6858_buf_alloc
1029  *
1030  * Allocate a circular buffer and all associated memory.
1031  */
1032 static struct oti6858_buf *oti6858_buf_alloc(unsigned int size)
1033 {
1034         struct oti6858_buf *pb;
1035
1036         if (size == 0)
1037                 return NULL;
1038
1039         pb = kmalloc(sizeof(struct oti6858_buf), GFP_KERNEL);
1040         if (pb == NULL)
1041                 return NULL;
1042
1043         pb->buf_buf = kmalloc(size, GFP_KERNEL);
1044         if (pb->buf_buf == NULL) {
1045                 kfree(pb);
1046                 return NULL;
1047         }
1048
1049         pb->buf_size = size;
1050         pb->buf_get = pb->buf_put = pb->buf_buf;
1051
1052         return pb;
1053 }
1054
1055 /*
1056  * oti6858_buf_free
1057  *
1058  * Free the buffer and all associated memory.
1059  */
1060 static void oti6858_buf_free(struct oti6858_buf *pb)
1061 {
1062         if (pb) {
1063                 kfree(pb->buf_buf);
1064                 kfree(pb);
1065         }
1066 }
1067
1068 /*
1069  * oti6858_buf_clear
1070  *
1071  * Clear out all data in the circular buffer.
1072  */
1073 static void oti6858_buf_clear(struct oti6858_buf *pb)
1074 {
1075         if (pb != NULL) {
1076                 /* equivalent to a get of all data available */
1077                 pb->buf_get = pb->buf_put;
1078         }
1079 }
1080
1081 /*
1082  * oti6858_buf_data_avail
1083  *
1084  * Return the number of bytes of data available in the circular
1085  * buffer.
1086  */
1087 static unsigned int oti6858_buf_data_avail(struct oti6858_buf *pb)
1088 {
1089         if (pb == NULL)
1090                 return 0;
1091         return (pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size;
1092 }
1093
1094 /*
1095  * oti6858_buf_space_avail
1096  *
1097  * Return the number of bytes of space available in the circular
1098  * buffer.
1099  */
1100 static unsigned int oti6858_buf_space_avail(struct oti6858_buf *pb)
1101 {
1102         if (pb == NULL)
1103                 return 0;
1104         return (pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size;
1105 }
1106
1107 /*
1108  * oti6858_buf_put
1109  *
1110  * Copy data data from a user buffer and put it into the circular buffer.
1111  * Restrict to the amount of space available.
1112  *
1113  * Return the number of bytes copied.
1114  */
1115 static unsigned int oti6858_buf_put(struct oti6858_buf *pb, const char *buf,
1116                                         unsigned int count)
1117 {
1118         unsigned int len;
1119
1120         if (pb == NULL)
1121                 return 0;
1122
1123         len  = oti6858_buf_space_avail(pb);
1124         if (count > len)
1125                 count = len;
1126
1127         if (count == 0)
1128                 return 0;
1129
1130         len = pb->buf_buf + pb->buf_size - pb->buf_put;
1131         if (count > len) {
1132                 memcpy(pb->buf_put, buf, len);
1133                 memcpy(pb->buf_buf, buf+len, count - len);
1134                 pb->buf_put = pb->buf_buf + count - len;
1135         } else {
1136                 memcpy(pb->buf_put, buf, count);
1137                 if (count < len)
1138                         pb->buf_put += count;
1139                 else /* count == len */
1140                         pb->buf_put = pb->buf_buf;
1141         }
1142
1143         return count;
1144 }
1145
1146 /*
1147  * oti6858_buf_get
1148  *
1149  * Get data from the circular buffer and copy to the given buffer.
1150  * Restrict to the amount of data available.
1151  *
1152  * Return the number of bytes copied.
1153  */
1154 static unsigned int oti6858_buf_get(struct oti6858_buf *pb, char *buf,
1155                                         unsigned int count)
1156 {
1157         unsigned int len;
1158
1159         if (pb == NULL)
1160                 return 0;
1161
1162         len = oti6858_buf_data_avail(pb);
1163         if (count > len)
1164                 count = len;
1165
1166         if (count == 0)
1167                 return 0;
1168
1169         len = pb->buf_buf + pb->buf_size - pb->buf_get;
1170         if (count > len) {
1171                 memcpy(buf, pb->buf_get, len);
1172                 memcpy(buf+len, pb->buf_buf, count - len);
1173                 pb->buf_get = pb->buf_buf + count - len;
1174         } else {
1175                 memcpy(buf, pb->buf_get, count);
1176                 if (count < len)
1177                         pb->buf_get += count;
1178                 else /* count == len */
1179                         pb->buf_get = pb->buf_buf;
1180         }
1181
1182         return count;
1183 }
1184
1185 /* module description and (de)initialization */
1186
1187 static int __init oti6858_init(void)
1188 {
1189         int retval;
1190
1191         retval = usb_serial_register(&oti6858_device);
1192         if (retval == 0) {
1193                 retval = usb_register(&oti6858_driver);
1194                 if (retval)
1195                         usb_serial_deregister(&oti6858_device);
1196         }
1197         return retval;
1198 }
1199
1200 static void __exit oti6858_exit(void)
1201 {
1202         usb_deregister(&oti6858_driver);
1203         usb_serial_deregister(&oti6858_device);
1204 }
1205
1206 module_init(oti6858_init);
1207 module_exit(oti6858_exit);
1208
1209 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
1210 MODULE_AUTHOR(OTI6858_AUTHOR);
1211 MODULE_VERSION(OTI6858_VERSION);
1212 MODULE_LICENSE("GPL");
1213
1214 module_param(debug, bool, S_IRUGO | S_IWUSR);
1215 MODULE_PARM_DESC(debug, "enable debug output");
1216