SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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         unsigned char allow;
 306
 307         dbg("%s(port = %d)", __func__, port->number);
 308
 309         spin_lock_irqsave(&priv->lock, flags);
 310         if (priv->flags.write_urb_in_use) {
 311                 spin_unlock_irqrestore(&priv->lock, flags);
 312                 schedule_delayed_work(&priv->delayed_write_work,
 313                                                 msecs_to_jiffies(2));
 314                 return;
 315         }
 316         priv->flags.write_urb_in_use = 1;
 317
 318         count = oti6858_buf_data_avail(priv->buf);
 319         spin_unlock_irqrestore(&priv->lock, flags);
 320         if (count > port->bulk_out_size)
 321                 count = port->bulk_out_size;
 322
 323         if (count != 0) {
 324                 result = usb_control_msg(port->serial->dev,
 325                                 usb_rcvctrlpipe(port->serial->dev, 0),
 326                                 OTI6858_REQ_T_CHECK_TXBUFF,
 327                                 OTI6858_REQ_CHECK_TXBUFF,
 328                                 count, 0, &allow, 1, 100);
 329                 if (result != 1 || allow != 0)
 330                         count = 0;
 331         }
 332
 333         if (count == 0) {
 334                 priv->flags.write_urb_in_use = 0;
 335
 336                 dbg("%s(): submitting interrupt urb", __func__);
 337                 port->interrupt_in_urb->dev = port->serial->dev;
 338                 result = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO);
 339                 if (result != 0) {
 340                         dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 341                                 " with error %d\n", __func__, result);
 342                 }
 343                 return;
 344         }
 345
 346         spin_lock_irqsave(&priv->lock, flags);
 347         oti6858_buf_get(priv->buf, port->write_urb->transfer_buffer, count);
 348         spin_unlock_irqrestore(&priv->lock, flags);
 349
 350         port->write_urb->transfer_buffer_length = count;
 351         port->write_urb->dev = port->serial->dev;
 352         result = usb_submit_urb(port->write_urb, GFP_NOIO);
 353         if (result != 0) {
 354                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 355                                " with error %d\n", __func__, result);
 356                 priv->flags.write_urb_in_use = 0;
 357         }
 358
 359         usb_serial_port_softint(port);
 360 }
 361
 362 static int oti6858_startup(struct usb_serial *serial)
 363 {
 364         struct usb_serial_port *port = serial->port[0];
 365         struct oti6858_private *priv;
 366         int i;
 367
 368         for (i = 0; i < serial->num_ports; ++i) {
 369                 priv = kzalloc(sizeof(struct oti6858_private), GFP_KERNEL);
 370                 if (!priv)
 371                         break;
 372                 priv->buf = oti6858_buf_alloc(PL2303_BUF_SIZE);
 373                 if (priv->buf == NULL) {
 374                         kfree(priv);
 375                         break;
 376                 }
 377
 378                 spin_lock_init(&priv->lock);
 379                 init_waitqueue_head(&priv->intr_wait);
 380 /*              INIT_WORK(&priv->setup_work, setup_line, serial->port[i]); */
 381 /*              INIT_WORK(&priv->write_work, send_data, serial->port[i]); */
 382                 priv->port = port;
 383                 INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
 384                 INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
 385
 386                 usb_set_serial_port_data(serial->port[i], priv);
 387         }
 388         if (i == serial->num_ports)
 389                 return 0;
 390
 391         for (--i; i >= 0; --i) {
 392                 priv = usb_get_serial_port_data(serial->port[i]);
 393                 oti6858_buf_free(priv->buf);
 394                 kfree(priv);
 395                 usb_set_serial_port_data(serial->port[i], NULL);
 396         }
 397         return -ENOMEM;
 398 }
 399
 400 static int oti6858_write(struct tty_struct *tty, struct usb_serial_port *port,
 401                         const unsigned char *buf, int count)
 402 {
 403         struct oti6858_private *priv = usb_get_serial_port_data(port);
 404         unsigned long flags;
 405
 406         dbg("%s(port = %d, count = %d)", __func__, port->number, count);
 407
 408         if (!count)
 409                 return count;
 410
 411         spin_lock_irqsave(&priv->lock, flags);
 412         count = oti6858_buf_put(priv->buf, buf, count);
 413         spin_unlock_irqrestore(&priv->lock, flags);
 414
 415         return count;
 416 }
 417
 418 static int oti6858_write_room(struct tty_struct *tty)
 419 {
 420         struct usb_serial_port *port = tty->driver_data;
 421         struct oti6858_private *priv = usb_get_serial_port_data(port);
 422         int room = 0;
 423         unsigned long flags;
 424
 425         dbg("%s(port = %d)", __func__, port->number);
 426
 427         spin_lock_irqsave(&priv->lock, flags);
 428         room = oti6858_buf_space_avail(priv->buf);
 429         spin_unlock_irqrestore(&priv->lock, flags);
 430
 431         return room;
 432 }
 433
 434 static int oti6858_chars_in_buffer(struct tty_struct *tty)
 435 {
 436         struct usb_serial_port *port = tty->driver_data;
 437         struct oti6858_private *priv = usb_get_serial_port_data(port);
 438         int chars = 0;
 439         unsigned long flags;
 440
 441         dbg("%s(port = %d)", __func__, port->number);
 442
 443         spin_lock_irqsave(&priv->lock, flags);
 444         chars = oti6858_buf_data_avail(priv->buf);
 445         spin_unlock_irqrestore(&priv->lock, flags);
 446
 447         return chars;
 448 }
 449
 450 static void oti6858_init_termios(struct tty_struct *tty)
 451 {
 452         *(tty->termios) = tty_std_termios;
 453         tty->termios->c_cflag = B38400 | CS8 | CREAD | HUPCL | CLOCAL;
 454         tty->termios->c_ispeed = 38400;
 455         tty->termios->c_ospeed = 38400;
 456 }
 457
 458 static void oti6858_set_termios(struct tty_struct *tty,
 459                 struct usb_serial_port *port, struct ktermios *old_termios)
 460 {
 461         struct oti6858_private *priv = usb_get_serial_port_data(port);
 462         unsigned long flags;
 463         unsigned int cflag;
 464         u8 frame_fmt, control;
 465         __le16 divisor;
 466         int br;
 467
 468         dbg("%s(port = %d)", __func__, port->number);
 469
 470         if (!tty) {
 471                 dbg("%s(): no tty structures", __func__);
 472                 return;
 473         }
 474
 475         cflag = tty->termios->c_cflag;
 476
 477         spin_lock_irqsave(&priv->lock, flags);
 478         divisor = priv->pending_setup.divisor;
 479         frame_fmt = priv->pending_setup.frame_fmt;
 480         control = priv->pending_setup.control;
 481         spin_unlock_irqrestore(&priv->lock, flags);
 482
 483         frame_fmt &= ~FMT_DATA_BITS_MASK;
 484         switch (cflag & CSIZE) {
 485         case CS5:
 486                 frame_fmt |= FMT_DATA_BITS_5;
 487                 break;
 488         case CS6:
 489                 frame_fmt |= FMT_DATA_BITS_6;
 490                 break;
 491         case CS7:
 492                 frame_fmt |= FMT_DATA_BITS_7;
 493                 break;
 494         default:
 495         case CS8:
 496                 frame_fmt |= FMT_DATA_BITS_8;
 497                 break;
 498         }
 499
 500         /* manufacturer claims that this device can work with baud rates
 501          * up to 3 Mbps; I've tested it only on 115200 bps, so I can't
 502          * guarantee that any other baud rate will work (especially
 503          * the higher ones)
 504          */
 505         br = tty_get_baud_rate(tty);
 506         if (br == 0) {
 507                 divisor = 0;
 508         } else {
 509                 int real_br;
 510                 int new_divisor;
 511                 br = min(br, OTI6858_MAX_BAUD_RATE);
 512
 513                 new_divisor = (96000000 + 8 * br) / (16 * br);
 514                 real_br = 96000000 / (16 * new_divisor);
 515                 divisor = cpu_to_le16(new_divisor);
 516                 tty_encode_baud_rate(tty, real_br, real_br);
 517         }
 518
 519         frame_fmt &= ~FMT_STOP_BITS_MASK;
 520         if ((cflag & CSTOPB) != 0)
 521                 frame_fmt |= FMT_STOP_BITS_2;
 522         else
 523                 frame_fmt |= FMT_STOP_BITS_1;
 524
 525         frame_fmt &= ~FMT_PARITY_MASK;
 526         if ((cflag & PARENB) != 0) {
 527                 if ((cflag & PARODD) != 0)
 528                         frame_fmt |= FMT_PARITY_ODD;
 529                 else
 530                         frame_fmt |= FMT_PARITY_EVEN;
 531         } else {
 532                 frame_fmt |= FMT_PARITY_NONE;
 533         }
 534
 535         control &= ~CONTROL_MASK;
 536         if ((cflag & CRTSCTS) != 0)
 537                 control |= (CONTROL_DTR_HIGH | CONTROL_RTS_HIGH);
 538
 539         /* change control lines if we are switching to or from B0 */
 540         /* FIXME:
 541         spin_lock_irqsave(&priv->lock, flags);
 542         control = priv->line_control;
 543         if ((cflag & CBAUD) == B0)
 544                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 545         else
 546                 priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 547         if (control != priv->line_control) {
 548                 control = priv->line_control;
 549                 spin_unlock_irqrestore(&priv->lock, flags);
 550                 set_control_lines(serial->dev, control);
 551         } else {
 552                 spin_unlock_irqrestore(&priv->lock, flags);
 553         }
 554         */
 555
 556         spin_lock_irqsave(&priv->lock, flags);
 557         if (divisor != priv->pending_setup.divisor
 558                         || control != priv->pending_setup.control
 559                         || frame_fmt != priv->pending_setup.frame_fmt) {
 560                 priv->pending_setup.divisor = divisor;
 561                 priv->pending_setup.control = control;
 562                 priv->pending_setup.frame_fmt = frame_fmt;
 563         }
 564         spin_unlock_irqrestore(&priv->lock, flags);
 565 }
 566
 567 static int oti6858_open(struct tty_struct *tty, struct usb_serial_port *port)
 568 {
 569         struct oti6858_private *priv = usb_get_serial_port_data(port);
 570         struct ktermios tmp_termios;
 571         struct usb_serial *serial = port->serial;
 572         struct oti6858_control_pkt *buf;
 573         unsigned long flags;
 574         int result;
 575
 576         dbg("%s(port = %d)", __func__, port->number);
 577
 578         usb_clear_halt(serial->dev, port->write_urb->pipe);
 579         usb_clear_halt(serial->dev, port->read_urb->pipe);
 580
 581         if (port->port.count != 1)
 582                 return 0;
 583
 584         buf = kmalloc(OTI6858_CTRL_PKT_SIZE, GFP_KERNEL);
 585         if (buf == NULL) {
 586                 dev_err(&port->dev, "%s(): out of memory!\n", __func__);
 587                 return -ENOMEM;
 588         }
 589
 590         result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
 591                                 OTI6858_REQ_T_GET_STATUS,
 592                                 OTI6858_REQ_GET_STATUS,
 593                                 0, 0,
 594                                 buf, OTI6858_CTRL_PKT_SIZE,
 595                                 100);
 596         if (result != OTI6858_CTRL_PKT_SIZE) {
 597                 /* assume default (after power-on reset) values */
 598                 buf->divisor = cpu_to_le16(0x009c);     /* 38400 bps */
 599                 buf->frame_fmt = 0x03;  /* 8N1 */
 600                 buf->something = 0x43;
 601                 buf->control = 0x4c;    /* DTR, RTS */
 602                 buf->tx_status = 0x00;
 603                 buf->pin_state = 0x5b;  /* RTS, CTS, DSR, DTR, RI, DCD */
 604                 buf->rx_bytes_avail = 0x00;
 605         }
 606
 607         spin_lock_irqsave(&priv->lock, flags);
 608         memcpy(&priv->status, buf, OTI6858_CTRL_PKT_SIZE);
 609         priv->pending_setup.divisor = buf->divisor;
 610         priv->pending_setup.frame_fmt = buf->frame_fmt;
 611         priv->pending_setup.control = buf->control;
 612         spin_unlock_irqrestore(&priv->lock, flags);
 613         kfree(buf);
 614
 615         dbg("%s(): submitting interrupt urb", __func__);
 616         port->interrupt_in_urb->dev = serial->dev;
 617         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 618         if (result != 0) {
 619                 dev_err(&port->dev, "%s(): usb_submit_urb() failed"
 620                                " with error %d\n", __func__, result);
 621                 oti6858_close(port);
 622                 return -EPROTO;
 623         }
 624
 625         /* setup termios */
 626         if (tty)
 627                 oti6858_set_termios(tty, port, &tmp_termios);
 628         port->port.drain_delay = 256;   /* FIXME: check the FIFO length */
 629         return 0;
 630 }
 631
 632 static void oti6858_close(struct usb_serial_port *port)
 633 {
 634         struct oti6858_private *priv = usb_get_serial_port_data(port);
 635         unsigned long flags;
 636
 637         dbg("%s(port = %d)", __func__, port->number);
 638
 639         spin_lock_irqsave(&priv->lock, flags);
 640         /* clear out any remaining data in the buffer */
 641         oti6858_buf_clear(priv->buf);
 642         spin_unlock_irqrestore(&priv->lock, flags);
 643
 644         dbg("%s(): after buf_clear()", __func__);
 645
 646         /* cancel scheduled setup */
 647         cancel_delayed_work(&priv->delayed_setup_work);
 648         cancel_delayed_work(&priv->delayed_write_work);
 649         flush_scheduled_work();
 650
 651         /* shutdown our urbs */
 652         dbg("%s(): shutting down urbs", __func__);
 653         usb_kill_urb(port->write_urb);
 654         usb_kill_urb(port->read_urb);
 655         usb_kill_urb(port->interrupt_in_urb);
 656 }
 657
 658 static int oti6858_tiocmset(struct tty_struct *tty, struct file *file,
 659                                 unsigned int set, unsigned int clear)
 660 {
 661         struct usb_serial_port *port = tty->driver_data;
 662         struct oti6858_private *priv = usb_get_serial_port_data(port);
 663         unsigned long flags;
 664         u8 control;
 665
 666         dbg("%s(port = %d, set = 0x%08x, clear = 0x%08x)",
 667                                 __func__, port->number, set, clear);
 668
 669         if (!usb_get_intfdata(port->serial->interface))
 670                 return -ENODEV;
 671
 672         /* FIXME: check if this is correct (active high/low) */
 673         spin_lock_irqsave(&priv->lock, flags);
 674         control = priv->pending_setup.control;
 675         if ((set & TIOCM_RTS) != 0)
 676                 control |= CONTROL_RTS_HIGH;
 677         if ((set & TIOCM_DTR) != 0)
 678                 control |= CONTROL_DTR_HIGH;
 679         if ((clear & TIOCM_RTS) != 0)
 680                 control &= ~CONTROL_RTS_HIGH;
 681         if ((clear & TIOCM_DTR) != 0)
 682                 control &= ~CONTROL_DTR_HIGH;
 683
 684         if (control != priv->pending_setup.control)
 685                 priv->pending_setup.control = control;
 686
 687         spin_unlock_irqrestore(&priv->lock, flags);
 688         return 0;
 689 }
 690
 691 static int oti6858_tiocmget(struct tty_struct *tty, struct file *file)
 692 {
 693         struct usb_serial_port *port = tty->driver_data;
 694         struct oti6858_private *priv = usb_get_serial_port_data(port);
 695         unsigned long flags;
 696         unsigned pin_state;
 697         unsigned result = 0;
 698
 699         dbg("%s(port = %d)", __func__, port->number);
 700
 701         if (!usb_get_intfdata(port->serial->interface))
 702                 return -ENODEV;
 703
 704         spin_lock_irqsave(&priv->lock, flags);
 705         pin_state = priv->status.pin_state & PIN_MASK;
 706         spin_unlock_irqrestore(&priv->lock, flags);
 707
 708         /* FIXME: check if this is correct (active high/low) */
 709         if ((pin_state & PIN_RTS) != 0)
 710                 result |= TIOCM_RTS;
 711         if ((pin_state & PIN_CTS) != 0)
 712                 result |= TIOCM_CTS;
 713         if ((pin_state & PIN_DSR) != 0)
 714                 result |= TIOCM_DSR;
 715         if ((pin_state & PIN_DTR) != 0)
 716                 result |= TIOCM_DTR;
 717         if ((pin_state & PIN_RI) != 0)
 718                 result |= TIOCM_RI;
 719         if ((pin_state & PIN_DCD) != 0)
 720                 result |= TIOCM_CD;
 721
 722         dbg("%s() = 0x%08x", __func__, result);
 723
 724         return result;
 725 }
 726
 727 static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
 728 {
 729         struct oti6858_private *priv = usb_get_serial_port_data(port);
 730         unsigned long flags;
 731         unsigned int prev, status;
 732         unsigned int changed;
 733
 734         spin_lock_irqsave(&priv->lock, flags);
 735         prev = priv->status.pin_state;
 736         spin_unlock_irqrestore(&priv->lock, flags);
 737
 738         while (1) {
 739                 wait_event_interruptible(priv->intr_wait,
 740                                         priv->status.pin_state != prev);
 741                 if (signal_pending(current))
 742                         return -ERESTARTSYS;
 743
 744                 spin_lock_irqsave(&priv->lock, flags);
 745                 status = priv->status.pin_state & PIN_MASK;
 746                 spin_unlock_irqrestore(&priv->lock, flags);
 747
 748                 changed = prev ^ status;
 749                 /* FIXME: check if this is correct (active high/low) */
 750                 if (((arg & TIOCM_RNG) && (changed & PIN_RI)) ||
 751                     ((arg & TIOCM_DSR) && (changed & PIN_DSR)) ||
 752                     ((arg & TIOCM_CD)  && (changed & PIN_DCD)) ||
 753                     ((arg & TIOCM_CTS) && (changed & PIN_CTS)))
 754                         return 0;
 755                 prev = status;
 756         }
 757
 758         /* NOTREACHED */
 759         return 0;
 760 }
 761
 762 static int oti6858_ioctl(struct tty_struct *tty, struct file *file,
 763                         unsigned int cmd, unsigned long arg)
 764 {
 765         struct usb_serial_port *port = tty->driver_data;
 766
 767         dbg("%s(port = %d, cmd = 0x%04x, arg = 0x%08lx)",
 768                                 __func__, port->number, cmd, arg);
 769
 770         switch (cmd) {
 771         case TIOCMIWAIT:
 772                 dbg("%s(): TIOCMIWAIT", __func__);
 773                 return wait_modem_info(port, arg);
 774         default:
 775                 dbg("%s(): 0x%04x not supported", __func__, cmd);
 776                 break;
 777         }
 778         return -ENOIOCTLCMD;
 779 }
 780
 781
 782 static void oti6858_release(struct usb_serial *serial)
 783 {
 784         struct oti6858_private *priv;
 785         int i;
 786
 787         dbg("%s()", __func__);
 788
 789         for (i = 0; i < serial->num_ports; ++i) {
 790                 priv = usb_get_serial_port_data(serial->port[i]);
 791                 if (priv) {
 792                         oti6858_buf_free(priv->buf);
 793                         kfree(priv);
 794                 }
 795         }
 796 }
 797
 798 static void oti6858_read_int_callback(struct urb *urb)
 799 {
 800         struct usb_serial_port *port =  urb->context;
 801         struct oti6858_private *priv = usb_get_serial_port_data(port);
 802         int transient = 0, can_recv = 0, resubmit = 1;
 803         int status = urb->status;
 804
 805         dbg("%s(port = %d, status = %d)",
 806                                 __func__, port->number, status);
 807
 808         switch (status) {
 809         case 0:
 810                 /* success */
 811                 break;
 812         case -ECONNRESET:
 813         case -ENOENT:
 814         case -ESHUTDOWN:
 815                 /* this urb is terminated, clean up */
 816                 dbg("%s(): urb shutting down with status: %d",
 817                                         __func__, status);
 818                 return;
 819         default:
 820                 dbg("%s(): nonzero urb status received: %d",
 821                                         __func__, status);
 822                 break;
 823         }
 824
 825         if (status == 0 && urb->actual_length == OTI6858_CTRL_PKT_SIZE) {
 826                 struct oti6858_control_pkt *xs = urb->transfer_buffer;
 827                 unsigned long flags;
 828
 829                 spin_lock_irqsave(&priv->lock, flags);
 830
 831                 if (!priv->transient) {
 832                         if (!OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 833                                 if (xs->rx_bytes_avail == 0) {
 834                                         priv->transient = 4;
 835                                         priv->setup_done = 0;
 836                                         resubmit = 0;
 837                                         dbg("%s(): scheduling setup_line()",
 838                                             __func__);
 839                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 840                                 }
 841                         }
 842                 } else {
 843                         if (OTI6858_CTRL_EQUALS_PENDING(xs, priv)) {
 844                                 priv->transient = 0;
 845                         } else if (!priv->setup_done) {
 846                                 resubmit = 0;
 847                         } else if (--priv->transient == 0) {
 848                                 if (xs->rx_bytes_avail == 0) {
 849                                         priv->transient = 4;
 850                                         priv->setup_done = 0;
 851                                         resubmit = 0;
 852                                         dbg("%s(): scheduling setup_line()",
 853                                             __func__);
 854                                         schedule_delayed_work(&priv->delayed_setup_work, 0);
 855                                 }
 856                         }
 857                 }
 858
 859                 if (!priv->transient) {
 860                         if (xs->pin_state != priv->status.pin_state)
 861                                 wake_up_interruptible(&priv->intr_wait);
 862                         memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
 863                 }
 864
 865                 if (!priv->transient && xs->rx_bytes_avail != 0) {
 866                         can_recv = xs->rx_bytes_avail;
 867                         priv->flags.read_urb_in_use = 1;
 868                 }
 869
 870                 transient = priv->transient;
 871                 spin_unlock_irqrestore(&priv->lock, flags);
 872         }
 873
 874         if (can_recv) {
 875                 int result;
 876
 877                 port->read_urb->dev = port->serial->dev;
 878                 result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
 879                 if (result != 0) {
 880                         priv->flags.read_urb_in_use = 0;
 881                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 882                                         " error %d\n", __func__, result);
 883                 } else {
 884                         resubmit = 0;
 885                 }
 886         } else if (!transient) {
 887                 unsigned long flags;
 888
 889                 spin_lock_irqsave(&priv->lock, flags);
 890                 if (priv->flags.write_urb_in_use == 0
 891                                 && oti6858_buf_data_avail(priv->buf) != 0) {
 892                         schedule_delayed_work(&priv->delayed_write_work, 0);
 893                         resubmit = 0;
 894                 }
 895                 spin_unlock_irqrestore(&priv->lock, flags);
 896         }
 897
 898         if (resubmit) {
 899                 int result;
 900
 901 /*              dbg("%s(): submitting interrupt urb", __func__); */
 902                 urb->dev = port->serial->dev;
 903                 result = usb_submit_urb(urb, GFP_ATOMIC);
 904                 if (result != 0) {
 905                         dev_err(&urb->dev->dev,
 906                                         "%s(): usb_submit_urb() failed with"
 907                                         " error %d\n", __func__, result);
 908                 }
 909         }
 910 }
 911
 912 static void oti6858_read_bulk_callback(struct urb *urb)
 913 {
 914         struct usb_serial_port *port =  urb->context;
 915         struct oti6858_private *priv = usb_get_serial_port_data(port);
 916         struct tty_struct *tty;
 917         unsigned char *data = urb->transfer_buffer;
 918         unsigned long flags;
 919         int status = urb->status;
 920         int result;
 921
 922         dbg("%s(port = %d, status = %d)",
 923                                 __func__, port->number, status);
 924
 925         spin_lock_irqsave(&priv->lock, flags);
 926         priv->flags.read_urb_in_use = 0;
 927         spin_unlock_irqrestore(&priv->lock, flags);
 928
 929         if (status != 0) {
 930                 if (!port->port.count) {
 931                         dbg("%s(): port is closed, exiting", __func__);
 932                         return;
 933                 }
 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 if we are still open */
 958         if (port->port.count != 0) {
 959                 port->interrupt_in_urb->dev = port->serial->dev;
 960                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
 961                 if (result != 0) {
 962                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
 963                                         " error %d\n", __func__, result);
 964                 }
 965         }
 966 }
 967
 968 static void oti6858_write_bulk_callback(struct urb *urb)
 969 {
 970         struct usb_serial_port *port =  urb->context;
 971         struct oti6858_private *priv = usb_get_serial_port_data(port);
 972         int status = urb->status;
 973         int result;
 974
 975         dbg("%s(port = %d, status = %d)",
 976                                 __func__, port->number, status);
 977
 978         switch (status) {
 979         case 0:
 980                 /* success */
 981                 break;
 982         case -ECONNRESET:
 983         case -ENOENT:
 984         case -ESHUTDOWN:
 985                 /* this urb is terminated, clean up */
 986                 dbg("%s(): urb shutting down with status: %d",
 987                                         __func__, status);
 988                 priv->flags.write_urb_in_use = 0;
 989                 return;
 990         default:
 991                 /* error in the urb, so we have to resubmit it */
 992                 dbg("%s(): nonzero write bulk status received: %d",
 993                                         __func__, status);
 994                 dbg("%s(): overflow in write", __func__);
 995
 996                 port->write_urb->transfer_buffer_length = 1;
 997                 port->write_urb->dev = port->serial->dev;
 998                 result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
 999                 if (result) {
1000                         dev_err(&port->dev, "%s(): usb_submit_urb() failed,"
1001                                         " error %d\n", __func__, result);
1002                 } else {
1003                         return;
1004                 }
1005         }
1006
1007         priv->flags.write_urb_in_use = 0;
1008
1009         /* schedule the interrupt urb if we are still open */
1010         port->interrupt_in_urb->dev = port->serial->dev;
1011         dbg("%s(): submitting interrupt urb", __func__);
1012         result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1013         if (result != 0) {
1014                 dev_err(&port->dev, "%s(): failed submitting int urb,"
1015                                         " error %d\n", __func__, result);
1016         }
1017 }
1018
1019
1020 /*
1021  * oti6858_buf_alloc
1022  *
1023  * Allocate a circular buffer and all associated memory.
1024  */
1025 static struct oti6858_buf *oti6858_buf_alloc(unsigned int size)
1026 {
1027         struct oti6858_buf *pb;
1028
1029         if (size == 0)
1030                 return NULL;
1031
1032         pb = kmalloc(sizeof(struct oti6858_buf), GFP_KERNEL);
1033         if (pb == NULL)
1034                 return NULL;
1035
1036         pb->buf_buf = kmalloc(size, GFP_KERNEL);
1037         if (pb->buf_buf == NULL) {
1038                 kfree(pb);
1039                 return NULL;
1040         }
1041
1042         pb->buf_size = size;
1043         pb->buf_get = pb->buf_put = pb->buf_buf;
1044
1045         return pb;
1046 }
1047
1048 /*
1049  * oti6858_buf_free
1050  *
1051  * Free the buffer and all associated memory.
1052  */
1053 static void oti6858_buf_free(struct oti6858_buf *pb)
1054 {
1055         if (pb) {
1056                 kfree(pb->buf_buf);
1057                 kfree(pb);
1058         }
1059 }
1060
1061 /*
1062  * oti6858_buf_clear
1063  *
1064  * Clear out all data in the circular buffer.
1065  */
1066 static void oti6858_buf_clear(struct oti6858_buf *pb)
1067 {
1068         if (pb != NULL) {
1069                 /* equivalent to a get of all data available */
1070                 pb->buf_get = pb->buf_put;
1071         }
1072 }
1073
1074 /*
1075  * oti6858_buf_data_avail
1076  *
1077  * Return the number of bytes of data available in the circular
1078  * buffer.
1079  */
1080 static unsigned int oti6858_buf_data_avail(struct oti6858_buf *pb)
1081 {
1082         if (pb == NULL)
1083                 return 0;
1084         return (pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size;
1085 }
1086
1087 /*
1088  * oti6858_buf_space_avail
1089  *
1090  * Return the number of bytes of space available in the circular
1091  * buffer.
1092  */
1093 static unsigned int oti6858_buf_space_avail(struct oti6858_buf *pb)
1094 {
1095         if (pb == NULL)
1096                 return 0;
1097         return (pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size;
1098 }
1099
1100 /*
1101  * oti6858_buf_put
1102  *
1103  * Copy data data from a user buffer and put it into the circular buffer.
1104  * Restrict to the amount of space available.
1105  *
1106  * Return the number of bytes copied.
1107  */
1108 static unsigned int oti6858_buf_put(struct oti6858_buf *pb, const char *buf,
1109                                         unsigned int count)
1110 {
1111         unsigned int len;
1112
1113         if (pb == NULL)
1114                 return 0;
1115
1116         len  = oti6858_buf_space_avail(pb);
1117         if (count > len)
1118                 count = len;
1119
1120         if (count == 0)
1121                 return 0;
1122
1123         len = pb->buf_buf + pb->buf_size - pb->buf_put;
1124         if (count > len) {
1125                 memcpy(pb->buf_put, buf, len);
1126                 memcpy(pb->buf_buf, buf+len, count - len);
1127                 pb->buf_put = pb->buf_buf + count - len;
1128         } else {
1129                 memcpy(pb->buf_put, buf, count);
1130                 if (count < len)
1131                         pb->buf_put += count;
1132                 else /* count == len */
1133                         pb->buf_put = pb->buf_buf;
1134         }
1135
1136         return count;
1137 }
1138
1139 /*
1140  * oti6858_buf_get
1141  *
1142  * Get data from the circular buffer and copy to the given buffer.
1143  * Restrict to the amount of data available.
1144  *
1145  * Return the number of bytes copied.
1146  */
1147 static unsigned int oti6858_buf_get(struct oti6858_buf *pb, char *buf,
1148                                         unsigned int count)
1149 {
1150         unsigned int len;
1151
1152         if (pb == NULL)
1153                 return 0;
1154
1155         len = oti6858_buf_data_avail(pb);
1156         if (count > len)
1157                 count = len;
1158
1159         if (count == 0)
1160                 return 0;
1161
1162         len = pb->buf_buf + pb->buf_size - pb->buf_get;
1163         if (count > len) {
1164                 memcpy(buf, pb->buf_get, len);
1165                 memcpy(buf+len, pb->buf_buf, count - len);
1166                 pb->buf_get = pb->buf_buf + count - len;
1167         } else {
1168                 memcpy(buf, pb->buf_get, count);
1169                 if (count < len)
1170                         pb->buf_get += count;
1171                 else /* count == len */
1172                         pb->buf_get = pb->buf_buf;
1173         }
1174
1175         return count;
1176 }
1177
1178 /* module description and (de)initialization */
1179
1180 static int __init oti6858_init(void)
1181 {
1182         int retval;
1183
1184         retval = usb_serial_register(&oti6858_device);
1185         if (retval == 0) {
1186                 retval = usb_register(&oti6858_driver);
1187                 if (retval)
1188                         usb_serial_deregister(&oti6858_device);
1189         }
1190         return retval;
1191 }
1192
1193 static void __exit oti6858_exit(void)
1194 {
1195         usb_deregister(&oti6858_driver);
1196         usb_serial_deregister(&oti6858_device);
1197 }
1198
1199 module_init(oti6858_init);
1200 module_exit(oti6858_exit);
1201
1202 MODULE_DESCRIPTION(OTI6858_DESCRIPTION);
1203 MODULE_AUTHOR(OTI6858_AUTHOR);
1204 MODULE_VERSION(OTI6858_VERSION);
1205 MODULE_LICENSE("GPL");
1206
1207 module_param(debug, bool, S_IRUGO | S_IWUSR);
1208 MODULE_PARM_DESC(debug, "enable debug output");
1209